Articles from March 2015



NanoRobots Cross The Blood-Brain Barrier

Magnetic nanoparticles can open the blood-brain barrier and deliver molecules directly to the brain, say researchers from the University of Montreal, Polytechnique Montréal, and CHU Sainte-Justine. This barrier runs inside almost all vessels in the brain and protects it from elements circulating in the blood that may be toxic to the brain. The research is important as currently 98% of therapeutic molecules are also unable to cross the blood-brain barrier.

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The barrier is temporary opened at a desired location for approximately 2 hours by a small elevation of the temperature generated by the nanoparticles when exposed to a radio-frequency field,” explained first author and co-inventor Seyed Nasrollah Tabatabaei. “Our tests revealed that this technique is not associated with any inflammation of the brain. This new result could lead to a breakthrough in the way nanoparticles are used in the treatment and diagnosis of brain diseases,” explained the co-investigator, Hélène Girouard. “At the present time, surgery is the only way to treat patients with brain disorders. Moreover, while surgeons are able to operate to remove certain kinds of tumors, some disorders are located in the brain stem, amongst nerves, making surgery impossible,” added collaborator and senior author Anne-Sophie Carret.

The technology will be soon tested in humans and  the researchers are confident that future research will enable its use in people. “ This technology proposes a modern version of the vision described almost 40 years ago in the movie Fantastic Voyage, where a miniature submarine navigated in the vascular network to reach a specific region of the brain,” said principal investigator Sylvain Martel. In earlier research, Martel and his team had managed to manipulate the movement of nanoparticles through the body using the magnetic forces generated by magnetic resonance imaging (MRI) machines.

Source: http://www.nouvelles.umontreal.ca/

Under Attack Robots Dance To Stay On Feet

It’s another day of abuse for this poor robot named Atrias. If not being kicked around, Atrias spends hours being pummelled by balls. But, remarkably, through the abuse, the robot stays on its feet. Unlike most bipedal robots which are designed to move like humans, researchers at Oregon State University modelled Atrias after a bird, creating what’s basically a robotic ostrich that conserves energy while maximizing agility and balance.
atrias CLICK ON THE IMAGE TO ENJOY THE ROBOT DANCE
Atrias is fitted with two constantly moving pogo stick-like legs made of carbon fiber. Fiberglass springs store the mechanical energy produced while the robot makes unsuccessful attempts to avoid the punishment it receives from its creators. The researchers say that with a few more tweaks, the robots bird-like design will allow it to become the fastest two-legged robot ever built.
Atrias is funded by the U.S. Defense Department’s research arm, DARPA, who hope the robot will one day be able to work in hazard zones too dangerous for humans. But until that day comes – Atrias will just have to keep on taking the abuse — all in the name of science.
Source: http://mime.oregonstate.edu/

Cheap Batteries For Hydrogen Electric Car

Electrochemical devices are crucial to a green energy revolution in which clean alternatives replace carbon-based fuels. This revolution requires conversion systems that produce hydrogen from water or rechargeable batteries that can store clean energy in cars. Now, Singapore-based researchers have developed improved catalysts as electrodes for efficient and more durable green energy devices.

Electrochemical devices such as batteries use chemical reactions to create and store energy. One of the cleanest reactions is the conversion from water into oxygen and hydrogen. Using energy from the sun, water can be converted into those two elements, which then store this solar energy in gaseous form. Burning hydrogen leads to a chemical explosion that produces water.

For technical applications, the conversion from hydrogen and oxygen into water is done in fuel cells, while some rechargeable batteries use chemical reactions based on oxygen to store and release energy. A crucial element for both types of devices is the cathode, which is the electrical contact where these reactions take place. The research team, which included Zhaolin Liu and colleagues from the A*STAR Institute of Materials Research and Engineering with colleagues from Nanyang Technological University and the National University of Singapore, combined nanometer-sized crystals of this material with sheets of carbon or carbon nanotubes.

oxyde-carbon compositesOxide/carbon composites could power green metal-air batteries

The cost is estimated to be tens of times cheaper than the platinum/carbon composites used at present,” says Liu. Because platinum is expensive, intensive efforts are being made to find alternative materials for batteries.

Source:: http://www.research.a-star.edu.sg/

Smart Bandage

Engineers at UC Berkeley are developing a new type of bandage that does far more than stanch the bleeding from a paper cut or scraped knee.

Associate professor Michel Maharbiz explains how the smart bandage works to detect bedsores. (UC Berkeley video by Roxanne Makasdjian and Phil Ebiner)
Thanks to advances in flexible electronics, the researchers, in collaboration with colleagues at UC San Francisco, have created a new “smart bandage” that uses electrical currents to detect early tissue damage from pressure ulcers, or bedsores, before they can be seen by human eyes – and while recovery is still possible.
The researchers exploited the electrical changes that occur when a healthy cell starts dying. They tested the thin, non-invasive bandage on the skin of rats and found that the device was able to detect varying degrees of tissue damage consistently across multiple animals.

smartbandage The smart bandage is fabricated by printing gold electrodes onto a thin piece of plastic. This flexible sensor uses impedance spectroscopy to detect bedsores that are invisible to the naked eye
We set out to create a type of bandage that could detect bedsores as they are forming, before the damage reaches the surface of the skin,” said Michel Maharbiz, a UC Berkeley associate professor of electrical engineering and computer sciences and head of the smart-bandage project. “We can imagine this being carried by a nurse for spot-checking target areas on a patient, or it could be incorporated into a wound dressing to regularly monitor how it’s healing.
The findings, published in the journal Nature Communications, could provide a major boost to efforts to stem a health problem that affects an estimated 2.5 million U.S. residents at an annual cost of $11 billion.

Source: http://newscenter.berkeley.edu/

How To process Graphene To Produce Solar Cells

A new technique invented at the California Institute of Technology (Caltech) to produce graphene — a material made up of an atom-thick layer of carbon, at room temperature, could help pave the way for commercially feasible graphene-based solar cells and light-emitting diodes, large-panel displays, and flexible electronics.

With this new technique, we can grow large sheets of electronic-grade graphene in much less time and at much lower temperatures,” says Caltech staff scientist David Boyd, who developed the method. Boyd is the first author of a new study, published in the journal Nature Communications, detailing the new manufacturing process and the novel properties of the graphene it produces.

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Graphene revolutionizes a variety of engineering and scientific fields due to its unique properties, which include a tensile strength 200 times stronger than steel and an electrical mobility that is two to three orders of magnitude better than silicon. The electrical mobility of a material is a measure of how easily electrons can travel across its surface. However, achieving these properties on an industrially relevant scale has proven to be complicated. Existing techniques require temperatures that are much too hot — 1,800 degrees Fahrenheit, or 1,000 degrees Celsius — for incorporating graphene fabrication with current electronic manufacturing. Additionally, high-temperature growth of graphene tends to induce large, uncontrollably distributed strain—deformation—in the material, which severely compromises its intrinsic properties.

Previously, people were only able to grow a few square millimeters of high-mobility graphene at a time, and it required very high temperatures, long periods of time, and many steps,” says Caltech physics professor Nai-Chang Yeh, the Fletcher Jones Foundation Co-Director of the Kavli Nanoscience Institute and the corresponding author of the new study. “Our new method can consistently produce high-mobility and nearly strain-free graphene in a single step in just a few minutes without high temperature. We have created sample sizes of a few square centimeters, and since we think that our method is scalable, we believe that we can grow sheets that are up to several square inches or larger, paving the way to realistic large-scale applications.”

Source: http://www.caltech.edu/

Nanoparticles Destroy Acne

Acne, a scourge of adolescence, may be about to meet its ultra high-tech match. By using a combination of ultrasound, gold-covered particles and lasers, researchers from UC Santa Barbara (UCSB) and the private medical device company Sebacia have developed a targeted therapy that could potentially lessen the frequency and intensity of breakouts, relieving acne sufferers the discomfort and stress of dealing with severe and recurring pimples.

“Through this unique collaboration, we have essentially established the foundation of a novel therapy,” said Samir Mitragotri, professor of chemical engineering at UCSB.

The new technology builds on Mitragotri’s specialties in targeted therapy and transdermal drug delivery. Using low-frequency ultrasound, the therapy pushes gold-coated silica particles through the follicle into the sebaceous glands. Postdoctoral research associate Byeong Hee Hwang, now an assistant professor at Incheon National University, conducted research at UCSB.

Acne nanoparticleThe particles are delivered into the sebaceous gland by the ultrasound, and are heated by the laser. The heat deactivates the gland

The unique thing about these particles is that when you shine a laser on them, they efficiently convert light into heat via a process called surface plasmon resonance,” said Mitragotri. This also marks the first time ultrasound, which has been proved for years to deliver drugs through the skin, has been used to deliver the particles into humans.
Source: http://www.news.ucsb.edu/

How To Split Water At Low Cost To Produce Hydrogen

UNSW (Australia) scientists have developed a highly efficient oxygen-producing electrode for splitting water that has the potential to be scaled up for industrial production of clean energy fuel, hydrogen. This breaktrough is important for the future development of hydrogen electric cars (H mobil). The new technology is based on an inexpensive, specially coated foam material that lets the bubbles of oxygen escape quickly. Inefficient and costly oxygen-producing electrodes are one of the major barriers to the widespread commercial production of hydrogen by electrolysis, where the water is split into hydrogen and oxygen using an electrical current.

watersplitting Electrode

Our electrode is the most efficient oxygen-producing electrode in alkaline electrolytes reported to date, to the best of our knowledge,” says Associate Professor Chuan Zhao, of the UNSW School of Chemistry. “It is inexpensive, sturdy and simple to make, and can potentially be scaled up for industrial application of water splitting.”

The research, by Associate Professor Zhao and Dr Xunyu Lu, is published in the journal Nature Communications.

Source: http://www.newsroom.unsw.edu.au/

Electric Car Race: The Rise Of Formula E

Downtown Miami has been converted into a race track. Cement blocks, fencing and grandstands are all in place for the first electric car race ever held on U.S. soil. Miami is the fifth of ten cities around the world to host during the inaugural year of the Formula E Championship, a fully electric race car series. Teams of mechanics are preparing their electric cars for Saturday’s race. Mark Schneider from Team Audi ABT says Formula E is in many ways similar to Formula 1. The cars are fast, the suspense on race day is high, but instead of the roar of a gasoline powered engines, these electric cars let out a high pitched hum as they barrel down the track. Schneider says pits stop are a bit different as well.
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We do a pit stops like other racing series but when formula 1 changes tires we change cars. So we have two cars for each driver and after roughly half an hour the driver gets into the pits, jumps out of the car, jumps into another car and goes out again“, says Mark Schneider. Each car is powered by a massive lithium ion battery that makes up a third of the cars overall weight. Formula E CEO Alejandro Agag says with time those batteries will become more efficient and smaller allowing them to power a single car for an entire race. He says the concept behind formula E is to drive research and development in the electric automotive space to new heights.

Formula 1, Indy Car, NASCAR are places where new technologies have been developed that then have been used on road cars and we want Formula E to be the place that happens for the electric car,” he noticed. Along with innovations on the track, Agag says he wants to attract young fans to Formula E by utilizing technology off the track as well. He says plans are in the works to develop an interactive virtual track that will allow people to compete on race day from their homes. He concludes: “So if you are a kid at home you can play with the virtual car, a shadow car, against the real racers in real time.
Source: http://www.reuters.com/

How To Print Solar Cells Massively

Flexible optoelectronic devices that can be produced roll-to-roll – much like newspapers are printed – are a highly promising path to cheaper devices such as solar cells and LED lighting panels. Scientists from “TREASORES” European project present prototype flexible solar cell modules as well as novel silver-based transparent electrodes that outperform currently used materials.

printes solar cells
A flexible organic solar cell from TREASORES project undergoing mechanical testing: the cell is repeatedly flexed to a 25 mm radius whilst monitoring its performance. Such cells have shown lifetimes in excess of 4000 hours

In order to make solar energy widely affordable scientists and engineers all over the world are looking for low-cost production technologies. Flexible organic solar cells have a huge potential in this regard because they require only a minimum amount of (rather cheap) materials and can be manufactured in large quantities by roll-to-roll (R2R) processing. This requires, however, that the transparent electrodes, the barrier layers and even the entire devices be flexible. With these «ultra-flat» electrodes record efficiencies of up to 7% were obtained for organic solar cells using commercially available materials for light harvesting.
Source: http://www.empa.ch/

Electric Car: How To Increase the Batteries Life-Span

Drexel University (Philadephia) researchers, along with colleagues at Aix-Marseille University in France, have discovered a high performance cathode material with great promise for use in next generation lithium-sulfur batteries that could one day be used to power mobile devices and electric cars.

Lithium-sulfur batteries have recently become one of the hottest topics in the field of energy storage devices due to their high energy density — which is about four times higher than that of lithium-ion batteries currently used in mobile devices. One of the major challenges for the practical application of lithium-sulfur batteries is to find cathode materials that demonstrate long-term stability.

An international research collaboration led by Drexel’s Yury Gogotsi, PhD, professor in the College of Engineering and director of its Nanomaterials Research Group, has created a two-dimensional carbon/sulfur nanolaminate that could be a viable candidate for use as a lithium-sulfur cathode.
Tesla-Model-S One of the major challenges for the practical application of lithium-sulfur batteries is to find cathode materials that demonstrate long-term stability.

The carbon/sulfur nanolaminates synthesized by Gogotsi’s group demonstrate the same uniformity as the infiltrated carbon nanomaterials, but the sulfur in the nanolaminates is uniformly deposited in the carbon matrix as atomically thin layers and a strong covalent bonding between carbon and sulfur is observed. This may have a significant impact on increasing the life-span of next generation batteries.

In a paper they recently published in the chemistry journal Angewandte Chemie, Gogotsi, along with his colleagues at Aix-Marseille University explain their process for extracting the nanolaminate from a three-dimensional material called a Ti2SC MAX phase.
Source: http://drexel.edu

“Indolent” Or Deadly Prostate Cancer ?

A Northwestern University-led study in the emerging field of nanocytology could one day help men make better decisions about whether or not to undergo aggressive prostate cancer treatments.

Technology developed by Northwestern University researchers may help solve that quandary by allowing physicians to identify which nascent cancers are likely to escalate into potentially life-threatening malignancies and which ones will remainindolent,” or non-aggressive.

The prostate-specific antigen (PSA) test was once the recommended screening tool for detecting prostate cancer, but there is now disagreement over the use of this test because it can’t predict which men with elevated PSA levels will actually develop an aggressive form of the disease.
prostate cancer
If we can predict a prognosis with our technology, then men will know if their cancer is dangerous and if they should seek treatment,” said Vadim Backman, senior author of the study. “Right now there is no perfect tool to predict a prognosis for prostate cancer. Our research is preliminary, but it is promising and proves that the concept works.”

Backman is a professor of biomedical engineering at Northwestern’s McCormick School of Engineering and Applied Science.

The study, which includes researchers from Northwestern, NorthShore University HealthSystem (NorthShore) and Boston Medical Center, was published online in PLOS ONE.
source: http://www.northwestern.edu/

Graphene Fights Cavities and Gum Disease

Dental diseases, which are caused by the overgrowth of certain bacteria in the mouth, are among the most common health problems in the world. Now scientists have discovered that a material called graphene oxide is effective at eliminating these bacteria, some of which have developed antibiotic resistance. They report the findings in the journal ACS Applied Materials & Interfaces.
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Zisheng Tang and colleagues at Shanghai Jiao Tong University point out that dentists often prescribe traditional antibiotics to get rid of bacteria that cause tooth decay or gum disease. But with the rise in antibiotic resistance, new approaches are needed to address these problems, which can lead to tooth loss. Previous studies have demonstrated that graphene oxide — carbon nanosheets studded with oxygen groups — is a promising material in biomedical applications. It can inhibit the growth of some bacterial strains with minimal harm to mammalian cells. Tang’s team wanted to see if the nanosheets would also stop the specific bacteria that cause dental diseases.

In the lab, the researchers tested the material against three different species of bacteria that are linked to tooth decay and gum disease. By destroying the bacterial cell walls and membranes, graphene oxide effectively slowed the growth of the pathogens. The researchers conclude that the nanosheets could have potential uses in dental care.

According to the World Health Organization (WHO), oral health is essential to general health and quality of life.

Source: http://www.acs.org/