science newsletter: Science News SciGuru.com

Κυριακή 11 Μαρτίου 2012

Science News SciGuru.com

Crush hour in the test-tube: Overcrowding spoils the law of mass action
Introducing plug-and-play nanoelectromechanical systems (NEMS)
Exotic new matter expected in ultracold atoms
Maryland Study Urges Workplace Policies to Prevent Postpartum Depression, Save Costs
Gravitational lens reveals details of distant, ancient galaxy
Perceptions of Discrimination May Adversely Affect Health of Immigrants’ Children, Study Shows

Crush hour in the test-tube: Overcrowding spoils the law of mass action

Posted: 11 Mar 2012 05:47 AM PDT

The rate at which two chemical species react with one another is partly determined by the probability that they will collide. The so-called law of mass action explicitly takes account of this fact, stating that the reaction rate is dependent on the product of the concentrations of participating reactants. With the aid of mathematical modeling, LMU Professor Erwin Frey and his PhD student Anton Winkler at the Arnold Sommerfeld Center for Theoretical Physics have taken a new look at the validity of the law. They show that it is violated when particle densities become sufficiently high.

Introducing plug-and-play nanoelectromechanical systems (NEMS)

Posted: 11 Mar 2012 05:37 AM PDT

The measurement of very low concentrations of various agents plays an important role in medicine, pharmacology and food technology. So-called “nanomechanical resonators” – vibrating nanostrings – represent promising candidates for suitable detectors, because their oscillating motion is extremely sensitive to the binding of substances of interest. In recent years scientists have refined these techniques to the point where single atoms can now be detected. These analyses, however, have their shortcomings.

Exotic new matter expected in ultracold atoms

Posted: 10 Mar 2012 09:26 AM PST

Just as NASA engineers test new rocket designs in computer studies before committing themselves to full prototypes, so physicists will often model matter under various circumstances to see whether something new appears. This is especially true of atomtronics, a relatively new science devoted to creating artificial tailored materials consisting of neutral atoms held in an array with laser beams, or atoms moving along a desired track under electric or magnetic influence.

Maryland Study Urges Workplace Policies to Prevent Postpartum Depression, Save Costs

Posted: 10 Mar 2012 09:14 AM PST

Employed mothers who suffer postpartum depression incur higher overall health care costs, according to a study led by Dr. Rada K. Dagher, assistant professor of health services administration at the University of Maryland School of Public Health. Dr. Dagher suggests that employers should create programs to prevent and address postpartum mental health issues, as this could result in health care cost savings and a healthier workforce. The study is published in the Journal of Occupational and Environmental Medicine.

Gravitational lens reveals details of distant, ancient galaxy

Posted: 10 Mar 2012 08:34 AM PST

Thanks to the presence of a natural “zoom lens” in space, University of Chicago scientists working with NASA’s Hubble Space Telescope have obtained a uniquely close-up look at the brightest gravitationally magnified galaxy yet discovered.

Perceptions of Discrimination May Adversely Affect Health of Immigrants’ Children, Study Shows

Posted: 10 Mar 2012 08:27 AM PST

Children of recent immigrants are more likely to make sick visits to the doctor if their mothers see themselves as targets of ethnic or language-based discrimination, researchers at New York University report in a new study. Their research, which appears in the journal Health Psychology, provides new evidence that perceptions of discrimination by a mother could have a negative effect on the health of her child within the first 14 months of her child’s life.