New material approach should increase solar cell efficiency

Apr. 23, 2013 ? "When designing next generation solar energy conversion systems, we must first develop ways to more efficiently utilize the solar spectrum," explained Lane Martin, whose research group has done just that.

"This is a fundamentally new way of approaching these matters," said Martin, who is an assistant professor of materials science and engineering (MatSE) at Illinois. "From these materials we can imagine carbon-neutral energy production of clean-burning fuels, waste water purification and remediation, and much more."

Martin's research group brought together aspects of condensed matter physics, semiconductor device engineering, and photochemistry to develop a new form of high-performance solar photocatalyst based on the combination of the TiO₂ (titanium dioxide) and other "metallic" oxides that greatly enhance the visible light absorption and promote more efficient utilization of the solar spectrum for energy applications.

Their paper appears in the journal Advanced Energy Materials.

According to Martin, the primary feature limiting the performance of oxide-based photovoltaic and/or photocatalytic systems has traditionally been the poor absorption of visible light in these often wide band gap materials. One candidate oxide material for such applications is anatase TiO₂, which is arguably the most widely-studied photocatalyst due to its chemical stability, non-toxicity, low-cost, and excellent band alignment to several oxidation-reduction reactions. As the backbone of dye-sensitized solar cells, however, the presence of a light-absorbing dye accounts for a large band gap which limits efficient usage of all but the UV portion of sunlight.

"We observed that the unusual electronic structure of SrRuO₃ is also responsible for unexpected optical properties including high absorption across the visible spectrum and low reflection compared to traditional metals," stated Sungki Lee, the paper's first author. "By coupling this material to TiO₂ we demonstrate enhanced visible light absorption and large photocatalytic activities."

"SrRuO₃ is a correlated electron oxide which is known to possess metallic-like temperature dependence of its resistivity and itinerant ferromagnetism and for its widespread utility as a conducting electrode in oxide heterostructures," Lee added. Referring to this material as a "metal," however, is likely inappropriate as the electronic structure and properties are derived from a combination of complex electronic density of states, electron correlations, and more.

Using a process called photo-excited hot-carrier injection from the SrRuO₃ to the TiO₂, the researchers created new heterostructures whose novel optical properties and the resulting high photoelectrochemical performance provide an interesting new approach that could advance the field of photocatalysis and further broaden the potential applications of other metallic oxides.

This work provides an exciting new approach to the challenge of designing visible-light photosensitive materials and has resulted in a provisional patent application. The work was primarily supported by the ongoing International Institute for Carbon Neutral Energy Research (I²CNER) program, a partnership between Kyushu University in Japan and the University of Illinois.

"The I²CNER project brings together some of the leading energy researchers from around the globe," explained I²CNER Director Petros Sofronis, who is also a professor in the Department of Mechanical Science and Engineering at Illinois. "Results from Dr. Martin's research group and others demonstrate that I²CNER is not only an experiment on international collaboration. It is a concerted institutionalized effort to pursue green innovation and reduced CO₂ emissions, as well as to advance fundamental science and develop science-based technological solutions for the reorganization of sustainable and environmentally friendly society."

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The above story is reprinted from materials provided by University of Illinois College of Engineering. The original article was written by Rick Kubetz.

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Journal Reference:

1. Sungki Lee, Brent A. Apgar, Lane W. Martin. Strong Visible-Light Absorption and Hot-Carrier Injection in TiO2/SrRuO3Heterostructures. Advanced Energy Materials, 2013; DOI: 10.1002/aenm.201201116

Note: If no author is given, the source is cited instead.

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Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/top_technology/~3/T_2AUjCLfdU/130423135839.htm

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Whether human or hyena, there' s safety in numbers

Apr. 23, 2013 ? Humans, when alone, see threats as closer than they actually are. But mix in people from a close group, and that misperception disappears.

In other words, there's safety in numbers, according to a new study by two Michigan State University scholars. Their research provides the first evidence that people's visual biases change when surrounded by members of their own group.

"Having one's group or posse around actually changes the perceived seriousness of the threat," said Joseph Cesario, lead author on the study and assistant professor of psychology. "In that situation, they don't see the threat quite so closely because they have their people around to support them in responding to the threat.'"

Funded by the National Science Foundation, the study appears online in the journal Social Psychological and Personality Science.

The study was inspired by MSU zoologist Kay Holekamp's research with wild hyenas in Kenya. Holekamp and her team played recordings of hyenas from other parts of Africa and found the hyenas listening to the voices were more likely to approach the source of the sound when they were in groups and more likely to flee when they were alone.

The research by Cesario and Carlos Navarrete, associate professor of psychology, was similar, only it dealt with humans and perceived distance of potential threats. In two separate studies of more than 300 participants, the researchers showed that people who are alone judge threats as much closer than when they are in a group.

Like most social species, hyenas and humans have developed adaptations over time to better deal with predatory threats.

"This is about evolutionarily significant threats, such as members of a different group coming to steal resources or attack you," Cesario said. "The cost of not responding soon enough to a threat like that could be death or serious injury. So seeing that threat as closer allows you to respond with enough time to spare. What our work shows is that having your group or coalition around you makes that kind of early responding less necessary."

The study dealt with racial bias and group threats. The participants, who were white, were assessed on how negative they were toward blacks and then asked to judge the distance to a black community, both when the participants were alone and as part of a group.

Cesario said the perceived threat can take many forms -- be it from other races, communities or even students from another university, as one nonrelated study showed.

"So this line of research has little to do with the makeup of the group -- whether it's members of another race or students from another college -- but more to do with the question of, 'Are you with me or not?'"

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Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/top_environment/~3/MXBVh0gi7Lw/130423135115.htm

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Battling with bugs to prevent antibiotic resistance

Apr. 23, 2013 ? New scientific research published today in the journal PLoS Biology shows that bacteria can evolve resistance more quickly when stronger antibiotics are used.

Researchers from the University of Exeter and Kiel University in Germany treated E. coli with different combinations of antibiotics in laboratory experiments.

Unexpectedly they found that the rate of evolution of antibiotic resistance speeds up when potent treatments are given because resistant bacterial cells flourish most during the most aggressive therapies.

This happens because too potent a treatment eliminates the non-resistant cells, creating a lack of competition that allows resistant bacteria to multiply quickly. Those cells go on to create copies of resistance genes that help them rapidly reduce the effectiveness of the drugs. In tests this effect could even cause E.coli to grow fastest in the most aggressive antibiotic treatments.

In addition to evolution experiments, the results of this Engineering and Physical Sciences Research Council (EPSRC) and Medical Research Council (MRC) funded research were confirmed using mathematical models and whole-genome sequencing of resistant and non-resistant E. coli.

Professor Robert Beardmore, EPSRC Research Fellow from the University of Exeter said: "We were surprised by how quickly the bacteria evolved resistance. We nearly stopped the experiments because we didn't think some of the treatments should be losing potency that fast, sometimes within a day. But we now know that the bacteria remaining after the initial treatment have duplicated specific areas of their genome containing large numbers of resistance genes. These gene copies appear more quickly when the antibiotics are combined, resulting in the rapid evolution of very resistant bacteria.

"Designing new treatments to prevent antibiotic resistance is not easy, as this research shows, and governments may need to increase their funding for antibiotics research if scientists are to be able to keep pace with the rapid evolution of bacterial pathogens that cause disease."

Dr Rafael Pena-Miller from Biosciences at the University of Exeter said: "The evidence that combining antibiotics to make a more potent therapy can lead to the creation of more copies of the genes the bacteria needs to be resistant is of real concern."

Professor Hinrich Schulenberg from Kiel University in Germany said: "The interesting thing is that the bacteria don't just make copies of the genes they need. Just in case, they copy other genes as well, increasing resistance to antibiotics the cells weren't even treated with."

About 440 000 new cases of drug-resistant tuberculosis emerge annually, causing around 150 000 deaths. Statistics like this recently lead the Department of Health to state that antibiotic resistance poses one of the greatest threats to human health.

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Source: http://feeds.sciencedaily.com/~r/sciencedaily/health_medicine/genes/~3/zprA_T5Qf9w/130423172704.htm

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Farrah Abraham: DESTROYED By Dr. Phil in Awesome Interview

Source: http://www.thehollywoodgossip.com/2013/04/farrah-abraham-destroyed-by-dr-phil-in-awesome-interview/

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Philadelphia considering 2024 Olympics bid, mayor says

By Jonathan Allen

(Reuters) - Philadelphia is exploring a bid to host the 2024 Olympic Games, Mayor Michael Nutter said on Monday.

Nutter was responding to a letter from the United States Olympic Committee (USOC) sent to 35 cities across the country seeking potential host cities for the international sporting event.

"The Philadelphia region has enthusiastically embraced the prospect of bidding on and hosting a future Olympic Games, and we look forward with great anticipation to the opportunity to work with the USOC on this project," Nutter said in a statement.

USOC will decide over the next two years whether to submit a bid to host the 2024 games in the United States. If it goes ahead, it will submit the candidate city for consideration by the International Olympic Committee, the organizer of the games, in Lausanne, Switzerland.

The last time the United States hosted the Olympics was in 1996 in Atlanta.

(Reporting by Jonathan Allen; Editing by Cynthia Johnston and Vicki Allen)

Source: http://news.yahoo.com/philadelphia-considering-2024-olympics-bid-mayor-says-003439058--oly.html

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British comedian Dawn French marries for a second time

LONDON (Reuters) - British comedian Dawn French, who plays "The Vicar of Dibley" in the award-winning television comedy, has married for the second time, her publicist said on Monday.

French, 55, married charity worker Mark Bignell at the Scarlett Hotel near Newquay in Cornwall, south west England, on Saturday. The hotel describes itself as a luxury, eco venue overlooking the ocean.

Her first marriage, to comedian Lenny Henry, ended in 2010 after 25 years. The pair have an adopted daughter, Billie.

Besides the Emmy-winning "Vicar of Dibley", French is best known for her comedy collaboration with Jennifer Saunders in the popular long-running BBC comedy "French & Saunders".

Bignell is the chief executive of Hamoaze House which helps recovering drug and alcohol abusers reintegrate into society.

(Reporting by Belinda Goldsmith, editing by Paul Casciato)

Source: http://news.yahoo.com/british-comedian-dawn-french-marries-second-time-142835040.html

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Louisiana has nation's highest auto insurance rates - again - WWL-TV

Chance Ryan / Houma Courier

Louisiana's auto insurance rates remain the highest in the nation, according to industry studies.

A March report from Insure.com, an insurance industry website, shows Louisiana's average auto insurance rates at $2,699 annually, followed by Michigan at $2,520 and Georgia at $2,155.

By comparison, the national average for car insurance premiums in the U.S. is a little more than $1,500.

This is the third year in a row Louisiana tops the list. Before 2011 it held the No. 2 spot for years, industry reports show.

Maine enjoys the least expensive car insurance rates, at $934 per year, followed by Iowa, $1,028.

A variety of factors dictate how costly auto insurance will be state by state, the report says. Such as the number of insurers competing for business, driving conditions, the portion of uninsured drivers and the way state insurance systems are set up.

Compared to the rest of the country, the study notes that Louisiana drivers who get in wrecks file more injury claims than motorists in other states.

Louisiana also has a high rate of natural disaster damage.

Blue Bunol, general manager for ABC Insurance, a local auto insurance agency with 62 locations throughout Louisiana and Texas, said the litigious nature of people in the state make it difficult for insurance companies to keep costs low.

Louisiana faces issues with high insurance costs because of poor roads and natural disasters, Bunol said. But it's also the personal injury lawyers who advertise heavily on television and on bus stop benches, and the state's direct-action law, which allows people to sue insurers directly.

Louisiana is ranked 13th in the country for attorneys per capita, with 11.1 lawyers per 10,000 residents, according to AveryIndex.com, a law and rankings website.

The state's relatively poor population sees this aggressive advertising, Bunol said, many of which (about 13 percent) don't have car insurance and are more inclined to wring whatever they can out of an insurance policy.

?Attorney advertisement entices people who are looking for a handout to call whether their accident warrants it or not,? he said. ?Then the attorneys build a claim around nothing. Many of these claims are turning into a feeding frenzy.?

Louisiana has the highest frequency of bodily injury claims, according to a report by the Insurance Research Council.

Bunol said drivers can still get good deals if they rely more on insurers, like ABC, who offer mixed packages that drive competition.

He also noted that high car insurance rates are not necessarily statewide. The highest rates are largely concentrated in the New Orleans metropolitan area.

For example, a 21-year-old male with a clean driving record who drives a 2005 Toyota Corolla pays $246.05 per month for basic insurance in New Orleans, according to ABC quotes. Using that same sample, the monthly cost would be only $176.54 in Houma.

Bunol said another factor that contributes to the high costs is the high level of alcohol consumption in Louisiana.

?You don't have many states where you can drive though a daiquiri place and get a highball and a beer to go,? he said.

Deplorable road conditions, as a result of the soft nature of the soil, contribute to the costs as well, he said.

?So you got poor streets and more people drinking and driving ? yeah, that's going to increase the frequency of claims.?

Melissa Landry, director of Louisiana Lawsuit Abuse Watch, a nonprofit judicial-reform organization based in Baton Rouge, said a unique law in Louisiana, which dictates that civil claims under $50,000 must be decided by a judge, not a jury, is unfair to residents and insurance companies.

It puts more power into the hands of elected judges, Landry alleges. And that may encourage some contingency fee attorneys who make a living based on court outcomes to seek out judges who have a track record of siding with plaintiffs ? the people living in the communities they serve ? more than insurers they sue.

While Landry does not want to paint the judiciary with a broad brush, she said it's clear that money contributed to judicial elections may at times add an element of political pressure that juries don't experience.

?In recent analysis of civil jury trial threshold limits for all 50 states, Louisiana Lawsuit Abuse Watch found that the vast majority of states have no threshold for civil jury trials, and among 14 states that do, Louisiana's threshold is by far the highest in the nation,? Landry said. ?At $50,000, Louisiana's jury trial threshold is roughly more than 28 times the national average of $1,742.40.?

The $50,000 threshold was enacted during the last administration of former Gov. Edwin Edwards in 1993 in an effort by legislators to prevent overburdening the courts with more bureaucracy and increased government spending for assembling juries and other costs.

In various reports, legislators have said people who come for jury duty do not want to waste time for minor traffic claims. And if the trial threshold were to be lowered, even more civil jury trials will take place, which will create longer delays in an already backed-up judiciary system.

?It is unfair to ask the citizens of Louisiana to serve on juries for small claims that can be effectively and efficiently handled by judges ? and have been for years,? Michael L. Barras, a personal injury attorney in New Iberia, wrote on his website.

Bunol said the truth is insurance companies don't really care how high the rates go nor do legislators because it all evens out in the end.

?They look at it as another form of welfare,? Bunol said. ?Instead of tax dollars distributed as welfare, it's insurance dollars that are simply paid by the public anyway ? same as tax dollars. Insurance companies are going to pay the claim and ultimately change their rate accordingly. But all of us who pay high insurance rates should be screaming at the legislators to make stiffer laws to keep these attorneys from being able to build up a claim that should have never existed in the first place.?

Source: http://www.wwltv.com/news/local/Louisiana-has-nations-highest-auto-insurance-rates---again-203984451.html

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