From: owner-associates-digest@lists.xmission.com (associates-digest) To: associates-digest@lists.xmission.com Subject: associates-digest V1 #9 Reply-To: associates-digest Sender: owner-associates-digest@lists.xmission.com Errors-To: owner-associates-digest@lists.xmission.com Precedence: bulk associates-digest Tuesday, August 24 1999 Volume 01 : Number 009 (associates) Nanoelectronics (associates) scientists teach chimpanzee to speak English (associates) Nanogirl News ---------------------------------------------------------------------- Date: Fri, 23 Jul 1999 21:55:26 -0700 From: "Gina Miller" Subject: (associates) Nanoelectronics http://www.oc.uiuc.edu/NB/99.07/electronicstip.html News From the University of Illinois at Urbana-Champaign July 1999 ELECTRONICS Simulation uses quantum mechanics to understand nanoelectronics CHAMPAIGN, Ill. -- A computer simulation developed at the University of Illinois is helping scientists better understand the strange world of nanoelectronics -- where a single electron can control a device, but quantum mechanics is required to describe the behavior of that electron. "We have simulated the operation of a silicon quantum-dot, floating-gate flash memory device," said Jean-Pierre Leburton, a U. of I. professor of electrical and computer engineering and a researcher at the university's Beckman Institute for Advanced Science and Technology. "The simulation can be used to explore and enhance the physical characteristics in future commercial devices." Small, fast and rugged, flash memories can serve as temporary data storage in portable computers and cellular phones, and are key elements in digital imaging. They will eventually replace conventional magnetic storage media, Leburton said. "As fabrication technology continues to improve, the floating gates in flash memories may be reduced to nanometer-size structures that behave like quantum dots." But as devices shrink to nanometer proportions, classical theory breaks down and quantum mechanics takes over. "You come to a point where things have become so small, you can identify the effects of a single electron charge with its wave-like behavior," Leburton said. This "single-electron effect" reflects the granularity of matter in the nanoelectronic world. Not only must electrical current be understood as discrete particles governed by quantum mechanics (instead of millions of electrons flowing like a fluid); the physical composition of the device itself also must be taken into consideration. "For example, the conductivity of a semiconductor is changed during manufacture by doping the material with impurities," Leburton said. "In the past, this doped material could be treated as a uniformly distributed background. Now, because of the incredibly small size, the characteristics of the device will change depending upon where atomic impurities are located." To more thoroughly study the behavior of nanoelectronic devices, Leburton and graduate student Aaron Thean developed special simulation software. Their code consists of a three-dimensional, self-consistent solver with the necessary quantum mechanics to capture both the granularity of matter and the wave nature of the electron. "In our simulation, you can see the wave-particle duality of the electron," Leburton said. "On one hand you see the granularity of matter due to the presence of a single, charged particle. On the other hand you see the wave nature of the electron, manifested in the form of additional capacitances." By taking both of these effects into consideration, the computer simulation can help scientists and engineers design and optimize the performance of the next generation of nanoscale electronic devices. The researchers discuss their simulation in the June issue of IEEE Electron Device Letters. Gina "Nanogirl" Miller Get the Nanotechnology Industries Newsletter at: http://www.homestead.com/nanonews/describe.html Join the nano email thread at: http://www.onelist.com/subscribe/nanotech/ Nanotechnology Industries Web: http://www.nanoindustries.com E-mail: nanogirl@halcyon.com Alternate E-mail echoz@hotmail.com "Nanotechnology: solutions for the future." - - To unsubscribe from associates, send an email to "majordomo@xmission.com" with "unsubscribe associates" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Sun, 25 Jul 1999 18:44:22 -0600 From: Rich Thomson Subject: (associates) scientists teach chimpanzee to speak English The beginnings of uplifting? - - To unsubscribe from associates, send an email to "majordomo@xmission.com" with "unsubscribe associates" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ Date: Tue, 24 Aug 1999 18:58:29 -0700 From: "Gina Miller" Subject: (associates) Nanogirl News Nanogirl news~ *New nanocomposite material combines virtues of cellulose, paper and plastics Researchers at Virginia Tech have developed a one-step process = for creating thermoplastic nanocomposites from cellulose fibers. http://www.eurekalert.org/releases/vate-nnm081799.html *Hypothyroidism During Pregnancy Linked To Lower IQ For Child Children born to mothers with untreated hypothyroidism during pregnancy score lower on IQ tests than children of healthy mothers, according to a study conducted by Dr. James Haddow and partially funded by the National Institute of Child Health and Human Development. http://www.nichd.nih.gov/new/releases/hypothyroid.htm *TWO KANSAS RESEARCHERS WORK AT FOREFRONT OF EMERGING TECHNOLOGY: Writing= in the latest issue of Science magazine, released Aug. 20, Kansas State University chemist David Wetzel and co-author Steven LeVine of the University of Kansas Medical Center describe advances in the rapidly emerging technology, infrared microspectroscopy, and its increasing applications for biological and other research. http://www.newss.ksu.edu/WEB/News/NewsReleases/wetzel8209.html *Wired's website was cracked Original site: http://www.wired.com/news/ Cracked site: http://www.hackernews.com/archive/1999/wired/mirror.html ABC T.V.'s official site was cracked Original site: http://abc.go.com/ What the hackers left behind: http://www.hackernews.com/archive/1999/abc/mirror.html *Slashdot, the "News For Nerds. Stuff That Matters." website has been acquired by Andover.net. http://ireland.iol.ie/~kooltek/slashadover.html *SMART FABRIC REMOVES SMELL Parents of newborns rejoice! There=92s a new fabric under development th= at kills odors by itself. Researchers are experimenting with a long-lasting compound that kills pathogenic and odor-causing bacteria, not to mention = a few viruses to boot. The development was announced this week at the natio= nal meeting of the American Chemical Society. And if the smart fabric begins = to wear out of its smell-killing properties, you can recharge it by rinsing = it in bleach and water. Clothing manufacturers are eyeing it carefully, especially since the process to put it in fabric isn=92t much different t= han the permanent press finish that leaves clothes wrinkle free. This means clothing manufacturers wouldn=92t have to change anything significant on = their assembly line. You might see this special fabric as early as six months f= rom now, although the heavy-duty applications such as for use in hospitals, n= eed more time. http://cnn.com/HEALTH/9908/24/germfree.clothes/index.html *X-RAY SPACE IMAGES COMING When the first images from the world's most powerful X-ray telescope are released this week, no one will await them with greater anticipation than the scientist who's spent 22 years helping make those images possible. Dr. Martin Weisskopf of NASA has spent every day of his life for the last two decades working on the Chandra X-ray Observatory project. And he didn=92= t go in blindly =96 when he joined the project in 1977, he took out a piece of paper and wrote his estimate when the telescope would launch: the year 20= 00. The Observatory is a satellite in orbit that will, for the first time, le= t scientists see x-ray images of Earth and space. It=92s expected in the fu= ture, these new images might help us discover the structure and evolution of th= e universe. (T Moffit) *NASA launched a 60-story-high balloon to the upper fringes of Earth's atmosphere to collect precious particles of some of the rarest stuff in t= he universe, antimatter. http://www.kalmbach.com/astro/news/news/0899Antimatter.html *Federal funds should be used to speed research and development of human embryonic stem cells for a variety of potential treatments and cures, say= s a preliminary report from the nation's largest scientific group on the controversial issue. http://www.boston.com/dailyglobe2/236/nation/Panel_advocates_stem_cell_re= sea rch+.shtml *Fluorescent monkeys may shed a valuable scientific light (can you believ= e green, glowing monekys!) http://www2.nando.net/noframes/story/0,2107,84968-134265-934871-0,00.html *Genomica, organizes gene data. Software for biologists and geneticists. Genomica was founded in 1996 by Thomas G. Marr, who holds doctorates in biology and computer science, and who has been involved since 1985 in the Human Genome Project. http://insidedenver.com/business/0822corp5.shtml *The World Wide Web, widely thought of as an endless cornucopia of choice= , appears to be shrinking. It is not shrinking in the total number of Websi= tes being published - that is rising faster than ever - but in the number of Websites surfers visit and how long they spend there. http://news.bbc.co.uk/hi/english/sci/tech/newsid_428000/428999.stm *Scotland scientists search for laziness in our genes. http://news.bbc.co.uk/hi/english/uk/scotland/newsid_428000/428864.stm *A race to the edge of the solar system and into interstellar space could come out of a contract awarded recently by NASA for the University of Washington to develop an innovative space propulsion concept. The Mini-Magnetospheric Plasma Propulsion - M2P2 - would use the solar wind t= o push on a small imitation of the Earth's magnetosphere and accelerate the spacecraft to overtake the Pioneers and Voyagers and become the first manmade object to leave the solar system. http://science.nasa.gov/newhome/headlines/prop19aug99_1.htm *A little stretch of DNA can turn promiscuous, antisocial animals into friendly and faithful mates, scientists said on Wednesday. http://cnn.com/NATURE/9908/18/science.mice.reut/index.html *MSNBC's story called "Surviving the greenhouse" (carbon emissions warmin= g the planet) http://www.msnbc.com/news/291336.asp *Scientists have taken pictures that show the smelling part of the brain = in action. http://abcnews.go.com/sections/science/DailyNews/smell990823.html *(Article in New Scientist Planet) A dissident group of astronomers is claiming that the Universe is not the smooth, homogeneous place that Einstein envisaged. If they're right, says Marcus Chown, the foundations = of cosmology could crumble to dust. http://www.newscientist.co.uk/ns/19990821/fracturedu.html *Cells' damage control results in multiple mutations Scientists have long known that ultraviolet radiation in large enough dos= es is not a good thing. Among other things, it can cause genetic mutations, = the altering of cells in ways that are injurious to an organism. But research= ers have never quite understood how this process worked exactly, not even at = the level of a common, and much-studied, bacterium: Escherichia coli. Zap E. coli with a sufficient amount of UV radiation (found in the portion of th= e electromagnetic spectrum between visible violet light and X rays) and the exposed bacteria begins to produce cellular mutations at an alarming rate. The natural presumption has always been that UV rays were the culprit, bu= t new research by molecular biologists at the [ University of Southern California ] suggests the villain may lie within. While radiation is stil= l the stimulus, studies by Myron F. Goodman and colleagues indicate that mo= st of the mutations resulting in exposed E. coli are self-inflicted wounds created by a highly error- prone system of emergency DNA copying. It's no= t that E. coli doesn't know what to do when exposed to UV radiation. When placed in such situations, the bacteria's response is to launch a highly developed emergency defense mechanism that repairs damage almost immediately, often within an hour of exposure. "The cell has an extraordinary ability to repair and restore damaged DNA," said Goodman. "= So the mystery was, if these repair systems were so efficient, why did ultraviolet light do so much damage? Why did we see so many mutations?" P= art of Goodman's breakthrough was revealing that the bacteria's cellular DNA-replication mechanism became inaccurate only when a complex of unusua= l proteins called umuC and umuD were present. These proteins, generally loc= ked up tight within DNA, are released only under certain stresses, such as excessive UV radiation. Goodman described it as the bacteria's "SOS response." "What everyone assumed," said Goodman "was that these umu proteins somehow inhibited, or interfered with, the DNA copying enzymes."= In other words, they behaved like microscopic monkey wrenches. But after mon= ths of painstaking lab work, Goodman and colleagues discovered that the umu protein complex was actually a new type of DNA polymerase, an enzyme that combines various nucleotides (basically sugar compounds) to form nucleic acid, the stuff of life. The umu protein compounds were highly efficient copiers of DNA, producing new versions 100 times more effectively than other, better- known DNA polymerases. But while they boosted quantity, t= hey lacked in quality. Goodman's polymerase, dubbed "pol V," makes DNA copyin= g mistakes about 100 times more often than other polymerases. Not only does= it reproduce errors caused by ultraviolet light in existing DNA, it introduc= es mistakes of its own. "What this seems to be is a last-ditch cell defense,= " said Goodman. "Faced with a choice between possible mutation and death, t= he cell chooses possible mutation." The evolutionary consequences of such an act are obvious. Exposure to a new stress like ultraviolet light forces t= he bacteria to adapt through mutation. Some mutations may prove bad, even deadly, to individual organisms, but the species on the whole benefits by becoming better suited to a new environment. Goodman's research may seem = a bit esoteric, but it has real-world applications in better understanding = of the processes of aging and cancer. More specifically, it might help expla= in why human B-cells, part of the body's immune system, are notoriously mutation prone. Of course, it will probably be a while before such lab wo= rk is translated into new treatments or therapies. In the meantime, wear sunscreen. Gina "Nanogirl" Miller Nanotechnology Industries Web:http://www.nanoindustries.com Personal website at: http://www.homestead.com/nanotechind/nothingatall.ht= ml E-mail:nanogirl@halcyon.com Alternate E-mail nanogina@aol.com "Nanotechnology: solutions for the future." - - To unsubscribe from associates, send an email to "majordomo@xmission.com" with "unsubscribe associates" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message. ------------------------------ End of associates-digest V1 #9 ****************************** - To unsubscribe from $LIST, send an email to "majordomo@xmission.com" with "unsubscribe $LIST" in the body of the message. For information on digests or retrieving files and old messages send "help" to the same address. Do not use quotes in your message.