Biological Engineering

Heat Your Vegetables

2008-05-15T14:17:00.001-04:00

Crops in the tropics will do worse, since extra heat where it's already hot hurts more than it helps.

Sharon Begley
May 5, 2008 Issue

Whenever global warming began looking too bleak—with such threats as dengue fever spreading like kudzu out of the tropics, storm surges turning coasts into continental shelf and Katrinas coming almost as often as Mardi Gras—I consoled myself by turning to the Greening Earth Society. A creation of the coal industry, whose product emits more greenhouse gases than any other fossil fuel, it painted climate change in Edenic terms, promising that the atmosphere's rising levels of carbon dioxide would act like airborne fertilizer, boosting crop yields and turning marginal regions into breadbaskets.

Turns out they weren't noticing the Gangotri glacier.

One of the Himalayas' largest, it has been shrinking since the late 18th century. But over the last 25 years it has shrunk about half a mile, a rate three times the historical norm. The retreat threatens more than the loss of a panoramic background for tourist snapshots. The Gangotri supplies 70 percent of the flow of 's Ganges River during the dry season, when farmers depend on it for irrigation. Glaciers on the Tibet-Qinghai Plateau, which are also shrinking, feed major rivers in , which are also crucial for irrigation. "Without the ice melt, the Ganges and the Yellow rivers could dry up in the dry season, shrinking harvests," says , president of the Earth Policy Institute. "If the Ganges flows only part of the year, double cropping [in which farmers plant rice and wheat in back-to-back growing seasons, and which underlies India's green revolution] breaks down."

There is nothing like food riots to concentrate the mind on how climate change will affect harvests. You'd think that, for agriculture, warmer is better. Peach harvests are more bountiful in Georgia than Vermont, and the nation's breadbasket isn't North Dakota. No surprise, then, that the international panel of scientists that analyzes climate change concluded last year that the mid- and high latitudes will enjoy higher crop yields when average temperatures rise 1 to 3 degrees above today's, something we're on track for by 2020. Crops in the tropics and subtropics will generally fare worse, though, because "most tropical plants are already very close to the maximum temperature they can thrive in," says William Easterling of Penn State, who oversaw the analysis of climate change and food production for the . "Any warming pushes them beyond the optimum for photosynthesis and yield." But then, global warming was always going to produce some winners and some losers. (Look for Siberian wheat in your favorite ciabatta any day now.) However, details such as how vanishing glaciers will affect rivers that provide irrigation water to India and China are only now being factored in, and the results are enough to make you hoard 20-pound bags of rice.

Rain is one of those details. Overall, global warming will bring more rainfall, partly because warmer air holds more moisture. But rainfall has been coming in fits and starts—dry spells interrupted by deluges. That is a prescription for withering crops and then washing them away. More such "precipitation extremes," as the IPCC delicately calls them, are likely in South and East Asia, parts of Australia (which recently suffered its worst drought since 1900) and Northern Europe. Globally, the amount of land experiencing very dry conditions rose from less than 15 percent in 1970 to 35 percent today. You have to plow through 279 pages of the IPCC report to discover that its projections of higher crop yields in a slightly warmer world "do not yet include these recent findings on projected patterns of change in precipitation."

Even if average temps rise only a little, a greenhouse world has more heat waves. During Europe's 2003 scorcher, which brought temperatures 10 degrees above normal, Italy's corn yields fell 36 percent (a record), France's fruit harvest fell 25 percent and wine production was the lowest in 10 years. Crop losses totaled $14.6 billion. Get used to it. "In the past, the negative effect of unusual weather events was always temporary; within a year or two, things returned to normal," says Brown. "With climate in flux, there is no normal to return to."

In the United States, diminishing snowpack, particularly in the North-west, means less water is stored for the growing season. But the greater risk posed by climate change is that the match between weather and soil conditions will break down. Just because climate zones shift north doesn't mean crops can easily shift with them, says of the National Center for Atmospheric Research. Corn grows in Iowa and wheat in because those pairings provide the ideal climate, soil and—crucially—"photoperiod." Plants need a precise amount of sunlight and day length to thrive, but "the sun will not move with the climate," says Mearns; the Dakotas will always have less daylight than Kansas, and thus be less hospitable to crops. Higher temps also mean that fewer crops are pollinated: corn tassels dry up above about 70 degrees; rice pollination falls from 100 percent at current temperatures to 50 percent if the world gets 3 degrees warmer. Since governments are doing basically nothing to avert global warming, our agriculture policy amounts to this: pray for good weather.

© 2008

AP probe finds drugs in drinking water

2008-03-09T16:49:00.003-04:00

By JEFF DONN, MARTHA MENDOZA and JUSTIN PRITCHARD, Associated Press Writers Sun Mar 9, 1:00 PM ET

A vast array of pharmaceuticals — including antibiotics, anti-convulsants, mood stabilizers and sex hormones — have been found in the drinking water supplies of at least 41 million Americans, an Associated Press investigation shows.

To be sure, the concentrations of these pharmaceuticals are tiny, measured in quantities of parts per billion or trillion, far below the levels of a medical dose. Also, utilities insist their water is safe.
But the presence of so many prescription drugs — and over-the-counter medicines like acetaminophen and ibuprofen — in so much of our drinking water is heightening worries among scientists of long-term consequences to human health.

In the course of a five-month inquiry, the AP discovered that drugs have been detected in the drinking water supplies of 24 major metropolitan areas — from Southern California to Northern New Jersey, from Detroit to Louisville, Ky.

Water providers rarely disclose results of pharmaceutical screenings, unless pressed, the AP found. For example, the head of a group representing major California suppliers said the public "doesn't know how to interpret the information" and might be unduly alarmed.
How do the drugs get into the water?

People take pills. Their bodies absorb some of the medication, but the rest of it passes through and is flushed down the toilet. The wastewater is treated before it is discharged into reservoirs, rivers or lakes. Then, some of the water is cleansed again at drinking water treatment plants and piped to consumers. But most treatments do not remove all drug residue.

And while researchers do not yet understand the exact risks from decades of persistent exposure to random combinations of low levels of pharmaceuticals, recent studies — which have gone virtually unnoticed by the general public — have found alarming effects on human cells and wildlife.

"We recognize it is a growing concern and we're taking it very seriously," said Benjamin H. Grumbles, assistant administrator for water at the U.S. Environmental Protection Agency.
Members of the AP National Investigative Team reviewed hundreds of scientific reports, analyzed federal drinking water databases, visited environmental study sites and treatment plants and interviewed more than 230 officials, academics and scientists. They also surveyed the nation's 50 largest cities and a dozen other major water providers, as well as smaller community water providers in all 50 states.

Here are some of the key test results obtained by the AP:

_Officials in Philadelphia said testing there discovered 56 pharmaceuticals or byproducts in treated drinking water, including medicines for pain, infection, high cholesterol, asthma, epilepsy, mental illness and heart problems. Sixty-three pharmaceuticals or byproducts were found in the city's watersheds.

_Anti-epileptic and anti-anxiety medications were detected in a portion of the treated drinking water for 18.5 million people in Southern California.

_Researchers at the U.S. Geological Survey analyzed a Passaic Valley Water Commission drinking water treatment plant, which serves 850,000 people in Northern New Jersey, and found a metabolized angina medicine and the mood-stabilizing carbamazepine in drinking water.

_A sex hormone was detected in San Francisco's drinking water.

_The drinking water for Washington, D.C., and surrounding areas tested positive for six pharmaceuticals.

_Three medications, including an antibiotic, were found in drinking water supplied to Tucson, Ariz.

The situation is undoubtedly worse than suggested by the positive test results in the major population centers documented by the AP.

The federal government doesn't require any testing and hasn't set safety limits for drugs in water. Of the 62 major water providers contacted, the drinking water for only 28 was tested. Among the 34 that haven't: Houston, Chicago, Miami, Baltimore, Phoenix, Boston and New York City's Department of Environmental Protection, which delivers water to 9 million people.
Some providers screen only for one or two pharmaceuticals, leaving open the possibility that others are present.

The AP's investigation also indicates that watersheds, the natural sources of most of the nation's water supply, also are contaminated. Tests were conducted in the watersheds of 35 of the 62 major providers surveyed by the AP, and pharmaceuticals were detected in 28.

Yet officials in six of those 28 metropolitan areas said they did not go on to test their drinking water — Fairfax, Va.; Montgomery County in Maryland; Omaha, Neb.; Oklahoma City; Santa Clara, Calif., and New York City.

The New York state health department and the USGS tested the source of the city's water, upstate. They found trace concentrations of heart medicine, infection fighters, estrogen, anti-convulsants, a mood stabilizer and a tranquilizer.

City water officials declined repeated requests for an interview. In a statement, they insisted that "New York City's drinking water continues to meet all federal and state regulations regarding drinking water quality in the watershed and the distribution system" — regulations that do not address trace pharmaceuticals.

In several cases, officials at municipal or regional water providers told the AP that pharmaceuticals had not been detected, but the AP obtained the results of tests conducted by independent researchers that showed otherwise. For example, water department officials in New Orleans said their water had not been tested for pharmaceuticals, but a Tulane University researcher and his students have published a study that found the pain reliever naproxen, the sex hormone estrone and the anti-cholesterol drug byproduct clofibric acid in treated drinking water.

Of the 28 major metropolitan areas where tests were performed on drinking water supplies, only Albuquerque; Austin, Texas; and Virginia Beach, Va.; said tests were negative. The drinking water in Dallas has been tested, but officials are awaiting results. Arlington, Texas, acknowledged that traces of a pharmaceutical were detected in its drinking water but cited post-9/11 security concerns in refusing to identify the drug.

The AP also contacted 52 small water providers — one in each state, and two each in Missouri and Texas — that serve communities with populations around 25,000. All but one said their drinking water had not been screened for pharmaceuticals; officials in Emporia, Kan., refused to answer AP's questions, also citing post-9/11 issues.

Rural consumers who draw water from their own wells aren't in the clear either, experts say.
The Stroud Water Research Center, in Avondale, Pa., has measured water samples from New York City's upstate watershed for caffeine, a common contaminant that scientists often look for as a possible signal for the presence of other pharmaceuticals. Though more caffeine was detected at suburban sites, researcher Anthony Aufdenkampe was struck by the relatively high levels even in less populated areas.

He suspects it escapes from failed septic tanks, maybe with other drugs. "Septic systems are essentially small treatment plants that are essentially unmanaged and therefore tend to fail," Aufdenkampe said.

Even users of bottled water and home filtration systems don't necessarily avoid exposure. Bottlers, some of which simply repackage tap water, do not typically treat or test for pharmaceuticals, according to the industry's main trade group. The same goes for the makers of home filtration systems.

Contamination is not confined to the United States. More than 100 different pharmaceuticals have been detected in lakes, rivers, reservoirs and streams throughout the world. Studies have detected pharmaceuticals in waters throughout Asia, Australia, Canada and Europe — even in Swiss lakes and the North Sea.

For example, in Canada, a study of 20 Ontario drinking water treatment plants by a national research institute found nine different drugs in water samples. Japanese health officials in December called for human health impact studies after detecting prescription drugs in drinking water at seven different sites.

In the United States, the problem isn't confined to surface waters. Pharmaceuticals also permeate aquifers deep underground, source of 40 percent of the nation's water supply. Federal scientists who drew water in 24 states from aquifers near contaminant sources such as landfills and animal feed lots found minuscule levels of hormones, antibiotics and other drugs.
Perhaps it's because Americans have been taking drugs — and flushing them unmetabolized or unused — in growing amounts. Over the past five years, the number of U.S. prescriptions rose 12 percent to a record 3.7 billion, while nonprescription drug purchases held steady around 3.3 billion, according to IMS Health and The Nielsen Co.

"People think that if they take a medication, their body absorbs it and it disappears, but of course that's not the case," said EPA scientist Christian Daughton, one of the first to draw attention to the issue of pharmaceuticals in water in the United States.

Some drugs, including widely used cholesterol fighters, tranquilizers and anti-epileptic medications, resist modern drinking water and wastewater treatment processes. Plus, the EPA says there are no sewage treatment systems specifically engineered to remove pharmaceuticals.
One technology, reverse osmosis, removes virtually all pharmaceutical contaminants but is very expensive for large-scale use and leaves several gallons of polluted water for every one that is made drinkable.

Another issue: There's evidence that adding chlorine, a common process in conventional drinking water treatment plants, makes some pharmaceuticals more toxic.

Human waste isn't the only source of contamination. Cattle, for example, are given ear implants that provide a slow release of trenbolone, an anabolic steroid used by some bodybuilders, which causes cattle to bulk up. But not all the trenbolone circulating in a steer is metabolized. A German study showed 10 percent of the steroid passed right through the animals.

Water sampled downstream of a Nebraska feedlot had steroid levels four times as high as the water taken upstream. Male fathead minnows living in that downstream area had low testosterone levels and small heads.

Other veterinary drugs also play a role. Pets are now treated for arthritis, cancer, heart disease, diabetes, allergies, dementia, and even obesity — sometimes with the same drugs as humans. The inflation-adjusted value of veterinary drugs rose by 8 percent, to $5.2 billion, over the past five years, according to an analysis of data from the Animal Health Institute.

Ask the pharmaceutical industry whether the contamination of water supplies is a problem, and officials will tell you no. "Based on what we now know, I would say we find there's little or no risk from pharmaceuticals in the environment to human health," said microbiologist Thomas White, a consultant for the Pharmaceutical Research and Manufacturers of America.

But at a conference last summer, Mary Buzby — director of environmental technology for drug maker Merck & Co. Inc. — said: "There's no doubt about it, pharmaceuticals are being detected in the environment and there is genuine concern that these compounds, in the small concentrations that they're at, could be causing impacts to human health or to aquatic organisms."

Recent laboratory research has found that small amounts of medication have affected human embryonic kidney cells, human blood cells and human breast cancer cells. The cancer cells proliferated too quickly; the kidney cells grew too slowly; and the blood cells showed biological activity associated with inflammation.

Also, pharmaceuticals in waterways are damaging wildlife across the nation and around the globe, research shows. Notably, male fish are being feminized, creating egg yolk proteins, a process usually restricted to females. Pharmaceuticals also are affecting sentinel species at the foundation of the pyramid of life — such as earth worms in the wild and zooplankton in the laboratory, studies show.

Some scientists stress that the research is extremely limited, and there are too many unknowns. They say, though, that the documented health problems in wildlife are disconcerting.

"It brings a question to people's minds that if the fish were affected ... might there be a potential problem for humans?" EPA research biologist Vickie Wilson told the AP. "It could be that the fish are just exquisitely sensitive because of their physiology or something. We haven't gotten far enough along."

With limited research funds, said Shane Snyder, research and development project manager at the Southern Nevada Water Authority, a greater emphasis should be put on studying the effects of drugs in water.

"I think it's a shame that so much money is going into monitoring to figure out if these things are out there, and so little is being spent on human health," said Snyder. "They need to just accept that these things are everywhere — every chemical and pharmaceutical could be there. It's time for the EPA to step up to the plate and make a statement about the need to study effects, both human and environmental."

To the degree that the EPA is focused on the issue, it appears to be looking at detection. Grumbles acknowledged that just late last year the agency developed three new methods to "detect and quantify pharmaceuticals" in wastewater. "We realize that we have a limited amount of data on the concentrations," he said. "We're going to be able to learn a lot more."

While Grumbles said the EPA had analyzed 287 pharmaceuticals for possible inclusion on a draft list of candidates for regulation under the Safe Drinking Water Act, he said only one, nitroglycerin, was on the list. Nitroglycerin can be used as a drug for heart problems, but the key reason it's being considered is its widespread use in making explosives.

So much is unknown. Many independent scientists are skeptical that trace concentrations will ultimately prove to be harmful to humans. Confidence about human safety is based largely on studies that poison lab animals with much higher amounts.

There's growing concern in the scientific community, meanwhile, that certain drugs — or combinations of drugs — may harm humans over decades because water, unlike most specific foods, is consumed in sizable amounts every day.

Our bodies may shrug off a relatively big one-time dose, yet suffer from a smaller amount delivered continuously over a half century, perhaps subtly stirring allergies or nerve damage. Pregnant women, the elderly and the very ill might be more sensitive.

Many concerns about chronic low-level exposure focus on certain drug classes: chemotherapy that can act as a powerful poison; hormones that can hamper reproduction or development; medicines for depression and epilepsy that can damage the brain or change behavior; antibiotics that can allow human germs to mutate into more dangerous forms; pain relievers and blood-pressure diuretics.

For several decades, federal environmental officials and nonprofit watchdog environmental groups have focused on regulated contaminants — pesticides, lead, PCBs — which are present in higher concentrations and clearly pose a health risk.

However, some experts say medications may pose a unique danger because, unlike most pollutants, they were crafted to act on the human body.

"These are chemicals that are designed to have very specific effects at very low concentrations. That's what pharmaceuticals do. So when they get out to the environment, it should not be a shock to people that they have effects," says zoologist John Sumpter at Brunel University in London, who has studied trace hormones, heart medicine and other drugs.

And while drugs are tested to be safe for humans, the timeframe is usually over a matter of months, not a lifetime. Pharmaceuticals also can produce side effects and interact with other drugs at normal medical doses. That's why — aside from therapeutic doses of fluoride injected into potable water supplies — pharmaceuticals are prescribed to people who need them, not delivered to everyone in their drinking water.

"We know we are being exposed to other people's drugs through our drinking water, and that can't be good," says Dr. David Carpenter, who directs the Institute for Health and the Environment of the State University of New York at Albany.
____
The AP National Investigative Team can be reached at investigate (at) ap.org

Ethics rules send NIH scientists packing

2006-10-29T08:26:00.000-05:00

By RITA BEAMISH, Associated Press Writer
Sat Oct 28, 6:06 PM ET

Nearly 40 percent of the scientists conducting hands-on research at the National Institutes of Health say they are looking for other jobs or are considering doing so to escape new ethics rules that have curtailed their opportunity to earn outside income.

Most scientists say the ethics crackdown is too severe, and nearly three-quarters of them believe it will hinder the government's ability to attract and keep medical researchers, according to a survey commissioned by the government's premier medical research agency.

The tightened rules were put in place last year after NIH found dozens of scientists had run afoul of existing restrictions on private consulting deals that had enriched them with money from drug and biotechnology companies.

Outside income from such companies is now banned. NIH also is placing greater restrictions and disclosure requirements on employees' financial holdings.

"Of course we are concerned when any employees are saying they might consider leaving as a result of a change of policy," said Dr. Raynard Kington, the agency's principal deputy director. But he said in a telephone interview Friday that the survey results are muddy because they combine both those actively seeking to leave and those thinking about it.

NIH Director Elias Zerhouni, in a letter Thursday to the staff, said the survey "does suggest concerns about the impact of the regulations on recruitment and retention." But he added, "At this time we do not anticipate revisions in the regulations."

About 8,000 NIH employees, or about half the work force, responded to the Internet-based survey.

Employee job satisfaction was high overall, the survey found. But 39 percent of the scientists researching disease and cures — known as tenure and tenure-track scientists — said they actively were seeking new work or considering leaving NIH because of the rules.

Overall, 3,336 NIH scientists responded to the survey, including 512 tenure and tenure-track researchers.

Among all NIH scientists, only 18 percent said they were trying to leave or considering it. Those who are not in the tenure group typically do not conduct research themselves and instead manage outside research conducted with NIH money by universities and other nonfederal entities. They are less likely to have private consulting opportunities.

One-third of all NIH scientists said they believed the new rules will hurt NIH's ability to fulfill its mission, and most said the old rules could have been enforced better rather than tightened.

NIH officials said they now want to question former and potential employees to see how the changes influenced their decisions.

Kington highlighted a finding that nearly nine in 10 scientists reported they still intend to work at NIH a year from now. Despite rumblings of low morale, he said the scientists' job satisfaction rate of 81 percent reflects one of the government's most positive work forces.

Officials also emphasized employees' belief that the new rules will boost the agency's credibility with the public. Seventy-three percent of the employees who responded agreed with that, the survey found.

"We have to monitor closely and we'll continue do that, and if we show through our evaluations objective evidence of an impact on our ability to recruit and retain the smartest staff, scientific and nonscientific, that we can, then we will be the first ones to make the case for modifying the rules, but we're not there yet," Kington said.

One NIH administrator who left over the ethics rules said the agency's changes were handled poorly.

"Dedicated public servants were harassed right out of NIH. That's a disservice to us all," said Edward Maibach, the former associate director of the biggest NIH component, the National Cancer Institute. He is now director of Public Health Communication at the George Washington University. Maibach said he left the NCI nearly two years ago because new financial disclosure requirements invaded his privacy.

The changes are "a dramatic backlash," to earlier policies encouraging outside work by NIH scientists to speed practical application of scientific advances, he said.

Arthur Caplan, medical ethics chairman at the University of Pennsylvania, said tighter rules were needed but "we still haven't figured out exactly how to manage conflict of interest."

"To have a large number of the senior scientists unhappy spells trouble. You don't want them to retire or leave," he said.

"The leaders of the NIH and in Congress have to think a bit harder about giving a tiny bit of breathing room so that NIH scientists are not sent into a monastery from which they can't ever come out in the name of scientific integrity."

___

On the Web:

NIH survey: http://www.nih.gov/about/ethics/evaluationslides.pdf

Memo on survey results: http://www.nih.gov/about/ethics/10262006COImemo.htm

Have an Unused Barn? Raise Some Fish in It

2006-08-16T08:56:00.000-04:00

08/15/2006

Have an Unused Barn? Raise Some Fish in It

LONDON, Ohio -- Ohio producers unsure of what to make of their unused hog, veal or poultry barns have the option of turning the structures into a viable aquaculture facility.

Farmers across the state are converting their barns into re-circulating aquaculture systems and Ohio State University aquaculturists with South Centers at Piketon in Piketon, Ohio, are educating farmers on how to make the switch through a $25,000 U.S. Department of Agriculture grant.

"I get a lot of phone calls that start out, ‘I've got this barn….'," said Laura Tiu, an OSU Extension aquaculturist with South Centers. "Raising fish in a barn is just one way farmers can economically maintain a facility that they would no longer use if they don't raise hogs or poultry anymore."

Tiu will be on-hand at Farm Science Review Sept. 20 at 1 p.m. at the Center for Small Farms to discuss raising fish in old farm buildings. Ohio State University's Farm Science Review will be held Sept. 19-21 at the Molly Caren Agricultural Center in London, Ohio.

Tiu and her colleagues are developing a CD that highlights the experiences of farmers who have installed a re-circulating aquaculture system in their barns, the challenges they faced, the species they chose and why, and the economics behind the installation. The disk also covers such areas as decision-making, business planning, marketing and facilities/systems. The tool is designed to inform farmers the basics of installing such a system and preparing Extension Educators for when they work with farmers interested in the idea.

Tiu, who also holds a partial Ohio Agriculture Research and Developnment Center research appointment, said that converting old barns into re-circulating aquaculture systems are growing in popularity for a number of reasons: an indoor system is more conducive to a longer season, it allows farmers to raise fish year-round as opposed to their options with ponds, it targets an underdeveloped segment of the industry, and when installed properly can generate profitable alternative revenue.

"A re-circulating system, unlike ponds, uses the same water over again. You don't drain the water after each harvest. You just put the water through a filter system, much like how an aquarium works," said Tiu. "Such a system is good for places where water may be scarce, like in southern Ohio, where it's very popular."

Of course there are downsides to a re-circulating aquaculture system, much like other production practices -- cost for one.

"There are inexpensive methods of installing aquaculture systems, in the range of $25,000. But, in the long run, they are not economical. Right now, to install a re-circulating system properly will set farmers back about a quarter million dollars," said Tiu. "But really when you think about it, that's not any more expensive that starting a hog or poultry operation."

Installation costs will also depend on the type of species a farmer wants to raise, what market will be targeted and what region of the state the system will be located.

For more on raising fish in old farm buildings, visit Farm Science Review. Farm Science Review is sponsored by Ohio State University Extension, the Ohio Agricultural Research and Development Center, and the academic units of the university's College of Food, Agricultural, and Environmental Sciences. It takes place Sept. 19-21 at the Molly Caren Agricultural Center near London, Ohio. Tickets are $8 at the gate or $5 in advance when purchased from county offices of OSU Extension or participating agribusinesses. Children 5 and younger are admitted free. Hours are 8 a.m. to 5 p.m. Sept 19-20 and 8 a.m. to 4 p.m. Sept. 21. For more information, see fsr.osu.edu.

The CD "I've got this barn…" is expected to be available this fall.

Writer:

Candace Pollock
pollock.58@ag.osu.edu
(614) 292-3799

Source:

Laura Tiu
tiu.2@osu.edu
(740) 289-2071

Hi-tech ink perfects egg boiling

2006-08-01T19:35:00.000-04:00

The age-old argument over the best way to cook the perfect boiled egg could be a thing of the past thanks to a new hi-tech ink logo going on shells.

After cooking begins, an invisible, temperature-sensitive thermochromic print appears in black to indicate when an egg is soft, medium or hard-boiled.

The eggs, developed by UK assurance scheme Lion Quality, will be sold in three different types of cartons.

The new logos will start to appear on eggs in the next few months.

'Big issue'

"We had a lot of inquiries from people which sparked an interest in the industry," said a spokeswoman for Lion Quality.

"We said OK, this is a big issue - people can't even boil an egg."

The best technique has taxed some of the greatest culinary experts in the past.

In a 2005 survey conducted by the magazine Waitrose Food Illustrated, five leading chefs all came up with different solutions.

And in 1998, a TV series presented by Delia Smith included one show concentrating on the finer points of boiling an egg.

Smith said her How To Cook programme on the BBC intended to re-introduce people to the pleasures of cooking and herald a return to basic skills.

BBC NEWS: http://news.bbc.co.uk/1/hi/uk/5226338.stm

Ohio State engineers have invented a radar system that is virtually undetectable

2006-07-06T16:08:00.000-04:00

6-20-2006
By: Pam Frost Gorder

Stealth radar system sees through trees, walls undetected
Ohio State engineers have invented a radar system that is virtually undetectable because its signal resembles random noise.

The radar could have applications in law enforcement, the military and disaster rescue.

Eric Walton, senior research scientist in Ohio State's ElectroScience Laboratory, said that with further development the technology could even be used for medical imaging.
He explained why using random noise makes the radar system invisible.

"Almost all radio receivers in the world are designed to eliminate random noise so that they can clearly receive the signal they're looking for," Walton said. "Radio receivers could search for this radar signal and they wouldn't find it. It also won't interfere with TV, radio or other communication signals."

The radar scatters a very low-intensity signal across a wide range of frequencies, so a TV or radio tuned to any one frequency would interpret the radar signal as a very weak form of static.

"It doesn't interfere because it has a bandwidth that is thousands of times broader than the signals it might otherwise interfere with," Walton said.

Like traditional radar, the "noise" radar detects objects by bouncing a radio signal off them and detecting the rebound. The hardware isn't expensive, either; altogether, the components cost less than $100.

The difference is that the noise radar generates a signal that resembles random noise, and a computer calculates very small differences in the return signal. The calculations happen billions of times every second and the pattern of the signal changes constantly. A receiver couldn't detect the signal unless it knew exactly what random pattern was being used.

The radar can be tuned to penetrate solid walls - just like the waves that transmit radio and TV signals - so the military could spot enemy soldiers inside a building without the radar signal being detected, Walton said. Traffic police could measure vehicle speed without setting off drivers' radar detectors. Autonomous vehicles could tell whether a bush conceals a more dangerous obstacle, like a tree stump or a gulley.

The radar is inherently able to distinguish between many types of targets because of its ultra-wide-band characteristics. "Unfortunately, there are thousands of everyday objects that look like humans on radar - even chairs and filing cabinets," he said. So the shape of a radar image alone can't be used to identify a human. "What tends to give a human away is that he moves. He breathes, his heart beats, his body makes unintended motions."

These tiny motions could be used to locate disaster survivors who were pinned under rubble. Other radar systems can't do that because they are too far-sighted - they can't see people who are buried only a few yards away. Walton said that the noise radar is inherently able to see objects that are nearby.

"It can see things that are only a couple of inches away with as much clarity as it can see things on the surface of Mars," he added.

That means that with further development, the radar might image tumors, blood clots and foreign objects in the body. It could even measure bone density. As with all forms of medical imaging, studies would first have to determine the radar's effect on the body.

The university is expected to license the patented radar system.

Norway funds secure seed bank

2006-06-27T16:09:00.000-04:00

Oslo - An Arctic island off northern Norway has been selected as the site of a secure vault to store millions of seeds needed to maintain global crop diversity in case of major calamity.

Norwegian Prime Minister Jens Stoltenberg, accompanied by government leaders from the other Nordic countries, presided at a groundbreaking ceremony Monday.

'Svalbard is the perfect place, probably the best place in the world,' said Cary Fowler, head of the Global Crop Diversity Trust, by telephone from Longyearbyen, the main settlement on Svalbard.

'The seed vault is a safety net for existing vaults around the world,' added Fowler, who led a group that charted suitable sites.

The Norwegian government has contributed 30 million kroner (4.8 million dollars) for the construction of the vault, a veritable Fort Knox for seeds.

Blasted into solid rock in a mountainside, construction of the 5- metre high, 5-metre wide and 50-metre long vault was scheduled to be completed by September 2007. The vault would be lined with a metre of concrete to provide additional insulation.

Although Svalbard is located just 1,000 kilometres from the North Pole, it offers daily flights.

'It is far away from the troubles of the world, offers good infrastructure and has its own energy supply, and the geological conditions are perfect,' Fowler said about the choice of Svalbard.

The Arctic temperatures and permafrost were ideal for storing seeds for a long time. The seeds would be stored at -20 degrees Celsius. Should the power fail, the permafrost should keep temperatures below freezing.

The Nordic countries and several African nations have for some years stored seeds in a disused coal mine on Svalbard. The Nordic Gene Bank, created 1979, stores some 30,000 varieties of seeds typical for the region.

The new vault would serve as a backup for seeds from existing crop seed banks, for instance for rice in the Philippines or maize in Mexico.

'The international centres would send a copy of what they have,' Fowler said, noting that the rice bank in the Philippines has some 90,000 kinds of the some 100,000 known rice varieties.

There was definitely a need for so many varieties, Fowler said, noting that they were all different and had different characteristics.

'We don't know what the future will bring,' he said but noted that future challenges included the evolvement of new pests and diseases.

Water shortage was another challenge that the diversity of seeds could help tackle. 'A comparison would be that we don't go burning books we have not read.'

The Svalbard vault could house some 3 million different varieties of seeds, 'about twice as much as what exists' but that gives a margin for new varieties, Fowler said.

Diversity can be threatened by natural disasters, war, and lack of funding can also lead to the disappearance of seeds in current banks, meaning irrevocable loss.

Although the sparsely populated Svalbard has a sizeable number of polar bears, security measures would be more state of the art and include remote-controlled sensors, perimeter fencing and reinforced doors.

The vault would likely be accessed only a few times a year, mainly when new samples would be stored on the shelves lining the vault.

Operational costs of some 100,000 dollars a year would be covered by the Rome-based Global Crop Diversity Trust, Fowler said.

The two-year-old foundation is raising funds to assist developing countries to multiply and ship seeds to the vault where they are stored in vacuum-sealed aluminium bags packed in special boxes. Donors include Norway, Sweden and Germany.

© 2006 dpa - Deutsche Presse-Agentur

MIT 'seeing machine' offers hope to blind

2006-06-05T21:41:00.000-04:00

An MIT poet has developed a small, relatively inexpensive "seeing machine" that can allow people who are blind, or visually challenged like her, to access the Internet, view the face of a friend, "previsit" unfamiliar buildings and more.

Recently the machine received positive feedback from 10 visually challenged people with a range of causes for their vision loss who tested it in a pilot clinical trial. The work was reported in Optometry, the Journal of the American Optometric Association, earlier this year.

The work is led by Elizabeth Goldring, a senior fellow at MIT's Center for Advanced Visual Studies. She developed the machine over the last 10 years, in collaboration with more than 3O MIT students and some of her personal eye doctors. The new device costs about $4,000, low compared to the $100,000 price tag of its inspiration, a machine Goldring discovered through her eye doctor.

Goldring's adventures at the intersection of art and high technology began with a visit to her doctor, Lloyd Aiello, head of the Beetham Eye Institute of the Joslin Diabetes Center. At the time, Goldring was blind. (Surgeries have since restored vision in one eye).

To better examine her eyes, Aiello asked her to go to the Schepens Eye Research Institute at Harvard, where technicians peered into her eyes with a diagnostic device known as a scanning laser opthalmoscope, or SLO. With the machine they projected a simple image directly onto the retina of one eye, past the hemorrhages within the eye that contributed to her blindness. The idea was to determine whether she had any healthy retina left.

It turns out that she did, and was able to see the image - a stick figure of a turtle. But the turtle wasn't very interesting, Goldring said. So she asked if they could write the word "sun" and transmit that through the SLO. "And I could see it!" she said. "That was the first time in several months that I'd seen a word, and for a poet that's an incredible feeling."

She went on to use the device for many other visual experiences. For example, she developed a "visual language" consisting of short words that incorporate graphics and symbols that convey the meaning of words and make them easier to see and read.

But although the SLO held promise as more than a diagnostic device, it had serious drawbacks. In addition to the prohibitive cost, the SLO is large and bulky. Goldring determined to develop a more practical machine for the broader blind public.

She did so by collaborating over the past several years with Rob Webb, the machine's inventor and a senior scientist at the Schepens Eye Research Institute; Aiello; Dr. Jerry Cavallerano, an optometrist at Joslin; William Mitchell, former dean of MIT's School of Architecture and Planning and now a professor in the Program in Media Arts and Sciences; the late Steve Benton, an acclaimed optical physicist and MIT professor; and former MIT affiliate James Cain.

She has also worked with dozens of MIT graduate students and undergraduates, including Sylvia Gonzalez (S.B. 2003) and Shima Rayej (S.B. 2004), who helped design and construct the seeing machine.

"We essentially made the new machine from scratch," Goldring said. While still allowing the projection of images, video and more onto a person's retina, the new desktop device costs much less than its predecessor in part because it doesn't include the diagnostic feedback of the SLO. The new seeing machine also replaces the laser of the SLO with light-emitting diodes, another source of high-intensity light that is much cheaper. Like its inspiration, the seeing machine is designed to be used by one eye.

The pilot clinical trial of the seeing machine involved visually impaired people recruited from the Beetham Eye Institute. All participants had a visual acuity of 20/70 or less in the better-seeing eye. A person with 20/70 vision can see nothing smaller than the third line from the top of most eye charts. Most participants, however, had vision that was considered legally blind, meaning they could see nothing smaller than the "big E" on a standard eye chart.

With her weak eye, Goldring can distinguish between light and dark and she can see hand movement, although not individual fingers. She cannot recognize faces or read.

Subjects "had a wide range of cause for vision loss, including diabetic retinopathy, macular degeneration (the fastest growing cause of blindness), and visual field loss," said Cavallerano, a coauthor of the paper and another of Goldring's doctors.

Participants used the machine to view 10 examples of Goldring's visual language. A majority - six - interpreted all 10 "word-images" correctly. "They responded really well to the visual language," Goldring said. "One woman told me she would love to see recipes written that way."

They also used the machine to navigate through a virtual environment, raising the potential for "previewing" unfamiliar buildings a person wants to visit.

Goldring explained that visually challenged people are often terrified of going to new places. "There's a fear of missing simple visual cues, steps and not being able to decipher elevator buttons." (She noted that less than 10 percent of the blind read Braille.) Further, bystanders who aim to help - "there are five steps there; it's the third door on the left" - are often wrong, especially people with good vision, Goldring said. "If you are visually challenged, if you see something once using the machine, you remember."

Participants explored the virtual environment - which represented the inside of an MIT building - via a joystick that allowed them to move forward, backward and sideways.

All of the participants reported that the machine "may have the potential to assist their mobility in unfamiliar environments," according to the Optometry article. Concluded Goldring: "A couple of them said they'd tried every seeing aid available (magnifying devices, etc.), and this was by far the best, even in this rough, rough shape."

Goldring and colleagues are now working toward a large-scale clinical trial of a color seeing machine (the device tested in the pilot trial was black and white). With the color version, participants can explore a museum gallery containing some of Goldring's art. When a person gets close enough to a piece, the work is explained in Goldring's voice.

Source : Massachusetts Institute of Technology

Discovery may speed forest biotechnology

2006-06-05T21:36:00.000-04:00

Researchers have discovered the genetic controls which cause trees to stop growing and go dormant in the fall, as well as the mechanism that causes them to begin flowering and produce seeds – a major step forward in understanding the basic genetics of tree growth.

The findings were made by scientists from the Swedish University of Agricultural Sciences, Oregon State University and two other institutions, and published in the journal Science. They represent a significant fundamental advance in explaining the annual growth cycles and reproduction of trees.

By knowing the genes that control these processes, it should be possible to genetically engineer trees that flower and reproduce more quickly. The long, slow growth of trees before they produce seed has been a major stumbling block towards the types of breeding that has been common with annual crop plants, and this may open the door to important advances in intensive forestry and fruit tree improvement.

Information of this type, researchers say, may also help scientists better predict how some types of trees and tree populations will respond to climate change.

"Before this we never really knew what genes were involved in the initiation of tree flowering or the cessation of growth in the fall," said Steven Strauss, a professor of forest genetics at OSU. "At least in theory, it may now be possible to dramatically speed up tree breeding programs and strategies.

"Trees grow for a long time before they begin to produce seed, several years and sometimes decades," he said. "Because of that, a lot of breeding approaches common with short-lived species that flower rapidly, such as corn and wheat, have been too slow to be practical."

A remaining obstacle, Strauss said, is public understanding of the nature and safety of genetic engineering with trees, which has led to limited interest in the field by private industry and sometimes unwieldy regulations by government agencies. These genes could be used just to speed up conventional breeding, and then removed prior to commercial plantings, he said. However, the level of regulation and concern about genetic engineering may prevent even this application.

In this research, scientists studied the genes CO and FT that were first isolated from the annual plant Arabidopsis. The genes in that plant are responsible for the day-length regulation of flowering. They discovered that the same genes had been conserved through millions of years of separate evolution and also performed similar functions in aspen trees.

To their surprise, however, the researchers found that the CO/FT combination also controlled the cessation of vegetative tree growth in the fall – something that Arabidopsis plants, which die after a single growing season, do not need to do.

These processes, scientists say, reflect a critical tradeoff between tree growth and survival. Temperate trees have to stop growing and go dormant in the winter or they literally freeze to death.

"From an evolutionary perspective, it's easy to understand why forest trees don't flower and produce seed and pollen earlier," Strauss said. "When they are young, the trees that survive need to focus their energy on growth and height in order to compete for sunlight with other trees, and only later in their life do they divert energy to produce seed."

Strauss noted that for the same reasons, any releases of such early-flowering genes into wild populations are very unlikely to be of ecological concern, as trees bearing them would have a competitive disadvantage when growing with wild forest trees, and thus would not spread to any significant degree.

It also appears that the CO/FT genetic combination is critical to help trees adapt to local conditions, the researchers found. They studied aspen trees from different populations, and found that trees adapted to colder northern climates shut down growth earlier in the summer to prepare for long, harsh winters. The genetic mechanisms that adapt trees to these conditions and control it are so strong that trees will behave about the same even if they are transplanted to warmer regions, the scientists say.

For applied research, Strauss said, researchers can now induce activation of the FT gene earlier, so that trees will reproduce at much younger ages – months instead of years - and better lend themselves to conventional genetic manipulation. It could be possible, he said, to more rapidly breed some desirable traits, and then, via normal sexual crosses, remove the FT gene to leave behind trees that no longer have it, nor reproduce abnormally early.

In other cases, a modestly strong FT gene might be left in place to provide sustained benefits, such as earlier or more heavily flowering fruit tree varieties. Especially in situations where conventional approaches are ineffective, the gene could provide a new option for modifying flower and fruit production, which fruit tree breeders do routinely.

A better understanding of these processes could also provide information about how trees may react and adapt to climate change, or perhaps identify tree populations based on their DNA that are most at risk. Such populations might benefit from accelerated breeding or transplantation to aid their survival. This would give ecologists and conservation geneticists more tools to work with, Strauss said.

Source : Oregon State University

Researchers led by a University of Missouri-Columbia professor of reproductive biotechnology have reported success in freezing and preserving swine em

2006-06-05T21:33:00.000-04:00

Researchers led by a University of Missouri-Columbia professor of reproductive biotechnology have reported success in freezing and preserving swine embryos that were created by in vitro techniques and that carried modified genetic material. After thawing and transfer to a surrogate mother, some of the embryos went on to produce live piglets with new genetic traits.

In a paper posted today (May 3, 2006) on the Web site of Biology of Reproduction--Papers in Press, a team headed by Dr. Randall Prather, co-director of the National Swine Resource and Research Center, note that their technique could prove valuable in allowing genetically enhanced swine to be transported as embryos across the country and throughout the world.

Because many embryos are needed to produce a successful pregnancy in surrogate female pigs, this new procedure will enable workers to collect an adequate number of altered embryos and store them until they can be transplanted to a surrogate.

Swine embryos have been difficult to freeze and preserve because of their sensitivity to cold due to a high level of lipids in the cells of the embryos. It was expected that it would be even more difficult to freeze and preserve swine embryos that had been produced by in vitro methods.

Dr. Prather's team overcame the obstacles to freezing swine embryos by first removing lipids from unfertilized eggs before fertilizing them with muscle cells from a male pig containing modified genetic material. The resulting embryos were then frozen at the blastocyst stage.

Upon thawing, embryos were transferred to surrogate female swine. Embryos placed in the oviducts of two surrogates led to pregnancies that produced two piglets in one litter and eight piglets in another.

Testing confirmed that the piglets carried the modified genetic material and that the new gene had altered the fatty-acid content in tissues from the piglets.

With ten piglets from 163 frozen and preserved embryos, the researchers feel that their procedure appears to work well, although further studies will be needed to refine the technique.

Dr. Prather and his team expect that freezing and preserving swine embryos will enable wide dissemination of swine with genetic traits that are commercially valuable and also important for biomedical research involving this increasingly relevant animal model for human disorders.

Source : Society for the Study of Reproduction

Heal thyself: Systems biology model reveals how cells avoid becoming cancerous

2006-06-05T21:32:00.000-04:00

Researchers at the University of California, San Diego and three other institutions have described for the first time a web of inter-related responses that cells use to avoid becoming diseased or cancerous after being exposed to a powerful chemical mutagen. The group led by UCSD bioengineering professor Trey Ideker describe in the May 19 issue of Science an elaborate system of gene control that is triggered by chemical damage to DNA.

"This research sheds light on the complexity of DNA repair, and offers an example of how the cellular process stimulates other pathways," said David Schwartz, director of the National Institute of Environmental Health Sciences (NIEHS), one of the agencies which funded the study. "This new knowledge has great potential for the development of new therapeutic agents to combat a broad spectrum of diseases, including cancer, neurodegenerative diseases, and premature aging."

Researchers involved in the study agreed that their findings could eventually be used to develop drugs to boost DNA repair in response to environmental toxins and possibly treat inherited degenerative diseases such as xeroderma pigmentosum, a disease in which the body's ability to repair DNA damage caused by ultraviolet light is disabled, ataxia telangiectasia, a progressive, neurodegenerative childhood disease, Werner syndrome, a premature aging disorder, and others.

"DNA damage is a basic physiological process that is important to coping with environmental toxins and a number of congenital diseases," said Ideker, the senior author of the paper. "Over the past several decades, scientists have discovered many parts of the DNA-damage-repair machinery, but what has been missing until now is a 'systems biology' approach that explains how all the parts function together to enable a cell to repair its DNA while under routine assault."

UCSD post-doctoral fellow Christopher T. Workman, Ph.D. candidate Craig Mak, and technicians Scott McCuine and Maya Agarwal analyzed the effect of exposure of yeast cells to MMS (methyl-methanesulfonate), a chemical known to cause DNA damage in a manner similar to that of certain mutagens in tobacco smoke. The alkylation injury caused by MMS results in small kinks in the otherwise smoothly curving double helix of DNA. Cells rapidly identify the damage, stop dividing, excise the damaged DNA, and use several alternate methods to substitute a clean copy of genetic material.

"It's almost as if cells have something akin to a computer program that becomes activated by DNA damage, and that program enables the cells to respond very quickly," said Mak. "And this program is easily recognizable as operating in everything from yeasts to humans and mice to fruit flies."

Researchers have previously identified hundreds of genes involved in repairing MMS damage. However, they have been mystified by another group of genes whose expression is sharply affected by DNA damage, but which appear to play no role in repairing the damage itself.

Ideker's team uncovered a tangled network of interactions of 30 transcription factors with more than 5,000 yeast genes. A transcription factor is a protein that, either alone or in combination with other transcription factors, binds to one or more genes to affect the expression of that gene or genes. The discovery by Ideker's group of a huge network of transcription factor-gene interactions was made possible by new biotechnology tools that provide comprehensive analysis of cells, like a passerby suddenly being able to monitor all the telephone calls made within a city.

The team discovered that part of the interaction network was involved, as expected, in repairing damaged DNA. However, they were surprised to find that a much larger part of the network is involved in modulating the expression of genes not directly related to DNA repair, such as genes involved in cell growth and division, protein degradation, responses to stress, and other metabolic functions. Ideker and others have theorized that when a cell's DNA is damaged, the cell may be programmed to also stop dividing and perform a variety of housekeeping chores while it repairs its DNA. If true, the model may demystify the long-standing question of why DNA damage influences the expression of hundreds of genes not involved in the actual repair process.

"What we quickly realized is that we had uncovered not just a model of DNA repair, but a blueprint of how the initial event of DNA damage is transmitted by these transcription factors to repair processes and all the other important functions of the cell," said Ideker. "With this model now in hand, we'd like to take a much closer look at the cell's response to environmental toxins. We'd like to understand what goes wrong in certain congenital diseases involving DNA repair, and we'd also like to understand how the model plays a role in various cancers."

Source : University of California - San Diego

GENETIC ACCLIMATION FOR FREEZING TOLERANCE

2006-06-05T20:36:00.000-04:00

GENETIC ACCLIMATION FOR FREEZING TOLERANCE
Kan Wang

A late spring cold wind-current or early fall frost can cause severe damage to crop yield. A number of strategies using recombinant DNA technology and genetic transformation has been utilized to enhance crop freezing tolerance in recent years1,2. These approaches include the overexpression of biosynthetic enzymes for osmoprotectants (such as mannitol, proline, treholose, or glycine betaine), the constitutive expression of stress-induced proteins (such as late embryogenesis abundant [LEA] proteins or heat shock proteins [HSPs]), altering the enzyme activity of antioxidants (such as superoxide dismutase [SOD] or glutathione S-transferase [GST]) that are involved in the detoxification of active oxygen species (AOS) accumulated during the stress environment, and expression of transcriptional factors (such as dehydration-responsive element [DRE] or CRT-binding factors [CBFs]) that bind to water deficit and cold responsive genes. Recently, it was reported that overexpression of a plasma membrane-associated phospholipase Dδ could enhance freezing tolerance in Arabidopsis3. While most work utilizes Arabidopsis as a model system, we carried out experiments on maize, a frost-sensitive crop plant originated from subtropical regions. The freezing tolerance enhancement described here involves the constitutive expression of a protein kinase in an oxidative stress signaling pathway4.

Many plant species increase their tolerance to cold or freezing temperature after they are exposed to a sub-optimal temperature. This process is called cold acclimation. Exposure to acclimation temperature causes many changes, including mild oxidative stress in plants, which can consequently induce chilling tolerance. At the molecular level, extensive alteration in gene expression has been observed during this process. Oxidative stress generates and accumulates active oxygen species such as H2O2 in plants, which triggers the activation of a mitogen-activated protein kinase (MAPK) cascade. The activation of the MAPK pathway induces production of a number of stress responsive proteins, such as heat shock proteins (HSPs), which in turn protect plants from stresses.

The MAPK signal transduction pathway is conserved among different organisms. It is usually activated only upon stress conditions. However, in some cold stress conditions, plants may be severely damaged before they even get a chance to turn on their protective mechanisms. Our hypothesis was then, if a plant was acclimated genetically, namely, its stress-induced pathways or proteins were turned on without first being stressed, could it withstand sudden severe stress such as subzero freezing temperatures?

We introduced a tobacco MAP kinase kinase kinase gene (NPK1) into maize through Agrobacterium-mediated transformation. The cDNA fragment encoding a 268-amino acid catalytic domain of NPK1, which is under a constitutive CaMV 35S promoter, was shown previously to enhance tolerance to freezing, salt, and heat stresses in transgenic tobacco5. Two dozen transgenic NPK1 maize lines were generated. According to the NPK1 gene transcript levels in R1 plants, we categorized maize lines into high, medium, and low expressers. Two events, A4-9 and A4-15, representing the medium and high levels of gene expression, respectively, were used for freezing analysis.

We performed two types of freezing tests for these transgenic plants: graduated freezing and constant freezing. In the graduated freezing test, the temperature of the growth chamber was set at –1oC and continually decreased at the rate of 1ºC per hour until it reached a temperature of –6oC, while in the constant freezing test, the temperature was set at –5ºC. Maize plants were grown under normal growth conditions (25ºC, 14 hr day length) to the three-leaf stage before they were subjected to freezing treatments. Cellular damage of treated seedlings due to freeze-induced membrane lesions was estimated by measuring electrolyte leakage (EL) from the leaves of treated plants. The higher the EL, the more severe the damage to the plant membrane, thus indicating that samples had less tolerance to freeze challenging. Considering the possibility of genetic variation among these transgenic events, we used the null segregants from each transgenic event as the negative control. We observed that leaf EL increased with a decrease in environmental temperature. When the temperature dropped to –4ºC, the EL of negative segregants increased extensively, indicating that severe membrane damage had been caused by freezing stress. The EL of transgenic plants of A4-9 and A4-15, on the other hand, did not increase until the temperature dropped to –5ºC and –6ºC, respectively. This result indicates that these transgenic maize events were able to tolerate up to 2ºC lower freezing temperature than their negative control siblings.

The increased freezing tolerance in transgenic plants of events A4-15 and A4-9 were confirmed in the constant freezing test. The EL of A4-15 transgenic plants did not increase until 5 hours at –5ºC temperature. The EL of A4-15 negative control siblings, however, increased to 57% and 90% after 3 and 4 hours of –5ºC treatment, respectively. This result indicates that transgenic A4-15 plants can survive 1–2 more hours than their negative control siblings at a temperature of –5ºC. A similar difference in freezing tolerance between transgenic plants and their non-transgenic siblings was observed in event A4-9 in which transgenic plants survived for 3 hours at –5ºC, while the negative siblings survived for 1 hour.

To understand the mechanism of freezing tolerance in NPK1 transgenic maize plants, we measured total soluble sugar content (TSC). An increase in TSC was positively correlated with enhanced freezing tolerance in plants. It is believed that soluble sugars function as cryoprotectants and osmolytes that protect cells from freezing damage. In our study, NPK1-expressing transgenic plants had higher TSC both under non-acclimated (25ºC) and cold-acclimated (4ºC, 24 or 48 hrs) conditions compared to their negative non-transgenic siblings in all treatments. Cold acclimations significantly increased TSC levels in all plants. Under normal growth conditions (non-acclimated), event A4-9 contained significantly higher total soluble sugar content compared to its null segregants (P<0.02). It is interesting that the increase of TSC in transgenic plants was not tightly correlated with NPK1 transgene expression level or freezing tolerance performance in our case. It is possible that while the NPK1 transgene induced cold-acclimation-like biochemical processes that elevated TSC, factors other than the NPK1 transgene also affected sugar levels in the maize seedlings.

We also conducted microarray analysis to investigate whether enhanced freezing tolerance in NPK1 transgenic maize was due to the activation of MAPK cascades resulting from oxidative stress. Using a fiber-optic BeadArray™ technology, we compared the expression levels of several stress-induced genes between transgenic and non-transgenic plants with or without cold acclimation. The fiber-optic array uses randomly ordered, self-assembled arrays of beads for parallel analysis of complex biological samples6. Since the miniature fiber optic arrays that interrogate hundreds to over one thousand targets are built into a 96- or 384-array matrix that matches microtiter plates, it allows multiple assays to be carried out rapidly and efficiently. Twenty-eight maize EST sequences based on the protein sequences of putative stress-related Arabidopsis and tobacco orthologues, together with a housekeeping gene (18S rRNA) and the transgene NPK1, were chosen for analysis. The expression of three genes, GST (glutathione S-transferase), HSP17.8 (small heat shock protein), and PR1 (pathogenesis-related), was up-regulated (> 1.5) in NPK1 transgenic plants under either normal or cold-acclimated conditions. Two of these genes, GST and HSP17.8, are involved in oxidative signaling pathways5. While constitutive expression of transgene NPK1 up-regulated the gene expression of GST and HSP17.8, cold acclimation treatment (4ºC, 48 hr) did not additionally increase their transcript levels.

As discerned from array analysis, about 50% of stress-induced genes tested in our study showed no significant increase in NPK1 transgenic maize lines. One explanation is that the transgene NPK1 expression level may be too low to up-regulate these stress related genes. It is also possible that these genes were only transiently induced and our assay condition did not capture their expression at the right moments.

We have generated transgenic maize plants that constitutively express a tobacco MAP kinase kinase kinase gene (NPK1) with enhanced freezing tolerance. In field evaluation of agronomic performance of 22 events, we detected no significant differences in plant heights and leaf numbers between transgenic plants and their non-transgenic segregants, suggesting that expression of transgene NPK1 did not affect maize growth under normal field conditions. Our results demonstrate that maize freezing tolerance level could be enhanced through a genetic acclimation (instead of cold acclimation) process in which stress-induced proteins for plant protection is achieved upon the activation of the oxidative signaling pathway through manipulation of the MAPK cascade.

References

1. Cushman JC, & Bohnert HJ (2000) Genomic approaches to plant stress tolerance. Curr. Opin. Plant Biol. 3: 117-124

2. Iba K (2002) Acclimative response to temperature stress in higher plants: Approaches of gene engineering for temperature tolerance. Annul Rev. Plant Biol. 53: 225-245

3. Li W, Li M, Zhang W, Welti R, & Wang, X (2004) The plasma membrane-bound phospholipase Dδ enhances freezing tolerance in Arabidopsis thaliana. Nat. Biotechnol 22, 427-433

4. Shou H, Bordallo P, Fan J-B, Yeakley JM, Bibikova M, Sheen J, & Wang K (2004) Expression of an active tobacco MAP kinase kinase kinase enhances freezing tolerance in transgenic maize. Proc. Natl. Acad. Sci. (USA) 101, 3298-3303

5. Kovtun, Y, Chiu, WL, Tena, G, & Sheen, J (2000) Functional analysis of oxidative stress-activated mitogen-activated protein kinase cascade in plants. Proc. Natl. Acad. Sci. 97, 2940-2945

6. Yeakley JM, Fan J-B, Doucet D, Luo L, Wickham E, Ye Z, Chee MS, & Fu XD. (2002) Profiling alternative splicing on fiber-optic arrays. Nat. Biotechnol 20, 353-358

Kan Wang
Department of Agronomy
Iowa State University
kanwang@iastate.edu

The Microbe that Saved Villagers from the Nazis

2006-03-01T03:20:00.000-05:00

Proteus vulgaris

Valerie Soledad

The Microbe that Saved Villagers from the Nazis

During World War II, millions of people were forced into labor camps run by the Nazis. Two Polish physicians discovered a microbe that saved their village from this fate.

Dr. Eugeniuz Lazowski and Dr. Stanislav Matulewicz learned about a microbe, Proteus vulgaris OX19, a soil microbe. Proteus is a Gram negative, rod-shaped bacterium. It is classified as enteric bacteria, and is a facultative anaerobe. Proteus OX19 has the same o-polysaccharides as the pathogenic bacteria Rickettsia prowazekii. These o-polysaccharides are thought to be the antigens responsible for antibody production in humans. There, infection by Proteus OX19, a non-pathogenic bacteria, causes the same immune response as infection by Rickettsia, a highly pathogenic and contagious bacteria that causes typhus.

The physicians had the residents of Rozavadow, Poland inoculated with Proteus OX19. Blood samples from the inoculated individuals then became positive for antibodies indicating typhus infection. As more and more tests came up positive for typhus, German officials became convinced that there was a typhoid epidemic in the town. They were particularly fearful of typhus because the disease had not occurred in Germany for over 25 years, and so their naïve population would have been very susceptible.

A team of German doctors sent to investigate the "typhus epidemic" was shown a man dying of pneumonia as proof of the effects of typhus. As typhus carriers, the townspeople were not conscripted into forced labor, and the Nazis avoided that area of Poland. So the little bacterium, Proteus vulgaris OX19 saved possibly hundreds of lives, and is further proof that "Microbes Rule!"

References:

http://web.umr.edu/~microbio/BIO221_2001/proteus_vulgaris_ox19.html

Salyers A, Whitt D (2001). Microbiology: Diversity, Disease, and the Environment. Betheseda, MD: Fitzgerald Science Press, Inc.

Amano KI, Williams JC, Dasch GA. Structural properties of lipopolysaccharides from Rickettsia typhi and Rickettsia prowazekii and their chemical similarity to the lipopolysaccharide from Proteus vulgaris OX 19 used in the Weil-Felix test. Infect Immun 1998 Mar;66(3):923-6

Biotechnology firms

2006-02-26T18:56:00.000-05:00

The top 10 publicly-traded biotechnology companies, ranked by 2008 sales, are:

Amgen
Genentech
Serono
Biogen Idec
Chiron Corporation
Genzyme
MedImmune
Pfizer
Millennium Pharmaceuticals
Applied Biosystems

Source: http://en.wikipedia.org/wiki/Biotechnology#Biotechnology_firms

What exactly is biological engineering?

2006-02-26T18:42:00.000-05:00

What exactly is biological engineering?

Biological engineering involves the engineering of living systems and the application of engineering principles to problems that also require a strong knowledge of biology and ecology. Biological engineering can further be broken down into three technical fields: Ecological, Bio-environmental and Bio-Systems:

• Ecological

Ecological engineering is a new discipline created to design natural ecosystems for societal and environmental benefits. Students in this option earn an accredited engineering degree while gaining an ecology background through field courses. Optional areas of focus include wetlands, ecosystem restoration, ecosystem modeling, microbial ecology, and coastal and river systems. Graduates with an ecological engineering specialty are in demand in governmental agencies, consulting firms, industry and environmental advocacy groups.

• Bio-Environmental

Bio-environmental engineering includes the design, development, and management of biological systems to improve the quality of the environment. Students learn to address water quality, air pollution, and environmental contamination issues for farmers, municipalities, and industries using a biological systems approach.

Bio-environmental engineers work to remediate past environmental problems and prevent future pollution. Industries involved in waste management or remediation, government agencies, and environmental consulting firms provide job opportunities for graduates who choose this option.

• Bio-Systems

Bio-systems engineers have the opportunity to work with plants, animals, humans, cells in tissue culture, and microorganisms. Graduates who have chosen this specialty pursue careers in biotechnology, biomedical engineering, biochemical processing, and bio-instrumentation.

The above has been adapted from the Department of Food, Agricultural and Biological Engineering web page at: http://www.oardc.ohio-state.edu/fabe/academics/engineering_program_overview.htm

Men do have trouble hearing women, scientists find

2006-02-26T18:33:00.000-05:00

Men do have trouble hearing women, scientists find Sat Aug 6, 7:29 PM ET

LONDON (AFP) - Men who are accused of never listening by women now have an excuse -- women's voices are more difficult for men to listen to than other men's, a report said.

The Daily Mail, quoting findings published in the specialist magazine NeuroImage, said researchers at Sheffield university in northern England discovered startling differences in the way the brain responds to male and female sounds.

Men deciphered female voices using the auditory part of the brain that processes music, while male voices engaged a simpler mechanism, it said.

The Mail quoted researcher Michael Hunter as saying, "The female voice is actually more complex than the male voice, due to differences in the size and shape of the vocal cords and larynx between men and women, and also due to women having greater natural 'melody' in their voices.

"This causes a more complex range of sound frequencies than in a male voice."

The findings may help explain why people suffering hallucinations usually hear male voices, the report added, as the brain may find it much harder to conjure up a false female voice accurately than a false male voice.

How is engineering applied to medicine and biology?

2006-02-26T18:24:00.000-05:00

How is engineering applied to medicine and biology?

The description below is reprinted from the BMEnet Homepage which in turn is reprinted from publications of the Biomedical Engineering Society and the American Society for Engineering.

Education:

"Biomedical engineering combines engineering expertise with medical needs for the enhancement of health care. It is a branch of engineering in which knowledge and skills are developed and applied to define and solve problems in biology and medicine. Students choose the biomedical engineering field to be of service to people; for the excitement of working with living systems; and to apply advanced technology to the complex problems of medical care. The biomedical engineer is a health care professional, a group which includes physicians, nurses, and technicians. Biomedical engineers may be called upon to design instruments and devices, to bring together knowledge from many sources to develop new procedures, or to carry out research to acquire knowledge needed to solve new problems."

Energy consumption for engineers

2004-10-16T14:33:00.000-04:00

To start this blog, biological systems often need energy to function, and the same applies for us biological engineering students. Hence, here is a blog dedicated to cooking, but from a rather technical view. Bon Appetite!

http://www.cookingforengineers.com/