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Comment by Dr. Krishna Kumari Challa on July 5, 2017 at 7:10am

Praying mantises are posing threat  to small birds...

A study by zoologists from Switzerland and the US shows: praying mantises all over the globe also include birds in their diet. The Wilson Journal of Ornithology has just published the results.

he researchers gathered and documented numerous examples of bird-eating mantises. In a systematic review, they were able to show that praying mantises from twelve species and nine genera have been observed preying on small birds in the wild. This remarkable feeding behavior has been documented in 13 different countries, on all continents except Antarctica. There is also great diversity in the victims: birds from 24 different species and 14 families were found to be the prey of mantises. "The fact that eating of birds is so widespread in praying mantises, both taxonomically as well as geographically speaking, is a spectacular discovery," comments Martin Nyffeler from the University of Basel and lead author of the study.

http://www.bioone.org/doi/10.1676/16-100.1

Comment by Dr. Krishna Kumari Challa on July 5, 2017 at 7:06am

Researchers have found material that removes synthetic pollutant dyes from water...

Researchers from Energy Safety Research Institute (ESRI) at Swansea University, U.K hold the key to the problem in the form of a novel, non-hazardous photocatalytic material.

The said material effectively removes dye pollutants from water, adsorbing more than 90 % of the dye and enhancing the rate of dye breakdown by almost ten times using visible light. The composite material as a combination of tungsten oxide and tantalum nitride, also provides a huge surface area for dye capture, being less than 40 billionths of a metre in diameter. The material was synthesized by heating the reaction mixture at high pressures inside a sealed container which involved growing ultra-thin “nanowires” of tungsten oxide on the surface of tiny particles of tantalum nitride. It further proceeded to break the dye down into smaller, harmless molecules using the energy provided by sunlight, in a process known as ‘photocatalytic degradation’. 

Having removed the harmful dyes, the catalyst can be simply filtered from the cleaned water and reused. Due to the exchange of electrons between the two materials, the test dye used within the study was broken down by the composite at around double the rate achieved by tantalum nitride on its own, while tungsten oxide alone was shown to be incapable of dye degradation.

The research is published in the journal Scientific Reports.

Comment by Dr. Krishna Kumari Challa on June 28, 2017 at 6:37am

Bad news for coral reef lovers...the 3 successive years of bleaching conditions damaged all but three of the 29 reefs that are or are contained within United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage sites. And the prognosis is grim: Without dramatic reductions in greenhouse gas emissions, all these reefs "will cease to host functioning coral reef ecosystems by the end of the century," predicts the report from UNESCO’s World Heritage Center in Paris.

Feel sad, because I love corals :(

Comment by Dr. Krishna Kumari Challa on June 24, 2017 at 7:30am

Comment by Dr. Krishna Kumari Challa on June 24, 2017 at 7:00am

Comment by Dr. Krishna Kumari Challa on June 24, 2017 at 6:01am

Hormones made by brain...

Bones give us structural support to out bodies. We all know that. Apart from that function, bones also make hormones. Do you know this fact?

Yes, there’s so much going on between bone and brain and all the other organs, it has become one of the most prominent tissues being studied at the moment.

At least four bone hormones found working in living systems, recent studies show, and there could be more. Scientists have only just begun to decipher what this messaging means for health. But cataloging and investigating the hormones should offer a more nuanced understanding of how the body regulates sugar, energy and fat, among other things.

Of the hormones on the list of bones’ messengers — osteocalcin, sclerostin, fibroblast growth factor 23 and lipocalin 2 — the last is the latest to attract attention. Lipocalin 2, which bones unleash to stem bacterial infections, also works in the brain to control appetite, physiologist Stavroula Kousteni of Columbia University Medical Center and colleagues reported in the March 16 Nature.

After mice eat, their bone-forming cells absorb nutrients and release a hormone called lipocalin 2 (LCN2) into the blood. LCN2 travels to the brain, where it gloms on to appetite-regulating nerve cells, which tell the brain to stop eating, a recent study suggests.

Geneticist Gerard Karsenty of Columbia University Medical Center found that osteocalcin — made by osteoblasts — helps regulate blood sugar. Osteocalcin circulates through the blood, collecting calcium and other minerals that bones need. When the hormone reaches the pancreas, it signals insulin-making cells to ramp up production, mouse experiments showed. Osteocalcin also signals fat cells to release a hormone that increases the body’s sensitivity to insulin, the body’s blood sugar moderator, Karsenty and colleagues reported in Cell in 2007. If it works the same way in people, Karsenty says, osteocalcin could be developed as a potential diabetes or obesity treatment.

Comment by Dr. Krishna Kumari Challa on June 23, 2017 at 7:13am

Comment by Dr. Krishna Kumari Challa on June 23, 2017 at 6:41am

Metagenomic sequencing study:

The test is the brainchild of researchers at the  University of California, San Francisco, led by neurologist Michael Wilson, biochemist Joseph DeRisi and infectious disease expert Charles Chiu. The group uses genetic-sequencing technology to identify mystery illnesses in people with encephalitis or meningitis (inflammation of the meninges, the membranes around the brain and spinal cord). This so-called metagenomic test analyzes all the DNA and RNA found in a sample of cerebrospinal fluid (meta means “beyond” in Greek). So any DNA or RNA that does not belong to the patient—including that from viruses, bacteria, parasites or fungi—shows up in the results.

Done correctly, metagenomic testing could radically change the way infections of the brain are diagnosed. An element of circular logic underlies most standard infectious disease tests. Doctors order individual tests for each bug they suspect might be causing the problem. But how do they know what is causing the problem if they have not yet done the test? Metagenomic sequencing, in contrast, casts the broadest possible net, which allows it to pick up unexpected or previously unknown pathogens. Scientists and doctors are looking at everything at once, which has the potential of replacing the myriad of lab tests with a single test.

Genetic sequencing of Cerebro-spinal fluid hailed as an advance over standard procedures for diagnosing brain infections

Comment by Dr. Krishna Kumari Challa on June 21, 2017 at 9:41am

Potent Inhibitor of Drug-Resistant HIV-1 Strains Identified from the Medicinal Plant Justicia gendarussa

Justicia gendarussa, a medicinal plant collected in Vietnam, was identified as a potent anti-HIV-1 active lead from the evaluation of over 4500 plant extracts. Bioassay-guided separation of the extracts of the stems and roots of this plant led to the isolation of an anti-HIV arylnaphthalene lignan (ANL) glycoside, patentiflorin A (1). Evaluation of the compound against both the M- and T-tropic HIV-1 isolates showed it to possess a significantly higher inhibition effect than the clinically used anti-HIV drug AZT. Patentiflorin A and two congeners were synthesized, de novo, as an efficient strategy for resupply as well as for further structural modification of the anti-HIV ANL glycosides in the search for drug leads. Subsequently, it was determined that the presence of a quinovopyranosyloxy group in the structure is likely essential to retain the high degree of anti-HIV activity of this type of compounds. Patentiflorin A was further investigated against the HIV-1 gene expression of the R/U5 and U5/gag transcripts, and the data showed that the compound acts as a potential inhibitor of HIV-1 reverse transcription. Importantly, the compound displayed potent inhibitory activity against drug-resistant HIV-1 isolates of both the nucleotide analogue (AZT) and non-nucleotide analogue (nevaripine). Thus, the ANL glycosides have the potential to be developed as novel anti-HIV drugs.

http://pubs.acs.org/doi/abs/10.1021/acs.jnatprod.7b00004

Comment by Dr. Krishna Kumari Challa on June 17, 2017 at 9:10am

Quantum communication...

A successful quantum communication network will rely on the ability to distribute entangled photons over large distances between receiver stations. So far, free-space demonstrations have been limited to line-of-sight links across cities or between mountaintops. Scattering and coherence decay have limited the link separations to around 100 km. Yin et al. used the Micius satellite, which was launched last year and is equipped with a specialized quantum optical payload. They successfully demonstrated the satellite-based entanglement distribution to receiver stations separated by more than 1200 km. The results illustrate the possibility of a future global quantum communication network.

http://science.sciencemag.org/content/356/6343/1140

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Scientists have solved a centuries-old mystery of "bright nights" - an unusual glow that appears in the sky after dark and lets observers see distant mountains, read a newspaper or check their watch.

Researchers suggest that when waves in the upper atmosphere converge over specific locations on Earth, it amplifies naturally occurring airglow, a faint light in the night sky that often appears green due to the activities of atoms of oxygen in the high atmosphere.

Normally, people do not notice airglow, but on bright nights it can become visible to the naked eye, producing the unexplained glow detailed in historical observations.

Modern observations of bright nights from Earth are practically nonexistent light pollution. Even devoted airglow researchers have never seen a true bright night.

However, even before the advent of artificial lighting, bright nights were rare and highly localised.

Researchers could see bright night events reflected in airglow data from the Wind Imaging Interferometer (WINDII), an instrument once carried by NASA's Upper Atmosphere Research Satellite (1991-2005).

They searched for mechanisms that would cause airglow to increase to visible levels at specific locations.

Airglow comes from emissions of different colors of light from chemical reactions in the upper reaches of the atmosphere. The green portion of airglow occurs when light from the sun splits apart molecular oxygen into individual oxygen atoms.

When the atoms recombine, they give off the excess energy as photons in the green part of the visible light spectrum, giving the sky a greenish tinge.

To find factors that would cause peaks in airglow and create bright nights, researchers searched two years of WINDII data for unusual airglow profiles.

They identified 11 events where WINDII detected a spike in airglow levels that would be visible to the human eye, two of which they describe in detail in the study.

Finally, the researchers matched up the events with the ups and downs of zonal waves, large waves in the upper atmosphere that circle the globe and are impacted by weather.

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