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Stinky frogs are a treasure trove of antibiotic substances

Some of the nastiest smelling creatures on Earth have skin that produces the greatest known variety of anti-bacterial substances that hold promise for becoming new weapons in the battle against antibiotic-resistant infections, scientists are reporting. Their research on amphibians so smelly (like rotten fish, for instance) that scientists term them “odorous frogs” appears in ACS’ Journal of Proteome Research.

Yun Zhang, Wen-Hui Lee and Xinwang Yang explain that scientists long have recognized frogs’ skin as a rich potential source of new antibiotics. Frogs live in warm, wet places where bacteria thrive and have adapted skin that secretes chemicals, known as peptides, to protect themselves from infections. Zhang’s group wanted to identify the specific antimicrobial peptides (AMPs), and the most potent to give scientists clues for developing new antibiotics.

They identified more than 700 of these substances from nine species of odorous frogs and concluded that the AMPs account for almost one-third of all AMPs found in the world, the greatest known diversity of these germ-killing chemicals. Interestingly, some of the AMPs have a dual action, killing bacteria directly and also activating the immune system to assist in the battle.

The authors acknowledge funding from the National Basic Research Program of China and The National Natural Science Foundation of China.

The American Chemical Society is a non-profit organization chartered by the U.S. Congress. With more than 163,000 members, ACS is the world’s largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.

Contact: Michael Bernstein
m_bernstein@acs.org
202-872-6042
American Chemical Society

Study shows medical marijuana laws reduce traffic deaths

A groundbreaking new study shows that laws legalizing medical marijuana have resulted in a nearly nine percent drop in traffic deaths and a five percent reduction in beer sales.

“Our research suggests that the legalization of medical marijuana reduces traffic fatalities through reducing alcohol consumption by young adults,” said Daniel Rees, professor of economics at the University of Colorado Denver who co-authored the study with D. Mark Anderson, assistant professor of economics at Montana State University.

The researchers collected data from a variety of sources including the National Survey on Drug Use and Health, the Behavioral Risk Factor Surveillance System, and the Fatality Analysis Reporting System.

The study is the first to examine the relationship between the legalization of medical marijuana and traffic deaths.

“We were astounded by how little is known about the effects of legalizing medical marijuana,” Rees said. “We looked into traffic fatalities because there is good data, and the data allow us to test whether alcohol was a factor.”

Anderson noted that traffic deaths are significant from a policy standpoint.

“Traffic fatalities are an important outcome from a policy perspective because they represent the leading cause of death among Americans ages five to 34,” he said.

The economists analyzed traffic fatalities nationwide, including the 13 states that legalized medical marijuana between 1990 and 2009. In those states, they found evidence that alcohol consumption by 20- through 29-year-olds went down, resulting in fewer deaths on the road.

The economists noted that simulator studies conducted by previous researchers suggest that drivers under the influence of alcohol tend to underestimate how badly their skills are impaired. They drive faster and take more risks. In contrast, these studies show that drivers under the influence of marijuana tend to avoid risks. However, Rees and Anderson cautioned that legalization of medical marijuana may result in fewer traffic deaths because it’s typically used in private, while alcohol is often consumed at bars and restaurants.

“I think this is a very timely study given all the medical marijuana laws being passed or under consideration,” Anderson said. “These policies have not been research-based thus far and our research shows some of the social effects of these laws. Our results suggest a direct link between marijuana and alcohol consumption.”

The study also examined marijuana use in three states that legalized medical marijuana in the mid-2000s, Montana, Rhode Island, and Vermont. Marijuana use by adults increased after legalization in Montana and Rhode Island, but not in Vermont. There was no evidence that marijuana use by minors increased.

Opponents of medical marijuana believe that legalization leads to increased use of marijuana by minors.

According to Rees and Anderson, the majority of registered medical marijuana patients in Arizona and Colorado are male. In Arizona, 75 percent of registered patients are male; in Colorado, 68 percent are male. Many are under the age of 40. For instance, 48 percent of registered patients in Montana are under 40.

“Although we make no policy recommendations, it certainly appears as though medical marijuana laws are making our highways safer,” Rees said.

The study is entitled, “Medical Marijuana Laws, Traffic Fatalities, and Alcohol Consumption.” It can be found at: http://www.iza.org/en/webcontent/personnel/photos/index_html?key=4915

The University of Colorado Denver offers more than 120 degrees and programs in 13 schools and colleges and serves more than 28,000 students. CU Denver is located on the Denver Campus and the Anschutz Medical Campus in Aurora, Colo.

Contact: David Kelly
david.kelly@ucdenver.edu
303-315-6374
University of Colorado Denver

A new system for forecasting the GDP of autonomous regions

This work presents the technical possibility to carry out within a day after the release of new economic data for the Spanish quarterly accounting, quarterly forecasts for GDP economic growth (Gross Domestic Product) for all of the autonomous regions. This forecast has proven to be reliable and consistent with GDP growth in the Spanish economy, according to Antoni Espasa, Full Professor of Econometrics in the UC3M Statistics Department, one of the authors of this study, in which Angel Cuevas and Enrique M. Quilis, from the Ministry of Tourism, Industry and Trade, and the Ministry of Economy and Finance, respectively, have also participated. The study, entitled Combining Benchmarking and Chain-Linking for Short-Term Regional Forecasting, was presented last year at the DIW Econometric Workshop in Berlin (Germany), and this year at the International Symposium on Forecasting, in Prague (The Czech Republic) and the IWH-CIREQ Macroeconometric Workshop, in Halle (Germany).

This line of research could have applications in the current economic context. In this work, for example, the methodology described is applied to give a quarterly profile of economic growth in each autonomous region for the last 16 years, and the forecasts for the rest of 2011. “This allows us to see the differences in the economic cycles particularly in the latest recession and the budding recovery which began in 2010,” Antoni Espasa pointed out. “The application,” he added, “gives forecasts for growth for all of the autonomous regions that should relate them with budget tightening plans and public deficit objectives.” In the current economic context which is marked by uncertainty and volatility, a tool such as the one presented in this work contributes to clearly improving analysis of the current economic situation and corresponding decision making, according to Professor Espasi.

Forecasting economic times

The data necessary to carry out this type of predictions are those related with the Los Contabilidad Nacional Trimestral de España (CNTR) (National Accounts Data), and the Contabilidad Anual Regional de España (Regional Accounts Data), as well as the monthly and quarterly data on main macroeconomic indicators from each Autonomous Region. Next, econometric techniques of time series models are applied to obtain the forecast, seasonally adjusted and interpolation with reference index. With that, a new instrument is obtained for short-term monitoring which allows analysts to quantify the degree of synchronization among regional economic cycles.

This research is within the framework of the commitment made by the UC3M Instituto Flores de Lemus to analysis and diagnosis of the economic reality. The researchers of this center, lead by Professor Espasa, have a great deal of experience, dating back more than 17 years, in monitoring, forecasting and diagnosis of the real economy, with its monthly bilingual publication of Boletín de Inflación y Análisis Macroeconómico.

More information:

Combining Benchmarking and Chain-Linking for Short-Term Regional Forecasting

Authors: Ángel Cuevas, Enrique M. Quilis; Antoni Espasa

Contact: Ana Herrera
oic@uc3m.es
Carlos III University of Madrid

How the brain strings words into sentences

While it has long been recognized that certain areas in the brain’s left hemisphere enable us to understand and produce language, scientists are still figuring out exactly how those areas divvy up the highly complex processes necessary to comprehend and produce language.

Advances in brain imaging made within the last 10 years have revealed that highly complex cognitive tasks such as language processing rely not only on particular regions of the cerebral cortex, but also on the white matter fiber pathways that connect them.

“With this new technology, scientists started to realize that in the language network, there are a lot more connecting pathways than we originally thought,” said Stephen Wilson, who recently joined the University of Arizona’s department of speech, language and hearing sciences as an assistant professor. “They are likely to have different functions because the brain is not just a homogeneous conglomerate of cells, but there hasn’t been a lot of evidence as to what kind of information is carried on the different pathways.”

Working in collaboration with his colleagues at the UA, the department of neurology at the University of California, San Francisco and the Scientific Institute and University Hospital San Raffaele in Milan, Italy, Wilson discovered that not only are the connecting pathways important for language processing, but they specialize in different tasks.

Two brain areas called Broca’s region and Wernicke’s region serve as the main computing hubs underlying language processing, with dense bundles of nerve fibers linking the two, much like fiber optic cables connecting computer servers. But while it was known that Broca’s and Wernicke’s region are connected by upper and a lower white matter pathways, most research had focused on the nerve cells clustered inside the two language-processing regions themselves.

Working with patients suffering from language impairments because of a variety of neurodegenerative diseases, Wilsons’ team used brain imaging and language tests to disentangle the roles played by the two pathways. Their findings are published in a recent issue of the scientific journal Neuron.

“If you have damage to the lower pathway, you have damage to the lexicon and semantics,” Wilson said. “You forget the name of things, you forget the meaning of words. But surprisingly, you’re extremely good at constructing sentences.”

“With damage to the upper pathway, the opposite is true; patients name things quite well, they know the words, they can understand them, they can remember them, but when it comes to figuring out the meaning of a complex sentence, they are going to fail.”

The study marks the first time it has been shown that upper and lower tracts play distinct functional roles in language processing, the authors write. Only the upper pathway plays a critical role in syntactic processing.

Wilson collected the data while he was a postdoctoral fellow working with patients with neurodegenerative diseases of varying severity, recruited through the Memory and Aging Center at UCSF. The study included 15 men and 12 women around the age of 66.

Unlike many other studies investigating acquired language disorders, which are called aphasias and usually caused by damage to the brain, Wilson’s team had a unique opportunity to study patients with very specific and variable degrees of brain damage.

“Most aphasias are caused by strokes, and most of the strokes that affect language regions probably would affect both pathways,” Wilson said. “In contrast, the patients with progressive aphasias who we worked with had very rare and very specific neurodegenerative diseases that selectively target different brain regions, allowing us to tease apart the contributions of the two pathways.”

To find out which of the two nerve fiber bundles does what in language processing, the team combined magnetic resonance brain imaging technology to visualize damaged areas and language assessment tasks testing the participants’ ability to comprehend and produce sentences.

“We would give the study participants a brief scenario and ask them to complete it with what comes naturally,” Wilson said. “For example, if I said to you, ‘A man was walking along the railway tracks. He didn’t hear the train coming. What happened to the man?’ Usually, you would say, ‘He was hit by the train,’ or something along those lines.”

“But a patient with damage to the upper pathway might say something like ‘train, man, hit.’ We found that the lower pathway has a completely different function, which is in the meaning of single words.”

To test for comprehension of the meaning of a sentence, the researchers presented the patient with a sentence like, “The girl who is pushing the boy is green,” and then ask which of the two pictures depicted that scenario accurately.

“One picture would show a green girl pushing a boy, and the other would show a girl pushing a green boy,” Wilson said. “The colors will be the same, the agents will be the same, and the action is the same. The only difference is, which actor does the color apply to?”

“Those who have only lower pathway damage do really well on this, which shows that damage to that pathway doesn’t interfere with your ability to use the little function words or the functional endings on words to figure out the relationships between the words in a sentence.”

Wilson said that most previous studies linking neurodegeneration of specific regions with cognitive deficits have focused on damage to gray matter, rather than the white matter that connects regions to one another.

“Our study shows that the deficits in the ability to process sentences are above and beyond anything that could be explained by gray matter loss alone,” Wilson added. “It is the first study to show that damage to one major pathway more than then other major pathway is associated with a specific deficit in one aspect of language.”

The study was primarily funded by grants from the National Institutes of Health and included the following co-authors: Sebastian Galantucci, Maria Carmela Tartaglia, Kindle Rising, Dianne Patterson (both at the UA’s department of speech, language and hearing sciences), Maya Henry, Jennifer Ogar, Jessica DeLeon, Bruce Miller and Maria Luisa Gorno-Tempini.

Contact: Daniel Stolte
stolte@email.arizona.edu
520-626-4402
University of Arizona

Rebuilding the brain’s circuitry

Neuron transplants have repaired brain circuitry and substantially normalized function in mice with a brain disorder, an advance indicating that key areas of the mammalian brain are more reparable than was widely believed.

Collaborators from Harvard University, Massachusetts General Hospital, Beth Israel Deaconess Medical Center (BIDMC) and Harvard Medical School (HMS) transplanted normally functioning embryonic neurons at a carefully selected stage of their development into the hypothalamus of mice unable to respond to leptin, a hormone that regulates metabolism and controls body weight. These mutant mice usually become morbidly obese, but the neuron transplants repaired defective brain circuits, enabling them to respond to leptin and thus experience substantially less weight gain.

Repair at the cellular-level of the hypothalamus — a critical and complex region of the brain that regulates phenomena such as hunger, metabolism, body temperature, and basic behaviors such as sex and aggression — indicates the possibility of new therapeutic approaches to even higher level conditions such as spinal cord injury, autism, epilepsy, ALS (Lou Gehrig’s disease), Parkinson’s disease, and Huntington’s disease.

“There are only two areas of the brain that are known to normally undergo ongoing large-scale neuronal replacement during adulthood on a cellular level — so-called ‘neurogenesis,’ or the birth of new neurons — the olfactory bulb and the subregion of the hippocampus called the dentate gyrus, with emerging evidence of lower level ongoing neurogenesis in the hypothalamus,” said Jeffrey Macklis, Harvard University professor of stem cell and regenerative biology and HMS professor of neurology at Massachusetts General Hospital, and one of three corresponding authors on the paper. “The neurons that are added during adulthood in both regions are generally smallish and are thought to act a bit like volume controls over specific signaling. Here we’ve rewired a high-level system of brain circuitry that does not naturally experience neurogenesis, and this restored substantially normal function.”

The two other senior authors on the paper are Jeffrey Flier, dean of Harvard Medical School, and Matthew Anderson, HMS professor of pathology at BIDMC.

The findings are to appear Nov. 25 in Science.

In 2005, Jeffrey Flier, then the George C. Reisman professor of medicine at BIDMC, published a landmark study, also in Science, showing that an experimental drug spurred the addition of new neurons in the hypothalamus and offered a potential treatment for obesity. But while the finding was striking, the researchers were unsure whether the new cells functioned like natural neurons.

Macklis’s laboratory had for several years developed approaches to successfully transplanting developing neurons into circuitry of the cerebral cortex of mice with neurodegeneration or neuronal injury. In a landmark 2000 Nature study, the researchers demonstrated induction of neurogenesis in the cerebral cortex of adult mice, where it does not normally occur. While these and follow-up experiments appeared to rebuild brain circuitry anatomically, the new neurons’ level of function remained uncertain.

To learn more, Flier, an expert in the biology of obesity, teamed up with Macklis, an expert in central nervous system development and repair, and Anderson, an expert in neuronal circuitries and mouse neurological disease models.

The groups used a mouse model in which the brain lacks the ability to respond to leptin. Flier and his lab have long studied this hormone, which is mediated by the hypothalamus. Deaf to leptin’s signaling, these mice become dangerously overweight.

Prior research had suggested that four main classes of neurons enabled the brain to process leptin signaling. Postdocs Artur Czupryn and Maggie Chen, from Macklis’s and Flier’s labs, respectively, transplanted and studied the cellular development and integration of progenitor cells and very immature neurons from normal embryos into the hypothalamus of the mutant mice using multiple types of cellular and molecular analysis. To place the transplanted cells in exactly the correct and microscopic region of the recipient hypothalamus, they used a technique called high-resolution ultrasound microscopy, creating what Macklis called a “chimeric hypothalamus” — like the animals with mixed features from Greek mythology.

Postdoc Yu-Dong Zhou, from Anderson’s lab, performed in-depth electrophysiological analysis of the transplanted neurons and their function in the recipient circuitry, taking advantage of the neurons’ glowing green from a fluorescent jellyfish protein carried as a marker.

These nascent neurons survived the transplantation process and developed structurally, molecularly, and electrophysiologically into the four cardinal types of neurons central to leptin signaling. The new neurons integrated functionally into the circuitry, responding to leptin, insulin, and glucose. Treated mice matured and weighed approximately 30 percent less than their untreated siblings or siblings treated in multiple alternate ways.

The researchers then investigated the precise extent to which these new neurons had become wired into the brain’s circuitry using molecular assays, electron microscopy for visualizing the finest details of circuits, and patch-clamp electrophysiology, a technique in which researchers use small electrodes to investigate the characteristics of individual neurons and pairs of neurons in fine detail. Because the new cells were labeled with fluorescent tags, postdocs Czupryn, Zhou, and Chen could easily locate them.

The Zhou and Anderson team found that the newly developed neurons communicated to recipient neurons through normal synaptic contacts, and that the brain, in turn, signaled back. Responding to leptin, insulin and glucose, these neurons had effectively joined the brain’s network and rewired the damaged circuitry.

“It’s interesting to note that these embryonic neurons were wired in with less precision than one might think,” Flier said. “But that didn’t seem to matter. In a sense, these neurons are like antennas that were immediately able to pick up the leptin signal. From an energy-balance perspective, I’m struck that a relatively small number of genetically normal neurons can so efficiently repair the circuitry.”

“The finding that these embryonic cells are so efficient at integrating with the native neuronal circuitry makes us quite excited about the possibility of applying similar techniques to other neurological and psychiatric diseases of particular interest to our laboratory,” said Anderson.

The researchers call their findings a proof of concept for the broader idea that new neurons can integrate specifically to modify complex circuits that are defective in a mammalian brain.

The researchers are interested in further investigating controlled neurogenesis — directing growth of new neurons in the brain from within — the subject of much of Macklis’s research as well as Flier’s 2005 paper, and a potential route to new therapies.

“The next step for us is to ask parallel questions of other parts of the brain and spinal cord, those involved in ALS and with spinal cord injuries,” Macklis said. “In these cases, can we rebuild circuitry in the mammalian brain? I suspect that we can.”

This study was funded by the National Institutes of Health, the Jane and Lee Seidman Fund for Central Nervous System Research, the Emily and Robert Pearlstein Fund for Nervous System Repair, the Picower Foundation, the National Institute of Neurological Disorders and Stroke, Autism Speaks, and the Nancy Lurie Marks Family Foundation.

- David Cameron

Citation:

Science, Vol. 334 (6059), November 25, 2011

“Transplanted Hypothalamic Neurons Restore Leptin Signaling and Ameliorate Obesity in db/db Mice” by Czupryn et al.

Harvard Medical School (http://hms.harvard.edu) has more than 7,500 full-time faculty working in 11 academic departments located at the School’s Boston campus or in one of 47 hospital-based clinical departments at 17 Harvard-affiliated teaching hospitals and research institutes. Those affiliates include Beth Israel Deaconess Medical Center, Brigham and Women¹s Hospital, Cambridge Health Alliance, Children¹s Hospital Boston, Dana-Farber Cancer Institute, Forsyth Institute, Harvard Pilgrim Health Care, Hebrew SeniorLife, Joslin Diabetes Center, Judge Baker Children¹s Center, Massachusetts Eye and Ear Infirmary, Massachusetts General Hospital, McLean Hospital, Mount Auburn Hospital, Schepens Eye Research Institute, Spaulding Rehabilitation Hospital, and VA Boston Healthcare System.

Celebrating the 200th anniversary of its founding in 1811, Massachusetts General Hospital (http://www.massgeneral.org) is the original and largest teaching hospital of Harvard Medical School. MGH conducts the largest hospital-based research program in the United States, with an annual research budget of nearly $700 million and major research centers in AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, human genetics, medical imaging, neurodegenerative disorders, regenerative medicine, reproductive biology, systems biology, transplantation biology and photomedicine.

Beth Israel Deaconess Medical Center is a patient care, teaching and research affiliate of Harvard Medical School and consistently ranks in the top four in National Institutes of Health funding among independent hospitals nationwide. BIDMC is a clinical partner of the Joslin Diabetes Center and a research partner of the Harvard/Dana-Farber Cancer Center. BIDMC is the official hospital of the Boston Red Sox. For more information, visit http://www.bidmc.org.

Contact: David Cameron
david_cameron@hms.harvard.edu
617-960-7221
Harvard Medical School

UN overhaul required to govern planet’s life support system: Experts

Reducing the risk of potential global environmental disaster requires a “constitutional moment” comparable in scale and importance to the reform of international governance that followed World War II, say experts preparing the largest scientific conference leading up to next June’s Rio+20 Earth Summit.

Stark increases in natural disasters, food and water security problems and biodiversity loss are just part of the evidence that humanity may be crossing planetary boundaries and approaching dangerous tipping points. An effective environmental governance system needs to be instituted soon, according to independent experts commissioned by organizers of the huge “Planet Under Pressure” conference in London March 26-29, 2012.

As policy-makers gather in Durban, South Africa, for the 17th Conference of the Parties to the UN Framework Convention on Climate Change, the Planet Under Pressure consortium today released the first five of nine policy briefs on key issues. The briefs deal with biodiversity and ecosystem services, food and water security, interconnected risks and solutions, and a topic common to all: reforming environmental governance from the local to the global level.

Prof. Frank Biermann of VU University Amsterdam in The Netherlands, director of the Earth System Governance Project of the International Human Dimensions Programme (IHDP) wrote the policy brief on institutional reform with 29 fellow social scientists and governance experts around the world.

Says Dr. Biermann: “Societies must change course to steer away from critical tipping points that lead to rapid and irreversible change. This requires a fundamental transformation of existing practices. The international governance system must change.”

“In the 1940s, large parts of the world lay in ruins amid fears of further political conflict. International systems were inadequate to deal with the global challenges then. Decision-makers created in very short time new organizations and global standards, including the U.N., the General Agreement on Tariffs and Trade (later the World Trade Organization), and others.”

“The current destruction of the Earth’s natural systems warrants today a similar ‘constitutional moment’ to revise and transform the architecture of global governance.”

Says IHDP executive director Anantha Duraiappah: “The governance systems created post-war have helped resolve conflict, promote globalization and spur unprecedented economic growth. Many societies have progressed in the past decades with an increase in well-being. The magic question is can this continue? As the world continues to become ever more interdependent we need new forms of governance.”

Improving international co-ordination is essential to deal not only with global-scale environmental and consequent security problems but to regulate proposed technological fixes, including nanotechnology, biotechnology and climate engineering.

Global-scale geo-engineering proposals to address climate change are too far-reaching and potentially dangerous to be left to the discretion of national governments or corporations, Dr. Biermann says. Multilateral frameworks are instead urgently needed.

“Tinkering with the existing international governance system is unlikely to improve matters sufficiently,” he says. “Fundamental reform is required for effective Earth-system governance.”

Among several recommendations:

Strengthen the system of international organizations for sustainable development by, for example:

• Upgrading the UN Commission on Sustainable Development to a Council of the UN General Assembly, to handle emerging issues such as water, climate, energy and food security, natural disasters and the linkages among these issues;
• Elevating the Nairobi-based UN Environment Programme to the status of the World Health Organization and International Labour Organization – a step that would give it greater authority, more secure funding and facilitate the creation and enforcement of international regulations and standards;
• Create special majority voting in decision-making systems when earth-system concerns are at stake.

Also recommended:

• Strengthening national accountability and legitimacy with, for example, mandatory disclosure of accessible, comprehensible and comparable data about government and corporate sustainability performance; and
• Allowing discrimination in world trade law between products on the basis of production processes to encourage investments in cleaner products and services. Such discrimination should be based on multilateral agreement to prevent protectionism.

Tools available

“We have tools to address our challenges effectively, but we’re quickly running out of time to put them in place,” says Planet Under Pressure conference co-chair Dr Mark Stafford Smith, science director of the Commonwealth Scientific and Industrial Research Organization’s Climate Adaptation Flagship, in Canberra, Australia.

The international Planet Under Pressure conference will be the largest gathering of global change and sustainability scientists prior to the Rio+20 Earth Summit next June in Rio de Janeiro. The 3,000 global experts expected at the London conference will provide a “State of the Planet” assessment, discuss concepts for planetary stewardship and societal and economic transformation, and prescribe a recommended route to global sustainability.

Sponsored by the International Council for Science (ICSU), the conference is being organized by a consortium of four leading global research programmes: International Geosphere-Biosphere Programme, DIVERSITAS-the international programme on biodiversity science, International Human Dimensions Programme on global environmental change, the World Climate Research Programme — collectively known as the Earth System Science Partnership.

Despite more than 900 environmental treaties coming into force in the past 40 years, human-induced environmental degradation continues, reaching levels that prompted ICSU’s blunt warning in 2010 that “humanity has reached a point in history at which a prerequisite for development – the continued functioning of the Earth system as we know it – is at risk.”

Authors of the policy briefs note recently published contentions that humanity has already pushed Earth past limits on climate change, biodiversity loss and nitrogen use — three of nine proposed “planetary boundaries” that must be respected for societies to grow and prosper.

Biodiversity

The brief on biodiversity and ecosystem services notes that despite recent efforts to reduce the rate of loss of biodiversity and ecosystem services, the number of plant and animal species threatened with extinction continues to rise, forests and mangrove swamps are in sharp decline, and vast areas are increasingly dominated by a few successful species.

The brief offers new information detailing the fast-growing number of pollution-related oxygen depletion zones killing fish in coastal marine ecosystems — now more than 500 worldwide.

Consequences include the diminished ability of ecosystems to act as a buffer against extreme events such as floods, fires, disease outbreaks and storm surges. “If the global community continues on its current path, the declines in biodiversity and ecosystem services will impede future efforts towards sustainable development pathways,” the authors warn.

They call for a stronger inclusion of the multiple values of biodiversity and ecosystems into policy and management decisions, e.g. by measuring progress beyond traditional indicators such as the GDP. The concept of ‘inclusive wealth’ includes all forms of capital – natural (land, water, soil, biodiversity and ecosystem services), social (institutions, social networks) and human (education, health, skills) — as well as financial and manufactured.

“While current trends in biodiversity and ecosystem services are sharply and dangerously negative, the right actions — developed and implemented promptly — can restore a biologically rich and ecologically viable planet.” stresses Dr. Anne Larigauderie, executive director of DIVERSITAS and co-author of the brief.

Food security

Led by Oxford University Prof. John Ingram, authors of the food security brief say that despite a marked increase in global food production over the past half century, nearly one billion people still have too little to eat, and a further billion lack adequate nutrition. It showcases a new indicator of food security — children under the age of five suffer stunted growth due to inadequate food — and offers a map showing that in much of the world, the problem affects 40 per cent or more of children.

While the brief calls for the urgent development of policies and technologies for increasing food production in a more sustainable manner, it highlights the need for a food system that recognizes that improving access to food is the key issue to reduce food insecurity, rather than concentrating solely on increasing production.

“The challenge of feeding the world efficiently and equitably is considerable, but not insurmountable,” the authors say. “Institutions operating effectively at multiple levels will be at the centre of sustainable food systems; these will need to be flexible, promote appropriate use of innovative technologies and policies, and recognize the increasingly important role of non-state actors in enhancing food systems. Above all, there is need for a strong focus on resilience, equity and sustainability.”

Water security

As global population has tripled in the past century, water use has increased six-fold, and the quality of water resources has been degraded through human activities such as excessive use of agriculture-related chemicals and the release of untreated sewage and industrial wastewater.

Combined with growing economies and poor water management, unprecedented pressure is being placed on freshwater resources.

The policy document recommends that water be given high priority in international decision-making, and that compromises between use and preservation be made on the basis of science rather than political or economic lobbying. It also calls for laws and financial mechanisms to ensure sustainable water supplies.

“We simply cannot continue to use water as wastefully as we have in the past,” says lead author Janos Bogardi, Executive Officer of the Joint ESSP Global Water Systems Project. “Water must be given the prominence it deserves on the global agenda; decisions should be considered through a ‘water lens’.”

Interconnected risks and solutions

The financial crisis highlights our vulnerability as a direct result of our growing interconnectivity. The brief on interconnected risks and solutions underlines underlines the requirement for an integrated approach to a suite of urgent global challenges: poverty alleviation; the financial crisis; economic development; political stability; pollution; food, water and energy security; health; wellbeing; climate change; ocean acidification; and loss of biodiversity to name just some.

Systemic risk management should be a priority for international organizations.

The experts call for an end to the fragmented approach to interconnected global challenges and suggest establishing an international high-level consultative body on global sustainability. Beneath this, they suggest an Intergovernmental Panel on Sustainable Development to ensure scientific coherence and build on existing assessments for example the Intergovernmental Panel on Climate Change and Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services, and to ensure scientific coherence. This would produce a regular ‘State of the Planet’ assessment that includes socio-economic indicators.

They also call on societies to “build resilience and prepare for unavoidable changes.”

Professor Sybil Seitzinger, Executive Director of the International Geosphere-Biosphere Programme say, “The great acceleration in human activity, seen largely since the 1950s, has committed the Earth system to substantial change, not only this century but also for hundreds and even thousands of years to come.”

Future policy briefs will offer insights and recommendations on the green economy, energy security, health, and human well-being.

Planet Under Pressure (www.planetunderpressure2012.net)

The Planet Under Pressure conference’s chief scientific advisor, Elinor Ostrom, has commissioned a series of policy briefs relevant to Rio+20. These policy briefs have been independently produced by the academic community and will be supported by white papers to be published for the Planet Under Pressure conference. The conference provides a platform for independent, impartial research. The views and the recommendations expressed in the policy briefs should not be taken to reflect the views of all programme sponsors.

Conference structure:

Monday March 26: State of the Planet: latest knowledge about the pressures on the planet

Tuesday March 27: Options and opportunities: exchanging knowledge about ways of reducing the pressures on the planet, promoting transformative changes for a sustainable future and adapting to changes in the global system

Wednesday March 29: Challenges to progress: clarifying what is preventing or slowing humanity from implementing potential solutions

Thursday March 30: Ways ahead: a vision for 2050 and beyond, and exploring new partnerships and pathways towards global sustainability

Themes:
Meeting global needs: food, energy, water and other ecosystem services
Transforming our way of living: development pathways under global environmental change
Governing across scales: innovative stewardship of the Earth system

For more details: www.planetunderpressure2012.net/themes.asp
Conference sessions: www.planetunderpressure2012.net/sessions.asp
Mailing list: http://www.planetunderpressure2012.net/mailinglist.asp
Registration for journalists: 1 December 2011 www.planetunderpressure2012.net

Sponsor

International Council for Science

Founded in 1931, Paris-based ICSU is a non-governmental organization with a global membership of national scientific bodies (121 Members, representing 141 countries) and International Scientific Unions (30 Members). The Council is frequently called upon to speak on behalf of the global scientific community and to act as an advisor in matters ranging from the environment to conduct in science. ICSU’s activities focus on three areas: planning and coordinating research; science for policy; and strengthening the Universality of Science.

Organizers

The Earth System Science Partnership

Based in Paris, France, the ESSP has been created for the integrated study of change in the Earth System and the implications for global and regional sustainability. There are four institutional partners:

International Geosphere-Biosphere Programme

Based in Stockholm, Sweden, IGBP was launched in 1987 to coordinate international research on global-scale and regional-scale interactions between Earth’s biological, chemical and physical processes and their interactions with human systems. IGBP views the Earth system as the Earth’s natural physical, chemical and biological cycles and processes AND the social and economic dimensions.

DIVERSITAS

Paris-based DIVERSITAS is an international programme of biodiversity science with a dual mission: To promote an integrative biodiversity science, linking biological, ecological and social disciplines in an effort to produce socially relevant new knowledge; and to provide the scientific basis for the conservation and sustainable use of biodiversity.

International Human Dimensions Programme on Global Environmental Change

Based in Bonn, Germany, IHDP fosters original research into human behaviours and actions relevant to global environmental changes. IHDP builds international, multi-disciplinary teams of scientists to conduct integrated, long-term collaborative research and adds value by strengthening the voice and impact of a huge network of individual scientists and research initiatives. The Earth System Governance Project is one of IHDP’s core projects and has compiled the Policy Brief on the Institutional Framework for Sustainable Development.

World Climate Research Programme

Based in Geneva, Switzerland, WCRP’s two overarching objectives are to determine the predictability of climate and to determine the effect of human activities on climate. WCRP facilitates analysis and prediction of Earth system variability and change for use in an increasing range of practical applications of direct relevance, benefit and value to society.

Contact: Terry Collins
tc@tca.tc
416-538-8712
Earth System Science Partnership

Dreaming takes the sting out of painful memories

They say time heals all wounds, and new research from the University of California, Berkeley, indicates that time spent in dream sleep can help.

UC Berkeley researchers have found that during the dream phase of sleep, also known as REM sleep, our stress chemistry shuts down and the brain processes emotional experiences and takes the painful edge off difficult memories.

The findings offer a compelling explanation for why people with post-traumatic stress disorder (PTSD), such as war veterans, have a hard time recovering from painful experiences and suffer reoccurring nightmares.They also offer clues into why we dream.

“The dream stage of sleep, based on its unique neurochemical composition, provides us with a form of overnight therapy, a soothing balm that removes the sharp edges from the prior day’s emotional experiences,” said Matthew Walker, associate professor of psychology and neuroscience at UC Berkeley and senior author of the study to be published this Wednesday, Nov. 23, in the journal Current Biology.

For people with PTSD, Walker said, this overnight therapy may not be working effectively, so when a “flashback is triggered by, say, a car backfiring, they relive the whole visceral experience once again because the emotion has not been properly stripped away from the memory during sleep.”

The results offer some of the first insights into the emotional function of Rapid Eye Movement (REM) sleep, which typically takes up 20 percent of a healthy human’s sleeping hours. Previous brain studies indicate that sleep patterns are disrupted in people with mood disorders such as PTSD and depression.

While humans spend one-third of their lives sleeping, there is no scientific consensus on the function of sleep. However, Walker and his research team have unlocked many of these mysteries linking sleep to learning, memory and mood regulation. The latest study shows the importance of the REM dream state.

“During REM sleep, memories are being reactivated, put in perspective and connected and integrated, but in a state where stress neurochemicals are beneficially suppressed,” said Els van der Helm, a doctoral student in psychology at UC Berkeley and lead author of the study.

Thirty – five healthy young adults participated in the study. They were divided into two groups, each of whose members viewed 150 emotional images, twice and 12 hours apart, while an MRI scanner measured their brain activity.

Half of the participants viewed the images in the morning and again in the evening, staying awake between the two viewings. The remaining half viewed the images in the evening and again the next morning after a full night of sleep.

Those who slept in between image viewings reported a significant decrease in their emotional reaction to the images. In addition, MRI scans showed a dramatic reduction in reactivity in the amygdala, a part of the brain that processes emotions, allowing the brain’s “rational” prefrontal cortex to regain control of the participants’ emotional reactions.

In addition, the researchers recorded the electrical brain activity of the participants while they slept, using electroencephalograms. They found that during REM dream sleep, certain electrical activity patterns decreased, showing that reduced levels of stress neurochemicals in the brain soothed emotional reactions to the previous day’s experiences.

“We know that during REM sleep there is a sharp decrease in levels of norepinephrine, a brain chemical associated with stress,” Walker said. “By reprocessing previous emotional experiences in this neuro-chemically safe environment of low norepinephrine during REM sleep, we wake up the next day, and those experiences have been softened in their emotional strength. We feel better about them, we feel we can cope.”

Walker said he was tipped off to the possible beneficial effects of REM sleep on PTSD patients when a physician at a U.S. Department of Veterans Affairs hospital in the Seattle area told him of a blood pressure drug that was inadvertently preventing reoccurring nightmares in PTSD patients.

It turns out that the generic blood pressure drug had a side effect of suppressing norepinephrine in the brain, thereby creating a more stress-free brain during REM, reducing nightmares and promoting a better quality of sleep. This suggested a link between PTSD and REM sleep, Walker said.

“This study can help explain the mysteries of why these medications help some PTSD patients and their symptoms as well as their sleep,” Walker said. “It may also unlock new treatment avenues regarding sleep and mental illness.”

Other co-authors of the study are UC Berkeley sleep researchers Justin Yao, Shubir Dutt, Vikram Rao and Jared Saletin.

Contact: Yasmin Anwar
yanwar@berkeley.edu
510-643-7944
University of California – Berkeley

ew projection shows global food demand doubling by 2050

Global food demand could double by 2050, according to a new projection reported this week in the journal Proceedings of the National Academy of Sciences (PNAS).

The analysis also shows that the world faces major environmental challenges unless agricultural practices change.

Scientists David Tilman and Jason Hill of the University of Minnesota (UMN) and colleagues found that producing the amount of food needed could significantly increase levels of carbon dioxide and nitrogen in the environment, and may cause the extinction of numerous species.

These problems can be avoided, the researchers say, if the high-yielding technologies of wealthier nations are adapted to work in poorer nations, and if all countries use nitrogen fertilizers more efficiently.

In their paper, the scientists explore various ways of meeting the demand for food, and their environmental effects.

The options, they found, are to increase productivity on existing agricultural land, clear more land, or a combination of both.

They also consider various scenarios in which the amount of nitrogen use, land cleared, and resulting greenhouse gas emissions differ.

“Agriculture’s greenhouse gas emissions could double by 2050 if current trends in global food production continue,” Tilman said. “This would be a major problem, since global agriculture already accounts for a third of all greenhouse gas emissions.”

“Ever increasing global demands for food pit environmental health against human prosperity,” said Saran Twombly, program director in the National Science Foundation (NSF)’s Division of Environmental Biology, which funded the research.

“These assessments show that agricultural intensification, through improved agronomic practices and technology transfer, best ensure the latter with minimal costs to the former,” Twombly said.

“The results challenge wealthy nations to invest technologically in underyielding nations to alter the current global trajectory of agricultural expansion,” she believes. “Identifying the economic and political incentives needed to realize this investment is the critical next step.”

The environmental effects of meeting the demand for food depend on how global agriculture expands.

The research shows that adopting nitrogen-efficient “intensive” farming can meet future global food demand with much lower environmental effects, vs. the “extensive” farming practiced by many poor nations, which clears land to produce more food.

The potential benefits are great, the researchers believe.

In 2005, crop yields for the wealthiest nations were more than 300 percent higher than yields for the poorest nations.

“Strategically intensifying crop production in developing and least-developed nations would reduce the overall environmental harm caused by food production, as well as provide a more equitable food supply across the globe,” said Hill.

If poorer nations continue current practices, they will clear a land area larger than the United States (two and a half billion acres) by 2050. But if richer nations help poorer nations to improve yields, that number could be reduced to half a billion acres.

“Our analyses show that we can save most of the Earth’s remaining ecosystems,” said Tilman, “by helping the poorer nations of the world feed themselves.”

Scientists Christian Balzer of the University of California Santa Barbara and Belinda Befort of UMN are also co-authors of the paper.

Contact: Cheryl Dybas,
cdybas@nsf.gov
703-292-7734
National Science Foundation

The impending revolution of low-power quantum computers

By 2017, quantum physics will help reduce the energy consumption of our computers and cellular phones by up to a factor of 100. For research and industry, the power consumption of transistors is a key issue. The next revolution will likely come from tunnel-FET, a technology that takes advantage of a phenomenon referred to as “quantum tunneling.” At the EPFL, but also in the laboratories of IBM Zurich and the CEA-Leti in France, research is well underway. As part of a special issue of Nature devoted to silicon, Adrian Ionescu, an EPFL researcher, has written an article on the topic.

Transistors that exploit a quantum quirk

Today’s computers have no less than a billion transistors in the CPU alone. These small switches that turn on and off provide the famous binary instructions, the 0s and 1s that let us send emails, watch videos, move the mouse pointer… and much more. The technology used in today’s transistors is called “field effect;” whereby voltage induces an electron channel that activates the transistor. But field effect technology is approaching its limits, particularly in terms of power consumption.

Tunnel-FET technology is based on a fundamentally different principle. In the transistor, two chambers are separated by an energy barrier. In the first, a horde of electrons awaits while the transistor is deactivated. When voltage is applied, they cross the energy barrier and move into the second chamber, activating the transistor in so doing.

In the past, the tunnel effect was known to disrupt the operation of transistors. According to quantum theory, some electrons cross the barrier, even if they apparently don’t have enough energy to do so. By reducing the width of this barrier, it becomes possible to amplify and take advantage of the quantum effect – the energy needed for the electrons to cross the barrier is drastically reduced, as is power consumption in standby mode.

Mass production is imminent

“By replacing the principle of the conventional field effect transistor by the tunnel effect, one can reduce the voltage of transistors from 1 volt to 0.2 volts,” explains Ionescu. In practical terms, this decrease in electrical tension will reduce power consumption by up to a factor of 100. The new generation microchips will combine conventional and tunnel-FET technology. “The current prototypes by IBM and the CEA-Leti have been developed in a pre-industrial setting. We can reasonably expect to see mass production by around 2017.”

An essential technology for a major European project

For Ionescu, who heads the Guardian Angels project (a project vetted for a billion Euro grant from the EU), tunnel-FET technology is without a doubt the next big technological leap in the field of microprocessors. “In the Guardian Angels project, one of our objectives is to find solutions to reduce the power consumption of processors. Tunnel-FET is the next revolution that will help us achieve this goal.” The aim: design ultra-miniaturized, zero-power electronic personal assistants. Tunnel-FET technology is one of the first major stages in the project’s roadmap. IBM and the CEA-Leti are also partners in the project.

Contact :

Adrian Ionescu, Nanoelectronic Devices Laboratory, EPFL, adrian.ionescu@epfl.ch or 41-21-693-39-78 / 41-21-693-39-79

Lionel Pousaz, Media and Communication Service, lionel.pousaz@epfl.ch or 41-79-559-71-61

Reference :

Nature : Tunnel field-effect transistors as energy-efficient electronic switches

Link:

http://www.nature.com/nature/journal/v479/n7373/full/nature10679.html

Psychopaths’ brains show differences in structure and function

Images of prisoners’ brains show important differences between those who are diagnosed as psychopaths and those who aren’t, according to a new study led by University of Wisconsin-Madison researchers.

The results could help explain the callous and impulsive anti-social behavior exhibited by some psychopaths.

The study showed that psychopaths have reduced connections between the ventromedial prefrontal cortex (vmPFC), the part of the brain responsible for sentiments such as empathy and guilt, and the amygdala, which mediates fear and anxiety. Two types of brain images were collected. Diffusion tensor images (DTI) showed reduced structural integrity in the white matter fibers connecting the two areas, while a second type of image that maps brain activity, a functional magnetic resonance image (fMRI), showed less coordinated activity between the vmPFC and the amygdala.

“This is the first study to show both structural and functional differences in the brains of people diagnosed with psychopathy,” says Michael Koenigs, assistant professor of psychiatry in the University of Wisconsin School of Medicine and Public Health. “Those two structures in the brain, which are believed to regulate emotion and social behavior, seem to not be communicating as they should.”

The study, which took place in a medium-security prison in Wisconsin, is a unique collaborative between three laboratories,

UW-Madison psychology Professor Joseph Newman has had a long term interest in studying and diagnosing those with psychopathy and has worked extensively in the Wisconsin corrections system. Dr. Kent Kiehl, of the University of New Mexico and the MIND Research Network, has a mobile MRI scanner that he brought to the prison and used to scan the prisoners’ brains. Koenigs and his graduate student, Julian Motzkin, led the analysis of the brain scans.

The study compared the brains of 20 prisoners with a diagnosis of psychopathy with the brains of 20 other prisoners who committed similar crimes but were not diagnosed with psychopathy.

“The combination of structural and functional abnormalities provides compelling evidence that the dysfunction observed in this crucial social-emotional circuitry is a stable characteristic of our psychopathic offenders,” Newman says. “I am optimistic that our ongoing collaborative work will shed more light on the source of this dysfunction and strategies for treating the problem.”

Newman notes that none of this work would be possible without the extraordinary support provided by the Wisconsin Department of Corrections, which he called “the silent partner in this research.” He says the DOC has demonstrated an unprecedented commitment to supporting research designed to facilitate the differential diagnosis and treatment of prisoners.

The study, published in the most recent Journal of Neuroscience, builds on earlier work by Newman and Koenigs that showed that psychopaths’ decision-making mirrors that of patients with known damage to their ventromedial prefrontal cortex (vmPFC). This bolsters evidence that problems in that part of the brain are connected to the disorder.

“The decision-making study showed indirectly what this study shows directly – that there is a specific brain abnormality associated with criminal psychopathy,” Koenigs adds.

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