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Comment by Dr. Krishna Kumari Challa on March 11, 2017 at 9:15am

Time crystals: New form of matter...

We have heard about three dimensional crystals such as salt, snow flakes etc. Now two groups of scientists have created a new kind of crystals, whose existence was first suggested by Wilczek who proposed time crystals in 2012, while wondering whether certain properties changing in time, rather than in space, could yield new phases of matter,  repeats a pattern across the fourth dimension—time.

Harvard scientists created time crystals from synthetic diamond while a University of Maryland team used charged atoms of the element ytterbium.  Two groups of scientists report that they’ve observed exotic time crystals, systems of atoms whose properties arrange themselves, or “crystallize” in time like the way solids can crystallize in space. The two groups’ vastly different atomic arrangements aren’t perpetual motion machines, weapons, or time travel devices—but their strange behavior sheds light on a whole new class of materials with properties different from any solid, liquid or gas you’ve ever encountered.

An appropriately tuned laser would flip the spins by 180 degrees. A second, identical laser burst would return the spins to their original position.

Any slight shifts to the frequency of the laser pulses would cause the ions spins to rotate by an amount different from 180 degrees. So they would not reach their starting orientation after two bursts from the spin-flip laser.

In a time crystal, the additional laser pulses introduce disorder and interactions, which make the system resilient to shifts in the frequency of the spin-flip laser. So the system cycles through a repeating pattern.

The researcher also verified that the time crystals were a closed system, and thus no energy is lost outside to the world. Also, the matter appears to have property similar to supercomputers.

http://www.nature.com/news/the-quest-to-crystallize-time-1.21595

Comment by Dr. Krishna Kumari Challa on March 7, 2017 at 8:07am

Malaria parasites make human hosts attract mosquitoes...

Malaria parasites produce a chemical that causes infected people to emit odours attractive to mosquitoes. The chemical, HMBPP, stimulates red blood vessels to produce carbon dioxide and volatile compounds. The discovery of the chemical’s role could be key to controlling malaria, a major disease.

The malaria parasite Plasmodium falciparum produces a molecule which makes infected humans emit carbon dioxide and other volatile compounds that attract mosquitoes and help them spread the disease more efficiently, a study has found. 

The molecule, HMBPP, works by stimulating red blood cells, says Ingrid Faye, researcher at the Department of Molecular Bioscience, Stockholm University (SU) and corresponding author of the study, published in Science  (February 9, 2017). 

Comment by Dr. Krishna Kumari Challa on March 6, 2017 at 9:35am

How science is getting attacked...

US government is not alone in questioning the findings of science. In the past five years, the people and government of Germany have turned against nuclear power; Thabo Mbeki, while president of South Africa, denied that human immunodeficiency virus (HIV) causes AIDS; and the Harper administration of Canada forbade its scientists to speak freely about climate change (this went on for nearly a decade), among other examples. Here in the US, a number of prominent politicians deny scientists’ findings that the first years of the 21st century have been the planet’s hottest on record, and that 2014, 2015, and 2016 have each succeeded the previous as the hottest year on record. Of course, denial is a far easier stance for governments to take: Denying global warming means there’s no reason to do anything about it. 

Comment by Dr. Krishna Kumari Challa on March 1, 2017 at 8:41am

A pair of bacterial genes may enable genetic engineering strategies for curbing populations of virus-transmitting mosquitoes.

Bacteria that make the insects effectively sterile have been used to reduce mosquito populations. Now, two research teams have identified genes in those bacteria that may be responsible for the sterility, the groups report online February 27 in Nature and Nature Microbiology.

Wolbachia bacteria “sterilize” male mosquitoes through a mechanism called cytoplasmic incompatibility, which affects sperm and eggs. When an infected male breeds with an uninfected female, his modified sperm kill the eggs after fertilization. When he mates with a likewise infected female, however, her eggs remove the sperm modification and develop normally.

When the researchers took two genes from the Wolbachia strain found in fruit flies and inserted the pair into uninfected male Drosophila melanogaster, the flies could no longer reproduce with healthy females.

D.P. LePage et al. Prophage WO genes recapitulate and enhance Wolbachia-induced cytoplasmic incompatibility. Nature. Published online February 27, 2016. doi:10.1038/nature21391.

J.F. Beckmann, J.A. Ronau and M. Hochstrasser. A Wolbachia deubiquitylating enzyme induces cytoplasmic incompatibility. Nature Microbiology. Published online February 27, 2016. doi: 10.1038/nmicrobiol.2017.7.

Comment by Dr. Krishna Kumari Challa on February 28, 2017 at 7:16am

WHO releases list of world’s most dangerous superbugs

For the first time ever, the World Health Organization has drawn up a list of the highest priority needs for new antibiotics.

The list, which was released 27th Feb., 2017, enumerates 12 bacterial threats, grouping them into three categories: critical, high, and medium.

The full list is:

Priority 1: Critical
1. Acinetobacter baumannii, carbapenem-resistant
2. Pseudomonas aeruginosa, carbapenem-resistant
3. Enterobacteriaceae, carbapenem-resistant, ESBL-producing

Priority 2: High
4. Enterococcus faecium, vancomycin-resistant
5. Staphylococcus aureus, methicillin-resistant, vancomycin-intermediate and resistant
6. Helicobacter pylori, clarithromycin-resistant
7. Campylobacter spp., fluoroquinolone-resistant
8. Salmonellae, fluoroquinolone-resistant
9. Neisseria gonorrhoeae, cephalosporin-resistant, fluoroquinolone-resistant

Priority 3: Medium
10. Streptococcus pneumoniae, penicillin-non-susceptible
11. Haemophilus influenzae, ampicillin-resistant
12. Shigella spp., fluoroquinolone-resistant

http://www.who.int/mediacentre/news/releases/2017/bacteria-antibiot...

 

Comment by Dr. Krishna Kumari Challa on February 28, 2017 at 7:12am

A giant neuron found wrapped around entire mouse brain

3D reconstructions show a 'crown of thorns' shape stemming from a region linked to consciousness.

http://www.nature.com/news/a-giant-neuron-found-wrapped-around-enti...

Comment by Dr. Krishna Kumari Challa on February 27, 2017 at 7:31am

Comment by Dr. Krishna Kumari Challa on February 17, 2017 at 7:16am

When pollution becomes too high to negate the goodness of exercise? A disaster!

Air pollution is just one of the many crises we’re dealing with across the world. The health impact of air pollution continues to astound us and if you’re the health conscious sort, a new study is bound to upset you. It states that some cities are so polluted that 30 minutes of exercise does more harm than good.

The study was published in the journal Preventive Medicine and it used cycling as the sample activity to simulate exercise. The study assumed an average cycling speed of 12-14 kilometres an hour to check its impact on the body. The results are shocking.

http://www.sciencedirect.com/science/article/pii/S0091743516000402

In north Indian cities such as Allahabad and Gwalior, cycling for more than 30 minutes is bad for health, the study said. In New Delhi, one hour is when the 'breakeven point' is reached. If PM2.5 levels are above a certain level, then any kind of outdoor activity could lead to serious health problems even without exercise. It's not hard to see why the effect will be severe on those who run or cycle outdoors in that kind of weather.

The study did use cycling as a way to measure impact of pollution on exercise but it says that the same numbers apply to similar activities such as slow jogging. If you are training for half marathon, you might want to consider alternatives such as training indoors. The report claims that breathing polluted air has been linked with heart disease, stroke, and even some cancers.

Comment by Dr. Krishna Kumari Challa on February 16, 2017 at 7:32am

The threat of invasive species...

Invasive species can devastate ecosystems. They damage crops, clog rivers, threat native animals and cost farmers and homeowners billions of dollars to control each year. People aren’t the only ones suffering: The invaders have been linked to the decline of some four in every 10 endangered or threatened species.

 Since 1800, the rate at which alien species have been reported around the world has skyrocketed, with almost 40% of them discovered since 1970. Not all nonnative or “alien” species are a problem to a particular environment only those that adversely affect the environment, which are known as “invasive.”

Altogether, the scientists found 16,926 records of alien species of plant, mamm..., they report in Nature Communications.

http://www.nature.com/articles/ncomms14435

The introduction of nonnative plants exploded in the 1800s thanks to the growth of globalized trade, and it has remained high ever since. Mammals and fish peaked around 1950. But other groups, including algae, mollusks, and insects rose steeply after 1950, thanks to climate change and the post–World War II wave of global trade. For those plants and animals that can easily stow away in the ballast of ships, there is a strong correlation between the spread of nonnative species and the market value of goods imported into each region.

How can we control them? Biosecurity and quarantine measures have worked for some more obvious taxa, so we know we can take actions that have positive outcomes. Conservationists hope that better awareness of the threats of species, coupled with improved global biosecurity, will continue to slow the spread of nonnative species. Some researchers predict the rate of spread will reach a saturation point before tailing off. Unfortunately, recent data suggest that may be a long way off.

Comment by Dr. Krishna Kumari Challa on February 13, 2017 at 6:50am

New artificial pollinators!

With bee population getting dwindled in some areas of the world, pollination is becoming difficult endangering agricultural production. But now scientists have found a solution! 

Sticky, insect-sized drones could act as pollinators

Japanese scientists have developed tiny insect-sized drones coated with horse hair and a sticky gel that may help pollinate crops in future and offset the costly decline of bee populations worldwide.

The undersides of these artificial pollinators are coated with horse hairs and an ionic gel just sticky enough to pick up pollen from one flower and deposit it onto another.

“The findings, which will have applications for agriculture and robotics, could lead to the development of artificial pollinators and help counter the problems caused by declining honeybee populations,” said Eijiro Miyako, a chemist at the National Institute of Advanced Industrial Science and Technology (AIST) Nanomaterial Research Institute in Japan.

“We believe that robotic pollinators could be trained to learn pollination paths using global positioning systems and artificial intelligence,” said Miyako.

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