#Permanent data storage with light The first all-optical permanent on-chip memory has been developed by scientists of Karlsruhe Institute of technology (KIT) and the universities of Münster, Oxford, and Exeter.
This is an important step on the way towards optical computers. Phase change materials that change their optical properties depending on the arrangement of the atoms allow for the storage of several bits in a single cell.
With optical elements, computers can work more rapidly and more efficiently. Optical fibers have long since been used for the transmission of data with light.
But on a computer, data are processed still and stored electronically. Electronic exchange of data between processors and the memory limits the speed of modern computers.
To overcome this so-called Von neumann bottleneck, it is not sufficient to optically connect memory and processor,
as the optical signals have to be converted into electric signals again. Scientists, hence, look for methods to carry out calculations and data storage in a purely optical manner.
Scientists of KIT the University of Münster, Oxford university, and Exeter University have developed now the first all-optical, nonvolatile on-chip memory."
"Optical bits can be written at frequencies of up to a gigahertz. This allows for extremely quick data storage by our all-photonic memory,
"Professor Wolfram Pernice explains. Pernice headed a working group of the KIT Institute of Nanotechnology (INT)
and recently moved to the University of Münster.""The memory is compatible not only with conventional optical fiber data transmission,
but also with latest processors,"Professor Harish Bhaskaran of Oxford university adds. The new memory can store data for decades even
when the power is removed. Its capacity to store many bits in a single cell of a billionth of a meter in size (multilevel memory) also is highly attractive.
Instead of the usual information values of 0 and 1, several states can be stored in an element
and even autonomous calculations can be made. This is due to so-called phase change materials novel materials that change their optical properties depending on the arrangement of the atoms:
Within shortest periods of time, they can change between crystalline (regular) and amorphous (irregular) states.
For the memory, the scientists used the phase change material Ge2sb2te5 (GST. The change from crystalline to amorphous (storing data) and from amorphous to crystalline (erasing data) is initiated by ultrashort light pulses.
For reading out the data, weak light pulses are used. Permanent all-optical on-chip memories might considerably increase future performance of computers
and reduce their energy consumption. Together with all-optical connections, they might reduce latencies. Energy-intensive conversion of optical signals into electronic signals and vice versa would no longer be required i
#Quantum teleportation: World record of 100 kilometers Researchers at the National Institute of Standards and Technology (NIST) have teleported
"or transferred quantum information carried in light particles over 100 kilometers (km) of optical fiber, four times farther than the previous record.
The experiment confirmed that quantum communication is feasible over long distances in fiber. Other research groups have teleported quantum information over longer distances in free space,
but the ability to do so over conventional fiber-optic lines offers more flexibility for network design.
Not to be confused with Star trek's fictional"beaming up"of people, quantum teleportation involves the transfer,
or remote reconstruction, of information encoded in quantum states of matter or light. Teleportation is useful in both quantum communications and quantum computing,
Arraythe lead author, Hiroki Takesue, was a NIST guest researcher from NTT Corp. in Japan.
The achievement was made possible by advanced single-photon detectors designed and made at NIST.""Only about 1 percent of photons make it all the way through 100 km of fiber,
"NIST's Marty Stevens says.""We never could have done this experiment without these new detectors,
which can measure this incredibly weak signal.""Until now, so much quantum data was lost in fiber that transmission rates
and distances were low. The new NTT/NIST teleportation technique could be used to make devices called quantum repeaters that could resend data periodically
in order to extend network reach, perhaps enough to eventually build a"quantum internet.""Previously, researchers thought quantum repeaters might need to rely on atoms or other matter, instead of light,
a difficult engineering challenge that would also slow down transmission. Various quantum states can be used to carry information;
the NTT/NIST experiment used quantum states that indicate when in a sequence of time slots a single photon arrives.
The teleportation method is novel in that four of NIST's photon detectors were positioned to filter out specific quantum states.
The detectors rely on superconducting nanowires made of molybdenum silicide. They can record more than 80 percent of arriving photons,
The experiments were performed at wavelengths commonly used in telecommunications. Because the experiment filtered out and focused on a limited combination of quantum states
Thanks to the efficient detectors, researchers successfully teleported the desired quantum state in 83 percent of the maximum possible successful transmissions, on average.
#Highly flexible and wearable tactile sensor for robotics, electronics and healthcare applications A team of scientists from the National University of Singapore (NUS) Faculty of engineering has developed a wearable liquid-based microfluidic tactile
sensor that is small, thin, highly flexible and durable. Simple and cost-effective to produce, this novel device is very suitable for applications such as soft robotics, wearable consumer electronics, smart medical prosthetic devices,
as well as real-time healthcare monitoring. Tactile sensors are data acquisition devices that detect and measure a diversity of properties arising from physical interaction
and translate the information acquired to be analysed by an interconnected intelligent system. Conventional tactile sensors that are available today are typically rigid and in solid-state form
restricting various natural body movements when used and may also be subjected to plastic deformation and failure when pressure is exerted,
Addressing the limitations of existing tactile sensors, a team of researchers led by Professor Lim Chwee Teck from NUS'Department of Biomedical engineering achieves a significant technological breakthrough by adopting a liquid-based pressure sensing method in the design of such sensors.
Novel liquid-based pressure sensing element The newly developed microfluidic tactile sensor is fabricated on a flexible substrate like silicone rubber,
and uses non-corrosive, nontoxic 2d nanomaterial suspension in liquid form, such as graphene oxide, as the pressure sensing element to recognise force-induced changes.
The NUS team has put the device through rigorous tests and also subjected it to various strenuous deformations, such as pressing, bending or stretching,
such as running a car tyre over it, the electrical output was uniformed highly and there was no damage to the functionality of the device.
From idea to market The team's invention will further advance the applications of tactile sensors
which are utilised already increasingly for monitoring critical parameters in biomedical applications, especially for those that may come in contact with human skin
"This liquid-based microfluidic tactile sensor, which is the first of its kind, addresses an existing gap in the market.
the sensor gives a better fit when monitoring natural body movements. Its small size, durability and ease of production further differentiate this novel device from conventional tactile sensors.
With the rapid advancement of healthcare and biomedical technologies as well as consumer electronics, we are optimistic about new possibilities to commercialise our invention,
"said Prof Lim. The NUS team has filed already a patent for its creation and is also keen to explore licensing partnerships in commercial development.
#Antimicrobial film for future implants The implantation of medical devices is not without risks. Bacterial or fungal infections can occur
and the body's strong immune response may lead to the rejection of the implant. Researchers at Unit 1121"Biomaterials and Bioengineering"(Inserm/Strasbourg university) have succeeded in creating a biofilm with antimicrobial, antifungal and anti-inflammatory properties.
It may be used to cover titanium implants (orthopaedic prostheses, pacemakers...prevent or control postoperative infections. Other frequently used medical devices that cause numerous infectious problems, such as catheters, may also benefit.
These results are published in the journal Advanced Healthcare Materials. Implantable medical devices (prosthesis/pacemakers) are an ideal interface for microorganisms,
which can easily colonize their surface. As such, bacterial infection may occur and lead to an inflammatory reaction.
This may cause the implant to be rejected. These infections are caused mainly by bacteria such as Staphylococcus aureus,
originating in the body, and Pseudomonas aeruginosa. These infections may also be caused fungal or by yeasts.
The challenge presented by implanting medical devices in the body is preventing the occurrence of these infections
which lead to an immune response that compromises the success of the implant. Antibiotics are used currently during surgery
or to coat certain implants. However, the emergence of multi-resistant bacteria now restricts their effectiveness.
A biofilm invisible to the naked eye It is within this context that researchers at the"Bioengineering
and Biomaterials"Unit 1121 (Inserm/Strasbourg University) with four laboratories1 have developed a biofilm with antimicrobial and anti-inflammatory properties.
Researchers have used a combination of two substances: polyarginine (PAR) and hyaluronic acid (HA), to develop and create a film invisible to the naked eye (between 400 and 600 nm thick) that is made of several layers.
As arginine is metabolised by immune cells to fight pathogens, it has been used to communicate with the immune system to obtain the desired anti-inflammatory effect.
Hyaluronic acid, a natural component of the body, was chosen also for its biocompatibility and inhibiting effect on bacterial growth.
Embedded antimicrobial peptides on a thin silver coating The film is also unique due to the fact that it embeds natural antimicrobial peptides
in particular catestatin, to prevent possible infection around the implant. This is an alternative to the antibiotics that are used currently.
As well as having a significant antimicrobial role, these peptides are not toxic to the body that they are secreted into.
They are capable of killing bacteria by creating holes in their cellular wall and preventing any counterattack on their side.
In this study researchers show that poly (arginine), associated with hyaluronic acid, possesses microbial activity against Staphylococcus aureus (S. aureus) for over 24 hours."
"In order to prolong this activity, we have placed a silver-coated precursor before applying the film. Silver is an anti-infectious material currently used on catheters and dressings.
This strategy allows us to extend antimicrobial activity in the long term"explains Philippe Lavalle, Research director at Inserm.
Effectively reduces inflammation, preventing and controlling infection The results from numerous tests performed on this new film shows that it reduces inflammation
and prevents the most common bacterial and fungal infections. On the one hand, researchers demonstrate, through contact with human blood,
that the presence of the film on the implant suppresses the activation of inflammatory markers normally produced by immune cells in response to the implant.
Moreover""the film inhibits the growth and long-term proliferation of staphylococcal bacteria (Staphylococcus aureus), yeast strains (Candida albicans) or fungi (Aspegillus fumigatus) that frequently cause implant-related infection"emphasises Philippe Lavalle.
Researchers conclude that this film may be used in vivo on implants or medical devices within a few years to control the complex microenvironment surrounding implants
and to protect the body from infection n
#Physiologists uncover a new code at the heart of biology UT Southwestern physiologists trying to understand the genetic code have found a previously unknown code that helps explain which protein should be created to form a particular type of cell.
The human body is made up of tens of trillions of cells. Each cell contains thousands of proteins,
which determine how the cell should form and what functions it needs to perform. Proteins, in turn, are made up of hundreds of amino acids.
The blueprint for each protein is specified by genetic codons, which are triplets of nucleotides that can make 20 different types of amino acids.
The way in which amino acids are linked together then determines which proteins are produced eventually, and in turn,
"Our results uncovered a new'code'within the genetic code. We feel this is quite important, as the finding uncovers an important regulatory process that impacts all biology,
"said Dr. Yi Liu, Professor of Physiology. It was known long that almost every amino acid can be encoded by multiple synonymous codons and that every organism,
from humans to fungi, has a preference for certain codons. The researchers found that more frequently used codons?
"The genetic code of nucleic acids is central to life, as it specifies the amino acid sequences of proteins,
"said Dr. Liu, the Louise W. Kahn Scholar in Biomedical Research.""By influencing the speed with
which a protein is assembled from amino acid building blocks, the use of"fast"and"slow"codons can affect protein folding,
This speed control mechanism makes sure that proteins are assembled and folded properly in different cells. Therefore, the genetic code not only specifies the sequence of amino acids but also the shape of the protein."
"The researchers found that proteins with identical amino acid sequences can have different functions if they are assembled at different speeds.
This can have important implications for identifying human disease-causing mutations because this study indicates that a mutation does not have to change amino acid identity to cause a disease.
In fact, most mutations in human DNA do not result in amino acid change.""Therefore, our study indicates that the new"code"--the speed limit of assembly--within the genetic code can dictate the ultimate function of a given protein,
"said Dr. Liu u
#Metastatic breast cancer cells turn on stem cell genes It only takes seconds: one cancerous cell breaks off from a tumor, slips into the bloodstream and quickly lodges elsewhere in the body.
These colonizers may bloom into deadly metastatic cancer right away or lie dormant for years, only to trigger a recurrence decades after the primary tumor is removed.
Metastases cause the vast majority of cancer deaths, but their tiny seeds are so difficult to track that few researchers have managed to study them.
Now, scientists from UC San francisco describe capturing and studying individual metastatic cells from human breast cancer tumors implanted into mice as the cells escaped into the blood stream
and began to form tumors elsewhere in the body. The researchers discovered that genetic programs expressed in these cells were quite distinct from the primary tumors in
which they originated and included genes typically expressed in mammary stem cells. The findings, published online Sept. 23,2015 in Nature, could change the way researchers think about how cancer spreads
and suggest new drugs to track down and disable its deadly seeds. For the most part, modern cancer drugs ignore differences between primary
and metastatic tumors, said Zena Werb, Phd, professor and vice-chair of anatomy at UCSF, and a senior author on the new study."
"We test drugs for their ability to make primary tumors shrink, but most just don't work on metastases,
and this leaves patients open to recurrence,"Werb said.""Patients have their original tumor treated or removed,
but then the cancer comes back 20,30, 40 years later because there were just a few metastatic cells sitting around."
"Catching metastatic cancer cells in the act No one really knows how dormant metastatic cells can survive incognito for decades,
said Devon Lawson, Phd, who led the research team as a UCSF postdoctoral researcher and is now an assistant professor of physiology and biophysics at UC Irvine."
"It's a big black box in the cancer field--mostly because it's very difficult to study,
"she said. As a result, Lawson said, only about 7 percent of all breast cancer funding goes to studying metastatic cancer,
despite the fact that it causes virtually all breast cancer deaths. Previous work by Werb's group had found a subset of cells at the edges of breast cancer tumors that seemed primed to metastasize.
Their close contact with the bloodstream and with proteins in the surrounding tumor microenvironment seemed to turn on genetic programs akin to those of mammary stem cells--the cells that allow breasts to form during puberty
and grow during lactation. These genes for self-replication could make these cells particularly apt to generate new tumors elsewhere in the body.
But the researchers had yet to catch the cells in the act. In the new paper, the researchers used a technique called patient derived xenograft (PDX),
which involves transplanting human tumor cells into mice. Against the backdrop of healthy mouse tissue, rogue metastatic cells from the human tumor stick out like flares.
The researchers developed a new method using flow cytometry that let them capture individual human metastatic cancer cells traveling through the mouse's blood
or lodged elsewhere in its body, then used newly-developed microfluidic technology to characterize the active genes in these rare cells."
"We were able to look at gene expression at a whole new level of resolution, "Lawson said."
"We could pull 12 metastatic cells out of the brain and tell you what is special about those 12 cells.
Or the two cells we found in the blood. And we discovered there's something really unique about metastatic cells as they arrive in distant tissues."
"Metastases show stem cell qualities The team compared patterns of gene expression in human cancer cells lodged in different organs of the PDX mice and found stark differences between early-stage and more advanced metastatic colonies.
In metastases that had grown already and spread throughout an organ, the cancer cells'gene activity looked much like that of the primary tumor that had been transplanted into the mice,
though with subtly different features specific to the new organ, whether lymph, liver, lung or brain.
In contrast, early-stage metastases and cancer cells traveling through the blood expressed genes typically active in mammary stem cells and quite distinct from primary tumor cells.
which the researchers surmised might help metastatic colonies survive in new and hostile environments. Remarkably, the same signature pattern of gene activity was found in metastatic cells in mice whose tumors came from genetically and clinically diverse human patients.
In other words, the genetic program that makes a cell metastatic did not depend on the genetics of its tumor of origin--suggesting that new techniques might allow researchers to find
and specifically target these cells throughout the body in a variety of patient populations. Insights could lead to targeted therapies The research team performed a proof of principle experiment to demonstrate how valuable information about metastatic gene expression could be for drug development.
Since metastatic cells that were beginning to differentiate into secondary tumors showed high expression of genes cmyc and CDK2, the researchers treated 24 PDX mice with dinaciclib,
a CDK inhibiting drug known to kill off cells with high MYC levels. Whereas 44 percent of control mice (11 of 25) developed secondary tumors within four weeks, researchers could only find metastatic cells in one drug-treated mouse (4 percent.
Werb emphasized that this test was just a proof of principal and that dinaciclib itself may
was that the drug managed to nearly eliminate metastases without shrinking the primary tumor.""If this drug had only been tested on primary tumors,
we would have said it doesn't work, "she said.""This tells us you actually have to look at metastases
if you want drugs that treat them.""Preventing metastatic cells from invading other parts of the body has been a priority for cancer researchers for many years,
said Andrei Goga, MD, Phd, professor of cell and tissue biology, and of medicine at UCSF and a co-corresponding author on the new study."
"But practically speaking, by the time you've detected the tumor, that horse is either already out of the barn
or it isn't. This new study is exciting because if you know the genetics of these early metastatic cells you can go after them specifically,
wherever they are in the body. And that's the name of the game.""The researchers say the single-cell genomics they used in this study
--which a consortium of researchers at UCSF are applying to diverse biological and clinical questions--could have a major impact on the emerging field of precision medicine."
"It's definitely a brave new world, "Lawson said.""We couldn't have done this even five years ago.
By tweaking the genomes of these viruses, known as bacteriophages, researchers hope to customize them to target any type of pathogenic bacteria.
MIT biological engineers have devised a new mix-and-match system to genetically engineer viruses that target specific bacteria.
This approach could generate new weapons against bacteria for which there are no effective antibiotics, says Timothy Lu, an associate professor of electrical engineering and computer science and biological engineering."
"These bacteriophages are designed in a way that's relatively modular. You can take genes and swap them in and out and get a functional phage that has new properties,
the senior author of a paper describing this work in the Sept. 23 edition of the journal Cell Systems.
and while many of these are beneficial, some can cause disease. For example some reports have linked Crohn's disease to the presence of certain strains of E coli."
"We'd like to be able to remove specific members of the bacterial population and see what their function is in the microbiome,
but more information about the microbiome is needed to effectively design such therapies.""The paper's lead author is Hiroki Ando, an MIT research scientist.
Other authors are MIT research scientist Sebastien Lemire and Diana Pires, a research fellow at the University of Minho in Portugal.
but efforts to harness them for medical use have been hampered because isolating useful phages from soil
Also, each family of bacteriophages can have a different genome organization and life cycle, making it difficult to engineer them
By swapping in different genes for the tail fiber, they generated phages that target several types of bacteria."
the researchers combed through databases of phage genomes looking for sequences that appear to code for the key tail fiber section, known as gp17.
they had to create a new system for performing the genetic engineering. Existing techniques for editing viral genomes are fairly laborious,
so the researchers came up with an efficient approach in which they insert the phage genome into a yeast cell,
where it exists as an"artificial chromosome"separate from the yeast cell's own genome.
During this process the researchers can easily swap genes in and out of the phage genome."
"Once we had that method, it allowed us very easily to identify the genes that code for the tails
so that simplifies that workflow in the lab."A targeted strike In this study, the researchers engineered phages that can target pathogenic Yersinia and Klebsiella bacteria,
and gastrointestinal infections, including pneumonia, sepsis, gastritis, and Legionnaires'disease. One advantage of the engineered phages is that unlike many antibiotics,
they are very specific in their targets.""Antibiotics can kill off a lot of the good flora in your gut,
"We aim to create effective and narrow-spectrum methods for targeting pathogens.""Lu and his colleagues are now designing phages that can target other strains of harmful bacteria,
which could have applications such as spraying on crops or disinfecting food, as well as treating human disease.
Another advantage of this approach is that all of the phages are based on an identical genetic scaffold,
-and-answer experiment Researchers used a brain-to-brain interface they developed to allow pairs of participants to play a'20 question'style game by transmitting signals from one brain to another over the Internet.
"said lead author Andrea Stocco, an assistant professor of psychology and a researcher at UW's Institute for Learning & Brain sciences."
Here's how it works: The first participant, or"respondent,"wears a cap connected to an electroencephalography (EEG) machine that records electrical brain activity.
The respondent is shown an object (for example, a dog) on a computer screen, and the second participant,
or"inquirer,"sees a list of possible objects and associated questions. With the click of a mouse, the inquirer sends a question
and the respondent answers"yes"or"no"by focusing on one of two flashing LED LIGHTS attached to the monitor,
which flash at different frequencies. A"no"or"yes"answer both send a signal to the inquirer via the Internet
and activate a magnetic coil positioned behind the inquirer's head. But only a"yes"answer generates a response intense enough to stimulate the visual cortex
and cause the inquirer to see a flash of light known as a"phosphene.""The phosphene--which might look like a blob,
The experiment was carried out in dark rooms in two UW labs located almost a mile apart and involved five pairs of participants,
added a plastic spacer undetectable to the participant that weakened the magnetic field enough to prevent the generation of phosphenes.
"said co-author Chantel Prat, a faculty member at the Institute for Learning & Brain sciences and a UW associate professor of psychology."
or by the brain signal transmission being interrupted by hardware problems.""While the flashing lights are signals that we're putting into the brain,
and transmitted brain signals from a human to a rat, using electrodes inserted into animals'brains.
In the 2013 experiment, the UW team used noninvasive technology to send a person's brain signals over the Internet to control the hand motions of another person.
The first experiment evolved out of research by co-author Rajesh Rao, a UW professor of computer science and engineering,
on brain-computer interfaces that enable people to activate devices with their minds. In 2011, Rao began collaborating with Stocco
or simply to transfer knowledge from teacher to pupil. The team is also working on transmitting brain states--for example,
or from a focused student to one who has attention deficit hyperactivity disorder, or ADHD."
"Imagine having someone with ADHD and a neurotypical student, "Prat said.""When the non-ADHD student is paying attention,
the ADHD student's brain gets put into a state of greater attention automatically.""Many technological advancements over the past century, from the telegraph to the Internet, were created to facilitate communication between people.
The UW team's work takes a different approach, using technology to strip away the need for such intermediaries."
"Evolution has spent a colossal amount of time to find ways for us and other animals to take information out of our brains
and communicate it to other animals in the forms of behavior, speech and so on, "Stocco said."
Other co-authors are UW computer science and neurobiology undergraduate student Darby Losey, UW bioengineering doctoral student Jeneva Cronin, UW bioengineering doctoral student Joseph Wu,
and Justin Abernethy, a research assistant at the UW Institute for Learning & Brain sciences s
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