Science Simplified!

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Comment by Dr. Krishna Kumari Challa on February 12, 2015 at 9:04am

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Comment by Dr. Krishna Kumari Challa on February 12, 2015 at 8:55am

Science is like magic! Watch the wonder of it!

The experiment is also surprisingly simple to replicate at home. All you need is some sand and some water-repellant spray, such as Scotchgard (or gotchscard, which you'll understand when you see the clip above). You spread the sand out and then give it a couple of genorous coatings of water-repellant chemicals. Once it's dry, you're now the proud owner of hydrophobic sand.

You can also even buy hydrophobic sand, called Magic Sand, that's pre-made, and contains ordinary beach sand mixed with tiny particles of silica. The combination is then exposed to vapours of trimethylsilanol, an organosilicon compound, that bonds to the silica particles, creating a hydrophobic coating for the sand.

Both Magic Sand and the DIY hydrophobic variety will do anything it can to avoid contact with liquid, including forming strange formations underwater to reduce surface area.

Comment by Dr. Krishna Kumari Challa on February 11, 2015 at 9:22am

How to tell whether people got enough sleep or not

A drop in certain fats and acids in the blood may reveal whether a person is critically sleep deprived, scientists report online February 9 in Proceedings of the National Academy of Sciences. When people and rats skimp on slumber, two compounds involved in metabolism become depleted.

A reliable marker of sleep debt could be used to test whether pilots, truck drivers and other people who hold jobs with long hours are sufficiently well rested, says coauthor Amita Sehgal, a neuroscientist at the University of Pennsylvania.

Going without sleep blunts people’s performance on memory and attention tests, and has been linked to diabetes, heart disease and other illnesses. To see how losing sleep changes metabolism, Sehgal and her colleagues took blood samples from rats and humans after they’d had only four hours of sleep a night for five nights.

In both species, two molecules involved in metabolism decreased. One is a fat that plays a role in storing energy and helping hormones send messages. The other, an acid, is a by-product of normal metabolism. Levels of both molecules bounced back after a full night’s sleep.

Sehgal and her colleagues will keep investigating these metabolic effects of sleep loss. “We’re seeing these changes in the blood, but where are they coming from and how do they relate to what’s happening in the liver, the adipose [fatty] tissue, the muscle?” Sehgal asks.

http://www.pnas.org/content/early/2015/02/03/1417432112

http://www.pnas.org/content/early/2015/02/03/1417432112

Comment by Dr. Krishna Kumari Challa on February 11, 2015 at 8:29am

How do medical journalists treat cancer-related issues?
http://ecancer.org/journal/9/full/502-how-do-medical-journalists-tr...
Where Do Medical Journalists Find Their Sources? Direct contact with patients and doctors is favored over press releases from pharmaceutical companies, a survey of journalists reveals.
Researchers at the University of Tokyo sent self-administered questionnaires to 364 medical journalists, who described their experiences in selecting stories, choosing angles, and performing research when creating cancer-centerd news pieces. The journalists reported that they did not find pharmaceutical press releases to be helpful, preferring direct contact with physicians as their most reliable and prized sources of information. Medical journalists also report using social media and personal connections to support their research.
All journalists reported difficulties in producing accurate and interesting cancer news stories. The most commonly reported concerns were the quality of source information, difficulty in understanding technical information and a shortage of background knowledge.
As medical knowledge advances rapidly, journalists may have increasing difficulty covering cancer-related issues .
This highlights the need for responsible healthcare reporting, the team suggests, which can be attained through journalistic communication with researchers and physicians, and the willingness of healthcare professionals to explain their work carefully and clearly.
Asian Scientist Magazine : http://www.asianscientist.com/2015/02/in-the-lab/medical-journalist...

Comment by Dr. Krishna Kumari Challa on February 11, 2015 at 8:22am

Researchers have succeeded in inducing human embryonic stem cells to self-organize into a three-dimensional structure similar to the cerebellum, providing tantalizing clues in the quest to recreate neural structures in the laboratory. Their results have been published in Cell Reports.

Full details here:

 Muguruma et al. (2015) Self-Organization of Polarized Cerebellar Tissue in 3D Culture of Human Pluripotent Stem Cells.

http://linkinghub.elsevier.com/retrieve/articleSelectPrefsTemp?Redi...

Comment by Dr. Krishna Kumari Challa on February 11, 2015 at 8:17am

So you think as your original age is just 31, you are likely to live another 40-50 years without any doubt. Is your thinking right ? Not necessarily according to new research.
"DNA methylation age of blood predicts all-cause mortality in later life"
We count our age in calendar years, but our bodies may not be counting the same way. Using a biological clock that compares the aging of a person’s DNA to their actual age, University of Queensland researchers have found some clear signals to life expectancy. Professor Naomi Wray, from UQ’s Queensland Brain Institute (QBI), said the study found that people with a “biological” or DNA age greater than their true age were more likely to die younger, compared to those whose biological and true age were closely matched. “Last year, it was discovered that from a simple blood sample it is possible to predict a person’s age with a high degree of accuracy,” Wray said. “But it is not totally accurate, and some people’s predicted or ‘biological’ age is higher than their actual age and vice versa.” “Our study showed biological age really does seem to be tracking biological wear-and-tear.” The study, published in Genome Biology, used data from four independent studies that sampled almost 5,000 older people, of whom about 10 percent died in the following 14 years. Each participant’s biological age was measured from a blood sample at the outset. The research showed that those with a higher biological age compared to actual age had an increased risk of death. All four studies found the same pattern, with death linked to accelerated biological changes to DNA. Wray said the study could not look at what caused the DNA to change at an accelerated pace, nor was it an accurate predictor of death for an individual person. “However, it’s an important clue for future research in the study of cellular ageing,” she said. “What we’re seeing could be caused by environmental, lifestyle, genetic predispositions, or a combination of all these factors.” The QBI’s Dr. Allan McRae, who conducted analyses for the study, said biological ageing was measured by following DNA changes caused by a process known as methylation. “Methylation affects whether genes are turned on or off, which has important repercussions for conditions such as disease susceptibility, so it makes sense that the biological clock speeding up has impacts on how we age,” McRae said.
http://genomebiology.com/2015/16/1/25/abstract

Comment by Dr. Krishna Kumari Challa on February 11, 2015 at 8:04am

For Precision, Two Clocks Are Better Than One The optical lattice clocks use lasers to create “egg box” structures that contain single atoms, leading to unprecedented precision.
Cryogenic optical lattice clocks
http://www.nature.com/nphoton/journal/vaop/ncurrent/full/nphoton.20...

Comment by Dr. Krishna Kumari Challa on February 11, 2015 at 6:18am

Efficient solar-to-fuels production from a hybrid microbial–water-splitting catalyst system

A new way to make fuel from sunlight: starve a microbe nearly to death, then feed it carbon dioxide and hydrogen produced with the help of voltage from a solar panel. A newly developed bioreactor feeds microbes with hydrogen from water split by special catalysts connected in a circuit with photovoltaics. Such a batterylike system may beat either purely biological or purely technological systems at turning sunlight into fuels and other useful molecules.
http://www.pnas.org/content/early/2015/02/06/1424872112

Comment by Dr. Krishna Kumari Challa on February 9, 2015 at 7:12am

This sea slug ‘feeds’ on sunlight using photosynthesis

Part flora, part fauna, this pretty green sea slug has gained the ability to photosynthesise by stealing genes from the algae it feeds on.
After decades of searching, scientists have finally found direct evidence to show that the emerald green sea slug (Elysia chlorotica) takes genes from the algae it eats to perform photosynthetic processes, just like a plant. This means it can get all the energy it needs from sunlight, allowing it to survive without food for months.

“There is no way on earth that genes from an alga should work inside an animal cell”. And yet here, they do. They allow the animal to rely on sunshine for its nutrition. So if something happens to their food source, they have a way of not starving to death until they find more algae to eat.

Scientists have known for over 40 years that the emerald green sea slug takes chloroplasts - organelles found in plant and algal cells that facilitate photosynthesis - from the yellow-green algae it eats, called Vaucheria litorea. Referred to as ‘kleptoplasty’, this process allows the chloroplasts to continue photosynthesising in their new sea slug home for up to nine months after transferring from the algae. By photosynthesising, the sea slug produces lipids when the energy from the sunlight is combined with water and carbon dioxide, which gives it all the nourishment it needs, no additional food required.
But exactly how the emerald green sea slug manages to maintain these organelles in working order for so long has proven to be a complex puzzle - one that was not made easier by an experiment completed by researchers at the University of Dusseldorf in Germany in 2013. The team gave their emerald green sea slugs a drug that completely halted any photosynthetic activity in their cells, but the slugs still managed to survive for 55 days, without any food. They ended up a little smaller and paler, so food wouldn’t have gone astray if they were offered it, but it was proof that the organelles they 'stole' from their last algae meal were somehow still working for them.
"In order to photosynthesise, the chloroplasts inside an alga depend on many genes in the alga’s own nucleus and the proteins for which they code. Tearing chloroplasts out of algal cells and asking them to make food inside a slug’s gut is like expecting the bottom half of a blender to puree some carrots sans the blade and glass jar.”

So where are these genes that the chloroplasts depend on? Reported in The Biological Bulletin, fluorescent DNA markers were used to track the genes from the algae as they made their way into the genetic material of both juvenile and adult emerald green sea slugs. And for the first time, the research team watched as these genes produced an enzyme that’s critical to the proper photosynthetic function of the chloroplasts.

“This paper confirms that one of several algal genes needed to repair damage to chloroplasts, and keep them functioning, is present on the slug chromosome. The gene is incorporated into the slug chromosome and transmitted to the next generation of slugs.”

So while the young emerald green sea slugs still need to feed on the algae to get their supply of chloroplasts, the genes they need to turn these chloroplasts in to little photosynthetic machines have already been passed down to them from their parents.

"Importantly, this is one of the only known examples of functional gene transfer from one multicellular species to another, which is the goal of gene therapy to correct genetically based diseases in humans.
Sources: The Marine Biological Laboratory Blog, Scientific American, Smithsonian.com

Comment by Dr. Krishna Kumari Challa on February 9, 2015 at 7:03am

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