Oct 11, 2014
The rescued antiquities include a beautiful intact table jug, part of an ornate bed leg, ship components, and a giant bronze spear that would have belonged to a life-sized warrior statue.
Dubbed the “Titanic of the ancient world,” the vessel sank more than 2,000 years ago off the remote island of Antikythera, in southern Greece. The ship, which dates from 70-60 B.C., was probably smashed against the island’s sheer cliffs during a violent storm.
The wreck, believed to have been a Roman commercial vessel that was carrying a luxury cargo of Greek treasures from the coast of Asia Minor west to Rome, was found by Greek sponge divers more than 100 years ago.
At that time the divers retrieved a treasure hoard which included bronze and marble statues, jewelry, furniture and the mysterious “Antikythera mechanism” — a complex, geared astronomical calculator known as the world’s oldest computer.
But scouring the treacherous wreck site, 180 feet down a steep underwater slope, proved dangerous and explorations were halted.
A new project of the Greek Ministry of Culture and the Woods Hole Oceanographic Institution has allowed divers to return to the Antikythera shipwreck using a state-of-the art exosuit that acts like a wearable submarine.
The Iron Man-like diving suit allows divers to delve to depths of up to 1,000 feet and stay underwater for up to three hours at a time — without being at risk of decompression sickness.
During their first excavation season, from Sept. 15 to Oct. 7, 2014, the researchers were able to create a high-resolution, 3-D map of the site using stereo cameras mounted on an autonomous underwater vehicle (AUV).
A series of finds recovered by divers revealed promising future developments.
“Components of the ship, including multiple lead anchors over a meter long and a bronze rigging ring with fragments of wood still attached, prove that much of the ship survives,” the Woods Hole Oceanographic Institution said in a statement.
The researchers realized the finds are scattered over a large area, covering 984 feet (300 meters) of the seafloor.
This, together with the huge size of the anchors and hull planks, indicate the Antikythera ship was much larger than previously thought, perhaps up to 164 feet long.
“The evidence shows this is the largest ancient shipwreck ever discovered,” marine archaeologist Brendan Foley of the Woods Hole Oceanographic Institution said.
“It’s the Titanic of the ancient world,” he added.
Among the artifact recovered, the most promising for future discoveries is a 6 1/2 foot-long bronze spear.
Too large and heavy to have been used as a weapon, it most likely belonged to a colossal statue — perhaps a warrior or the goddess Athena.
Read more at Discovery News
According to a report in the “Mail and Guardian:”
“‘They were attacked and burnt to death by a mob of villagers who accused them of engaging in witchcraft,’ the police chief for the western Kigoma region, which borders Burundi, Jafari Mohamed, told Agence France-Presse… Among those arrested on suspicion of carrying out the killings was the local traditional healer, or witchdoctor.”
The victims, most of whom were elderly, were burned alive and in some cases hacked to death with machetes. Nearly two dozen people were arrested, and the fact that a witch doctor was among them is not unusual.
Throughout Africa belief in witches is common, and black magic is considered a normal part of everyday life. A 2010 poll of 18 countries in sub-Saharan Africa found that over half of the population believe in magic. Witch doctors are consulted not only for healing diseases, but also for placing, or removing, curses or bringing luck. It is not unusual for people to consult witch doctors seeking magical assistance when preparing for a job interview, starting a business or seeking a mate.
It’s not clear what sparked the attack, but often witchcraft accusations follow some unexplained misfortune such as an accident, a sudden sickness or a village drinking well drying up. If there is no obvious, immediate explanation, the event may be blamed on a suspected witch — usually women and the elderly. Other times the witchcraft accusations are used as a pretext to settle personal grudges or confiscate the victim’s property.
Witchcraft persecutions have been prevalent in East Africa and especially Tanzania. In May of this year an albino woman in a rural Tanzania was murdered for her body parts. Two witch doctors were arrested in connection with her death. Though she was not accused of witchcraft, she was killed for it. The belief and practice of using body parts for magical ritual or benefit is called muti. Muti murders are particularly brutal, with knives and machetes used to cut and hack off limbs, breasts and other body parts from their living victims.
Belief in, and persecution of, witches is universal and dates back millennia. Often all that is needed is a belief in magic, though sometimes witchcraft is prohibited by organized religion. The Christian bible, for example, explicitly calls for accused witches to be put to death per Exodus 22:18, which states, “Thou shalt not suffer a witch to live” (KJV). The passage seems crystal clear in its murderous command to kill witches — but there’s a problem.
Read more at Discovery News
Oct 10, 2014
The shape of living organisms evolves over time. The questions raised by this transformation have led to the emergence of theories of evolution. To understand how biological shapes change over a geological time scale, researchers have recently begun to investigate how they are generated during an individual's development and growth: this is known as morphogenesis. Due to the exceptional diversity of their shell shapes and patterns (particularly the ribs), ammonites have been widely studied from the point of view of evolution but the mechanisms underlying the coiled spirals were unknown until now. Researchers therefore attempted to elucidate the evolution of these shapes without knowing how they had emerged.
Régis Chirat and his team have developed a model that explains the morphogenesis of these shells. By using mathematical equations to describe how the shell is secreted by ammonite and grows, they have demonstrated the existence of mechanical forces specific to developing mollusks. These forces depend on the physical properties of the biological tissues and on the geometry of the shell. They cause mechanical oscillations at the edge of the shell that generate ribs, a sort of ornamental pattern on the spiral.
By examining various fossil specimens in light of the simulations produced by the model, the researchers observed that the latter can predict the number and shape of ribs in several ammonites. The model shows that the ornamentation of the shell evolves as a function of variables such as tissue elasticity and shell expansion rate (the rate at which the diameter of the opening increases with each spiral coil).
By providing a biophysical explanation for how these ornamentations form, this theoretical approach explains the diversity existing within and between species. It thus opens new perspectives for the study of the morphological evolution of ammonites, which seems to be largely governed by mechanical and geometric constraints. This new tool also sheds light on an old mystery. For almost 200 million years, the shells of nautili, distant "cousins" of ammonites, have remained essentially smooth and free of distinctive ornamentation. The model shows that having maintained this shell shape does not mean that nautili -- wrongly referred to as "living fossils" -- have not evolved, but is due to a high expansion rate, leading to the formation of smooth shells that are difficult to distinguish from one another.
Read more at Science Daily
The anthropological investigation examined 350 bones and fragments found in two larnakes, or caskets, of the tomb. It uncovered pathologies, activity markers and trauma that helped identify the tomb's occupants.
Along with the cremated remains of Philip II, the burial, commonly known as Tomb II, also contained the bones of a woman warrior, possibly the daughter of the Skythian King Athea, Theodore Antikas, head of the Art-Anthropological research team of the Vergina excavation, told Discovery News.
The findings will be announced on Friday at the Archaeological Museum of Thessaloniki. Accompanied by 3,000 digital color photographs and supported by X-ray computed tomography, scanning electron microscopy, and X-ray fluorescence, the research aims to settle a decades-old debate over the cremated skeleton.
Scholars have argued over those bones ever since Greek archaeologist Manolis Andronikos discovered the tomb in 1977-78. He excavated a large mound -- the Great Tumulus -- at Vergina on the advice of the English classicist Nicholas Hammond.
Among the monuments found within the tumulus were three tombs. One, called Tomb I, had been looted, but contained a stunning wall painting of the Rape of Persephone, along with fragmentary human remains.
Tomb II remained undisturbed and contained the almost complete cremated remains of a male skeleton in the main chamber and the cremated remains of a female in the antechamber. Grave goods included silver and bronze vessels, gold wreaths, weapons, armor and two gold larnakes.
Tomb III was also found unlooted, with a silver funerary urn that contained the bones of a young male, and a number of silver vessels and ivory reliefs.
Most of the scholarly debate concentrated on the occupants of Tomb II, with experts arguing that the occupants were either Philip II and Cleopatra or Meda, both his wives, or Philip III Arrhidaeus, Alexander's half-brother, who assumed the throne after Alexander's death, with his wife Eurydice.
King Philip II was a powerful fourth-century B.C. military ruler from the Greek kingdom of Macedon who gained control of Greece and the Balkan peninsula through tactful use of warfare, diplomacy, and marriage alliances (the Macedonians practiced polygamy).
His efforts -- he reformed the Macedonian army and proposed the invasion of Persia -- later provided the basis for the achievements of his son and successor Alexander the Great, who went on to conquer most of the known world.
The overlord of an empire stretching from Greece and Egypt eastward across Asia to India, Alexander died in Babylon, now in central Iraq, in June of 323 B.C. — just before his 33rd birthday.
His elusive tomb is one of the great unsolved mysteries of the ancient world.
Analyzed by Antikas' team since 2009, the male and female bones in Philip II's tomb have revealed peculiarities not previously seen or recorded.
"The individual suffered from frontal and maxillary sinusitis that might have been caused by an old facial trauma," Antikas said.
Such trauma could be related to an arrow that hit and blinded Philip II's right eye at the siege of Methone in 354 B.C. The Macedonian king survived and ruled for another 18 years before he was assassinated at the celebration of his daughter's wedding.
The anthropologists found further bone evidence to support the identification with Philip II, who being a warrior, suffered many wounds, as historical accounts testify.
"He had signs of chronic pathology on the visceral surface of several low thoracic ribs, indicating pleuritis," Antikas said.
He noted that the pathology may have been the effect of Philip's trauma when his right clavicle was shattered with a lance in 345 or 344 B.C.
Degenerative lesions and markers pointed to a middle-aged man who rode a horse frequently.
Examination of the bones revealed a fully-fleshed cremation, further disproving the theory that the remains belong to Philip III Arrhidaeus, who was buried, exhumed, cremated and finally reburied.
"Features such as cracking, color, warping, twisting seen on the bones indicate pyre-induced morphological alterations," Antikas said.
"A typical example is the 90-degree twisting of the left parietal bone of the man's cranium. This would never happen, if the skull were 'dry', coming from an ossuary," he added.
Additional composite material was also found on the bones. Antikas's team found traces of royal purple, huntite, textile, beeswax and clay belonging to an elaborately made object.
"It was placed on top of the bones after they were cleaned, wrapped and placed in the gold larnax. If they had been burned in the pyre, they would have dissappeared, as its temperature exceeded 800 degrees Celsius at times," Antikas said.
According to the researchers, further evidence for the dead being Philip II is the identity of the female buried in the antechamber, who died at 30-34.
"Her age was determined by examining a pelvis bone fragment not seen or identified by previous researchers," Antikas said.
The finding proved extremely important in the complex identification process.
"Basically her age excludes every other wife-concubine of Philip II and indirectly Arrhidaeus, whose wife was under 25," he said.
Morphological alterations in the bones indicate she was cremated just after her death, just like the deceased in the chamber, while equestrian activity indicators suggest she also rode for a long time.
A fracture in the upper end of her left leg caused shortening, atrophy, "and most probably disfiguration," according to Antikas.
"This leads to the conclusion that the pair of mismatched greaves -- the left is shorter -- the Scynthian gorytus and weaponry found in the antechamber belonged to her," he said.
The finding reinforces the assumption made by Hammond as early as 1978 that the spears, arrows, quiver and greaves belonged to a warrior queen in Philip's royal household. Among the candidates proposed by Hammond were Meda, Cynna (the offspring of Philip and Audata, an Illyrian warrior princess) and an unknown daughter of the Scythian king Ateas, defeated by Philip in 339 B.C.
The Scythian theory also strengthens Philip II's identification.
"No Macedonian King other than Philip is known to have had 'relations' with a Scythian," Antikas said.
According to Adrienne Mayor, a research scholar at Stanford University's Departments of Classics and History of Science, the new bioarchaeological analysis of the bones in Tomb II "is a truly exciting discovery, confirming without a doubt that the weapons and mismatched greaves belonged to a horsewoman-archer close to Philip II."
The author of "The Amazons: Lives and Legends of Warrior Women across the Ancient World," Mayor, however, cautions about the Scynthian princess hypothesis.
"Hammond speculated that Ateas might have sent a daughter to Philip during their negotiations. But their dealings were hostile, not friendly, ending in war and the defeat of Ateas in 339 B.C.," Mayor told Discovery News.
"Moreover, as Hammond acknowledged, there is no mention of a daughter of Ateas in any ancient sources that describe Philip's interactions with Ateas or list the names of his wives," she added.
Mayor proposes another possibility -- that the mystery woman could have been a wife selected by Philip from the 20,000 Scythian women he took as prisoners after the defeat of Ateas. The sources report that these women and their horses all escaped when another Scythian tribe attacked Philip's army on its way back to Macedonia.
"Perhaps one of these women, traveling with Philip's entourage, did not escape and remained in the royal house for three years until his death in 336 B.C. When the king was assassinated, a captive Scythian bride from Ateas' coalition may well have felt compelled to commit suicide," Mayor said.
On another finding, Antikas' team shed new light on the remains in Tomb I. His team found in an old storage place with wood cases containing plastics bags filled with never-studied bones from the tomb, which was thought to contain the remains of a male, a female and an infant. This led some scholars to believe Tomb I contained the remains of Philip, his wife Cleopatra, and their few-week-old child.
Read more at Discovery News
Why are people so scared?
Death from any disease is frightening, but some deaths are worse than others. The gory characteristics of Ebola infection are scary — including not only fever but vomiting, diarrhea and bleeding. Combine that with a high fatality rate and no cure or vaccine — it’s a truly terrifying disease.
The Psychology of the Panic
The invisibility of the threat is psychologically frightening and unsettling. Most of the threats we might face in our everyday lives are clear and recognizable: a car careening towards us on a freeway, a charging dog or an angry person with a gun on the street. We instantly recognize what the threat is, and have some idea of how we might avoid or minimize it.
But the Ebola virus is invisible to the naked eye. It can’t be seen, smelled, tasted, heard or detected by the average person. We don’t know who might have it, or even if we have it (since the initial symptoms mimic the flu) unless confirmed by a doctor. It’s an invisible, silent killer, and the threat could come from anywhere.
Though you may not know anyone who has been to West Africa in the past month, you probably know someone who knows someone who has. Because of the widespread uncertainty, misinformation and false rumors about Ebola, people are confused and frightened.
There is also of course a strong fear of the unknown, and the tendency to overestimate its risks. Most Americans today have lost their fear of serious infectious diseases such as polio, mumps, measles, smallpox, tuberculosis and influenza.
Smallpox killed over a half billion people between 1880 and 1980, the year it was finally eradicated, and it’s rarely discussed today. Even diseases that ravaged the world in the Middle Ages are still with us, though rarely mentioned. The bubonic plague, for example, which once killed about a third of Europe, is still reported in a few places including New Mexico, which saw three cases in 2013.
To put the threat in perspective, on average the flu kills between 4,000 and 50,000 people in the United States alone, depending on the season. So far only one person has died from Ebola, and he contracted it in Liberia. People underestimate the risks of flu because it’s a common and well-known disease. People overestimate the risks of Ebola because it’s an uncommon and poorly-understood disease.
Social and Cultural Fears
There is a social element as well, an underlying element of xenophobia in many of the fears. Fears often reflect both personal and social anxieties. Ebola began in Africa and many people feel it should stay there. For decades the fact that it remained on foreign shores was a psychological comfort. Now the disease has arrived on our continent from Africa.
In their book “The Global Grapevine: Why Rumors of Terrorism, Immigration and Trade Matter,” folklorists Gary Alan Fine and Bill Ellis note that Americans have often associated disease with foreigners:
“Migrants to the United States have (long) been described as a virus that sapped a nation’s strength. Concern was perhaps more symbolically expressed than practically resolved when, in the past, immigrants were given medical exams or quarantined in isolated, ‘sterile’ places like Ellis Island, not yet ready to be incorporated within the nation. Today, these procedures are no longer employed, but we brood about the unchecked transmission of swine flu, bird flu, AIDS or even the Ebola virus by means of foreigners entering our country. With increased international air travel, such transmission is all too plausible.”
The entertainment media also may contribute to the public’s concerns. In a bit of unfortunate timing, the film “Dawn of the Planet of the Apes” — which opened as the most recent Ebola outbreak began and is still screening today — provides a terrifying depiction of a deadly virus spread across the globe by infected travelers. Though the film is clearly fictional, it’s another reminder that deadly viruses may only be an airplane ride away.
Another part of the reason for the public’s fear is a concern, not entirely unfounded, that the Centers for Disease Control and Prevention (CDC) are not fully prepared to deal with this epidemic. While CDC officials appear in the news media daily reassuring the public that they have everything under control, it’s clear that serious missteps occurred in how Duncan’s case was handled.
As CNN reported, “‘A travel history was taken, but it wasn’t communicated to the people who were making the decision. It was a mistake. They dropped the ball,’ said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.”
Many Americans don’t fully trust the government to keep them safe, and that sentiment is not surprising. After all, federal regulators spectacularly failed to prevent the Wall Street collapse, costing many Americans their life savings and plunging the economy into a recession; the government’s reactions to devastating natural disasters such as Hurricane Katrina in 2005 were widely seen as inadequate; and so on.
Given the government’s high-profile failures to help and protect its citizens, it’s not surprising that many Americans are skeptical regarding a newly-arrived, deadly, contagious disease.
Read more at Discovery News
|Ladies and gentlemen, the incredible comb jelly, which considers every day a rave. Unce unce unce.|
These critters, some 150 described species and another 40 or 50 still awaiting names, locomote by beating rows of tiny hairlike structures called cilia. When white light hits them from, say, a submersible’s beam, the cilia break it into its wavelength colors, producing that hypnotic shimmering rainbow. But don’t be fooled by their beauty: Comb jellies—known scientifically as ctenophores (pronounced TEN-oh-fores)—are formidable predators with ultra-fast strikes, hoovering up all manner of zooplankton like copepods and other tiny crustaceans and digesting them alive.
Strangely, though, that laser show is probably a happy accident that only really kicks off when we hit them with high-powered electric light, according to Steve Haddock of the Monterey Bay Aquarium Research Institute (MBARI). “In the wild it probably doesn’t happen, or hardly happens at all,” he said. “And I would think it doesn’t actually have an ecological meaning. It’s kind of a side effect of us bringing them up and shining white lights on them.” Even with comb jellies that tend to live closer to the surface, the effect seems negligible until you hit them with artificial light.
|A ridiculously beautiful shot of a sea gooseberry and its sticky tentacles. If you were a tiny crustacean, this would be the last thing you saw. Lucky, this photographer was not a tiny crustacean.|
As soon as the jellyfish hits the tentacles of the centimeter-long comb jelly, it’s yanked in with astonishing speed. “I was watching one under the microscope one time and I totally jumped in my seat because it was so fast,” said Haddock. “I kind of didn’t expect it to happen. It just engulfed it.” Yet for all their speed, they’re incredibly fragile—pick one up and it’ll essentially melt. Accordingly, Haddock’s colleagues at the world-famous Monterey Bay Aquarium keep them in circular “kreisel” tanks that push water down their sides to create a gyre that keeps the comb jellies suspended in the center.
|The bloodybelly comb jelly, so named because it drinks a lot of bloody Mary’s.|
“I use the analogy of spiders,” he added. “Because spiders can have a sticky web, they can leap out and ambush things, they can make little lasso webs. And ctenophores have similar range of different feeding modes, depending on the species.”
Such a diversity of lifestyles is all the more impressive when you consider comb jellies have a nervous system, but not a brain. Interestingly, earlier this year scientists found the creatures build their neurons unlike any other critter, which they claim could shake up our understanding of the tree of life. The evolutionary history of the comb jelly, though, has long been and continues to be a subject of much debate.
“They have sensors for sensing light and up and down and touch and taste, things like that,” said Haddock. “But the integration is not done by a CPU. It’s basically done by this sort of network of nerves that are connected in a relatively simple pattern.”
With this system, a comb jelly can build what are known as stereotyped behaviors, for instance knowing instinctively to start rotating once prey hits its tentacles in order to bring the quarry up into the mouth. It’s a bit like being on autopilot, only its simplicity is the exact opposite of the complex systems you’d find in jets or the blow-up doll in Airplane.
Quite brilliantly, to deal with this problem many deep-sea varieties of comb jelly have evolved red guts (see photo at right that looks pretty much exactly like the Punisher symbol) or entirely red bodies. Red light has the least amount of energy in the visible spectrum, and therefore doesn’t penetrate as far down in the water column as blue, which has the most energy. A red comb jelly is red because it absorbs all other colors but red, so it will appear black in the depths, where there’s no red light. It’s a remarkable adaptation for an incredibly fragile creature that would do well to avoid being seen.
Read more at Wired Science
Oct 9, 2014
The map provides information about temperatures at different layers of the world's atmosphere and traces the amount and distribution of water vapor on the planet. The findings have ramifications for the understanding of atmospheric dynamics and the formation of giant planets like Jupiter.
"These measurements have opened the door for a new kind of comparative planetology," said team leader Jacob Bean of the University of Chicago.
"Our observations are the first of their kind in terms of providing a two-dimensional map of the planet's thermal structure that can be used to constrain atmospheric circulation and dynamical models for hot exoplanets," said team member Kevin Stevenson of the University of Chicago.
The Hubble observations show that the planet, called WASP-43b, is no place to call home. It's a world of extremes, where seething winds howl at the speed of sound from a 3,000-degree-Fahrenheit day side that is hot enough to melt steel to a pitch-black night side that sees temperatures plunge below a relatively cool 1,000 degrees Fahrenheit.
As a hot ball of predominantly hydrogen gas, there are no surface features on the planet, such as oceans or continents that can be used to track its rotation. Only the severe temperature difference between the day and night sides can be used by a remote observer to mark the passage of a day on this world.
WASP-43b is located 260 light-years away and was first discovered in 2011. WASP-43b is too distant to be photographed, but because its orbit is observed edge-on to Earth, astronomers detected it by observing regular dips in the light of its parent star as the planet passes in front of it.
The planet is about the same size as Jupiter, but is nearly twice as massive. The planet is so close to its orange dwarf host star that it completes an orbit in just 19 hours. The planet is also gravitationally locked so that it keeps one hemisphere facing the star, just as our moon keeps one face toward Earth.
The scientists combined two previous methods of analyzing exoplanets and put them together in one for the first time to study the atmosphere of WASP-43b. Spectroscopy allowed them to determine the water abundance and temperature structure of the atmosphere. By observing the planet's rotation, the astronomers were also able to measure the water abundances and temperatures at different longitudes.
Because there's no planet with these tortured conditions in our solar system, characterizing the atmosphere of such a bizarre world provides a unique laboratory for better understanding planet formation and planetary physics. "The planet is so hot that all the water in its atmosphere is vaporized, rather than condensed into icy clouds like on Jupiter," said team member Laura Kreidberg of the University of Chicago.
"Water is thought to play an important role in the formation of giant planets, since comet-like bodies bombard young planets, delivering most of the water and other molecules that we can observe," said Jonathan Fortney, a member of the team from the University of California, Santa Cruz.
However, the water abundances in the giant planets of our solar system are poorly known because water is locked away as ice that has precipitated out of their upper atmospheres. But on "hot Jupiters" -- that is, large planets like Jupiter that have high surface temperatures because they orbit very close to their stars -- water is in a vapor that can be readily traced. Kreidberg also emphasized that the team didn't simply detect water in the atmosphere of WASP-43b, but also precisely measured how much of it there is and how it is distributed with longitude.
In order to understand how giant planets form, astronomers want to know how enriched they are in different elements. The team found that WASP-43b has about the same amount of water as we would expect for an object with the same chemical composition as the Sun. Kreidberg said that this tells something fundamental about how the planet formed.
Read more at Science Daily
The most prominent odors released by beer are produced by common brewer’s yeast, which evolved the aroma to attract fruit flies. The flies, in turn, benefit yeast by dispersing its cells into the environment.
“Two seemingly unrelated species, yeasts and flies, have developed an intricate symbiosis based on smell,” researcher Kevin Verstrepen of KU Leuven and VIB in Belgium said in a press release. “The flies can feed on the yeasts, and the yeasts benefit from the movement of the flies.”
A paper on the unlikely duo — beer and flies — is published in the latest issue of Cell Reports.
Verstrepen had a light bulb moment 15 years ago while studying how yeast cells contribute to the flavor of both beer and wine.
He discovered that yeast cells produce several pleasant and appetizing aroma compounds similar to those produced by ripening fruits. Like fruit, the yeast uses these tempting smells to lure in beneficial others. One yeast gene in particular, alcohol acetyl transferase (ATF1), was responsible for most of the volatile chemicals.
Verstrepen recalled, “When returning to the lab after a weekend, I found that a flask with a smelly yeast culture was infested by fruit flies that had escaped from a neighboring genetics lab, whereas another flask that contained a mutant yeast strain in which the aroma gene was deleted did not contain any flies.”
The years passed, but he never forgot that moment.
For the recent study, he teamed up with fruit fly neurobiologists Emre Yaksi and Bassem Hassan. The researchers used a combination of molecular biology, neurobiology and behavioral tests to show that loss of ATF1 changes the response of the fruit fly brain to a whiff of yeast.
As predicted from the earlier work, mutant yeast cells were a turnoff to the flies. This was bad for the yeast too, since the altered yeast wasn’t dispersed much by the flies.
Read more at Discovery News
Researchers analyzed more than 9,000 violins, violas, cellos and double basses, and found that the shape of violins depended on the makers' family background, country of origin, the time period in which it was constructed, and how precisely the violins imitated the greats, such as the stringed instruments expertly crafted by Antonio Stradivari.
The first violins were made in Italy in the 16th century. Stradivari, one of history's most respected violin makers, lived in Cremona, in northern Italy, from 1644 to 1737. He crafted roughly 1,000 violins, including about 650 that have survived to this day.
In fact, the study found that the shape of modern violins has been disproportionately influenced by the work of Stradivari, said study researcher Daniel Chitwood, a scientist at the Donald Danforth Plant Science Center in St. Louis.
"It's so well documented that there are violin makers who openly said they were copying Stradivari because his violin shapes were more desirable," Chitwood said.
Chitwood isn't a master violin maker; he's a plant researcher who studies developmental genetics but also plays viola in his spare time. He typically studies how plant genetics relate to the shapes of leaves.
In the new study, he used similar techniques to examine how the "traits" of violins, or their shapes, changed over time. "Really, violins are just a trait of human beings, just as plants have a trait," Chitwood told Live Science.
Some imitations are so exact that, in a separate study pitting new violins against the ones of the old masters, expert violin soloists could not distinguish between old and new violins. The soloists also preferred the new violins to the old ones, surprising musicians everywhere, the study, published in the journal the Proceedings of the National Academy of Sciences, found.
" are exceptional violins, but they're not always the best violin," Chitwood said.
When and where a violin was made also factored heavily into the instrument's shape. "These people couldn't help but be born in Cremona, or Paris or London," Chitwood said. "The instruments that they produced were shaped by where they were in history and where they were at."
Violin making also tended to be a family business passed down through the generations, so "human relatedness was also contributing to the different violin shapes throughout history," Chitwood added. For instance, the brothers Nicolò and Gennaro Gagliano, who lived in Italy during the 1700s, made similarly shaped violins.
To assess the evolution of violin shapes, Chitwood relied on images from online sales of rare and valuable violins. By analyzing the outlines of the instruments, Chitwood found four main "blueprints" influenced by master instrument-making families, including Stradivari, the Italian Giovanni Paolo Maggini (1580-1630), the Italian Amati family and the Austrian Jacob Stainer (1617-1683).
While examining the outlines of violins, Chitwood also found that using his analysis, the shape of a viola is indistinguishable from that of a violin about 63 percent of the time. A viola player himself, Chitwood said the instrument should probably be larger to accommodate its deeper range but that instrument makers decided to limit its size so that it could be played under the chin, like a violin, instead of between the legs, like a cello.
"We wrongly decided that we're going to put them under our chin," Chitwood said. "But the real solution is that we should be playing violas between our knees."
Shape and sound
"This study looks at evolutionary patterns in that outline over the centuries," said Jim Woodhouse, a professor of engineering at the University of Cambridge in the United Kingdom, who was not involved in the study. "It reveals some fairly clear trends, and also clear clusters of related shapes."
The arching patterns and thickness of the wood used to make a violin's plates, as well as the plates' wood properties, are vital to the instrument's acoustics. In contrast, the shape of a violin doesn't have a strong influence over its sound, which means crafters can experiment with how they construct the body of the instrument.
Read more at Discovery News
The cave art, reported in the journal Nature, also includes multiple human hand stencils and dates to around 40,000 years ago during the Ice Age. The oldest known rock art, found in Europe, would have been created around the same time.
“It was previously thought that Western Europe was the centerpiece of a ‘symbolic explosion’ in early human artistic activity, such as cave painting and other forms of image-making, including figurative art, around 40,000 years ago,” lead author Maxime Aubert of Griffith University told Discovery News.
“However,” he added, “our findings show that cave art was made at opposite ends of the Pleistocene Eurasian world at about the same time, suggesting these practices have deeper origins, perhaps in Africa before our species left this continent and spread across the globe.”
The prehistoric images, from limestone caves near Maros in southern Sulawesi, have been known for a while, but researchers were uncertain about their age. Co-author Adam Brumm, also from Griffith University, noticed that small stalactite-like growths, called "cave popcorn,"’ had formed over the art.
The growths turned out to be an ideal medium for uranium-series dating. The dating only provides a minimum, so the cave art may even be much older than 40,000 years ago.
Aubert explained that the hand stencils were made by blowing, spraying or spitting a mouthful of liquid ochre pigment on the cave wall, leaving behind the hand shapes.
“The hands seem to belong to a wide range of ages, and possibly sexes, although this is difficult to determine,” Aubert said. “Certainly there are hands of both adults and children.”
“What is most interesting about the early Sulawesian and European animal painting is not so much what the prehistoric artists depicted, but what they didn’t depict -- meaning, in both regions the set of animals present in the local environment was much wider than the set of animals represented in the art,” Brumm told Discovery News.
He continued, “What these hunter-gatherers overwhelmingly depicted, both in Europe, and Sulawesi, were large, and often dangerous, mammal species that possibly played major roles in the belief systems of these people. In that sense, therefore, differences in the actual techniques and methods used to produce the art in these widely separated regions are not as important as the common themes that drove these groups of artists to very selectively represent the worlds they inhabited.”
Aubert, Brumm and their colleagues believe that Homo sapiens created the art, but our species wasn't the only hominid present in Indonesia at the time.
Wil Roebroeks, author of an accompanying piece in Nature, told Discovery News that “the ‘modern human’ makers of the Sulawesi/Maros rock art probably differed slightly from the ‘modern humans’ in western Europe, in the sense that while both populations were overall of African descent with some Neanderthal admixture, a small part of the Sulawesi’s genetic ancestry probably also traced back to the famous Denisovans (another early hominid).”
Roebroeks, of Leiden University, added that just south of Sulawesi at the time, Homo floresiensis, aka the “Hobbit Human,” was still living.
Read more at Discovery News
Oct 8, 2014
Impossibly bright dead star: X-ray source in the Cigar Galaxy is the first ultraluminous pulsar ever detected
"This compact little stellar remnant is a real powerhouse. We've never seen anything quite like it," says Harrison, NuSTAR's principal investigator and the Benjamin M. Rosen Professor of Physics at Caltech. "We all thought an object with that much energy had to be a black hole."
Dom Walton, a postdoctoral scholar at Caltech who works with NuSTAR data, says that with its extreme energy, this pulsar takes the top prize in the weirdness category. Pulsars are typically between one and two times the mass of the sun. This new pulsar presumably falls in that same range but shines about 100 times brighter than theory suggests something of its mass should be able to.
"We've never seen a pulsar even close to being this bright," Walton says. "Honestly, we don't know how this happens, and theorists will be chewing on it for a long time." Besides being weird, the finding will help scientists better understand a class of very bright X-ray sources, called ultraluminous X-ray sources (ULXs).
Harrison, Walton, and their colleagues describe NuSTAR's detection of this first ultraluminous pulsar in a paper that appears in the current issue of Nature.
"This was certainly an unexpected discovery," says Harrison. "In fact, we were looking for something else entirely when we found this."
Earlier this year, astronomers in London detected a spectacular, once-in-a-century supernova (dubbed SN2014J) in a relatively nearby galaxy known as Messier 82 (M82), or the Cigar Galaxy, 12 million light-years away. Because of the rarity of that event, telescopes around the world and in space adjusted their gaze to study the aftermath of the explosion in detail.
This animation shows a neutron star -- the core of a star that exploded in a massive supernova. This particular neutron star is known as a pulsar because it sends out rotating beams of X-rays that sweep past Earth like lighthouse beacons. (Credit: NASA/JPL-Caltech)
Besides the supernova, M82 harbors a number of other ULXs. When Matteo Bachetti of the Université de Toulouse in France, the lead author of this new paper, took a closer look at these ULXs in NuSTAR's data, he discovered that something in the galaxy was pulsing, or flashing light.
"That was a big surprise," Harrison says. "For decades everybody has thought these ultraluminous X-ray sources had to be black holes. But black holes don't have a way to create this pulsing."
But pulsars do. They are like giant magnets that emit radiation from their magnetic poles. As they rotate, an outside observer with an X-ray telescope, situated at the right angle, would see flashes of powerful light as the beam swept periodically across the observer's field of view, like a lighthouse beacon.
The reason most astronomers had assumed black holes were powering ULXs is that these X-ray sources are so incredibly bright. Black holes can be anywhere from 10 to billions of times the mass of the sun, making their gravitational tug much stronger than that of a pulsar. As matter falls onto the black hole the gravitational energy turns it to heat, which creates X-ray light. The bigger the black hole, the more energy there is to make the object shine.
Surprised to see the flashes coming from M82, the NuSTAR team checked and rechecked the data. The flashes were really there, with a pulse showing up every 1.37 seconds.
The next step was to figure out which X-ray source was producing the flashes. Walton and several other Caltech researchers analyzed the data from NuSTAR and a second NASA X-ray telescope, Chandra, to rule out about 25 different X-ray sources, finally settling on a ULX known as M82X-2 as the source of the flashes.
With the pulsar and its location within M82 identified, there are still many questions left to answer. It is many times higher than the Eddington limit, a basic physics guideline that sets an upper limit on the brightness that an object of a given mass should be able to achieve.
"This is the most extreme violation of that limit that we've ever seen," says Walton. "We have known that things can go above that by a small amount, but this blows that limit away."
Read more at Science Daily
The black hole -- known as P13 -- lies on the outskirts of the galaxy NGC7793 about 12 million light years from Earth and is ingesting a weight equivalent to 100 billion billion hot dogs every minute.
The discovery was published today in the journal Nature.
International Centre for Radio Astronomy Research astronomer Dr Roberto Soria, who is based at ICRAR's Curtin University node, said that as gas falls towards a black hole it gets very hot and bright.
He said scientists first noticed P13 because it was a lot more luminous than other black holes, but it was initially assumed that it was simply bigger.
"It was generally believed the maximum speed at which a black hole could swallow gas and produce light was tightly determined by its size," Dr Soria said.
"So it made sense to assume that P13 was bigger than the ordinary, less bright black holes we see in our own galaxy, the Milky Way."
When Dr Soria and his colleagues from the University of Strasbourg measured the mass of P13 they found it was actually on the small side, despite being at least a million times brighter than the Sun. It was only then that they realised just how much material it was consuming.
"There's not really a strict limit like we thought, black holes can actually consume more gas and produce more light," Dr Soria said.
Dr Soria said P13 rotates around a supergiant 'donor' star 20 times heavier than our own Sun.
He said the scientists saw that one side of the donor star was always brighter than the other because it was illuminated by X-rays coming from near the black hole, so the star appeared brighter or fainter as it went around P13.
"This allowed us to measure the time it takes for the black hole and the donor star to rotate around each other, which is 64 days, and to model the velocity of the two objects and the shape of the orbit," Dr Soria said.
"From this, we worked out that the black hole must be less than 15 times the mass of our Sun."
Dr Soria compared P13 to small Japanese eating champion Takeru Kobayashi.
"As hotdog-eating legend Takeru Kobayashi famously showed us, size does not always matter in the world of competitive eating and even small black holes can sometimes eat gas at an exceptional rate," he said.
Read more at Science Daily
Orcas that were socialized with bottlenose dolphins started making similar sounds as the dolphins, with more clicks and fewer longer calls, according to a study by University of San Diego graduate student Whitney Musser and Hubbs-SeaWorld Research Institute senior research scientist Dr. Ann Bowles published in The Journal of the Acoustical Society of America.
Does this mean that killer whales have language, in the way that we understand it? It's known that orcas communicate in so-called dialects, complex vocalizations comprised of clicks, whistles and pulsed calls. And whales that live together in the same pod use the same sounds to communicate, according to a press release.
"There's been an idea for a long time that killer whales learn their dialect, but it isn't enough to say they all have different dialects so therefore they learn. There needs to be some experimental proof so you can say how well they learn and what context promotes learning," Bowles said.
Bats, some bird species and cetaceans, which includes whales and dolphins, have all exhibited vocal learning. Scientists know quite a lot about songbirds, since their small size makes it easy to study their brains and neural pathways, the press release said.
But, understandably, the sheer size of ceteceans makes it hard to study how they vocalize and learn. And since many ceteceans are under threat by habitat loss, global warming and human activities like commercial fishing, it's more important than ever to find out more about them, according to the release.
"It's important to understand how they acquire [their vocalization patterns], and lifelong, to what degree they can change it, because there are a number of different populations on the decline right now," Bowles said. "And where killer whales go, we can expect other small whale species to go -- it's a broader question."
From Discovery News
Dinosaurs recovered from northern South America are rare so "Thief of Tachira" (Tachiraptor admirabilis) is all the more noteworthy. It's only the second known dinosaur from what is now Venezuela.
The new dino, described in the journal Royal Society Open Science, measured just 6.6 feet long, but it had a ravenous craving for meat.
"Tachiraptor probably preyed upon any smaller animal he could catch," lead author Max Langer explained to Discovery News.
Langer, a paleontologist at the Universidade de Sao Paulo, and his colleagues discovered Tachiraptor's remains in the Venezuelan state of Tachira. The dinosaur represents both a new genus and species.
The remains, based on radiometric dating of rocks at the site, date to 200 million years ago. This corresponds to the earliest phase of the Jurassic Period.
The date and location of the fossils help to explain how carnivorous dinosaurs spread around the world after the end of the Triassic mass extinction. That devastating event wiped out an estimated 84 percent of all species, including many dinosaur groups.
The ancestors of "Thief of Tachira," however, were clearly a hearty lot that survived the onslaught, possibly triggered by volcanic eruptions, extreme temperatures and falling sea levels. Helping the spread of dinosaurs after the extinction event was the fact that most of the continents at the time were joined together to form the supercontinent Pangaea.
Langer said that "an equatorial belt including southern North America, northern South America and northern Africa were bordered to the north and south by extensive deserts." The more hospitable belt "played a pivotal role in the radiation of the different dinosaur groups."
Langer explained that within the belt region conditions were more humid and tropical. He and his colleagues believe the area where Thief of Tachira was found was then forested, with rivers nearby. In short, it would have been a quite comfortable place for a dinosaur to live.
Life would not have been quite so pleasant for Venezuela's other known dinosaur, Laquintasaura. Langer suspects that Tachiraptor spent a lot of time hunting this smaller plant-munching dinosaur, which was about half of the predator's size.
Paul Barrett, a Natural History Museum paleontologist who led the discovery of Laquintasaura, told Discovery News that Laquintasaura probably lived in herds, offering some protection from bloodthirsty Thief of Tachira.
Barrett said that despite the end of the Triassic mass extinction, "dinosaurs bounced back quickly after this event. It is fascinating and unexpected to see they lived in herds, something we have little evidence so far in dinosaurs from this time."
It is uncertain whether or not the new carnivorous dinosaur lived solo or in a herd. Predators even today tend not to live in herds.
As for why so few dinosaurs have yet to be discovered from Venezuela and northern South America in general, Langer had a simple and short answer: few paleontologists are conducting research in the area.
Read more at Discovery News
|Alfred Lawson, second from left, and crew, Sep. 16, 1919 in Mineola, Long Island.|
Writing in the third person, per his M.O., Lawson claimed “his mind responds to every question, and the problems that stagger the so-called wise men are as kindergarten stuff to him.” And writing through the pseudonym Cy Q. Faunce, perhaps betraying a hint of modesty, or at least tact: “To try to write a sketch of the life and works of Alfred W. Lawson in a few pages is like trying to restrict space itself. It cannot be done.”
According to Martin Gardner in his book Fads and Fallacies in the Name of Science, the Life That Cannot Be Sketched began in London in 1869. (“The birth of Lawson was the most momentous occurrence since the birth of mankind,” Cy Q. Faunce once wrote.) Lawson’s family moved just after this miraculous event to Canada before settling in Detroit, though Lawson eventually ran away from home and hopped freight trains around the States. At 19 he began a nearly two-decade career as a pro baseball pitcher, though he eventually grew disillusioned with all the money, tobacco, and liquor. And, apparently, fun.
In 1908 he began pursuing another passion: aviation. After editing a few industry magazines, he designed and built training planes for the Army, and according to Gardner claimed to have been the first to propose the idea of the aircraft carrier. In 1919, though, he embarked on the quest that would become his legacy—inventing the passenger airliner … well, kinda. His first airliner could carry 18 passengers, while two competing planes in Europe, which took to the skies just months before Lawson’s, could carry only four—hardly what we could consider commercially feasible, but nevertheless airliners of a sort. Regardless, in the following years he brought innovation after innovation to commercial flight, and built a rather profitable company to boot. But when a new model of his airliner crashed in 1921, his financial backers fled, and Lawson Airlines collapsed.
|One of Lawson Airline’s formidable planes. One of those guys may be Lawson, but it’s hard to tell because they didn’t have megapixels and autofocus and whatnot back then.|
Education is the science of knowing TRUTH.
Miseducation is the art of absorbing FALSITY.
TRUTH is that which is, not that which ain’t.
FALSITY is that which ain’t, not that what is.
Hard to argue with that. What’s easy to argue with is pretty much the entirety of Lawsonomy’s other teachings, which were hard for students to ignore on account of the university banning all books not written by Lawson himself, including at one point a work on the rules of basketball. You know, just to be safe.
Earth Has an Anus, and Other Teachings of Lawsonomy
First of all, Lawsonomy teaches that energy doesn’t exist. Like, at all. What Lawson proposed, according to Gardner, is that we instead have an eternal battle between substances of varying densities. Materials of heavy density move toward those with less density, creating “suction” and “pressure.” So, we can see because our eyes draw light in by suction (in reality, light travels just fine on its own, thank you very much), while gravity is the “pull of the Earth’s suction” (it’s actually a distortion of space-time). This theory was derived from Lawson’s groundbreaking observation, at age 4, that blowing on dust pushed it away, while inhaling brought it closer.
|Lawson was a handsome man, which might help explain why people would buy into his baloney.|
As for our bodies, suction and pressure are at work there too, Lawson claimed. Air and food are sucked in, while pressure ejects waste. In fact, the human body is simply aswirl with suction and pressure, but when all that ceases, you perish. Sex is also all suction and pressure: women are the former and men the latter. Plus, the “attraction of one sex for the other,” writes Lawson, “is merely the attraction of Suction for Pressure.” This, conveniently enough, also solves the “mystery” of magnetism. Should a magnet have more female particles than male, “it will have the power of suction,” while a magnet with more male particles produces pressure to “push matter away from it.” (Magnetism, in fact, comes down to electrons all aligning their magnetic fields within atoms, which themselves must align inside a metal like iron to make it magnetic.)
Now, when it comes to the brain, that marvelously complex structure, simple suction and pressure won’t suffice. Here, according to Lawsonomy, two tiny creatures are locked in perpetual conflict: the Menorgs, or mental organizers, and the Disorgs, the disorganizers—“microscopic vermin,” claims Lawson, “that infect the cells of the mental system and destroy the mental instruments constructed and operated by the Menorgs.” He adds in rather poetic terms that “a Menorg will sacrifice himself for the benefit of the body, but a Disorg will sacrifice the body for the benefit of himself.”
Read more at Wired Science
Oct 7, 2014
"This underestimation is a result of poor sampling prior to the last decade and limitations of the analysis methods that conservatively estimated temperature changes in data-sparse regions," said oceanographer Paul Durack, from Lawrence Livermore National Laboratory, and the lead author of one of the papers.
The findings are important because oceans absorb about 90 percent of the planet's excess heat, and the Southern Hemisphere accounts for 60 percent of the world's oceans. The latest data suggests that the planet is warming faster than previously thought.
"By using satellite data, along with a large suite of climate model simulations, our results suggest that global ocean warming has been underestimated by 24 to 58 percent," Durack said in a press release. "The conclusion that warming has been underestimated agrees with previous studies, however it's the first time that scientists have tried to estimate how much heat we've missed."
In 2004, researchers began collecting more accurate measurements by deploying 3,600 robotic measuring devices, called Argo floats, which relayed information on the heat stored in the upper layers of the world's ocean currents.
Determining how fast the oceans are warming relates directly to how fast the atmosphere is warming and how much sea levels will rise, the researchers wrote.
Read more at Discovery News
In a new round of funding announced on Monday, NASA is allocating $50 million to 7 astrobiology research groups in the US to tackle these questions.
The grants will cover 5 years of study and will average $8 million per research group.
“With the Curiosity rover characterizing the potential habitability of Mars, the Kepler mission discovering new planets outside our solar system, and Mars 2020 on the horizon, these research teams will provide the critical interdisciplinary expertise to help interpret data from these missions and future astrobiology-focused missions,” said Jim Green, director, Planetary Science Division, at NASA Headquarters, Washington D.C.
The astrobiology teams are based at 3 NASA institutions (Jet Propulsion Laboratory in Pasadena, Calif., Goddard Space Flight Center, Greenbelt, Md. and Ames Research Center, Moffett Field, Calif.), 3 universities (University of Colorado at Boulder, University of California, Riverside and the University of Montana in Missoula) and at The Search for Extraterrestrial Intelligence (SETI) at Mountain View, Calif.
The multidisciplinary teams will tackle everything from evaluating environments on Earth and using them as analogs for extraterrestrial locations, to unraveling the organic chemistry that was likely delivered to early Earth via comet and asteroid impacts. In preparation for NASA’s 2020 Mars rover mission, one of the projects will also involve grasping a better understanding as to how to look for, and even recognize, life on the red planet. Projects delving into extremophiles on Earth and how our planet acquired its oxygen also feature.
“The intellectual scope of astrobiology is vast, from understanding how our planet went from lifeless to living, to understanding how life has adapted to Earth’s harshest environments, to exploring other worlds with the most advanced technologies to search for signs of life,” said Mary Voytek, director, astrobiology program, NASA Headquarters. “The new teams cover that breadth of astrobiology, and by coming together in the NAI (NASA Astrobiology Institute), they will make the connections between disciplines and organizations that stimulate fundamental scientific advances.”
Read more at Discovery News
When Apollo astronauts returned lunar surface samples of rock and regolith (fine, pulverized rocky grains), it was assumed they would be bone dry. After all, the moon has no atmosphere — any water deposited on the surface from impacts would have been long lost to space.
But in recent analysis of the regolith, scientists were surprised to find quantities of water locked in the lunar material.
There are quantities of ice deposits all over the moon’s surface; some large deposits exist in polar craters where sunlight never shines on the crater bottoms. And now we know that even the sun-baked surface and sub-surface has a frozen supply.
According to new research by astrochemists Alice Stephant and François Robert, of Muséum National d’Histoire Naturelle, Paris, the source of the vast majority of the surface water trapped in regolith samples is not from aeons of asteroid and comet impacts — two well known sources of cosmic water ice — it’s the sun. Rather, the water found in lunar regolith is created via chemical reactions with the solar wind.
Their findings have been published in the Proceedings of the National Academy of Sciences.
Through isotopic analysis of deuterium/hydrogen and lithium isotope ratios, the researchers were able to determine that the source of the water did not originate from ancient impacts, but from reactions in and on silicate regolith grains. High-energy protons from the solar wind impact these grains, unlocking oxygen atoms, allowing them to bond with abundant hydrogen atoms, kickstarting the formation of hydroxyl, a tracer for water. Hydroxyl is a simple molecule of one oxygen atom and a hydrogen atom, whereas water has two hydrogen atoms bonded to an oxygen atom.
Read more at Discovery News
White dwarfs form after sun-like stars extinguish the majority of hydrogen fuel in their fusion cores. This causes heavier and heavier elements to fuse, turning the star from a once-quiescent state into a violent, churning red giant. Eventually, through powerful stellar convulsions, the bloated red giant is ripped apart, leaving a small, dense white dwarf in its wake.
A white dwarf’s structure is not maintained by the outward pressure supplied by fusion reactions to counter gravity, like our sun. The quantum pressure supplied by electron degeneracy is what prevents its gravity from causing it to collapse in on itself. This balance between forces creates a very dense stellar object that may have a mass comparable to the sun, but collapsed into a diameter comparable to the Earth. As such, white dwarfs can continue to shine for many billions of years.
When observing white dwarf spectra (i.e. the different wavelengths of light), astronomers have noted that many examples possess atmospheres that are “metal rich.” In astronomy terms this means there are elements trapped in the upper layers of the white dwarf heavier than helium. Depending on the elements present, astronomers have interpreted these spectroscopic signatures as being asteroids or even planets that have survived the death of their sun-like stars, only to later become shredded by the white dwarf’s intense tides. This shredded, dusty material rains down on the white dwarfs, leaving a spectroscopic signature of the ultimate death of planetary systems.
This area of white dwarf study has led to some fascinating observations of star systems that may resemble our solar system after the sun has run out of fuel in a few billion years time and turned into a white dwarf; the planets and asteroids near to our sun’s corpse become ripped apart, enriching our sun’s white dwarf with metals.
In new research accepted for publication in the journal Monthly Notices of the Royal Astronomical Society, astrophysicist Dimitri Veras of the University of Warwick and colleagues have now found a possible mechanism that could be lacing white dwarf atmospheres, not with metals, but with hydrogen.
“Here we explore the possibility that the gradual accretion of exo-Oort cloud comets, which are a rich source of hydrogen, contributes to the apparent increase of trace hydrogen with white dwarf cooling age,” writes Veras.
The build-up of hydrogen in white dwarf atmospheres has been attributed to interstellar hydrogen being collected by white dwarfs as they age, but to account for the quantities being observed, there must be another source, argues Veras.
Surrounding our solar system is hypothesized to be a region of space containing billions of icy bodies — the nuclei of comets. By calculating the trajectory of long-period comets that fall through the solar system, this region — known as the Oort cloud — is thought to extend around 1 light-year from the sun. Intermittently, possibly after a stellar close pass, these cometary nuclei are gravitationally knocked out of the Oort cloud and drop under the influence of the sun’s gravity and careen through the inner solar system, often falling into the sun.
The presence of comets have been detected around other stars before, mainly through the detection of cometary dust around young stars. But Veras’ team suggests that, through numerous computer models of cometary distributions surrounding white dwarf stars, the trace spectroscopic signal of hydrogen in some white dwarf atmospheres is caused by in-falling comets from those stars’ exo-Oort clouds.
Read more at Discovery News
Oct 6, 2014
That's no doubt what a Black Labrador mix thought when he woke up from being euthanized -- twice -- at an animal shelter in Helena Ala.
The 4-year-old lab was christened "Lazarus" by the woman who found him alive the morning after a vet gave him two shots that should have killed him. The first one wasn't enough to stop his heart, apparently.
"When the staff arrived in the morning, to their shock the dog was looking at them. He had even eaten his left over food from the day before. Though scared and wobbly, he was sitting in his cage alive!" Sonya King, of Two By Two Rescue, wrote on the rescue's Facebook page.
The dog had been dropped at the shelter by its owner, who was moving and could no longer care for it, according to an Associated Press report. After a week, he wasn't adopted, so the vet euthanized him -- or, thought he did.
While unusual, Auburn University veterinarian Robert Lofton told AP that the vet could have missed a vein, or perhaps administered an incorrect dose.
Lazarus was shaky after his ordeal, but after some time, he has recovered.
"Lazarus is no longer stumbling and losing his balance. He has a great appetite and is so appreciative to be loved. He responds quickly to his name! Lazarus is the easiest dog I have ever fostered. He has not barked once. He is a perfect gentleman; house & leash trained and sits for a treat. He does not jump on the furniture like the rest of my unruly fur babies. He sits beside me in the mornings as I have quiet time with God. Lazarus' health is perfectly restored and there are no lasting effects. Lazarus was raised from the dead! True Story," King wrote.
From Discovery News
Dubbed by Italian media as “the witch girl,” the skeleton was unearthed at the complex of San Calocero in Albenga on the Ligurian Riviera, by a team of the Pontifical Institute of Christian Archaeology at the Vatican.
The site, a burial ground on which a martyr church dedicated to San Calocero was built around the fifth and sixth centuries A.D., was completely abandoned in 1593.
The prone burial, which has yet to be radiocarbon dated, is thought to date from the late antiquity or the early Middle Ages.
“These rare burials are explained as an act of punishment. What the dead had done was not accepted by the community,” said Stefano Roascio, the excavation director. Like other deviant burials, in which the dead were buried with a brick in the mouth, nailed or staked to the ground, or even decapitated and dismembered, the facedown treatment aimed to humiliate the dead and impede the individual from rising from the grave.
“In particular, the prone burial was linked to the belief that the soul left the body through the mouth. Burying the dead facedown was a way to prevent the impure soul threatening the living,” anthropologist Elena Dellù told Discovery News.
In extreme cases, a facedown burial was used as the ultimate punishment, with the victim horrifically buried alive.
It wasn’t a treatment used on the teenage girl, however.
“The skeleton’s position rules out this possibility,” Dellù said.
Found with her hands placed on the pelvis and straight and parallel legs, the girl showed no apparent signs of a violent death in her bones. However, Dellù noticed porotic hyperostosis on the skull and orbits. These areas of spongy or porous bone tissue are the result of a severe anaemia.
“She could have suffered from an inherited blood disorder such as thalassemia or from hemorrhagic conditions. More simply, it could have been an iron lacking diet,” Dellù said.
Standing just under 5 feet tall, the young girl somehow scared the community -- perhaps it was just her pallor, her possible hematomas and fainting.
Intriguingly, her disrespectful burial was found in a privileged area, just in front of the church.
Read more at Discovery News
The 843-acre park’s soil is home to 167,000 different microbial life forms, according to a study just published in the scientific journal Proceedings of the Royal Society.
“Central Park soils harbored nearly as many distinct soil microbial phylotypes and types of soil communities as we found in biomes across the globe — including arctic, tropical and desert soils,” wrote the researchers. “This integrated cross-domain investigation highlights that the amount and patterning of novel and uncharacterized diversity at a single urban location matches that observed across natural ecosystems spanning multiple biomes and continents.”
“There are all these organisms and we don’t know what they’re doing, we don’t have names for them or anything like that,” Noah Fierer, an associate professor of ecology and evolutionary biology at the University of Colorado who is one of the paper’s authors, told the New York Times.
According to Scientific American, the researchers looked at 596 different soil samples from the park, and compared the microbes from them to 52 other soil samples taken from all over the planet. Amazingly, they found microorganisms that also exist in a wide variety of other environments, ranging from tropical rainforests and prairies to deserts. The only area that didn’t have any microbes in common with Central Park, oddly, was Antarctica.
From Discovery News
But why can't all these people just be tested for Ebola as soon as possible?
Ebola is difficult to diagnose when a person is first infected because the early symptoms, such as fever, are also symptoms of other diseases, such as malaria and typhoid fever.
"The symptoms are extremely nonspecific in the beginning — Ebola looks like almost anything," said Dr. Bruce Hirsch, an infectious-disease specialist at North Shore University Hospital in Manhasset, New York.
Who could have it?
The main question doctors consider is whether the person has been in one of the countries in West Africa experiencing the current Ebola outbreak (Guinea, Sierra Leone or Liberia) within the last 21 days, which is the incubation period of the virus, Hirsch told Live Science. Or, whether that person has been exposed to someone has been one of those places, he added.
Earlier this week, a man in Texas became the first person to be diagnosed with Ebola in the United States, after traveling to Dallas from Liberia. The patient sought medical care but was initially sent home, before being admitted to a hospital in Dallas and testing positive for the virus.
Ebola spreads via contact with the blood or bodily fluids of an infected person, objects contaminated with those fluids or contact with infected animals; it does not spread through the air. Symptoms of the disease include a fever greater than101.5 degrees Fahrenheit (38.6 degrees Celsius), severe headache, muscle pain, diarrhea, vomiting, abdominal pain or unexplained hemorrhage, according to the Centers for Disease Control and Prevention (CDC).
If a person shows these symptoms and has been in an area with Ebola within the past 21 days, they should be put in isolation and tested for Ebola, the CDC says.
Tests for Ebola
A number of tests can be used to diagnose Ebola within a few days of the onset of symptoms, which can detect the virus's genetic material or the presence of antibodies against the pathogen.
The most accurate of these is likely the polymerase chain reaction (PCR) test, a technique that looks for genetic material from the virus and creates enough copies of it that it can be detected, Hirsch said. "PCR is a really definitive test," Hirsch said. It can pick up very small amounts of the virus.
However, this test can be negative during the first three days an infected person has symptoms, said Dr. Sandro Cinti, an infectious-disease specialist at the University of Michigan Hospital System/Ann Arbor VA Health System.
"Somebody could be in the hospital for three to five days before a diagnosis [of Ebola] is confirmed," Cinti told Live Science. "The important thing is keeping the patient isolated until you can get to a diagnosis." Meanwhile, doctors will be running tests to rule out other diseases, such as malaria, which can be detected more quickly than Ebola, he said.
Another test for Ebola looks for antibodies produced by the body's immune system in response to the virus. Known as the antigen-capture enzyme-linked immunosorbent assay (ELISA), this test can take even longer than three days to give a positive result for an infected person, Cinti said. And antibodies can also be detected after a patient recovers, he added.
Once a patient is diagnosed with Ebola, scientists may attempt to isolate the virus — which is a type of filovirus, known for their filamentlike shape — by culturing it with living cells and examine it using electron microscopy. But culturing Ebola is very dangerous, and should only be done in a high-biosafety-level lab, Hirsch said. Culturing the virus is not a practical means of diagnosing infection, but may help researchers understand how the virus infects cells and test possible treatments.
Read more at Discovery News