November 29, 2008

Yeast and Mice and Probably Humans have At Least One Common Cellular Aging Mechanism

Using a mouse genetically altered to model lymphoma, extra copies of the sirtuin gene were applied or they were fed them the sirtuin activator resveratrol, which in turn extended their mean lifespan by 24 to 46 percent.

SIRT1 Redistribution on Chromatin Promotes Genomic Stability but Alters Gene Expression during Aging

Genomic instability and alterations in gene expression are hallmarks of eukaryotic aging. The yeast histone deacetylase Sir2 silences transcription and stabilizes repetitive DNA, but during aging or in response to a DNA break, the Sir complex relocalizes to sites of genomic instability, resulting in the desilencing of genes that cause sterility, a characteristic of yeast aging. Using embryonic stem cells, we show that mammalian Sir2, SIRT1, represses repetitive DNA and a functionally diverse set of genes across the mouse genome. In response to DNA damage, SIRT1 dissociates from these loci and relocalizes to DNA breaks to promote repair, resulting in transcriptional changes that parallel those in the aging mouse brain. Increased SIRT1 expression promotes survival in a mouse model of genomic instability and suppresses age-dependent transcriptional changes. Thus, DNA damage-induced redistribution of SIRT1 and other chromatin-modifying proteins may be a conserved mechanism of aging in eukaryotes.

"It is remarkable that an aging mechanism found in yeast a decade ago, in which sirtuins redistribute with damage or aging, is also applicable to mammals," says Leonard Guarente, Novartis Professor of Biology at MIT, who is not an author on the paper. "This should lead to new approaches to protect cells against the ravages of aging by finding drugs that can stabilize this redistribution of sirtuins over time."

November 26, 2008

Tech Roundup: IBMs Predictions; Cheaper, greener cement alternativ; Cold plasma surgery

IBM predicts five innovations will have impact over the next five years:

- Energy saving solar technology will be built into asphalt, paint and windows
- You will have a crystal ball for your health, from cheap genome sequencing
- You will talk to the Web . . . and the Web will talk back, through the use of Voicesites
- You will have your own digital shopping assistants
- Forgetting will become a distant memory, video and audio recordings on far larger hard drives and memory devices

Georgia Institute of Technology has developed a new structural material based on leftovers (fly ash, bottom ash) from coal burning. Known as Cenocell, the material offers attributes that include high strength and light weight – without the use of cement, an essential ingredient of conventional concrete. Specific densities range from 0.3 to 1.6, and the material can be manufactured to withstand pressures of up to 7,000 pounds per cubic inch. Estimates suggest the material could be manufactured for an average cost of $50 per cubic yard. Cenocell, produced from either fly ash or bottom ash in a reaction with organic chemicals, requires none of the cement or aggregate – sand and rock – used in concrete. And unlike concrete, it emerges from curing ovens in final form and does not require a lengthy period to reach full strength.

So Cenocell potentially a lot cheaper and more energy efficient than cement.

A group at The George Washington University in Washington, D.C. is studying the effects of using a cold plasma atmospheric jet on tissue using fibroblast cells. “We were able to see several effects without damage to the tissue,” Michael Keidar, a member of the Mechanical and Aerospace Engineering Department. The results of the experiment can be found in Applied Physics Letters: “Living tissue under treatment of cold plasma atmospheric jet.”

One of the problems with laser surgery is that the heat produced can damage tissue, and even lead to cell death. Attempts are being made to replace laser surgery with non-thermal plasma interaction, potentially allowing for the possibility of single cell removal without affecting the surrounding cells and tissue

November 23, 2008

Tech Roundup: Robot population forecast, super lubricant

1. BAM, a "ceramic alloy", is created by combining a metal alloy of boron, aluminium and magnesium (AlMgB14) with titanium boride (TiB2). It is the hardest material after diamond and cubic boron nitride.

-BAM is much slipperier than Teflon, with a coefficient of friction of .02 compared to .05. Lubricated steel has a friction coefficient of 0.16. The material was discovered at Ames Labs.

Applying a coating to the blades that would reduce friction and increase wear resistance could have a significant effect in boosting the efficiency of pumps, which are used in all kinds of industrial and commercial applications. According to Cook, government calculations show that a modest increase in pump efficiency resulting from use of these nanocoatings could reduce U.S. industrial energy usage by 31 trillion BTUs annually by 2030, or a savings of $179 million a year.

A photograph of an AlMgB14 coating on a steel substrate. The substrate is the mottled structure on the left-hand side of the photo and the coating is the thin, darker strip running along the edge of the steel. (The blemishes on the steel are carbide inclusions) The coating has a thickness of approximately 2 to 3 microns (about 1 ten thousandths of an inch)

2. The World Robotics 2008 report is available and has statistics and projections on the number of robots.

According to World Robotics forecasts, 1.2 million industrial robots and more than 17 million service robots will populate the world by 2011.

Highlights from the report:

* In 2007, 114,365 new industrial robots were installed worldwide, a growth of 3 percent over the previous year.
* These new robots are worth some US $6 billion. If you factor in the cost of software, peripherals, and systems engineering, the total triples to $18 billion.
* Asian countries installed 59,300 new robots in 2007. That's far more than any other region in the world, but a decline over the previous year.
* Sales of industrial robots in Europe grew by 15 percent to 34,900 units, the highest number of robots ever installed in one year.

Carnival of Space Week 80

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