Today at Disrupt NY 2013, Flipboard CEO Mike McCue said that publishers are facing a huge reduction in ad revenues. Publishers have seen revenues go from dollars in print, to dimes on the web, to pennies on mobile. According to McCue, a lot of the reason for that is the way that content is packaged and ads are displayed.Source: http://feedproxy.google.com/~r/Techcrunch/~3/wCEHXl4zSOo/
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Public release date: 30-Apr-2013
Share ] Contact: Rani Gran
rani.c.gran@nasa.gov
301-286-2483
NASA/Goddard Space Flight Center
Ground data now being collected in northeastern Iowa by the Iowa Flood Studies experiment will evaluate how well NASA's Global Precipitation Measurement (GPM) mission satellite rainfall data can be used for flood forecasting.
GPM is an international satellite mission that will set a new standard for precipitation measurements from space, providing worldwide estimates of precipitation approximately every three hours. The GPM Core Observatory, provided by NASA and mission partner the Japan Aerospace Exploration Agency, will launch in early 2014. Scientists are already at work, however, developing the methods for turning satellite observations into meaningful data by measuring rainfall with existing satellites and rain gauges in the field, and then using that data for societal applications, such as flood forecasting and monitoring of water resources.
"We're trying to figure out how well our satellites estimate rainfall," said Walt Petersen, GPM ground validation scientist at NASA's Wallops Flight Facility in Virginia. "This study is unique in that it takes space-borne observations, it takes ground-based observations, and it brings those things into a modeling framework that should further our ability to predict flooding."
With rainfall estimates in hand, the science teams input them into flood prediction computer models and then evaluate how the rain estimates and their uncertainties affect the outcome of the flood forecast, said Petersen. Rainfall estimates of water content and intensity are vital inputs for forecasters who need that information to determine whether or not streams and rivers will flood and impact people living in the floodplain.
The field campaign, which is taking place from May 1 to June 15, is a partnership between NASA and the Iowa Flood Center at the University of Iowa, Iowa City. The Iowa Flood Center was established after the unprecedented flooding, particularly of Cedar Rapids, in 2008, said Witold Krajewski, the Center's director. Since then, the Center has improved field monitoring of stream and river height and developed a 'library' of flood inundation maps of where flooding may occur for some of Iowa's most vulnerable communities.
Many variables go into flood prediction, said Krajewski, including soil type and moisture, stream and river geography, and land use. Some variables are difficult to measure, such as how water flows underground after it soaks into the ground. Rainfall, while challenging, is one of the easier variables to measure because we can see it, he said.
The field campaign, called the Iowa Flood Studies experiment, or IFloodS, will collect data from a vast network of ground instruments as well as instruments on satellites passing overhead. The ground instruments include rain gauges; instruments to measure soil moisture and temperature; disdrometers, which measure raindrop numbers, sizes and shapes as they reach the surface; and advanced precipitation radars, which measure the characteristics of rain as is falls.
The advanced NASA Polarimetric (NPOL) precipitation radar being deployed just south of Waterloo, Iowa, will look at rainfall above a line of ground instruments stretching toward Iowa City. The NPOL radar scans a volume of the atmosphere as it transmits pulses oriented in two directions, horizontal and vertical, returning three-dimensional images that provide information for distinguishing the size, shape and distribution of raindrops within rainclouds. This view will help scientists understand the physics of rainfall, essentially where ice, rain and sleet occur in clouds, how precipitation particles form, grow and interact, and how the distribution of raindrops changes as a function of height, said Petersen.
"The physics in the air column, all the way to the top of the cloud, affect how that rain forms and falls and how much rain you get at the surface," he said. Better understanding of the physics will improve rainfall estimates from space.
A second NASA ground radar, called the Dual-Frequency, Dual-Polarimetric Doppler Radar (D3R), will collect data at similar frequencies to the Dual-frequency Precipitation Radar that will fly on the upcoming GPM Core Observatory. The orbiting satellites that will collect data as they pass over Iowa each carry an instrument called a microwave radiometer, the same type of instrument as the Core's second instrument, the GPM Microwave Imager.
The satellite data used during the campaign will be from NASA's Tropical Rainfall Measuring Mission (TRMM), CloudSat, and Suomi National Polar Partnership (NPP) satellites; NOAA's 16, 18, and 19 weather satellites; the Defense Satellite Monitoring Program (DSMP) satellites; JAXA's Global Change Observation Mission-Water (GCOM-W1) satellite; and the European Union's METOP A and B weather satellites. In addition, the geosynchronous GOES satellite products will be analyzed.
"Here in Iowa, we have basins of varied sizes that are well instrumented compared to some other parts of the country," said Krajewski. That's one reason that NASA chose Iowa for its field campaign, according to Petersen. Krajewski added, however, that with the additional instruments from NASA, "collectively we will be gathering data that will be without precedent."
The GPM and IFloodS science teams will first use the ground radar and gauge data to develop a reference for how much rain is actually falling out of the sky, said Petersen. They can then compare the ground reference to those of the satellite estimates of rainfall. Secondly, both sets of data are fed into flood forecasting models for the Cedar and Iowa rivers. The ground rain data alone goes into a reference model experiment that creates a flood forecast. Then the researchers will see how well the other flood forecasts that include data from satellites and even other weather prediction models do in comparison.
For the GPM mission, the results of these comparisons mean a better interpretation of the raw rain data and improved understanding of the rainfall estimates the new satellite will provide from space. For the Iowa Flood Center, Krajewski said, the benefit could be closer to home: "Our hope is that with all that information, we can really improve our flood forecasting models."
###
Follow the IFloodS Campaign Blog
http://earthobservatory.nasa.gov/blogs/fromthefield/category/iowa-flood-studies/
To learn more about the IFloodS field campaign, visit:
http://pmm.nasa.gov/ifloods
http://iowafloodcenter.org/projects/ifloods/
To learn more about GPM, visit:
http://www.nasa.gov/gpm or http://pmm.nasa.gov
[ | E-mail | Share ] ?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Public release date: 30-Apr-2013 Share ] Contact: Rani Gran
rani.c.gran@nasa.gov
301-286-2483
NASA/Goddard Space Flight Center
Ground data now being collected in northeastern Iowa by the Iowa Flood Studies experiment will evaluate how well NASA's Global Precipitation Measurement (GPM) mission satellite rainfall data can be used for flood forecasting.
GPM is an international satellite mission that will set a new standard for precipitation measurements from space, providing worldwide estimates of precipitation approximately every three hours. The GPM Core Observatory, provided by NASA and mission partner the Japan Aerospace Exploration Agency, will launch in early 2014. Scientists are already at work, however, developing the methods for turning satellite observations into meaningful data by measuring rainfall with existing satellites and rain gauges in the field, and then using that data for societal applications, such as flood forecasting and monitoring of water resources.
"We're trying to figure out how well our satellites estimate rainfall," said Walt Petersen, GPM ground validation scientist at NASA's Wallops Flight Facility in Virginia. "This study is unique in that it takes space-borne observations, it takes ground-based observations, and it brings those things into a modeling framework that should further our ability to predict flooding."
With rainfall estimates in hand, the science teams input them into flood prediction computer models and then evaluate how the rain estimates and their uncertainties affect the outcome of the flood forecast, said Petersen. Rainfall estimates of water content and intensity are vital inputs for forecasters who need that information to determine whether or not streams and rivers will flood and impact people living in the floodplain.
The field campaign, which is taking place from May 1 to June 15, is a partnership between NASA and the Iowa Flood Center at the University of Iowa, Iowa City. The Iowa Flood Center was established after the unprecedented flooding, particularly of Cedar Rapids, in 2008, said Witold Krajewski, the Center's director. Since then, the Center has improved field monitoring of stream and river height and developed a 'library' of flood inundation maps of where flooding may occur for some of Iowa's most vulnerable communities.
Many variables go into flood prediction, said Krajewski, including soil type and moisture, stream and river geography, and land use. Some variables are difficult to measure, such as how water flows underground after it soaks into the ground. Rainfall, while challenging, is one of the easier variables to measure because we can see it, he said.
The field campaign, called the Iowa Flood Studies experiment, or IFloodS, will collect data from a vast network of ground instruments as well as instruments on satellites passing overhead. The ground instruments include rain gauges; instruments to measure soil moisture and temperature; disdrometers, which measure raindrop numbers, sizes and shapes as they reach the surface; and advanced precipitation radars, which measure the characteristics of rain as is falls.
The advanced NASA Polarimetric (NPOL) precipitation radar being deployed just south of Waterloo, Iowa, will look at rainfall above a line of ground instruments stretching toward Iowa City. The NPOL radar scans a volume of the atmosphere as it transmits pulses oriented in two directions, horizontal and vertical, returning three-dimensional images that provide information for distinguishing the size, shape and distribution of raindrops within rainclouds. This view will help scientists understand the physics of rainfall, essentially where ice, rain and sleet occur in clouds, how precipitation particles form, grow and interact, and how the distribution of raindrops changes as a function of height, said Petersen.
"The physics in the air column, all the way to the top of the cloud, affect how that rain forms and falls and how much rain you get at the surface," he said. Better understanding of the physics will improve rainfall estimates from space.
A second NASA ground radar, called the Dual-Frequency, Dual-Polarimetric Doppler Radar (D3R), will collect data at similar frequencies to the Dual-frequency Precipitation Radar that will fly on the upcoming GPM Core Observatory. The orbiting satellites that will collect data as they pass over Iowa each carry an instrument called a microwave radiometer, the same type of instrument as the Core's second instrument, the GPM Microwave Imager.
The satellite data used during the campaign will be from NASA's Tropical Rainfall Measuring Mission (TRMM), CloudSat, and Suomi National Polar Partnership (NPP) satellites; NOAA's 16, 18, and 19 weather satellites; the Defense Satellite Monitoring Program (DSMP) satellites; JAXA's Global Change Observation Mission-Water (GCOM-W1) satellite; and the European Union's METOP A and B weather satellites. In addition, the geosynchronous GOES satellite products will be analyzed.
"Here in Iowa, we have basins of varied sizes that are well instrumented compared to some other parts of the country," said Krajewski. That's one reason that NASA chose Iowa for its field campaign, according to Petersen. Krajewski added, however, that with the additional instruments from NASA, "collectively we will be gathering data that will be without precedent."
The GPM and IFloodS science teams will first use the ground radar and gauge data to develop a reference for how much rain is actually falling out of the sky, said Petersen. They can then compare the ground reference to those of the satellite estimates of rainfall. Secondly, both sets of data are fed into flood forecasting models for the Cedar and Iowa rivers. The ground rain data alone goes into a reference model experiment that creates a flood forecast. Then the researchers will see how well the other flood forecasts that include data from satellites and even other weather prediction models do in comparison.
For the GPM mission, the results of these comparisons mean a better interpretation of the raw rain data and improved understanding of the rainfall estimates the new satellite will provide from space. For the Iowa Flood Center, Krajewski said, the benefit could be closer to home: "Our hope is that with all that information, we can really improve our flood forecasting models."
###
Follow the IFloodS Campaign Blog
http://earthobservatory.nasa.gov/blogs/fromthefield/category/iowa-flood-studies/
To learn more about the IFloodS field campaign, visit:
http://pmm.nasa.gov/ifloods
http://iowafloodcenter.org/projects/ifloods/
To learn more about GPM, visit:
http://www.nasa.gov/gpm or http://pmm.nasa.gov
[ | E-mail | Share ] ?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Source: http://www.eurekalert.org/pub_releases/2013-04/nsfc-nuo043013.php
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Janos Starker dies: A renowned cellist, Janos Starker survived a Nazi concentration camp and became a world-class musician and teacher.
Janos Starker playing Bach: C Major Suite, during a 1989 recital in Tokyo, Japan.Grammy Award-winning cellist Janos Starker has died after months of declining health. He was 88.
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Alain Barker, a spokesman for the Jacobs School of Music at Indiana University, said Starker died Sunday at his Bloomington home in the presence of family members.
Starker won a 1997 Grammy Award for best instrumental solo performance for a recording of Bach cello suites.
Starker made his professional debut at 14. He immigrated to the U.S. in 1948 and played for the Dallas Symphony, Metropolitan Opera Orchestra and Chicago Symphony before joining Indiana University in 1958.
In an NPR rememberance, Starker said teaching was his calling.
"I've been caught confessing that basically I was born to be a teacher," he said. "People question the validity of it, because I played all those 3, 4, 5,000 concerts in my life. But the fact is, I think I was put on earth to be a teacher."
The New York Times wrote of Starker: "The chief hallmark of his playing was a conspicuous lack of schmaltz. Effusive sentiment is an inherent risk of the cello, with its thundering sonorities and timbre so like the human voice. He also shunned the dramatic head tossing and body swaying to which many cellists incline.... Unlike many acclaimed string players, Mr. Starker used a lean, judicious vibrato ? the minute, rapid variations in pitch by the left hand that can enrich a note?s sound but can also border on the histrionic. Excessive vibrato, he said, was like ?a woman smearing her whole face with lipstick.?
He was born to Jewish parents in Budapest on July 5, 1924, and spent three months in Nazi concentration camps.
Survivors include his wife, Rae, and two daughters.
Copyright 2013 The Associated Press.
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During the festival from 2 PM to 10 PM everyone is invited to benefit from the quality services & free health checkups, interactive group activities, demonstrations and informative sessions and wellness & fitness exhibition which is all provided by certified medical professionals and experts in the fields.
Dubai Outlet Mall's Health & Wellness Festival 2013 will be a multifaceted event, featuring various medical & wellbeing procedures and services including but not limited to:
?Blood Pressure Screening
?Blood Sugar Checkup
?Body Composition Analysis
?Personalized Weigh Loss Consultation & Nutritional tips
?Breast Cancer info & Symptoms Awareness
?Diabetes Screening
?Hypertension Consultation
?Hepatitis Check up
?Podiatry Screening
?Bone Health & intensity check up
?Spinal & posture check up
?Physiotherapy
?Eye Check up
?Dental Check up
?Spa Wellness & Rejuvenating
?Fitness tips & Demonstration
This event is providing an opportunity for everyone to interact with medical experts and health care professionals in a calming and fun environment.
Visitors are advised to prepare their concerns and questions as medical and wellbeing experts shall be available to answer their questions. Doctors and experts will talk about preventing diseases, identifying signs & symptoms promptly to avoid health problems, intensifying efforts to encourage healthy living & family wellbeing.
Families, residents and tourists will not only get all the mentioned checkups and counseling completely free of charge but there will be lots of gifts, goody bags and prizes to be won from different medical centers and clinics offering complimentary health and beauty services.
Source: http://www.ameinfo.com/dom-association-uae-ministry-health-organise-339712
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Medical school program opens new medical school, creates job opportunities
St. Louis, MO (I-Newswire) April 30, 2013 - Western Michigan University School of Medicine (WMed) is seeking Family Medicine faculty as well as an Osteopathic Family Medicine Program Director to join the Department of Family and Community Medicine. Western Michigan University is in the process of opening a new medical school in Kalamazoo, which will provide faculty members with the unique opportunity to be actively involved in the formation of a new school. Candidates will join a collegial, stable group that is passionate about teaching, but enjoys work / life balance as well.
The dually accredited (AOA and ACGME) WMed Family Medicine program recently increased from six to eight residents per year. It has expanded into a neighborhood Federally Qualified Health Center and developed an accredited Patient Centered Medical Home. ?We are committed to providing a quality educational experience for our residents and medical students,? says Allan Wilke, MD, MA, Founding Chair and Residency Program Director in the Department of Family and Community Medicine at WMed.
Western Michigan?s faculty is currently comprised of seven WMed faculty as well as twelve part-time community-based faculty members. Call is one week in five and residents take first call, giving faculty members the opportunity to enjoy all that Kalamazoo and surrounding areas have to offer, including close proximity to Lake Michigan. Residents of the community benefit from the Kalamazoo Promise, which provides Kalamazoo Public School graduates with a four-year scholarship, which includes 100% tuition and mandatory fees at any of Michigan?s public universities or community colleges.
The Western Michigan University School of Medicine is affiliated with two hospitals that are approximately 350 beds each. Combined with the outpatient clinics, WMed attracts patients from a wide service area in southwest Michigan. The state-of-the-art ambulatory care/teaching center sees more than 68,000 annual visits in its clinics and offers a full range of on-site ancillary services. This provides a satisfying environment for both patients and providers. WMed is a fully wired campus with comprehensive electronic medical records and offers numerous opportunities for clinical research, if desired.
For more information, contact Courtney Becker at 314-236-4401, cbecker@cejkasearch.com; or visit http://jobs.cejkasearch.com
About Cejka Search
Cejka Search is a nationally recognized physician, health care executive, advanced practice and allied health search firm providing services exclusively to the health care industry for more than 30 years. Cejka Search recruits top health care talent for organizations nationwide through our team of experienced professionals, award-winning recruitment technology and commitment to service excellence. Cejka Search is a Cross Country Healthcare, Inc. company, a leading provider of health care staffing services in the United States.
For more information visit http://www.cejkasearch.com, contact Michelle Kuehler (Black Twig Communications), 314-536-8909, or Mary Barber (Cejka Search), 314-236-4410.
Source: http://www.i-newswire.com/expanding-family-medicine-program/221070
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Public release date: 30-Apr-2013 Share ] Contact: Alisa Z Machalek
alisa.machalek@nih.gov
NIH/National Institute of General Medical Sciences
Cells ingest proteins and engulf bacteria by a gymnastic, shape-shifting process called endocytosis. Researchers at the National Institutes of Health revealed how a key protein, dynamin, drives the action.
Endocytosis lets cells absorb nutrients, import growth factors, prevent infections and accomplish many other vital tasks. Yet, despite decades of research, scientists don't fully understand this membrane remodeling process. New research reveals, on the real-life scale of nanometers, how individual molecules work together during a single act of endocytosis.
"We've discovered new details about a basic process used in all sorts of ways by every cell in the body," said co-author Joshua Zimmerberg, M.D., Ph.D., head of the Program in Physical Biology at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), where the research was conducted. "It's the culmination of a 30-year journey."
The research was led by Vadim Frolov, Ph.D., a former postdoctoral fellow in Dr. Zimmerberg's lab. It appears in a Science paper co-authored by an international team of researchers in the United States, Spain, Russia and India.
In addition to funding Dr. Zimmerberg, NIH also supported the work through a grant from the National Institute of General Medical Sciences (NIGMS) to co-author Sandra Schmid, Ph.D. at the University of Texas Southwestern Medical Center in Dallas. Dr. Schmid is an expert on dynamin.
Scientists have known for years that dynamin plays the major role in endocytosis. After other molecules known as coat proteins pinch the cell's membrane to form an inward-puckering sac, dynamin wraps, python-like, around the neck of the sac and squeezes it tightly. A jolt of energy from a molecule called GTP severs the neck, releasing a free-floating bubble, called a vesicle, inside the cell, and sealing the cell's outer membrane shut. All the while, neither the cell nor the vesicle leak any of their contents.
Drs. Zimmerberg, Schmid and colleagues discovered how the cell overcomes a seemingly insurmountable energy barrier to accomplish this feat. It's not a matter of brute force, as previously suspected, but something much more zen-likemolecular cooperation.
Neck severing starts when dynamin dips slightly into the pliable cell membrane. Lipids (oily molecules) in the membrane move aside, shifting their tails to accommodate the protein. This molecular crowding stresses the membrane, further constricting the neck of the developing vesicle.
Then GTP finishes the job. But not, as you might expect, with a fatal tug of the dynamin noose. Rather the opposite: Like a yoga instructor, GTP encourages the membrane to relax, despite its extreme stress. In the middle of this state of relaxation, the vesicle suddenly pinches off.
In trying to understand this counterintuitive move, the researchers speculate that GTP melts the inside of dynamin a bit, turning the protein into a flexible scaffold that stabilizes the membrane while the lipids rearrange themselves.
"We see no other way to lower the energy barrier to remodeling without having any leaks," states Dr. Frolov, who formulated the idea.
The researchers also found that, without access to GTP, dynamin will keep growing, twisting three or four times around the neck of the sac. When GTP is present (as is the case in living organisms), it only lets dynamin coil once or twice before it snaps off the vesicle.
All of this information helps scientists better understand a process critical to life.
Genetic defects in endocytosisand the reverse process, exocytosisare linked to a host of human diseases, including muscular dystrophy, Alzheimer's disease, leukemia and many others. In addition, some parasites and other pathogens can hijack endocytosis, commandeering the process to enter and infect human cells.
Dr. Zimmerberg is bringing his basic research findings to the clinic. He is studying changes in muscle cell membranes in people who have an adult-onset form of muscular dystrophy. In the disease, the membrane around muscle cells weakens and tears. Eventually, cells with damaged membranes die, leaking a number of enzymes into the bloodstream. Dr. Zimmerberg hopes to identify changes in blood chemistry that shed light on the disease process and point to possible new treatments. The study soon will begin recruiting patients as volunteers.
###
This research was supported in part by the intramural program of the NICHD and by NIGMS grant GM42455.
About the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD):
The NICHD sponsors research on development, before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation. For more information, visit the Institute's website at http://www.nichd.nih.gov/.
About the National Institute of General Medical Sciences (NIGMS):
NIGMS supports basic research to increase our understanding of life processes and lay the foundation for advances in disease diagnosis, treatment and prevention. For more information on the institute's research and training programs, see http://www.nigms.nih.gov.
About the National Institutes of Health (NIH):
NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.
[ | E-mail | Share ] ?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Public release date: 30-Apr-2013 Share ] Contact: Alisa Z Machalek
alisa.machalek@nih.gov
NIH/National Institute of General Medical Sciences
Cells ingest proteins and engulf bacteria by a gymnastic, shape-shifting process called endocytosis. Researchers at the National Institutes of Health revealed how a key protein, dynamin, drives the action.
Endocytosis lets cells absorb nutrients, import growth factors, prevent infections and accomplish many other vital tasks. Yet, despite decades of research, scientists don't fully understand this membrane remodeling process. New research reveals, on the real-life scale of nanometers, how individual molecules work together during a single act of endocytosis.
"We've discovered new details about a basic process used in all sorts of ways by every cell in the body," said co-author Joshua Zimmerberg, M.D., Ph.D., head of the Program in Physical Biology at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), where the research was conducted. "It's the culmination of a 30-year journey."
The research was led by Vadim Frolov, Ph.D., a former postdoctoral fellow in Dr. Zimmerberg's lab. It appears in a Science paper co-authored by an international team of researchers in the United States, Spain, Russia and India.
In addition to funding Dr. Zimmerberg, NIH also supported the work through a grant from the National Institute of General Medical Sciences (NIGMS) to co-author Sandra Schmid, Ph.D. at the University of Texas Southwestern Medical Center in Dallas. Dr. Schmid is an expert on dynamin.
Scientists have known for years that dynamin plays the major role in endocytosis. After other molecules known as coat proteins pinch the cell's membrane to form an inward-puckering sac, dynamin wraps, python-like, around the neck of the sac and squeezes it tightly. A jolt of energy from a molecule called GTP severs the neck, releasing a free-floating bubble, called a vesicle, inside the cell, and sealing the cell's outer membrane shut. All the while, neither the cell nor the vesicle leak any of their contents.
Drs. Zimmerberg, Schmid and colleagues discovered how the cell overcomes a seemingly insurmountable energy barrier to accomplish this feat. It's not a matter of brute force, as previously suspected, but something much more zen-likemolecular cooperation.
Neck severing starts when dynamin dips slightly into the pliable cell membrane. Lipids (oily molecules) in the membrane move aside, shifting their tails to accommodate the protein. This molecular crowding stresses the membrane, further constricting the neck of the developing vesicle.
Then GTP finishes the job. But not, as you might expect, with a fatal tug of the dynamin noose. Rather the opposite: Like a yoga instructor, GTP encourages the membrane to relax, despite its extreme stress. In the middle of this state of relaxation, the vesicle suddenly pinches off.
In trying to understand this counterintuitive move, the researchers speculate that GTP melts the inside of dynamin a bit, turning the protein into a flexible scaffold that stabilizes the membrane while the lipids rearrange themselves.
"We see no other way to lower the energy barrier to remodeling without having any leaks," states Dr. Frolov, who formulated the idea.
The researchers also found that, without access to GTP, dynamin will keep growing, twisting three or four times around the neck of the sac. When GTP is present (as is the case in living organisms), it only lets dynamin coil once or twice before it snaps off the vesicle.
All of this information helps scientists better understand a process critical to life.
Genetic defects in endocytosisand the reverse process, exocytosisare linked to a host of human diseases, including muscular dystrophy, Alzheimer's disease, leukemia and many others. In addition, some parasites and other pathogens can hijack endocytosis, commandeering the process to enter and infect human cells.
Dr. Zimmerberg is bringing his basic research findings to the clinic. He is studying changes in muscle cell membranes in people who have an adult-onset form of muscular dystrophy. In the disease, the membrane around muscle cells weakens and tears. Eventually, cells with damaged membranes die, leaking a number of enzymes into the bloodstream. Dr. Zimmerberg hopes to identify changes in blood chemistry that shed light on the disease process and point to possible new treatments. The study soon will begin recruiting patients as volunteers.
###
This research was supported in part by the intramural program of the NICHD and by NIGMS grant GM42455.
About the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD):
The NICHD sponsors research on development, before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation. For more information, visit the Institute's website at http://www.nichd.nih.gov/.
About the National Institute of General Medical Sciences (NIGMS):
NIGMS supports basic research to increase our understanding of life processes and lay the foundation for advances in disease diagnosis, treatment and prevention. For more information on the institute's research and training programs, see http://www.nigms.nih.gov.
About the National Institutes of Health (NIH):
NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.
[ | E-mail | Share ] ?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Source: http://www.eurekalert.org/pub_releases/2013-04/niog-mrw042913.php
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While we're used to connected hard drives that share their contents with phones and tablets, the reverse isn't common -- why don't many of these drives safeguard our mobile content from the start? Toshiba is as baffled as we are, so it's launching its Canvio Connect portable drive with handheld access in mind. While the USB 3.0 disk has no built-in networking of its own, a software bundle for Macs and PCs (we've confirmed that it's Pogoplug) lets travelers back up photos and videos from their Android and iOS devices, reach the drive's files through the internet and partake in 10GB of free cloud storage. The new Canvio can also serve as a traditional external drive for computers, although it's still improved in that space when the enclosure is about a third shorter than that of its predecessors. Toshiba expects the mobile-savvy Connect to arrive in mid-May at prices ranging from $99 for a 500GB model through to $190 for a 2TB version.
Filed under: Storage, Internet
Source: Toshiba
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