*Pregnant women whose sisters had condition are 17 times more likely to have it*
Approximately 60,000 pregnant women are hospitalized each year due to hyperemesis gravidarum (HG), an extreme form of nausea and vomiting that endangers their lives and often forces them to reluctantly terminate their pregnancies.
And for women with sisters, mothers and grandmothers on either side of the family who have experienced extreme morning sickness during pregnancy, the risk of HG may be heightened, according to a new study led by researchers from UCLA and the University of Southern California.(more…)
Scientists have long known that large volcanic explosions can affect the weather by spewing particles that block solar energy and cool the air.
Some suspect that extended “volcanic winters” from gigantic eruptions helped kill off dinosaurs and Neanderthals.
In the summer following Indonesia’s 1815 Tambora eruption, frost wrecked crops as far away as New England, and the 1991 blowout of the Philippines’ Mount Pinatubo lowered average global temperatures by 0.7 degrees F — enough to mask the effects of greenhouse gases for a year or so. (more…)
Melt water flowing through ice sheets via crevasses, fractures and large drains called moulins can carry warmth into ice sheet interiors, greatly accelerating the thermal response of an ice sheet to climate change, according to a new study involving the University of Colorado at Boulder.
The new study showed ice sheets like the Greenland Ice Sheet can respond to such warming on the order of decades rather than the centuries projected by conventional thermal models. Ice flows more readily as it warms, so a warming climate can increase ice flows on ice sheets much faster than previously thought, said the study authors. (more…)
A model representation of telomerase's RNA "core domain," determined by Juli Feigon, Qi Zhang and colleagues in Feigon's UCLA laboratory. Image credit: Juli Feigon, UCLA Chemistry and Biochemistry/PNAS
Telomerase is an enzyme that maintains the DNA at the ends of our chromosomes, known as telomeres. In the absence of telomerase activity, every time our cells divide, our telomeres get shorter. This is part of the natural aging process, as most cells in the human body do not have much active telomerase. Eventually, these DNA-containing telomeres, which act as protective caps at the ends of chromosomes, become so short that the cells die.
But in some cells, such as cancer cells, telomerase, which is composed of RNA and proteins, is highly active and adds telomere DNA, preventing telomere shortening and extending the life of the cell.
UCLA biochemists have now produced a three-dimensional structural model of the RNA “core domain” of the telomerase enzyme. Because telomerase plays a surprisingly important role in cancer and aging, understanding its structure could lead to new approaches for treating disease, the researchers say.(more…)
*Petunias show that the mechanisms behind inbreeding prevention are similar to immune response*
About the image: The female part of the petunia flower secretes an enzyme that is designed to deter pollen tube growth, thereby preventing fertilization. However, in the cases that the pollen has come from a genetically different plant, the pollen produces its own protein that combats the pistil’s enzyme. With the enzyme out of the way, the pollen tube can keep growing and fertilization can occur. Image credit: Zina Deretsky, National Science Foundation
Inbreeding is a bad strategy for any organism, producing weak and problematic offspring. So imagine the challenge of inbreeding prevention in a plant where male and female sexual organs grow right next to each other! Such is the genetic conundrum faced by the petunia. (more…)
ANN ARBOR, Mich.—A unique disaster-response planning tool takes real-time human decision-making into account to determine effective law-enforcement strategies during evacuations. A University of Michigan researcher contributed to the development of the tool. (more…)
*Sponsored by Buick, Weekend Edition offers content for the weekend audience, including an original video program*
SUNNYVALE, Calif.–(BUSINESS WIRE) — Yahoo! and Buick today unveiled Weekend Edition on Yahoo! News, a new weekend programoffering compelling original video and relevant editorial content, programmed for the weekend audience. Weekend Edition (https://weekendedition.news.yahoo.com) will help Buick reach and engage the Yahoo! News audience of more than 90 million monthly visitors by integrating the Buick brand in a premium-content environment.
“With Weekend Edition, we’ve established a destination that features lighter lifestyle-oriented news programming, which we already know is more popular with our weekend audience,” said Mark Walker, vice president and head of Yahoo! News. “This program also aligns perfectly with Buick’s target demographics and brand attributes, which makes Buick an ideal partner for Weekend Edition.” (more…)
The green Voorwerp in the foreground remains illuminated by light emitted up to 70,000 years ago by a quasar in the center of the background galaxy, which has since died out. Image credit: WIYN/William Keel/Anna Manning
While sorting through hundreds of galaxy images as part of the Galaxy Zoo citizen science project two years ago, Dutch schoolteacher and volunteer astronomer Hanny van Arkel stumbled upon a strange-looking object that baffled professional astronomers. Two years later, a team led by Yale University researchers has discovered that the unique object represents a snapshot in time that reveals surprising clues about the life cycle of black holes.
In a new study, the team has confirmed that the unusual object, known as Hanny’s Voorwerp (Hanny’s “object” in Dutch), is a large cloud of glowing gas illuminated by the light from a quasar-an extremely energetic galaxy with a supermassive black hole at its center. The twist, described online in the Astrophysical Journal Letters, is that the quasar lighting up the gas has since burned out almost entirely, even though the light it emitted in the past continues to travel through space, illuminating the gas cloud and producing a sort of “light echo” of the dead quasar. (more…)
