Exercise builds small blood vessels in brain, study says
By John Fauber, Medicine & Health / Research
Exercise is known to help prevent cognitive decline and maintain the brain as people age, and now researchers think they know one reason why.
People who engaged in long-term, regular exercise had substantially more small blood vessels in their brains and more blood flow than people who performed little exercise over the years, according to a study presented Monday.
"Exercise increases the number of blood vessels in other parts of the body," said lead researcher Feraz Rahman of Jefferson Medical College in Philadelphia. "What we didn't know is that it also affects the brain."
The researchers used magnetic resonance imaging and a new three-dimensional computer reconstruction to make models of small blood vessels and blood flow in the brains of 12 healthy adults ages 59 to 75. None was considered to be cognitively impaired.
The study was presented at the Radiological Society of North America's annual meeting and is expected to be published in the next few months. It was conducted at the University of North Carolina-Chapel Hill.
Half of the volunteers had engaged in aerobic exercise at least three hours a week over the previous 10 years. The other group exercised less than one hour a week.
The models showed that the exercisers had 43 percent more blood vessels with a diameter of 0.4 millimeters to 0.6 millimeters. While an average of about 100 blood vessels of that size was found in the non-exercisers, an average of 143 was found in the exercisers. More importantly, there are thousands of blood vessels in the brain that are smaller than 0.4 millimeters, Rahman said, so it's likely that exercise also increases the number of smaller blood vessels.
Rahman compared the exercise effect with that of the branching system of a tree. While there were similar numbers of larger blood vessels and arteries, the number of smaller vessels branching off from them was reduced.
"Other studies have shown that exercise prevents cognitive decline in the elderly," he said. "The blood vessel and flow differences may be one of the reasons. Aerobic exercise is a vital part of healthy aging."
The growth of new blood vessels, a process known as angiogenesis, is known to occur around the body, including in the brain, as a response to regular exercise, said David Harder, associate dean for research at the Medical College of Wisconsin.
The researchers "have confirmed what we've known using newer technology," he said. "They can actually see and count the blood vessels."
Exercise initiates a complex process that leads to the formation of new blood vessels in the brain, Harder said. When the muscles of the body are used, electrical impulses are sent from the spine through long nerve fibers to the brain.
These electrical signals stimulate cells in the brain known as astrocytes. The astrocytes, in turn, send out a type of fatty acid that causes blood vessels to dilate. The substance, known as EET, also promotes the growth of new blood vessels, he said.
Exercise doesn't make people smarter, he said, but older people who regularly exercise tend to be more alert. And the increased blood flow in the brain that is established as a result of exercise might help maintain cognitive function as people age, said Harder, who also serves as director of the college's Cardiovascular Research Center.
"It probably is beneficial in terms of being able to maintain a normal functioning brain," he said.
For instance, Harder said his lab has been looking at slices of brains from people who died after being diagnosed with Alzheimer's disease. Those brain slices show a lack of density of small blood vessels known as capillaries.
The study also might explain why people who exercise are less likely to have a stroke, said Arvind Ahuja, chairman of neurosurgery at Aurora St. Luke's Medical Center in Milwaukee, Wis.
"Something is happening at the basic micro level," he said. "Exercise induces a lot of changes in the body that you are not aware of."
For instance, exercise prompts the release of substances that help improve blood flow, he said.
But a key question still needs to be resolved: Does exercise not only increase the number of blood vessels and capillaries, but also help maintain cognitive function? asked Vivek Prabhakaran, assistant professor of neuroradiology at the University of Wisconsin-Madison's School of Medicine and Public Health.
Some observational studies suggest that exercise helps people retain their mental ability as they age.
But what is needed is a larger study that measures blood vessels and cognitive performance together.
___
© 2008, Milwaukee Journal Sentinel.
Visit JSOnline, the Journal Sentinel's World Wide Web site, at http://www.jsonline.com/
Distributed by McClatchy-Tribune Information Services.
- wong chee tat :)
Tuesday, December 2, 2008
800 workers retrenched after wafer fab plan collapse
800 workers retrenched after wafer fab plan collapse
By Loh Chee Kong, TODAY | Posted: 31 October 2008 1216 hrs
SINGAPORE : In what is the first large-scale retrenchment here since the economy turned sour, IM Flash Technologies (IMFT) - a joint venture between chip giants Micron and Intel - has scrapped plans to build a wafer fabrication plant, laying off 800 employees in the process.
It became known on Thursday that the staff, 500 of whom are undergoing training in Utah, United States, were informed of the decision on October 13 in a meeting at the company's Lehi facility. The remaining 300 - hired as production operators and who are mostly from India - have already left the company.
At press time, IMFT's management, which is based in the US, could not be reached for comment. According to one affected Singaporean employee, the majority of the staff are non-Singaporeans. The employee told TODAY: "Prior to the meeting, everyone was already quite down. Because of the market conditions, some of us had suspicions (that there would be a massive layoff)."
Announced in 2005, the S$4.8-billion plant, which was intended to produce cutting-edge memory chips, was due to open in Woodlands later this year. It would have been one of the largest-ever investments in Singapore’s electronics industry.
But in May, its chief executive officer Rodney Morgan said the opening had been delayed until the middle of next year. While Mr Morgan reiterated the company's commitment to the project, the writing was on the wall when Micron announced on October 10 that it was laying off 15 per cent - or 3,000 - of its staff worldwide.
It said that as a result, IMFT would discontinue the supply of NAND flash memory from Micron's Boise facility in the US.
A Ministry of Manpower (MOM) spokesperson said it was "closely monitoring the employment situation and will work closely" with its tripartite partners and other relevant government agencies to "render employment assistance to workers who may be retrenched".
She added: "Companies that are considering retrenchment, or that have decided to do so, are strongly encouraged to give prior notification to MOM. Early notification will enable MOM and the relevant agencies to help companies on any potential labour relations issues as well as provide affected workers with employment assistance."
- TODAY/fa
(An update from the previous blog)
- wong chee tat :)
By Loh Chee Kong, TODAY | Posted: 31 October 2008 1216 hrs
SINGAPORE : In what is the first large-scale retrenchment here since the economy turned sour, IM Flash Technologies (IMFT) - a joint venture between chip giants Micron and Intel - has scrapped plans to build a wafer fabrication plant, laying off 800 employees in the process.
It became known on Thursday that the staff, 500 of whom are undergoing training in Utah, United States, were informed of the decision on October 13 in a meeting at the company's Lehi facility. The remaining 300 - hired as production operators and who are mostly from India - have already left the company.
At press time, IMFT's management, which is based in the US, could not be reached for comment. According to one affected Singaporean employee, the majority of the staff are non-Singaporeans. The employee told TODAY: "Prior to the meeting, everyone was already quite down. Because of the market conditions, some of us had suspicions (that there would be a massive layoff)."
Announced in 2005, the S$4.8-billion plant, which was intended to produce cutting-edge memory chips, was due to open in Woodlands later this year. It would have been one of the largest-ever investments in Singapore’s electronics industry.
But in May, its chief executive officer Rodney Morgan said the opening had been delayed until the middle of next year. While Mr Morgan reiterated the company's commitment to the project, the writing was on the wall when Micron announced on October 10 that it was laying off 15 per cent - or 3,000 - of its staff worldwide.
It said that as a result, IMFT would discontinue the supply of NAND flash memory from Micron's Boise facility in the US.
A Ministry of Manpower (MOM) spokesperson said it was "closely monitoring the employment situation and will work closely" with its tripartite partners and other relevant government agencies to "render employment assistance to workers who may be retrenched".
She added: "Companies that are considering retrenchment, or that have decided to do so, are strongly encouraged to give prior notification to MOM. Early notification will enable MOM and the relevant agencies to help companies on any potential labour relations issues as well as provide affected workers with employment assistance."
- TODAY/fa
(An update from the previous blog)
- wong chee tat :)
Intel, Hitachi to develop solid-state drives
Intel, Hitachi to develop solid-state drives
Posted by Brooke Crothers
Posted by Brooke Crothers
Intel will target solid-state drives for server computers in a tie up with Hitachi that was announced Monday night.
Intel and Hitachi Global Storage Technologies (Hitachi GST) said they will "jointly develop and deliver" Serial Attached SCSI (SAS) and Fibre Channel (FC) solid-state drives (SSDs) for servers, workstations, and storage systems.
While Hitachi is a large supplier of hard disk drives, Intel manufactures and sells consumer and enterprise-class solid-state drives. The enterprise-class X25-E Extreme SSDs that Intel offers now are based on Serial ATA (SATA) technology. As are its consumer-class drives.
Solid-state drives are generally faster than hard-disk drives, particularly at reading data.
"The combination of a leading Enterprise drive supplier with a NAND technology and manufacturing leader will produce world-class solutions in terms of reliability, performance and system compatibility," the companies said in a statement.
The agreement is exclusive to the two companies with the first Serial Attached SCSI and Fibre Channel products expected to be available in early 2010. Both Serial Attached SCSI and Fibre Channel are interfaces typically used in servers.
The companies said the SSDs will not replace hard disk drives but complement them. "The new generation of solid-state drive technology complements existing enterprise-class hard disk drives and is intended for use in storage applications that require extremely high Input/Output Operations Per Second (IOPS) performance and power efficiency," according to the two companies.
Hitachi GST said it will continue to provide its customers with both "traditional" hard-disk drives in addition to the SSDs.
The new SSDs will be "branded and exclusively sold and supported by Hitachi GST" and use Intel NAND flash memory and SSD technology.
Hitachi said it will use its expertise in drive firmware, reliability, qualification and system integration in combination with Intel's technology and manufacturing capabilities.
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