But it’s not just weight gain that poses a risk. People who are underweight also have an elevated risk of dementia, unlike people who are normal weight or overweight.

US researchers carried out a detailed review of 10 international studies published since 1995, covering just over 37,000 people, including 2,534 with various forms of dementia. Subjects were aged between 40 and 80 years when the studies started, with follow-up periods ranging from three to 36 years.

The review, which included studies from the USA, France, Finland, Sweden and Japan, also included a sophisticated meta-analysis of seven of the studies, published between 2003 and 2007 with a follow-up period of at least five years.

All kinds of dementia were included, with specific reference to Alzheimer’s Disease and to vascular dementia — where areas of the brain stop functioning because the blood vessels that supply them are damaged by conditions such as high blood pressure or heart disease.

“Our meta-analysis showed that obesity increased the relative risk of dementia, for both sexes, by an average of 42 percent when compared with normal weight” says Dr Youfa Wang, Associate Professor of International Health and Epidemiology at Johns Hopkins Bloomberg School of Public Health, Baltimore.

“And being underweight increased the risk by 36 percent.

“But when we looked specifically at Alzheimer’s Disease, the increased risk posed by obesity was 80 percent. The increased risk for people with vascular dementia was 73 percent.

“The risks were greater in studies where sufferers developed Alzheimer’s Disease or vascular dementia before the age of 60 or in studies with follow-up periods of more than 10 years.

“We also found that obesity was more likely to be a risk factor for women when it came to developing Alzheimer’s Disease and for men when it came to vascular dementia.”

The authors estimate that 12 percent of the dementia risk in the study population could be attributed to obesity, with this rising to just over 21 percent in patients with Alzheimer’s Disease.

It’s estimated that up to 10 percent of people aged 65 or more suffer from some form of dementia and two-thirds of those have Alzheimer’s Disease.

“There has been controversy about the links between obesity and dementia for a number of years, but previous findings have been mixed and inconclusive” says Dr Wang.

“The advantage of carrying out a meta-analysis is that it provides researchers with access to a large number of study subjects and it is possible to iron out the inconsistencies and come to overarching conclusions.

“Our detailed analysis clearly shows a U-shaped relationship between weight and dementia, with people who are obese or underweight facing a greater risk.

“We believe that our results show that reducing the prevalence of obesity is a promising strategy for preventing the progression of normal ageing into Alzheimer’s Disease.”

[Annette Whibley @ Wiley-Blackwell]

A workshop on terrorist organizations and the Internet was organized for the North American Treaty Organization (NATO) by the Netvision Institute for Internet Studies (NIIS) and the Interdisciplinary Center for Technology Analysis & Forecasting, both of Tel Aviv University. Berlin’s Institute for Cooperation Management and Interdisciplinary Research (NEXUS), affiliated with the Technical University of Berlin, also participated in the workshop.

The findings were presented in Berlin to a closed audience of high-ranking representatives from NATO in February 2008.

Organizing and Recruiting Online

Enlisted by NATO officials to study the web activity of terrorist organizations, researchers found that some of the world’s most dangerous organizations are operating on American turf. Hezbollah, the Islamic Jihad, and al-Qaeda all have websites hosted by popular American Internet service providers — the same companies that most of us use every day.

“These websites hosted in America are targeting Muslim mothers in America, Canada, the U.K. and all over the world, convincing them that being ‘Shahid’ or a suicide bomber is particularly good and very important for their sons,” says Prof. Niv Ahituv of the NIIS.

Available in English, Arabic, Spanish and other languages, the websites also provide tutorials on bomb building and enlist impressionable American and British Muslim women and men into a life of terror activity.

Free-Speech for Terrorists

Prof. Ahituv acknowledges the dilemma that America’s First Amendment creates — free-speech protections may foster propaganda directed towards the U.S. “America’s First Amendment protects these websites from being shut down,” he says, recognizing the irony of waging a war on terror when some of the most dangerous propaganda is being created at home.

According to the study, the Islamic Jihad operates 15 websites in Arabic and English, hosted by both U.S. and Canadian companies. Hamas operates 20 websites in eight languages, a portion of which are based in the U.S and Canada, while Hezbollah operates 20 websites, also hosted by companies in the U.S. and Canada.

Limited Successes and American Law

The FBI has shut down a few websites, but American law prevents the closure of most, says Prof. Ahituv. Terrorists could coordinate a 9/11-scale attack via these websites, he warns. There are, however, some people who believe that leaving those websites intact is desired in order to monitor content, trends and policy. It is hard to tell which side is right, adds Prof. Ahituv.

An issue of great concern is that terrorist organizations are using the Internet to bypass the role of the established press, he notes. “Since those organizations do not possess TV stations, radio stations and printed press outlets, they use the Internet to impart their views and events to the public and to the media.”

More information about the Netvision Institute for Internet Studies here.

[George Hunka @ American Friends of Tel Aviv University]

“People concerned with the effects of gas prices were significantly less attentive on the job, less excited about going to work, less passionate and conscientious and more tense,” Hochwarter said. “These people also reported more ‘blues’ on the job. Employees were simply unable to detach themselves from the stress caused by escalating gas prices as they walked through the doors at work.”

Hochwarter gleaned the information by surveying more than 800 full-time employees this spring when gas prices hovered at about $3.50 per gallon. All of the people surveyed work in a wide range of occupations, primarily in the southeastern United States. All drove personal transportation to work and had an average commute of 15 miles each way.

Survey respondents said gas prices were foremost on their mind, including a disgruntled factory worker who wrote, “I spend more time at work trying to figure out what I need to give up to keep gas in my tank than thinking about how to do my job.”

Hochwarter’s research will be submitted for publication later this summer. Among his findings:

• 52 percent have reconsidered taking vacations or other recreational activities

• 45 percent have had to cut back on debt-reduction payments, such as credit card payments
• Nearly 30 percent considered the consequences of going without basics including food, clothing and medicine
• 45 percent report that the escalating gas prices have “caused them to fall behind financially”
• 39 percent agreed with the statement “Gas prices have decreased my standard of living”
• About 33 percent — or one in three — said they would quit their job for a comparable one nearer to home

Hochwarter’s discussions with employees confirm the study’s results. Many employees report that gas prices rank as the No. 1 water-cooler discussion topic, ahead of family, sports or work, he said. He found little difference in responses among different ages, gender, work tenure and occupations.

“Several employees said they simply could not escape the media onslaught of bad news regarding the future of gas prices, and many reported their financial futures were looking bleaker and bleaker,” Hochwarter said.

As gas prices rise, so does the stress. Consider the words of Sandy, a medical records clerk: “The more it goes up, the more behind I get. If gas goes up to $5 or $6 a gallon, I just don’t know what I’ll do.”

[Wayne Hochwarter @ Florida State University]

In a paper published today in Nature Biotechnology, researchers led by Los Alamos National Laboratory and the U.S. Department of Energy Joint Genome Institute announced that the genetic sequence of the fungus Tricoderma reesei has uncovered important clues about how the organism breaks down plant fibers into simple sugars. The finding could unlock possibilities for industrial processes that can more efficiently and cost effectively convert corn, switchgrass and even cellulose-based municipal waste into ethanol. Ethanol from waste products is a more-carbon-neutral alternative to gasoline.

The fungus T. reesei rose to dubious fame during World War II when military leaders discovered it was responsible for rapid deterioration of clothing and tents in the South Pacific. Named after Dr. Elwyn T. Reese, who, with colleagues, originally isolated the hungry fungus, T. reesei was later identified as a source of industrial enzymes and a role model for the conversion of cellulose and hemicellulose — plant fibers — into simple sugars.

The organism uses enzymes it creates to break down human-indigestible fibers of plants into the simplest form of sugar, known as a monosaccharide. The fungus then digests the sugars as food.

Researchers decoded the genetic sequence of T. reesei in an attempt to discover why the deep green fungus was so darned good at digesting plant cells. The sequence results were somewhat surprising. Contrary to what one might predict about the gene content of a fungus that can eat holes in tents, T. reesei had fewer genes dedicated to the production of cellulose-eating enzymes than its counterparts.

“We were aware of T. reesei’s reputation as producer of massive quantities of degrading enzymes, however we were surprised by how few enzyme types it produces, which suggested to us that its protein secretion system is exceptionally efficient,” said Los Alamos bioscientist Diego Martinez (also at the University of New Mexico), the study’s lead author. The researchers believe that T. reesei’s genome includes “clusters” of enzyme-producing genes, a strategy that may account for the organism’s efficiency at breaking down cellulose.

On an industrial scale, T. reesei could be employed to secrete enzymes that can be purified and added into an aqueous mixture of cellulose pulp and other materials to produce sugar. The sugar can then be fermented by yeast to produce ethanol.

“The sequencing of the Trichoderma reesei genome is a major step towards using renewable feedstocks for the production of fuels and chemicals,” said Joel Cherry, director of research activities in second-generation biofuels for Novozymes, a collaborating institution in the study. “The information contained in its genome will allow us to better understand how this organism degrades cellulose so efficiently and to understand how it produces the required enzymes so prodigiously. Using this information, it may be possible to improve both of these properties, decreasing the cost of converting cellulosic biomass to fuels and chemicals.”

[James E. Rickman @ DOE/Los Alamos National Laboratory]