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Comment by Dr. Krishna Kumari Challa on July 21, 2016 at 8:34am

A research project led by The Australian National University (ANU) has closed an important gap in the understanding of a fundamental process of life -- the creation of proteins based on recipes called RNA.

RNAs are short-lived copies of genetic information stored in DNA. They are read by cellular ribosomes, which translate the recipes into proteins to become the main building blocks of life.

Lead researcher Professor Thomas Preiss from The John Curtin School of Medical Research (JCSMR) at ANU, said the new understanding would open up avenues for treatment of a wide range of diseases including cancer, heart disease and a spectrum of rarer genetic diseases.
The research team took snapshots of how ribosomes distribute along the RNA strings, paying particular attention to how ribosomes make sure they read the recipe from the correct starting point.

Cells throughout the body contain the same complete blueprint for life in their DNA.

"To create and maintain cells as diverse as those in the brain, bone or liver requires great precision in terms of which RNA recipes are made available, where and when.
How efficiently and accurately ribosomes read and translate the recipes is also critical.

For example, ribosomes are known to become over-active in cancer.
The research confirms a 40-year-old theory that explains how the ribosome correctly picks up the beginning of the code, even though the code usually only begins some distance inside the RNA string.
Research team member Dr Nikolay Shirokikh from ANU said the project examined where the two components of the ribosome started to attach to RNA strings.

"The theory was that the smaller half of the ribosome attaches itself to the very beginning of the RNA and then scans along the string until it finds the start signal of the recipe. There, the larger half joins and the whole ribosome begins to manufacture a protein," Dr Shirokikh said.

"Our ribosome snapshot approach has finally provided proof that the scanning model is correct. We also gained new insight into how fast the ribosome can complete the different tasks and how other cellular components come in to help it along."
The ribosome snapshot data generated with the new technique was made available to scientists globally via an app for high-content data visualisation developed at the Monash Bioinformatics Platform.
The research has been published in the journal Nature.
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature18647...

Comment by Dr. Krishna Kumari Challa on July 17, 2016 at 10:51am

Species Biodiversity has fallen below 'safe' level on majority of land on Earth, a recent study reported in Science  says. 

Each year humans use more land for buildings, roads, industries and agriculture purposes. That may not always cause extinctions, it does reduce the number of species within specific ecosystems. When bio-diversity drops too low ecosystems can loose their resilience and even stop functioning.

 In many parts of the world, we are approaching a situation where human intervention might be needed to sustain ecosystem function, according to the study. 

Biodiversity intactness within most biomes (especially grassland biomes), most biodiversity hotspots, and even some wilderness areas is inferred to be beyond the boundary. Such widespread transgression of safe limits suggests that biodiversity loss, if unchecked, will undermine efforts toward long-term sustainable development.

The greatest changes have happened in those places where most people live, which might affect physical and psychological wellbeing. To address this, we will have to preserve the remaining areas of natural vegetation and restore human-used lands

http://science.sciencemag.org/content/353/6296/288

Comment by Dr. Krishna Kumari Challa on July 16, 2016 at 8:16am

Bright light accelerates ageing in mice

Exposure to artificial light weakens rodent’ muscles and bones, but risks to humans are not clear 

Lucassen and Johanna Meijer, a neuroscientist at Leiden, report  in Current Biology that a constant barrage of bright light prematurely ages mice, playing havoc with their circadian clocksand causing a cascade of health problems.

Mice exposed to constant light experienced bone-density loss, skeletal-muscle weakness and inflammation; restoring their health was as simple as turning the lights off. The findings are preliminary, but they suggest that people living in cities flooded with artificial light may face similar health risks.

Many previous studies have hinted at a connection between artificial light exposure and health problems in animals and people. Epidemiological analyses have found that shift workers have an increased risk of breast cancer, metabolic syndrom and osteoporosis. People exposed to bright light at night are more likely to have cardiovascular disease and often don’t get enough sleep.

And disruption of the biological clock alone might not cause the health effects reported in the study, says Steven Lockley, a neuroscientist at Harvard Medical School in Boston, Massachusetts. Poor sleep and light itself can each affect health, so an altered circadian clock may not be to blame.

The study should be a warning to people who work in intensive-care facilities or long-term care facilities, and to shift workers.

http://www.nature.com/news/bright-light-accelerates-ageing-in-mice-...

Comment by Dr. Krishna Kumari Challa on July 16, 2016 at 7:27am

Mice Watching "Touch of Evil" Teach Scientists About the Mind's Eye

By tracking mice neurons, scientists hope to understand consciousness

Comment by Dr. Krishna Kumari Challa on July 14, 2016 at 6:07am

Astronomers find a freak Frankenstein galaxy made of parts of other galaxies
The unassuming galaxy turns out to have a lot of parts taken from galaxies that came before.
About 250 million light-years away, there's a neighborhood of our universe that astronomers had considered quiet and unremarkable. But now, scientists have uncovered an enormous, bizarre galaxy possibly formed from the parts of other galaxies.

A new study to be published in the Astrophysical Journal reveals the secret of UGC 1382, a galaxy that had originally been thought to be old, small and typical. Instead, scientists using data from NASA telescopes and other observatories have discovered that the galaxy is 10 times bigger than previously thought and, unlike most galaxies, its insides are younger than its outsides, almost as if it had been built using spare parts.
"This rare, 'Frankenstein' galaxy formed and is able to survive because it lies in a quiet little suburban neighborhood of the universe, where none of the hubbub of the more crowded parts can bother it," said study co-author Mark Seibert of the Observatories of the Carnegie Institution for Science, Pasadena, California. "It is so delicate that a slight nudge from a neighbor would cause it to disintegrate."
As it turns out, UGC 1382, at about 718,000 light-years across, is more than seven times wider than the Milky Way. It is also one of the three largest isolated disk galaxies ever discovered, according to the study. This galaxy is a rotating disk of low-density gas. Stars don't form here very quickly because the gas is so spread out.

But the biggest surprise was how the relative ages of the galaxy's components appear backwards. In most galaxies, the innermost portion forms first and contains the oldest stars. As the galaxy grows, its outer, newer regions have the youngest stars. Not so with UGC 1382. By combining observations from many different telescopes, astronomers were able to piece together the historical record of when stars formed in this galaxy -- and the result was bizarre.

"The center of UGC 1382 is actually younger than the spiral disk surrounding it," Seibert said. "It's old on the outside and young on the inside. This is like finding a tree whose inner growth rings are younger than the outer rings."

The unique galactic structure may have resulted from separate entities coming together, rather than a single entity that grew outward. In other words, two parts of the galaxy seem to have evolved independently before merging -- each with its own history.
More galaxies like this may exist, but more research is needed to look for them.

"By understanding this galaxy, we can get clues to how galaxies form on a larger scale, and uncover more galactic neighborhood surprises".
- Astronomy.com

Comment by Dr. Krishna Kumari Challa on July 14, 2016 at 6:01am

Improving climate predictions with the help of cluster satellites
A team of small, shoebox-sized satellites, flying in formation around the Earth, could estimate the planet’s reflected energy with twice the accuracy of traditional monolith satellites, according to an MIT-led study published online in Acta Astronautica. If done right, such satellite swarms could also be cheaper to build, launch, and maintain.

The researchers, led by Sreeja Nag, a former graduate student in MIT’s Department of Aeronautics and Astronautics (AeroAstro), simulated the performance of a single large, orbiting satellite with nine sensors, compared with a cluster of three to eight small, single-sensor satellites flying together around the Earth. In particular, the team looked at how each satellite formation measures albedo, or the amount of light reflected from the Earth — an indication of how much heat the planet reflects.
The team found that clusters of four or more small satellites were able to look at a single location on Earth from multiple angles, and measure that location’s total reflectance with an error that is half that of single satellites in operation today. Nag says such a correction in estimation error could significantly improve scientists’ climate projections.
“Total outgoing radiation is actually one of the biggest uncertainties in climate change, because it is a complex function of where on Earth you are, what season it is, what time of day it is, and it’s very difficult to ascertain how much heat leaves the Earth,” Nag says. “If we can estimate the reflectance of different surface types, globally, frequently, and more accurately, which a cluster of satellites would let you do, then at least you’ve solved one part of the climate puzzle.”
“The Earth does not reflect equally in all directions,” Nag says. “If you don’t get these multiple angles, you might under- or overestimate how much it’s reflecting, if you have to extrapolate from just one direction.”

Today, satellites that measure the Earth’s albedo typically do so with multiple cameras, arranged on a single satellite. For example, NASA’s Multi-angle Imaging SpectroRadiometer (MISR) instrument on the Terra satellite houses nine cameras that take images of the Earth from a fan-like arrangement of angles. Nag says the drawback of this design is that the cameras have a limited view, as they are not designed to change angles and can only observe within a single plane.

Instead, the team proposes a cluster of small satellites that travel around the Earth in a loose formation, close enough to each other to be able to image the same spot on the ground from their various vantage points. Each satellite can move within the formation, taking pictures of the same spot at the same time from different angles.

“Over time, the cluster would cover the whole Earth, and you’d have a multiangular, 3-D view of the entire planet from space, which has not been done before with multiple satellites,” Nag says. “Moreover, we can use multiple clusters for more frequent coverage of the Earth.”
http://www.sciencedirect.com/science/article/pii/S0094576516303149

Comment by Dr. Krishna Kumari Challa on July 12, 2016 at 9:53am

Malaria teamwork makes it more dangerous to humans
Getting infected by two malaria species can improve conditions for the second species, making the disease more dangerous and persistent than lone infections, a mouse study shows.

According to a paper made public on 5 July, being infected with both Plasmodium falciparum and Plasmodium vivax can provide this second parasite species with more of the resources it needs to prosper.

This is because P. falciparum attacks red blood cells of all ages but when the blood regenerates it offers more subsistence for P. vivax, which prefers to attack young red blood cells, the researchers say.

'The findings challenge ideas that one species will outcompete the other', says coauthor Sarah Reece, a biologist at the University of Edinburgh in the United Kingdom. “This explains why infections involving two parasite species can pose a greater health risk to patients.”

Humans are a bit more complicated than mice, because the nature of the immune response actually leads over time to protection from disease severity.

In their paper, the authors admit it will be hard to translate their research into applicable knowledge for human treatment. They write that previous infections and the ability of P. vivax to remain in the body at a dormant stage can complicate the picture of coinfections. 

http://onlinelibrary.wiley.com/doi/10.1111/ele.12639/abstract;jsess...

Comment by Dr. Krishna Kumari Challa on July 9, 2016 at 5:52am

Big Bang or Big Bounce?

Perfect Quantum Cosmological Bounce

A new study of the early universe reveals how it could have been formed from an older collapsing universe, rather than being brand new.

The universe is currently expanding and it is a common theory that this is the result of the 'Big Bang' - the universe bursting into existence from a point of infinitely dense and hot material.

However, physicists have long debated this idea as it means the universe began in a state of complete breakdown of physics as we know it. Instead, some have suggested that the universe has alternated between periods of expansion and contraction, and the current expansion is just one phase of this.

This so-called 'Big Bounce' idea has been around since 1922, but has been held back by an inability to explain how the universe transitions from a contracting to an expanding state, and vice versa, without leading to an infinite point.

Now, in a new study published today in Physical Review Letters, Dr Steffen Gielen from Imperial College London and Dr Neil Turok, Director of the Perimeter Institute for Theoretical Physics in Canada, have shown how the Big Bounce might be possible.

Cosmological observations suggest that during its very early life, the universe may have looked the same at all scales - meaning that the physical laws that that worked for the whole structure of the universe also worked at the scale of the very small, smaller than individual atoms. This phenomenon is known as conformal symmetry.

In today's universe, this is not the case - particles smaller than atoms behave very differently to larger matter and the symmetry is broken. Subatomic particle behaviour is governed by what is called quantum mechanics, which produces different rules of physics for the very small.

For example, without quantum mechanics, atoms would not exist. The electrons, as they whizz around the nucleus, would lose energy and collapse into the centre, destroying the atom. However, quantum mechanics prevents this from happening.

In the early universe, as everything was incredibly small, it may have been governed solely by the principles of quantum mechanics, rather than the large-scale physics we also see today.

In the new study, the researchers suggest that the effects of quantum mechanics could prevent the universe from collapsing and destroying itself at end of a period of contraction, known as the Big Crunch. Instead, the universe would transition from a contracting state to an expanding one without collapsing completely.

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.117.021301

Comment by Dr. Krishna Kumari Challa on July 9, 2016 at 5:38am

Viral hepatitis kills as many as malaria, TB or HIV/AIDS, finds study
Viral hepatitis has become one of the leading causes of death and disability across the globe – killing at least as many people annually as TB, malaria or HIV/AIDS. This is the finding of new research from scientists at Imperial College London and University of Washington, who analysed data from 183 countries collected between 1990 and 2013.


Viral hepatitis exists in five forms – A, B, C, D and E and is transmitted through bodily fluids, or, in the case of A and E, through food or drink contaminated with faeces.

A majority of the deaths – 96 per cent - were due to hepatitis B and C which cause liver damage (cirrhosis), and liver cancer. Symptoms include fatigue, jaundice and nausea, however in many people the infection is symptomless - and so an individual may not know they are infected until they develop serious complications.

The researchers, who published their findings in journal The Lancet, found that viral hepatitis deaths increased by 63 per cent over the 23-year period. The study, which was co-led by scientists at the Institute for Health Metrics and Evaluation at the University of Washington, found deaths from viral hepatitis were higher in high and middle-income countries than lower income countries. The authors say the overall disease burden is now more evenly divided between higher and lower income nations.
The team say we now urgently need international measures to address this crisis.
Although there are effective treatments and vaccines for viral hepatitis, there is very little money invested in getting these to patients –especially compared to malaria, HIV/AIDS and TB. We now have a viral hepatitis global action plan approved in May by the World Health Assembly, and we now need to implement it.
The researchers found deaths from acute infection, cirrhosis and liver disease caused by viral hepatitis had increased by 63 per cent from 890,000 in 1990 to 1.45 million in 2013.

By comparison, in 2013, 1.3 million people worldwide died from AIDS, 1.4 million from TB, and 855,000 from malaria, according to a 2015 study by the Institute for Health Metrics and Evaluation.
In the current study, most hepatitis deaths were found to occur in East Asia, and the majority of global deaths were due to hepatitis B and C. One potential reason for the high number of deaths from hepatitis B and C is these strains cause long-term infections with very few immediate symptoms. They can therefore progress silently until they trigger serious liver damage or cancer. Although we have had an effective hepatitis B vaccine for some years, there is still a large proportion of the world which is unvaccinated. We have no similar vaccine for hepatitis C.

Source: Imperial College London

Comment by Dr. Krishna Kumari Challa on July 5, 2016 at 7:10am

Soy diesel found to be less toxic than other fuels
Unlike conventional diesel, fuel made from soybeans does not directly damage lung cells, a lab study has shown.

“Some of the soybean biodiesel presently being used in Brazil does not exhibit direct adverse effects on human lung cells nor [does it] induce inflammatory response,” says the paper, published in the August issue of the journal Toxicology in Vitro.

To assess the fuels’ toxic effects, researchers from Brazil and Puerto Rico exposed lung cell cultures to particles emitted by the combustion of four types of fuel: commercial diesel from fossil fuel sources, pure soy-based biodiesel, soy-based biodiesel with additives and ethanol with additives.

After exposure, the scientists counted the proportion of cells that survived to assess the fuels’ toxicity, and measured the quantity of cytokines the cells produced. Cytokines are proteins secreted by certain cells, including lung cells, involved in the regulation of inflammatory processes. An increase in their production can cause damage to the cells.

Adriana Gioda, a chemist at the Pontifical Catholic University of Rio de Janeiro in Brazil and co-author of the paper, says this study is the first demonstration that soy-based biodiesel does not cause a significant toxic reaction in lung cells.

However, the authors warn that these results should not be “considered as an absolute positive outcome” and should pave the way for further studies in live animals.
 

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