Tag archives: biophysics
By Hamish Johnston at the CAP Congress in Edmonton, Alberta
One promising route to understanding the causes of Alzheimer’s disease (AD) – and hopefully finding a cure – is the study of how and why proteins in the brain sometimes form neurotoxic plaques. These plaques are disc-like structures that are about 50 µm in diameter and made from polypeptides. Their presence in the grey matter of the brain is strongly associated with AD and some other neurological conditions, but why they form and why they cause dementia are both not understood.
By Margaret Harris at the AAAS meeting in San Jose
“Restoration of sight to the blind” is a brave claim, one with an almost Biblical ring to it. For Daniel Palanker, though, it is beginning to look as if it is an achievable goal. A medical physicist at the University of Stanford, Palanker has developed a prosthetic vision system that replaces damaged photoreceptors in the retina with an array of tiny photodiodes. When infrared images are projected onto this array, the photodiodes convert the light pulses into electrical signals, which are then picked up by the neurons behind the retina and transmitted to the brain. The result is an artificially induced visual response that, while not as good as normal vision, could nevertheless provide “highly functional restoration of sight” to people with conditions such as retinitis pigmentosa or age-related macular degeneration (AMD).
By Margaret Harris in San Francisco
The International Year of Light is a global celebration, but right now, it’s definitely got its heart in San Francisco. For the past five days, experts in optics, lasers and biomedical imaging have been converging on the “city by the bay” for the annual Photonics West conference, and I’ve joined them in order to learn more about the hot topics in optical science.
By Susan Curtis in Baltimore, US
At the 59th annual meeting of the Biophysical Society today, Rommie Amaro of the University of California, San Diego, highlighted the power of computational methods to speed up the discovery of new drugs to treat diseases as diverse as flu and cancer. Amaro focused on a recent project conducted while she was at the University of California, Irvine, to identify compounds that could play a vital role in future anti-cancer drugs by helping to reactive a molecule called p53 that is known to inhibit the formation of cancer cells.
By Susan Curtis in Baltimore, US
I’m in Baltimore this week for the 59th annual meeting of the Biophysical Society. The field of biophysics has grown rapidly in recent years as physics-based techniques have opened up new ways to study and understand biological processes, but with my limited knowledge of biology I was nervous that I would feel a little out of my depth.
The first talk of the “New and Notable” symposium helped to allay my fears. Michelle Wang is a physicist at Cornell University in the US who exploits optical techniques to trap and manipulate biomolecules. While established methods can only trap a single biomolecule at a time, Wang and her colleagues have pioneered the use of nanophotonic structures that can trap multiple biomolecules in a standing wave created within an optical waveguide.
“Our optical-trapping innovation reduces bench-top optics to a small device on a chip,” Wang told physicsworld.com when the team first reported their so-called nanophotonic standing-wave array trap last year. Since then, Wang and her colleagues have been working to integrate fluorescent markers with the nanophotonic trap to track the position of individual biomolecules, and have also been experimenting with optical waveguide materials other than silicon to improve performance and enable new applications.
By Hamish Johnston
You may not know it, but you could be a poet.
The European Space Agency (ESA) and the Hubble Space Telescope have just launched a contest to find the best “Ode to Hubble” as part of the celebrations for Hubble’s 25th birthday. Although described as an ode, the contest is actually looking for a short video tribute to Hubble that can include verse, song, prose as well as still and moving images. The piece can either be about the telescope or one of its many discoveries. There are two age categories, one for “generation Hubble” – those born after its launch – and one for over 25s. So look to the stars and get those creative juices flowing.
By Hamish Johnston
“The past is a foreign country: they do things differently there,” is probably the only famous sentence written by the English novelist L P Hartley. It also sums up nicely a collection of photographs of CERN in the 1960s and early 1970s showing among other things a jolly worker wearing a beret, scientists wearing white lab coats and ties, and a strange religious-like procession. There are also lots of photos of vintage kit, including one of those huge vacuum-valve-powered oscilloscopes (probably from Tektronix) that would be familiar to physicists of a certain age. My favourite photo is shown above. It was taken in 1965, when 3D data visualization was actually done in 3D! I believe that the collection was put together by CERN’s Alex Brown and you can enjoy looking at all 55 images in the collection here.
By Michael Bishop
In the 60 years since James Watson and Francis Crick brought physics and biology together to unveil the molecular structure of DNA, the boundary between the two disciplines has continued to become increasingly blurred.
In this post-genomic era, ever more principles from physics have been applied to living systems in an attempt to understand complexity at all levels.
Yet cultural differences still exist between physicists and biologists, as is made clear in a set of excellent perspectives in the journal Physical Biology, published by IOP Publishing, which also publishes Physics World.
In “Perspectives on working at the physics–biology interface”, a group of eminent scientists give their accounts of working at the interface of physics and biology, describing the opportunities that have presented themselves and outlining some of the problems that they continue to face when working across two fields with quite different traditions.
A huge cycle in Sheffield, $30,000 for falsifying global warming and another physicist goes into advertising
By Hamish Johnston
Sports fans in the UK are spoiled for choice this weekend, with the Wimbledon finals in London and the kick-off of the Tour de France in Leeds. This is only the second time that the famous bicycle race has started in the UK and to celebrate, the University of Sheffield has created a huge image of a bicycle in a field near to the route. But as well as celebrating the passing cyclists, the image honours a very different cycle that makes the race and indeed much of life on Earth possible.
By Tushna Commissariat at the APS March Meeting in Denver
The word “streamers” doesn’t normally bring bacteria to mind, but it’s all the rage with biophysicists studying the mechanics of bacterial biofilms that grow where there is fluid flowing. A biofilm is any group of microorganisms where cells stick to each other on a surface – either a living or non-living surface will do. A rather simple example of this is the slimy film that develops over our teeth each night.
Biophysicist Knut Drescher from Princeton University gave a fascinating talk at the APS March Meeting on Monday about his research into why biofilms that grow specifically in the presence of a flowing fluid – such as in channels in soil, filtration systems, as well as medical devices such as stents or urinary catheters – are rapidly clogged, causing a variety of problems and infections. Biofilms in such a case form 3D thread-like “streamers” that are responsible for the rapid clogging. It was initially thought that these streamers formed along the walls of the original film and then expanded inwards, but Drescher and colleagues found that it was actually the other way around – the fishing-line-like streamers grew from the middle and rapidly extended outwards, clogging a channel within minutes.