Johns Hopkins researchers have trained the immune systems of mice to fight melanoma, a deadly skin cancer, by using nanoparticles designed to target cancer-fighting immune cells, The experiments, described in ACS Nano February 24, represent a significant step toward using nanoparticles and magnetism to treat a variety of conditions, the researchers say.
“By using small enough particles, we could, for the first time, see a key difference in cancer-fighting cells, and we harnessed that knowledge to enhance the immune attack on cancer,” said Jonathan Schneck, M.D., Ph.D., a professor of pathology, medicine and oncology at the Johns Hopkins University School of Medicine‘s Institute for Cell Engineering.
Schneck’s team has pioneered the development of artificial white blood cells...
(Phys.org) —When the sun sets on a remote desert outpost and solar panels shut down, what energy source will provide power through the night? A battery, perhaps, or an old diesel generator? Perhaps something strange and new.
Physicists at the Harvard School of Engineering and Applied Sciences (SEAS) envision a device that would harvest energy from Earth's infrared emissions into outer space.
Heated by the sun, our planet is warm compared to the frigid vacuum beyond. Thanks to recent technological advances, the researchers say, that heat imbalance could soon be transformed into direct-current (DC) power, taking advantage of a vast and untapped energy source.
Their analysis of the thermodynamics, practical concerns, and technological requirements will be published this week in the Proceedings of the National Academy of Sciences.
"It's not at all obvious, at first, how you would generate DC power by emitting infrared light in free space toward the cold," says principal investigator Federico Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering at Harvard SEAS. "To generate power by emitting, not by absorbing light, that's weird. It makes sense physically once you think about it, but it's highly counterintuitive. We're talking about the use of physics at the nanoscale for a completely new application."
International Business TimesIn Time For Christmas, Science Toys For Girls Aim To Close Gender GapInternational Business TimesBut when the average person thinks of "girl's toys," the odds are good that science-themed toys such as building blocks,...
That the Universe is largely composed of a cosmic web consisting of narrow filaments upon which galaxies and intergalactic gas and dust are concentrated has been known for more than a decade. While a great deal of evidence for this has accumulated, visual evidence has been difficult to find. Astronomers have now photographed what appears to be a segment of a cosmic filament stimulated into fluorescence by irradiation from a nearby quasar.
The filaments of the cosmic web are difficult to see visually. They consist primarily of dark matter and intergalactic gas and dust, none of which have a visible signature detectable across billions of light years. As a result, our knowledge of filaments primarily comes from gravitational lensing studies, radio observations, and x-ray telescopes.
Now a team, led by researchers at the University of California, Santa Cruz (UCSC), has found an unusual configuration of celestial objects that appears to make visible a part of a filament that is ten billion light years distant. The section of the filament that is visible takes the form of a huge asymmetric nebula of diffuse intergalactic gas.
Normally this gas would not emit significant amounts of light, but in this case the intergalactic gas is being irradiated by extreme UV light from a nearby quasar; the active center of a galaxy. This irradiation ionized the gas (mostly consisting of atomic hydrogen), which then emits the characteristic light of atomic hydrogen (Lyman-alpha radiation) when the ionized atoms regain their electrons. When redshift (z~2.27) is taken into account, the Lyman-alpha radiation appears to our instruments as a violet glow.
The map above is also a product of the SDSS, which used a 2.5 meter telescope to image and determine redshift (and thereby distance) for galaxies in the cosmic vicinity of the Milky Way galaxy. It includes galaxies and quasars located in a thin slice of the sky above the Earth's equator out to a distance of two billion light years. One's first impression is of a slice through a foam of luminous bodies that lay on the boundary of huge voids.
Rather solid evidence also exists for the existence of filaments with a goodly share of dark matter, as illustrated in the above figure of just such a dark matter filament. This filament stretches about sixty million light years between the galaxy clusters Abell 222 and 223. X-ray emissions from the filament suggest that nearly 10 percent of the filament's mass consists of hot gas. This filament comprises at least dark matter and intergalactic gas.
The team published a report in the January 19, 2014, issue of Nature of their discovery of a rather unusual configuration of celestial objects in the early history of the Universe (about three billion years after the Big Bang) that provides additional evidence for the existence of the cosmic web.
The time and distances discussed in this article amaze me, "billions of light years", that's light traveling at 186,000 miles a second for billions of years, the distances involved in space travel should be enough to convince anyone that our best hope for the future by far is to look after this amazing planet !
My boys love to talk about the biggest bone in their body (the femur) and the largest muscle (the gluteus maximus). What is it with boys and big? I stumped them recently when I asked them to name the body’s largest organ. They debated between the large intestine and the liver. Nope, neither.
Our skin is our largest organ. It protects us from harsh temperatures, sunlight and chemicals, and also prevents infections from entering our bodies. It makes Vitamin D and has sensors that tell our brains what is happening in the world outside our bodies. Our skin also excretes toxins and waste products — pounds of them a day. And for the aged, it can often tell a story right on our faces!
you may take your skin for granted, well until you age and your skin becomes thin and fragile, prevention is far better than cure, how bio accumulative are vitamin tablets is still debatable, correct diet is still the best way to go !
Stunning new data not yet publicly released shows Louisiana losing its battle with rising seas much more quickly than even the most pessimistic studies have predicted to date.
While state officials continue to argue over restoration projects to save the state’s sinking, crumbling coast, top researchers at the National Oceanic and Atmospheric Administration have concluded that Louisiana is in line for the highest rate of sea-level rise “on the planet.”
The news of NOAA’s new calculations comes on the heels a 2011 U.S. Geological Survey report, which found that coastal Louisiana had lost 1,883 square miles of land between 1932 and 2010 — an area almost the size of the state of Delaware. (See the map at the top of this post.) From 1985 to 2010, the report found a rate of wetland loss amounting to 16.57 square miles every year. That works out to the loss of an area the size of one football field every hour.
Nearly half of that wetland loss occurred in the Terrebonne and Barataria wetland basins. These are home to Terrebonne Parish, source of inspiration to Beasts director Zeitlin, and neighboring Lafourche parish. (The latter was in the news in early January, with reports of cemeteries washing away.)
Evidence from Siberian caves suggests that a global temperature rise of 1.5 degrees Celsius could see permanently frozen ground thaw over a large area of Siberia, threatening release of carbon from soils, and damage to natural and human environments.
A thaw in Siberia's permafrost (ground frozen throughout the year) could eventually release over 1,000 giga-tonnes of the greenhouse gases carbon dioxide and methane into the atmosphere, potentially enhancing global warming.
The data comes from an international team led by Oxford University scientists studying stalactites and stalagmites from caves located along the 'permafrost frontier', where ground begins to be permanently frozen in a layer tens to hundreds of metres thick. Because stalactites and stalagmites only grow when liquid rainwater and snow melt drips into the caves, these formations record 500,000 years of changing permafrost conditions, including warmer periods similar to the climate of today.
Records from a particularly warm period (Marine Isotopic Stage 11) that occurred around 400,000 years ago suggest that global warming of 1.5 degrees Celsius compared to the modern (pre-industrial) climate is enough to cause substantial thawing of permafrost far north from its present-day southern limit.
'The stalactites and stalagmites from these caves are a way of looking back in time to see how warm periods similar to our modern climate affect how far permafrost extends across Siberia,' said Dr Anton Vaks of Oxford University's Department of Earth Sciences, who led the work. 'As permafrost covers 24% of the land surface of the Northern hemisphere significant thawing could affect vast areas and release giga-tonnes of carbon.
'This has huge implications for ecosystems in the region, and for aspects of the human environment. For instance, natural gas facilities in the region, as well as power lines, roads, railways and buildings are all built on permafrost and are vulnerable to thawing. Such a thaw could damage this infrastructure with obvious economic implications.'
There is huge potential in solar power. The sun is a giant ball of burning hydrogen in the sky, and it’s going to be sticking around for at least a few more billion years. For all intents and purposes, it’s a free source of energy. Sadly, humanity hasn’t been very good at harnessing its power directly. Our current methods of capturing the sun’s energy are very inefficient. For example, modern silicon and indium-tin-oxide-based solar cells are approaching the theoretical limit of 33.7% efficiency. Well, a research team at Princeton has used nanotechnology to create a mesh that increases efficiency over organic solar cells nearly three fold.
Led by Stephen Chou, the team has made two dramatic improvements: reducing reflectivity, and more effectively capturing the light that isn’t reflected. As you can see by the illustration below by Dimitri Karetnikov, Princeton’s new solar cell is much thinner and less reflective. By utilizing sandwiched plastic and metal with the nanomesh, this so-called “Plasmonic Cavity with Subwavelength Hole array” or “PlaCSH” substantially reduces the potential for losing the light itself. In fact, it only reflects about 4% of direct sunlight, leading to a 52% higher efficiency than conventional, organic solar cells.
PlaCSH is also capable of capturing a large amount of sunlight even when the sunlight is dispersed on cloudy days, which results in an amazing 81% increase in efficiency under indirect lighting conditions when compared to conventional organic solar cell technology. All told, PlaCSH is up to 175% more efficient than conventional solar cells. As you can see in the image to the right, the difference in reflectivity between conventional and PlaCSH solar cells is really quite dramatic.
The gold mesh that sits on top is incredibly small. It’s only 30 nanometers thick. The holes in the mesh are a mere 175nm in diameter. This replaces the much thicker traditional top layer made out of indium-tin-oxide (ITO). This is the most important part of the innovation. Because the mesh is actually smaller than the wavelength of the light it’s trying to collect, it exploits the bizarre way that light works in subwavelength structures. This unique physical property allows the researchers to effectively capture the light once it enters the holes in the mesh instead of letting much of it reflect away. The bottom layer of the cell remains the same, but this implementation allows the semiconducting layer of plastic in the middle of the cell to be much thinner.
The research team believes that the cells can be made cost effectively using a nanofabrication method that Chou himself invented over a decade ago. Most importantly, it replaces the costly ITO element from solar cells. This will be affordable, and much more flexible than the brittle ITO layer of traditional solar cells. While research is still being done using semiconducting materials other than plastic, this method should work for silicon and gallium arsenide solar cells as well, so it will be able to reduce the size and cost of them drastically while providing similar efficiency benefits.
Via Dr. Stefan Gruenwald