3-D printed'tissue'to help combat disease A bench-top brain that accurately reflects actual brain tissue would be significant for researching not only the effect of drugs,
but brain disorders like schizophrenia, and degenerative brain disease. Researchers have completed now 3-D printing a six-layered structure similar to brain tissue, in
which cells are placed accurately and remain in their designated layer. Researchers at the ARC Centre of Excellence for Electromaterials Science (ACES) have taken a step closer to meeting this challenge,
Pharmaceutical companies spend millions of dollars testing therapeutic drugs on animals only to discover in human trials that the drug has an altogether different level of effectiveness.
but brain disorders like schizophrenia, and degenerative brain disease. ACES Director and research author Professor Gordon Wallace said that the breakthrough is significant progress in the quest to create a bench-top brain that will enable important insights into brain function,
in addition to providing an experimental test bed for new drugs and electroceuticals.""We are still a long way from printing a brain
but the ability to arrange cells so as they form neuronal networks is a significant step forward,
"Professor Wallace said. To create their six-layered structure, researchers developed a custom bio-ink containing naturally occurring carbohydrate materials.
and developed for use in a standard cell culturing facility without the need for expensive bioprinting equipment.
"This study highlights the importance of integrating advances in 3d printing, with those in materials science, to realise a biological outcome,
"Professor Wallace said.""This paves the way for the use of more sophisticated printers to create structures with much finer resolution."
"Arra a
#What would the world look like to someone with a bionic eye? Various sight recovery therapies are being developed by companies around the world,
offering new hope for people who are blind. But little is known about what the world will look like to patients who undergo those procedures.
A new University of Washington study seeks to answer that question and offers visual simulations of what someone with restored vision might see.
The study concludes that while important advancements have been made in the field, the vision provided by sight recovery technologies may be very different from what scientists
what vision would be like after two different types of sight recovery therapies. Lead author Ione Fine,
a UW associate professor of psychology, said the simulations are unprecedented.""This is the first visual simulation of restored sight in any realistic form,
if they undergo sight restoration surgery, an invasive and costly procedure.""This is a really difficult decision to make,
"These devices involve long surgeries, and they don't restore anything close to normal vision. The more information patients have, the better."
Loss of rods and cones is the primary cause of vision loss in diseases such as macular degeneration or retinitis pigmentosa.
But those diseases leave most remaining neurons within the retina relatively intact, and various technologies under development aim to restore vision by targeting the surviving cells.
which enable vision by stimulating surviving cells with an array of electrodes placed on the retina,
and optogenetics, which insert proteins into the surviving retinal cells to make them light-sensitive. But the devices have a major shortcoming
"said Boynton, a UW psychology professor.""Electrically stimulating the retina excites all of these cells at the same time,
which is very different from how these cells respond to real visual input.""There are similar issues with optogenetics,
Boynton said.""The optogenetic proteins that are currently available produce sluggish responses over time, and they are limited in the number of different cell types that they can separately target,
"he said. These limitations in both technologies mean that patients may see fuzzy, comet-like shapes or blurred outlines,
Previous simulations of restored vision have used a"scoreboard model,"a grid of dots similar to the scoreboard at a football game, in
which each electrode produces a visible dot in space. Together, that collection of dots is intended to demonstrate what someone with restored vision will see.
Fine said better simulations can provide valuable information about how implants need to be improved to produce more natural vision."
we're just shooting in the dark in trying to improve these implants
#Small tilt in magnets makes them viable memory chips University of California, Berkeley, researchers have discovered a new way to switch the polarization of nanomagnets,
paving the way for high-density storage to move from hard disks onto integrated circuits. The advance, to be reported in the Proceedings of the National Academy of Sciences,
could lead to computers that turn on in an instant and operate with far greater speed and significantly less power.
A research team led by Sayeef Salahuddin, an associate professor of electrical engineering and computer sciences, has found that a slight tilt of the magnets makes them easy to switch without an external magnetic field.
This opens the door to a memory system that can be packed onto a microprocessor, a major step toward the goal of reducing energy dissipation in modern electronics."
"To reduce the power draw and increase the speed, we want to be able to manufacture a computer chip that includes memory
so that it is close to the computational action, "said Salahuddin.""However, the physics needed to create long-term storage are not compatible with integrated circuits."
"Creating and switching polarity in magnets without an external magnetic field has been a key focus in the field of spintronics.
Generating a magnetic field takes power and space, which is why magnets have not yet been integrated onto computer chips.
Instead, there are separate systems for long-term magnetic memory. These include a computer's hard disk drive where data are stored,
and the various kinds of random-access memory, or RAM, on the integrated circuits of the central processing unit, or CPU, where calculations and logic operations are performed.
A large portion of the energy used in computing is spent on transferring data from one type of memory to another.
Doing that quickly takes more energy and generates more heat. In past research Salahuddin and his colleagues found that directing electrical current through the rare metal tantalum creates polarity in magnets without an external magnetic field.
But the battle wasn't over. Packing a sufficient number of nanomagnets onto a chip meant aligning them perpendicularly,
but that vertical orientation negated the switching effects of tantalum.""We found that by tilting the magnet--just 2 degrees was enough--you get all the benefits of a high-density magnetic switch without the need for an external magnetic field,
"said Salahuddin n
#Quantum states in a nano-object manipulated using a mechanical system Scientists at The swiss Nanoscience Institute at the University of Basel have used resonators made from single-crystalline diamonds to develop a novel device in
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,
but also for more common problems involving maladaptive daily decisions about drug or alcohol use, gambling or credit card binges.
The researchers discovered the importance of this connection by working with rats trained to make choices between stimuli that would result in their receiving different amounts of rewards, after varying periods of time.
The rats were asked to choose between two identical visual shapes by pressing their nose against one of them on a touchscreen (similar to an ipad
in exchange for rewards in the form of sugar pellets. Like most humans, rats have a sweet tooth.
With time, rats learned to negotiate a trade-off between a small reward (1 sugar pellet) delivered immediately
and a large reward (4 sugar pellets) delivered after a delay. The researchers discovered that the average rat,
Importantly, lesions to other parts of the brain, including the prefrontal cortex, known to be involved in certain aspects of decision-making,
and those with brain disease,"said Prof. Yogita Chudasama, of Mcgill's Psychology department and the lead researcher on the paper."
to be a therapeutic target in human patient groups
#Missing piece surfaces in the puzzle of autism A study carried out by the Laboratoire Neurobiologie des Interactions Cellulaires et Neurophysiopathologie (CNRS/Aix-Marseille Université),
in collaboration with clinicians from Marseilles Public Hospitals (AP-HM) and scientists from the Salk Institute in San diego (US), has revealed a new gene that plays a crucial role during early development in humans and
whose under-expression may induce certain autistic traits. This work is published on 4 august 2015 in Molecular Psychiatry.
Understanding the mechanisms that underlie autism spectrum disorders (ASD), which affect 7. 6 million people according to the World health organization,
is a major challenge. Characterized by heterogeneous symptoms and a multifactorial origin, this complex condition evolves during brain development.
in order to determine new genes involved in this disease. Easily accessible from nasal biopsies, these cells--which belong to nerve tissues
and can differentiate into neurons--constitute an interesting model to identify the genes and proteins whose expression is deregulated in patients with ASD.
Through its involvement in this chemical pathway, MOCOS is thought to be active in the processes of immunity and inflammation,
In these different organisms, under-expression of the enzyme induced hypersensitivity to oxidative stress (i e. to the toxicity of free radicals), a smaller number of synapses and abnormal neurotransmission due to a reduction in the number of vesicles carrying neurotransmitters.
In view of the presence of MOCOS in many organs and its involvement in numerous biological and neurobiological functions
The involvement of this enzyme in susceptibility to oxidative stress, which has frequently been observed in autistic children, its association with gastrointestinal diseases
--which often accompany autistic disorders --and its role in nerve development and neurotransmission mean it is an ideal candidate for deregulation of its expression to lead to the abnormal brain development observed in ASD.
while revealing new clinical and biological disturbances in these patients. This work therefore opens new pathways for research
and provides an opportunity to understand the roles of MOCOS and its regulators. This should
in the longer term, lead to the development of therapeutic tools and new diagnostic methods d
Obtained in collaboration with Juanma Vaquerizas from the Max Planck Institute for Molecular Biomedicine (Münster, Germany),
and could increase the efficiency of reprogramming somatic cells to be used for applications in regenerative medicine n
#'Yolks'and'shells'improve rechargeable batteries One big problem faced by electrodes in rechargeable batteries, as they go through repeated cycles of charging
degrading the battery's performance over time. Now a team of researchers at MIT and Tsinghua University in China has found a novel way around that problem:
creating an electrode made of nanoparticles with a solid shell, and a"yolk"inside that can change size again and again without affecting the shell.
The innovation could drastically improve cycle life, the team says, and provide a dramatic boost in the battery's capacity and power.
The new findings, which use aluminum as the key material for the lithium-ion battery's negative electrode,
or anode, are reported in the journal Nature Communications, in a paper by MIT professor Ju Li and six others.
The use of nanoparticles with an aluminum yolk and a titanium dioxide shell has proven to be"the high-rate champion among high-capacity anodes"
the team reports. Most present lithium-ion batteries--the most widely used form of rechargeable batteries--use anodes made of graphite, a form of carbon.
Graphite has a charge storage capacity of 0. 35 ampere-hours per gram (Ah/g; for many years, researchers have explored other options that would provide greater energy storage for a given weight.
Lithium metal, for example, can store about 10 times as much energy per gram, but is extremely dangerous,
capable of short-circuiting or even catching fire. Silicon and tin have very high capacity,
"This expansion and contraction of aluminum particles generates great mechanical stress, which can cause electrical contacts to disconnect.
Also, the liquid electrolyte in contact with aluminum will always decompose at the required charge/discharge voltages,
forming a skin called solid electrolyte interphase (SEI) layer, 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.
That's where the idea of using confined aluminum in the form of a yolk-shell nanoparticle came in.
In the nanotechnology business there is a big difference between what are called"core-shell"and"yolk-shell"nanoparticles.
The former have a shell that is bonded directly to the core, but yolk-shell particles feature a void between the two--equivalent to where the white of an egg would be.
As a result, the"yolk"material can expand and contract freely, with little effect on the dimensions and stability of the"shell.""
"Li says,"that separates the aluminum from the liquid electrolyte"between the battery's two electrodes.
and the aluminum inside is protected from direct contact with the electrolyte. The team didn't originally plan it that way,
says Li, the Battelle Energy Alliance Professor in Nuclear Science and Engineering, who has a joint appointment in MIT's Department of Materials science and engineering."
"We came up with the method serendipitously, it was a chance discovery, "he says. The aluminum particles they used,
which are about 50 nanometers in diameter, naturally have oxidized an layer of alumina (Al2o3).""We needed to get rid of it,
because it's not good for electrical conductivity, "Li says. They ended up converting the alumina layer to titania (Tio2),
which reacts with titanium oxysulfate to form a solid shell of titanium hydroxide with a thickness of 3 to 4 nanometers.
the aluminum core continuously shrinks to become a 30-nm-across"yolk,,"which shows that small ions can get through the shell.
but the inside of the electrode remains clean with no buildup of the SEIS, proving the shell fully encloses the aluminum
The result is an electrode that gives more than three times the capacity of graphite (1. 2 Ah/g) at a normal charging rate
For applications that require a high power-and energy density battery, he says, "It's probably the best anode material available."
"Full cell tests using lithium iron phosphate as cathode have been successful, indicating ATO is quite close to being ready for real applications.
The research team included Sa Li, Yu Cheng Zhao, and Chang An Wang of Tsinghua University in Beijing and Junjie Niu, Kangpyo So,
and Chao Wang of MIT. The work was supported by the National Science Foundation and the National Natural science Foundation of China a
#Source of liver stem cells identified Howard hughes medical institute (HHMI) scientists have identified stem cells in the liver that give rise to functional liver cells.
The work solves a longstanding mystery about the origin of new cells in the liver,
which must constantly be replenished as cells die off, even in a healthy organ.""We've solved a very old problem,
and give rise to mature cells, even in the absence of injury or disease.""Nusse and his colleagues reported their findings August 5, 2015, in the journal Nature.
and minerals, removing toxins, and helping regulate fats and sugars in the bloodstream. As these cells die off,
so specialized to carry out the work of the liver, they have lost likely the ability to divide."
"Differentiated hepatocytes have amplified their chromosomes, "he explains. That is, the cells have more than the usual two copies of every chromosome."
"This enables the cells to make more proteins, but it really compromises their ability to divide."
Bruce Wang, a gastroenterologist at the Liver Center at the University of California, San francisco, led the experiments as a visiting scholar in Nusse's lab. Wang began by searching for fluorescently labeled
the labeled cells had only two copies of each chromosome. By following the descendents of the stem cells for up to a year,
taking on the specialized features and amplified genomes of mature hepatocytes.""This fits the definition of stem cells,
The lab is now investigating how the newly identified stem cells might contribute to regeneration of liver tissue after injury.
whether liver cancers tend to originate in these replicating cells, as opposed to more mature hepatocytes,
Horses and humans share facial expressions Horses share some surprisingly similar facial expressions to humans and chimps, according to new University of Sussex research.
as devised by the Sussex team in collaboration with researchers at the University of Portsmouth and Duquesne University, identified 17"action units"(discrete facial movements) in horses.
Co-lead author Professor Karen Mccomb said:""It was thought previously that, in terms of other species, the further away an animal was from humans,
#Molecular cell cycle clock discovered that controls stem cell potency Singapore scientists from A*STAR's Genome Institute of Singapore (GIS) have, for the first time,
This deeper understanding of how cells become differentiated is extremely important when considering therapeutic potentials.
"said lead author of the research, Dr Kevin Gonzales, Post Doctoral Fellow at the Stem Cell and Regenerative Biology at GIS."
"Moreover, most functional screens are carried out in mouse ESCS. The only functional screen on human ESCS was published in 2010 from our laboratory at the GIS.
This latest study was performed also on human ESCS, making it more clinically relevant than studies using mouse ESCS."
"Co-lead author Research Fellow Dr Liang Hongqing at GIS'Stem Cell and Regenerative Biology added,
"Our research has shifted the current paradigm from a G1-phase centric view in stem cell regulation to a balanced view that different cell cycle phases perform different roles to orchestrate the stem cell fate."
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.
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.
The method works because particles have a second nature: They also behave like waves. When electron waves pass through a sample,
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.
"LCLS expertise in electron gun technology and ultrafast laser systems gives our system the performance and stability needed to study much faster processes."
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."
"For instance, the researchers studied a single atomic layer of a material that is interesting for future electronic devices."
The scientists'ultimate goal is to turn UED into an ultrafast electron microscope--an instrument that would show details too small to be seen with an optical microscope.
Existing electron microscopes can already capture events in 10 billionths of a second, but with SLAC's instrument, the researchers hope to push the speed limit to processes that are 1, 000 times faster."
"In addition to researchers from SLAC and Stanford university, the research team included scientists from the University of Nebraska, Lincoln,
and the University of Duisburg-Essen in Germany n
#New 2d transistor material made using precision lasers Last year a multi-discipline research team led by South korea's Institute for Basic Science (IBS) Center for Integrated Nanostructure Physics
at Sungkyunkwan University (SKKU) director Young Hee Lee devised a fabrication method for the creation of pure Mote2.
Not only did succeed they in making Mote2 in pure form, they were able to make two types of it--a semiconducting variety called 2h-Mote2 (2h because of its hexagonal shape)
and it was seen by some as a black sheep of the transition metal dichalcogenides TMD) family and purposefully ignored.
and have an electrical property called a band gap, which makes them ideal for making electrical components, especially transistors.
A TMD crystal follows an MX2 format: there is one transition metal, represented by M m can be Tungsten, Molybdenum, etc.)
and two chalcogenides, the X2 (Sulfur, Selenium, or Tellurium. 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. The overwhelming majority of microchips that exist in electronics now are made from silicon,
and they work extremely well. However, as devices get smaller there is an increasing demand to shrink the size of the logic chips that make those devices work.
As the chips approach single or several atom thickness, (commonly referred to as 2-dimensional),
silicon no longer works as well as it does in a larger, 3-dimensional (3d) scale. As the scale approaches 2 dimensions (2d), the band gap of silicon changes (higher band gap than that of its 3d form)
and the contact points with metal connections on silicon are no longer smooth enough to be used efficiently in electrical circuits.
This is the perfect opportunity to employ new, exotic TMD materials. The IBS research team was able to exploit the two versions of Mote2
and make one 2d crystal that was composed of the semiconducting 2h-Mote2 and the metallic 1t'-Mote2.
This configuration is superior to using silicon as well as other 2d semiconductor because the boundary where the semiconducting (2h) and metallic (1t')Mote2 meet to have
what's called am ohmic homojunction. This is a connection that forms at the boundary between two different structural phases in a single material.
Despite one Mote2 state being a semiconductor and one being metallic, the team was able to create an ohmic homojunction between them,
making an extremely efficient connection. To do this, the team started with a piece of their pure 2h-Mote2
the team was able to create a 2d transistor that utilized an amalgamation of both the semiconducting properties of the 2h-Mote2 material as well as the high conductivity of the 1t'-Mote2.
By using only one material in the device channel and the metal-semiconductor junction, it is more energy efficient
metal electrodes can be applied to it directly, saving any additional work of finding a way to attach metal leads.
This new fabrication technique is a hyper-efficient way of utilizing the available Mote2 without any wasted or extraneous parts.
Professor Heejun Yang of SKKU said, "There are many candidates for 2d semiconductors, but Mote2 has a band gap of around 1 ev
which is similar to silicon's band gap and it allows an ohmic homojunction at the semiconductor-metal junctions."
"This means that Mote2 can replace silicon without much change in the current voltage configurations used with today's silicon technologies.
The dual-phase Mote2 transistor looks promising for use in new electronic devices as demand for components increases for materials that are small, light and extremely energy efficient e
#New research may enhance display, LED lighting technology Recently, quantum dots (QDS)--nano-sized semiconductor particles that produce bright, sharp,
color light--have moved from the research lab into commercial products like high-end TVS, e readers, laptops,
and even some LED lighting. However, QDS are expensive to make so there's a push to improve their performance and efficiency,
while lowering their fabrication costs. Researchers from the University of Illinois at Urbana-Champaign have produced some promising results toward that goal,
developing a new method to extract more efficient and polarized light from quantum dots (QDS) over a large-scale area.
Their method which combines QD and photonic crystal technology, could lead to brighter and more efficient mobile phone, tablet,
and computer displays, as well as enhanced LED lighting. With funding from the Dow chemical Company, the research team, led by Electrical & Computer engineering (ECE) Professor Brian Cunningham, Chemistry Professor Ralph Nuzzo,
and Mechanical Science & Engineering Professor Andrew Alleyne, embedded QDS in novel polymer materials that retain strong quantum efficiency.
They then used electrohydrodynamic jet (e-jet) printing technology to precisely print the QD-embedded polymers onto photonic crystal structures.
This precision eliminates wasted QDS, which are expensive to make. These photonic crystals limit the direction that the QD-generated light is emitted
an ECE graduate student and lead author of the research reported in Applied Physics Letters, their replica molded photonic crystals could someday lead to brighter, less expensive,
and more efficient displays.""Since screens consume large amounts of energy in devices like laptops, phones,
and tablets, our approach could have a huge impact on energy consumption and battery life, "she noted."
"If you start with polarized light, then you double your optical efficiency, "See explained.""If you put the photonic crystal-enhanced quantum dot into a device like a phone or computer,
then the battery will last much longer because the display would only draw half as much power as conventional displays."
"To demonstrate the technology, See fabricated a novel 1mm device (aka Robot Man) made of yellow photonic crystal-enhanced QDS.
The device is made of thousands of quantum dots, each measuring about six nanometers.""We made a tiny device,
but the process can easily be scaled up to large flexible plastic sheets, "See said.""We make one expensive'master'molding template that must be designed very precisely,
but we can use the template to produce thousands of replicas very quickly and cheaply
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