Rajini Rao2012-08-25 10:12:12
All for a Pail of Water: This touching photograph shows tribal women in India risking their lives in a human chain to reach water from an agricultural well. Did you know that 1 in 6 people on our planet lack access to clean drinking water? New research offers an elegantly simple solution: sun, lime juice and salt . No, it's not the recipe for a margarita! :)

What is SODIS? When water in a clear plastic bottle is placed in direct sunlight for 6 hours, the heat and ultraviolet light destroys most viruses, bacteria and parasites. This technique of Solar Disinfection reduces diarrhea and cholera by 70-80%, diseases that claim 4000+ childhood deaths per day in Africa. Researchers at Johns Hopkins University recently showed that adding juice from half a lime per bottle significantly reduced bacterial load and speeded up the process to just 30 minutes, comparable to boiling or other methods of disinfection. Lime juice contains psoralens which form covalent crosslinks between DNA strands in the presence of sunlight, a reaction that prevents DNA replication in the pathogens.

Lurking in the Murk: When the water drawn from rivers and boreholes is turbid, SODIS does not work well, since the microbes hide out under suspended particles of clay and silt. A study showed that adding a quarter teaspoon of table salt to the water neutralized charges on colloidal clay so that it sedimented out easily. Seeding the water with a little clay (of the type known as bentonite) actually hastens the clarification!

#scienceeveryday FTW! Simple solutions for #Glia .

Further (Free) Reading: http://goo.gl/QRNuO
Photo Credit: G.N.Rao, The Hindu . http://www.thehindu.com/news/national/article221561.ece

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  • Rajini Rao2011-12-11 19:19:00
    Smallest rotary motor in biology, the ATP synthase. All the work done in your body is fueled by breaking a chemical bond in ATP, the “currency of energy”. Did you know that you convert your body weight (or an estimated 50 kg) of ATP per day?!

    Where does this ATP come from? It is synthesized by an incredibly sophisticated molecular machine, the ATP synthase, embedded in the inner membrane of our mitochondria. Energy from the oxidation of food results in protons being pumped across the membrane to create a proton gradient. The protons drive the rotation of a circular ring of proteins in the membrane that in turn move a central shaft. The shaft interacts sequentially with one of 3 catalytic sites within a hexamer, making ATP (little butterflies in the movie!). The ATP synthase rotates about 150 times/second

    To visualize the rotation under a microscope, a very long fluorescent rod (actin filament) was chemically attached to the central shaft. Watch real movies (not animations!) of the enzyme spinning here: http://www.k2.phys.waseda.ac.jp/F1movies/F1long.htm

    Notice the rotation is slower with longer rods. The rotor produces a torque of 40 pN nm (40 pico Newtons x nanometer), irrespective of the load. This would be the force you would need to rotate a 500 m long rod while standing at the bottom of a large swimming pool at the rate shown in the movie.

    How did this amazing rotor evolve? The hexameric structure is related to DNA helicases that rotate along the DNA double helix, using ATP to unzip the two strands apart. The H+ motor has precedence in flagella motors that use proton gradients to drive rotation of long filaments, allowing bacteria to tumble through their surroundings. At some point, a H+ driven motor came together with a helicase like hexamer to create a rotor driving the hexamer in reverse, to synthesize ATP.

    The 1997 Nobel prize in Chemistry was awarded to John Walker and Paul Boyer for solving the structure and cyclical mechanism of the ATP synthase, respectively. This amazing enzyme was also the subject of my own Ph.D. thesis, and my first love!

    For #ScienceSunday curated by +Allison Sekuler and +Robby Bowles .
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  • Rajini Rao2012-04-30 12:20:27
    SURREAL CIRCLES: In his series Alternative Perspectives, photographer Randy Scott Slavin portrays a 360 degree view of our world by seamlessly stitching together hundreds of shots. The result is surreal art, grounded in reality. He inspires us to "go out and explore the world and take a look at the monuments and reimagine them in a different way".

    Source: http://goo.gl/2Ut69
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  • Rajini Rao2012-04-08 03:36:04
    Destination: Lítla Dímun This cloud covered muffin top is in the Faroe Islands, Kingdom of Denmark. Population: humans (0), European Storm Petrels (5000 pairs) and Atlantic Puffins (10,000 pairs). There are also herds of sheep that are rounded up each fall and lowered using nets to waiting skiffs below.
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  • Rajini Rao2012-08-26 16:28:28
    Spiders on Speed: NASA scientists inexplicably investigated web spinning by stoned spiders. Turns out that the geometrical structure of a web provides a good measure of the condition of its central nervous system.

    LSD: Webs took on a minimalist structure.

    Marijuana: Spiders made a reasonable stab at spinning webs but appeared to lose concentration about half-way through.

    Amphetamine ("speed"): Webs retained their size but showed an increase in spiral spacing and radius irregularity, as well as a decrease in building efficiency. Spiders spin their webs "with great gusto, but apparently without much planning leaving large holes", according to New Scientist magazine.

    Caffeine: makes spiders incapable of spinning anything better than a few threads strung together at random.

    Chloral hydrate (an ingredient of sleeping pills): spiders "drop off before they even get started".

    In slightly more relevant work, spiders were shown to spin perfectly good webs in microgravityhttp://goo.gl/0T7lK

    Source: http://www.trinity.edu/jdunn/spiderdrugs.htm
    Pubmed: http://goo.gl/I3U1Q

    Extrapolation to Humans: Stunning "under the influence" self portraits of artist Bryan Lewis Saunders in +Feisal Kamil's post here ▶ http://goo.gl/3xYSy  Warning: Do not try this at home!

    Confession: Since I'm jet lagged and awake since midnight, I've been abusing caffeine. I won't post a picture of my web. 

    Hilarious "mocumentary": Spiders On Drugs

    #sciencesunday +ScienceSunday #spidersunday  
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  • Rajini Rao2013-02-02 22:10:05
    The Cosmos: Macro versus Micro

    ☼ The images on the left are night views of brightly lit metropolitan cities taken from the International Space Station. On the right, are fluorescent images of neurons. Like a neuron, the city seems to have a cell body, branching dendrites and a main axon like highway extending out.

    ☼ The ancient Greeks of the Neo-Platonic school of philosophy saw  the same patterns reproduced in all levels of the cosmos, from the largest scale (macrocosm or universe-level) all the way down to the smallest scale (microcosm or sub-sub-atomic or even metaphysical-level). In their philosophy, Man is in the middle.

    ☼ Did you know that the word cosmos (Greek, κόσμος) means "order" and is the conceptual opposite of "chaos"? In Mandarin Chinese, cosmos and universe are both translated as 宇宙 yǔzhòu, which means "space-time".

    “To see a World in a Grain of Sand
    And a Heaven in a Wild Flower,
    Hold Infinity in the palm of your hand
    And Eternity in an hour.”

    -William Blake

    Source: http://infinity-imagined.tumblr.com/page/6

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  • Rajini Rao2013-01-14 23:50:29
    Panspermia: Hoax or Hope?

    Fire in the Sky: On December 29, 2012 a fireball exploded in the skies above Sri Lanka, followed by a meteorite that fell near the ancient city of Polonnaruwa. A sample was sent to the Buckingham Institute of Astrobiology and Cardiff University. Researchers now report in the Journal of Cosmology of finding fossils of diatoms enmeshed within the meteorite. Because of the way the microfossils were distributed within the rock, they rule out surface contamination.

    Panspermia (from the Greek "all" and "sperm") is the idea that life exists throughout the Universe, distributed by meteoroids, asteroids and planetoids. So, is this compelling evidence of Panspermia or life in outer space?

    Red Rain: The researchers claim that the mysterious red rain that fell in the area within days of the meteorite, reported by our own +Siromi Samarasinghe (http://goo.gl/dq7Jq), was seeded from the meteorite. Reports of red rain were first made in Homer's Iliad and may simply be from airborne algal spores. Is this red rain a red herring?

    Earthly Origin? Could it be that this rock was initially blasted off from earth, by the Mesozoic-ending impact on the Yucatan Peninsula, and is now falling back to earth after a grand journey? The article does mention that similar fossils have been found that date back to the time of the dinosaurs.

    Hasty Science? The meteorite only just landed, less than 3 weeks ago! How much of a review did this paper get? The authors make the grand statement that "identification of fossilised diatoms in the Polonnaruwa meteorite is firmly established and unimpeachable" and with several self-citations, that "the idea of microbial life carried within comets and the theory of cometary panspermia is thus vindicated". Their final sentence is a WIN, in my opinion: The universe, not humans, must have the final say to declare what the world is really like. What do you think?

    Reference (with pictures!): http://www.buckingham.ac.uk/wp-content/uploads/2011/09/Polonnaruwa-meteorite.pdf

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  • Rajini Rao2012-12-27 00:33:07
    The Venial Vegetarian: Apologies to Asians

    • I’ve never been able to get past the mental block of eating meat. I like to think that I’m logical enough that should I be stranded on a desert island with nothing to eat but cadavers, the will to live would rule supreme. I once proffered this opinion to an evangelistic vegetarian convert and she never spoke to me again. This pragmatism served me well on a recent trip to South Korea where the concept of vegetarianism is not exactly clear. “It’s just soybean”, +Thomas Kang assured me, as I spread the homogenized paste on a cabbage leaf and took a bite, “with only a bit of shrimp”. Oops, sorry! He was all apologies as he guided me to fried and battered zucchini rounds. I savored the humble vegetable with relief and reached for a second one. Too bad it was battered fish.

    • What’s a vegetarian to do, but cook up decidedly unauthentic alternatives guaranteed to have no fish sauce (shakes fist at Thai restaurants ) or errant morsels of meat that find their way into the wok? I know I’ve looked down my sharpish nose at those generic “curries” while guiltily making my own transgressions into a foreign cuisine.  So I offer abject apologies to authentic Asian cooks everywhere, while serving up my favorite non-denominational “Asian” dinner…fast, flavorful and free of flesh.

    No Recipe Tofu: The tofu is delicate, not deep fried, in this dish. Perfect for soaking up the complex flavors in the spicy sauce.

    Baby Bok Choy Stir Fry: This is a recipe adapted from +David Crowley 's blog Cooking Chat. A feast for the eye, it combines the fresh crunch of stir fried vegetables with the roasted richness of cashew.

    Ginger Noodle Salad: From +Shinae Choi Robinson 's recipe, tossed with baby greens, sesame oil and juliened ginger. I didn't have sushi ginger ("gari") on hand so she suggested I make my own.

    For Recipes, vegetarian anecdotes and pictures of my trip to S. Korea:
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  • Rajini Rao2012-02-28 23:09:28
    Art or Alcohol? Scientist Michael Davidson began taking photomicrographs of alcohol in the 1990's to raise funds for his lab. He crystallized samples of beer, tequila, vodka and other liquors on a slide, then imaged them under polarized light to reveal these gorgeous colors. You can purchase them as prints for your wall from bevshots.com.

    Note: I've not been able to post science-y stuff all week as I am carousing (er, conferencing) with 5000+ biophysicists in sunny San Diego. This collection of photographs seems particularly appropriate ;)

    H/T to Huff Post Arts for featuring this story: http://www.huffingtonpost.com/2012/02/27/artsy-side-of-alcohol_n_1304880.html#s731641
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  • Rajini Rao2012-03-08 13:34:41
    First Women in STEM: A Tribute to International Women’s Day. Here is a celebration of some of the brilliant women who changed the course of history for the better. Women of G+ , do you have stories of your own to share? What personal achievement are you proud of, whether in your family, community or profession?

    Marie Curie: First woman to receive a Nobel Prize, once for Physics (1903) and then again for Chemistry (1911), she pioneered the study of radioactivity. She died of aplastic anemia brought on by lethal exposure to radiation. Despite her two Nobels, she was not elected to the French Academy of Sciences by two votes.

    Mary Kies. Hats off to the First woman granted a US patent (1809) for a process to weave straw with silk or thread in hat making. This was a time when women could not legally own property independent of their husbands. Her patent is credited with boosting American industry at a time when Napoleon imposed a blockade on export of European goods.

    Ada Lovelace: Charles Babbage called her Enchantress of Numbers, History calls her First Programmer. Daughter of Lord Byron, in 1843, her notes on the Analytical Engine are credited as the first algorithm intended to be processed by a machine.

    Elizabeth Garrett Anderson: physician and feminist, first woman qualified to practice in England (1865), created a medical school for women, first Dean of a medical school, first woman to be elected to a school board and first woman mayor and magistrate in Britain. The day she passed the licensing exam, with highest marks, the Society of Apothecaries immediately amended their rules to prevent other women from obtaining a license.

    Florence Sabin: First woman faculty at Johns Hopkins medical school (MD, 1900 from the first batch of female medical students admitted), she was also first woman to achieve Professorship there (1917), to be elected to the National Academy of Science, and head a department at Rockefeller Institute (she was passed over for Department Head at Hopkins, in favor of her own student, a male).

    Valentina Tereshkova: Russian cosmonaut who was the First woman in space, in 1963, aboard Vostok 6. She completed 48 orbits in 71 hours. Her call sign was Chaika (seagull), a nickname that she carries to this day. She turned 75 two days ago.

    Whom did I leave out of this very short and inadequate list?
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  • Rajini Rao2012-01-21 13:41:18
    Gutsy school children. School children in Lebak, Indonesia cling perilously to a damaged rope bridge across the Ciberang river to get to school. Hopefully this publicity will mean that the bridge gets repaired quickly.

    Reuters video in the link.
    Source: http://www.nydailynews.com/news/world/brave-kids-indonesia-walk-damaged-bridge-river-school-article-1.1009218
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  • Rajini Rao2012-12-15 19:41:25
    From Protein Folding to Punjabi Pea Paneer

    ✿ Making fresh Indian cheese, or paneer, used to be a bit of a production in my home. My mother would start with not-so-fresh milk (why “waste” good milk, was her reasoning), bring it to a boil and then add lemon juice. In fascination, I watched the rapid separation of flocculant white curd from transparently greenish whey. That was my first encounter with the biochemistry of protein denaturation, although I would go on to ruin perfectly good batches of enzymes during my graduate career.

    Proteins must be folded properly – into elegant ribbons, twisted helices, graceful loops and tight turns – not only to function properly but also to stay in solution (image 2). Too much heat, salt, acid or any number of adverse conditions cause proteins to unfold just enough to get their sticky inside parts to glom together. In a concerted show of protest, they leave the solution as a precipitate. Which brings us back to cheese. The curd is gathered into cheesecloth and suspended over a bowl to drain, before being packed into a brick under some heavy pots and pans. These days, one just reaches into the freezer of the local Patel Brothers for a perfectly rectangular brick of paneer.

    ✿ This quintessential Punjabi dish of peas and paneer is called Mattar Paneer. The gravy is vegan, with richness of cashew nuts in place of dairy cream. You can make this dish entirely vegan by replacing the paneer with baby potatoes boiled in their jackets (Alu Mattar..mmm!) or a cheese substitute of your choice.

    ✿ Recipe, a memorium to a lost G+ friend, and a harrowing tale of protein denaturation from my graduate student days at: http://madamescientist.wordpress.com/2012/12/10/from-protein-folding-to-punjabi-pea-paneer/

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  • Rajini Rao2012-04-28 02:08:15
    WHEN EINSTEIN MET TAGORE: An attempt to explain Truth and Beauty at the intersection of Science and Spirituality. It was July 14, 1930 when Einstein met Rabindranath Tagore- poet, polymath and first non-European to win the Nobel for Literature (for Gitanjali).

    Regardless of your philosophy, religion or lack thereof, the following conversation will blow your mind. Excerpt:

    EINSTEIN: Truth, then, or Beauty is not independent of Man?
    TAGORE: No.
    EINSTEIN: If there would be no human beings any more, the Apollo of Belvedere would no longer be beautiful.
    TAGORE: No.
    EINSTEIN: I agree with regard to this conception of Beauty, but not with regard to Truth.
    TAGORE: Why not? Truth is realized through man.

    Read more here: http://www.brainpickings.org/index.php/2012/04/27/when-einstein-met-tagore/

    The conversation goes from the tangibility of a table to Pythagorean geometry, concluding with:

    EINSTEIN: Then I am more religious than you are!
    TAGORE: My religion is in the reconciliation of the Super-personal Man, the universal human spirit, in my own individual being.

    Many Thanks to +Pravin Bhojwani for the original share!
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  • Rajini Rao2013-08-11 17:57:23
    See Me

    Are you ready to solve this week's science mystery picture and pick up the latest in research along the way? If you know the identity of this object, don't give it away , but share some interesting (or obscure!) fact about it. Don't be shy, let your imagination fly. 

    Hint: This object has the fastest response to light in the biological world.

    Why is this cool? A recent study revealed the unexpected finding that the initial response to light was mechanical: light triggered tiny (less than one micrometer) synchronized contractions in this array that then opened mechano-sensitive ion channels to change distribution of electric charge across the surface. This form of signaling is known as mechanotransduction and is faster than more conventional chemical signaling. Do you know of a human sense that uses mechanical signaling? 

    Image Detail: False colored scanning electron micrograph that is magnified 2,500 times if printed at 10 cm. 

    Inspiration for Title: THE WHO - See Me, Feel Me - Listening to You (1975)

    #ISeeTheWorldWithScience     #ScienceSunday  

    [Answer: http://goo.gl/JgMl3o ]
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  • Rajini Rao2012-02-26 13:55:17
    WHO declares India polio-free! An incredible feat for a nation once the polio epicenter with 200,000 cases in 1988. As recently as 2009, India accounted for half of all cases in the world, but infections plummeted to 42 in 2010 and none in the last 12 months. The Indian government has spent $2 billion over the last 10-15 years to eradicate this crippling disease, which strikes children under the age of 5. However, 3 other countries (Nigeria, Afghanistan and Pakistan) have reported a massive increase in new polio cases.

    More: http://timesofindia.indiatimes.com/india/WHO-takes-off-India-from-polio-list/articleshow/12038508.cms
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  • Rajini Rao2012-11-29 02:49:31

    The Science of Tea: For 4,700 years, this infusion from the tender leaves of Camellia sinensis has been delivering a cupful of healthy antioxidants and good cheer. Did you know that tea is the most widely consumed beverage, after water? To celebrate the birthday of +Siromi Samarasinghe , who has a PhD in tea chemistry, here is some chemis-tea.

    •  Caffeine : Did you know that weight for weight, dry tea has more caffeine than coffee? But because more coffee is used per cup than tea, brewed tea has significantly less caffeine (~90 mg/250 ml).

    L-Theanine: A rare amino acid (γ-glutamylethylamide), found almost exclusively in tea, it has a calming effect on the brain. Theanine suppresses the stimulation by caffeine of brain excitability, reduces blood pressure and protects against neuronal cell death.  It is a structural analog of glutamine, which is a byproduct of glutamate, the main excitatory neurotransmitter in the brain. Theanine inhibits the transport of glutamine and dampens neurotransmission.

    Catechins: Up to 30% of dry weight in tea, catechins are a type of antioxidant also found in chocolate and wine (Mmm..). Catechins are classified as flavonoids and have been shown to reduce the risk of stroke and cancer.

    There are many other antioxidants and polyphenols found in tea. Tea is best drunk in company, but if you are alone, you can still have a tea party:

    I had a little tea party
    This afternoon at three.
    'Twas very small-
    Three guest in all-
    Just I, myself and me.

    Myself ate all the sandwiches,
    While I drank up the tea;
    'Twas also I who ate the pie
    And passed the cake to me.
    -Jessica Nelson North

    Image: http://goo.gl/fRk6V

    #happybirthdaysiromi #ScienceEveryday  
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  • Rajini Rao2012-02-05 16:31:58
    The Double Helix: Top Ten Amazing Facts about DNA!

    • You have an estimated 3 billion DNA bases in your genome.

    • Your genome would occupy about 3 gigabytes of computer storage space or fill 200 1,000-page New York City telephone directories.

    • It would take a person typing 60 words per minute, eight hours a day, around 50 years to type out all the letters of your genome.

    • If unwound and tied together, the strands of DNA in one cell would stretch almost six feet but would be only 50 trillionths of an inch wide.

    • If you unwrap all the DNA you have in all your cells it would reach to the sun and back over 600 times (100 trillion times six feet divided by 92 million miles).

    • You have an estimated 20,000 to 25,000 genes, but they only make up 2-3% of your genome. We are just starting to understand the function of your remaining “junk”.

    • Over 99.9% of your DNA sequence is the same as mine!

    • You have 1-4% Neanderthal DNA; some of you may have more :)

    • The first human genome was patched together over 13 years; today, your genome can be commercially sequenced in 2-3 months.

    • Costs for sequencing the genome are falling exponentially: from USD 3 billion in 2001 to USD1,000 today and may fall by another factor of ten!

    So, what's in your genes?
    Awesome enough for you? Want more? Check out: http://www.eyeondna.com/2007/08/20/100-facts-about-dna/
    Thanks to +Dunken K Bliths for generating this wonderful gif!
    Thank you +Konstantin Makov , for finding this hypnotic image :)
    #sciencesunday curated by +Allison Sekuler and +Robby Bowles .
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  • Rajini Rao2012-07-25 00:41:28
    Would you give up sex for eternal life? This little invertebrate, a bdelloid rotifer, has lived a celibate life for ~80 million years. The males have disappeared and the females reproduce by parthenogenesis. A drawback to this convenient scheme is that our DNA is usually repaired during meiosis, when we form gametes or germ cells.

    • Scientists bombarded these little creatures with gamma rays that would typically shatter DNA into little bits. To their astonishment, the rotifers kept reproducing even at levels of radiation five times more than other animals can endure. Their secret lies in genetic redundancy: their genomes have duplicated, so that each gene is in 4 copies. When one is damaged, the others serve as template to copy off a new version (gene conversion).

    • How did this resistance to radiation damage evolve? These animals live in fresh water pools that can dry up at any time. The rotifers can go dormant for weeks to years, springing back to life with water. Dessication has the same effect on DNA as radiation so the rotifers must have evolved to survive in their ephemeral habitats. "There could be some benefit to millions of years without sex after all", says Dr. Alan Tunnacliffe, University of Cambridge :)

    Live image of Philodina roseola , details at http://www.cellimagelibrary.org/images/41670

    Refs: (1) Gladyshev, E., and M. Meselson. 2008. Extreme Resistance of Bdelloid Rotifers to Ionizing Radiation. Proc. Natl. Acad. Sci. 105 (13): 5139-5144.

    (2) Mark Welch, D.B., J.L. Mark Welch and M. Meselson. 2008. Evidence for degenerate tetraploidy in bdelloid rotifers. Proc. Natl. Acad. Sci. 105 (13): 5145-5149.
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  • Rajini Rao2013-01-06 17:18:27
    The Genetics of Autism

    Contrary to popular belief (and Jenny McCarthy), autism is the most genetic and inheritable of all neurodevelopmental disorders. Identical twins have >80% chance of shared diagnosis, versus a much lower ~10% chance in fraternal twins, a classic indication of underlying common genetic cause. 

    What is autism? Classical autism is part of a broader group of autism spectrum disorders (ASD) characterized by (i) impaired social communication and interaction, (ii) absence or delay in language and (iii) restricted, repetitive behavior. These features vary hugely, from severe intellectual disability to mild personality traits. Intellectual delays occur in 30-60%, and 30% also suffer seizures. Current rates of diagnosis are 1 in 88 children. This is partly due to a broadening of the diagnosis but could also reflect impact of changing environment on genetic susceptibility. 

    Monogenic cases of autism are known as syndromes. About 10% of children diagnosed with ASD have mutations in a single gene. The most common is Fragile X syndrome (FXS), which accounts for 5% of autism cases with as many as 50% of individuals with FXS meeting criteria for autistic disorder. Other syndromes that present with ASD are Tuberous Sclerosis, Retts, and Neurofibromatosis. Although the primary diagnosis is not ASD, the symptoms include ASD. 

    Polygenic disorders are caused by additive effects of multiple genes. Because inheritance patterns of autism are not Mendelian, it was initially thought to be polygenic, like traits of hypertension, height or skin color. Austism superficially fits this definition because of the continuous spectrum of characteristics. But, it’s a lot more complex because no single gene appears to account for more than 1% of the non-syndromic cases. 

    Heterogenic disorders occur when mutations at any of a number of different genes can give rise to the same phenotype. In autism, many of the mutations are unique, rare and arise de novo, not being found in parents or recent ancestry. Most mutations occur on only one allele (one of two copies of the gene). Many are copy number variations, affecting gene dosage, caused by insertions and deletions in the chromosome. The emerging theory is that many different mutations converge on a common function: synaptic transmission

    The synapse: Information transfer occurs at the synapse or junction between neurons. The first synapses in human cortex appear 40 days after conception. The most dramatic change takes place around birth. During the first three years of life, more synaptic contacts are formed, but only some will be stabilized. Many genes implicated in autism (image) function at the synapse, and the timing of appearance of autistic characteristics coincides with synapse maturation.

    REF: Autism and Brain Development. Walsh et al., Cell (free read) http://goo.gl/hkbsC

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  • Rajini Rao2013-01-12 19:00:45
    Gluten Be Gone: Synthetic Biology Solution for Celiac Disease

    What is Celiac Disease? Celiac disease or gluten allergy comes from eating wheat, rye or barley. Most common in people of N. European descent, the symptoms include diarrhea, weight loss and an increased risk of cancer. 

    Why is gluten allergenic? Gluten contains an unusual protein called alpha gliadin, which has many repeats of the amino acids Proline and Glutamine (PQ motifs) that are resistant to the digestive enzymes in our stomach. In some people, these PQ-rich fragments cause severe allergy and inflammation.  

    Clinical trials: A natural bacterial enzyme from Sphingomonas capsulata that can break down PQ motifs is in clinical trials as an Oral Enzyme Therapeutic. But it works poorly in the acidic compartment of our stomach, and attempts to engineer it to become acid tolerant have not worked. 

    Trial by Acid: Univ. Washington undergraduates tackled the problem from the opposite direction. They found an enzyme called Kumamolysin-AS in a heat and acid loving bacterium Alicyclobacillus sendaiensis that was already acid tolerant. They tinkered with it, using the Fold-It protein folding game, until they found variants predicted to change the enzyme’s preference from Proline Arginine (PR) to Proline Glutamine (PQ). When they made and tested ~260 engineered enzymes, they found one that had a 116-fold increase in ability to digest the gluten peptide in acidic conditions, with a switch in preference of 800-fold! The new enzyme, KumaMAX, could be used in oral therapy or engineered into common bacteria found in yogurt to make probiotics.

    So Much Win!: This work (1) could help millions of gluten allergy sufferers world wide, (2) was done by undergraduates competing in iGEM, an annual synthetic biology competition originally founded at MIT, (3) using gaming software, (4) built on basic research done on an obscure bacterial enzyme, and (5) published with student authors in a peer-reviewed journal. 

    Images: Normal catalytic triad of protease enyzmes (left) and acid tolerant substitution (right) found in bacteria growing in acid, hot springs (middle).

    Paper: Computational Design of an α‑Gliadin Peptidase; Gordon et al., (2012) JACS 134, 20513−20520

    Team UW iGEMhttp://goo.gl/vgvTX

    #ScienceSunday   #syntheticbiology   
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  • Rajini Rao2013-08-18 19:35:31
    Rattler!  Did you know that the western diamondback rattlesnake Crotalus atrox can rattle its tail continuously for hours at frequencies approaching 90 Hz (90 times per sec)? This is twice as fast as a hummingbird's wings

    Nailing the Noise: The tail-end of the rattlesnake has a series of hollow "buttons" linked together, each made of keratin (found in our nails) and modified from the snake's scales. At birth, there is only one pre-button, but each time a snake sheds its skin, another button emerges at the end. It's a myth that one can tell the age of a rattlesnake from the number of buttons, because a snake may molt variably in a year and the buttons do break off with use.  

    Sound production in animals, is energetically expensive. But the rattler is an evolutionary marvel, optimized for minimal cost and maximal efficiency (for the aficionados, only 0.015 micromoles ATP consumed per gram muscle per twitch). Surprisingly, energy use is independent of temperature and rate of rattling. There are six sets of tailshaker muscles, arranged at 45 degree angles to the axis of the tail. All six are active during rattling, with muscles on one side contracting while those on the other side relax. This out of phase contraction generates an oscillating motion seen in the gif image

    Once you've heard a live rattler, you'll never forget it, says +Gnotic Pasta, who has plenty of snake stories to share. Do you have any cool facts or anecdotes about rattlers? Also check out +Buddhini Samarasinghe scary post on Bite Reflex of a Snake here: http://goo.gl/Lz7oBN

    ▶ BBC Video (3:50 min) on high speed filming of the rattle (look behind the rattle for the forked tongue darting out!): Slow motion rattlesnake - Slo Mo #3 - Earth Unplugged

    ▶ Great basin rattlesnake Crotalus viridis lutosus filmed by our intrepid G plusser +Gnotic Pasta  :  http://vimeo.com/64675533

    ▶ REF (old, but free): Structural correlates of speed and endurance in skeletal muscle: the rattlesnake tailshaker muscle. Schaeffer et al. http://jeb.biologists.org/content/199/2/351.long

    H/T to +Amy Robinson  for sharing the gif that inspired this post (http://goo.gl/pzi4Yv). 

  • 421 plusses - 145 comments - 204 shares | Read in G+
  • Rajini Rao2012-06-16 22:11:46
    THE KING OF FRUITS: Making Green Mango Rice. It has been said that India has only two seasons: Monsoon season and Mango season. While the monsoon replenishes Indian soil, mangoes are food for the soul.  Did you know that India holds 40% share of the world mango production?

    • Having to forgo Indian mangoes was definitely a downside of emigration to the US. I don’t count Mexican mangoes: sorry Bobby Flay, I’m sure your mango salsas are nicely fibrous and vaguely sweet ;) but these mangoes are unfit for consumption unless cooked. I brightened momentarily when President GW visited India, fell in love with the most regal of mangoes, the Alphonso, and granted special import permit for this variety, only to be foiled by the competitive Indian shopper who snaps up crates of mangoes at the going rate for gold. I recall a friend attempting to smuggle import a crate of mangoes from Toronto. At being stopped at the border and asked to throw them away, she refused indignantly. Instead, the family pulled over for an impromptu mango feast with the Customs officers joining in with gusto.

    My green mango rice was inspired by a photograph shared by +Feisal Kamil taken in his mother-in-law’s garden in Terengganu. The rice tastes even better after the flavors have had time to blend: delicately tangy and slightly sweet, sharply astringent with mustard, balanced out by creamy richness of coconut, all topped with crunchy peanuts and little pops of roasted mustard seeds. Enjoy!

    Recipe: http://madamescientist.wordpress.com/2012/06/16/the-king-of-fruits-making-green-mango-rice/
    #foodporn #food
  • 108 plusses - 144 comments - 32 shares | Read in G+
  • Rajini Rao2012-06-02 03:54:31
    I know that you believe you understand what you think I said, but I'm not sure you realize that what you heard is not what I meant.
    ― Robert McCloskey (1914-2003), Author of Make Way For Ducklings

    Image via http://imgur.com/gallery/4xPWp
  • 177 plusses - 138 comments - 127 shares | Read in G+
  • Rajini Rao2012-02-08 13:58:09
    Bug Eyes are Beautiful! If the eyes are a window to our souls, then these gorgeous compound eyes will surely win you over.

    • Each tiny facet (ommatidium) has a lens leading into a crystalline cone with light sensitive cells arranged like the segments of an orange. Individual eyes are insulated from others by a lining of pigment. The final image is a mosaic of light and dark dots, like the halftone illustrations in a newspaper. More ommatidia give a finer pattern of dots and a better resolution. Even so, the resolution of insect eyes is nowhere near that of ours: images we can separate at 60 feet would have to be one foot away to be distinguished by a honey bee.

    • The big advantage to compound eyes is that they pick up movements very well because ommatidia can quickly turn on and off to give a flicker effect. Ever tried to swat a fly? Insects can see ultraviolet too.

    These images were taken by photographer +Thomas Shahan . Checkout more insect macrophotography at: http://thomasshahan.com/photos

    More on compound eyes: http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/CompoundEye.html
  • 735 plusses - 137 comments - 459 shares | Read in G+
  • Rajini Rao2013-04-14 12:56:49
    Toxoplasma: Cats, Rats and Mind Hacks

    Bizarre and Beautiful: More than a third of the world's population is infected with the parasite Toxoplasma gondii. We pick it up from uncooked meat or from changing a cat's litter box. Although apparently harmless to healthy adults, "Toxo" is dangerous to the human fetus and to immuno-compromised people. This is why pregnant women and people with vulnerable immune systems are advised to avoid cats.

    Mind Control: The parasite infects the limbic areas of the brain near the fear and sexual attraction regions. Because it carries a gene that codes for an enzyme crucial in dopamine production, it can alter levels of this neurotransmitter. Infected rats become oddly fearless of cats but not of anything else, making it likely that they end up in a cat's intestine, the only place where the parasite can reproduce! They also make more testosterone and mate more, ensuring the spread of the parasite to other rats. The ability of parasites to manipulate host behavior for their own benefit is extremely rare in mammals because our blood brain barrier is so effective in keeping most pathogens out. But not this one.

    Why Cats Rule the Internetz: If this parasite can profoundly affect rats, what about people? Studies have shown that infected men have altered behavior and personality including a tendency to disregard rules, higher suspiciousness and jealousy. Schizophrenics are more likely to be infected with Toxoplasma, and there are disturbing links to suicide as well. A 2006 study published in the journal Proceedings of the Royal Society B found that antipsychotic drugs, commonly used to treat schizophrenia, reverse the fearlessness effects of T. gondii in the brain. This is why the CDC classifies toxoplasmosis as a neglected parasitic disease

    Image: A rosette of Toxoplasma gondii cells by Markus Meissner (University of Glasgow, UK) from Nature Methods http://goo.gl/E825h

    Facts: http://www.cdc.gov/parasites/toxoplasmosis/

  • 446 plusses - 135 comments - 128 shares | Read in G+
  • Rajini Rao2014-02-04 23:00:11
    ///\oo/\\\ Tarantula!

    ▶ All arthropods (insects, spiders and crabs) have a hard exoskeleton, which they must shed at intervals, to catch up on their growth. Known as ecdysis (from the Greek ekduo to strip off), the process is carefully coordinated, risky in the wild, and fraught with difficulties.

    ▶ For several days or even weeks before the molt, a tarantula will appear moody and sluggish, refusing to eat. It spins a cradle, called molting web (seen to the left of the gif), and lays on its back. Its heart rate increases dramatically and hemolymph ("blood") is pumped into the upper body (cephalothorax) so it nearly doubles in size. The pressure cracks the carapace along the sides and front. Wave like muscle contractions in the abdomen push the old exoskeleton, lifting it off like the lid of a can. Now comes the tricky part: the spider must work its legs out of the old shell, with forward facing hairs and bristles keeping it from slipping back inside. 

    One well-placed kick, and the ordeal is over - here, have a cigar! 

    ♺▶ Fun Facts (aka everything you wanted to know about molting but were afraid to ask):

    ● Before the molt, the spider secretes a digesting fluid that loosens and eats away at the old cuticle (yum!).

    ● While spiderlings molt several times a year, mature females, who can live up to 40 years molt every other year. Unfortunately, many males do not survive their last adult molt, because their male sex organs get stuck in the exoskeleton (sorry, guys!). 

    ● The molt lasts from ~20 minutes, in babies, to several days in the adult (ladies, you sympathize, right?). 

    ● During a molt, spiders also shed their fangs, chelicerae (which they use for grasping), their throats and stomach lining, female genital organs (omg!), and the lining of their "book lungs". 

    ● A spider that has lost a leg can regenerate one during a molt.  

    Credit: This has been a fun Google+   #collaboration  with the lovely +Carmelyne Thompson  for   #ScienceEveryday . Carmelyne gif-ed the ecdysis time-lapse for this post, after we discussed another cool spider molt gif on her post (http://goo.gl/fVo5fp). If you don't have Carmelyne in your circles for more science fun, you should! 

    More reading: http://goo.gl/U6w0cV
  • 315 plusses - 133 comments - 269 shares | Read in G+
  • Rajini Rao2012-01-25 11:42:56
    Do you use the Oxford Comma? Also known as the serial or Harvard comma, it is added after before the last conjunction in a series of three or more items.

    "I thank my parents, Ayn Rand, and God" versus "I thank my parents, Ayn Rand and God". Proponents argue that not only is the latter absurd, Ayn Rand would have rejected such a collaborative arrangement with God of all people ;)

    Whatever your thoughts on this, I do hope you don't use a double space after a period?
  • 118 plusses - 128 comments - 75 shares | Read in G+
  • Rajini Rao2013-01-31 13:34:22
    Soldier Gets a Rare Double Arm Transplant

    Brendan Marrocco was on patrol in Iraq 3 years ago when an explosion claimed all four of his limbs. He was the first Army soldier to survive a quadruple amputation. Now, he is the first soldier to receive a very rare double arm transplant at the Johns Hopkins Hospital. He is 26 years old.

    Logistics: The surgeons practiced four times on cadavers before the real thing. There were 4 teams of 3 surgeons each: one for each arm from donor and recipient. The deceased donor and living recipient do not need to match in gender, but in size, skin color, tissue and blood type.

    How They Did it: First, the skin is peeled back and bones are sawed at an angle to dovetail into each other when attached  by metal plates- good carpentry, in essence. Next, the muscles and tendons are tagged with pieces of light blue sterile bandage that are sewn in place and labeled in permanent black marker, before being connected. The arteries and veins are painstakingly attached under a microscope, and finally the skin is sewn together.

    What was New: Brendan was given an infusion of bone marrow from vertebrae in the donor’s lower spine. This lowered the chance of rejection and cut back on the use of potentially dangerous drugs.

    Two Thumbs Up: Brendan's nerves will grow into his new arms at a rate of an inch a month. In the one month since his landmark surgery, he can already move one arm around. Eventually, patients are expected to be able to "tie shoes, use chopsticks and put their hair in ponytails". Brendan might consider growing his hair longer for that :)

    Video and Story ▶ http://goo.gl/XFPse

  • 207 plusses - 127 comments - 66 shares | Read in G+
  • Rajini Rao2013-01-04 13:26:08
    Shaken, Not Stirred: The Science behind Bond's Martini

    Moderate alcohol consumption reduces risks of developing cardiovascular disease, stroke, and cataracts. As Mr Bond enjoys perennial robust health, scientists investigated whether the mode of preparing martinis has an influence on their antioxidant capacity.  Reporting in the British Medical Journal, they concluded that 007 was not only astute in matters of clandestine affairs both personal and international, he also had keen scientific and medical insights.

    Anti-Aging Antioxidants: Wonder why 007 looks so young? Shaken martinis were more effective in deactivating hydrogen peroxide than the stirred variety, and both were more effective than gin or vermouth alone (0.072% of peroxide remaining for shaken martini, 0.157% for stirred vs. 58.3% for gin and 1.90% for vermouth). More data: http://goo.gl/N44xc

    Daddy Cool? When the martini is shaken, not stirred, tiny bits of ice flake into the drink, and as they melt, the drink is distinctly colder. It's also more dilute, so perhaps Bond was going easy on the alcohol to keep his head clear?

    Vespers to Esters: Water, in the form of ice, breaks down the esters to release aromatics. "Shaking will better remove very volatile organic compounds from the liquid" explains George Christou of the University of Florida, "and air oxidizes some of the other organic compounds present, affecting its taste." This is akin to letting red wine breathe before you serve it.

    Recipe: Vesper Cocktail, from James Bond in Ian Fleming's 1953 book Casino Royale.  "Shake it very well, until it's ice cold, then add a large thin slice of lemon peel. Got it?"

    - 3 oz Gordon's Gin
    - 1 oz Stoli Vodka
    - 1/2 oz Kina Lillet

    Watch: Dashing Bonds delivering the famous one liner over the years. Vodka Martini, Shaken, Not Stirred

    Reference: Shaken, not stirred: bioanalytical study of the antioxidant activities of martinis. Trevithick et al., 1999. British Medical Journal 319:1600

    Happy Birthday to our own Mr. Bond, +Gnotic Pasta ! #DashingDansVan  
  • 167 plusses - 127 comments - 48 shares | Read in G+
  • Rajini Rao2013-03-21 23:13:10
    Down Syndrome Day

    Today, 3/21, is World Down Syndrome Day. Also known as Trisomy 21, because it involves three copies of chromosome 21 instead of the usual two (see image), Down syndrome is the most complex of genetic disorders that is compatible with survival (other trisomies are more common, but are lethal). Even Down syndrome is associated with ~50% lethality of embryos. In the US, 1 in 691 babies is born with Down syndrome.

    Too much of a good thing: Anywhere from 300 to 500 genes have altered levels and function, resulting 80 or 90 possible symptoms and an instantly recognizable phenotype (physical appearance). For example, patients have a 1 in 5 chance of developing a hole in the heart, compared to an incidence of 1:10,000 in the normal population. Down syndrome is extraordinarily complex, and my friend and colleague Roger Reeves has dedicated his career to helping patients with his research.

    Cerebellar size: Dr. Reeves showed that the reduced size of the cerebellum in patients was due to defects in the sonic hedgehog signaling pathway. Using a drug that activated this pathway, he was able to restore the number of cerebellar cells to normalcy in a mouse model of Down syndrome, pointing to a therapeutic potential for the central nervous system deficits in patients.

    Tweaking circuits: In the hippocampus—that part of the brain that’s used to navigate landmarks and fix memories, Down syndrome patients show an excess of inhibitory pathways compared to excitatory ones. A drug that is already FDA-approved works wonders on mice with the equivalent of Down syndrome, restoring balance to their brain. This drug is now in clinical trials for  Down syndrome patients.

    It's not all bad: Research on Down syndrome has broad impact. For example, having three copies of a tumor suppressor gene means that patients have a 93% lower incidence of developing certain cancers. This insight could help treat cancers in the general population. Plus, as Roger likes to say, if you know anyone with Down syndrome, they tend to be pretty interesting individuals in their own right.

    For more on Roger's research: http://goo.gl/uSJWm

    #ScienceEveryday #DownSyndrome  
  • 638 plusses - 125 comments - 188 shares | Read in G+
  • Rajini Rao2014-04-11 21:45:27
    On The Shoulders of Giants

    ♀ A sepia print of an Indian woman, a Japanese woman and a woman from Syria, dated 1885. What do they have in common? Extraordinarily, each was the first licensed female medical doctor in their country of origin. They were trained at the Women's Medical College in Pennsylvania, the first of its kind in the country. This was a time before women had the right to vote. If they did attend college at all, it was at the risk of contracting "neuralgia, uterine disease, hysteria, and other derangements of the nervous system” (according to Harvard gynecologist Edward H. Clarke). 

    An all-woman medical school was first proposed in 1846, supported by the Quakers and the feminist movement. Dr. Ellwood Harvey, one of the early teaching faculty, daringly smuggled out a slave, Ann Maria Weems, dressed as a male buggy driver, from right outside the White House. With his reward money, he bought his students a  papier maché dissection mannequin. Eventually, poverty forced him to quit teaching, but he still helped out with odd jobs. What a magnificent man!  

    Fate and fortune were to buffet Ms. Joshi's life. Married at age 9 to a man 11 years older, her husband turned out to be surprisingly progressive. After she lost her first child at age 14, she vowed to render to her "poor suffering country women the true medical aid they so sadly stand in need of and which they would rather die than accept at the hands of a male physician". She was first offered a scholarship by a missionary on condition that she converted to Christianity. When she demurred, a wealthy socialite from New Jersey stepped in and financed her education. She is believed to be the first Hindu woman to set foot on American soil. I didn't arrive until 1983 ;)

    Times were tough then. The fate of these three intrepid pioneers was a sad one. Joshi died of tuberculosis in India at the age of 21, without ever practicing. Fittingly, her husband sent her ashes back to America. Islambouli was not heard of again, likely because she was never allowed to practice in her home country. Although Okami rose to the position of head of gynecology at a Tokyo hospital, she resigned two years later when the Emperor of Japan refused to meet her because she was a woman. 

    Times have changed. My own mother was married at the age of 13 to a man also 11 years her senior. My father recalls helping my mother with her geography homework in high school. She never did attend college, despite being a charismatic woman with quicksilver wit and efficiency. Little wonder then, when I was accepted into graduate school in the US, unmarried and 21 years young, my parents staunchly stood behind me against the dire predictions of friends and relatives ("She'll come back with a yellow haired American!" "Haven't you read Cosmopolitan magazine? They are all perverts there!"). Happily, I escaped perversion, earned my doctoral degree and even gained a supportive spouse of my own. In 2004, I became only the 103rd woman to be promoted to Professor in the 111-year history of the Johns Hopkins medical school, and the first in my department, the oldest Physiology department in the country. If I have seen further it is by standing on the shoulders of giants

    #STEMwomen   #ScienceEveryday  

    More reading: http://www.pri.org/stories/2013-07-15/historical-photos-circulating-depict-women-medical-pioneers
  • 521 plusses - 124 comments - 387 shares | Read in G+
  • Rajini Rao2012-12-31 18:32:01
    The Physics of Champagne

    Champagne is a multicomponent hydroalcoholic system supersaturated with dissolved CO2 gas molecules formed together with ethanol during the second fermentation process. 

    Better Bubbles: Did you know that a bottle of champagne (0.75 L) holds about 10 g/L of dissolved CO2. When uncorked, this equals 9 L of gas (6 times the volume of the bottle!) which quickly escapes the supersaturated liquid to form a new thermodynamic equilibrium with air. The quality of champagne is determined by the fineness and abundance of effervescence: the bubbles tickle mechanoreceptors and taste buds in our mouth and carry volatile aromatics to our nose. 

    Tradition vs. Science: In bars and restaurants, champagne is poured vertically to hit the bottom of the glass, providing a thick head of foam, which quickly extends up and then progressively collapses during serving. But if champagne is poured like beer, it flows along the inclined edge and progressively fills the flute. Infrared thermography (left image) and measurement of dissolved CO2 (right image), showed that the beer-like method is best, but this scientifically validated method has not been adopted because of prejudice associated with the more plebian beer.  

    Chill It: The colder the champagne, the more dissolved CO2 is retained during the pouring step, as seen in the graph. 

    Flute or Coupe?: Measurements of CO2 fluxes outgassing from glasses showed significantly higher losses in the coupe than in the flute, providing analytical proof that the flute prolongs the drink’s chill and helps it to retain its effervescence, in contrast with the wide, broad brimmed coupe.

    The Glug-Glug Effect: The first few glasses of champagne have less dissolved CO2, so be gracious and wait your turn! This turns out to be due to the onomatopoeic “glug–glug” effect caused by the liquid first flowing rather chaotically out of the bottle, through a succession of jets of liquid and admissions of air bubble, inexorably accelerating the loss of dissolved CO2 concentration through turbulences and bubble entrapment. Later, as the bottle fills with air, the champagne flows out more smoothly retaining more CO2. 

    References: On the losses of dissolved CO(2) during champagne serving.
    Liger-Belair et al., 2010 J Agric Food Chem. 58:8768-75. 

    Monitoring gaseous CO2 and ethanol above champagne glasses: flute versus coupe, and the role of temperature. Liger-Belair et al.,2012 PLoS One. 7:e30628. 

    NPR listen/readhttp://goo.gl/O68Qe

    #HappyNewYear   #ScienceEveryday  
  • 184 plusses - 122 comments - 71 shares | Read in G+
  • Rajini Rao2013-02-23 18:24:34
    Chameleon Catapult

    Chameleons are among the slowest moving reptiles. But their protruding eyes swivel independently for a 360 degree range, so they can look for prey in different directions at the same time. When a hapless insect victim is detected, both eyes focus on it to judge range and distance with superb accuracy. 

    Ballistic Brilliance! The chameleon then launches its tongue, which is 1.5 times its body length, at speeds of 26 body lengths per second. That works out to 13.4 miles per hour or 6 meters per second . The initial acceleration is enormous: 500 m s−2 or 51g. For comparison, the space shuttle launches at 3g and humans pass out at accelerations approaching 10g. It takes less than a tenth of a second for the chameleon to snag its prey!

    Corkscrew Collagen: This impressive performance exceeds the capability of any muscle in biology by an order of magnitude. So what’s the secret behind the ballistics? The chameleon’s tongue has energy stored in concentric layers of a springy fiber, called collagen, wrapped around a stiff cartilage core. The powerful tongue muscle initially primes the spring by compressing it, to the same effect as a bow being pulled taut. When the tongue is launched, the spring uncoils explosively, slipping off the cartilage core. Once the sticky end snares the prey, the muscles work more slowly to reel it back in. This gives chameleons a competitive edge over lizards and other reptiles. Watch ▶ http://goo.gl/EBFty

    Breakfast at Dawn: Another advantage to this strategy is that the chameleon can catch its prey even at chilly temperatures when its muscles slow down drastically: unlike birds and mammals, reptiles are cold blooded and at the mercy of their ambient temperature. Watch how only the retraction of the tongue is slowed at low temperatures ▶ http://goo.gl/gT2hd

    REF ▶ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1691657/

    Slo Mo ▶ http://vimeo.com/12068409

    H/T to +Panah Rad for the gif ▶ http://i.imgur.com/XCytc.gif

  • 297 plusses - 121 comments - 372 shares | Read in G+
  • Rajini Rao2012-09-30 19:47:57
    SSHOw: Roundup Ready GM Corn Study

    • You may have seen the competing headlines. Shock findings in new GMO study: Rats fed lifetime of GM corn grow horrifying tumors, 70% of females die early! Contrast this to a more critical response, Monsanto's GM Corn And Cancer In Rats: Real Scientists Deeply Unimpressed. Politics Not Science Perhaps ?

    Confused by the Controversy? Watch the +ScienceSunday team dig into the dirt to get to the bottom of the issue, along with guest +Alan McHughen , UC Davis Professor of Plant Sciences and author of the book, Pandora's Picnic Basket; The Potential and Hazards of Genetically Modified Foods.

  • 52 plusses - 121 comments - 26 shares | Read in G+
  • Rajini Rao2012-07-29 01:41:26
    A Double Dose of Dosas: The Southern Indian Crepe. The gum-chewing, bored looking US customs officer gave me an expert once-over as I dragged my world weary rag tag family towards the airport exit. “Any mangoes, miss?” I have a theory that men in uniform have been trained to call all women Miss, even if it is obvious that we are biologically and socially old enough to qualify as their mother.

    He turned his attention to the oddly sized package on our luggage cart, “What’s that?”

    I straightened my aching, tote bag burdened shoulders with pride. “That is a table top granite wet grain grinder”. Pausing only to note his mild interest, I launched forth saying more or less the following (possibly, more): It has two granite cones that rotate within a motorized, spinning stainless steel chamber with an attached paddle and stone base.  It is used for grinding lentils and rice to a fine, fluffy batter that is fermented to make dosas. An ordinary blender with a steel blade is marginally adequate but a grinder is best for the authentic silky feel to the crepe.

    Read on, with recipes: http://madamescientist.wordpress.com/2012/07/29/a-double-dose-of-dosas-two-southern-indian-crepes/

    Masala dosas: Recently voted the number one food from around the world to try before you die. Not to hasten you to an early grave, but you must experience the dosa.

    Cabbage Adai: Should the microbial reactions in the fermentation prove too off putting or enzymatically challenging for some, I offer you a non-fermented variation with less prep time. This is a protein and lentil rich, crunchy dosa known as Cabbage Adai.
  • 101 plusses - 121 comments - 15 shares | Read in G+
  • Rajini Rao2013-01-19 00:43:29
    Cutest Protist: Love Actually..or Splitsville?

    If you go down in the woods today, you're sure of a big surprise. No, not the Teddy Bear's picnic. Giardiasis is a common and explosive form of diarrhea caused from drinking contaminated water from mountain streams and "clean water" sources, often during camping. Also known as Beaver Fever, wild animals and pets can get the runs too.  Giardia lamblia is wonderfully weird: 

    • First described in 1681 by Antony van Leeuwenhoek who examined his own diarrhea under a microscope and wrote, "I have sometimes also seen animalcules a-moving very prettily; some of ‘em a bit bigger, others a bit less, than a blood globule... furnisht with sundry little paws, where with they made such a stir".

    • Despite the heart-shape in the left image, Giardia lacks a love life and reproduces only asexually, splitting inside the cyst into two cells (trophozoites) that are released within the intestine. 

    • There are two identical and functional nuclei, which makes the stained Giardia look like it has two eyes (right image). Other organisms that have multiple sets of chromosomes house them in the same nucleus. The "smile" comes from the median body which organizes the cell's skeleton (microtubules).

    • Considered the most primitive of eukaryotes, Giardia was believed to have no mitochondria. But now it appears to have some remnants of them, called mitoplasts. Being anaerobic, they don't respire or make ATP in their mitochondria. Other eukaryotes, even anaerobic ones, have mitochondria.

    Henry Hall & His Orchestra - The Teddy Bear's Picnic (1932)

    IMAGES: Digitally colored scanning electron micrograph of Giardia cells in late stage of cell division, courtesy of CDC/ Dr. Edwin P. Ewing, Jr. (left). Stained Giardia looks like a smiley face with two nuclei eyes (right). More cute images: http://www.tumblr.com/tagged/giardia

    #ScienceEveryday     #ScienceSunday  
  • 149 plusses - 120 comments - 35 shares | Read in G+
  • Rajini Rao2013-01-25 22:43:08
    Scarecrows and Wreaths: Genetic Secrets of Efficient Food Crops
    • Ancient plants, like rice, wheat and barley, originating in the Mesozoic and Paleozoic eras, still form 95% of the Earth’s plant biomass. They use an enzyme known as RuBisCo (the most abundant protein on the planet!) to fix atmospheric carbon dioxide on to a 5-carbon sugar (ribulose bis-phosphate) to make 2 molecules of a 3-carbon sugar that eventually becomes sucrose. This is the C3 pathway, but it's not too efficient: the enzyme RuBisCo also catalyzes a competing reaction called "photorespiration" that adds oxygen to the 5-carbon sugar making a byproduct that takes many tedious and expensive steps to convert back to the useful sugar. These plants can also lose 97% of the water absorbed by the roots through stomata or pores on the underside of the leaves. If they close their stomata, they limit the diffusion of CO2 into leaves, so they have limited growth in hot, dry areas.

    • Fortunately, in the last 6-7 million years, another group of plants (sugarcane, maize, grasses) began to flourish that bypassed this problem. They evolved from the C3 plants independently, more than 60 times- a spectacular example of convergent evolution.  In these plants, a different enzyme is used to fix CO2 to make a 4-carbon sugar in the leaf cells, that is then shuttled into special wreath-like layer around the veins, known as Kranz sheath (German for wreath).  Kranz cells release CO2 from this intermediate, insulating and concentrating it around the Rubisco enzyme so that the wasteful side reaction does not occur. This highly effective C4 pathway boosts productivity by 50%. Even though C4 plants make up only 3% of plant species, they account for 30% of all carbon fixation on land.

    • How does one coax C3 plants to follow C4 pathways and boost food production in hot, dry areas, while removing more CO2 from the atmosphere? C3 plants have all the enzymes needed, but lack the specialized anatomy of the wreaths and the tight spacing between veins. It was assumed that engineering Kranz anatomy would be exceptionally difficult. In a breakthrough study, scientists noted common features of the Kranz sheath with root and stem bundles, suggesting a common developmental pathway. Working on a hunch, they showed that a gene called Scarecrow, regulates the special anatomy in both roots and leaves.  “Recapitulating the evolution of C4 structure in C3 plants is likely to be a much more manageable goal if the underlying regulatory components are already in place in roots and stems”.

    Image: Kranz anatomy in French Millet, a C4 plant. Note the bundle sheath, packed with green chloroplasts, around the central vein, and the tight spacing of less than 4 cells between the bundles. http://goo.gl/J004P  
    Read More: http://www.news.cornell.edu/stories/Jan13/Scarecrow.html

    Paper: Scarecrow plays a role in establishing Kranz anatomy in maize leaves. Slewinsky, T.L., et al. Plant Cell Physiol. 2012 Dec;53:2030-7. doi: 10.1093/pcp/pcs147.

    #ScienceEveryday when it's not #ScienceSunday .
  • 165 plusses - 118 comments - 81 shares | Read in G+
  • Rajini Rao2013-07-28 17:03:14
    What do you see? An alien sun rising over some distant desert landscape? Arid rivers marking the surface of Mars? Leave your guesses in the comments! #ISeeTheWorldWithScience  

    Forests in Flames: Actually, this photo was commissioned by the United Nations to bring attention to deforestation from coca cultivation. Three countries account for the global cocaine production: Peru, Columbia and Bolivia. A study led by SUNY professor Liliana Dávalos showed that in a 5 year period, coca cultivation led to the destruction of 890 square kilometers of rainforest. That accounts for ~6 percent of rainforest loss, totaling 14,000 square kilometers, or an area slightly larger than Jamaica. Spraying with herbicide proved to be an ineffective deterrent: for every 30 hectares sprayed, only one was eradicated. In contrast, government protection of land seemed to prevent illegal growth of coca plants. 

    Sunburned Eyes: Dilated pupils and red eyes are a visible sign of cocaine use. Curiously, cocaine was used to treat snow blindness, an extremely painful form of sunburn of the eye caused by UV radiation bouncing off snow cover. Did you know that British explorer Ernest Shackleton packed medicinal cocaine for his expedition to the South Pole in 1907 (see here for a fascinating pix http://goo.gl/W8Jo5). [Note: Shackleton came close, but did not make it to the South Pole. Later, his wife recounted : "The only comment he made to me about not reaching the Pole was "a live donkey is better than a dead lion, isn't it?"] 

    Snow Blind Friend:The Urban Dictionary defines Snow Blindness as Cocaine addiction, as heard in this poignant song by Steppenwolf: SNOWBLIND FRIEND live John Kay & Steppenwolf 1989

    He said he wanted Heaven but prayin' was too slow
    So he bought a one way ticket on an airline made of snow

    John Kay, the charismatic frontsman of Steppenwolf, was legally blind with a congenital disorder of cone cells leaving him with complete color blindness and only black and white vision.  

    Ref: Forests and Drugs: Coca-Driven Deforestation in Tropical Biodiversity Hotspots. Dávaloset al.,  http://goo.gl/B1NVbs
    Photographer: Javier Crespo, Leo Burnett Colombia advertising agency.

  • 243 plusses - 116 comments - 57 shares | Read in G+
  • Rajini Rao2013-06-08 13:13:15
    A Vaccine for Addiction: For the 1.9 million cocaine users in the US alone, addiction is a problem for which no FDA-approved therapy exists. Now, a vaccine effective on primates is ready for human trials.

    ● Cocaine blocks the recycling of dopamine so that it accumulates in the brain, prolonging and amplifying signaling in reward centers to generate that pleasurable "high". Over time, dopamine receptors (pink buckets in image) decrease, requiring higher doses of cocaine and causing a vicious cycle of dependence. There are drugs that interfere with cocaine's action but they alter these important signaling pathways and have side effects.

    The Cocaine Vaccine  triggers an immune response to the drug, that "eats up the cocaine in the blood like a little Pac-Man before it can reach the brain,” says Dr. Ronald G. Crystal, of Weill Cornell Medical College.  The trick is to chemically link a cocaine analog to the common cold virus so that the body is tricked into making antibodies. The virus is crippled and cannot cause an infection. To feel the drug high that cocaine users seek to achieve, at least 47 percent of the dopamine transporter needs to be occupied by cocaine. The vaccine reduces this occupancy to 20% so the user fails to achieve the cocaine high.

    Story: http://rt.com/usa/cocaine-vaccine-drug-pacman-219/
    Free PubMedCentral Read: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3048190/

    Image: Left, Mechanism of Cocaine at the Synapse (http://goo.gl/ZCk4K), Right, Effect of anti-cocaine vaccine on non-human primate brain, taken from Maoz et al., Neuropsychopharmacology. 2013 May 10. doi: 10.1038/npp.2013.114. Epub ahead of print)

  • 274 plusses - 115 comments - 124 shares | Read in G+
  • Rajini Rao2013-05-25 13:30:46
    Patterns in Nature

    Can you guess what this is? If you do, tell us one interesting fact about it or share your thoughts (try not to give the game away)!

    Here's one: This creature can detect infrared (thermal) radiation through heat sensitive ion channels that trigger firing of nerve fibers with accuracy >0.001 °C.

    Source: http://500px.com/photo/1539213
  • 234 plusses - 115 comments - 93 shares | Read in G+
  • Rajini Rao2013-11-28 15:41:56
    Turkey and Tryptophan: Thanksgiving Myth Debunked

    ƵƵƶƶ Why do we feel sleepy after a big meal? You've probably blamed the Thanksgiving turkey for having too much tryptophan, an amino acid that the body converts to serotonin and melatonin, two sleep-inducing compounds. But it turns out that tryptophan has to be consumed on an empty stomach and not with gourmandish excess of cranberry sauce and pumpkin pie, to be effectively blamed for your soporific state.  Did you know that even oat bran and soybeans contain more tryptophan than turkey? Check out this infographic ▶ http://goo.gl/pQtLTp .

    ƵƵƶƶ Another popular theory is that after a big meal, our body diverts blood supply to the gut, and away from the brain, to help digestion. While this seems logical, it turns out that cerebral blood flow and oxygenation are kept stable through autoregulation mechanisms even when blood flow to the gut or muscles increase after a meal or during exercise.  Blood vessels in the brain expand or contract in response to changes in blood pressure to keep flow constant. Another myth debunked! 

    ƵƵƶƶ The most likely culprits are gut-brain hormones that regulate both feeding and sleep. Orexin is one such example: it promotes hunger and alertness, but is inhibited by gastric distention and satiety. The ability of hunger to promote alertness is thought to be an evolutionary adaptation that keeps us motivated to search for food. Interestingly, mutations in orexin were recently linked to narcolepsy, a pathological form of sleepiness. Finally, it has been argued that sleep allows for "cognitive reinforcement" of the circumstances that led to your energy acquisition, an important survival skill! So when postprandial somnolence hits you after your big Thanksgiving meal, you're actually learning an age-old survival mechanism :) 

    Ref: http://www.ncbi.nlm.nih.gov/pubmed/15488646

    Gif: Via http://www.reactiongifs.com/tag/sleepy/

    #ScienceEveryday   #HappyThanksgiving  
  • 365 plusses - 113 comments - 214 shares | Read in G+
  • Rajini Rao2012-09-15 15:41:47
    It’s Nasty: Thigmonasty (Greek thigma for touch and nastos for pressed close). Closure of the Venus flytrap (Dionaea muscipula), at 40-100 milliseconds, is one of the fastest movements in plant kingdom. Little surprise that it involves action potentials: electrical signals typical of nerve communication in animals. The trap is triggered when at least two of the tiny surface hairs are touched by an insect or spider within 20 seconds of each other. Since the movement costs energy, this coincidence of two stimuli safeguards against waste from accidental triggers.

    There’s no chemistry: Unlike chemical signals, like hormones, action potentials can fire within a millisecond and propagate rapidly over long distances. Although plants have the basic necessities for electrical signaling (ion channels, motor proteins), they have nowhere near the sophistication achieved in animals. Still, an action potential can achieve speeds of up to 40 m/s in plants and is used to respond to environment.

    Touch me: The first step is the opening of mechanically-sensitive ion channels that sense deformity of the hair. This causes the cell membranes to depolarize by reducing the distribution of charges across the cell. If this depolarization exceeds a certain threshold, additional chloride and potassium channels open to let in more ions. Movement of protons makes the cell wall acidic, allowing it to soften and let the cell elongate rapidly. Despite intensive study for ~130 years, the exact mechanism of signaling is not clear.

    Food fight: Recently, the digestive juice of the Venus flytrap was analyzed and found to closely resemble enzymes used in the fight against pathogens, rather than the digestive enzymes of animals. This suggests an evolution from defense pathways to food acquisition in carnivorous plants. Read more: http://www.asbmb.org/News.aspx?id=17935

    The Doors - Touch Me

    An early submission for #sciencesunday since I will be traveling tomorrow (Viva Barcelona!).
  • 171 plusses - 113 comments - 168 shares | Read in G+
  • Rajini Rao2013-02-10 15:23:18
    The Science of Sound
    Sounds of Laughter, Shades of Life The birds do it. The bees do it too and so do you. An amazing range of animals generate sound: pressure waves caused by displacing the medium in which they travel.
    Tiny Noisemaker You may think that's the screaming baby across the airplane aisle, but human speech is at a comfortable 60 dB. The decibel, named after Alexander Graham Bell, is logarithmic in scale: an increase of 10 dB is actually ten times as loud. Anything above 85 dB is dangerously painful and the loudest sound tolerated by the human ear is 120 dB.  The loudest animal is the sperm whale at an ear-splitting 236 dB! But the prize for the biggest bang for buck goes to the lesser water boatman: perhaps in protest of its diminutive size and name, it is the loudest animal for its body size (see graph; listen here: http://goo.gl/BHKhl). Fortunately, the surrounding water dissipates 99% of its mating call or it would sound like a freight train hurtling by.  Shakespeare may dismiss life as a tale told by an idiot, full of sound and fury, signifying nothing , but to a female water boatman, the call of her mate is irresistible. Especially since he generates the sound by rubbing his…ahem.. sexual appendage against his abdomen. The lesser water boatman's call is an example of runaway evolution since there is apparently no penalty paid for the price of loudness in his case.
    Cheers to your Ears Astonishingly, the actual displacement of molecules in the air is tiny- about  11μm or 1/7th the thickness of a piece of paper at 120 dB! Did you know that the faintest sound the human ear can detect corresponds to a displacement of air molecules by ~1.1 x 10-11 m, or 11 picometers– about 1/10 the radius of a mid-sized atom? Not only can the human ear detect vibrations with a sensitivity that spans six orders of magnitude, it can also detect sounds across nearly a 10 octave range of frequencies.
    Movie Soundtrack : Across The Universe + Helter Skelter (Across The Universe)
    Sounds of laughter, shades of life
    Are ringing through my opened ears
    Inciting and inviting me.
    Limitless undying love, which
    Shines around me like a million suns,
    It calls me on and on across the universe
    • Whacky video on how we hear: Fun Science: Sound
    • Cool Info on Sound: http://www2.cose.isu.edu/~hackmart/soundwavesIengphys.pdf

  • 185 plusses - 110 comments - 58 shares | Read in G+
  • Rajini Rao2012-11-13 01:50:43
    Trypophobia: Intense fear of holes, resulting in itching and uneasiness.

    While admiring this lovely image of lotus seed pods, I stumbled across this strange phobia, also triggered by "crumpets, pumice, cavities in teeth, the Ampullae of Lorenzini in sharks, holes in concrete, bug tunnels in wood, enlarged pores of the skin, Aero Bars, holes in walls caused by bullets, bone marrow, wasps' nest, honeycomb, bubbles in dough, ant holes, veins in meat, clusters of holes". One cannot make this stuff up. It's in Urban Dictionary :)
    Did you know that 1 in 10 people suffers from a phobia? Do you have one?

    • For more strange phobias, check out: http://georgielowery.hubpages.com/hub/Trypophobia

    • Photo: "Alien Pods" by Hawaiian Sea on Flickr http://www.flickr.com/photos/area53/5250769454/

    Lotus By Rabindranath Tagore http://allpoetry.com/poem/8516495-Lotus-by-Rabindranath_Tagore
  • 115 plusses - 108 comments - 44 shares | Read in G+
  • Rajini Rao2012-05-18 01:42:00
    Does a virus have color? Actually, no. Because viruses are smaller than the wavelength of light (400-700 nanometer), they hide within its waves and can only be seen with an electron microscope. Viruses range in size from 20-300 nm. Yet, most images of viruses are pseudocolored, either to visualize detail or for aesthetic appeal.

    • Glass artist Luke Jerram, who is color blind himself, works closely with virologists to create transparent jewel-like replicas of microbes 1,000,000 times their actual size. Virus shapes can be helical, icosahedral (12-sided), prolate (capped cylinder), enveloped or rounded.

    Check out his gallery online: http://www.lukejerram.com/glass/gallery

    #scienceeveryday #sciencesunday
  • 146 plusses - 108 comments - 167 shares | Read in G+
  • Rajini Rao2012-04-13 11:10:35
    The Road to Mussoorie: Imagine if you will, a town at the foothills of the Himalayas. Blooming trees of orange Gul Mohar, aptly named "Flame of the Forest", intermix with the softer purples of the Jacaranda tree. A rickety school bus drives us across dry river beds to town, which unexpectedly boasts an eminent collection of historic schools: the Doon School, Welhams, Convent of Jesus and Mary, and my alma mater, St. Thomas Day School. Some days, snow melting in the mountains sends unpredictable torrents of cold and clear water across the roads, forcing the bus driver to turn back- to the raucous cheers of those incarcerated inside!

    In a corner of the dusty school ground, is a little cafeteria selling toffee, gum and the delectable "bun samosa". This consisted of a soft round bun, sliced only partway through, stuffed with a pea and potato samosa and served with a messy helping of Channa Masala dribbled over the open top. How I envied those with both parental blessing and pocket money to indulge in this warm and spicy comfort food! Instead, I had my buttered sandwich (albeit cut into pretty triangles) and my mother's paranoia of school yard germs as cold consolation.

    Recipe and Blog: http://madamescientist.wordpress.com/2012/04/13/chickpeas-for-comfort-spicy-channa-masala/
  • 131 plusses - 106 comments - 25 shares | Read in G+
  • Rajini Rao2012-06-28 23:18:23
    PULP FICTION? The clementine on the left was peeled, dissected to remove the pith and separate the segments, then neatly stitched back together by a laparoscopic surgeon. The sorry mess on the right was the artistry of a medical student. The trick was to do the entire "surgery" inside a closed opaque box fitted with cameras, scissors and surgical tools. Orange you glad they get to practice first?

     • Pamela Andreatta is an educator, not a surgeon, at U Michigan. She noticed that residents and interns struggled at laparoscopic surgery, to the detriment of the patient. So she came up with a low cost training alternative. Surgeons say that the exercise is a remarkable simulation of the pelvic anatomy.

    • The fruit of their labor can now be transplanted in any country (it is being field tested in Ghana). Students who cannot concentrate will be canned.

    Source: http://www.npr.org/blogs/health/2012/06/27/155838967/what-clementines-can-teach-surgeons
  • 100 plusses - 105 comments - 26 shares | Read in G+
  • Rajini Rao2012-03-27 22:58:56
    Uncork the Muse! Is creativity sparked by altered cognitive states brought on by insanity, sleep state, mood, or substance use? Alcohol, in particular, has been credited with inspiring creative geniuses from Socrates to Beethoven, Poe, Hemingway, Coleridge, and Pollock. In contrast to analytical problem solving, which requires high attention span and working memory capacity, creative problem solving involves flashes of intuition. A recent study tested the effect of moderate alcohol consumption on creative thinking.

    The Experiment: Male social drinkers were administered alcohol to a blood alcohol level of 0.07 (just below the drinking limit for driving) then given the RAT (Remote Associates Test). For example, participants were given three target words such as PEACH, ARM, and TAR, and were tasked with finding a fourth word, such as PIT, that forms a good two-word phrase with each of the target words. This type of word association involves out of the box, creative thinking. They were also asked if they came by the association intuitively (as in an Aha! moment).

    The Results: As seen in the figure, intoxicated participants reported significantly more insightful solutions than sober participants. Even better, they solved significantly more RAT problems (M = .58, SD = .13) than their sober counterparts (M = .42,SD = .16). They also solved them faster (M = 11.54 s, SD = 3.75) compared to sober controls (M = 15.24 s, SD = 5.57). The study concluded that moderate alcohol consumption improved creative memory tasks. Cheers!

    Extra Credit: How was the alcohol administered? Why did they choose men and not women? What did the men do while they consumed their drinks?

    Source: Uncorking the muse: Alcohol intoxication facilitates creative problem solving. Andrew F. Jarosz, Gregory J.H. Colflesh ,and Jennifer Wiley. Department of Psychology, University of Illinois at Chicago
  • 68 plusses - 105 comments - 29 shares | Read in G+
  • Rajini Rao2014-02-23 15:02:03
    Dance of the Peacock Spider

    Doing the Y: Only 4 mm in size, the Australian male peacock spider (Maratus volans) puts on an impressive courtship display, rivaling the Village People in Peacock Spider Dances to YMCA . Described by researchers as multi-modal, the dance includes 3rd leg waves, synchronized unfurling of colorful belly flaps, abdominal bobbing and pedipalp flickers. As if these visual displays were not enough, the spider generates bursts of vibrations carried through the ground to signal his passion for his lady love. 

    Darwin's Dilemma: Is there an selective advantage to such complexity? How did it evolve? As the rituals get more elaborate, there may be diminishing returns given the limitations of biological cost and sensory perception. Translation: is it a waste of time? :) But studies show that redundant signals allow our spidery suitor to adapt to varied environments. Too dark to see the colorful fans? The seismic display compensates for lack of light.It is thought that each signal carries a different message for the female to evaluate. It's also an exercise in self preservation: males risk falling prey to the cannibalistic tendency of the female spider. Web building male spiders generate shudder vibrations that measurably calm the female's aggression. Others present a silk-wrapped nuptial gift that distracts the female long enough to get the deed done. An unusual tactic called thanatosis is to is to feign death when the female shows signs of terminating the romantic act. Once the female has dragged off the motionless male, she begins to feed on his nuptial gift upon which the male quickly revives to resume mating!

    So humans, do you see any parallels in strategy? Perhaps, you too met your mate on the web?

    ▶Nuptial gifts: http://goo.gl/VCsbzN
    ▶Spider Shudders: Male courtship vibrations delay predatory behaviour in female spiders. Wignall and Herberstein (2013) http://goo.gl/wT29bD
    ▶Dance Moves: Multi-Modal Courtship in the Peacock Spider, Maratus volans. Girard et al. (2011) http://goo.gl/SlIK1E
    ▶Gifs: via http://biomorphosis.tumblr.com/

  • 374 plusses - 103 comments - 303 shares | Read in G+
  • Rajini Rao2013-08-25 20:52:20
    Science Mystery Photo: Are these the pages of an ancient book? Flaming rivulets of lava? Go ahead and take a wild guess. 

    Hint: These are extraordinarily efficient assembly lines producing up to 31,000 "products" per second or 2.7 billion per day! The special arrangement seen in the photos increases the surface area of the "factories" by 20 fold, with optimum spacing for maximum efficiency. 

    Cool Fact: The products of this factory are released by a mechanism known as surface tension catapult, achieving speeds of  1.8 m per sec, although they only need to be ejected about 1 mm or so. 

    Shhh! Do you already know what this is? Don't be a spoilsport, be a fun guy (or gal!). Share an interesting fact about it in the comments. We'll all be wiser in the end. 

    Photo credits: Brian J. Kelly, Kip Taylor-Brown and Claudio Pia

    #iseetheworldwithscience   #ScienceSunday  
  • 147 plusses - 102 comments - 25 shares | Read in G+
  • Rajini Rao2013-04-03 22:25:01
    Happy (birthday) HIRL

    A big thank you to all my friends, well-wishers and fellow incorrigibles for today's extravaganza. How awesome to have not one, but a double-superhero hashtag #Wolverine2WonderWomanHappyBD accompanied by a #punderstorm and trending of my favorite #ScienceEveryday .  

    This began with a mysterious package. I came home to find it partly open.
    Husband: The calendar you ordered has arrived
    Me: I didn't order a calendar
    Son: See, I told you it was from her G+ friends!

    A few minutes later, my giggles over images of a moustachioed Freddie Mercury +Buddhini Samarasinghe trying to break free with a pipette,  Wonder Woman +Thomas Kang in drag, and variously exposed males ( Dan and Peter identities protected, you know who you are) force me to explain my (undeserved!) reputation as a connoisseur of men in kilts. Was it my imagination, or did my husband just pull his knees in a bit? ;) Oh yes, my secret admirer +Hugh Jackman (sadly, the secret part refers to his inexplicable ignorance of my existence), being devoured by cake queen +Kimberly Chapman !

    Then I had a most distinguished delivery man in the form of +William McGarvey , who came bearing gifts of strawberries, chocolates, and a superb Pinot Noir. When I saw the card, I knew there had  been a whole lot of monkeying going around. Appropriately, I served Bill my last slice of banana bread.

    Thank you all for making today, and everyday, so special!
  • 202 plusses - 101 comments - 0 shares | Read in G+
  • Rajini Rao2013-02-27 23:19:16
    Fat Cell

    Meet the adipocyte or fat cell, the first in an occasional series of #excyting cell types. Each cell, marked by the blue nucleus, is loaded with fat droplets stained in green. 

    Why we need fat: Adipocytes have three important jobs: they store energy in the form of fat, they secrete hormones and they respond to insulin to meet the immediate energy needs of our bodies. Obese people who carry out these three functions are metabolically healthy and actually have 38% lower mortality risk. If fat is stored elsewhere, it leads to metabolic disease.

    Good fat, bad fat, white fat, brown fat: Not all fat cells are equal. While white fat stores energy, brown fat burns energy to produce heat. Babies and hibernating animals use brown fat to keep warm. The brown color comes from being packed with iron-rich mitochondria. In brown fat, these powerhouses are "uncoupled": they use energy from fat to pump protons across their membrane but the protons run backwards in a wasteful exercise in futility that generates heat.

    Fat is plastic: white fat cells can convert to brown fat by a process induced by cold temperatures. This is a good thing: animals with more brown fat are more resistant to diabetes and obesity.

    Fat cells are constant: It is generally believed that the number of fat cells is nearly constant, beyond childhood. Rather, it is the size of the cell that changes. When mature, an adipocyte may be 10 or 20 times its original size.

    Image: 3T3-L1 derived adipocytes stained for lipid droplets (green) and DNA (blue). Finalist, GE Healthcare cell imaging competition, 2012 ▶ http://goo.gl/hkzBE Inset, colored scanning electron micrograph of a fat cell. Most of the adipocyte's volume is taken up by a large lipid (fat or oil) droplet. Fat accumulation starts with a few small lipid droplets which coalesce to make one large droplet. Magnification: x10,000 when printed at 10 centimetres wide.  ▶ http://goo.gl/sZ6hp

  • 169 plusses - 100 comments - 48 shares | Read in G+
  • Rajini Rao2012-07-17 23:59:42
    How to Write Good: I'm working on a research paper and I have to remind myself of these golden rules.   :)

    • Avoid Alliteration. Always.
    • Eschew obfuscation.
    • One word sentences? Eliminate.
    • Don't repeat yourself, or say again what you have said before.
    • The passive voice is to be avoided.
    • Avoid cliches like the plague. (They’re old hat.)
    • Foreign words and phrases are not apropos.
    • Poofread carefully to see if you any words out.
    • Don't overuse exclamation marks!!!
    • Take the bull by the hand and avoid mixing metaphors.
    • Be more or less specific.
    • Understatement is always best.
    • Who needs rhetorical questions?
    • And always be sure to finish what

    More: http://goo.gl/eDTuP
  • 159 plusses - 100 comments - 73 shares | Read in G+
  • Rajini Rao2012-04-23 00:26:21
    Memories of Moosewood and Enchanted Broccoli Forest Soup

    When I arrived in the US at age 21, more years ago than all the digits on your hands and feet, I was in for a culinary disappointment, if not a culture shock. Indeed, the shock was on the other foot, if weak puns are permitted.

    After an entire week of eating raw cauliflower and broccoli in salads at one memorable Gordon Conference in New Hampshire (notwithstanding the awesome science!), I finally informed the chef that the difference between a vegetarian and a goat was that only the latter did not need their food cooked.

    In the midst of this culinary calamity, my housemate Catherine (a lovely British-American transplant) gave me the Moosewood cookbook. Inspired to spread my fledgling wings in our tiny apartment kitchen, I worked through the recipes. Yesterday, I recreated this soup.

    Oh, if you were curious: Catherine’s inscription on my book (last picture) ends with the Bengali words “Ami Tumarke Bhalo bashe”. Google Translate is not needed for those universal words of affection, “I love you”. Much comfort and sustenance to all!

    Recipe and more: http://madamescientist.wordpress.com/2012/04/22/memories-of-moosewood-and-enchanted-broccoli-forest-soup/
  • 63 plusses - 99 comments - 7 shares | Read in G+
  • Rajini Rao2013-11-29 19:55:22
    Petrichor: Smell of the Earth

    A heavenly scent: Do you love the smell of soil after a fresh bout of rain? Are you a fan of the earthy smell of beets? There is a word for that: petrichor.  It comes from the Greek petros, meaning stone and ichor, the fluid that flows in the veins of the gods. It is defined as "the distinctive scent which accompanies the first rain after a long warm dry spell". 

    Geosmin: After puzzling over the smell of soil for over a hundred years, scientists have pinned the source to Streptomyces, the soil bacterium that also gifts us with the most antibiotics. The bacteria release volatile compounds when disturbed, like the bicyclic alcohol, geosmin (named for "earthy smell"). Did you know that the human nose is incredibly sensitive to geosmin? We can detect as little as ten parts per trillion! 

    One hump or two?: Bactrian camels are reputed to detect water from 50 miles away. The signature smell of Streptomyces is easily carried across the desert and picked up by the camel's sensitive nose. In return, the bacterium probably benefits from having its spores spread around. The musty earth scent of some Cactus flowers is also due to a derivative of geosmin. It lures pollinating insects by a promise of water. This is known as floral mimicry. Unfortunately, fish that absorb minute amounts of geosmin from water don't taste that great.

    ✿ This smelly chemistry post is a birthday present for our favorite Google+ chemist +Siromi Samarasinghe! Check out other odoriferous posts in Sirome's honor by +Chad Haney (http://goo.gl/INUpXi , http://goo.gl/SN4WQs and http://goo.gl/XpVL9R). 

    Image: Streptomyces coelicolor http://microbewiki.kenyon.edu/index.php/Streptomyces

    Source and Ref: http://www.bios.niu.edu/meganathan/smell_of_soil.shtml

  • 271 plusses - 98 comments - 98 shares | Read in G+
  • Rajini Rao2012-06-26 12:51:52
    SMALLEST CELL: Mycoplasma. The pink circles are a type of bacterium only 0.1 μm in diameter (0.0001 mm, or about 0.0000039 inches).

    • They have the fewest known genes of any free living organism. Mycobacterium laboratorium is synthetic bacterium patented by Craig Venter, who has whittled down the minimum number of genes to 382.

    • Lacking a cell wall, they are immune to common antibiotics like penicillin that target cell wall synthesis. M. pneumoniae and M. genitalium cause human disease.

    • In the lab, they are a common contaminant of cell culture and can seriously confound results. Difficult to detect unless one specifically looks for them, mycoplasma contamination is estimated at minimum of 10%.

    Scanning Electron Micrograph: Kevin MacKenzie, University of Aberdeen, Wellcome Images. Mycoplasma on surface of bone-forming osteoblast cells.

  • 99 plusses - 98 comments - 32 shares | Read in G+
  • Rajini Rao2013-02-14 00:42:18
    Strawberry Scones and Civili-Tea: A Pragmatist’s Valentine

    A marriage made by matchmakers Ours is a pragmatic partnership. Social, economic and educational equity? Check. Common Genetic Pool? Yes, his grandmother and mine are cousins once removed. Horoscopes matched? Expeditiously ignored, unless the meeting does not go well in which case the alignment of stars will turn out to be sadly (but conveniently) out of synchrony.

    Tea's a Crowd It begins with an elaborately casual tea staged at my future in-law’s home: Eligible Bachelor #1 meets Nubile College Grad under four pairs of fondly hopeful parental eyes. Bachelor drops his teaspoon and is struck dumb. Bachelorette studiously ignores the handsome klutz and strikes up an animated discussion with groom-to-be’s father. Not an auspicious beginning. Considering that the chick will soon fly the coop (my tickets to America purchased, scholarship to graduate school in hand), the situation warrants bringing in the heavy weights, no less than a sari-clad replica of the Dowager of Downton Abbey! Post haste, the grandparents arrange a second meeting in neutral territory and after some masterful maneuvering I find myself tête à tête amidst the bougainvilleas and overgrown crotons of my grandmother’s garden. Two years later, we are married and have so remained for more than two and a half decades although I tossed off my sacred mangalsutra immediately and my husband has never worn a wedding ring.

    I'll Pass on the Roses, Thanks! It should therefore come as little surprise to you, dear reader, that Valentine’s Day passes by unnoticed in Madamescientist’s household. But that one and half hour ride from Baltimore to Philly on a snowy Sunday morning, so I can chair a meeting before flying on to another in Houston..that was much appreciated, thank you! So when +Michelle Beissel shared a recipe for heart shaped strawberry scones, I thought it would be nice if we raised a cup of cheer in memory of that fateful tea party so many years ago.

    Pictures and Recipe: http://madamescientist.wordpress.com/2013/02/13/strawberry-scones-and-civili-tea-a-pragmatists-valentine/

    Michelle's Potager Garden: http://soupedupgarden.blogspot.com/

    #Incorrigibilitea #IncorrigibleValentine #ValentinesDay  
  • 157 plusses - 97 comments - 10 shares | Read in G+
  • Rajini Rao2012-11-09 13:07:02

    For +Shinae Choi Robinson 's Indian Cookalong Event see here: http://goo.gl/Bo5uh

    Reshared text:
    Channa Masala

    1. Chickpeas: If you are using dry chickpeas (garbanzo beans), soak overnight and cook with plenty of water until softened. I like to add some flavoring during cooking (a bay leaf, a dash of oil, salt to taste, a clove of garlic,3-4 whole peppercorns and cloves). If using canned, drain and set aside.

    2. Potatoes: Boil 3-4 potatoes in their skin. Peel (or leave the skin on), cut into big cubes, and set aside.

    3. Spice Blend: Using a spice mill, clean coffee grinder or mortar and pestle, coarsely grind 1 tsp cumin seeds, 1 tsp fennel seeds, 1 tbsp coriander seeds, 3-4 peppercorns, 2 cloves. You can use more or less of each, just keep the proportions similar.

    Substitute with powdered spices (milder flavor): 1 tsp garam masala, 1 tbsp coriander powder and 1 tsp cumin powder.

    4.Finely mince: 2 small onions, 2 green chillies (optional), 1 inch piece of fresh ginger root, 2 cloves of garlic. I like to use a food processor to chop them all together.

    5. Caramelize onions: To make the gravy, begin by heating a couple tbsp vegetable oil in a heavy bottomed pan. Add the minced onion mixture and cook on high for a few minutes, stirring, while the onions lose water. Reduce heat to low and continue cooking for about 10 minutes or until the onions turn light brown and pull away from the sides of the pan. Stir occasionally, don't let it burn.

    6. Tomatoes: Chop 2-3 tomatoes, add to the onion mixture and continue cooking.

    7. Spices: Add the freshly ground or powdered spices. Add a tsp of turmeric powder and a quarter tsp of chilli powder/cayenne pepper (optional). Also add salt to taste and a good pinch of sugar to balance flavor. Mix in the spices while on low heat.

    8. Potatoes: Add the cubed potatoes, and mix them in.

    9. Chickpeas: Add the cooked chickpeas in their water. If using canned, add drained chickpeas and then add a cup or more of water to make a gravy of your choice of thickness (it will continue to thicken).

    10. Garnish: After the chickpeas have simmered in their tomato-spice broth, squeeze in half a lemon (or lime) and garnish with chopped cilantro/coriander leaves. If it seems too spicy, you can add a dash of cream or a dollop of yogurt just before taking it off the heat.

    Serve hot, with the _pulao rice, cucumber raita and optional store bought naan (Indian bread).

    Blog post: http://madamescientist.wordpress.com/2012/04/13/chickpeas-for-comfort-spicy-channa-masala/
  • 126 plusses - 97 comments - 21 shares | Read in G+
  • Rajini Rao2012-07-12 13:29:29
    Eeek!: The Smithsonian Store offers this acrylic, Glow-in-the-Dark computer mouse with a real spider for $28. Arachnophobic? Try their beetle version (http://goo.gl/sludF) for half the price.
    Pros: USB compatible, creeps out co-workers, purple
    Cons: Not wireless, creeps out co-workers, purple
    H/T HuffPo
  • 105 plusses - 97 comments - 45 shares | Read in G+
  • Rajini Rao2013-12-29 23:38:50
    The Biology of Transparency

    The Invisible Man: Have you ever wished to be invisible? Transparency is quite common in biology, being particularly useful as camouflage in the open ocean where there is nothing to hide behind. There is an astonishing variety of transparent jellyfish, glass squid, worms and this creepy-crawly crustacean from the "twilight zone" of the deep sea seen in the image. 

    How does it work? To be transparent, light must pass through without being absorbed or scattered. Most organic molecules do not absorb light in the visible range, except for the visual pigments of the eyes, which must absorb light to function. Light scattering is caused by changes in refractive index which determines how light is bent as it passes through (see http://goo.gl/7l6zFC). To be perfectly transparent, the refractive index should be the same throughout. This is clearly a challenge in biological tissues, where lipid membranes and protein/DNA rich organelles (like mitochondria or nuclei) are much denser than the surrounding cytoplasm. So transparent animals resort to a number of tricks to avoid light scattering.

    See Right Through Me: One way is to become extremely flat! Since there is an exponential relationship between thickness and light absorption/scattering, a 1 cm thick tissue that is 60% transparent will achieve 95% transparency if it is only 1 mm thick. Some tissues, like the lens of our eyes, undergo drastic reduction of complexity, relying on neighboring cells to feed them. At the ultrastructural level, surfaces can be cloaked in submicroscopic bumps, smaller than half the wavelength of light that average out the differences in refractive indexes. Known as moth eye surfaces, these are responsible for the transparency of the beautiful glasswing butterfly Greta oto (see http://goo.gl/KS85mo).

    I See You!: It's hard to keep the gut transparent, unless one only eats transparent food, like the larvae of the phantom midge that sucks out clear fluids from its prey. Also, transparency can be foiled by predators that have evolved to use UV light or even polarized light to spot their prey, since underwater light is polarized particularly in the horizontal plane. A study with squid showed that they attacked plastic beads with birefringence, preferentially over beads without this optical property. Something to think about before you invest in an invisibility cloak!

    GIF: This 9 cm long amphipod is nearly completely transparent. Via http://goo.gl/bL14Oy from the video below.

    Video: For a short 2:41 minute video of more stunning transparent creatures, watch Deep Sea Creatures - Nature's Microworlds - Episode 11 Preview - BBC Four


    Musical InspirationQueen - 'The Invisible Man'

    #ScienceSunday   #ScienceEveryday  
  • 568 plusses - 96 comments - 341 shares | Read in G+
  • Rajini Rao2013-09-15 13:09:14
    Do You Like Green Eggs And Ham?

    Yes, I like them, Sam-I-Am
    White eggs, Brown eggs,  Pink ones too
    But Tell me, how Do they turn Blue?
    (With apologies to Dr. Seuss) 

    Egg color in birds evolved for obvious reasons of camouflage and recognition, and for less obvious reasons such as thermal regulation, protection against UV light, and even antimicrobial defense. Chicken eggs are commonly white (no pigment), or brown (protoporphyrin). Rare breeds from China and Chile lay blue eggs, colored by the bile pigment biliverdin, a breakdown product of the hemoglobin in red blood cells.  Biliverdin is normally excreted by liver cells into the bile. So how does it end up in the egg shell? 

    Organic anion transporters are proteins that move a large number of compounds- drugs, toxins, hormones and bile pigments, across cell membranes, as part of the liver's detoxifying day job. Genetic sleuthing mapped the blue color trait to a region of a chicken chromosome. Here was a gene for a transporter protein, SLCO1B3, that could provide blue-green biliverdin to color the shell. But why was the gene inexplicably turned on only in the shell gland of the blue egg laying chicken?

    Endogenous retroviruses (ERV) are ancient viruses that inserted randomly into the genomes of prehistoric birds. One such viral fragment inserted right next to the SLCO1B3 gene in blue egg laying chickens, where it behaved like an accidental transcription enhancer, or "on switch". Because of its sequence, scientists speculate that it mediates estrogen specific regulation, accounting for the high levels of the biliverdin transport protein in the shell gland. Although this story nicely explains our Seussian curiosity about green eggs and ham, it also shows how viruses shape diversity in the living world. For example, an insertion of the avian leukosis virus inside a gene for the enzyme tyrosinase results in white plumage in chickens. Viral insertions can also be incredibly harmful, triggering cancer when they accidentally turn on oncogenes.

    REFS (open access papers): http://goo.gl/3yJ1FS and http://goo.gl/ypZyCF

    Fun Fact: Green Eggs and Ham, published in 1960, is one of the best selling and most beloved children's books of all time. It has just 50 words, and was written by Dr. Seuss in response to a bet by his publisher. 

    Photo: Tammy Riojas, Elgin, TX;

    H/T to +Lorna Salgado for posting the news story that led to this   #ScienceSunday  post. 
  • 303 plusses - 95 comments - 61 shares | Read in G+
  • Rajini Rao2013-09-01 13:33:54
    The Beat Goes On 

    The Cardiomyocyte: Your heart beats about 72 times per minute, or 100,000 times a day, clocking an average of 2.5 billion times in a lifetime and working harder than any other muscle in your body. After all, it has to pump some 2000 gallons of blood around 60 miles of blood vessels each day. No matter how hard you train, the skeletal muscles of your arms or legs could never keep this up. So spare some love for the cardiac muscle cell, or cardiomyocyte

    The Pacemaker: The heart marches to its own tune, unlike the skeletal muscle which gets direct input from a motor nerve. Indeed, the heart would be an unwieldy mess if each individual fiber needed a motor nerve connection.  Instead, every beat of the heart starts within the sinoatrial node (SAN) containing <10,000 pacemaker cells equipped with a built-in clockwork mechanism to fire rhythmically. These electrical impulses spread through the muscle fibers by direct communication from cell to cell via  special channels called gap junctions, that synchronize the contraction. If the pacemaker fails, the ~5 billion working cardiomyocytes don't get their marching orders and the heart slows down or becomes arrhythmic. Promising new research aims to convert ordinary cardiomyocytes to pacemaker cells by expressing a master regulator gene, Tbx18 to replace those lost by disease or defects.

    Sparks and Stripes: Each cardiomyocyte is packed with ordered arrays of thin and thick filaments that slide past each other to make the muscle contract. The thin filaments are made of actin seen as red stripes in the image. The thick filaments are an assembly line of myosin motors that use a rowing motion to pull on the actin filaments. In the absence of an electrical signal, the muscle is relaxed, with the filaments kept apart by a guardian protein called troponin C. The magical molecule that sets the contraction in motion is calcium, seen in the gif as sparks and waves. Each electrical impulse releases a packet of calcium that binds to troponin C, and moves it out of the way to trigger contraction. But the calcium is quickly captured (by calcium pumps and exchangers) and moved back into stores, so the muscle relaxes..before it all begins again.  

    Another installment in the   #excyting series on cell types.
    Adipocyte: http://goo.gl/S4fQFS
    Erythrocyte: http://goo.gl/R5R6Y0
    Astroycte: http://goo.gl/SMpXMV

    REF: Direct conversion of quiescent cardiomyocytes to pacemaker cells by expression of Tbx18. Kapoor et al., 2013 http://www.nature.com/nbt/journal/v31/n1/full/nbt.2465.html

    IMAGE: Composite put together by +Kevin Staff from http://goo.gl/r8wpX8 and  http://goo.gl/1aWsYk . Thanks, Kevin!


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  • Rajini Rao2013-07-06 13:57:32
    A Frondly Challenge!  Banish the moth balls from your brain. Guess the biological identity of this macrophoto.

    Clever Clue: The most sensitive chemical detector known in biology, the object in this image can selectively sniff one molecule in a cubic meter of air.
    How to Play: If you're sure you know what this is, don't give the game away. Instead, contribute some scientific tidbit of information on the topic. Have fun, be creative, the loonier the better ;)

  • 144 plusses - 95 comments - 19 shares | Read in G+
  • Rajini Rao2012-10-18 23:36:57
    It will have blood, they say; blood will have blood - Shakespeare.

    Blood is thicker than water, but it sure does die young. Did you know that the average red blood cell lives not more than 120 days, and 2 million of them die every second?

    Old age and the passage of time teach all things - Sophocles
    The oldest intact human red blood cells were discovered in May 2012 in Ötzi the Iceman, a natural mummy of a man who died around 3255 BCE.

    My love is like a red, red rose - Robert Burns
    Blood is red because of the spectral properties of iron, four of which are attached to each of ~270 million molecules of hemoglobin in each red blood cell. Each iron in heme ferries one molecule of oxygen.

    She got her looks from her father. He's a plastic surgeon - Groucho Marx
    Plastinated blood vessels of the human face are seen at the Human Body exhibition in Ostend, Belgium. Plastination is a technique that replaces water and fat with plastic, to preserve detailed anatomy. Photograph: Francois Lenoir/Reuters

  • 106 plusses - 94 comments - 27 shares | Read in G+
  • Rajini Rao2012-06-21 22:08:00
    CHASING A CHEETAH: The cheetah is the Bugatti Veyron of the animal world, achieving speeds of 29 ms-1 (65 mph), almost twice as fast as their nearest rival, the greyhound. Yet, both have a similar build and use a rotary gallup as opposed to the transverse gallop used by a horse.

    • To chase down the cheetah's secret, researchers buried 8 force plates in an enclosure of UK's ZSL Whipsnade Zoo and tempted the big cats to sprint after a piece of chicken attached to a truck starter motor. Filming at 1000 frames s-1, they measured the forces exerted on the animals' limbs, their body motion and footfall patterns. They did the same with trained greyhounds.

    • The cheetah's stride was slightly longer than the grayhound's. But a striking difference was their ability to change gears: increasing stride frequency from 2.4 strides s–1 at a leisurely 9 m s–1, rising to 3.2 strides s–1 at 17 m s–1. In the wild, they probably reach 4 strides s-1! In contrast, greyhounds maintained a constant stride rate around 3.5 strides s–1 across their entire speed range. Cheetahs also had a longer stance time (length of time the foot stayed on the ground), which is thought to translate to greater acceleration.

    The Cars ~ Dream Away "You better take it on the run, there's a cheetah walking high
    Liquid whispers dragonfly, charleston booties on painted toes"

    REF: Hudson, P. E., Corr, S. A. and Wilson, A. M. (2012). High speed galloping in the cheetah (Acinonyx jubatus) and the racing greyhound (Canis familiaris): spatio-temporal and kinetic characteristics. J. Exp. Biol. 215, 2425-2434.

    Image: http://karook.files.wordpress.com/2008/12/cheetahvelocity.jpg

    Fastest Car: http://www.thesupercars.org/bugatti/2011-bugatti-veyron-super-sport/

  • 118 plusses - 94 comments - 23 shares | Read in G+
  • Rajini Rao2013-11-02 18:06:29
    Diwali: Then and Now

    ⌘ Picture a little girl, shaken awake in the pre-dawn darkness by her mother, shivering before a "head bath" with a pail of steaming hot water from the big copper water heater in the kitchen. Squeaky clean, her hair dried and braided into long mogra flower-laden plaits, she puts on some pretty gold bangles (from an ever-expanding stash of jewelry destined for her future bridal finery) and dresses in a brand new, long skirt of Kanchipuram silk, the traditional and sacred fabric of southern India. After excitedly holding a little sparkler on the balcony, she joins her family for a Diwali feast, full of sweets and special treats that last all day long, while explosions of crackers and the acrid smell of smoke fill the city air.  

    ⌘ Fast-forward many decades later, and the little girl has given up the silks and bracelets for a disciplined life of an academic scientist, transplanted into a distant western land.  It may be Diwali, but she must fly from one coast to another, evangelical in her passion, poring over 200-page reports on the plane and happily rolling polysyllabic words into hour-long lectures. But wait: just before leaving, there is time to whip together a simple family breakfast of beaten rice ("poha") with crunchy, tangy, comforting and colorful notes. Today, the sweetness comes from dimly-recalled memories of childhood and the sparklers are in the bright eyes of the family who will welcome "madamescientist" back home :)  To all those who celebrate, Happy Diwali!

    For +Azlin Bloor, +nomad dimitri and #foodiesdiwali  , with apologies that this is not quite the spread you requested.  

    Recipe:  http://madamescientist.wordpress.com/2013/11/02/diwali-then-and-now/ #diwali  
  • 210 plusses - 92 comments - 5 shares | Read in G+
  • Rajini Rao2012-11-18 20:56:48
    Pods With Pareidolia

    • If you've ever seen a face on a piece of toast, or an animal in the clouds, you've experienced pareidolia (from the Greek para for other and eidos for shape). Carl Sagan proposed that this is a survival technique:  humans are hardwired to instantly recognize faces or familiar objects from seemingly random patterns. Less credible, was the claim by Japanese paleontologist Chonosuke Okamura that fossils from the Silurian period were in fact tiny humans, dinosaurs and other animals. He was awarded the Ig Nobel Prize for his imagination.

    • Does this collection of seed pods trigger a playful pareidolia?

    More reading: http://en.wikipedia.org/wiki/Pareidolia

  • 96 plusses - 92 comments - 42 shares | Read in G+
  • Rajini Rao2012-05-18 12:58:23
  • 110 plusses - 92 comments - 63 shares | Read in G+
  • Rajini Rao2012-11-28 13:58:51
    An Evolutionary Marvel

    • Although birthday girl +Kimberly Chapman will think of +Hugh Jackman,  I must reluctantly clarify that the title refers to the Y chromosome. Yes, that stump of chromosomal appendage endowed with the SRY gene (http://goo.gl/829he). So why the change of heart?

    Alpha Male: Because the Y chromosome carries much less variation than any other chromosome, it was theorized that only a few alpha males (one male for every four females) passed on their genes. This would mean that men have fewer ancestors than women. How does one test this theory?

    Not so skewed: Scientists looked at genetic variations in eight African and eight European men. Then they ran computer simulations with various models of skewed ratios of reproducing males to females over hundreds of thousands of years of evolution. The best fit of data was four females to three males. So why the limited variation in Y chromosome DNA?

    No junk in this trunk: The models showed that evolution weeded out the variation, reducing much of the Y chromosome to highly repetitive strings of letters. One possibility is that this is a clever way of making repairs and preventing the Y from becoming lost altogether. Time will tell.

    Source: http://www.cbsnews.com/8301-205_162-57548588/y-chromosome-an-evolutionary-marvel/

    #HappyBirthdayKim   #ScienceEveryday  
  • 65 plusses - 91 comments - 4 shares | Read in G+
  • Rajini Rao2012-08-30 13:31:54
    Śravaṇa Beḷagoḷa (Kannada: ಶ್ರವಣಬೆಳಗೊಳ): First stop on our three-day trip out of Bangalore, India, this ancient Indian town wedged between two rocky hills, gets its name from a tranquil reservoir (literally, "white tank of the monk"). A barefoot climb up ~650 steps hewn into the granite took us to a 57 foot monolithic statue, carved from a single stone, said to be the tallest of its kind.

    • Nearly 1,800 years old, the statue of the naked Gomateshwara (a Jain monk) is symbolic of renunciation of worldly pleasures. According to legend, the prince Bahubali threw down his weapons after a hollow victory over his brother Bharatha for the throne. Meditating in penance, anthills grew at his feet and vines coiled around his limbs, as seen in the statue. Inscriptions dating back prior to 10th century AD include texts in Kannada, Sanskrit, Tamil, Marathi, Marwari and Mahajani languages. They describe the rise of dynasties of Gangas, Rashtrakutas, Hoysalas and other empires. More on the beautiful carvings of the Hoysala dynasty in my next post.
    • From the hilltop, where a cool breeze rewarded our exertions, we watched school children march in a straggly Independence Day parade with their youthful voices singing the national anthem. A few naked monks strolled nonchalantly past us while my 13 year old remarked that a _namaskara_  (lying prostate at the feet of elders or holy people) might be a "bit dicey" given the view.
  • 121 plusses - 91 comments - 38 shares | Read in G+
  • Rajini Rao2012-06-26 01:15:27
    I wish I was DNA Helicase so I can unzip your Genes: This perfectly legitimate video has been sacrificed to bad internet puns to "celebrate" the trolling of a friend who paid the price of a "What's Hot" post with this come-on, "hello how are you doing today..well i will like to know you more okay so do you have yahoo or msn so we can talk there now okay".

    We were all a-Twitter and played gamely along ("You can come in MySpace anytime", "Do you send HotMail?, "ICQ all the time because you Pinterest me"). So, the next time you get a lame, "HI HOW R U?" (http://goo.gl/DMYZI), feel free to have some pun:

    • Hi, my name's Vista. Can I crash at your place tonight?
    • If I FlickR your YouTube will you Twitter my Yahoo?
    • Can I Ascii you out?
    • I was hoping you wouldn't block my pop-up.
    • Want to see my Red Hat?
    • Mind if I run a sniffer to see if your ports are open?
    • How about we go home and you handle my exception?
    • Hey Baby, let me hack your kernel.
    • You can put a Trojan on my Hard Drive anytime.
    • I wish I was your derivative so I could lie tangent to your curves.

    Keep up the good fight, folks and here's to trolling the trolls!
    Use #trollhelp to call for backup.

    Real Science: Researchers find gold nanoparticles, coated with positive charge, can unzip the two strands of negatively charged DNA. These findings have implications for DNA based electronics or gene therapy. Read more at http://news.ncsu.edu/releases/wms-melechko-dna/
  • 68 plusses - 91 comments - 19 shares | Read in G+
  • Rajini Rao2012-03-10 01:40:28
    Feel Good Friday: 8 am on March 5, 2012. Idyllic blue ocean and ripples of surf. Suddenly, a pod of dolphins appear and beach themselves on this Brazilian coast. Watch the amazingly efficient rescue.
  • 261 plusses - 91 comments - 264 shares | Read in G+
  • Rajini Rao2013-07-30 12:59:15
    Animal, mineral or vegetable? If you can guess the identity of the object in this image, leave a hint or a cool fact in the comments (but try not to give the game away)! 

    Story (and Hint): It was January, 1862 when Charles Darwin first laid eyes on a specimen of the Madagascar orchid Angraecum sesquipedale and exclaimed, "Good Heavens". He went on to predict that an object like the one in this photo would be found. A few years later, Alfred Wallace agreed with Darwin's hypothesis, saying of the orchid, "I maintain...that the laws of multiplication, variation, and survival of the fittest, already referred to, would under certain conditions necessarily lead to the production of this extraordinary XXX". Wallace made a drawing of his prediction, and was proved correct a few decades later.  

    Photo attribution: Steve Gschmeissner
    #ScienceEveryday   #ISeeTheWorldWithScience  
  • 180 plusses - 90 comments - 22 shares | Read in G+
  • Rajini Rao2013-07-21 16:34:34
    Going Rogue : How does a cancer spread to become metastatic?  
    Why do cells that are tightly packed or neatly arranged in rows (epithelia), come loose and become insidiously mobile? The answer lies in a basic developmental process known as EMT, short for epithelial to mesenchymal transition

    ❑ During EMT, cells no longer know which way is up (i.e., lose their polarity), break off their cell-cell junctions and extend pseudopodia or foot-like processes that help them move. In the image below, colon cancer cells were caught in the act of rearranging their junctional proteins (in red and green) to become amorphous, drug-resistant and invasive. Even more dangerous, these cells acquire stem cell properties, allowing them to seed new cancers. In short, cells lose their mature, differentiated form and recapitulate their origins. 

    ❑ But EMT, and its reverse process MET, are normal features of embryo development, leading to formation of the neural tube, heart valve and other organs. Also, during wound healing, skin cells at the edge of the wound undergo EMT, reverting back by MET after the wound is closed. Understanding what triggers these changes, and how they may be controlled, is key to cancer therapy. 

    ❑ This explanation is in response to the more sensationalistic title, New theory uncovers cancer's deep evolutionary roots , shared on G+. The theory "promises to transform the approach to cancer therapy, and to link the origin of cancer to the origin of life and the developmental processes of embryos". Choose between breathless science (http://goo.gl/yDsys) or the rational explanation here :)

    Wiki entry for EMT: http://goo.gl/2U806

    Reference (open access): Chronic oxaliplatin resistance induces epithelial-to-mesenchymal transition in colorectal cancer cell lines. Yang et al. http://www.ncbi.nlm.nih.gov/pubmed/16857785

  • 176 plusses - 90 comments - 57 shares | Read in G+
  • Rajini Rao2012-12-01 14:42:56
    The Guilty Baker: Orange-Cranberry Mini Muffins

    Procrastination inspires industrious bouts of housecleaning, and guilt brings out the baker in me.  I had been flying solo all week, while my husband basked in Florida on some pretext of simulating NASA satellite software (why couldn’t the tests be run in good old Maryland?). By Thursday, I had run ragged with the stress of haranguing my 14 year old out the door and into the school bus by 6:22 am. Dinner degenerated into nachos and guacamole.

    Sharp pangs of guilt (or was it hunger?) gnawed at my maternal conscience as I dawdled over my morning coffee.  When I came across  +claudia lamascolo 's recipe for orange muffins, I decided to face that burden head on. By 8:30 am, a dozen of these little delights were bagged and bound for the lab, while the house smelled of sugar and spice and all things nice. Welcome back, honey. Yes, I’ve been baking and slaving in the kitchen all week. ;)

    The tang of orange zest and cranberries was a delicious counter to the sweetness, with bits of pecan surprise in every other bite. The edges were a bit tough, so I think I will try those frilly paper muffin liners next time. Do you like the cross-stitched napkin? I embroidered the set when I was a pigtailed school girl. My mother saved them for me all these years.  Now that I’ve established my Martha Stewart creds, I hope we can keep that junk food dinner between us, okay?

    Recipe: http://madamescientist.wordpress.com/2012/12/01/the-guilty-baker-orange-cranberry-mini-muffins/
  • 109 plusses - 90 comments - 10 shares | Read in G+
  • Rajini Rao2012-03-12 14:48:18
    True or False? You only use 10% of your brain. This is a popular myth that has been proven false by brain imaging. While not all of the brain is active at the same time, fMRI (functional magnetic resonance imaging) shows widespread activation of the brain for even simple tasks. Take a moment to admire the connectivity of our brain in the image, made by a type of MRI called diffusion spectrum imaging.

    Brain Awareness Week: Today kicks off a global campaign to focus attention on the field of neuroscience, improve public health and outreach by informing on brain research and brain disorders, and to inspire the next generation of scientists. Look for more brain posts and cool neuroscience research all this week!

    Sponsored by The Dana Foundation (http://www.dana.org/brainweek/) and partnered with the Society for Neuroscience (http://www.sfn.org/index.aspx?pagename=baw_home).
  • 151 plusses - 90 comments - 88 shares | Read in G+
  • Rajini Rao2013-03-15 23:06:39
    My Day on the Hill

    This week, several hundred scientists - astronomers, chemists, biologists and engineers from across the nation, descended on Capitol Hill to lobby for science. We asked for sustained and predictable federal funds for scientific research. We voiced our worry that deep cuts in grants would destroy a generation of scientists: that research is not a faucet that can be turned on and off, because the well at the source dries up. We brought a personal face to the projects we were working on.

    What did I learn? Our visit began with a briefing at the AAAS auditorium in Washington, DC. The Office of Science and Technology from the White House gave us the executive branch perspective by breaking down the budget into entitlements and discretionary spending, and showing us the thin slice of pie that went to Federal R&D. Then we got a Congressional perspective from both the House and Senate committees on Science, Space and Technology. These career administrators were scientists themselves, very much "on our side". The next day was a blur of individual visits to offices of senators and congressmen from our states, efficiently organized by the +Biophysical Society whom I was representing. The deal was that we spoke to staffers, and the staffers spoke to the elected members of Congress. We handed out folders full of statistics, talking points and projections. We shook hands, took pictures and exchanged cards.

    Was it worth it? In the long run, yes. Maybe. Like the democratic process, visiting Congress is both our right and responsibility. I left with a better understanding of how Congress runs, and hopefully, made some contacts. It's going to be easier to write to my elected representative the next time I'm called upon to lobby for science.

    Was it fun? Definitely, this was an unforgettable experience. Senate offices are posh! Marbled halls, deep carpeting, brass-studded heavy doors. The House? Not so much. Congress is run by 20-30 somethings: smart but poorly paid, staffers put in long hours and typically don't last more than a year. It was fun to spot faces: there was Sen. Barbara Boxer rushing past us, Rep. John Dingell leaning heavily on his cane, while another senator saw off some fund raisers at his door. 

  • 291 plusses - 89 comments - 17 shares | Read in G+
  • Rajini Rao2012-05-26 23:28:42
    The Dose makes the Poison. A principal concept of Toxicology, first expressed by Paracelcus, an early 16th century physician and alchemist. Did you know that many of your favorite foods naturally contain incredibly potent toxins that can, and have been known, to kill? Not to put you off your potatoes, but here are some infamous poisons found in edible plants.

    Solanine: Never eat potatoes that have turned green because that indicates the presence of solanine, a toxic glycoalkaloid. Although the green color is caused by harmless chlorophyll, solanine is also produced in response to light and is highest just under the skin and in the “eyes” or sprouts. Symptoms range from nausea to death. Although one would need to pig out on green potatoes to die from it, people have been poisoned drinking potato leaf tea. In fact, the Solanaceae family that has also given us our beloved tomatoes, eggplants and tobacco, is chock full of deadly poisons. They include nicotine, atropine and scopolamine. Let’s just say that the genus Atropa (deadly nightshade) is named after the Greek Fate, Atropos, who cut the thread of life.

    Cyanide: More than 500 million people rely on cassava as a source of food, the third most consumed source of starch in the world. Yet, it contains a cyanogen named linamarin, that converts to cyanic acid when eaten. If not processed properly, cassava causes neurological disease and death. On a positive note, the combination of the enzyme linamarase with linamarin could be used to treat cancer in a strategy dubbed suicide gene therapy. Most of the cyanide is produced outside the cells, resulting in a "bystander effect" that kills off the tumor.

    Myrisitin: A psychoactive drug chemically similar to mescaline and amphetamine found in nutmeg and mace. It binds to the brain’s serotonin receptors and causes hallucinations, along with other less pleasant effects. Getting high on nutmeg is teen fad that can be dangerous.

    Phytohaemagglutinin: Causes red blood cells to clump. Found in highest concentrations in raw red kidney beans (also white/cannellini beans), a single bean can have 70,000 haemagglutinating units. As few as five raw beans can bring on nausea, vomiting and worse within a few hours of consumption. This can be reduced by boiling for at least 10 min. However, slow cooking actually increases the toxin levels up to five times! On the bright side, these compounds are useful in research for tracing the connections between neurons, and in medicine, for activating cell division in T-lymphocytes.

    Images: Idaho native +Gnotic Pasta posed for these pictures with the world famous spuds and inspired this post. Many thanks, Dan!

    A G+ Collaboration for +ScienceSunday !
  • 80 plusses - 89 comments - 33 shares | Read in G+
  • Rajini Rao2013-11-24 14:53:16
    Good Fat is BAT!

    Beige, Brite, Brown or White: If you thought all fat was white and wobbly, think again. Some fat depots are colored brown because they are rich in mitochondria- powerhouses of energy loaded with iron-containing cytochrome proteins (bottom panel in image). Beige/Brite fat cells are in between white and brown fat. Human infants have stores of this brown adipose tissue (BAT), up to 5% of their body weight, between their shoulder blades and in their neck, colored green in the MRI scan (top image). Hibernating animals stock up on brown fat too. Why? Because brown fat generates heat.

    The Heat is On: Our mitochondria are factories that extract energy from food and store it in the form of a proton (Hydrogen ion) gradient across their borders. Like water cascading down a fall turns a turbine to generate electricity, this gradient of protons can run downhill through the ATP synthase, propelling it like a motor to capture energy from food by making a chemical compound called ATP. But if these protons ran downhill without doing any work, their potential energy would be lost as heat. The mitochondria in brown fat do just that. They make an uncoupling protein that short circuits the proton gradient to generate heat instead of ATP. This form of thermogenesis is important to newborns and hibernating animals who can't use the shiver reflex to give off heat from their muscles.  

    Better with BAT: Since brown fat burns calories, more BAT could counter obesity, cardiovascular disease and Type 2 diabetes. But adult humans lose most brown fat during adolescence. Fortunately, new studies show that we do have some, mostly deep inside our neck (lower image). One approach to increasing BAT is exposure to cold! Brrr ... if that sounds uncomfortable, stem cells may boost your BAT. Curiously, brown fat cells share a common lineage, not with white fat cells, but with muscle cells. Recent research has revealed the presence of adult stem cells that can be coaxed into active BAT. The hope is to induce these cells to form calorie-burning brown fat in humans. Now that's a healthier browning than a tan!   

    ◑ Images and Refs: (1) Evidence for two types of brown adipose tissue in humans. 
    (2) How brown is brown fat? Depends where you look. Nedergaard and Cannon Nature Medicine 19, 540–541 (2013)

  • 179 plusses - 88 comments - 47 shares | Read in G+
  • Rajini Rao2013-03-11 13:31:38
    Evolution of a Species

    Assortive Mating: The diversity of lifeforms on our planet is central to evolution. But how do new species form? A key step is assortive mating, when individuals use physical or vocal cues to choose mates that resemble themselves. Perhaps natural selection favors offspring from similar matings. Eventually, the populations diverge genetically to the extent that the hybrids are unfit, and separate species emerge.

    Caught in the act? Take the curious case of the Australian Gouldian finch (Erythrura gouldiae). There are black and red head color morphs (see image) that prefer to mate with like types. This preference is genetic, as chicks reared by foster parents of different type still prefer to mate with their own head color morph. In fact, the head color and mating preference are tightly linked on the sex chromosome Z (males are ZZ and females are ZW in birds). This lack of "sexual imprinting" is unusual, since most birds get their cues from rearing parents.

    Hybrid drama: Both head color types coexist in the same geographical area. Shrinking and unequal populations mean that mates of the same type can be hard to find (the bird is endangered). The birds seem to "make the best of a bad situation" and breed with different head color morphs anyway. But there is a steep price to pay : more than a third of the offspring die. The mortality rate is worse in female chicks, nearly half fail to survive. Curiously, the mothers seem to control for this by producing broods with more males. So, if they are tricked into thinking that their mate is of a different head color  (using bird make-up!) they produce biased broods! All of this suggests that the Gouldian finch may be in the process of splitting into species, unless it becomes extinct before then :(

    ▪ Images (National Aquarium): http://aqua.org/explore/animals/gouldian-finch

    ▪ H/T +Mindy Weisberger whose post on the phosphorescence beads marking the gouldian finch chick's mouth (http://goo.gl/Zw8tv) set me off on this evolutionary hunt!

    ▪ Further readings by Sarah R. Pryke ▶ http://goo.gl/Tngj1
  • 191 plusses - 87 comments - 32 shares | Read in G+
  • Rajini Rao2012-11-27 12:12:32
    Beauty is Skin Deep

    What is the largest organ in your body? Not your brain, heart or ..would you have guessed skin? Weighing in at ~3.5 kg, with an area of 2 square meters, your skin accounts for 16% of body weight. About 11 miles of blood vessels and 45 miles of nerves travel through the dermis! 

    Love the Skin You're In: Of your 300 million skin cells, roughly 40,000 are shed every minute. This adds up to ~4 kg/year. The good news is that if you don't like the skin you're in, you'll have a new one in 4 weeks. 

    Don't be Squamish: Skin is layered on as polygonal cells tightly connected into a sheet, known as squamous epithelium. The left image shows the typical cobblestone pattern, with nuclei in blue. 

    Hair Today, Gone Tomorrow: Mammals have a lot of hair, up to 100,000  follicles on our head. The right image is a section through skin showing hair emerging from follicles in the dermis. The dark blue bulge at the base of the follicle is filled with stem cells. 

    Images: http://www.cell.com/cell_picture_show-skin
  • 104 plusses - 87 comments - 30 shares | Read in G+
  • Rajini Rao2014-03-09 22:07:07
    Of Onion Jam and Patriarchal Hegemony

    ◑ What, you may justifiably wonder, does onion jam have to do with the patriarchal hegemony? Nothing, of course. Unless, you count yourself a member of my mad menagerie. Still, if you're looking for some delicious comfort food that's out of the ordinary, and willing to pay a paltry remuneration by nodding sympathetically through my maternal musings, Read On!

    ◑ Like any self-respecting feminist, I yearned for my pragmatic teenage daughter to espouse the cause. More women in STEM! Independence! Equity! So when she won a merit scholarship at one of the Seven Sisters colleges, I exerted my not-inconsiderable persuasive powers to get her to go there. Four years later, she's back, with a degree in neuroscience but somewhat bruised around the edges. Well, the college website did say heady and nervy, and that's what we got. After looking up the patriarchal hegemony on Wikipedia, and nodding every time she said, That's so hetero-normative, I sought a meeting of the minds in the old standby of comfort food.

    ◑ This being the child who asked for caramelized onions as pizza topping and used words like ramekin and macerate in her vocabulary, I turned to a +A French girl "cuisine" for a recipe for onion marmalade (http://goo.gl/jWyAXQ) . The first time we made it, we dutifully converted the metric measures to American. Too bad we didn't follow them. Since then, we've confirmed by innumerable replications (p <0.005) that it always tastes delicious. I served it with a side of penne, baked in a creamy sauce tossed with roasted vegetables and topped with a layer of potatoes. 

    Recipe and More pixhttps://madamescientist.wordpress.com/2014/03/09/of-sweet-onion-jam-and-patriarchal-hegemony/
  • 175 plusses - 86 comments - 12 shares | Read in G+
  • Rajini Rao2012-12-23 17:15:18
    Flowers that Fly: Science of the Butterfly Wing

    Butterflies are beautiful: Their eggs rival Faberge’s for sheer art. The migration of the Monarch butterfly holds navigational secrets still beyond our ken. But the wings are truly remarkable for their mimicry, polymorphism (variation) and aposematism (warning coloration). Like tiny shingles on a roof, microscopic overlapping scales cover the wings with brilliant, iridescent colors.

    Structural Coloration: Black and brown colors are from melanin, but the blues, greens and reds are created by the microstructure of the scales and not by pigments. Originally observed by Robert Hooke and Isaac Newton, the principle of wave interference was described by Thomas Young a century later. Surfaces scored with fine parallel lines or thin layers on the same scale as the wavelength of light reflect multiple sets of waves. These can interfere with one another by adding or subtracting, to give rise to iridescence.
    For more, see: http://en.wikipedia.org/wiki/Structural_coloration

    A Quick Getaway: The scales of a butterfly wing readily detach, allowing for quick escape from a spider’s web or predator’s grasp. Thomas Eisner experimented by dropping various insects on a spider web. Of the butterflies and moths, he noted, “They all left impact marks on the webs where scales became detached to the viscid strands. Moth scars we came to call such telltale sites, and soon learned that they were common." Most birds largely ignore butterflies. It turns out they are rather difficult to catch, without a large net, due to their erratic flying trajectories. Read Thomas Eisner’s essay on Butterfly Wings: http://goo.gl/5Sfon

    • Beauty of the Butterfly Egg: http://goo.gl/0cnas

    • Migration of the Monarch Butterfly: http://goo.gl/WuT6z

    • If you like Opera: Maria Callas (Μαρία Κάλλας): Madama Butterfly - Puccini

    Blue-Butterfly Day by Robert Frost:

    It is blue-butterfly day here in spring,
    And with these sky-flakes down in flurry on flurry
    There is more unmixed color on the wing
    Than flowers will show for days unless they hurry.

    But these are flowers that fly and all but sing:
    And now from having ridden out desire
    They lie closed over in the wind and cling
    Where wheels have freshly sliced the April mire.

  • 235 plusses - 86 comments - 65 shares | Read in G+
  • Rajini Rao2012-08-03 22:10:20
    Gender Bender: How do you tell a man from a woman? The International Olympic Committee has decided to use testosterone levels to decide who can compete as a woman. But it’s not that simple: testosterone levels of elite athletes, both male and female, spread out over a range and overlap as seen in this scatter plot: http://goo.gl/YIKFQ

    • Besides, there are no studies showing that athletes with higher testosterone compete better in sports. Neither is there evidence that response to hormone is the same between individuals. An extreme case is complete androgen insensitivity syndrome. These individuals are chromosomally XY, the normal makeup for men, but their bodies don’t respond to testosterone. So they develop female genitals, but have testes, not ovaries.  South African powerhouse runner Caster Semenya is thought to be one such person. She was banned from competing and then, mysteriously, brought back this year (http://goo.gl/cGyIb). 

    • Half a century ago, the IOC subjected women athletes to “nude parades” before a panel of judges. After realizing that outward appearance can be confounding (as a result of adrenal gland abnormality, for example), they tested for Barr bodies, characteristic of XX chromosomes. But females can have a single X chromosome. This was followed by testing for the SRY gene thought to determine male gender (See my Men! Why U So SRY? post http://goo.gl/VPF0J). But the Atlanta Olympics revealed 8 female athletes who carried this gene, all of whom were eventually allowed to complete.

    • Naturally high testosterone in women is a genetic trait, no different from having more efficient muscles or acromegaly (tallness). So why should some athletes be penalized for this particular trait? Clearly, the goal is to prevent unfair advantage in sports. But it's complicated....

    Image: http://www.nataliedee.com/archives/2010/Apr/

    #london2012 #scienceeveryday  
  • 92 plusses - 86 comments - 24 shares | Read in G+
  • Rajini Rao2012-02-19 14:32:25
    Feast and Famine: Fasting once or twice a week has a beneficial impact on ageing and neurodegeneration.

    Congratulations to +Chris Robinson on getting a science post to the top of "What's Hot" list!

    Reshared text:
    Scientists have known for some time that a low-calorie diet is a recipe for longer life. Rats and mice reared on restricted amounts of food increase their lifespan by up to 40%. A similar effect has been noted in humans. But Mattson and his team have taken this notion further. They argue that starving yourself occasionally can stave off not just ill-health and early death but delay the onset of conditions affecting the brain, including strokes. "Our animal experiments clearly suggest this," said Mattson.

    He and his colleagues have also worked out a specific mechanism by which the growth of neurones in the brain could be affected by reduced energy intakes. Amounts of two cellular messaging chemicals are boosted when calorie intake is sharply reduced, said Mattson. These chemical messengers play an important role in boosting the growth of neurones in the brain, a process that would counteract the impact of Alzheimer's and Parkinson's.
    Science Circles and Helpful Google+ Links: http://goo.gl/i604C
  • 62 plusses - 85 comments - 28 shares | Read in G+
  • Rajini Rao2012-08-28 20:45:39
    Calling on Fanboys, Fandroids and Crackberries: lighten up!  
    The #boycottapple  rage shows no sign of abating on G+. It's become a bore. Do stop, pretty please.  

    Here to amuse, is a survey by Hunch blog on the differences between iOS and Android users. I must say it's spot on: I do prefer a good Malbec to a Shiraz ;)

    Warning: Anyone taking the survey/comic seriously is in dire danger of becoming a bore (or worse, a boor).
    Survey: http://blog.hunch.com/?p=51781
    Image: C-section Comics
  • 80 plusses - 84 comments - 22 shares | Read in G+
  • Rajini Rao2012-11-17 00:24:53
    Battle of the Brains: Size Matters

    Sexual dimorphism, or gender differences in appearance and behavior, arose because selection pressure acts differently on males and females. It is surprising, then, that brain sizes typically do not differ between the sexes in the animal world. Yet, gender differences between selection pressures are common and the brain is one of the most adaptable and plastic organs. Recently, scientists discovered a dramatic difference in brain size among stickleback fish: the male brain is nearly 25% larger than the female, for the same body size and weight amongst fish living in two habitats (mud and lava) of Lake Mývatn in Iceland (see image).

    Bigger is Better: Greater neural mass means greater information processing and superior cognitive power. In animals, larger brains have been shown to coincide with bower complexity in male bowerbirds and with single parenting by females in cichlids. Male sticklebacks build elaborate nests, perform elaborate courtship displays and care for their offspring alone. So guys, pay attention to the nursery if you want to be smarter!

    Delusions of Gender: The costly gain in brain size usually comes with compensation you know where. Male bats trade testis mass against brain mass. Female sticklebacks invest heavily in egg production, which take up 40% of their body weight.  What about humans? Studies showing differences in male and female brains are highly controversial. http://goo.gl/6UVwI  
    Ref: Extreme Sexual Brain Size Dimorphism in Sticklebacks: A Consequence of the Cognitive Challenges of Sex and Parenting? PLoS One. 2012; doi:  10.1371/journal.pone.0030055

  • 76 plusses - 83 comments - 16 shares | Read in G+
  • Rajini Rao2012-07-26 23:30:54
    The Importance of Stupidity in Research: Today, on that other social network, my grad student +Brandie Cross tagged me on this GIF  with the title, "My PI when I try to explain why my experiment failed". I laughed. I was reminded of a wonderful essay by microbiologist Martin Schwartz that made the case for productive stupidity in science. It's great to feel smart, but it's more useful to feel stupid. If you don't feel stupid, are you really pushing the envelope, stretching for that tantalizing little nugget of knowledge seemingly just beyond your reach?

    • Albert Einstein said, "If we knew what it was we were doing, it would not be called research, would it?", which has been loosely parsed as the first law of scientific research: E = Herp Derp^2. The beauty of science is that it is perfectly okay to bumble along , mostly getting things wrong, but being insanely elated when we learn something. The more comfortable we become with being stupid, the deeper we will wade into the unknown and the more likely we are to make big discoveries. Hey, it's not that bad being scorned by the divine Meryl Streep :)

    REF: http://jcs.biologists.org/content/121/11/1771.full
    GIF: "My PI when I try to explain why my experiment failed", http://goo.gl/96ub1
  • 127 plusses - 83 comments - 29 shares | Read in G+
  • Rajini Rao2012-05-04 12:04:51
    FLOWER POWER: The insignificant little plant, Arabidopsis thaliana or thale cress, is a boon to biological research. And even the most ordinary flower looks beautiful through the eyes of a microscope, does it not?

    • Those of us focused on understanding human disease don't pay much attention to research in plants. But plant biologists have taught us about micro RNAs, transposons, active demethylation, 'decoy' RNAs, and more. The wonderful world of genetics was first revealed through the patterns of inheritance of sweet peas, by one Austrian friar named Gregor Mendel.

    • That's why I go to a plant conference once every few years. I never know what I may pick up and plant biologists are gracious enough to listen to our animal work.

    #floralfriday +FloralFriday

    Image: Mendel's Dream Arabidopsis flower captured with confocal microscopy by Heiti Paves, Centre of Excellence ENVIRON, Estonia.
  • 243 plusses - 83 comments - 84 shares | Read in G+
  • Rajini Rao2012-02-17 02:06:02
    Happy Birthday, Ernst Haeckel! German biologist and artist, Haeckel (1834-1919) left his mark in thousands of beautiful, accurate and intricate drawings of life forms at a time before microscopes could take pictures. Did you know that he coined many terms that we take for granted today including ecology , phylum , stem cell and Protista? He is even credited for the first use of the phrase "First World War" to describe the "Great European War" in 1914.

    Flamboyant and passionate, Haeckel was both spectacularly right and completely wrong! He sent his students to Indonesia to look for the remains of ancient humans, resulting in the first human fossil of Pithecanthropus (Homo erectus). He also believed that ontogeny recapitulates phylogeny: that embryos go through stages in development where they resemble lower orders of life. Although junior looked a bit like a fish at one time, but not literally, right? ;)

    Read more about this fascinating scientist: http://en.wikipedia.org/wiki/Ernst_Haeckel
  • 344 plusses - 83 comments - 182 shares | Read in G+
  • Rajini Rao2013-10-27 13:39:28
    A Balancing Act

    Nature's Gyroscope: Your ear does much more than hear. While the snail shaped cochlea of the inner ear (pictured below) is superbly adapted for picking up sound vibrations (by deflections of hair cells described in last week's post), the rest of the inner ear is a complex labyrinth of tubes and chambers that keeps our lives in balance. 

    Up, Side and Down: Since we live in a three dimensional world, we have three fluid-filled semicircular canals arranged at right angles to each other, along the x, y and z planes. Each semicircular canal senses a different movement of our head: up and down, side to side, and tilt. When we move our head, the fluid inside the canal moves and presses on a tear shaped bulb at one end. The bulb (ampulla) has a collection of mechanically sensitive hair cells embedded in a jelly like matrix. Deflection of the "hairs" triggers a message to the balance center of our brain that is interpreted as a deflection of the head. Because we have a pair of ears, the deflections are mirror images so that when one side is stimulated the other is simultaneously inhibited by the movement.  

    Rolling Stones: Two other chambers sense horizontal and vertical accelerations of your body. The saccule detects changes in vertical movement (when you are in an elevator), and the utricle monitors horizontal movement (as when a car suddenly moves forward or stops). While these organs also have mechanically sensitive hair cells, what is different is a special overlaying membrane weighted down with tiny stones of calcium carbonate, around a protein core, called otoconia. A shearing effect of the membrane against the hair cells detects vertical and linear accelerations of your body.  Sometimes, the otoconia fall into one of the semicircular canals (see image) sending conflicting signals to the brain, resulting in vertigo. Fortunately, a series of head maneuvers can restore the rolling stones back into place. Ménière's Disease is a common cause of vertigo, accompanied by hearing loss and tinnitus. It is thought to be caused by disturbances in the fluid volume filling the inner ear. Future relief from vertigo may come from prosthetic devices, similar to a cochlear implant in the inner ear. See Physician Inventors Discuss First Device to Combat Vertigo

    Space Jellies: Did you know that NASA has been sending jelly fish out to space since the 90's for microgravity research? Jellies born in space have trouble orienting and swimming back on Earth because their gravity sensors, crystals of calcium sulfate much like our otoconia, fail to develop properly. Read more: http://goo.gl/Jtj00N

    A follow up on How Hearing Happens: http://goo.gl/lEHKjF

  • 251 plusses - 82 comments - 124 shares | Read in G+
  • Rajini Rao2013-03-07 13:09:22
    Eye See You

    • Fish eyes continue to grow larger throughout their lives because of stem cells that are concentrated at the ends of the red arcs (nerve tissue) seen in this zebrafish eye. This allows the visual cells of the retina to be repaired and regenerated continuously. The retina is seen wrapped around the lens (green circle with black center) in this cross-section.

    • The eye is really an outgrowth of the brain formed during embryo development. Take a look at the orange cells in the eyefield (inset A; ef) pushed to form two lateral bulges by the advancing midline (A-B; blue).

    • Humans (and other mammals) lack stem cells in the adult eye although research is focusing on Müller cells, a type of glial cell that may be able to regenerate neurons and photoreceptors lost to disease and injury.

    Image source: http://bpod.mrc.ac.uk/archive/2013/3/7
    Inset diagram: http://www.ucl.ac.uk/zebrafish-group/research/eye.php
  • 285 plusses - 82 comments - 64 shares | Read in G+
  • Rajini Rao2012-10-04 15:41:20
    Llama Pharma

    Camelid Nanobodies for Therapy: Circulating in the healthy immune system of llamas, camels and alpacas is an unusually small version of antibody- proteins that are key to fighting infection. In contrast to our antibodies that are large and cumbersome (120-150 kilo Daltons in size), single domain antibodies made from the Camelid family are only 12-15 kDa or 4 x 2.5 nanometers in diameter.

    Potent and penetrant, these little proteins (right image) are more soluble and stable than their larger counterparts. They can get deep into tissues or cross the blood brain barrier where they have the potential to neutralize viruses, deliver toxins to cancer cells or even fight fungi in formulations of anti-dandruff shampoo. Concerned about alpaca abuse? No worries, they can be produced in bacterial factories. 

    Sources: (i) http://bpod.mrc.ac.uk/archive/2012/10/4
    (ii) http://en.wikipedia.org/wiki/Nanobodies
    (iii) Saerens et al., Single-domain antibodies as building blocks for novel therapeutics. http://dx.doi.org/10.1016/j.coph.2008.07.006

  • 64 plusses - 82 comments - 14 shares | Read in G+
  • Rajini Rao2012-06-12 00:29:40
    Beauty of the Butterfly Egg: Insects have been around for at least 300 million years. There are over a million species representing more than half of all known living organisms. In fact, they may account for 90% of all multicellular animals on earth

    • Yet insects abandon their young just about anywhere, leaving them to survive on their own. The secret may be hidden in their eggs: tough, yet varied, insect eggs are camouflaged or flamboyant, colorful or embellished with spines, stripes and helices. This gallery represents just one tiny fraction of diversity in the eggs: they are all butterfly eggs.

    Who knew that a butterfly egg less than 2 mm in size could be so beautiful?

    Source of scanning electron micrographs: http://ngm.nationalgeographic.com/2010/09/insect-eggs/dunn-text

    #sciencesunday #scienceeveryday  
  • 136 plusses - 82 comments - 97 shares | Read in G+
  • Rajini Rao2012-10-09 00:14:32
    Fragrant Fennel

    The lady at the checkout line of the local grocer stared at the stout-bulbed feathery fronds with a mixture of perplexion and annoyance. Guiltily, I explained, "It's fennel". "What do you do with it?",  she countered. She really ought to be on G+, I thought.

    Of course, try out +David Crowley 's hearty winter soup, what else? The goodness of potatoes, cabbage and carrots taken to a higher plane with the fragrance of fennel. I substituted a vegetable broth, allowed my husband to add his secret ingredient (psst, a few drops of Angostura bitters) and topped it off with sundried tomatoes, slivers of jalapeno, ribboned sage from the garden, dashes of pepper (red chilli and black) and grated Parmesan.

    What do you like to do with fennel? :)

    David's Recipe: http://cookingchat.blogspot.com/2012/09/csa-day-potato-and-cabbage-soup.html
  • 83 plusses - 81 comments - 7 shares | Read in G+
  • Rajini Rao2013-01-27 15:51:48
    Ode to Mitosis

    Mitosis is a process
    For One cell to become Two
    There are Four distinct phases
    Happening within You

    First comes Prophase
    The Chromatin strands condense
    They now become visible
    Through a microscope lens

    Next comes Metaphase
    The important Stage Two
    Chromosomes attach to Spindle Fiber
    Using Molecular Glue

    Then comes Anaphase
    It's really quite sad
    Sister Chromatids separate
    To opposite poles- too bad :(

    Finally, it's Telophase
    Nuclear membranes reform
    Spindle fibers disperse
    And Two new cells are born.

    Poem: Playfully plagiarized, willfully altered and spell-checked from the original "reallygoodpoetry" at http://goo.gl/OVTvb

    Images: Gifs from http://infinity-imagined.tumblr.com/page/4
    Watch original movie here: http://goo.gl/7HjG7

  • 286 plusses - 80 comments - 299 shares | Read in G+
  • Rajini Rao2013-09-22 20:15:35
    RIP +Kevin Staff

    I am incredibly sad that +Kevin Staff , my long time collaborator in generating science posts on G+ has passed away. Kevin was much too young to leave us. He was an extraordinarily creative artist who specialized in unique styles of gif conversion. Although we never met, I often emailed him with a link to a movie or YouTube video that caught my eye, asking if he could convert it to a gif for a science post. He unfailingly responded with generosity and patience, often redoing them until I was happy. I used to joke that his turnaround time was so rapid that it put pressure on me to write the darn text!

    Please join me in celebrating his art and his generous spirit.  And in conveying our condolences to his friends and family.

    Here is just a small sampling of Kevin's work, there are too many for me to pick favorites:

    Fastest spring in nature: Vorticella http://goo.gl/Jw4hQk
    Walking heads: kinesin http://goo.gl/amYA3P
    London calling: http://goo.gl/MbY71j
    Chris Pirillo, the science experiment http://goo.gl/YMM3bI  

    Reshared text:
    It is with sadness that I am informing you the death of +Kevin Staff 
    on Thursday, September 12 in Loma Linda, California. 

    He was known by his unique animated gifs. On his posts,  he expressed a passion for Coffee, Photography, Arts, Architecture, Design, Science, motivational quotes and travelling. 

    He will be deeply missed by his family, friends and members of his circles. 

    Please join me for a moment's thought in remembrance of a true gentleman, caring person and wonderful human being. 

    #kevinstaff   #coffee   #animatedgifs   #gifs   #geek  
  • 180 plusses - 79 comments - 3 shares | Read in G+
  • Rajini Rao2013-12-08 15:27:42
    Pedigree Puzzle: Why is there a Gender Bias in Autism?

    Autism Spectrum Disorders are more frequently diagnosed in males than females: commonly four times as often, although that bias climbs to 11:1 in the case of Asperger's syndrome. The underlying reasons are complex and many plausible theories have been proposed. Let's begin by looking at one example of pronounced gender bias in autism, seen in this pedigree chart. A pedigree chart is used by geneticists to track genotypes (such as a particular mutation) and phenotypes (such as appearance of a disease) over many generations of an extended family.  If you've never deciphered one before, this is your chance to figure out what those squares and circles mean! 

    How to Read a Pedigree Chart: To begin, girls are circles and boys are squares - helpfully colorized to pink or blue to fit the stereotype ;) There are four generations in this chart (I-IV), each in a separate row. Offspring from a pair are shown by the T bars: for example, the first pair (now deceased) had four children, two males and two females. One of the females produced the four children shown in generation III. Progeny from three pairs are shown in generation IV. Makes sense so far?

    Linking Genes to Autism: Back to the Science. Researchers monitored the SHANK1 gene in ~2,600 people with autism and ~15,000 "controls". They found a large deletion that wiped out most of one copy of the gene in four people with autism. Three were in the family shown in the pedigree chart. None in the control group had this deletion, so this was a statistically significant difference. In gene speak, we say there is a Copy Number Variation (CNV) in this gene. The Shank proteins act as scaffolds around which the synapse, or junction between nerve cells, is built. Other SHANK genes have already been linked to autism, so they used pedigree analysis on SHANK1. Six members of the family carried the CNV but surprisingly, only males with CNV were diagnosed with autism (labeled A in the chart). In case you are wondering, SHANK1 is not on the X chromosome, so the gene is not sex linked. So why are only males in this family autists even though they carry the same mutation as some of the females? This is an extreme case of gender bias in autism. Although the precise answer is not known for the SHANK1 mutation, we will follow some testable hypotheses in future posts! 

    ★ Reference (free read): Shank1 deletions in males with autism spectrum disorder. Sato et al., 2012
    Links to my older posts on autism are here:

    The Genetics of Autismhttp://goo.gl/AzTuAX

    Autism Spectrum Disorders from Mechanism to Therapyhttp://goo.gl/y751QH

    A Part of the Puzzle: NHE9 and Autismhttp://goo.gl/YXbOkN


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  • Rajini Rao2013-10-13 13:48:40
    Fiddle-de-dee: The male fiddler crab is a fine example of how evolutionary pressure can select an exaggerated physical trait: while one claw is small and used for feeding, the other is grossly enlarged, reaching up to 2/3 of his body weight! The female has symmetrical, small claws. So, does size matter? 

    Ornament vs. Armament: The large claw of the male fiddler crab is a sexual ornament, like the feathers of a peacock. With it, he waves flirtatiously at the susceptible female, enticing her to his sand burrow. The larger and more conspicuous his claw, the greater his chance at mating success. It is also an effective weapon, used to threaten and wage battles with competing males. But these are competing demands: large and light claws may be waved at lower energy costs, whereas heavy claws with powerful muscles are better in fights. Studies show that claws evolved to optimize fitness in both mating and fighting (REF: http://goo.gl/n00sZa)

    Keeping Up Appearances: In a study performed upon a beach in Zanzibar, Tanzania, scientists tethered a female crab by super-glueing a thread to her carapace and anchoring it to a spike in the sand. If she was viewed by a solo male, a friendly waving at a leisurely pace of 11.5 waves/min ensued. But in the presence of male competition, his waving became more urgent, at 16.5 waves/min! (REF: http://goo.gl/ME1wW5). Watch this little guy seemingly inspired by the Village People :) YMCA crab dance with music

    Honesty is Not the Best Policy: When a male fiddler loses his major claw, he regenerates a new one of similar size but much weaker fighting ability. Studies have shown that the male can bluff his way through fights with the weaker claw, in a form of dishonest signaling. This unfair advantage presumably makes up for the costs of claw regeneration. (REF: http://goo.gl/OQNfB7)

    A Cool Tool: If you think you now know all there is about the fiddler crab claw, consider this. Scientists measured body temperature of fiddler crabs subjected to a heat lamp and showed that the large claw actually acts as a heat sink, allowing the male to cool off more quickly with it. On a hot beach, this advantage may help offset the high energy costs of his exaggerated "male ornament". (REF: http://goo.gl/EpxrUq )

    ✤ GIF:  http://headlikeanorange.tumblr.com/post/49121046623

    #ScienceSunday      #HappyBirthdayHalfPintBuddy 
    Birthday shout-out to +Buddhini Samarasinghe !
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  • Rajini Rao2012-11-22 14:15:06
    Menu for Mars

    Thanksgiving Meal, celebrated 80 million miles from Earth presents a challenge worthy of any chef. Little wonder that NASA's Advanced Food Technology Project, working with Lockheed Martin, has already begun working on the menu for a manned mission to the Red Planet sometime in the 2030's.

    Veggie Loaf No turkey, sorry! Martian food has to have a shelf life of 5 years, and meat products cannot be stabilized that long with current food technology. I hope the astronauts like soy. Oils or granules of concentrated flavors will be encased in tiny beads and coated with a substance that dissolves on contact with saliva. Yum .

    Pinto Bean Pie “Like a pecan pie without the pecans,” says a NASA senior research scientist. Because the pie may taste 30 percent less sweet in space, astronauts on board International Space Station will do taste tests on the five flavors (sweet, sour, salty, bitter, and umami).

     • Recipe NASA's recipe for Space Cornbread Dressing: http://www.space.com/6173-nasa-recipe-space-cornbread-dressing.html

    Video  Watch Commander Kevin Ford aboard the International Space Station show off today's Thanksgiving meal (dehydrated candied yam with marshmallow cream...  mmmm!): http://www.space.com/18569-thanksgiving-feast-in-space-the-menu-video.html

    Source: http://www.wired.com/wiredscience/2012/11/st_thanksgivingonmars/

    #scienceeveryday #thanksgiving2012  
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