China Is Genetically Engineering Mini Pigs To Sell As Pets


We’d all like our baby pets to stay perpetually tiny, but scientists in China are taking that desire to a whole new level.

BGI, a genomics institute located in Shenzhen, announced in late September that it is genetically engineering miniature pigs to sell as pets for $1,600 each.

<span class='image-component__caption' itemprop="caption">BGI's genetically engineered pigs are not to be confused with teacup pigs (pictured above, on the right), which, according to The Dodo, are <a href="https://www.thedodo.com/whats-misleading-about-the-tea-843842300.html">actually stunted potbellied pigs</a>.</span>
Genetically engineered pigs are not to be confused with teacup pigs (pictured above, on the right), which, according to The Dodo, are actually stunted potbellied pigs.

The institute creates the micropigs by using a gene-editing technique that alters the genomes of a Bama — an already small breed of pig — to make it even smaller. BGI uses TALENs (an enzyme) to disable one of two copies of the growth hormone receptor gene in a Bama’s fetal cells.

BGI then clones pigs from the fetus, which produces stunted male Bama clones that are, in turn, naturally bred with normal females. Half of the resulting offspring are micropigs.

Unlike normal Bamas — which can weigh up to 100 pounds — these lab-created pigs only grow up to 30 pounds when mature, around the same weight as a medium-sized dog.

The micropigs were originally used as lab animals that acted as models for human disease, according to Nature magazine. Pigs, specifically smaller breeds of pig, are commonly used as model organisms in biomedical research because they “closely [resemble] man in anatomy, physiology and genetics,” according to the National Center for Biotechnology Information.

<span class='image-component__caption' itemprop="caption">In 2005, the University of Georgia in Athens, Georgia, and ProLinia Inc. <a href="http://www.cabi.org/agbiotechnet/news/1475">produced healthy cloned piglets</a> (shown above) from the skin cells of a commercial hog.</span>ERIK S. LESSER VIA GETTY IMAGESIn 2005, the University of Georgia in Athens, Georgia, and ProLinia Inc. produced healthy cloned piglets (shown above) from the skin cells of a commercial hog.

According to Yong Li, technical director of BGI’s animal-science platform, BGI has not observed any health problems associated with cloning in any of the gene-edited pigs they’ve produced.

In the future, the institute promises to offer miniature pigs in a variety of coat colors and patterns, which will be achieved through further gene editing.

While BGI feels confident about bringing genetically modified micropigs to the public, other experts remain skeptical.

“Obviously, this has to be regulated,” Yusuff Abdu, a researcher at New York University’s School of Medicine, told Inverse.com. “You can’t let lab-engineered animals out into the public. There is a high chance they could get into the wild and offset an ecosystem if they happen to have an advantageous trait. Lab rats and mice are kept out of pet stores for this reason.”

For its part, BGI says that the profits made from selling the micropigs as pets will be invested in research that explores how gene editing in pets and in medical research can be regulated.

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Buddhist plants daisies to absorb Fukushima radiation


World’s largest atom smashers produce world’s smallest droplets: How small can a droplet shrink and still remain a liquid?


A series of experiments has created the tiniest drops of quark-gluon plasma ever made, scientists report.

This is a aiagram of a proton-lead collision in the Large Hadron Collider that produced a drop of quark-gluon plasma about one-tenth the size of those produced in previous experiments.

How small can a droplet shrink and remain a liquid?

This existential question has been raised by a series of experiments conducted recently at the Large Hadron Collider and the Relativistic Heavy Ion Collider that smash various atomic particles together at nearly the speed of light in order to create tiny drops of primordial soup: the quark-gluon plasma (QGP) that cosmologists are convinced dominated the universe microseconds after the Big Bang before the universe cooled down enough for atoms to form. In fact, the flow characteristic of these droplets is a major topic at a scientific conference, Quark Matter 2015, taking place this week in Kobe, Japan.

As part of the Large Hadron Collider’s CMS detector team, Professor of Physics Julia Velkovska, post-doctoral fellow Shenguan Tuo and assistant research professor Shengli Huang at Vanderbilt University have been at the middle of these discoveries.

In 2010, the LHC successfully created sub-atomic blobs of QGP by colliding lead ions together. Smashing these two massive ions — each containing hundreds of protons and neutrons — had generated the tremendous temperatures, more than 250,000 times hotter than the core of the sun, that are required for the primordial state of matter to form.

(Unfortunately, the physicists don’t have a direct way to measure the number of particles in the quark-gluon plasma, so they use the number of subatomic particles that are created when the plasma evaporates as a measure of their size.)

“Lead ions are very large, each containing hundreds of protons and neutrons. When you smash them together at very high speed, they generate blobs of plasma that produce thousands of particles when they cool down,” said Velkovska. “But when the LHC switched to proton-lead ion collisions, we didn’t think the collisions would contain enough energy to produce the plasma.”

However, Tuo, as part of his doctoral thesis, made detailed measurements of the behavior of the particles produced by these smaller proton-lead collisions and discovered that they were in fact producing liquid droplets that were about one tenth the size of those produced in the lead-lead collisions.

“Everyone was surprised when we began finding evidence for liquid behavior,” said Tuo. “It caused some very intense debates.”

One of the key properties of a liquid is the ability to flow. Looked at from the point of view of the individual particles in a liquid, the ability to flow means that each particle is exerting an attractive force on its neighbors that is strong enough to effect their movement but not strong enough to lock them together like they are in a solid. So their movements are coordinated and, when released from a container, they retain information about the container’s shape. Tuo’s measurements showed that small numbers of particles produced in the proton-lead collisions originated on the ellipsoidal surfaces of small QGP droplets.

Because of the computational difficulty involved, physicists normally look for these correlations between pairs of particles, but Velkovska, Tuo and their CMS collaborators took it several steps further. They searched for correlations between groups of four, six and eight particles. In some cases, they went to the extraordinary length of computing the correlations between all the particles in a given collision.

“These measurements confirmed that we were seeing this coherent behavior even in droplets producing as few as 100 to 200 particles,” Tuo said. The results were published in Physical Review Letters in June. But that wasn’t the end of the story.

The recreation of the quark gluon plasma (QGP) dates back to 2005. Velkovska and her Vanderbilt colleagues — physics professors Victoria Greene and Charlie Maguire — were members of the PHENIX science team at RHIC, located at Brookhaven National Laboratory, when they announced that they had created this new state of matter by colliding gold ions together at relativistic velocities. The big surprise was that this primordial material behaved like a liquid, rather than a gas.

To see what happened at even higher energies, the Vanderbilt group joined the CMS science team at the LHC located at the European Laboratory for Nuclear and Particle Physics in Geneva. The more powerful particle collider succeeded in duplicating the RHIC results, first as expected, by smashing lead ions together and then, unexpectedly, in the proton-lead collisions.

The proton-lead results prompted the scientists in the PHENIX team to re-analyze data that had been collected at RHIC in 2000, when the collider had smashed deuterium ions (proton-neutron pairs) and gold ions together at much lower energies than those in the LHC. The re-analysis, led by Shengli Huang, found that the proton-neutron pairs formed two hot spots in the gold ion when they collided which then merged into an elongated drop of QGP.

The RHIC researchers decided to test this further by adding a new run that collided helium ions (two protons and a neutron) with gold ions, and found that the same thing happened, except that three hot spots formed and merged into the QGP droplet. The results were just published in Physical Review Letters.

“Although the LHC collisions release 25 times more energy than the RHIC collisions, we don’t see much difference in the droplet-formation process: Once you have reached the threshold, adding more energy doesn’t seem to have much effect,” said Velkovska. “I guess you can’t get more perfect than perfect!”

Not only have the physicists found that the quark-gluon plasma is a liquid, the physicists have also established that it is nearly a perfect liquid: That is a liquid with zero viscosity that flows without any resistance. If you swish a perfect liquid in a glass and set the glass down, then the liquid will continue to swirl around as long as it is not disrupted.

Curiously, the phenomenon that most closely resembles the properties of the hottest known liquid is one of the coldest known liquids: lithium atoms that have been cooled to temperatures one-billionth of a degree above absolute zero using a device called a laser trap. When released from the trap these ultra-cold atoms also behave as a perfect liquid with near-zero viscosity.

“These are both strongly coupled systems. This appears to be an emergent property of such systems,” Velkovska has concluded.

Sleep may strengthen long-term memories in the immune system


More than a century ago, scientists demonstrated that sleep supports the retention of memories of facts and events. Later studies have shown that slow-wave sleep, often referred to as deep sleep, is important for transforming fragile, recently formed memories into stable, long-term memories. Now, in an Opinion article published September 29 in Trends in Neurosciences, part of a special issue on Neuroimmunology, researchers propose that deep sleep may also strengthen immunological memories of previously encountered pathogens.

“While it has been known for a long time that sleep supports long-term formation in the psychological domain, the idea that long-term is a function of sleep effective in all organismic systems is in our view entirely new,” says senior author Jan Born of the University of Tuebingen. “We consider our approach toward a unifying concept of biological long-term memory formation, in which sleep plays a critical role, a new development in and memory research.”

The immune system “remembers” an encounter with a bacteria or virus by collecting fragments from the bug to create memory T , which last for months or years and help the body recognize a previous infection and quickly respond. These memory T cells appear to abstract “gist information” about the pathogens, as only T cells that store information about the tiniest fragments ever elicit a response. The selection of gist information allows memory T cells to detect new pathogens that are similar, but not identical, to previously encountered bacteria or viruses.

Studies in humans have shown that long-term increases in memory T cells are associated with deep slow-wave sleep on the nights after vaccination. Taken together, the findings support the view that slow-wave sleep contributes to the formation of long-term memories of abstract, generalized information, which leads to adaptive behavioral and immunological responses. The obvious implication is that could put your body at risk.

“If we didn’t sleep, then the immune system might focus on the wrong parts of the pathogen,” Born says. “For example, many viruses can easily mutate some parts of their proteins to escape from immune responses. If too few antigen-recognizing cells [the cells that present the fragments to T cells] are available, then they might all be needed to fight off the pathogen. In addition to this, there is evidence that the hormones released during sleep benefit the crosstalk between antigen-presenting and antigen-recognizing cells, and some of these important hormones could be lacking without sleep.”

Born says that future research should examine what information is selected during for storage in long-term memory, and how this selection is achieved. In the end, this research could have important clinical implications.

“In order to design effective vaccines against HIV, malaria, and tuberculosis, which are based on immunological memory, the correct memory model must be available,” Born says. “It is our hope that by comparing the concepts of neuronal and immunological memory, a model of can be developed which integrates the available experimental data and serves as a helpful basis for vaccine development.”

An Update on Peritoneal Dialysis


Peritoneal dialysis (PD) is the main form of renal replacement therapy (RRT) performed in the home environment.  The number of patients treated with PD in the United States continues to rise as a result of multiple factors, including economic incentives and improved patient and provider education. The outcomes on PD were recently explored in anarticle in AJKD.

When evaluating the two PD modalities, survival amongst CAPD (continuous ambulatory PD) versus APD (automated PD) is similar. It remains uncertain if a survival advantage exists between PD versus in-center hemodialysis (iHD). Access type does indeed impact mortality as shown by a Canadian study of over 38,000 patients initiating dialysis. The study demonstrated that the risk of death was 20% higher in patients who started HD with a central venous catheter (CVC), compared to the PD group in the first five years of dialysis. In addition, those starting HD with an AV access had similar survival to the PD group.

Congestive heart failure with preserved ejection fraction is a common co-morbidity among PD patients, and has been noted to lead to poor outcomes. Diabetic patients on CAPD are noted to have worse survival and technique success than their age matched non-diabetic controls. The role of residual renal function (RRF) continues to be of importance with respect to survival. The use of ACE inhibitors or ARBs has been shown to preserve this function.

Multiple PD catheter options exist, and to date, no one catheter design has proven to be superior. Although numerous PD catheter insertion techniques exist, it is important to note that laparoscopic placement is associated with longer operative times, higher costs, and the need for general anesthesia, but can proactively address problems that may adversely affect catheter outcomes.  The laparoscopic approach is associated excellent long term outcomes. The role of an embedded PD catheter should also be considered as it may allow for an urgent initiation of RRT while avoiding a CVC.

Conventional PD solutions use dextrose as the osmotic agent with 3 main concentrations: 1.5%, 2.5%, and 4.25%. These solutions have been associated with both local and systemic toxicities, which are a result of exposure to the low pH, lactate buffer, hyperosmolality, glucose as the osmotic agent, and glucose degradation product (GDP) levels. The main glucose-sparing agent used in PD is icodextran, which has been associated with improved glycemic control, glucose-induced lipid abnormalities, and ultrafiltration.

The concept of PD adequacy has multiple components. Factors such as nutrition, anemia management, mineral and bone disorders, and acid-base balance are critical. Total solute clearance as expressed by weekly Kt/Vurea is the main clinical factor used to assess adequacy. A delivered weekly clearance should be a minimum Kt/Vurea of 1.7, combining both peritoneal and renal clearances.

Adequacy can be achieved using three modalities of PD. CAPD, continuous cyclic peritoneal dialysis (CCPD), and nocturnal intermittent peritoneal dialysis (NIPD). Adjustments to the prescription can be based on achieved adequacy and the peritoneal equilibration test (PET).

In addition to adequacy, maintaining euvolemia is essential in PD. This can be achieved by PD prescription alterations, maintaining sodium restriction guidelines, preserving RRF (ACEi/ARB therapy, avoiding nephrotoxins/hypovolemia/peritonitis), and the use of diuretics. In line with these maneuvers, understanding the role of transport characteristics and PD prescription management is key.

Infectious complications of PD can be devastating, and are associated with significant morbidity and mortality. 15-18% of patients treated with PD die as a result of peritonitis. One of the key strategies used to reduce the rate of peritonitis is prevention of exit site infections. This can be achieved via exit site care and topical gentamicin applied to the exit site. Empiric treatment should exit site infections occur should include a penicillinase-resistant or first generation cephalosporin.

Patients presenting with cloudy effluent should be presumed to have peritonitis. This is confirmed by a cell count and culture of the peritoneal fluid. An effluent white blood cell count of 100 per microliter after a 2 hour dwell with at least 50% neutrophils indicates inflammation, with peritonitis as the most likely cause. Empiric treatment to cover both gram-negative and gram-positive organisms should be initiated until final culture results are reported. It is important to note that the most frequent cause of peritonitis is gram-positive in origin. Intraperitoneal administration is recommended unless the patient is hospitalized and acutely ill, in which case IV antibiotics may be appropriate.

The three major non-infectious complications related to PD include peritoneal membrane changes, ultrafiltration failure (UFF), and encapsulating peritoneal sclerosis (EPS). Long-term use of PD may result in morphological changes. There are three types of membrane failures with Type 1 (high transporter) being the most common followed by Type 3 (aquaporin deficit and excessive lymphatic reabsorption). Type 2 (low transporter) membrane failure is the least common. EPS continues to be a devastating complication of PD, carrying a significant morbidity and mortality. The management of EPS can be supportive (nutritional), medical, or surgical.

Both urgent start PD and PD for AKI initiatives offer alternatives to the current treatment paradigms. In both cases the avoidance of vascular access and the complications associated with this may lead to possible overall better patient outcomes.

Gut bacteria population, diversity linked to anorexia nervosa: Studying the ‘gut-brain axis,’ researchers find evidence of an association.


Studying the ‘gut-brain axis,’ researchers find evidence of an association between the gut microbiota and the eating disorder anorexia nervosa.

Results of this study provide more evidence that the abundance and diversity of the gut microbiota — the trillions of bacteria that affect digestive health and immunity — could also affect the so-called “gut-brain axis.”

Researchers at the UNC School of Medicine found that people with anorexia nervosa have very different microbial communities residing inside their guts compared to healthy individuals and that this bacterial imbalance is associated with some of the psychological symptoms related to the eating disorder.

The findings, published in the journal Psychosomatic Medicine, provide more evidence that the abundance and diversity of the gut microbiota — the trillions of bacteria that affect digestive health and immunity — could also affect the so-called “gut-brain axis.” This research suggests that gut bacteria could play a prominent role in the debilitating symptoms of anorexia nervosa, a serious eating disorder that affects more than 3 million Americans and has the highest mortality rate of any psychological disorder.

“Other studies have linked gut bacteria to weight regulation and behavior,” said Ian Carroll, PhD, senior author of the paper and assistant professor of medicine in the UNC Center for Gastrointestinal Biology and Disease. “Since people with anorexia nervosa exhibit extreme weight dysregulation, we decided to study this relationship further.”

Carroll added, “We’re not able to say a gut bacterial imbalance causes the symptoms of anorexia nervosa, including associated symptoms, such as anxiety and depression. But the severe limitation of nutritional intake at the center of anorexia nervosa could change the composition of the gut microbial community. These changes could contribute to the anxiety, depression, and further weight loss of people with the disorder. It’s a vicious cycle, and we want to see if we can help patients avoid or reverse that phenomenon. We want to know if altering their gut microbiota could help them with weight maintenance and mood stabilization over time.”

For this study, Carroll’s team collected fecal samples from 16 women with anorexia nervosa after they were first admitted into the UNC Center of Excellence for Eating Disorders and then again after their weight was restored — when they were discharged from UNC. Then Susan Kleiman, a graduate student in Carroll’s lab and first author of the paper, characterized the composition and diversity of the gut microbiota in each sample.

Kleiman found significant changes in the gut bacteria populations between admission and discharge. The samples taken at clinic admission had fewer different types of bacteria, making the intestinal communities much less diverse. Microbial diversity is a sign of better overall health. Upon hospital discharge, the microbial diversity had increased, but was still significantly less diverse than that of 12 healthy individuals, whose gut microbiotas were analyzed for this study.

As the microbial communities in patients with anorexia improved during clinical care and weight gain, the moods of patients also improved. Thus, the researchers noted an association between the gut microbiota and a central symptom of people with anorexia nervosa.

The question remains whether improving microbial abundance and diversity could help relieve symptoms related to the eating disorder. To find out, Carroll formed a team of researchers including Cynthia Bulik, PhD, director of the UNC Center of Excellence for Eating Disorders; John Cryan, PhD, professor at University College Cork; Lisa Tarantino, PhD, assistant professor of psychiatry at UNC-Chapel Hill; Anthony Fodor, PhD, a bioinformatics expert at UNC-Charlotte, and Hunna Watson, PhD, a psychologist and biostatistician at UNC-Chapel Hill.

This month, they received a five-year, $2.5-million grant from the National Institutes of Mental Health to further study the relationship between the gut microbiota and anorexia nervosa.

“Over the past 10 years, prominent researchers have learned that when you take gut microbial communities of an obese person and put it in germ-free mice — which are maintained in sterile conditions and lack intestinal microbiota — the mice gain more weight than germ-free mice that have been colonized with a gut microbiota from a lean individual,” Carroll said. “This suggests that gut microbes mediate weight gain or loss.”

Other animal studies showed that adding gut bacteria to previously germ-free mice altered their behavior, especially in relation to anxiety and stress.

“We’re not saying that altering gut bacteria will be the magic bullet for people with anorexia nervosa,” Carroll said. “Other important factors are at play, obviously. But the gut microbiota is clearly important for a variety of health and brain-related issues in humans. And it could be important for people with anorexia nervosa.”

As part of the new NIH grant, his team will characterize the microbiotas of a large number of people with anorexia nervosa as they enter UNC’s clinic and when they are discharged, which typically happens when they reach about 85 percent of their ideal body weight. Then his team will put those gut bacteria in germ-free mice. This will help Carroll learn how the microbiota from anorexia nervosa patients affects the biology and behavior of the mice.

If Carroll’s team learns that the bacteria has a detrimental effect on the mice, then this might suggest that cultivating a healthy microbiota could serve as a therapeutic route to help people with anorexia nervosa.

“Currently available treatments for anorexia nervosa are suboptimal,” Bulik said. “In addition, the process of weight gain and renourishment can be extremely uncomfortable for patients. Often, patients are discharged from the hospital, and within months and sometimes weeks they find themselves losing weight again and facing readmission. If specific alterations in their microbiota could make renourishment less uncomfortable, help patients regulate their weight, and positively affect behavior, then we might see fewer readmissions and more cures.”

Know how to eat correctly according to your blood type


People do most of the things to keep themselves healthy. They exercise, do yoga, take stairs and eat healthy food. Include fruits, vegetables in their diet; avoid meats and other harmful foods. But even after doing so much to keep yourself healthy you find yourself lethargic, battle digestion problems you need to think for some unorthodox diet. Have you thought of eating according to your blood type?

Dr. Peter D’Adamo says that eating according to your blood type is beneficial to your health and can help you live longer and healthier. There are chemical reactions occurring in our blood because of the food we eat. These reactions are generally dependent on genetic heredity since they are caused by the proteins found in foods, which have a capacity to do blood stations and to stick around proteins.

So here are the types of food which you should eat according to your blood types.

1Type O

People with blood type O are generally focused, energetic and display tremendous leadership qualities. Such people crave for meat and have characteristics of hunters- gatherers.

People with Type O blood group should eat a diet consisting of protein rich meal like lean meat, poultry, fish and vegetables. Beans, grains and dairy should be eaten lightly in their day to day meals. If you want to lose weight try eating seafood, red meat, spinach and broccoli. Avoid wheat, corn, lentils and cabbage. Try eating salt to lower the levels of Iodine in your system to give you optimal thyroid function.

Type O

Type A

People with Type A blood group tend to have poor digestion systems and an aversion to food coming from animals. People from this group favour vegetarian food like legumes, grains, fruits and vegetables.

Try eating soybeans, vegetables, pineapple to lose weight and avoid meat, dairy products, bean and wheat. Type A people are generally responsible, cool minded, hardworking and detail oriented. But crave for success, are constantly worried about perfection.

Fish and poultry should be limited since people with blood type A produce fewer meat-digesting enzymes, which is why they have such a hard time digesting red meat. Try including higher percentage of wheat; grains, cereals etc should be your staple diet.

Type A

Type B

People with Type B blood are stubborn in nature. They love working in jobs that they like and they always follow their own rules. Therefore you are not as cooperative as other would like.

Type B people can very well digest meat products with ease. Hence most of your meals should contain red meat (beef, venison and lamb). Also try and include dairy products like yogurt, cheese and milk in your diet. Leafy greens and vegetables, fruits like banana, grapes, plum etc should also benefit people with type A blood.

Try to avoid grains, corn, rye and wheat and nuts like peanuts, sunflower seeds and sesame seeds as they tend to change the way you metabolize food.

Type B

Type AB

Type AB is the newest blood type and rarest. They also share traits with type A and Type B and hence have much more to choose form in order of what they can eat.

Personality wise people with Type AB are trusty, difficult to read and volatile. These people help out others a lot, but on their own conditions. They can digest meats like Type B but also tend to store it as fat thanks to low metabolism, a trait they share with type A. Type AB people should eat vegetable rich food. Include tofu, dairy products, and fruits like cherries, watermelon and figs in their diet. Also eat easily digested food such as seafood like snapper, salmon, tuna etc.

Type AB

Avoid meats like beef, pork, and shellfish since it would be difficult to digest for you. Also moderate the use of caffeine and alcohol that you consume.

Handle With Care: The Human Brain Is Delicate And You Should Take Care Of It


humanbrain

Your brain is softer than most of the meat you’d find in a grocery store. So treat it nicely. University of Utah Brain Institute, YouTube/screenshot

It’s easy to see a 3-year-old run himself into his bedroom wall, shake it off, and go play in another room, and think the brain is indestructible. Or maybe you see hulking grown men hurling themselves at one another on the football field and chalk up their lasting health to their athleticism. But one neurobiology professor would like to disagree.

Dr. Suzanne Stensaas, of the University of Utah School of Medicine, has a freshly autopsied brain that she’d like you to take a look at. Stensaas also teaches anatomy, which means she can name just about every nook and cranny of the brain’s myriad folds and pathways. As she turns over the three-pound mass in her hands, she reflects on how soft it really is. Not even a minute of it resting in her hands and one finger already leaves a dent in the tissue.

“Think how vulnerable the brain is, and then think how narrow and small the spinal cord is and how devastating a quick subluxation of the vertebra, or a herniation of a disk,” would be to the delicate spinal cord, Stensass explains. “It’s much softer than most of the meat you would see in a market.”

Should it be any wonder that concussions and other traumatic brain injuries are so common in high-impact sports? Cerebrospinal fluid acts as a protective cushion around the brain, but nothing can stop the organ from bashing into the inner walls of the skull after quickly stopping at a high velocity — no matter how advanced a helmet (or 3-year-old sense of limitlessness) may be.

Researchers find a new way to weigh a star


pulsar
An artist’s impression of a pulsar with its surrounding magnetic fields (blue lines). 

Researchers from the University of Southampton have developed a new method for measuring the mass of pulsars – highly magnetised rotating neutron stars formed from the remains of massive stars after they explode into supernovae.

Until now, scientists have determined the mass of stars, planets and moons by studying their motion in relation to others nearby, using the gravitational pull between the two as the basis for their calculations. However, in the case of young pulsars, mathematicians at Southampton have now found a new way to measure their mass, even if a star exists on its own in space.

Dr Wynn Ho, of Mathematical Sciences at the University of Southampton, who led the research says: “For pulsars, we have been able to use principles of nuclear physics, rather than gravity, to work out what their mass is – an exciting breakthrough which has the potential to revolutionise the way we make this kind of calculation.”

Collaborator Dr Cristobal Espinoza of the Pontificia Universidad Catolica de Chile goes on to explain: “All previous precise measurements of masses have been made for stars that orbit another object, using the same techniques that were used to measure the mass of the Earth or Moon, or discover the first extrasolar planets. Our technique is very different and can be used for pulsars in isolation.”

Pulsars emit a rotating beam of electromagnetic radiation, which can be detected by telescopes when the beam sweeps past the Earth, like observing the beam of a lighthouse. They are renowned for their incredibly stable rate of rotation, but young pulsars occasionally experience so-called ‘glitches’, where they are found to speed up for a very brief period of time.

The prevailing theory is that these glitches arise as a rapidly spinning superfluid within the star transfers its rotational energy to the star’s crust, the component that is tracked by observations.

Professor of Applied Mathematics at Southampton, Nils Andersson explains, “Imagine the pulsar as a bowl of soup, with the bowl spinning at one speed and the soup spinning faster. Friction between the inside of the bowl and its contents, the soup, will cause the bowl to speed up. The more soup there is, the faster the bowl will be made to rotate.”

Dr Ho has collaborated with his colleague Professor Andersson and external researchers Dr Espinoza and Dr Danai Antonopoulou of the University of Amsterdam, to use new radio and X-ray data to develop a novel mathematical model that can be used to measure the mass of pulsars that glitch. The idea relies on a detailed understanding of superfluidity. The magnitude and frequency of the pulsar glitches depend on the amount of superfluid in the star and the mobility of the superfluid vortices within. By combining observational information with the involved , one can determine the of the star.

The team’s results have important implications for the next generation of radio telescopes being developed by large international collaborations, like the Square Kilometre Array (SKA) and the Low Frequency Array (LOFAR), of which Southampton is a UK partner university. The discovery and monitoring of many more pulsars is one of the key scientific goals of these projects.

“Our results provide an exciting new link between the study of distant astronomical objects and laboratory work in both high-energy and low-temperature physics. It is a great example of interdisciplinary science,” says Professor Andersson.

New Antibiotic-Resistant ‘Superbug’ an Emerging Threat, CDC Says .


A relatively new antibiotic-resistant bacteria called CRE is making inroads in some major American cities, U.S. health officials report.

Surveillance of seven U.S. metropolitan areas found higher-than-expected levels of CRE in Atlanta, Baltimore and New York City, according to the U.S. Centers for Disease Control and Prevention.

Lower-than-expected levels were found in Albuquerque, Denver and Portland, Ore., while the Minneapolis rate was what the agency anticipated.

But CDC researchers were dismayed that they found active cases of CRE infection in every city they examined, said senior author Dr. Alexander Kallen, a CDC medical officer.

The results support the CDC’s decision to promote coordinated regional efforts to prevent the spread of CRE and other antibiotic-resistant germs, Kallen said.

“Here we are with an opportunity to intervene on one of these multidrug-resistant organisms just as it’s about to emerge and it’s still relatively uncommon,” he said. “That is the time you want to intervene. It’s much easier to control things and prevent the organism from becoming more common when it’s rare.”

About 9 percent of people died due to their infection from CRE, the researchers found. But some estimates have held that as many as 50 percent of CRE infections contribute to death if they lead to a bloodstream infection, Kallen said.

CRE, or Carbapenem-resistant Enterobacteriaceae, are a class of common bacteria that have developed resistance to some of the most widely used antibiotics, Kallen said. CRE were first reported in 2001.

The best-known enterobacteriaceae are E. coli, a common cause of food poisoning, and Klebsiella pneumoniae, which can cause pneumonia and potentially fatal bloodstream infections, Kallen said.

CRE bacteria are able to produce an enzyme that breaks down antibiotics, forcing doctors to resort to older and more toxic antibiotics to stave off infections, he said.

Most CRE infections occur at a hospital. In fact, hospitalization was the most common potential exposure to CRE, the study found. Patients’ median (midpoint) age was 66.

But public health experts are worried that since enterobacteriaceae are so common in daily life, havoc could ensue if CRE starts to become transmitted outside of health care settings.

“We’re seeing more and more patients in the community with an e. coli kidney infection that we have no oral therapy to treat,” said Dr. Mary Hayden, an associate professor of pathology at Rush University Medical Center in Chicago. “If CRE gets into the community and starts causing regular old urinary tract infections in otherwise healthy people, it will have a significant impact because we don’t have agents to treat those things.”

In the study, published Oct. 5 in the Journal of the American Medical Association, the CDC conducted active surveillance of CRE in 2012 and 2013 among people living in the seven cities listed above.

The overall rate of CRE in those cities was 2.93 infections per 100,000 people, researchers found.

That’s low compared with the antibiotic-resistant bug MRSA, and the opportunistic C. difficile bacteria, which causes potentially deadly diarrhea in people whose digestive systems have been subjected to heavy antibiotics.

However, CRE has become more common in a short amount of time, said Hayden, who wrote an accompanying editorial in the journal.

“I think we learned from those situations that these problems can spread very rapidly,” she said. “If we look at what has happened with other similar antibiotic-resistant organisms, we can see what will happen with this unless we do something now.”

To stop the spread of antibiotic-resistant bacteria, the CDC is promoting regional efforts in which hospitals, long-term care facilities and other health care offices communicate regularly about infections, Kallen said.

Many antibiotic-resistant bacteria spread in a community because they are carried by patients from one facility to another. Better coordination can prevent this spread by identifying patients and isolating them with good infection control, he said.

Hayden praised this study as a “really good initial step,” but said she hopes it will be expanded to include many other metropolitan areas.

“This provides a nice national picture, but we could do better,” she said.

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