Drug Study Shows Improvement in Major Orthopedic Surgery Care

July 10, 2010 By Leave a Comment

HAMILTON, Canada, July 9, 2010 /PRNewswire/ — An ultra-low-molecular-weight heparin called semuloparin has been found to reduce the incidence of venous thromboembolism in orthopedic surgery patients in a large clinical program being led by a steering committee chaired by McMaster University professor Dr. Alexander Turpie.

The follow-up analysis of three recently completed international clinical studies on short-term venous thromboembolism (VTE) protective medicine in patients undergoing major orthopedic surgery demonstrated that the ultra-low-molecular-weight heparin semuloparin reduced the incidence of VTE and all-cause death by 25 per cent compared to the commonly used therapy drug enoxaparin (a low-molecular-weight heparin).

Patients undergoing major orthopedic surgery are at increased risk of developing a dangerous blood clot that blocks veins, which is known as venous thromboembolism (VTE). Without treatment, the incidence of confirmed deep-vein thrombosis, blood clots within the veins of the legs and pelvis, is up to 40 to 60 per cent following major orthopedic surgery.

“This is a potential advance in orthopedic surgery compared to current VTE prophylaxis options,” said Turpie, a professor of medicine at the Michael G. DeGroote School of Medicine at McMaster.

The favourable benefit-to-risk profile observed with semuloparin compared to enoxaparin in the classic major orthopedic surgery model supports the further evaluation of semuloparin as VTE preventative therapy in other areas including oncology, as VTE is a known complication in patients with cancer. Patients suffering from cancer have a four to seven fold greater risk for VTE.

Turpie’s meta-analysis study reports results from 4,479 patients recruited in three orthopedic surgery studies in hip replacement (SAVE HIP), hip fracture (SAVE HIP-FRA) and knee replacement (SAVE KNEE). The objective of the three studies was to assess once-daily preventative treatment with semuloparin (20 mg) compared to enoxaparin (40 mg daily in hip, and 30 mg twice-daily for knee) for seven to 10 days.

The results of the SAVE program in orthopedic surgery were presented today at the 21st International Congress of Thrombosis in Milan, Italy, and organized by the Mediterranean League Against Thromboembolic Diseases.

Turpie is chairing the steering committee for the SAVE program, an international series of studies. The SAVE program is supported by sanofi-aventis, producer of semuloparin.

Semuloparin’s benefit-to-risk profile in cancer is currently being investigated in two ongoing phase three clinical studies. SAVE ONCO evaluates semuloparin in patients with cancer undergoing chemotherapy. SAVE ABDO assesses the benefits of semuloparin in major abdominal surgery, mainly cancer surgery. Semuloparin is a selectively engineered ultra-low-molecular-weight heparin.

SOURCE McMaster University

Filed Under: International News Tagged With: , , , , , , , , , , , , , , , , , , ,

Short bursts of intensive exercise as good as hours of training

March 13, 2010 By Leave a Comment

Washington, Mar 13 (ANI): The secret to staying fit is doing less exercise. Shocked? Well, a new study says short but intensive bursts of exercise lasting ten minutes are as effective as good as hours of training in fighting flab.

Boffins who have been studying interval training have found that it not only takes less time than what is typically recommended, but the regimen does not have to be “all out” to be effective in helping reduce the risk of such diseases at Type 2 diabetes.

The study appears in the March issue of The Journal of Physiology.

“What we”ve been able to show is that interval training does not have to be ”all out” in order to be effective and time-efficient,” says Martin Gibala, professor and chair of the Department of Kinesiology at McMaster University. “While still a very demanding form of training, the exercise might be more achievable by the general public—not just elite athletes—and it certainly doesn”t require the use of specialized laboratory equipment.”

Since Gibala”s first study on interval training was published five years ago, a growing body of research has zeroed in on this particular style of exercise in which you train hard but for less time.

Previous research by the McMaster group involved 30 seconds of maximal pedaling on a special bike followed by four minutes of recovery, and repeated 4-6 times. The new study involves eight to 12 one-minute bouts of exercise on a standard stationary bicycle at a relatively lower intensity with rest intervals of 75 seconds, for a total of 20-25 minutes per session. The workload was still above most people”s comfort zone —about 95percent of maximal heart rate — but only about half of what can be achieved when people sprint at an all-out pace.

“That is the trade-off for the relatively lower intensity,” says Gibala. “There is no free lunch; duration must increase as intensity decreases.”

While the total amount of exercise performed was higher than in Gibala”s previous interval training studies, the overall time commitment was still lower than what is typically recommended by public health agencies.

Subjects used in the study performed six training sessions over 14 days. (ANI)

Filed Under: International News Tagged With: , , , , , , , , , , , , , , , , , , ,

Cardima Appoints Dr. Peter Wong to Board of Directors

March 2, 2010 By Leave a Comment

Announces Additional Board Change
FREMONT, Calif.–(Business Wire)–
Cardima, Inc. (OTCBB: CADM) today announced the appointment of Dr. Peter Wong to
the Company`s board of directors, effective immediately. Cardima further
announced that Eric Chan, PhD, has resigned his position as a board member, also
effective immediately. Dr. Chan continues to serve as a consultant to the
Company.

Dr. Wong is a professor at the University of British Columbia, Faculty of
Medicine with a specialization in pediatric clinical neurophysiology. Dr. Wong
received his training in medicine from McMaster University and completed his
research fellowships at the University of California, San Diego and at
Children`s Hospital Medical Center, Harvard Medical School, in Boston.

“Dr. Wong has made numerous accomplishments throughout his distinguished
career,” said Tony Shum, Cardima`s Chairman. “Among these, he has developed
international collaborations and conducted collaborative clinical research with
a particular concentration in Asia. Through these collaborations he has
developed a wide range of long-lasting and valued clinical, academic and
professional contacts. We believe Dr. Wong`s experience in conducting
collaborative clinical research and his extensive relationships will
significantly benefit Cardima as we extend the scope of our clinical programs
around the world and initiate further clinical studies. We welcome Dr. Wong to
our board.”

Dr. Wong stated, “I am very excited to be joining the team at Cardima and taking
on the challenge of improving the treatment of atrial fibrillation. Cardima can
benefit from developing relationships with leading physicians and clinical
programs in Asia and globally, and I hope to contribute to this effort.”

Mr. Shum added, “On behalf of our board and our entire company, we thank Eric
Chan for his many contributions during his tenure on the Company`s board. We are
pleased that he continues to provide us his technical expertise on a consulting
basis.”

About Cardima

Cardima, Inc. has developed the PATHFINDER, TRACER and REVELATION® Series of
diagnostic catheters, the VUEPORT® and NAVIPORT® Series of guiding catheters,
the INTELLITEMP® Energy Management Device and the Surgical Ablation System. The
Surgical Ablation Probe is intended for ablation of cardiac tissue using radio
frequency (RF) energy during cardiac surgery. All of these Cardima devices have
received CE mark approval and U.S. Food and Drug Administration (FDA) 510(k)
clearance. The REVELATION Series of ablation catheters with the INTELLITEMP EP
Energy Management Device, developed for the treatment of atrial fibrillation
(AF), has received CE mark approval and is marketed in Europe.

PATHFINDER®, TRACER, VUEPORT®, NAVIPORT®, REVELATION® and INTELLITEMP® are
registered trademarks of Cardima, Inc.

Forward-Looking Statements

This press release may contain forward-looking statements. These statements are
subject to risks and uncertainties. Investors are referred to the full
discussion of risks and uncertainties associated with forward-looking statements
as contained in our reports to the Securities and Exchange Commission, including
our Forms 10-K and 10-Q. The Company assumes no obligation to update the
forward-looking information.

Cardima, Inc.
Richard Gaston MD, 510-354-0300

http://www.Cardima.com

or
Investor Contacts
Lippert/Heilshorn & Associates
Jody Cain, 310-691-7100
jcain@lhai.com

Copyright Business Wire 2010

Filed Under: International News Tagged With: , , , , , , , , , , , , , , , , , , ,

Animals give off “stench of death” to warn their living relatives about fatal diseases

September 10, 2009 By Leave a Comment

London, September 10 (ANI): Scientists have discovered that when animals die, their corpses exude a particular “stench of death” that repels their living relatives, who avoid others that have succumbed to the disease or places where predators lurk.

Corpses of animals as distantly related as insects and crustaceans all produce the same stench, caused by a blend of simple fatty acids.

This ‘death recognition system’ likely evolved over 400 million years ago.

According to a report in BBC News, the discovery was made by a team of researchers based at McMaster University, near Hamilton, Ontario, Canada.

Led by Professor David Rollo, the team stumbled upon the phenomenon while studying live cockroaches.

When a cockroach finds a good place to shelter, it gives off pheromones that attract more of its kind.

In a bid to identify the exact chemicals involved, Prof Rollo’s team extracted body juices from dead cockroaches to see what effect they had.

“We were astonished to find that nearly 100 percent of cockroaches avoid shelters treated with whole body extracts. Something in the extract was overriding any attractive chemicals,” said Prof Rollo.

“We initiated extensive work to figure out what could be so important to make all these insects go away,” he added.

After eliminating a host of other possibilities, such as cockroaches producing alarm signals, they considered the idea that a specific chemical is released by the insects upon death.By smelling their dead, cockroaches may be able to avoid predators.

The fraction that was so off-putting to other cockroaches contained nothing but simply fatty acids, with oleic and linoleic acids the two main components.

Further work by another research team showed that a very primitive type of insect called a collembola also uses these same fatty acids to recognise dead kin.

New experiments by Rollo’s team have found that terrestrial woodlice use the same chemistry to recognise their dead, using it to avoid both crushed woodlice and intact corpses.

As do two unrelated species of social caterpillar, which usually gather in large numbers.

When tested, both tent moth caterpillars and fall webworms strongly avoided extracts taken from the bodies of other dead caterpillars. They also avoided pure oleic and linoleic acids.

That means that various types of distantly-related insects, as well as woodlice, which are a type of crustacean, share a common system for recognizing death.

“Recognizing and avoiding the dead could reduce the chances of catching the disease, or allow you to get away with just enough exposure to activate your immunity,” said Prof. Rollo. (ANI)

Filed Under: Science News Tagged With: , , , , , , , , , , , , , , , , , , , ,

Gene-brain activity pattern combo behind difficult-to-hush babies

July 14, 2009 By Leave a Comment

Washington, July 14 (ANI): People finding it difficult to soothe their babies need not worry about their parenting skills anymore, for a new study suggests that children’s temperament may be due in part to a combination of a certain gene and a specific pattern of brain activity.

Writing about their findings in the journal Psychological Science, McMaster University researcher Louis Schmidt points out that the pattern of brain activity in the frontal cortex of the brain has been associated with various types of temperament in children.

He highlights the fact that infants who have more activity in the left frontal cortex are characterized as temperamentally “easy” and are easily calmed down, while those with greater activity in the right half of the frontal cortex are temperamentally “negative” and are easily distressed and more difficult to soothe.

In the current study, he and his colleagues focused on the interaction between brain activity and the DRD4 gene to see whether it predicted children’s temperament.

According to background information in the Psychological Science article, previous studies have linked the longer version of this gene to increased sensory responsiveness, risk-seeking behaviour, and attention problems in children.

In the present study, brain activity was measured in 9-month-old infants through electroencephalography (EEG) recordings. When the children were 48 months old, their mothers completed questionnaires regarding their behaviour and DNA samples were taken from the children for analysis of the DRD4 gene.

Schmidt says that the results reveal interesting relations among brain activity, behaviour, and the DRD4 gene.

He says that among the children with more activity in the left frontal cortex at 9 months, those who had the long version of the DRD4 gene were more soothable at 48 months than those who possessed the shorter version of the gene.

However, he adds, the children with the long version of the DRD4 gene, who had more activity in the right frontal cortex, were the least soothable and exhibited more attention problems compared to the other children.

Schmidt says that these findings suggest that the long version of the DRD4 gene may act as a moderator of children’s temperament.

“(The) results suggest that it is possible that the DRD4 long allele plays different roles (for better and for worse) in child temperament (depending on internal conditions or the environment inside their bodies),” note the authors.

They conclude that the pattern of brain activity-that is, greater activation in left or right frontal cortex-may influence whether this gene is a protective factor or a risk factor for soothability and attention problems.

The authors cautioned that there are likely other factors that interact with these two measures in predicting children’s temperament. (ANI)

Filed Under: Science News Tagged With: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Inkjet printer technology may be used to make toxin-detecting biosensors

July 14, 2009 By Leave a Comment

Washington, July 14 (ANI): Soon, technology that is used to make office inkjet printers may be used to develop paper-based biosensors that can detect certain harmful toxins that can cause food poisoning or be used as bioterrorism agents.

In a research, John Brennan and his research team at McMaster University, working with the Sentinel Bioactive Paper Network, describe a method for printing a toxin-detecting biosensor on paper using a FujiFilm Dimatix Materials Printer.

The researchers demonstrated the concept on the detection of acetylcholinesterase (AChE) inhibitors such as paraoxon and aflatoxin B1 on paper using a “lateral flow” sensing approach similar to that used in a home pregnancy test strip.

The process involves formulating an ink like the one found in computer printer cartridges but with special additives to make the ink biocompatible.

An ink comprised of biocompatible silica nanoparticles is first deposited on paper, followed by a second ink containing the enzyme, and the resulting bio-ink forms a thin film of enzyme that is entrapped in the silica on paper.

When the enzyme is exposed to a toxin, reporter molecules in the ink change colour in a manner that is dependent on the concentration of the toxin in the sample.

This simple and cost-effective method of adhering biochemical reagents to paper is expected to bring the concept of bioactive paper a significant step closer to commercialization.

The goal for bioactive paper is to provide a rapid, portable, disposable and inexpensive way of detecting harmful substances, including toxins, pathogens and viruses, without the need for sophisticated instrumentation.

The research showed that the printed enzyme retains full activity for at least two months when stored properly, suggesting that such sensor strips should have a good shelf life.

Portable bio-sensing papers are expected to be extremely useful in monitoring environmental and food-based toxins, as well as in remote settings in less industrialized countries where simple bioassays are essential for the first stages of detecting disease.

Applications for bioactive paper also include clinical applications in neuroscience, drug assessment, and pharmaceutical development. (ANI)

Filed Under: Science News Tagged With: , , , , , , , , , , , , , , , , , , , ,

Finding Heart-Healthy Food

April 16, 2009 By Leave a Comment

Next time finding heart healthy food for your family makes you go into a tizzy, try to relax and come to terms with the fact that there is nothing much you can do about that. Recent studies show that very few of these food products actually show strong evidence of lowering heart disease risk.

After evaluating more than 50 years of research on diet and heart disease, scientists have found that diets rich in vegetables, nuts, and those that follow a Mediterranean pattern with lots of fruits, vegetables, and fish have “strong evidence” of lowering the risk of heart disease. On the other hand starchy carbs like white bread and the trans fats in many cookies and French fries have been found to be harmful for the heart.

There are certain food products like meat, eggs and milk and many others that still have the scientists in a fix about their exact effect on the heart.

Monday’s Archives of Internal Medicine gives a complicated explanation of how the researchers rated 189 prior studies on the topic.

“I do research. I also buy groceries for my family every week,” said study co-author Dr. Sonia Anand of McMaster University in Hamilton, Ontario, who hopes the findings “decrease the confusion around what we should eat and what we shouldn’t eat.”

Filed Under: International News Tagged With: , , , , , , , , , , , , , , , , , , ,

Five-in-one combo pill for reducing heart attacks by more than 50 percent!

April 14, 2009 By Leave a Comment

According to a three-year long study conducted by researchers of the Bangalore-based St John’s Medical College, a five-in-one combo pill – Polycap – can prove beneficial in reducing the heart attack or stroke risk by as much as 50 percent, even more!

The researchers, three St. John’s doctors – Prem Pais, Denis Xavier and Alben Sigamani – and experts from Canada’s McMaster University, who were part of the global breakthrough of Polycap, said that once the wonder pill gets approved by the Drug Controller General of India, it will become available in the markets.

Manufactured by the Indian pharmaceutical company Cadila, the polypill is a combination of five drugs into one – which include three blood-pressure lowering drugs, a statin and aspirin. The findings by researchers depict that a 12-week usage of the polypill helps reduce blood pressure and cholesterol, without any increased side-effects.

Though the development and clinical testing of the pill was undertaken in Bangalore, the study was carried on in 50 centers across India, with the conclusions being based on a sample of 2,053 people aged between 45 and 80 years.

Dr Pais, St’ John’s dean elaborated on the future prospects of the research, saying: “The second phase of the study which will be commencing in 2010 would focus on the efficacy of the drug to reduce deaths, heart attacks and strokes.”

Filed Under: International News Tagged With: , , , , , , , , , , , , , , , , , , , ,

Canada’s first TB vaccine set to go under clinical trial

March 20, 2009 By Leave a Comment

Washington, Mar 20 (ANI): For the first time, researchers at McMaster University have fully designed, manufactured and tested Canada’s first tuberculosis (TB) vaccine, which is all set to go under clinical trial.

Zhou Xing, a professor in the Department of Pathology and Molecular Medicine, led development of the vaccine, currently called AdAg85A vaccine, for the landmark trial.

“The exciting thing for McMaster is that this is translational research that has gone from the basic science where the vector has been designed here at McMaster, then manufactured here, with all the pre-clinical studies done at McMaster,” said Dr. Fiona Smaill, a professor of medicine and chair of the Department of Pathology and Molecular Medicine.

While the vaccine was manufactured in the Robert E. Fitzhenry Vector Laboratory of the Institute of Molecular Medicine and Health on campus, most of the pre-clinical testing of the vaccine was undertaken at McMaster.

The phase 1 clinical trial will begin to recruit 48 healthy volunteers between 18 and 55 years of age in mid-April.

For more than 12-18 months, the researchers will evaluate the safety of the new vaccine and assess blood samples from vaccinated healthy human volunteers to determine whether the vaccine is generating a desired immune response.

A team of infectious disease physicians, vaccine manufacturing specialists, and immunologists at McMaster will conduct the trial.

The announcement of the new TB vaccine trial coincides with World TB Day on Tuesday, March 24, when health authorities and researchers around the world will be raising awareness about the need for new TB vaccines.

The researchers developed the new TB vaccine using a genetically modified adenovirus – a virus responsible for the common cold.

After removing a small portion of the gene, they inserted part of the TB gene responsible for immunity.

“It is natural ways of making the body use its own immune machinery,” said Smaill.

“Based on all pre-clinical studies carried out on animals, including mice, guinea pigs (who are very prone to TB) and cattle, this vaccine appears to be a very promising candidate vaccine,” said Xing.

Smaill said that the vaccine, manufactured to clinical grade standards at McMaster, has passed all the testing required for its use in humans. (ANI)

Filed Under: Science News Tagged With: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

How stem cells turn into blood cells

March 6, 2009 By Leave a Comment

Washington, Mar 6 (ANI): A research team led by an Indian origin scientist has shed light on how stem cells turn into blood cells.

Stem cells are the building blocks of every organ and tissue in the body. They have a unique ability to become any type of cell in the body including bone, muscle and blood cells.

Dr. Mick Bhatia, director of the McMaster University Stem Cell and Cancer Research Institute claim to have identified a particular cell pathway, known as the noncanonical Wnt that prompts stem cells to specialize and become blood cells.

The pathway appears to organize the stem cells so that they can respond to signals telling them what to turn into.

“By directing cell differentiation, this method provides the most efficient way to produce blood cells that we are aware of to date,” said Bhatia.

“This finding is exciting because it may provide a new way to make blood from human stem cells that could be used to regenerate the blood system in patients, including those with leukemia or those undergoing cancer treatments that indirectly destroy the immune and blood system,” said Dr. Christine Williams, Director of Research Programs at the Canadian Cancer Society Research Institute.

The findings are published in Cell Stem Cell. (ANI)

Filed Under: Science News Tagged With: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Fish with promiscuous females have evolved ‘super sperm’ to deal with competition

January 20, 2009 By Leave a Comment

London, January 20 (ANI): A new study led by Canadian researchers has lent more force to the belief that the evolution of ‘super sperm’ depends upon competition.

While it is known that sperm from promiscuous chimps move faster than those from relatively monogamous gorillas, Ontario-based researchers at McMaster University in Hamilton have for the first time shown the same pattern among fish too.

Research leader Sigal Balshine and her colleagues studied a variety of species of cichlid fish living in Lake Tanganyika in central Africa.

The researchers chose cichlids for the study because they form a major family of fish, with species employing the full range of mating behaviours – from monogamy to “sperm shopping”, in which a female gets several males to ejaculate into her mouth, which is where she carries her eggs.

In accordance with their promiscuity, 29 species of fish were ranked from zero to four.

The research team later recorded sperm characteristics, such as size and speed.

They corrected for the degree of relatedness between species, which might otherwise suggest a relationship between mating behaviour and sperm characteristics that did not exist, by constructing a “family tree” from cichlid mitochondrial DNA sequences.

The researchers observed that the tougher the competition among sperm, the faster, bigger, more numerous, and longer-lived they become.

According to them, sperm of strictly monogamous fish were small and slow, at around 50 microns per second.

“But as you move up the scale, species have more competitive ejaculates, with the most promiscuous producing ‘superman’ sperm – they were almost twice as fast, larger, there was more of them, and they lived longer,” New Scientist magazine quote team member John Fitzpatrick, from the University of Western Australia in Perth, as saying.

“It demonstrates for the first time that sperm traits such as speed and size can evolve together, and that those traits are related to the risk of sperm competition with rival males. Elegant,” said Mats Olsson, of the University of Wollongong in New South Wales, Australia.

The Balshine team also found that the ancestral species was monogamous, with tiny gonads, and small sperm, and that more promiscuous behaviour preceded the evolution of more competitive sperm.

A research article on the team’s study has been published in the journal Proceedings of the National Academies of Science. (ANI)

Filed Under: Uncategorized Tagged With: , , , , , , , , , , , , , , , , , , ,

Scientists identify key protein that may cause cancer cell death

January 17, 2009 By 4 Comments

Washington, January 17 (ANI): An autonomous institute of the Agency for Science, Technology and Research in Singapore has announced the discovery of a human protein called Bax-beta (Baxá), which can potentially cause the death of cancer cells and lead to new approaches in cancer treatment.

“Our research findings reveal that Baxá protein levels are normally kept at essentially undetectable levels in healthy cells by the protein degradation machine in cells known as proteasomes,” said Dr. Victor Yu, who led the Institute of Molecular and Cell Biology (IMCB) research team.

In a researcher article in the journal Molecular Cell, the researchers describe proteasomes as “protein-digesting machines” that regulate cellular levels of various proteins, including that of the lethal Baxá, by breaking them into smaller components within the cell.

“Thus, the proteasomes are there to keep the lethal Baxá in check. This is exciting – if the proteasome-mediated degradation of Baxá could be inhibited specifically in cancer cells, it could cause the harmful cancer cells to go through apoptosis,” Dr. Victor Yu said.

In apoptosis, unwanted, damaged and infected cells are eliminated.

Before the discovery of Baxá, only one single protein called Bax-alpha (Baxa) had been extensively studied in cells.

The researchers have now found that Baxá is able to associate with, and promote, Baxa activation, and that Baxá, in its native form, is 100 times more potent than its sibling Baxa in triggering a key step in apoptosis.

They believe that the development of such compounds as can elevate levels of Baxá, or stimulate its interaction with Baxa, may pave the way for new drug approaches to cancer treatment, as these compounds are likely to enhance the apoptotic signals triggered by many conventional cancer drugs, which frequently cause toxic side effects in patients when higher doses of drugs are needed.

Dr. David Andrews, Professor of Biochemistry and Biomedical Sciences at McMaster University, Canada said: “The beta-isoform4 of Bax has been enigmatic for several years. Although earlier research had hinted at its existence, the protein has proven extremely difficult to detect or examine functionally. Even attempts to produce the protein in the laboratory have been largely unsuccessful. In this study the Yu group resolves these issues by demonstrating that in cells Baxá is normally rapidly degraded and kept at low levels, and when it is not degraded, it is profoundly apoptotic on its own and works in concert with Baxa. These studies provide information necessary for the elucidation of the importance of Baxá in cell physiology.” (ANI)

Filed Under: Health News Tagged With: , , , , , , , , , , , , , , , , , , ,

Stars become overweight due to ‘stellar cannibalism’

January 15, 2009 By Leave a Comment

London, Jan 15 (ANI): In a new research, scientists have discovered that the mysterious overweight stars known as blue stragglers are the result of ‘stellar cannibalism’ where plasma is gradually pulled from one star to another to form a massive, unusually hot star that appears younger than it is.

The research was part funded by the UK’s Science and Technology Facilities Council (STFC) and carried out by scientists at Southampton University and the McMaster University in Canada.

Blue stragglers are found throughout the Universe in globular clusters – collections of about 100, 000 stars, tightly bound by gravity.

According to conventional theories, the massive blue stragglers found in these clusters should have died long ago because all stars in a cluster are born at the same time and should therefore be at a similar phase.

These massive rogue stars, however, appear to be much younger than the other stars and are found in virtually every observed cluster.

“The origin of blue stragglers has been a long-standing mystery. The only thing that was clear is that at least two stars must be involved in the creation of every single blue straggler, because isolated stars this massive simply should not exist in these clusters,” said Dr Christian Knigge from Southampton University, who led the study.

“We’ve known of these stellar anomalies for 55 years now. Over time, two main theories have emerged: that blue stragglers were created through collisions with other stars; or that one star in a binary system was ‘reborn’ by pulling matter off its companion,” said Professor Alison Sills from the McMaster University.

The researchers looked at blue stragglers in 56 globular clusters.

They found that the total number of blue stragglers in a given cluster did not correlate with predicted collision rate – dispelling the theory that blue stragglers are created through collisions with other stars.

They did, however, discover a connection between the total mass contained in the core of the globular cluster and the number of blue stragglers observed within in.

Since more massive cores also contain more binary stars, they were able to infer a relationship between blue stragglers and binaries in globular clusters.

They also showed that this conclusion is supported by preliminary observations that directly measured the abundance of binary stars in cluster cores.

All of this points to “stellar cannibalism” as the primary mechanism for blue straggler formation.

According to Dr Knigge, “This is the strongest and most direct evidence to date that most blue stragglers, even those found in the cluster cores, are the offspring of two binary stars.” (ANI)

Filed Under: Educational News Tagged With: , , , , , , , , , , , , , , , , , , ,