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When Pantelis Georgiou and his fellow biomedical engineers at Imperial College London decided to design an intelligent insulin pump for diabetes patients, they started at the source. "We asked ourselves, what does a pancreas do to control blood glucose?" Georgiou recalls. The answer is pretty well known: The organ relies primarily on two populations of cells—beta cells, to secrete insulin when blood glucose is high, and alpha cells, which release a hormone called glucagon when glucose levels are low. "We simulated them both in microchip form," Georgiou says. This biomimetic approach diverges from today's dominant method of delivering only insulin using a relatively simple control system.

The IEEE has launched a new Web site that consolidates information about smart electric grids from it various societies. The portal is one of many activities from an IEEE smart grid initiative coordinating the organization's work on the transition to digital, networked power systems and services. The smart grid is "so interdisciplinary," said Wanda Reder, chair of the IEEE Smart Grid Task Force and former president of the IEEE Power & Energy Society. "We have the gamut covered in technical interests, but we needed a way to facilitate communications between our many entities to link information on all the conferences, papers and standards we have in this area," she added.

Ever since graphene was first produced in a lab at the University of Manchester in 2004, researchers around the world have been fascinated with its potential in electronics applications. Graphene possessed all the benefits of carbon nanotubes (CNTs), namely its charged-carrier mobility, but it didn’t have any of the down sides, such as CNTs’ need for different processing techniques than silicon and the intrinsic difficulty of creating interconnects for CNTs. But all was not easy for applying graphene to electronics applications. One of the fundamental problems for graphene was its lack of a band gap, which left it with a very low on-off ratio measured at about 10 as compared to in the 100s for silicon. Now this fundamental hurdle has been overcome. Based on research led by Phaedon Avouris at IBM’s IBM T.J. Watson Research Center, Yorktown Heights, New York, IBM is reporting that they have created a significant band gap in graphene.

Three-dimensional microchip designs are making their way to market to help pack more transistors on a chip as traditional scaling slows down. By stacking logic chips on top of one another other or combining logic chips with memory or RF with logic, chipmakers hope to sidestep Moore's Law, increasing the functionality of smartphones and other gadgets not by shrinking a chip's transistors but the distance between them. "There's a big demand for smaller packages in the consumer market, especially for the footprint of a mobile phone, or for improving the memory bandwidth of your GPU," says Pol Marchal, a principal scientist of 3-D integration at European microelectronics R&D center Imec. On 9 February, at the IEEE International Solid-State Circuits Conference (ISSCC), in San Francisco, Imec engineers presented some key design challenges facing 3-D chips made by stacking layers of silicon circuits using vertical copper interconnects called through-silicon vias (TSVs). These design constraints will have to be dealt with before TSVs can be widely used in advanced microchip architectures, Marchal says.

The race to create tiny wireless sensors that could monitor anything from pressure in the eyes and brain to the stability of bridges appears to be heating up. Earlier this month, IEEE Spectrum reported on two approaches to creating an almost-indefinitely-running sensor using piezoelectric systems to convert tiny vibrations into power. Now, another team from the University of Michigan has created an alternative approach that uses solar power to keep the sensor running autonomously for many years.

It’s 2020, and it’s sunny outside. In fact, it’s so bright in your kitchen that you have to squint to see your grapefruit. You flip on your e-reader and the most recent e-issue of IEEE Spectrum pops up on-screen, the colors and text sharp and brilliant in the sunlight. There’s e-mail to answer, but you want to make the early commuter bus, so you roll up your e-reader and stuff it in your jacket pocket.

In a recent video, Willow Garage researcher Eitan Marder-Eppstein describes the open-source navigation stack they've released as version 1.0. The code, available at http://ros.org/wiki/navigation, was designed to be flexible and cross-platform, he says, and could be used in anything from a small iRobot Create-based bot to a large multi-sensor robot like Willow's own PR2 (which Spectrum has covered in detail here and here).

One of the biggest commercial applications of spintronics in computing to date has been the use of giant magnetoresistance (GMR), the material phenomenon that makes possible the huge storage capacity of today’s hard disk drives. In the awarding of the 2007 Nobel Prize in Physics, GMR was cited as the first big commercial application for nanotechnology. But extending the commercial application of spintronic-enabled systems beyond read heads for HDDs has proven to be a difficult task. One need only look at the seemingly endless travails of NVE Corporation, which in its financial results still shows it greatest revenue growth in contract research as opposed to product sales. While recent research from a team of researchers at Ohio State University and the University of Hamburg in Germany may not turn around the fortunes of spintronics in the short term, it does provide a way to better characterize the spin of electrons and thereby promises better ways of exploiting it for electronics applications. The researchers are reporting in Nature Nanotechnology that they have for the first time been able to create images of the spin direction of electrons.

4 January 2010—Though flexible devices such as roll-up displays have been promised for several years, their commercialization has been stalled by a missing ingredient: a flexible form of flash memory. But researchers at the University of Tokyo have recently developed an organic, floating-gate nonvolatile memory that behaves like flash memory, which may solve that problem. While silicon-based flash memory is fine for the mass data storage found in cellphones, digital music players, and thumb drives, fabricating it requires high processing temperatures, thus ruling out its production on flexible substrates like plastic. Organic semiconductors, however, can be processed at temperatures well below the melting point of most plastics. What's more, "the cost of flash memory is too high to use in applications that require large arrays of memory," says Tsuyoshi Sekitani, an assistant professor in the University of Tokyo's department of electrical and electronic engineering and one of the researchers who developed the new memory. "But we can print our organic memory on flexible substrates and over large areas using inkjet printers. So costs will be low."

In 2008 a team of physicists from Argonne National Laboratory, in Illinois, and other institutions stumbled upon an odd phenomenon. They called it superinsulation, because in many ways it was the opposite of superconductivity. Now they’ve worked out the theory behind it, potentially opening the doors to better batteries, supersensitive sensors, and strange new circuits. Superconductors lose all resistance once they fall below a certain temperature. In superinsulators, on the other hand, the resistance to the flow of electricity becomes infinite at very low temperatures, preventing any flow of electric current.

A new chink has been found in the cryptographic armor that protects bank transactions, credit-card payments, and other secure Internet traffic. And although programmers have devised a patch for it, clever hackers might still be able to break through. The hack, presented in March at a computer security conference in Dresden, Germany, involves lowering the input voltage on a computer’s cryptography chip set and collecting the errors that leak out when the power-starved chips try and (sometimes) fail to encode messages. Crooks would then use those errors to reconstruct the secret key on which the encryption is based. More important, say the hack’s creators, the same attack could also be performed from afar on stressed systems, such as computer motherboards that run too hot or Web servers that run too fast.

Rosie, the robot who kept house for the title family in "The Jetsons," a 1960s animated television show, has at last come alive—sort of. Before you'll see a robot slicing cucumbers in your kitchen, researchers will need to make these mechanical servants smarter. Here's how three teams are tackling this challenge.

Tiny semiconductor dots could lead to a new type of circuit based on magnetism rather than current flow. At least that’s the hope of researchers who’ve made the dots and are hoping to build them into a workable device. ”We want to make it into a so-called nonvolatile transistor,” says Kang Wang, head of the Device Research Laboratory at the University of California, Los Angeles. Such a ”spintronic” transistor would retain its logic state in the absence of current and require less power to switch a bit, reducing the electrical power required by a computer chip by as much as 99 percent. Wang’s research, supported in part by Intel, was published in March in the online version of Nature Materials. Where electronic transistors rely on the presence or absence of current to register the ones and zeros of digital logic, spintronic transistors depend on ”spin,” a quantum characteristic of the electron. Picture the electron as a rotating globe. When the north pole is pointing upward, that’s spin up; when pointing the other way, it’s spin down. When the spins of most electrons are aligned, the material is magnetic. When their spins are random, the material isn’t. An applied current can align or randomize the spins, allowing for spin-based switches.

A transistor that emits light and is made from organic materials could lead to cheaper digital displays and fast-switching light sources on computer chips, according to the researchers who built it. Small displays made from diodes of the same type of materials (organic light-emitting diodes, or OLEDs) are already in commercial production, but the transistor design could improve on those and lead to applications where OLEDs can’t go. The new organic light-emitting transistor (OLET) is much more efficient than previous designs. It has an external quantum efficiency—a key measure of how much light comes out per charge carrier pumped in—of 5 percent. An OLED based on the same material has a quantum efficiency of only 2 percent. Previous OLET designs had an efficiency of only 0.6 percent.

Not so long ago, artists routinely made their own paints using all sorts of odd ingredients: clay, linseed oil, ground-up insects—whatever worked. It was a crude and rather ad hoc process, but the results were used to create some of the greatest paintings in the world. Today I and other scientists are developing our own special paints. We’re not trying to compete with Vermeer or Gauguin, though. We hope to create masterpieces of a more technical nature: optoelectronic components that will make for better photovoltaic cells, imaging sensors, and optical communications equipment. And we’re not mixing and matching ingredients quite so haphazardly. Instead, we’re using our blossoming understanding of the world of nanomaterials to design the constituents of our paints at the molecular level.

On Monday, National Instruments announced one such platform. It's called LabView Robotics. In addition to LabView, the popular data-acquisition application, the package includes a bunch of tools specific to robotics. It can import codes in various formats (C, C++, Matlab, VHDL), offers a library of drivers for a wide variety of sensors and actuators, and has modules for implementation of real-time and embedded hardware. NI says engineers could use the package to both design and run their robotic systems. 

French service robotics company Robosoft has introduced a robot called Kompaï designed to assist elderly and disabled people and others who need special care. The mobile robot talks, understands speech, and can navigate autonomously. It reminds people of meetings, keeps track of shopping lists, plays music, and works as a videoconference system for users to talk with their doctors, for example. The video below is pretty awesome. It shows a senior at Broca Hospital, in Paris, interacting with the robot after receiving only a few minutes of training. The man asks the robot about the time, date, and whether he has any appointments that day; Kompaï gives answers in a computerized voice.

Experimental microbial fuel cells could turn bacteria into batteries that generate electricity from biomass. The key to this technology is the ability of bacteria to transfer electrons to their surroundings—for example, to the anode of a microbial fuel cell. But if the organisms have to be in direct contact with the anode, such devices would have to have extremely large surface areas. Researchers from Aarhus University, in Denmark, report today in the journal Nature that bacteria appear to conduct electricity while separated by several millimeters, at least a thousand times as far apart than previously demonstrated. The naturally occurring electric currents, if confirmed, would allow bacteria spaced at least 12 millimeters apart to communicate electrically. The discovery might lead to new paths to treating infection and a better understanding of microbial ecosystems.

25 March 2010—Nowadays, a phone that doesn’t know where it is or where it’s going can’t really call itself ”smart.” To orient themselves properly, smartphones require not just GPS capability but also an electronic compass, an accelerometer, and increasingly, digital gyroscopes. The point of a gyroscope is to sense any change in an object’s axis of rotation. Up until now, gyroscopes measured movement around the three axes with three sensors—one for pitch, one for yaw, and another for roll. At most, two of these sensors would be combined on a single die. The best you could do was, say, match up a 3- by 5- by 1-millimeter yaw sensor with a 4- by 5- by 1-mm sensor that would detect pitch and roll. But on 15 February, STMicroelectronics unveiled  a 4- by 4- by 1-mm gyroscope whose single sensing structure tracks all three angular motions. It’s a triumph of microelectromechanical systems (MEMS) engineering.