One might think that identical-twin bacteria—clones of each other—would grow up and live very similarly. But a study published today in Science that examined individual bacterial cells in detail found that genetically identical E. Coli cells actually seem to express their genes quite differently, simply because of the random accidents of how their molecular machinery happens to operate.
“The paper is quite rich,” said Sanjay Tyagi, a molecular biologist at New Jersey Medical School who was not involved in the research [but published a perspectives piece on it]. “People think that if an organism has a particular genotype, it determines its phenotype [observable characteristics]–that there’s a one-to-one relationship,” said Tyagi. “But as it turns out, [differences in gene expression] can arise just from chance.” [The Scientist]
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Imagine an infantile version of our 4.6 billion-year-old sun. Now picture a “failed star,” a brown dwarf, about the size of Jupiter, tightly orbiting that 12 million year old stellar baby–at the distance Uranus orbits our sun. Astronomers have just found such a duo: a star about the mass of our sun with an unusually close brown dwarf companion.
Of the similarly situated brown dwarfs that astronomers have imaged, most keep their distance, orbiting at about 50 AU (or 50 times the average distance from the Earth to the sun). A team of astronomers believe the distance between this young sun, called PZ Tel A, and its dwarf companion, PZ Tel B, is less than half that, a mere 18 AU.
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In a medical sense, you’d be wise to steer clear of filoviruses, a group that includes the deadly Ebola, and bornaviruses, which cause neurological diseases. But in a genetic sense, it may not be possible to avoid them. A new study in PLoS pathogens shows that bits and pieces of these viruses have been floating around in the human genome, as well as those of other mammals and vertebrates, for millions of years.
It’s not that having genetic material left behind by viruses is odd—previous research had shown that viruses account for 8 percent of the human genome. But scientists thought most of that material came from retroviruses, which use their host’s DNA to replicate and leave some of their genetic material behind. What’s weird about this is that filoviruses and bornaviruses are not retroviruses—they’re RNA viruses, which don’t use the host to reproduce in the same way.
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Researchers camped on the Greenland ice sheet hit bedrock this week after almost three years of drilling, reaching a depth of 8,000 feet. They hope that the ice they’ve uncovered from some 120,000 years ago, might give them a better understanding of what a warmer future might look like, if Greenland has less ice and the sea level rises.
The team, which is part of the North Greenland Eemian Ice Drilling (NEEM) project, is looking to learn more about carbon dioxide levels during the Eemian period, when global temperatures were over 2-3 degrees Celsius warmer and sea level was about 15 feet higher. They believe these conditions might mirror effects caused by the earth’s changing climate during the next century.
Scientists believe that by the end of the 21st century the planet will experience similar conditions again. Over the Greenland ice sheet, temperatures at the height of the Eemian may have been around 5 degrees Celsius warmer–mirroring the Arctic amplification of modern climate change. . . There are large uncertainties concerning the response of ice sheets to warming air and ocean temperatures. Understanding what happened to the Greenland ice sheet during the Eemian could help constrain projections of future sea level rise. [Nature]
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They went to investigate solar wind-stirred storms in our planet’s magnetic field, but, after working for three years, two NASA solar-powered probes faced a dark demise, trapped in the Earth’s shadow. NASA researchers now think they can give the twin satellites another shot by altering their courses and sending them instead to study the moon.
NASA launched the probes in 2007 as a set of five identical satellites in the THEMIS Mission (Time History of Events and Macroscale Interactions during Substorms), meant to orbit Earth and send information during brief (2-3 hour) “substorms” when the magnetic field surrounding the Earth releases stored energy from solar winds. To understand the start of these “space tornadoes” responsible for the northern and southern lights, NASA placed the probes in very precise orbits, but for two craft that meant, one day, they would face prolonged battery-draining time in the Earth’s shadow.
“When we realized that the satellites would be going into very deep shadows, we started thinking of different methods for saving them–even before they were launched,” lead scientist Vassilis Angelopoulos, at the University of California, Berkeley, told Discovery News. “We realized that if we had enough fuel to change their orbits, the moon’s gravity would start pulling them up.”[Discovery News]
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Beware death from above! So blared science headlines yesterday. Citing a study in the Journal Icarus that said a huge asteroid perhaps could have a 1 in 1,000 shot of striking earth late in the next century, stories broke such as,
“Will a Giant Asteroid Kill Us All in 2182?”
“Asteroid Could Destroy Human Life on Earth by 2200”
“Huge asteroid on possible collision course with Earth (172 years from now)”
“Mark your calendars: Potentially hazardous asteroid might collide with Earth in 2182”
They’re correct in that there’s a giant asteroid out there called 1999 RQ36, and there’s a small chance it might hit us in a just less than couple hundred years. There’s just one problem: It isn’t news, though you wouldn’t have gotten that from the articles. The study everyone is referring to came out last year—it was in Icarus last October.
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A new device may one day save those with diabetes from the frequent finger-pricking and cumbersome external monitors required to check glucose levels–by instead keeping tabs from inside their torsos. In a study published online today in Science Translational Medicine, researchers report that an implantable glucose sensor has worked in pigs. Ultimately, clinical trials and FDA approval will determine if the device holds any promise for humans, but researchers say this animal test is an important first step.
“You can run the device for a year or more with it constantly working, and recording glucose quite satisfactorily. Now, we are focused on getting the human clinical trials going. We hope to begin the first human trial within in a few months,” said [lead author, David Gough.] “If all goes well with the human clinical trials, we anticipate that in several years, this device could be purchased under prescription from a physician,” said Gough.[University of California - San Diego]
As Popular Science reports, the device is “just a bit smaller than a Double-Stuf Oreo”–around 1.5 inches wide and half an inch thick. Gough and colleagues implanted the device in two pigs: one for 222 and and another for 520 days. It works by monitoring oxygen consumed in a chemical reaction with the enzyme glucose oxidase–the amount of oxygen consumed is proportional to the amount of glucose in the user’s blood. Though some already use similar sensors, none have lasted this long.
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The 2000s, the “aughts”—whatever you want to call the first decade of the 21st century, you can also call it the warmest 10 years on record. The National Oceanic and Atmospheric Administration just released its annual “State of the Climate” report, and after sampling 37 climate indicators including the biggies like sea surface temperature, glacier cover, and sea level, they came to that conclusion.
The NOAA report—published in the Bulletin of the American Meteorological Society—is different from other climate publications, because it’s based on observed data, not computer models, making it the “climate system’s annual scorecard,” the authors wrote… “It’s telling us what’s going on in the real world, rather than the imaginary world,” said Kevin Trenberth, a senior scientist at the Boulder, Colorado-based National Center for Atmospheric Research [National Geographic].
While one climate group trumpets its mountain of climate data, the scientists at the University of East Anglia are just climbing out from the scandal that broke out over theirs. This month another investigation cleared the Climate Research Unit of scientific misconduct or dishonesty, without condoning the emails’ tone or the unit’s handling of the controversy.
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When you hear mention of BPA, or bisphenol-A, plastic bottles and food containers likely come to mind. Now, a report presented by activists at the Environmental Working Group says the chemical is also in some paper store receipts.
In the study, which has not been peer reviewed, the environmental group looked for BPA in 36 sales receipts. They found that about forty percent used thermal paper (which has a chemical coating that changes colors when heated) that contained 0.8 to nearly 3 percent pure BPA by weight, 250 to 1,000 times greater than the amount of BPA typically found in a can of food or a can of baby formula. Other research, their report says, shows that BPA can transfer from receipts to a person’s skin, but how much BPA transfers or if it penetrates into the bloodstream remains uncertain. A chemical-industry trade group says the amount transferred is low:
“Available data suggests that BPA is not readily absorbed through the skin,” a spokeswoman from [The American Chemistry Council] said. “Biomonitoring data from the U.S. Centers for Disease Control shows that exposure to BPA from all sources, which would include typical exposure from receipts, is extremely low.”[Washington Post]
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Is this battery the one? Toshiba’s Super-Charge Ion Batteries, which reportedly lose hardly any capacity after thousands of charges, could be coming to cars next year.
As Slashdot noted today, this battery technology has been a long time coming. In 2007 Toshiba announced the creation of the SCiB, and unveiled the prototype the next year. It lasts 5,000 to 6,000 cycles as opposed to the 500 for standard lithium-ion batteries, and charges to 90 percent of capacity within five minutes. Earlier this month, the company announced it has been working with car maker Mitsubishi on electric vehicle batteries, and could be making SCiBs for cars staring next year.
For EV applications Toshiba has developed a new anode material and a new electrolyte to improve safety and rapid recharging. According to Toshiba, the long life will promote reduction in the waste that results from battery replacement, reducing the impact on the environment [Gizmag].
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Every time governments fail to take serious steps on climate change, it seems the parlor game of predicting what our warmer world will look like heats up. And the newest of those predictions, appearing this week in the Proceedings of the National Academy of Sciences, pokes at what is presently one of the country’s most sensitive spots: immigration.
Michael Oppenheimer of Princeton published a study that estimates that between 1.4 and 6.7 million people could become climate refugees emigrating from rural Mexico to the United States between now and 2080. That’s 2 to 10 percent of the present Mexican population, and it doesn’t include people who would make the move for other reasons.
Is it a major concern? Yes. How much stock should you put in those statistics? Not much.
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Lake Ontario has some key differences compared to her equally-sized sister lake, Ontario Lacus: The Great Lake has water; Ontario Lacus has methane, ethane, and propane. The Great Lake invites sunbathers; Lacus’ beaches, almost ten times further from the sun, are icy cold. The Great Lake is located on Earth; Lacus on Saturn’s largest moon, Titan. Despite all these distinctions, new research points to an important similarity: liquid levels in both lakes change with the seasons.
From June 2005 to July 2009, the Ontario Lacus shoreline has receded by about 6 miles, Alexander G. Hayes and his coauthors report in two papers submitted to Icarus and the Journal of Geophysical Research. Looking at other lakes in Titan’s southern hemisphere, it seems they are dropping in depth by about three feet per year.
Despite its shoreline’s rapid retreat, there is little worry that Ontario Lacus and other Titan lakes will disappear forever. Scientists expect that the evaporation is just part of a cycle of evaporation and condensation, that changes with the seasons. The four years of observation, carried out by NASA’s Cassini spacecraft, represents only the period from about mid-summer to fall, since a Titan year lasts 29.5 Earth years.
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Every three years the Librarian of Congress reviews the Digital Millennium Copyright Act (DMCA), and James H. Billington’s review just expanded digital freedom with this year’s ruling of new exemptions to the copyright law.
Jailbreak that iPhone
First and foremost, Billington ruled that it’s not against the law to jailbreak a phone (the practice of working around the device’s security system and taking more direct control of it). The Electronic Frontier Foundation lobbied hard for this, particularly with the iPhone in mind. Because Apple keeps tight reins on the device—offering only AT&T phone service and acting as gatekeeper for what apps can be added—many people had taken to jailbreaking the phone.
About 4 million iPhone and iPod Touch units had been jailbroken as of last August, and were accessing apps from a sort of black-market storefront called Cydia, the marketplace’s founder told Wired. The store is a haven for many developers that Apple, the gatekeeper to its App Store, has ignored or turned away [Los Angeles Times].
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Particle physicists hunting for the Higgs boson reported their latest findings yesterday at the International Conference on High Energy Physics in Paris. The big two–Europe’s Large Hadron Collider and Fermilab’s Tevatron Collider (in Illinois)–gave updates, and other conference buzz included talk of a new facility, the International Linear Collider, which may one day give physicists a cleaner look at the other colliders’ results.
Large Hadron Collider — More Detailed Models Help the Search
Currently operating at 7 Tera electron Volts (TeV), the Large Hadron Collider is the world’s most powerful particle accelerator. Though electrical malfunctions hindered the collider in 2008, now LHC scientists report that they have made up for lost time: finding in months, what took the Tevatron, with its 2 TeV collisions, decades.
“The scientific community thought it would take one, maybe two years to get to this level, but it happened in three months,” said Guy Wormser, a top French physicist and chairman of the conference.[AFP]
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You may be talking and I may be listening, but our brains look strikingly similar.
That’s the conclusion of a study in the Proceedings of the National Academy of Sciences this week. After conducting brain scans of a woman telling a story off the cuff and then of 11 people listening to a recording of her, researchers Greg Stephens and Uri Hasson say they found that the same parts of the brains showed activation at the same time, suggesting a deep connection between talker and listener.
Graduate student Lauren Silbert was the team’s storytelling guinea pig. She recounted tales of high school, like deciding whom to take to prom, while undergoing an fMRI scan.
As Silbert spoke about her prom experience, the same areas lit up in her brain as in the brains of her listeners. In most brain regions, the activation pattern in the listeners’ brains came a few seconds after that seen in Silbert’s brain. But a few brain areas, including one in the frontal lobe, actually lit up before Silbert’s, perhaps representing listeners’ anticipating what she was going to say next, the team says [ScienceNOW].
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