Research paves the way for alloys that are 3x stronger than steel yet bend like gum Abstract:
based on UNSW Australia research that can predict for the first time which combinations of metals will best form these useful materials.
Just like something from science fiction-think of the Liquid-Metal Man robot assassin (T-1000) in the Terminator films-these materials behave more like glass or plastic than metal.
While still being metals, they become as malleable as chewing gum when heated and can be moulded easily
They are also three times stronger and harder than ordinary metals on average, and are among the toughest materials known."
"They have been described as the most significant development in materials science since the discovery of plastics more than 50 years ago,"says study author, Dr Kevin Laws, from UNSW Australia in Sydney.
Most metals are crystalline when solid, with their atoms arranged in a highly organised and regular manner.
Metallic glass alloys, however, have disordered a highly structure, with the atoms arranged in a non-regular way."
"There are many types of metallic glass, with the most popular ones based on zirconium, palladium, magnesium, titanium or copper.
But until now, discovering alloy compositions that form these materials has required a lengthy process of trial and error in the laboratory,
They have used their model to successfully predict more than 200 new metallic glass alloys based on magnesium
"Metallic glass alloys are expensive to manufacture and to date have only been used in niche products,
such as ejector pins for iphones, watch springs for expensive hand-wound watches, trial medical implants,
They are planned also for use in the next Mars rover vehicle.""But if they become easier and cheaper to make,
they could be used widely in many applications including as exceptionally strong components in personal electronic devices, in space exploration vehicles,
and as hydrogen storage materials in next generation batteries
#Targeted drug delivery with these nanoparticles can make medicines more effective: Nanoparticles wrapped inside human platelet membranes serve as new vehicles for targeted drug delivery The research,
led by nanoengineers at the UC San diego Jacobs School of engineering, was published online Sept. 16 in Nature.""This work addresses a major challenge in the field of nanomedicine:
targeted drug delivery with nanoparticles, "said Liangfang Zhang, a nanoengineering professor at UC San diego and the senior author of the study."
"Because of their targeting ability, platelet-mimicking nanoparticles can directly provide a much higher dose of medication specifically to diseased areas without saturating the entire body with drugs."
"The study is an excellent example of using engineering principles and technology to achieve"precision medicine,
"said Shu Chien, a professor of bioengineering and medicine, director of the Institute of Engineering in Medicine at UC San diego,
and a corresponding author on the study.""While this proof of principle study demonstrates specific delivery of therapeutic agents to treat cardiovascular disease and bacterial infections,
it also has broad implications for targeted therapy for other diseases such as cancer and neurological disorders,"said Chien.
The ins and outs of the platelet copycats On the outside, platelet-mimicking nanoparticles are cloaked with human platelet membranes,
which enable the nanoparticles to circulate throughout the bloodstream without being attacked by the immune system. The platelet membrane coating has another beneficial feature:
it preferentially binds to damaged blood vessels and certain pathogens such as MRSA bacteria, allowing the nanoparticles to deliver
and release their drug payloads specifically to these sites in the body. Enclosed within the platelet membranes are made nanoparticle cores of a biodegradable polymer that can be metabolized safely by the body.
The nanoparticles can be packed with many small drug molecules that diffuse out of the polymer core and through the platelet membrane onto their targets.
To make the platelet-membrane-coated nanoparticles, engineers first separated platelets from whole blood samples using a centrifuge.
The platelets were processed then to isolate the platelet membranes from the platelet cells. Next the platelet membranes were broken up into much smaller pieces and fused to the surface of nanoparticle cores.
The resulting platelet-membrane-coated nanoparticles are approximately 100 nanometers in diameter, which is one thousand times thinner than an average sheet of paper.
This cloaking technology is based on the strategy that Zhang's research group had developed to cloak nanoparticles in red blood cell membranes.
The researchers previously demonstrated that nanoparticles disguised as red blood cells are capable of removing dangerous pore-forming toxins produced by MRSA, poisonous snake bites and bee stings from the bloodstream.
By using the body's own platelet membranes the researchers were able to produce platelet mimics that contain the complete set of surface receptors,
antigens and proteins naturally present on platelet membranes. This is unlike other efforts, which synthesize platelet mimics that replicate one or two surface proteins of the platelet membrane."
"Our technique takes advantage of the unique natural properties of human platelet membranes, which have a natural preference to bind to certain tissues
and organisms in the body,"said Zhang. This targeting ability, which red blood cell membranes do not have,
makes platelet membranes extremely useful for targeted drug delivery, researchers said. Platelet copycats at work In one part of this study, researchers packed platelet-mimicking nanoparticles with docetaxel,
a drug used to prevent scar tissue formation in the lining of damaged blood vessels, and administered them to rats afflicted with injured arteries.
Researchers observed that the docetaxel-containing nanoparticles selectively collected onto the damaged sites of arteries
and healed them. When packed with a small dose of antibiotics platelet-mimicking nanoparticles can also greatly minimize bacterial infections that have entered the bloodstream and spread to various organs in the body.
Researchers injected nanoparticles containing just one-sixth the clinical dose of the antibiotic vancomycin into one of group of mice systemically infected with MRSA bacteria.
The organs of these mice ended up with bacterial counts up to one thousand times lower than mice treated with the clinical dose of vancomycin alone."
"Our platelet-mimicking nanoparticles can increase the therapeutic efficacy of antibiotics because they can focus treatment on the bacteria locally without spreading drugs to healthy tissues
"We hope to develop platelet-mimicking nanoparticles into new treatments for systemic bacterial infections and cardiovascular disease."
"This work is supported by the National institutes of health and partially by the Defense Threat Reduction Agency Joint Science and Technology Office for Chemical and Biological Defense.
The collaborative effort also includes Kang Zhang, a professor of ophthalmology and chief of Ophthalmic Genetics at UC San diego and a corresponding author on this study y
#Portable Nanosensors Help Early Diagnosis of Breast cancer Tumors The nanosensor will be able to help the early diagnosis of breast cancer tumors even at very tiny dimensions after the completion of tests
The aim of the research was to facilitate the diagnosis of cancer tumors, including breast cancer, without the need for advanced clinical devices.
A portable nanosensor was designed and simulated in this research for the early and easy diagnosis of breast tumors.
The nanosensor consists of plasmonic nanoparticles that are placed at regular distance from each other. Based on the results of the modeling
the sensor is very sensitive to changes in electromagnetic fields that are dispersed with different tissues (normal and tumor.
The role of nanosensor between body surface and the detector is to strengthen the signal and taking samples through plasmonic effects of nanoparticles.
The throughputs of waves are different through natural and tumor tissues. Therefore, the interaction of tissues with electromagnetic waves created by a similar electrical field ends in different results.
It means a non-consistency happens in the profile received from the interaction of emitted light and various healthy and cancer tissues.
The meaningful signal is a tool for the detection of tumor tissue e
#Pushing the limits of lensless imaging: At the Frontiers in Optics conference researchers will describe a custom-built ultrafast laser that could help image everything from semiconductor chips to cells in real time Using ultrafast beams of extreme ultraviolet light streaming at a 100,000 times a second, researchers
from the Friedrich Schiller University Jena, Germany, have pushed the boundaries of a well-established imaging technique.
Not only did they make the highest resolution images ever achieved with this method at a given wavelength,
they also created images fast enough to be used in real time. Their new approach could be used to study everything from semiconductor chips to cancer cells.
The team will present their work at the Frontiers in Optics The Optical Society's annual meeting and conference in San jose, California, USA, on 22 october 2015.
and find their way onto a detector, creating a diffraction pattern. By analyzing that pattern,
a computer then reconstructs the path those photons must have taken, which generates an image of the target material--all without the lens that's required in conventional microscopy."
"The computer does the imaging part--forget about the lens, "explained Michael Zürch, Friedrich Schiller University Jena, Germany and lead researcher."
"The computer emulates the lens.""Without a lens, the quality of the images primarily depends on the radiation source.
Traditionally, researchers use big, powerful X-ray beams like the one at the SLAC National Accelerator Laboratory in Menlo Park, California, USA.
the detector must be placed close to the target material--similar to placing a specimen close to a microscope to boost the magnification.
hardly any photons will bounce off the target at large enough angles to reach the detector.
Zürch and a team of researchers from Jena University used a special, custom-built ultrafast laser that fires extreme ultraviolet photons a hundred times faster than conventional table-top machines.
With more photons, at a wavelength of 33 nanometers, the researchers were able to make an image with a resolution of 26 nanometers--almost the theoretical limit."
When taking snapshots every second, the researchers reached a resolution below 80 nanometers. The prospect of high-resolution and real-time imaging using such a relatively small setup could lead to all kinds of applications,
Engineers can use this to hunt for tiny defects in semiconductor chips. Biologists can zoom in on the organelles that make up a cell.
Eventually he said, the researchers might be able to cut down on the exposure times even more
#University of Houston researchers create fatigue-free, stretchable conductor: Material moves foldable electronics, new implantable medical devices a step closer Abstract:
Researchers have discovered a new stretchable, transparent conductor that can be folded or stretched and released, resulting in a large curvature or a significant strain, at least 10,000 times without showing signs of fatigue.
This is a crucial step in creating a new generation of foldable electronics-think a flat-screen television that can be rolled up for easy portability-and implantable medical devices.
The work, published Monday in the Proceedings of the National Academy of Sciences, pairs gold nanomesh with a stretchable substrate made with polydimethylsiloxane, or PDMS.
The substrate is stretched before the gold nanomesh is placed on it-a process known as"prestretching "-and the material showed no sign of fatigue
The gold nanomesh also proved conducive to cell growth, indicating it is a good material for implantable medical devices.
Fatigue is a common problem for researchers trying to develop a flexible, transparent conductor, making many materials that have good electrical conductivity,
flexibility and transparency-all three are needed for foldable electronics-wear out too quickly to be said practical
Zhifeng Ren, a physicist at the University of Houston and principal investigator at the Texas Center for Superconductivity,
who was the lead author for the paper. The new material, produced by grain boundary lithography,
In materials science,"fatigue"is used to describe the structural damage to a material caused by repeated movement or pressure, known as"strain cycling."
That means the materials aren't durable enough for consumer electronics or biomedical devices.""Metallic materials often exhibit high cycle fatigue,
and fatigue has been a deadly disease for metals, "the researchers wrote.""We weaken the constraint of the substrate by making the interface between the Au (gold) nanomesh and PDMS slippery,
and expect the Au nanomesh to achieve superstretchability and high fatigue resistance, "they wrote in the paper."
"Free of fatigue here means that both the structure and the resistance do not change or have little change after many strain cycles."
"the Au nanomesh does not exhibit strain fatigue when it is stretched to 50 percent for 10,000 cycles."
The researchers used mouse embryonic fibroblast cells to determine biocompatibility; that, along with the fact that the stretchability of gold nanomesh on a slippery substrate resembles the bioenvironment of tissue
or organ surfaces, suggest the nanomesh"might be implanted in the body as a pacemaker electrode,
a connection to nerve endings or the central nervous system, a beating heart, and so on, "they wrote. Ren's lab reported the mechanics of making a new transparent and stretchable electric material,
using gold nanomesh, in a paper published in Nature Communications in January 2014. This work expands on that,
producing the material in a different way to allow it to remain fatigue-free through thousands of cycles s
#Stanford engineers invent transparent coating that cools solar cells to boost efficiency: The quandary: The hotter solar cells get,
the less efficiently they convert sunlight to electricity; The fix: A new transparent overlay allows light to hit the cells
while shunting heat away Now three Stanford engineers have developed a technology that improves on solar panel performance by exploiting this basic phenomenon.
Their invention shunts away the heat generated by a solar cell under sunlight and cools it in a way that allows it to convert more photons into electricity.
The work by Shanhui Fan, a professor of electrical engineering at Stanford, research associate Aaswath P. Raman and doctoral candidate Linxiao Zhu is described in the current issue of Proceedings of the National Academy
of Sciences. The group's discovery tested on a Stanford rooftop, addresses a problem that has bedeviled long the solar industry:
The hotter solar cells get, the less efficient they become at converting the photons in light into useful electricity.
The Stanford solution is based on a thin, patterned silica material laid on top of a traditional solar cell.
The material is transparent to the visible sunlight that powers solar cells, but captures and emits thermal radiation,
or heat, from infrared rays.""Solar arrays must face the sun to function, even though that heat is detrimental to efficiency,
"Fan said.""Our thermal overlay allows sunlight to pass through, preserving or even enhancing sunlight absorption,
but it also cools the cell by radiating the heat out and improving the cell efficiency."
"A cool way to improve solar efficiency In 2014, the same trio of inventors developed an ultrathin material that radiated infrared heat directly back toward space without warming the atmosphere.
They presented that work in Nature, describing it as"radiative cooling "because it shunted thermal energy directly into the deep, cold void of space.
In their new paper, the researchers applied that work to improve solar array performance when the sun is beating down.
The Stanford team tested their technology on a custom-made solar absorber-a device that mimics the properties of a solar cell without producing electricity-covered with a micron-scale pattern designed to maximize the capability to dump heat
Their experiments showed that the overlay allowed visible light to pass through to the solar cells, but that it also cooled the underlying absorber by as much as 55 degrees Fahrenheit.
For a typical crystalline silicon solar cell with an efficiency of 20 percent, 55 F of cooling would improve absolute cell efficiency by over 1 percent,
a figure that represents a significant gain in energy production. The researchers said the new transparent thermal overlays work best in dry, clear environments,
which are preferred also sites for large solar arrays. They believe they can scale things up so commercial and industrial applications are feasible
perhaps using nanoprint lithography, which is a common technique for producing nanometer scale patterns.""That's not necessarily the only way,"said Raman, a co-first-author of the paper."
"New techniques and machines for manufacturing these kinds of patterns will continue to advance. I'm optimistic."
"Cooler cars Zhu said the technology has significant potential for any outdoor device or system that demands cooling
"Say you have a car that is bright red, "Zhu said.""You really like that color,
but you'd also like to take advantage of anything that could aid in cooling your vehicle during hot days.
which uses nanopores to read individual nucleotides, paves the way for better-and cheaper-DNA sequencing.
One of the most critical biological and medical tools available today, it lies at the core of genome analysis. Reading the exact make-up of genes,
scientists can detect mutations, or even identify different organisms. A powerful DNA sequencing method uses tiny
However,"nanopore sequencing"is prone to high inaccuracy because DNA usually passes through very fast. EPFL scientists have discovered now a viscous liquid that slows down the process up to a thousand times,
The breakthrough is published in Nature Nanotechnology. Reading too fast DNA is a long molecule made up of four repeating different building-blocks.
"and are strung together in various combinations that contain the cell's genetic information, such as genes. Essentially
In nanopore sequencing, DNA passes through a tiny pore in a membrane, much like a thread goes through a needle.
Slowing things down The lab of Aleksandra Radenovic at EPFL's Institute of Bioengineering has now overcome the problem of speed by using a thick,
viscous liquid that slows the passage of DNA two to three orders of magnitude. As a result, sequencing accuracy improves down to single nucleotides.
The team then created a nanopore on membrane, almost 3 nm wide. The next step was to dissolve DNA in a thick liquid that contained charged ions and
Finally, the team tested their system by passing known nucleotides, dissolved in the liquid, through the nanopore multiple times.
Although still at a testing stage, the team is aiming to continue their work by testing entire DNA strands."
which is promising for sequencing with solid-state nanopores, "says Jiandong Feng. The scientists also predict that using high-end electronics
and control of the viscosity gradient of the liquid could further optimize the system. By combining ionic liquids with nanopores on molybdenum disulfide thin films, they hope to create a cheaper DNA sequencing platform with a better output.
The work offers an innovative way that can improve one of the best DNA sequencing methods available."
"In years to come, sequencing technology will definitely shift from research to clinics, "says Aleksandra Radenovic."
"For that, we need rapid and affordable DNA sequencing -and nanopore technology can deliver
#Pioneering research develops new way to capture light--for the computers of tomorrow Pioneering research by an international team of scientists,
including from the University of Exeter, has developed techniques that will allow the first memory chip that can capture light.
The key breakthrough will allow large quantities of data to be stored directly on an integrated optical chip,
rather than being processed and stored electronically, as happens today. Light is suited ideally to ultra-fast high-bandwidth data transfer,
and optical communications form an indispensable part of the IT world of today and tomorrow. However
a stumbling block so far has been the storage of large quantities of data directly on integrated chips in the optical domain.
While optical fibre cables-and with them, data transfer by means of light-have long since become part of our everyday life,
data on a computer are processed still and stored electronically. The team of scientists from Germany and England have made a key breakthrough by capturing light on an integrated chip,
so developing the first permanent, all-optical on-chip memory. The research is published in leading scientific journal, Nature Photonics.
Professor David Wright from the University of Exeter's Engineering department said:""With our prototype we have, for the first time,
a nanoscale integrated optical memory that could open up the route towards ultra-fast data processing and storage.
Our technology might also eventually be used to reproduce in computers the neural-type processing that is carried out by the human brain."
"Professor Wolfram Pernice, from the Institute of Physics at Mnster University and who led the work said:"
"The all-optical memory devices we have developed provide opportunities that go far beyond any of the approaches to optical data processing available today.""
""Optical bits can be written in our system at frequencies of up to a gigahertz or more,"adds Professor Harish Bhaskaran from Oxford university in England,
one of the lead co-authors, "and our approach can define a new speed limit for future processors,
by delivering extremely fast on-chip optical data storage"In addition, he says, "the written state is preserved
when the power is removed, unlike most current on-chip memories"."The scientists from Oxford, Exeter, Karlsruhe and Mnster used so-called phase change materials at heart of their all-optical memory.
The distinguishing feature of these materials is that they radically change their optical properties depending their phase state,
i e. depending on the arrangement of the atoms in the material. This changeability-between crystalline (regular) and amorphous (irregular) states-allowed the team to store many bits in a single integrated nanoscale optical phase-change cell l
#Molecular diagnostics at home: Chemists design rapid, simple, inexpensive tests using DNA: Electrochemical test's sensing principle may be generalized to many different targets,
leading to inexpensive devices that could detect dozens of disease markers in less than 5 minutes Chemists used DNA molecules to developed rapid,
inexpensive medical diagnostic tests that take only a few minutes to perform. Their findings, which will officially be published tomorrow in the Journal of the American Chemical Society,
may aid efforts to build point-of-care devices for quick medical diagnosis of various diseases ranging from cancer, allergies, autoimmune diseases, sexually transmitted diseases (STDS),
and many others. The new technology may also drastically impact global health due to its low cost and easiness of use, according to the research team.
The rapid and easy-to-use diagnostic tests are made of DNA and use one of the simplest force in chemistry,
when atoms are brought too close together-to detect a wide array of protein markers that are linked to various diseases.
The design was created by the research group of Alexis Vallée-Bélisle, a professor in the Department of chemistry at University of Montreal."
and the results sent back to the doctor's office. If we can move testing to the point of care,
which would enhance the effectiveness of medical interventions. The key breakthrough underlying this new technology came by chance."
(or traffic) at the surface of a sensor, which drastically reduced the signal of our tests,
"said Sahar Mashid, postdoctoral scholar at the University of Montreal and first author of the study."
and limits the ability of this DNA to hybridize to its complementary strand located on the surface of a gold electrode.
Francesco Ricci, a professor at University of Rome Tor Vergata who also participated in this study,
explains that this novel signaling mechanism produces sufficient change in current to be measured using inexpensive electronics similar to those in the home glucose test meter used by diabetics to check their blood sugar.
allowing us to build inexpensive devices that could detect dozens of disease markers in less than five minutes in the doctor's office
including pathogen detection in food or water and therapeutic drug monitoring at home, a feature which could drastically improve the efficient of various class of drugs and treatments a
#Efforts to Improve Properties of Body Implants Using Nanocoatings Yield Positive Results Despite the high performance of metallic implants, including titanium and its alloys, in human body,
the relatively weak corrosion resistance of the implants in the body and their inappropriate compatibility has resulted in a great challenge in the application of metallic alloys.
Therefore, Iranian researchers studied a type of composite nanocoating to obtain modified properties of biomaterials to be used in human body.
The nanocoating has high resistance to abrasion and corrosion. A nanocomposite coating has been produced in this research by combining hydroxyapatite nanoparticles as the base material and diopside ceramic.
The nanocomposite has desirable mechanical properties biocompatibility, chemical stability and resistance to corrosion and abrasion.
This research tries to use a simple but cost-effective method to produce laboratorial samples.
The method is able to produce surface coatings with very low roughness, excellent resistance to corrosion and abrasion,
and to produce surfaces without cracks during the coating process. According to the researchers, when the amount of diopside added to the base of hydroxyapatite increases up to 30 weight percent, the size of final composite grain and its size distribution significantly decreases after two steps of sintering process.
This fact is important because the optimum conditions for applying nanocomposite coating through electrophoretic method on metals are obtained at low particle size distributions s
#A new single-molecule tool to observe enzymes at work A team of scientists at the University of Washington
and the biotechnology company Illumina have created an innovative tool to directly detect the delicate, single-molecule interactions between DNA and enzymatic proteins.
Their approach provides a new platform to view and record these nanoscale interactions in real time. As they report Sept. 28 in Nature Biotechnology,
this tool should provide fast and reliable characterization of the different mechanisms cellular proteins use to bind to DNA strands--information that could shed new light on the atomic-scale interactions within our cells
and help design new drug therapies against pathogens by targeting enzymes that interact with DNA."
"There are other single-molecule tools around, but our new tool is said far more sensitive senior author and UW physics professor Jens Gundlach."
"We can really pick up atomic-scale movements that a protein imparts onto DNA.""As can happen in the scientific process,
they developed this tool--the single-molecule picometer-resolution nanopore tweezers, or SPRNT--while working on a related project.
The UW team has been exploring nanopore technology to read DNA sequences quickly. Our genes are long stretches of DNA molecules,
"In their approach, Gundlach and his team measure an electrical current through a biological pore called Mspa,
Gundlach and his team, in the process of investigating nanopore sequencing, tried out a variety of molecular motors to move DNA through the pore.
Biologists have recognized long that proteins have different structures to perform these roles, but the physical motion of proteins as they work on DNA has been difficult to detect directly."
Gundlach and his team show that SPRNT is sensitive enough to differentiate between the mechanisms that two cellular proteins use to pass DNA through the nanopore opening.
according to co-author and UW physics doctoral student Jonathan Craig. They even discovered that these two steps involve sequential chemical processes that the protein uses to walk along DNA."
and that has a ton of implications--from understanding how life works to drug design,
Gundlach believes this tool may open a new window for understanding how cellular proteins process DNA,
These fine details may also help scientists understand how mutations in proteins can lead to disease
or find protein properties that would be ideal targets for drug therapies.""For example, viral genes code for their own proteins that process their DNA,
"If we can use SPRNT to screen for drugs that specifically disrupt the functioning of these proteins,
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