cheaper and more powerful and durable than lithium-ion batteries common in mobile phones and laptops and increasingly used in hybrid and electric cars.
The batteries can have three times the energy density of lithium-ion batteries, but have been sluggish. To counter that problem,
They polymerized molecules of the organic compound aniline into long chains in a phytic acid solution, then freeze-dried the three-dimensional hydrogel into an aerogel."
be it a small molecule, bacterial cell or virus, "he says. The research, in its formative stage, addresses a key problem facing current paper-based biosensing techniques which are labour-intensive, sometimes costly and inconvenient,
"researchers can now use conventional office ink jet-printers printers to print human-made DNA molecules with very high molecular weight on paper, much like printing a letter in an office.
#Researchers deliver large particles into cells at high speed The researchers created a highly efficient automated tool that delivers nanoparticles, enzymes, antibodies, bacteria and other"large-sized"cargo into mammalian cells at the rate
the only way to deliver so-called large cargo, particles up to 1 micrometer in size, into cells is by using micropipettes, syringe-like tools common in laboratories,
or chemical methods--are only useful for small molecules, which are typically several nanometers in length.
Underneath the holes is a well of liquid that includes the particles to be delivered. Researchers use a laser pulse to heat the titanium coating,
The fissure allows the particle-filled liquid underneath the cells to be jammed into them before the membrane reseals.
the researchers have proposed that electromagnetic waves are generated not only from the acceleration of electrons, but also from a phenomenon known as symmetry breaking.
the discovery could help identify the points where theories of classical electromagnetism and quantum mechanics overlap.
The phenomenon of radiation due to electron acceleration, first identified more than a century ago, has no counterpart in quantum mechanics,
where electrons are assumed to jump from higher to lower energy states. These new observations of radiation resulting from broken symmetry of the electric field may provide some link between the two fields.
The purpose of any antenna, whether in a communications tower or a mobile phone, is to launch energy into free space in the form of electromagnetic or radio waves,
"Another challenge with aerials is that certain physical variables associated with radiation of energy are understood not well.
which state that electromagnetic radiation is generated by accelerating electrons. However, this theory becomes problematic when dealing with radio wave emission from a dielectric solid, a material
which normally acts as an insulator, meaning that electrons are not free to move around. Despite this
The researchers determined that the reason for this phenomenon is due to symmetry breaking of the electric field associated with the electron acceleration.
Symmetry breaking can also apply in cases such as a pair of parallel wires in which electrons can be accelerated by applying an oscillating electric field."
The electromagnetic radiation emitted from dielectric materials is due to accelerating electrons on the metallic electrodes attached to them
you have to break the symmetry as well as have accelerating electrons--this is the missing piece of the puzzle of electromagnetic theory,
"I'm not suggesting we've come up with some grand unified theory, but these results will aid understanding of how electromagnetism
and quantum mechanics cross over and join up. It opens up a whole set of possibilities to explore."
#Breakthrough finds molecules that block previously'undruggable'protein tied to cancer The findings, which could lead to a new class of cancer drugs,
"These are reported the first small-molecule Hur inhibitors that competitively disrupt Hur-RNA binding and release the RNA,
We aimed to find a small-molecule compound that makes the hand release the rope by competing with ARE of the RNA."
The exterior surface of the membrane is dotted with receptor molecules--switches which growth factors can flip on from the outside to transmit growth cues into the cell's interior.
Every once in a while, however, a pro-growth-hormone molecule docks at a receptor on the surface, setting off a cascade of biochemical events inside the cell."
In the cell membrane, fatty molecules are decorated with the equivalent of traffic signals, and"in the default mode, the light is red."
and measured the amount of lactate (a beneficial molecule produced by bifidobacteria) in the infant's feces.
The Synthetic Muscle could be used in robotics in deep space travel such as travel to Mars because of its radiation resistance."
"Humans can only withstand a certain amount of radiation so that limits the time that people can be in space,
whereas robots particularly if they're radiation-resistant can be up there for long periods of time without being replaced."
when the material was exposed to over 300,000 RADS of gamma radiation. That is 20 times the amount that would be lethal to a human
or durability of the material due to the radiation although there was a slight change in color. Tests on selected samples of the material found it was affected not by extreme temperatures down to-271 degrees Celsius,
In its cellular membrane, the bacterium had a previously unknown type of ion transporter. The protein,
these proteins allow charged particles to flow into the cell or transport them outside the cell.
Integrating these ion transporters into the neuronal membrane makes it possible to alter their state of charge using light impulses
and each of these proteins was only permeable to certain ions. KR2 transports positively charged sodium ions out of the cell,
which is a feature that so far had been missing in the toolkit of optogenetics. However, until now neither the exact atomic structure nor the ion transport mechanism had been known--which is an important prerequisite for utilizing KR2
and adapting it for specific applications. This challenge awakened the interest of a team of structural biologists headed by Prof.
and the five-part complex that the KR2 molecule spontaneously forms under physiological conditions.""The structure of KR2 has many unique features,
A feature of KR2, that the scientists were interested particularly in was the unusual structure of the inward facing ion-uptake cavity,
"We hypothesized that this structure could act as a kind of filter causing the selectivity of KR2 for sodium ions,
"In neurons, transporting potassium ions from the cell is the natural mechanism of deactivation. Normally, an activated neuron will release them through passive potassium channels in the membrane.
"The device uses gold nanoparticles (microscopic particles) and glowing quantum dots. The researchers developed a novel approach for rapid and sensitive detection of surface proteins of viruses from blood samples of turkeys.
was first in the world to demonstrate single-atom spin qubits in silicon, reported in Nature in 2012 and 2013.
like the spin of a single phosphorus atom in isotopically enriched silicon, can be controlled using electric fields,
Associate professor Morello said the method works by distorting the shape of the electron cloud attached to the atom,
which the electron responds.""Therefore, we can selectively choose which qubit to operate. It's a bit like selecting which radio station we tune to,
Here, the'knob'is applied the voltage to a small electrode placed above the atom.""The findings suggest that it would be possible to locally control individual qubits with electric fields in a large-scale quantum computer using only inexpensive voltage generators, rather than the expensive high-frequency microwave sources.
containing only the silicon-28 isotope.""This isotope is perfectly nonmagnetic and, unlike those in naturally occurring silicon,
does not disturb the quantum bit, "Associate professor Morello said. The purified silicon was provided through collaboration with Professor Kohei Itoh from Keio University in Japan n
two molecules that have only a maintenance role in fruit flies are indispensible for initiating the blueprint in mammalian development."
a sample of blood or tissue is labeled with microbeads that bind to known cancer-related molecules
the presence of specific molecules is detected by analyzing the diffraction patterns generated by the microbeads.
and radiation used to treat cancer. The replacement of these cells through bone marrow transplantation is the only widely established therapy involving stem cells in human patients.
After the U s. dropped atomic bombs on Hiroshima and Nagasaki, doctors noticed that radiation patients weren't able to generate new white blood cells to fend off infections.
As Klaas-Jan Tielrooij comments,"the experiment uniquely combined the ultrafast pulse shaping expertise obtained from single molecule ultrafast photonics with the expertise in graphene electronics.
This interaction leads to a rapid creation of an electron distribution with an elevated electron temperature.
and rapidly converted into electron heat. Next, the electron heat is converted into a voltage at the interface of two graphene regions with different doping.
This photo-thermoelectric effect turns out to occur almost instantaneously, thus enabling the ultrafast conversion of absorbed light into electrical signals.
#Shape-shifting molecule tricks viruses into mutating themselves to death A newly developed spectroscopy method is helping to clarify the poorly understood molecular process by
Scientists design lethally mutagenic molecules such as KP1212 to resemble natural DNA bases, the adenine-thymine, cytosine-guanine base pairs."
A leading proposal suggested that KP1212 derived its mutagenicity by shape shifting--converting into a different molecular structure by repositioning its hydrogen atoms on nitrogen and oxygen atoms.
In addition to taking on different forms as a neutral molecule, KP1212 also could accept an extra proton,
The finding that the molecule could become protonated both surprised and delighted Essigmann. The work taught his team how to create even more potent shape shifters--by decorating the KP1212 scaffold with groups of atoms and molecules that further raises their ability to capture protons."
"KP1212 is about 20 percent of the way toward being an ideal therapeutic mutagen. The hints given us by the spectroscopy guide us toward even better mutagenic molecules,
"Essigmann said. Although Essigmann and Tokmakoff have known each other for years, they pursued seemingly far-removed research specialties until now.
"In our system, nanowires harvest solar energy and deliver electrons to bacteria, where carbon dioxide is reduced and combined with water for the synthesis of a variety of targeted, value-added chemical products."
"When sunlight is absorbed, photo-excited electron? hole pairs are generated in the silicon and titanium oxide nanowires,
The photo-generated electrons in the silicon will be passed onto bacteria for the CO2 reduction while the photo-generated holes in the titanium oxide split water molecules to make oxygen."
"Once the forest of nanowire arrays is established, it is populated with microbial populations that produce enzymes known to selectively catalyze the reduction of carbon dioxide.
For this study, the Berkeley team used Sporomusa ovata, an anaerobic bacterium that readily accepts electrons directly from the surrounding environment
The yields of target chemical molecules produced from the acetate were also encouraging--as high as 26-percent for butanol, a fuel comparable to gasoline, 25-percent for amorphadiene, a precursor to the antimaleria drug artemisinin,
it has attached negative ions to its surface. It thus attracts small positively charged molecules whether these are ions or drugs.
When an electrical current is applied to it, the flow of electrons generated projects the molecules of interest toward the target area.
To enable validation of this new technique, the researchers reproduced the hyperexcitability of epileptic neurons in mouse brains in vitro.
They then injected GABA, a compound naturally produced in the brain and that inhibits neurons,
which the researchers named lymphocyte expansion molecule, or LEM. They went on to show that LEM modulates the proliferation of human T cells as well as in mice.
Light-controlled molecule switching Dr. Artur Erbe, physicist at the HZDR, is convinced that in the future molecular electronics will open the door for novel and increasingly smaller--while also more energy efficient--components or sensors:"
"Single molecules are currently the smallest imaginable components capable of being integrated into a processor.""Scientists have succeed yet to in tailoring a molecule
so that it can conduct an electrical current and that this current can be selectively turned on and off like an electrical switch.
This requires a molecule in which an otherwise strong bond between individual atoms dissolves in one location
--and forms again precisely when energy is pumped into the structure. Dr. Jannic Wolf, chemist at the University of Konstanz, discovered through complex experiments that a particular diarylethene compound is an eligible candidate.
The advantages of this molecule, approximately three nanometres in size, are that it rotates very little
a behaviour that the scientists from Konstanz and Dresden were able to demonstrate with certainty in numerous reproducible measurements for the first time in a single molecule.
where the molecules are contacted within the solution. In order to ascertain what effects the solution conditions have on the switching process,
"We developed a nanotechnology at the HZDR that relies on extremely thin tips made of very few gold atoms.
When a beam of light then hits the molecule, it switches from its open to its closed state, resulting in a flowing current."
"For the first time ever we could switch on a single contacted molecule and prove that this precise molecule becomes a conductor on
which we have used the light beam, "says Dr. Erbe, pleased with the results.""We have characterized also the molecular switching mechanism in extremely high detail,
"Our colleagues from the HZDR theory group are computing how precisely the molecule must rotate
Together with the chemists from Konstanz, we will be able to accordingly implement the design and synthesis for the molecule."
The diarylethene molecule contact using electron-beam lithography and the subsequent measurements alone lasted three long years.
but what couldn't be proven at the time with certainty was that the change in conductivity was bound to a single molecule.
"DNA molecules are, for instance, able to arrange themselves into structures without any outside assistance. If we succeed in constructing logical switches from self-organizing molecules,
then computers of the future will come from test-tubes,"Dr. Erbe prophesizes. The enormous advantages of this new technology are obvious:
#Efficient method of producing metallic nanoparticles VTT's aerosol technology reactor for nanoparticle production can generate a variety of pure metal particles, particles of various alloys and carbon-coated particles.
The process generates an extremely high particle concentration, enabling a high production speed but with low gas consumption.
by adding particles which increase radar wave attenuation. VTT's researchers believe that the reactor has many applications
#Better battery imaging paves way for renewable energy future"Iron fluoride has the potential to triple the amount of energy a conventional lithium-ion battery can store,
Jin and Li's new X-ray imaging method pinpoints each individual reaction to understand why capacity decay may be occurring."
The experiments were performed with the help of Yu-chen Karen Chen-Wiegart, Feng Wang, Jun Wang and their co-workers at Beamline X8c
The laser blast only lasted a few tens of nanoseconds, leaving the paper completely intact. In testing its conductive performance,
researchers discovered the therapeutic compounds for enhancing myelination from oligodendrocyte progenitor cells through screening a library of bioactive small molecules.
#From metal to insulator and back again Metals are compounds that are capable of conducting the flow of electrons that make up an electric current.
Metals are compounds that are capable of conducting the flow of electrons that make up an electric current.
This idea goes back to the birth of quantum mechanics in the early decades of the last century.
The onsets of these transitions can be determined by the positions of electrons within the basic structure of the material.
Insulators typically become metallic by a reduction in the spacing between atoms in the material.
electrons localize between the atoms and do not freely flow as they do in the metallic form."
and detecting terahertz radiation has limited its use. To solve these challenges consider metamaterials; materials that allow control of the properties of light-matter interactions at the fundamental level.
Detailed analysis of the directionality and polarization of the emitted radiation reveals the fundamental nature of this efficient wavelength conversion.
#Ultra-sensitive sensor detects individual electrons In the same Cambridge laboratory in the United kingdom where The british physicist J. J. Thomson discovered the electron in 1897,
European scientists have developed just a new ultra-sensitive electrical-charge sensor capable of detecting the movement of individual electrons."
and can detect the electrical charge of a single electron in less than one microsecond,"M. Fernando Gonzlez Zalba,
'will be used in quantum computers of the future to read information stored in the charge or spin of a single electron."
as well as detecting the movement of individual electrons, the device is able to control its flow
The researchers have demonstrated the possibility of detecting the charge of an electron with their device in approximately one nanosecond,
This has been achieved by coupling a gate sensor to a silicon nanotransistor where the electrons flow individually.
fridges and other electrical equipment is made up of electrons: minuscule particles carrying an electrical charge travelling in their trillions and
whose collective movement makes these appliances work. However, this is not the case of the latest cutting-edge devices such as ultra-precise biosensors, single electron transistors, molecular circuits and quantum computers.
These represent a new technological sector which bases its electronic functionality on the charge of a single electron,
a field in which the new gate sensor can offer its advantages s
#Researchers add a new wrinkle to cell culture Using a technique that introduces tiny wrinkles into sheets of graphene,
#Generating broadband terahertz radiation from a microplasma in air Researchers have shown that a laser-generated microplasma in air can be used as a source of broadband terahertz radiation.
Researchers at the University of Rochester's Institute of Optics have shown that a laser-generated microplasma in air can be used as a source of broadband terahertz radiation.
Buccheri explains that applications for terahertz radiation, a form of electromagnetic radiation named after its frequency,
but unlike X-rays it is not a form of ionizing radiation. Imaging with terahertz can,
or baggage for drugs or explosives it is useful for the terahertz radiation to be as'broadband'as possible,"
"If you were only using a source of radiation with a range around 1 terahertz you might not be able to tell two different materials apart at low spectral resolution,
An advantage of this"one-color"approach to generating terahertz radiation is the fact that the terahertz waves propagate in a different direction to the laser beam.
#Mass and shape of single molecules revealed The work was led by Professor John Sader at the University of Melbourne's School of Mathematics and Statistics and Professor Michael Roukes of the California Institute of technology.
Prof Sader says this technique revolutionises molecule detection for biologists, or indeed anyone who wants to measure extremely small objects.
"One standard way to tell the difference between molecules is to weigh them using a technique called mass spectrometry.
The problem is that different molecules can have the same weight. Now, we can tell them apart by identifying their shape,
say, a virus or a bacteria particle.""In mass spectrometry, molecules are ionised (or electrically charged)
so that an electromagnetic field can interact with them. This interaction is measured then, which gives vital information on the molecule's mass-to-charge ratio.
But this conventional technique has difficulty telling the difference between molecules with similar mass-to-charge ratios,
meaning molecule A and molecule B might be very different, but mass-spectrometry can't see this difference."
"But when a molecule lands on a vibrating NEMS device, this extra mass reduces the many vibration frequencies of the device.
The way the frequencies change depends on the mass and shape of the molecule, so we can now tell a lot about how it looks
and how much it weighs,"Prof Sader added. It's a lot like attaching a drop of solder on the string of a guitar--it changes its vibration frequency and also its tone."
"We can analyse this measurement to get both the mass and shape of the attached particle,
This complicated method involves purifying and crystallising the molecules, then firing x-rays through the sample and interpreting the resulting patterns.
because the structure of a molecule in its natural environment can be different. California Institute of technology Professor Michael Roukes says NEMS
"This new technique adds another piece of information to aid our identification of molecules, but now at the single molecule level,
which could prove useful in biomedical applications, among other uses
#Electrical power converter allows grid to easily accept power from renewable energy Doctoral student Joseph Carr developed the system with his adviser, Juan Balda, University Professor and head of the department of electrical engineering.
"Radiation pressure physics in these systems have become measurable only when the oscillator is hit by millions of photons,
Because of the increased radiation pressure coupling, the oscillator observes the electromagnetic field with the precision of a single photon.
--Some claim that the theory holds only with very small particles. Nevertheless, the existence of an upper limit for the validity region has not been found--yet.
Zeng and his colleagues unveiled the arrangements for a molecule featuring 68 gold atoms and 32 pairs of bonded sulfur-hydrogen atoms.
Sixteen of the gold atoms form the molecule's core; the remainder bond with the sulfur
with less potential energy making for a more stable molecule. The team calculates that one of the arrangements may represent the most stable possible structure in a molecule with its composition."
"Our group has helped lead the front on nano-gold research over the past 10 years,
"We've now found new coating structures of much lower energy, meaning they are closer to the reality than (previous) analyses.
The structure of the molecule's gold core was previously detailed by the Stanford team.
-and-protect"to configure potential arrangements of the remaining gold atoms and sulfur-hydrogen pairs surrounding the core.
medium and long staple--such as the fact that a short staple consists of two sulfur atoms bonded with one gold.
By combining this information with their knowledge of how many atoms reside outside the core the team reduced the number of potential arrangements from millions to mere hundreds."
"The researchers resorted to the computational approach because of the difficulty of capturing the structure via X-ray crystallography or single-particle transmission electron microscopy, two of the most common imaging methods at the atomic scale.
"A single DNA molecule, once stretched, is about two nanometers in width, "said Aydogan Ozcan, HHMI Chancellor Professor, UCLA."For perspective,
Currently, imaging single DNA molecules requires bulky, expensive optical microscopy tools, which are confined mostly to advanced laboratory settings.
Ozcan's group's latest mobile-phone optical attachment is the first to image and size the slim strand of a single DNA molecule.
which measures the length of the DNA molecules. Assuming you have a reliable data connection,
The group discovered a few wavelengths of light that allow measuring the specific fluorescence signal from photosynthesis. The team's fluorescence measurement system can record radiation at high resolution with a frequency of 5 minutes,
Virus concentrations ranged from 13 to 2350 particles per cubic meter of air. A dose of 20 norovirus particles is usually enough to cause gastroenteritis.
According to Professor Duchaine this previously unknown mode of norovirus propagation could explain why gastroenteritis outbreaks are so hard to contain:"
#UV radiations: NONO helps to mend the damage The study appeared as advanced online publication on Oncogene, a journal in cancer research from the Nature Publishing Group.
a multifunctional protein involved in melanoma development and progression, in the cellular response to UV radiations.
Normally, cells respond to radiation-induced DNA damage by activating different checkpoints which allow to stall cell cycle
showed that silencing NONO impairs cancer cell response following exposure to UV radiations. NONO-silenced cells, compared with control cells,
our findings will likely help to shed light on the molecular mechanisms of tumorigenesis, especially in tumour types like melanoma, in which exposure to UV radiations plays such a prominent part.
The first was a nuclear medicine radioisotope technique called beta-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) scintigraphy1
Radioisotopes are injected and the radiation emitted is used to create 2d images. Beta-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) is a radioisotope
whose uptake is an indicator of fatty acid metabolism in the heart. 2. An electrocardiogram (ECG) records the electrical activity of the heart.
An abnormal Q wave on an ECG is a sign of a previous myocardial infarction. It detects scar tissue formed after the heart muscle is damaged by a heart attack. 3. C reactive-protein protein is a nonspecific test used to detect inflammation in the body.
#Chemists cook up three atom-thick electronic sheets This process of film deposition is common for traditional semiconductors like silicon
when it is just atoms thick. Three atom-thick layers of molybdenum disulfide were cooked up in the lab of Jiwoong Park, associate professor of chemistry and chemical biology and member of the Kavli Institute at Cornell for Nanoscale Science.
The films were designed and grown by postdoctoral associate Kibum Kang and graduate student Saien Xie. Their work is published online in Nature, April 30."
but with different materials, it starts with a powdery precursor, forms a gas and sprinkles single atoms onto a substrate, one layer at a time.
This effectively proved that these three-atom-thick semiconducting films can be made into multilevel electronic devices of unsurpassed thinness.
The paper is titled"High-mobility three-atom-thick semiconducting films with wafer scale homogeneity.""The work was supported by the Air force Office of Scientific research,
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