Domestic violence victims more likely to take up smoking

 

May 5, 2014

Columbia University's Mailman School of Public Health

One-third of women around the world have experienced physical or sexual violence at the hands of their intimate partners with consequences from post-traumatic stress disorder, anxiety, and depression, to sexually transmitted diseases, including HIV. Now, in a new study in 29 low-income and middle-income countries, researchers have identified yet another serious health risk associated with intimate partner violence: smoking.

One third of women around the world have experienced physical or sexual violence at the hands of their intimate partners with consequences from post-traumatic stress disorder, anxiety, and depression, to sexually transmitted diseases, including HIV. Now, in a new study in 29 low-income and middle-income countries, researchers at Columbia University's Mailman School of Public Health have identified yet another serious health risk associated with intimate partner violence (IPV): smoking.

The researchers examined the association between IPV and smoking among 231,892 women aged 15-29, using information collected in the Demographic and Health Surveys. Intimate partner violence is a serious problem in low- and middle-income countries. Reports of IPV in their study ranged from 9 to 63%. Employing a meta-analysis of country-level data that accounted for confounding factors like age, education, and household wealth, they found a 58% increased risk for smoking among the women who experienced IPV.

Women are thought to smoke tobacco to self-medicate to cope with stress from IPV. Many may be unaware of the serious health risks; tobacco kills half of its users, according to the World Health Organization.

"A recent WHO report on IPV recommended that there is a clear need to scale-up efforts to both prevent IPV from happening in the first place and to provide necessary services for women experiencing IPV," says senior author Peter A. Muennig, MD, MPH, associate professor of Health Policy and Management at Columbia's Mailman School of Public Health.

The study points to a specific need for investments to help IPV victims avoid tobacco, adds first author Rishi Caleyachetty, MBBS, PhD, an epidemiologist on a Fulbright Scholarship at Columbia's Mailman School of Public Health when he wrote the paper. "Information about the consequences of smoking, motivation to quit smoking and smoking-cessation treatments could be incorporated into IPV treatment by healthcare providers who routinely interact with IPV victims," Dr. Caleyachetty says.

Any intervention to lower smoking would very likely also improve their overall health. A 2013 report by the World Health Organization suggested a link between IPV and chronic conditions, including cardiovascular disease. "Smoking is associated with cardiovascular disease, and therefore may explain part of the association between exposure to IPV and cardiovascular disease," says Dr. Caleyachetty. "However, to my knowledge this has not been extensively examined."

The new study focused on low- and middle-income countries, where little research into the IPV-tobacco link has been done. However, the researchers say their results likely mean that the phenomenon is a global one. They cite among other papers, a 2008 study by Hee-Jin Jun et al that showed increased risk in American women.

IPV and smoking may have both been underreported in the current study, which could mean that the association between the two is stronger. A temporal relationship (e.g. IPV causes smoking) couldn't be determined since the data was collected at only one point in time. Research following a group of women over time would be necessary to strengthen the evidence.

Results appear online in the journal Global Public Health.

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Story Source:

The above story is based on materials provided by Columbia University's Mailman School of Public Health. Note: Materials may be edited for content and length.

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Journal Reference:

1. Rishi Caleyachetty, Justin B. Echouffo-Tcheugui, Rob Stephenson, Peter Muennig. Intimate partner violence and current tobacco smoking in low- to middle-income countries: Individual participant meta-analysis of 231,892 women of reproductive age. Global Public Health, 2014; 1 DOI: 10.1080/17441692.2014.905616

Caring for horses eases symptoms of dementia

 

A collaboration between The Ohio State University, an equine therapy center and an adult daycare center found that people with Alzheimer's were able to safely groom, feed and walk horses under supervision -- and the experience buoyed their mood and made them less likely to resist care or become upset later in the day.

The small pilot study, which appears in the journal Anthrozoös, suggests that equine therapy -- a treatment used today for children and teens who have emotional and developmental disorders -- could work for adults, too.

Holly Dabelko-Schoeny, associate professor of social work at Ohio State, said that equine therapy could supplement more common forms of animal therapy involving dogs or cats and provide a unique way to ease the symptoms of dementia without drugs.

"We wanted to test whether people with dementia could have positive interactions with horses, and we found that they can -- absolutely," Dabelko-Schoeny said. "The experience immediately lifted their mood, and we saw a connection to fewer incidents of negative behavior."

In addition to memory loss, people with Alzheimer's often experience personality changes, she explained. They can become depressed, withdrawn -- even aggressive. As researchers look for a way to prevent or treat the disease, today's therapies are becoming more focused on how to ease the emotional burden for patients and their families.

"Our focus is on the 'now.' What can we do to make them feel better and enjoy themselves right now? Even if they don't remember it later, how can we help in this moment?" she said.

At the adult daycare center, a National Church Residences Center for Senior Health in downtown Columbus, clients normally partake in crafts, exercise and other activities to manage their dementia. For this study, sixteen of the center's clients who had Alzheimer's -- nine women and seven men -- volunteered to break with their regular routine.

Once a week, eight of the clients would remain at the center and pursue other activities while the other eight took a bus trip to the Field of Dreams Equine Education Center in Blacklick, Ohio. There, they visited with horses under the supervision of National Church Residences caretakers, as well as faculty and students from the College of Social Work and the College of Veterinary Medicine at Ohio State.

The clients visited the farm once a week for a month, so that every participant had four visits total. They groomed and bathed the horses, walked them, and fed them buckets of grass.

The four horses were chosen for their gentle dispositions and calmness when facing new people and new situations. All participate in therapeutic riding programs for children and teens at Field of Dreams.

The researchers saw obvious signs that the clients enjoyed their time on the farm: they smiled, laughed and talked to the horses. Even those who normally acted withdrawn became fully engaged in the experience.

There was a clear improvement in dementia-related behavior among the clients who visited the farm. To track behavior, the researchers used a scoring system called the Modified Nursing Home Behavior Problem Scale, in which staff at the center rated the frequency with which the participants fidgeted, resisted care, became upset or lost their temper on days they went to the farm or stayed at the center.

On a scale of zero to four -- zero meaning the client never engaged in the problem behavior, and four meaning that they always engaged in it -- scores for the participants who went to the farm were an average of one point lower than the scores for their peers who stayed at the center. So clients who visited the farm were, on average, better behaved throughout that day.

Through mouth swabs, the researchers also measured the levels of the stress hormone cortisol in the patients' saliva. For participants with less severe dementia, the researchers saw a rise in cortisol levels, possibly due to the "good stress" of being in a new situation.

There was one unexpected benefit, though: the therapy boosted physical activity. The clients all had physical limitations, but when presented with the horses, they were inspired to push the boundaries of those limitations.

Some clients who never wanted to leave their wheelchair asked for help in standing up; others who rarely wanted to walk stood up and walked unassisted, though a caretaker was always there to help them balance. The clients grew more physically active on each visit to the farm.

Family members reported that their loved one remained engaged with the experience even after returning home. One commented to researchers that her mother "would never remember what she did at the center during the day, but she always remembered what she did at the farm."

While much study has gone into animal therapy as a treatment for dementia, that work has focused on dogs and cats, which can easily be brought to community-based care centers. This is the first study to examine equine therapy for the same population.

And while horses could possibly be brought to community centers for outdoor therapy, a situation where clients could periodically visit an equine therapy center might be the best option, Dabelko-Schoeny said. That way they get the full experience of being on the farm.

Gwendolen Lorch, assistant professor of veterinary clinical medicine at Ohio State and co-author of the study, agreed that the country setting may have made the therapy more effective.

"I think another positive influence for these clients was the environment. They found the quietness and smells of the country very relaxing and restful. This was in contrast to their normal day care environment and their intercity dwelling," Lorch said. "It is difficult to tell what factors made this successful, but we do know that it was most likely a combination of events."

This study was funded by a private donor who wanted Ohio State to study the effectiveness of equine therapy for dementia. Now that the study is over, some of the clients' families have elected to continue to visit the farm.

Bordeaux, France.

 

DHA during pregnancy does not appear to improve cognitive outcomes for children, study indicates

 

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Although there are recommendations for pregnant women to increase their intake of the omega-3 fatty acid docosahexaenoic acid (DHA) to improve fetal brain development, a randomized trial finds that prenatal DHA supplementation did not result in improved cognitive, problem-solving or language abilities for children at four years of age, according to the study in the May 7 issue of JAMA, a theme issue on child health. This issue is being released early to coincide with the Pediatric Academic Societies Annual Meeting.

Maria Makrides, B.Sc., B.N.D., Ph.D., of the South Australian Health and Medical Research Institute, Adelaide, Australia and colleagues conducted longer-term follow-up from a previously published study in which pregnant women received 800 mg/d of DHA or placebo. In the initial study, the researchers found that average cognitive, language, and motor scores did not differ between children at 18 months of age. For the follow-up study, outcomes were assessed at 4 years, a time point when any subtle effects on development should have emerged and can be more reliably assessed.

The majority (91.9 percent) of eligible families (DHA group, n = 313; control group, n = 333) participated in the follow-up. The authors found that measures of cognition, the ability to perform complex mental processing, language, and executive functioning (such as memory, reasoning, problem solving) did not differ significantly between groups.

"Our data do not support prenatal DHA supplementation to enhance early childhood development," the authors concluded.

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Story Source:

The above story is based on materials provided by The JAMA Network Journals. Note: Materials may be edited for content and length.

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Journal Reference:

1. Maria Makrides, Jacqueline F. Gould, Nicola R. Gawlik, Lisa N. Yelland, Lisa G. Smithers, Peter J. Anderson, Robert A. Gibson. Four-Year Follow-up of Children Born to Women in a Randomized Trial of Prenatal DHA Supplementation. JAMA, 2014; 311 (17): 1802 DOI: 10.1001/jama.2014.2194

Synthesized 'solar' jet fuel: Renewable kerosene from sunlight, water and carbon dioxide

 

May 3, 2014

ETH Zürich

With the first ever production of synthesized "solar" jet fuel, the EU-funded SOLAR-JET project has successfully demonstrated the entire production chain for renewable kerosene obtained directly from sunlight, water and carbon dioxide, therein potentially revolutionizing the future of aviation. This process has also the potential to produce any other type of fuel for transport applications, such as diesel, gasoline or pure hydrogen in a more sustainable way.

 

Artist's rendering of the functional principle.

With the first ever production of synthesized "solar" jet fuel, the EU-funded SOLAR-JET project has successfully demonstrated the entire production chain for renewable kerosene obtained directly from sunlight, water and carbon dioxide (CO₂), therein potentially revolutionizing the future of aviation. This process has also the potential to produce any other type of fuel for transport applications, such as diesel, gasoline or pure hydrogen in a more sustainable way.

Several notable research organizations from academia through to industry (ETH Zürich, Bauhaus Luftfahrt, Deutsches Zentrum für Luft- und Raumfahrt (DLR), ARTTIC and Shell Global Solutions) have explored a thermochemical pathway driven by concentrated solar energy. A new solar reactor technology has been pioneered to produce liquid hydrocarbon fuels suitable for more sustainable transportation.

"Increasing environmental and supply security issues are leading the aviation sector to seek alternative fuels which can be used interchangeably with today's jet fuel, so-called drop-in solutions," states Dr. Andreas Sizmann, the project coordinator at Bauhaus Luftfahrt. "With this first-ever proof-of-concept for 'solar' kerosene, the SOLAR-JET project has made a major step towards truly sustainable fuels with virtually unlimited feedstocks in the future.

The SOLAR-JET project demonstrated an innovative process technology using concentrated sunlight to convert carbon dioxide and water to a so-called synthesis gas (syngas). This is accomplished by means of a redox cycle with metal-oxide based materials at high temperatures. The syngas, a mixture of hydrogen and carbon monoxide, is finally converted into kerosene by using commercial Fischer-Tropsch technology.

"The solar reactor technology features enhanced radiative heat transfer and fast reaction kinetics, which are crucial for maximizing the solar-to-fuel energy conversion efficiency" said Professor Aldo Steinfeld, leading the fundamental research and development of the solar reactor at ETH Zürich.

Although the solar-driven redox cycle for syngas production is still at an early stage of development, the processing of syngas to kerosene is already being deployed by companies, including Shell, on a global scale. This combined approach has the potential to provide a secure, sustainable and scalable supply of renewable aviation fuel and more generally for transport applications. Moreover, Fischer-Tropsch derived kerosene is already approved for commercial aviation.

"This is potentially a very interesting novel pathway to liquid hydrocarbon fuels using focussed solar power," said Professor Hans Geerlings at Shell. "Although the individual steps of the process have previously been demonstrated at various scales, no attempt had been made previously to integrate the end-to-end system. We look forward to working with the project partners to drive forward research and development in the next phase of the project on such an ambitious emerging technology."

SOLAR-JET (Solar chemical reactor demonstration and Optimization for Long-term Availability of Renewable JET fuel) was launched in June 2011 and is receiving financial support from the European Union within the 7th Framework Programme for a duration of four years. In a first step, the technical feasibility of producing solar kerosene was proven. In the next phase of the project, the partners will optimise the solar reactor and assess the techno-economic potential of industrial scale implementation. The outcomes of SOLAR-JET will put Europe to the forefront of research, innovation and production of sustainable fuels directly from concentrated solar energy.

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Story Source:

The above story is based on materials provided by ETH Zürich. Note: Materials may be edited for content and length.

Taking the lead out of a promising solar cell: Environmentally friendly solar cell pushes forward the 'next big thing in photovoltaics'

 

May 4, 2014

Northwestern University

Researchers have developed a solar cell with good efficiency that uses tin instead of lead perovskite as the harvester of light. The low-cost, environmentally friendly solar cell can be made easily using 'bench' chemistry -- no fancy equipment or hazardous materials. Perovskite solar cells are being touted as the 'next big thing in photovoltaics.' Lead perovskite has achieved 15 percent efficiency, and tin perovskite should be able to match -- and possibly surpass -- that.

Solar panels (stock image). Northwestern University researchers are the first to develop a new solar cell with good efficiency that uses tin instead of lead perovskite as the harvester of light. The low-cost, environmentally friendly solar cell can be made easily using "bench" chemistry -- no fancy equipment or hazardous materials.

Northwestern University researchers are the first to develop a new solar cell with good efficiency that uses tin instead of lead perovskite as the harvester of light. The low-cost, environmentally friendly solar cell can be made easily using "bench" chemistry -- no fancy equipment or hazardous materials.

"This is a breakthrough in taking the lead out of a very promising type of solar cell, called a perovskite," said Mercouri G. Kanatzidis, an inorganic chemist with expertise in dealing with tin. "Tin is a very viable material, and we have shown the material does work as an efficient solar cell."

Kanatzidis, who led the research, is the Charles E. and Emma H. Morrison Professor of Chemistry in the Weinberg College of Arts and Sciences.

The new solar cell uses a structure called a perovskite but with tin instead of lead as the light-absorbing material. Lead perovskite has achieved 15 percent efficiency, and tin perovskite should be able to match -- and possibly surpass -- that. Perovskite solar cells are being touted as the "next big thing in photovoltaics" and have reenergized the field.

Kanatzidis developed, synthesized and analyzed the material. He then turned to Northwestern collaborator and nanoscientist Robert P. H. Chang to help him engineer a solar cell that worked well.

"Our tin-based perovskite layer acts as an efficient sunlight absorber that is sandwiched between two electric charge transport layers for conducting electricity to the outside world," said Chang, a professor of materials science and engineering at the McCormick School of Engineering and Applied Science.

Details of the lead-free solar cell will be published May 4 by the journal Nature Photonics. Kanatzidis and Chang are the two senior authors of the paper.

Their solid-state tin solar cell has an efficiency of just below 6 percent, which is a very good starting point, Kanatzidis said. Two things make the material special: it can absorb most of the visible light spectrum, and the perovskite salt can be dissolved, and it will reform upon solvent removal without heating.

"Other scientists will see what we have done and improve on our methods," Kanatzidis said. "There is no reason this new material can't reach an efficiency better than 15 percent, which is what the lead perovskite solar cell offers. Tin and lead are in the same group in the periodic table, so we expect similar results."

Perovskite solar cells have only been around -- and only in the lab -- since 2008. In 2012, Kanatzidis and Chang reported the new tin perovskite solar cell with promises of higher efficiency and lower fabrication costs while being environmentally safe.

"Solar energy is free and is the only energy that is sustainable forever," Kanatzidis said. "If we know how to harvest this energy in an efficient way we can raise our standard of living and help preserve the environment."

The solid-state tin solar cell is a sandwich of five layers, with each layer contributing something important. Being inorganic chemists, Kanatzidis and his postdoctoral fellows Feng Hao and Constantinos Stoumpos knew how to handle troublesome tin, specifically methylammonium tin iodide, which oxidizes when in contact with air.

The first layer is electrically conducting glass, which allows sunlight to enter the cell. Titanium dioxide is the next layer, deposited onto the glass. Together the two act as the electric front contact of the solar cell.

Next, the tin perovskite -- the light absorbing layer -- is deposited. This is done in a nitrogen glove box -- the bench chemistry is done in this protected environment to avoid oxidation.

On top of that is the hole transport layer, which is essential to close the electrical circuit and obtain a functional cell. This required Kanatzidis and his colleagues to find the right chemicals so as not to destroy the tin underneath. They determined what the best chemicals were -- a substituted pyridine molecule -- by understanding the reactivity of the perovskite structure. This layer also is deposited in the glove box. The solar cell is then sealed and can be taken out into the air.

A thin layer of gold caps off the solar-cell sandwich. This layer is the back contact electrode of the solar cell. The entire device, with all five layers, is about one to two microns thick.

The researchers then tested the device under simulated full sunlight and recorded a power conversion efficiency of 5.73 percent.

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Story Source:

The above story is based on materials provided by Northwestern University. Note: Materials may be edited for content and length.

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Journal Reference:

1. Feng Hao, Constantinos C. Stoumpos, Duyen Hanh Cao, Robert P. H. Chang, Mercouri G. Kanatzidis. Lead-free solid-state organic–inorganic halide perovskite solar cells. Nature Photonics, 2014; DOI: 10.1038/nphoton.2014.82

Bioinformatics approach helps researchers find new use for old drug

 

Developing and testing a new anti-cancer drug can cost billions of dollars and take many years of research. Finding an effective anti-cancer medication from the pool of drugs already approved for the treatment of other medical conditions could cut a considerable amount of time and money from the process.

Now, using a novel bioinformatics approach, a team led by investigators at Beth Israel Deaconess Medical Center (BIDMC) has found that the approved antimicrobial drug pentamidine may help in the treatment of patients with advanced kidney cancer. Described online in the journal Molecular Cancer Therapeutics, the discovery reveals how linking cancer gene expression patterns with drug activity might help advance cancer care.

"The strategy of repurposing drugs that are currently being used for other indications is of significant interest to the medical community as well as the pharmaceutical and biotech industries," says senior author Towia Libermann, PhD, Director of the Genomics, Proteomics, Bioinformatics and Systems Biology Center at BIDMC and Associate Professor of Medicine at Harvard Medical School. "Our results demonstrate that bioinformatics approaches involving the analysis and matching of cancer and drug gene signatures can indeed help us identify new candidate cancer therapeutics."

Renal cell cancer consists of multiple subtypes that are likely caused by different genetic mutations. Over the years, Libermann has been working to identify new disease markers and therapeutic targets through gene expression signatures of renal cell cancer that distinguish these different cancer subtypes from each other, as well as from healthy individuals. In this new paper, he and his colleagues were looking for drugs that might be effective against clear cell renal cancer, the most common and highly malignant subtype of kidney cancer. Although patients with early stage disease can often be successfully treated through surgery, up to 30 percent of patients with renal cell cancer present with advanced stages of disease at the time of their diagnosis.

To pursue this search, they made use of the Connectivity Map (C-MAP) database (http://www.broadinstitute.org/cmap), a collection of gene expression data from human cancer cells treated with hundreds of small molecule drugs.

"C-MAP uses pattern-matching algorithms to enable investigators to make connections between drugs, genes and diseases through common, but inverse, changes in gene expression," says Libermann. "It provided us with an exciting opportunity to use our renal cell cancer gene signatures and a new bioinformatics strategy to match kidney cancer gene expression profiles from individual patients with gene expression changes inducted by various commonly used drugs."

After identifying drugs that may reverse the gene expression changes associated with renal cell cancer, the investigators used assays to measure the effect of the selected drugs on cells. This led to the identification of a small number of FDA-approved drugs that induced cell death in multiple kidney cancer cell lines. The investigators then tested three of these drugs in an animal model of renal cell cancer and demonstrated that the antimicrobial agent pentamidine (primarily used for the treatment of pneumonia) reduced tumor growth and enhanced survival. Gene expression experiments using microarrays also identified the genes in renal cell cancer that were counteracted by pentamidine.

"One of the main challenges in treating cancer is the identification of the right drug for the right individual," explains first author Luiz Fernando Zerbini, PhD, of the International Center for Genetic Engineering and Biotechnology in Cape Town, South Africa, adding that this bioinformatics approach could be a particularly valuable lower-cost model in developing countries.

The authors say their next step will be to evaluate the potential of pentamidine in combination with the current standard-of-care therapies to treat kidney cancer. "Since the drugs we are evaluating are already FDA-approved, successful studies in preclinical animal models may enable us to rapidly move these drugs into clinical trials," adds Libermann.

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Story Source:

The above story is based on materials provided by Beth Israel Deaconess Medical Center. Note: Materials may be edited for content and length.

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Journal Reference:

1. L. F. Zerbini, M. K. Bhasin, J. F. de Vasconcellos, J. D. Paccez, X. Gu, A. L. Kung, T. A. Libermann. Computational repositioning and preclinical validation of pentamidine for renal cell cancer. Molecular Cancer Therapeutics, 2014; DOI: 10.1158/1535-7163.MCT-13-0750

World's smallest cardiac pacemaker implanted

 

In contrast to current pacemaker implant procedures, the Micra TPS implant does not require a surgical incision in the chest and the creation of a “pocket” under the skin.

The Minneapolis Heart Institute Foundation (MHIF) today announced its first implant of the world's smallest pacemaker: the Medtronic Micra™ Transcatheter Pacing System (TPS) in the Midwest. The device was implanted by Dr. Charles Gornick as part of the global pivotal clinical trial.

One-tenth the size of a conventional pacemaker, and comparable in size to a large vitamin, the Micra TPS pacemaker is delivered directly into the heart through a catheter inserted in the femoral vein. Once positioned, the pacemaker is securely attached to the heart wall and can be repositioned or retrieved if needed. The miniature device does not require the use of wires, known as "leads," to connect to the heart. Attached to the heart via small tines, the pacemaker delivers electrical impulses that pace the heart through an electrode at the end of the device.

This miniaturized technology is designed to provide patients with the advanced pacing technology of traditional pacemakers via a minimally invasive approach. We are proud that MHIF was selected among an elite group of institutions to take part in this clinical trial. If positive, the results of the trial could potentially benefit many people globally who receive pacemakers each year.

In contrast to current pacemaker implant procedures, the Micra TPS implant does not require a surgical incision in the chest and the creation of a "pocket" under the skin. This eliminates a potential source of complications, and any visible sign of the device. The Medtronic Micra TPS is an investigational device worldwide.

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Story Source:

The above story is based on materials provided by Minneapolis Heart Institute Foundation. Note: Materials may be edited for content and length.

Robot caregivers to help the elderly

 

Our life expectancy lengthens and members of the ‘silver generation’ make up an ever-larger proportion of the population. Can technologies help us in caring for ourselves, our older relatives and friends? Could we learn to live together with robots while being watched over by sensors? The people behind one EU research project certainly think so.

Our aging population is changing our society's dynamics and our economy. By 2050 there will only be two (instead of 4) Europeans of working age for each person over 65, and within a decade Europe will need to care for an estimated 84 million people with age-related health problems.

There is an upside to this challenge, though. Collectively, Europe's over-65's have a disposable income of over EUR 3,000 billion and a substantial part of this will be ploughed back into the caring economy. According to Stephen Von Rump, CEO of Giraff Technologies AB, the EU market for robots and other devices that help taking care of our elderly will reach EUR 13 billion by 2016, and at least EUR 14.5 billion in the U.S.

The demand for care services has many countries stretched to the limit. That's where technology can help. Says Mr Von Rump: 'Today there are an estimated 5 million homes in the EU where elderly residents are receiving formal care services, and 12 million homes globally. Those numbers would more than double if one includes elderly who don't receive formal care, but who (or whose families) would gladly pay for a telecare service if it would extend their time living at home.'

GIRAFF+ : A Robot Carer in your Home

GIRAFF+ is an EU research project to test how a network of sensors in cooperation with a robot can help older people live safer, more independent lives and enjoy social life from their home. The star of the system is Giraff, a telepresence robot. It moves around the person's home and enable them to interact with family, friends and healthcare professionals via videoconference. The GIRAFF+ system comes with sensors throughout the home and in wearable devices. These sensors are designed to detect activities like cooking, sleeping or watching television, but they also provide medical information, like blood pressure and body temperature. They allow the person's carers to remotely monitor their wellbeing and to check for falls. One of the users on the GIRAFF+ pilot, 94-year-old Lea Mina Ralli, wrote on her blog: 'People ask why I don't just live with my daughter, but she has grandchildren of her own and many new responsibilities. But with this valuable assistant that I call "Mr. Robin" I'm more relaxed about the years ahead, and so are my children and grandchildren.'

An Emerging Market in Caring Technology

'The system will be installed into 15 homes by the end of 2014,' says Amy Loutfi, the project coordinator. 'So far we have had six homes in Europe -- two homes each in Spain, Sweden and Italy -- where people have lived with the GIRAFF+ system. We are currently in the middle of the evaluations, but we see that various aspects of the system are appreciated differently by the different users. This goes to show that there is no 'one-size fits all' approach to technology at home, and that the latter should be both adaptable and tailored to user's needs.'

Current plans are to put the system in commercial production next year, based on an upfront fee and monthly subscriptions which would make it competitive when set alongside increasingly expensive full-time care.

Demonstration video: https://www.youtube.com/watch?v=9pTPrA9nH6E&feature=youtu.be

Terahertz imaging on the cheap: Fewer sensors required for high-resolution imaging systems

May 5, 2014

Massachusetts Institute of Technology

Terahertz imaging, which is already familiar from airport security checkpoints, has a number of other promising applications -- from explosives detection to collision avoidance in cars. Like sonar or radar, terahertz imaging produces an image by comparing measurements across an array of sensors. Those arrays have to be very dense, since the distance between sensors is proportional to wavelength. Scientists have now developed a technique that could reduce the number of sensors required for terahertz or millimeter-wave imaging by a factor of 10, or even 100, making them more practical.

Terahertz imaging, which is already familiar from airport security checkpoints, has a number of other promising applications -- from explosives detection to collision avoidance in cars. Like sonar or radar, terahertz imaging produces an image by comparing measurements across an array of sensors.

Terahertz imaging, which is already familiar from airport security checkpoints, has a number of other promising applications -- from explosives detection to collision avoidance in cars. Like sonar or radar, terahertz imaging produces an image by comparing measurements across an array of sensors. Those arrays have to be very dense, since the distance between sensors is proportional to wavelength.

In the latest issue of IEEE Transactions on Antennas and Propagation, researchers in MIT's Research Laboratory for Electronics describe a new technique that could reduce the number of sensors required for terahertz or millimeter-wave imaging by a factor of 10, or even 100, making them more practical. The technique could also have implications for the design of new, high-resolution radar and sonar systems.

In a digital camera, the lens focuses the incoming light so that light reflected by a small patch of the visual scene strikes a correspondingly small patch of the sensor array. In lower-frequency imaging systems, by contrast, an incoming wave -- whether electromagnetic or, in the case of sonar, acoustic -- strikes all of the sensors in the array. The system determines the origin and intensity of the wave by comparing its phase -- the alignment of its troughs and crests -- when it arrives at each of the sensors.

As long as the distance between sensors is no more than half the wavelength of the incoming wave, that calculation is fairly straightforward, a matter of inverting the sensors' measurements. But if the sensors are spaced farther than half a wavelength apart, the inversion will yield more than one possible solution. Those solutions will be spaced at regular angles around the sensor array, a phenomenon known as "spatial aliasing."

Narrowing the field

In most applications of lower-frequency imaging, however, any given circumference around the detector is usually sparsely populated. That's the phenomenon that the new system exploits.

"Think about a range around you, like five feet," says Gregory Wornell, the Sumitomo Electric Industries Professor in Engineering in MIT's Department of Electrical Engineering and Computer Science and a co-author on the new paper. "There's actually not that much at five feet around you. Or at 10 feet. Different parts of the scene are occupied at those different ranges, but at any given range, it's pretty sparse. Roughly speaking, the theory goes like this: If, say, 10 percent of the scene at a given range is occupied with objects, then you need only 10 percent of the full array to still be able to achieve full resolution."

The trick is to determine which 10 percent of the array to keep. Keeping every tenth sensor won't work: It's the regularity of the distances between sensors that leads to aliasing. Arbitrarily varying the distances between sensors would solve that problem, but it would also make inverting the sensors' measurements -- calculating the wave's source and intensity -- prohibitively complicated.

Regular irregularity

So Wornell and his co-authors -- James Krieger, a former student of Wornell's who is now at MIT's Lincoln Laboratory, and Yuval Kochman, a former postdoc who is now an assistant professor at the Hebrew University of Jerusalem -- instead prescribe a detector along which the sensors are distributed in pairs. The regular spacing between pairs of sensors ensures that the scene reconstruction can be calculated efficiently, but the distance from each sensor to the next remains irregular.

The researchers also developed an algorithm that determines the optimal pattern for the sensors' distribution. In essence, the algorithm maximizes the number of different distances between arbitrary pairs of sensors.

With his new colleagues at Lincoln Lab, Krieger has performed experiments at radar frequencies using a one-dimensional array of sensors deployed in a parking lot, which verified the predictions of the theory. Moreover, Wornell's description of the sparsity assumptions of the theory -- 10 percent occupation at a given distance means one-tenth the sensors -- applies to one-dimensional arrays. Many applications -- such as submarines' sonar systems -- instead use two-dimensional arrays, and in that case, the savings compound: One-tenth the sensors in each of two dimensions translates to one-hundredth the sensors in the complete array.

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Story Source:

The above story is based on materials provided by Massachusetts Institute of Technology. The original article was written by Larry Hardesty. Note: Materials may be edited for content and length.

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Journal Reference:

1. James D. Krieger, Yuval Kochman, Gregory W. Wornell. Multi-Coset Sparse Imaging Arrays. IEEE Transactions on Antennas and Propagation, 2014; 62 (4): 1701 DOI: 10.1109/TAP.2014.2299819