Mouse body clock study offers clues to possible jet lag cure

LONDON | Thu Aug 29, 2013 12:22pm EDT

LONDON (Reuters) - Scientists have found a genetic mechanism in mice that hampers their body clock's ability to adjust to changes in patterns of light and dark, and say their results could someday lead to the development of drugs to combat jet lag.

Researchers from Britain's Oxford University and from the Swiss drug firm Roche used mice to analyze patterns of genes in an area of the brain called the suprachiasmatic nuclei (SCN) - which in mammals pulls every cell in the body into the same biological rhythm.

They found that one molecule, called SIK1, is key to how the mice responded to changes in light cycles.

When the scientists blocked the activity of SIK1, the mice recovered faster from disturbances in their daily light and dark cycle that had been designed to induce a form of mouse jet lag.

If the corresponding mechanism can be found and similarly blocked in humans, jet lag may become a thing of the past, the researchers said in their study, published online in the journal Cell on Thursday.

"We're still several years away from a cure for jet lag, but understanding the mechanisms that generate and regulate our circadian clock gives us targets to develop drugs to help bring our bodies in tune with the solar cycle," said Russell Foster, director of Oxford's sleep and circadian neuroscience institute.

He said such drugs could also have broader potential value, including for people with mental illnesses where sleep disturbances are common.

(Reporting by Kate Kelland; Editing by Sonya Hepinstall)

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Super-CDMS researchers report possible evidence of WIMPs

(Phys.org) —Researchers working at the Super Cryogenic Dark Matter Search (CDMS) facility, located underground in Minnesota's Soudan Mine, are reporting in a paper uploaded to the preprint server arXiv that they've found three events that lie in the signal range of Weakly Interacting Massive Particles (WIMPs). The group also gave a talk detailing their results to an audience at this year's American Physical Society meeting—as part of that discussion, they made it clear the noted events do not rise to the level of discovery, nor do they imply the team has found evidence of the existence of dark matter.

Researchers in several facilities around the world (and aboard the International Space Station) are looking for evidence of WIMPs, because theory suggests that they constitute dark matter, the invisible material believed to make up approximately 85 percent of all matter that exists in the universe. Because WIMPs can't be seen directly, researchers look to events that might prove they exist, such as collisions between WIMPs and atomic nuclei. In order to find such evidence, researchers set up detectors they hope will catch such collisions that occur due to gravitational pull on WIMPs—they are believed to interact only rarely with normal matter through other means.

Enlarge

The Cryogenic Dark Matter Search experiment uses five towers of dark matter detectors like the ones shown here. Credit: Fermilab

Researchers at the Super-CDMS facility have set up eight silicon detectors (cooled to -459.67 degrees Fahrenheit) in the hope of detecting the slight amount of heat given off by a collision between a WIMP and an atom's nucleus. The researchers report detection of three events that might have been the result of such collisions, though they are quick to add that the events might also have been due to something else, such as statistical errors. However, calculations indicate the events are 99.81 percent more likely to be WIMPs than background fluctuations, which translates to approximately a three-sigma level of confidence.

Interestingly, if the detected events do turn out to be the result of WIMP/nucleus collisions, it will mean that WIMPs are much lighter than scientists have been expecting—the detected collisions detected to just 8.6 giga-electronvolts. The researchers note this finding is in line with results from other research efforts, though they also acknowledge that it contradicts the findings of other researchers. Regardless, research at the Super-CDMS facility and elsewhere will continue until WIMP collisions are proven to exist, or not.

More information: Dark Matter Search Results Using the Silicon Detectors of CDMS II. arXiv astro-ph.CO, (2013)
Silicon Detector Results from the First Five-Tower Run of CDMS II. arXiv astro-ph.CO, (2013), arXiv:1304.3706
E. Figueroa-Feliciano's presentation at Light Dark Matter 2013.

cdms.berkeley.edu/

Journal reference: arXiv

© 2013 Phys.org

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U.S. blizzard, possible tornadoes forecast in nasty weather week

By Kevin Murphy

KANSAS CITY, Kansas | Mon Apr 8, 2013 5:31pm EDT

KANSAS CITY, Kansas (Reuters) - Forecasters called for strong hail and possible tornadoes in western Kansas and a blizzard in four other states on Monday in the first of what are expected to be several days of nasty weather in the middle of the country.

The blizzard was expected to hit Colorado, Nebraska, South Dakota and Wyoming on Monday. An Arctic cold front has triggered winter weather warnings over most of Colorado, said National Weather Service meteorologist Jim Kalina.

Meanwhile, warm air from the south mixing with cold air from Colorado is expected to cause severe weather in western Kansas, including possible tornadoes, said weather service meteorologist Matt Gerard, based in Dodge City, Kansas.

"It's a clash of air masses going on," Gerard said, adding that forecasts call for large hail in western Kansas.

Denver and its urban area could get up to 11 inches of snow overnight and through Tuesday, said Kalina. He said temperatures could plunge some 40 degrees from the mid-60s on Monday to well below freezing when the front moves through.

Areas from Denver to Rapid City, South Dakota; Casper, Wyoming; and Scottsbluff, Nebraska are expected to see blizzard conditions between Monday night and Tuesday, with plunging temperatures, high winds and heavy snow, according to Accuweather.com. The blizzard is forecast to move into north central Nebraska and central Minnesota later Tuesday into Wednesday.

South Dakota transportation officials advised travelers to move up travel plans to reach intended destinations during daylight hours, and be prepared to stay in until the storm passes. Heavy snowfall is expected, from 3 to 16 inches in the state, with winds up to 40 miles per hour.

The nasty weather will move toward more populated areas on Tuesday evening, with hail, damaging winds and some possibility of tornadoes predicted around Kansas City, Oklahoma City, and the Dallas-Fort Worth area in Texas, according to Robert Thompson, lead forecaster with the National Storm Prediction Center in Norman, Oklahoma.

Forecasters expect the front to hit Arkansas Wednesday afternoon and evening, with a line of thunderstorms expected to bring as much as three inches of rain and damaging winds, according to the National Weather Service.

The tornado season in the United States typically starts in the Gulf Coast states in the late winter, and then moves north with the warming weather, peaking around May and trailing off by July.

(Reporting by Kevin Murphy in Kansas City, Suzi Parker in Arkansas, Keith Coffman in Denver and Mary Wisniewski in Chicago; Editing by Scott Malone, Sofina Mirza-Reid, Greg McCune and James Dalgleish)

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