Children raised without a father are at greater risk of deviant behavior later—and girls in particular may be more likely to abuse drugs and alcohol—according to a new study with mice.
While many studies have outlined the value of a mother, few have clearly defined the importance of a father. Researchers say this is the first study to link father absenteeism with social attributes and to correlate these with physical changes in the brain.Related Articles On Futurity
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“Although we used mice, the findings are extremely relevant to humans,” says senior author Gabriella Gobbi, associate professor of medicine at McGill University and a researcher of the Mental Illness and Addiction Axis at the Research Institute of the McGill University Health Center.
“We used California mice which, like in some human populations, are monogamous and raise their offspring together.”
“Because we can control their environment, we can equalize factors that differ between them,” says first author Francis Bambico, a former student of Gobbi’s who is now a postdoc at the Centre for Addiction and Mental Health in Toronto.
“Mice studies in the laboratory may therefore be clearer to interpret than human ones, where it is impossible to control all the influences during development.”Missing dads, aggressive kids
For the study, published in the journal Cerebral Cortex, researchers compared the social behavior and brain anatomy of mice that had been raised with both parents to those that had been raised only by their mothers.
Mice raised without a father had abnormal social interactions and were more aggressive than counterparts raised with both parents. These effects were stronger for female offspring than for their brothers. Females raised without fathers also had a greater sensitivity to the stimulant drug, amphetamine.
“The behavioral deficits we observed are consistent with human studies of children raised without a father,” Gobbi says. “These children have been shown to have an increased risk for deviant behavior and, in particular, girls have been shown to be at risk for substance abuse. This suggests that these mice are a good model for understanding how these effects arise in humans.”
Pups deprived of fathers also showed defects in the prefrontal cortex, a part of the brain that helps control social and cognitive activity, which is linked to the behavioral deficits.
“This is the first time research findings have shown that paternal deprivation during development affects the neurobiology of the offspring,” Gobbi says.
The results should incite researchers to look more deeply into the role of fathers during critical stages of growth and suggest that both parents are important in children’s mental health development.
Source: McGill University
Scientists have discovered why a select few newborn neurons survive, while most die before they can help with cognition, memory, or the regulation of mood.
The findings have wide implications for people with neurodegenerative conditions, such as dementia or Alzheimer’s disease, and perhaps for patients with brain damage, researchers say.Related Articles On Futurity
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Published in the journal, Nature Neuroscience, the new study shows how specific brain cells communicate with each other during adult neurogenesis—the creation of new neurons. One cell type—PV+ interneurons—can be stimulated to help baby neurons survive and thrive even as older neurons die.
“We now know how newborn neurons can be regenerated in specific regions of the brain,” says Juan Song, assistant professor of pharmacology at the University of North Carolina at Chapel Hill and the UNC Neuroscience Center.
“By showing how interneurons are a part of neurogenesis, we can see how it’s possible to regenerate cells in parts of the brain that are damaged, for example, because of a stroke.”
Neurogenesis, which occurs throughout the brain during pre-natal development, continues throughout adulthood in just two brain regions—the hippocampus and subventricular zone.Neurons grow up
It works like this: neural stem cells produce progenitor cells, more than half of which die within four days. The progenitor cells don’t have axons or dendrites—the cell parts that adult neurons use to create and transmit signals to each other.
The surviving progenitor cells—also known as newborn or baby neurons—then turn into immature neurons; these do form axons and dendrites and evolve into mature neurons that connect with other neurons through synapses. These mature neurons then integrate into the complex neural networks involved in cognition, memory, and mood.
Previously, when Song was a postdoctoral fellow at Johns Hopkins University, she studied how stem cells create neurons. She showed how neural stem cells “sense” the transmission of chemical signals between mature neurons and PV+ interneurons.
Song’s team used words such as “sensed,” “listened,” and “eavesdropped” because they found that the stem cells did not form synaptic connections with either the mature neurons or the interneurons.
They somehow “heard” the chemical signaling between the two other cell types. And depending on the signal, the stem cells either stayed dormant or began creating progenitor cells.
Because Song found that the stem cells weren’t physically connected to interneurons or mature neurons, she thought that the stem cell progeny—the newborn neurons—might also “sense” the chemical communication between mature neurons and interneurons.
But that’s not what she found.
Using mouse models and electron microscopy, Song discovered that PV+ interneurons attach their tail-like axons to newborn progenitor cells to form a synapse. Across that synaptic connection, the interneurons send chemical signals.
When Song stimulated the interneurons with a beam of light or mild electrical signals, the baby neurons lived longer than they did without stimulation.
“The progenitors survived,” Song says. “They evolved into new neurons. So, this stimulation created more neurogenesis in the adult brains of mice.”Role of exercise
It’s unclear how such stimulation translates into human activity. For instance, exercise has been found to trigger the creation of neurons in mice. And exercise in adults has shown to improve brain function.
But it isn’t clear that the creation of new neurons always causes improved brain function. Also, it isn’t clear that the lack of exercise—both physical and perhaps cognitive—slows down neurogenesis as we age.
Still, Song’s research is the first to show that simulating a specific cell type does indeed spur on neurogenesis. The finding underscores the importance of a specific cell type—PV+ interneurons—in the creation of new neurons, and it offers researchers another route to finding therapies for degenerative conditions and even brain disorders, such as schizophrenia.
“I think our study could be extended to look directly at behaviors in mouse models of neurological diseases. We would be able to see if behaviors are linked to interneurons and neurogenesis.”
For now, Song’s lab is still uncovering the mysteries of neurogenesis in normal animal models. For instance, scientists aren’t sure exactly how stem cells “sense” the communication between interneurons and mature neurons.
They also don’t know if simply stimulating interneurons causes stem cells to give birth to progenitor cells or if something more complicated is going on. Song is studying that now.
Her team also wants to study exactly how interneurons become attached to progenitor cells; how do interneurons “find” the baby neurons to communicate with them?
“Right now, we don’t know. Our working hypothesis is that new neurons are born into a mesh of interneuron terminals. And we think the newborn neurons possess chemical signals that guide the interneurons, which then attach to the newborn neurons.
“It would be interesting to see if the newborn neurons that lack this synaptic connection are the same ones that die before becoming mature neurons.”
Source: UNC-Chapel Hill
The spotted wing drosophila, a major pest that attacks berries and cherries and other fruits, is being targeted by scientists via an open access genome database.
The genome study, published in the journal G3: Genes, Genomics, Genetics, is expected to accelerate basic and applied research, leading to better monitoring and control strategies for the pest.
“To enable basic and applied research of this important pest, Drosophila suzukii, we sequenced the genome to obtain a high-quality reference sequence,” says molecular geneticist Joanna Chiu of the UC Davis Department of Entomology and Nematology. Chiu and Professor David Begun of the UC Davis Department of Evolution and Ecology led the genomics team of collaborative researchers from four institutions.Related Articles On Futurity
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The posting of the genome and comparative sequence analysis on the publicly accessible SpottedWingFlyBase web portal could lead to more species-specific weapons to combat the destructive pest, Chiu says. Scientists are looking at its biology, behavior, food and odor preferences, and pesticide resistance.
“Many researchers are working hard to study the biology of this insect through basic and applied projects, and we hope our efforts in presenting our genomic data in a user-friendly Web portal will democratize the sequence data and help facilitate everyone’s research, especially those who do not have expertise in genome and sequence analysis,” she says.US newcomer
The spotted wing drosophila, a native of Asia that was first detected in the United States in 2008, is wreaking economic havoc on crops such as blueberries, cherries, blackberries, and raspberries. This fly lays its eggs inside the ripe or ripening fruit, and the developing larvae feed on the soft fruit, crippling crop yields.
The spotted wing drosophila is a vinegar fly about 1/16 to 1/8 inch long with red eyes, pale brown thorax, and a black-striped abdomen. The males have a distinguishing black spot toward the tip of each wing. Females have no spots but have a prominent, saw-like ovipositor for drilling fruit to lay their eggs.
Chiu teamed with scientists at UC Davis, Oregon State University, the China National Gene Bank, and the American Museum of Natural History as part of a $5.8 million project on the biology and management of spotted wing drosophila.
Frank Zalom, professor in the UC Davis Department of Entomology and Nematology, says that the G3 article “presents a high-quality reference sequence of Drosophila suzukii, examination of the basic properties of its genome and transcriptome, and description of patterns of genome evolution in relation to its close relatives.”
Oregon State University entomologist Vaughn Walton, lead investigator says: “Scientists from all over the world are interested in knowledge locked inside the fly’s genetic material.” He also points out that the genome work may relieve the fears of countries wishing to import American fruit, but not the pest. By finding the fly’s unique genetic signature, scientists hope that DNA testing will quickly determine if ready-to-be-shipped fruit contains spotted wing drosophila larvae.
A US Department of Agriculture Specialty Crops Research Initiative grant funded the research.
Source: UC Davis
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A new medical device to treat epilepsy works like a cardiac defibrillator to detect and suppress seizures the instant they begin.
Clinical trials of the Responsive Neurostimulator System (RNS) show that the device decreases the number of monthly seizures by nearly 38 percent. The device received approval from the Food and Drug Administration on Nov. 14.Related Articles On Futurity
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“This is the first FDA-approved brain implant for epilepsy that responds to the brain’s activity,” says Michel Berg, an associate professor of neurology at the University of Rochester Medical Center.
“For patients who are unable to control their seizures with medications or are not eligible for resective surgery, this device could provide an important treatment option.”
An estimated three million Americans suffer from epilepsy. The condition, which can be triggered by a host of different factors, results in bursts of electrical activity in the brain caused when groups of neurons fire in an abnormal pattern. The resulting seizures can vary in length and severity.
While most individuals with the condition are able to manage their symptoms with one or more antiepileptic drugs, for a significant portion of people with epilepsy these medications are either not effective or result in intolerable side effects. Some of these patients are candidates for surgery, which removes the region of the brain where the seizures originate.Like a cardiac defibrillator
However, when the seizures come from several different spots or are located in an area of the brain that serves an important function, such as language processing or motor control, resective surgery is not possible. For patients who have run out of traditional medical options, the device may be an effective way to control their seizures.
The implantable device is designed to suppress seizures before symptoms appear. The device functions in a manner akin to implantable cardiac defibrillators, which detect abnormal heart rhythms and then deliver electrical stimulation to correct them.
The RNS is surgically implanted under the scalp and connected to one or two leads—insulated wires with electrodes at the end—that are placed either on the surface of the brain or are guided into the brain in the area where the seizures are determined to originate.
It continuously monitors the patient’s brain waves and when seizure activity is detected, the device instantly delivers a mild, brief electrical stimulation that suppresses the seizures.
“The RNS system is not only a technological breakthrough, but the device is an important new tool that could help patients control their seizures and, ultimately, improve their quality of life,” says James Fessler, director of URMC’s Strong Epilepsy Center.
Source: University of Rochester
People who graduate from college during a recession are ultimately more satisfied with their jobs, according to a new study.
The findings appear in Administrative Science Quarterly.
Emily Bianchi, assistant professor of organization and management at Emory University’s Goizueta Business School, analyzed data from two large government-run surveys that have been administered regularly since the 1970s.Related Articles On Futurity
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The results showed that people who earned their degrees during economic downturns were more satisfied with their current jobs than those who first looked for work during more prosperous economic times.
According to Bianchi, the results could not be accounted for by generational differences or differences in industry or occupational selection.
The findings are particularly surprising given the well-documented negative financial aspects of graduating in a recession. Recession graduates earn less money and often hold less prestigious jobs.
Bianchi argues that how people evaluate what they have does not always reflect the value of what they have. As she writes, “Decades of psychological research has shown that how people feel about their outcomes does not always mirror the objective value of these outcomes.” People can be happy with less, depending on how they think about their outcomes.
Conversely, people who graduate in economic booms are more likely to wonder if they could have done better and ruminate over paths not taken, says Bianchi. In contrast, recession graduates are more likely to feel grateful to have a job at all and spend less time wondering how they might have done better.
Graduates’ initial ways of thinking about work tends to endure. Bianchi found that recession graduates were typically more pleased with their jobs both early in their careers and even decades later. The earlier trials of their career seemed to positively influence their evaluations of later jobs.
Bianchi argues that this conclusion is consistent with recent research in psychology that reveals that some adversity is associated with greater happiness than either too much or too little.
“Too much adversity can be emotionally debilitating. Too little can weaken resilience, allowing people to magnify and exaggerate the bumps of everyday life,” explains Bianchi.
Source: Emory University
Models of how proteins fold—and sometimes misfold—reveal branching behavior that may have implications for Alzheimer’s and other aggregation diseases.
In an earlier study of the muscle protein titin, Rice University chemist Peter Wolynes and his colleagues analyzed the likelihood of misfolding in proteins, in which domains—discrete sections of a protein with independent folding characteristics—become entangled with like sequences on nearby chains.Related Articles On Futurity
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They found the resulting molecular complexes called “dimers” were often unable to perform their functions and could become part of amyloid fibers.
This time, Wolynes and his co-authors, postdoctoral researcher Weihua Zheng and graduate student Nicholas Schafer, modeled constructs containing two, three, or four identical titin domains.
They discovered that rather than creating the linear connections others had studied in detail, these proteins aggregated by branching; the proteins created structures that cross-linked with neighboring proteins and formed gel-like networks that resemble those that imbue spider silk with its remarkable flexibility and strength.
“We’re asking with this investigation, ‘What happens after that first sticky contact forms?’” Wolynes says. “What happens if we add more sticky molecules? Does it continue to build up further structure out of that first contact?
“It turned out this protein we’ve been investigating has two amyloidogenic segments that allow for branch structures. That was a surprise,” he says.
Results from the research appear online in the Proceedings of the National Academy of Sciences.‘Minimal frustration’ principle
The researchers used their AWSEM (Associative memory, Water-mediated Structure and Energy Model) program to analyze how computer models of muscle proteins interact with each other, particularly in various temperatures that determine when a protein is likely to fold or unfold.
The program relies on Wolynes’s groundbreaking principle of minimal frustration to determine how the energy associated with amino acids, bead-like elements in a monomer chain, determines their interactions with their neighbors as the chain folds into a useful protein.
Proteins usually fold and unfold many times as they carry out their tasks, and each cycle is an opportunity for it to misfold. When that happens, the body generally destroys and discards the useless protein. But when that process fails, misfolded proteins can form the gummy amyloid plaques often found in the brains of Alzheimer’s patients.
The titin proteins the team chose to study are not implicated in disease but have been well-characterized by experimentalists, which gives the researchers a solid basis for comparison.
“In the real muscle protein, each domain is identical in structure but different in sequence to avoid this misfolding phenomenon,” Wolynes says. So experimentalists studying two-domain constructs made the domains identical in every way to look for the misfolding behavior that was confirmed by earlier calculations. That prompted Wolynes and his team to create additional protein models with three and four identical domains.
“The experiments yield coarse-grained information and don’t directly reveal detail at the molecular level,” Schafer says. “So we design simulations that allow us to propose candidate misfolded structures.
“This is an example of how molecular models can be useful for investigating the very early stages of aggregation that are hard to see in experiments, and might be the stages that are the most medically relevant.”Look for branching
“We want to get the message across that this is a possible scenario for misfolding or aggregation cases—that this branching does exist,” Zheng adds. “We want experimentalists to know this is something they should be looking for.”
Wolynes says the lab’s next task is to model proteins that are associated with specific diseases to see what might be happening at the start of aggregation. “We have to investigate a wider variety of structures,” he says. “We have no new evidence these branching structures are pathogenic, but they’re clearly an example of something that happens that has been ignored until now.
“I think this opens up new possibilities in what kind of structures we should be looking at,” he says.
The National Institute of General Medical Sciences, one of the National Institutes of Health, and the D.R. Bullard-Welch Chair at Rice University supported the research. The researchers utilized the Data Analysis and Visualization Cyberinfrastructure (DAVinCI) supercomputer supported by the National Science Foundation and administered by Rice’s Ken Kennedy Institute for Information Technology.
Source: Rice University
Ten years after a transplant, a cornea from a 71-year-old donor is likely to remain as healthy as a cornea from a donor half that age, according to a new long-term study.
In the US, three-fourths of cornea donors are within the 34- to 71-age range, with one-third of donors at the upper end of the range, from 61 to 70 years old. When the study began in 2000, many surgeons would not accept corneas from donors over 65.
The Cornea Donor Study found that 10-year success rates remained steady at 75 percent for corneal transplants from donors 34 to 71 years old. It also found slightly higher success rates for donors under 34, and somewhat lower rates for donors over 71. The results were published online in Ophthalmology and presented in New Orleans at a joint meeting of the Eye Bank Association of America and the Cornea Society.Related Articles On Futurity
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“The findings clearly demonstrate that most corneal transplants have remarkable longevity regardless of donor age,” says Mark Mannis, chair of ophthalmology and vision sciences, director of UC Davis Health System’s Eye Center and co-chair of the study. “The majority of patients continued to do well after 10 years, even those who received corneas from the oldest donors.”
The study “supports continued expansion of the corneal donor pool beyond age 65,” says study co-chair Edward J. Holland, professor of ophthalmology at the University of Cincinnati and director of the Cornea Service at the Cincinnati Eye Institute.Supply and demand
A corneal transplant is performed when decreased vision or discomfort from corneal damage cannot be corrected with lenses or medication. It involves removing a portion of the damaged cornea and grafting corneal tissue from a deceased donor in its place. More than 46,000 corneal transplants were performed in the United States last year. In addition, US eye banks exported about 20,000 corneas to other countries in 2012, an increase of 7 percent over 2011.
The supply of corneas does not meet the demand internationally, and as the aging population grows at home and abroad, the need for corneal transplants is expected to grow, too. The study was designed to address whether making use of donor corneas across the full range of ages available might help solve this problem,” says Maryann Redford, a clinical research program director at National Eye Institute.
The study compared graft survival rates for corneas from two donor age groups, aged 12 to 65 and aged 66 to 75. Coordinated by the Jaeb Center for Health Research, it involved 80 clinical sites across the US and enrolled 1,090 people aged 40 to 80 who were eligible for transplants.
Forty-three eye banks provided donor corneas, which met the quality standards of the Eye Bank Association of America. Patients received the corneas without respect to patient age using a transplant procedure called penetrating keratoplasty, in which the central part of the damaged cornea is removed, and a full-thickness donor cornea is sutured in its place.Eye disease
About two thirds of patients had an inherited corneal disease called Fuchs’ dystrophy, and one third had corneal swelling after cataract surgery. These conditions involve loss of cells in the innermost (endothelial) layer of the cornea and are leading reasons for corneal transplants reported to US eye banks. Graft failure was defined as the need for a new transplant, or a cloudy cornea that caused blurred vision for at least three months.
The investigators originally planned to follow patients for five years post-transplant. In 2008, they reported that the five-year success rate was identical—86 percent—for transplants from donors aged 12 to 65 and those aged 66 to 75. However, when the investigators examined endothelial cells in the transplanted corneas, they found that older corneas had a slightly higher rate of cell loss.
Higher cell loss at six months also predicted a higher likelihood of graft failure at five years. That prompted an expansion of the study to determine if donor age would affect transplant viability 10 years after the procedure.Findings at 10-year mark
During the follow up, 663 participants remained eligible and willing to continue with the study. The investigators report that at 10 years, the transplant success rates for corneas from donors aged 12 to 65 and aged 66 to 75 remained similar, at 77 percent and 71 percent, respectively. However, when the investigators separated the donors into smaller age groups, they found some differences. The success rate remained steady at 75 percent for the vast majority of donors ages 34 to 71. But it increased to 96 percent for donors age 12 to 33 and decreased to 62 percent for donors age 72 to 75.
The investigators also re-evaluated the endothelial cells lining the inner cornea in a subgroup of 176 patients who had a successful transplant at 10 years and for whom high-quality images of the cells were available. The data confirmed the trend in cell loss seen at five years. At 10 years, corneas from donors over age 65 had a slightly higher rate of endothelial cell loss (79 percent) compared to those from donors age 65 and under (76 percent). The youngest corneas, from donors age 12 to 33, had the highest number of cells before surgery and the lowest rate of cell loss at 10 years (67 percent).
“The cell loss data parallels the graft survival data, but we don’t yet know if a given number of cells at five years is predictive of graft failure at 10 years,” says Jonathan Lass, professor of ophthalmology at Case Western Reserve University and University Hospitals Case Medical Center in Cleveland and medical director of the study’s cornea image analysis reading center. That analysis is being done and will be released at a later date, he says.Evaluating transplant procedures
The investigators note that corneal surgeries have changed in the past decade. Penetrating keratoplasty was the standard procedure used for corneal transplants when the study was launched. But today, most patients with Fuchs’ dystrophy or corneal swelling undergo endothelial keratoplasty, which involves replacing only the endothelial layer rather than the entire central cornea. The ongoing Cornea Preservation Time Study, led by Lass, is examining the factors contributing to transplant success after endothelial keratoplasty.
In the meantime, the investigators say the current study provides the most comprehensive data on the relationship between donor age and corneal transplant outcome.Age matching
Given the high success rate for transplants involving young donors (under age 34), the investigators wrote that their analysis “raises the question . . . of whether age-matching of donors and recipients is appropriate at the extremes of recipient age.” Such age matching is already a frequent practice for children and other young patients in need of corneal transplants, who routinely get corneas from young donors. But young donor corneas are relatively rare. In 2012, corneal donors under age 31 comprised less than 10 percent of the US donor pool.
Surgeons often seek the youngest corneal tissue available regardless of patient age. Historically, some surgeons set extremely restrictive upper age limits, even refusing tissue from donors over age 50, Mannis says.
“The study demonstrates the viability of older donor tissue in the majority of cases with endothelial disease,” he says. “In time, we hope the study will have a lasting impact on the practice of corneal transplant surgery. Although the results suggest that age-matching may be appropriate for the very youngest donors and patients, we do not think it is necessary in the vast majority of cases.”
The National Eye Institute funded the research. The Eye Bank Association of America, Bausch & Lomb, Tissue Banks International, Vision Share, San Diego Eye Bank, The Cornea Society, Katena Products, ViroMed Laboratories, Midwest Eye-Banks, Konan Medical Corp., Eye Bank for Sight Restoration, SightLife, Sight Society of Northeastern New York, and Lions Eye Bank of Oregon provided additional support.
Source: UC Davis
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A new way to block the transportation of sperm during ejaculation may lead to a contraceptive for men.
Scientists say that complete male infertility could be achieved by blocking two proteins found on the smooth muscle cells that trigger the transport of sperm.Related Articles On Futurity
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As reported in the Proceedings of the National Academy of Sciences, researchers demonstrated that the absence of two proteins in mouse models, α1A-adrenoceptor and P2X1-purinoceptor, which mediate sperm transport, caused infertility, without effects on long-term sexual behavior or function.
The finding could be applied to the potential development of a contraceptive pill for men, researchers say.
“Previous strategies have focused on hormonal targets or mechanisms that produce dysfunctional sperm incapable of fertilization, but they often interfere with male sexual activity and cause long term irreversible effects on fertility,” says Sab Ventura of the Monash Institute of Pharmaceutical Sciences.Infertility without side effects
“We’ve shown that simultaneously disrupting the two proteins that control the transport of sperm during ejaculation causes complete male infertility, but without affecting the long-term viability of sperm or the sexual or general health of males. The sperm is effectively there but the muscle is just not receiving the chemical message to move it.
There is already a drug that targets one of the two proteins, but researchers will have to find a chemical and develop a drug to block the second one.
“This suggests a therapeutic target for male contraception,” Ventura says. “The next step is to look at developing an oral male contraceptive drug, which is effective, safe, and readily reversible.”
If successful, researchers hope a male contraceptive pill could be available within ten years.
Researchers from University of Melbourne and the University of Leicester collaborated on the study.
Source: Monash University
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An ocean below the surface of Jupiter’s moon Europa may have deep currents and circulation patterns with heat and energy transfers that are capable of sustaining life.
Scientists believe Europa is one of the planetary bodies in our solar system most likely to have conditions that could sustain life, an idea reinforced by magnetometer readings from the Galileo spacecraft detecting signs of a salty, global ocean below the moon’s icy shell.Related Articles On Futurity
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Without direct measurements of the ocean, scientists have to rely on magnetometer data and observations of the moon’s icy surface to account for oceanic conditions below the ice.
Regions of disrupted ice on the surface, known as chaos terrains, are one of Europa’s most prominent features. They’re concentrated in the moon’s equatorial region and could result from convection in its ice shell, accelerated by heat from the ocean.
Scientists say the heat transfer and possible marine ice formation may be helping form diapirs—warm compositionally buoyant plumes of ice that rise through the shell.
As reported in the journal Nature Geosciences, a numerical model of Europa’s ocean circulation shows that warm rising ocean currents near the equator and subsiding currents in latitudes closer to the poles could account for the location of chaos terrains and other features of Europa’s surface.
Such a pattern coupled with regionally more vigorous turbulence intensifies heat transfer near the equator, which could help initiate upwelling ice pulses that create features such as the chaos terrains.‘Ice giant’ oceans
“The processes we are modeling on Europa remind us of processes on Earth,” says Krista Soderlund, of the Institute for Geophysics at University of Texas at Austin, where a similar process has been observed in the patterns creating marine ice in parts of Antarctica.
The current patterns modeled for Europa contrast with the patterns observed on Jupiter and Saturn, where bands of storms form because of the way their atmospheres rotate. The physics of Europa’s ocean appear to have more in common with the oceans of the “ice giants” Uranus and Neptune, which show signs of three-dimensional convection.
“This tells us foundational aspects of ocean physics,” notes co-author Britney Schmidt, assistant professor at the Georgia Institute of Technology. More importantly, if the study’s hypothesis is correct, it shows that Europa’s oceans are very important as a controlling influence on the surface ice shell, offering proof of the concept that ice-ocean interactions are important to Europa.
“That means more evidence that the ocean is there, that it’s active, and there are interesting interactions between the ocean and ice shell,” says Schmidt, “all of which makes us think about the possibility of life on Europa.”
Soderlund, who has studied icy satellites throughout her science career, looks forward to the chance to test her hypothesis through future missions to the Jovian system.
The European Space Agency’s JUICE mission (JUpiter ICy moons Explorer) will give a glimpse into the characteristics of the ocean and ice shell through two flyby observations. NASA’s Europa Clipper mission concept, under study, would complement the view with global measurements.
Research funding was provided by the Institute for Geophysics, part of The University of Texas at Austin’s Jackson School of Geosciences.
Source: University of Texas at Austin
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Previous explanations have suggested that the stars that form the bulge at the center of our galaxy are in banana-like orbits, but a new paper suggests the stars probably move in orbits shaped like peanut shells or figures of eight.
The difference is important because astronomers develop theories of star motions to not only understand how the stars in our galaxy are moving today but also how our galaxy formed and evolves.
The Milky Way is shaped like a spiral, with a region of stars at the center known as the “bar,” because of its shape. In the middle of this region, there is a “bulge” that expands out vertically.Related Articles On Futurity
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In the new paper published in Monthly Notices of the Royal Astronomical Society, scientists have created a mathematical model of what might be happening at the center of the Milky Way.
Unlike the Solar System where most of the gravitational pull comes from the Sun and is simple to model, it is much harder to describe the gravitational field near the center of the galaxy, where millions of stars, vast clouds of dust, and even dark matter swirl about.
In this case, Alice Quillen, professor of astronomy at the University of Rochester, and her collaborators considered the forces acting on the stars in or near the bulge.Like a child on a swing
As the stars go round in their orbits, they also move above or below the plane of the bar. When stars cross the plane they get a little push, like a child on a swing. At the resonance point, which is a point a certain distance from the center of the bar, the timing of the pushes on the stars is such that this effect is strong enough to make the stars at this point move up higher above the plane.
It is like when the child on the swing has been pushed a little every time he comes round and eventually he is swinging higher. These stars that are pushed out form the edge of the bulge.
The resonance at this point means that stars undergo two vertical oscillations for every orbital period. But what is the most likely shape of the orbits in between?
The researchers showed through computer simulations that peanut-shell shaped orbits are consistent with the effect of this resonance and could give rise to the observed shape of the bulge, which is also like a peanut-shell.
Later this month the European Space Agency will launch the Gaia spacecraft, which is designed to create a 3D map of the stars in the Milky Way and their motions. This 3D map will help astronomers better understand the composition, formation, and evolution of our galaxy.
“It is hard to look back into the past of our galaxy and know what was there, but simulations can give us clues,” explains Quillen. “Using my model I saw that, over time, the resonance with the bar, which is what leads to these peculiarly shaped orbits, moves outwards. This may be what happened in our galaxy.”
Quillen says Gaia will generate “huge amounts of data—on billions of stars.” This data will allow Quillen and her colleagues to finesse their model further.
“This can lead to a better understanding of how the Milky Way might have evolved into the shape it has today.”Stars in the bar
Quillen says that there are different models as to how the galactic bulge was formed. Astronomers are interested in finding out how much the bar has slowed down over time and whether the bulge “puffed up all at once or slowly.” Understanding the distributions of speeds and directions of motion (velocities) of the stars in the bar and the bulge might help determine this evolution.
“One of the predictions of my model is that there is a sharp difference in the velocity distributions inside and outside the resonance,” Quillen says. “Inside—closer to the galactic center—the disk should be puffed up and the stars there would have higher vertical velocities. Gaia will measure the motions of the stars and allow us to look for variations in velocity distributions such as these.”
To be able to generate a model for the orbits of stars in the bulge, Quillen needed to factor in different variables. She first needed to understand what happens at the region of the resonance, which depends on the speed of the rotating bar and the mass density of the bar.
“Before I could model the orbits, I needed the answer to what I thought was a simple question: what is the distribution of material in the inner galaxy?” Quillen says. “But this wasn’t something I could just look up. Luckily my collaborator Sanjib Sharma was able to help out.”
Sharma worked out how the speed of circular orbits changed with distance from the galactic center (called the rotation curve). Using this information, Quillen could compute a mass density at the location of the resonance, which she needed for her model.
Quillen was also able to combine the new orbit models with the speed of the bar (which is rotating) to get a more refined estimate of the mass density 3000 light years from the Galaxy center (about one eighth of the distance from the center of the Galaxy to Earth), which is where the edge of the bulge is.
And there is not long now to wait now for Gaia to start collecting data. Gaia’s launch time is set for December 19, and will be streamed live on the ESA Portal.
Researchers from the Sydney Institute for Astronomy, Australia; Astronomy Institute of Potsdam, Germany; Shanghai Astronomical Observatory, China; and Paris-Meudon Observatory, France, collaborated on the study.
Source: University of Rochester
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A smartphone game called “Airport Scanner” shows that finding weapons and other illegal items isn’t all that easy, even when you’re looking for them.
Researchers analyzed data from searches of 20 million virtual suitcases in the game, created by Kedlin Co., and found that users failed in most cases to identify objects that occurred only rarely.
“We’re seeing that people are really bad at finding items that are not likely to appear,” says Stephen Mitroff, associate professor of psychology and neuroscience and member of the Duke Institute for Brain Sciences.
In the game, players scan images that look like X-rays of carry-on luggage, trying to find hundreds of possible items, including guns and dynamite sticks, as well as over-sized bottles and scissors.‘Ultra-rare’ items
For this study—which appears online in Psychological Science—researchers evaluated gameplay data from December 2012 to March 2013 to determine how often the players found 78 different illegal items in light of how often the items appeared. Investigators used target frequencies (the appearance rate of a specific illegal object) to understand a player’s success at identifying targets when they appear.Related Articles On Futurity
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Thirty items were “ultra-rare,” appearing in the game less than 0.15 percent of the time—a rate that is comparable to the presence of cancerous markers in real-life radiological screenings, according to Mitroff.
Yet the study results revealed players correctly identified those 30 targets only 27 percent of the time. Targets that appeared with more than 1 percent frequency were pinpointed 92 percent of the time.
“This isn’t a matter of overall vigilance or how frequently players responded, since half of the searches had a to-be-found item present,” Mitroff says. “This effect is about being able to detect specific items and how likely you are to miss them when they occur infrequently.”Common, but minor, threats
For example, airport screeners are more likely to encounter pocketknives or incorrectly packed prescription medications than they are to see a gun in a carry-on bag. So, they might become conditioned to catch the illegal, though relatively harmless, items that appear more frequently than a rarely seen weapon.
“With the very large array of potential targets, the searchers seem to be highly sensitive to how frequently each individual target appeared, and they adjusted the focus of their searches so that targets that appeared rarely were a low priority,” Mitroff says. “This situation may be what occurs in many real-world searches.”
This research is important, Mitroff says, because it explores how rare objects slip past us no matter how hard we’re looking for them or how critical finding them might be, something he and co-author Adam Biggs, a post-doctoral researcher from the psychology and neuroscience department in the Center for Cognitive Neuroscience, have termed the “ultra-rare item effect.”
The strong relationship between the frequencies and associated detection rates surprised Mitroff’s team even though they anticipated a connection. Based on these results, Mitroff says, the door is open to further research into how behaviors can be modified to catch more ultra-rare items.TSA training?
The potential is also there, Mitroff says, for the Airport Scanner game to play a role in Transportation Security Administration training and standard operating procedures. The research team now has access to more than 1.5 billion trials from the smartphone app for analysis.
“We want to better understand why this happens.” he says. “Are you attuned to more frequent items at the cost of others? If you don’t see something very often, it makes sense that you don’t want to waste energy looking for it, but at the end of the day you still want to detect some of these ultra-rare items.”
The anonymous game data were shared in accordance with the Standard Apple User agreement, and Duke University approved the analysis of the data. This research received no external funding support.
Source: Duke University
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If you carry a smartphone, the world can spy on you.
Surveillance is a fundamental part of the cellular network, writes Stephen Wicker in his new book Cellular Convergence and the Death of Privacy. But Wicker says there are ways to change the system and to reclaim privacy.
The term “cellular convergence” refers to the fact that more and more of our activities are being managed through that little flat box. That’s “wonderful,” says Wicker, a professor of electrical and computer engineering at Cornell University, “but we must be aware that cellular is also a surveillance technology.”
The book was written before the current eruption of criticism over spying by the National Security Agency (NSA) but, Wicker says, “The NSA has simply been caught taking advantage of the vulnerabilities that I discuss in the book. [The publicity] gives us a chance to have an open democratic debate about the surveillance.”
To route incoming calls to the handset, the phone company keeps track of the cell towers that are nearby. Location-based apps keep even more refined data, constantly triangulating from cell towers and reading GPS location information.
To monitor performance it logs that data, and thanks to recent court decisions it can make the logs available to law enforcement without a warrant.
Service providers might also sell the data to commercial enterprises to use in targeting advertisements, and not just the ones that invite you to a restaurant nearby. Knowing where you go, down to the level of street addresses, can reveal a lot: your job, your religion, food preferences, what kind of car you drive, where your kids go to school, and which medical specialists you visit, to name just a few possibilities.
The lack of concern over “metadata,” Wicker says, ignores the vast amount of information context can reveal.
In one notorious case, hidden software on millions of phones logged text messages, Google searches, and phone numbers dialed.
“The amount of data that is being collected is astonishing and problematic,” Wicker writes. “Were the data simply thrown away after being used to route calls or improve network performance, I would not be writing this book.”Chilling effect
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After explaining the technology, Wicker reviews the tangled history of communications law and politics, from the wiretapping of early telegraph lines to the Patriot Act passed after the September 11 attacks, which required communications providers to collect and store an array of information and make it available to the government.
Along with eroding privacy, he adds, government action or inaction has seriously slowed the progress of cellular communications.
He draws on philosophers and psychologists to argue that privacy is a “right,” because it is essential to the development of personality. And while mobile phones have vastly expanded the potential for personal expression, he points out, the ever-present possibility of surveillance can have a chilling effect.
Finally, he proposes two ways to limit electronic intrusion:
- Encryption of the data we send over the system.
- “Simply starting from scratch” by redesigning the system: make location data less precise and let the handset make decisions about where and how messages are routed, similar to the way messages are sent “end to end” on the Internet. Phones could also use increasingly ubiquitous Wi-Fi to bypass cell towers altogether.
“It is time to remove the impediments and let cellular technology achieve its full promise,” Wicker writes.
Source: Cornell University
Scientists have finally turned human stem cells into functioning lung cells, and say the breakthrough paves the way for using a patient’s own cells for lung transplant.
“Researchers have had relative success in turning human stem cells into heart cells, pancreatic beta cells, intestinal cells, liver cells, and nerve cells, raising all sorts of possibilities for regenerative medicine,” says study leader Hans-Willem Snoeck, professor of medicine at Columbia University. “Now, we are finally able to make lung and airway cells. This is important because lung transplants have a particularly poor prognosis.
“Although any clinical application is still many years away, we can begin thinking about making autologous lung transplants—that is, transplants that use a patient’s own skin cells to generate functional lung tissue.”Complete the transformation
The research builds on Snoeck’s 2011 discovery of a set of chemical factors that can turn human embryonic stem (ES) cells or human induced pluripotent stem (iPS) cells into anterior foregut endoderm—precursors of lung and airway cells.
Human iPS cells closely resemble human ES cells but are generated from skin cells, by coaxing them into taking a developmental step backwards. Human iPS cells can then be stimulated to differentiate into specialized cells—offering researchers an alternative to human ES cells.
In the current study, published in the journal Nature Biotechnology, Snoeck and colleagues found new factors that can complete the transformation of human ES or iPS cells into functional lung epithelial cells—cells that cover the lung surface.
The resultant cells were found to express markers of at least six types of lung and airway epithelial cells, particularly markers of type 2 alveolar epithelial cells. Type 2 cells are important because they produce surfactant, a substance critical to maintain the lung alveoli, where gas exchange takes place; they also participate in repair of the lung after injury and damage.New drugs and transplants
The findings have implications for the study of a number of lung diseases, including idiopathic pulmonary fibrosis (IPF), in which type 2 alveolar epithelial cells are thought to play a central role.
“No one knows what causes the disease, and there’s no way to treat it,” says Snoeck. “Using this technology, researchers will finally be able to create laboratory models of IPF, study the disease at the molecular level, and screen drugs for possible treatments or cures.”
“In the longer term, we hope to use this technology to make an autologous lung graft,” Snoeck adds. “This would entail taking a lung from a donor; removing all the lung cells, leaving only the lung scaffold; and seeding the scaffold with new lung cells derived from the patient. In this way, rejection problems could be avoided.”
Columbia University has filed for a patent relating to the generation of lung and airway epithelium from human pluripotent stem cells and uses thereof. The authors declare no other financial or other conflicts of interests.
Funds from Columbia University and the New York Stem Cell Foundation supported the work.
Source: Columbia University
Culling vampire bat colonies to fight rabies in Latin America does little to slow the spread of the virus—and could even have the reverse effect.
Vampire bats transmit rabies virus throughout Latin America, causing thousands of livestock deaths each year, as well as occasional human fatalities. Poison and even explosives have been used since the 1960s in attempts to control vampire bat populations, but those efforts have generally failed.Related Articles On Futurity
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Researchers combined field findings from an earlier study with new computer models of rabies transmission and data from infection studies using captive vampire bats and found that culling has minimal effect on containing the virus, and can, in some cases, actually increase its spread by driving infected bats into neighboring colonies.
The findings, published in Proceedings of the National Academy of Sciences, suggest that geographic coordination of vampire bat control efforts in Latin America—taking into account the interconnectedness of seemingly isolated colonies—might reduce transmission to humans and domestic animals. The study also establishes that rabies is usually not lethal among vampire bats.
“In the paper last year, we demonstrated that bat colony size wasn’t a predictor of rabies prevalence, which indicated that culling hadn’t reduced transmission,” says Pejman Rohani, population ecologist and epidemiologist at the University of Michigan.
“In the current paper, we do a number of things. First, we fit models that encompass alternative assumptions regarding this system and we identify an important role of movement between colonies. We then use the best-fitting model to examine what happens under culling, especially if the cull is indiscriminate, rather than targeting infected bats specifically. Again, culling is shown to be ineffective, but now the model helps us understand why that is.”How bat rabies spreads
Developing effective control strategies for vampire bat-transmitted rabies virus in Latin America requires an understanding of the mechanisms that have allowed the highly virulent pathogen to persist despite control efforts. But understanding the persistence mechanisms has proved elusive, despite recognition of the virus and its health risks since the early 1900s.
To determine those persistence mechanisms, the researchers created four mathematical models of rabies transmission, each representing an alternative hypothesis for the biology of rabies infection.
Then they tested the models against data from a University of Georgia-led field study of rabies exposures in wild vampire bat colonies across Peru. That study tracked rabies exposures in individually marked Desmodus rotundus vampire bats from 17 colonies in four regions of Peru between 2007 and 2010 and yielded the most complete dataset on rabies exposure patterns ever collected for any bat species.
Thousands of computer simulations were run, and the most successful models demonstrated that a single, isolated vampire bat colony cannot maintain the rabies virus over time. Frequent movement of infectious bats between colonies is needed to keep the rabies virus at levels consistent with the field observations.The opposite effect
The critical role of immigration between bat colonies predicted by the analysis indicates that current culling practices, often reactive to outbreaks in livestock or haphazardly implemented, are unlikely to eliminate VBRV (vampire bat-transmitted rabies virus), the researchers write.
“While programs targeting specific colonies may limit local spillover from bats to humans or domestic animals, regional viral persistence will likely remain unaffected due to high connectivity between bat colonies,” Rohani says.
“Moreover, if culling increases movement due to freeing up space or disturbance-mediated dispersal, culling could, perversely, have the opposite of the intended effect on rabies transmission.”
Such a phenomenon has recently been observed in controlled badger culls in the United Kingdom, where disruption of badger social dynamics and subsequent dispersal led to increased tuberculosis transmission in cattle at neighboring sites.
The bat study’s other main finding is that the vast majority of rabies virus exposures among vampire bats—in which an infectious bat bites a susceptible individual—are nonlethal and actually immunize the bitten bat, thus helping to prevent colony extinction and sustain the virus.Unlimited food supply
The probability of a vampire bat developing a lethal infection upon exposure to rabies is around 10 percent, much lower than the 50-to-90 percent mortality rate seen in previous experimental “challenges studies” that involved inoculating vampire bats with rabies virus, according to the researchers.
In Latin America, coordinated efforts to eliminate human rabies transmitted by dogs began in 1983 and led to a roughly 90 percent reduction in human and canine rabies, according to the US Centers for Disease Control and Prevention. Since 2000, vampire bats have been the leading cause of human rabies there, especially in remote areas of the Amazon region in Peru, Ecuador, and Brazil.
Continued growth of the livestock industry likely exacerbates rabies outbreaks in the region by providing an almost unlimited food source for the blood-feeding bats, fueling population growth and range expansion. The combination of large vampire bat populations and frequent contact with livestock contributes to losses of about $30 million annually in Latin American livestock mortality.
Of more than 1,200 species of bats worldwide, only three are vampires, and all three live in Latin America, according to Bat Conservation International. Two of the species feed primarily on the blood of birds and one—the common vampire bat, D. rotundus—prefers mammals, especially livestock.Sounds of sleeping
Common vampire bats hunt only when it is fully dark and listen for the regular breathing sounds of sleeping mammals, which serve as their main food source. Once a target is located, the bat lands and approaches it on the ground. Vampire bats use heat sensors on their nose to locate warm spots where blood flows through vessels near the skin’s surface.
They use razor-sharp upper incisors to create small wounds. An enzyme in the saliva prevents clotting as the bat feeds, and a specialized groove in the tongue keeps blood flowing without the need for sucking or slurping.
“Movies notwithstanding, vampire bats do not suck blood. They lap it like kittens,” according Bat Conservation International.
Worldwide, more than 55,000 people die of rabies each year, according to the World Health Organization. More than 95 percent of the human deaths occur in Asia and Africa, and dogs are the source of infection in nearly all of those deaths.
Julie Blackwood, a former postdoctoral research associate in Rohani’s lab, is the paper’s senior author. Researchers from the University of Georgia contributed to the study, which was funded by the National Science Foundation, the University of Georgia, the Centers for Disease Control and Prevention, the National Geographic Society, the Department of Homeland Security, and the National Institutes of Health.
Source: University of Michigan
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In wetlands with a rich diversity of species, Pacific chorus frogs are far less likely to be infected with a virulent parasite than in species-poor wetlands.
The virulent parasite, Ribeiroia ondatrae, is a trematode that causes limb malformations in frogs and newts.
The finding sheds light on how biodiversity moderates the transmission of infectious diseases.Diversity paradox Related Articles On Futurity
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“The loss of species diversity has major implications for how harmful and deadly diseases are transmitted in nature,” says Jason Hoverman, an assistant professor of vertebrate ecology at Purdue University.
“While the risk of getting infected with this trematode is largely a factor of how many trematodes are present in the community, we found that disease transmission is also impacted by the number of host species and other parasite species in the system.”
The study addresses a paradox of disease ecology: In highly diverse communities, potential hosts are less likely to become infected with harmful pathogens, even though these communities contain more parasites overall.
In complex wetland systems, frogs may carry a greater number of parasites, but hosts and parasites work in tandem to prevent infections by the most virulent pathogens.
Reducing parasite diversity as well as host diversity greatly increases a frog’s risk of contracting a crippling parasite such as Ribeiroia ondatrae.
The implications of losing biodiversity go beyond wetlands, Hoverman says.
“What is amazing is that we’re finding these principles hold true for basically all disease systems, whether human, animal, or plant. Because human activities are linked to the loss of biodiversity, there are growing concerns that we could inadvertently influence the emergence of infectious diseases.”Diluted risk
About 43 percent of global amphibian populations are declining due to dwindling habitats and a rise in infectious diseases such as ranavirus and Ribeiroia ondatrae. To determine the relationships between disease transmission, amphibian diversity, and parasite diversity, Hoverman and researchers from the University of Colorado combined data from 345 wetlands, a laboratory experiment, and a controlled outdoor experiment.
“Most disease studies focus either on host diversity or parasite diversity,” Hoverman says. “But what we were able to do here was bring those two things together so we could look at the relative contribution of changes in host and parasite diversity on disease risk.”
In all three settings, higher host and parasite diversity resulted in fewer Ribeiroia ondatrae infections in Pacific chorus frogs. Increasing the number of amphibian species in a wetland reduced infections by Ribeiroia ondatrae and other parasites, a phenomenon known as the “dilution effect.”Parasite perks
Increasing the number of other parasite species further reduced trematode infections, highlighting the important role of parasites in regulating disease transmission, Hoverman says. The most diverse wetlands suppressed transmission of Ribeiroia ondatrae from ramshorn snails—the trematode’s intermediate host—to frogs by more than 50 percent.
“We always think about the negative connotations of parasites, but having more parasites is not equivalent to greater disease risk,” Hoverman says. “Most parasites are fairly benign. Disease risk is really defined as how many virulent parasites are in a community.”
The paper appears in the Proceedings of the National Academy of Sciences.
The David and Lucile Packard Foundation and the US National Science Foundation provided funding for the research.
Source: Purdue University
New theoretical calculations call into question what scientists thought they knew about how a neutron star heats itself up.
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The accepted theory is that nuclear reactions within the star’s thick outer layer contributed to surface heating.
“These cooling layers are pretty shallow beneath the surface,” says Hendrik Schatz, a professor of physics and astronomy at Michigan State University. “If heat from deeper within the star comes up, it hits this layer and never makes it to the surface.”
Schatz says this discovery produces more questions than answers.
“This completely changes the way we think about the question of the star’s hot surface,” he adds. “It’s a big puzzle now.”Football shape
On the sub-atomic level, the team found that the process is greatly affected by the shape of the reacting nuclei.
“Many nuclei are round, and that suppresses the neutrino cooling,” says Sanjib Gupta, co-author of the study published in Nature and faculty member at IIT Ropar in India. “In this case, the nuclei are predicted by theorists to be ‘deformed,’ more American football-shaped.”
This work was enabled by the Joint Institute for Nuclear Astrophysics, a National Science Foundation Physics Frontiers Center on Nuclear Astrophysics that promotes collaboration between astrophysicists and nuclear physicists.
Study co-authors include researchers from Los Alamos National Lab, the University of Notre Dame, the Universidade de Sao Paulo, Oak Ridge National Laboratory, the University of Tennessee, and the University of Washington.
Source: Michigan State University
Flower color has evolved to attract bees as pollinators in subtropical and steep mountain environments, a new study shows.
Previous studies have shown that flower color evolved to attract bees as pollinators in temperate environments, but the story for either subtropical or steep mountainous environments had been unknown, according to associate professor Adrian Dyer of Monash and RMIT Universities.Related Articles On Futurity
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The study took place in the understudied Nepalese steep mountainous terrain and other subtropical environments. Published in the Journal of Ecology, it has implications for understanding the effects of climate change on plant pollination.
“Mountainous environments provide an ideal natural experiment to understand the potential effects of changing climatic conditions on plant-pollinator interactions, since many pollinators show preferences for localized conditions, and major pollinators like honeybees do not tend to forage at high altitudes,” says Dyer.
Mani Shrestha from Monash University and colleague Prakash Bhattrai from the Tribhuvan University, Kathmandu, collected spectral data from more than 100 flowering plants in Nepal over a range of altitudes, from approximately 3,000 to over 13,000 feet.
Using computer models to examine flower colors as bees would see them, the team addressed how pollinator vision had shaped flower evolution. Then, with associate professor Martin Burd of the School of Biological Sciences, they did phylogenetic analyses to identify how altitude zones affected results.Flower color surprise
Shrestha says flowers from both subtropical (roughly 3,000-6,500 feet) and alpine (roughly 10,000 to 13,500 feet) regions showed evidence of having evolved color spectral signatures to enhance discrimination by bee pollinators.
“The finding was a surprise as flies are thought to be the main pollinator in many mountain regions, but it appears that in the Himalayas several bee species are also active at high altitude, and these insects have been such effective pollinators that they have led to the evolution of distinctive bee-friendly colors,” Shrestha says.
The research could shed light on how flower colors may continue to evolve in particular environments, depending upon the availability of the most effective pollinators.
While “bee colors” were prevalent at all elevations, flower colors in high altitude zones were more diverse and had more often undergone larger steps of evolutionary change than those at lower elevation, says Burd.
“Studying these patterns helps scientists understand how plant communities are assembled, and are potentially able to deal with changing conditions.”
A grant from the Australian Research Council assisted the work.
Source: Monash University
Young girls who have been sexually abused reach puberty earlier than their peers, which can increase their risk of having emotional problems, new research shows.
“Early maturing girls are already more vulnerable to mood problems than other kids, but this risk seems to be magnified for girls with histories of sexual abuse,” says Jane Mendle, assistant professor of human development at Cornell University.Related Articles On Futurity
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“Girls who reach puberty ahead of peers are substantially more likely to be targets of peer sexual harassment and receive a high number of unsolicited comments on their bodies.”
About one in five girls in the United States have a history of sexual abuse—and these added challenges and pressures may become a tipping point for emotional difficulties such as depression and anxiety, Mendle says.
For the study published online in the Journal of Research on Adolescence, researchers studied 100 girls in foster care, all of whom had experienced maltreatment early in childhood.They looked at the type of maltreatment (physical abuse, sexual abuse, or neglect), emotional symptoms, and level of physical maturity reported at two points, two years apart.
The team found no direct effects of abuse on the girls’ emotional symptoms. Rather, they found that the number of sexual abuse instances, but not physical abuse or neglect instances, was linked to earlier pubertal timing.Puberty experiences
It was these earlier developing girls that had more symptoms of depression, anxiety, and social withdrawal. The study showed that girls’ emotional problems were directly related to their experiences at puberty—not to what happened to them early in life.
“In addition to individual interventions (to help early maturing girls), another target might be our collective social response to early puberty,” Mendle says.
“Peers, caregivers, teachers and other adults have a tendency to react to children based on their observable—rather than chronological—age. Those reactions can be very powerful for how girls respond and interpret the challenges of growing up.”
Researchers from the University of Oregon and the University of California, Riverside contributed to the study that was supported in part by the National Institute on Drug Abuse.
Source: Cornell University
Captive breeding programs for Asian elephants need better methods for collecting semen, according to researchers.
Crushed by habitat loss and poaching, Asian elephants are at risk, and their future rests heavily on captive breeding programs. Highly varying quality in Asian elephant semen samples has made captive breeding programs difficult.
The study, published in PLOS ONE, suggests that sperm quality itself is not the problem, but rather that collection techniques do not reliably stimulate all the organs needed to produce seminal plasma, the surrounding fluid that supports sperm function.Related Articles On Futurity
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“Captive breeding in elephants is extremely difficult,” says study co-author Alex Travis, director of Cornell University’s Center for Wildlife Conservation, and faculty director for the environment in Cornell’s Atkinson Center for a Sustainable Future.
“Moving elephants isn’t easy. Few facilities are equipped to handle powerful bulls [males]. Ideally we’d move genes around through use of semen samples like in cattle and dog breeding.”Missing component
Even samples taken from the same male elephants often vary greatly in motility—sperms’ ability to move. To understand why, Smithsonian scientists Wendy Kiso and Budhan Pukazhenthi collected samples from 21 male elephants, each of which produced both bad (low motility) and good (high motility) samples.
They partnered with Travis and graduate student Jennifer Nagashima to compare the good and bad samples from each elephant using advanced techniques in Travis’s lab. The problem in bad samples turned out not to be the sperm—they looked the same and were present in the same numbers as in good samples.
So the team removed the sperm to examine the seminal plasma, the nutritive brew that helps fuel and protect sperm in the female reproductive tract. Good samples had higher volumes of plasma. They also found that a particular protein showed up in almost all of the good samples and almost none of the bad ones.
Using mass spectrometry and immunoblotting techniques, they identified it as lactotransferrin. Lactotransferrin is associated with accessory sex glands, which make seminal plasma.It’s not the elephants
Elephants’ accessory sex glands are buried deep inside the abdomen. Lactotransferrin’s absence in bad samples taken from the same animals that also produced good samples with lactotransferrin suggests that these organs are not reliably stimulated, leading to discrepancies in semen sample quality.
“This is an exciting discovery because it tells us the problem isn’t the elephants; it’s the sperm collection methods,” says Travis. “This suggests we need to develop methods that can reliably stimulate the accessory sex glands in order to produce high-quality samples.
“It also suggests that we might one day develop media that could rescue the function of the sperm even if the collection technique didn’t adequately stimulate normal seminal plasma production.”
These findings lay a foundation for understanding seminal plasma’s importance in Asian elephant sperm motility and poise conservation science for improved semen collection and storage techniques crucial to maintaining genetic diversity in this endangered species.
Feld Entertainment Inc., International Elephant Foundation, Friends of the National Zoo, and the Baker Institute for Animal Health partially funded the research.
Source: Cornell University
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People who live with chronic pain may need to build a new relationship with their body, rather than try to maintain their regular lifestyle.
Researchers say patients with chronic musculoskeletal pain often struggle with a sense of self and may find it difficult to justify their condition to themselves and to those around them.Related Articles On Futurity
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For a new study published in the journal Health Services and Delivery Research, scientists compiled the findings of 77 studies of chronic musculoskeletal pain to understand the experiences of patients who suffer from the condition.
Key findings include:
- Patients may struggle with the fundamental relationship with their body and have a sense that it is no longer “the real me.”
- Patients may experience a loss of certainty for the future, and be constantly aware of the restrictions of their body.
- Patients feel lost in the health care system and believe there is no answer to their pain.
- Patients find it impossible to “prove” their pain and worry “if I appear ‘too sick’ or ‘not sick enough’ then no one will believe me.”
“Being able to collate this vast amount of information from patients paints a worrying picture about the experiences they have with chronic non-malignant pain,” says Kate Seers, professor of health research at the University of Warwick Medical School.Legitimize pain
“Our goal has to be to use this information to improve our understanding of their condition and, consequently, the quality of care we can provide.
“Having patients feel that they have to legitimize their pain, and the sense that doctors might not believe them, is something that should really concern us as health care professionals.”
To move forward with their lives, researchers say people with chronic pain need to build a new relationship with their body and redefine what is “normal,” rather than try to maintain the same lifestyle. By developing an understanding of what their body is capable of, patients can become confident to make choices that will help them live with the pain.
“This paper shows there can be value in discussing the condition with other people who are going through the same experience and knowing that you are not alone,” says Francine Toye, of Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Trust.
“Of course you can learn about your condition from various sources, but sharing your experience seems to really help people to move forward.”
Source: University of Warwick