Nanotube Paint Can Spot Structural Defects and Alert Authorities Before Damage Occurs

By Rebecca Boyle 

Nano Paint Mohamed Saafi of the University of Strathclyde examines a piece of material coated with a new nano paint, which can detect structural damage when electrodes are attached. University of Strathclyde

A new paint made of power plant waste and carbon nanotubes can automatically detect structural faults, alerting authorities before damage occurs. It could be a cheaper, easier way to monitor facilities like bridges, mines and even wind turbines.
It’s made from aligned carbon nanotubes, which can carry an electric current, and fly ash, which is a byproduct of coal burning. The paint can be sprayed onto any surface, and electrodes are attached to it, according to developers at the University of Strathclyde in Glasgow. If the nanotubes bend, their conductivity will change, which will be detected by the electrodes. Small wireless transmitters placed throughout the structure would receive data from the electrodes. If they detect a change in conductivity, this would be considered a sign of a defect in the structure. Then the system could conceivably alert the company or government body responsible for maintaining said structure.

Technology, Rebecca Boyle, bridges, carbon nanotubes, coal, coal plants, structural analysis, structural engineering, tunnels, wind turbines

This would be much cheaper and simpler than current monitoring methods, Strathclyde scientists said — currently, wind turbine foundations are inspected visually, and bridges and tunnels only have monitoring networks in certain areas, not throughout the whole structure. Early defect detection could be cheaper to repair, not to mention safer. A network of electrode-embedded nanotubes doesn’t sound inexpensive, but the researchers say it would be cheap — one percent the cost of alternative inspection methods — in part because of the fly ash component. Fly ash is a byproduct of coal combustion and it’s generally stored at power plants and landfills or it’s recycled. The nanotube paint could be one new use for it. It also lends the paint some added durability, which means it could last in a wide range of environmental conditions.
For now, the electrode transmitters would be powered by batteries, but other designs could incorporate solar panels, piezoelectrics or other energy-harvesting technology, the researchers say. Strathclyde Ph.D candidate David McGahon and civil engineering professor Mohamed Saafi have built a prototype and it was shown to be effective, according to a Strathclyde news release. They plan to carry out larger-scale tests in Glasgow in the future.
[via Science Daily]

Three Habits Which Will Ruin Your Chances Of Being Hired

Are you struggling to find a job and unsure of the reason why? Perhaps, you are using some archaic habits which are being looked down upon by potential employers. Stay current, with the best practices for job searching and ensure that you are on the top of every employers list!

“Is it still correct to use ‘Dear Sir or Madam’ in a cover letter?” a reader asked in an e-mail.

“That isn’t such a great idea,” I wrote back. “No one uses ‘Dear Sir or Madam’ anymore, unless they’re actually writing to a madam, such as Heidi Fleiss.” I’m not sure my e-mail correspondent caught the joke.

It’s not that using out-of-date job-search approaches brands you as older. Rather, it’s that using no-longer-in-fashion job search techniques marks you as out of touch.

Employers pay us, in part, to be aware of trends and phenomena that affect the workplace. Working people (and job-seekers) should follow the news, keep a bead on our changing world, and stay abreast of changes in business, technology, politics, and cultural shifts. That isn’t an unreasonable expectation. If a job-seeker isn’t curious and perceptive enough to notice that the last time he saw “Dear Sir or Madam” on a letter was around the time Chevy Chase impersonated Gerald Ford falling down the stairs, how will he notice what’s changing in his field?

Here are three formerly useful, now dangerous job-search approaches that hark back to an earlier age. Get them out of your job-search repertoire, pronto.

1. Dedicated Résumé Paper and Envelopes. Don’t use nubbly beige or pink or stone-greyrésumé paper, or any other kind of special paper or matching envelopes, in your job search. Dedicated-use résumé paper is a 1980s artifact. Most of your résumés will reach employers electronically, in which case the employer will print it out. For résumés you print on your own, use plain white bond paper. (If you want to use a heavier stock than usual, do it.) Keep résumé formatting simple. You don’t need horizontal lines or curlicues, unless you are yourself a creative person, in which case you can go hog-wild with artistic expression. What matters in your résumé is its content. You won’t win any points with a résumé or cover letter on fancy paper that whispers, “I have a stack of Christopher Cross cassettes in my car.”

2. Creaky Cover Letter Language. When I read “Dear Sir or Madam,” I instantly get a picture of a person wearing white gloves and carrying tiny mother-of-pearl opera glasses in her handbag. Don’t get me wrong—I have opera glasses and I wish white gloves were still in style. They’re not. Never use “Dear Sir or Madam”—or its cousin, “To Whom It May Concern”—in a cover letter for the same reason. In 2012, companies are porous. We can find our hiring manager’s name in two seconds using LinkedIn. We are obliged to try: Correspondence that begins “To Whom It May Concern” means death to a job search. “Dear Hiring Manager” is just as bad. Find the name of the relevant person or lob a résumé into the Black Hole and skip the cover letter altogether.

3. Here’s Why You Should Hire Me. People get hired when a hiring manager believes, intellectually and emotionally, that the person sitting in front of him or her can do the job. It isn’t a linear process. That’s not great news to people who believe that power comes from their degrees and certifications because those folks are often more comfortable pushing their skills out in front of them than sitting and talking with a manager in a way that inspires confidence and trust. But tons of job-search books and articles nonetheless encourage job-seekers to grovel and beg, as though any manager has ever been convinced of an applicant’s heft and power by hearing the applicant say: “Please hire me—I’ll do anything you want!”

Groveling doesn’t work, which is why compiling and mailing goofy lists such as “here are 10 reasons you should hire me” are terrible things to do. When we write a post-interview thank-you note or e-mail, we should use it to continue the substantive conversation that started during a job interview, not to mewl and beg for a job. We never, ever want to construct lists of reasons an employer should hire us. We won’t convince anyone of our value that way. If the reasons to hire don’t come through in an interview, you’ve already missed the boat.

Get more great tips from Yahoo Finance!

From millions of tasks to thousands of jobs: Bringing digital work to developing countries

Submitted by Vili Lehdonvirta

Every country in the world has probably benefited in some way from the unprecedented access to knowledge and services brought about by the digital revolution. But producing knowledge banks and services has so far been a predominately rich-country business. The world’s poorest countries have generally not been able to participate in the production side of the digital economy and share in its rewards. This is changing, however, and an infoDev-led online challenge called m2Work is helping to drive the change. Job creation continues to be a priority of the World Bank and the m2Work competition shows an innovative approach to addressing this challenge.

As the digital economy grows, it increasingly gives rise to work that is “born digital” – that is, new work that arises out of the possibilities and needs of the digital world. This phenomenon is distinct from how conventional jobs are increasingly digitized in the sense that they make heavy use of information and communication technologies. Most born-digital work represents new work that doesn’t directly compete with old occupations.

For example, hundreds of thousands of people around the world earn income from tasks like moderating images posted by users to an online community, categorizing products on an e-commerce site, and transcribing digital video clips to make them more searchable. Because these tasks are completely digital, they can be physically carried out anywhere a computer can be connected to the Internet.

A recent trend is that demand for such digital blue-collar work is satisfied through so-called “crowdsourcing” and “microsourcing” models. This means that instead of a company hiring a staffer or a contractor to carry out a job, the job is broken down into individual tasks and distributed to a large pool of workers over a digital network.

For example, many companies post their tasks on Amazon Mechanical Turk (AMT), a digital labor marketplace. At any given time, AMT carries around 200,000 micro-tasks, each worth anywhere from a few cents to several dollars. Anyone wishing to earn this money can simply point their web browser to AMT and follow the instructions. Microwork is inclusive in the sense that gender, disability and other personal characteristics do not play a role in digital labor marketplaces.

A 2011 report commissioned by infoDev (a partnership program within the World Bank’s Finance and Private Sector Development Network), titled Knowledge Map of the Virtual Economy, assessed the development potential of digital microwork. According to the report, microwork has several features that make it particularly accessible to people in developing countries. Most tasks require few skills or qualifications, as they rely on the fact that humans are inherently better than computers in tasks like image recognition and natural language processing. Microwork is not connected to one particular spot; a web browser is enough. Low labor cost moreover gives a competitive advantage to workers from developing countries.

Many microworkers are indeed located in the developing world. According to one survey, 34 percent of workers on AMT are from India. Two other microwork distributors, Samasource and MobileWorks, have workers in countries such as Kenya, Pakistan and the Philippines. Workers access the tasks from computers in Internet cafés and offices, and earn income in the form of cash, bank deposits and gift cards. In these low- to medium-developed countries, digital microwork seems to be having a real economic impact.

Low-income countries have the most to gain from tapping into this source of digital export income. However, their ability to do so is limited by their digital infrastructure: the availability of computers and Internet cafés from which to access digital labor markets.

Meanwhile, even the most underprivileged people in the world increasingly have access to mobile phones. There are close to 6 billion mobile phone subscriptions in the world, and over half a billion in India alone. In 2011, mobile phone penetration reached almost 80 percent in the developing world.

To help tap into that high level of mobile access, infoDev and Nokia’s IdeasProject have organized the m2Work online challenge, with funding and support from UKaid and the government of Finland. The challenge aims to identify problems and needs that could be addressed by microworkers who use mobile phones – enabling the bottom billions of the economic pyramid to access the digital economy, and enabling the rest of the world to benefit from their intelligence.

A high-level jury consisting of among others the World Bank’s Chief Information Officer, Ms. Shelley Leibowitz, representatives of Nokia and the wider technology sector, will review the submissions. The best ideas will be awarded with individual cash prizes of up to $20,000. Furthermore, infoDev will use its vast network of Mobile Applications Labs (mLabs) and business incubators to help the winning entrepreneurs every step of the way, guiding it from seed-stage idea to a thriving start-up that creates sustainable jobs.

From earlier experiences in other industries, we know that new blue-collar jobs do not necessarily translate into lasting economic and social development, if the jobs build no long-term capacities. But the Virtual Economy report shows that digital labor can be capacity-building, by showcasing earlier examples of born-digital work.  In the end, the m2Work challenge wants to spark a goal-oriented, global discussion about sustainable mobile microwork under the motto of “From millions of tasks to thousands of jobs”.

Brain capacity limits exponential online data growth

Scientists have found that the capacity of the human brain to process and record information - and not economic constraints - may constitute the dominant limiting factor for the overall growth of globally stored information. These findings have just been published in an article in EPJ B by Claudius Gros and colleagues from the Institute for Theoretical Physics at Goethe University Frankfurt in Germany.

The authors first looked at the distribution of 633 public internet files by plotting the number of videos, audio and image files against the size of the files. They gathered files which were produced by humans or intended for human use with the spider file search engine Findfiles.net. They chose to focus on files which are hosted on domains pointing from the online encyclopaedia Wikipedia and the open web directory dmoz.

Assuming that economic costs for data production are proportional to the amount of data produced, these costs should be driving the generation of information exponentially. However, the authors found that, in fact, economic costs were not the limiting factors for data production. The absence of exponential tails for the graph representing the number of files indicates this conclusion.

They found that underlying neurophysiological processes influence the brain's ability to handle information. For example, when a person produces an image and attributes a subjective value to it, for example, a given resolution, he or she is influenced by his or her perception of the quality of that image. Their perception of the amount of information gained when increasing the resolution of a low-quality image is substantially higher than when increasing the resolution of a high-quality photo by the same degree. This relation is known as the Weber-Fechner law.

The authors observed that file-size distributions obey this Weber-Fechner law. This means that the total amount of information cannot grow faster than our ability to digest or handle it.

More information: Gros C., Kaczor G., Marković D., (2012) Neuropsychological constraints to human data production on a global scale, European Physical Journal B (EPJ B) 85: 28, DOI 10.1140/epjb/e2011-20581-3

Provided by Springer

"Brain capacity limits exponential online data growth." February 1st, 2012. http://www.physorg.com/news/2012-02-brain-capacity-limits-exponential-online.html

Posted by
Robert Karl Stonjek

Men more likely to have an accurate memory of unpleasant experiences

A woman's memory of an experience is less likely to be accurate than a man's if it was unpleasant and emotionally provocative, according to research undertaken by University of Montreal researchers at Louis-H Lafontaine Hospital.
"Very few studies have looked at how 'valence' and 'arousal' affect memories independently of each other, that is to say, how attractive or repulsive we find an experience and how emotionally provocative it is," said corresponding author Dr. Marc Lavoie, of the university's Department of Psychiatry and the hospital's Fernand-Seguin Research Center. "Our test relied on photos – we found firstly that highly arousing pictures blur women's capacity to determine whether they've seen it before, and secondly that women have a clearer memory of attractive experiences than men. Arousal has an enhancing effect on the memory of men however, as does 'low valence' or unpleasantness."
Participants were shown a variety of images on a computer screen that fell into four categories: "low-valence and low-arousal" such as scenes of babies crying, "low-valence and high-arousal," for example, war photos, "high-valence and low-arousal," which included pictures of kittens, and finally, erotic photos for the "high-valence and high-arousal" group. They were then shown a second round of photos that included the same images as the first round and some new ones. The participants had to push buttons to indicate whether they had already seen it or if it was new, and the speed and accuracy with which they responded enabled the researchers to gauge which factors had the most influence. They were also connected to EEG, a system for measuring the brain's neuron activity, which enabled the researchers to see how their brain was working as they completed the task.
"Interestingly, the scans revealed more activity in the right hemisphere of women's brains for the recognition of pleasant pictures – the opposite of what we witnessed in men" Lavoie said. "This challenges earlier studies using unpleasant pictures that revealed more activity in the left hemisphere for women and in the right hemisphere for men. Our findings demonstrate the complexity of emotional memory and underscore the importance of taking valence, arousal, and sex differences into account when examining brain activity."
The study was published online by the International Journal of Psychophysiology on January 18, 2012, and the research received funding from the Natural Sciences and Engineering Research Council of Canada through a discovery grant to Dr Lavoie and a summer student internship to Emma Glaser. Dr. Marc Lavoie is affiliated with the Fernand-Seguin Research Centre at Louis.-H. Lafontaine Hospital in Montreal and with the Department of Psychiatry at the University of Montreal. The University of Montreal is officially known as Université de Montréal.
More information: Emma Glaser, Adrianna Mendrek, Martine Germain, Nadia Lakis, Marc E. Lavoie, Sex differences in memory of emotional images: A behavioral and electrophysiological investigation, International Journal of Psychophysiology, Available online 18 January 2012, ISSN 0167-8760, doi:10.1016/j.ijpsycho.2012.01.007
Provided by University of Montreal

"Men more likely to have an accurate memory of unpleasant experiences." February 1st, 2012. http://medicalxpress.com/news/2012-02-men-accurate-memory-unpleasant.html

Posted by
Robert Karl Stonjek

THE SECRET TO A HAPPY MARRIED LIFE.

Once I was asked by my friend,

"What is the secret behind your happy married life?"
 
I said,

"You should share responsibilities with due love and respect each other.

Then absolutely there will be no problems."
   
He asked,

"Can you explain?"
 
I said,

"In my house, I take decisions on bigger issues where as my wife decides on smaller issues.

We do not interfere in each other's decisions."
 
Still not convinced, the friend asked me,

"Give me some examples".
 
I said,

"Smaller issues like,

Which car we should buy,

How much amount to save,

When to visit the super market,

When to go on vacation,

Which sofa,

Air conditioner,

Refrigerator,

Monthly expenses,

Whether to keep a maid or not etc.

Are all decided by my wife.

I just agree to it "
 
He asked,

"Then, what is your role?"
 
I said,

"My decisions are only for very big issues.

Like whether America should attack Iran,

Whether Britain should lift sanctions over Zimbabwe,

Whether to widen the Sri Lankan economy,

Whether Sanath Jayasuriya  should retire from cricket etc., etc. and

Do you know, my wife, NEVER, objects to any of these decisions".

Nothing is more precious than peace...

Heart failure is associated with loss of brain cells and a decline in mental processes

Australian researchers have found evidence that heart failure is associated with a decline in people's mental processes and a loss of grey matter in the brain. These changes can make it more difficult for heart failure (HF) patients to remember and carry out instructions such as taking the correct medication at the right times.

The authors of the study, which is published online today in the European Heart Journal, say: "Our results are consistent with the observation that people with HF have trouble adhering to complex self-care advice, and suggest that simpler approaches to self-management may be required".

Professor Osvaldo Almeida, who is Professor and Winthrop Chair of Geriatric Psychiatry at the University of Western Australia and Director of Research at the Western Australia Institute for Health and Ageing in Perth, and his colleagues carried out cognitive tests on 35 patients with HF, 56 patients with ischaemic heart disease (IHD), which can often but not always accompany HF, and 64 healthy people without HF or IHD. They also used magnetic resonance imaging (MRI) to assess differences in the volume of grey matter in different parts of the brain.

Results showed that patients with HF had worse immediate and long-term memory and reaction speeds (psychomotor speed) than the healthy controls. Heart failure was also associated with changes in brain regions that are important for mentally demanding cognitive and emotional processing.

"What we found in this study is that both IHD and HF are associated with a loss of cells in certain brain regions that are important for the modulation of emotions and mental activity – such a loss is more pronounced in people with HF, but can also be seen in people with IHD without HF," explained Prof Almeida. "Similarly, people with IHD and HF show subtle deficits in cognitive abilities compared with controls without either IHD or HF, and again those deficits are more pronounced in people with HF. Our study was not sufficiently large to show with certainty that the cognitive performance of participants with HF was worse than that of participants with IHD, although both showed deficits compared with controls."

The regions of the brain that showed loss of grey matter are believed to be important for memory, reasoning and planning. "There is evidence that they optimise performance in complex tasks that require 'mental effort'. Consequently, loss of brain cells in these regions may affect a person's performance in a number of different areas, such as memory, behaviour modification, inhibition, both emotional and cognitive, and organisation," said Prof Almeida.

"Our findings indicate that diseases that affect the heart affect the brain as well, and that the changes in organ function and blood circulation associated with HF seem to compound these effects in the brain. For these reasons, primary and secondary prevention are essential to minimise the impact of heart disease on brain structure and function. They are also consistent with the possibility that patients with HF may have trouble following complex management strategies, and, therefore, treatment messages should be simple and clear. Health professionals and patients need to be aware that problems caused by heart disease are not limited to the heart."

The authors write: "As far as we are aware, this is the first study that included an additional IHD control group that shares common risk factors with HF, which allowed us to show that the cognitive losses may be a non-specific consequence of increasing cardiovascular disease burden. Moreover, our analyses revealed that these subtle deficits . . . cannot be explained by impaired left ventricular ejection fraction, prevalent comorbid conditions, or biochemical markers.

"The acquisition of structural brain images allowed us to examine the impact of both HF and IHD on cerebral GM [grey matter] and to show that the people with HF display more widespread and extensive brain changes than adults with IHD."

Prof Almeida and his colleagues say that larger and longer studies are need to clarify the physiological pathways by which HF could lead to loss of brain cells and worse mental processes, and to see whether the changes are progressive; for instance, they are investigating whether grey matter loss increases and the cognitive problems become worse over time. They also want to examine whether HF patients could benefit from cognitive rehabilitation or stimulation.

More information: "Cognitive and brain changes associated with ischaemic heart disease and heart failure". European Heart Journal.doi:10.1093/eurheartj/ehr467

 

Provided by European Society of Cardiology

"Heart failure is associated with loss of brain cells and a decline in mental processes." January 31st, 2012. http://medicalxpress.com/news/2012-01-heart-failure-loss-brain-cells.html

 

Posted by
Robert Karl Stonjek

'Life and activity monitor' provides portable, constant recording of vital signs

This small device, only about two inches wide, can monitor vital signs while being worn outside the body. (Photo courtesy of Oregon State University)

Researchers have developed a type of wearable, non-invasive electronic device that can monitor vital signs such as heart rate and respiration at the same time it records a person's activity level, opening new opportunities for biomedical research, diagnostics and patient care.

The device is just two inches wide, comfortable, does not have to be in direct contact with the skin and can operate for a week without needing to be recharged. Data can then be downloaded and assessed for whatever medical or research need is being addressed.

The technology has been reported at a professional conference, and research is continuing to make it even smaller and less costly.

"When this technology becomes more miniaturized and so low-cost that it could almost be disposable, it will see more widespread adoption," said Patrick Chiang, an assistant professor of computer engineering at Oregon State University. "It's already been used in one clinical research study on the effects of micronutrients on aging, and monitoring of this type should have an important future role in medicine."

Vital sign data can be relayed by the small electronic device worn on the body. (Image courtesy of Oregon State University)

Called a "life and activity monitor," the system uses different sensors to detect heart rate, respiration, movement and similar vital signs. It will provide doctors, researchers and clinicians a continuous flow of data over time, reduce the need for more frequent office visits, and ultimately provide better care at lower cost.

The system was developed by scientists and engineers at Oregon State University and the University of California at San Diego.

Final designs of the technology may be as small as a disposable bandage, researchers say.

Provided by Oregon State University

"'Life and activity monitor' provides portable, constant recording of vital signs." February 1st, 2012.http://medicalxpress.com/news/2012-02-life-portable-constant-vital.html

 

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Robert Karl Stonjek

How antipsychotic medications cause metabolic side effects such as obesity and diabetes

In 2008, roughly 14.3 million Americans were taking antipsychotics—typically prescribed for bipolar disorder, schizophrenia, or a number of other behavioral disorders—making them among the most prescribed drugs in the U.S. Almost all of these medications are known to cause the metabolic side effects of obesity and diabetes, leaving patients with a difficult choice between improving their mental health and damaging their physical health. In a paper published January 31 in the journalMolecular Psychiatry, researchers at Sanford-Burnham Medical Research Institute (Sanford-Burnham) reveal how antipsychotic drugs interfere with normal metabolism by activating a protein called SMAD3, an important part of the transforming growth factor beta (TGFbeta) pathway.

The TGFbeta pathway is a cellular mechanism that regulates many biological processes, including cell growth, inflammation, and insulin signaling. In this study, all antipsychotics that cause metabolic side effects activated SMAD3, while antipsychotics free from these side effects did not. What's more, SMAD3 activation by antipsychotics was completely independent from their neurological effects, raising the possibility that antipsychotics could be designed that retain beneficial therapeutic effects in the brain, but lack the negative metabolic side effects.

"We now believe that many antipsychotics cause obesity and diabetes because they trigger the TGFbeta pathway. Of all the drugs we tested, the only two that didn't activate the pathway were the ones that are known not to cause metabolic side effects," said Fred Levine, M.D., Ph.D., director of the Sanford Children's Health Research Center at Sanford-Burnham and senior author of the study.

In a previous study aimed at developing new insights into diabetes, Dr. Levine and his team used Sanford-Burnham's high-throughput screening capabilities to search a collection of known drugs for those that alter the body's ability to generate insulin, the pancreatic hormone that helps regulate glucose. That's when they first noticed that many antipsychotics alter the activity of the insulin gene. In this current study, the researchers set out to connect the dots between antipsychotics and insulin. In doing so, experiments in laboratory cell-lines showed that antipsychotics known to cause metabolic side effects also activated the TGFbeta pathway—a mechanism that controls many cellular functions, including the production of insulin—while the drugs without these side effects did not.

Wondering whether their initial laboratory observations were relevant to the human experience, the researchers reanalyzed previously published gene expression patterns in brain tissue from schizophrenic patients treated with antipsychotics. What they found supported their earlier findings—TGFbeta signaling was activated only in those patients receiving antipsychotic treatment. Looking further, they found that the extent to which each antipsychotic drug activated the TGFbeta pathway in human brains correlated very closely with the extent to which those same drugs activated SMAD3 and affected the insulin promoter in their cell culture experiments.

The TGFbeta pathway also plays an important role in metabolic disease in people who don't take antipsychotic medications. "It's known that people who have elevated TGFbeta levels are more prone to diabetes. So having a dysregulated TGFbeta pathway—whether caused by antipsychotics or through some other mechanism—is clearly a very bad thing," said Dr. Levine. "The fact that antipsychotics activate this pathway should be a big concern to pharmaceutical companies. We hope this new information will lead to the development of improved drugs."

Provided by Sanford-Burnham Medical Research Institute

"How antipsychotic medications cause metabolic side effects such as obesity and diabetes." February 1st, 2012.http://medicalxpress.com/news/2012-02-antipsychotic-medications-metabolic-side-effects.html

 

Posted by
Robert Karl Stonjek

Researchers pinpoint genetic connection to traumatic experience

Rutgers scientists have uncovered genetic clues as to why some mice no longer in danger are still fearful while others are resilient to traumatic experiences – knowledge that could help those suffering with crippling anxiety and PTSD.

"Our work with mice demonstrates how genes play a role in developing and extinguishing pathological fear like Post Traumatic Stress Disorder," says Gleb Shumyatsky, an associate professor in the Department of Genetics in the School of Arts and Sciences. "It is clear that previous life experiences are not the only cause of PTSD – genetic predispositions may make some people more sensitive and others more resilient to PTSD."

Since humans and animals register fear in the brain similarly, the discovery being reported today in the journal PLoS ONE, is an important step to understanding how genes work in the brain to control learning and memory as well as reactions to fearful and traumatic experiences.

In the study, mice bred missing either one of the two fear memory-related genes were trained to be afraid of the cage and a tone associated with a mild shock. Next, by repeatedly putting the mice in the training cage or presenting them with the tone – but now without the shock – the scientists taught them not to be afraid, a process called fear memory extinction. When extinction was performed using the fearful context, a training cage, the knockout mice behaved normally, similar to wild type control mice.

These same mutant mice acted quite differently, however, when they heard a quiet, fear-evoking tone that had previously been followed by the same shock. Mice bred without the gastrin-related peptide receptor (GRPR) gene were more fearful of the tone and froze up more often than normal mice, despite no longer being in danger of receiving a shock. By contrast, mice bred without the stathmin gene forgot that they had been afraid of the dangerous tones and stopped freezing.

Next, the scientists analyzed the neural activities of portions of the brain that deal with fear and anxiety in humans – the amygdala, hippocampus, and medial prefrontal cortex. What they discovered: Genetic evidence of a connection between the amygdala – the portion of the brain where unconscious fears are stored – and the prefrontal cortex, the area that enables animals and humans to inhibit excessive fear to better react to potential danger.

The "fearless" stathmin-deficient mice exhibited an increase in brain activity in the prefrontal cortex and a decrease in the amygdala. The opposite occurred in the timid, GRPR deficient mice that were overly afraid in spite of the fact that they were no longer in danger.

Shumyatsky says scientists need to continue identifying molecules involved in the neural circuits of the brain responsible for specific memories and behaviors in order to develop psychotherapeutic, pharmacological and genetic therapies to treat disabling anxiety disorders like PTSD which is estimated to affect 30 percent of combat veterans.

"The research suggests that there are different types of PTSD and that different medical treatments could be applied to treat the cue-related versus the context-related PTSD symptoms, Shumyatsky says.

Provided by Rutgers University

"Researchers pinpoint genetic connection to traumatic experience." February 1st, 2012. http://medicalxpress.com/news/2012-02-genetic-traumatic.html

 

Posted by
Robert Karl Stonjek

Blood test accurately distinguishes depressed patients from healthy controls

The initial assessment of a blood test to help diagnose major depressive disorder indicates it may become a useful clinical tool. In a paper published in the journal Molecular Psychiatry, a team including Massachusetts General Hospital (MGH) researchers reports that a test analyzing levels of nine biomarkers accurately distinguished patients diagnosed with depression from control participants without significant false-positive results.

"Traditionally, diagnosis of major depression and other mental disorders has been made based on patients' reported symptoms, but the accuracy of that process varies a great deal, often depending on the experience and resources of the clinician conducting the assessment," says George Papakostas, MD, of the MGH Department of Psychiatry, lead and corresponding author of the report. "Adding an objective biological test could improve diagnostic accuracy and may also help us track individual patients' response to treatment."

The study authors note that previous efforts to develop tests based on a single blood or urinary biomarker did not produce results of sufficient sensitivity, the ability to detect the tested-for condition, or specificity, the ability to rule out that condition. "The biology of depression suggests that a highly complex series of interactions exists between the brain and biomarkers in the peripheral circulation," says study co-author John Bilello, PhD, chief scientific officer of Ridge Diagnostics (http://www.ridgedx.com

 

), which sponsored the current study. "Given the complexity and variability of these types of disorders and the associated biomarkers in an individual, it is easy to understand why approaches measuring a single factor would not have sufficient clinical utility."

The test developed by Ridge Diagnostics measures levels of nine biomarkers associated with factors such as inflammation, the development and maintenance of neurons, and the interaction between brain structures involved with stress response and other key functions. Those measurements are combined using a specific formula to produce a figure called the MDDScore – a number from 1 to 100 indicating the percentage likelihood that the individual has major depression. In clinical use the MDDScore would range from 1 to 10.

The initial pilot phase of the study enrolled 36 adults who had been diagnosed with major depression at the MGH, Vanderbilt University or Cambridge Health Alliance in Cambridge, Mass., along with 43 control participants from St. Elizabeth's Hospital in Brighton, Mass. MDDScores for 33 of the 36 patients indicated the presence of depression, while only 8 of the 43 controls had a positive test result. The average score for patients was 85, while the average for controls was 33. A second replication phase enrolled an additional 34 patients from the MGH and Vanderbilt, 31 of whom had a positive MDDScore result. Combining both groups indicated that the test could accurately diagnose major depression with a sensitivity of about 90 percent and a specificity of 80 percent.

"It can be difficult to convince patients of the need for treatment based on the sort of questionnaire now used to rank their reported symptoms," says Bilello. "We expect that the biological basis of this test may provide patients with insight into their depression as a treatable disease rather than a source of self-doubt and stigma. As we accumulate additional data on the MDDScore and perform further studies, we hope it will be useful for predicting treatment response and helping to select the best therapies."

Papakostas adds, "Determining the true utility of this test will require following this small research study with larger trials in clinical settings. But these results are already providing us with intriguing new hints on how powerfully factors such as inflammation – which we are learning has a major role in many serious medical issues – contribute to depression." Papakostas is an associate professor of Psychiatry at Harvard Medical School.

Provided by Massachusetts General Hospital

"Blood test accurately distinguishes depressed patients from healthy controls." February 1st, 2012. http://medicalxpress.com/news/2012-02-blood-accurately-distinguishes-depressed-patients.html

 

Posted by
Robert Karl Stonjek

Severe, rapid memory loss linked to future, fatal strokes

Severe, rapid memory loss may be linked to -- and could predict -- a future deadly stroke, according to research presented at the American Stroke Association's International Stroke Conference 2012.

Researchers found that people who died after stroke had more severe memory loss in the years before stroke compared to people who survived stroke or people who didn't have a stroke.

"We're most surprised that people who died after strokes had such sharp memory declines years before stroke onset" said Qianyi Wang, the study's lead author and a graduate student at the Harvard University School of Public Health in Boston, Mass.

In the study, researchers examined 11,814 people age 50 years and older every two years for signs of declining memory. Study participants were stroke-free at enrollment and were followed up to 10 years. Participants continued in the study if they survived a stroke. They reported 1,820 strokes, including 364 individuals who died after stroke but before the next memory assessment. Average memory loss each year was compared for participants who remained stroke free; participants who survived a stroke, considering their memory loss might be different before and after stroke; and participants who had a stroke but did not survive.

The researchers used a standard word-recall list to measure memory loss. For participants whose memory loss became too severe to use the word lists, researchers interviewed spouses or other caregivers using a standardized assessment. Memory score is expressed in standard deviation units.

The average memory score each year dropped: 

• 0.078 points in those who didn't have a stroke while in the study;
• 0.137 points before stroke in those who later survived a stroke;
• 0.205 points before stroke in those who later died from stroke.

The people who survived a stroke had worse average memory even before the stroke compared to similar individuals who never had a stroke during follow-up. At the time of stroke, memory function dropped an average 0.321 points. This difference is about the same as the average memory decline associated with growing 4.1 years older among those who remained stroke free. Because of the large stroke-related declines, memory impairment was common among stroke survivors.

Increased memory loss may be linked to a higher risk of fatal stroke for several reasons, researchers said.

"People who die after stroke may have worse underlying disease prior to stroke. This suggests early disease is accumulating and that something is happening to these people before they are diagnosed with clinical stroke." said M. Maria Glymour, S.D., senior study author and an assistant professor at the Harvard School of Public Health. "However, memory impairment is associated with increased mortality regardless of stroke. Memory impairment may therefore make patients more vulnerable to death in the wake of the stroke, for reasons that are unrelated to stroke severity. We're not sure which is true and we can't tell with these analyses, but we hope to examine this in the future."

Studies are needed to determine whether the effects of stroke on memory differ for different groups of people; for example, these effects may vary depending on race, gender, geographic location and socioeconomic status.

"Even health conditions that are much more common at older ages may have roots earlier in life," Glymour said. "Your entire life course influences your health in old age."

Provided by American Heart Association

"Severe, rapid memory loss linked to future, fatal strokes." February 1st, 2012. http://medicalxpress.com/news/2012-02-severe-rapid-memory-loss-linked.html

 

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Robert Karl Stonjek

Obesity reduces the size of your brain

(Medical Xpress) -- New research from Uppsala University shows that a specific brain region linked to appetite regulation is reduced in elderly people who are obese. Poor eating habits over a lifetime may therefore weaken brain function that helps us to control our desire to eat. The findings are published in The International Journal of Obesity.

Researchers Samantha Brooks and Helgi Schiöth, of the Department of Neuroscience at Uppsala University, and researchers in London, showed in an earlier article published in BMC Psychiatry that excessive regulation of appetite in those with anorexia nervosa is linked to greater brain volume in the same region. This research also showed that in anorexic females, the more they restrained their eating, the larger this brain region was. 

  

In a new study, Samantha Brooks, together with colleagues from Uppsala University (Christian Benedict, Helgi Schiöth, Elna-Marie Larsson, Håkan Ahlström and Lars Lind) and researchers from other European universities, have now looked at which brain regions, involved in regulation of appetite, are altered in those with long term obesity. By means of magnetic imaging (MRI) the researchers studied the brains of 292 elderly males and females who were classified as consistently obese or normal weight over a five year period before and after the brain scan. In those suffering from obesity a reduction in the frontal part of the brain was found. The researchers further examined the effects of being obese on a brain function linked to self-regulation of food intake, and found cognitive deficits in those who where obese compared to those who were normal weight.

Samantha Brooks explains: “Those elderly people who were consistently obese over a five year period showed reduced frontal brain volume and deficits in a brain function that helps us to control our food intake. Obesity is on the increase in our modern societies, and while our research cannot determine whether obesity causes or is a consequence of reduced brain volume, in light of our previous research it suggests that if you don’t use your brain to think about what you eat, you may not only lose your waist line, but brain volume as well.”

More information: Brooks S et al. Late life obesity is associated with smaller global and regional gray matter volumes: a voxel-based morphometric study. International Journal of Obesity, in press.

Provided by Uppsala University

"Obesity reduces the size of your brain." February 1st, 2012. http://medicalxpress.com/news/2012-02-obesity-size-brain.html

 

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Robert Karl Stonjek