Oxygen is indispensable to animal and plant life, but its presence in the wrong places can feed a fire and cause iron to rust.

In the fabrication of solid state lighting devices, scientists are learning, oxygen also plays a two-edged role. While oxygen can impede the effectiveness of gallium nitride (GaN), an enabling material for LEDs, small amounts of oxygen in some cases are needed to enhance the devices' optical properties. GaN doped with europium (Eu), which could provide the red color in LEDs and other displays, is one such case.

Among adults with Clostridium difficile infection that is recurrent or not responsive to treatment, the use of frozen compared with fresh fecal microbiota transplantation (FMT) did not result in a significantly lower rate of resolution of diarrhea, indicating that frozen FMT may be a reasonable treatment option for these patients. 

A songbirds' vocal muscles work like those of human speakers and singers, finds a new study. The research on Bengalese finches showed that each of their vocal muscles can change its function to help produce different parameters of sounds, in a manner similar to that of a trained opera singer.

Pitch, for example, is important to songbird vocalization, but there is no single muscle devoted to controlling it. They don't just contract one muscle to change pitch, they have to activate a lot of different muscles in concert, and these changes are different for different vocalizations. Depending on what syllable the bird is singing, a particular muscle might increase pitch or decrease pitch.

ST. LOUIS - Opioids may cause short-term improvement in mood, but long-term use imposes risk of new-onset depression, a Saint Louis University study shows.

For half a century, cancer researchers have struggled with a confusing paradox: If cancer is caused by the occurrence and accumulation of cancer-causing (oncogenic) mutations over time, young children should get less cancer since they have fewer mutations.

So why do young children have a higher incidence of leukemia than teenagers and young adults? 

NEW YORK, NY (Jan. 6, 2016) -- A new study conducted at Columbia University Medical Center (CUMC) has revealed some of the underlying mechanisms that may increase the risk of heart disease in people with sleep apnea. The study also found that statins -- the cholesterol-lowering medications commonly prescribed to combat heart disease -- may help reverse this process.

The study was published in the Jan. 6, 2016 online edition of Science Translational Medicine.