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Sunil Bajpai
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Science Mystery Pix

Stomatal pores under a leaf? Sand dunes on Mars? Clams clamoring to be fed? Hint: the image illustrates an evolutionary adaptation. Take a guess, then read on!

Secret of Serotiny: In 1961, a fire destroyed 28,000 acres of forest in Montana. Since then, the lodgepole pine has established dominance over this vast acreage, with a density of tens of thousands of trees per acre. Yet, this pine normally does not spread its seed beyond a range of some 200 meters. How did the lodgepole pine achieve this remarkable biotic potential?

Its secret was serotiny: millions of seeds per acre were stored inside cones, high up at the canopy top of mature stands, for just this scenario. The heat of the fire melted the resin that kept the cones closed, releasing seeds to be carried by wind or gravity over several days, to land on burned but cooling ground. With little competition, more light, warmth and nutrients from ash, the seedlings flourished, making this pine an aggressive pioneer species.  

Serotiny is the adaptation by some plants that hold on to their seeds for decades after they are mature, releasing them only in response to a specific environmental trigger. The trigger could be dryness, water, or fire. Some desert plants have adapted to release seeds after rainfall, when the chances of successful germination are high. Other plants release seeds only after they die, a feature known as necriscence. Oddly, fire-survival strategies may be paired with fire-embracing adaptations, such as retaining dead (and flammable) branches instead of the more common practice of self pruning . Known as niche construction, this double strategy ensures removal of poorly adapted plants in regions susceptible to natural fires. 

The Fiery Cretaceous: Fire has been an effective agent of natural selection for at least 125 million years and possibly longer! The high oxygen levels (23-29% compared to today's 21%) in Earth's paleoatmosphere of the early Cretaceous fueled frequent fires, captured as charcoal in the fossil records. Since then, fire adapting traits in plants arose independently, many times.  Our Mystery Pix can now be revealed as the cone of a Banksia tree, endemic to Australia, with open seed pods after a bushfire. Photo via PinkRockAus's Fotothing http://goo.gl/ZEfDHm
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Why hasn't there been post from +Max Huijgen​ for more than 6 months?

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Herbal Cancer Cure: Weeding out the Hype

A recent G+ post (https://goo.gl/pGDJUZ) claimed that artemisinin, derived from an ancient Chinese herb Artemisia annua, kills 98% of lung cancer cells in less than 16 hours. What's wrong with this claim?

◈ The comments fell into two categories: some outright disbelief If this is factual, it'd be amazing and More pseudoscience, Geesh! More common were conspiracy theories from the predictable, The W.H.O., F.D.A., C.D.C., etc. Can't patent it, so they can't make money off of it. to the bizarre, Funny thing is that the government gets their money off of cancer so I wonder if they'll make this illegal and claim it's got a side-effect that makes people experience what they would if they used Marijuana. Idk, but the government's gonna F it up somehow. Let's examine the claims and counterclaims. 

98% of cancer cells are killed by artemisinin.....in a culture dish! It's easy to kill cells in a dish -just ask my students :) These are in vitro findings. How about in vivo? Experiments done in rodents are indeed promising and have been reviewed and reported. Unfortunately, we scientists are excellent mouse doctors, and many drugs that cure cancer in mice under controlled, ideal lab conditions fail in the clinic. Does it work on humans? There are a few case reports of using artemisinin in humans. But, these are anecdotal and of limited use, since the patients were under chemotherapy anyway. What is needed are large scale randomized clinical trials with placebo controls to check if this herb is effective against cancers. Such trials cost a billion dollars and have not yet been done. 

Artemisinin has been safely tested in over 4000 patients...this claim from a doctor in a popular video (https://youtu.be/_Or8xLOGBu8) probably refers to a Phase I trial where only safety is monitored. Notice the doctor does not say if the herb was effective against cancer in these 4000 patients. 

The FDA will never approve it....wrong, because it is already an FDA-approved antimalarial drug. In fact, artemisinin in combination with other drugs is the gold standard for treatment of Plasmodium falciparum malaria worldwide. The WHO has negotiated with Novartis and Sanofi-Aventis to obtain the drug at cost, with no profit. 

Bottom line: Both sets of comments are off the mark! The potential of artemisinin as a cancer chemotherapeutic should not be dismissed as pseudoscience until proven otherwise. As for the conspiracy theorists, they're just wrong.

Wiki: https://en.wikipedia.org/wiki/Artemisinin #OpenAccess REF: Anticancer Effect of AntiMalarial Artemisinin Compounds. (2015) Das, AK http://www.ncbi.nlm.nih.gov/pubmed/25861527

#ScienceSunday  
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The Greening of Greenhouse Gas

It's a Gas: Driving through the Western Ghat mountains along the continental edge of the Deccan Plateau, I was charmed by this vista of sculpted terraces with verdant blades of rice emerging from submerged paddy fields. Little did I know then that paddy fields generate 50-100 million tonnes of methane each year, a potent greenhouse gas with 25 times the heat trapping potential of carbon dioxide. Although the flooded fields keep weeds at bay, microbes harbored under the warm, waterlogged soil feed on organic matter exuded by roots, releasing methane and accounting for about 20% of human-related production. In China, farmers have begun draining fields mid-season to interrupt methanogenic bacteria. But India is still responsible for nearly a third of the methane emissions. 

It's Barley There: Now, thanks to genetic engineering, a new strain of rice yields more grain and produces less methane. Researchers spliced a gene from barley, encoding a master regulator (transcription factor) into rice. The gene, dubbed SUSIBA2 (acronym for "sugar signaling in barley 2") increases the output of sugar and starch in the seeds, leaves and shoots of the rice plant, leaving less biomass in the root. This strongly decreased the methanogenic bacteria in the rhizosphere, or region around the root. In a 3-year field trial, methane emissions fell by 90%.

Rice, Rice, Baby: The making of starch is under the direction of a set of genes which carry in front of them stretches of DNA sequences (promoters) known as sugar responsive elements or SURE. Aren't you loving the acronyms? When a little bit of sugar is made, SUSIBA2 is activated and it turns on genes that make even more sugar, to create a snowballing effect. The sugar is converted to starch, diverting carbon to the grains and away from the root, starving the methane producing bacteria of food. Now that's a sweet way to cool down our planet!

This work was a collaboration between scientists at Universities and non-profit research Institutes in Sweden, China and the US. The authors have no competing financial interests. 

Paper (paywalled): http://www.nature.com/nature/journal/v523/n7562/full/nature14673.html 

#ScienceSunday  

 
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2015-08-02
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#Appreciation
Your appreciation goes a long way in motivating us in delivering better services.  One such compliment received this morning at Thrissur Railway Station. We express our sincere thanks to Ms. Lissiue Flower Antony for taking time to pen down few words.
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