Paper could be basis for inexpensive diagnostic devices

May 29, 2013 ? Paper is known for its ability to absorb liquids, making it ideal for products such as paper towels. But by modifying the underlying network of cellulose fibers, etching off surface "fluff" and applying a thin chemical coating, researchers have created a new type of paper that repels a wide variety of liquids -- including water and oil.

The paper takes advantage of the so-called "lotus effect" -- used by leaves of the lotus plant -- to repel liquids through the creation of surface patterns at two different size scales and the application of a chemical coating. The material, developed at the Georgia Institute of Technology, uses nanometer- and micron-scale structures, plus a surface fluorocarbon, to turn old-fashioned paper into an advanced material.

The modified paper could be used as the foundation for a new generation of inexpensive biomedical diagnostics in which liquid samples would flow along patterns printed on the paper using special hydrophobic ink and an ordinary desktop printer. This paper could also provide an improved packaging material that would be less expensive than other oil- and water-repelling materials, while being both recyclable and sustainable.

"Paper is a very heterogeneous material composed of fibers with different sizes, different lengths and a non-circular cross-section," said Dennis Hess, a professor in the Georgia Tech School of Chemical and Biomolecular Engineering. "We believe this is the first time that a superamphiphobic surface -- one that repels all fluids -- has been created on a flexible, traditional and heterogeneous material like paper."

Research leading to development of the superamphiphobic paper has been supported by the Institute for Paper Science and Technology (IPST) at Georgia Tech. Details were published online May 24 in the journal ACS Applied Materials & Interfaces.

The new paper, which is both superhydrophobic (water-repelling) and super oleophobic (oil-repelling), can be made from standard softwood and hardwood fibers using a modified paper process. In addition to Hess, the research team included Lester Li, a graduate research assistant, and Victor Breedveld, an associate professor in the School of Chemical and Biomolecular Engineering

Producing the new paper begins with breaking up cellulose fibers into smaller structures using a mechanical grinding process. As in traditional paper processing, the fibers are then pressed in the presence of water -- but then the water is removed and additional processing is done with the chemical butanol. Use of butanol inhibits the hydrogen bonding that normally takes place between cellulose fibers, allowing better control of their spacing.

"The desirable properties we are seeking are mainly controlled by the geometry of the fibers," Hess explained.

The second step involves using an oxygen plasma etching process -- a technique commonly used in the microelectronics industry -- to remove the layer of amorphous "fluffy" cellulose surface material, exposing the crystalline cellulose nanofibrils. The process thereby uncovers smaller cellulose structures and provides a second level of "roughness" with the proper geometry needed to repel liquids.

Finally, a thin coating of a fluoropolymer is applied over the network of cellulose fibers. In testing, the paper was able to repel water, motor oil, ethylene glycol and n-hexadecane solvent.

The researchers have printed patterns onto their paper using a hydrophobic ink and a desktop printer. Droplets applied to the pattern remain on the ink pattern, repelled by the adjacent superamphiphobic surface.

That capability could facilitate development of inexpensive biomedical diagnostic tests in which a droplet containing antigens could be rolled along a printed surface where it would encounter diagnostic chemicals. If appropriate reagents are used, the specific color or color intensity of the patterns could indicate the presence of a disease. Because the droplets adhere tightly to the printed lines or dots, the samples can be sent to a laboratory for additional testing.

"We have shown that we can do the operations necessary for a microfluidic device," Hess said. "We can move the droplet along a pattern, split the droplet and transfer the droplet from one piece of paper to another. We can do all of these operations on a two-dimensional surface."

For Hess, Li and Breedveld, creating a superhydrophobic suface was relatively straightforward because water has a high surface tension. For oils, which have a low surface tension, the key to creating the repellent surface is to create re-entrant -- or undercut -- angles between the droplets and the surface.

Previous examples of superamphiphobic surfaces have been made on rigid surfaces through lithographic techniques. Such processes tend to produce fragile surfaces that are prone to damage, Hess said.

The principal challenge has been to create high-performance in a material that is anything but geometrically regular and consistent.

"Working with heterogeneous materials is fascinating, but it's very difficult not just to control them, because there is no inherent consistent structure, but also to change the processing conditions so you can get something that, on average, is what you need," he said. "It's been a real learning experience for us."

The new paper has so far been made in samples about four inches on a side, but Hess sees no reason why the process couldn't be scaled up. Though long-term testing of the new paper hasn't been done, Hess is encouraged by what he's seen so far.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/top_health/~3/Ttm60UKrBKA/130529092053.htm

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Good for the world, good for shareholders: Study finds social responsibility means less risky stock prices

May 28, 2013 ? Firms that make greater investments in corporate social responsibility (CSR) initiatives see less risk in their stock prices during economic downturns, according to a new study from the University of Iowa.

The research, by Art Durnev, assistant professor of finance in the Tippie College of Business, suggests that those companies have greater brand loyalty, so customers keep buying their products and paying a premium for them, regardless of the overall economy. That stability in turn reduces those firms' costs of equity capital, further reducing its overall risk.

CSR has become an increasingly important part of business in recent years, as more customers look to buy from companies with practices that match their own values, especially when it comes to environmental issues. While research has shown that companies like Patagonia and Ben & Jerry's have increased brand loyalty because of their extensive CSR initiatives, Durnev says little research has been done to see how that loyalty affects firms' stock prices.

"CSR's increased popularity inside boardrooms has outpaced the research needed to justify it," Durnev says. "Many questions still remain on how CSR policies affect the risks firms are facing and the stock market implications of those policies."

In their paper, Durnev and his co-authors try to find those affects by looking at the stock prices of 3,005 firms from 34 countries between 2004 and 2010. The prices were from a database that factored in the social and environmental risk factors of each company, among them: labor relations, health and safety, recruitment and retention strategies, progressive workplace practices, and environmental and climate risk. In the end, the researchers drew from 9,795 firm year observations.

The researchers tabulated a CSR score for industries of between 1 and 10, with software companies having the highest scores of 7.031. Textiles and apparel were second at 6.717, and leisure equipment and products at 6.215.

The industries with the lowest CSR score were chemicals at 2.511, insurance at 3.120, and broadcast and cable TV at 3.324.

The researchers found the level of risk was significantly lower for firms with higher CSR scores, especially during economic downturns, as loyal customers kept sales higher during hard times than firms that did not practice CSR initiatives. That revenue and stock price stability led to lower equity costs, reducing firm risk further and making the stock even more attractive to buyers.

The study also finds that timing is important, as the first firm to start using CSR practices in an industry gets a larger market share, leaving less for its competitors that adopt CSR later on.

"The second entrant into the market doesn't get as many customers as the industry leader so there's less benefit, and so on," he says. Eventually, Durnev says latecomers have no incentive to start using CSR practices because its competitors have taken up so much of the market there's nothing left for them. The risk of adopting CSR, he says, is no longer worth the investment.

The study, Corporate Social Responsibility and Asset Pricing in Industry Equilibrium, was co-authored by Rui Albequerque and Yrjo Koskinen of Boston University. It received the best paper award at the first Geneva Summit on Sustainable Finance in March and will be presented in June at the Symposium on Sustainability & Finance organized by the California Public Employees Retirement System and the University of California at Davis.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/~3/KBBwiqk5gno/130528180850.htm

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Fast start for Serena Williams at French Open

Serena Williams of the U.S. prepares to serve against Georgia's Anna Tatishvili in their first round match of the French Open tennis tournament, at Roland Garros stadium in Paris, Sunday, May 26, 2013. (AP Photo/Petr David Josek)

Serena Williams of the U.S. prepares to serve against Georgia's Anna Tatishvili in their first round match of the French Open tennis tournament, at Roland Garros stadium in Paris, Sunday, May 26, 2013. (AP Photo/Petr David Josek)

Switzerland's Roger Federer returns against Spain's Pablo Carreno Busto in their first round match of the French Open tennis tournament, at Roland Garros stadium in Paris, Sunday, May 26, 2013. (AP Photo/Petr David Josek)

USA's Sam Querrey returns the ball to Slovakia's Lukas Lacko during their first round match of the French Open tennis tournament at the Roland Garros stadium Sunday, May 26, 2013 in Paris. (AP Photo/Christophe Ena)

Serena Williams, of the USA, serves the ball to Georgia's Anna Tatishvili during their first round match of the French Open tennis tournament at the Roland Garros stadium Sunday, May 26, 2013 in Paris. (AP Photo/Petr David Josek)

Serena Williams, of the USA, returns the ball to Georgia's Anna Tatishvili during their first round match of the French Open tennis tournament at the Roland Garros stadium Sunday, May 26, 2013 in Paris. (AP Photo/Petr David Josek)

PARIS (AP) ? Serena Williams won her opening match at the French Open, and then achieved a career breakthrough by speaking French to the crowd for the first time.

"I'm a beginner," Williams said ? referring to her French, not tennis.

Her play spoke volumes Sunday. Williams returned to the red clay that tripped her up in the first round a year ago, channeled any lingering frustration into her overpowering strokes and ? voila ? drubbed Anna Tatishvili 6-0, 6-1.

Roger Federer, the 2009 champion, remained unbeaten in first-round matches at major tournaments since 2003 by sweeping qualifier Pablo Carreno Busta 6-2, 6-2, 6-3. Sam Querrey, the highest-ranked American on the men's tour, equaled his best showing at Roland Garros by reaching the second round when he beat Lukas Lacko 6-3, 6-4, 6-4.

Williams lost her opening match at a Grand Slam tournament for the only time in her career a year ago, when she was beaten by France's Virginie Razzano. That was the most shocking in a succession of losses for Williams at Roland Garros, where she hasn't won the title since 2002 and hasn't reached the semifinals since 2003.

"I just keep trying, and it hasn't been working out for me," she said. "I may have gotten nervous in the past or may have basically choked a few matches away. Some matches I just lost because maybe I wasn't intense enough, or maybe I didn't do enough work before I got here."

Determined to avoid another bad start, Williams won the first nine games against Tatishvili, and 30 of the first 37 points. There was no letup from there, and she was still pumping her fist and shouting "Come on!" a game from the finish.

The No. 1-ranked Williams won 56 of 78 points, including 28 of 33 on her serve, and hit eight aces. She extended her winning streak to 25 consecutive matches, and since the loss to Razzano, she's 68-3, including championships at Wimbledon and the U.S. Open.

Beginning her bid for a 16th Grand Slam title, Williams maintained a stern expression throughout the match, and allowed herself only a brief smile when Tatishvili pushed a forehand wide on match point.

Williams, who keeps an apartment in Paris, was then interviewed on center court and spoke French with only a slight accent.

"I have been speaking French for years and years, but I don't really have a lot of confidence," she said later in English. "It's way, way more nerve-racking than playing tennis."

Federer also spoke French to the crowd, and also won easily. He lost only seven points on his first serve and was broken just once by Carreno Busta, a 21-year-old Spaniard was making his Grand Slam debut after winning seven consecutive Futures events.

"He has played a lot of matches on clay in comparison with me," Federer said. "I knew it could be tricky if I don't sustain a certain level of play and certain aggressiveness and get caught up maybe in long rallies, maybe what he's looking for. Overall I thought I did well."

Others advancing on a chilly, gray first day of play included Sara Errani, the 2012 runner-up to Maria Sharapova, and 2008 champion Ana Ivanovic.

American Mallory Burdette, whose ranking has climbed to a career-best 80th from 142nd at the start of the year, made a successful Roland Garros debut by beating Donna Vekic 6-3, 6-4.

Burdette, a 22-year-old Stanford alum, said she has enjoyed learning how to play on clay.

"It's a bit of a challenge," she said. "You have to change up your strategy a little bit, especially if you're a big hitter. It takes a little bit of effort, but it's fun."

Dominant serving helped Querrey advance. He had been eliminated the first round at Roland Garros five times, and his only previous victory in the tournament came in 2011 on remote Court 7, where he played again Sunday.

"That's the only court I can win on here," he said with a smile. "I played the best match I've played all year on any surface."

Former No. 1 Lleyton Hewitt lost a seesaw marathon to No. 15-seeded Gilles Simon, 3-6, 1-6, 6-4, 6-1, 7-5. No. 4 David Ferrer, a semifinalist last year, eliminated Marinko Matosevic 6-4, 6-3, 6-4.

An hour into the tournament, Errani was into the second round. The tenacious Italian beat Arantxa Rus 6-1, 6-2 in the opening match on Court Suzanne Lenglen.

Errani reached a Grand Slam final for the first time a year ago at Roland Garros.

"Last year was an unbelievable tournament, the best tournament of my life," Errani said. "But I don't want to think about that. I just want to come here and play another tournament. I try to concentrate on my tennis, not too much about last year."

Now ranked a career-best No. 5, Errani dominated Rus from the baseline and won four games at love. Rus double-faulted seven times and lost her 13th consecutive match on the WTA Tour.

Ivanovic, seeded 14th, beat Petra Martic 6-1, 3-6, 6-3. Ivanovic improved to 30-4 in the first round of Grand Slam tournaments.

Associated Press

Source: http://hosted2.ap.org/APDEFAULT/347875155d53465d95cec892aeb06419/Article_2013-05-26-TEN-French-Open/id-617735c9e0fe441bbb8740b87c30294f

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Search scaled back for abducted Iowa teenage girl

DAYTON, Iowa (AP) ? Authorities are scaling back their search for a missing Iowa teenager abducted from a rural school bus stop this week.

The state Department of Public Safety says trained law enforcement will narrow their search around Dayton on Saturday for 15-year-old Kathlynn Shepard.

Authorities say they're focusing on terrain that's difficult to navigate and requires specialized skills and equipment, so citizen volunteers are not needed. Residents are encouraged to check their rural properties for anything suspicious.

Police suspect Michael Klunder took Kathlynn and a 12-year-old girl on Monday to a hog confinement building several miles away. The younger girl managed to escape. Klunder was later found dead of self-inflicted injuries.

Authorities will search land between the hog confinement and a location where the girls' backpacks were found.

Source: http://news.yahoo.com/officials-scale-back-search-abducted-iowa-teen-234216630.html

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Morgan Freeman falls asleep on live TV

Celebs

Gael Fashingbauer Cooper TODAY

20 hours ago

Zzzzz... Look, film promotion can be an exhausting business. And who can blame an esteemed actor like Morgan Freeman if he gets tired of doing the same kind of local-news interview to promote his new movie in dozens of cities? Freeman and Michael Caine spoke to Seattle's Fox affiliate, Q13, via satellite from New York on Wednesday, and it looked as if Freeman grabbed a little shut-eye while Caine was talking.

Q13 FOX

Did Morgan Freeman catch a nap during a live interview with Seattle news station Q13?

The two actors were promoting their new film, "Now You See Me," a thriller about bank robbers who use magic, in an interview with anchors Kaci Aitchison and Bill Wixey.

When addressed directly, Freeman, 75, gamely discussed the film and even gave Wixey advice on being a narrator for the anchor's young daughter, who has such a role in her school play. (The key? "Being a good reader," said Freeman. "Not much more than that.")

But when Caine was explaining about the magic tricks in the film, Freeman closed his eyes for a notable amount of time and his head bobbed low on his chest as if he'd briefly fallen asleep. (Watch the video here.)

For a while, the station cut away to scenes from the film, and when they cut back, Freeman's head was resting on his chest and he did appear to be napping. He quickly shook his head and was back in the game.

The station seemed convinced Freeman had actually dozed off, writing in an article about the video, "It?s OK, Morgan. We all know Bill?s voice can lull you into sleep."

Freeman's representative did not immediately respond to a TODAY.com request for comment.

Freeman's tiredness may be understandable -- it was likely the last interview in a lengthy lineup. After the anchors had said goodbye, the actors' microphones were left on, and Caine could be heard asking, "Is this the last one?" Yes it was. Hope the two got some sleep.

Source: http://www.today.com/entertainment/morgan-freeman-appears-doze-during-live-interview-6C10037801

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BMJ: Megastudy links pediatric CT to higher cancer rates

Researchers studied the records of nearly 700,000 children and young adults who had CT examinations between 1985 and 2005, finding more than 60,000 cancers including 3,150 that occurred at least one year after a CT scan. They compared these records with those of more than 10 million people who were not scanned. After accounting for a wide range of demographic factors, they found the overall cancer incidence in this group was 24% higher than for unexposed individuals, with the greatest increases seen in brain cancer and several solid organ cancers, as well as in younger patients.

"Our study shows that CT scans during childhood and adolescence are followed by an increase in cancer incidence for all cancers combined and for many individual types of cancer," wrote Dr.?John Mathews, professorial fellow and epidemiologist at Melbourne Medical School, and colleagues from several other Australian institutions. "We cannot, however, necessarily assume that all the excess cancers seen during the current period of follow-up were caused by CT scans, because scanning decisions are based on medical indications and are not allocated at random," (BMJ, May 21, 2013).

Still, the finding that cancer incidence was linked to the site of the irradiation showed that the scans themselves were likely to be the cause of many of the post-CT malignancies recorded during the mean 9.5-year follow-up, the group wrote, cautioning that the precise cost of the scans cannot be determined as the malignancies continue to appear over time.

An accompanying editorial by Dr.?Aaron Sodickson, section chief of emergency radiology and medical director of CT at Brigham and Women's Hospital in Boston, lauded the study's careful assessment of cancer data as an excellent step toward clarifying the effects of CT radiation, but said that capturing real-time information on radiation exposure over time would provide even better data going forward.

"Such data capture would also enable more accurate patient-specific dose estimation than was possible from the data sources available to Mathews and colleagues," Sodickson wrote. "Although the authors assigned credible doses to the scans in their study, future epidemiological work may be greatly enhanced by improved capture of patient-specific dosimetry."

"With further validation of radiation risk models, not only in children but also in adults, we will ultimately be able to perform more accurate patient-specific risk assessment to better inform imaging decisions," Sodickson continued. "Mathews and colleagues' study is a vital step towards this goal."

Data still unclear

Some recent studies have offered estimates of the risks associated with low doses of ionizing radiation, including a U.K. study of 180,000 showing increasing incidence of leukemia and brain cancer that mirrored medical doses received. But some have questioned the validity of this and other studies, and much uncertainty remains.

Mathews and colleagues looked at Australian Medicare records over 20 years in an effort to provide clearer long-term answers about the effects of CT radiation, specifically assessing cancer incidence among individuals exposed to CT more than a year before a cancer diagnosis compared with the unexposed population. To arrive at estimated effective exposures, scanner settings were estimated based on common practice including reduced exposure settings for younger patients.

The 10.9 million people identified from Australian Medicare records were all between the ages of 0 and 19 years in January 1985, or born between then and December 2005. From this group, the authors identified 680,211 individuals exposed to CT scans, linking the data through national medical records to 3,150 scanned patients who were diagnosed with cancer at least a year after CT through the end of 2007, with a mean follow-up of 9.5 years.

Cancer incidence higher for scanned patients

The overall cancer incidence was 24% greater for exposed individuals compared with unexposed people, after accounting for age, sex, and year of birth, for an incidence rate ratio (IRR) of 1.24 (95% confidence interval 1.20 to 1.29; p < 0.001). Moreover, the IRR increased by 16% (0.13 to 0.19) with each additional CT scan (p < 0.001 for trend), the study team reported. The increased incidence did not disappear over time for the exposed patients, although it slowed.

"When the calculations were repeated based on lag periods of five and 10 years, cancer incidence remained higher in the exposed group than in the unexposed group, although the proportional increases were smaller compared with those based on the one-year lag period," they wrote. Thus, for the five-year lag period the IRR was 1.21 (1.16 to 1.26, p < 0.001) versus 1.18 (1.11 to 1.24, p < 0.001) for the 10-year lag period.

The IRR for exposed individuals versus the unexposed rose not only for all cancers combined but for solid cancers, lymphoid, and blood-based cancers looked at separately.

Brain cancer showed the highest increase in IRR, with other significant increases in cancers of the digestive organs, melanoma, soft tissue, female genital organs, urinary tract, thyroid, and ill-defined or unspecified sites, as well as Hodgkin's lymphoma, other lymphoid cancers, leukemias, and myelodysplasias.

Brain cancer shows sharpest increase

Almost three-fifths of the scans were of the brain, so the authors performed a new analysis excluding these. The IRR for brain cancers after the patient was scanned in another anatomic site remained elevated (IRR 1.51) as did IRRs for all solid cancers (IRR 1.19) and all cancers (IRR 1.20).

On the other hand, the authors found a highly significant reduction in IRR for all solid cancers except brain cancer after a CT scan as the age of exposure increased (p = 0.01 for trend). However, there was no significant trend in the absolute excess incidence rate (EIR) with increasing age at exposure. For brain cancer as well as for all cancers combined, IRRs were highest for CT exposures in children younger than 5 years, and the risk fell with increasing age at the first CT exposure (p = 0.001 for brain cancer, p < 0.001 for trend for all cancers). In fact for all cancers, IRR decreased with increasing age, though it remained higher than unexposed individuals for all cancers.

"Our study shows that CT scans during childhood and adolescence are followed by an increase in cancer incidence for all cancers combined and for many individual types of cancer," Mathews and colleagues wrote. "We cannot, however, necessarily assume that all the excess cancers seen during the current period of follow-up were caused by CT scans, because scanning decisions are based on medical indications and are not allocated at random."

As a result, reverse causation -- whereby symptoms of precancerous conditions are evaluated by CT -- cannot be ruled out, and this effect is most likely for brain cancers, where symptoms prompting a CT scan might appear years before cancer manifests.

Controls don't account for differences

Several study observations do make it likely that CT scans cause most of the excess cancers. These include the finding that IRR increased with an increasing number of scans -- the finding that younger patients were hit with larger proportional increases in cancer incidence as seen in the Japanese bomb survivor data. In addition, the study showed a larger absolute EIR in female patients versus male patients exposed to CT, and that the site of the CT scans was correlated to the cancer site, with a large increase in EIR for leukemias and myelodysplasias following exposure of the red bone marrow after CT scans of the abdomen and pelvis.

"This observed increase in risk associated with the low radiation doses delivered by CT scans supports the most widely adopted linear-no-threshold dose-response model in which double the radiation dose is assumed to impart double the cancer risk," Sodickson wrote in his editorial. "The reported risks also roughly match the lifetime attributable risks predicted by the BEIR-VII (biological effects of ionizing radiation) report; one of the most commonly used linear-no-threshold models."

The finding that will generate the most headlines is that childhood exposure boosts the incidence of cancer by 24%, he continued. "However, it is important to recognize that the baseline incidence of cancer in a general pediatric population is extremely small, so that a 24% increase makes this risk just slightly less small."

Clear message for physicians

Doctors will increasingly need to weigh the benefits of CT against the potential risks, Mathews and colleagues noted.

"Fortunately, many radiologists are now aware of the risks, and technological advances have already allowed CT scan doses to be reduced below those used in earlier decades," they wrote. "However, decision tools to objectively assess the need for CT are still not used routinely."

Sodickson stated there are many opportunities before, during, and after scans to cut exposure, and that physicians must make use of every opportunity to do so. Dosimetry, the collection of cumulative exposure data, and rigorous adherence to evidence-based scanning decisions represent important opportunities.

"Imaging algorithms or evidence-based clinical decision rules may be adopted for clearly defined clinical scenarios. Electronic decision support embedded in the scan ordering process can substantially reduce utilization," he wrote.

Source: http://www.auntminnie.com/redirect/redirect.aspx?itemid=103512&wf=1

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Astronauts Go On Spacewalk To Fix Ammonia Leak

Two astronauts went on a last-minute spacewalk Saturday to replace a pump suspected of being the source of a serious ammonia leak.

It was unclear what caused the ammonia leak, NASA spokesman Rob Navias said, "but the installation of this spare pump package ? at least at the moment ? seems to have done the trick."

According to The Associated Press, NASA said the leak never jeopardized the crew at the International Space Station, but the agency wanted to fix the problem while it was fresh.

NASA plans to hold a press conference about the spacewalk at 4:30 p.m. ET. You can watch it live on NASA's videostream:

Our Original Post Continues:

As two astronauts make what The Associated Press writes is "a hastily planned spacewalk Saturday to try to fix an ammonia leak in the power system of the International Space Station," NASA is webcasting.

It's estimated they'll be working on the problem for about six hours. The leak is not presenting a danger, NASA says, and the space station still has plenty of power.

Update at 3:08. ET. : New Pump Installed

NASA says astronauts Chris Cassidy and Tom Marshburn replaced a pump controller box suspected of being the source of the ammonia leak. The Associated Press reports they uncovered "no smoking guns" responsible for the problem.

Source: http://www.npr.org/blogs/thetwo-way/2013/05/11/183100829/live-webcast-of-astronauts-spacewalk?ft=1&f=1007

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