Science News: It has been difficult to study the causes of deafness because the inner ear is well-protected by dense bone and is located near crucial blood vessels and nerves. Now Konstantina Stankovic of the Massachusetts Eye and Ear Infirmary in Boston and her colleagues have used two-photon microscopy to create detailed images of the inner ears of mice. For their study, they compared normal mice with mice that had been subjected to two hours of 160-dB sound—a level comparable to the roar of power tools. The resulting images provided clear pictures of the hair cells in the inner ear, which detect sound vibrations. In the mice subjected to the noise, whole areas of those cells had been destroyed. Stankovic hopes that the images created will help with the placement of cochlear implants, which can scrape and damage existing inner-ear hair cells. Stankovic’s group has also created a small, battery-like device that could power implants of various sorts and that would also benefit from the new placement technique.
Daily Archives: February 19, 2013
Coal’s cost is its own biggest enemy
Science: Since 2008, the amount of electricity generated by coal power plants in the US has dropped from 50% to 38%. More than 150 planned coal plant projects have been canceled since the mid 2000s. Only one new plant went on line in 2012. David Schlissel of the Institute for Energy Economics and Financial Analysis in Belmont, Massachusetts, has found that it’s the economics of the coal power industry that’s driving this precipitous drop. Construction and maintenance costs have increased rapidly. The plant that opened in 2012 was projected to cost $1.8 billion, but cost $4.9 billion by the time it was completed. And 60% of existing plants are more than 40 years old, so repairs and upgrades to make the plants more environmentally friendly often require extra work. Perhaps even more significant, however, is that the price of natural gas has dropped so much that companies that run coal plants have had to lower the price they charge for the electricity they generate. The result has been a drop in profits from $20 billion to just $4 billion from 2008 to 2011. Add in the rising cost of shipping coal and it’s clear, from an economic standpoint, that coal is no longer the best option for power generation.
Laser used to detect fake honey
Ars Technica: Because honey is an expensive food product, it has fallen prey to smuggling and counterfeiting: Honey snuck into the US from other countries, such as China, may be tainted with antibiotics or heavy metals, and some honey producers water down their product with corn or rice syrup, malt, or sugar. To separate the real from the fake, scientists are using laser technology developed to detect trace amounts of gas in outer space. Organic molecules contain a mix of carbon isotopes that show up in the molecules’ spectra. By burning a few milligrams of honey, investigators can use lasers to scan the carbon dioxide released and thereby determine the honey’s provenance. As the device is refined, it may also be used to test the health and safety of other food products, such as olive oil and chocolate.
Super nodes dominate network behavior
Nature: “The complex behaviour of a network can be fully captured by tracking a few crucial nodes,” writes Julie Rehmeyer for Nature. Researchers are developing mathematical techniques to study a wide range of natural, technological, and socioeconomic systems, ranging from the internet to the human body. To demonstrate their technique, Yang-Yu Liu of Northeastern University in Boston and colleagues studied the human metabolic network. They found that the levels of the body’s approximately 2700 metabolites could be calculated from just 10% of them. The researchers say the same technique could be used to predict political elections or follow changes in an ecosystem.