Tag: easier (page 2 of 8)

What happens to your body when you give up sugar?





Excerpt from independent.co.uk
By Jordan Gaines Lewis


In neuroscience, food is something we call a “natural reward.” In order for us to survive as a species, things like eating, having sex and nurturing others must be pleasurable to the brain so that these behaviours are reinforced and repeated.
Evolution has resulted in the mesolimbic pathway, a brain system that deciphers these natural rewards for us. When we do something pleasurable, a bundle of neurons called the ventral tegmental area uses the neurotransmitter dopamine to signal to a part of the brain called the nucleus accumbens. The connection between the nucleus accumbens and our prefrontal cortex dictates our motor movement, such as deciding whether or not to taking another bite of that delicious chocolate cake. The prefrontal cortex also activates hormones that tell our body: “Hey, this cake is really good. And I’m going to remember that for the future.”
Not all foods are equally rewarding, of course. Most of us prefer sweets over sour and bitter foods because, evolutionarily, our mesolimbic pathway reinforces that sweet things provide a healthy source of carbohydrates for our bodies. When our ancestors went scavenging for berries, for example, sour meant “not yet ripe,” while bitter meant “alert – poison!”
Fruit is one thing, but modern diets have taken on a life of their own. A decade ago, it was estimated that the average American consumed 22 teaspoons of added sugar per day, amounting to an extra 350 calories; it may well have risen since then. A few months ago, one expert suggested that the average Briton consumes 238 teaspoons of sugar each week.
Today, with convenience more important than ever in our food selections, it’s almost impossible to come across processed and prepared foods that don’t have added sugars for flavour, preservation, or both.
These added sugars are sneaky – and unbeknown to many of us, we’ve become hooked. In ways that drugs of abuse – such as nicotine, cocaine and heroin – hijack the brain’s reward pathway and make users dependent, increasing neuro-chemical and behavioural evidence suggests that sugar is addictive in the same way, too.

Sugar addiction is real

Anyone who knows me also knows that I have a huge sweet tooth. I always have. My friend and fellow graduate student Andrew is equally afflicted, and living in Hershey, Pennsylvania – the “Chocolate Capital of the World” – doesn’t help either of us. But Andrew is braver than I am. Last year, he gave up sweets for Lent. “The first few days are a little rough,” Andrew told me. “It almost feels like you’re detoxing from drugs. I found myself eating a lot of carbs to compensate for the lack of sugar.”
There are four major components of addiction: bingeing, withdrawal, craving, and cross-sensitisation (the notion that one addictive substance predisposes someone to becoming addicted to another). All of these components have been observed in animal models of addiction – for sugar, as well as drugs of abuse.
A typical experiment goes like this: rats are deprived of food for 12 hours each day, then given 12 hours of access to a sugary solution and regular chow. After a month of following this daily pattern, rats display behaviours similar to those on drugs of abuse. They’ll binge on the sugar solution in a short period of time, much more than their regular food. They also show signs of anxiety and depression during the food deprivation period. Many sugar-treated rats who are later exposed to drugs, such as cocaine and opiates, demonstrate dependent behaviours towards the drugs compared to rats who did not consume sugar beforehand.
Like drugs, sugar spikes dopamine release in the nucleus accumbens. Over the long term, regular sugar consumption actually changes the gene expression and availability of dopamine receptors in both the midbrain and frontal cortex. Specifically, sugar increases the concentration of a type of excitatory receptor called D1, but decreases another receptor type called D2, which is inhibitory. Regular sugar consumption also inhibits the action of the dopamine transporter, a protein which pumps dopamine out of the synapse and back into the neuron after firing.
In short, this means that repeated access to sugar over time leads to prolonged dopamine signalling, greater excitation of the brain’s reward pathways and a need for even more sugar to activate all of the midbrain dopamine receptors like before. The brain becomes tolerant to sugar – and more is needed to attain the same “sugar high.”

Sugar withdrawal is also real

Although these studies were conducted in rodents, it’s not far-fetched to say that the same primitive processes are occurring in the human brain, too. “The cravings never stopped, [but that was] probably psychological,” Andrew told me. “But it got easier after the first week or so.”
In a 2002 study by Carlo Colantuoni and colleagues of Princeton University, rats who had undergone a typical sugar dependence protocol then underwent “sugar withdrawal.” This was facilitated by either food deprivation or treatment with naloxone, a drug used for treating opiate addiction which binds to receptors in the brain’s reward system. Both withdrawal methods led to physical problems, including teeth chattering, paw tremors, and head shaking. Naloxone treatment also appeared to make the rats more anxious, as they spent less time on an elevated apparatus that lacked walls on either side.
Similar withdrawal experiments by others also report behaviour similar to depression in tasks such as the forced swim test. Rats in sugar withdrawal are more likely to show passive behaviours (like floating) than active behaviours (like trying to escape) when placed in water, suggesting feelings of helplessness.
A new study published by Victor Mangabeira and colleagues in this month’s Physiology & Behavior reports that sugar withdrawal is also linked to impulsive behaviour. Initially, rats were trained to receive water by pushing a lever. After training, the animals returned to their home cages and had access to a sugar solution and water, or just water alone. After 30 days, when rats were again given the opportunity to press a lever for water, those who had become dependent on sugar pressed the lever significantly more times than control animals, suggesting impulsive behaviour.
These are extreme experiments, of course. We humans aren’t depriving ourselves of food for 12 hours and then allowing ourselves to binge on soda and doughnuts at the end of the day. But these rodent studies certainly give us insight into the neuro-chemical underpinnings of sugar dependence, withdrawal, and behaviour.
Through decades of diet programmes and best-selling books, we’ve toyed with the notion of “sugar addiction” for a long time. There are accounts of those in “sugar withdrawal” describing food cravings, which can trigger relapse and impulsive eating. There are also countless articles and books about the boundless energy and new-found happiness in those who have sworn off sugar for good. But despite the ubiquity of sugar in our diets, the notion of sugar addiction is still a rather taboo topic.
Are you still motivated to give up sugar? You might wonder how long it will take until you’re free of cravings and side-effects, but there’s no answer – everyone is different and no human studies have been done on this. But after 40 days, it’s clear that Andrew had overcome the worst, likely even reversing some of his altered dopamine signalling. “I remember eating my first sweet and thinking it was too sweet,” he said. “I had to rebuild my tolerance.”
And as regulars of a local bakery in Hershey – I can assure you, readers, that he has done just that.
Jordan Gaines Lewis is a Neuroscience Doctoral Candidate at Penn State College of Medicine

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Windwheel concept combines tourist attraction with "silent turbine"


 The Dutch Windwheel concept is designed to be part energy icon, part tourist attraction an...


Excerpt from gizmag.com
By Stu Robarts


The Dutch have long used windmills to harness wind energy. A new concept proposed for city of Rotterdam, however, is surely one of the most elaborate windmills ever conceived. The Dutch Windwheel is a huge circular wind energy converter that houses apartments, a hotel and a giant coaster ride.

The concept is designed to be part energy icon, part tourist attraction and part residential building. It is a 174-m (571-ft) structure comprising two huge rings that appear to lean against each other. "We wanted to combine a big attraction for Rotterdam with a state-of-the-art sustainable concept," explains Lennart Graaff of the Dutch Windwheel Corporation, to Gizmag.

The larger outer ring houses 40 pods on rails that move around the ring and provide those who visit with views of Rotterdam and its port. The smaller inner ring, meanwhile, houses 72 apartments, a 160-room hotel across seven floors and a panoramic restaurant and viewing gallery. Perhaps most remarkable feature of of all, however, is a huge "bladeless turbine" that spans the center smaller ring.

Although this may look and sound like some of the more out-there architectural concepts that Gizmag has featured, it is actually based on existing (albeit prototypical) technology. The electrostatic wind energy convertor (EWICON) was developed at Delft Technical University and generates electricity by harnessing the movement of charged water droplets in the wind. Its lack of moving parts makes it noiseless and easier to maintain than traditional turbines.

Dhiradj Djairam, of the TU Delft team that developed the EWICON, tells Gizmag that the Dutch Windwheel Corporation has expressed "a serious interest" in the technology. Djairam says he has provided an explanation of the technology to the organization and provided a rough outline for a realistic research and development program. To date, only small-scale research projects have been carried out, with additional funding opportunities being explored.

The Dutch Windwheel concept is 174 m (571 ft) tall and has underwater foundations

The Dutch Windwheel concept has other sustainable aspects, too. Photovoltaic thermal hybrid panels would be used to contribute to the generation of electricity, and rainwater would be collected for use in the building. The Dutch Windwheel Corporation says the building itself is designed to be built with locally-sourced materials, and in such a way as it could ultimately be disassembled and re-used elsewhere.

Among the other features of the design are space for commercial functions in the structure's plinth, and foundations that are underwater, making it it look as though the structure is floating. 

We're told that the amount of power the Dutch Windwheel will require to run – and be able to generate – is not yet clear. Likewise, the final technologies and additional sustainability features that would be present in the building have yet to be finalized...

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What Would It Be Like to Live on Mercury?


Mercury With Subtle Colors
Mercury's extreme temperatures and lack of an atmosphere would make it very difficult, if not impossible, for people to live on the planet. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington


Excerpt from  space.com
By Joseph Castro, Space.com Contributor


Have you ever wondered what it might be like to homestead on Mars or walk on the moons of Saturn? So did we. This is the first in Space.com's 12-part series on what it might be like to live on or near planets in our solar system, and beyond. Check back each week for the next space destination.
With its extreme temperature fluctuations, Mercury is not likely a planet that humans would ever want to colonize. But if we had the technology to survive on the planet closest to the sun, what would it be like to live there?

To date, only two spacecraft have visited Mercury. The first, Mariner 10, conducted a series of Mercury flybys in 1974, but the spacecraft only saw the lit half of the planet. NASA's MESSENGER spacecraft, on the other hand, conducted flybys and then entered Mercury's orbit — in March of 2013, images from the spacecraft allowed scientists to completely map the planet for the first time.



MESSENGER photos of Mercury show that the planet has water ice at its poles, which sit in permanent darkness. Mining this ice would be a good way to live off the land, but setting up bases at the poles might not be a good idea, said David Blewett, a participating scientist with the Messenger program.

"The polar regions would give you some respite from the strength of the sun on Mercury," Blewett told Space.com. "But, of course, it's really cold in those permanently shadowed areas where the ice is, and that presents its own challenge."

A better option, he said, would probably be to set up a home base not far from one of the ice caps, perhaps on a crater rim, and have a water mining operation at the pole.

Still, dealing with extreme temperatures on Mercury would likely be unavoidable: Daytime temperatures on the planet can reach 800 degrees Fahrenheit (430 degrees Celsius), while nighttime temperatures can drop down to minus 290 degrees Fahrenheit (minus 180 degrees Celsius).

Scientists once believed Mercury was tidally locked with the sun, meaning that one side of the planet always faces the sun because it takes the same amount of time to rotate around its axis as it does to revolve around the star. But we now know that Mercury's day lasts almost 59 Earth days and its year stretches for about 88 Earth days.

Interestingly, the sun has an odd path through the planet's sky over the course of Mercury's long day, because of the interaction between Mercury's spin rate and its highly elliptical orbit around the sun.

"It [the sun] rises in the east and moves across the sky, and then it pauses and moves backwards just a tad. It then resumes its motion towards the west and sunset," said Blewett, adding that the sun appears 2.5 times larger in Mercury's sky than it does in Earth's sky.

And during the day, Mercury's sky would appear black, not blue, because the planet has virtually no atmosphere to scatter the sun's light. "Here on Earth at sea level, the molecules of air are colliding billions of times per second," Blewett said. "But on Mercury, the atmosphere, or 'exosphere,' is so very rarefied that the atoms essentially never collide with other exosphere atoms." This lack of atmosphere also means that the stars wouldn't twinkle at night.



Without an atmosphere, Mercury doesn't have any weather; so while living on the planet, you wouldn't have to worry about devastating storms. And since the planet has no bodies of liquid water or active volcanoes, you'd be safe from tsunamis and eruptions.

But Mercury isn't devoid of natural disasters. "The surface is exposed to impacts of all sizes," Blewett said. It also may suffer from earthquakes due to compressive forces that are shrinking the planet (unlike Earth, Mercury doesn't have tectonic activity).

Mercury is about two-fifths the size of Earth, with a similar gravity to Mars, or about 38 percent of Earth's gravity. This means that you could jump three times as high on Mercury, and heavy objects would be easier to pick up, Blewett said. However, everything would still have the same mass and inertia, so you could be knocked over if someone threw a heavy object at you, he added.

Finally, you can forget about a smooth Skype call home: It takes at least 5 minutes for signals from Mercury to reach Earth, and vice versa.

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Why science is so hard to believe?

 
In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked.


Excerpt from 


There’s a scene in Stanley Kubrick’s comic masterpiece “Dr. Strangelove” in which Jack D. Ripper, an American general who’s gone rogue and ordered a nuclear attack on the Soviet Union, unspools his paranoid worldview — and the explanation for why he drinks “only distilled water, or rainwater, and only pure grain alcohol” — to Lionel Mandrake, a dizzy-with-anxiety group captain in the Royal Air Force.
Ripper: “Have you ever heard of a thing called fluoridation? Fluoridation of water?”
Mandrake: “Ah, yes, I have heard of that, Jack. Yes, yes.”Ripper: “Well, do you know what it is?”
Mandrake: “No. No, I don’t know what it is, no.”
Ripper: “Do you realize that fluoridation is the most monstrously conceived and dangerous communist plot we have ever had to face?” 

The movie came out in 1964, by which time the health benefits of fluoridation had been thoroughly established and anti-fluoridation conspiracy theories could be the stuff of comedy. Yet half a century later, fluoridation continues to incite fear and paranoia. In 2013, citizens in Portland, Ore., one of only a few major American cities that don’t fluoridate, blocked a plan by local officials to do so. Opponents didn’t like the idea of the government adding “chemicals” to their water. They claimed that fluoride could be harmful to human health.

Actually fluoride is a natural mineral that, in the weak concentrations used in public drinking-water systems, hardens tooth enamel and prevents tooth decay — a cheap and safe way to improve dental health for everyone, rich or poor, conscientious brushers or not. That’s the scientific and medical consensus.
To which some people in Portland, echoing anti-fluoridation activists around the world, reply: We don’t believe you.
We live in an age when all manner of scientific knowledge — from the safety of fluoride and vaccines to the reality of climate change — faces organized and often furious opposition. Empowered by their own sources of information and their own interpretations of research, doubters have declared war on the consensus of experts. There are so many of these controversies these days, you’d think a diabolical agency had put something in the water to make people argumentative.
Science doubt has become a pop-culture meme. In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked.


The debate about mandated vaccinations has the political world talking. A spike in measles cases nationwide has President Obama, lawmakers and even potential 2016 candidates weighing in on the vaccine controversy. (Pamela Kirkland/The Washington Post)
In a sense this is not surprising. Our lives are permeated by science and technology as never before. For many of us this new world is wondrous, comfortable and rich in rewards — but also more complicated and sometimes unnerving. We now face risks we can’t easily analyze.
We’re asked to accept, for example, that it’s safe to eat food containing genetically modified organisms (GMOs) because, the experts point out, there’s no evidence that it isn’t and no reason to believe that altering genes precisely in a lab is more dangerous than altering them wholesale through traditional breeding. But to some people, the very idea of transferring genes between species conjures up mad scientists running amok — and so, two centuries after Mary Shelley wrote “Frankenstein,” they talk about Frankenfood.
The world crackles with real and imaginary hazards, and distinguishing the former from the latter isn’t easy. Should we be afraid that the Ebola virus, which is spread only by direct contact with bodily fluids, will mutate into an airborne super-plague? The scientific consensus says that’s extremely unlikely: No virus has ever been observed to completely change its mode of transmission in humans, and there’s zero evidence that the latest strain of Ebola is any different. But Google “airborne Ebola” and you’ll enter a dystopia where this virus has almost supernatural powers, including the power to kill us all.
In this bewildering world we have to decide what to believe and how to act on that. In principle, that’s what science is for. “Science is not a body of facts,” says geophysicist Marcia McNutt, who once headed the U.S. Geological Survey and is now editor of Science, the prestigious journal. “Science is a method for deciding whether what we choose to believe has a basis in the laws of nature or not.”
The scientific method leads us to truths that are less than self-evident, often mind-blowing and sometimes hard to swallow. In the early 17th century, when Galileo claimed that the Earth spins on its axis and orbits the sun, he wasn’t just rejecting church doctrine. He was asking people to believe something that defied common sense — because it sure looks like the sun’s going around the Earth, and you can’t feel the Earth spinning. Galileo was put on trial and forced to recant. Two centuries later, Charles Darwin escaped that fate. But his idea that all life on Earth evolved from a primordial ancestor and that we humans are distant cousins of apes, whales and even deep-sea mollusks is still a big ask for a lot of people.
Even when we intellectually accept these precepts of science, we subconsciously cling to our intuitions — what researchers call our naive beliefs. A study by Andrew Shtulman of Occidental College showed that even students with an advanced science education had a hitch in their mental gait when asked to affirm or deny that humans are descended from sea animals and that the Earth goes around the sun. Both truths are counterintuitive. The students, even those who correctly marked “true,” were slower to answer those questions than questions about whether humans are descended from tree-dwelling creatures (also true but easier to grasp) and whether the moon goes around the Earth (also true but intuitive).
Shtulman’s research indicates that as we become scientifically literate, we repress our naive beliefs but never eliminate them entirely. They nest in our brains, chirping at us as we try to make sense of the world.
Most of us do that by relying on personal experience and anecdotes, on stories rather than statistics. We might get a prostate-specific antigen test, even though it’s no longer generally recommended, because it caught a close friend’s cancer — and we pay less attention to statistical evidence, painstakingly compiled through multiple studies, showing that the test rarely saves lives but triggers many unnecessary surgeries. Or we hear about a cluster of cancer cases in a town with a hazardous-waste dump, and we assume that pollution caused the cancers. Of course, just because two things happened together doesn’t mean one caused the other, and just because events are clustered doesn’t mean they’re not random. Yet we have trouble digesting randomness; our brains crave pattern and meaning.
Even for scientists, the scientific method is a hard discipline. They, too, are vulnerable to confirmation bias — the tendency to look for and see only evidence that confirms what they already believe. But unlike the rest of us, they submit their ideas to formal peer review before publishing them. Once the results are published, if they’re important enough, other scientists will try to reproduce them — and, being congenitally skeptical and competitive, will be very happy to announce that they don’t hold up. Scientific results are always provisional, susceptible to being overturned by some future experiment or observation. Scientists rarely proclaim an absolute truth or an absolute certainty. Uncertainty is inevitable at the frontiers of knowledge.
That provisional quality of science is another thing a lot of people have trouble with. To some climate-change skeptics, for example, the fact that a few scientists in the 1970s were worried (quite reasonably, it seemed at the time) about the possibility of a coming ice age is enough to discredit what is now the consensus of the world’s scientists: The planet’s surface temperature has risen by about 1.5 degrees Fahrenheit in the past 130 years, and human actions, including the burning of fossil fuels, are extremely likely to have been the dominant cause since the mid-20th century.
It’s clear that organizations funded in part by the fossil-fuel industry have deliberately tried to undermine the public’s understanding of the scientific consensus by promoting a few skeptics. The news media gives abundant attention to such mavericks, naysayers, professional controversialists and table thumpers. The media would also have you believe that science is full of shocking discoveries made by lone geniuses. Not so. The (boring) truth is that science usually advances incrementally, through the steady accretion of data and insights gathered by many people over many years. So it has with the consensus on climate change. That’s not about to go poof with the next thermometer reading.
But industry PR, however misleading, isn’t enough to explain why so many people reject the scientific consensus on global warming.
The “science communication problem,” as it’s blandly called by the scientists who study it, has yielded abundant new research into how people decide what to believe — and why they so often don’t accept the expert consensus. It’s not that they can’t grasp it, according to Dan Kahan of Yale University. In one study he asked 1,540 Americans, a representative sample, to rate the threat of climate change on a scale of zero to 10. Then he correlated that with the subjects’ science literacy. He found that higher literacy was associated with stronger views — at both ends of the spectrum. Science literacy promoted polarization on climate, not consensus. According to Kahan, that’s because people tend to use scientific knowledge to reinforce their worldviews.
Americans fall into two basic camps, Kahan says. Those with a more “egalitarian” and “communitarian” mind-set are generally suspicious of industry and apt to think it’s up to something dangerous that calls for government regulation; they’re likely to see the risks of climate change. In contrast, people with a “hierarchical” and “individualistic” mind-set respect leaders of industry and don’t like government interfering in their affairs; they’re apt to reject warnings about climate change, because they know what accepting them could lead to — some kind of tax or regulation to limit emissions.
In the United States, climate change has become a litmus test that identifies you as belonging to one or the other of these two antagonistic tribes. When we argue about it, Kahan says, we’re actually arguing about who we are, what our crowd is. We’re thinking: People like us believe this. People like that do not believe this.
Science appeals to our rational brain, but our beliefs are motivated largely by emotion, and the biggest motivation is remaining tight with our peers. “We’re all in high school. We’ve never left high school,” says Marcia McNutt. “People still have a need to fit in, and that need to fit in is so strong that local values and local opinions are always trumping science. And they will continue to trump science, especially when there is no clear downside to ignoring science.”
Meanwhile the Internet makes it easier than ever for science doubters to find their own information and experts. Gone are the days when a small number of powerful institutions — elite universities, encyclopedias and major news organizations — served as gatekeepers of scientific information. The Internet has democratized it, which is a good thing. But along with cable TV, the Web has also made it possible to live in a “filter bubble” that lets in only the information with which you already agree.
How to penetrate the bubble? How to convert science skeptics? Throwing more facts at them doesn’t help. Liz Neeley, who helps train scientists to be better communicators at an organization called Compass, says people need to hear from believers they can trust, who share their fundamental values. She has personal experience with this. Her father is a climate-change skeptic and gets most of his information on the issue from conservative media. In exasperation she finally confronted him: “Do you believe them or me?” She told him she believes the scientists who research climate change and knows many of them personally. “If you think I’m wrong,” she said, “then you’re telling me that you don’t trust me.” Her father’s stance on the issue softened. But it wasn’t the facts that did it.
If you’re a rationalist, there’s something a little dispiriting about all this. In Kahan’s descriptions of how we decide what to believe, what we decide sometimes sounds almost incidental. Those of us in the science-communication business are as tribal as anyone else, he told me. We believe in scientific ideas not because we have truly evaluated all the evidence but because we feel an affinity for the scientific community. When I mentioned to Kahan that I fully accept evolution, he said: “Believing in evolution is just a description about you. It’s not an account of how you reason.”
Maybe — except that evolution is real. Biology is incomprehensible without it. There aren’t really two sides to all these issues. Climate change is happening. Vaccines save lives. Being right does matter — and the science tribe has a long track record of getting things right in the end. Modern society is built on things it got right.
Doubting science also has consequences, as seen in recent weeks with the measles outbreak that began in California. The people who believe that vaccines cause autism — often well educated and affluent, by the way — are undermining “herd immunity” to such diseases as whooping cough and measles. The anti-vaccine movement has been going strong since a prestigious British medical journal, the Lancet, published a study in 1998 linking a common vaccine to autism. The journal later retracted the study, which was thoroughly discredited. But the notion of a vaccine-autism connection has been endorsed by celebrities and reinforced through the usual Internet filters. (Anti-vaccine activist and actress Jenny McCarthy famously said on “The Oprah Winfrey Show,” “The University of Google is where I got my degree from.”)
In the climate debate, the consequences of doubt are likely to be global and enduring. Climate-change skeptics in the United States have achieved their fundamental goal of halting legislative action to combat global warming. They haven’t had to win the debate on the merits; they’ve merely had to fog the room enough to keep laws governing greenhouse gas emissions from being enacted.
Some environmental activists want scientists to emerge from their ivory towers and get more involved in the policy battles. Any scientist going that route needs to do so carefully, says Liz Neeley. “That line between science communication and advocacy is very hard to step back from,” she says. In the debate over climate change, the central allegation of the skeptics is that the science saying it’s real and a serious threat is politically tinged, driven by environmental activism and not hard data. That’s not true, and it slanders honest scientists. But the claim becomes more likely to be seen as plausible if scientists go beyond their professional expertise and begin advocating specific policies.
It’s their very detachment, what you might call the cold-bloodedness of science, that makes science the killer app. It’s the way science tells us the truth rather than what we’d like the truth to be. Scientists can be as dogmatic as anyone else — but their dogma is always wilting in the hot glare of new research. In science it’s not a sin to change your mind when the evidence demands it. For some people, the tribe is more important than the truth; for the best scientists, the truth is more important than the tribe.

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Ancient rocks show life could have flourished on Earth 3.2 billion years ago


photo of red rocks and blue sky
The oldest samples are sedimentary rocks that formed 3.2 billion years ago in
northwestern Australia. They contain chemical evidence for nitrogen
fixation by microbes.R. Buick / UW



Excerpt from
washington.edu

A spark from a lightning bolt, interstellar dust, or a subsea volcano could have triggered the very first life on Earth.
But what happened next? Life can exist without oxygen, but without plentiful nitrogen to build genes – essential to viruses, bacteria and all other organisms – life on the early Earth would have been scarce.

The ability to use atmospheric nitrogen to support more widespread life was thought to have appeared roughly 2 billion years ago. Now research from the University of Washington looking at some of the planet’s oldest rocks finds evidence that 3.2 billion years ago, life was already pulling nitrogen out of the air and converting it into a form that could support larger communities.

“People always had the idea that the really ancient biosphere was just tenuously clinging on to this inhospitable planet, and it wasn’t until the emergence of nitrogen fixation that suddenly the biosphere become large and robust and diverse,” said co-author Roger Buick, a UW professor of Earth and space sciences. “Our work shows that there was no nitrogen crisis on the early Earth, and therefore it could have supported a fairly large and diverse biosphere.”
The results were published Feb. 16 in Nature.

The authors analyzed 52 samples ranging in age from 2.75 to 3.2 billion years old, collected in South Africa and northwestern Australia. These are some of the oldest and best-preserved rocks on the planet. The rocks were formed from sediment deposited on continental margins, so are free of chemical irregularities that would occur near a subsea volcano. They also formed before the atmosphere gained oxygen, roughly 2.3 to 2.4 billion years ago, and so preserve chemical clues that have disappeared in modern rocks.

Even the oldest samples, 3.2 billion years old – three-quarters of the way back to the birth of the planet – showed chemical evidence that life was pulling nitrogen out of the air. The ratio of heavier to lighter nitrogen atoms fits the pattern of nitrogen-fixing enzymes contained in single-celled organisms, and does not match any chemical reactions that occur in the absence of life.

“Imagining that this really complicated process is so old, and has operated in the same way for 3.2 billion years, I think is fascinating,” said lead author Eva Stüeken, who did the work as part of her UW doctoral research. “It suggests that these really complicated enzymes apparently formed really early, so maybe it’s not so difficult for these enzymes to evolve.”

Genetic analysis of nitrogen-fixing enzymes have placed their origin at between 1.5 and 2.2 billion years ago.

“This is hard evidence that pushes it back a further billion years,” Buick said.

Fixing nitrogen means breaking a tenacious triple bond that holds nitrogen atoms in pairs in the atmosphere and joining a single nitrogen to a molecule that is easier for living things to use. The chemical signature of the rocks suggests that nitrogen was being broken by an enzyme based on molybdenum, the most common of the three types of nitrogen-fixing enzymes that exist now. 

Molybdenum is now abundant because oxygen reacts with rocks to wash it into the ocean, but its source on the ancient Earth – before the atmosphere contained oxygen to weather rocks – is more mysterious.

The authors hypothesize that this may be further evidence that some early life may have existed in single-celled layers on land, exhaling small amounts of oxygen that reacted with the rock to release molybdenum to the water.

“We’ll never find any direct evidence of land scum one cell thick, but this might be giving us indirect evidence that the land was inhabited,” Buick said. “Microbes could have crawled out of the ocean and lived in a slime layer on the rocks on land, even before 3.2 billion years ago.”

Future work will look at what else could have limited the growth of life on the early Earth. Stüeken has begun a UW postdoctoral position funded by NASA to look at trace metals such as zinc, copper and cobalt to see if one of them controlled the growth of ancient life.

Other co-authors are Bradley Guy at the University of Johannesburg in South Africa, who provided some samples from gold mines, and UW graduate student Matthew Koehler. The research was funded by NASA, the UW’s Virtual Planetary Laboratory, the Geological Society of America and the Agouron Institute.

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Banned TED Talk: The Science Delusion ~ Is science way off about the nature of our reality?



The following statement has been posted by Tedstaff at blog.ted.com: "After due diligence, including a survey of published scientific research and recommendations from our Science Board and our community, we have decided that Graham Hancock’s and Rupert Sheldrake’s talks from TEDxWhitechapel should be removed from distribution on the TEDx YouTube channel... All talks on the TEDxTalks channel represent the opinion of the speaker, not of TED or TEDx, but we feel a responsibility not to provide a platform for talks which appear to have crossed the line into pseudoscience.

Response to the TED Scientific Board’s Statement
Rupert Sheldrake
March 18, 2013

I would like to respond to TED’s claims that my TEDx talk “crossed the line into pseudoscience”, contains ”serious factual errors” and makes “many misleading statements.”
This discussion is taking place because the militant atheist bloggers Jerry Coyne and P.Z. Myers denounced me, and attacked TED for giving my talk a platform. I was invited to give my talk as part of a TEDx event in Whitechapel, London, called “Challenging Existing Paradigms.” That’s where the problem lies: my talk explicitly challenges the materialist belief system. It summarized some of the main themes of my recent book Science Set Free (in the UK called The Science Delusion). Unfortunately, the TED administrators have publically aligned themselves with the old paradigm of materialism, which has dominated science since the late nineteenth century.
TED say they removed my talk from their website on the advice of their Scientific Board, who also condemned Graham Hancock’s talk. Hancock and I are now facing anonymous accusations made by a body on whose authority TED relies, on whose advice they act, and behind whom they shelter, but whose names they have not revealed.
TED’s anonymous Scientific Board made three specific accusations:
Accusation 1:“he suggests that scientists reject the notion that animals have consciousness, despite the fact that it’s generally accepted that animals have some form of consciousness, and there’s much research and literature exploring the idea.”
I characterized the materialist dogma as follows: “Matter is unconscious: the whole universe is made up of unconscious matter. There’s no consciousness in stars in galaxies, in planets, in animals, in plants and there ought not to be any in us either, if this theory’s true. So a lot of the philosophy of mind over the last 100 years has been trying to prove that we are not really conscious at all.” Certainly some biologists, including myself, accept that animals are conscious. In August, 2012, a group of scientists came out with an endorsement of animal consciousness in “The Cambridge Declaration on Consciousness”. As Discovery News reported, “While it might not sound like much for scientists to declare that many nonhuman animals possess conscious states, it’s the open acknowledgement that’s the big news here.” (http://news.discovery.com/human/genetics/animals-consciousness-mammals-birds-octopus-120824.htm)
But materialist philosophers and scientists are still in the majority, and they argue that consciousness does nothing – it is either an illusion or an ”epiphenomenon” of brain activity. It might as well not exist in animals – or even in humans. That is why in the philosophy of mind, the very existence of consciousness is often called “the hard problem”.http://en.wikipedia.org/wiki/Hard_problem_of_consciousness
Accusation 2:“He also argues that scientists have ignored variations in the measurements of natural constants, using as his primary example the dogmatic assumption that a constant must be constant and uses the speed of light as example.… Physicist Sean Carroll wrote a careful rebuttal of this point.”
TED’s Scientific Board refers to a Scientific American article that makes my point very clearly: “Physicists routinely assume that quantities such as the speed of light are constant.”
In my talk I said that the published values of the speed of light dropped by about 20 km/sec between 1928 and 1945. Carroll’s “careful rebuttal” consisted of a table copied from Wikipedia showing the speed of light at different dates, with a gap between 1926 and 1950, omitting the very period I referred to. His other reference (http://micro.magnet.fsu.edu/primer/lightandcolor/speedoflight.html) does indeed give two values for the speed of light in this period, in 1928 and 1932-35, and sure enough, they were 20 and 24km/sec lower than the previous value, and 14 and 18 km/sec lower than the value from 1947 onwards.
1926: 299,798
1928: 299,778
1932-5: 299,774
1947: 299,792

In my talk I suggest how a re-examination of existing data could resolve whether large continuing variations in the Universal Gravitational Constant, G, are merely errors, as usually assumed, or whether they show correlations between different labs that might have important scientific implications hitherto ignored. Jerry Coyne and TED’s Scientific Board regard this as an exercise in pseudoscience. I think their attitude reveals a remarkable lack of curiosity.
Accusation 3:“Sheldrake claims to have “evidence” of morphic resonance in crystal formation and rat behavior. The research has never appeared in a peer-reviewed journal, despite attempts by other scientists eager to replicate the work.”
I said, “There is in fact good evidence that new compounds get easier to crystallize all around the world.” For example, turanose, a kind of sugar, was considered to be a liquid for decades, until it first crystallized in the 1920s. Thereafter it formed crystals everyehere. (Woodard and McCrone Journal of Applied Crystallography (1975). 8, 342). The American chemist C. P. Saylor, remarked it was as though “the seeds of crystallization, as dust, were carried upon the winds from end to end of the earth” (quoted by Woodard and McCrone).
The research on rat behavior I referred to was carried out at Harvard and the Universities of Melbourne and Edinburgh and was published in peer-reviewed journals, including the British Journal of Psychology and the Journal of Experimental Biology. For a fuller account and detailed references see Chapter 11 of my book Morphic Resonance (in the US) / A New Science of Life (in the UK). The relevant passage is online here: http://sciencesetfree.tumblr.com/
The TED Scientific Board refers to ”attempts by other scientists eager to replicate the work” on morphic resonance. I would be happy to work with these eager scientists if the Scientific Board can reveal who they are.
This is a good opportunity to correct an oversimplification in my talk. In relation to the dogma that mechanistic medicine is the only kind that really works, I said, “that’s why governments only fund mechanistic medicine and ignore complementary and alternative therapies.” This is true of most governments, but the US is a notable exception. The US National Center for Complementary and Alternative Medicine receives about $130 million a year, about 0.4% of the National Institutes of Health (NIH) total annual budget of $31 billion.
Obviously I could not spell out all the details of my arguments in an 18-minute talk, but TED’s claims that it contains “serious factual errors,” “many misleading statements” and that it crosses the line into “pseudoscience” are defamatory and false.

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The Best Bet for Alien Life May Be in Planetary Systems Very Different From Ours




Excerpt from wired.com


In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.

But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.

At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.

But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.

M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.

“By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.

That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.

This illustration shows Kepler-186f, the first rocky planet found in a star's habitable zone. Its star is an M dwarf.
This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf. NASA Ames/SETI Institute/JPL-Caltech


M dwarfs have another thing going for them. They’re the most common star in the galaxy, comprising an estimated 75 percent of the Milky Way’s hundreds of billions of stars. If Dressing’s estimates are right, then our galaxy could be teeming with 100 billion Earth-sized planets in their stars’ habitable zones.

To be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.
Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.

And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.

But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.

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4 Sky Events This Week: Inner Planets Dance While Saturn Dazzles


Illustration of moon pairing with star in the Virgo constellation
The moon pairs with the brightest star in the constellation Virgo on Tuesday.
Illustration by A.Fazekas, SkySafari


Excerpt from news.nationalgeographic.com

An eclipse of a volcanic moon by the king of planets, Jupiter, will thrill stargazers this week, as Earth's moon rides above the ringed world, Saturn.

Moon meets Maiden. On Tuesday, January 13, early birds will enjoy a particularly close encounter with the last quarter moon of the month and with the bright star Spica. All the action takes place in the constellation Virgo, the Maiden, halfway up the southern sky at dawn.

The 250-light-year-distant star appears only 2 degrees below the moon, a distance equal to about the width of your thumb held at arm's length.

It's amazing to realize that the light from Spica left on its journey to Earth back in 1765. That's the year that Great Britain passed the Stamp Act, the first direct tax levied on the American colonies and a prelude of the parliamentary oversteps that led to the American Revolution.

Mercury at its best. Look for faint Mercury about a half-hour after sunset on Wednesday, January 14, just above the southwestern horizon.

The innermost planet will appear at its farthest point away from the sun, a moment called the greatest elongation. Sitting 19 degrees east of the sun, it would be challenging to track down its faint point of light if it weren't for the nearby, superbright Venus.

The planetary duo will appear only 1.3 degrees apart, making the pair particularly impressive when viewed through binoculars or a small telescope. Look carefully and you may notice that Mercury appears to be a miniature version of the half-lit moon...

Illustration of Venus and Mercury in close conjunction in the southwest sky
This skychart shows Venus and Mercury in close conjunction in the southwest sky after sunset on Wednesday.
Illustration by A.Fazekas, SkySafari

Volcanic moon eclipse. Sky-watchers armed with telescopes will witness a distant eclipse of Jupiter's moon Io in the early morning hours of Friday, January 16.

At 12:27 a.m. EST, the gas giant's own shadow will glide across the tiny disk of the volcanic moon, which will be visible to the west of the planet.

Also early on Thursday night at 10:56 p.m. EST, Jupiter's massive storm, the Great Red Spot, crosses the middle of the planet's disk. Appearing as an orange-pink oval structure, this hurricane circles the planet every 12 hours or so and is three times larger than the Earth. 

Illustration of Jupiter in the late night southwest sky
This wide-angle skychart shows the location of Jupiter in the southeast sky on Thursday evening and early morning Friday. The insert telescope view shows Jupiter and location of its moon Io just before it enters the planet’s shadow.
Illustration by A.Fazekas, SkySafari
Luna and Saturn. Later on, near dawn on Friday, January 16, the waning crescent moon will appear to park itself just 2 degrees north of Lord of the Rings.

The ringed world can't be missed with the naked eye since it is the brightest object visible in the southeastern predawn sky. Its proximity to the moon will make it that much easier to identify.
Train a telescope on this yellow-tinged point of light, and it will readily reveal its stunning rings, tilted a full 25 degrees toward Earth. Currently Saturn sits nearly 994,000 miles (1.6 billion kilometers) away from Earth, which means that the reflected sunlight off its cloud tops takes 87.4 minutes to reach our eyes.
Happy hunting!

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Three Perceived Laws of Motion that are Incorrect

Newton's Three Laws of Motion are a landmark achievement in physics. They describe how all objects move. Unfortunately most people do not really understand Newton's Laws because they have pre-existing ideas about the way the world works. This film i...

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Ballistic Capture Can Send Spacecraft to Mars at Cheaper Cost

Ballistic capture could be used to reach Mars at a lower cost than current techniques. How does it work, and what are the drawbacks?Excerpt from techtimes.comBallistic capture is a navigational technique utilized by spacecraft, and has been successfu...

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First legal pot, now Colorado launches new voting experiment




Excerpt from nypost.com

As Colorado goes Election Night, so goes the nation — maybe.
The Centennial State is clearly a barometer of President Obama’s falling popularity. 

The man who began his meteoric rise as the Democratic presidential nominee in Denver’s stadium in 2008 has lost much of his luster with Colorado voters and appears to be bringing down other Democrats with him. 

Polls show Republican Cory Gardner ahead by seven points in his race to unseat incumbent Democratic Sen. Mark Udall, and GOP gubernatorial candidate Bob Beauprez is neck and neck with sitting Gov. John HIckenlooper. 

But before Republicans pop the champagne corks, it’s worth considering the big wild card in this election.

Like the rest of Colorado’s roughly 3 million registered voters, I received my ballot in the mail about two weeks ago. This year will be the first that all Colorado voters received mail ballots, even without requesting them. 

The potential for thousands more voters to cast ballots in what is usually a low-turnout midterm election could easily confound pollsters and politicos. 

Conventional wisdom is that higher turnout favors Democrats — and the odds of higher turnout helping Dems in Colorado seem somewhat greater, given the demographics of the state.
Some 14 percent of eligible voters in Colorado are Hispanic. Obama improved his share of support among Colorado Hispanic voters from 61 percent in 2008 to 75 percent in 2012. 

If mail ballots boost Hispanic voter participation by a few percentage points this year, it will likely redound to Democrats’ benefit. In a race as tight as the Colorado governor’s race, Hispanic voters could well determine the outcome.

But demographics don’t give the full picture. Since 2008, Democrats have benefited from a much stronger ground game that put operatives in the field to turn out their likely voters. 

The effort wasn’t enough to stop populist Tea Party voters from boosting GOP fortunes in the 2010
congressional races, but Colorado was the exception. Democrat Michael Bennet won an open Senate race with just 30,000 more votes than his Republican opponent, Ken Buck. 


The question in 2014 is whether mail balloting helps or erases the Democrats’ edge.

A New York Times analysis of Colorado mail ballots that had already been tallied 10 days out from the election seemed to give Republicans an advantage. Registered Republicans had mailed in ballots in higher numbers than Democrats, 42.8 percent to 32.3 percent. 

But those trends may not continue. It could be that more Republicans simply cast their ballots early, which is where the Democratic ground game will come in handy. 

Early voting makes it easier for “volunteers” — many of them paid political and union operatives — to go door to door to urge those who haven’t voted to do so.


Who is to stop “volunteers” from showing up with dozens of mail ballots collected from elderly voters or others who may have been pressured by union reps or family members to cast their votes?
Colorado will have regulations in place to limit the number of ballots a single individual can drop off at collection centers after 2015, but this year the possibility of ballot stuffing is real.

State election officials claim that the signature on the ballot envelope is their way to detect phony ballots. But the system hardly seems foolproof, requiring signatures to be scanned and matched against a database that may prove more cumbersome than anticipated.

Nov. 4 will be a test for Colorado — and for the nation — on this new experiment in democracy.

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India’s Mars mission: A Picture that Spoke 1,000 words

When the crowded command control room of India's Mars mission exploded into applause after it successfully put a satellite into orbit around the Red Planet, photographer Manjunath Kiran of the AFP news agency clicked this remarkable image of scienti...

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7 Types of Non-Believers Who Don’t Need Religion

Valerie Tarico, AlterNetReligious labels help shore up identity. So what are some of the things non-believers can call themselves?Catholic, born-again, Reformed, Jew, Muslim, Shiite, Sunni, Hindu, Sikh, Buddhist…religions give people labels. The downside can be tribalism, an assumption that insiders are better than outsiders, that they merit more compassion, integrity and generosity or even that violence toward “infidels” is acceptable. But the upside is that religious o [...]

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