The simple ‘thump-thump, thump-thump’ rhythm of a heartbeat can be quite deceiving. With each heartbeat or cardiac cycle, the heart pumps in blood and then pushes it back out.
One half of the heart receives the deoxygenated (venous) blood used by our body and then sends it to our pulmonary system (lungs etc.) to again be enriched with oxygen. The other half of the heart receives freshly oxygenated (arterial) blood from the pulmonary system and pumps it into circulation throughout our body.
The cycle repeats throughout our lives. It is estimated that the heart beats some 35 million times in a year and more than two and a half billion times in an average lifetime without ever pausing to rest.
Each heartbeat must be precisely calibrated. One small deviation can bring sudden death.
So how does the heart pull this off?
An international team of researchers, writing in a study that was published in the inaugural issue of the journal Science Advances, have identified a specific protein called myosin-binding protein C (cMyBP-C) that they found plays a pivotal role in keeping the heart beating in reliable time.
The scientists discovered that the position of this protein within the heart’s muscle cells allows the heart’s muscle fibers to work together in perfect synchronization, which is vital to ensure the heart operates properly.
If the tiny protein should break down, the researchers found that the heart can malfunction in way that can lead to sudden death causing arrhythmias, or irregular heartbeat.
On the other hand, the researchers said their finding also suggests that making adjustments to the cMyBP-C protein could help resolve a number of heart problems and may someday be used to treat people with potentially deadly heart conditions.
Two of the study’s lead researchers, David Warshaw, Ph.D., Michael Previs, Ph.D., both molecular physiologists from the University of Vermont’s Cardiovascular Research Institute, used powerful microscopes to look inside a part of heart muscle tissue called the sarcomere.
The sarcomere, which is about one fiftieth the diameter of a human hair, expands and contracts with every heartbeat. For the heart to beat properly, trillions of these sarcomeres must contract and expand simultaneously.
“To pump blood efficiently, they all have to be doing it at the same time,” Warshaw said.
Two proteins called myosin and actin help the sarcomere expand and contract. Myosin acts like a motor that pushes or pulls the rope-like actin. In turn, actin pulls in the sarcomere and then releases it out so it can refill with blood.
Since the myosin protein is always trying to snatch and move the actin, it needs some kind of control mechanism to make sure that it’s grabbing and moving actin at the precise time when the sarcomere needs to contract.
The cMyBP-C protein, located at the center of the sarcomere, regulates the two proteins by balancing the myosin — slowing or speeding its interaction with actin as needed — to maintain the precise timing of the sarcomere’s expansion/contraction.
The researchers were able to make their findings by examining the normal heart muscle of animals. Now, the plan to find out what goes wrong with cMyBP-C protein in a diseased heart.
Once all of the research is complete, scientists then would be able to develop cMyBP-C-based pharmaceutical treatments to help repair unhealthy hearts.
Heart Beating (National Institute of Genetics, Japan)
California has been contending with one of the most severe droughts on record. Now a new study is predicting that in the second-half of our current century, the U.S. Great Plains and the Southwest, including California, will face what could be considered “mega-drought” conditions that will be worse than anytime over the past 1,000 years.
The study, written by the Earth Institute at New York’s Columbia University, suggests that the drying conditions leading to the severe drought will be primarily driven by human-generated global warming.
While there already have been numerous past studies that predicted that global warming could dry the Southwest, this new paper is the first to say that the severe drying conditions could be way beyond the driest conditions since ancient time.
According to the U.S. Drought Monitor, which has been produced by a number of U.S. government agencies, eleven out of the past 14 years have been considered drought years in much of the Western U.S., which includes California, Nevada, New Mexico and Arizona, as well as Texas and Oklahoma in the U.S. Southern Plains.
NASA said the current drought is directly affecting more than 64 million people in parts of the U.S. that include Southwest and Southern Plains. Many more people in the agricultural regions of those areas are indirectly affected by the dry spell as well.
I’m sorry if this story seems fishy. But, scientists, writing in the American Chemical Society’s journal, “Applied Materials and Interfaces”, suggest that tilapia, a popular dinner fish, can be used to create effective wound dressings.
Experimenting on rats, the researchers found that the fish’s collagen — a major structural protein — when incorporated into a wound dressing, can help repair damaged skin without incurring an immune reaction.
The scientists also found that similar protein dressings created from the collagen of mammals such as cows and pigs could possibly transfer conditions such as foot-and-mouth disease.
After their successful experiments on rats, researchers now believe that their fish protein dressing could be used to effectively treat humans in the future.
Anyone who has undergone a Magnetic Resonance Imaging (MRI) examination knows that the procedure, especially when performed with units where the patient is placed inside a tight tube, can often induce varied levels of stress, claustrophobia, or outright panic.
The patient must remain absolutely still throughout most of the procedure in order to ensure a successful MRI exam. This can be quite difficult given the loud noises produced by some MRI machines and confinement in such tight quarters.
But in the future, those undergoing MRI scans could have a less stressful experience, thanks to a new instructional DVD developed by an international team of scientists.
The DVD is in two sections. The first section, called ‘Preparation for MRI’, includes various information about the exam, such as what to expect in an MRI scan and what the scan would feel like. This portion also features a demonstration of a patient undergoing a scan, as well as others who talked about their MRI scan experience.
The second section of the DVD provides some detailed relaxation techniques that can be performed by examinees before and during their scan.
Those given the DVD were asked to watch it at least once before their scan appointment.
To test its effectiveness, the researchers provided the DVD to 41 people who had an appointment for an MRI scan. Of those 41 people, scientists found that 35 wound up having satisfactory exams. They were able to remain in the scanner for the entire procedure while keeping still enough for the machine to produce high quality images.
Do you think you have a singing voice that makes dogs howl?
Don’t worry because new research shows that practice does indeed make perfect … pitch that is.
Moreover, the research shows that even if you were born with perfect pitch and are a wonderful singer, if you don’t practice or sing frequently you could lose that ability over time.
Researchers at Northwestern University made the discovery and have published their results in a new paper.
The study’s lead researcher Steve Demorest, a professor of music education at Northwestern’s Bienen School of Music says that developing the ability to sing on key may be the same as the kind of practice it takes to become a skilled instrumentalist.
“No one expects a beginner on violin to sound good right away, it takes practice, but everyone is supposed to be able to sing,” Demorest said in a University press release. “When people are unsuccessful they take it very personally, but we think if you sing more, you’ll get better.”
The new Northwestern study tested the singing accuracy (ability to sing on key) of volunteers in three age groups: kindergarteners, sixth graders and college-aged adults.
Rather than have members of each group sing a particular song, the researchers had the volunteer singers listen to four varied repetitions of a single musical note and then sing back what they had heard. In another test the singers were asked to sing back what there heard in scattered intervals.
The researchers used similar methods to gauge the singing accuracy of each of the three groups of volunteers.
After testing each group, the researchers studied their measurement data and found that those who were in the kindergarten to late elementary school groups showed considerable improvement in singing accuracy.
The young-adults didn’t do so well on the tests, compared with their grade school colleagues. The college-age crowd performed their tests at the same level as the kindergarten volunteers in two of three tests given. The researchers said these results suggested the “use it or lose it” aspect of maintaining singing accuracy.
“Our study suggests that adults who may have performed better as children lost the ability when they stopped singing, said Demorest.
But in all fairness the elementary school age children are also given a good deal of musical instruction that’s focused on mostly singing.
As a student gets older and progresses from elementary into higher grades, music, especially singing becomes more of an elective study with only 34 percent of U.S. students actively involved in musical and/or singing instruction and participation. The number of students doing so drops even further as they progress toward high school graduation.
Although older students tend to sing more accurately than younger children, there’s not a lot of data on the singing ability of those between 12 and 18 years old, which the researcher call “an especially formative period, when voices change and there’s high interest in concerts and other forms of musical expression.”
The issue is further complicated since there’s really not a set standard of what accurate singing is nor is there any way at present to reliably measure such abilities.
So Demorest and a colleague and co-author of the study Peter Pfordresher the director of the Auditory Perception and Action Lab at the University at Buffalo in New York, are leading an endeavor that would create a measure of singing accuracy through internet based tools.
Once the online tools are completed, Demorest and Pfordresher hope that music teachers will use them to help children who are struggling with singing as well as by adults who would be able to test their own singing ability by a set measure.
Demorest did acknowledge that the being able to sing on key is easier and more natural for some people than others. But he also said it’s a skill people can learn and, with practice, be able to develop.
One of our solar system’s most fascinating planets is Saturn. It’s the 2nd largest planet, after Jupiter. But what makes Saturn stand out from the others is the dazzling system of rings that surround it.
Recently, a Dutch and an American astronomer found that an extrasolar object, discovered back in 2012, is surrounded by a ring system that’s 120 million kilometers in diameter, which is more than two hundred times as large as the rings circle Saturn.
The astronomers are still trying to determine whether the object, dubbed J1407b, is a large Jupiter-like planet or a brown dwarf, which is a celestial body that began forming as a star, but wasn’t able to sustain the needed hydrogen-1 fusion to make it a main sequence star.
The ring system surrounding J1407b, the first of its kind to be found outside our solar system, contains of over 30 rings, with each of them tens of millions of kilometers in diameter. The astronomers believe that the material in the ring system probably contains about an Earth’s worth of mass.
The “exo-object” orbits a very young – only about 15 million years old – Sun-like star called J1407 some 400 light years away.
Back in 2012 a team led by Dr. Eric Mamajek, an astronomer from New York’s University Of Rochester, studied a number of sun-like stars a few hundred light-years away from data gathered in 2007 by the UK’s SuperWASP (Wide Angle Search for Planets) extra-solar detection program. By chance they happened to notice that one of the stars flickered on and off over a two month period.
The unusual changes in the brightness of the star – “flickering” – prompted Mamajek and his team to consider a number of different ideas of just what could be causing the variations. But in the end, the only model that made sense was one that had a giant planet-like object with a huge array of rings around it.
This new analysis, according to Mamajek, provided the researchers with greater detail to better study the structure of the rings around J1407b.
For the 2012 study the researchers produced a model that included four rings. But that model, while close, didn’t quite completely fit all of their data. A newer model crafted from the reanalyzed data features over 30 rings.
The new model also shows very clean gaps with very abrupt changes within the density of the rings.
Similar gaps found in Saturn’s ring system indicate the presence of a moon. Mamajek explained that either there’s a moon actually carving out the gap or the gravitational effect of a moon further out or in that’s creating the interruption in the rings.
“The gaps we see are very clean, so there must be something in there that’s gobbling up all the material or dynamically throwing it out of the system,” said Mamajek.
The ring system itself may actually be a protoexosatellite disk or circumplanetary disk, according to the researchers.
“I think what we’re seeing here is the stage where moons are actually forming,” said Mamajek.
Video showing a demonstration of the the computer model that fits the light curve of the star J1407 seen in SuperWASP data in 2007. (M. Kenworthy/Leiden)
Mamajek said he and his team have been working with the American Association of Variable Star Observers (AAVSO), a large amateur astronomy organization, and that amateur astronomers have already contributed valuable assistance to the their findings. Any interested amateur astronomers who would like to help with the team’s continuing work in monitoring the J1407 system can do so through the AAVSO.
The new Kenworthy/Mamajek study outlining their findings has been accepted for publication in the Astrophysical Journal.
Dr. Eric Mamajek talked about this “Super Saturn” on a recent radio edition of Science World. You can listen to the interview in the player below.
A team of British geologists has developed a new way to learn something about the early days of our solar system.
Since meteorites are fragmented pieces of asteroids that have fallen to Earth, testing the magnetic field of the meteorite can provide some information about its parent asteroid.
Asteroids are as old as the solar system itself. Studying objects that originate some 4.5 billion years ago can tell scientists something about our own origin as a planet, and perhaps our fate.
The researchers, using the BESSY II synchrotron at Helmholtz-Zentrum Berlin for Materials and Energy research center, fired a powerful beam of x-rays at a meteorite to capture information that was stored within miniature magnetic regions of the ancient space rock.
Writing in a new study published by the journal Nature, the research team from the UK’s University of Cambridge said that their findings provide a look at what could happen to Earth’s magnetic field billions of years from now when its core completely freezes solid.
Some scientists believe that the Earth’s core began its process of freezing less than a billion years ago, which is to core only began to freeze relatively recently in geological terms, maybe less than a billion years ago.
According to the research team’s leader, Dr. Richard Harrison of the University of Cambridge’s Department of Earth Sciences, we have no reason to worry about our home planet’s core completely freezing over anytime soon because it will take billions of years for that to happen. Besides, Harrison adds, chances are that the Sun will get us first.
Greenland’s Ice Sheet Is Melting From Above and Below its Surface
Two newly published studies have suggested that atmospheric climate change is quickly melting Greenland’s ice sheet, which makes up about 80 percent of its landmass. The studies find that the melting is taking place not only at the top of the ice sheet’s surface but also from the bottom.
The studies also found that two lakes of meltwater that formed beneath Greenland’s ice sheet have quickly drained away.
In one study, published in the open-access journal The Cryosphere, researchers said that one of the lakes, which had held billions of liters of meltwater, had emptied out leaving a crater behind that’s 1.5 kilometers wide.
Researchers writing in the other study, published by the journal Nature, said that within the last two years the second sub-glacial lake filled up and emptied twice.
Scientists say that as the meltwater fills the sub-glacial lakes it brings with it stored heat – called latent heat – from the surface’s comparatively warm atmosphere which then softens the surrounding ice.
The researchers suspect that as the melt-water makes it way from the surface to the base of the ice sheet it’s causing naturally formed drainage tunnels on Greenland’s coasts to expand to areas further inland.
These expanded drainage tunnels then bring heat and water to areas of the ice sheet that had been frozen to bedrock, possibly causing the ice to melt faster.
A lot of attention has been focused on cybersecurity lately especially after hackers recently broke into the computer systems at Sony Pictures Entertainment.
A group of scientists from the U.S. and China have come up with a novel and cost effective way to protect computer systems.
The researchers developed what has been described as a “self-cleaning, self-powered smart keyboard that can identify computer users by the way they type.”
Writing in the American Chemical Society’s journal, Nano, the developers of the new “smart keyboard,” could help keep unauthorized users from obtaining direct access to computers.
The new device senses various typing patterns such as the speed and amount of pressure that a user applies to the keyboard which creates a special user profile that allows the keyboard to distinguish one user from another.
So even if someone was to steal your password the keyboard wouldn’t allow access to the computer since the typing profile is different.
The researchers add that the keyboard keeps itself clean because it is coated with a special surface that resists dirt and grime.
Nominations for the 2015 Academy Awards were announced last week. And while they may be among the best movies of the year, how many do you think will survive the test of time to become all-time classics.
Many movie goers would expect such factors such as a film’s box-office revenue, awards, and critical acclaims to be most significant.
But, researchers at Northwestern University in Illinois came up with a new way to accurately predict true classic and significant movies from others. Reporting their findings in the Proceedings of the National Academy of Sciences (PNAS), the researchers noted the frequency a particular film is referenced in other works — such as other movies or TV programs – is key.
“Movie critics can be overconfident in spotting important works, and they have bias,” said Luís Amaral, the leader of the study in a Northwestern press-release. “Our method is as objective as it gets.” Amaral is a professor of chemical and biological engineering at Northwestern and is co-director the university’s Northwestern Institute on Complex Systems.
In their study, Amaral and his colleagues sifted through the on-line Internet Movie Database (IMDb) and reviewed the entries of some 15,425 movies that were produced in the United States.
The researchers developed an automated method that thoroughly analyzed various subjective factors contained within the entries such as reviews from critics or if it had garnered any notable awards – Golden Globe and Academy Awards – as well as objective factors such as box office receipts and how often the film was cited in the future.
The Northwestern researchers found that their method of tallying how many times a movie was cited in other works was better at forecasting classic movies — especially those at least 25 years old –than other factors such a critical praise, awards and even box office receipts.
“There is something about a movie that is hidden to us, but there are measurable things, such as critic ratings, awards and referencing by other filmmakers, that hint at this hidden element — a movie’s significance,” said Amaral. “We find that ultimately it is the creators, the filmmakers themselves, who will determine which movies are important, not the expert critics.”
The researchers also found that the number of times a particular movie is referenced in other works can also predict its likelihood of being ‘culturally, historically, or aesthetically significant’ enough to be included in the prestigious U.S. National Film Registry.
The movies that had the most references over a period of many years and are also listed in the National Film Registry are “The Wizard of Oz,” “Star Wars,” “Psycho,” “Casablanca” and “Gone With the Wind.”
“Directors keep coming back to movies that are significant,” Amaral said. “If you show a little bit from ‘Pscyho,’ such as referencing the shower scene, you are putting that whole movie in front of the viewer of the new movie.”
The Northwestern research team is planning to use its newly developed automated analysis method to determine the true importance of various scientific papers, paintings and music.
Science World is VOA’s on-air and online magazine covering science, health, technology and the environment.
Hosted by Rick Pantaleo, Science World‘s informative, entertaining and easy-to-understand presentation offers the latest news, features and one-on-one interviews with researchers, scientists, innovators and other news makers.
Science World begins after the newscast on Friday at 2200, Saturday at 0300, 1100 and 1900 and Sunday at 0100, 0400, 0900, 1100 and 1200.
Science World may also be heard on some VOA affiliates after the news on Saturday at 0900 and 1100. (All times UTC).
Voice of America
330 Independence Ave., SW
Washington, DC 20237