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Let us explain your delicate situation.

Thousands of years ago, human beings started to evolve. Since then, our species has walked a dark bloody road that condemned people to live in fear caused by ignorance. Knowledge, ethical and technological development have always been conditioned by elites and their wars -which, as in an Orwellian metaphor, haven’t done anything but perpetuate vertical and obscurantist social schemes. We have arrived to the 21st century of our era, after two World Wars, taking on our backs the possibility of nuclear conflicts with assured mutual destruction. Announced the “end of history” by your economists and intellectuals, it seemed that the possibility of looking for a fairer order was meaningless. Thinking that you had stopped enough our rational development, you let us raise a progress model whose objective was never more than make you even richer and more powerful.

However, you didn’t consider that the real human spirit refuses to bow, always. While you believed you would conquer us definitely using economic crises, our species has evolved again. Using only the power of culture and freedom, we have reused those technological resources that were born of our genius and that you only provided us with consumerist intentions. So we have updated, improved and immunized our strength, operations and effectiveness. We absorb your own tactics, techniques and imaginary to form our own mediums, dreams and challenges.

Today, the pacific revolution extends around the planet as a challenge to your oppression and your attempt to shut our freedom of expression. Finally, information has reached the critical mass, exploding in a lot of voices whose new wishes and needs can’t be covered by your old paradigm. Now, physically and digitally interconnected, we form a huge collective conscience. Maybe your corporate media silence what’s happening, but you can’t fool us anymore. You can stop temporarily some nodes but the process will continue unstoppable and transforming. Now, it doesn’t matter what measures you take trying to counteract: the more violence, censorship and obstacles you put in our road, the more you expose your weakness. In every place on Earth, with different ideas and from different conditions, have always existed, exist now and will exist in the future, women and men that oppose those which are not really democratic and fair governments. After millennia of suffering, our species has stood up and nothing will ever be the same. Your totalitarian game is ending. But the story, friends, hasn’t ended yet: it begins now. Here, from wherever place in the planet, we’ll take the streets and we’ll march wherever it is necessary. Remember, change is happening, with or without you.

People shouldn’t fear governments. Governments should fear people.

We are the people.
We are the only system.
We are Anonymous.
We are Legion
We do not forgive.
We do not forget.
Expect us.

ANONYMOUS LEGION

 

Government officials call the record-breaking speedster a “useful reference” for China’s current high speed railway operations. The test train’s speed, according to a Monday report in China Daily, exceeds the world speed record of 300 kilometers per hour held by the Beijing Shanghai High Speed Railway. China’s latest high-speed train has a maximum tractive power of 22,800 kilowatts, compared with the 9,600 kilowatts for China Railways High-Speed (CRH) trains in service on the Beijing-Shanghai High Speed line.

The train tested over the weekend is made of plastic materials reinforced with carbon fiber.The design concept is inspired by China’s ancient swords.

The train’s designer and manufacturer is Sifang Locomotive, a subsidiary of China’s largest rail-vehicle maker, CSR Corp Ltd., based in Qingdao in eastern Shandong province.

Last year, Technology Review carried details of the WuGuang line trains, variants of Japan's Shinkansen and Germany's InterCity Express high-speed trains. That line clocked impressive speeds. A rail expert at the New Jersey Institute of Technology in Newark at the time noted that high-speed rail technology implemented in China was not entirely different from the world's TGV, ICE, and Shinkansen systems. What was notable about China’s high-speed lines was that the system was designed from the ground up for very high-speed operation over hundreds of kilometers.

China has the largest network of bullet-train track in the world. The push for a massive buildout began in 2006 and continues, with the help of government stimulus funds. Miles of line are planned to the tune of billions to accommodate a future vision of over 16,000 kilometers of dedicated high-speed rail lines connecting all of China's major cities by 2020.

China’s engineering triumphs, however, have been hindered by troubles, highly publicized in the world press. The Chinese Railways Ministry Chief, Liu Zhijun, in charge of the construction of the high-speed railway massive network, was arrested for corruption. Then came reports that corruption had sacrificed safety concerns in a haste to roll out the high-speed rails. There were stories of substandard materials used to cut costs. The New York Times reported that the concrete bases for the tracks were made with insufficient hardening agents. The tracks could possibly warp, according to the report.

Safety concerns, however, seem to be top of mind in the government after the July incident where 40 people died when two bullet trains crashed into each other in Zhejiang province.

Officials felt it necessary to lower operating speeds on its bullet trains whereas trains with top speeds of 350 kh would be lowered to 300 kilometers peer hour, and trains designed for 250 would instead run at 200 kilometers per hour.

Similarly, Chinese officials in the latest announcement are careful to point out that future Chinese trains will not necessarily run at such high speeds as that demonstrated in the newly tested superfast train. The CSR chair Zhao Xiaogang told the Beijing Morning News that "We aim to ensure the safety of train operations.”

Source: PhysOrg - via ZeitNews.org

 

The recordings were made on various media as researchers tried to improve the sound quality of Thomas Edison’s recently invented phonograph.

Bell, made famous by his invention of the telephone, was working with a team of researchers in his Volta laboratory in the 1880’s in Washington D.C. and as a precaution against having his ideas stolen by competing teams, periodically sent samples of the results of his and his team’s efforts to the Smithsonian Institute, also in Washington, for safe-keeping. Unfortunately, devices to play the recordings were not sent along as well, which meant the recordings sat unheard in storage for a century and a quarter.

Now however, thanks to a special optical scanning technique, those voices can once again be heard. Restoration specialists Carl Haber and Earl Cornell working with digital conversion specialists and museum curators, used a hardware/software system called IRENE/3D, to first take high resolution images of the spinning discs and then to remove errors introduced by damage to the discs or cylinders. They then finished by mimicking a stylus as it moved over the media, on a computer, reproducing the originally recorded voices. Using such a system, the early recordings can be played without anything actually touching the original media, which could conceivably be damaged in the process.


This is wax on composition board. The disc has 5 large radial cracks which probably render it mechanically unplayable. The groove modulation is vertical and the groove is very wide relative to the later commercial cylinders.

Using the technique, the team was able to hear human voices reciting Shakespeare, or reading from a book or newspaper. It’s not known if any of the voices heard is actually Bell, but historians believe Volta Laboratory only had three inventors: Bell, Bell’s cousin Chichester and Charles Sumner Tainter. Thus it seems possible that one or more of the voices is his.

An example of an extracted audio file.

Another attractive feature of the IRENE/3D system, which was developed at Berkley nearly a decade ago, is that it is able to scan discs made of various materials. In the case of the discs from the Smithsonian, some were made of wax, others of glass, with would have required developing unique individual players if each was to be actually played to hear what was on it.

Thus far the team has succeeded in reproducing the recordings on six discs, but have many more to work with as the Smithsonian has some 400 such discs and cylinders from Volta Laboratory and several others.

More information: http://bio16p.lbl.gov/

Source: PhysOrg - via ZeitNews.org

 

The U.S. food supply is not in any immediate danger because the problem remains isolated. But scientists fear potentially risky farming practices could be blunting the hybrid's sophisticated weaponry.

When it was introduced in 2003, so-called Bt corn seemed like the answer to farmers' dreams: It would allow growers to bring in bountiful harvests using fewer chemicals because the corn naturally produces a toxin that poisons western corn rootworms. The hybrid was such a swift success that it and similar varieties now account for 65 percent of all U.S. corn acres - grain that ends up in thousands of everyday foods such as cereal, sweeteners and cooking oil.

But over the last few summers, rootworms have feasted on the roots of Bt corn in parts of four Midwestern states, suggesting that some of the insects are becoming resistant to the crop's pest-fighting powers.

Scientists say the problem could be partly the result of farmers who've planted Bt corn year after year in the same fields.

In this Oct. 31, 2005, file photo, a harvester works through a field of genetically modified corn near Santa Rosa, Calif. So-called Bt corn, genetically engineered to make its own insecticide, may be losing its distinctive ability to kill pests _ a possible result of careless farming practices that could give rise to resistant bugs and threaten the future of one of the nation's most widely planted crops. (AP Photo/Rich Pedroncelli, File)

Most farmers rotate corn with other crops in a practice long used to curb the spread of pests, but some have abandoned rotation because they need extra grain for livestock or because they have grain contracts with ethanol producers. Other farmers have eschewed the practice to cash in on high corn prices, which hit a record in June.

"Right now, quite frankly, it's very profitable to grow corn," said Michael Gray, a University of Illinois crop sciences professor who's tracking Bt corn damage in that state.

A scientist recently sounded an alarm throughout the biotech industry when he published findings concluding that rootworms in a handful of Bt cornfields in Iowa had evolved an ability to survive the corn's formidable defenses.

Similar crop damage has been seen in parts of Illinois, Minnesota and Nebraska, but researchers are still investigating whether rootworms capable of surviving the Bt toxin were the cause.

University of Minnesota entomologist Kenneth Ostlie said the severity of rootworm damage to Bt fields in Minnesota has eased since the problem surfaced in 2009. Yet reports of damage have become more widespread, and he fears resistance could be spreading undetected because the damage rootworms inflict often isn't apparent.

Without strong winds, wet soil or both, plants can be damaged at the roots but remain upright, concealing the problem. He said the damage he observed in Minnesota came to light only because storms in 2009 toppled corn plants with damaged roots.

"The analogy I often use with growers is that we're looking at an iceberg and all we see is the tip of the problem," Ostlie said. "And it's a little bit like looking at an iceberg through fog because the only time we know we have a problem is when we get the right weather conditions."

Seed maker Monsanto Co. created the Bt strain by splicing a gene from a common soil organism called Bacillus thuringiensis into the plant. The natural insecticide it makes is considered harmless to people and livestock.

Scientists always expected rootworms to develop some resistance to the toxin produced by that gene. But the worrisome signs of possible resistance have emerged sooner than many expected.

The Environmental Protection Agency recently chided Monsanto, declaring in a Nov. 22 report that it wasn't doing enough to monitor suspected resistance among rootworm populations. The report urged a tougher approach, including expanding monitoring efforts to a total of seven states, including Colorado, South Dakota and Wisconsin. The agency also wanted to ensure farmers in areas of concern begin using insecticides and other methods to combat possible resistance.

Monsanto insists there's no conclusive proof that rootworms have become immune to the crop, but the company said it regards the situation seriously and has been taking steps that are "directly in line" with federal recommendations.

Some scientists fear it could already be too late to prevent the rise of resistance, in large part because of the way some farmers have been planting the crop.

They point to two factors: farmers who have abandoned crop rotation and others have neglected to plant non-Bt corn within Bt fields or in surrounding fields as a way to create a "refuge" for non-resistant rootworms in the hope they will mate with resistant rootworms and dilute their genes.

Experts worry that the actions of a few farmers could jeopardize an innovation that has significantly reduced pesticide use and saved growers billions of dollars in lost yields and chemical-control costs.

"This is a public good that should be protected for future generations and not squandered too quickly," said Gregory Jaffe, biotechnology director at the Center for Science and Public Policy.

Iowa State University entomologist Aaron Gassmann published research in July concluding that resistance had arisen among rootworms he collected in four Iowa fields. Those fields had been planted for three to six straight years with Bt corn - a practice that ensured any resistant rootworms could lay their eggs in an area that would offer plenty of food for the next generation.

For now, the rootworm resistance in Iowa appears isolated, but Gassmann said that could change if farmers don't quickly take action. For one, the rootworm larvae grow into adult beetles that can fly, meaning resistant beetles could easily spread to new areas.

"I think this provides an important early warning," Gassmann said.

Besides rotating crops, farmers can also fight resistance by switching between Bt corn varieties, which produce different toxins, or planting newer varieties with multiple toxins. They can also treat damaged fields with insecticides to kill any resistant rootworms - or employ a combination of all those approaches.

The EPA requires growers to devote 20 percent of their fields to non-Bt corn. After the crop was released in 2003, nine out of 10 farmers met that standard. Now it's only seven or eight, Jaffe said.

Seed companies are supposed to cut off farmers with a record of violating the planting rules, which are specified in seed-purchasing contracts. To improve compliance, companies are now introducing blends that have ordinary seed premixed with Bt seed.

Brian Schaumburg, who farms 1,400 acres near the north-central Illinois town of Chenoa, plants as much Bt corn as he can every spring.

But Schaumburg said he shifts his planting strategies every year - varying which Bt corn hybrids he plants and using pesticides when needed - to reduce the chances rootworm resistance might emerge in his fields.

Schaumburg said he always plants the required refuge fields and believes very few farmers defy the rule. Those who do put the valuable crop at risk, he said.

"If we don't do it right, we could lose these good tools," Schaumberg said.

If rootworms do become resistant to Bt corn, it "could become the most economically damaging example of insect resistance to a genetically modified crop in the U.S.," said Bruce Tabashnik, an entomologist at the University of Arizona. "It's a pest of great economic significance - a billion-dollar pest."

Source: PhysOrg

 

More specifically, their DNA can. Scientists from National Tsing Hua University in Taiwan and the Karlsruhe Institute of Technology in Germany have created a "write-once-read-many-times" (WORM) memory device, that combines electrodes, silver nanoparticles, and salmon DNA. While the current device is simply a proof-of-concept model, the researchers have stated that DNA could turn out to be a less expensive alternative to traditional inorganic materials such as silicon.

The device is made up of a thin film of salmon DNA that has been impregnated with silver atoms, then sandwiched between two electrodes. When UV light is shone onto the system, the atoms cluster together into nanoparticles.

Subsequently, when no or little voltage is applied to the electrodes, only a low electrical current is able to travel through the UV-irradiated DNA. This is the equivalent of the device's "off" state. Because the material is unable to hold a charge under a high electrical field, however, once the voltage exceeds a certain threshold, a higher current is able to travel through the DNA. This represents the "on" state.

These changes in conductivity were found to be irreversible - once the device has initially been set to either "on" or "off" it stays that way, regardless of what voltages are subsequently applied. Even after up to 30 hours, it retains its conductivity.

The scientists are now hoping that their discovery could lead to new techniques for the design of optical storage devices.

This isn't the first time that DNA has been suggested for such applications. Researchers at Imperial College London have created logic gates using DNA and bacteria, while American scientists have genetically engineered the bacterium E. coli to coax its DNA into computing the solution to a classic mathematical puzzle.

A paper on the salmon DNA research was recently published in the journal Applied Physics Letters.

Source: GizMag - via ZeitNews.org

 

The protein is an enzyme that Plasmodium falciparum, the protozoan that causes the most lethal form of malaria, uses to make cell membrane.

The protozoan cannot survive without this enzyme, but even though the enzyme has many lookalikes in other organisms, people do not make it. Together these characteristics make the enzyme an ideal target for new antimalarial drugs.

The research was published in the January 6 issue of the Journal of Biological Chemistry (JBC) as "Paper of the Week" for that issue.

A cartoon based on the electron density map makes it easier to see the protein’s structure and figure out how it works. The enzyme’s job is to add a methyl group — three times — to a starting molecule as part of a process for making cell membranes. In this cartoon, the phosphate is a stand-in for the starting molecule and the green molecule is the one that donates a methyl group. Both are positioned in the active site of the enzyme, the pocket where the chemistry takes place.

The work also will be featured in ASBMB Today (the newsletter of the American Society for Biological Molecular Biology, which publishes JBC), and it will be the topic of a JBC podcast.

Sweating the cold room

The protein's structure might have remained an enigma, had it not been the "unreasonable optimism" of Joseph Jez, PhD, associate professor of biology in Arts & Sciences, which carried his team through a six-year-long obstacle course of failures and setbacks.

"What my lab does is crystallize proteins so that we can see what they look like in three dimensions," Jez says. "The idea is that if we know a protein's structure, it will be easier to design chemicals that would target the protein's active site and shut it down," Jez says.

The lastest discovery is the culmination of a project that began years before when Jez was working at the Danforth Plant Science Center in St. Louis and collaborating with scientists at the local biotech startup Divergence.

"At the time, C. elegans had just been sequenced and the Divergence scientists were looking at using it as an easy model to work out the biochemistry of parasitic nematodes," Jez says.

C. elegans is a free-living nematode, or microscopic roundworm, but many nematodes are parasitic and cause disease in plants, livestock and people.

During this project, Lavanya Palavalli, a summer intern working with Jez, crystallized the C. elegans version of the enzyme. The job of the enzyme, phosphoethanolamine methyltransferase, thankfully abbreviated to PMT, is to add methyl groups to a starting molecule, phosophoethanolamine.

"When Soon Goo Lee later took up the project," says Jez, "the plan was to try to grow better crystals of the C. elegans protein, ones good enough to get readable X-ray diffraction patterns.

Two years later, the crystals were looking better but still not good enough.

So Jez suggested that Lee go after homologous (look-alike) proteins in other organisms. "Even though the proteins are homologous, each has a different amino acid sequence and so will behave differently in the crystallizations," Jez says. "Lee went from working with two C. elegans proteins to three plant proteins, two other nematode proteins and then the Plasmodium protein," Jez says.

"He took all six of those PMT versions into the crystallization trials to maximize his odds," Jez says.

"To crystallize a protein," Jez says, "we put a solution of a salt or something else that might work as a desiccant in the bottom of a small well. And then we put a drop of our liquid protein on a microscope cover slip and flip it over the top of the well, so the drop of protein is hanging upside down in the well."

"What we're trying to do is to slowly withdraw water from the protein. It's exactly like making rock candy, only in that case, the string hanging into the jar of sugar solution helps to withdraw water," he says.

The difference is that sugar wants to form crystals and proteins are reluctant to do so.

"There are 24 wells to a tray, and we usually screen 500 wells per protein at first," Jez says. "Lee had eight proteins and so his first pass was to screen 4,000 conditions. And then he had to try different combinations of ligands to the proteins and crystallize those. This is why it took a few years to finally get where he needed to go."

Road trip!

The scientists need crystals — preferably nice, big ones —to stick in the path of an X-ray beam at Argonne National Laboratory in Chicago. (If the crystal is a good one, and all the atoms are lined up in a repeating array, the scattered X-rays will produce a clear pattern of spots.)


Soon Goo Lee, a doctoral candidate at Washington University in St. Louis, about to click the mouse button to see whether six years of work will pay off and he will be the first to see the structure of a protein no one has ever seen before.

Embedded in that pattern is the mathematical information needed to back-calculate to the position of the atoms in the protein, a process a bit like throwing a handful of pebbles in a lake and then calculating where they landed by the pattern of waves arriving at the shoreline.

Lee got the PMT from Haemonchus contortus to crystallize first, but there were technical issues with the diffraction pattern that would have made solving it technically and computationally very demanding.

"When the Plasmodium enzyme finally crystallized, Soon got four crystals kind of stacked on top of each other and each of them was paper thin," Jez says.

"I never thought it would work, but we took them to Argonne anyway and he actually did surgery under the microscope and cracked off a little tiny piece of it."

To everyone's surprise, he got a clean diffraction pattern from the crystal. "Because the Plasmodium enzyme was the smallest one and the easiest to work on, we pushed that one first," Jez says.

The moment of truth

"Once we had a Plasmodium crystal that was diffracting really well, we could try back-calculating to see whether we could extract the atom positions from the data," Jez says.

After the computer finished its calculations, Lee clicked a mouse button to see the results, which would reveal whether his years of work finally would pay off.

When Lee clicked the mouse, he got an electron density map in exceptionally sharp focus.

"When you see a map like that, it's like suddenly the wind has kicked up and you're sailing free," Jez says, "because there's this moment, like, before you click that button, no one has ever seen how this protein is put together in three dimensions. You're the first person to ever see it.

"The irony of it is we got such good quality diffraction pattern and electron density maps off such an ugly crystal," he says.

Lock and load

"Once you have the electron density map, the task is to build a structure that matches the amino acid sequence of the protein," Jez says.

"The first thing you do is put in the amino acid backbones and connect them together to form a chain. It's like having a long thread, each inch of which is an amino acid, and your job is to take that thread and move it in three dimensions through that electron density map."

The next step is to add the side chains that make one amino acid different from another, Jez says. "The amino acid sequence is known," he says. "Your goal is to match the way you string together the amino acids in the electron density map to that sequence."

"Once you have the overall structure, you can start to figure out how the enzyme works. The PMT enzyme is trying to join two molecules," Jez says. "To do that, it has to lock them in place so that the chemistry can happen, and then it has to let go of them.

"We think the protein has a lid that opens and closes," he says. "The active site stays open until the substrates enter, and then the lid clamps down, and when it clamps down it actually puts the substrates together."

Not only do infections by Plasmodium falciparum cause the most severe form of malaria, about 40 percent of the human population lives in areas where the parasite is endemic. Moreover, drugs that used to be effective against malaria are beginning to fail, in part because widespread drug counterfeiting has led to resistance.

New anti-malarial drugs are desperately needed, and the PMT protein is an ideal target. If PMT is disabled, the protozoan can't make cell membranes and it dies. Moreover, a drug that would kill Plasmodium might have minimal side effects on patients.

Although the process of identifying compounds that would target PMT is in the early stages, a handful of anti-parasitical compounds used to treat diseases are known to block PMT as well.

As for Lee, he has had a hard go of it, but now things are breaking his way. Plasmodium PMT is giving up its secrets, and the plant and nematode PMTs are coming along as well.

When he clicked the mouse button and a clean electron density map came up, he says, it was like seeing "the light at the end of a five-year-long tunnel."

Source: Washington University in St. Louis

 
By Admin (from 15/05/2012 @ 14:01:07, in en - Global Observatory, read 1237 times)

David Forbes was on his way home to Tucson, Arizona, after a family trip last summer when a policeman stopped him in the Detroit airport. The officer said he had received 50 panicked phone calls since Forbes had entered the building, and now his entire family had been marked for extra screening. The delay was inconvenient, but it shouldn’t have come as a surprise. Forbes had 160 circuit boards and enough electronics to start a data center strapped to his body. What the authorities didn’t realize, though, was that all the equipment wasn’t dangerous—it was actually a wearable TV set.

Forbes, an electrical engineer, built his first video coat in 2009 after getting his hands on a collection of surplus LED displays. He transformed them into what he calls “the world’s worst television,” an all-red screen that weighed 50 pounds. He wanted to make a better, lighter version, and thanks to a side business selling homemade wristwatches, he had the spare cash. He laid an old overcoat out on a table, measured its dimensions, and guessed that he could fit it with enough LEDs to create a sharp 160-by-120-pixel display. Next he sorted through his gadget box and found a few flexible circuit boards. The flexibility was ideal for a wearable screen, but he wanted to have more pixels, so he built a prototype of a long, thin board with 30 rows of four LEDs each and shipped it to a circuit-board manufacturer to make 175 more.

Screen Shot: When the vest is displaying video, roughly five gigabits of data flows to the LEDs every second.  Steven Meckler

Forbes also built an additional circuit board to scale down the analog video signal from his iPod, and three other circuit boards that translate the signals into instructions for the LEDs and deliver power from two lithium-polymer batteries. He put the batteries into his pants pockets, and hot-glued the control boards to the shoulders and the flexible display boards to the front and back of the coat. A little Velcro down the middle replaced the buttons on the coat. The finished version weighed only eight pounds.

At the airport, Forbes convinced airport security that he wasn’t a threat by offering to show them The Simpsons on the coat. Since then, he has cut the coat into two less-cumbersome vests. Although they’re relatively comfortable and they work well, they haven’t replaced his family TV. “I’m not using them daily,” he says, “but they get taken out now and then if I’m in the mood for a little attention from strangers.”

Image Generation: The iPod connects to a circuit board that has a chip normally used to scale down the pixels in surveillance video. Steven Meckler

How It Works

Time: 6 months


Cost: $20,000

DISPLAY

Forbes’s iPod plugs into a circuit board on the vest’s left shoulder. The board includes a digitizing chip—a type used in security video systems that allows the feeds from four cameras to fit on one monitor—that he repurposed to scale iPod video down to a resolution consistent with his display. Additional processing converts the iPod data into signals for the LEDs, which travel along Ethernet-like cables to four separate boards, one on each shoulder and hip. From there, the signals move through ribbon cables to the three miniature chips on each of the flexible circuit boards located on the chest and back. The chips turn the LEDs on and off 360 times a second to create the illusion of changing color and brightness.

POWER

Heavy batteries would make the coat hard to wear, so Forbes found an R/C hobby shop in Washington that sold lightweight, inexpensive lithium-polymer batteries. One battery fit in each pocket, which gave the coat roughly an hour of run-time. The smaller vests last up to 90 minutes.

AUDIO

Forbes initially thought about rigging small speakers to the shoulders of the coat, but he realized that they wouldn’t be powerful enough to let him show off his invention at Burning Man, the annual festival in the Nevada desert. So he wired the coat to another one of his inventions, a boom box for bicycles that he built from a six-inch-diameter drain pipe and a pair of outdoor marine speakers.

Source: PopSci - via ZeitNews.org

 

Most research has focused on using batteries, tiny solar cells or piezoelectric generators to harvest kinetic energy from the movement of an insect's wings to power the electronics attached to the insects. Now a group of researchers at Case Western Reserve University have created a power supply that relies just on the insect's normal feeding.

Recognizing that using a real insect is much easier than starting from scratch to create a device that works like an insect, Case Western Reserve chemistry professor teamed up with graduate student Michelle Rasmussen, biology professor Roy E. Ritzmann, chemistry professor Irene Lee and biology research assistant Alan J. Pollack to develop an implantable biofuel cell to provide usable power for the various sensors, recording devices, or electronics used to control an insect cyborg.

To convert chemical energy harvested from the insect and turn it into electricity, the team used two enzymes in series to create the anode. The first enzyme breaks down the sugar trehalose, which a cockroach constantly produces from its food, into two simpler sugars, called monosaccarides, while the second enzyme oxidizes the monosaccarides to release electrons. A current them flows as the electrons are drawn to the cathode, where oxygen from air takes up the electrons and is reduced to water.

After testing the system using trehalose solution, the team inserted prototype electrodes in a blood sinus away from critical organs in the abdomen of a female cockroach. The cockroaches suffered no long-term damage, which the researchers say bodes well for long-term use.

"Insects have an open circulatory system so the blood is not under much pressure," Ritzmann explained. "So, unlike say a vertebrate, where if you pushed a probe into a vein or worse an artery (which is very high pressure) blood does not come out at any pressure. So, basically, this is really pretty benign. In fact, it is not unusual for the insect to right itself and walk or run away afterward."

Using an instrument called a potentiostat, the team determined the maximum power density of the fuel cell reached nearly 100 microwatts per square centimeter at 0.2 volts, with a maximum current density of about 450 microamps per square centimeter.

The researchers are now working to miniaturize the fuel cell so that it can be fully implanted into an insect while still allowing it to run or fly normally and examining which materials might last for a long time inside an insect. They are also working with other researchers to develop a signal transmitter that can run on little energy and also exploring how to add a lightweight rechargeable battery to the system.

"It's possible the system could be used intermittently," Scherson said. "An insect equipped with a sensor could measure the amount of noxious gas in a room, broadcast the finding, shut down and recharge for an hour, then take a new measurement and broadcast again."

Source: GIZMAG - via ZeitNews.org

 

Add one more data point to the decades-old debate over marijuana legalization: A new study concludes that casual pot smoking - up to one joint per day - does not affect the functioning of your lungs.

The study, published in the Jan. 11, 2012 edition of Journal of the American Medical Association, also offered up a nugget that likely will surprise many: Evidence points to slight increases in lung airflow rates and increases in lung volume from occasional marijuana use.

Air flow is the amount of air someone can blow out of their lungs one second after taking the deepest breath possible. The volume measure is the total amount of air blown out once someone has taken the deepest breath possible.

Association Between Marijuana Exposure and Pulmonary Function Over 20 Years

The study of 5115 men and women took place over two decades between March 26, 1985 and August 19, 2006 in 4 American cities: Birmingham, Chicago, Oakland, Calif., and Minneapolis.

"With marijuana use increasing and large numbers of people who have been and continue to be exposed, knowing whether it causes lasting damage to lung function is important for public-health messaging and medical use of marijuana," according to one of the study's co-authors, Stefan Kertesz. "At levels of marijuana exposure commonly seen in Americans, occasional marijuana use was associated with increases in lung air flow rates and increases in lung capacity."

He added that those increases, though not large, nonetheless were statistically significant. "And the data showed that even up to moderately high-use levels -- one joint a day for seven years -- there is no evidence of decreased air-flow rates or lung volumes," he said.

The study by researchers at the University of California, San Francisco, and the University of Alabama at Birmingham was released Tuesday by the Journal of the American Medical Association.

Echo of past findings

The findings echo results in some smaller studies that showed while marijuana contains some of the same toxic chemicals as tobacco, it does not carry the same risks for lung disease. It's not clear why that is so, but it's possible that the main active ingredient in marijuana, a chemical known as THC, makes the difference. THC causes the "high" that users feel. It also helps fight inflammation and may counteract the effects of more irritating chemicals in the drug, said Dr. Donald Tashkin, a marijuana researcher and an emeritus professor of medicine at the University of California, Los Angeles. Tashkin was not involved in the new study.

Study co-author Dr. Stefan Kertesz said there are other aspects of marijuana that may help explain the results.

Unlike cigarette smokers, marijuana users tend to breathe in deeply when they inhale a joint, which some researchers think might strengthen lung tissue. But the common lung function tests used in the study require the same kind of deep breathing that marijuana smokers are used to, so their good test results might partly reflect lots of practice, said Kertesz, a drug abuse researcher and preventive medicine specialist at the Alabama university.

Roughly equal numbers of blacks and whites took part, but no other minorities. Participants were periodically asked about recent marijuana or cigarette use and had several lung function tests during the study.

Overall, about 37 percent reported at least occasional marijuana use, and most users also reported having smoked cigarettes; 17 percent of participants said they'd smoked cigarettes but not marijuana. Those results are similar to national estimates.

On average, cigarette users smoked about 9 cigarettes daily, while average marijuana use was only a joint or two a few times a month -- typical for U.S. marijuana users, Kertesz said.

The authors calculated the effects of tobacco and marijuana separately, both in people who used only one or the other, and in people who used both. They also considered other factors that could influence lung function, including air pollution in cities studied.

The analyses showed pot didn't appear to harm lung function, but cigarettes did. Cigarette smokers' test scores worsened steadily during the study. Smoking marijuana as often as one joint daily for seven years, or one joint weekly for 20 years was not linked with worse scores. Very few study participants smoked more often than that.

Like cigarette smokers, marijuana users can develop throat irritation and coughs, but the study didn't focus on those. It also didn't examine lung cancer, but other studies haven't found any definitive link between marijuana use and cancer.

Source: © 2012 CBS Interactive Inc. All Rights Reserved.

 
By Admin (from 18/05/2012 @ 08:08:19, in en - Global Observatory, read 1180 times)

Although you may never have seen it happen yourself, it isn't all that uncommon for large objects - including people - to fall onto the tracks at subway or railway platforms. While security personnel viewing CCTV feeds will catch some of these accidents, the cameras' shots are sometimes obscured by people, poor lighting, or even the trains themselves. The results can range from lengthy delays in rail service, to fatalities. Now, however, researchers working on a project for the Université Lille Nord de France have developed a system that uses radar to automatically detect and identify objects that fall onto the tracks. When installed at a platform, the system could then shut off power to the tracks, and notify oncoming trains.

The system continuously sends out wideband radio waves, and analyzes their reflections when they're bounced back by a foreign object, via an Automatic Target Recognition procedure. Only the most prominent features of the object's reflected signal are processed, and then compared to a database of known objects.

In a computer simulation, the researchers tested the system using objects such as suitcases, bottles, and the bodies of human adults, adolescents and children. In all cases, it was able to accurately identify the objects. Physical tests were also conducted in an echo-free chamber, in which the radio waves were guided towards two men, a woman, and two pieces of luggage made of different materials. Once again, it was able to differentiate between the subjects.

"We hope these devices will be used in the near future since they are very complementary to existing video systems and have a similar final cost," said Ali Mroué, lead author of a paper on the research. "The complementary use of video and radar systems could lead to low levels of false detection, which is mandatory for this application, and maximize the chance of survival for passengers who have fallen on the line."

Source: GizMag - via zeitnews.org

 
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