Science Blogversation
LiveWire presents our first Science Blogversation. This inaugural event focuses
on Nanoscience and Nanotechnology. We’ve invited a panel of guests to blog with us on this topic; to
help us understand where we are and where we’re going.
Bacteria make fine machines when the job is small enough The Washington Post Jan. 15, page A6, by Rick Weiss
Say you want to gently mix tiny amounts of fluids in nearly microscopic tubes. Even the smallest pump would overwhelm the system, and no one makes propellers or sloshing machines that small. Who you gonna call? Bacteria, say a pair of researchers who use their talents in engineering and microbiology to recruit microbes into the scientific labor force. … Min Jun Kim of Drexel University and Kenneth S. Breuer of Brown University were aware of a growing market for “microfluidic” laboratory instruments—blood analyzers and other machines that work by mixing chemical reagents together and are so miniaturized that the fluid tubes are as thin as hairs. ... In experiments, the scientists showed that a tiny dose of bacteria could double the rate of the fluids’ mixing in microchannels. When the fluid was spiked with a chemical that excites bacteria, the rate doubled again. Bacteria “provide a natural mechanism for achieving mixing,” the team concludes in the current web edition of the journal Analytical Chemistry.
From lowly potato to super spud: A lower glycemic index? More disease-fighting nutrients? Anything’s possible. The Los Angeles Times Jan. 15
Potatoes have had some very bad press of late, but now, in labs across the country, those spunky spuds may be staging a comeback. A low-carb breed is already on the market; researchers have produced a low-acrylamide variety; and work is underway to try to solve the blood sugar problem too. … They’re also working to give it some new assets. The potatoes most of us eat are naturally high in vitamin C and potassium, but researchers hope to add other vitamins and minerals to the mix by taking advantage of the potato’s huge gene pool. Lots of traits in potatoes aren’t developed,” adds Caius Rommens, director of plant sciences at J.R. Simplot, an agribusiness company based in Idaho. … In a paper published this month in the Journal of Agricultural and Food Chemistry, he and his colleagues report significant progress on that front—a fry that’s prettier, smells better and is significantly lower in acrylamide.
Grape pulp is cardioprotective United Press International Jan. 11
MILAN, Italy—The flesh of grapes is equally cardioprotective as the skin of grapes, according to U.S. and Italian researchers. Researchers at the University of Connecticut School of Medicine, the University of Milan and several other research institutes in Italy have found evidence that the pulp of grapes appears just as heart-healthy in laboratory experiments as the skin. The study, published in the American Chemical Society’s Journal of Agricultural & Food Chemistry, challenges the idea that red wine is more heart-healthy than white wine.
Oral insulin works in tests on rats CBSNews.com Jan. 10
(WebMD) Oral insulin may be one step closer to becoming available to people who now have to take shots for their diabetes. Scientists in Taiwan report success in early tests of an oral insulin solution in diabetic rats. … “Multiple daily injections of insulin are currently the standard treatment for insulin-dependent diabetic patients,” write the Taiwanese researchers, who include Hsing-Wen Sung, PhD, of Taiwan’s National Tsing Hua University. ... Lab tests showed the insulin reached the rats’ bloodstream and lowered their blood glucose (sugar) levels. The Taiwanese study appears in the journal Biomacromolecules.
Another kind of fairway hazard The New York Times Jan. 9, by Henry Fountain
Your typical golf course is hardly an all-natural playground. To create verdant fairways, lush rough and tight greens, all manner of chemicals, including pesticides, are usually needed. Might that have an effect on golfers, who may breathe in pesticide vapors while playing? A study by Rebecca R. Murphy and Douglas A. Haith of Cornell shows that there is little inhalation risk, at least at courses in the Northeast. The study, published by the journal Environmental Science and Technology, assessed the health risks of 15 pesticides, including fungicides like azoxystrobin and iprodione and herbicides like bensulide, which is used to control crabgrass, at three locations, Boston, Philadelphia and Rochester.
The mouse trap: Scratch and sniff is de rigueur for wine-sellers The Guardian (United Kingdom) Jan. 9, by Marc Abrahams
Mousy off-flavour is one of the wine industry’s little embarrassments, and has been since at least the 1890s, when the concept first seeped into published documents. Few have written or spoken of it plainly. Now a team of Australian food scientists is dishing the dirt on mousy off-flavour, with a study in the Journal of Agricultural and Food Chemistry. … Eleanor Snowdon, Michael Bowyer, Paul Grbin and Paul Bowyer, who are variously at the University of Adelaide and the University of Newcastle (the one in New South Wales, not the one in Northumberland), peeped and poked into the wine-dark recesses of many libraries. They found several dozen scientific reports that mention, or at least relate to, mousy off-flavour. One early paper serves up a sniffy description. Mousy off-flavour, it says, is a “peculiarly disagreeable flavour in wine, which is closely resembling to the smell [sic] of a residence of mice.”
Super-heating milk extends shelf life BellvilleNewsDemocrat.com Jan. 9
Putting the squeeze on milk may be the long-sought solution to killing bacteria and increasing the beverage’s shelf life without introducing unwanted flavors. Michael Qian at Oregon State University says ultrahigh-temperature pasteurization (UHT) does produce milk that stays fresh at room temperature for six months. However, the process leaves a “cooked” flavor that has limited its popularity in the United States. Now, in experiments published in a recent Journal of Agricultural and Food Chemistry, Qian and his colleague describe how high hydrostatic pressure processing (HPP) can crush bacteria without affecting flavor. “Milk processed at a pressure of about 85,000 pounds per square inch for five minutes, and lower temperatures than used in commercial pasteurization, causes minimal production of chemical compounds responsible for the cooked flavor,” they reported. “HPP gives milk a shelf life at refrigerated temperatures of at least 45 days.”
The first molecular keypad lock Huliq.com Jan. 8
How can defense or intelligence agencies safeguard the security of top-secret data protected by a computation device the size of a single molecule? With cryptography approaching that sobering new era, scientists in Israel are reporting development of what they term the first molecular system capable of processing password entries. Abraham Shanzer and colleagues describe their “molecular keypad lock” in the Jan. 17 issue of the weekly Journal of the American Chemical Society. Electronic keypad locks long have been fixtures on home security systems and other devices that require a password. The new study, however, describes a keypad lock based on molecules that fluoresce only in response to the correct sequences of three input signals.
Bamboo leaf extract to stop acrylamide formation? Food Navigator Jan. 4, by Stephen Daniells
Using an antioxidant-rich bamboo leaf extract could reduce the formation of acrylamide in potato chips and French fries by about 75 per cent, according to a new study. “This study could be regarded as a pioneer contribution on the reduction of acrylamide in various foods by natural antioxidants,” wrote lead author Yu Zhang in the Journal of Agricultural and Food Chemistry. Acrylamide is a carcinogen that is created when starchy foods are baked, roasted, fried or toasted. It first hit the headlines in 2002, when scientists at the Swedish Food Administration first reported unexpectedly high levels of acrylamide, found to cause cancer in laboratory rats, in carbohydrate-rich foods. ... The researchers, from Zhejiang University’s Department of Food Science and Nutrition, report that by immersing the potato crisps and French fries in bamboo leaf extract so that the extract penetrated into the potato matrix prior to the frying process, could reduce the formation of this cancer-causing compound.
Tiny discovery could be big deal: UD researchers develop a new method of producing ultrathin films DelawareOnline/The News Journal Jan. 4
NEWARK — For decades, textbooks said it was impossible. In classes, students were told it couldn’t be done. Year after year, in lab after lab, chemists assumed it was a pointless quest: You simply can’t string together a certain type of molecule well enough to build the long, orderly “polymer” chains that are used to make plastics and other man-made materials. Apparently, all the textbooks, and all those scientists, were just plain wrong. That’s the conclusion reached by a team of University of Delaware researchers who claim to have created the first successful polymer film using a class of molecules known as “1,2-disubstituted ethylenes.”… Making these minuscule materials has been a momentous challenge for professors Jochen Lauterbach and Chris Snively. ... Lauterbach remains a bit amazed by it all. “Frankly, we didn’t think we’d be able to make them.” So some in the scientific community were a bit incredulous as well, as the team learned when they submitted in the summer their findings to the Journal of the American Chemical Society.
High aflatoxin levels in wild bird feed HULIQ (North Carolina) Jan. 1
Wild birdseed contained higher levels of aflatoxins and other mycotoxins than any other kind of pet food analyzed in studies done around the world, a new review of those studies reports in an article scheduled for the Dec. 27 issue of ACS’s Journal of Agricultural and Food Chemistry. Trevor K. Smith and colleagues at the University of Guelph in Ontario point out that mycotoxins are harmful compounds produced by fungi that can grow in cereal grains and nuts used in many pet foods. The compounds are carcinogenic and have other ill effects when consumed at sufficient doses.
Removing lead paint, safely The New York Times Dec. 19, by Henry Fountain
If you’ve ever tried to remove old paint from a door or molding, you know how difficult the job can be. If the paint contains lead (as many household paints did before 1978, when a ban went into effect), then a difficult task can become a potentially hazardous one. Ingested lead can lead to severe health problems, particularly in children. ... A promising new method that uses light has been tested by its developer, Phoenix Science and Technology of Chelmsford, Mass. Michael J. Grapperhaus and Raymond B. Schaefer of the company report in the journal Environmental Science and Technology that the system effectively removed paint without putting a lot of lead into the air. The system uses a surface discharge lamp, a type that creates extremely short, high-intensity pulses. Equipped with an elliptical reflector to focus the light, the lamp can vaporize layers of paint without heating up or burning the wood underneath.
Silicone breast implants: New concerns CBS News online Dec. 18
(WebMD) One month after the FDA approved the return of silicone gel–filled breast implants to the U.S. market, a European study is raising new concerns about their safety. Researchers in Austria have identified proteins that accumulate on the surface of silicone breast implants, which they say could be the cause of immune reactions in women who have them. ... In the newly reported Austrian study, researchers showed that key proteins accumulate on the surface of silicone breast implants long after the implants are placed in the body. They were able to do this using a relatively new, targeted research method known as proteomics. The study appears in the December issue of the American Chemical Society publication, Journal of Proteome Research.
Real stinkers reformed: Malodorous but useful chemicals now smell sweet Scientific American Dec. 16, by Steven Ashley
Name the world’s most offensive odor: Rotting fish? Refinery fumes? Skunk spray? For many organic chemists, top honors go to a family of carbon-nitrogen–based compounds called isonitriles. This chemical group is “the Godzilla of smells ... they make you vomit your guts out instantly,” declared Luca Turin, a leading olfaction theorist and protagonist of Chandler Burr’s 2003 biography, The Emperor of Scent. Add the fact that a prime ingredient for isonitriles is phosgene gas—a notorious chemical warfare agent from World War I—and it is little surprise that many investigators shun these noxious and unstable substances despite their acknowledged utility in drug discovery, polymer manufacture and elsewhere. … Two researchers at the University of California, Riverside, have recently synthesized fragrant isonitriles that not only work just as well as their foul-smelling cousins but are safer to formulate. The aromas of the new substances include soy, malt, old wood, cherry and even taffy, report chemist Michael C. Pirrung and his postdoctoral student Subir Ghorai in the Journal of the American Chemical Society.
Cloning nanotubes Technology Review Dec. 14, By Kevin Bullis
Practical devices made of nanostructures are a step closer to being realized. Researchers at Rice University have demonstrated that carbon nanotubes can be chopped into small pieces to form “seeds” that grow more nanotubes of precisely the same type. The method could eventually make it possible to grow large amounts of carbon nanotubes with identical structure and properties, which could pave the way for a diverse set of carbon nanotube-based applications, such as vastly improved electrical transmission lines and ultracompact, high-performance computers. ... In experiments published in last week’s Journal of the American Chemical Society, the researchers confirmed in two cases that the method allows long nanotubes to grow from iron particle–carbon nanotube seeds.
Salt that doesn’t stick The New York Times Magazine Dec. 10, by Clive Thompson
Everyone knows the havoc that humidity wreaks on salt. You pick up a saltshaker, tip it upside down and—nothing. The problem is molecular. Salt grains are cube shaped, so it doesn’t take much to get them to stack together like Legos. Salt producers have created nonsticking salt before by adding chemicals to prevent binding. But this year, in the July issue of Crystal Growth and Design, a team of Indian scientists announced that they had discovered a better way to attack the problem: They produced salt that is round. To accomplish this, they added the amino acid glycine to a pan of brine and then let the salty liquid evaporate. The resulting crystals were shaped like dodecahedrons: 12-sided grains. In this nearly spherical form, the grains no longer stacked like bricks but like oranges in a sack. The researchers put some of the round salt into a container, left it for a year and found that it still poured freely.
Better living, thanks to the laboratory The St. Petersburg Times (FL) Dec. 12, by Robert N. Jenkins
Scientists in the United Kingdom have spun fine threads of a type of silicone that contains living human brain cells. The cells remained alive and capable of growth afterward, according to the lead researchers. “This will enable significant advances … ranging from tissue engineering to regenerative medicine,” researchers Suwan N. Jayasinghe and Andrea Townsend-Nicholson said last month. “The ability to ‘electrospin’ biologically active threads and scaffolds of living organisms will be tremendously useful for … novel bioengineering and medical applications.” They reported their findings in the Nov. 13 issue of the American Chemical Society’s journal, Biomacromolecules.
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