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Twin Stars Are Closer to Earth Than Thought
An artist’s concept of Z Camelopardalis (Z Cam), a stellar system similar to SS Cygni. The white dwarf, the bright white object within the disk on the left, sucks matter from its more sedate companion star, on the right. The stolen material forms a rotating disk of gas and dust around the white dwarf. Credit: NASA/JPL-Caltech
Imagine if you could see a car’s headlights from more than 20 miles away. Those must be some headlights! It might even throw your whole understanding of headlights into question – how could there be any this bright? But then, you realize that the car wasn’t 20 miles away, but just 2; instantly, things make sense again.
This is how scientists solved an astronomical mystery involving not headlights, but a double star system named SS Cygni. It’s a kind of system known as a dwarf nova, which is made up of a white dwarf star and a red dwarf star orbiting each other. Over the years, astronomers had seen a variety of dwarf nova systems and thought they understood their mechanics: The more massive white dwarf pulls gas off its companion and into a flat disk surrounding the white dwarf. Occasionally (about every 49 days in SS Cygni’s case), the flow of material changes and causes instabilities in this disk, which causes a powerful outburst of energy.
New Bird Flu May Be Able to Spread Between People
Since it was first identified by Chinese authorities two months ago, the new H7N9 bird flu has infected 131 people in eastern China. The virus produces severe pneumonia, with most patients requiring hospitalization, and statistics [pdf] released last week by the WHO indicate that 32 of those infected have died of the virus.
Now a study in ferrets, considered the best model animal of flu transmission in humans, has found that the virus is transmissible via air and direct contact, making it possibly capable of human-to-human transmission as well. Such transmission was seen with the last major bird flu threat, H5N1, but it was limited to small number of cases.
Rise in Whooping Cough Linked to Weak Vaccine
Whooping cough is staging a comeback. According to the CDC, 2012 saw nearly 42,000 pertussis cases—the most since 1955. Many public health officials initially believed the epidemic was due to falling vaccination rates. But a new study published this week in Pediatrics shows that the problem is also due to serious shortcomings of the vaccination itself.
Beginning in the mid-1990s, the U.S. began using a new pertussis vaccine that showed fewer side effects. Instead of injecting killed Bordetella pertussis bacteria to provoke an immune response, the new acellular vaccine only contains certain proteins from the outer layer of the bacterium. The acellular vaccine was less likely to cause fever and pain at the injection site.
Initially, all looked good until scientists began noticing that even properly vaccinated individuals were becoming ill. A closer look at their vaccination histories revealed that many of these people had received the newer, acellular vaccine. Researchers at the Northern California Kaiser Permanente Vaccine Study Center, led by Nicola Field, decided to look at this phenomenon more carefully.
Single Gene Leads to Longer Lifespan Across Species
Mitochondria are the cell’s workhorse, transforming the calories we eat into useable energy. They have also been the subject of lots of scrutiny over longevity, since lifespan is intimately tied up with metabolism. Now a new study reports that mitochondrial malfunction may actually be the key to extending life.
Although loss of mitochondrial function has been associated with increased lifespan in a number of species, the reasons behind this effect have been poorly understood. It’s also been known that low levels of stress within a cell—for instance, running on low energy—can increase an animal’s lifespan. Most of these studies have however been done in flies, worms and yeast. Thus a Swiss research team led by Riekelt Houtkooper decided to examine stress and longevity in mice, as well as the worm C. elegans.
Neanderthal Babies Weaned Early, Fossil Teeth Suggest
“Got milk?”
It’s not just a ubiquitous ad slogan — a primate infant’s access to breast milk has significant consequences for a species’ life cycle. For the first time, researchers have been able to look back 100,000 years to understand how Neanderthal infants might have been nursed and weaned.
According to a study published today in Nature, patterns of barium distribution in the fossilized teeth of a juvenile Neanderthal indicate that the individual began weaning at seven months, comparable to human infants and chimpanzees, but that weaning was completed by the age of 14 months — within the range of human patterns but significantly sooner than chimps.
See Inside a Chrysalis as it Develops Into a Butterfly [Video]
A painted lady chrysalis. Photo by Deanster1983 via Flickr.
Watching a butterfly emerge from its chrysalis is enough to evoke wonder even from the most world-weary of souls. But rarely do we get to see behind the scenes of the pupa’s transformation. Current methods rely on dissection of the chrysalis, or at best, staining the critter (thereby killing it) and using X-rays to look inside.
Now scientists have worked out how to use a CT scanner, used in medical settings for high-powered X-rays, to look inside a living chrysalis. And they’ve produced this impressive time-lapse video revealing just what goes on in that hidden interior.
2.6-Billion-Year-Old Water Found in Reservoirs Under Canada
Outcrop of banded gneiss in the Canadian shield. Image courtesy of LesPalenik/Shutterstock
Newly discovered water trapped more than a mile below ground in Canada could be billions of years old — and could hold clues both to Earth’s past climate and possible habitats for life on Mars.
A research team reporting today in Nature has found pockets of subterranean water that could be as old as 2.64 billion years. The fluids are located 1.5 miles underground in a mine near Timmins, Ontario, in rock that is part of Canada’s Precambrian Shield, the oldest part of North America’s crust.
Fierce Winds Seen in Neptune and Uranus Jet Stream
A schematic of the jet streams on the planet Neptune. The atmospheric circulation is characterized by westward flow near the equator and an eastward flow at higher latitudes. Courtesy of Yohai Kaspi, Weizmann Institute of Science; NASA
In news that’s sure to delight young boys everywhere, scientists now have a better grasp on the impressive winds of Uranus. Neptune too. In a Nature study published today astronomers find that the most obvious weather patterns on the two ice giants are relatively shallow, only about 1,100 kilometers (683 miles) deep at most. The finding helps researchers understand the internal dynamics on Uranus, Neptune and similar exoplanets.
The two farthest planets from our sun might seem familiar to us, but much remains unknown about how they work. For instance, scientists had long known that the atmospheres of both worlds seemed to be dominated by fierce east-west jet streams—near the equator velocities reach 750 miles per hour, and at the poles approximately 560 mph.
But scientists didn’t know how the winds worked. Two theories soon developed: Either the winds were shallow phenomena, restricted to the upper atmosphere (remaining relatively shallow beneath the planet’s surface), or they were the result of some deeper planetary dynamics that could extend closer to the planets’ cores.
Markets Make Us Less Moral
Most of us would agree that harming others on purpose and for no reason is immoral. Social scientists have long assumed that marketplaces are to blame for many a compromised moral. There’s no shortage of historical examples: take the slave trade, or buying indulgences from the church, for instance. Now science has weighed in to confirm this hunch: a marketplace degrades a person’s morals.
That was what German researchers found in an experimental set-up that put people’s morals up against money in a market.
Minoans, First Advanced European Civilization, Originated From Europe Not Africa
Ancient jars in Knossos Palace, Greece. Photo by zz1969 / Shutterstock
The Minoans, considered the first advanced civilization in Bronze Age Europe, left behind massive building complexes, stunning artwork and hieroglyphs—but few clues about their origins.
Archaeologists first posited that the Minoans came to the Greek island of Crete from northern Africa, establishing themselves on the island about 5,000 years ago. Subsequent theories suggested Balkan or Middle Eastern origins for the civilization. But research published today in Nature Communications reveals both a more European, and home-grown, development.
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