The psychostimulant methylphenidate, known by the brand name Ritalin, is used as part of a treatment program to the control symptoms of attention deficit hyperactivity disorder (ADHD).  Symptoms of ADHD starts before the age of seven years and  affects about 3 to 5 percent of children world-wide. Millions of individuals diagnosed with ADHD are treated by Ritalin.

Many animals produce alarm calls to predators, and do this more often when kin or mates are present than other audience members. So far, however, there has been no evidence that they take the other group members' knowledge state into account.

When it comes to love songs, female tree frogs are pretty picky. According to a new study from the University of Missouri, certain female tree frogs may be remarkably attuned to the songs of mates who share the same number of chromosomes as they do. The researchers found female frogs can hear chromosome difference in the calls of potential mates.

Why were some dinosaurs able to get so much larger than today's terrestrial mammals? It was hypothesized that large dinosaurs might have faced a lower risk of extinction under ecological changes than similar-sized mammals, because large dinosaurs had a higher potential reproductive output than similar-sized mammals (JC hypothesis).

Imagine if the next coat of paint you put on the outside of your home generates electricity from light—electricity that can be used to power the appliances and equipment on the inside.

A team of researchers at the University of Notre Dame have created an inexpensive "solar paint" that uses semiconducting nanoparticles to produce energy.

In order to get a better picture of our surroundings, the brain has to integrate information from different senses, but how does it know which signals to combine? New research has demonstrated that humans exploit the correlation between the temporal structures of signals to decide which of them to combine and which to keep segregated.

In a new research report scientists now describe a combination of direct gene-cloning technology with the human artificial chromosome- based vector for gene delivery. Gene delivery, one of the steps necessary for gene therapy, is the process of introducing foreign genes into host cells.