Field effect transistors (FETs) composed of discrete silicon active regions or ‘fins’, referred to as finFETs, have superior electrostatic properties compared to planar devices  As a result, they are likely to play a role in further miniaturization of electronic devices.  However, density requirements for fin patterning have exceeded what can be achieved through direct printing by 193nm immersion (193i) lithography.  Consequently, sublithographic patterning techniques that can extend the resolution of 193i to the sub-80nm pitch regime are now of vital importance.  [SPIE News, 5 Apr 2013]

It is presently believed that flows of viscoelastic polymer solutions in geometries such as a straight pipe or channel are linearly stable.  Here we present experimental evidence that such flows can be nonlinearly unstable and can exhibit a subcritical bifurcation.  Velocimetry measurements are performed in a long, straight microchannel; flow disturbances are introduced at the entrance of the channel system by placing a variable number of obstacles.  Above a critical flow rate and a critical size of the perturbation, a sudden onset of large velocity fluctuations indicates the presence of a nonlinear subcritical instability.  Together with the previous observations of hydrodynamic instabilities in curved geometries, our results suggest that any flow of polymer solutions becomes unstable at sufficiently high flow rates.  [Physical Review Letters, 23 Apr 2013]

Soft robotics offers the unique promise of creating inherently safe and adaptive systems.  These systems bring man-made machines closer to the natural capabilities of biological systems.  An important requirement to enable self-contained soft mobile robots is an on-board power source.  In this paper, we present an approach to create a bio-inspired soft robotic snake that can undulate in a similar way to its biological counterpart using pressure for actuation power, without human intervention.  With this approach, we develop an autonomous soft snake robot with on-board actuation, power, computation and control capabilities.  The robot consists of four bidirectional fluidic elastomer actuators in series to create a traveling curvature wave from head to tail along its body.  Passive wheels between segments generate the necessary frictional anisotropy for forward locomotion.  It takes 14 hours to build the soft robotic snake, which can attain an average locomotion speed of 19 mm s-1.  [Bioinspiration & Biomimetics, June 2013]

Urban population now exceeds rural population globally, and 60–80% of global energy consumption by households, businesses, transportation, and industry occurs in urban areas. There is growing evidence that built-up infrastructure contributes to carbon emissions inertia, and that investments in infrastructure today have delayed climate cost in the future. Although the United Nations statistics include data on urban population by country and select urban agglomerations, there are no empirical data on built-up infrastructure for a large sample of cities. Here we present the first study to examine changes in the structure of the world’s largest cities from 1999 to 2009. Combining data from two space-borne sensors—backscatter power (PR) from NASA’s SeaWinds microwave scatterometer, and nighttime lights (NL) from NOAA’s defense meteorological satellite program/operational linescan system (DMSP/OLS)—we report large increases in built-up infrastructure stock worldwide and show that cities are expanding both outward and upward. Our results reveal previously undocumented recent and rapid changes in urban areas worldwide that reflect pronounced shifts in the form and structure of cities. Increases in built-up infrastructure are highest in East Asian cities, with Chinese cities rapidly expanding their material infrastructure stock in both height and extent. In contrast, Indian cities are primarily building out and not increasing in verticality. This new dataset will help characterize the structure and form of cities, and ultimately improve our understanding of how cities affect regional-to-global energy use and greenhouse gas emissions.  [Environmental Research Letters, June 2013]

Flies are among the most agile flying creatures on Earth.  To mimic this aerial prowess in a similarly sized robot requires tiny, high-efficiency mechanical components that pose miniaturization challenges governed by force-scaling laws, suggesting unconventional solutions for propulsion, actuation, and manufacturing.  To this end, we developed high-power-density piezoelectric flight muscles and a manufacturing methodology capable of rapidly prototyping articulated, flexure-based sub-millimeter mechanisms.  We built an 80-milligram, insect-scale, flapping-wing robot modeled loosely on the morphology of flies.  Using a modular approach to flight control that relies on limited information about the robot’s dynamics, we demonstrated tethered but unconstrained stable hovering and basic controlled flight maneuvers.  The result validates a sufficient suite of innovations for achieving artificial, insect-like flight.  [Science, 3 May 2013]

Nanoparticles are finding increasing applications in diagnostics, imaging, and therapeutics in biology and medicine.  Gold nanoparticles (Au NPs) have received a great deal of interest because of their distinctive optical, electronic, and molecular-recognition properties, as well as biocompatibility.  One promising yet ambitious application for Au NPs is noncontact hyperthermia of cancer. By attaching tailor-made ligands, Au NPs can recognize and lock onto receptors on the surface of tumor cells.  Under illumination by light, Au NPs can absorb radiation energy and selectively heat and destroy tumor volumes without collateral damage to neighboring healthy tissue.  This type of noninvasive, specific, active targeting with Au NPs is highly desirable from a clinical perspective, but its use in cancer intervention has yet to be demonstrated.  [Science, 26 Apr 2013]

Engineers learn from mistakes.  The mantra “fail often, fail fast” is sometimes heard in the research and development environment and describes a spirit of exciting exploration, investigation, and innovation.  But the real world is a crucible for errors and flaws where the failure of functional designs can affect real people.  There is always a human face to engineering design decisions, and the result of an unanticipated coincidence of events or conditions is the stuff of nightmares for engineers.  Whether the result of failure is annoyance and embarrassment or catastrophe and tragedy, engineers use a systematic approach to discovering what went wrong.  [Science, 26 Apr 2013]

The goal of the Generation Three (Gen-3) Engineering Research Centers (ERC) Program is to create a culture in engineering research and education that integrates discovery with technological innovation to advance technology and produce graduates who will be creative U.S. innovators in a globally competitive economy.  These ERCs are at the forefront as the U.S. competes in the 21st century global economy where R&D resources and engineering talent are internationally distributed.  Recognizing that optimizing efficiency and product quality are no longer sufficient for U.S. industry to remain competitive, these ERCs integrate transformational academic engineering research and education to stimulate increased U.S. innovation in a global context.  In essence, this solicitation requires that effort be devoted to creating, developing, and enhancing capacities in ERCs to support the spectrum from transformational fundamental research to technological innovation and create pathways to success in engineering careers for diverse cadres of students from middle school to graduation with degrees in engineering.  Proposals are solicited in two tracks: (1) Open Topic ERCs, where the PI’s are free to structure the engineered systems vision and research program without restrictions on the research content, and (2) Nanosystems ERCs (NERCs), where the PIs are free to structure the engineered systems vision but the research program must include a substantial body of nanoscale fundamental research.

The advent of the first cellphones in the 1980s marked the beginning of commercial mobile communications.  Now, only 30 years later, wireless connectivity has become a fundamental part of our everyday lives and is increasingly being regarded as an essential commodity like electricity, gas, and water.  The technology’s huge success means we are now facing an imminent shortage of radiofrequency (RF) spectrum.  The amount of data sent through wireless networks is expected to increase 10-fold during the next four years.  At the same time, there isn’t enough new RF spectrum available to allocate.  In addition, the spectral efficiency (the number of bits successfully transmitted per Hertz bandwidth) of wireless networks has become saturated, despite tremendous technological advancements in the last 10 years.  The US Federal Communications Commission has therefore warned of a potential spectrum crisis.  [SPIE Newsroom, 19 Apr 2013]

In November 2012, IBM announced that it had used the Blue Gene/Q Sequoia supercomputer to achieve an unprecedented simulation of more than 530 billion neurons.  The Blue Gene/Q Sequoia accomplished this feat thanks to its blazing fast speed; it clocks in at over 16 quadrillion calculations per second.  In fact, it currently ranks as the second-fastest supercomputer in the world.  But, according to Kwabena Boahen, Ph.D., the Blue Gene still doesn’t compare to the computational power of the brain itself.  [NSF Discoveries, 24 Apr 2013]