ScienceDaily (June 28, 2012) A study with extant mammals refutes the hypothesis on which the assumption that dinosaurs were ectotherms was based.

The work was carried out by researchers from Institut Catal de Paleontologia (ICP) and Universitat Autnoma de Barcelona (UAB). It has been published in Nature.

The study analysing the lines of arrested growth (LAG) in the bones of around a hundred ruminants, representative of the specific and ecological diversity of that group of mammals. The results show that the presence of these lines is not an indicator of an ectothermic physiology (does not generate internal heat), as had previously been thought, since all warm-blooded mammals have them. The study therefore dismantles the key argument of the hypothesis that dinosaurs could have been cold-blooded reptiles.

The work was carried out by Meike Khler, ICREA researcher and ICP palaeontologist; Ronny Aanes, researcher from the Norwegian Polar Institute; Nekane Marn, PhD student at the UAB and Xavier Jordana, lecturer of postgraduate studies at same university.

LAGs are seen in bone sections as dark rings, similar to those seen in tree trunks. The rings are formed, both in the studied mammals and in trees, during the unfavourable seasons (winter or dry season) when the growth of the organism is arrested as a result of a lack of resources. The presence of LAGs in bones was, until now, considered to be the clearest indicator of ectothermy since the seasonal arrest of growth was related to the animal's inability to maintain a more or less constant body temperature (endothermy) during the season of scarce resources.

Meike Khler explains: "the study we have carried out is very powerful, both in terms of the amount of material and the diversity of species with which we worked, but we did not design it to find a response to the thermophysiology of dinosaurs. We sought to better understand the physiology of extant mammals and how the environment affects them -- how their growth changes as a result of external temperatures, rain and the availability of food and water."

Understanding this was the first step to establishing discussions in paleontological research about the physiology of animals that lived several million years ago.

But the researchers realised that what they observed in the bones of different ruminants refutes the main argument for an ectothermic physiology in dinosaurs. Many hypotheses set out from the premise that large mammals -- endothermic par excellence -- do not have LAGs in their hard tissues since they do not need to arrest their growth responding to external temperature conditions. In fact, since LAGs have been observed in almost all species of dinosaur, many scientists considered that they were cold-blooded reptiles.

The article published in Nature offers the first systematic study, based on an extensive sample of mammals representative of a large variety of ecosystems, which shows that LAGs do not indicate an ectothermic physiology but give us information about how the physiology (metabolism) of an animal changes according to seasonal endocrinal changes, both in cold- and warm-blooded animals. These changes represent a common heritage in all vertebrates and are a kind of internal clock that regulates the animals' needs according to the seasonal availability of resources. Despite the fact that these physiological changes have a strong genetic component, they are also functional and their intensity depends on the ecological conditions in which the animals live. The main ecological factors are more rain and limited supply of food and water, rather than external temperature. This discovery opens up a major line of research into the conservation of biodiversity on our planet today.

"It may seem surprising that until now there has not been a similar systematic study to prove or disprove whether it is only ectotherms that leave these marks in their bones during growth. In fact, there are so many things we do not know that science does not always advance in a linear way. The ideas somehow had long been wandering among the scientific community, but the work we have published organizes them and bases them on data," says researcher Meike Khler.

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Dinosaurs were warm-blooded reptiles: Mammal bone study sheds light on dinosaur physiology

Joseph Moss from D.H. Conley High School is among 28 middle and high school science teachers in 21 states to receive 2010 Frontiers in Physiology Online Professional Development Fellowships from the American Physiological Society (APS).

The new online professional development course allows the Frontiers teacher fellows to explore effective teaching strategies, understand the research process, and strategically enhance classroom lessons. From April 2010 to April 2011, teachers are engaged in course assignments, hands-on activities and online experiments, and discussions with one another across the nation. The lessons are structured in the APS Six Star Science framework for promoting excellence in science education. The research-based Six Star Science principles address student-centered learning, equity and diversity, technology in the classroom, authentic assessment on content and pedagogy, updated content, and reflection on the practice of teaching and learning.

Frontiers teacher fellows are mentored through the course by two former Frontiers teacher fellows who have undertaken roles as teacher mentors and APS Education Office staff.

For the complete article, please pick up a copy of The Daily Reflector. Current home delivery and electronic edition subscribers may log in to access this article at no charge. To become a subscriber, please click here or contact Customer Service at (252) 329-9505.

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News | Evolution

Evidence is mounting against claims that dinosaurs could not have been endothermic, including a new analysis of fossil microstructures found in ruminants, lizards, dinosaurs and crocodiles

By Brian Switek and Nature magazine | June 27, 2012|

Studying modern mammals can provide insights into the metabolism of dinosaurs. Image: Walter Myers /Stocktrek Images/Corbis

Why do testicles hang the way they do? Is there an adaptive function to the female orgasm? What does it feel like to want to kill yourself? Does free will...

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From Nature magazine

From museums to Hollywood films, dinosaurs are portrayed as highly active animals, but how they maintained this lifestyle isnt clear. For decades, palaeontologists have debated whether the physiology of non-avian dinosaurs was akin to that of today's cold-blooded reptiles or warm-blooded mammals. An important clue has now been uncovered not in Triceratops and its relatives, but in herbivorous mammals.

Palaeontologists have often examined bone microstructure in their investigations of dinosaur growth and physiology. Key to arguments on the subject are lines of arrested growth (LAGs) that represent an annual slowdown typically tied to a cold or dry season during which resources are scarce. These rings are seen in dinosaurs, as well as in creatures such as lizards and crocodiles, whose body temperatures are regulated by the external environment, but have not often been observed in the bones of endotherms creatures such as mammals that maintain high, constant body temperatures. But in a study published today in Nature, palaeontologist Meike Khler at the Autonomous University of Barcelona in Bellaterra, Spain, and her colleagues report that LAGs are present in ruminants from the tropics to the poles, greatly altering the context of the dinosaur-physiology debate.

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Dinosaurs Might Have Had Warm-Blooded Animals' Fast Metabolism

Studying modern mammals can provide insights into the metabolism of dinosaurs.

Walter Myers /Stocktrek Images/Corbis

From museums to Hollywood films, dinosaurs are portrayed as highly active animals, but how they maintained this lifestyle isnt clear. For decades, palaeontologists have debated whether the physiology of non-avian dinosaurs was akin to that of today's cold-blooded reptiles or warm-blooded mammals. An important clue has now been uncovered not in Triceratops and its relatives, but in herbivorous mammals.

Palaeontologists have often examined bone microstructure in their investigations of dinosaur growth and physiology. Key to arguments on the subject are lines of arrested growth (LAGs) that represent an annual slowdown typically tied to a cold or dry season during which resources are scarce. These rings are seen in dinosaurs, as well as in creatures such as lizards and crocodiles, whose body temperatures are regulated by the external environment, but have not often been observed in the bones of endotherms creatures such as mammals that maintain high, constant body temperatures. But in a study published today in Nature1, palaeontologist Meike Khler at the Autonomous University of Barcelona in Bellaterra, Spain, and her colleagues report that LAGs are present in ruminants from the tropics to the poles, greatly altering the context of the dinosaur-physiology debate.

Although LAGs have been found in mammalian bones before, Khler notes, this is the most comprehensive study of the structures in modern mammals across a range of latitudes. The herbivorous, hoofed mammals all slow their growth when faced with harsh conditions. This is the best way to cope with a cold or dry season, Khler says to shut down the energy demands of the body. The slowdown produces LAGs, even in endothermic organisms, and is an ancient mechanism for coping with lean times.

This means that LAGs cannot be used as an argument that dinosaurs could not have been endothermic, Khler says. In fact, the type of bone tissue seen in between dinosaur LAGs indicates the animals grew rapidly and sustained high metabolic rates. Dinosaur bone tissue is indistinguishable from that of todays endothermic ruminants, Khler says, meaning that dinosaurs were endothermic, too.

Anatomist John Hutchinson of London's Royal Veterinary College says that the study puts a nail in the coffin for the idea that mammals do not routinely exhibit LAGs as a natural part of their growth. And Hutchinson agrees that the study may help us to better understand dinosaur physiology.

Although he notes that the argument over dinosaur physiology involves a number of factors including histology and adaptations for rapid movement Hutchinson says that Khler's study provides additional evidence for dinosaur endothermy. The growing weight of evidence has been winning over scientists, myself included, to the view that endothermy evolved quite early in dinosaurs and was inherited by birds, he says.

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Published 6/26/2012 in News

AP: KU Med gets $1 million for physiology professor

KANSAS CITY, Kan. (AP) The University of Kansas Medical Center will use a $1 million gift to create a physiology professorship.

The university's endowment announced the gift Monday from Jim Osborn of Honolulu.

The gift honors Osborn's daughter, who worked in physiology at the medical center in 1968 and 1969 before dying in a car accident in 1970. At the time of her death, Kathleen Osborn was a junior at the University of Missouri.

Paul Cheney, chairman of the molecular and integrative physiology department, is the first recipient of the Kathleen M. Osborn Chair in Molecular and Integrative Physiology.

Osborn and his wife, Marion, already established the Kathleen Osborn Lectureship at the medical center. And Osborn established the Marion M. Osborn Professorship for Reproductive Science at the Kansas School of Medicine.

AP: Dodge City preparing to welcome disabled riders

DODGE CITY (AP) Dodge City is preparing to welcome 16 physically challenged veterans who are riding bicycles across the country to show people that they aren't defined by those challenges.

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CARTOON character Popeye is right to down a can of spinach when he wants his biceps to bulge, according to a Swedish study showing why the leafy vegetable makes us stronger.

Researchers at the Karolinska Institute in Stockholm said they had conducted a study showing how nitrate, found naturally in spinach and several other vegetables, tones up muscles.

For the study, to be published in the Journal of Physiology, the research team placed nitrate directly in the drinking water of a group of mice for one week and then dissected them and compared their muscle functions to that of a control group.

"The mice that had been on consistent nitrate had much stronger muscles," they said.

The nitrate used "was equivalent to a human's consumption of about 200 to 250 grams of spinach a day, so it's a very easily obtained amount", one of the researchers at the Department of Physiology and Pharmacology, Andres Hernandez, said.

While no effect could be seen in the so-called slow-twitch muscles used for moderate exercise and endurance, the scientists saw a clear change in the fast-twitch muscles used for strength and more high-intensity exercises, Mr Hernandez said.

The tricky question was determining why this happened.

The researchers discovered that the nitrates had prompted an increase in two proteins, found naturally in the muscles, that are used for storing and releasing calcium, which is vital to making muscles contract.

The protein increase in turn led to higher quantities of calcium released in the muscles, Mr Hernandez said, noting: "If you have more calcium released, you have a stronger contraction."

In human terms, consuming nitrates from, for instance, spinach increases the muscle strength available for things like lifting weights or sprinting up a steep hill.

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Popeye's right: spinach makes you stronger

DOVER, N.H.--(BUSINESS WIRE)--

iWorx, a developer of advanced physiology research tools, has introduced the IX-100BE Data Acquisition System with LabScribe2 Software that provides high resolution/low noise recording of biopotential signals for OEM applications. With one isolated input channel and a low voltage stimulator, the system is ideal for embedded biomedical and life science applications where only one biopotential recording channel is required.

The iWorx IX-100BE uses a 16-bit A/D converter to sample data over its full input range of 1V at speeds up to 200 kHz. The recorder also offers a wide selection of low pass and high pass filters and gains and is safe for human connection. The recorder incorporates a software programmable 16 bit, 5V stimulator (DAC). Parameters for the stimulator, such as pulse width, frequency and amplitude, may be changed on-the-fly. Standard protocols include Pulse, Train, and Step; protocols can be customized as well.

The iWorx IX-100BE recorder is controlled by LabScribe2 software, a powerful recording and analysis software package. LabScribe2 has an intuitive, user-friendly interface for setting up acquisition screens, calibrating signals and analyzing data. Up to 128 channels of data can be displayed simultaneously at sampling rates as high as 200,000 samples/second. A comprehensive set of analytical routines have been pre-configured making data analysis and interpretation quick and easy.

More information on iWorx IX-100BE Data Acquisition System can be found at http://www.iworx.com. Contact iWorx Systems, Inc., 62 Littleworth Road, Dover, NH 03820 (T) (800) 234-1757, (F) (603) 742-2455, billm@iworx.com.

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About iWorx iWorx advanced research solutions include high performance recording hardware, software, and components that accelerate metabolic, cardiovascular, neuromuscular and respiratory physiology research. In addition to data acquisition systems, iWorx offers a full selection of signal conditioners, stimulators, transducers, electrodes, cables, and general-purpose laboratory equipment and accessories.

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iWorx Introduces a High Performance, Single Channel Data Acquisition System with Analytical Software for Embedded OEM ...

Before I dive right into Benoit, it is important to have an understanding of what a concussion is and how it affects people. Concussions are the most common form of brain injury, yet they are still widely misunderstood.

Concussions occur when the brain strikes the interior surface of the skull. When a persons head is rapidly moved, the brain inside moves as well. The brain is not stationary, so rapid movements cause the brain to sway inside. As the brain impacts the skull, bruises are formed, and the bruising is what concussions are, on a basic level. Once a bruise (concussion) happens on the brain, it is there forever. The brain is made up of nerve cells, and oddly enough, nerve cells do not go through cell division. Cell division is how all our other cells get repaired when they are damaged.

Now, since these cells do not get repaired, it is critical that a person not suffer more than one concussion in the same area of the brain. By injuring the same spot over and over, you begin to develop severe deficits that will affect how you live your life.

This was the problem with Chris Benoit. It is my theory that due to Benoits style of wrestling, and signature moves he performed, it was likely that he suffered multiple concussions in the same area of the brain. June 24, 2007. Wow, has it really been that long? That night, the ECW Championship was to be won by the Rabid Wolverine, Chris Benoit. At the time, we were told that Benoit would not be able to make the event. We were left a bit confused and also a bit skeptical. This announcement could easily have been a swerve, or it could have been an appetizer to a brand new storyline.

The following night on Raw, we learned that Chris and his family had died. There were more questions than answers, and we were left with a hole in our wrestling hearts. Another great talent in the business died far too early. It was not until later in the month did we find out that something had happened to Chris that made him kill his family and then himself. The mainstream media jumped all over this tragic tale, stating that steroids were what made Benoit snap. Nobody seemed to consider any other options.

At the time, I was just beginning my paramedic career, and I knew very little about brain injuries and the impact they have on the rest of your life. Now, after many more years of medical experience, I feel confident that the Benoit tragedy was because the brain in Chris head had suffered so much impact over his incredible career that he no longer was able to differentiate right from wrong, reality from fantasy.

We all know that one of Chris trademark moves was the diving head butt. Even though he would not make head-to-head contact, he would still make impact with the shoulder and chest area of his opponent. Over time, his body realized that his head was making constant impacts, and it began tosend more calcium to skull to protect it. Calcium is what our bones are made up of. The skull, which is the only bone in the body to protect the brain, built up calcium on the front of his skull. This calcium deposit, over time, provided extra strength to the bone itself so it would not develop a stress fracture.

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Brain Physiology and the Chris Benoit Tragedy

By Madeline Haller Men's Health

Prepping for a big presentation but can't seem to remember any of the content? Blame your sweet tooth.

A diet high in sugar may hamper your memory and ability to learn, says a study published in the Journal of Physiology.

Researchers had two groups of rats drink water mixed with fructose, a type of sugar. One of the groups also received omega-3 fatty acids as a part of their diet. After 6 weeks, the rats who drank only sugar water completed a maze slower than the omega-3-fed mice. (We know you're not a mouse -- but you can still take steps to navigate the maze of life. Check out these 27 Ways to Power Up Your Brain.)

Not only were they slower in the maze, the rats who drank only sugar water had higher triglyceride, glucose, and insulin levels. It appears that they entered a state of insulin resistance, which is where the hormone insulin becomes less effective at lowering your blood sugar, says Fernando Gomez-Pinilla, Ph.D., lead study author and a professor of neurosurgery at the David Geffen School of Medicine at UCLA.

Why did sugar wreak havoc on their system?

Here's how it works: Insulin, in addition to controlling blood sugar, also influences the ways in which your brain cells operate. And within the hippocampus -- the part of the brain responsible for short-term and long-term memory -- insulin signaling actually facilitates memory. Therefore, an insulin resistance may be what's causing a disruption in the rats' ability to recall the route they'd learned 6 weeks ago, the researchers hypothesize.

But the good news is, omega-3 fatty acids appeared to have protective effect on the brain.

How so? Although the researchers are unaware of what's happening on a molecular level in the brain, Gomez-Pinilla says it may have to do with the large amount of DHA (the type of omega-3 fatty acid they monitored in the study) that's already present in the brain.

So could sugar slow down your brain, too? The researchers say yes. But since the study monitored the rats for nearly two months, the effect on humans would take several years of exposure to fructose to see these effects. (If you're looking to wean yourself off of sugar, check out these 9 Sneaky Ways to Eat Less.)

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Do sugary snacks make you stupid?

Public release date: 20-Jun-2012 [ | E-mail | Share ]

Contact: Dr. Ben Novak Ben.Novak@rub.de 49-234-322-4331 Ruhr-University Bochum

Apply the ointment, light on, light off that's how easy it is to cure various forms of non-melanoma skin cancer. However, the majority of patients suffer severe pain during the so-termed photodynamic therapy. Why the treatment with ointment and red light can be so painful has now been uncovered by researchers from the RUB. They identified the ion channels involved and signalling molecules secreted by the cancer cells. "The results may provide a starting point for suppressing the pain", says Dr. Ben Novak of the Department of Animal Physiology.

How the photodynamic therapy works

In contrast to normal cells, cancer cells are equipped with different enzymes and have a much higher metabolism. If you apply a molecule called aminolevulinic acid to the skin in the form of a gel, cancer cells take up considerably more of this substance than healthy cells. If aminolevulinic acid accumulates in the cells, the mitochondria the power plants of the cells form the molecule protoporphyrin IX. When irradiated with red light, protoporphyrin IX reacts with oxygen. This produces highly reactive oxygen species, free radicals, which destroy the cancer cells. Approximately ten minutes of red light irradiation is sufficient to successfully treat superficial forms of non-melanoma skin cancers such as actinic keratosis. Doctors also remove warts in this way.

Painful therapy

"The catch is: it's terribly painful", says Ben Novak. Forty percent of those treated experience pain during the light irradiation, which they assess on a scale of 0 to 10 (whereby 10 corresponds to an excruciating pain like a heart attack) as 7 to 8. Using injections, like at the dentist, it is possible to numb the nerves involved. "But that also always involves a risk", says the Bochum biologist. The scientists led by the RUB professor Dr. Hermann Lbbert have now solved the mystery as to why the treatment hurts at all.

Pain-sensitive cells in the skin are stimulated

The pain is generated by two mechanisms. In a cell culture experiment, the team showed that not only cancer cells but also pain-sensitive nerve cells in the skin take up aminolevulinic acid and its derivative methyl aminolevulinic acid from the ointment. Using calcium imaging, the animal physiologists followed the activity of nerve cells which they had treated with aminolevulinic acid and cells that were not exposed to the substance. Treated nerve cells fired when the researchers exposed them to light. In a living organism, this would mean that the cells would send a pain stimulus to the brain. Without the aminolevulinic acid, the pain-sensitive cells remained inactive under red light. In further experiments, the scientists showed that the activity of the nerve cells is caused by sodium channels and voltage-gated calcium channels in the cell membrane. "A drug that targets these channels would, conceivably, be able to suppress the pain but that's still in the future", says Ben Novak.

Tumour cells alert nerve cells

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Double the pain: RUB biologists find the cause of pain in the treatment of fair skin cancer

Changing lifestyles and busier work schedules are inducing changes in the physiology leading to an increase in numbers of working professionals to opt for fertility treatments. These in turn lead to the numbers of multiple births at hospitals in the city. In effect, multiple births come with a higher risk of developing complications along with added expenses.

While the government hospitals stated that the numbers of twins being born in hospitals across the city have notably increased in the past year, prominent fertility clinics affirmed the same. According to the fertility clinics, the reason can be attributed to busier lifestyles of people, especially working full-time.

Doctors point out that due to hectic work schedules, factors such as irregular food habits leading to obesity, inverted sleep cycles may contribute to growing cases of infertility. More number of couples are thus opting for fertility treatments, relying on various fertility drugs to help them conceive. Moreover, age is another issue that needs to be factored into the matter. According to Dr. Sarat Battina, the infertility specialist at Apollo hospital, Upto 35 years of age, a woman is in the most fertile phase. Between 35 and 39, she enters into a plateau zone and finally 40 years onwards, her chances of conceiving begin to drop steadily.

According to a fertility specialist, normally for a single embryo, a woman goes upto nine months before her delivery. The gestation period is shorter for multiple births. Due to a reduced gestation period, the fetuses have lesser time to develop thus requiring the support of incubators after birth thereby increasing the chances of infant mortality. As a result of these factors, the mother goes into preterm labor which can have several complications risking the life of the unborn child along with the mother.

Shedding light on the likelihood of side effects of fertility drugs, a senior official of the Institute of Obstetrics & Gynecology (IOG) said, "Patients who use certain fertility drugs, need to be closely monitored as there can be possible side effects such as accumulation of fluid in the lungs and other body cavities."

Referring to the science of the issue, fertility treatment drugs, especially gonadotropin used to induce ovulation, causes generation of multiple ova increasing the likelihood of fertilisation of more than one ovum. Patients using fertility treatment therefore require close monitoring. We monitor them very closely. We ask them to come in every day or atleast every alternate day to the clinic for a checkup, said Dr. Battina.

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More twin births in the city

// ?> The family life of elephants has been eulogised since time immemorial. Now we've discovered their unique physiology during pregnancy; Earth Times

Inside your ovaries is a yellow body called the corpus luteum (Latin for yellow body.) it secretes the progesterone which maintains your baby during early pregnancy. Now the parasitic nature of mammalian babies, feeding from the mother's blood, is rarely recognised. It is unique in physiology but varies among the placental mammals in how the anatomy adapts.

In this case, the ovary has an average of 5.4 (multiple) yellow bodies in the elephant and a 12-16 week oestrous cycle, as compared with 4 weeks in humans, and a single yellow body for each child. Again, where humans start secreting progesterone from the placenta, to replace that from the yellow body, elephants don't!

Fifteen pregnant Asian and two pregnant African elephants were examined in zoos for this paper published in the Proceedings of the Royal Society B: Biological Sciences, today, using ultrasound scans. A mean length of pregnancy of 647 days (22 months) was observed. The researchers, primarily from the Leibniz Institute in Berlin, comprise of Imke Lueders, Cheryl Niemuller, Peter Rich, Charlie Gray, Robert Hermes, Frank Goeritz and Thomas B. Hildebrandt. These scans give some idea of how they observed the embryos developing with many yellow bodies (CL) in the ovaries:

Credit: Imke Lueders

Ultrasonographic images from the ovary

(a) Ovulatory ovary showing multiple corpora lutea (CLs), (i), ovulatory CL, (ii), acCLS, arrow heads, ovarian border (day 162);

(b) depicts minimal blood streams of two CL

What happened was that auxiliary yellow bodies (or CLs) formed in addition to the one CL per child we would have in women. With no hormone coming from the placenta later, these multiple CLs provide progesterone with which to maintain the uterus lining for all stages of the long pregnancy.

The only other known method of supplying the hormone is from the foetus' gonads. This surprising self-preservation method however may not actually be used by elephants. This anatomical variation in the ovary is the key to maintaining that long gestation. (The lengthy pregnancy is thought to slow ageing in order to push the average life-span to 65 years).

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Elephant pregnancy is unique

Editor's Choice Main Category: Sports Medicine / Fitness Also Included In: Endocrinology Article Date: 19 Jun 2012 - 0:00 PDT

Current ratings for: 'Do Testosterone And Growth Hormones Impact On Muscle Building? Study Says They Don't'

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Daniel West, graduate student in the Department of Kinesiology at McMaster, and lead author in both studies, explained that many people, including experts, have been convinced for a long time that anabolic hormones are vital for muscle protein synthesis, a process that eventually leads to larger muscles.

West said:

Participants managed to make new muscle protein at the same rate, despite huge differences in testosterone levels

As muscle proteins eventually lead to muscle growth, their finding was an important one, the authors explained.

West said:

Muscle mass gains ranged from negligible to over 12 pounds (about 5 kilograms). However, the scientists found no relationship between muscle growth and their levels of testosterone and growth hormone after exercise. In other words, muscle growth or strength increase were not linked to growth hormone or testosterone levels.

Muscle growth and strength increases were not associated with raised levels of testosterone or growth hormones after weight training

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Do Testosterone And Growth Hormones Impact On Muscle Building? Study Says They Don't

Brookhaven researchers Jilian Fan, Changcheng Xu, and Chengshi Yan with cultures of algae that were shown to increase oil production in response to excess carbon.

(Phys.org) -- Overturning two long-held misconceptions about oil production in algae, scientists at the U.S. Department of Energys Brookhaven National Laboratory show that ramping up the microbes overall metabolism by feeding them more carbon increases oil production as the organisms continue to grow. The findings published online in the journal Plant and Cell Physiology on May 28, 2012 may point to new ways to turn photosynthetic green algae into tiny green factories for producing raw materials for alternative fuels.

We are interested in algae because they grow very quickly and can efficiently convert carbon dioxide into carbon-chain molecules like starch and oils, said Brookhaven biologist Changcheng Xu, the papers lead author. With eight times the energy density of starch, algal oil in particular could be an ideal raw material for making biodiesel and other renewable fuels.

But there have been some problems turning microscopic algae into oil producing factories.

For one thing, when the tiny microbes take in carbon dioxide for photosynthesis, they preferentially convert the carbon into starch rather than oils. Normally, algae produce very little oil, Xu said.

Before the current research, the only way scientists knew to tip the balance in favor of oil production was to starve the algae of certain key nutrients, like nitrogen. Oil output would increase, but the algae would stop growing not ideal conditions for continuous production.

Another issue was that scientists didnt know much about the details of oil biochemistry in algae. Much of what we thought we knew was inferred from studies performed on higher plants, said Brookhaven biochemist John Shanklin, a co-author whos conducted extensive research on plant oil production. Recent studies have hinted at big differences between the microbial algae and their more complex photosynthetic relatives.

Enlarge

Confocal image of the algae Chlamydomonas showing the accumulation of oil droplets (golden dots). Red represents chlorophyll autofluorescence.

The scientists grew cultures of Chlamydomonas reinhardtii the fruit fly of algae under a variety of nutrient conditions, with and without inhibitors that would limit specific biochemical pathways. They also studied a mutant Chlamydomonas that lacks the capacity to make starch. By comparing how much oil accumulated over time in the two strains across the various conditions, they were able to learn why carbon preferentially partitions into starch rather than oil, and how to affect the process.

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Carbon is key for getting algae to pump out more oil

Consumption of soft drinks and other sweetened beverages is not a major contributor to the rising levels of childhood obesity, according to Canadian research that assesses consumption and risk in over 10,000 children and youths.

The study published in Applied Physiology, Nutrition, and Metabolism examines the relationship between beverage intake patterns of Canadian children and their risk for obesity. Led by Susan Whiting of the University of Saskatchewan, Canada, the researchers revealed that sweetened beverage intake is not a risk factor for childhood obesity in most agree groups, noting that intake seems to be a risk factor only in boys aged 6-11.

Whiting and her colleagues revealed that whilst many children and youths consume soft drinks and other sweetened beverages such as fruit punch and lemonade almost all groups are not at any higher risk for obesity than their peers who drink healthier beverages.

"We found sweetened drinks to be dominant beverages during childhood, but saw no consistent association between beverage intake patterns and overweight and obesity," said Whiting.

However, the lead researcher noted that overconsumption of sweetened beverages may put some children at increased risk for overweight and obesity, especially as consumption habits formed early in life and are often maintained into adulthood.

Indeed, boys aged 6-11 years who consumed mostly soft drinks were shown to be at increased risk for overweight and obesity as compared with those who drank a more moderate beverage pattern," she revealed.

Study details

The researchers noted that sweetened beverage intake has risen in past decades. This increase in consumptions has been matched with a rise in prevalence of overweight and obesity among children.

Our objective was to examine the relationship between beverage intake patterns and overweight and obesity among Canadian children.

The research team determined beverage consumption patterns among Canadian children aged between two years old and 18 years old using cluster analysis where socio-demographics, ethnicity, household income, and food security were significantly different across the clusters.

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Soft drinks are not the major contributor to childhood obesity, say researchers

Newswise New research from scientists at McMaster University reveals exercise-related testosterone and growth hormone do not play an influential role in building muscle after weightlifting, despite conventional wisdom suggesting otherwise.

The findings indicate that bodybuilders who look to manipulate those hormones through exercise routines are wasting their time.

In two separate studies, published in the Journal of Applied Physiology and the European Journal of Applied Physiology, researchers found anabolic hormoneslong thought to be essential for building a muscular framedo not influence muscle protein synthesis, the process that leads to bigger muscles.

A popular mindset for weightlifters is that increased levels of hormones after exercise play a key role in building muscle, explains Daniel West, lead author of both studies and a graduate student in the Department of Kinesiology at McMaster. That is simply not the case.

In the first study, researchers examined the responses of both male and female participants to intense leg exercise. Despite a 45-fold difference in testosterone increase, men and women were able to make new muscle protein at exactly the same rate.

Since new muscle proteins eventually add up to muscle growth, this is an important finding, says West.

While testosterone is definitely anabolic and promotes muscle growth in men and women at high doses, such as those used during steroid abuse, our findings show that naturally occurring levels of testosterone do not influence the rate of muscle protein synthesis.

In the second study, researchers analyzed the post-exercise hormonal responses of 56 young men, aged 18 to 30, who trained five days a week for 12 weeks in total.

The men experienced gains in muscle mass that ranged from virtually nothing to more than 12 pounds, yet their levels of testosterone and growth hormone after exercise showed no relationship to muscle growth or strength gain.

Surprisingly, the researchers noted that cortisolconsidered to have the opposite effect of anabolic hormones because it reduces protein synthesis and breaks down tissuewas related to the gain in muscle mass.

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Research Debunks Bodybuilding Hormone Myth: Growth Promoting Hormones Don't Promote Growth or Strength

Public release date: 14-Jun-2012 [ | E-mail | Share ]

Contact: Michelle Donovan donovam@mcmaster.ca 905-525-9104 McMaster University

New research from scientists at McMaster University reveals exercise-related testosterone and growth hormone do not play an influential role in building muscle after weightlifting, despite conventional wisdom suggesting otherwise.

The findings indicate that bodybuilders who look to manipulate those hormones through exercise routines are wasting their time.

In two separate studies, published in the Journal of Applied Physiology and the European Journal of Applied Physiology, researchers found anabolic hormoneslong thought to be essential for building a muscular framedo not influence muscle protein synthesis, the process that leads to bigger muscles.

"A popular mindset for weightlifters is that increased levels of hormones after exercise play a key role in building muscle," explains Daniel West, lead author of both studies and a graduate student in the Department of Kinesiology at McMaster. "That is simply not the case."

In the first study, researchers examined the responses of both male and female participants to intense leg exercise. Despite a 45-fold difference in testosterone increase, men and women were able to make new muscle protein at exactly the same rate.

"Since new muscle proteins eventually add up to muscle growth, this is an important finding," says West.

"While testosterone is definitely anabolic and promotes muscle growth in men and women at high doses, such as those used during steroid abuse, our findings show that naturally occurring levels of testosterone do not influence the rate of muscle protein synthesis."

In the second study, researchers analyzed the post-exercise hormonal responses of 56 young men, aged 18 to 30, who trained five days a week for 12 weeks in total.

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Research debunks bodybuilding myth: Growth-promoting hormones don't stimulate strength

Public release date: 14-Jun-2012 [ | E-mail | Share ]

Contact: Susan J. Whiting susan.whiting@usask.ca Canadian Science Publishing (NRC Research Press)

Ottawa, Ontario (June 14, 2012) Most children and youth who consume soft drinks and other sweetened beverages, such as fruit punch and lemonade, are not at any higher risk for obesity than their peers who drink healthy beverages, says a new study published in the October issue of Applied Physiology, Nutrition, and Metabolism. The study examined the relationship between beverage intake patterns of Canadian children and their risk for obesity and found sweetened beverage intake to be a risk factor only in boys aged 6-11.

"We found sweetened drinks to be dominant beverages during childhood, but saw no consistent association between beverage intake patterns and overweight and obesity," says lead author Susan J. Whiting. "Food and beverage habits are formed early in life and are often maintained into adulthood. Overconsumption of sweetened beverages may put some children at increased risk for overweight and obesity. Indeed, boys aged 6-11 years who consumed mostly soft drinks were shown to be at increased risk for overweight and obesity as compared with those who drank a more moderate beverage pattern."

The authors determined beverage consumption patterns among Canadian children aged 2 years using cluster analysis where sociodemographics, ethnicity, household income, and food security were significantly different across the clusters. Data were divided into different age and gender groups and beverage preferences were studied. For this study the sweetened, low-nutrient beverages, categorized according to Canada's Food Guide, consisted of fruit-flavoured beverages, beverages with less than 100% fruit juice, lemonades, regular soft drinks, and sweetened coffees or teas.

The authors found the main predictors of childhood obesity in Canadian children were household income, ethnicity, and household food security.

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The study "Beverage patterns among Canadian children and relationship to overweight and obesity" appears in the October issue of Applied Physiology, Nutrition, and Metabolism.

For more information contact: Corresponding author: Susan J. Whiting (e-mail: susan.whiting@usask.ca).

Full Reference: Danyliw, A.D., Vatanparast, H., Nikpartow, N., and Whiting, S.J. Beverage patterns among Canadian children and relationship to overweight and obesity. Applied Physiology, Nutrition, and Metabolism, 37(5) doi: 10.1139/ H2012-0074. [This article is available Open Access at http://www.nrcresearchpress.com/doi/abs/10.1139/H2012-074%5D

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Soft drink consumption not the major contributor to childhood obesity

Public release date: 14-Jun-2012 [ | E-mail | Share ]

Contact: Jesslyn Tenhouse Chew ChewJ@missouri.edu 573-882-8353 University of Missouri-Columbia

COLUMBIA, Mo. Childhood obesity has increased dramatically throughout the past 40 years and has been tied to many health problems. Now, a University of Missouri researcher has found that children's weight is associated with their math performance.

"The findings illustrate the complex relationships among children's weight, social and emotional well-being, academics and time," said Sara Gable, associate professor in the MU Department of Nutrition and Exercise Physiology, who led the study.

Gable looked at more than 6,250 children from the Early Childhood Longitudinal Study-Kindergarten Cohort, a nationally representative sample. The children were followed from the time they started kindergarten through fifth grade. At five points in time, parents provided information about their families, teachers reported on the children's interpersonal skills and emotional well-being, and children were weighed and measured; they also took academic tests.

When compared with children who were never obese, boys and girls whose obesity persisted from the start of kindergarten through fifth grade performed worse on the math tests, starting in first grade. Their lower performance continued through fifth grade. For boys whose obesity emerged laterin third or fifth gradeno such differences were found. For girls who became obese later, poorer math performance was temporary.

In addition, for girls who were persistently obese, having fewer social skills explained some part of their poorer math performance. For both boys and girls who were persistently obese, feeling sadder, lonelier and more anxious also explained some of their poorer math performance.

"Our study suggests that childhood obesity, especially obesity that persists throughout the elementary grades, can harm children's social and emotional well-being and academic performance," Gable said.

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The study, "Boys' and Girls' Weight Status and Math Performance from Kindergarten Entry through Fifth Grade: A Mediated Analysis," was published in the journal Child Development. The study was supported by the United States Department of Agriculture's Economic Research Service through its Food Assistance and Nutrition Research Program. Researchers from the University of Vermont and the University of California, Los Angeles assisted Gable with the study.

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Childhood obesity linked to math performance, MU researcher says

DUBLIN--(BUSINESS WIRE)--

Research and Markets (http://www.researchandmarkets.com/research/2fnxxj/3d_displays) has announced the addition of John Wiley and Sons Ltd's new book "3D Displays" to their offering.

This book addresses electrical engineers, physicists, designers of flat panel displays (FDPs), students and also scientists from other disciplines interested in understanding the various 3D technologies. A timely guide is provided to the present status of development in 3D display technologies, ready to be commercialized as well as to future technologies.

Having presented the physiology of 3D perception, the book progresses to a detailed discussion of the five 3D technologies: stereoscopic and autostereoscopic displays; integral imaging; holography and volumetric displays, and:

- Introduces spatial and temporal multiplex for the two views needed for stereoscopic and autostereoscopic displays;

- Outlines dominant components such as retarders for stereoscopic displays, and fixed as well as adjustable lenticular lenses and parallax barriers for auto- stereoscopic displays;

- Examines the high speed required for 240 Hz frames provided by parallel addressing and the recently proposed interleaved image processing;

- Explains integral imaging, a true 3D system, based on the known lenticulars which is explored up to the level of a 3D video projector using real and virtual images;

- Renders holographic 3D easier to understand by using phasors known from electrical engineering and optics leading up to digital computer generated holograms;

- Shows volumetric displays to be limited by the number of stacked FPDs; and,

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Research and Markets: 3D Displays