#Glowing diamonds make great thermometers Diamonds are known for many things: hardness, luster, and their reputation for being a irl best friend.
But the gems have important scientific uses, too. New research suggests that a certain type of artificial diamond can be used as a nanoscale temperature probe with unmatched precision over time
and space. think this work is a real advance, says materials scientist Daniel Jaque at the Autonomous University of Madrid,
who was involved not in the study. t a good paper on a hot topic. he tiny diamond probes can measure temperatures ranging from 120 K to 900 K (53°C to 627°C) s cold
as the poles of Mars and almost 200 degrees hotter than the surface of Venus. They can also detect temperature changes across distances as small as 5 m (roughly the size of a sperm cell head) and on timescales as short as 800 picoseconds(.
0000000008 seconds. Scientists discovered the properties of the probeseported in the current issue of Applied Physics Lettershen they set out to investigate a unique defect in diamonds grown using nickel precursors.
The technique incorporates some nickel atoms into the diamond crystal structure, forming what is called an 3 defect center.
Like many other diamond defects, the S3 center emits a glow when struck by a pulse of laser light.
Scientists can then use the lifetime of the resulting luminescence to calculate the temperature of the probe:
As the temperature drops, the diamond glows for longer periods of time. Luminescent temperature probes aren a totally new idea,
but what makes the S3 defect so appealing is that it combines speed and precision across a wide range of temperatures, says materials scientist Estelle Homeyer of the University of Lyon in France
and lead author of the paper. Her co-author, spectroscopist Christophe Dujardin of the University of Lyon,
adds: here are many kinds of impurities in diamond, and this particular defect was the most interesting.
It more universal. You combine all the purposes in one probe. he superior versatility of the S3 defect comes from its electronic structure,
which can be excited at two different energy levels. This produces luminescence at two separate wavelengths that have lifetimes ranging from 277 millionths of a second to about 100 billionths of a second.
This difference makes the nickel-doped diamond luminescence extremely sensitive to fluctuations in temperature. Researchers say the diamond probes could be used for a wide range of applications
but Jaque suspects theyl be most useful for observing the nanoscopic world, in particular the minute temperature fluctuations in living cells.
But this might be limited to thin layers of cells in laboratory settings, since the visible light emitted by the diamond probes faint green glowoes not penetrate whole human tissue very well. nly infrared light can penetrate into your body.
You cannot do that by using visible light, Jaque says. Still, a micron-scale look at the thermodynamics of human cells with picosecond time resolution would be a tremendous tool for scientists.
too, says co-author Gilles Ledoux of the University of Lyon, especially in measuring the friction between two materials at very small scalesn area of study currently not very well understood.
Current techniques rely on growing diamonds with a nickel precursor and hoping the defects show up. e do not know how to prepare it.
We just collect it from many diamonds, and some of them have this effect. It a long path
but a more refined approach might allow researchers to standardize the size of diamond particles
#In surprise, Dutch court orders government to do more to fight climate change In a ruling that came as a surprise to many legal experts,
a court in The netherlands today ordered the Dutch government to dramatically intensify its fight against climate change.
The district court in The hague ruled that by 2020, The netherlands must cut CO2 EMISSIONS by 25%from 1990 levels.
The case framed global warming as a human rights violation that the Dutch government must do more to prevent.
and whether it might hurt the Dutch economy. The court acknowledged that it is has no scientific expertise in climate changeut it didn need really to
The Dutch government did not dispute the international scientific consensus on climate change. The verdict (in Dutch) relies heavily on quotes, tables,
and graphics from reports by the Intergovernmental panel on climate change and other international bodies. The court adopted the growing consensus that drastic reductions in CO2 EMISSIONS are necessary to prevent a temperature rise of more than 2°Ctarting with a reduction between 25%and 40%by 2020.
The government had argued that The netherlands cannot make such major cuts on its own, a line of reasoning that the court did not accept.
That The netherlands is responsible for less than 0. 5%of global greenhouse gas emissions isn a valid argument either
a lawyer, argued that the legal community should become much more active in the fight against climate change,
A team of bioengineers and geneticists has designed a device that can suspend a single living cell between magnets and measure its density based on how high it floats.
a cancer biologist at the University of Texas Southwestern Medical center in Dallas. Researchers have used magnets before to levitate whole creatures,
explains Utkan Demirci, a bioengineer at Stanford university in Palo alto, California. But he and his colleagues were looking for new ways to manipulate
But that would be toxic to living cells. To get around that problem, Demirci group fiddled not with the magnetic properties of the cells themselves,
a rare-earth metal that is highly magnetic and sometimes given to patients to increase contrast in an MRI.
The magnetic field is shaped to pull the gadolinium downward so metal particles push the cells upward,
which could allow clinicians to spot rare circulating tumor cells in a patient sample. The device could also distinguish red blood cells from white blood cells,
and a sign that a patient is prone to infection. Traditional methods for sorting cells rely on fluorescent molecular tags,
says Will Grover, a bioengineer at the University of California, Riverside, who was involved not in the new work.
For one, it could be much simpler than designing unique labels. ensity comes for free, Grover says. ou don have to do anything to the cells. he technique could also lead to more reliable diagnostic tests.
Cancer cells are so diverse that certain ones might not bear the antibody to which a molecular label is supposed to attach.
The dance of levitating cells can also carry information about how well a drug works.
Researchers could identify which individual cellsrom a tumor or a strain of bacteriaurvive a drug treatment and study them further, something that's not possible with current culture-and-stain tests,
who has developed a different technique for weighing single living cells by sticking them onto a tiny resonator
Theye also developing a version that attaches to cellphone cameras as a quick and portable diagnostic test. s
#'Old-age protein'may cause memory loss The next time you forget where you left your car keys,
says neurologist Dena Dubal of the University of California, San francisco (UCSF), who was involved not in the study. he importance of this work cannot be underestimated as the world population is aging rapidly. ultiple groups of scientists have shown that adding the blood of older mice to younger animalsbodies makes them sluggish, weaker,
and more forgetful. Likewise, young blood can restore the memory and energy of older mice.
Neuroscientist Saul Villeda of UCSF homed in on one actor he thought might be responsible for some of that effect:
ß2 microglobulin (B2m), an immune protein normally involved in distinguishing one own cells from invading pathogens.
B2m has also been found at increased levels in patients with Alzheimer disease and other cognitive disorders.
older animals with no B2m were better at learning and memory tasks, nearly as good as young animals at completing the water maze, for instance, the scientists report online today in Nature Medicine.
They got similar results when they engineered mice to lack another immune molecule, suggesting that B2m is part of a pathway that affects the brain. hat this shows is that you can manipulate the blood, rather than the brain, to potentially treat memory problems,
and more tractable in terms of thinking of human patients. he study is a solid confirmation of previous papers that showed B2m's important role in aging
and memory, says biologist Irina Conboy of the University of California, Berkeley, who recently published a scientific paper showing that targeting a separate molecule can lower levels of B2m
who claim to have found conclusive evidence for the existence of so-called pentaquarks within the debris of high-energy proton collisions.
one of the four main detectors at the Large hadron collider (LHC), which was behind the find.
They measured the combined energy of two of the decay products proton and a meson known as J/Psi,
and antiquarknd then totted up how many times they recorded each energy value across the thousands of collisions they studied.
They found that the number of pairings with a certain energy little under five times the mass of the protonas far higher than would be expected by chance.
Energy and mass are equivalent, according to Einstein's equation E=mc2. The researchers concluded that that was the mass of a fleeting"charmonium"pentaquark containing two up quarks, one down quark, one charm quark,
LHCB collected the data back in 2011 and 2012, but Wilkinson's team held back from announcing their discovery to avoid the fate of those who had made the earlier claims of pentaquark sightings.
the LHCB collaboration made use of data showing not only the energy of the particles produced in the CERN collisions but also their directions.
Running these data through a computer model, they found that they could get the experimental results
The research has been uploaded to the arxiv server and submitted to the journal Physical Review Letters.
"says Ken Hicks of Ohio University. Curtis Meyer of Carnegie mellon University in Pittsburgh, Pennsylvania, agrees."
"In reading the paper, I have seen nothing that I can easily point to as a potential problem,
Now, the fresh data that will flow into LHCB should enable scientists to study the pentaquarks'structure,
The new data might also lead to the discovery of other pentaquarks with different masses."
Now, a team of physicists and biologists have gone a key step further, coaxing a cell to envelop a tiny plastic sphere that acts like a resonant cavityhown in green in the micrograph abovehus placing a whole laser within a cell.
The spheres are seasoned with a fluorescent dye, so that a zap with one color of light makes them radiate at another color.
say, within cancerous tumors u
#Eye drops could dissolve cataracts Cataracts cloud the eyes of tens of millions of people around the world and nearly 17.2%of Americans over the age of 40.
Currently, the only treatment is surgeryasers or scalpels cut away the molecular grout that builds in the eye as cataracts develop,
and surgeons sometimes replace the lens. But now, a team of scientists and ophthalmologists has tested a solution in dogs that may be able to dissolve the cataract right out of the eye lens.
And the solution is itself a solution: a steroid-based eye drop. Though scientists don fully understand how cataracts form,
they do know that the ogoften seen by patients is a glob of broken proteins,
stuck together in a malfunctioning clump. When healthy, these proteins, called crystallins, help the eye lens keep its structure and transparency.
causing the signature teamy glassvision that accompanies cataracts. Coming up with a solution other than surgery has been tough.
Scientists have been hunting for years for mutations in crystallin proteins that might offer new insights
and pave the way to an alternate therapy Now, it looks like a team led by University of California (UC), San diego,
molecular biologist Ling Zhao may have done just that. Her team came up with the eye drop idea after finding that children with a genetically inherited form of cataracts shared a mutation that stopped the production of lanosterol, an important steroid in the body.
When their parents did not have the same mutation, the adults produced lanosterol and had no cataracts.
So the researchers wondered: What if lanosterol helped prevent or reduce cataracts? The team tested a lanosterol-laden solution in three separate experiments.
First, they used human lens cells to test how effectively lanosterol shrank lab models of cataracts.
They saw a significant decrease. Then, they progressed to rabbits suffering from cataracts. At the end of the 6-day experiment, 11 of 13 rabbits had gone from having severe or significant cataracts to mild cataracts or no cataracts at all.
Finally, the team moved on to dogs, using a group of seven, including black Labs, Queensland Heelers,
and Miniature pinschers with naturally occurring cataracts. The dogs responded just as the researchers hoped to the lanosterol solution,
which was given in the form of both eye injections and eye drops. The dogslenses showed the same type of dissolving pattern as the human and rabbit lens cells.
The improvement was remarkableesearchers could tell just by looking at the dogseyes that the cataracts had decreased.
But the exact mechanism of how lanosterol manages to disperse the mass of proteins remains unknown. his is a really comprehensive and compelling paperhe strongest
Ie seen of its kind in a decade, says Jonathan King, a molecular biologist at Massachusetts institute of technology in Cambridge not affiliated with the study.
He has been investigating cataract proteins since 2000. hey discovered the phenomena and then followed with all of the experiments that you should dohat as biologically relevant as you can get. uben Abagyan,
co-author of the paper and molecular biologist at UC San diego, is looking forward to seeing what the lanosterol drops can dissolve next. think the natural next step is looking to translate it into humans,
he says. here nothing more exciting than that. oe
#Cool new material could make fuel cells cheaper It not enough for a new alternative energy technology to work.
It also has to be cheap enough to compete with traditional fossil fuels. That been a high hurdle for devices called solid oxide fuel cells (SOFCS) that convert fuelsuch as methane and hydrogenirectly to electricity without burning them.
But now researchers report that theye come up with a new recipe for making key components in one type of SOFC more cheaply,
which could sharply lower its overall cost. his is an excellent technological demonstration, says Sossina Haile,
a materials scientist and fuel cell expert at Northwestern University in Evanston, Illinois, who was involved not in the work. think it going to generate a lot of excitement. fuel cell works much like a battery.
Within it, two electrodes are separated by a charge-conducting electrolyte. In the case of SOFCS, the electrolyte consists of a solid ceramic membrane.
In the typical setup, air is fed to the negatively charged electrode, or cathode, where oxygen molecules pick up extra electrons.
These oxygen ions then travel through the membrane to the positively charged anode. There, they react with molecules in the fuel
generating water, carbon dioxide, and electricity. The electricity is fed through a circuit where it powers our devices,
and then is returned to the anode. As long fuel as is fed in, the SOFC continues pumping out electricity.
SOFCS have some promising capabilities. The devices make electricity at an efficiency that can match a large natural gas-based power plant.
But whereas a power plant is huge and costs hundreds of millions of dollars to build,
SOFCS can be made to be any size. That makes them attractive as backup power sources for hospitals and manufacturing plants
as well as for producing distributed power systems not connected to the grid. But SOFCS also have their drawbacks.
In conventional, oxygen-conducting SOFCS, the membrane is made from a ceramic called yttria-stabilized zirconia,
or YSZ, and the cells operate most efficiently at 800°C to 1000°C. That means they must be made using heat-resistant materials,
which makes them too expensive for most applications. In recent years, researchers have begun exploring alternative membranes made from ceramics called yttrium-doped barium zirconates (BZY.
These devices work best at converting hydrogen gas and oxygen to water and electricity, and even work at lower temperatures around 600°C. Unlike conventional SOFCS the BZY membranes allow the flow not of negatively charged oxygen ions toward the anode,
but positively charged hydrogen ions, the opposite way, toward the cathode. But theye never matched the power output of the oxygen conducting SOFCS.
Now, Ryan Oayre, a materials scientist at the Colorado School Of mines in Golden, and his colleagues have found a way to boost the power from BZY fuel cells.
The researchers suspected one problem with the BZY membranes was in the way they were made.
Mixing the different ceramic components typically requires heating them to temperatures as high as 1700°C But at that extreme temperature,
barium vaporizes into a gas, which makes it harder to mix it uniformly throughout the ceramic.
Oayre and his colleagues have helped recently pioneer an alternative mixing scheme called solid state reactive sintering,
which lowers the blending temperature. And now they've found that adding trace amounts of
what Oayre calls agic pixie dust? actually copper oxide and nickel oxideo their ceramic mixture enables them to reduce the temperature to 1450°C,
below the threshold where barium vaporizes. That, in turn, led to more uniform BZY mixtures and improved performance of their devices.
the sweet spot temperature targeted by the fuel cell industry. Oayre and Haile caution that the new advance won revolutionize the SOFC industry overnight.
Commercial devices, by contrast, work by wiring many such devices together into what known as a fuel cell tackthat generates more power.
If future BZY-based SOFC stacks work as well as the individual devices, then it could finally produce the tipping point the fuel cell industry has been looking for n
says immunologist Richard Koup, deputy director of the Vaccine Research center at the National Institute of Allergy and Infectious diseases (NIAID) in Bethesda, Maryland,
says immunologist Jake Estes of the Frederick National Laboratory of the National Cancer Institute (a sister of NIAID) in Frederick,
Traditional methods for mapping HIV genetic material use long strings of these nucleotides, called oligomers, to find and bind to complementary strands of DNA or RNA in sample tissues.
allowing researchers to create an image of precisely where the viral genetic material is dispersed throughout the tissue sample.
Their markers light up if an additional oligomer that bridges the two halves binds to both,
but it also converts to a DNA form that allows it to weave its genes into a human chromosome.
Estes, who works with virologist Jeffrey Lifson, has developed also a DNASCOPE to visualize this HIV DNAALLED the provirushich becomes integrated into human cells
or antiretroviral (ARV) drugs. eservoirsof infected cells that hold latent provirus are a key reason why powerful combinations of ARVS cannot eliminate infections and cure people.
To double check their work, they counted HIV virions by eye in one of their new images,
HIV/AIDS researchers working to cure the infection face several obstacles that these new scopes could help overcome.
One is the lack of detectable virus in the blood plasma of patients on effective ARV therapy
whether an intervention aimed at curing the infection is working. Several techniques exist to measure changes in reservoirs,
Next Mars rovers get a speed boost IT'S time for Martian rovers to put the pedal to the metal.
With the software loaded onto a rover engineers can simply input desired waypoints for the rover to reach
The system also uses the cameras and satellite images to monitor progress. In 2012 Seeker was tested for the first time in the Atacama desert in Chile a landscape similar to that of Mars. There it guided the Robovolc rover built to traverse the edge of volcanoes over several kilometres in a single day.
Next Mars rovers get a speed boost IT'S time for Martian rovers to put the pedal to the metal.
With the software loaded onto a rover engineers can simply input desired waypoints for the rover to reach
The system also uses the cameras and satellite images to monitor progress. In 2012 Seeker was tested for the first time in the Atacama desert in Chile a landscape similar to that of Mars. There it guided the Robovolc rover built to traverse the edge of volcanoes over several kilometres in a single day.
and broadcast a ham radio signal for amateurs to tune in to o
#Spacecraft seek geysers without human help When the Rosetta spacecraft sends its lander to the surface of a comet on 12 november the lander will follow prearranged orders from Earth to touch down safely
and send data home for analysis . But future spacecraft may be able to do it all on their own.
Kiri Wagstaff and her colleagues at the Jet propulsion laboratory in Pasadena California have developed software that can identify a plume of water
The researchers tested the software on unprocessed images of comet Hartley 2 and Saturn's moon Enceladus.
But the software will be of even more benefit on future missions to the outer solar system and eventually planetary systems outside our solar system.
and muscle density change with time during a mission says Gordon Sarty at the University of Saskatchewan in Canada.
and after data we have today. Hospital MRI machines can weigh more than a tonne thanks to their strong superconducting magnets making them impractical for the ISS.
So Sarty and his colleagues at MRI manufacturer MRI-Tech Canada of Calgary Alberta and space flight hardware maker Com Dev International of Cambridge Ontario have developed a technique called Transmit Array Spatial Encoding
Conventional MRIS found in hospitals work by inducing a magnetic field gradient across your entire body.
Additional radio signals cause the protons in your body's liquids to resonate with the magnetic field
This helps medical technicians localise and examine tissues inside your body but requires bulky equipment.
To shrink down TRASE uses a novel radio wave timing technique that requires much smaller magnets.
Instead of creating a magnetic field across the entire body the device sends superfast radio pulses into a small area of the body like a wrist.
All this significantly reduces the hardware complexity of an MRI which saves us considerable weight making it suitable for space flight Sarty told New Scientist.
You'll see new applications in the ER in surgery with telehealth in remote communities and even in ambulances.
While a system based on permanent magnets sounds perfect for use in space where power is scarce the Canadians will have their work cut out expanding the technology On earth predicts David Taylor founder of scanner-maker MR Solutions in Guildford UK.
But in 1974 Stephen Hawking of the University of Cambridge predicted they should emit a faint glow of particles now known as Hawking radiation.
In 2010 a team led by Francesco Belgiorno at the University of Milan made a model black hole the horizon
This tells us that the idea of Hawking actually works Steinhauer says. A black hole should really produce Hawking radiation.
The Hawking effect comes from quantum noise at the horizon says William Unruh at the University of British columbia in Canada one of the first to propose fluid-based black hole analogues.
In the future he hopes to improve his detectors to sense radiation from a single horizon which could help determine
This work is really impressive says Daniele Faccio at Heriot-Watt University in Edinburgh in the UK who was on the team that made the fibre-optic based black hole.
Although he stands by his work as the first to show that Hawking-like effects can be measured he admits that it was more open to interpretation than Steinhauer's. This work has raised really the bar
I think this work is really a game changer. Unruh is reserved a bit more. I would not say that the case is provenbut it is probably the closest anyone has come he says.
The mathematics and the results are too similar to just be a coincidence. Journal reference:
The hypersensitive methane detector on NASA's Mars rover curiosity is being repurposed to ferret out gas leaks On earth.
The Pacific gas and electric company in San francisco and global energy giant Chevron are testing a handheld earthbound version that is 1000 times as sensitive as existing methane sniffers.
Cliff Johnson president of the Pipeline Research Council International says the detector will help find leaks in pipelines before they get large.
Want to find out who is dumping waste near your house? You need to call the space detectives.
The pair intend to use their combined experience of space-based photographic databases and Earth observation privacy law to ensure that people can wield authentic imagery that stands up in court.
They want everyone to have the chance to use space imagery to settle legal disputes from homeowners disputing garden boundaries to businesses fighting vehicle theft.
Insurers might find it useful in investigating fraud and councils in tackling environmental assaults such as waste incineration or illegal logging and quarrying.
And it won't cost much more than having your house surveyed Harris says. It might seem a simple matter for someone to use Google earth say
or Microsoft's Bing images to obtain evidence to support their case. Why would they need space detectives?
But it is not so simple. Finding the right pictures means trawling through huge databases of historical satellite data
and lawsuits involving such approaches frequently fail. Trials have been collapsing because courts cannot be convinced of the authenticity of image data says Purdy.
For instance people cannot be given sure a satellite was working on the day in question or that the area of land imaged is actually the land at issue.
The space detectives will use their expertise in commissioning space images to order and their familiarity with the databases of space image suppliers like Digital Globe of Longmont Colorado.
Because it is always possible to modify a digital image you need strong archiving procedures plus information on
Purdy for instance advised on a case in which illegal waste incineration had ruined a large chunk of pristine land.
That led to a harsher sentence he says. In cases where images with greater resolution are needed the pair plan to use aerial imagery from drones provided local aviation and privacy laws permit.
Such cases might include a suspicious spouse checking licence plates to see if a car belongs to their partner
or an insurer checking a car is parked off-road as claimed. But most of the work will involve images taken by orbiting satellites especially as recent earth observation start-ups like Planet Labs
and Skybox Imaging make inexpensive space imagery more widely available. Paul Champion a private investigator based in Cardiff UK
and a governor of the Association of British Investigators says the notion of space-based detection is fascinating.
& Bird in London because finding the right pictures takes a lot of work. If you are looking for imagery in the past it is difficult to find exactly what you are looking for she says.
Wheeler has sought satellite imagery as evidence in three cases a murder assessing the progress of a bridge build
Her team had similar problems on the bridge case but Wheeler says someone with more specialised knowledge might have done better.
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