The first was a nuclear medicine radioisotope technique called beta-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) scintigraphy1
destructive molecules that are byproducts of cellular activity and especially prevalent in areas of chronic inflammation."
"One molecule of catalase can deactivate about one million free radicals per second, and it never stops
No small molecule drug even comes close to matching it in speed or efficiency.""Traditional drugs--from cold medicine to chemotherapy--are composed of small molecules of a few dozen atoms, typically.
Biopharmaceuticals, or biologics, are produced proteins by living cells. Proteins such as catalase are tens of thousands of times larger than the small molecules that make up traditional drugs.
Batrakova's goal is to develop personalized treatments by loading proteins into exosomes that have been extracted from a patient's own white blood cells.
which breaks down this molecule.""Although arginase is present throughout the body, it is primarily found in the liver.
#Bringing high-energy particle detection in from the cold Now researchers from Oak ridge National Laboratory in Tennessee think they have a good candidate material.
the researchers demonstrated the material's potential for creating high-performance, low-cost, room-temperature semiconductor radiation detectors. In a paper published this week in the Journal of Applied Physics, from AIP Publishing,
"Thallium sulfide iodide is a promising room-temperature radiation detection material, "said Mao-Hua Du, the primary researcher from Oak ridge National Laboratory."
"Native defects, a type of structural flaw in which the regular pattern of atoms is altered naturally during crystal growth, play an important role in charge carrier trapping and recombination in semiconductors.
Defects affect the charge transport in the material and ultimately the radiation detection efficiency of a device."
"From the theoretical study, we have identified the most detrimental defects that hinder the electron transport in thallium sulfide iodide
Du's research established a theoretical foundation for the development of thallium sulfide iodide radiation detectors, opening doors for a new generation of room-temperature semiconductor radiation detectors.
The Limits of Conventional Radiation Detectorssemiconductor radiation detectors are devices that measure ionizing radiation by collecting radiation-generated charge carriers in the semiconductor between electrodes under a bias voltage.
Conventional semiconductor detectors such as germanium and silicon require low temperatures to operate which limits their applications outside of laboratories.
For example, germanium detectors must be cooled to liquid nitrogen temperature (about 77 Kelvin or-196 degrees Celsius) to produce spectroscopic data.
In recent years, scientists have been seeking new materials for room-temperature radiation detectors. A semiconductor material called cadmium zinc telluride (Cdznte) has been found to be the best candidate to date,
and the bottom of the conduction band in semiconductors) and high resistivity to suppress thermally generated charge carriers for precisely detecting radiation-generated carriers.
Moreover, the detector materials need to have excellent carrier transport efficiency to make sure radiation-generated charges effectively diffuse through the crystal
Thallium sulfide iodide is an emerging semiconductor compound that has attracted attention in recent years for room-temperature radiation detection,
which all mean that thallium sulfide iodide is more efficient for radiation absorption and can be used to create a thinner, low-cost radiation detector.
A good radiation detection material should have efficient charge transport property, Du said. Native defects, the natural structure flaws in a semiconductor,
can interact with charge carriers, causing carrier trapping and scattering, thus harming the carrier transport process.
Studying the native defects and their effects on charge transport in a material are hence essential for the performance improvement of a radiation detector.
low melting temperature and so on, suggest that thallium sulfide iodide is a good candidate for fabricating new generation room-temperature radiation detectors with improved performance and lower cost than previous detectors,
researchers can use synchrotrons--dedicated facilities where electrons run laps in football-stadium-sized storage rings to produce the desired radiation
Conversely, the CLS is a miniature version of a synchrotron that produces suitable X-rays by colliding laser light with electrons circulating in a desk-sized storage ring.
"The Large hadron collider at CERN is the world's largest colliding beam storage ring, and the CLS is the smallest,
"Our results are very exciting#we are not just talking about one molecule in one particular pathogen but rather a building block
and processes which rely on coupling biological molecules to cell surfaces. The latest findings follow more than a decade of work led by Associate professor Renato Morona looking at how bacteria cause disease.
Among the other advantages are lower radiation doses than in traditional mammography, and the ready availability of the equipment on the market,
The group developed a sensitive biosensing platform that detects E coli by the aggregation of nanoparticles on cellulose Paper gold nanoparticles are covered with surface molecules that bind to E coli bacteria.
When the camp molecules accumulate the erythrocyte becomes stiffer. camp is degraded by the enzyme phosphodiesterase,
which a quantum system is integrated into a mechanical oscillating system. For the first time, the researchers were able to show that this mechanical system can be used to coherently manipulate an electron spin embedded in the resonator--without external antennas or complex microelectronic structures.
The results of this experimental study will be published in Nature Physics. In previous publications the research team led by Georg H. Endress Professor Patrick Maletinsky described how resonators made from single-crystalline diamonds with individually embedded electrons are suited highly to addressing the spin of these electrons.
These diamond resonators were modified in multiple instances so that a carbon atom from the diamond lattice was replaced with a nitrogen atom in their crystal lattices with a missing atom directly adjacent.
In these"nitrogen-vacancy centers,"individual electrons are trapped. Their"spin"or intrinsic angular momentum is examined in this research.
When the resonator now begins to oscillate, strain develops in the diamond's crystal structure. This
in turn, influences the spin of the electrons, which can indicate two possible directions("up"or"down")when measured.
The direction of the spin can be detected with the aid of fluorescence spectroscopy. Extremely fast spin oscillation In this latest publication, the scientists have shaken the resonators in a way that allows them to induce a coherent oscillation of the coupled spin for the first time.
This means that the spin of the electrons switches from up to down and vice versa in a controlled and rapid rhythm and that the scientists can control the spin status at any time.
This spin oscillation is compared fast with the frequency of the resonator. It also protects the spin against harmful decoherence mechanisms.
It is conceivable that this diamond resonator could be applied to sensors--potentially in a highly sensitive way
--because the oscillation of the resonator can be recorded via the altered spin. These new findings also allow the spin to be rotated coherently over a very long period of close to 100 microseconds,
making the measurement more precise. Nitrogen-vacancy centers could potentially also be used to develop a quantum computer.
In this case, the quick manipulation of its quantum states demonstrated in this work would be a decisive advantage e
#Waiting for pleasure It is a discovery which has implications not only for a range of neuropsychiatric disorders such as ADHD, eating disorders and anxiety disorders,
The aim now is to identify the molecules that regulate expression of this gene upstream,
which use aluminum as the key material for the lithium-ion battery's negative electrode,
Most present lithium-ion batteries--the most widely used form of rechargeable batteries--use anodes made of graphite, a form of carbon.
"This expansion and contraction of aluminum particles generates great mechanical stress, which can cause electrical contacts to disconnect.
which would be ok if not for the repeated large volume expansion and shrinkage that cause SEI particles to shed.
As a result, previous attempts to develop an aluminum electrode for lithium-ion batteries had failed.
but yolk-shell particles feature a void between the two--equivalent to where the white of an egg would be.
The aluminum particles they used, which are about 50 nanometers in diameter, naturally have oxidized an layer of alumina (Al2o3)."
a better conductor of electrons and lithium ions when it is very thin. Aluminum powders were placed in sulfuric acid saturated with titanium oxysulfate.
if the particles stay in the acid for a few more hours, the aluminum core continuously shrinks to become a 30-nm-across"yolk,,
"which shows that small ions can get through the shell. The particles are treated then to get the final aluminum-titania (ATO) yolk-shell particles.
After being tested through 500 charging-discharging cycles, the titania shell gets a bit thicker, Li says,
while allowing lithium ions and electrons to get in and out. The result is an electrode that gives more than three times the capacity of graphite (1. 2 Ah/g) at a normal charging rate
Li says. At very fast charging rates (six minutes to full charge), the capacity is still 0. 66 Ah/g after 500 cycles.
which the stem cells were clustered, released Wnt molecules into the tissue. Stem cells that migrated out of reach of that signal quickly lost their ability to divide into new stem cells
#Ultra-fast electron camera A new scientific instrument promises to capture some of nature's speediest processes.
It uses a method known as ultrafast electron diffraction (UED) and can reveal motions of electrons
and atomic nuclei within molecules that take place in less than a tenth of a trillionth of a second--information that will benefit groundbreaking research in materials science, chemistry and biology.
The technique complements ultrafast studies with SLAC's X-ray free-electron laser. Similar to X-ray light, highly energetic electrons can take snapshots of the interior of materials as they pass through them.
Yet electrons interact differently with materials and"see"different things. Both methods combined draw a more complete picture that will help researchers better understand
and possibly control important ultrafast processes in complex systems ranging from magnetic data storage devices to chemical reactions.
The superior performance of the new UED system is due to a very stable"electron gun"originally developed for SLAC's X-ray laser Linac Coherent light Source (LCLS), a DOE Office of Science User Facility.
This electron source produces highly energetic electrons, packed into extremely short bunches. It spits out 120 of these bunches every second
generating a powerful electron beam that the researchers use to probe objects on the inside.
But how can scientists actually catch a glimpse of the interior of materials with particles like electrons?
The method works because particles have a second nature: They also behave like waves. When electron waves pass through a sample,
they scatter off the sample's atomic nuclei and electrons. The scattered waves then combine to form a so-called diffraction pattern picked up by a detector.
The whole apparatus works like a high-speed camera, capturing differences in diffraction patterns over time that scientists use to reconstruct the sample's inner structure and how it changes.
Since electron bunches in SLAC's UED instrument are extremely short, they reveal changes that occur in less than 100 quadrillionths of a second, or 100 femtoseconds,
but the repulsive forces between electrons in the electron beam limited the time resolution of previous experiments,
"says the paper's first author Stephen Weathersby, the facility manager of SLAC's Accelerator Structure Test Area (ASTA),
"Electrons behave similarly to X-rays in the way they explore speedy phenomena in nature. Electrons scatter off both electrons and atomic nuclei in materials.
X-rays, on the other hand, interact only with electrons. Therefore, electron and X-ray studies of very fast structural changes complement each other.
The SLAC-led team has begun already to combine both approaches to better understand the link between the magnetic behavior of certain materials
and their structural properties in studies that could help develop next-generation data storage devices. Electrons also provide a path to studies that are very challenging to perform with X-rays."
"Electrons interact with materials much more strongly than X-rays do, "says SLAC's Renkai Li, the paper's lead author."
"We were able to analyze samples such as very thin films whose X-ray signals would be very weak."
"Due to the almost 1, 000-fold shorter wavelength of electrons compared to X-rays, UED can see much finer structural details.
We're able to see how atoms in molecules move with UED, which is an important step toward making molecular movies of ultrafast chemical reactions."
--and will eventually reduce the size of the electron beam from its current 100 microns--the diameter of an average human hair--to below one micron.
"This will generate unforeseen possibilities for ultrafast science with electrons, similar to the great things we saw happening a few years ago at LCLS,
TMDS are molecules that can be made exceedingly thin, only several atomic layers, and have an electrical property called a band gap,
These atoms form a thin, molecular sandwich with the one metal and two chalcogenides, and depending on their fabrication method can exist in several slightly different shaped atomic arrangements.
As the chips approach single or several atom thickness, (commonly referred to as 2-dimensional),
which was several atoms thick. They directed a 1 m wide laser (a human hair is 17 to 181 m) at the 2h-Mote2
#New research may enhance display, LED lighting technology Recently, quantum dots (QDS)--nano-sized semiconductor particles that produce bright, sharp,
In addition, as an actual needle application, we demonstrated fluorescenctce particle depth injection into the brain in vivo,
The Van der waals force is the attractive sum of short-range electric dipole interactions between uncharged molecules. Thanks to strong Van der waals interactions between graphene and boron nitride, CVD graphene can be separated from the copper
Raman spectroscopy and transport measurements on the graphene/boron nitride heterostructures reveals high electron mobilities comparable with those observed in similar assemblies based on exfoliated graphene.
"Even though we're not sending a huge amount of photons, at short time scales, we're sending a lot more energy to that spot than the energy sent by the sun,
#Scientists determine how antibiotic gains cancer-killing sulfur atoms In a discovery with implications for future drug design,
"Until our study, we didn't really know how sulfur atoms are incorporated into a natural product--now we have discovered a new family of enzymes
"The study links a family of enzymes--molecules that act as biological catalysts--known as polyketide synthases (PKS) directly to a complex series of chemical reactions that ultimately add sulfur to leinamycin, a member of the polyketide family of natural products."
it is particularly exciting that this new discovery now provides the possibilities of adding sulfur atoms to compounds similar to leinamycin or other polyketide natural products."
quantum mechanics has defied our natural way of thinking, and it has forced physicists to come to grips with peculiar ideas.
and from simulating complex quantum systems to efficiently solving large systems of equations. One of the most exciting and most difficult proposed quantum technologies is the quantum computer.
But it was realized recently that quantum mechanics permits one to"superimpose quantum gates.""If engineered correctly, this means that a set of quantum gates can act in all possible orders at the same time.
which the two quantum logic gates were applied to single photons in both orders. The results of their experiment confirm that it is impossible to determine which gate acted first
From a single measurement on the photon, they probed a specific property of the two quantum gates thereby confirming that the gates were applied in both orders at once.
Scientists unveil new technique for spotting quantum dots to make high performance nanophotonic devices A quantum dot should produce one and only one photon--the smallest constituent of light--each time it is energized,
which will enable control of the photons that the quantum dot generates. However finding the quantum dots--they're just about 10 nanometers across--is no small feat.
and used it to create high-performance single photon sources. Array"This is a first step towards providing accurate location information for the manufacture of high performance quantum dot devices,
Their coordinates in hand, scientists can then tell the computer-controlled electron beam lithography tool to place any structure the application calls for in its proper relation to the quantum dots,
the researchers demonstrated grating-based single photon sources in which they were able to collect 50 per cent of the quantum dot's emitted photons, the theoretical limit for this type of structure.
They also demonstrated that more than 99 per cent of the light produced from their source came out as single photons.
Such high purity is partly due to the fact that the location technique helps the researchers to quickly survey the wafer (10,000 square micrometers at a time) to find regions where the quantum dot density is especially low-only about one per 1
#New life of old molecules: Calcium carbide Remarkably, despite the above mentioned trend of mega-molecules,
state-of-the-art research anticipates re-investigation of tiny molecules. Indeed, small molecules carry a huge and previously unrevealed potential for science and industry.
Renaissance in this area of science initiated an enlightenment of the well-known small molecules. An example of a small molecule is acetylene and derivative of acetylene--Cac2 or calcium carbide.
Friedrich Wohler first introduced the prominent calcium carbide in 1862. As a matter of fact, this breakthrough revolutionized the lighting in the 20th century Europe and US.
The manufacture of carbide reached thousands of tons by the middle of the last century.
Such an increase was caused by the fact that carbide was used mainly for the production of acetylene.
investigates the synthesis of valuable organic molecules directly from calcium carbide, without separation and storage of acetylene gas.
and secondly, thiol molecules get attached to the acetylene molecules. Both processes take place one-pot
The ants'high sensitivity to pheromones allows detection of very few molecules of hydrocarbons that stick close to the cuticle surface.
Now, researchers from the University of Bristol in the UK and Nippon Telegraph and Telephone (NTT) in Japan, have pulled off the same feat for light in the quantum world by developing an optical chip that can process photons in an infinite number
which are typically extremely demanding due to the notoriously fragile nature of quantum systems. This result shows a step change for experiments with photons
and what the future looks like for quantum technologies. Dr Anthony Laing, who led the project,
Now anybody can run their own experiments with photons, much like they operate any other piece of software on a computer.
and to design entirely new protein-in-antibody molecules s
#Engineers'sandwich'atomic layers to make new materials for energy storage The scientists whose job it is to test the limits of what nature--specifically chemistry--will allow to exist, just set up shop on some new real estate on the Periodic table.
Each new combination of atom-thick layers presents new properties and researchers suspect that one, or more, of these new materials will exhibit energy storage
the researchers selectively extract layers of aluminum atoms from a block of MAX phase by etching them out with an acid."
where the titanium atoms are in center and the molybdenum on the outside. The next Frontier Now, with the help of theoretical calculations done by researchers at the FIRST ENERGY Frontier Research center at the Oak ridge National Laboratory,
The researcher explains that"ozone is composed triatomic (molecule of three atoms) oxygen which is very reactive
The method consists in converting the natural pomegranate juice in small dust particles that can be dissolved in water.
Because SR-STORM gives full spectral and spatial information for each molecule, the technology opens the door to high-resolution imaging of multiple components and local chemical environments, such as ph variations, inside a cell.
and spectrum of each individual molecule, plotting its super-resolved spatial position in two dimensions and coloring each molecule according to its spectral position,
"This is a new type of imaging, combining single-molecule spectral measurement with super-resolution microscopy."
able to deliver spatial and spectral information for millions of single molecules in about five minutes,
compared to several minutes for a single frame of image comprising tens of molecules using conventional scanning-based techniques.
Xu built on work he did as a postdoctoral researcher at Harvard with Xiaowei Zhuang, who invented STORM, a super-resolution microscopy method based on single-molecule imaging and photoswitching.
which is useful for scientists to understand the behavior of individual molecules, as well as to enable high-quality multicolor imaging of multiple targets."
but dispersed the single-molecule image collected by one objective lens into spectrum while keeping the other image for single-molecule localization,
"Now we are simultaneously accumulating the spectrum of the single molecules and also their position,
"Next they dyed the sample with 14 different dyes in a narrow emission window and excited and photoswitched the molecules with one laser.
they found that the spectra of the individual molecules were surprisingly different and thus readily identifiable."
they were able to easily distinguish molecules of different dyes based on their spectral mean alone,
and synaptotagmin-1. Earlier X-ray studies, including experiments at SLAC's Stanford Synchrotron radiation Lightsource (SSRL) nearly two decades ago,
"The study was supported also by X-ray experiments at SSRL and at Argonne National Laboratory's Advanced Photon Source."
Scientists have shown that the passage of molecules through the nucleus of a star-shaped brain cell, called an astrocyte,
a group of proteins that regulates the passage of molecules in and out of the nucleus. Their results suggest that binding enhances the flow of certain critical molecules into the nucleus
and enables astrocytes to enter a reactive state.""This research highlights the importance of the nuclear pore complex in the brain
so called because they use plasmons--collective excitations of electrons in a conductor--rather than electrons to transfer
electrons that tunnel across the gap can excite plasmons, although inefficiently.""Yang likens the excitation of plasmons in gratings to dropping pebbles in a swimming pool with swimming lanes demarcated by floats."
The photoanode uses sunlight to oxidize water molecules, generating protons and electrons as well as oxygen gas.
The photocathode recombines the protons and electrons to form hydrogen gas. A key part of the JCAP design is the plastic membrane,
which keeps the oxygen and hydrogen gases separate. If the two gases are allowed to mix
and electrons to pass through. The new complete solar fuel generation system developed by Lewis and colleagues uses such a 62.5-nanometer-thick Tio2 layer to effectively prevent corrosion
This catalyst is among the most active known catalysts for splitting water molecules into oxygen
protons, and electrons and is a key to the high efficiency displayed by the device.
while still allowing the ions to flow seamlessly to complete the electrical circuit in the cell.
the researchers etched micrometer scale pillars into a silicon surface using photolithography and deep reactive-ion etching,
an ionization platform was developed for the ultrasensitive detection of molecules. With detection limits down to the zeptomolar range (a thousand trillionth of a mole,
or about 600 molecules in a sample), this technology can analyze the metabolic composition of individual microbial cells,
and measure trace levels of small molecules via existing scientific platforms without matrix effects that mask small quantities of molecules.
however, matrix-assisted laser desorption ionization (MALDI) mass spectrometry techniques suffer from matrix-associated background problems that prevent the detection of small molecules at individual cell levels.
This process causes the ionization of cellular molecules without the hassle of a matrix. Using NAPA mass spectrometry
and xenobiotics in a broad class of samples, making it the foundation for matrix-free laser desorption ionization.
#Skimming uranium from the sea Researchers developed a protein-based, genetically encodable system that can bind water-soluble uranium with exceedingly high affinity and selectivity.
This is the first known demonstration of a bacterial system used to mine ocean-based uranium that reduces the expense
The overall method developed could find broad applications in sequestration and bioremediation of water-soluble uranium and similar transuranic elements.
This biotechnology method could also have similar applications to other low-concentration ions in solution.
Uranium plays an important role in the search for alternative energies to fossil fuels; however, uranium resources on land are limited.
The oceans are estimated to contain 1, 000 times as much uranium as is buried in deposits on land,
but unfortunately, the uranium in the ocean is in the form of water-soluble uranyl (UO22)
+which is present at a very low concentration (13.7 nm). The uranyl is bound by carbonate and other anions,
with the added complication that seawater also contains various metal ions at high concentrations, making separating the uranium extremely complex.
After years of trying to find an efficient and affordable way to extract uranyl, researchers at the University of Chicago, Peking University,
thermally stable protein called Super Uranyl-binding Protein (SUP) binds uranyl tightly (Kd of 7. 4 femtomolar) and with high selectivity(>10,000-fold selectivity over other metal ions.
and Ministry of Science and Technology of China (2009cb918500) and the National Natural science Foundation of China (21173013,11021463) to L. L. This research used the Advanced Photon Source for protein crystallography data collection
at beamlines LS/CA-CAT (21-ID-F) and NE-CAT (24-ID-C), which was supported by the U s. Department of energy, Office of Science,
#Scientists'squeeze'light one particle at a time A team of scientists has measured successfully particles of light being squeezed,
Squeezing is a strange phenomenon of quantum physics. It creates a very specific form of light
This involves exciting a single atom with just a tiny amount of light. The theory states that the light scattered by this atom should,
similarly, be squeezed. Unfortunately, although the mathematical basis for this method--known as squeezing of resonance fluorescence--was drawn up in 1981,
the experiment to observe it was so difficult that one established quantum physics textbook despairingly concludes:""It seems hopeless to measure it."
In the journal Nature, a team of physicists report that they have demonstrated successfully the squeezing of individual light particles,
or photons, using an artificially constructed atom, known as a semiconductor quantum dot. Thanks to the enhanced optical properties of this system and the technique used to make the measurements,
because we now have artificial atoms with optical properties that are superior to natural atoms.
That meant we were able to reach the necessary conditions to observe this fundamental property of photons
and prove that this odd phenomenon of squeezing really exists at the level of a single photon.
what photons should do.""Like a lot of quantum physics, the principles behind squeezing light involve some mind-boggling concepts.
It begins with the fact that wherever there are light particles, there are also associated electromagnetic fluctuations. This is a sort of static
which scientists refer to as"noise.""Typically, the more intense light gets, the higher the noise.
These are called vacuum fluctuations. While classical physics tells us that in the absence of a light source we will be in perfect darkness,
quantum mechanics tells us that there is always some of this ambient fluctuation.""If you look at a flat surface,
"The same thing is happening with vacuum fluctuations. Once you get into the quantum world, you start to get this fine print.
It looks like there are zero photons present, but actually there is just a tiny bit more than nothing."
"Importantly, these vacuum fluctuations are always present and provide a base limit to the noise of a light field.
In the Cambridge experiment, the researchers achieved this by shining a faint laser beam on to their artificial atom, the quantum dot.
This excited the quantum dot and led to the emission of a stream of individual photons.
when the dot was excited only weakly the noise associated with the light field actually dropped, becoming less than the supposed baseline of vacuum fluctuations.
Explaining why this happens involves some highly complex quantum physics. At its core, however, is a rule known as Heisenberg's uncertainty principle.
This states that in any situation in which a particle has linked two properties, only one can be measured
In the strange world of quantum physics, however, the situation changes. Heisenberg states that only one part of a pair can ever be measured,
the noise of part of the electromagnetic field was reduced to an extremely precise and low level, below the standard baseline of vacuum fluctuations.
and hence the laws of quantum physics. Plotting the uncertainty with which fluctuations in the electromagnetic field could be measured on a graph creates a shape where the uncertainty of one part has been reduced,
Atature added that the main point of the study was simply to attempt to see this property of single photons,
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