Integrated iWheelchair system

The Hong Kong Polytechnic University (PolyU) has developed an intelligent system called "iWheelchair," integrating a series of advanced PolyU technologies from its Interdisciplinary Division of Biomedical Engineering (BME) and Institute of Textiles and Clothing (ITC).

With a tablet computer as the centralized operation platform, the system integrates a variety of functions such as environment control, as well as safety, health and hygiene monitoring with automated alert, which better caters for the needs of users and reduce the workload of their caregivers. This wheelchair is unique in integrating the above functions into one platform in the market.

By providing simple touchscreen commands on the tablet, users can control any home devices connected to the system, such as electric curtains, TV, motorized projector screens and electric beds. For those with impairment of hand functions, a fabric electronic switch can be used to convert thumb movements into touchscreen commands. Moreover, a sensor attached to the wheelchair measures vital health signals such as heart rate, and feed the readings into the computer for instant display and future record, while the fall monitoring function can activate an alarm through the tablet when the user or the wheelchair falls. The diaper wrap and the cushion seat is made with nano-treated fabric with dirt-proof, water repellent and antibacterial features, and the latter has fabric sensors that monitor the user's posture and buzz the user for prolonged inactivity to avoid bedsores and other circulatory conditions. The system is even connected to a smart diaper with sensors that can detect moisture levels and activate the buzzer on the tablet when changing is needed. Finally, optional setting is available for sending out SMS and/or email alerts to designated caregivers or family members in case of a fall, prolonged inactivity, abnormal heart rate and wet diaper to enlist help.

The system uses Bluetooth for communication among all sensors. For sending out email or SMS alerts, a Wi-Fi connection or mobile data will be called for. In addition, the system can be easily customized to cater for the needs of individual users. The interdisciplinary project is supported by the Innovation and Technology Fund, and has won a bronze medal in the Seoul International Invention Fair 2015.

A demo system of iWheelchair has been installed at Jockey Club Activity Center of Hong Kong Federation of Handicapped Youth (HKFHY) for their members' trial. The research team will continue to work closely with HKFHY to enable iWheelchair to better cope with the everyday challenges faced by wheelchair users. "As a next step," said Ir Dr Eric W.C. Tam, Assistant Professor of BME and the Project Coordinator of iWheelchair, "we will explore collaboration opportunities with industry, integrate more functions in the iWheelchair, so that the technology can benefit more wheelchair users in our community."

Laser reveals water's secret life in soil

Hirmas uses his MLT scanner at night in a soil pit. Ambient daylight interferes with the detection of the pores. Cooler night temperatures also allow the scanner to stay cool and minimize the evaporation of water from the surface during the scanning procedure.

Most of us think nothing of rainfall or where it goes, unless it leads to flooding or landslides. But soil scientists have been studying how water moves across or through soil for decades. Daniel Hirmas, a professor at University of Kansas, and his team may be taking the study of soil hydrology to some exciting new territory. Territory that may help soil scientists manage water resources better.

Why is Hirmas trying to predict water movement in soil?

"There are a number of reasons why more accurate predictions of water flow is important. Better management of water resources is one," Hirmas says.

The flow of water in agriculture gives rise to many questions: Can we correctly predicting recharge rates of our aquifers in drought regions? Perhaps we can more efficiently use water for food production or predict how areas will react to climate change. Also, we could have better prediction of water runoff and soil erosion, deposition, and sedimentation of surface water reservoirs. Finally, we could predict how plant nutrients are transported in the soil environment.

Soil is made up of particles of sand, silt, and clay. Also within the soil is organic matter -- decomposed plant litter, soil microbes, other organisms, and root systems. Air and water make up the rest.

Hirmas has been researching the ease of water movement through soil, called conductivity. This happens in larger empty spaces, macropores, that help move water through the soil.

"The soil structure affects how easily water can be transported through the soil. This is called 'hydraulic conductivity'," says Hirmas. "Conductivity is a property of the soil. It affects how quickly water can be transported through the soil. Saturated hydraulic conductivity refers to the conductivity of the soil when the soil is fully saturated with water. In this case, all the soil pores are filled with water."

Soil pore size is important to conductivity because of some complex geometry and scientific properties. Simply, a soil pore that is twice as large as another will conduct sixteen times the volume of water as the smaller pore in the same amount of time.

Soil scientists call this movement of water preferential flow. Hirmas explains, "Preferential in this case means that a significant portion of the water will be transported through a relatively few number of large pores. That is, a few large pores preferentially transport a majority of the water."

Hirmas has been using a special tool called a multistripe laser triangulation (MLT) scanner. The scanner was originally developed for engineering purposes. Hirmas adapted its use to study soil pores and preferential flow.

To determine if the MLT scanner could be used to predict preferential flow, Hirmas designed a study. The research group took saturated soil and allowed blue dye to flow through the sample. An easily identifiable visible pattern developed. The areas of the soil that turned blue showed larger pores. These pores allowed the dyed water to pass through -- a preferential flow pattern. Next, they took the same soil sample, and scanned it using MLT. The pattern from the laser significantly matched that of the dye pattern.

The MLT offers advantages to researchers in the field of soil hydrology. "The MLT scanner is better at detecting and mapping the soil macroporosity when the soil is dry versus when it is saturated with water," Hirmas says. Using math to account for the difference between the two states of the soil, Hirmas can make predictions about water movement.

New world record in 5G wireless spectrum efficiency

Achieving 1.59Gbit/s over a 20MHz radio channel

Fiber optics (stock image). New research by engineers from the Universities of Bristol and Lund, working alongside National Instruments (NI), has demonstrated how a massive antenna system can offer a 12-fold increase in spectrum efficiency compared with current 4G cellular technology.

New research by engineers from the Universities of Bristol and Lund, working alongside National Instruments (NI), has demonstrated how a massive antenna system can offer a 12-fold increase in spectrum efficiency compared with current 4G cellular technology.

Multiple antenna technology, referred to as MIMO, is already used in many Wi-Fi routers and 4G cellular phone systems. Normally this involves up to four antennas at a base station. Using a flexible prototyping platform from NI based on LabVIEW system design software and PXI hardware, the Bristol configuration implements Massive MIMO, where 128 antennas are deployed at the base station.

The hardware behind this demonstration was provided to Bristol University as part of the Bristol Is Open programmable city infrastructure. Lund University has a similar setup, the LuMaMi testbed, enabling researchers at both sites to work in parallel with their development.

Bristol's Massive MIMO system used for the demo operates at a carrier frequency of 3.5GHz and supports simultaneous wireless connectivity to up to 12 single antenna clients. Each client shares a common 20MHz radio channel. Complex digital signal processing algorithms unravel the individual data streams in the space domain seen by the antenna array.

The Massive MIMO demonstration was conducted in the atrium of Bristol's Merchant Venturers Building and achieved an unprecedented bandwidth efficiency of 79.4bit/s/Hz. This equates to a sum rate throughput of 1.59Gbit/s in a 20MHz channel.

Professor Andrew Nix, Head of the CSN Group and Dean of Engineering, said: "This activity reinforces our well established propagation and system modelling work by offering a new capability in model validation for Massive MIMO architectures. This is a truly exciting time for our PhD students and opens up further opportunities for collaborative research with our national and international partners."

Ove Edfors, Professor of Radio Systems at Lund University says: "We see massive MIMO as the most promising 5G technology and we have pushed it forward together with partners in Bristol and in our EU project MAMMOET. It is a pleasure seeing those efforts materialize."

Mark Beach, Professor of Radio Systems Engineering in the Department of Electrical & Electronic Engineering and Manager of the EPSRC Centre for Doctoral Training (CDT) in Communications, added: "Massive MIMO is one of four core activities in '5G and beyond' wireless research at Bristol. This demonstration was made possible by the cohort training offered within our CDT in Communications. The CDT gives Bristol a unique edge to conduct activities at scale."

Fredrik Tufvesson, Professor with the Faculty of Engineering at Lund University explained: "It has been an exciting journey, hosting Bristol researchers Paul Harris and Siming Zhang as the group in Lund developed and tested the reference design. Our state-of-the-art test-beds show the culmination of significant effort from many researchers and it is fantastic to see these results from the Bristol deployment."

The collaborative research project with Lund University and National Instruments included five Bristol based PhD students under the collective guidance of five academic supervisors. In Lund seven PhD students and six supervisors contributed, making it a huge interdisciplinary research effort.

Paul Harris, PhD student in Bristol, explained: "My PhD training at Bristol alongside a two-month secondment at NI (Austin) put me in a unique position to use this cutting-edge equipment and support my fellow postgraduates with their state-of-the-art research in next generation wireless." Steffen Malkowsky, PhD student in Lund, continued: "Our joint secondment at NI led to a very close and fruitful collaboration that we have now brought back to Europe."

James Kimery, Director of RF Research and SDR Marketing at NI, commented: "With much discussion around 5G, NI is excited to work with top research institutions such as Bristol and Lund universities, and organizations like Bristol is Open to drive the standard forward. This Massive MIMO reference design system demonstrates the power and productivity researchers can achieve with NI tools and technologies."

Paul Wilson, Managing Director Bristol Is Open, remarked: "This is truly outstanding work putting Bristol at the forefront of 5G wireless connectivity. We are looking forward to moving this facility outdoors in late 2016 as part of the BIO Harbourside deployment."

Spectrum and power efficient wireless communications are core to Bristol University's Communication Systems & Networks (CSN) Group and the EPSRC Centre for Doctoral Training in Communications as well as to the department of Electrical and Information technology at Lund University.

Viktor Öwall, Dean of the Faculty of Engineering at Lund University, concluded: "Our openness, very similar goals, backgrounds and structures have enabled this remarkable achievement."

Biological mechanism passes on long-term epigenetic 'memories'

Researchers discover the on/off button for inheriting responses to environmental changes

A new study pinpoints the precise mechanism that turns the inheritance of environmental influences "on" and "off."

According to epigenetics -- the study of inheritable changes in gene expression not directly coded in our DNA -- our life experiences may be passed on to our children and our children's children. Studies on survivors of traumatic events have suggested that exposure to stress may indeed have lasting effects on subsequent generations. But how exactly are these genetic "memories" passed on?

A new Tel Aviv University study pinpoints the precise mechanism that turns the inheritance of environmental influences "on" and "off." The research, published last week in Cell and led by Dr. Oded Rechavi and his group from TAU's Faculty of Life Sciences and Sagol School of Neuroscience, reveals the rules that dictate which epigenetic responses will be inherited, and for how long.

"Until now, it has been assumed that a passive dilution or decay governs the inheritance of epigenetic responses," Dr. Rechavi said. "But we showed that there is an active process that regulates epigenetic inheritance down through generations."

Passing stress from one generation to the next

Researchers have been preoccupied with how the effects of stress, trauma, and other environmental exposures are passed from one generation to the next for years. Small RNA molecules -- short sequences of RNA that regulate the expression of genes -- are among the key factors involved in mediating this kind of inheritance. Dr. Rechavi and his team had previously identified a "small RNA inheritance" mechanism through which RNA molecules produced a response to the needs of specific cells and how they were regulated between generations.

"We previously showed that worms inherited small RNAs following the starvation and viral infections of their parents. These small RNAs helped prepare their offspring for similar hardships," Dr. Rechavi said. "We also identified a mechanism that amplified heritable small RNAs across generations, so the response was not diluted. We found that enzymes called RdRPs are required for re-creating new small RNAs to keep the response going in subsequent generations."

Most inheritable epigenetic responses in C.elegans worms were found to persist for only a few generations. This created the assumption that epigenetic effects simply "petered out" over time, through a process of dilution or decay.

"But this assumption ignored the possibility that this process doesn't simply die out but is regulated instead," said Dr. Rechavi, who in this study treated C.elegans worms with small RNAs that target the GFP (green fluorescent protein), a reporter gene commonly used in experiments. "By following heritable small RNAs that regulated GFP -- that 'silenced' its expression -- we revealed an active, tuneable inheritance mechanism that can be turned 'on' or 'off.'"

The scientists discovered that specific genes, which they named "MOTEK" (Modified Transgenerational Epigenetic Kinetics), were involved in turning on and off epigenetic transmissions.

"We discovered how to manipulate the transgenerational duration of epigenetic inheritance in worms by switching 'on' and 'off' the small RNAs that worms use to regulate genes," said Dr. Rechavi. "These switches are controlled by a feedback interaction between gene-regulating small RNAs, which are inheritable, and the MOTEK genes that are required to produce and transmit these small RNAs across generations.

"The feedback determines whether epigenetic memory will continue to the progeny or not, and how long each epigenetic response will last."

A comprehensive theory of heredity?

Although their research was conducted on worms, the team believes that understanding the principles that control the inheritance of epigenetic information is crucial for constructing a comprehensive theory of heredity for all organisms, humans included.

"We are now planning to study the MOTEK genes to know exactly how these genes affect the duration of epigenetic effects," said Leah Houri-Zeevi, a PhD student in Dr. Rechavi's lab and first author of the paper. "Moreover, we are planning to examine whether similar mechanisms exist in humans."

GOES-R satellite could provide better data for hurricane prediction

Penn State researchers found a better way to use satellite data in hurricane prediction models, which could revolutionize future hurricane predictions. Pictured is satellite imagery of Hurricane Karl, which was the focus of the researchers' proof-of-concept study.

The launch of the GOES-R geostationary satellite in October 2016 could herald a new era for predicting hurricanes, according to Penn State researchers. The wealth of information from this new satellite, at time and space scales not previously possible, combined with advanced statistical hurricane prediction models, could enable more accurate predictions in the future.

"For decades, geostationary satellites such as the GOES series have been the primary tool to monitor severe weather like storms and hurricanes in real time," said Fuqing Zhang, professor of meteorology and director of Penn State's Center for Advanced Data Assimilation and Predictability Techniques. "They have helped people see what's going on in the present, but, until now, we as a community have not been able to tap into these resources to guide us to predict future severe weather."

Geostationary satellites like the GOES series orbit the Earth at a fixed location, taking snapshots of cloud formations and other meteorological information. The National Oceanic and Atmospheric Administration operates GOES with contributions from NASA.

Historically, two main challenges exist when using satellite data for hurricane predictions -- the type and amount of data collected. Satellites do not directly measure many quantities related to a hurricane's intensity, such as surface pressure, wind speeds, temperature and water vapor beneath the cloudy regions of the hurricane eyewall. They do, however, collect data known as brightness temperature, which show how much radiation is emitted by objects on Earth and in the atmosphere at different infrared frequencies. Because all objects naturally emit and absorb different amounts of radiation at different frequencies, the complexity of data poses challenges to researchers hoping to use these data for hurricane prediction models.

"At some frequencies water vapor absorbs moderate amounts of radiation passing through it, at other frequencies it absorbs most of that radiation and at other frequencies it absorbs hardly any at all. Unlike water vapor, clouds strongly absorb radiation at all of these frequencies," said Eugene Clothiaux, professor of meteorology. "Comparing measurements at different frequencies leads to information about water vapor and clouds at different altitudes above the Earth. This begins to tell us about the physical structure of water vapor fields and clouds, including those in the area around a hurricane."

Using brightness temperature satellite data to improve model forecasts of hurricanes is not straightforward. Brightness temperature information is a complex mixture related to the ground, atmospheric water vapor and clouds. The team had to develop a sophisticated analysis and modeling scheme to extract information in useful ways for model forecasts.

Zhang, Masashi Minamide, graduate student in meteorology, and Clothiaux demonstrated in a pilot study that it is becoming feasible to use brightness data. They found definitive correlations between measurements of brightness temperature and information about the storm -- wind speed and sea level pressure underneath the hurricane. They report their results in the current issue of Geophysical Research Letters.

Using data from GOES-13, the team completed a proof-of-concept experiment, analyzing data from Hurricane Karl in 2010. They used the Penn State real-time hurricane analysis and prediction system that Zhang and his team have been developing and refining for nearly a decade.

"Hurricane prediction models work by chunking individual blocks of the hurricane and this starts from the initial information that is fed into the model," said Zhang. "We then run an ensemble of possible outcomes for the hurricane using different variables to estimate uncertainty and this tells us how the hurricane might behave. If we are able to use a higher resolution for the initial state, this could allow us to vastly improve hurricane predictions in the future."

GOES-13 provides data at a resolution of 2.5 miles, and GOES-R will increase that to under 0.6 miles for some frequencies of brightness temperature. The increase in resolution is especially important because of the size of hurricanes. The eyewall, the layer of clouds surrounding the eye, varies in size but is roughly 6 miles thick. Using GOES-13 brightness temperatures with 2.5-mile resolution, the eyewall is often grouped together with other parts of the storm, with only one or two brightness temperature measurements from only the eyewall itself. A 0.6 mile resolution brightness temperature measurement would allow for up to 10 eyewall measurements to be fed into prediction models as separate chunks of information instead of grouped together with other parts of the storm.

This new data source could have implications on the longstanding challenge of predicting hurricane intensity, Zhang said. Researchers know that wind speed and other levels of activity near the eye of the hurricane are linked to future intensity, but actually collecting these data is difficult. Today, NOAA uses airborne reconnaissance to collect data, but this is only possible when the storm is within flying distance. Satellites that constantly monitor the oceans at high spatial and temporal resolution and with many frequencies of brightness temperature, like GOES-R, could remove that constraint.

"Geostationary satellites are there all the time, which makes them ideal for capturing the initial and evolving states of hurricanes, including the crucial information in the cloudy region of the storm," said Zhang. "Using satellite data more effectively could potentially revolutionize hurricane monitoring and prediction for many years."

Phone-based laser rangefinder works outdoors

Depth sensor built from off-the-shelf parts filters out ambient infrared light

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CSAIL researchers are presenting a new infrared depth-sensing system built from off-the-shelf components, that works outdoors as well as in.

Credit: Christine Daniloff/MIT

The Microsoft Kinect was a boon to robotics researchers. The cheap, off-the-shelf depth sensor allowed them to quickly and cost-effectively prototype innovative systems that enable robots to map, interpret, and navigate their environments.

But sensors like the Kinect, which use infrared light to gauge depth, are easily confused by ambient infrared light. Even indoors, they tend to require low-light conditions, and outdoors, they're hopeless.

At the International Conference on Robotics and Automation in May, researchers from MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL) will present a new infrared depth-sensing system, built from a smartphone with a $10 laser attached to it, that works outdoors as well as in.

The researchers envision that cellphones with cheap, built-in infrared lasers could be snapped into personal vehicles, such as golf carts or wheelchairs, to help render them autonomous. A version of the system could also be built into small autonomous robots, like the package-delivery drones proposed by Amazon, whose wide deployment in unpredictable environments would prohibit the use of expensive laser rangefinders.

"My group has been strongly pushing for a device-centric approach to smarter cities, versus today's largely vehicle-centric or infrastructure-centric approach," says Li-Shiuan Peh, a professor of electrical engineering and computer science whose group developed the system. "This is because phones have a more rapid upgrade-and-replacement cycle than vehicles. Cars are replaced in the timeframe of a decade, while phones are replaced every one or two years. This has led to drivers just using phone GPS today, as it works well, is pervasive, and stays up-to-date. I believe the device industry will increasingly drive the future of transportation."

Joining Peh on the paper is first author Jason Gao, an MIT PhD student in electrical engineering and computer science and a member of Peh's group.

Background noise

Infrared depth sensors come in several varieties, but they all emit bursts of laser light into the environment and measure the reflections. Infrared light from the sun or human-made sources can swamp the reflected signal, rendering the measurements meaningless.

To compensate, commercial laser rangefinders use higher-energy bursts of light. But to limit the risk of eye damage, those bursts need to be extremely short. And detecting such short-lived reflections requires sophisticated hardware that pushes the devices' cost into the thousands of dollars.

Gao and Peh's system instead performs several measurements, timing them to the emission of low-energy light bursts. Essentially, it captures four frames of video, two of which record reflections of laser signals and two of which record only the ambient infrared light. It then simply subtracts the ambient light from its other measurements.

In their prototype, the researchers used a phone with a 30-frame-per-second camera, so capturing four images imposed a delay of about an eighth of a second. But 240-frame-per-second cameras, which would reduce that delay to a 60th of a second, are already commercially available.

The system uses a technique called active triangulation. The laser, which is mounted at the bottom of the phone in the prototype, emits light in a single plane. The angle of the returning light can thus be gauged from where it falls on the camera's 2-D sensor.

Global replace

At ranges of 3 to 4 meters, the system gauges depth to an accuracy measured in millimeters, while at 5 meters, the accuracy declines to 6 centimeters. The researchers tested their system on a driverless golf cart developed by the Singapore-MIT Alliance for Research and Technology and found that its depth resolution should be adequate for vehicles moving at rates of up to 15 kilometers per hour.

Imminent advances in camera technology could improve those figures, however. Currently, most cellphone cameras have what's called a rolling shutter. That means that the camera reads off the measurements from one row of photodetectors before moving on to the next one. An exposure that lasts one-thirtieth of a second may actually consist of a thousand sequential one-row measurements.

In Gao and Peh's prototype, the outgoing light pulse thus has to last long enough that its reflection will register no matter which row it happens to strike. Future smartphone cameras, however, will have a "global shutter," meaning that they will read off measurements from all their photodetectors at once. That would enable the system to emit shorter light bursts, which could consequently have higher energies, increasing the effective range.

Printing nanomaterials with plasma

New method can deposit nanomaterials onto flexible surfaces and 3-D objects,

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The nozzle firing a jet of carbon nanotubes with helium plasma off and on. When the plasma is off, the density of carbon nanotubes is small. The plasma focuses the nanotubes onto the substrate with high density and good adhesion.

Credit: NASA Ames Research Center

Printing has come a long way since the days of Johannes Gutenberg. Now, researchers have developed a new method that uses plasma to print nanomaterials onto a 3-D object or flexible surface, such as paper or cloth. The technique could make it easier and cheaper to build devices like wearable chemical and biological sensors, flexible memory devices and batteries, and integrated circuits.

One of the most common methods to deposit nanomaterials--such as a layer of nanoparticles or nanotubes--onto a surface is with an inkjet printer similar to an ordinary printer found in an office. Although they use well-established technology and are relatively cheap, inkjet printers have limitations. They can't print on textiles or other flexible materials, let alone 3-D objects. They also must print liquid ink, and not all materials are easily made into a liquid.

Some nanomaterials can be printed using aerosol printing techniques. But the material must be heated several hundreds of degrees to consolidate into a thin and smooth film. The extra step is impossible for printing on cloth or other materials that can burn, and means higher cost for the materials that can take the heat.

The plasma method skips this heating step and works at temperatures not much warmer than 40 degrees Celsius. "You can use it to deposit things on paper, plastic, cotton, or any kind of textile," said Meyya Meyyappan of NASA Ames Research Center. "It's ideal for soft substrates." It also doesn't require the printing material to be liquid.

The researchers, from NASA Ames and SLAC National Accelerator Laboratory, describe their work in Applied Physics Letters, from AIP Publishing.

They demonstrated their technique by printing a layer of carbon nanotubes on paper. They mixed the nanotubes into a plasma of helium ions, which they then blasted through a nozzle and onto paper. The plasma focuses the nanoparticles onto the paper surface, forming a consolidated layer without any need for additional heating.

The team printed two simple chemical and biological sensors. The presence of certain molecules can change the electrical resistance of the carbon nanotubes. By measuring this change, the device can identify and determine the concentration of the molecule. The researchers made a chemical sensor that detects ammonia gas and a biological sensor that detects dopamine, a molecule linked to disorders like Parkinson's disease and epilepsy.

But these were just simple proofs-of-principle, Meyyappan said. "There's a wide range of biosensing applications." For example, you can make sensors that monitor health biomarkers like cholesterol, or food-borne pathogens like E. coli and Salmonella.

Because the method uses a simple nozzle, it's versatile and can be easily scaled up. For example, a system could have many nozzles like a showerhead, allowing it to print on large areas. Or, the nozzle could act like a hose, free to spray nanomaterials on the surfaces of 3-D objects.

"It can do things inkjet printing cannot do," Meyyappan said. "But anything inkjet printing can do, it can be pretty competitive."

The method is ready for commercialization, Meyyappan said, and should be relatively inexpensive and straightforward to develop. Right now, the researchers are designing the technique to print other kinds of materials such as copper. They can then print materials used for batteries onto thin sheets of metal such as aluminum. The sheet can then be rolled into tiny batteries for cellphones or other devices.

First prosthesis in the world with direct connection to bone, nerves and muscles

Magnum using his prosthesis.

Thanks to the electrodes system a stable signal is obtained, which allows precise control like handling an egg without breaking. It also provides sensations as if it were a real hand.

The first prosthesis in the world that connects directly to the bone, nerves and muscles, allows the person to experience sensations, free mobility and is handled using the mind.

It was created by the Mexican Max Ortiz Catalan, who lives in Sweden, the device becomes an extension of the human body through osseointegration, this means that it connects directly to the bone via a titanium implant, and thanks to the neuronal and muscle binding interfaces a robust and intuitive control of the artificial hand is achieved, this way just by thinking about it is possible to move the limb.

The Mexican graduated from the Tecnológico de Monterrey says that Magnus, a patient with an arm amputated above the elbow, is the first person to use technology and, since 2013, it has allowed him to develop a normal working life, return to his activity as operator of heavy machinery on the border between Sweden and Finland, as well as manipulate an egg without breaking it.

The doctor in biomedical engineering Ortiz Catalan explains that thanks to the electrodes that are connected in muscles and nerves stable signals that allow precise control, such that the patient handling a small and delicate items without breaking it or throw it obtained, also provides sensations as his own hand and is protected from interference such as sensors in retail stores.

The research was conducted at Chalmers Technological University in Gothenburg, Sweden, in collaboration with the Sahlgrenska University Hospital, and the implant company called Integrum AB, which works with bone anchoring prosthetics.

Setting up

The device consists of two parts, an implant and a prosthesis, the first part requires surgery in which a titanium piece is placed into the bone and a control system that connect electrodes to the muscles and nerves is installed.

The second corresponds to a removable prosthesis, maintaining a mechanical connection with the bone and an electrical connection with the implanted electrodes. This robotic component can be taken off, so the patient can get wet and have a bath.

About 400 people worldwide already have a titanium implant, but only two count with the system of electrodes implanted in nerves and muscles. It is expected that this year more than ten patients receive the neural control system.

New technology

Technology osseointegration puts an end to inflammation problems, chafing and discomfort that conventional prosthesis cause. "This one strongly presses the stump, it feels like having shoes half a size to small, which is not comfortable; however, by having a direct connection to the bone and not having any components that disturb the skin, the use increases considerably, as well as the quality of life ."

In addition, by having a titanium implant allows the bone to grow around it and bind between them, which would not happen with other materials such as stainless steel which generates a reaction of encapsulation and creates mechanical instability.

The titanium implant to anchor the prosthesis to the bone is only available in Europe, Australia, Chile and the United States, but agreements are being sought to develop it in Mexico.

"We aim to make technology that people can use in their daily activities, and we would like it to become a standard treatment for every amputation, thus prices would fall," concludes Dr. Ortiz Catalan.

Breakthrough technology to improve cyber security

An international research team has made a breakthrough in generating single photons, as carriers of quantum information in security systems. The interdisciplinary research is set to revolutionize our ability to exchange data securely -- along with advancing quantum computing, which can search large databases exponentially faster.

Photons are generated simultaneously in pairs, each in one of the photon streams. The detection of photons in one stream indicates the timing information of those in the other. Using this information, a proper timing control is dynamically applied to those photons so they appear at regular intervals. This new technique increases the rate of photons at the regular interval, which is extremely useful for quantum secure communication and quantum photonic computation.

Credit: University of Sydney

With enough computing effort most contemporary security systems will be broken. But a research team at the University of Sydney has made a major breakthrough in generating single photons (light particles), as carriers of quantum information in security systems.

The collaboration involving physicists at the Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), an ARC Centre of Excellence headquartered in the School of Physics, and electrical engineers from the School of Electrical and Information Engineering, has been published inNature Communications.

The team's work resolved a key issue holding back the development of password exchange which can only be broken by violating the laws of physics. Photons are generated in a pair, and detecting one indicates the existence of the other. This allows scientists to manage the timing of photon events so that they always arrive at the time they are expected.

Lead author Dr Chunle Xiong, from the School of Physics, said: "Quantum communication and computing are the next generation technologies poised to change the world."

Among a number of quantum systems, optical systems offer particularly easy access to quantum effects. Over the past few decades, many building blocks for optical quantum information processing have developed quickly," Dr Xiong said.

"Implementing optical quantum technologies has now come down to one fundamental challenge: having indistinguishable single photons on-demand," he said.

"This research has demonstrated that the odds of being able to generate a single photon can be doubled by using a relatively simple technique -- and this technique can be scaled up to ultimately generate single photons with 100% probability."

CUDOS director and co-author of the paper, Professor Ben Eggleton, said the interdisciplinary research was set to revolutionise our ability to exchange data securely -- along with advancing quantum computing, which can search large databases exponentially faster.

"The ability to generate single photons, which form the backbone of technology used in laptops and the internet, will drive the development of local secure communications systems -- for safeguarding defence and intelligence networks, the financial security of corporations and governments and bolstering personal electronic privacy, like shopping online," Professor Eggleton said.

"Our demonstration leverages the CUDOS Photonic chip that we have been developing over the last decade, which means this new technology is also compact and can be manufactured with existing infrastructure."

Co-author and Professor of Computer Systems, Philip Leong, who developed the high-speed electronics crucial for the advance, said he was particularly excited by the prospect of further exploring the marriage of photonics and electronics to develop new architectures for quantum problems.

"This advance addresses the fundamental problem of single photon generation -- promises to revolutionise research in the area," Professor Leong said.

Engineers adapt laser method to create micro energy units

Laser-writing technique can help manufacturers create micro energy storage and conversion units; possibilities are 'endless,' researchers say,

As the demand for thinner microelectronic devices increases, manufacturers often are limited by how oddly shaped the energy sources must become to make them conform to the smaller space. Now, researchers have developed a method of transferring an energy source to virtually any shape. Using direct laser-writing techniques, scientists can help smartphone manufacturers fabricate energy storage units such as micro fuel cells that are environmentally friendly, highly designable and thin.

Assistant Professor Jian Lin and his team developed a technique using direct laser writing methods. The team created a way of synthesizing hybrid nanocatalysts into any patterned geometric shape, including the Mizzou Tigers logo.

In the race to design smaller handheld devices and smartphones, a key factor is decreasing the sizes of components. As the demand for thinner and lighter microelectronic devices increases, manufacturers often are limited by how oddly shaped the energy sources must become to make them conform to the smaller space. Now, researchers at the University of Missouri, have developed a method of transferring an energy source to virtually any shape. Using an efficient laser-writing technique, MU scientists can help smartphone manufacturers potentially fabricate energy storage units like microbatteries and micro fuel cells that are more environmentally friendly, highly designable and thin.

"The direct laser writing (DLW) method and technique has seen a rapid advancement in the past decade," said Jian Lin, an assistant professor in the Department of Mechanical and Aerospace Engineering in the MU College of Engineering. "The main goal of our research was to find an efficient and cost-effective way to integrate nanostructures with micro energy storage units for applications in micro-electronics. Our lab decided to test whether catalysts could be synthesized and patterned on any surface by a one-step laser processing method to produce microbatteries and micro fuel cells in the shapes dictated by computer programs."

With this in mind, Lin and his team, including Heng (Henry) Deng, a doctoral candidate at MU, set out to prove their theory. They adapted the DLW method to synthesize and pattern hybrid nanocatalysts, or fuel sources, into complex geometric shapes. Using computer-controlled laser writing that uses higher heat and pressure, the scientists were able to produce a surface that became electrically conducive and also has catalytic functionalities.

"This is the first step in manufacturing micro fuel cells that convert chemical energy into electrical energy and batteries that can integrate into microcircuits" said Lin. "Also this technique has been proven to produce microsupercapacitors. By honing the process, handheld device and smartphone manufacturers will be able to produce components in whatever shape or size they choose, greatly impacting the size of these devices. Also, manufacturers will be able to choose more environmentally friendly catalysts for generating energy such as hydrogen or oxygen, which are considered cleaner fuels. The possibilities will be endless."

The paper, "Laser induced MoS2/carbon hybrids for hydrogen evolution reaction catalysts," recently was published in a special issue of "Emerging Investigators 2016: Novel Design Strategies for New Functional Materials" in the Journal of Materials Chemistry-A.

Plastic that mimics insect wings kills bacteria

The curved plastic may one day be used as an artificial cornea

Tiny pillars on insect wings inspired scientists and engineers to make polymer nanopillars that can kill bacterial cells on this artificial cornea.

A new plastic that mimics the surface of insect wings might help save people’s eyesight. More than 40,000 people each year need a transplant for the front part of the eye, called the cornea. But donors aren’t always available. Also, some people’s bodies won’t accept a replacement from someone else. And bacteria could easily infect materials for artificial ones — at least until now.  
Researchers at the University of California (UC), Irvine have made an antibacterial material with thousands of teeny, spike-like pillars. Each pillar is like one of the invisible hairs on a cicada wing. And like the insect wings, the surface kills various types of bacterial cells. Better still, such surfaces can be shaped in a curve, just like the eye is.

This cicada's wings may appear shiny and smooth. But they actually host germ-impaling hair-like spikes.

BRUCE MARLIN/WIKIMEDIA COMMONS

The idea for the project came about because scientists and engineers in different fields shared ideas. Albert Yee is a materials scientist at UC Irvine. He works in nanotechnology. That field deals with structures on the scale of less than 100 billionths of a meter. That’s roughly one ten-thousandth the diameter of a human hair. Yee had formed nanostructures for computer chips using polymers. Such materials, which include plastics, have molecules that are chains of repeating groups of atoms.
Yee learned about medical researchers wanting to mimic the surfaces of wings on cicadas and dragonflies. Bacteria die after landing on those surfaces. The microbes jab themselves into the nanospikes on those wings. Essentially, they spear themselves to death.
Yee and his colleagues decided to see if ideas from the earlier work might help keep plastic corneas similarly germ-free. His group chose a plastic called PMMA. It’s short for polymethylmethacrylate (POL-ee-METH-ul-meh-THAK-rih-LATE). They used a readily available mold to make it into spikey nanopillars. The flat mold had thousands of tiny indentations. Heated PMMA was pressed against the mold. Later, the cooled PMMA came out bearing nanospikes like those on cicada wings. In tests, this surface killed lots of thin-walled bacteria, such as E. coli.
But a cornea is curved, not flat. And just as a paper wrinkles as you press it around a baseball, flat polymers get distorted around curved shapes. To deal with that, the group made a new curved mold. Cooled PMMA comes out of this mold already curved.

The cornea is a clear protective outer covering of the front, vision-sensing structures on the eyeball.

“We’ve done initial testing to prove that it will work for the cornea device,” says Mary Nora Dickson. This chemical engineer is a graduate student at UC Irvine and a member of the research team. She and fellow graduate student Elena Liang reported on their team’s work on March 16 in San Diego at the spring meeting of the American Chemical Society.

The next challenge

The researchers now hope to tweak their material so that it will kill bacteria with cell walls thicker than E. coli. This would fight infections such as staph (caused by Staphylococcus germs). The trick requires building taller nanospikes, like those on dragonfly wings. But, notes Dickson, “It’s actually pretty difficult to make polymers into skinny shapes without damaging them.”
As molecules go, polymer chains are “kind of like spaghetti,” she explains. “It might be easy to put spaghetti into a big bowl. If you tried to put it into something skinny, like a vase, it will get harder and harder to push that spaghetti into that skinny shape.” Getting the material out of the mold also gets harder as the pillars grow taller.
Her team is now applying coatings to the molds for the plastic to see if that helps. A light spray of oil makes it easier to get cupcakes out of a tin. The group hopes its coatings might do the same thing for the nanospikes on their plastic.
This new research adds to other studies probing how to tweak the form and structure of materials at the smallest scales. Taken together, they show “you can profoundly affect the way cells interact with a given surface,” says Masaru Rao. He’s a materials engineer at the University of California, Riverside. That principle could work for other medical uses as well, he suspects.
Also, the ability to kill bacteria comes from the material’s structure. In contrast, most other antibacterial materials have a coating. So, Rao says, this new approach “may yield greater reliability and damage-resistance.” The process for making the nanospike-shaped plastic also can be scaled up. So low-cost production of medical devices might be possible.
Before that happens, additional tests must take place. The team needs more proof of the material’s germ-killing abilities, of how long the material can do its job, and if there are any side effects.
Meanwhile, Rao observes, “There’s still much we can learn from nature.
”

New football helmets could limit brain injuries

New football helmets could limit brain injuries

Their three layers are better than having just one

The purple area in this image represents the kinetic energy that spreads across a football player’s helmet and into the brain when head-to-head contact is made. Colors in the brain show where  that energy flows as it continues to move and threaten injury. 

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This is one in a series presenting news on invention and innovation, made possible with generous support from the Lemelson Foundation.

Two football players collide on the field. Both are wearing helmets. Still, their heads bang together, risking serious injury. A new helmet design might offer these players’ brains much better protection. Key to its advantage: three layers of energy-absorbing insulation. Most helmets today offer just a single layer.
“Current helmets do a good job of reducing the force that gets to the skull,” says Ellen Arruda. She’s a mechanical engineer at the University of Michigan in Ann Arbor. But reducing force isn’t the only problem. A blow to the head sends waves of kinetic (Ki-NET-ik) energy through the skull and into the brain. Kinetic energy is the energy of motion.

“Let’s imagine you have an egg and you hit the egg,” explains Michael Thouless, also a mechanical engineer at Michigan. Hitting the egg could crack its shell. But the impulse of kinetic energy might also send the egg flying.

Something similar happens when an athlete’s head gets hit. Even if the skull doesn’t crack, an impulse of energy travels through the skull and brain. But the brain and skull don’t always move at the same speed. So parts of the brain can crash against the inside of the skull.

Bike helmets are made to crush, or deform, on impact. That action absorbs a good deal of the kinetic energy. Afterward, however, the helmet must be thrown out. That’s not practical for football and other contact sports. And helmets for those sports do a poor job of cutting down on that kinetic energy, says Arruda.

Ellen Arruda shows the three-layer design that her team at the University of Michigan developed to better cushion the head during collisions on the field.

EVAN DOUGHERTY/MICHIGAN ENGINEERING

Now the two Michigan engineers have worked with graduate student Tanaz Rahimzadeh to improve the standard helmet. Their new design uses three layers of polymers, plastic materials whose molecules are chains of repeating groups of atoms. Together the three layers reduce both the force of an impact and the kinetic energy of the impulse.

Different layers, different functions

The team tackled the project in response to Head Health Challenge III. This competition is part of a four-year program sponsored by the National Football League (NFL), the National Institute of Standards and Technology and others. The overall goal of the program is to provide better protection from brain injuries.
The Michigan team focused first on the head, which is where the damage occurs. “We analyzed what causes the brain to move relative to the skull when you hit the skull,” Arruda explains. Understanding the movement and the factors that cause it led her team to its three-layered design.

Next the team picked out polymers. “We knew what properties we were looking for,” says Thouless. With that knowledge, the team looked through catalogs for materials to find “a combination that seemed to work.”
To sop up kinetic energy, the team chose a viscous (VIS-kus) elastomer for the innermost layer. Like elastic, this material bounces back to its original shape after something deforms it. Unlike regular elastic, however, the material returns to that shape slowly. The memory foam in some mattresses and pillows is an example of this type of material.

As the material changes form and recovers, it sheds some of its kinetic energy. This means that in a helmet, less of that energy would get through to the head. How much less depends on the specific type of polymer. It also depends on the frequency, or wavelength, of the impulse. For any particular viscous elastomer, there’s one frequency of energy that it sheds best.

However, a single impact doesn’t send an impulse with just one frequency, notes Thouless. Instead, the impulse spreads across the helmet and into the head at a range of frequencies. It’s kind of like hitting a bunch of piano keys with your fist. You’d hear a bunch of clashing notes with different frequencies.

That’s where the other two layers of the design come in. As in standard helmets, the outer two layers absorb a good deal of the force of an impact. Basically, they soften the blow.

Those layers also work together to change the group of frequencies from an impact into just one frequency. It’s a bit like an orchestra tuning up to match a single note. The frequencies bounce between those two layers. When the energy finally passes through, it’s tuned to the one frequency that works best with the innermost layer, explains Christian Franck. He’s an engineer at Brown University in Providence, R.I., who did not work on the project.

More than football players may benefit

The group’s prototype worked well. Compared to other helmets, only one-fifth of the kinetic energy from an impact made it through to the head. The team described its results in the December 2015 issue of the Journal of the Mechanics and Physics of Solids.

The design is now one of five finalists in the Head Health Challenge competition. Over the next year, the team will do more work to further improve its design. For instance, the group plans to experiment with other polymers.

Franck describes the new helmet as “a very clever design.” He also has studied how energy from an impact affects the brain. “I like the idea of reducing energy from the impact before it hits the brain,” he says. “I absolutely believe that’s the right approach.”

“This helmet doesn’t have to cost anything more than an existing helmet,” says Arruda. That means athletes at any age could benefit if they play any contact sport, such as rugby or soccer.

“The same design can be used in other applications,” she adds. For example, multiple layers could help improve the shoulder and knee pads used in some sports. The layered approach also might help make playground surfaces safer.
Ideally, the new approach will lead to fewer concussions, a type of traumatic brain injury. “The brain is a very delicate structure, and it should be protected at all costs,” says Franck.