Jan 16, 2016
Found on the east wall of the Cathedral of the Transfiguration of the Savior in Pereslavl-Zalessky, some 60 miles from Moscow, the inscription names 20 conspirators and briefly describes what happened on the night of June 29, 1174, when Prince Bogolyubsky was stabbed to death in his bedchamber.
“We suppose the inscription was some sort of official announcement about the murder of Prince Andrey and the condemnation of the murderers,” Alexey Gippius, professor at the National Research University Higher School of Economics and correspondent member of the Russian Academy of Sciences, told Discovery News.
“The number of the names confirms information given by the chronicles, where however only three names are mentioned,” he added.
Andrey I Yuryevich, commonly known as Andrey Bogolyubsky (“Andrew the God-Loving”), was a grandson of Vladimir Monomakh, the Grand Prince of Kiev from 1113 to 1125.
As the prince of Rostov-Suzdal and grand prince of Vladimir, he strengthened the importance of the northeastern Russian lands which he tried to unite under his authority.
He moved the political hub from Kiev to the city-state of Vladimir, making it a powerful center of religious and civil life. Seeing their power strongly reduced, the boyars, or upper nobility, plotted against the autocratic prince.
Twenty conspirators burst into Andrey’s chamber and killed him.
“The murder of the prince is one of the most dramatic and mysterious events of the second half of the 12th century,” Nikolai Makarov, director of the Institute of Archaeology of the Russian Academy of Sciences, said in a statement.
He noted the assassination was a consequence of conflicts among the political elite of the Vladimir-Suzdal land, turned by Andrey into one of the dominant political centers of Russia.
“However, the details of these conflicts, which are often interpreted as a clash of princely power and nobility, are unknown to us,” Makarov said.
Located in the middle of the southern apse of the cathedral, the inscription consists of two columns and is crowned by a cross.
Read more at Discovery News
According to the study, the Iceman’s maternal line appears to have originated and died out in the eastern Italian Alps. On the other hand, his paternal lineage is still observed in Europe, and new male relatives, alive and well, may be possibly added to the list of the mummy’s descendants.
The announcement comes a week after researchers published the results of a genetic analysis which established the Copper Age man was infected with Helicobacter pylori, the pathogen that gives people gastritis and stomach ulcers.
Found in 1991 in a melting glacier in the Oetztal Alps (hence the name), the mummy is one of the most heavily investigated human corpses of all time.
Scientists discovered that Oetzi had brown eyes and very bad teeth, was lactose intolerant, had a genetic predisposition for an increased risk for coronary heart disease and probably had Lyme disease.
It’s certain he died a violent death: In 2007, CT scans showed that an arrowhead had lacerated his left subclavian artery, leading to fast bleeding.
In 2012 a complete analysis of the mummy’s Y chromosome, which is transmitted from fathers to their sons, revealed that Oetzi’s paternal genetic line, named G2a, is still present in modern-day populations.
Questions remained about the Iceman’s maternal lineage, which is named K1f.
“The mummy’s mitochondrial DNA [which is passed from the mother's to her offspring] was the first to be analyzed in 1994,” Valentina Coia, a biologist at the European Academy of Bolzano/Bozen (EURAC), said.
“It was relatively easy to analyze and — along with the Y chromosome — allows us to go back in time, telling us about the genetic history of an individual. Despite this, the genetic relationship between the Iceman’s maternal lineage and lineages found in modern populations was not yet clear,” she said.
To understand whether Oetzi’s genetic maternal line has left its mark in current populations, Coia and EURAC colleagues, in collaboration with the Sapienza University of Rome and the University of Santiago de Compostela, compared the mummy’s mitochondrial DNA with that from 1,077 individuals belonging to the K1 lineage.
Among the samples, 42 originated from the eastern Italian Alps -- in genetic continuity with the mummy.
The comparison revealed that neither the Iceman’s lineage nor any other evolutionarily close lineages are present in modern populations, suggesting that Oetzi’s maternal genetic branch is probably extinct.
“Interestingly, there is a contrast between the Iceman’s maternal and paternal genetic heritage,” the researchers wrote in Scientific Reports, an online open access journal of the Nature group.
“How can this pattern be explained?” they wondered.
To investigate this point, Coia and colleagues compared Oetzi’s mitochondrial DNA and Y chromosome with available data from numerous ancient samples found at 14 different archaeological sites throughout Europe.
It emerged that the Iceman’s paternal lineage was very common in different regions in Europe during the Neolithic age, while his maternal line probably existed only in the eastern Alps.
Putting together the genetic data on the ancient and modern samples, the researchers were able to reconstruct a possible scenario to explain the Iceman’s genetic history: Oetzi’s paternal lineage, G2a, is part of an ancient genetic substrate that arrived in Europe from the Near East with the migrations of the first Neolithic peoples some 8,000 years ago.
Migrations after the Neolithic Age in Europe partially replaced G2a with other lineages, except in geographically isolated areas such as Sardinia.
Read more at Discovery News
But radio astronomers didn’t directly detect the candidate black hole, rather they spied the whirling gases caught in its powerful gravitational grasp, potentially establishing a new method to track down elusive “intermediate-mass” black holes.
Using the Nobeyama 45-meter Radio Telescope, which is managed by the National Astronomical Observatory of Japan (NAOJ), the researchers found the object only 200 light-years from the Milky Way’s supermassive black hole Sagittarius A* (Sgr. A*). By tracking the emissions from a swirling gas cloud called “CO-0.40-0.22,” they found a “surprisingly wide velocity dispersion” — in other words, this cloud of gas is composed of material that is swirling at a wide range of speeds. There appears to be no supernova activity or any other energetic event in the region that could be driving this bizarre phenomenon.
Using computer models, the researchers were able to deduce that an extremely compact object — in other words, a black hole — lives in the “eye” of this interstellar storm and it must be massive. And by “massive” they mean in the order of 100,000 solar masses-massive. If confirmed, this would make the invisible object at the core of CO-0.40-0.22 a so-called “intermediate-mass” black hole, second in mass only to mighty Sgr. A* itself. Sgr. A* “weighs in” at a staggering 4 million solar masses.
“Considering the fact that no compact objects are seen in X-ray or infrared observations, as far as we know, the best candidate for the compact massive object is a black hole,” said Tomoharu Oka, of Keio University in Japan and lead author of a study published in the Astrophysical Journal.
Intermediate-mass black holes are truly mysterious creatures. They are the “missing” link of black hole evolution; we have stellar mass black holes (that form after the supernova death of a massive star) and we have supermassive black holes (that live in the cores of most galaxies), but if black holes start small and grow by merging with other black holes and consuming matter, they must go through a “medium” phase. Alas, astronomers have yet to confirm that black holes do indeed come in “medium” — they’ve only confirmed black holes in sizes “small” and “XXL.”
So that leaves us with a puzzle. Are intermediate-mass black holes simply hard to find? Or are they incredibly rare? The first question may be solved through improved detection techniques, but the second question poses a challenge to black hole evolution theories and could expose a huge flaw in our astrophysical thinking.
Read more at Discovery News
|Bearded vultures tend to stick to mountainous regions, where they have plenty of rocks to drop bones on. Plus, mountains are definitely the most metal of habitats.|
The story is almost certainly not true (that would have been one hell of a shot), but eagles will indeed drop tortoises on rocks like that. There’s even another kind of bird that does the same, only it doesn’t bother with live prey. The beautiful bearded vulture feeds almost exclusively on skeletal fragments, swallowing bones whole when possible. What pieces it can’t swallow it takes into the air and drops onto rocks, shattering them into manageable pieces.
That’s all kinds of clever. Like any other vulture, the bearded variety—which typically flies over mountainous regions of Africa, Asia, and Europe—provides an indispensable service to the ecosystem, checking the spread of disease by consuming corpses. But the bearded’s diet is 95 percent bone. It can wait for the other scavengers to strip the body clean, then stroll in at its leisure to take its fill.
Typically it’s after small to medium ungulates—the hoofed mammals. (It’s also known as the lammergeier, literally “lamb vulture.”) “Anything that’s the size of a domestic sheep,” says ecologist Sonja Krüger of South Africa’s Maloti-Drakensberg Park. “They can swallow the bones of that sized animal quite easily.”
But the bearded vulture isn’t about to pass up the bones of larger animals. Its beak and claws are too weak to break these into small bits, so instead it grabs a bone and hitches a ride on a rising column of air called a thermal. With its supreme vision the vulture targets a patch of rock and lets loose. If its aim is true, it will kill a Greek playwright—or the bone will shatter to pieces on the rock. The bird then swoops in and swallows the shards whole. If it misses, or the bone bounces on impact, the vulture will try again and again until it succeeds.
|The next time someone calls you a vulture, say, “Oh, you mean the beautiful bearded vulture? That eats bone, which is metal as hell?” Then tell the person to walk away before you eat their bones.|
For pretty much every other creature on Earth, bone is indigestible. Hyenas will chew through the odd bone here and there with their powerful jaws, but that’s by no means their main source of food. Owls, which eat things like mice whole, have to regurgitate the bones. Bearded vultures find this unacceptable: They dig bone so much they’ve been known to eat owl throwup.
You might expect that the bearded vulture’s gut would have a problem working through all of this stuff. But its solution is a metric crap-ton of powerful acid. The bird’s digestive system isn’t even elongated to handle the load, nor is there any special grinding going on. Thanks to all that acid, it only takes 24 hours for a bearded vulture to turn solid bone into poop.
And all it eats is bone, day in and day out—save for when two bearded vultures fall in love and have babies. Them feeding their sensitive young ‘uns bone would be like you feeding yours … well, bone, I guess. So “you’ll find adults picking pieces of meat at certain times of the year, and even pieces of fat, off the carcass to get [the chicks] into breeding condition,” says Krüger.
But if the bearded vulture is clearly capable of eating meat, why go through all the trouble of eating bone? Two reasons. For one, nothing else, save for the occasional hyena, is going to bother with the stuff, and that’s a huge advantage when it comes to survival. And secondly, unlike other scavengers that have to consume a corpse before it spoils, the bearded vulture can and does return to skeletons time after time to cart away bones. So in effect it keeps pantries scattered across the mountains.
|Vultures play a pivotal role in ecosystems as the cleanup crew. Think of them like janitors. Or don’t. Doesn’t matter to me.|
From all these photos of the bearded vulture you may have noticed that the bird actually has feathers on its noggin, which vultures normally don’t, and that those feathers are a beautiful red hue, or burnt sienna if you don’t have problems determining subtle colors like me.
Those feathers are there because they can be. The bearded vulture just doesn’t eat like other vultures. “The others don’t have feathers on their heads so they can get into the carcasses and it won’t get matted with all the liquid or blood,” says Krüger. That helps spare them the inconvenience of carrying around diseases. Because the bearded vulture swoops in later to pick up the bones, it can afford keeping a luxurious head of feathers.
As for the color, they actually apply it by rubbing themselves against cliffs and rolling around in the mud. “It’s that iron oxide in the soil that gives them that color,” says Krüger. “Birds that are in captivity for a long time that aren’t provided with the facility to have a mud bath, they’re basically snow white.”
So what’s the point? One theory holds that it’s a signal of strength—well, at least it’s a roundabout signal. Theoretically, the birds with the most deeply stained feathers spend the most time rolling in the mud. This would signal to potential mates that they’re more fit because they’re feeding well enough to have the time to fart around.
But a more likely theory, according to Krüger, is that the mud helps keep parasites at bay. An additional bonus may be that the vulture picks up minerals from the mud as it preens itself, like it’s wearing a coat of multivitamins.
Read more at Wired Science
Jan 13, 2016
The frogs (Hylodes japi) could have the most complex communication system of any amphibian, suggests the paper, published in the journal PLOS ONE.
Fábio Perin de Sá of Sao Paulo State University and colleagues wrote that the communication of the frogs “is undoubtedly more sophisticated than we expected and that visual communication in anurans (tailless amphibians) is more widespread than previously thought.” They added that “this is especially true in tropical regions,” likely because of the higher number of frog species there and ecological factors, such as diverse microhabitats.
The following three videos, which run in sequence, illustrate only some of the frog's skills, such as singing like a bird and doing leg displays.
De Sá and his team made the recordings in the biological reserve of Serra do Japi in the state of Sao Paulo, southeastern Brazil. The forested region provides important habitat for many species of plants and animals.
The researchers documented the calls as well as the visual displays of the frogs. The latter consisted of toe trembling, toe flagging (which reveals the frog’s silver-white underside), foot shaking, hand shaking, arm waving, head bobbing, full body jerks, and much more.
A particularly complex move is the "head snake." Males seem to use this to mesmerize females. While approaching prospective mates, the males will move their heads from side to side as snakes do when in front of a snake charmer. The males do this looking right into the eyes of the desired female and at very close range, but not touching her.
Actual courtship is quite a scene. While peeping and squealing, the males tremble their toes, engage in toe flagging, foot shaking, hand shaking, arm lifting, head bobbing, body jerking and perform throat displays. While all of this is going on, the females remain motionless. Only later, with a subtle lift of an arm as if to say, "Yoo hoo, I'm ready," does a female often signal her willingness to mate. She then rubs part of her body on the male's back, with her hands gently touching him. Intercourse usually starts thereafter.
The scientists also observed that females could stimulate males to emit courtship calls with just a lift of their arm, most often the left one. Such control has never been documented before in frogs.
Read more at Discovery News
Named Machimosaurus rex, this croc would have weighed in at least 6,600 pounds and been around 32 feet long. Other than its size, it would have looked much like a modern day crocodile except for its narrow snout – which was designed to allow it swim in the ocean.
It would have been the top predator in what was then an ocean that separated Africa from Europe about 130 million years ago.
“This is an incredibly big crocodile. It is twice as big as a present day marine crocodile,” University of Bologna’s Federico Fanti, who was part of the team that made the discovery with support from the National Geographic Society Committee for Research and Exploration, told FoxNews.com.
“The skull itself is as big I am,” said Fanti, whose discovery was detailed in a study in the journal Cretaceous Research. “Just the skull is more than five feet long. It’s a massive crocodile.”
Tunisia, where the skeleton and some bones were found, would have been a lagoon facing the ocean and the environment would have been filled with huge fish and turtles – all favorite prey of the Machimosaurus rex.
“This animal, however, used to feast on the large turtles or big fishes that it found in the ocean,” Fanti said. “He was so big and so powerful that it was absolutely at the top of the food chain.”
Beyond its size, Fanti said the significance of the find is what it tells us about a mass extinction event that is believed to have happened between the Jurassic and Cretaceous period about 150 million years ago. Machimosaurus rex was thought to have died out then but the discovery suggests the extinction event was not as widespread as some paleontologist thought.
“The fact that Machimosaurus rex (pertaining to a group that was well alive in the Jurassic) lived 130-120 million years ago indicate that there was no mass extinction,” Fanti said.
“Everyone thought this group of crocodiles went extinct in the Jurassic but we found it well into the Cretaceous,” he said. “We simply extended the temporal range of the animals. Twenty million years is a lot of time.”
Read more at Discovery News
The bacteria, Yersinia pestis, played a major role in two historical pandemics, which killed millions of people.
The first was the so-called Justinian plague, named after the Byzantinian emperor Justinian I, and occurred from the 6th to 8th century.
The second pandemic spread between the 14th and the 17th century. In Europe it peaked in the years 1346–53, a period known as the “Black Death,” in which almost one third of the entire population was wiped out.
Although molecular DNA analysis of archaeological skeletal material have confirmed the role of Y. pestis in both pandemics, researchers still don’t know how the pandemics could have continued for several hundred years.
According to one theory, the bacteria may have been continuously reintroduced from central Asia to Europe in several waves along major trade routes, such as the Silk Road. Another hypothesis assumes Y. pestis existed in Europe for centuries in a yet unidentified host.
A team of German researchers investigated both hypothesis by analyzing 30 victims of the second plague pandemic. The remains were excavated from two different burial sites in Germany, and covered a time span of roughly 300 years.
If the bacteria were reintroduced from central Asia in multiple waves, “various different genotypes, reflecting the natural genetic diversity of Asian Y. pestis strains, should be detectable among different plague victims,” Lisa Seifert, from Ludwig Maximilian University of Munich, and colleagues argued in the open-access journal PLOS ONE.
On the contrary, if there were unknown and persistent reservoirs, identical or very similar genotypes should be present in plague victims from different time periods of both pandemics.
Among the 300–600 year-old human remains, eight people were positive for Y. pestis-specific nucleic acid.
The genetic material from victims testing positive was highly similar to previously investigated plague victims from other European countries and had the identical Y. pestis genotype.
“This is why we assume that a certain genotype may have persisted for some 300 years in Europe,” Holger Scholz, at the Bundeswehr Institute of Microbiology in Munich, Germany, told Discovery News.
Besides the assumed, continuous reintroduction of Y.pestis from central Asia in multiple waves during the second pandemic, it's possible that the bacteria lasted such a long time in Europe in a yet unknown host, the researchers wrote.
Read more at Discovery News
Located in Acidalia Planitia, a region dominated by a plain north of the Martian equator, this river apparently flowed from right to left, down the slope of a crater rim and into the crater itself. This image was captured by the prolific High-Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance Orbiter (MRO) on Sept. 25, 2015.
It is not known how long the water flowed in this ancient river, nor its source, only that liquid water channels converged to rush down the crater rim, meandering into the plain below. This particular “dendric” river channel is composed of many smaller tributaries that fed the primary channel, according to Mike Mellon of the HiRISE team.
It is not fully understood how rivers such as these were sourced — whether by sub-surface aquifers, meltwater or even rainfall — but through studies of the long-lost rivers of Mars from orbit we can supplement studies by surface missions (such as NASA’s Mars rovers Curiosity and Opportunity) to help us piece together the puzzle of Mars’ wet past.
From Discovery News
Jan 12, 2016
The excavation, carried out at a quarry in Peterborough by Historic England and the University of Cambridge, provides an extraordinary insight into domestic life 3,000 years ago.
Dating to the end of the Bronze Age (1200-800 BC), the settlement was home to several families who lived in a number of circular wooden houses built on stilts above a river.
A fire destroyed the settlement causing the houses to fall into the river, where silt and clay preserved the contents.
“It’s a frozen moment in time,” Duncan Wilson, Chief Executive of Historic England, said.
“We are learning more about the food our ancestors ate, and the pottery they used to cook and serve it … This site is of international significance and its excavation really will transform our understanding of the period,” he added.
Archaeologists found an extraordinary time capsule buried just over six feet below the ground surface, where the river bed actually was in 1000-800 BC. It contained textiles, small cups, bowls and jars complete with past meals still inside.
Such is the level of preservation that the footprints of those living there are still visible in the waterlogged sediments.
The archaeologists also found exotic glass beads that were part of an elaborate necklace, suggesting “a sophistication not usually associated with the British Bronze Age,” Cambridge Archaeological Unit said in a statement.
The way the objects were found indicate people were forced to leave everything behind when fire caught on the houses. It is not known yet whether it was an accident or fire was set deliberately by hostile forces.
The archaeologists expect to find much more as the excavation, which is now half way through the four-year project, continues over the coming months.
Read more at Discovery News
The tomb holds the man and a younger woman, who may or may not have known the male occupant, scientists say.
“The excavators soon came to find that the left leg of the male occupant is deformed, with the patella, femur and tibia together and fixed at 80 ,” archaeologists wrote in a paper published recently in the journal Chinese Archaeology.
The fused knee would have made it hard for the man to walk or ride horses without the prosthetic leg, the researchers found. The man couldn’t straighten his left leg out so the prosthetic leg, when attached, allowed the left leg to touch the floor when walking. The horse hoof at the bottom of the prosthetic leg acted like a foot.
The prosthetic leg was “made of poplar wood; it has seven holes along the two sides with leather tapes for attaching it to the deformed leg,” the archaeologists wrote. “The lower part of the prosthetic leg is rendered into a cylindrical shape, wrapped with a scrapped ox horn and tipped with a horsehoof, which is meant to augment its adhesion and abrasion.”
“The severe wear of the top implies that it has been in use for a long time,” they added.
Radiocarbon dating indicates that the tomb in Turpan (also spelled Turfan) dates back around 2,200 years. The only other known prosthetic leg in the world that dates to that time is part of a bronze leg found in Capua, Italy. That leg was destroyed in a bombing raid during World War II. Prosthetic toes, dating to earlier times, have been found in Egypt.
Who used it?
Two other studies, published in the journals Bridging Eurasia and Quaternary International, provide more details about the man who used the hoofed leg. Researchers estimate that the man was about 5 feet 7 inches (1.7 meters) tall, and between 50 and 65 years old when he died.
What caused the odd fusion of his left knee joint? “Different causes, like inflammation in or around the joint, rheumatism or trauma, might have resulted in this pathological change,” archaeologists wrote in the journal Bridging Eurasia.
Researchers found evidence that the man was infected with tuberculosis at some point in his life. They think that inflammation from the infection may have resulted in a bony growth that allowed his knee to fuse together. “The smooth surface of the bones affected by the ankyloses [joint fusion] suggests the active inflammatory process stopped years before death,” the researchers wrote in Bridging Eurasia.
The man appears to have been a person of modest means, as he was buried with nonluxurious items: ceramic cups and a jar, a wooden plate and wooden bows, the archaeologists found. Sometime after he died, his tomb was reopened, and the body of a 20-year-old woman was put in, disturbing the man’s bones. What relationship the man and woman had (if any) is unknown. The tomb was one of 30 that archaeologists excavated in the cemetery.
Based on the results of the radiocarbon dating, “the occupants of the cemetery might have belonged to the Gushi [also spelled Jushi] population,” archaeologists wrote in the Chinese Archaeology article.
Little is known about these people. Ancient Chinese texts suggest that the Gushi had a small state. “As recorded in the Xiyu zhuan (the Account of the Western Regions) of the Hanshu (Book of Han, by Ban Gu), during the middle of the Western Han, there lived in the Turfan Basin the Gushi population, who constitutes one of the ‘Thirty-six States of the Western Regions’ of the Qin and Han Dynasties,” the archaeologists wrote.
The Gushi state was conquered by China’s Han Dynasty during a military campaign in the first century B.C., according to ancient records. “Given that the study of the Gushi culture is yet at its nascent stage, the provides valuable new materials,” the archaeologists wrote.
Read more at Discovery News
In a newly published article in the scientific journal Nature, researchers from Great Britain’s Bristol University shed new light on the process by which the Earth’s recycling of carbon through plate subduction, in which the edge of one plate slides under the edge of another plate, and how that process forms so-called superdeep diamonds.
The researchers, who experimented with small samples of synthetic ocean floor rock at high pressures and temperatures, found that those slabs released most of their carbon at conditions equivalent to depths of 186 to 435 miles below the Earth’s surface.
In addition, the researchers tested the reaction of the melted slabs with the mantle. They were able to reproduce the mineral makeup observed in superdeep diamonds, which generally form at depths of below 155 miles.
The research not only provides an explanation for how superdeep diamonds are formed, but shows that they essentially are a snapshot of the deepest portions of the Earth’s carbon cycle. That makes them a useful tool for understanding what goes on inside our planet.
“One of the most amazing ideas that comes from this work is that superdeep diamonds are like marathon runners that have just crossed the finish line,” Bristol scientist Andrew R. Thomson explained in a press release.
"The difference in this case is the diamonds have just completed one of the most mind baffling journeys possible, from the ocean floor to around 700 km (435 miles) depth and back to the surface," he said. "Fortunately for scientists, their mineral inclusions are like stopwatches recording the entire journey, and with further work we will hopefully reveal many more remarkable secrets about their epic journey.”
As Thomson’s colleague Simon Kohn added: “Superdeep diamonds hold great potential for future research on the Earth’s volatile cycles, and we now know much more about the fundamental process that forms them. We will be able to use the wealth of information that is trapped inside the diamonds to build a detailed picture of processes occurring hundreds of kilometers beneath our feet.”
Read more at Discovery News
In a tweet by Lawrence Krauss this morning, the well-known Arizona State University theoretical physicist and cosmologist wrote: “My earlier rumor about LIGO has been confirmed by independent sources. Stay tuned! Gravitational waves may have been discovered!! Exciting.”
In September, Krauss hinted that LIGO — the Laser Interferometer Gravitational Wave Observatory — had detected signs of elusive gravitational waves. “Rumor of a gravitational wave detection at LIGO detector. Amazing if true. Will post details if it survives,” he tweeted on Sept. 28, 2015.
The detector, which is split between two locations in Louisiana and Washington, has recently undergone a sensitivity upgrade, so hopes are high that the hard-to-find space-time wiggles may finally be directly detected, perhaps heralding a new era of gravitational wave astronomy.
It is thought that any acceleration of massive objects in the universe will generate gravitational waves. Black hole and neutron star collisions, supernovae and galactic mergers are all thought to be huge sources of gravitational waves; if we can somehow detect and, indeed, map them we could reveal some of the most massive objects and most energetic events in the cosmos.
The theoretical basis for gravitational waves spawn from general relativity equations that were formulated by Albert Einstein over 100 years ago. Although there is indirect evidence of gravitational waves carrying away energy from orbiting bodies (through extended observations of binary pulsar and white dwarf systems), the detection of the extremely slight impact of the propagation of gravitational waves that are hypothetically washing though our planet has been maddeningly difficult to achieve.
The LIGO stations use extremely fine-tuned laser interferometers to detect the passage of gravitational waves (that can be imagined as ripples in spacetime, much like the ripples that propagate across the surface of a pond) and only weeks before Krauss’ original tweeted rumor had embarked on a new phase of sophistication, called Advanced LIGO.
Now, Krauss may well be directly involved with the analysis of LIGO data and he could be privy to an exciting finding that may indicate a LIGO detection of gravitational waves, but until rigorous 3rd party studies are completed and studies are published in peer reviewed journals, it is hard to make solid conclusions about what has (or indeed hasn’t) been discovered by LIGO.
As pointed out by Jennifer Ouellette at Gizmodo, until we get any official word from LIGO, we just have to be patient and avoid jumping the gun when hearing rumors circulating on social media.
Gravitational waves haven’t been far from the headlines in recent years. In 2014, announcements were made that the South Pole-based telescope BICEP2 had detected signals in the cosmic microwave background (CMB) of primordial gravitational waves, thereby confirming some Big Bang and inflationary models. However, the announcement was made prematurely and it quickly became clear that the BICEP2 signal was a dud. Observations by the European Planck space telescope revealed that, in fact, the signal was caused by obscuring dust in our galaxy, not by gravitational waves etched into radiation generated at the furthest-most reaches of the universe. Bummer.
Even scientists can let excitement get the better of them, and while rumors are a part of human nature, social media rapidly boosts the virility of these rumors that can quickly be misconstrued as fact.
Read more at Discovery News
Jan 11, 2016
Test batteries incorporating this cathode material exhibited improved high-voltage cycling behavior--the kind you'd want for fast-charging electric vehicles and other applications that require high-capacity storage. The scientists describe the micro-to-nanoscale details of the cathode material in a paper published in the journal Nature Energy January 11, 2016.
"Our colleagues at Berkeley Lab were able to make a particle structure that has two levels of complexity where the material is assembled in a way that it protects itself from degradation," explained Brookhaven Lab physicist and Stony Brook University adjunct assistant professor Huolin Xin, who helped characterize the nanoscale details of the cathode material at Brookhaven Lab's Center for Functional Nanomaterials.
X-ray imaging performed by scientists at the Stanford Synchrotron Radiation Lightsource (SSRL) at SLAC along with Xin's electron microscopy at CFN revealed spherical particles of the cathode material measuring millionths of meter, or microns, in diameter made up of lots of smaller, faceted nanoscale particles stacked together like bricks in a wall. The characterization techniques revealed important structural and chemical details that explain why these particles perform so well.
The lithium ion shuttle
Chemistry is at the heart of all lithium-ion rechargeable batteries, which power portable electronics and electric cars by shuttling lithium ions between positive and negative electrodes bathed in an electrolyte solution. As lithium moves into the cathode, chemical reactions generate electrons that can be routed to an external circuit for use. Recharging requires an external current to run the reactions in reverse, pulling the lithium ions out of the cathode and sending them to the anode.
Reactive metals like nickel have the potential to make great cathode materials--except that they are unstable and tend to undergo destructive side reactions with the electrolyte. So the Brookhaven, Berkeley, and SLAC battery team experimented with ways to incorporate nickel but protect it from these destructive side reactions.
They sprayed a solution of lithium, nickel, manganese, and cobalt mixed at a certain ratio through an atomizer nozzle to form tiny droplets, which then decomposed to form a powder. Repeatedly heating and cooling the powder triggered the formation of tiny nanosized particles and the self-assembly of these particles into the larger spherical, sometimes hollow, structures.
Using x-rays at SLAC's SSRL, the scientists made chemical "fingerprints" of the micron-scale structures. The synchrotron technique, called x-ray spectroscopy, revealed that the outer surface of the spheres was relatively low in nickel and high in unreactive manganese, while the interior was rich in nickel.
"The manganese layer forms an effective barrier, like paint on a wall, protecting the inner structure of the nickel-rich 'bricks' from the electrolyte," Xin said.
But how were the lithium ions still able to enter the material to react with the nickel? To find out, Xin's group at the CFN ground up the larger particles to form a powder composed of much smaller clumps of the nanoscale primary particles with some of the interfaces between them still intact.
"These samples show a small subset of the bricks that form the wall. We wanted to see how the bricks are put together. What kind of cement or mortar binds them? Are they layered together regularly or are they randomly oriented with spaces in between?" Xin said.
Nanoscale details explain improved performance
Using an aberration-corrected scanning transmission electron microscope--a scanning transmission electron microscope outfitted with a pair of "glasses" to improve its vision--the scientists saw that the particles had facets, flat faces or sides like the cut edges of a crystal, which allowed them to pack tightly together to form coherent interfaces with no mortar or cement between the bricks. But there was a slight misfit between the two surfaces, with the atoms on one side of the interface being ever so slightly offset relative to the atoms on the adjoining particle.
"The packing of atoms at the interfaces between the tiny particles is slightly less dense than the perfect lattice within each individual particle, so these interfaces basically make a highway for lithium ions to go in and out," Xin said.
Like tiny smart cars, the lithium ions can move along these highways to reach the interior structure of the wall and react with the nickel, but much larger semi-truck-size electrolyte molecules can't get in to degrade the reactive material.
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The seeds are miniscule — the largest was no more than 0.1 inch (2.5 millimeters) in diameter — and unusually well-preserved, in such good condition that their internal cell structures were still visible. For the first time, scientists were able to detect seed embryos, the part of the seed where a new plant grows and emerges, and food storage tissues surrounding them. These structures offered a rare glimpse into how the Cretaceous seeds grew, and how they compare with plants alive today.
Else Marie Friis, lead author of the study and professor emerita at the Swedish Museum of Natural History, has analyzed some of these fossil remains of angiosperms — flowering plants — preserved in soils in Portugal and North America. She and her colleagues used a relatively new visualization technique — synchrotron radiation X-ray tomographic microscopy (SRXTM), which allowed them to explore the delicate fossils without damaging or destroying them. They imaged 250 seeds spanning 75 different species (some were also different genera), revealing the embryos and nutrient structures inside the seeds in exquisite detail.
Around half of the fossil seeds they examined contained preserved cell structures within their seed coats, and about 50 seeds held partial or complete embryos. Once they had 2D images of the embryos, they used software to model the embryos’ shapes in 3D, finding that their size and shape varied between seeds. In some cases, the embryos resembled those in modern plants believed to be distant relatives of the Cretaceous angiosperms.
“These observations give us new insights into the early part of the life cycle of early angiosperms, which is important for understanding the ecology of flowering plants during the emergence and dramatic radiation through the early Cretaceous,” Friis said in a video statement.
During the Cretaceous period, angiosperms evolved and diversified rapidly. Many new insect species, which also appeared during the Cretaceous, may have played a part in how quickly flowering plants took hold and thrived in the ancient landscape.
Read more at Discovery News
Bowie died on Sunday surrounded by family, according to his social media accounts.
The iconic musician had turned 69 only on Friday, which coincided with the release of "Blackstar", his 25th studio album.
"David Bowie died peacefully today (Sunday) surrounded by his family after a courageous 18 month battle with cancer," said a brief statement posted to both his Twitter and Facebook accounts.
"While many of you will share in this loss, we ask that you respect the family’s privacy during their time of grief," it added.
Film director Duncan Jones, Bowie's son with his first wife Angela Bowie, confirmed the news on Twitter.
"Very sorry and sad to say it's true. I'll be offline for a while. Love to all," Jones wrote on his official account.
The death brings the curtain down on one of the most acclaimed artists of modern British music, with a career dating back to the hit "Space Oddity" in 1969, about an astronaut called Major Tom, who is abandoned in space.
It spanned styles ranging from glam rock, New Romantic, Krautrock and dance music to alternative rock, jungle, soul and hard rock, underpinned by an astonishing array of stage personas from the sexually ambiguous Ziggy Stardust to the so-called Thin White Duke.
He was born David Robert Jones in Brixton, inner south London on January 8, 1947, before his family moved out to the leafy suburb of Bromley when he was six.
Master of Reinvention
In the first of many re-inventions, he named himself David Bowie in 1966 to avoid confusion with Davy Jones, lead singer with Beatles rivals The Monkees, and studied Buddhism and mime.
The 1970s -- the decade that saw him dominate the British music scene and conquer the United States -- brought forward a string of successful albums.
It began with the critically acclaimed "Hunky Dory", continued with "The Rise and Fall of Ziggy Stardust and the Spiders from Mars" -- whose hits included "Starman" and "Suffragette City" -- followed by the rock album "Aladdin Sane", the apocalyptic "Diamond Dogs" and a fling with so-called plastic soul, "Station to Station."
He then switched gears once more, moving to Berlin to work with the electronic experimentalist Brian Eno product a trio of albums -- "Low", "Heroes" and "Lodger".
Read more at Discovery News
As expected, the analysis shows the galaxy’s central disk formed from the inside out, with red giant stars as old as about 13 billion years clustered toward the center and younger stars about 1 billion years old closer to the disk’s edge, astronomer Melissa Ness, with the Max Planck Institute for Astronomy in Heidelberg, Germany, told reporters at the American Astronomical Society meeting in Kissimmee, Florida.
“What we’re able to do … is understand how our galaxy has formed in detail, looking at the dispersion of ages, the gradient of the ages, how the ages change as a function of both the height from the (disk’s) plane and the radius," Ness said. "It’s understanding the details of this inside-out formation that is now possible."
Unique to the survey is its age-dating technique, which is based on a star’s size. Ness and colleagues used high-quality Sloan survey spectra, which reveals a star’s chemistry, with optical data collected by NASA’s Kepler space telescope to develop a model that can be used to pinpoint a star’s age.
“This is somewhat revolutionary because ages have previously been considered very hard to get, particularly from stellar spectra. They’re important, but they’re difficult,” Ness said.
The key was a newly discovered relationship between a star’s age and its ratio of carbon-to-nitrogen, concentrations of which can be ferreted out by analyzing a star’s spectra.
Read more at Discovery News
Jan 10, 2016
But the Idaho Department of Fish and Game has confirmed that the young male mountain lion legally shot south of Preston had a growth on its head with a full set of fangs.
The growth, which hints at the snout of another cougar, had small whiskers as well.
It came to the department’s attention after it was shot at by a landowner, who saw it attacking a neighbor’s dog. Although the mountain lion ran off, the hunter followed it into the hills with his hounds and eventually killed it.
The hunter had a valid license and tag and had reported it to the conservation office as required by law.
According to biologists at the Idaho Fish and Game, the growth could be the result of a conjoined twin that died in the womb. Sometimes the surviving fetus will absorb the tissue of the twin into its own.
Another explanation is that it could be a teratoma tumor, a growth composed of tissue that makes up teeth, hair, and even fingers and toes. These tumors are rare, but have been seen before in humans and animals.
Whatever the case, the site of the animal is both frightening and sad. Although it had survived into young adulthood, it’s unclear if the cougar suffered from the tumor.
The hunter is not required to hand over the carcass to the conservation office.
From Discovery News
The researchers, led by TeYu Chien, a UW assistant professor in the Department of Physics and Astronomy, determined that the electric field is responsible for alterating the fracture toughness of nanomaterials, which are used in state-of-the-art electronic devices. It is the first observed evidence that the electric field changes the fracture toughness at a nanometer scale.
This finding opens the way for further investigation of nanomaterials regarding electric field-mechanical property interactions, which is extremely important for applications and fundamental research.
Chien is the lead author of a paper, titled "Built-in Electric Field Induced Mechanical Property Change at the Lanthanum Nickelate/Nb-doped Strontium Titanate Interfaces," that was recently published in Scientific Reports. Scientific Reports is an online, open-access journal from the publishers of Nature. The journal publishes scientifically valid primary research from all areas of the natural and clinical sciences.
Other researchers who contributed to the paper are from the University of Arkansas, University of Tennessee and Argonne National Laboratory in Argonne, Ill.
Chien and his research team studied the surfaces of the fractured interfaces of ceramic materials, including lanthanum nickelate and strontium titanate with a small amount of niobium. The researchers revealed that strontium titanate, within a few nanometers of the interfaces, fractured differently from the strontium titanate away from the interfaces.
The two ceramic materials were chosen because one is a metallic oxide while the other is a semiconductor. When the two types of materials come into contact with each other, an intrinsic electric field will automatically be formed in a region, known as the Schottky barrier, near the interface, Chien explains. The Schottky barrier refers to the region where an intrinsic electric field is formed at metal/semiconductor interfaces.
The intrinsic electric field at interfaces is an inevitable phenomenon whenever one material is in contact with another. The electric field effects on the mechanical properties of materials are rarely studied, especially for nanomaterials. Understanding electric field effects is extremely important for applications of nanoelectromechanical system (NEMS), which are devices, such as actuators, integrating electrical and mechanical functionalities on the nanoscale.
For NEMS materials made in nanoscale, understanding the mechanical properties affected by electric fields is crucial for full control of device performance. The observations in this study pave the way to better understand the mechanical properties of nanomaterials.
"The electric field changes the inter-atomic bond length in the crystal by pushing positively and negatively charged ions in opposite directions," Chien says. "Altering bond length changes bond strength. Hence, the mechanical properties, such as fracture toughness."
Read more at Science Daily
Their conclusions, reported Jan. 8 at the American Astronomical Society meeting in Kissimmee, Florida, clarify why quasar SDSS J1011+5442 changed so dramatically in the handful of years between observations.
"We are used to thinking of the sky as unchanging," said University of Washington astronomy professor Scott Anderson, who is principal investigator of the SDSS's Time-Domain Spectroscopic Survey. "The SDSS gives us a great opportunity to see that change as it happens."
Quasars are the compact area at the center of large galaxies, usually surrounding a massive black hole. The black hole at the center of J1011+5442, for example, is some 50 million times more massive than our sun. As the black hole gobbles up superheated gas, it emits vast amounts of light and radio waves. When SDSS astronomers made their first observations of J1011+5442 in 2003, they measured the spectrum of the quasar, which let them understand the properties of the gas being swallowed by the black hole. In particular, the prominent "hydrogen-alpha" line in the spectrum revealed how much gas was falling into the central black hole.
The SDSS measured another spectrum for this quasar in early 2015, and noticed a huge decrease between 2003 and 2015. The team made use of additional observations by other telescopes over those 12 years to narrow down the period of change.
"The difference was stunning and unprecedented," said UW astronomy graduate student John Ruan, a member of the research team. "The hydrogen-alpha emission dropped by a factor of 50 in less than 12 years, and the quasar now looks like a normal galaxy."
The change was so great that throughout the SDSS collaboration and astronomy community, the quasar became known as a "changing-look quasar." The black hole is still there, of course, but over the past 10 years, it appears to have swallowed all the gas in its vicinity. With the gas fallen into the black hole, the SDSS team were unable to detect the spectroscopic signature of the quasar.
"This is the first time we've seen a quasar shut off this dramatically, this quickly," said lead author Jessie Runnoe, a postdoctoral researcher at Pennsylvania State University.
Before Runnoe, Ruan and their colleagues could come to this conclusion, they had to rule out two other possibilities. A thick layer of dust could have passed through the host galaxy, obscuring their view of the black hole at its center. But, they concluded that there is no way that any dust cloud could have moved fast enough to cause a 50-fold drop in brightness in just two years. Another possibility is that the bright quasar in 2003 was just a temporary flare caused by the black hole ripping apart a nearby star. While this possibility has been invoked in similar cases, it cannot to explain the fact that the changing-look quasar had been shining for many years before it turned off.
The team's conclusion is that the quasar has used up all the glowing-hot gas in its immediate vicinity, leading to a rapid drop in brightness.
"Essentially, it has run out of food, at least for the moment," says Runnoe. "We were fortunate to catch it before and after."
Read more at Science Daily