Astronomers have long suspected the existence of the invisible substance of dark matter as the source of additional gravity that holds together galaxy clusters. Otherwise, astronomers say, the clusters would fly apart if they relied only on the gravity from their visible stars. Although astronomers don't know what dark matter is made of, they hypothesize that it is a type of elementary particle that pervades the Universe.

In a result just published, astronomers using the NASA/ESA Hubble Space Telescope report the discovery of a ring of dark matter in the cluster ZwCl0024+1652.

Hormones in children's saliva may be a biological indicator of the trauma kids undergo when they are chronically bullied by peers, according to researchers who say biological markers can aid in the early recognition and intervention of long-term psychological effects on youth.

"Bullying is mainly self-reported either by students or observed by teachers," said JoLynn V. Carney, associate professor of counselor education at Penn State.

The outbreak of severe acute respiratory syndrome (SARS) in 2002 was a loud wake-up call for researchers studying infectious diseases. SARS infected over 8,000 people, killed 10 percent of those infected, and weakened most with pneumonia.

"The SARS outbreak was a strong reminder that new viruses can emerge, and whether new or old, pathogens can cause not only significant disease and death, but they can also have a global socioeconomic impact," said Brenda Hogue, an associate professor in the Biodesign Institute’s Center for Infectious Diseases and Vaccinology and School of Life Sciences. Hogue has been involved in a big push to uncover some of the key clues behind coronavirus illness.

Molecular studies recently revealed new genetic information concerning the long-disputed origin of the “European potato.” Scientists from the University of Wisconsin-Madison, the University of La Laguna, and the International Potato Center used genetic markers to prove that the remnants of the earliest known landraces of the European potato are of Andean and Chilean origin.

“European potatoes,” the cultivated potatoes first appearing in Europe and later spreading worldwide, were first recorded outside of the Americas in 1567 on the Canary Islands Archipelago. Today, scientists believe that the remnant landraces of these early potatoes still grow in on the Canary Islands.

Antipsychotic drugs do most of their work in the brain, but they also leave behind in the bloodstream a trail of hundreds of chemicals that may be used in the future to direct better treatment for schizophrenia and other psychiatric conditions, say Duke University Medical Center researchers.

The study is among the first to use metabolomics -- the measurement of thousands of chemical byproducts of the body's cellular processes -- to look at a psychiatric disease and its response to therapy, according to the researchers.

Keeping at arm's length won't protect you from catching an infectious disease, according to new research by Queensland University of Technology which reveals airborne viruses can spread far and wide.

Professor Lidia Morawska, director of QUT's International Laboratory for Air Quality and Health, said the study dispelled the myth that viruses emitted from humans only travel a metre in the air.