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Comment by Dr. Krishna Kumari Challa on May 7, 2014 at 9:24am

Each time a human cell divides, it must first make a copy of its 46 chromosomes to serve as an instruction manual for the new cell. Normally, this process goes off without a hitch. But from time to time, the information isn't copied and collated properly, leaving gaps or breaks that the cell has to carefully combine back together. Researchers have long recognized that some regions of the chromosome,called "fragile sites," are more prone to breakage and can be a breeding ground for human cancers. But they have struggled to understand why these weak spots in the genetic code occur in the first place.

A comprehensive mapping of the fragile sites in yeast by a team of Duke researchers shows that fragile sites appear in specific areas of the genome where the DNA-copying machinery is slowed or stalled, either by certain sequences of DNA or by structural elements. The study, which appears May 5 in Proceedings of the National Academy of Sciences, could give insight into the origins of many of the genetic abnormalities seen in solid tumors.
In this study, researchers wanted to find the link between the copier malfunction and its genetic consequences on a genome-wide scale. First, he knocked down the levels of DNA polymerase in yeast cells to ten-fold lower than normal. Then he used microarray or "gene chip" technology to map where segments of DNA had been rearranged, indicating that a fragile site had once been there.

After finding those fragile sites, his laboratory spent more than a year combing through the literature for any recurring themes among the genomic regions they had uncovered. Eventually they showed that the fragile sites were associated with sequences or structures that stalled DNA replication, esoteric entities such as inverted repeats, replication termination signals, and transfer RNA genes.
In addition these fragile sites created a surprisingly unstable genome, resulting in a chaotic milieu of rearrangements, duplications and deletions of pieces of DNA or even the gain or loss of entire chromosomes.
"It has been known for a long time that many cancer cells have an abnormal number of chromosomes, and many different chromosome rearrangements have been observed in various tumor cells. It is likely that there are many different causes of chromosome instability in cancer cells. The current work suggests that those chromosomal rearrangements observed at fragile sites and found in solid tumors may be due to breaks from perturbed replication."

-http://duke.edu/

Comment by Dr. Krishna Kumari Challa on May 7, 2014 at 9:19am

Are we ready for contact with extraterrestrial intelligence?
The SETI project scientists are known for tracking possible extraterrestrial signals, but now they are also considering sending messages from Earth telling of our position. A researcher from the University of Cádiz (Spain) questions this idea in view of the results from a survey taken by students, revealing the general level of ignorance about the cosmos and the influence of religion when tackling these matters. The Search for ExtraTerrestrial Intelligence (SETI) project is an initiative that began in the 70s with funding from NASA, but that has evolved towards the collaboration of millions of Internet users for the processing of data from the Arecibo Observatory (Puerto Rico), where space tracking is carried out.

Now the members of this controversial project are trying to go further and not only search for extraterrestrial signs, but also actively send messages from Earth (Active SETI) to detect possible extraterrestrial civilisations.. Astrophysicists, such as Stephen Hawking, have already warned of the risk that this implies for humanity, since it could favour the arrival of beings with more advanced technology and dubious intentions.
The ethical and sociological implications of this proposal have been analysed by the neuro-psychologist Gabriel G. de la Torre, professor at the University of Cádiz and participant in previous projects such as Mars 500 or space psychology topical team project financed by the European Space Agency, who wonders: "Can such a decision be taken on behalf of the whole planet? What would happen if it was successful and 'someone' received our signal? Are we prepared for this type of contact?"
The results, published in the journal 'Acta Astronautica', indicate that, as a species, humanity is still not ready for trying to actively contact a supposed extraterrestrial civilisation, since people lack knowledge and preparation. For this reason, SETI researchers are recommended in this study to look for alternative strategies.

"This pilot study demonstrates that the knowledge of the general public of a certain education level about the cosmos and our place within it is still poor. Therefore, a cosmic awareness must be further promoted -- where our mind is increasingly conscious of the global reality that surrounds us -- using the best tool available to us: education," De la Torre emphasised. "In this respect, we need a new Galileo to lead this journey."

It was deduced from the questionnaires, which will soon be available to everyone on line, that university students and the rest of society lack awareness on many astronomical aspects, despite the enormous progress of science and technology. It also revealed that the majority of people consider these subjects according to their religious belief and that they would rely on politicians in the event of a huge global-scale crisis having to be resolved.

"Regarding our relation with a possible intelligent extraterrestrial life, we should not rely on moral reference points of thought, since they are heavily influenced by religion. Why should some more intelligent beings be 'good'?," added the researcher, who believes that this matter should not be monopolized by a handful of scientists: "In fact, it is a global matter with a strong ethical component in which we must all participate."
http://esciencenews.com/articles/2014/05/06/are.we.ready.contact.wi...

Comment by Dr. Krishna Kumari Challa on May 7, 2014 at 7:13am

Comment by Dr. Krishna Kumari Challa on May 6, 2014 at 8:57am

Making sense of at which direction and at what speed a car is moving may not be possible without the interpretation of the brain, but processing of some of these information starts right at the retinas of the eyes.

Researchers have now explained how the various types of cells in the retina are wired to help the eyes detect the direction and speed of moving objects.

"The wiring diagram represents only a tiny proportion of the total number of connections on the retina," said Sebastian Seung, a computational neuro scientist at Massachusetts Institute of Technology in the US.

To understand how cells are wired together in the retina, the researchers analysed high-resolution electron microscope images of a mouse retina with the help of nearly 2,200 members of EyeWire, an online 'citizen-science' game set up to help with brain-mapping efforts.
To understand how cells are wired together in the retina, the researchers analysed high-resolution electron microscope images of a mouse retina with the help of nearly 2,200 members of EyeWire, an online 'citizen-science' game set up to help with brain-mapping efforts.

Players traced the pathways through the layers of cells to create a high-resolution wiring diagram of part of the retina.

The reconstructed map showed that while one type of bipolar cell (that transmit signals from the photoreceptors to the ganglion cells) connects to the amacrine cells (responsible for 70 percent of input to retinal ganglion cells) filaments close to the cell body, another does do so farther away along the length of the filaments.

The bipolar cells that connect closer to the starburst amacrine cell bodies are known to relay their messages with a time delay, whereas the others transmit their immediately, the researchers discovered.

Because of the lag in the first type of connection, signals that hit two nearby locations on the retina at two slightly different times - as would happen when an object moves across the visual field - could reach the same amacrine-cell filament at the same time.

According to the researchers, the following could help explain how the retina detects motion: The amacrine cell might fire only when it receives this combined information, signalling that something is moving in the direction of the filament.

Stimuli not moving in the direction of the filament would produce impulses that reach the amacrine cell at different times, so that it would not fire.

The study appeared in the journal Nature.

Comment by Dr. Krishna Kumari Challa on May 6, 2014 at 8:36am

How volcanoes erupt: Using friction experiments, University of Liverpool scientists have shown that frictional melting plays a role in determining how a volcano will erupt.
Volcanologists from the University of Liverpool have discovered how lava dome volcanoes erupt. This could help develop methods on predicting how volcanoes will act.

The process of frictional melting determines how the volcano will erupt. The speed of the lava rise and how much friction it creates is determined by this process. Within the lava dome the magma and rocks melt as they rub together by the intense heat. This creates a method called ‘stick-slip’ when the magma adheres to the rocks and stops moving upward until pressure builds — when enough pressure builds up, the magma moves upward again. This process continues until the magma reaches the mouth of the volcano in an eruption.

By studying the stick-slip process, a research team, led by University of Liverpool volcanologist Dr. Jackie Kebdrick, has conducted experiments that could help predict eruptions.

The researchers analyzed lava collected from Mount St. Helens in the United States and the Soufriere Hills volcano in Montserrat. Remnants of pseudotachylyte, which is a cooled friction melt, were found. The study also revealed the process takes place in the conduit leading to the top of the volcano before its eruption.

“The closer we get to understanding the way magma behaves, the closer we will get to the ultimate goal: predicting volcanic activity when unrest begins. Whilst we can reasonably predict when a volcanic eruption is about to happen, this new knowledge will help us to predict how the eruption will behave. With a rapidly growing population inhabiting the flanks of active volcanoes, understanding the behaviour of lava domes becomes an increasing challenge for volcanologists.
http://www.redorbit.com/news/science/1113137915/volcanic-eruption-p...

Comment by Dr. Krishna Kumari Challa on May 6, 2014 at 7:05am

Some e-cigarettes deliver a puff of carcinogens
Electronic cigarettes appear to be safer than ordinary cigarettes for one simple — and simply obvious — reason: People don't light up and smoke them.

With the e-cigarettes, there is no burning tobacco to produce myriad new chemicals, including some 60 carcinogens.

But new research suggests that, even without a match, some popular e-cigarettes get so hot that they, too, can produce a handful of the carcinogens found in cigarettes and at similar levels.

A study to be published this month in the journal Nicotine and Tobacco Research found that the high-power e-cigarettes known as tank systems produce formaldehyde, a known carcinogen, along with the nicotine-laced vapour that their users inhale. The toxin is formed when liquid nicotine and other e-cigarette ingredients are subjected to high temperatures, according to the study. A second study that is being prepared for submission to the same journal points to similar findings.

The long-term effects of inhaling nicotine vapour are unclear, but there is no evidence to date that it causes cancer or heart disease as cigarette smoking does. Indeed, many researchers agree that e-cigarettes will turn out to be much safer than conventional cigarettes, an idea that e-cigarette companies have made much of in their advertising. The website for Janty, a company that manufactures popular tank systems, says the benefits of e-cigarettes include having "no toxins associated with tobacco smoking."

Nonetheless, the new research suggests how potential health risks are emerging as the multibillion-dollar e-cigarette business rapidly evolves, and how regulators are already struggling to keep pace. While the Food and Drug Administration last month proposed sweeping new rules that for the first time would extend its authority to e-cigarettes, the FDA has focused largely on what goes into these products — currently, an unregulated brew of chemicals and flavourings — rather than on what comes out of them, as wispy plumes of flavoured vapour.
This finding suggests that in certain conditions," e-cigarettes "might expose their users to the same or even higher levels of carcinogenic formaldehyde as tobacco smoke.

Comment by Dr. Krishna Kumari Challa on May 6, 2014 at 6:50am

Odors define us, yet the scientific zeitgeist is that we don’t communicate through pheromones—scents that influence behavior. A new study challenges that thinking, finding that scent can change whether we think someone is masculine or feminine.

Humans carry more secretion and sweat glands in their skin than any other primate. Yet 70% of people lack a vomeronasal organ, a crescent-shaped bundle of neurons at the base of each nostril that allows a variety of species—from reptiles to nonprimate mammals—to pick up on pheromones. (If you’ve ever seen your cat huff something, he’s using this organ.) Still, scientists have continued to hunt for examples of pheromones that humans might sense.

Two strong candidates are androstadienone (andro) and estratetraenol (estra). Men secrete andro in their sweat and semen, while estra is primarily found in female urine. Researchers have found hints that both trigger arousal—by improving moods and switching on the brain’s “urge” center, the hypothalamus—in the opposite sex. Yet to be true pheromones, these chemicals must shape how people view different genders.

That’s exactly what they do, researchers from the Chinese Academy of Sciences in Beijing report online today in Current Biology.
http://bcove.me/qupsica9
http://news.sciencemag.org/biology/2014/05/man-or-woman-trust-your-...

Comment by Dr. Krishna Kumari Challa on May 6, 2014 at 6:46am

Put science before emotion over radioactive waste
http://bismarcktribune.com/news/columnists/put-science-before-emoti...

Comment by Dr. Krishna Kumari Challa on May 6, 2014 at 6:43am

Comment by Dr. Krishna Kumari Challa on May 6, 2014 at 6:40am

Young blood may reverse ageing : Researchers think it may contain natural chemicals that turn back the clock to rejuvenate the ageing brain
Scientists have shown that an infusion of young blood can reverse signs of ageing. Although the experiment was conducted on laboratory mice, the next step could involve a study of elderly humans.
In the study, blood from three-month-old mice was repeatedly injected into 18-month-old mice near the end of their natural life span. The "vampire therapy" improved the performance of the elderly mice in memory and learning tasks. Structural, molecular and functional changes were also seen in their brains.

Writing in the journal Nature Medicine, the US team led by Dr Tony Wyss-Coray, from Stanford University, said: "Our data indicate that exposure of aged mice to young blood late in life is capable of rejuvenating synaptic plasticity and improving cognitive function.

"Future studies are warranted in aged humans and potentially those suffering from age-related neurodegenerative disorders."
Evidence was seen of new connections forming in the hippocampus, a brain region vital to memory and sensitive to ageing.

Ageing mice given eight infusions of young blood over three weeks improved their performance in mental tests. Infusions of blood from other elderly mice had no effect.

What caused the changes is still unknown, but it appears to involve activation of a protein called Creb in the hippocampus that helps regulate certain genes.

The scientists wrote: "One possibility is that introducing 'pro-youthful' factors from aged blood can reverse age-related impairments in the brain, and a second possibility is that abrogating pro-ageing factors from aged blood can counteract such impairments.These two possibilities are not mutually exclusive, warrant further investigation, and may each provide a successful strategy to combat the effects of ageing."

Dr Eric Karran, from the dementia charity Alzheimer's Research UK, described the results as "interesting", but added that the study "does not investigate the type of cognitive impairment that is seen in Alzheimer's disease".

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