these particles tend to rapidly aggregate in physiological conditions, rendering them too large to penetrate the mesh of airway mucus. For its design,
from the prediction of chemical properties studied in computational chemistry applications to the identification of particles for high-energy physics experiments. i
The work is centered on enhancing the arrangement of colloidsmall particles suspended within a fluid medium.
with these particles attaching to each other in ways that produce chaotic or inflexible configurations. The NYU team developed a new method to apply DNA coating to colloids
However, the method, at that point, could manipulate only one type of particle. In the JACS study, the research team shows the procedure can handle five additional types of materialsnd in different combinations.
you need to have the ability for a particle to move around and find its optimal position,
and trapping molecules in recent years has opened up an entirely new energy regime for studying chemical reactivity at temperatures below one micro-Kelvin,
Working at the Center for Nanoscale Materials (CNM) and the Advanced Photon Source (APS), two DOE Office of Science User Facilities located at Argonne,
the team got membranes of gold nanoparticles coated with organic molecules to curl into tubes when hit with an electron beam.
Equally importantly, they have discovered how and why it happens. The scientists coat gold nanoparticles of a few thousand atoms each with an oil-like organic molecule that holds the gold particles together.
When floated on water the particles form a sheet; when the water evaporates, it leaves the sheet suspended over a hole. t almost like a drumhead,
says Xiao-Min Lin, the staff scientist at the Center for Nanoscale Materials who led the project. ut it a very thin membrane made of a single layer of nanoparticles. rgonne researchers are able to fold gold nanoparticle membranes in a specific
direction using an electron beam because two sides of the membrane are different. Image credit:
he answer lay in the organic surface molecules. They are hydrophobic: when floated on water they try to avoid contact with it,
When the electron beam hits the molecules on the surface it causes them to form an additional bond with their neighbors,
or about six atoms thick, is so tiny it would not normally be measurable. Subramanian Sankaranarayanan and Sanket Deshmukh at CNM used the high-performance computing resources at DOE National Energy Research Scientific Computing Center and the Argonne Leadership Computing Facility (ALCF
They discovered that the amount of surface covered by the organic molecules and the moleculesmobility on the surface both have an important influence on the degree of asymmetry in the membrane. hese are said fascinating results
scientists could use this method to induce folding in any nanoparticle membrane that has an asymmetrical distribution of surface molecules.
ou use one type of molecule that hates water and rely on the water surfaces to drive the molecules to distribute non-uniformly,
or you could use two different kinds of molecules. The key is that the molecules have to distribute non-uniformly. he next step for Lin
and his colleagues is to explore how they can control the molecular distribution on the surface and therefore the folding behavior.
They envision zapping only a small part of the structure with the electron beam, designing the stresses to achieve particular bending patterns. ou can maybe fold these things into origami structures and all sorts of interesting geometries,
Lin said. t opens the possibilities. ource:
#Astronomers discover powerful aurora beyond solar system Astronomers have discovered the first aurora ever seen in an object beyond our Solar system.
including various forms of chemotherapy and radiation. What they lack, however, is good reconnaissance a reliable way to obtain real-time data about how well a particular therapy is working for any given patient.
Oxygen levels, meanwhile, can help doctors gauge the proper dose of a therapy such as radiation,
the more radiation you need, Cima says. o, these sensors, read over time, could let you see how hypoxia was changing in the tumor,
so you could adjust the radiation accordingly. The sensor housing, made of a biocompatible plastic,
The immune system attacks the invader with a number of reactive molecules designed to neutralize it,
However, these molecules can also cause collateral damage to healthy tissue around the infection site:
This lesion, a damaged form of the normal DNA base cytosine, is caused by the reactive molecule hypochlorous acid the main ingredient in household bleach
UK, have used a combination of small molecules to turn cells isolated from human skin into Schwann cells the specialised cells that support nerves and play a role in nerve repair.
and coaxed them into Schwann cells by exposing them to small molecules. e observed that the bulge,
and whether they could be used to generate Schwann cellssaid Sieber-Blum. e then used pertinent small molecules to either enhance
They are important for the cell ability to take up molecules and particles from the cell surface into the cell.
If this doesn work, the function of the cell is disturbed, resulting in diseases. Having too few invaginations is associated with atrial fibrillation.
Meteors (popularly known as hooting stars are the result of small particles, some as small as a grain of sand, entering the Earth atmosphere at high speed.
these particles heat the air around them, causing the characteristic streak of light seen from the ground.
and glowing air molecules that may take a few seconds to fade. Source: RA d
#A new look at superfluidity MIT physicists have created a superfluid gas, the so-called Bose-Einstein condensate, for the first time in an extremely high magnetic field.
At temperatures approaching absolute zero, atoms cease their individual, energetic trajectories, and start to move collectively as one wave.
Superfluids are thought to flow endlessly, without losing energy, similar to electrons in a superconductor. Observing the behavior of superfluids
if atoms cannot be kept cold or confined. The MIT team combined several techniques in generating ultracold temperatures,
the John D. Macarthur Professor of Physics at MIT. e use ultracold atoms to map out
originally co-developed by Ketterle, to cool atoms of rubidium to nanokelvin temperatures. Atoms of rubidium are known as bosons,
for their even number of nucleons and electrons. When cooled to near absolute zero bosons form what called a Bose-Einstein condensate a superfluid state that was discovered first co by Ketterle,
and for which he was awarded ultimately the 2001 Nobel prize in physics. After cooling the atoms,
the researchers used a set of lasers to create a crystalline array of atoms, or optical lattice.
The electric field of the laser beams creates what known as a periodic potential landscape, similar to an egg carton,
which mimics the regular arrangement of particles in real crystalline materials. When charged particles are exposed to magnetic fields,
their trajectories are bent into circular orbits, causing them to loop around and around. The higher the magnetic field, the tighter a particle orbit becomes.
However, to confine electrons to the microscopic scale of a crystalline material, a magnetic field 100 times stronger than that of the strongest magnets in the world would be required.
The group asked whether this could be done with ultracold atoms in an optical lattice. Since the ultracold atoms are charged not,
as electrons are, but are instead neutral particles, their trajectories are unaffected normally by magnetic fields. Instead, the MIT group came up with a technique to generate a synthetic
ultrahigh magnetic field, using laser beams to push atoms around in tiny orbits, similar to the orbits of electrons under a real magnetic field.
In 2013, Ketterle and his colleagues demonstrated the technique, along with other researchers in Germany, which uses a tilt of the optical lattice
and two additional laser beams to control the motion of the atoms. On a flat lattice, atoms can easily move around from site to site.
However, in a tilted lattice, the atoms would have to work against gravity. In this scenario, atoms could only move with the help of laser beams. ow the laser beams could be used to make neutral atoms move around like electrons in a strong magnetic field
added Kennedy. Using laser beams, the group could make the atoms orbit, or loop around, in a radius as small as two lattice squares, similar to how particles would move in an extremely high magnetic field. nce we had the idea,
we were excited really about it, because of its simplicity. All we had to do was take two suitable laser beams
and carefully align them at specific angles, and then the atoms drastically change their behavior,
Kennedy says. ew perspectives to known physics After developing the tilting technique to simulate a high magnetic field,
the group worked for a year and a half to optimize the lasers and electronic controls to avoid any extraneous pushing of the atoms,
which could make them lose their superfluid properties. t a complicated experiment, with a lot of laser beams, electronics,
and magnets, and we really had to get everything stable, Burton says. t took so long just to iron out all the details to eventually have this ultracold matter in the presence of these high fields,
and keep them cold some of it was painstaking work. In the end, the researchers were able to keep the superfluid gas stable for a tenth of a second.
During that time, the team took time-of-flight pictures of the distribution of atoms to capture the topology
or shape, of the superfluid. Those images also reveal the structure of the magnetic field something that been known,
but to add strong interactions between ultracold atoms, or to incorporate different quantum states, or spins.
Ketterle says such experiments would connect the research to important frontiers in material research, including quantum Hall physics
What if a fusion of computer science and psychology could help us understand more about how people learn,
However, they grow in random spots on germanium wafer in two different directions, which scientists have to control
properties directly on a conventional germanium semiconductor wafer. This discovery is aimed at allowing manufacturers of electronics to develop the next-generation of electronic devices that will have much greater performance.
Professor Michael Arnold, one of the authors of the study, said raphene nanoribbons that can be grown directly on the surface of a semiconductor like germanium are more compatible with planar processing that used in the semiconductor industry,
straight edges directly on germanium wafers. As scientists describe it, they are growing graphene in this shape via process called chemical vapour deposition.
Graphene is only one atom thick material, which conducts electricity and heat with such efficiency that it is likely to revolutionize electronics.
which adsorbs to the germanium surface and decomposes to form various hydrocarbons. Then these hydrocarbons react with each other
and form graphene on surface of the germanium wafer. Team of researchers made this discovery
Scientists found that at a very slow growth rate graphene naturally grows into long nanoribbons on a specific crystal facet of germanium
graphene grows at completely random spots on the germanium wafer. Furthermore, strips are oriented in two different directions on the surface.
and it degrades IFITM3 by attaching a small chain of molecules to it a common process of protein clearing called ubiquitination.
where the active drug molecules are extracted and refined into medicines. hen we started work a decade ago,
and break molecules, said Stephanie Galanie, a Phd student in chemistry and a member of Smolke team. heye the action heroes of biology. o get the yeast assembly line going,
Many plants, including opium poppies, produce (S)- reticuline, a molecule that is a precursor to active ingredients with medicinal properties.
a molecule that starts the plant down a path toward the production of molecules that can relieve pain.
in order to craft a molecule that emerged ready to plug pain receptors in the brain. Engineered with a purposein their Science paper,
but it would eliminate the time delay of growing poppies. he molecules we produced and the techniques we developed show that it is possible to make important medicines from scratch using only yeast,
Metal molecules within the contrast solution are magnetized during the MRI process and enhance the image wherever the molecules of solution bind with the targeted protein. he primary tumor sends signals to distant tissue
and organs to prepare the soil for metastasis, Lu said. y also binding with the magnetically tagged peptide,
Recently, researchers at Oxford university Department of Engineering science have been investigating mart gelsthat can switch from a stable gel to a liquid suspension of very small particles (a ol.
The scattering photons from the laser bounce off obstacles and make their way back to sensors in the camera.
The dimensions of that unseen space are recreated then based on the time stamp of the photons that scatter back to the camera.
and because of radiation, Velten says. ut in these caves, people could survive for a long time with consistent temperatures and no radiation.
Some of these may actually be quite deep, under 50-60 meters of rock. Assisted by chemical engineering undergraduate Jessica Zeman,
a Lawrence Berkeley National Laboratory (Berkeley Lab) researcher has invented a new technology to image single molecules with unprecedented spectral and spatial resolution,
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,
The research was reported in the journal Nature Methods in a paper titled, ltrahigh-throughput single-molecule spectroscopy and spectrally resolved super-resolution microscopy,
and spectrum of each individual molecule, plotting its super-resolved spatial position in two dimensions and coloring each molecule according to its spectral position,
Xu said. his 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. o we constructed a dual-objective system
but dispersed the single-molecule image collected by one objective lens into spectrum while keeping the other image for single-molecule localization Xu said. ow we are simultaneously accumulating the spectrum of the single molecules and also their position,
so we solved the conundrum. Next they dyed the sample with 14 different dyes in a narrow emission window and excited and photoswitched the molecules with one laser.
While the spectra of the 14 dyes are heavily overlapping since theye close in emission, they found that the spectra of the individual molecules were surprisingly different
and thus readily identifiable. hat useful because it means we had a way to do multicolor imaging within a very narrow emission window,
they were able to easily distinguish molecules of different dyes based on their spectral mean alone,
Diffusion MRI measures the movement of water molecules to create a visual representation of the brain axons.
which provided a picture of the orientation of moving water molecules. And, multi-shell imaging was used on 78 healthy adults to get similar images using different imaging parameters.
introducing certain types of ions or pushing ions out of the cells to alter electrical activity.
But without a feedback loop, scientists could only assume that the optical signals were having the effects desired
or brain region. e want to precisely control where photons are being sent to activate different cells, Newman said. ptogenetics allows genetic specification
and other types of cells that react to certain molecules typically associated with pathogensid not.
macrophages appear similar to wild-type macrophages that have been activated by exposure to molecules that occur commonly in infections.
by using a molecule found in the outer membrane of Gram-negative bacteria, called a lipopolysaccharidel. It made ATF7 phosphorylated
The team is currently working with industrial partners to create metasurfaces for use in commercial devices such as miniature cameras and spectrometers,
Gartner team makes use of a familiar molecule: DNA. The researchers incubate cells with tiny snippets of single stranded-dna DNA engineered to slip into the cellsouter membranes, covering each cell like the hairs on a tennis ball.
#Scientists queezelight one particle at a time A team of scientists has measured successfully particles of light being queezed in an experiment that had been written off in physics textbooks as impossible to observe.
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: t 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 oise 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. f you look at a flat surface,
Atature said. he same thing is happening with vacuum fluctuations. Once you get into the quantum world,
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 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,
below the standard baseline of vacuum fluctuations. This was done at the expense of making other parts of the electromagnetic field less measurable,
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,
the researchers etched micrometer scale pillars into a silicon surface using photolithography and deep reactive-ion etching,
#SLAC Ultrafast lectron Cameravisualizes Ripples in 2-D Material New research led by scientists from the Department of energy SLAC National Accelerator Laboratory
and Stanford university shows how individual atoms move in trillionths of a second to form wrinkles on a three-atom-thick material.
red) and probed the laser-induced structural changes with a subsequent electron pulse (probe pulse, blue).
The electrons of the probe pulse scatter off the monolayer atoms (blue and yellow spheres)
It was made possible with SLAC instrument for ultrafast electron diffraction (UED), which uses energetic electrons to take snapshots of atoms
and molecules on timescales as fast as 100 quadrillionths of a second. his is published the first scientific result with our new instrument,
said scientist Xijie Wang, SLAC UED team lead. t showcases the method outstanding combination of atomic resolution, speed and sensitivity.
This animation explains how researchers use high-energy electrons at SLAC to study faster-than-ever motions of atoms and molecules relevant to important materials properties and chemical processes.
or 2-D materials, contain just a single layer of molecules. In this form they can take on new and exciting properties such as superior mechanical strength
Until now, researchers only had limited a view of the underlying mechanisms. he functionality of 2-D materials critically depends on how their atoms move,
Researchers have used SLAC experiment for ultrafast electron diffraction (UED), one of the world fastest lectron cameras,
to take snapshots of a three-atom-thick layer of a promising material as it wrinkles in response to a laser pulse.
Because of this strong interaction with light, researchers also think they may be able to manipulate the material properties with light pulses. o engineer future devices,
which were prepared by Linyou Cao group at North carolina State university, into a beam of very energetic electrons.
The electrons, which come bundled in ultrashort pulses, scatter off the sample atoms and produce a signal on a detector that scientists use to determine where atoms are located in the monolayer.
This technique is called ultrafast electron diffraction. Illustrations (each showing a top and two side views) of a single layer of molybdenum disulfide (atoms shown as spheres.
Top left: In a hypothetical world without motions, the dealmonolayer would be flat. Top right:
In reality, the monolayer is wrinkled as shown in this room-temperature simulation. Bottom: If a laser pulse heats the monolayer up,
it sends ripples through the layer. These wrinkles, which researchers have observed now for the first time, have large amplitudes
finding a pharmaceutically active molecule is only half the battle: the drug must also be able to safely reach its target.
hollow particles that are secreted from many types of cells. They contain functional proteins and genetic materials and serve as a vehicle for communication between cells.
#Researchers develop key component for terahertz wireless Terahertz radiation could one day provide the backbone for wireless systems that can deliver data up to one hundred times faster than today cellular or Wi-fi networks.
As terahertz waves travel down the waveguide, some of the radiation leaks out of the slit.
On the other end, a receiver could be tuned to accept radiation at a particular angle,
in addition to attacking tumors directly, CAR T cells, like all T cells, release signaling molecules called cytokines, some
they can screen for small molecules or genes that can change a cell phenotype. For example, they could look for a drug that could change the hypermethylation that has been associated with a specific cancer.
inexpensive tests using DNA Chemists at the University of Montreal used DNA molecules to developed rapid,
when atoms are brought too close together to detect a wide array of protein markers that are linked to various diseases.
and blocks fusion of different viruses with host cells, said Liu. n HIV and AIDS research,
inexpensive tests using DNA Chemists at the University of Montreal used DNA molecules to developed rapid,
when atoms are brought too close together to detect a wide array of protein markers that are linked to various diseases.
and changes shape could lead to artificial arteries Researchers at Queen Mary University of London (QMUL) have developed a way of assembling organic molecules into complex tubular tissue-like structures without the use of moulds
Virendra Singh and Thomas Bougher constructed devices that utilize the wave nature of light rather than its particle nature.
enough to drive electrons out of the carbon nanotube antennas when they are excited by light. In operation, oscillating waves of light pass through the transparent calcium-aluminum electrode
allowing electrons generated by the antenna to flow one way into the top electrode. Ultra-low capacitance, on the order of a few attofarads, enables the 10-nanometer diameter diode to operate at these exceptional frequencies. rectenna is basically an antenna coupled to a diode
They have created a new type of lithium-ion battery anode using portabella mushrooms, which are inexpensive, environmentally friendly and easy to produce.
The current industry standard for rechargeable lithium-ion battery anodes is synthetic graphite, which comes with a high cost of manufacturing
Hierarchically Porous Carbon Anodes for Li-ion Batteries, published on Sept. 29 in the journal Nature Scientific Reports.
This paper involving mushrooms is published just over a year after the Ozkan labs developed a lithium-ion battery anode based on nanosilicon via beach sand as the natural raw material.
a nanomaterial consisting of graphite that is extremely thin measuring the thickness of a single atom.
#Physicists turn toward heat to study electron spin The quest to control and understand the intrinsic spin of electrons to advance nanoscale electronics is hampered by how hard it is to measure tiny, fast magnetic devices.
Applied physicists at Cornell offer a solution: using heat, instead of light, to measure magnetic systems at short length and time scales.
if perfected, could lead to a novel tabletop magnetic measurement technique and new, nanoscale electronic devices based on electrical spin, rather than charge.
Why the interest in electron spin? In physics, electron spin is established the well phenomenon of electrons behaving like a quantum version of a spinning top,
and the angular momentum of these little tops pointing por own. An emerging field called spintronics explores the idea of using electron spin to control
and store information using very low power. Technologies like nonvolatile magnetic memory could result with the broad understanding and application of electron spin.
Spintronics, the subject of the 2007 Nobel prize in Physics, is already impacting traditional electronics, which is based on the control of electron charge rather than spin. irect imaging is really hard to do,
Fuchs said. evices are tiny, and moving really fast, at gigahertz frequencies. Wee talking about nanometers and picoseconds.
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