Τετάρτη, 30 Απριλίου 2014

ScienceDaily: Latest Science News

ScienceDaily: Latest Science News

Consuming high-protein breakfasts helps women maintain glucose control, study finds

Posted: 29 Apr 2014 01:21 PM PDT

Previous research has shown that extreme increases in glucose and insulin in the blood can lead to poor glucose control and increase an individual's risk of developing diabetes over time. Now, a researcher has found that when women consumed high-protein breakfasts, they maintained better glucose and insulin control than they did with lower-protein or no-protein meals.

Prematurity linked to altered lung function during exercise, high blood pressure in adults

Posted: 29 Apr 2014 01:16 PM PDT

Some preterm babies have lungs that develop abnormally. While long-term health effects of prematurity are still unclear, researchers have found that adults who were born early may have problems handling the pulmonary demands of exercise. "Healthy young humans have lungs designed to easily handle the increased blood flow from the heart during exercise. However, adults born extremely to very preterm have abnormally developed lungs, which may result in lungs that are unable to handle the demands of exercise," they conclude.

Heat regulation dysfunction may stop MS patients from exercising

Posted: 29 Apr 2014 01:16 PM PDT

Exercise-induced body temperature increases can make symptoms worse for some patients with multiple sclerosis. Researchers have explored the underlying causes of the temperature regulation problems so MS patients can better reap the benefits of exercise. In the study, researchers found that sweating took longer to start and sweat rate was lower during exercise-induced body temperature increases in MS patients compared to healthy control subjects.

Don't like the food? Try paying more

Posted: 29 Apr 2014 01:16 PM PDT

Customers paying more at a restaurant buffet perceive the food as tastier than the same food offered at a lower price, suggesting taste perception can be manipulated by price alone. Researchers in nutrition, economics and consumer behavior often assume that taste is a given -- a person naturally either likes or dislikes a food. But a new study suggests taste perception, as well as feelings of overeating and guilt, can be manipulated by price alone.

Information technology can simplify weight-loss efforts; social support still important for success

Posted: 29 Apr 2014 12:37 PM PDT

According to the Centers for Disease Control and Prevention, 69 percent of adults in the United States are currently overweight or obese, which puts these individuals at increased risk for chronic health problems. Although weight loss decreases this risk, statistics show that dieters often fail multiple times before meeting their goals. Now, researchers have found that information technology, such as smartphone applications, can help dieters integrate healthy behavior changes into their daily lives.

Saving crops, people with inexpensive bug sensors

Posted: 29 Apr 2014 12:37 PM PDT

A method that can classify different species of insects with up to 99 percent accuracy has been created by researchers, a development that could help farmers protect their crops from insect damage and limit the spread of insect-borne diseases, such as malaria and Dengue fever. For hundreds of years humans have attempted to kill unwanted insects. While some blanket methods have been successful, they can be costly and create environmental problems. The sensor developed by these researchers aims to change that by counting and classifying the insects so that the substance used to eradicate the harmful insects can be applied on a precision targeted level.

Declines in large wildlife lead to increases in disease risk

Posted: 29 Apr 2014 11:22 AM PDT

In the Middle Ages, fleas carried by rats were responsible for spreading the Black Plague. Today in East Africa, they remain important vectors of plague and many other diseases, including Bartonellosis, a potentially dangerous human pathogen. The researchers concluded that the "spike in disease risk results from explosions in the number of rodents that benefit from the removal of the larger animals."

Chronic stress heightens vulnerability to diet-related metabolic risk

Posted: 29 Apr 2014 11:21 AM PDT

Highly stressed people who eat a lot of high-fat, high-sugar food are more prone to health risks than low-stress people who eat the same amount of unhealthy food, new research finds for the first time. Metabolic syndrome is a cluster of abnormalities -- increased blood pressure, a high blood sugar level, excess body fat around the waist and abnormal cholesterol levels -- that occur together, increasing a person's risk of heart disease, stroke and diabetes.

Prehistoric caribou hunting structure discovered beneath Lake Huron

Posted: 29 Apr 2014 10:38 AM PDT

Underwater archaeologists have discovered evidence of prehistoric caribou hunts that provide unprecedented insight into the social and seasonal organization of early peoples in the Great Lakes region. The main feature, called Drop 45 Drive Lane, is the most complex hunting structure found to date beneath the Great Lakes.

'Feel good' factor higher when you own, not just use, luxury items

Posted: 29 Apr 2014 10:38 AM PDT

It means more to people to own a luxury product or brand than to have the privilege of simply using one. Just using an affordable luxury item you don't own can, in fact, dampen the feel good factor that normally surrounds such products, suggests new research.

Immunogenic mutations in tumor genomes correlate with increased patient survival

Posted: 29 Apr 2014 10:38 AM PDT

Developing immunotherapies for cancer is challenging because of significant variability among tumors and diversity in human immune types. In a new study, researchers examined the largest collection of tumor samples to date to predict patient-specific tumor mutations that may activate the patient's immune system, paving the way for more successful, personalized cancer immunotherapy.

Graphene very mobile in lakes: Risks of negative environmental impacts if released

Posted: 29 Apr 2014 09:58 AM PDT

In a first-of-its-kind study of how a material some think could transform the electronics industry moves in water, researchers found that graphene oxide nanoparticles are very mobile in lakes or streams and therefore may well cause negative environmental impacts if released.

Brain tumor cells penetrated by tiny, degradable particles carrying genetic instructions

Posted: 29 Apr 2014 09:58 AM PDT

Tiny, biodegradable 'nanoparticles' able to carry DNA to brain cancer cells in mice have been developed by engineers and neurosurgeons working together. The team says the results of their proof of principle experiment suggest that such particles loaded with 'death genes' might one day be given to brain cancer patients during neurosurgery to selectively kill off any remaining tumor cells without damaging normal brain tissue.

Medicare patients with dementia 20 percent more likely to be readmitted

Posted: 29 Apr 2014 09:58 AM PDT

A review of more than 25,000 admissions of Medicare beneficiaries to Rhode Island hospitals has found that patients with a documented diagnosis of dementia are nearly 20 percent more likely to be readmitted within 30 days than those without dementia. "Because dementia often goes undiagnosed, or is not documented in a patient's medical record, we believe that the current findings may underestimate readmission rates and risks in this population," the lead author noted.

People rely on what they hear themselves say to know what they're saying

Posted: 29 Apr 2014 09:57 AM PDT

You know what you're going to say before you say it, right? Not necessarily, research suggests. A new study shows that auditory feedback plays an important role in helping us determine what we're saying as we speak. Theories about how we produce speech often assume that we start with a clear, preverbal idea of what to say that goes through different levels of encoding to finally become an utterance. But the findings from this study support an alternative model.

Anti-bullying policy must focus on all of society

Posted: 29 Apr 2014 09:57 AM PDT

Policy to reduce bullying in the schoolyard needs to span all levels of society, say researchers, who warn that socioeconomic status is not a reliable indicator of whether a child is likely to become a bully. Up to one third of children are involved in bullying, and a growing body of evidence has shown that bullying is a significant public health concern, which can cause long lasting health and social problems.

Mother's diet affects the 'silencing' of her child's genes

Posted: 29 Apr 2014 09:57 AM PDT

A unique 'experiment of nature' that took place in The Gambia has now revealed that a mother's diet before she conceives has a permanent effect on her offspring's genetics. This is the first time the effect has been seen in humans, and is regarded as a major contribution to the field of 'epigenetics.'

Molecular secrets behind resveratrol's health benefits revealed

Posted: 29 Apr 2014 09:55 AM PDT

Resveratrol has been much in the news as the component of grapes and red wine associated with reducing "bad cholesterol," heart disease and some types of cancer. Also found in blueberries, cranberries, mulberries, peanuts and pistachios, resveratrol is associated with beneficial health effects in aging, inflammation and metabolism.

How laws need to change to catch up with algorithmic stock trading

Posted: 29 Apr 2014 09:55 AM PDT

High speed algorithms have so revolutionized the design and functioning of our stock markets that they are fast tearing up the rule book in how these markets are regulated, according to a researcher.

Label-free, sequence-specific, inexpensive fluorescent DNA sensors

Posted: 29 Apr 2014 09:55 AM PDT

Using principles of energy transfer more commonly applied to designing solar cells, scientists have developed a new highly sensitive way to detect specific sequences of DNA, the genetic material unique to every living thing. The method is considerably less costly than other DNA assays and has widespread potential for applications in forensics, medical diagnostics, and the detection of bioterror agents.

Fridges cooled by magnetism? Newly identified 'universal' property of metamagnets may lead to everyday uses

Posted: 29 Apr 2014 09:55 AM PDT

A new physics discovery may lead to more efficient refrigerators, heat pumps and airport scanners, among many possible uses –- perhaps within a decade.The refrigerator of 2024 may be cooled not by chemical refrigerants, but by magnetism, thanks to the work of a team of physicists and materials scientists.

Proving uncertainty: New insight into old problem

Posted: 29 Apr 2014 09:54 AM PDT

Nearly 90 years after Werner Heisenberg pioneered his uncertainty principle, a group of researchers from three countries has provided substantial new insight into this fundamental tenet of quantum physics with the first rigorous formulation supporting the uncertainty principle as Heisenberg envisioned it.

Plasma flows in laboratory used to understand how beam-like jets may form in space

Posted: 29 Apr 2014 07:51 AM PDT

Streaming jets of high-speed matter produce some of the stunning objects seen in space. Astronomers have seen them shooting out of young stars just being formed, X-ray binary stars and supermassive black holes at the centers of large galaxies. Theoretical explanations for what causes those beam-like jets have been around for years, but now an experiment using extremely high-powered lasers offers experimental verification of one proposed mechanism for creating them.

Women's employment, caregiving workloads, effort, health profiled by researchers

Posted: 29 Apr 2014 07:51 AM PDT

A profile of women with the dual responsibilities of full-time paid work and unpaid care for an elderly family member has been developed by researchers. The study is similar to how industry measures the impact of workload (including the time and difficulty of the tasks) and effort (the perceived energy it takes to do the work), researchers said. The results richly described the experiences of 46 women caregivers who work full-time and participated in the researchers' larger mixed-methods study in 2012.

Take a trip down Memory Lane to the gym: Using memories to motivate

Posted: 29 Apr 2014 07:50 AM PDT

We all know that thinking about exercise isn't the same as doing it. But researchers have confirmed what may be the next best thing: just thinking about a past exercise experience can motivate us to actually do it.

Depression detectable in the blood: Platelet serotonin transporter function

Posted: 29 Apr 2014 07:50 AM PDT

The possibility of using a blood test to detect depression has been demonstrated by researchers. While blood tests for mental illnesses have until recently been regarded as impossible, a recent study clearly indicates that, in principle, depression can in fact be diagnosed in this way and this could become reality in the not too distant future.

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

Posted: 29 Apr 2014 07:49 AM PDT

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. 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.

Girls make higher grades than boys in all school subjects, analysis finds

Posted: 29 Apr 2014 07:49 AM PDT

Despite the stereotype that boys do better in math and science, girls have made higher grades than boys throughout their school years for nearly a century, according to a new analysis. "School marks reflect learning in the larger social context of the classroom and require effort and persistence over long periods of time, whereas standardized tests assess basic or specialized academic abilities and aptitudes at one point in time without social influences," said lead study author.

More coral babies staying at home on future reefs

Posted: 29 Apr 2014 06:27 AM PDT

Increasing ocean temperatures due to climate change will soon see reefs retaining and nurturing more of their own coral larvae, leaving large reef systems less interconnected and potentially more vulnerable. "We found that at higher temperatures more coral larvae will tend to stay on their birth reef," says the lead author of the study.

Risk-assessment approach recommended for biomarker-driven cancer clinical trials

Posted: 29 Apr 2014 06:26 AM PDT

A practical, risk-management approach has been outlined by experts for effective integration of biomarkers into cancer clinical trials. This work provides the international community with a set of common principles by which biomarkers can be integrated into clinical trials, exchange of data can be facilitated, quality promoted, and research accelerated while simultaneously respecting local approaches and legislation.

Coral reefs provide potent new anti-HIV proteins

Posted: 29 Apr 2014 06:26 AM PDT

A new class of proteins capable of blocking the HIV virus from penetrating T-cells has been discovered. The proteins, found in a coral from Australia's northern coast, could be well-suited for use in gels or sexual lubricants to provide a potent barrier against HIV infection, potentially filling a pressing need for a female-applied anti-HIV microbicide that doesn't rely on a man's willingness to use a condom.

Talking to kids about money: Study highlights importance of parents discussing financial matters with children

Posted: 29 Apr 2014 06:25 AM PDT

A new study finds that children pay close attention to issues related to money, and that parents should make an effort to talk with their children to ensure that kids don't develop misconceptions about finance. The children reported that some subjects were largely "off-limits," including family finances, parental income, investments and debt.

Microfluidic technology reveals potential biomarker for early pancreatic cancer

Posted: 29 Apr 2014 06:25 AM PDT

The detection of pancreas cells in the blood may be an early sign of cancer, new research demonstrates. The findings suggest that circulating pancreas cells (CPCs) seed the bloodstream before tumors can be detected using current clinical tests such as CT and MRI scans, and that the detection of pancreas cells in the blood may be an early sign of cancer.

Submarine: 'Virtual periscope' sees above-surface/airborne objects from underwater view

Posted: 29 Apr 2014 06:25 AM PDT

Researchers have developed an underwater imaging system that allows submariners to view objects above the water's surface - without a periscope. The unique technology gets around the inevitable distortion caused by the water-surface waves when using a submerged camera because of the sharp refractive differences between water and air, random waves at the interface present distortions that are worse than the distortion atmospheric turbulence creates for astronomers peering into space.

Snobby staff can boost luxury retail sales

Posted: 29 Apr 2014 05:56 AM PDT

When it comes to luxury brands, the ruder the sales staff the better the sales, according to new research. The study reveals that consumers who get the brush-off at a high-end retailer can become more willing to purchase and wear pricey togs. "It appears that snobbiness might actually be a qualification worth considering for luxury brands like Louis Vuitton or Gucci," says one marketing professor. "Our research indicates they can end up having a similar effect to an 'in-group' in high school that others aspire to join."

When harm done can never be balanced: Vicarious revenge and the death of Osama bin Laden

Posted: 29 Apr 2014 05:56 AM PDT

Friday will mark the third anniversary of Osama bin Laden's assassination, a day when President Barack Obama famously stated 'Justice has been done.' But has it? A new study has questioned whether this instance of vicarious revenge led to feelings of satisfaction and reestablished justice within the American public, including whether bin Laden's assassination ignited craving for more revenge.

Overlap in genes altered in schizophrenia, autism, intellectual disability

Posted: 29 Apr 2014 05:56 AM PDT

New evidence supporting the theory that in at least some cases of schizophrenia, autism and intellectual disability, malfunctions in some of the same genes are contributing to pathology has been released. Schizophrenia is thought to be caused in many instances by gene mutations passed from parents to children, the effects of which may be enhanced by adverse environmental factors. In contrast, de novo mutations, or DNMs, are gene defects in offspring that neither parent possesses. Researchers used these differences as their focus in the new study.

Low cholesterol in immune cells tied to slow progression of HIV

Posted: 29 Apr 2014 05:55 AM PDT

People infected with HIV whose immune cells have low cholesterol levels experience much slower disease progression, even without medication, according research that could lead to new strategies to control infection. The researchers found that low cholesterol in certain cells, which is likely an inherited trait, affects the ability of the body to transmit the virus to other cells.

Diabetes duration, severity associated with brain atrophy

Posted: 29 Apr 2014 05:55 AM PDT

Type 2 diabetes may be associated with brain degeneration, according to a new multi-center study. The study also found that, contrary to common clinical belief, diabetes may not be directly associated with small vessel ischemic disease, where the brain does not receive enough oxygenated blood.

E-games for kids: How to avoid the dangers

Posted: 29 Apr 2014 05:53 AM PDT

Children's access to e-games has increased exponentially in recent years. Diversification of platform; tablets, handheld games consoles, and smartphones give kids opportunity for exposure almost all the time in any setting.  In developed countries kids spend a shocking 4-8 hours per day using screen based electronic media.  What are the risks attached to such high usage?  Are there any benefits? What should parents, health and education professionals and the industry be doing about it? 

'Tell-tail' MRI image diagnosis for Parkinson's: Healthy state of brain cells may be an accurate test

Posted: 29 Apr 2014 05:53 AM PDT

An image similar in shape to a Swallow's tail has been identified as a new and accurate test for Parkinson's disease. The image, which depicts the healthy state of a group of cells in the sub-region of the human brain, was singled out using 3T MRI scanning technology – standard equipment in clinical settings today. 

New fluorescent hybrid material changes color according to direction of light

Posted: 29 Apr 2014 05:53 AM PDT

Scientists have developed a highly fluorescent hybrid material that changes color depending on the polarization of the light that it is illuminated by. The aim with respect to hybrid materials with one organic component and another inorganic one is to combine the best attributes of each one into a single system.

How the koala retrovirus genome evolved

Posted: 29 Apr 2014 05:53 AM PDT

Retroviruses invaded the genome of koalas with strongly pathological effects: the viruses weaken the immune defense and threaten the viability of the already reduced koala population. Scientists have now applied the technique of hybridization capture to analyze the entire genome of koala retroviruses and used museum samples to monitor its variation across 130 years.

Race, risk and behaviors: Type 2 diabetes update

Posted: 29 Apr 2014 05:53 AM PDT

The behavioral issues associated with patients' self-management of type 2 diabetes is the special focus of a recent journal release. "Diabetes, perhaps more so than any other chronic disease, requires people to significantly modify their behaviors -— sometimes in ways that are contrary to their cultural norms and backgrounds -— even when they don't 'feel' sick or experience symptoms of the disease," said one expert. Type 2 diabetes is a metabolic disorder affecting about 24 million people in the United States.

Cheap, environmentally-friendly method for making transparent conductive films for laptops, smartphones, solar cells

Posted: 29 Apr 2014 05:53 AM PDT

Transparent conductive films are now an integral part of our everyday lives. Whether in smartphones, tablets, laptops, flat screens or (on a larger scale) in solar cells. Yet they are expensive and complex to manufacture. Now, researchers have succeeded in developing a method of producing such TCO films, as they are known, that is not only cheaper, but also simpler and more environmentally friendly.

I don’t deserve to be this happy: Dampening of positive feelings found to predict postpartum depressive symptoms

Posted: 29 Apr 2014 05:52 AM PDT

For the first time, research shows that the dampening or suppression of positive emotions plays an important role in the development of postpartum depression. This has implications for the treatment of depressed mothers. The researchers are currently working to develop a treatment method focused specifically on counteracting dampening. Existing methods, such as mindfulness, may also have a positive effect on dampening they say.

Stress research in therapy dogs reveals animals' needs

Posted: 29 Apr 2014 05:52 AM PDT

Animals exert positive effects on humans. This fact has been proven scientifically and is used increasingly often for specific therapeutic purposes. Scientists have now investigated how therapy dogs feel in a therapy setting and how one can create a largely stress-free situation for the animals. The current study shows that, during group therapy, dogs are not subjected to greater stress than they are during their leisure time. Prerequisites for this purpose are the voluntary involvement and self-determinism of the dogs.

New goals set for global health research, training

Posted: 29 Apr 2014 05:51 AM PDT

Global health research and training efforts should focus on combating the growing epidemic of noncommunicable diseases, better incorporating information technology into research and training, and more effectively converting scientific discoveries into practice in low-resource settings, according a new strategic plan for a global health research group.

Urban river pollutants suppress wild bird development

Posted: 28 Apr 2014 06:04 PM PDT

Hormone disrupting pollutants are affecting the health and development of wild birds nesting along the urban rivers of South Wales, new research shows. Findings reveal that chicks of the Eurasian Dipper -- a river bird that feeds exclusively on insects and fish in upland streams -- are underweight compared to their rural counterparts. Also of concern is that birds nesting in urban rivers have altered hormone levels, and are hatching fewer female chicks than those nesting along rural rivers, which could have negative implications for the population's breeding and survival.

Bacteria on the skin: Our invisible companions influence how quickly wounds heal

Posted: 28 Apr 2014 06:02 PM PDT

A new study suggests microbes living on our skin influence how quickly wounds heal. The findings could lead to new treatments for chronic wounds, which affect 1 in 20 elderly people. We spend our lives covered head-to-toe in a thin veneer of bacteria. But despite a growing appreciation for the valuable roles our resident microbes play in the digestive tract, little is known about the bacteria that reside in and on our skin.

Epileptic or non-epileptic seizures? Misdiagnosis common

Posted: 28 Apr 2014 02:15 PM PDT

A research team set out to estimate the probability of epilepsy versus non-epileptic seizures based on the historical factors reported by the patient to their neurologist. Distinguishing between epileptic and non-epileptic seizures is a challenge, according to experts. On average, the time from the first seizure to the diagnosis of non-epileptic seizures is seven years. In the meantime, a majority of those patients are misdiagnosed with epilepsy and treated inappropriately with anti-epileptic medications.

Simply being called 'fat' makes young girls more likely to become obese: Trying to be thin is like trying to be tall

Posted: 28 Apr 2014 01:41 PM PDT

Girls who are told by a parent, sibling, friend, classmate or teacher that they are too fat at age 10 are more likely to be obese at age 19, a new study by psychologists shows.

Pancreatic tumor-induced gene may prove beneficial as a drug marker

Posted: 28 Apr 2014 01:36 PM PDT

A new mouse model helps scientists better understand the progression of pancreatic cancer and may provide new avenues for the development of therapies, researchers report. Cancer of the pancreas, with a 5% survival rate within five years of diagnosis, is the fourth leading cause of cancer related deaths. The main reason behind such high morbidity is poor early detection capabilities as well as inability of currently employed drugs to alleviate cancer progression.

Road to fountain of youth paved with fast food ... and sneakers? Exercise may prevent or delay fundamental process of aging

Posted: 28 Apr 2014 01:36 PM PDT

Unhealthy lifestyle habits can accelerate the process of senescence (cell death) and the release of damaging substances from dying cells. Researchers for the first time demonstrate that exercise can prevent or delay this fundamental process of aging, and that lifestyle choices do play a major role in cell aging and that exercise may help protect against aging by interfering with cell senescence.

Ready, set, hot!: Does warm weather play a role in football concussions?

Posted: 28 Apr 2014 01:36 PM PDT

Heat and dehydration can cause a "perfect storm" of risk factors for concussion among competitive football players. Researchers looked at the effects of extreme temperature on concussion rates during NCAA football games. A loss of just two percent of the body's water volume to dehydration -- a feat easily achieved during prolonged exercise in hot weather -- can lead to a significant reduction in the amount of cerebrospinal (CSF) fluid that a person has.

Naked mole rats and the secret to longevity

Posted: 28 Apr 2014 01:36 PM PDT

With lifespans of up to 31 years, naked mole rats live decades longer than would be expected based on their size. By comparison, mice live at most four years. A new study links their remarkable lifespans to high levels of a quality-control protein, offering new insights on age-related diseases like Alzheimer's and Parkinson's.

Smart home programming: Easy as 'if this, then that'

Posted: 28 Apr 2014 12:58 PM PDT

The idea of a smart home sounds promising enough -- who doesn't want a house full of automated gadgets, from light switches to appliances to heating systems, that know exactly when to turn on, turn off, heat up or power down? -- but how will users make sure all those automated devices are doing what they're supposed to do? Researchers have shown that a programming model quite well for smart home applications.

Cyberspace scholarship nets higher grades, better thinking for class Facebook group

Posted: 28 Apr 2014 12:58 PM PDT

University students who used a Facebook group as part of a large sociology class did better on course assignments and felt a stronger sense of belonging, researchers have found. The study has implications for the challenge of teaching large classes, a growing concern for higher education. "Although some teachers may worry that social media distracts students from legitimate learning, we found that our Facebook group helped transform students from anonymous spectators into a community of active learners -- and this has important consequences for student performance," said a co-author of the study.

Precise brain mapping can improve response to deep brain stimulation in depression

Posted: 28 Apr 2014 12:58 PM PDT

Precisely defining white matter connections in the brain can help physicians choose optimal target sites for stimulation and significantly improve outcomes in deep brain stimulation for depression, a new study shows. Previous experimental studies have shown that deep brain stimulation (DBS) within the subcallosal cingulate (SCC) white matter of the brain is an effective treatment for many patients with treatment-resistant depression.

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