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Galaxy

Strange exoplanet orbiting small cool star challenges planetary formation theories

© ANU
Artist's impression of HATS-6
The Australian discovery of a strange exoplanet orbiting a small cool star 500 light years away is challenging ideas about how planets form.

"We have found a small star, with a giant planet the size of Jupiter, orbiting very closely," said researcher George Zhou from the Research School of Astrophysics and Astronomy.

"It must have formed further out and migrated in, but our theories can't explain how this happened."

In the past two decades more than 1,800 extrasolar planets (or exoplanets) have been discovered outside our solar system orbiting around other stars.

The host star of the latest exoplanet, HATS-6, is classed as an M-dwarf, which is one of the most numerous types of stars in galaxy. Although they are common, M-dwarf stars are not well understood. Because they are cool they are also dim, making them difficult to study.

Info

Researchers have found a way to modify blood types

© Thinkstock
There's a serious supply-and-demand problem when it comes to blood transfusions: Patients are in constant need of the bodily fluid, which delivers oxygen and nutrients to the cells, but because they need a specific type, hospitals and blood banks often experience shortages.

Fortunately, chemists from the University of British Columbia and colleagues from the Center for Blood Research have created an enzyme that could potentially solve this problem by cutting off the antigens (sugars) found in Type A and Type B blood to make it more like Type O, which is universal and can be given to patients regardless of their blood types.

UBC postdoctoral fellow David Kwan, lead author of a new Journal of the American Chemical Society study detailing the research, explained in a statement that their "mutant enzyme" is "very efficient" at cutting off antigens in A and B blood, and "much more proficient" at removing the A-antigen subtypes that the parent enzymes tend to struggle with.

Info

Left-handed people have same genetic code abnormality as those with situs inversus

© The Independent, UK
100,000 people had their genes sequenced to determine handedness.
Left-handed people may be even more unique than first thought, thanks to a study that has linked one rare condition with another.

100,000 people had their genes sequenced to determine handedness, and it seems that a condition called situs inversus may be able to provide clues behind what makes people use their left hand instead of the right.

One in 20,000 people are affected by the condition which mirrors the major organs from their major positions: for instance the heart would be on the right side of the body instead of the left.

Human geneticist Silvia Paracchini and her team from the University of St Andrews found that the part of the genetic code which is abnormal in people who have situs inversus is the same that affects handedness.

Paracchini said: "The reason why it fascinates us is that we don't really understand it. It's fascinating but also puzzling.

"There must be an evolutionary advantage [to being right-handed]."

While 25 per cent of all left handedness can be linked by a person's genes, the other 75 per cent is still yet to be fully explained.

Comment: Apparently claims are being made in the above article that have no documentation at all: See: Handedness and Military Leaders
When one looks at the evidence for individual claims though (rather than just taking the word of numerous websites for granted), the issue immediately clouds still further. For example, the case for Alexander the Great being left-handed is tenuous at best. His constant inclusion at the top of lists of left-handers is a relatively recent phenomenon, apparently arising from a misreading of accounts in the 1960s and thereafter, and possibly arising from his own (entirely unsubstantiated) claim to have conquered a country of left-handed people. In fact, Alexander is always shown in classical depictions as right-handed, and none of the contemporary or near-contemporary historians, who documented his life so meticulously, make any mention of an unusual trait like left-handedness.

The notable Egyptian Pharaoh Ramses II is usually numbered among the host of left-handers, presumably on the strength of the tomb inscription in which he claims "with my left hand I hurled the dart", totally ignoring the next line which reads "with my right I swung the blade". Incidentally, neither does this make him ambidextrous (what is a man wielding two weapons to do?)

It is not at all clear why Julius Caesar should be considered a left-hander, as he usually is. There does not appear to be any documentary evidence to suggest it, and to assert that he encouraged the Roman practice of shaking the right hand in greeting because he was left-handed (and therefore, presumably, unscrupulous) is circular reasoning of the highest order. The common inclusion of the Roman Emperor Commodus in such lists is even more puzzling. Although almost definitely a left-hander, and a fierce and merciless fighter, Commodus was one of Rome's worst Emperors and a poor military leader. Interestingly, Emperor Tiberius was also a left-hander according to biographer Suetonius, and a much better military leader, but he is hardly ever mentioned in the lists. All this merely demonstrates the tendency for websites and blogs to copy each other unthinkingly.



Beaker

Bad reputation of viruses not universally deserved

"The word, virus, connotes morbidity and mortality, but that bad reputation is not universally deserved," said Marilyn Roossinck, PhD, Professor of Plant Pathology and Environmental Microbiology and Biology at the Pennsylvania State University, University Park. "Viruses, like bacteria, can be important beneficial microbes in human health and in agriculture," she said. Her review of the current literature on beneficial viruses appeared ahead of print April 24 in the Journal of Virology, which is published by the American Society for Microbiology.

In sharp contrast to the gastrointestinal distress it causes in humans, the murine (mouse infecting) norovirus plays a role in development of the mouse intestine and its immune system, and can actually replace the beneficial effects of certain gut bacteria when these have been decimated by antibiotics. Normal, healthy gut bacteria help prevent infection by bacteria that cause gastrointestinal illness, but excessive antibiotic intake can kill the normal gut flora, and make one vulnerable to gastrointestinal disease. However, norovirus infection of mice actually restored the normal function of the immune system's lymphocytes and the normal morphology of the intestine, said Roossinck.

Mammalian viruses can also provide immunity against bacterial pathogens. Gamma-herpesviruses boost mice resistance to Listeria monocytogenes, an important human gastrointestinal pathogen, and to Yersinia pestis, otherwise known as plague. "Humans are often infected with their own gamma-herpes viruses, and it is conceivable that these could provide similar benefits," said Roossinck.

Latent herpesviruses also arm natural killer cells, an important component of the immune system, which kill both mammalian tumor cells, and cells that are infected with pathogenic viruses.

Comment: For more information on some beneficial effects of viruses, see:


Bug

A lesson from nature? Bumblebees use nicotine to combat parasites

Image
© D Baracchi/QMUL
This is a bumblebee feeding at an artificial feeder.

Bumblebees that have been infected by parasites seek out flowers with nicotine in the nectar, likely to fight off the infection, new research has found. The nicotine appears to slow the progression of disease in infected bees but has harmful effects when consumed by healthy bees.

Researchers from Queen Mary University of London (QMUL) and Royal Holloway, University of London (RHUL), gave bumblebees the option to choose between a sugar solution with nicotine in it and one without. Those bees infected with the Crithidia bombi parasite were more likely to go for the nicotine-laced nectar than those that weren't infected.

Infected bumblebees that consumed nicotine delayed the progress of the infection for a few days, showing lower levels of parasites than those that had not. However, it did not increase the life expectancy of those bees, meaning that the direct benefits of nicotine for the bee colony remain to be identified.

Galaxy

Mysterious X-rays could mark stellar graveyard

© NASA
Astronomers are baffled by the discovery of a mysterious fog of high energy X-rays blasting out of the centre of our galaxy.

The discovery, reported in the journal Nature, challenges our understanding of the physics taking place in the galactic centre.

The astronomers speculate the mysterious cloud could be generated by a vast graveyard of thousands of stellar remnants clustered in the shadow of the supermassive black hole.

But the source still eludes them.

"This is something that has never been seen before, I only wish we knew what it is that we discovered," says one of the study's authors Professor Chuck Hailey of the University of Columbia in New York.

"We have quite a few theories of what it could be, but none of them fits the facts, so at this point it's something of a mystery."

The international team of scientists discovered the huge X-ray cloud during observations using the NuSTAR X-ray Observatory to study a region 30 light-years wide around the supermassive black hole at the centre of the Milky Way galaxy.

"There really was no evidence to suggest that there should be this diffused foggy type of high energy X-rays in the region around the central black hole," says Hailey.

Nuke

Chernobyl forests aren't decaying properly - significant risk of fires further spreading radiation

© T.A.Mousseau & A.P. Møller
Fallen trees in Chernobyl's infamous red forest.
It wasn't just people, animals and trees that were affected by radiation exposure at Chernobyl, but also the decomposers: insects, microbes, and fungi

Nearly 30 years have passed since the Chernobyl plant exploded and caused an unprecedented nuclear disaster. The effects of that catastrophe, however, are still felt today. Although no people live in the extensive exclusion zones around the epicenter, animals and plants still show signs of radiation poisoning.

Birds around Chernobyl have significantly smaller brains that those living in non-radiation poisoned areas; trees there grow slower; and fewer spiders and insects - including bees, butterflies and grasshoppers - live there. Additionally, game animals such as wild boar caught outside of the exclusion zone - including some bagged as far away as Germany - continue to show abnormal and dangerous levels of radiation.

However, there are even more fundamental issues going on in the environment. According to a new study published in Oecologia, decomposers - organisms such as microbes, fungi and some types of insects that drive the process of decay - have also suffered from the contamination. These creatures are responsible for an essential component of any ecosystem: recycling organic matter back into the soil. Issues with such a basic-level process, the authors of the study think, could have compounding effects for the entire ecosystem.

The team decided to investigate this question in part because of a peculiar field observation. "We have conducted research in Chernobyl since 1991 and have noticed a significant accumulation of litter over time," the write. Moreover, trees in the infamous Red Forest - an area where all of the pine trees turned a reddish color and then died shortly after the accident - did not seem to be decaying, even 15 to 20 years after the meltdown.

Comment: April 29, 2015: It is burning right now.

Chernobyl forest fires may result in large scale re-release of radiation
Forest fires heading for Chernobyl nuclear plant - Ukraine Interior Ministry

Edit: Chernobyl NPP wildfire fully put out — Ukraine's Emergencies State Service


Info

Scientists find evidence of large hydrologic network under Antarctica's 'bleeding glacier'

© Peter Rejcek, National Science Foundation
Antarctica's Bleeding Glacier
Antarctica's Dry Valleys are the most arid places on Earth, but underneath their icy soils lies a vast and ancient network of salty, liquid water filled with life, a new study finds.

The Dry Valleys are almost entirely ice-free, except for a few isolated glaciers. The only surface water is a handful of small lakes. Inside the canyons, the climate is extremely dry, cold and windy; researchers have stumbled upon mummified seals in these gorges that are thousands of years old.

Yet there is life in this extreme landscape. For instance, bacteria living under Taylor Glacier stain its snout a deep blood red. The rust-colored brine, called Blood Falls, pours into Lake Bonney in the southernmost of the three largest Dry Valleys. The dramatic colors offer shocking relief to senses overwhelmed by the glaring white ice and dull brown rocks.

Now, for the first time, scientists have traced the water underneath Taylor Glacier to learn more about the mysterious Blood Falls. In the process, the researchers discovered that briny water underlies much of Taylor Valley. The subsurface network connects the valley's scattered lakes, revealing that they're not as isolated as scientists once thought. The findings were published today (April 28) in the journal Nature Communications.

Satellite

Astonishing images of Mercury captured by NASA's Messenger probe before it smashes into planet

Image
© Reuters / NASA / Johns Hopkins University Applied Physics Laboratory / Carnegie Institution of Washington / Handout
As Judgment Day approaches for NASA's Messenger probe, stunning new pictures have emerged of the planet it is set to crash into on Thursday: Mercury.

The incredible close-up shots show our solar system's smallest planet as never before.

The psychedelic appearance is explained by NASA overlaying the pictures from the spacecraft's Visual and Infrared Spectrometer (Virs) onto a black and white mosaic in order to accentuate features such as craters and volcanic vents.

Robot

Gecko-inspired robots can lift items 100 times their weight

Image
© Screenshot from youtube.com video
Tiny robots can climb kilometers of walls carrying objects over 100 times their own weight. They are to be presented by their creators, Stanford engineers at an international conference to take place in the US next month.

The secret of a series of the super-strong robots, created by mechanical engineers at Stanford University in California, is in their feet, the design of which was inspired by geckos - or rather their well-known climbing skills, New Scientist reported.