Common blood thinner for pregnant women proven ineffective

It’s a daily injection to the belly for pregnant women at risk of developing blood clots and it’s ineffective, according to a clinical trial led by researchers at The Ottawa Hospital and published today by the medical journal The Lancet.As many as one in 10 pregnant women have a tendency to develop blood clots in their veins, a condition called thrombophilia. For two decades these women have often been prescribed the anticoagulant low molecular weight heparin (LMWH) to prevent pregnancy complications caused by placental blood clots. This treatment requires women to give themselves daily injections — a painful and demoralizing process that requires women to poke their abdomen with hundreds of needles over the course of their pregnancy.Now, a randomized clinical trial led by Dr. Marc Rodger, a senior scientist at the Ottawa Hospital Research Institute who heads up the Thrombosis Program of The Ottawa Hospital, provides conclusive evidence that the commonly prescribed LMWH anticoagulant has no positive benefits for the mother or child. In fact, Dr. Rodger’s study shows that LMWH treatments could actually cause pregnant women some minor harm by increasing bleeding, increasing their rates of induced labour and reducing their access to anesthesia during childbirth.”These results mean that many women around the world can save themselves a lot of unnecessary pain during pregnancy,” says Dr. Rodger, who is also a professor in the Faculty of Medicine at the University of Ottawa. “Using low molecular weight heparin unnecessarily medicalizes a woman’s pregnancy and is costly.”Since the 1990s, using LMWH to treat pregnant women with a tendency to develop blood clots became commonplace, despite the fact that a large, multi-site randomized clinical trial had never been conducted to prove its effectiveness. Low molecular weight heparin is also prescribed by many physicians worldwide to women, with and without thrombophilia, to prevent placenta blood clots that may lead to pregnancy loss, as well as preeclampsia (high blood pressure), placental abruption (heavy bleeding) and intra-uterine growth restrictions (low birth weight babies). The anticoagulant LMWH is also prescribed to prevent deep vein thrombosis (leg vein blood clots) and pulmonary embolisms (lung blood clots).”While I wish we could have shown that LMWH prevents complications, we actually proved it doesn’t help,” adds Dr. …

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Climate Change Increases Risk of Crop Slowdown in Next 20 Years

The world faces a small but substantially increased risk over the next two decades of a major slowdown in the growth of global crop yields because of climate change, new research finds.The authors, from Stanford University and the National Center for Atmospheric Research (NCAR), say the odds of a major production slowdown of wheat and corn even with a warming climate are not very high. But the risk is about 20 times more significant than it would be without global warming, and it may require planning by organizations that are affected by international food availability and price.”Climate change has substantially increased the prospect that crop production will fail to keep up with rising demand in the next 20 years,” said NCAR scientist Claudia Tebaldi, a co-author of the study.Stanford professor David Lobell said he wanted to study the potential impact of climate change on agriculture in the next two decades because of questions he has received from stakeholders and decision makers in governments and the private sector.”I’m often asked whether climate change will threaten food supply, as if it’s a simple yes or no answer,” Lobell said. “The truth is that over a 10- or 20-year period, it depends largely on how fast Earth warms, and we can’t predict the pace of warming very precisely. So the best we can do is try to determine the odds.”Lobell and Tebaldi used computer models of global climate, as well as data about weather and crops, to calculate the chances that climatic trends would have a negative effect of 10 percent on yields of corn and wheat in the next 20 years. This would have a major impact on food supply. Yields would continue to increase but the slowdown would effectively cut the projected rate of increase by about half at the same time that demand is projected to grow sharply.They found that the likelihood of natural climate shifts causing such a slowdown over the next 20 years is only 1 in 200. But when the authors accounted for human-induced global warming, they found that the odds jumped to 1 in 10 for corn and 1 in 20 for wheat.The study appears in this month’s issue of Environmental Research Letters. It was funded by the National Science Foundation (NSF), which is NCAR’s sponsor, and by the U.S. Department of Energy (DOE).More crops needed worldwideGlobal yields of crops such as corn and wheat have typically increased by about 1-2 percent per year in recent decades, and the U.N. Food and Agriculture Organization projects that global production of major crops will increase by 13 percent per decade through 2030 — likely the fastest rate of increase during the coming century. …

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Facial transplantation: Almost a decade out, surgeons prepare for burgeoning demand

Plastic and reconstructive surgeons leading the first retrospective study of all known facial transplants worldwide conclude that the procedure is relatively safe, increasingly feasible, and a clear life-changer that can and should be offered to far more carefully selected patients.Reporting in The Lancet online April 27, NYU Langone plastic and reconstructive surgeon and senior author Eduardo Rodriguez, MD, DDS, says results after nearly a decade of experience with what he calls the “Mount Everest” of medical-surgical treatments are “highly encouraging.”The review team noted that the transplants still pose lifelong risks and complications from infection and sometimes toxic immunosuppressive drugs, but also are highly effective at restoring people to fully functioning lives after physically disfiguring and socially debilitating facial injuries.Surgeons base their claims on the experience of 28 people known to have had full or partial face transplants since 2005, when the first such procedure was performed on a woman in France.Of the 22 men and six women whose surgeries were reported, including seven Americans, none have chronically rejected their new organs and tissues, says Dr. Rodriguez, chair of the Department of Plastic Surgery at NYU Langone Medical Center and director of its Institute of Reconstructive Plastic Surgery. All but three recipients are still living. Four have returned to work or school.Dr. Rodriguez, the Helen L. Kimmel Professor of Reconstructive Plastic Surgery at NYU Langone, in 2012 performed what is widely considered the most extensive facial transplant (when he practiced at the University of Maryland Medical Center in Baltimore). The patient was a Virginia man who had lost the lower half of his face in a gunshot accident 10 years earlier. Dr. Rodriguez is currently readying his new team at NYU Langone to perform its first facial transplantation, expected later this year.In The Lancet article, Dr. Rodriguez and his colleagues point out that although all recipients to date have experienced some complications from infection, and mild to moderate signs of rejection, the few deaths among patients were due to infection and cancer not directly related to their transplants. …

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Scientists report success growing cartilage to reconstruct nostrils and implanting tissue-engineered vaginal organs into humans

Two new articles published in The Lancet report the first ever successful operations in humans to reconstruct the alar wings of the nose (nostrils) (Martin et al), and to implant tissue-engineered vaginal organs in women with a rare syndrome that causes the vagina to be underdeveloped or absent (Atala et al), in both cases using the patients’ own tissue.In one paper, led by Professor Ivan Martin from the University of Basel in Switzerland, scientists report having engineered a human cartilage graft from patients’ own nasal septum cartilage cells to successfully rebuild the nostrils (alar lobule) of five individuals whose noses were damaged by skin cancer. One year after reconstruction, all five recipients were satisfied with their ability to breathe, as well as the cosmetic appearance of their nose, and did not report any local or systemic adverse events.The nose is the most common site of non-melanoma skin cancer, because of its cumulative exposure to sunlight, with the highest frequency of cancer occurring on the alar lobule. Currently, when removing skin cancers, surgeons often have to cut away parts of cartilage, (for instance from the nasal septum, ear, or rib) as grafts to functionally reconstruct the tumour excision site. However, this painful and invasive procedure involves major additional surgery, and has been associated with complications at the site from which cartilage has been removed.A team from the University of Basel, Switzerland, investigated an alternative approach using engineered cartilage tissue grown from patients’ own cells. They extracted the cartilage cells (chondrocytes) from the nasal septum of each patient, and multiplied the cells by exposing them to growth factors for two weeks. The expanded cells were seeded onto collagen membranes and cultured for two additional weeks, generating cartilage 40 times larger than the original biopsy. When the engineered grafts were ready they were shaped according to the defect and implanted.According to Professor Martin, “The engineered cartilage had clinical results comparable to the gold standard cartilage graft surgery. This new technique could help the body accept the new tissue more easily, and improve the stability and functionality of the nostril. Our success is based on the long-standing, effective integration in Basel between our experimental group at the Department of Biomedicine and the surgical disciplines. It opens the way to using this engineered cartilage for more challenging reconstructions in facial surgery such as the complete nose, eyelid, or ear. …

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BOSS quasars track the expanding universe: Most precise measurement yet

The Baryon Oscillation Spectroscopic Survey (BOSS), the largest component of the third Sloan Digital Sky Survey (SDSS-III), pioneered the use of quasars to map density variations in intergalactic gas at high redshifts, tracing the structure of the young universe. BOSS charts the history of the universe’s expansion in order to illuminate the nature of dark energy, and new measures of large-scale structure have yielded the most precise measurement of expansion since galaxies first formed.The latest quasar results combine two separate analytical techniques. A new kind of analysis, led by physicist Andreu Font-Ribera of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and his team, was published late last year. Analysis using a tested approach, but with far more data than before, has just been published by Timothe Delubac, of EPFL Switzerland and France’s Centre de Saclay, and his team. The two analyses together establish the expansion rate at 68 kilometers per second per million light years at redshift 2.34, with an unprecedented accuracy of 2.2 percent.”This means if we look back to the universe when it was less than a quarter of its present age, we’d see that a pair of galaxies separated by a million light years would be drifting apart at a velocity of 68 kilometers a second as the universe expands,” says Font-Ribera, a postdoctoral fellow in Berkeley Lab’s Physics Division. “The uncertainty is plus or minus only a kilometer and a half per second.” Font-Ribera presented the findings at the April 2014 meeting of the American Physical Society in Savannah, GA.BOSS employs both galaxies and distant quasars to measure baryon acoustic oscillations (BAO), a signature imprint in the way matter is distributed, resulting from conditions in the early universe. While also present in the distribution of invisible dark matter, the imprint is evident in the distribution of ordinary matter, including galaxies, quasars, and intergalactic hydrogen.”Three years ago BOSS used 14,000 quasars to demonstrate we could make the biggest 3D maps of the universe,” says Berkeley Lab’s David Schlegel, principal investigator of BOSS. “Two years ago, with 48,000 quasars, we first detected baryon acoustic oscillations in these maps. Now, with more than 150,000 quasars, we’ve made extremely precise measures of BAO.”The BAO imprint corresponds to an excess of about five percent in the clustering of matter at a separation known as the BAO scale. …

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Gastro outbreaks hit elderly hardest

Frail elderly people living in residential care facilities are at increased risk of severe illness or death from outbreaks of viral gastroenteritis.This is the finding from a study led by Craig Davis from Department of Health Queensland, published in the April issue of the Australian and New Zealand Journal of Public Health.”Importantly, prompt notification of outbreaks to public health units led to a much shorter duration of the outbreak,” Mr Davis said.”Notification of outbreaks to public health units should occur within 24 hours of any outbreak so that diagnostic testing and control measures can begin as soon as possible.”A number of viruses may cause outbreaks, but norovirus is by far the most common.”It typically causes vomiting, watery diarrhea, nausea and abdominal cramps with symptoms such as fatigue, myalgia, headache, chills and fever. There is no specific treatment and no vaccine for norovirus. Gastro outbreaks cause a considerable burden in residential care facilities, including disruptions relating to staff absenteeism due to illness, closure of common areas to residents, cancellation of events and increased attention required to infection control.Story Source:The above story is based on materials provided by Wiley. Note: Materials may be edited for content and length.

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Misleading mineral may have resulted in overestimate of water in moon

The amount of water present in the moon may have been overestimated by scientists studying the mineral apatite, says a team of researchers led by Jeremy Boyce of the UCLA Department of Earth, Planetary and Space Sciences.Boyce and his colleagues created a computer model to accurately predict how apatite would have crystallized from cooling bodies of lunar magma early in the moon’s history. Their simulations revealed that the unusually hydrogen-rich apatite crystals observed in many lunar rock samples may not have formed within a water-rich environment, as was originally expected.This discovery has overturned the long-held assumption that the hydrogen in apatite is a good indicator of overall lunar water content.”The mineral apatite is the most widely used method for estimating the amount of water in lunar rocks, but it cannot be trusted,” said Boyce, who is an adjunct assistant professor in the UCLA College of Letters and Science. “Our new results show that there is not as much water in lunar magma as apatite would have us believe.”The research was published online March 20 in the journal Science on and will be published in a future print edition.For decades, scientists believed the moon was almost entirely devoid of water. However, the discovery of hydrogen-rich apatite within lunar rocks in 2010 seemed to hint at a more watery past. Scientists originally assumed that information obtained from a small sample of apatite could predict the original water content of a large body of magma, or even the entire moon, but Boyce’s study indicates that apatite may, in fact, be deceptive.Boyce believes the high water content within lunar apatite results from a quirk in the crystallization process rather than a water-rich lunar environment. When water is present as molten rock cools, apatite can form by incorporating hydrogen atoms into its crystal structure. However, hydrogen will be included in the newly crystallizing mineral only if apatite’s preferred building blocks, fluorine and chlorine, have been mostly exhausted.”Early-forming apatite is so fluorine-rich that it vacuums all the fluorine out of the magma, followed by chlorine,” Boyce said. “Apatite that forms later doesn’t see any fluorine or chlorine and becomes hydrogen-rich because it has no choice.”Therefore, when fluorine and chlorine become depleted, a cooling body of magma will shift from forming hydrogen-poor apatite to forming hydrogen-rich apatite, with the latter not accurately reflecting the original water content in the magma.Understanding the story of lunar apatite has implications beyond determining how much water is locked inside lunar rocks and soil. According to the predominant theory of how the moon originally formed, hydrogen and other volatile elements should not be present at all in lunar rocks.Many scientists theorize that the moon formed when a giant impact tore free a large chunk of Earth more than 4 billion years ago. If this “giant impact” model is correct, the moon would have been completely molten, and lighter elements such as hydrogen should have bubbled to the surface and escaped into space. …

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New Capsicum annuum pepper contains high concentrations of beneficial capsinoids

Researchers have released a new Capsicum annuum pepper germplasm that contains high concentrations of capsinoids. The release was announced in the January 2014 issue of HortScience by researchers Robert L. Jarret from the USDA/Agricultural Research Service in Griffin, Georgia, in collaboration with Jason Bolton and L. Brian Perkins from the Department of Food Science and Human Nutrition at the University of Maine.According to the report, the germplasm called “509-45-1” is a small-fruited Capsicum annuum L. pepper. Fruit of 509-45-1 contain high concentrations of capsiate in both immature and mature fruit. “The release of 509-45-1 will provide researchers and plant breeders with a new source of capsinoids, thus facilitating the production of and further research on these non-pungent biologically active compounds,” Jarret said.Pungent capsaicinoids–the compounds found in the capsicum family of plants that give them their signature heat–have many benefits. Unfortunately, their use as ingredients in foods and pharmaceuticals has been limited by the very characteristic that makes them popular as a spice–their pungency. Non-pungent capsinoids, analogs of capsaicinoids, were first isolated from a sweet pepper cultivar. Capsinoids offer similar types of biological activity as capsaicinoids without the pungency, and are known to provide antioxidant activity, enhance adrenal function, promote metabolism, and suppress body fat accumulation.The scientists began the breeding process in 2005 by screening 120 Capsicum annuum cultivars for the occurrence of capsinoids. …

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Eating seven or more portions of fruit and vegetables a day reduces your risk of death by 42 percent

Eating seven or more portions of fruit and vegetables a day reduces your risk of death at any point in time by 42% compared to eating less than one portion, reports a new UCL study.Researchers used the Health Survey for England to study the eating habits of 65,226 people representative of the English population between 2001 and 2013, and found that the more fruit and vegetables they ate, the less likely they were to die at any age. Eating seven or more portions reduces the specific risks of death by cancer and heart disease by 25% and 31% respectively. The research also showed that vegetables have significantly higher health benefits than fruit.This is the first study to link fruit and vegetable consumption with all-cause, cancer and heart disease deaths in a nationally-representative population, the first to quantify health benefits per-portion, and the first to identify the types of fruit and vegetable with the most benefit.Compared to eating less than one portion of fruit and vegetables, the risk of death by any cause is reduced by 14% by eating one to three portions, 29% for three to five portions, 36% for five to seven portions and 42% for seven or more. These figures are adjusted for sex, age, cigarette smoking, social class, Body Mass Index, education, physical activity and alcohol intake, and exclude deaths within a year of the food survey.The study, published in the Journal of Epidemiology & Community Health, found that fresh vegetables had the strongest protective effect, with each daily portion reducing overall risk of death by 16%. Salad contributed to a 13% risk reduction per portion, and each portion of fresh fruit was associated with a smaller but still significant 4% reduction.”We all know that eating fruit and vegetables is healthy, but the size of the effect is staggering,” says Dr Oyinlola Oyebode of UCL’s Department of Epidemiology & Public Health, lead author of the study. “The clear message here is that the more fruit and vegetables you eat, the less likely you are to die at any age. Vegetables have a larger effect than fruit, but fruit still makes a real difference. If you’re happy to snack on carrots or other vegetables, then that is a great choice but if you fancy something sweeter, a banana or any fruit will also do you good.”The findings lend support to the Australian government’s ‘Go for 2 + 5’ guidelines, which recommend eating two portions of fruit and five of vegetables. The UK Department of Health recommends ‘5 a day’, while ‘Fruit and Veggies — More Matters’ is the key message in the USA.”Our study shows that people following Australia’s ‘Go for 2 + 5’ advice will reap huge health benefits,” says Dr Oyebode. “However, people shouldn’t feel daunted by a big target like seven. …

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Health costs of air pollution from agriculture clarified

Ammonia pollution from agricultural sources poses larger health costs than previously estimated, according to NASA-funded research.Harvard University researchers Fabien Paulot and Daniel Jacob used computer models including a NASA model of chemical reactions in the atmosphere to better represent how ammonia interacts in the atmosphere to form harmful particulate matter. The improved simulation helped the scientists narrow in on the estimated health costs from air pollution associated with food produced for export — a growing sector of agriculture and a source of trade surplus.”The ‘cost’ is an economic concept to measure how much people are willing to pay to avoid a risk,” Paulot said. “This is used to quantify the cost for society but also to evaluate the benefits of mitigation.”The new research by Paulot and Jacob calculate the health cost associated with the ammonia emissions from agriculture exports to be $36 billion a year — equal to about half of the revenue generated by those same exports — or $100 per kilogram of ammonia. The study was published December 2013 in Environmental Science & Technology.The new estimate is about double the current estimate by the U.S. Environmental Protection Agency, which suggests a cost of $47 per kilogram of ammonia. The scientists say the new estimate is on the high end of the spectrum, which reflects the need for more research into characterizing the relationship between agricultural ammonia emissions and the formation of the harmful fine particulate matter — a relationship that’s not as straightforward as previous estimates assumed.”The effect of ammonia on fine particulate is complex, and we believe that the models previously used in the United States to price ammonia emissions have not captured this well,” Paulot said.Manure from livestock and fertilizer for crops release ammonia to the atmosphere. In the air, ammonia mixes with other emissions to form microscopic airborne particles, or particulates. The particulates that pose the greatest health risk are those that measure no more than 2.5 micrometers across, or about 1/30 the width of a human hair, which when inhaled can become lodged deep within the lungs. Long-term exposure has been linked to heart and lung diseases and even death. As such, the particles are on the list of six common air pollutants regulated by EPA’s National Ambient Air Quality Standards.An increase in ammonia, however, does not translate to an equal increase in particulates. …

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New approach to leukemia testing may better define prognosis, treatment

Nearly half of patients with the most common form of adult leukemia are said to have normal chromosomes but appear instead to have a distinct pattern of genetic abnormalities that could better define their prognosis and treatment, researchers report.Using microarray technology that probes millions of genes within chromosomes, researchers found the unique pattern in the leukemia cells of 22 patients diagnosed with cytogenetically normal acute myelogenous leukemia, said Dr. Ravindra Kolhe, molecular pathologist at the Medical College of Georgia at Georgia Regents University.”This is a total game changer,” Kolhe said. “We have to use more sensitive tests to give patients the proper answer.”Kolhe, Director of the Georgia Esoteric, Molecular Labs, LLC, Department of Pathology, presented the findings March 29 during the American College of Medical Genetics and Genomics Annual Clinical Genetics Meeting in Nashville.Acute myelogenous leukemia, the most common type of acute leukemia in adults, has about 20 subtypes, according to the National Cancer Institute. Patients with cytogenetically normal acute myelogenous leukemia experience widely varying outcomes following chemotherapy and bone marrow transplants. Ideally, identifying the causative genes will lead to a more targeted therapy and definitive prognosis, Kolhe said.”The technology we currently use can’t identify specifically what’s wrong,” Kolhe said. Patients have high percentages of cancer-producing cells called blasts in their blood and bone marrow but they do not show the distinctive chromosomal alterations that typically help characterize the leukemia and strategize therapy.Genetic abnormalities, inherited and/or caused by environmental exposures — including previous chemotherapy and radiation treatment — are thought to cause leukemia. The result is that a disproportionate number of stem cells get stuck in the blast, or cancerous, stage, rather than maturing to white blood cells that actually fight cancer and other invaders.Patients often feel tired and feverish and blood tests reveal high blast levels. Pathologists then take about 20 leukemia cells, chemically block their constant division, open the nucleus, and spread the chromosomes on a slide. They examine the chromosomes with a microscope and in-situ hybridization technology, which helps detect small deletions or rearrangements.”(Cytogenetically normal patients) show a normal chromosomal picture but they are clearly sick,” Kolhe said. Frustrated at being unable to give these patients better information, he partnered with California-based Affymetrix to look directly at the genes within chromosomes using CytoScanHD microarray technology.When he put cell contents instead on a computer chip with 2.7 million genetic probes, small, previously undetectable changes in the DNA became apparent in patients who had been classified as cytogenetically normal. …

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Pesticides make the life of earthworms miserable

Pesticides are sprayed on crops to help them grow, but the effect on earthworms living in the soil under the plants is devastating, new research reveals: The worms only grow to half their normal weight and they do not reproduce as well as worms in fields that are not sprayed.Pesticides have a direct impact on the physiology and behavior of earthworms, a Danish/French research team reports after having studied earthworms that were exposed to pesticides over generations.”We see that the worms have developed methods to detoxify themselves, so that they can live in soil sprayed with fungicide. They spend a lot of energy on detoxifying, and that comes with a cost: The worms do not reach the same size as other worms, and we see that there are fewer of them in sprayed soil. An explanation could be that they are less successful at reproducing, because they spend their energy on ridding themselves of the pesticide,” the researchers, Ph. D. student Nicolas Givaudan and associate professor, Claudia Wiegand, say.Claudia Wiegand is from the Department of Biology at University of Southern Denmark, and she led the research together with Francoise Binet from University Rennes 1 in France. Nicolas Givaudan is doing his Ph. D. as a joint degree between University of Southern Denmark and University of Rennes 1 in France. They researchers reached their findings by metabolomic profiling and energetic parameters.The researchers set up an experiment to study the behavior of the earthworm species Aporectodea caliginosa. They moved two portions of farmed soil with worms into the lab. …

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Simple changes to homework improved student learning

A new study offers evidence that simple and inexpensive changes to existing courses can help students learn more effectively.The study from Rice University and Duke University found that making a few changes to homework assignments in an upper-level undergraduate engineering course at Rice led to improved scores on exams. The study appears this week in the journal Educational Psychology Review.The findings by a team from Rice’s Center for Digital Learning and Scholarship and Duke’s Department of Psychology and Neuroscience demonstrate how technology and cognitive science can be combined to develop inexpensive but effective educational changes that required no changes to course curriculum.”Based on laboratory studies, we know a lot about how people learn,” said lead author Andrew Butler, a postdoctoral researcher at Duke. “To test how well some of those cognitive science principles worked in a classroom, we made subtle changes to standard homework practice.””The results exceeded everyone’s expectations,” said Rice co-author Richard Baraniuk, the instructor of the upper-level “signals and systems” engineering course where the experiment took place. “These simple changes produced a larger effect than the average improvement for classroom interventions that require a complete overhaul of curricula and/or teaching methods.”In the study, students switched back and forth from week to week between two different styles of homework. One style, which followed the standard practice that Baraniuk has used for years, consisted of one homework assignment per week, which was graded and returned the following week. The second style, which was called the “intervention,” incorporated three principles from cognitive science that have been shown to promote learning and increase long-term retention.The principles were implemented in the following way:Repeated retrieval practice — In addition to receiving the standard homework assignment, students were given follow-up problems on the same topic in two additional assignments that counted only toward their course participation grade. Spacing — Rather than giving all the problem sets for a week’s lectures in one assignment, the researchers spaced the problems over three weeks of assignments. Feedback — Rather than waiting one week to learn how they did, students received immediate feedback on intervention homework, and they were required to view the feedback to get credit for the assignment. “Giving students multiple opportunities to practice retrieving and applying their knowledge on new problems is a very powerful way to promote learning, especially when this practice is spaced out over time,” said study co-author Elizabeth Marsh, associate professor of psychology and neuroscience at Duke. “Feedback also is critical to learning, and previous studies have shown that students will often skip looking at feedback.”To alleviate any concerns that individual differences in ability might skew the study results, the researchers split the class into two groups and assigned each group standard homework and intervention homework during alternating weeks; in any given week, half of the students were assigned to the intervention and half to the standard practice homework.The course covered 11 broad topics and approximately five core concepts per topic. …

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Stem cell study finds source of earliest blood cells during development

Hematopoietic stem cells are now routinely used to treat patients with cancers and other disorders of the blood and immune systems, but researchers knew little about the progenitor cells that give rise to them during embryonic development.In a study published April 8 in Stem Cell Reports, Matthew Inlay of the Sue & Bill Gross Stem Cell Research Center, and faculty member of the Department of Molecular Biology and Biochemistry, and Stanford University colleagues created novel cell assays that identified the earliest arising HSC precursors based on their ability to generate all major blood cell types (red blood cells, platelets and immune cells).This discovery of very early differentiating blood cells, Inlay said, may be very beneficial for the creation of HSC lines for clinical treatments. “The hope is that by defining a set of markers that will allow us to make purer, cleaner populations of these precursor cells, we’ll be able to reveal the key molecular events that lead to the emergence of the first HSCs in development.This could give us a step-by-step guide for creating these cells in a dish from pluripotent stem cell lines” added Inlay, who is an assistant professor of molecular biology & biochemistry at UC Irvine and conducted the study while a postdoctoral researcher in the Irving Weissman lab at Stanford.The work was performed in collaboration with Thomas Serwold, now an assistant professor in the Joslin Diabetes Center at Harvard Medical School.Story Source:The above story is based on materials provided by University of California – Irvine. Note: Materials may be edited for content and length.

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Mindfulness-based meditation helps teenagers with cancer

Mindfulness-based meditation could lessen some symptoms associated with cancer in teens, according to the results of a clinical trial intervention led by researchers at the University of Montreal and its affiliated CHU Sainte-Justine children’s hospital.Mindfulness-based meditation focuses on the present moment and the connection between the mind and body. Adolescents living with cancer face not only the physical symptoms of their condition, but also the anxiety and uncertainty related to the progression of the disease, the anticipation of physical and emotional pain related to illness and treatment, the significant changes implied in living with cancer, as well as the fear of recurrence after remission. Catherine Malboeuf-Hurtubise of the university’s Department of Psychology presented the findings today at the American Psychosomatic Society Meeting in San Francisco.The researchers asked 13 adolescents with cancer to complete questionnaires covering mood (positive and negative emotions, anxiety and depression), sleep and quality of life. The group was divided in two: a first group of eight adolescents were offered eight mindfulness-based meditation sessions and the remaining five adolescents in the control group were put on a wait-list. The eight sessions were 90 minutes long and took place weekly. After the last meditation session, patients from both groups filled out the same questionnaires a second time. “We analyzed differences in mood, sleep and quality of life scores for each participant and then between each group to evaluate if mindfulness sessions had a greater impact than the simple passage of time. We found that teenagers that participated in the mindfulness group had lower scores in depression after our 8 sessions. Girls from the mindfulness group reported sleeping better. We also noticed that they developed mindfulness skills to a greater extent than boys during the sessions,” Malboeuf-Hurtubise said. …

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Gene family that suppresses prostate cancer discovered

Cornell researchers report they have discovered direct genetic evidence that a family of genes, called MicroRNA-34 (miR-34), are bona fide tumor suppressors.The study is published in the journal Cell Reports, March 13.Previous research at Cornell and elsewhere has shown that another gene, called p53, acts to positively regulate miR-34. Mutations of p53 have been implicated in half of all cancers. Interestingly, miR-34 is also frequently silenced by mechanisms other than p53 in many cancers, including those with p53 mutations.The researchers showed in mice how interplay between genes p53 and miR-34 jointly inhibits another cancer-causing gene called MET. In absence of p53 and miR-34, MET overexpresses a receptor protein and promotes unregulated cell growth and metastasis.This is the first time this mechanism has been demonstrated in a mouse model, said Alexander Nikitin, a professor of pathology in Cornell’s Department of Biomedical Sciences and the paper’s senior author. Chieh-Yang Cheng, a graduate student in Nikitin’s lab, is the paper’s first author.In a 2011 Proceedings of the National Academy of Sciences paper, Nikitin and colleagues showed that p53 and miR-34 jointly regulate MET in cell culture but it remained unknown if the same mechanism works in a mouse model of cancer (a special strain of mice used to study human disease).The findings suggest that drug therapies that target and suppress MET could be especially successful in cancers where both p53 and miR-34 are deficient.The researchers used mice bred to develop prostate cancer, then inactivated the p53 gene by itself, or miR-34 by itself, or both together, but only in epithelium tissue of the prostate, as global silencing of these genes may have produced misleading results.When miR-34 genes alone were silenced in the mice, the mice developed cancer free. When p53 was silenced by itself, there were signs of precancerous lesions early in development, but no cancer by 15 months of age. When miR-34 and p53 genes were both silenced together, the researchers observed full prostate cancer in the mice.The findings revealed that “miR-34 can be a tumor-suppressor gene, but it has to work together with p53,” Nikitin said.In mice that had both miR-34 and p53 silenced concurrently, cancerous lesions formed in a proximal part of the prostrate ducts, in a compartment known to contain prostate stem cells. The early lesions that developed when p53 was silenced alone occurred in a distal part of the ducts, away from the compartment where the stem cell pool is located. This suggested there was another mechanism involved when p53 and miR-34 were jointly silenced.Also, the number of stem cells in mice with both p53 and miR-34 silenced increased substantially compared with control mice or mice with only miR-34 or p53 independently silenced.”These results indicated that together [miR-34 and p53] regulate the prostate stem cell compartments,” said Nikitin.This is significant, as cancer frequently develops when stem cells become unregulated and grow uncontrollably, he said.Researchers further found that p53 and miR-34 affect stem cell growth by regulating MET expression. In absence of p53 and miR-34, MET is overexpressed, which leads to uncontrolled growth of prostate stem cells and high levels of cancer in these mice.Future work will further examine the role of p53/miR-34/MET genes in stem cell growth and cancer. …

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Cosmetic treatment can open door to bacteria

Many people have ‘fillers’ injected into their facial tissue to give them ‘bee-stung lips’ or to smooth out their wrinkles. Unfortunately, a lot of cosmetic treatment customers experience unpleasant side effects in the form of tender subcutaneous lumps that are difficult to treat and which — in isolated cases — have led to lesions that simply will not heal. Research recently published by the University of Copenhagen now supports that, despite the highest levels of hygiene, this unwanted side effect is caused by bacterial infection.Injections of fillers were previously reserved exclusively for trauma treatment — when rebuilding a face disfigured in a traffic accident, for example. However, the jelly-like substances are increasingly being used in beauty treatments with the intention of making lips swell up and to erase the effects of ageing from the skin. Side effects in the form of stubborn, tender lumps or even lesions are becoming an increasing problem:”Previously, most experts believed that the side effects were caused by an auto-immune or allergic reaction to the gel injected. Research involving tissue from patients and mouse models has now shown that the disfiguring lesions are actually due to bacteria injected in connection with the cosmetic procedure. What is more, we have demonstrated that the fillers themselves act as incubators for infection, and all it takes is as few as ten bacteria to create an ugly lesion and a tough film of bacterial material — known as biofilm — which is impossible to treat with antibiotics,” says Morten Alhede, a postdoc at the Department of International Health, Immunology and Microbiology, University of Copenhagen.The results have just been published in the journal Pathogens and Disease.Biofilm is resistant to antibioticsTreatment with fillers is very common. According to the American Society for Aesthetic Plastic Surgery (ASAPS), treatment with products based on hyaluronic acid — such as Restylane — constitutes the second-most popular non-surgical cosmetic procedure in the United States. The precise figures for Denmark are not known, but there can be no doubt that the numbers are rising rapidly — and a rise in the number of treatments will inevitably make the side effects more evident.”Because a lot of cosmetic practitioners refuse to accept that side effects from filler procedures are caused by bacteria, claiming that such problems are caused by allergic reactions, the usual procedure has been to treat with steroids. This is actually the worst possible treatment because steroid injections exacerbate the condition and give the bacteria free rein. …

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Characterization of stink bug saliva proteins opens door to controlling pests

Brown marmorated stink bugs cause millions of dollars in crop losses across the United States because of the damage their saliva does to plant tissues. Researchers at Penn State have developed methods to extract the insect saliva and identify the major protein components, which could lead to new pest control approaches.”Until now, essentially nothing was known about the composition of stink bug saliva, which is surprising given the importance of these insects as pests and the fact that their saliva is the primary cause of feeding injury to plants and crop losses,” said Gary Felton, professor and head of the Department of Entomology. “Other than using synthetic pesticides, there have been few alternative approaches to controlling these pests. By identifying the major protein components of saliva, it now may be possible to target the specific factors in saliva that are essential for their feeding and, therefore, design new approaches for controlling stink bugs.”The team reported its results in PLOS ONE.According to Felton, stink bugs produce two types of saliva that are required for successful feeding. Watery saliva helps stink bugs to digest their food. Sheath saliva surrounds stink bugs’ mouthparts and hardens to prevent spillage of sap during feeding. The hardened “sheath” remains attached to the plant when the insect is finished feeding.”Unlike a chewing insect, which causes damage by removing plant tissue, stink bugs pierce plant tissue and suck nutrients from the plant,” said Michelle Peiffer, research support assistant. “During this process, stink bugs also deposit saliva onto the plant. The interaction between this saliva and the plant is what causes the cosmetic and physiological changes that make crops unmarketable.”To extract the two types of saliva from brown marmorated stink bugs, Felton and Peiffer first collected adult bugs from homes and fields in central Pennsylvania and maintained them in their laboratory.The researchers chilled the insects on ice. As the insects returned to room temperature, their watery saliva was secreted from the tips of their beaks. …

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Smokers’ brains biased against negative images of smoking

What if the use of a product influenced your perception of it, making you even more susceptible to its positive aspects and altering your understanding of its drawbacks? This is precisely what happens with cigarettes in chronic smokers, according to a recent study by the Institut universitaire en sant mentale de Montral and Universit de Montral.The study showed that chronic smokers have altered emotional reactions when they are exposed to negative and positive images associated with tobacco. “We observed a bias depending on how smoking is portrayed ,” explained Le-Anh Dinh-Williams, a student at the Centre de recherche de l’Institut universitaire en sant mentale de Montral and the study’s first author. “For example, the brains of the smokers in our study were more aroused by images that showed smoking in a positive light than by images that encouraged them to stop. They were also more affected by aversive non-smoking related images than by images of the specific negative consequences of smoking.”In Canada and the United States, approximately 20% of adults smoke cigarettes despite knowing its adverse effects. “We wanted to understand why knowing about the negative health impacts of tobacco does not prevent smokers from lighting up,” explained Ms. Dinh-Williams.Approximately 70% to 95% of smokers who quit their bad habit will, despite their best efforts, start smoking again within one year. “Many factors make it difficult for people to quit. Part of the explanation could certainly be because cigarettes ‘trick’ the brains of smokers,” stated Stphane Potvin, a co-author of the study and researcher at the Institut universitaire en sant mentale de Montral and Assistant Professor in the Department of Psychiatry at Universit de Montral. “Specifically, we discovered that the brain regions associated with motivation are more active in smokers when they see pleasurable images associated with cigarettes and less active when smokers are confronted with the negative effects of smoking.”Using neuroimaging techniques, the study researchers compared the emotional reactions of 30 smokers as they looked at aversive smoking-related images (e.g., lung cancer) compared to other aversive images (e.g., an old man on his deathbed) as well as appetitive smoking-related images.StatisticsSmokers have a 3 to 9 times greater risk of developing cancer, lung disease or heart problems. …

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Preschoolers can outsmart college students at figuring out gizmos

Preschoolers can be smarter than college students at figuring out how unusual toys and gadgets work because they’re more flexible and less biased than adults in their ideas about cause and effect, according to new research from the University of California, Berkeley, and the University of Edinburgh.The findings suggest that technology and innovation can benefit from the exploratory learning and probabilistic reasoning skills that come naturally to young children, many of whom are learning to use smartphones even before they can tie their shoelaces. The findings also build upon the researchers’ efforts to use children’s cognitive smarts to teach machines to learn in more human ways.”As far as we know, this is the first study examining whether children can learn abstract cause and effect relationships, and comparing them to adults,” said UC Berkeley developmental psychologist Alison Gopnik, senior author of the paper published online in the journal, Cognition.Using a game they call “Blickets,” the researchers looked at how 106 preschoolers (aged 4 and 5) and 170 college undergrads figured out a gizmo that works in an unusual way. They did this by placing clay shapes (cubes, pyramids, cylinders, etc), on a red-topped box to see which of the widgets — individually or in combination — could light up the box and play music. The shapes that activated the machine were called “blickets.”What separated the young players from the adult players was their response to changing evidence in the blicket demonstrations. For example, unusual combinations could make the machine go, and children caught on to that rule, while the adults tended to focus on which individual blocks activated the machine even in the face of changing evidence.”The kids got it. They figured out that the machine might work in this unusual way and so that you should put both blocks on together. But the best and brightest students acted as if the machine would always follow the common and obvious rule, even when we showed them that it might work differently,” wrote Gopnik in her forthcoming column in The Wall Street Journal.Overall, the youngsters were more likely to entertain unlikely possibilities to figure out “blicketness.” This confirmed the researchers’ hypothesis that preschoolers and kindergartners instinctively follow Bayesian logic, a statistical model that draws inferences by calculating the probability of possible outcomes.”One big question, looking forward, is what makes children more flexible learners — are they just free from the preconceptions that adults have, or are they fundamentally more flexible or exploratory in how they see the world?” said Christopher Lucas, lead author of the paper and a lecturer at the University of Edinburgh. “Regardless, children have a lot to teach us about learning.”Other co-authors of the study are Thomas Griffiths and Sophie Bridgers of the UC Berkeley Department of Psychology.A new study shows children can sometimes outsmart grownups when it comes to figuring out how gadgets work because they’re less biased in their ideas about cause and effect. (Video by Roxanne Majasdjian and Philip Ebiner) http://www.youtube.com/watch?v=bHQ0DemKcEAStory Source:The above story is based on materials provided by University of California – Berkeley. The original article was written by Yasmin Anwar. …

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