Posts Tagged ‘UC San Diego’
Physicists building bigger ‘bottles’ of antimatter
If you wondered why our military sponsors this research?
Once regarded as the stuff of science fiction, antimatter—the mirror image of the ordinary matter in our observable universe—is now the focus of laboratory studies around the world.
While physicists routinely produce antimatter with radioisotopes and particle colliders, cooling these antiparticles and containing them for any length of time is another story. Once antimatter comes into contact with ordinary matter it “annihilates”—or disappears in a flash of gamma radiation.
Clifford Surko, a professor of physics at UC San Diego who is constructing what he hopes will be the world’s largest antimatter container, said physicists have recently developed new methods to make special states of antimatter in which they can create large clouds of antiparticles, compress them and make specially tailored beams for a variety of uses…
Surko said that since “positrons”—the anti-electrons predicted by English physicist Paul Dirac some 80 years ago—disappear in a burst of gamma rays whenever they come in contact with ordinary matter, accumulating and storing these antimatter particles is no small feat. But over the past few years, he added, researchers have developed new techniques to store billions of positrons for hours or more and cool them to low temperatures in order to slow their movements so they can be studied.
Surko said physicists are now able to slow positrons from radioactive sources to low energy and accumulate and store them for days in specially designed ”bottles” that have magnetic and electric fields as walls rather than matter. They have also developed methods to cool them to temperatures as low as that of liquid helium and to compress
them to high densities.
“One can then carefully push them out of the bottle in a thin stream, a beam, much like squeezing a tube of toothpaste,” said Surko, adding that there are a variety of uses for such positrons…
Surko and his colleagues are building the world’s largest trap for low-energy positrons in his laboratory at UC San Diego, capable of storing more than a trillion antimatter particles at one time.
I have to chuckle over this research – since one of the other blogs where I’m an editor is the property of a pundit who denies the existence of antimatter.
“Denial” is a funny political quantity. The always-politically-correct Right Wing in America [for PC is their invention] has succeeded in appending the concept of skeptic to denial. It’s like putting an unrecovered alcoholic in charge of the advertising for your barroom because he can claim to have no problems with drink – that he would ever admit to. The word has no place in science; but, then, the pundits who espouse denial as emblematic of skepticism are generally too lazy to read more than a paragraph or two of a scientific study.
Non-scientists don’t realize the persistent conservatism, the need for repeated testing and verification for conclusions considered at least reasonable. I followed the discussion, tests and reviews followed by more discussion in the published papers of the Max Planck Institute for 2 years at the beginning of this millennium – on the question of climate change. It took that long for just one of the hundreds of peer institutes and research centers on Earth to come to the conclusions that grounded the IPCC Report – regardless of whatever politics follow those few pages around. The scenario was repeated inside each of those bodies and continues today.
And those who deny climate change, as some deny the existence of anti-matter and any number of revelatory advances in science will continue to base that denial on little or nothing of value. Much less scientific methods. Much less reading a report.
Prion disease spread in sheep via mother’s milk
Transmission of prion brain diseases such as bovine spongiform enecephalopathy (BSE) – also known as mad cow disease – and human variant Creutzfeldt-Jakob disease (vCJD) is generally attributed to the consumption of the brain or organ meat of infected animals but new research demonstrates lambs exposed to milk from prion-infected sheep with inflamed mammary glands can develop prion disease as well. The research…has major implications for human and livestock health.
“Prions cause devastating, ultimately fatal infections in humans,” says corresponding author Christina Sigurdson… “This study is the first demonstration of prions from an inflamed organ being secreted, and causing clinical symptoms in a natural host for prion disease…”
In the new research [.pdf], the team infected sheep with a common retrovirus that causes mastitis, and misfolded prions. They bred the sheep, in order to stimulate the females to produce milk, which they then collected and fed to lambs that had never been exposed to prions. The lambs developed prion disease after only two years, a speed which surprised the researchers, and “suggested that there was a high level of prion infectivity in milk,” says Sigurdson.
The research raises several disturbing possibilities.
A common virus in a sheep with prion disease can lead to prion contamination of the milk pool and may lead to prion infection of other animals.
The same virus in a prion-infected sheep could efficiently propagate prion infection within a flock, through transmission of prions to the lambs, via milk. This might be particularly likely on factory farms, where mastitis may be common, and could occur in goats as well as sheep.
Humans with variant Creutzfeldt-Jakob disease (vCJD) might accumulate prions in inflamed organs, and could also secrete prions.
“This work cannot be directly extrapolated to cattle,” says Sigurdson. She says that BSE prions do not accumulate to detectible levels in lymphoid organs, and thus would not be expected to accumulate with inflammation.
“Nonetheless,” she says, “it would be worth testing milk from cattle with mastitis for prions as there may be other cellular sources for prions entry into milk.”
Since I don’t drink milk, it never occurred to me that it may be a vector for a disease like this. But, of course. It’s a perfectly natural source of infection. It’s just that I live in the land of beef cattle. In fact, with access to beef that is tested and certified BSE-free.
Researcher find 600 flavors of fat in human blood
Human blood is famously fraught with fats; now researchers have a specific idea of just how numerous and diverse these lipids actually are. A national research team, led by scientists at the University of California, San Diego School of Medicine, has created the first “lipidome” of human plasma, identifying and quantifying almost 600 distinct fat species circulating in human blood.
“Everybody knows about blood lipids like cholesterol and triglycerides,” said Edward A. Dennis, PhD, distinguished professor of pharmacology, chemistry and biochemistry at UC San Diego and principal investigator of LIPID MAPS, a national consortium studying the structure and function of lipids. “For the first time, we’ve identified and measured hundreds more and ultimately we might discover thousands.
These numbers and their remarkable diversity illustrate that lipids have key, specific functions, most of which we do not yet recognize or understand. This lipidome is a first step towards being able to investigate correlations between specific fat molecules and disease and developing new treatments…”
In recent years, scientists have begun to appreciate the greater, more complex roles of lipids in human biology (among them the emergence of vitamin D). The utility of lipids in building cell membranes is well known, as is their function as repositories of stored energy. Less well-understood, however, is their role as signaling molecules…
Added Dennis: “Any condition in which inflammation is a component involves lipids. In fact, it’s hard to think of a disease, including cancer, that doesn’t involve lipids in some way.”
“I look at this lipidome as something like the human genome project,” added Oswald Quehenberger. “First you have to do the sequencing. You have to know what genes – or in this case, fats – are there. Then you can begin to look at individual species, do association studies and discover how these molecules fit into systems, processes and diseases.”
I feel chunky already.
A surfboard gets an onboard computer
Computers are everywhere these days – even on surfboards. University of California, San Diego mechanical engineering undergraduates outfitted a surfboard with a computer and accompanying sensors — one step toward a structural engineering Ph.D. student’s quest to develop the science of surfboards.
The UC San Diego mechanical engineering undergraduates installed a computer and sensors on a surfboard and recorded the speed of the water flowing beneath the board. While the students surfed, the onboard computer sent water velocity information to a laptop on shore in real time…
This is part of Benjamin Thompson’s quest to discover if surfboards have an optimal flexibility – a board stiffness that makes surfing as enjoyable as possible. Thompson is a UC San Diego structural engineering Ph.D. student studying the fluid-structure interaction between surfboards and waves…
Each of the eight sensors embedded into the bottom of the board is a “bend sensor.” The faster the water beneath the board moves, with respect to the board, the more the sensors bend, explained Trevor Owen, the other surfer on the four-person mechanical engineering team…
Even though the team has finished their class project, Ferguson plans to keep working with Thompson. “This project is going to apply some science that most likely [board] shapers understand pretty well…it’s going to settle the debates. It’s going to be black and white hard data to let them know for sure which ideas work, which concepts work, and why they work…”
Yes, it’s always easy to joke about Kalifornia Kulture. But, this project fits better into Geeks in Action.
Surfing is a worldwide sport, big business. Applying cyber-mechanical analysis, fluid dynamics, to construction makes all the sense in the world. Something major manufacturers should already have been doing.
Grubby children get a head start on health
LIFE Magazine
For parents too stretched to make sure their offspring are perfectly turned out at all times, it may just be the scientific cover they’ve been waiting for.
They will now be able to answer the disapproving tuts of their more fastidious friends by pointing to research which gives biological backing to the old adage that the more germs a child is exposed to during early childhood, the better their immune system in later life
Researchers from the School of Medicine at the University of California found that being too clean could impair the skin’s ability to heal. The San Diego-based team discovered that normal bacteria that live on the skin trigger a pathway that helps prevent inflammation when we get hurt. These bugs dampen down overactive immune responses which can cause cuts and grazes to swell, or lead to rashes, according to research published in the online edition of Nature Medicine…
The pressure group Parents Outloud, which campaigns to stop children being “mollycoddled” and “oversanitised” by health and safety regulations, welcomed the research. “Hopefully research like this will help parents realise that it’s natural and healthy for children to get outdoors and get mucky and that it doesn’t do their health any harm,” said a spokeswoman, Margaret Morrissey.
At last, I realize why I came down with Mono in my high school years. It was after we moved into a home which actually had a hot water heater and all-over bathing wasn’t limited to Saturday night and heating endless buckets of water on the stovetop.
