Science & TechnologyS


Info

Mother's diet at time of conception may alter baby's DNA

Woman Eating
© ShutterstockA woman's diet at the time of conception might cause lasting changes in the DNA of her children, according to researchers.
A woman's diet at the time of conception might cause lasting changes in the DNA of her children, potentially influencing their development, researchers say.

In a new study, researchers analyzed the diets of women in rural parts of The Gambia, in western Africa, who experience major changes in their diets over the course of each year as the area goes through rainy seasons and dry seasons.

"The rainy season is often referred to as 'the hungry season,' and the dry season 'the harvest season,'" said study author Robert Waterland, a nutritional epigeneticist at Baylor College of Medicine in Houston.

"During the rainy season, villagers have a lot more farming labor to do, and they gradually run out of food collected from the previous harvest."

Yearlong staples of the women's diet include rice, a grain called millet, peanuts and cassava. But during the rainy season, they eat more leafy green vegetables similar to spinach, which are very high in folate, a nutrient that is especially important during pregnancy.

The scientists investigated the concentration of nutrients in the blood of 84 pregnant women who conceived at the peak of the rainy season and 83 women who conceived at the peak of the dry season. In addition, they analyzed the DNA of six specific genes in the women's infants when they were 2 to 8 months old.

The researchers found that in all six genes, the infants who were conceived during the rainy season had consistently higher rates of "methylation" in their DNA. A methylation is a change made to DNA - it's the addition of methyl groups to the DNA strand, a so-called epigenetic modification to DNA - and is a process that can silence the expression of a gene.

Info

New genetic test reveals your ancestral origin

Origins
© Eran Elhaik et al, Nature CommunicationsGeographic origin of worldwide populations.
For centuries, scientists have sought a biological method for tracing a person's geographic origin. Now, a group of researchers has developed such a genetic ancestry test that can pinpoint the location where a person's ancestors originated more than 1,000 years ago.

The genetic algorithm accurately predicts the country of ancestral origin for about 80 percent of people, and for isolated island populations, it can predict people's island or even village of origin in some cases, researchers report today (April 29) in a study published in the journal Nature Communications.

A person's DNA contains more than simple instructions - it also tells the story of their evolution, migrations, interbreeding and mixing, said study leader Eran Elhaik, a population geneticist at the University of Sheffield in England.

"Only genetic tools can access this vast archive and extract the exact information about our geographic origin," Elhaik told Live Science.

Researchers have been attempting to use genetic data to trace human origins for decades. The best efforts have been able to accurately trace ancestral place of origin within about 435 miles (700 kilometers) in Europe, but not very accurately in other countries.

Fireball 5

Dark matter could send asteroids crashing into Earth: New theory

Impact Event
© Don DavisArtist’s impression of a 6-mile-wide asteroid striking the Earth. Scientists think approximately 70 of these dinosaur killer-sized or larger asteroids hit Earth between 3.8 and 1.8 billion years ago.
Dark matter could sling lethal meteors at Earth, potentially causing mass extinctions like the cataclysm that ended the Age of Dinosaurs, Harvard scientists say.

Physicists think the mysterious, invisible substance called dark matter makes up five-sixths of all matter in the universe. It was first detected by the strength of its gravitational pull, which apparently helps keep the Milky Way and other galaxies from spinning apart, given the speeds at which they whirl.

Scientists have recently suggested that a thin, dense disk of dark matter about 35 light-years thick lies along the central plane of the Milky Way, cutting through the galaxy's disk of stars. The sun travels in an up-and-down, wavy motion through this plane while orbiting the center of the galaxy.

Researchers suggest this disk of clouds and clumps made of dark matter might disturb the orbits of comets in the outer solar system, hurling them inward. This could lead to catastrophic asteroid impacts on Earth, of the kind that likely ended the Age of Dinosaurs, said theoretical physicists Lisa Randall and Matthew Reece at Harvard University.

Sun

Exposure to sunlight in the morning tied to weight loss

Image
© 1ms.net
Light might make you a lightweight - in a good way. It's been known that bright light in the morning can reduce appetite and body weight. But that fact did not prove that light has a direct effect on weight. Early morning exposure to light could just be a marker for a regular sleep cycle, which is also associated with a healthy body weight.

The question was thus whether light exposure was associated with weight regardless of sleep patterns.

To find out, researchers had 54 adults record their diet and sleep for a week. The subjects also wore sensors that monitored the timing and intensity of their light exposure.

Satellite

Astronaut twins to participate in NASA space travel study

twin astronauts
© NBC NewsWire/NBCU Photo Bank via Getty ImagesMark Kelly (left) will stay on Earth while his brother, Scott Kelly, spends a year on the International Space Station. NASA will test how the environments affect them differently.
This month, NASA revealed new details of the plan to send humans to Mars by 2030. It's an elaborate and expensive mission, involving a giant deep-space rocket, and roping an asteroid into the moon's orbit to use as a stepping stone to Mars.

But there are still some serious questions about a manned expedition to Mars. Namely, is it safe? That's where astronauts Scott and Mark Kelly come in. The Kelly brothers are identical twins, and the only siblings ever to both fly in space.

Starting next March, Scott Kelly will spend a year at the International Space Station. While he's up there, he will be a part of some novel scientific experiments comparing his health to his brother's down on Earth.

Water

Water was flowing on Mars 200,000 years ago

Mars
© NASAMars
New research has suggested that water was flowing across the surface of Mars some 200,000 years ago. The nature of rock formations in a Mars crater suggests the sediment deposits and channels it contained were formed by 'recent' flowing water.

Swedish scientists from the Department of Earth Sciences at the University of Gothenburg identified"Very young ...and well-preserved deposits of water bearing debris flows in a mid-latitude crater on Mars,"according to the study published in the journal Icarus.

It was previously estimated that liquid water flowed across the Red Planet during its last 'ice-age', some 400,000 years ago. However, the young age of the crater means the features signifying water must have appeared since.

Magnify

California scientists go underground to monitor Hayward Fault - San Andreas Fault's sibling

Image
© ABC
Cutting a direct path through the East Bay hills, the Hayward Fault is the San Andreas Fault's less-celebrated sibling. Yet it's a seismic threat the U.S. Geological Survey has described as 'a tectonic time bomb' - ready to rupture - bringing devastation to the Bay Area.

Now, scientists at UC Berkeley hope to get a jump on the fault's next big move.

The last major quake on the Hayward Fault was in the mid-1800s, before the region became packed with properties worth an estimated $1.5 trillion.

The fault has been pretty quiet since that 6.8 magnitude event but, today, a shaker that strong could buckle Interstate 80, I-880 and partially collapse the Caldecott Tunnel - even damaging the supposedly quake-resilient new eastern span of the Bay Bridge.

Cell Phone

Nokia finalises Microsoft handset deal

Nokia
© GettyNokia will sell its handset business to Microsoft for a "slightly higher" price than the earlier quoted 5.44 billion euros.
The former Finnish telecom giant Nokia completed the sale to Microsoft of its once iconic handset business on Friday, leaving factories in India and Korea out of the deal.

The company said that the value of the transfer announced in September, would be "slightly higher" than the earlier quoted price of 5.44 billion euros ($NZ8.77 billion).

The final figure would be decided on the basis of "the verified balance sheet", it said in a statement.

The US software giant Microsoft agreed to exclude factories in Chennai in southern India and in South Korea.

Question

Unique mineral discovered In Australia

Putnisite
© P. Elliott et alPurple mineral - Crystals of putnisite, in purple.
A previously unknown mineral has been discovered in a remote location in Western Australia. The mineral, named putnisite, appears purple and translucent, and contains strontium, calcium, chromium, sulphur, carbon, oxygen and hydrogen, a very unusual combination.

While dozens of new minerals are discovered each year, it is rare to find one that is unrelated to already-known substances. "Most minerals belong to a family or small group of related minerals, or if they aren't related to other minerals they often are to a synthetic compound--but putnisite is completely unique and unrelated to anything," said Peter Elliott, co-author of a study describing the new substance and a researcher at the South Australian Museum and the University of Adelaide, in a statement. "Nature seems to be far cleverer at dreaming up new chemicals than any researcher in a laboratory."

It appears as tiny semi-cubic crystals and is often found within quartz. Putnisite is relatively soft, with a Mohs hardness of 1.5 to 2 (out of 10), comparable to gypsum, and brittle. It's unclear yet if the mineral could have any commercial applications.

Putnisite was discovered during prospecting for a mine at Lake Cowan in southwestern Australia, and is named after mineralogists Andrew and Christine Putnis. Mineral names are usually proposed by the discoverer, as in this case, but must be approved by the International Mineralogical Association.

Telescope

NASA's telescopes find coldest known brown dwarf

brown dwarf concept art
This artist's conception shows the object named WISE J085510.83-071442.5,
NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope have discovered what appears to be the coldest "brown dwarf" known - a dim, star-like body that, surprisingly, is as frosty as Earth's North Pole.

Images from the space telescopes also pinpointed the object's distance to 7.2 light-years away, earning it the title for fourth closest system to our sun. The closest system, a trio of stars, is Alpha Centauri, at about 4 light-years away.

"It's very exciting to discover a new neighbor of our solar system that is so close," said Kevin Luhman, an astronomer at Pennsylvania State University's Center for Exoplanets and Habitable Worlds, University Park. "And given its extreme temperature, it should tell us a lot about the atmospheres of planets, which often have similarly cold temperatures."