Earth

The physics community has spent three decades searching for and finding no evidence that dark matter is made of tiny exotic particles. Case Western Reserve University theoretical physicists suggest researchers consider looking for candidates more in the ordinary realm and, well, more massive.

Dark matter is unseen matter, that, combined with normal matter, could create the gravity that, among other things, prevents spinning galaxies from flying apart. Physicists calculate that dark matter comprises 27 percent of the universe; normal matter 5 percent.

Urban legend states that New York City has as many rats as people: roughly 8 million; but a new analysis suggests there are nowhere near as many.

The analysis classified rat sightings by city lot, of which there are roughly 842,000 in New York City. The researchers estimated 40,500 rat-inhabited lots in the city. By liberally assuming that 40 to 50 rats belong to a typical colony and that one full colony occupies each rat-inhabited lot, the researchers concluded that 2 million would be an extremely generous estimate of the city's rat population.

New research indicates that scent associated with polar bear paws conveys information that may affect the animals' social and reproductive behavior. This chemical form of communication was likely shaped by the environmental constraints of Arctic sea ice.

Scientists worry that this communication may be impacted if scent trails are disrupted due to increased fracturing of sea ice from climate change.

A geologist in Syracuse University's College of Arts and Sciences has demonstrated that earthquakes--not climate change, as previously thought--affect the rate of landslides in Peru.

The finding is the subject of an article in Nature Geoscience (Nature Publishing Group, 2014) by Devin McPhillips, a research associate in the Department of Earth Sciences. He co-wrote the article with Paul Bierman, professor of geology at The University of Vermont; and Dylan Rood, a lecturer at Imperial College London (U.K.).

New research indicates that bald and golden eagles in North America may be exposed to dangerously high levels of polybrominated diphenyl ethers (PBDEs), which are chemicals used in the production of a wide variety of textiles, plastics, and electronics.

Investigators analyzed the livers of 33 bald eagles and 7 golden eagles collected throughout Washington and Idaho, finding that eagles associated with large urban areas had the highest PBDE concentrations.

Childhood behavioral conditions such as attention deficit hyperactivity disorder and conduct disorder are linked with an increased risk of being convicted of a felony later in life, with heavy drinking and educational failure contributing to this link.

The findings, which come from an analysis of 4,644 men, suggest that substance use and educational disengagement in adolescence operate as stepping stones toward adult criminality among behaviorally disordered children.

Even during summer dry spells, some isolated patches of soil in forested watersheds remain waterlogged.

These patches act as hot spots of microbial activity that remove nitrogen from groundwater and return it to the atmosphere, researchers from several institutions, including Virginia Tech, report in a leading scientific journal.

The discovery provides insight into the health of a forest. Nitrogen is an important nutrient for plant growth and productivity, but in streams, it can be a pollutant.

ITHACA, N.Y. – Even during summer dry spells, some patches of soil in forested watersheds remain waterlogged. Researchers have discovered that these patches act as hot spots of microbial activity that remove nitrogen from groundwater and return it to the atmosphere, as reported in a Nov. 3 article in Proceedings of the National Academy of Sciences.

Nitrogen is a critically important nutrient for plant growth in the forest. Denitrification removes this nutrient from the ecosystem and can reduce the growth and productivity of the forest.

Targeting emissions of non-CO2 gases and air pollutants with climate effects might produce smaller benefits for long-term climate change than previously estimated, according to a new integrated study of the potential of air pollution and carbon dioxide mitigation.

High hopes have been placed on limiting emissions of so-called short-lived climate forcers (SLCF) such as methane and soot for protecting human health, vegetation and limiting temperature increase.

In a study published today in PNAS, Dr William Roberts of Bristol's School of Geographical Sciences and colleagues use computer models to simulate a Heinrich event in Hudson Bay, Canada, adjusting the models to consider freshwater influx only, changing ice sheet height only or both factors together.

Two USC researchers have proposed a link between string field theory and quantum mechanics that could open the door to using string field theory — or a broader version of it, called M-theory — as the basis of all physics.

"This could solve the mystery of where quantum mechanics comes from," said Itzhak Bars, USC Dornsife College of Letters, Arts and Sciences professor and lead author of the paper.

Bars collaborated with Dmitry Rychkov, his Ph.D. student at USC. The paper was published online on Oct. 27 by the journal Physics Letters.

WASHINGTON, Nov. 3, 2014 — As Carl Sagan famously said, "We are made of star stuff." It's a mind-boggling thought, but what exactly did he mean? Ahead of Sagan's birthday on November 9th, Reactions teamed up with the American Association of Chemistry Teachers (AACT) and best-selling author Sam Kean to explain the chemistry behind this iconic quote. Watch our latest episode to find out how many of the atoms that make up you (and everything else) were forged in the nuclear cores of stars billions of years ago.

NOAA's GOES-West satellite captured an image of Hurricane Vance and a much smaller developing low pressure area in the Eastern Pacific Ocean on Nov. 3. Vance's tropical-storm force winds extended to about 250 miles in diameter.

New York | Heidelberg, 3 November 2014 -- A new theoretical work establishes a long-sought-after connection between nuclear particles and electromagnetic theories. Its findings suggest that there is an equivalence between generalised Casimir forces and those that are referred to as weak nuclear interactions between protons and neutrons. The Casimir forces are due to the quantisation of electromagnetic fluctuations in vacuum, while the weak nuclear interactions are mediated by subatomic scale particles, originally called mesons by Yukawa.

WASHINGTON, Nov. 3, 2014 — As Carl Sagan famously said, "We are made of star stuff." It's a mind-boggling thought, but what exactly did he mean? Ahead of Sagan's birthday on November 9th, Reactions teamed up with the American Association of Chemistry Teachers (AACT) and best-selling author Sam Kean to explain the chemistry behind this iconic quote. Watch our latest episode to find out how many of the atoms that make up you (and everything else) were forged in the nuclear cores of stars billions of years ago.