PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Research shows radiometric dating still reliable (again)

2010-09-16
(Press-News.org) Recent puzzling observations of tiny variations in nuclear decay rates have led some to question the science of using decay rates to determine the relative ages of rocks and organic materials. Scientists from the National Institute of Standards and Technology (NIST), working with researchers from Purdue University, the University of Tennessee, Oak Ridge National Laboratory and Wabash College, tested the hypothesis that solar radiation might affect the rate at which radioactive elements decay and found no detectable effect.

Atoms of radioactive isotopes are unstable and decay over time by shooting off particles at a fixed rate, transmuting the material into a more stable substance. For instance, half the mass of carbon-14, an unstable isotope of carbon, will decay into nitrogen-14 over a period of 5,730 years. The unswerving regularity of this decay allows scientists to determine the age of extremely old organic materials—such as remains of Paleolithic campfires—with a fair degree of precision. The decay of uranium-238, which has a half-life of nearly 4.5 billion years, enabled geologists to determine the age of the Earth.

Many scientists, including Marie and Pierre Curie, Ernest Rutherford and George de Hevesy, have attempted to influence the rate of radioactive decay by radically changing the pressure, temperature, magnetic field, acceleration, or radiation environment of the source. No experiment to date has detected any change in rates of decay.

Recently, however, researchers at Purdue University observed a small (a fraction of a percent), transitory deviation in radioactive decay at the time of a huge solar flare. Data from laboratories in New York and Germany also have shown similarly tiny deviations over the course of a year. This has led some to suggest that Earth's distance from the sun, which varies during the year and affects the planet's exposure to solar neutrinos, might be related to these anomalies.

Researchers from NIST and Purdue tested this by comparing radioactive gold-198 in two shapes, spheres and thin foils, with the same mass and activity. Gold-198 releases neutrinos as it decays. The team reasoned that if neutrinos are affecting the decay rate, the atoms in the spheres should decay more slowly than the atoms in the foil because the neutrinos emitted by the atoms in the spheres would have a greater chance of interacting with their neighboring atoms. The maximum neutrino flux in the sample in their experiments was several times greater than the flux of neutrinos from the sun. The researchers followed the gamma-ray emission rate of each source for several weeks and found no difference between the decay rate of the spheres and the corresponding foils.

According to NIST scientist emeritus Richard Lindstrom, the variations observed in other experiments may have been due to environmental conditions interfering with the instruments themselves.

"There are always more unknowns in your measurements than you can think of," Lindstrom says.

###* R.M. Lindstrom, E. Fischbach, J.B. Buncher, G.L. Greene, J.H. Jenkins, D.E. Krause, J.J. Mattes and A. Yue. Study of the dependence of 198Au half-life on source geometry. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. doi:10.1016/j.nima.2010.06.270

END



ELSE PRESS RELEASES FROM THIS DATE:

Children's brain development is linked to physical fitness

Childrens brain development is linked to physical fitness
2010-09-16
CHAMPAIGN, lll. – Researchers have found an association between physical fitness and the brain in 9- and 10-year-old children: Those who are more fit tend to have a bigger hippocampus and perform better on a test of memory than their less-fit peers. The new study, which used magnetic resonance imaging to measure the relative size of specific structures in the brains of 49 child subjects, appears in the journal Brain Research. "This is the first study I know of that has used MRI measures to look at differences in brain between kids who are fit and kids who aren't fit," ...

NIST data: Enabling the technical-basis for evacuation planning of high-rise buildings

2010-09-16
Researchers at the National Institute of Standards and Technology (NIST) are stepping up the pace for designing safer building evacuations by releasing large, numerical data sets that track the movement of people on stairs during high-rise building evacuation drills. The data sets will ensure that architects, engineers, emergency planners and others involved in building design have a strong technical basis for safer, more cost-effective building evacuations. "While stairs have been used in buildings for ages, there is little scientific understanding of how people use ...

New GSI website experience puts product standards on the map

2010-09-16
Those looking for the latest product standards-related news, regulatory developments, events and workshops around the world now can turn to the new Global Standards Information (GSI) Web site (http://gsi.nist.gov). Launched on Sept. 1, 2010, the new site includes a variety of interactive tools and will serve as an essential "first stop" for users seeking up-to-date information on international product standards. "Given the rapid adoption and complexity of new product standards both locally and globally, we realized we needed to create a new way for our customers to find ...

NIST finalizes initial set of smart grid cyber security guidelines

2010-09-16
The National Institute of Standards and Technology (NIST) has issued its first Guidelines for Smart Grid Cyber Security, which includes high-level security requirements, a framework for assessing risks, an evaluation of privacy issues at personal residences, and additional information for businesses and organizations to use as they craft strategies to protect the modernizing power grid from attacks, malicious code, cascading errors and other threats. The product of two formal public reviews and the focus of numerous workshops and teleconferences over the past 17 months, ...

New supercomputer 'sees' well enough to drive a car someday

New supercomputer sees well enough to drive a car someday
2010-09-16
New Haven, Conn.—Navigating our way down the street is something most of us take for granted; we seem to recognize cars, other people, trees and lampposts instantaneously and without much thought. In fact, visually interpreting our environment as quickly as we do is an astonishing feat requiring an enormous number of computations—which is just one reason that coming up with a computer-driven system that can mimic the human brain in visually recognizing objects has proven so difficult. Now Eugenio Culurciello of Yale's School of Engineering & Applied Science has developed ...

Placebo successful in treating women with sexual dysfunction

2010-09-16
A new study published in the Journal of Sexual Medicine reveals that women with low sexual arousal experienced clinically significant symptom changes after taking a placebo. Andrea Bradford, Ph.D., a psychologist at Baylor College of Medicine, along with co-author Cindy Meston, Ph.D. at the University of Texas at Austin, analyzed the behaviors and symptoms of 50 women who were randomly chosen to receive placebo in a large clinical trial of a drug treatment for low sexual arousal. Neither the women nor the study doctors knew whether they were taking the real drug or placebo. Results ...

CEOs with top college degrees no better at improving long-term firm performance than other CEOs

2010-09-16
DURHAM, N.H. – Whether or not a company's CEO holds a college degree from a top school has no bearing on the firm's long-term performance. And when it comes to getting canned for poor performance, CEOs with degrees from the nation's most prestigious schools are no safer than the average CEO, according to new research from the University of New Hampshire. Conducted by Brian Bolton, assistant professor of finance at the Whittemore School of Business and Economics at the University of New Hampshire, the new research is presented in the working paper "CEO Education, CEO Turnover, ...

Link to autism in boys found in missing DNA

2010-09-16
September 16, 2010 – (Toronto) – New research from the Centre for Addiction and Mental Health (CAMH) and The Hospital for Sick Children (SickKids), both in Toronto, Canada provides further clues as to why Autism Spectrum Disorder (ASD) affects four times more males than females. The scientists discovered that males who carry specific alterations of DNA on the sole X-chromosome they carry are at high risk of developing ASD. The research is published in the September 15 issue of Science Translational Medicine. ASD is a neurological disorder that affects brain functioning, ...

Chef Point's 'Acquired Taste' Menu - A Walk on the Wild Side

Chef Points Acquired Taste Menu - A Walk on the Wild Side
2010-09-16
Oxtail, marinated in homemade spicy African seasoning, slowly cooked it until it falls off the bone. Where can you enjoy this delicious delicacy and other hard-to-find dishes? Only during a unique fine dining experience at Chef Point Cafe. Franson Nwaeze, the head chef at Chef Point Cafe, has never been afraid to try something new. He is giving curious diners the opportunity to take a walk on the wild side with his new, one-of-a-kind "Acquired Taste" Menu. The most popular dish on the special menu has been Liver and Onions. The dish of beef liver sauteed with mushrooms, ...

CiCi's Pizza Targets 500-Store Expansion Over the Next Six Years

2010-09-16
CiCi's Pizza, home of the $4.99 endless pizza, pasta, salad and dessert buffet, announces today its plans to add 500 restaurants in the next five to six years. "Our 'One Brand' mission is well underway, ensuring we have a repeatable approach to operations that gives guests across the country a consistent, high-quality experience with every visit," said Mike Shumsky, CiCi's Pizza CEO. "Our team of industry leaders will take CiCi's to the next level and grow the company." CiCi's has hired two industry veterans Bill Spae and Nancy Hampton to drive the expansion of the ...

LAST 30 PRESS RELEASES:

Reality check: making indoor smartphone-based augmented reality work

Overthinking what you said? It’s your ‘lizard brain’ talking to newer, advanced parts of your brain

Black men — including transit workers — are targets for aggression on public transportation, study shows

Troubling spike in severe pregnancy-related complications for all ages in Illinois

Alcohol use identified by UTHealth Houston researchers as most common predictor of escalated cannabis vaping among youths in Texas

Need a landing pad for helicopter parenting? Frame tasks as learning

New MUSC Hollings Cancer Center research shows how Golgi stress affects T-cells' tumor-fighting ability

#16to365: New resources for year-round activism to end gender-based violence and strengthen bodily autonomy for all

Earliest fish-trapping facility in Central America discovered in Maya lowlands

São Paulo to host School on Disordered Systems

New insights into sleep uncover key mechanisms related to cognitive function

USC announces strategic collaboration with Autobahn Labs to accelerate drug discovery

Detroit health professionals urge the community to act and address the dangers of antimicrobial resistance

3D-printing advance mitigates three defects simultaneously for failure-free metal parts 

Ancient hot water on Mars points to habitable past: Curtin study

In Patagonia, more snow could protect glaciers from melt — but only if we curb greenhouse gas emissions soon

Simplicity is key to understanding and achieving goals

Caste differentiation in ants

Nutrition that aligns with guidelines during pregnancy may be associated with better infant growth outcomes, NIH study finds

New technology points to unexpected uses for snoRNA

Racial and ethnic variation in survival in early-onset colorectal cancer

Disparities by race and urbanicity in online health care facility reviews

Exploring factors affecting workers' acquisition of exercise habits using machine learning approaches

Nano-patterned copper oxide sensor for ultra-low hydrogen detection

Maintaining bridge safer; Digital sensing-based monitoring system

A novel approach for the composition design of high-entropy fluorite oxides with low thermal conductivity

A groundbreaking new approach to treating chronic abdominal pain

ECOG-ACRIN appoints seven researchers to scientific committee leadership positions

New model of neuronal circuit provides insight on eye movement

Cooking up a breakthrough: Penn engineers refine lipid nanoparticles for better mRNA therapies

[Press-News.org] Research shows radiometric dating still reliable (again)