Day: 11/03/2014

Gut microbes changed rapidly as humans evolved › News in Science.

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As humans diverged from apes our gut flora evolved rapidly to become more specialised for meat-based diets, a new study finds.

The report, published today in Proceedings of the National Academy of Sciences , also shows that on this evolutionary journey, the diversity of our gut bacteria was drastically reduced.

First author Andrew Moeller, a doctoral student in the Department of Ecology and Evolutionary Biology at Yale University, says humans are essentially ecosystems containing trillions of micro-organisms.

Yet how the body’s microbial ecosystem has evolved is only beginning to be revealed, he says.

“By looking at how it changed recently in human evolution, I hope we are setting the stage to understand the deeper evolutionary history of the microbiome,” Moeller says.

The team sequenced a gene called the 16S rDNA, which is a gene present in all bacteria, in samples from 416 wild chimpanzees, bonobos and gorillas collected from sites throughout Africa by primatologists working in the field.

They then compared this information to gut microbiome data from 638 humans living in a range of conditions from hunter-gatherer lifestyles to suburban America.

Despite marked differences among the microbiomes of humans and African ape species, Moeller says there is a shared set of bacterial taxa.

This potentially represents the ancestral core of the African ape microbiome, he says.

Loss of diversity

The team found that while the “mean level” of microbial diversity differed substantially among individual apes, the microbiomes of humans were the least diverse.

“This trend does not appear to be the result of any specific cultural practice and is apparent in humans regardless of whether they resided in cities in the United States, small towns in Malawi or rural villages in the Amazonas,” Moeller writes.

He says this loss of diversity could be due to a number of factors including the move to an indoor lifestyle, improved hygiene, antibiotic use and meat eating.

Microbes associated with diets rich in animal fat and protein, have increased since humans evolved from apes, while those associated plants have decreased (iStockphoto: Eraxion)

However Moeller says there could be a downside to this loss.

“We know many microbes in the microbiome are beneficial, so it’s possible humans are missing out on some of these benefits. In particular a loss of bacterial diversity may negatively influence the function of our immune systems.”

The study also shows that “consistent with known dietary shifts in human evolution, taxa associated with the digestion of animal foodstuffs have risen in relative abundance in the human microbiome, whereas taxa that have been associated with the digestion of plant-based diets have become less prominent”.

By example, Bacteroides, which have been positively associated with diets rich in animal fat and protein, have increased fivefold in humans since the divergence of Homo and Pan (the chimpanzee family) some 13 million years ago.

At the same time, Fibrobacter, a common plant-fermenting bacterial genus of the wild apes microbiome is greatly reduced in humans.

Moeller says there are obvious difficulties with extrapolating modern-day data to ancient times, but likens the approach to detective work.

“We can never be 100 per cent sure of events that happened millions of years ago,” he says.

“We can look at the evidence today and piece together an explanation of our observations.

“In this case, all the evidence points to the same conclusion that human microbiomes are less diverse today than they were in our ancestors.”

Religion vs. Humanism: Isaac Asimov on Science and Spirituality .

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Science and religion have a long history of friction as diametric opposites. But some of humanity’s greatest minds have found in science itself a rich source of spirituality, from Albert Einstein’s meditation on whether scientists prayto Richard Feynman’s ode to the universe to Carl Sagan on the reverence of science to Bucky Fuller’s scientific rendition of The Lord’s Prayerto Richard Dawkins on the magic of reality.

Here comes a wonderful addition from the mind of beloved science fiction author Isaac Asimov, found in the altogether indispensable It’s Been a Good Life (public library) — a revealing selection of Asimov’s letters, diary entries, and his three prior autobiographies, In Memory Yet Green (1979), In Joy Still Felt (1980), and the posthumously publishedI. Asimov: A Memoir (1994), edited by his spouse, Janet Jeppson Asimov, a decade after his death.

Asimov succinctly recapitulates his philosophy:

I have never, not for one moment, been tempted toward religion of any kind. The fact is that I feel no spiritual void. I have my philosophy of life, which does not include any aspect of the supernatural and which I find totally satisfying. I am, in short, a rationalist and believe only that which reason tells me is so.

Indeed, rather than suspending his conviction in the ether of vacant self-righteousness, it is with amiable reason and clever logic that Asimov responds to his inquisitors: Shortly after writing Asimov’s Guide to the Bible, he appeared on the David Frost Show and delivered his irreverent wit in full brilliance when badgered with the G-question. The author recounts:

[Frost] said, with neither warning nor preamble, “Dr. Asimov, do you believe in God?”

“That rather took my breath away. It was a dreadful way of putting a person on the spot. To answer honestly, “No,” with millions of people watching, could arouse a great deal of controversy I didn’t feel much need of. Yet I couldn’t lie, either. I played for time, in order to find a way out.

He said, “Dr. Asimov, do you believe in God?”

And I said, “Whose?”

He said, a little impatiently, “Come, come, Dr. Asimov, you know very well whose. Do you believe in the Western God, the God of the Judeo-Christian tradition?”

Still playing for time, I said, “I haven’t given it much thought.”

Frost said, “I can’t believe that, Dr. Asimov.” He then nailed me to the wall by saying, “Surely a man of your diverse intellectual interests and wide-ranging curiosity must have tried to find God?”

(Eureka! I had it! The very nails had given me my opening!) I said, smiling pleasantly, “God is much more intelligent than I am — let him try to find me.”

 

Above all, however, Asimov was an unrelenting humanist:

I’ve never been particularly careful about what label I placed on my beliefs. I believe in the scientific method and the rule of reason as a way of understanding the natural Universe. I don’t believe in the existence of entities that cannot be reached by such a method and such a rule and that are therefore “supernatural.” I certainly don’t believe in the mythologies of our society, in Heaven and Hell, in God and angels, in Satan and demons. I’ve thought of myself as an “atheist,” but that simply described what I didn’t believe in, not what I did.

Gradually, though, I became aware that there was a movement called “humanism,” which used that name because, to put it most simply, Humanists believe that human beings produced the progressive advance of human society and also the ills that plague it. They believe that if the ills are to be alleviated, it is humanity that will have to do the job. They disbelieve in the influence of the supernatural on either the good or the bad of society, on either its ills or the alleviation of those ills.

He revisits the subject of self-classification in a letter to a friend, articulating the same gripe with the label “atheist” that Brian Cox would come to echo decades later, and writes:

Have I told you that I prefer “rationalism” to “atheism”? The word “atheist,” meaning “no God,” is negative and defeatist. It says what you don’t believe and puts you in an eternal position of defense. “Rationalism” on the other hand states what you DO believe; that, that which can be understood in the light of reason. The question of God and other mystical objects-of-faith are outside reason and therefore play no part in rationalism and you don’t have to waste your time in either attacking or defending that which you rule out of your philosophy altogether.

Speaking to the core belief that the unknown is a source of wonder rather than fear, a fundamental driver of science, Asimov allows for the possibility that his own convictions about the nonexistence of “god” might be wrong, with a playful wink at Bertrand Russell:

There is nothing frightening about an eternal dreamless sleep. Surely it is better than eternal torment in Hell and eternal boredom in Heaven. And what if I’m mistaken? The question was asked of Bertrand Russell, the famous mathematician, philosopher, and outspoken atheist. “What if you died,” he was asked, “and found yourself face to face with God? What then?”

And the doughty old champion said, “I would say, ‘Lord, you should have given us more evidence.’”

But Asimov’s philosophy shines with its fullest heart in these beautiful words penned at the end of his life, at once validating and invalidating the mortality paradox:

The soft bonds of love are indifferent to life and death. They hold through time so that yesterday’s love is part of today’s and the confidence in tomorrow’s love is also part of today’s. And when one dies, the memory lives in the other, and is warm and breathing. And when both die — I almost believe, rationalist though I am — that somewhere it remains, indestructible and eternal, enriching all of the universe by the mere fact that once it existed.

Ultracold disappearing act: ‘Matter waves’ move through one another but never share space.

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How can two clumps of matter pass through each other without sharing space? Physicists have documented a strange disappearing act by colliding Bose Einstein condensates that appear to keep their distance even as they pass through one another.
Physicist Randy Hulet and colleagues observed a strange disappearing act during collisions between forms of Bose Einstein condensates called solitons. In some cases, the colliding clumps of matter appear to keep their distance even as they pass through each other.

A disappearing act was the last thing Rice University physicist Randy Hulet expected to see in his ultracold atomic experiments, but that is what he and his students produced by colliding pairs of Bose Einstein condensates (BECs) that were prepared in special states called solitons.Hulet’s team documented the strange phenomenon in a new study published online this week in the journalNature Physics.

BECs are clumps of a few hundred thousand lithium atoms that are cooled to within one-millionth of a degree above absolute zero, a temperature so cold that the atoms march in lockstep and act as a single “matter wave.” Solitons are waves that do not diminish, flatten out or change shape as they move through space. To form solitons, Hulet’s team coaxed the BECs into a configuration where the attractive forces between lithium atoms perfectly balance the quantum pressure that tends to spread them out..

The researchers expected to observe the property that a pair of colliding solitons would pass though one another without slowing down or changing shape. However, they found that in certain collisions, the solitons approached one another, maintained a minimum gap between themselves, and then appeared to bounce away from the collision.

“You never see them together,” said Hulet, Rice’s Fayez Sarofim Professor of Physics and Astronomy. “There is always a hole, a gap that they must jump over. They pass through one another, but they never occupy the same space while they’re doing that.

“It happens because of ‘wave packet’ interference,” he said. “Think of them as waves that can have a positive or negative amplitude. One of the solitons is positive and the other is negative, so they cancel one another. The probability of them being in the spot where they meet is zero. They pass through that spot, but you never see them there.”

Hulet’s team specializes in experiments on BECs and other ultracold matter. They use lasers to both trap and cool clouds of lithium gas to temperatures that are so cold that the matter’s behavior is dictated by fundamental forces of nature that aren’t observable at higher temperatures.

To create solitons, Hulet and postdoctoral research associate Jason Nguyen, the study’s lead author, balanced the forces of attraction and repulsion in the BECs.

“First we make a Bose Einstein condensate and then we use a sheet of light to split the condensate in half and push the two halves apart,” Nguyen said. “We hold them apart and turn each of them into solitons, and then we take the sheet away and let them fall back toward one another and collide.”

Cameras captured images of the tiny BECs throughout the process. In the images, two solitons oscillate back and forth like pendulums swinging in opposite directions. Hulet’s team, which also included graduate student De Luo and former postdoctoral researcher Paul Dyke, documented thousands of head-on collisions between soliton pairs and noticed a strange gap in some, but not all, of the experiments.

“One of the defining features of a soliton is that they are supposed to be able to pass through one another and emerge unfazed,” Hulet said.

“Some of the collisions are consistent with that,” he said, pointing to images of two solitons oscillating, meeting, emerging and continuing on their cycle. “These two solitons certainly appear to have passed through one another.

“In another set of collisions, there’s always this gap between them,” he said, pointing to a different set of images. “It doesn’t look like they ever close that gap to be able to pass through. In fact, it looks like they’ve come together and then bounced off one another.”

Hulet said the idea of solitons bouncing away from one another had been around for about 40 years, based on longstanding observations of optical solitons in fiber-optic cables. In this scenario, the gap is viewed as evidence of a force that is pushing the solitons apart.

To probe more deeply, Hulet’s team needed to conduct a new set of experiments that focused on the one defining feature of a soliton that they couldn’t control — its phase.

The first soliton was observed in a canal in Scotland in 1834 and they’ve since been observed in magnets, fiber-optic cables, atomic nuclei and even swimming pools. Hulet’s team was among the first to report BEC “matter-wave bright solitons” in 2002.

Like a wave in the ocean or a light beam in a fiber-optic cable, solitons have a characteristic amplitude, frequency and phase. Hulet’s team could control the amplitude but they could not control the soliton’s phase.

“All waves oscillate in time,” Hulet said. “They have a frequency at which their amplitude becomes positive, negative, positive, negative and so on. The rate of that oscillation, how often it switches, defines their frequency. Where they begin that cycle is something we refer to as ‘the phase.’ It’s a kind of starting point.”

The wave’s phase is an angle that can vary between zero and 360 degrees. Waves that are “in-phase” have the same starting point, and waves that are “out-of-phase” are 180 degrees off, meaning that one begins at its peak while the other starts at its trough.

“When we saw the initial data we said, ‘This doesn’t make sense, because solitons are always supposed to pass through one another and these look like they’re bouncing instead,'” Hulet said. “So we began thinking about how we could tag one of the solitons to make it distinct so that we could follow its trajectory in time and see what it did.”

The team found a way to “tag” one soliton by making it larger than the other. In the next round of experiments, Nguyen and Luo captured pictures of collisions between different-sized solitons.

“We did that experiment over and over for many different relative phases, and we looked for two cases, one where the relative phase was zero, or in-phase, and another where it was 180 degrees, or completely out-of-phase,” Hulet said.

For the in-phase case, the team saw the two solitons pass through one another and emerge, just as predicted by theory.

“In the out-of-phase case, the one with the gap, where it appeared that they had been bouncing off of each other, we still saw the gap but we also saw the larger soliton emerge unfazed on the other side of the gap. In other words, it jumped through the gap!”

Hulet said the experiment confirmed the theory that solitons do pass through one another, even in cases where they are out-of-phase and only appear to bounce away from each other.

Many of the events that Hulet’s team measures occur in one-thousandth of a second or less. To confirm that the “disappearing act” wasn’t causing a miniscule interaction between the soliton pairs — an interaction that might cause them to slowly dissipate over time — Hulet’s team tracked one of the experiments for almost a full second.

The data showed the solitons oscillating back and fourth, winking in and out of view each time they crossed, without any measurable effect.

“This is great example of a case where experiments on ultracold matter can yield a fundamental new insight,” Hulet said. “The phase-dependent effects had been seen in optical experiments, but there has been a misunderstanding about the interpretation of those observations.”

Video: http://youtu.be/iAJ7XvKzte8

Story Source:

The above story is based on materials provided by Rice University. Note: Materials may be edited for content and length.

Journal Reference:

  1. Jason H. V. Nguyen, Paul Dyke, De Luo, Boris A. Malomed, Randall G. Hulet.Collisions of matter-wave solitons. Nature Physics, 2014; DOI:10.1038/nphys3135

Billy Graham’s My Answer: Is Suicide Always Wrong?

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endoflife Q:

The doctor says I have at most six months to live (because of lung cancer) and I know they aren’t going to be happy ones. Why would it be wrong for me to take my own life? I’ll just be a nuisance to my family if I hang around.

A:

I urge you as strongly as I possibly can not to take this drastic, final step, in spite of the uncertainty and pain you may be facing.

Why do I say this? One reason is because of the impact your actions would have on those you left behind. Right now, all you can think about is the inconvenience you may cause them as you grow weaker – but have you thought about the pain you’ll cause them if you end your life? Almost inevitably they will be filled with guilt and heartache, wondering what they might have done to help you and keep you from taking this step.

But there is a far more serious reason why I hope you won’t end your life right now:You aren’t ready to die. Elsewhere in your letter, you admit you’ve never paid much attention to God. But someday soon you will enter His presence – and you are not ready for that day. The Bible warns, “Man is destined to die once, and after that to face judgment” (Hebrews 9:27).

God is giving you these days for a reason: to make your peace with Him. God loves you, and Christ died to take away your sins. More than that, He rose again from the dead to give you hope for life beyond the grave. Jesus’ promise is for you: “For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life” (John 3:16). Turn to Christ and give your life to Him today.

Lacey Sturm, former lead singer of “Flyleaf,” was ready to kill herself at 16. She searched for something—anything—to fill her life, but kept coming up empty.

Aging brains aren’t necessarily declining brains

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For years, conventional wisdom held that growing older tends to be bad news for brains. Past behavioral data largely pointed to loss in cognitive – that is, thinking – abilities with age, including poorer memory and greater distractibility. Physical measures of brain structure also showed atrophy, or loss of volume, in many regions with age.

Watching older brains at work

Enter cognitive neuroscience, a subfield of psychology that incorporates methods from neuroscience. It uses measures of activity to understand human thought. The emphasis is on how the brain shapes behavior, asking questions like which help us form accurate memories or what area controls face perception.

Using cognitive neuroscience methods to study aging has unexpectedly revealed that, contrary to previous thought, aging brains remain somewhat malleable and plastic. Plasticity refers to the ability to flexibly recruit different areas of the brain to do different jobs. In contrast to the earlier, largely pessimistic view of aging, neuroimaging studies suggest aging brains can reorganize and change, and not necessarily for the worse.

Researchers investigate which parts of the brain are engaged during different tasks using methods such as functional magnetic resonance imaging, which measures blood flow to various areas of the brain while active. By tracking what happens inside the brain during particular activities, neuroimaging data reveal patterns of change with age. For instance, sometimes use a region in both the left and right hemispheres of their brains to perform certain tasks, while young adults engage the region in only one half of the brain. Older adults also appear to activate more anterior regions of the brain whereas young adults exhibit more posterior activation.

The emergence of the of aging occurred alongside advances in the understanding of neurogenesis; neuroscientists discovered that the growth of new neurons could continue throughout life, not just when we are very young. It is still unknown to what extent new neurons contribute to behavioral and with age. But there is some evidence in rodents that new learning and enriched, stimulating environments increase survival of new neurons potentially allowing the new neurons to contribute to abilities and even improve health.

External stimulation

One exciting new direction for research on the aging brain uses neurostimulation to temporarily activate or suppress distinct neural regions. With , a coil is held over a participant’s head. Participants may be able to feel some stimulation on the scalp when the coil is turned on. Transcranial direct current stimulation is an even more surprising technique, with current administered from a 9V battery. These methods are non-invasive, simply involving holding a device over a person’s head or attaching electrodes to the scalp, and are quite safe when operated within guidelines.

fMRI scan shows areas of brain more active than others. Credit: John Graner, Walter Reed National Military Medical Center

They allow us, for the first time, to manipulate in a healthy, functioning person. Other neuroscience methods allow neurons to be turned on or turned off using pharmacological, genetic, or other methods, but such manipulations can’t ethically be applied to humans. While neuroimaging methods allow us to view which brain regions are active while performing cognitive tasks, we haven’t been able to test whether those brain regions cause, or are critical for, those tasks.

The ability to manipulate brain regions – temporarily and safely – allows for new types of tests that couldn’t be done before. For example, stimulating the frontal cortex – the brain region behind the forehead – can decrease errors on cognitive tests. When older adults in one study were asked to give examples of items that fit into different categories, they made mistakes under time pressure. Administering transcranial direct current stimulation decreased the number of errors committed by older adults, bringing them close to the level of performance of younger adults.

Neurostimulation offers much promise to further understanding of how the brain works in aging people, but there are many limitations. The spatial area affected by neurostimulation is not very precise as the scientist passes the coil over the subject’s head. Many regions cannot be targeted because they’re located deep within the brain, particularly problematic for studying memory. And activating some regions can cause discomfort for participants, such as twitching induced in the area of the forehead.

It’s not all downhill

Much of our understanding of aging brains has thus far focused on declining . But there is some evidence that social and emotional abilities are relatively well-preserved with age. Older adults seem to be just as good at forming impressions of others and are even better at regulating or controlling their emotions than younger adults.

Stimulating the left side of his brain generates movement in the right hand. Credit: Eric Wassermann, M.D., CC BY

This suggests that brain regions underlying these abilities may not exhibit the same downward trajectory with age as those associated with cognitive abilities; these brain areas may show different patterns of reorganization and change.

Should these abilities be better preserved with age, they could be harnessed to develop effective memory strategies. For instance, emphasizing the motivational, personal and emotional significance of information to be remembered could help older people’s memories. Much research remains to be done on these questions.

Brain workouts

Older brains’ plasticity suggests they could benefit from training programs and engaging, immersive experiences such as learning new skills like quilting or digital photography. Such a finding would have profound implications for the large population of active seniors who wish to stave off age-related cognitive decline.

Shocking results! Older subjects did almost as well as young ones when their brains were direct current stimulated. Credit: Science/AAAS, Author provided

While research is flourishing on a number of potential programs that could positively affect brain health – including physical exercise, cognitive regimens and engaged, social lifestyles – caution is warranted. For example, researchers warn there is little scientific evidence of the effectiveness of brain training software – so-called brain games – to date.

The aging brain has proven to be much more dynamic than early research would have suggested. Advances in research methods and widening the range of questions under investigation will further enhance our understanding of how the brain changes and adapts across the lifespan. With luck, this knowledge will reveal ways to harness plasticity to better support cognition as we age.

Massive geographic change may have triggered explosion of animal life .

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A new analysis of geologic history may help solve the riddle of the “Cambrian explosion,” the rapid diversification of animal life in the fossil record 530 million years ago that has puzzled scientists since the time of Charles Darwin. New research suggests a major tectonic event may be connected with the apparent burst of life that occurred 530 million years ago during the Cambrian explosion.
A new analysis from The University of Texas at Austin’s Institute for Geophysics suggests a deep oceanic gateway, shown in blue, developed between the Pacific and Iapetus oceans immediately before the Cambrian sea level rise and explosion of life in the fossil record, isolating Laurentia from the supercontinent Gondwanaland.
Credit: Ian Dalziel

A new analysis of geologic history may help solve the riddle of the “Cambrian explosion,” the rapid diversification of animal life in the fossil record 530 million years ago that has puzzled scientists since the time of Charles Darwin.A paper by Ian Dalziel of The University of Texas at Austin’s Jackson School of Geosciences, published in the November issue of Geology, a journal of the Geological Society of America, suggests a major tectonic event may have triggered the rise in sea level and other environmental changes that accompanied the apparent burst of life.

The Cambrian explosion is one of the most significant events in Earth’s 4.5-billion-year history. The surge of evolution led to the sudden appearance of almost all modern animal groups. Fossils from the Cambrian explosion document the rapid evolution of life on Earth, but its cause has been a mystery.

The sudden burst of new life is also called “Darwin’s dilemma” because it appears to contradict Charles Darwin’s hypothesis of gradual evolution by natural selection.

“At the boundary between the Precambrian and Cambrian periods, something big happened tectonically that triggered the spreading of shallow ocean water across the continents, which is clearly tied in time and space to the sudden explosion of multicellular, hard-shelled life on the planet,” said Dalziel, a research professor at the Institute for Geophysics and a professor in the Department of Geological Sciences.

Beyond the sea level rise itself, the ancient geologic and geographic changes probably led to a buildup of oxygen in the atmosphere and a change in ocean chemistry, allowing more complex life-forms to evolve, he said.

The paper is the first to integrate geological evidence from five present-day continents — North America, South America, Africa, Australia and Antarctica — in addressing paleogeography at that critical time.

Dalziel proposes that present-day North America was still attached to the southern continents until sometime into the Cambrian period. Current reconstructions of the globe’s geography during the early Cambrian show the ancient continent of Laurentia — the ancestral core of North America — as already having separated from the supercontinent Gondwanaland.

In contrast, Dalziel suggests the development of a deep oceanic gateway between the Pacific and Iapetus (ancestral Atlantic) oceans isolated Laurentia in the early Cambrian, a geographic makeover that immediately preceded the global sea level rise and apparent explosion of life.

“The reason people didn’t make this connection before was because they hadn’t looked at all the rock records on the different present-day continents,” he said.

The rock record in Antarctica, for example, comes from the very remote Ellsworth Mountains.

“People have wondered for a long time what rifted off there, and I think it was probably North America, opening up this deep seaway,” Dalziel said. “It appears ancient North America was initially attached to Antarctica and part of South America, not to Europe and Africa, as has been widely believed.”

Although the new analysis adds to evidence suggesting a massive tectonic shift caused the seas to rise more than half a billion years ago, Dalziel said more research is needed to determine whether this new chain of paleogeographic events can truly explain the sudden rise of multicellular life in the fossil record.

“I’m not claiming this is the ultimate explanation of the Cambrian explosion,” Dalziel said. “But it may help to explain what was happening at that time.”

Story Source:

The above story is based on materials provided by University of Texas at Austin.Note: Materials may be edited for content and length.

Journal Reference:

  1. I. W. D. Dalziel. Cambrian transgression and radiation linked to an Iapetus-Pacific oceanic connection? Geology, 2014; DOI: 10.1130/G35886.1

Alcohol ‘should have calorie labels’

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Fat man

Alcohol should have a calorie content label in order to reduce obesity, according to public health doctors.

The doctors warn a large glass of wine can contain around 200 calories – the same as a doughnut.

Yet the Royal Society for Public Health says the vast majority of people are blissfully unaware.

Public Health Minister Jane Ellison said “great strides” had been made with labelling food, and that the government will look at the issue.

The drinks industry said it was open to the idea of calorie labels, but that labelling drinks with units of alcohol was more important.

The UK is one of the most obese nations in the world with about a quarter of adults classed as obese.

‘Startling’

Food already comes with calorie information, but alcohol is exempt from EU food labelling laws.

And the European Commission is considering whether drinks should also carry such information.

Research by the Royal Society for Public Health suggested the measure would be popular with British drinkers.

The RSPH’s chief executive, Shirley Cramer, told the BBC: “Quite startling really – 80% of adults have no idea what the calorie count is in anything they’re drinking and if they do think they have an idea they totally underestimate it anyway.

“It could help the nation’s waistlines as well as probably reduce alcohol consumption.”

In a small pub experiment conducted by the society, people who were told the calories content of their drink consumed 400 fewer calories in a session.

 

Weight surgery lowers diabetes risk

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Fat man

Weight loss surgery can dramatically reduce the odds of developing type 2 diabetes, according to a major study.

Doctors followed nearly 5,000 people as part of a trial to assess the health impact of the procedure.

The results, published in the Lancet Diabetes and Endocrinology journal, showed an 80% reduction in type 2 diabetes in those having surgery.

The UK NHS is considering offering the procedure to tens of thousands of people to prevent diabetes.

Obesity and type 2 diabetes are closely tied – the bigger someone is, the greater the risk of the condition.

The inability to control blood sugar levels can result in blindness, amputations and nerve damage.

Around a tenth of NHS budgets are spent on managing the condition.

Surgery

The study followed 2,167 obese adults who had weight loss – known as bariatric – surgery.

They were compared to 2,167 fellow obese people who continued as they were.

There were 38 cases of diabetes after surgery compared with 177 in people left as they were – a reduction of nearly 80%.

Around 3% of morbidly obese people develop type 2 each year, however, surgery reduced the figure to around 0.5%, which is the background figure for the whole population.

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What is bariatric surgery?

Gastric band

Bariatric surgery, also known as weight loss surgery, is used as a last resort to treat people who are dangerously obese and carrying an excessive amount of body fat.

This type of surgery is available on the NHS only to treat people with potentially life-threatening obesity when other treatments have not worked.

Around 8,000 people a year currently receive the treatment.

The two most common types of weight loss surgery are:

  • Gastric band, where a band is used to reduce the size of the stomach so a smaller amount of food is required to make someone feel full
  • Gastric bypass, where the digestive system is re-routed past most of the stomach so less food is digested to make someone feel full

 

The National Institute of Health and Care Excellence is considering a huge expansion of obesity surgery in the NHS in order to cut rates of type 2 diabetes.

Current guidance says surgery is a possible option for people with a BMI above 35 who have other health conditions.

But new draft guidelines argue much thinner people should be considered on a case by case basis and those with a BMI of 35 should automatically considered for surgery.

Diabetes UK says around 460,000 people will meet the criteria for an automatic assessment under the guidance.

But the total jumps nearer to 850,000 when those with a BMI of 30 are also considered, it says.

NICE anticipates figures in the tens of thousands. However, the surgery can cost between £3,000 and £15,000 and the move by NICE has raised concerns that the NHS will not be able to afford the treatment, even if there are savings in the longer term.

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Obesity statistics

Crowd of people
  • One in four adults in England is obese
  • A further 42% of men are classed as overweight
  • The figure for women is 32%
  • A BMI of 30-35 cuts life expectancy by up to four years
  • A BMI of 40 or more cuts life expectancy by up to 10 years
  • Obesity costs the NHS £5.1bn every year

Prof Martin Gullford, from King’s College London, told the BBC News website: “The key thing would be not only how effective is weight loss surgery but how safe is it in the long-term?

“And we need to know about the cost effectiveness of weight loss surgery and how that balances against the costs of diabetes, it does raise some complex issues.”

Simon O’Neill, the director of health intelligence at Diabetes UK, said: “This is interesting research that reinforces what we already know about weight loss being important for both preventing and managing type 2 diabetes.

“But it must be remembered that surgery carries risks and so bariatric surgery should only be considered if serious attempts to lose weight have been unsuccessful.

“Looking at the bigger picture, as a society we also need to focus more on stopping people becoming overweight, we need to look seriously at how we can make sure people are getting support to lose weight through access to the right services to encourage them to make healthy choices.”

A Solar Cell That Stores Its Own Power .

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Is it a solar cell? Or a rechargeable battery? Actually, the patent-pending device invented at The Ohio State University is both: the world’s first solar battery.

In the October 3, 2014 issue of the journal Nature Communications, the researchers report that they’ve succeeded in combining a battery and a solar cell into one hybrid device.

Credit: Yiying Wu, The Ohio State University

Key to the innovation is a mesh solar panel, which allows air to enter the battery, and a special process for transferring electrons between the solar panel and the battery electrode. Inside the device, light and oxygen enable different parts of the chemical reactions that charge the battery.

The university will license the solar battery to industry, where Yiying Wu, professor of chemistry and biochemistry at Ohio State, says it will help tame the costs of renewable energy.

“The state of the art is to use a solar panel to capture the light, and then use a cheap battery to store the energy,” Wu said. “We’ve integrated both functions into one device. Any time you can do that, you reduce cost.”

He and his students believe that their device brings down costs by 25 percent.

The invention also solves a longstanding problem in solar energy efficiency, by eliminating the loss of electricity that normally occurs when electrons have to travel between a solar cell and an external battery. Typically, only 80 percent of electrons emerging from a solar cell make it into a battery.

With this new design, light is converted to electrons inside the battery, so nearly 100 percent of the electrons are saved.

The design takes some cues from a battery previously developed by Wu and doctoral student Xiaodi Ren. They invented a high-efficiency air-powered battery that discharges by chemically reacting potassium with oxygen. The design won the $100,000 clean energy prize from the U.S. Department of Energy in 2014, and the researchers formed a technology spinoff called KAir Energy Systems, LLC to develop it.

“Basically, it’s a breathing battery,” Wu said. “It breathes in air when it discharges, and breathes out when it charges.”

For this new study, the researchers wanted to combine a solar panel with a battery similar to the KAir. The challenge was that solar cells are normally made of solid semiconductor panels, which would block air from entering the battery.

Doctoral student Mingzhe Yu designed a permeable mesh solar panel from titanium gauze, a flexible fabric upon which he grew vertical rods of titanium dioxide like blades of grass. Air passes freely through the gauze while the rods capture sunlight.

Normally, connecting a solar cell to a battery would require the use of four electrodes, the researchers explained. Their hybrid design uses only three.

The mesh solar panel forms the first electrode. Beneath, the researchers placed a thin sheet of porous carbon (the second electrode) and a lithium plate (the third electrode). Between the electrodes, they sandwiched layers of electrolyte to carry electrons back and forth.

Here’s how the solar battery works: during charging, light hits the mesh solar panel and creates electrons. Inside the battery, electrons are involved in the chemical decomposition of lithium peroxide into lithium ions and oxygen. The oxygen is released into the air, and the lithium ions are stored in the battery as lithium metal after capturing the electrons.

When the battery discharges, it chemically consumes oxygen from the air to re-form the lithium peroxide.

An iodide additive in the electrolyte acts as a “shuttle” that carries electrons, and transports them between the battery electrode and the mesh solar panel. The use of the additive represents a distinct approach on improving the battery performance and efficiency, the team said.

The mesh belongs to a class of devices called dye-sensitized solar cells, because the researchers used a red dye to tune the wavelength of light it captures.

In tests, they charged and discharged the battery repeatedly, while doctoral student Lu Ma used X-ray photoelectron spectroscopy to analyze how well the electrode materials survived — an indication of battery life.

First they used a ruthenium compound as the red dye, but since the dye was consumed in the light capture, the battery ran out of dye after eight hours of charging and discharging — too short a lifetime. So they turned to a dark red semiconductor that wouldn’t be consumed: hematite, or iron oxide — more commonly called rust.

Coating the mesh with rust enabled the battery to charge from sunlight while retaining its red color. Based on early tests, Wu and his team think that the solar battery’s lifetime will be comparable to rechargeable batteries already on the market.

The U.S. Department of Energy funds this project, which will continue as the researchers explore ways to enhance the solar battery’s performance with new materials.

 

Dengue vaccine tested on Indian adults, found safe .

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The world’s first dengue vaccine CYD-TDV has passed the crucial India test and could be available in the country as early as by the end of next year.

In an exclusive interview to TOI, the vaccine makers Sanofi Pasteur revealed that their first study of the vaccine on Indian adults (aged 18-45 years) across five sites in India — Delhi, Ludhiana, Bangalore, Pune and Kolkata found the vaccine “safe and immunogenic in Indian adults” with results comparable to other clinical studies in Asia.

The study showed that 87% of Indian adults in the trial were positive to dengue at enrolment, confirming the significant endemic nature of the vector borne disease in the country.

Sanofi also announced the results last week at the joint annual conference of Indian Society of Malaria and Other Communicable Diseases & Indian Association of Epidemiologists.

Dr Nicholas Jackson, Sanofi Pasteur’s chief of research and development for the dengue vaccine program told TOI in an exclusive interview: “We are in contact with the Indian authorities to assess the best registration pathway for our vaccine. Based on the positive results we now have from two phase III studies conducted in 10 countries across Asia, Latin America and the Caribbean, we will prepare to submit the vaccine for licensure in endemic countries in the first quarter of 2015.”


The Sanofi Pasteur vaccine research and development laboratory in Lyon, France. (Getty Images photo)

Dr Jackson added, “The Indian authorities requested us to perform a study in adults, which we did. This is highly significant as it is the first study of our vaccine in India on adults. The results will be an important part of our database as we consider additional clinical trials in India with our vaccine and the results will also play a part to support our licensure application in India.”

Dengue is a threat to nearly half of the world’s population. It is endemic in over 100 countries. One person is hospitalized every single minute with dengue.

“WHO has the target to reduce morbidity by 25% and mortality by 50% by 2020,” he said adding, “We just completed a large epidemiology study in India. Around 2,591 persons were enrolled in a community-based, cross-sectional sero-prevalence study across eight geographically distinct urban, peri-urban and rural sites in India. In children aged 5 to 10 years, our study showed that 60% of children had evidence of prior exposure to dengue.”
“At seven sites, this ranged from 58.2% to 80.1%. The highest seroprevalence was observed in Mumbai (80.1%), and lowest in Kalyani in eastern India (23.2%),” he said.


A dengue patient having treatment in ICU at a Delhi hospital. (Getty Images file photo)

In addition, Sanofi is also planning to conduct new cohort studies to further estimate the incidence of dengue disease in India.

Dr Jackson said, “This new study will be conducted in four sites from next year. We believe it is critical to understand well the burden of dengue disease in India. The results observed suggest dengue transmission intensity in these sites is comparable to other highly endemic countries of Southeast Asia and speaks to the significant burden of disease in children in India.”

Earlier CYD-TDV — the first dengue vaccine candidate to reach phase 3 clinical testing has shown 88.5% efficacy after three doses against severe disease dengue haemorrhagic fever which leads to hospitalization for over half a million people (mostly children) every year.

Once administered, the vaccine also provided 67% protection against dengue-associated hospitalization.


Aedes aegypti mosquitoes that spread dengue virus. (AFP photo)

Researchers found that the vaccine gave low protection (35%) against DENV 2 strain, but more than 75% protection against DENV 3 and 4, and 50% against DENV 1.

The vaccine was generally well tolerated.

A total of 647 serious adverse events were reported, 402 (62%) in the vaccine group and 245 (38%) in the placebo group.

Overall, the vaccine has shown moderate protection (56%) against the disease in Asian children, according to new research published in Lancet last month.

There is no licensed vaccine available to treat or prevent dengue fever and efforts to develop one have been complicated by the fact that dengue is caused by four distinct dengue viruses, and a vaccine must target all four serotypes (DENV 1-4).

Lead author Dr Maria Rosario Capeding, from the Research Institute for Tropical Medicine in the Philippines said, “Our results suggest that vaccination with CYD-TDV can reduce the incidence of symptomatic dengue infection by more than half and importantly reduced severe disease and hospitalizations. This candidate vaccine has the potential to have a significant impact on public health in view of the high disease burden in endemic countries.”


A woman covers her face as a municipal corporation worker in New Delhi fumigates the area to prevent mosquitos from breeding. (Getty Images file photo)

India alone accounted for around one-third of all infections. Of the 96 million apparent infections, Asia records 70% of the burden.

The vaccine will be a boon for India.

Scientists recently said that the number of people getting affected with dengue in India could actually be almost 300 times higher than what is officially reported by the country’s ministry of health. The conclusion was made by none other than the Indian Council of Medical Research — the government’s primary body for all medical and scientific research.

The new study published in American Journal of Tropical Medicine & Hygiene says that there are nearly 6 million more dengue cases in India than the official annual tally.

The government however says there is an annual average of 20,000 laboratory confirmed cases.

The study, led by researchers at Brandeis University’s Schneider Institute for Health Policy in Waltham, Massachusetts, the INCLEN Trust International in New Delhi and the ICMR’s Centre for Research in Medical Entomology (CRME) in Madurai calculated that dengue’s economic burden on India totals $1.11 billion annually; roughly the same amount India spends each year on its national space program.

To calculate dengue’s economic burden, the researchers found that the total direct medical cost to India was $548 million per year, or about $94.85 per patient. Given that the average dengue case lasts about two weeks that figure breaks down to $6.77 per patient per day. Dengue is therefore more expensive to treat in India than tuberculosis.