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'Finally freed'

In doing so, Prof Nicolelis believes they present us with a glimpse of how technology may enhance or even transform us as "the brain is finally freed from the body and it can act upon the world directly".

This mind reading technology is now appearing in some humans.

Following a devastating car accident, 23-year-old Erik Ramsey was left paralysed form the neck down. He's unable to move, talk or eat without assistance, yet his brain remains intact.

Now Erik is at the centre of an experimental therapy to try and restore his ability to speak by connecting his brain to a computer.

When Erik thinks a sound the computer reads Erik's brain activity and turns it in to an actual sound.

To date, Erik and the computer are able to make just a few basic sounds, but the hope remains that within a matter of years he will be able to make useful, vocal communication once more.

Earlier this year US scientists implanted a sensor in a paralysed man's brain that has enabled him to control objects by using his thoughts alone.

Matthew Nagle, 25 at the time of the trial, was left paralysed from the neck down and confined to a wheelchair after a knife attack in 2001. He was the first patient to try out the brain sensor.

But rather than offer us hope, another leading computer scientist believes these inroads in to the mind threaten oblivion.

Professor Hugo de Garis is the architect of some of the world's most complex neural networks - computers that evolve their own intelligence.

Now he is deeply conflicted over the future he is helping to create.

Prof De Garis believes that in a matter of years machine intelligence will supersede our own by a factor of millions.

These so called artilects - short for artificial intellects - will be so powerful that they will appear "almost God-like".

But Prof De Garis fears that they may not be quite so benign.

"How will they feel about us - an inferior species?" he asks before drawing a doom-filled analogy.

"...They may treat us like mosquitoes; as pests," and simply wipe us out, he says.

Horizon is broadcast on BBC Two on 24 October at 2100 BST. Or watch online after that at the Horizon website.
Global ecosystems 'face collapse'

Current global consumption levels could result in a large-scale ecosystem collapse by the middle of the century, environmental group WWF has warned.

The group's biannual Living Planet Report said the natural world was being degraded "at a rate unprecedented in human history".

Terrestrial species had declined by 31% between 1970-2003, the findings showed.

It warned that if demand continued at the current rate, two planets would be needed to meet global demand by 2050.

The biodiversity loss was a result of resources being consumed faster than the planet could replace them, the authors said.



They added that if the world's population shared the UK's lifestyle, three planets would be needed to support their needs.

LIVING PLANET REPORT

The planet's resources are overused by 25%

Per capita the US uses four times the resources of South Africa

Polar bear populations have declined by 30%

The nations that were shown to have the largest "ecological footprints" were the United Arab Emirates, the United States and Finland.

Paul King, WWF director of campaigns, said the world was running up a "serious ecological debt".

"It is time to make some vital choices to enable people to enjoy a one planet lifestyle," he said.



Debtor countries are defined as consuming their own natural resources, or resources from elsewhere, more quickly than they can recover, or they may be releasing more CO2 than they can absorb themselves.

"The cities, power plants and homes we build today will either lock society into damaging over-consumption beyond our lifetimes, or begin to propel this and future generations towards sustainable one planet living."

The report, compiled by the Zoological Society of London (ZSL) and the Global Footprint Network, is based on data from two indicators:

* Living Planet Index - assesses the health of the planet's ecosystems

* Ecological Footprint - measures human demand on the natural world

The Living Planet Index tracked the population of 1,313 vertebrate species of fish, amphibians, reptiles, birds and mammals from around the world.

It found that these species had declined by about 30% since 1970, suggesting that natural ecosystems were being degraded at an unprecedented rate.

The Ecological Footprint measured the amount of biologically productive land and water to meet the demand for food, timber, shelter, and absorb the pollution from human activity.

The report concluded that the global footprint exceeded the earth's biocapacity by 25% in 2003, which meant that the Earth could no longer keep up with the demands being placed upon it.

The findings echo a study published earlier this month that said the world went into "ecological debt" on 9 October this year.

Countries are shown in proportion to the amount of natural resources they consume.

The study by UK-based think-tank New Economics Foundation (Nef) was based on the Ecological Footprint data compiled by the Global Footprint Network, which also provided the figures for this latest report from the WWF.

'Large-scale collapse'

One of the report's editors, Jonathan Loh from the Zoological Society of London, said: "[It] is a stark indication of the rapid and ongoing loss of biodiversity worldwide.

"Populations of species in terrestrial, marine and freshwater ecosystems have declined by more than 30% since 1970," he added.

"In the tropics the declines are even more dramatic, as natural resources are being intensively exploited for human use."

The report outlined five scenarios based on the data from the two indicators, ranging from "business as usual" to "transition to a sustainable society".

Under the "business as usual" scenario, the authors projected that to meet the demand for resources in 2050 would be twice as much as what the Earth could provide.

They warned: "At this level of ecological deficit, exhaustion of ecological assets and large-scale ecosystem collapse become increasingly likely."

To deliver a shift towards a "sustainable society" scenario would require "significant action now" on issues such as energy generation, transport and housing.

The latest Living Planet Report is the sixth in a series of publications which began in 1998.
MIT's pint-sized car engine promises high efficiency, low cost

Ethanol empowers the little engine that could

Nancy Stauffer, Laboratory for Energy and the Environment

MIT researchers are developing a half-sized gasoline engine that performs like its full-sized cousin but offers fuel efficiency approaching that of today's hybrid engine system--at a far lower cost. The key? Carefully controlled injection of ethanol, an increasingly common biofuel, directly into the engine's cylinders when there's a hill to be climbed or a car to be passed.

These small engines could be on the market within five years, and consumers should find them appealing: By spending about an extra $1,000 and adding a couple of gallons of ethanol every few months, they will have an engine that can go as much as 30 percent farther on a gallon of fuel than an ordinary engine. Moreover, the little engine provides high performance without the use of high-octane gasoline.

Given the short fuel-savings payback time--three to four years at present U.S. gasoline prices--the researchers believe that their "ethanol-boosted" turbo engine has real potential for widespread adoption. The impact on U.S. oil consumption could be substantial. For example, if all of today's cars had the new engine, current U.S. gasoline consumption of 140 billion gallons per year would drop by more than 30 billion gallons.

"There's a tremendous need to find low-cost, practical ways to make engines more efficient and clean and to find cost-effective ways to use more biofuels in place of oil," said Daniel R. Cohn, senior research scientist in the Laboratory for Energy and the Environment and the Plasma Science and Fusion Center (PSFC).

Cohn, John B. Heywood, the Sun Jae Professor of Mechanical Engineering and director of the Sloan Automotive Laboratory, and Leslie Bromberg, a principal researcher at the PSFC, have an engine concept that promises to achieve those goals.

For decades, efforts to improve the efficiency of the conventional spark-ignition (SI) gasoline engine have been stymied by a barrier known as the "knock limit": Changes that would have made the engine far more efficient would have caused knock--spontaneous combustion that makes a metallic clanging noise and can damage the engine. Now, using sophisticated computer simulations, the MIT team has found a way to use ethanol to suppress spontaneous combustion and essentially remove the knock limit.

When the engine is working hard and knock is likely, a small amount of ethanol is directly injected into the hot combustion chamber, where it quickly vaporizes, cooling the fuel and air and making spontaneous combustion much less likely. According to a simulation developed by Bromberg, with ethanol injection the engine won't knock even when the pressure inside the cylinder is three times higher than that in a conventional SI engine. Engine tests by collaborators at Ford Motor Company produced results consistent with the model's predictions.

With knock essentially eliminated, the researchers could incorporate into their engine two operating techniques that help make today's diesel engines so efficient, but without causing the high emissions levels of diesels. First, the engine is highly turbocharged. In other words, the incoming air is compressed so that more air and fuel can fit inside the cylinder. The result: An engine of a given size can produce more power.

Second, the engine can be designed with a higher compression ratio (the ratio of the volume of the combustion chamber after compression to the volume before). The burning gases expand more in each cycle, getting more energy out of a given amount of fuel.

The combined changes could increase the power of a given-sized engine by more than a factor of two. But rather than seeking higher vehicle performance--the trend in recent decades--the researchers shrank their engine to half the size. Using well-established computer models, they determined that their small, turbocharged, high-compression-ratio engine will provide the same peak power as the full-scale SI version but will be 20 to 30 percent more fuel efficient.

But designing an efficient engine isn't enough. "To actually affect oil consumption, we need to have people want to buy our engine," said Cohn, "so our work also emphasizes keeping down the added cost and minimizing any inconvenience to the driver."

The ethanol-boosted engine could provide efficiency gains comparable to those of today's hybrid engine system for less extra investment--about $1,000 as opposed to $3,000 to $5,000. The engine should use less than five gallons of ethanol for every 100 gallons of gasoline, so drivers would need to fill their ethanol tank only every one to three months. And the ethanol could be E85, the ethanol/gasoline mixture now being pushed by federal legislation.

Through their startup company, Ethanol Boosting Systems LLC, the researchers are working with their Ford collaborators on testing and developing this new concept. If all goes as expected, within five years vehicles with the new engine could be on the road, using an alternative fuel to replace a bit of gasoline and make more efficient use of the rest.
Extensively Drug-Resistant Tuberculosis Is an Emerging Threat, Reports International Team of Researchers

October 26, 2006 — (BRONX, NY) — Strains of tuberculosis (TB) that are resistant to both first-line and second-line drugs could threaten the success of not only tuberculosis programs, but also HIV treatment programs worldwide, according to an article published online this week in The Lancet. The report details a study by a team of investigators from the United States and South Africa, who found that highly resistant strains of TB were more common than previously thought in a rural area of KwaZulu Natal, South Africa, and were associated with high death rates in patients with HIV infection. TB accounts for approximately 1.7 million deaths worldwide, each year, and is the leading cause of death in HIV-infected patients in low-income countries.

In the study, presented by Dr. Neel Gandhi, assistant professor of medicine at the Albert Einstein College of Medicine of Yeshiva University, the researchers tested patients with suspected tuberculosis for MDR and XDR strains. They found that of 1,539 patients, 221 had MDR tuberculosis, and 53 of these had XDR tuberculosis. The prevalence rates in a group of 475 patients with confirmed tuberculosis were 39% for MDR and 6% for XDR tuberculosis—higher rates than previously reported in the area. All patients with XDR disease who were tested for HIV were co-infected with the virus, and all but one died.

(Dr. Gandhi conducted this research while he completing fellowships at Yale University School of Medicine and Emory University. He joined the Einstein faculty in August 2006.)

Further complicating the problem posed by multidrug-resistance is the fact that the epidemics of tuberculosis and HIV in South Africa are closely linked. Risk of tuberculosis disease is greatly increased in people with HIV infection, and multidrug-resistant (MDR) tuberculosis is emerging as a major cause of death in these patients. The term extensively drug-resistant (XDR) tuberculosis has recently been used to describe strains that are resistant to second-line drugs—i.e., drugs that are used if the recommended first drug treatment regimen fails.

Investigation of the patients’ histories and the genetic makeup of the infecting bacteria suggested that transmission of XDR strains had occurred recently, that transmission between individuals had occurred, and that some patients had been infected while in hospital. The researchers say that these findings are worrying, since hospitals in low-income countries have limited infection-control facilities and a high proportion of susceptible HIV-infected patients. They recommend action to tackle the problem of resistant strains that could jeopardise attempts to control tuberculosis and prevent mortality in HIV patients.

In addition to Dr. Gandhi, other researchers involved in the collaborative project were Dr. Gerald Friedland, director of the AIDS Program at Yale University; Dr. Tony Moll, of the Church of Scotland Hospital in Tugela Ferry, South Africa; and Drs. Willem Sturm, Robert Pawinksi and Umesh Lalloo, of the Nelson R. Mandela School of Medicine, in Durban, South Africa.

UWM brain research supports drug development from jellyfish protein

Testing of aequorin yields promising results

With the research support from the University of Wisconsin-Milwaukee, a Wisconsin biotech company has found that a compound from a protein found in jellyfish is neuro-protective and may be effective in treating neurodegenerative diseases.

Testing of aequorin has yielded promising results, said Mark Y. Underwood of Quincy Bioscience located in Madison. Researcher James Moyer, Jr., an assistant professor at UW-Milwaukee, subjected brain cells to the "lab" equivalent of a stroke, and more than half treated with aequorin survived without residual toxicity.

Why does it work? Diseases like Alzheimer's are associated with a loss of "calcium-binding" proteins that protect nerve cells, said Moyer. Calcium is necessary for communication between neurons in the brain, and learning and memory are not possible without it. But too much of it leads to neuron death, interfering with memory and contributing to neurodegenerative diseases.

"There are ways in which cells control the influx of calcium, such as sequestering it by binding it with certain proteins," said Moyer. "If it weren't for these proteins, the high level of calcium would overwhelm the neuron and trigger a cascade of events ultimately leading to cell death."

Calcium-binding proteins decline with age, however, limiting the brain's ability to control or handle the amount of calcium "allowed in."

Aequorin, the jellyfish protein, appears to be a viable substitute.

Moyer, like Underwood, is interested in the "calcium hypothesis of aging and dementia," which is just one of many theories that attempts to explain what is going on in neuron degeneration.

He became interested in aequorin as an undergraduate at UW-Milwaukee, after reading an article that linked the stings of jellyfish with the symptoms of multiple sclerosis, a disease of the central nervous system that his mother has.

Aequorin was discovered in the 1960s and has been used in research for a long time as an indicator of calcium. But the protein has never been tried as a treatment to control calcium levels. Underwood believes his company is at about the 12-year mark in the typical 15-year cycle for a new drug to be developed.

Moyer's research centers on brain changes that occur as a result of aging. Specifically, he is interested in the part of the brain called the hippocampus, which is responsible for forming new memories. These capabilities not only deteriorate in neurodegenerative disorders such as Alzheimer's disease, but they also become impaired simply by aging.

Aging increases the number of "doors" that allow calcium ions to enter the cells, he said.

Moyer, who came to UW-Milwaukee from a post-doctoral position at Yale University, performs Pavlovian trace conditioning experiments to evaluate aging-related learning and memory deficits. These tasks first teach rodents to associate one stimulus with another and then test their memory of the association. During training, the stimuli are separated by a brief period of time, which requires the animal to maintain a memory of the first stimulus. The "stimulus free" period makes the task more difficult, especially for older animals.

Moyer's work also has implications outside of disease. He is able to show that at middle age, when the animal's learning ability or memory is not yet impaired, it already shows a drop in the number of neurons that contain an important calcium-binding protein.

"That cellular changes precede memory deficits indicates there is a window of opportunity for intervention before it's too late," he says. "Once the cells are lost, there is little chance of regaining normal brain function."
Profiles of serial killers have limitations

Serial killer profiles

(SACRAMENTO, Calif.) – Dennis Rader, the notorious BTK murderer who eluded capture for more than 30 years until his arrest in 2005, did not fit precisely into the FBI's method for profiling serial killers on the basis of crime scenes.

And Aileen Wuornos, the Florida prostitute executed in 2002 for slaying seven men over a two-year period in the early 1990s, didn't fit at all because the database of convicted serial killers used by the FBI in developing their profiling method did not include women.

The cases of Rader and Wuornos are among the topics to be explored during a panel discussion led by Dr. Charles L. Scott, a forensic psychiatrist at UC Davis Health System, at the annual meeting of the American Academy of Psychiatry and the Law Friday at the Marriott Hotel in downtown Chicago. Scott will examine the way the bureau develops the personality profiles used by investigators in serial murder cases. He also will look at alternative profiling methods, such as one developed by a crime writer that uses motive to sketch a female offender's likely character traits.

"The FBI profiling method has many positive attributes. But it also has some inherent limitations," Scott said. Scott, associate professor of clinical psychiatry with the Department of Psychiatry and Behavioral Science, will be one of four panelists in the talk, dubbed "Serial Killers: From Cradle to Grave." It is one of many events slated at the meeting, which began Thursday and runs through Sunday. The annual conference seeks to cover the major issues facing forensic psychiatrists.

Scott has extensive experience in legal psychiatric issues. He directs the psychiatry department's forensic case seminar, which trains psychiatrists in criminal and civil psychiatric evaluations, including assessments on insanity, competency to stand trial, personal injury evaluations, medical malpractice and danger assessments. He also serves as psychiatric consultant to the Sacramento County Jail and directs his department's forensic psychiatry residency program, overseeing training and education in landmark mental health law cases.

The purpose of Friday's panel discussion is not to critique the FBI, Scott said. Instead, it is to acquaint forensic psychiatrists with how the bureau profiles serial killers, defined as someone who has killed at least three times.

"Often, forensic psychiatrists are not trained in how the FBI does its analysis," Scott said.

Such training is important, Scott said, because forensic psychiatrists can play "an important collaborative role" with law enforcement when it comes to profiling. To support his view, Scott will cite a study that found psychiatrists were more accurate than police in profiling murder suspects. To an FBI agent, the crime scene is the key.

"The FBI would say the crime scene is like a fingerprint," Scott said. Interpreted properly, "it is likely to identify the kind of offender who would do this."

According to Scott, the bureau categorizes murder crime scenes as either organized or disorganized. An organized crime scene is one in which the killer exerted careful control of the environment and left little evidence behind. This suggests a well-educated and socially competent suspect. In a disorganized crime scene, things are left in disarray and evidence is plentiful. This suggests a murderer with a low level of education and social competence who may habitually use alcohol or drugs.

The problem with that approach, Scott said, is that crime scenes often have both organized and disorganized components. Take Rader's first crime scene, when he killed Joseph and Julie Otero and their two children on Jan. 15, 1974. There was clear evidence of advance planning and the murderer's domination of the environment – Rader both strangled and suffocated his victims, forcing them to pass out and then allowing them to revive somewhat "as a way to extend their death," Scott said.

But, Scott said, there were disorganized elements as well. Rader -- or BTK for Bind, Torture, and Kill -- left behind the Venetian blind cords he used as a strangling device. He also did not get rid of the bodies. While Scott stated that he has not seen any FBI profile of the BTK killer, who was sentenced to 10 consecutive life sentences last summer, Scott said that "Rader had many of the characteristics of an organized killer." For example, Rader, a resident of a Wichita, Kan., suburb, was employed and lived near his crime scenes. As a result, Scott said the signs of disorganization that were present in his first crime scene and in subsequent ones were potential red herrings, at least in terms of developing a profile. Rader was not, for example, under the influence of alcohol during his killings, nor did he frequently travel and change jobs -- traits of an organized killer under the FBI scheme.

When the FBI develops profiles of serial killers, Scott said the bureau is relying on interviews its investigators have conducted with 36 convicted sexual or serial murderers. Scott said a shortcoming with the database is that it does not include a single female serial killer. Consequently, its applicability to someone like Wuornos, portrayed in the 2003 movie "Monster" by Charlize Theron, "just isn't there," Scott said.



The database's relevance to non-Caucasian serial killers is also lacking, Scott said, as 90 percent of the men interviewed were white. It also doesn't explain a "very rare subset -- children who serially kill," Scott said. Probably the most well-known in this category, Scott said, is Jesse Pomeroy, a Massachusetts boy who, in the 1870s, brutalized other boys when he was only 12 and who killed a 10-year-old girl when he was 14.



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