Science Articles & Inventions Online

Hopelessness may increase risk of stroke

MINNEAPOLIS (UPI) – Healthy middle-aged women with feelings of hopelessness may develop neck artery thickening, a risk factor for stroke, U.S. researchers said.

Researchers at the University of Minnesota Medical School looked at 559 women — average age 50, 62 percent white, 38 percent African-American — who were generally healthy and did not show signs of clinical cardiovascular disease.

Susan A. Everson-Rose and colleagues measured hopelessness with a questionnaire assessing expectancies regarding future and personal goals. Depressive symptoms were measured with a 20-item Center for Epidemiologic Studies Depression Scale. Thickness of neck arteries was assessed using ultrasound.

The study, published online in Stroke: Journal of the American Heart Association, found hopelessness — negative thinking and feelings of uselessness — affects arteries independent of clinical depression and before women develop clinically relevant cardiovascular disease.

The researchers found a consistent, progressive and linear association between increasing neck artery thickness and rising levels of hopelessness.

Copyright 2009 by United Press International

Sourced and published by Henry Sapiecha 8th Sept 2009

Wheelchair operates by power of thought

ZARAGOZA, Spain (UPI) — Spanish university scientists have developed a wheelchair controlled by the power of thought, promising to transform life for people with severe disabilities.

The wheelchair, developed at the University of Zaragoza, has a laser sensor and a screen that displays a real-time, three-dimensional virtual reconstruction of the wheelchair’s surroundings. To steer the chair, a user concentrates on the part of the display where he or she wants to go, and electrodes in a skullcap detect the user’s brain activity and work out the destination, the researchers said.

Sensors on the wheels keep track of the chair’s position as it moves. The laser scanner detects obstacles to avoid collisions, so the chair can be used in unfamiliar surroundings, the researchers said in a paper.

Volunteers took just 45 minutes to learn how to use a prototype chair safely and accurately, said associate professor Javier Minguez, an expert in mobile robotic navigation and brain-computer interfaces who headed the chair-development team.

The prototype can handle only two thought commands a minute and can be used for only about two hours since the wet gel used to fix the electrodes to a user’s head dries and loses its effectiveness.

An improved version that could go into commercial production is being developed, Minguez said.

The wheelchair is not the first to be controlled by brain waves, but is the first to incorporate mind-control in a system of real-time navigation, route planning and collision avoidance, computer science lecturer Palaniappan Ramaswamy of Britain’s University of Essex, told New Scientist magazine.

Copyright 2009 by United Press International

Sourced and published by Henry Sapiecha 4th May 2009

Nanoparticles boost cancer treatment

SEATTLE (UPI) — U.S. researchers say combining nanoparticles with a scorpion venom compound can cut the spread of cancerous brain tumor cells by 98 percent.

The University of Washington said the nanoparticles more than double the effectiveness of chlorotoxin, a small peptide isolated from scorpion venom.

“People talk about the treatment being more effective with nanoparticles but they don’t know how much, maybe 5 percent or 10 percent,” Miqin Zhang, professor of materials science and engineering, said Friday in a release. “This was quite a surprise to us.”

The findings are published in the journal Small.

Researchers said adding nanoparticles can improve a therapy by increasing the length of time the combination lasts in the body. Nanoparticles also boost effectiveness of treatment compounds because therapeutic molecules tend to clump around each nanoparticle, the report said.

Copyright 2009 by United Press International

Sourced and published by Henry Sapiecha 22nd April 2009