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2013年7月12日星期五

Surrey and Reading put GLOSS on satellite monitoring University of Surrey Universities - Electronics Research

Ensuring the UK plays a key role in providing satellite-sourced observation services – this is the aim of a new centre of excellence to monitor changes to the Earth and its ecosystem.

Scientists at the Universities of Surrey and Reading will work with researchers at the National Physical Laboratory (NPL) in the new collaboration, which is called Global Satellite Sensing (GLOSS). There will be increasing demand for such monitoring services, believe the universities, as the cost of putting satellites into orbit falls dramatically over the next decade.

According to the GLOSS announcement:

Working together with the Satellite Applications Catapult, the Centre aims to contribute to the UK Government’s drive to capture at least 10% of the predicted global space market of $400bn by 2030.
The aim is to develop ways of using the very latest advances in the new generation of small, lightweight and highly innovative satellites, being developed in the UK.
GLOSS will provide new satellite data services for meteorological purposes and use in disaster scenarios, as well as proving a wide range of services to commercial sectors, including energy resource management, urban and environmental monitoring, security and insurance industries.

“Bringing these world-leading research capabilities together within a single centre of excellence provides the UK with an unrivalled ability to provide expertise across a range of areas,” said Keith Robson, Director Enterprise and Growth at the University of Surrey.

“This includes everything from developing new low cost sensors, designing groups of small satellites that can work together which are called ‘swarms’, in-orbit calibration systems, data assimilation, data processing and visualisation.

Professor Robert Gurney, Director of Space and Earth Observation at the University of Reading said: “This centre provides a unique opportunity for scientists and engineers to work collaboratively on research with the potential to deliver breakthrough technologies and applications for a changing planet.

“British scientists are among the best in the world at using data from satellites to provide vital information about weather and climate. By helping to develop the next generation of satellite technology, this collaboration will help to expand the range of information available to businesses and industry, such as real-time data. Such crucial and affordable information will help to give British businesses the cutting edge, boosting innovation and economic growth.”

Reading University reportedly has the largest research capability in weather and climate science and earth observation of any university in Europe.

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EPSRC funds launch of power electronics research centre University of Warwick Universities - Electronics Research

PowerelectronicsUK Forum Funding of £18 million from the Engineering and Physical Sciences Research Council (EPSRC) has helped launch a Centre for Power Electronics. It will focus on the science and engineering behind low carbon technologies such as electric vehicles and renewable energy generation and distribution.

Ten universities who initially benefit from research funding for the new centre: Bristol, Cambridge, Greenwich, Imperial, Manchester, Newcastle, Nottingham, Sheffield, Strathclyde and Warwick.

The Centre will be funded as five linked grants, one funding the main hub activity, led by the University of Nottingham, and four funding high-level technical research themes: Devices, Components, Converters and Drives.

Details of the themes, according to EPSRC:

Devices: Led by Professor Phil Mawby at the University of Warwick and involving the universities of Bristol, Cambridge, and Newcastle.
Components: Led by Professor Philip Mellor at the University of Bristol and involving the universities of Greenwich, Nottingham, Manchester, Warwick and Imperial College London.
Convertors: Led by Professor Andrew Forsyth at the University of Manchester and involving the universities of Strathclyde, Nottingham, Bristol and Imperial College London.
Drives: Led by Professor Barrie Mecrow at the University of Newcastle and involving the universities of Manchester, Nottingham, Sheffield and Bristol.

“We have a leading power electronics industry in the UK, but we need to keep investing in research to ensure it remains globally competitive. This National Centre will bring together our excellent universities and businesses to ensure industry has access to the latest science and technology, as well as helping to maintain a supply of skilled people,” said Minister for Universities and Science, David Willetts.

“This £18 million investment in a six-year research initiative is part of EPSRC’s response to the Government’s 2011 BIS Strategy for Power Electronics in the UK,” said EPSRC’s Chief Executive, Professor David Delpy. “We will invest an initial tranche of £12 million with a further £6 million being released subject to a future review of progress. Power Electronics was also a priority area in our recent call for new Centres for Doctoral Training.”

The opening of the new Centre, states EPSRC, comes two months after the launch (pictured) of the PowerelectronicsUK Forum, a network backed by industry, academia and the government that aims to boost the number of people within the Power Electronics industry.

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4 RoHS2 substances down to 3 EU RoHS Directive Decoder

Within the text of RoHS2 (2011/65/EU), four substances were identified for priority assessment with a view to a potential restriction.

Dr Paul Goodman of ERA Technology has provided a brief update on the current status.

Looking at some of the points of interest the HBCDD flame retardant will be banned by the POPs (Persistent Organic Pollutants) Regulation and, as this has been confirmed, a RoHS ban is no longer necessary.

BBP, DBP and DEHP phthalates will be assessed by the current additional RoHS substances study, but what they conclude and recommend depends on how the methodology is designed and whether industry puts up a robust case against restriction and lobbying from NGOs.

Scientifically, a ban of these is not necessarily needed. The EU carried out risk assessments of these a few years ago and from the results they banned these in toys only, presumably because a ban in products used by adults is not needed as they pose no risk. The consultants should review all research published since these risk assessments were completed before making a decision.

Directive Decoder

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Google reverses over offline Maps app Android Market Eyes On Android

Google Maps offline feature Thanks to ZDNet for highlighting an about-turn over the new version of the Google Mapps app. Offline browsing of maps will now be available via the app after all.

The company announced the new version on Wednesday – see Google reroutes new version of Google Maps app. As well as a new design, re-routing functionality and new reviews options, it also retired the offline maps feature. Well, this has provoked such a response that Google has moved very quickly to add a feature to let you select a map for offline viewing.

Spandas Lui writes:

“We’ve been happy to hear so many of you enjoying the interface and features of the new Google Maps app for Android, but we know some of you are missing an easy way to access maps offline,” Google said in a Google+ post. “That’s why our engineering team has been working around the clock to add a ‘Make this map area available offline’ card below the search box for easy access.”
Typing “OK maps” will also activate that feature. iOS users missed all the drama because their Maps update has yet to be released.

You can read the criticism and Google’s response.

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General Head-up displays can be big in cars, says analyst

11ihs A surprising new growth market is military-style head-up displays (HUD) which are finding their way into family cars with navigation and driver-assist functions.

Only 2% of automobiles sold in 2012 had HUDs, but sales of cars equipped with HUDs are predicted to rise to 9.1 million units in 2020, up from 1.2 million in 2012, according to a report from IHS Automotive.

Sales this year are forecast to climb 7% to 1.3 million units.

“Projecting an image that floats about 2.5 meters, or 7.5 feet, in front of motorists’ eyes, HUDs are the optimal display technology for cars—with studies having shown that this distance delivers the fastest response time for viewers,” said Ben Scott, technology solutions analyst for IHS Automotive.

“Apart from showing speed and warning signals, HUDs are perfectly suited for displaying navigation information or advanced driver assistance system (ADAS) data, allowing drivers to access critical material while keeping their eyes on the road,” said Scott.

Japan had the highest installation rate of car HUD systems in 2010, but Europe is expected by 2020 to take the lead.

The expectation is that a HUD can be combined with a vehicle’s GPS system giving the driver map, turning and even speed-limit and traffic-sign information on a car’s windscreen.

Other uses are possible as well, such as showing text messages from mobile phones or displaying track information from MP3 players.

In the future, HUDs may become large enough to fill the whole windscreen and present an “augmented reality” view to the driver, said the report.

ADAS features such as pedestrian warning, blind-spot detection or night vision could be overlaid to fill the whole windshield.

According to the report, HUD systems are not a new concept, as General Motors (GM) first introduced them in 1988. However, because of various problems with the technology, the light source used, and the optics, HUDs did not sell as well as anticipated.

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Business Altair Raises $25m

Oded Melamed - Altair Co-Founder and CEO Altair Semiconductor, the LTE chip-set specialist, has raised $25 million from existing backers: Bessemer, BRM, Giza, JVP and Pacific Technology.

Altair will use the capital partly to pay for wafers. “We intend to use the funds to support our customers as they ramp high volume production and deploy their products in the field,” says Oded Melamed, co-founder and CEO of Altair, pictured.

Altair produces low cost single-mode LTE chipsets. The cost of integrating LTE-only is substantially lower than LTE+3G.

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Power Novel voltage profile for 750W datacoms quarter brick

19jun13Ericsson 500 Ericsson has introduced an unusual output voltage strategy in a 750W quarter brick converter intended to feed point of load converters (PoLs) in datacoms equipment from 40 to 60V.

Called PKM4717NH, from 50-60V, the output is voltage regulated at 10.8V, delivering up to 70A.

From 40-50V, the output voltage if a fixed fraction of the input voltage – varying from 8.7 to 10.8V.

In fixed ratio mode, suppression techniques prevent input transients being passed to the output un-attenuated.

The firm is calling this mixed regulation ‘hybrid regulated ratio’ (HRR).

The power supply will also deliver 10.8V with inputs up to 72V with reduced performance.

10.8V is chosen during voltage regulation because: “Based on a bus-voltage optimisation study carried out by Ericsson, the optimal fixed voltage to limit board conduction losses during step-down conversion at the point-of-load is believed to be 10.8V in non-‘dynamic-bus-voltage’ applications,” said the firm. “This bus voltage is very common in datacom applications that no longer require the standard 12V supply to power disk drives. However, if this level is required for local sub-functions, then step-up POL converters can easily generate a 12V supply.”

Claimed power density is 31.12W/cm3 (508W/in3) and typical efficiency is 97.1% at 60% load.

The PKM-NH series uses the ‘two extra power pins’ footprint, although there is a version compatible with traditional five-pin intermediate bus converters. The quarter-brick format is 59.9×36.8×11.4mm.

A baseplate version is available for applications requiring additional cooling or a cold-wall attachment.

Input/output isolation is 2.25kV and protection includes: input overvoltage suppression, soft-start for high capacitance loads, delayed hiccup over-current protection, over-temperature protection, over-voltage and under-voltage lockout, and pre-bias start-up functionality.

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2013年7月10日星期三

Breakthrough study reveals biological basis for sensory processing disorders in kids

July 9, 2013 — Sensory processing disorders (SPD) are more prevalent in children than autism and as common as attention deficit hyperactivity disorder, yet it receives far less attention partly because it's never been recognized as a distinct disease.

In a groundbreaking new study from UC San Francisco, researchers have found that children affected with SPD have quantifiable differences in brain structure, for the first time showing a biological basis for the disease that sets it apart from other neurodevelopmental disorders.

One of the reasons SPD has been overlooked until now is that it often occurs in children who also have ADHD or autism, and the disorders have not been listed in the Diagnostic and Statistical Manual used by psychiatrists and psychologists.

"Until now, SPD hasn't had a known biological underpinning," said senior author Pratik Mukherjee, MD, PhD, a professor of radiology and biomedical imaging and bioengineering at UCSF. "Our findings point the way to establishing a biological basis for the disease that can be easily measured and used as a diagnostic tool," Mukherjee said.

The work is published in the open access online journal NeuroImage:Clinical.

'Out of Sync' Kids

Sensory processing disorders affect 5 to 16 percent of school-aged children.

Children with SPD struggle with how to process stimulation, which can cause a wide range of symptoms including hypersensitivity to sound, sight and touch, poor fine motor skills and easy distractibility. Some SPD children cannot tolerate the sound of a vacuum, while others can't hold a pencil or struggle with social interaction. Furthermore, a sound that one day is an irritant can the next day be sought out. The disease can be baffling for parents and has been a source of much controversy for clinicians, according to the researchers.

"Most people don't know how to support these kids because they don't fall into a traditional clinical group," said Elysa Marco, MD, who led the study along with postdoctoral fellow Julia Owen, PhD. Marco is a cognitive and behavioral child neurologist at UCSF Benioff Children's Hospital, ranked among the nation's best and one of California's top-ranked centers for neurology and other specialties, according to the 2013-2014 U.S. News & World Report Best Children's Hospitals survey.

"Sometimes they are called the 'out of sync' kids. Their language is good, but they seem to have trouble with just about everything else, especially emotional regulation and distraction. In the real world, they're just less able to process information efficiently, and they get left out and bullied," said Marco, who treats affected children in her cognitive and behavioral neurology clinic.

"If we can better understand these kids who are falling through the cracks, we will not only help a whole lot of families, but we will better understand sensory processing in general. This work is laying the foundation for expanding our research and clinical evaluation of children with a wide range of neurodevelopmental challenges - stretching beyond autism and ADHD," she said.

Imaging the Brain's White Matter

In the study, researchers used an advanced form of MRI called diffusion tensor imaging (DTI), which measures the microscopic movement of water molecules within the brain in order to give information about the brain's white matter tracts. DTI shows the direction of the white matter fibers and the integrity of the white matter. The brain's white matter is essential for perceiving, thinking and learning.

The study examined 16 boys, between the ages of eight and 11, with SPD but without a diagnosis of autism or prematurity, and compared the results with 24 typically developing boys who were matched for age, gender, right- or left-handedness and IQ. The patients' and control subjects' behaviors were first characterized using a parent report measure of sensory behavior called the Sensory Profile.

The imaging detected abnormal white matter tracts in the SPD subjects, primarily involving areas in the back of the brain, that serve as connections for the auditory, visual and somatosensory (tactile) systems involved in sensory processing, including their connections between the left and right halves of the brain.

"These are tracts that are emblematic of someone with problems with sensory processing," said Mukherjee. "More frontal anterior white matter tracts are typically involved in children with only ADHD or autistic spectrum disorders. The abnormalities we found are focused in a different region of the brain, indicating SPD may be neuroanatomically distinct."

The researchers found a strong correlation between the micro-structural abnormalities in the white matter of the posterior cerebral tracts focused on sensory processing and the auditory, multisensory and inattention scores reported by parents in the Sensory Profile. The strongest correlation was for auditory processing, with other correlations observed for multi-sensory integration, vision, tactile and inattention.

The abnormal microstructure of sensory white matter tracts shown by DTI in kids with SPD likely alters the timing of sensory transmission so that processing of sensory stimuli and integrating information across multiple senses becomes difficult or impossible.

"We are just at the beginning, because people didn't believe this existed," said Marco. "This is absolutely the first structural imaging comparison of kids with research diagnosed sensory processing disorder and typically developing kids. It shows it is a brain-based disorder and gives us a way to evaluate them in clinic."

Future studies need to be done, she said, to research the many children affected by sensory processing differences who have a known genetic disorder or brain injury related to prematurity.

The study's co-authors are Shivani Desai, BS, Emily Fourie, BS, Julia Harris, BS, and Susanna Hill, BS, all of UCSF, and Anne Arnett, MA, of the University of Denver.

The research was supported by the Wallace Research Foundation. The authors have reported that they have no conflicts of interest relevant to the contents of this paper to disclose.

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Study helps understand how nature maintains diversity

July 9, 2013 — By studying rapidly evolving bacteria as they diversify and compete under varying environmental conditions, researchers have shown that temporal niches are important to maintaining biodiversity in natural systems. The research is believed to be the first experimental demonstration of temporal niche dynamics promoting biodiversity over evolutionary time scales.

The temporal niches -- changes in environmental conditions that occur during specific periods of time -- promoted frequency-dependent selection within the bacterial communities and positive growth of new mutants. They played a vital role in allowing diversity among bacterial phenotypes to persist.

The research provides new insights into the factors that promote species coexistence and diversity in natural systems. Understanding the mechanisms governing the origin and maintenance of biodiversity is important to scientists studying the roles of both ecology and evolution in natural systems.

"This study provides the first experimental evidence showing the impact of temporal niche dynamics on biodiversity evolution," said Lin Jiang, co-author of the paper and an associate professor in the School of Biology at the Georgia Institute of Technology. "Our laboratory results in bacteria can potentially explain the diversity dynamics that have been observed for other organisms over evolutionary time."

The research, which was supported by the National Science Foundation, was scheduled to be published July 9 in the journal Nature Communications.

In experimental manipulation of the bacterium Pseudomonas fluorescens, the researchers showed that alternating environmental conditions in 24-hour cycles strongly influences biodiversity dynamics by helping to maintain closely-related phenotypes that might otherwise be lost to competition with a dominant phenotype. The experiment followed the bacteria through more than 200 generations over a period of nearly two weeks.

In the laboratory, Jiang and graduate student Jiaqi Tan established communities of the bacterium in test tubes called microcosms. In designing the experiments, they collaborated with Colleen Kelly, a senior research associate in the Department of Zoology at the University of Oxford.

"You begin with one phenotype, and within two days, you might have two or three different phenotypes," said Jiang. "The system can do this in a matter of days."

Through a 12-day experimental period, the researchers subjected one group of cultures to 24-hour periods in which they were alternately allowed to grow undisturbed and shaken vigorously. To control for the impact of starting conditions, cultures within those two groups were chosen to begin with a period of static growth, while others began with a period of shaken growth. Finally, groups of control cultures were grown under continuous shaking or continuous static conditions.

During the study, the researchers periodically measured the population sizes of each phenotype present in each culture. Cultures subjected to alternating shaking and static conditions produced the highest level of diversity among the closely-related bacteria, which is often studied because it diversifies so rapidly.

"Static conditions promoted diversification," Jiang explained. "But the shaking tended to maintain the diversity that had evolved. Both conditions were essential for high biodiversity."

In experiments, the ancestral bacterial phenotype, which is known as "smooth morph," quickly diversifies and generates two niche-specialists, known as "wrinkled spreader" and "fuzzy spreader." Those, in turn, diversify into additional phenotypes. Competition for oxygen in the microcosms in which the bacteria grow is believed to drive the diversification; shaking the microcosms changes the levels of oxygen available to each phenotype. Because different phenotype groups inhabit different sections of the container, the shaking eliminated the preferred niches of some phenotypes.

The diversification in the microcosms experiencing constant shaking was much slower than in static microcosms. In microcosms experiencing temporal niche dynamics -- the alternating shaking and non-shaking periods -- the diversity increased rapidly and was maintained longer than in the other environments. The researchers found that the two different temporal niche dynamics environments -- which differed only in their starting conditions -- both produced richer biodiversity than those environments without it.

While the diversification occurred rapidly over a period of four days, the decline in the number of phenotypes due to natural competition took longer. Some of the phenotypes were ultimately excluded through the competitive processes.

"Diversity typically increases with time, then plateaus," said Jiang. "Without temporal niche, diversity tends to decline. Temporal niche allows a greater diversity to be maintained over time than would be possible otherwise."

Though the study focused on rapidly diversifying bacteria, the researchers believe it may have broader implications. The general theory of temporal niche dynamics was developed with more complex organisms, such as plants and corals, in mind.

"The mechanisms that promote biodiversity, which we call frequency-dependent selection, are very common in species," said Tan. "As long as you have a strong intra-species competition within the populations, you are expected to see this frequency-dependent selection. Based on this most common mechanism that we find in this system, there are implications for other ecosystems."

For the future, the researchers would like to study the effects of combining spatial and temporal niches in evolution.

"From this experiment, we know that temporal niche can maintain biodiversity," said Tan. "Similarly, we want to manipulate spatial diversity to see if heterogeneity in the spatial scale can affect the maintenance of biodiversity."

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Neandertals shared speech and language with modern humans, study suggests

The Neandertals have fascinated both the academic world and the general public ever since their discovery almost 200 years ago. Initially thought to be subhuman brutes incapable of anything but the most primitive of grunts, they were a successful form of humanity inhabiting vast swathes of western Eurasia for several hundreds of thousands of years, during harsh ages and milder interglacial periods. We knew that they were our closest cousins, sharing a common ancestor with us around half a million years ago (probably Homo heidelbergensis), but it was unclear what their cognitive capacities were like, or why modern humans succeeded in replacing them after thousands of years of cohabitation. Recently, due to new palaeoanthropological and archaeological discoveries and the reassessment of older data, but especially to the availability of ancient DNA, we have started to realize that their fate was much more intertwined with ours and that, far from being slow brutes, their cognitive capacities and culture were comparable to ours.

Dediu and Levinson review all these strands of literature and argue that essentially modern language and speech are an ancient feature of our lineage dating back at least to the most recent ancestor we shared with the Neandertals and the Denisovans (another form of humanity known mostly from their genome). Their interpretation of the intrinsically ambiguous and scant evidence goes against the scenario usually assumed by most language scientists, namely that of a sudden and recent emergence of modernity, presumably due to a single -- or very few -- genetic mutations. This pushes back the origins of modern language by a factor of 10 from the often-cited 50 or so thousand years, to around a million years ago -- somewhere between the origins of our genus, Homo, some 1.8 million years ago, and the emergence of Homo heidelbergensis. This reassessment of the evidence goes against a saltationist scenario where a single catastrophic mutation in a single individual would suddenly give rise to language, and suggests that a gradual accumulation of biological and cultural innovations is much more plausible.

Interestingly, given that we know from the archaeological record and recent genetic data that the modern humans spreading out of Africa interacted both genetically and culturally with the Neandertals and Denisovans, then just as our bodies carry around some of their genes, maybe our languages preserve traces of their languages too. This would mean that at least some of the observed linguistic diversity is due to these ancient encounters, an idea testable by comparing the structural properties of the African and non-African languages, and by detailed computer simulations of language spread.

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