#Single-catalyst water splitter produces clean-burning hydrogen 24/7 Array'We have developed a low-voltage, single-catalyst water splitter that continuously generates hydrogen and oxygen for more than 200 hours,
an exciting world-record performance,'said study co-author Yi Cui, an associate professor of materials science and engineering at Stanford and of photon science at the SLAC National Accelerator Laboratory.
In an engineering first, Cui and his colleagues used lithium-ion battery technology to create one low-cost catalyst that is capable of driving the entire water-splitting reaction.'
'Our group has pioneered the idea of using lithium-ion batteries to search for catalysts, 'Cui said.'
'Our hope is that this technique will lead to the discovery of new catalysts for other reactions beyond water splitting.'
'Arrayhydrogen has long been promoted as an emissions-free alternative to gasoline. Despite its sustainable reputation, most commercial-grade hydrogen is made from natural gas,
a fossil fuel that contributes to global warming. As an alternative, scientists have been trying to develop a cheap and efficient way to extract pure hydrogen from water.
A conventional water-splitting device consists of two electrodes submerged in a water-based electrolyte.
A low-voltage current applied to the electrodes drives a catalytic reaction that separates molecules of H2o, releasing bubbles of hydrogen on one electrode and oxygen on the other.
Each electrode is embedded with a different catalyst typically platinum and iridium, two rare and costly metals.
But in 2014, Stanford chemist Hongjie Dai developed a water splitter made of inexpensive nickel and iron that runs on an ordinary 1. 5-volt battery.
Arrayin the new study, Cui and his colleagues advanced that technology further.''Our water splitter is unique,
because we only use one catalyst, nickel-iron oxide, for both electrodes,'said graduate student Haotian Wang,
lead author of the study.''This bifunctional catalyst can split water continuously for more than a week with a steady input of just 1. 5 volts of electricity.
That's an unprecedented water-splitting efficiency of 82 percent at room temperature.''In conventional water splitters, the hydrogen and oxygen catalysts often require different electrolytes with different phone acidic,
one alkaline--to remain stable and active.''For practical water splitting, an expensive barrier is needed to separate the two electrolytes,
adding to the cost of the device, 'Wang said.''But our single-catalyst water splitter operates efficiently in one electrolyte with a uniform ph.'Wang
and his colleagues discovered that nickel-iron oxide, which is cheap and easy to produce,
is actually more stable than some commercial catalysts made of precious metals.''We built a conventional water splitter with two benchmark catalysts, one platinum and one iridium,
'Wang said.''At first the device only needed 1. 56 volts of electricity to split water,
but within 30 hours we had to increase the voltage nearly 40 percent. That's a significant loss of efficiency.'
'Arrayto find catalytic material suitable for both electrodes, the Stanford team borrowed a technique used in battery research called lithium-induced electrochemical tuning.
The idea is to use lithium ions to chemically break the metal oxide catalyst into smaller and smaller pieces.'
'Breaking down metal oxide into tiny particles increases its surface area and exposes lots of ultra-small,
interconnected grain boundaries that become active sites for the water-splitting catalytic reaction, 'Cui said.'
'This process creates tiny particles that are connected strongly, so the catalyst has very good electrical conductivity and stability.'
'Wang used electrochemical tuning--putting lithium in, taking lithium out to test the catalytic potential of several metal oxides.'
but having a single catalyst also reduces two sets of capital investment to one, 'Cui said.'
'We believe that electrochemical tuning can be used to find new catalysts for other chemical fuels beyond hydrogen.
The technique has been used in battery research for many years, but it's a new approach for catalysis. The marriage of these two fields is very powerful.'
'Other Stanford co-authors of the study are postdoctoral scholar Hyun-Wook Lee, visiting student Zhiyi Lu,
and graduate students Yong Deng, Po-Chun Hsu, Yayuan Liu and Dingchang Lin. Arra a
#New mechanism that regulates tumor initiation, invasion in skin basal cell carcinoma Researchers at the Université libre de Bruxelles,
ULB uncover a new mechanism that regulates tumour initiation and invasion in skin basal cell carcinoma.
Basal cell carcinoma (BCC) is the most common cancer found in human with several million of new patients affected every year around the world.
The mechanisms that control BCC initiation and invasion are known poorly. In a new study published in Cell Stem Cell,
Cédric Blanpain, MD/Phd, professor and WELBIO investigator at the IRIBHM, Université libre de Bruxelles
directly controls skin cancer formation by regulating the expansion of tumor initiating cells and the invasive properties of cancer cells.
Jean-Christophe Larsimont and colleagues used state of the art genetic mouse models to dissect the functional role
In collaboration with Pr Véronique Del Marmol (Department of Dermatology, Erasme Hospital, ULB) and the group of Pr François Fuks (Laboratory of cancer epigenetics, Faculty of medicine, ULB), Larsimont and colleagues demonstrated that
Sox9 begins to be expressed in pre-cancerous lesions and is maintained in invasive tumors. Deletion of Sox9 prevents skin cancer formation demonstrating the essential role of Sox9 during tumorigenesis
and leads to the progressive disappearance of the oncogene expressing cells.""It was really exciting to see that the deletion of only one gene was sufficient to completely prevent tumor formation.
It was even more surprising to observe that in absence of Sox9, pre-cancerous cells disappear over time,
suggesting that we can eliminate oncogene expressing cells before cancer formation"comments Jean-Christophe Larsimont, the first author of this study.
as well as the gene network regulated by Sox9 during the early steps of skin tumor initiation
cell adhesion and cytoskeleton dynamics required for tumor invasion. These results have important implications for the development of novel strategies to block tumor formation and invasion in the most frequent cancer in humans."
"Given that the majority of human cancers express Sox9, it is likely that the results of this study will be relevant for other cancers in humans
and will help to define new strategies to prevent cancer formation and block tumor invasion"comments Cédric Blanpain, the last and corresponding author of this study.
This work was supported by the FNRS, Fondation Contre le Cancer, Foundation ULB, ERC the Fonds Gaston Ithier, the Fond Yvonne Boël, the foundation Bettencourt Schueller,
and the foundation Baillet-Latour. Cédric Blanpain is an investigator of WELBIO o
#X marks the spot: Novel method for controlling plasma rotation confirmed Such a method could prove important for future facilities like ITER,
the huge international tokamak under construction in France that will demonstrate the feasibility of fusion as a source of energy for generating electricity.
ITER's massive size will make it difficult for the facility to provide sufficient rotation through external means.
Rotation is essential to the performance of all tokamaks. Rotation can stabilize instabilities in plasma,
and sheared rotation--the difference in velocities between two bands of rotating plasma--can suppress plasma turbulence,
making it possible to maintain the gas's high temperature with less power and reduced operating costs.
Today's tokamaks produce rotation mainly by heating the plasma with neutral beams which cause it to spin.
however, rotating particles that leak from the edge of the plasma accelerate the plasma in the opposite direction,
Stoltzfus-Dueck and his team influenced intrinsic rotation by moving the so-called X-point--the dividing point between magnetically confined plasma
and plasma that has leaked from confinement--on the Tokamak à Configuration Variable (TCV) in Lausanne, Switzerland.
The experiments marked the first time that researchers had moved the X-point horizontally to study plasma rotation.
The results confirmed calculations that Stoltzfus-Dueck had published in a 2012 paper showing that moving the X-point would cause the confined plasma to either halt its intrinsic rotation
but modified rotation within the superhot core of the plasma where fusion reactions occur. The results indicate that scientists can use the X-point as a"control knob"to adjust the inner workings of fusion plasmas,
much like changing the settings on itunes or a stereo lets one explore the behavior of music.
This discovery gives fusion researchers a tool to access different intrinsic rotation profiles and learn more about intrinsic rotation itself and its effect on confinement.
Along with the practical applications of his research, Stoltzfus-Dueck enjoys the purely intellectual aspect of his work."
"Why do plasmas rotate in the way they do? It's a puzzle. z
#Sweeping lasers snap together nanoscale geometric grids Now, scientists at the U s. Department of energy's Brookhaven National Laboratory have developed a new technique to rapidly create nano-structured grids for functional materials with unprecedented versatility."
"We can fabricate multi-layer grids composed of different materials in virtually any geometric configuration,
"said study coauthor and Brookhaven Lab scientist Kevin Yager.""By quickly and independently controlling the nanoscale structure and the composition,
we can tailor the performance of these materials. Crucially, the process can be adapted easily for large-scale applications."
"Arraythe scientists synthesized the materials at Brookhaven Lab's Center for Functional Nanomaterials (CFN) and characterized the nanoscale architectures using electron microscopy at CFN
and x-ray scattering at the National Synchrotron Light source--both DOE Office of Science User Facilities.
The new technique relies on polymer self-assembly, where molecules are designed to spontaneously assemble into desired structures.
Self-assembly requires a burst of heat to make the molecules snap into the proper configurations.
Here, an intensely hot laser swept across the sample to transform disordered polymer blocks into precise arrangements in just seconds."
"Self-assembled structures tend to automatically follow molecular preferences, making custom architectures challenging,"said lead author Pawel Majewski, a postdoctoral researcher at Brookhaven."
"Arrayfor the first step in grid construction, the team took advantage of their recent invention of laser zone annealing (LZA) to produce the extremely localized thermal spikes needed to drive ultra-fast self-assembly.
To further exploit the power and precision of LZA, the researchers applied a heat-sensitive elastic coating on top of the unassembled polymer film.
--which pulls and aligns the rapidly forming nanoscale cylinders.""The end result is that in less than one second,
who leads the Electronic nanomaterials group at CFN.""This order persists over macroscopic areas and would be difficult to achieve with any other method."
"To make these two-dimensional grids functional, the scientists converted the polymer base into other materials.
One method involved taking the nano-cylinder layer and dipping it into a solution containing metal salts.
These molecules then glom onto the self-assembled polymer, converting it into a metallic mesh.
A wide range of reactive or conductive metals can be used, including platinum, gold, and palladium.
where a vaporized material infiltrates the polymer nano-cylinders and transforms them into functional nanowires.
Arraythe first completed nanowire array acts as the foundation of the full lattice. Additional layers
each one following variations on that same process, are stacked then to produce customized, crisscrossing configurations--like chain-link fences 10,000 times thinner than a human hair."
"The direction of the laser sweeping across each unassembled layer determines the orientation of the nanowire rows,
and overlap shapes the grid. We then apply the functional materials after each layer forms.
"We can stack metals on insulators, too, embedding different functional properties and interactions within one lattice structure."
"For example, a single layer of platinum nanowires conducts electricity in only one direction, but a two-layer mesh conducts uniformly in all directions."
allowing it to drive polymer self-assembly even on top of complex underlying layers. This versatility enables the use of a wide variety of materials in different nanoscale configurations."
"We can generate nearly any two-dimensional lattice shape, and thus have a lot of freedom in fabricating multi-component nanostructures,
"Yager said.""It's hard to anticipate all the technologies this rapid and versatile technique will allow
and proliferation of these neuron-damaging compounds--a discovery that may accelerate the development of new drugs to treat this incurable disease.
The researchers added that the cell-to-cell"seeding"property of these mutant proteins seems to be a critical part of the disease's progression.
Study results appear online in Molecular Psychiatry. Huntington's disease is based a genetically, severe neurodegenerative disorder that results in progressive motor, cognitive and psychiatric impairment and, ultimately, death.
There is no effective treatment for Huntington's, which--like many neurodegenerative diseases--is characterized by an accumulation of misfolded mutant proteins that interfere with brain function.
As part of their study, the researchers introduced a new screening test that measures mutant huntingtin protein seeding in cerebrospinal fluid,
"Determining if a treatment modifies the course of a neurodegenerative disease like Huntington's or Alzheimer's may take years of clinical observation,
"said study leader Dr. Steven Potkin, UCI professor of psychiatry & human behavior.""This assay that reflects a pathological process can play a key role in more rapidly developing an effective treatment.
Seeding measurements can also aid in determining the optimal dosage of a new therapy. Additionally, gauging the seeding property of misfolded proteins may prove to be useful in the development of new treatments for other neurodegenerative diseases, such as Alzheimer's, ALS and Parkinson's.
UCI is a leading center for research on Huntington's disease and other related neurodegenerative disorders. Its scientists have helped identify mechanisms underlying HD
and are actively pursuing the creation of novel therapies. Earlier this year, study contributor Leslie Thompson of UCI's Sue & Bill Gross Stem Cell Research center and UCI MIND received a $5 million grant from the California Institute for Regenerative medicine to continue her CIRM
-funded effort to develop stem cell treatments for Huntington's disease. In this project, Thompson and her colleagues plan to create a therapy employing human embryonic stem cells that can be evaluated in clinical trials s
#New manufacturing approach slices lithium-ion battery cost in half An advanced manufacturing approach for lithium-ion batteries, developed by researchers at MIT and at a spinoff company called 24m,
promises to significantly slash the cost of the most widely used type of rechargeable batteries while also improving their performance
and making them easier to recycle.""We've reinvented the process, "says Yet-Ming Chiang, the Kyocera Professor of Ceramics at MIT and a cofounder of 24m (and previously a cofounder of battery company A123).
The existing process for manufacturing lithium-ion batteries, he says, has changed hardly in the two decades
since the technology was invented, and is inefficient, with more steps and components than are needed really.
The new process is based on a concept developed five years ago by Chiang and colleagues including W. Craig Carter, the POSCO Professor of Materials science and engineering.
In this so-called"flow battery,"the electrodes are suspensions of tiny particles carried by a liquid and pumped through various compartments of the battery.
The new battery design is a hybrid between flow batteries and conventional solid ones: In this version,
while the electrode material does not flow, it is composed of a similar semisolid, colloidal suspension of particles.
Chiang and Carter refer to this as a"semisolid battery.""Simpler manufacturing process This approach greatly simplifies manufacturing,
and also makes batteries that are flexible and resistant to damage, says Chiang, who is senior author of a paper in the Journal of Power Sources analyzing the tradeoffs involved in choosing between solid
and flow-type batteries, depending on their particular applications and chemical components. This analysis demonstrates that
while a flow battery system is appropriate for battery chemistries with a low energy density (those that can only store a limited amount of energy for a given weight), for high-energy density devices such as lithium-ion batteries,
the extra complexity and components of a flow system would add unnecessary extra cost. Almost immediately after publishing the earlier research on the flow battery,
Chiang says, "We realized that a better way to make use of this flowable electrode technology was to reinvent the lithium ion manufacturing process."
"Instead of the standard method of applying liquid coatings to a roll of backing material, and then having to wait for that material to dry before it can move to the next manufacturing step,
the new process keeps the electrode material in a liquid state and requires no drying stage at all.
Using fewer, thicker electrodes, the system reduces the conventional battery architecture's number of distinct layers,
as well as the amount of nonfunctional material in the structure, by 80 percent. Having the electrode in the form of tiny suspended particles instead of consolidated slabs greatly reduces the path length for charged particles as they move through the material--a property known as"tortuosity."
"A less tortuous path makes it possible to use thicker electrodes, which, in turn, simplifies production
and lowers cost. Bendable and foldable In addition to streamlining manufacturing enough to cut battery costs by half,
Chiang says, the new system produces a battery that is more flexible and resilient. While conventional lithium-ion batteries are composed of brittle electrodes that can crack under stress,
the new formulation produces battery cells that can be bent, folded or even penetrated by bullets without failing.
This should improve both safety and durability, he says. The company has made so far about 10
000 batteries on its prototype assembly lines, most of which are undergoing testing by three industrial partners, including an oil company in Thailand
and Japanese heavy-equipment manufacturer IHI Corp. The process has received eight patents and has 75 additional patents under review;
24m has raised $50 million in financing from venture capital firms and a U s. Department of energy grant. The company is initially focusing on grid-scale installations,
used to help smooth out power loads and provide backup for renewable energy sources that produce intermittent output, such as wind and solar power.
But Chiang says the technology is suited also well to applications where weight and volume are limited,
such as in electric vehicles. Another advantage of this approach, Chiang says, is that factories using the method can be scaled up by simply adding identical units.
With traditional lithium-ion production plants must be built at large scale from the beginning in order to keep down unit costs,
so they require much larger initial capital expenditures. By 2020, Chiang estimates that 24m will be able to produce batteries for less than $100 per kilowatt-hour of capacity.
Venkat Viswanathan, an assistant professor of mechanical engineering at Carnegie mellon University who was involved not in this work, says the analysis presented in the new paper"addresses a very important question of
when is it better to build a flow battery versus a static model. This paper will serve as a key tool for making design choices
and go-no go decisions.""Viswanathan adds that 24m's new battery design"could do the same sort of disruption to lithium ion batteries manufacturing as
what mini-mills did integrated to the steel mills.""In addition to Chiang, the Power Sources paper was authored co by graduate student Brandon Hopkins, mechanical engineering professor Alexander Slocum,
and Kyle Smith of the University of Illinois at Urbana-Champaign. The work was supported by the U s. Department of energy's Center for Energy storage Research,
based at Argonne National Laboratory in Illinois o
#Bionic eye clinical trial results show long-term safety, efficacy vision-restoring implant The three-year clinical trial results of the retinal implant popularly known as the"bionic eye,
"have proven the long-term efficacy, safety and reliability of the device that restores vision in those blinded by a rare, degenerative eye disease.
The findings show that the Argus II significantly improves visual function and quality of life for people blinded by retinitis pigmentosa.
They are being published online in Ophthalmology, the journal of the American Academy of Ophthalmology. Retinitis pigmentosa is an incurable disease that affects about 1 in 4
000 Americans and causes slow vision loss that eventually leads to blindness. The Argus II system was designed to help provide patients who have lost their sight due to the disease with some useful vision.
Through the device, patients with retinitis pigmentosa are able to see patterns of light that the brain learns to interpret as an image.
The system uses a miniature video camera stored in the patient's glasses to send visual information to a small computerized video processing unit which can be stored in a pocket.
This computer turns the image to electronic signals that are sent wirelessly to an electronic device implanted on the retina
the layer of light-sensing cells lining the back of the eye. The Argus II received Food and Drug Administration (FDA) approval as a Humanitarian Use Device (HUD) in 2013,
which is an approval specifically for devices intended to benefit small populations and/or rare conditions.
In Europe Argus II received the CE Mark in 2011 and was launched commercially in Italy, Germany, France, Spain, The netherlands, Switzerland and England.
To further evaluate the safety, reliability and benefit of the device, a clinical trial of 30 people, aged 28 to 77,
was conducted in the United states and Europe. All of the study participants had little or no light perception in both eyes.
The researchers conducted visual function tests using both a computer screen and real-world conditions, including finding
and touching a door and identifying and following a line on the ground. A Functional Low-vision Observer Rated Assessment (FLORA) was performed also by independent visual rehabilitation experts at the request of the FDA to assess the impact of the Argus II system on the subjects'everyday lives,
including extensive interviews and tasks performed around the home. The visual function results indicated that up to 89 percent of the subjects performed significantly better with the device.
-or surgery-related serious adverse events. After three years, there were no device failures. Throughout the three years, 11 subjects experienced serious adverse events, most
"This study shows that the Argus II system is a viable treatment option for people profoundly blind due to retinitis pigmentosa--one that can make a meaningful difference in their lives
M d.,lead author of the study and director of the clinical retina research unit At wills Eye Hospital."
including treatment for other diseases and eye injuries
#UVA fertilization discovery may lead to male contraceptive Groundbreaking new reproductive research has identified key molecular events that could be playing a critical role as sperm
A particular protein from within the sperm stays intact at the site of fusion. This protein--discovered by Herr's lab 15 years ago--remains in place
"explained Herr, a Phd in the Department of Cell biology.""You want to know which molecules are located precisely where,
"The research also sheds light on the formation of sperm, and Herr's findings again speak to the importance of the ESP1 protein.
#Biomanufacturing of Cds quantum dots A team of Lehigh University engineers have demonstrated a bacterial method for the low-cost, environmentally friendly synthesis of aqueous soluble quantum dot (QD) nanocrystals at room temperature.
along with a team of chemical engineering, bioengineering, and material science students present this novel approach for the reproducible biosynthesis of extracellular,
water-soluble QDS in the July 1 issue of the journal Green Chemistry. This is the first example of engineers harnessing nature's unique ability to achieve cost effective and scalable manufacturing of QDS using a bacterial process.
and cadmium sulfide to provide a route to low-cost, scalable and green synthesis of Cds nanocrystals with extrinsic crystallite size control in the quantum confinement range.
The solution yields extracellular, water-soluble quantum dots from low-cost precursors at ambient temperatures and pressure.
The result is Cds semiconductor nanocrystals with associated size-dependent band gap and photoluminescent properties. This biosynthetic approach provides a viable pathway to realize the promise of green biomanufacturing of these materials.
The Lehigh team presented this process recently to a national showcase of investors and industrial partners at the Techconnect 2015 World Innovation Conference and National Innovation Showcase in Washington
D c. June 14-17.""Biosynthetic QDS will enable the development of an environmentally-friendly, bio-inspired process unlike current approaches that rely on high temperatures, pressures, toxic solvents and expensive precursors,
"Berger says.""We have developed a unique, 'green'approach that substantially reduces both cost and environmental impact."
"Quantum dots, which have use in diverse applications such as medical imaging, lighting, display technologies, solar cells, photocatalysts, renewable energy and optoelectronics, are typically expensive and complicated to manufacture.
In particular, current chemical synthesis methods use high temperatures and toxic solvents, which make environmental remediation expensive and challenging.
This newly described process allows for the manufacturing of quantum dots using an environmentally benign process and at a fraction of the cost.
Whereas in conventional production techniques QDS currently cost $1, 000-$10, 000 per gram, the biomanufacturing technique cuts that cost to about $1-$10 per gram.
The substantial reduction in cost potentially enables large-scale production of QDS viable for use in commercial applications."
"We estimate yields on the order of grams per liter from batch cultures under optimized conditions,
and are able to reproduce a wide size range of Cds QDS, "said Steven Mcintosh.
The research is funded by the National Science Foundation's Division of Emerging Frontiers in Research
and Innovation (EFRI Grant No. 1332349) and builds on the success of the initial funding,
supplied by Lehigh's Faculty Innovation Grant (FIG) and Collaborative Research Opportunity Grant (CORE) programs.
the expansion of this work to include a wide range of other functional materials. Functional materials are controlled those with composition
size, and structure to facilitate desired interactions with light, electrical or magnetic fields, or chemical environment to provide unique functionality in a wide range of applications from energy to medicine.
Mcintosh said, "While biosynthesis of structural materials is established relatively well, harnessing nature to create functional inorganic materials will provide a pathway to a future environmentally friendly biomanufacturing based economy.
We believe that this work is the first step on this path
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