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AN ECLECTIC MIX OF SCIENCE, TECHNOLOGY, HISTORY AND THE ARTS

             

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Featured Artworks – Human Family – Maya Angelou

I note the obvious differences
in the human family.
Some of us are serious,
some thrive on comedy.

Some declare their lives are lived
as true profundity,
and others claim they really live
the real reality.

The variety of our skin tones
can confuse, bemuse, delight,
brown and pink and beige and purple,
tan and blue and white.

I’ve sailed upon the seven seas
and stopped in every land,
I’ve seen the wonders of the world
not yet one common man.

I know ten thousand women
called Jane and Mary Jane,
but I’ve not seen any two
who really were the same.

Mirror twins are different
although their features jibe,
and lovers think quite different thoughts
while lying side by side.

We love and lose in China,
we weep on England’s moors,
and laugh and moan in Guinea,
and thrive on Spanish shores.

We seek success in Finland,
are born and die in Maine.
In minor ways we differ,
in major we’re the same.

I note the obvious differences
between each sort and type,
but we are more alike, my friends,
than we are unalike.

We are more alike, my friends,
than we are unalike.

We are more alike, my friends,
than we are unalike.

Source – AllPoetry

You can listen to Maya Angelou reading this poem here:

http://www.scientificamerican.com/podcast/episode/maya-angelou-s-human-family/

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This new equation might finally unite the two biggest theories in physics

One of the most stubborn problems in physics today is the fact that our two best theories to explain the Universe – general relativity and quantum mechanics – function perfectly well on their own, but as soon as you try to combine them, the maths just doesn’t work out.

But a Stanford theoretical physicist has just come up with a new equation that suggests the key to finally connecting the two could be found in bizarre spacetime tunnels called wormholes.

The equation is deceptively simple: ER = EPR.

It’s not made up of numerical values, but instead represents the names of some key players in theoretical physics.

On the left side of the equation, the ER stands for Einstein and Nathan Rosen,and refers to a 1935 paper they wrote together describing wormholes, known technically as Einstein-Rosen bridges.

On the right side of the equation, EPR stands for Einstein, Rosen and Boris Podolsky, who co-wrote another paper that year describing quantum entanglement.

Back in 2013, physicist Leonard Susskind from Stanford University and Juan Maldacena from the Institute for Advance Study at Princeton suggested that the two papers could be describing pretty much the same thing – something that no one else in the field had previously considered, including Einstein himself. Continue reading

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This new study might actually explain the weirdness that is déjà vu

In French, déjà vu literally translates to “already seen”, and describes the phenomenon of having the strong feeling that the experience you’re having right now has already been experienced by you in the past. It’s clearly not a glitch in the Matrix, but scientists have been struggling for centuries to explain what prompts a feeling of déjà vu – and why. But now a team of neuroscientists just might have an answer.

Led by Akira O’Connor from the University of St Andrews in the UK, the team figured out how to trigger a feeling of déjà vu in a lab setting – making something that’s spontaneous, fleeting, and unpredictable a little bit easier to nail down. They did this by slightly tweaking a neat trick used by neuroscientists to implant false memories in the minds of their participants.As Jessica Hamzelou explains for New Scientist, this involves reciting a list of related words, such as bed, pillow, night, and dream, but deliberately leaving out the single, most obvious word that links them all – in this case, sleep.

The participants are later asked about all the words they were told, and more often than not, will swear they heard “sleep”, along with the others. So that’s how you implant a false memory, but it’s not quite the same thing as déjà vu. So O’Connor and his team added a step. In the first part of the experiment, where the participants were hearing the related words, the researchers asked them if they’d heard a word starting with “S”. Of course, they hadn’t, so the participants replied “No.” Later, when the participants were asked to recall all the words they’d heard, they knew from earlier that they hadn’t heard a word starting with “S”, but at the same time, the false memory of sleep had been implanted, so it somehow felt familiar.

“They report having this strange experience of déjà vu,” O’Connor told Hamzelou.Trying this technique out on 21 participants, the researchers observed what was happening in their brains as they experienced the feeling of déjà vu.Interestingly, even though the technique involved a memory exercise and the participants were given a false memory, the parts of the brain related to memory weren’t the ones that lit up in the fMRI scans.

At the International Conference on Memory in Budapest, Hungary, last month, O’Connor told his peers that during the experience of déjà vu, frontal areas of the brain associated with decision-making were activated. Source: This new study might actually explain the weirdness that is déjà vu

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Sex in Ancient Rome

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A new invisible film made from healthy corneal cells could restore vision to millions

Scientists in Australia have developed a technique for growing corneal cells on a thin layer of film in the lab, which can then be implanted into the eye to restore vision lost to corneal damage.

The method, which has so far been successfully demonstrated in animal trials, could have the potential to dramatically increase access to corneal transplants – which could change the lives of some 10 million people worldwide.

“We believe that our new treatment performs better than a donated cornea, and we hope to eventually use the patient’s own cells, reducing the risk of rejection,” says biomedical engineer Berkay Ozcelik, who led the research while at the University of Melbourne. “Further trials are required but we hope to see the treatment trialled in patients next year.” Source: A new invisible film made from healthy corneal cells could restore vision to millions

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Featured Artworks – Series of Self Portraits – William Utermohlen

When he learned in 1995 that he had Alzheimer’s disease, William Utermohlen, an American artist living in London, immediately began work on an ambitious series of self-portraits.

The artist pursued this project over an eight-year period, adapting his style to the growing limitations of his perception and motor skills and creating images that powerfully documented his experience of his illness.

The resulting body of work serves as a unique artistic, medical, and personal record of one man’s struggle with dementia. Source Daily Anatomy

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Can a computer copy your handwriting?

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Meteors

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Human Touch Detects Objects Smaller Than Bacteria

Your sense of touch is way more sophisticated than you can imagine. A new study indicates that our tactile capacity extends far beyond our visual range, allowing us to detect objects on the nanoscale. Researchers believe that the findings may inspire new developments in a wide variety of fields.

A study, published in 2013 in the Nature journal Scientific Reports, sought to appraise the human sense of touch in terms of our capacity to differentiate rough and smooth stimuli. Together with a group of psychologists, material scientists evaluated the test subjects’ ability to detect miniscule “bumps” along a smooth surface. According to lead researcher Mark Rutland of the Royal Institute of Technology in Stockholm, Sweden, the surprising findings shed new light on a traditionally overlooked faculty.

“What you’re capable of sensing and how you use your finger to sense a surface, up until recently has been a little bit of black art,” he explained to ABC Science. “There are other stimuli like heat, cold, wetness, but we’ve excluded them just to be able to focus on the topographical stuff.”

To test the hypothesis, the researchers enrolled 20 volunteers in an experiment. After being blindfolded, the participants were asked to run their index finger across 16 polymer surfaces featuring a series of tiny, parallel ridges. The height of these ridges ranged from 7 nanometers to 4.5 micrometers, and their wavelengths from 300 nanometers to 90 micrometers. For reference, a nanometer is 1×10−3 micrometer, or one thousandth of a micrometer. A micrometer is one thousandth of a millimeter, or about 0.000004 inches.

“The participants could distinguish a surface which had a 13-nanometre average amplitude from a smooth surface,” Rutland told reporters. “I was surprised and very very excited.”

The research team has every right to be excited. The nanometer is a tremendously minute unit used to measure worlds far beyond those perceived by the eye. The scale measures viral activity, unfolding chemistry, and the wavelength of light. A ribosome, for example, is about 20 nanometers in diameter. Edited from: Human Touch Detects Objects Smaller Than Bacteria: Nanoscale Sensitivity May Have Wide Industrial Application

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Experiments point toward memory chips 1,000 times faster than today’s

Silicon memory chips come in two broad types: volatile memory, such as computer RAM that loses data when the power is turned off, and nonvolatile flash technologies that store information even after we shut off our smartphones.

In general, volatile memory is much faster than nonvolatile storage, so engineers often balance speed and retention when picking the best memory for the task. That’s why slower flash is used for permanent storage. Speedy RAM, on the other hand, works with processors to store data during computations because it operates at speeds measured in nanoseconds, or billionths of a second.

Now Stanford-led research shows that an emerging memory technology, based on a new class of semiconductor materials, could deliver the best of both worlds, storing data permanently while allowing certain operations to occur up to a thousand times faster than today’s memory devices. The new approach may also be more energy efficient.

“This work is fundamental but promising,” said Aaron Lindenberg, an associate professor of materials science and engineering at Stanford and of photon science at the SLAC National Accelerator Laboratory. “A thousandfold increase in speed coupled with lower energy use suggests a path toward future memory technologies that could far outperform anything previously demonstrated.”

Lindenberg led a 19-member team, including researchers at SLAC, who detailed their experiments in Physical Review Letters.Their findings provide new insights into the experimental technology of phase-change memory. Source: Experiments point toward memory chips 1,000 times faster than today’s

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Scale of the Universe

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Glass walkway on Tianmen mountain

People walk on a sightseeing platform in Zhangjiajie, Hunan Province, China

A glass walkway opened on Tianmen mountain, part of the latest addition to China’s glass bridge craze. The 100m Coiling Dragon path is in Zhangjiajie National Forest Park in Hunan province. Source BBC

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The Screw

This pillar is found in Torcal de Antequera Natural Park, Málaga province, southeastern Spain. This is one of many impressive erosional features in the Natural Park set around the Torcal Mountains.

The rocks are Jurassic aged limestones, deposited along the edge of the Tethys seaway. Most of the limestone is high quality and oolitic – made of small, rounded pieces of limestone that formed in a shallow sea, far from land but still able to be moved around by passing waves. The rocks were later gently folded and thrust up to the surface as the Iberian Peninsula rotated and Africa began to impinge on Europe.

Once they were exposed, the layers began eroding in the typical karst fashion – limestones react with water anywhere it seeps in, dissolving the rock and taking it away. Both vertical fractures and bedding layers in these rocks served as conduits for water, leaving behind towers like this carved vertically and horizontally.

Although the area is a nature park today, in historic times these rocks were quarried as high-grade building and carving stone, including during the time of the Roman Empire. The white limestones at this site are considered to rival marble for carving stone in those times. Source EarthStory

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Brains of overweight people look 10 years older than those of lean people 

Researchers have found evidence that the brains of middle-aged, overweight people have the same amount of white matter – the connective tissue that allows the brain to communicate – as a lean person 10 years older. If confirmed, the results suggest that obesity could play a role in how fast a person’s brain ages, causing it to shrink faster than a lean person’s would.

“As our brains age, they naturally shrink in size, but it isn’t clear why people who are overweight have a greater reduction in the amount of white matter,” said one of the team, Lisa Ronan from the University of Cambridge in the UK. “We can only speculate on whether obesity might in some way cause these changes or whether obesity is a consequence of brain changes.”

The team examined the amount of white matter in 527 individuals between the ages of 20 and 87. They divided this data into groups depending on if the person was lean or overweight, based on their BMIs.Comparing the amount of white matter for each group, the researchers found that the brains of the overweight individuals were roughly 10 years older than their lean counterparts. In other words, a 50-year-old overweight person had the same amount of white matter as a 60-year-old lean person. Source: Brains of overweight people look 10 years older than those of lean people

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SPANISH TRAGEDY – AN HOMAGE TO DAVID

Thanks to Alan Mason for this interesting post.

I had a July birthday recently, near the 80 anniversary of the outbreak of the Spanish Civil War (1936 – 39) and as the occasion seems to have gone unmarked by the media, I thought about sharing a couple of stories with deskarati readers.

Like most English people, I left school with no knowledge of the Spanish Civil War, because it appeared in none of our school syllabuses; it was either too recent to be “History” and too far away to be English “Current Affairs”.


An Old Spaniard

When I left school I continued my studies at college, and needed to attend some evening classes, one of which was for GCE French. Of course, most of the class were teenagers, but there was also a Spaniard of about sixty. He spoke English with a heavy Spanish accent, and, as I discovered, he was learning to speak French with a heavy Spanish accent too. After an interval of sixty years I can still hear his gruff voice in my head.

Our French lecturer tried to make the elderly Spaniard feel included, among a crowd of English teenagers, by asking him questions, in French, about Spain. One evening the Spaniard asked the lecturer, very politely, to please not do this. Although it was fourteen years since the Civil War had ended, he still found any conversations about his country, among strangers, was just too much for him to bear.


Young David’s Story

After university, and some foreign travel, including Spain, I had become better informed about the people of Spain, and their history. Now in my thirties, I was visiting a colleague, Kay, and her husband, David, at their home. It was high summer, Wimbledon was in full swing, and Kay, a keen tennis player, was glued to the television set.

Neither David nor I was interested in tennis, so I suggested we sit in the garden, because I hoped he would tell me about his experiences during the Spanish Civil War. David began by explaining that, as a teenager, in the late 1930s he lived in London (2) and had a humdrum job in an office, as a clerk. Reports of the fighting in Spain were continually in the national newspapers. In his spare time, David had joined an organisation as a volunteer to distribute leaflets to raise money for humanitarian relief. .


The organisation began by helping with relief for Spanish families affected by the fighting (3), and then went on to arrange for orphaned Spanish children to be brought to Britain. David was helping to print and distribute leaflets. As the organisation expanded, it needed more people to handle the extra work, so it advertised for paid, full-time staff. David applied for one of the posts, and was accepted, packing in his job as a clerk, for full-time humanitarian relief work.
Continue reading

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Discovery of male-harming DNA mutation reinforces ‘mother’s curse’ hypothesis

There is new evidence that the “mother’s curse” – the possibility that moms may transmit genes to their children that harm their sons but not their daughters – holds true in animals.

Such a possibility arises because there are two independent parts of the genome in the eukaryote cells, which are found in plants and animals, and the two are locked in a “conflict-driven molecular arms race” that impacts human health and wellness. The lion’s share of the genome is located in the cell nucleus. But there is also a much smaller secondary portion located in the mitochondria.

According to the generally accepted theory, mitochondria were originally independent bacteria that developed an ability to tap highly toxic oxygen molecules as a powerful energy source. Eukaryotes lacked this capability, so some of them found a way to swallow the mitochondria’s ancestor without digesting it – converting it into an “endosymbiont,” an organism that lives within the body of another organism. Unlike the nuclear genome, which is built from a combination of father’s and mother’s genetic material, the mitochondrial genome is passed down exclusively from the mother. As a result, male offspring are an evolutionary dead end. While natural selection actively suppresses mutations in the mitochondrial DNA (mtDNA) that weaken females, there is no direct mechanism for weeding out those that weaken males: a situation that leads to the mother’s curse.

While natural selection actively suppresses mutations in the mitochondrial DNA (mtDNA) that weaken females, there is no direct mechanism for weeding out those that weaken males: the situation that makes the mother’s curse possible.

Now, a team of biologists from Vanderbilt University and the Fred Hutchinson Cancer Research Center in Seattle have discovered a mtDNA mutant in the fruit fly Drosophila melanogaster that substantiates the mother’s curse hypothesis in animals: It reduces male offspring’s fertility as they age but does not have any observable effect on female siblings.

“In the 20 years since this possibility was recognized, a few mitochondrial mutants have been reported that have deleterious effects on male offspring,” said Maulik Patel, assistant professor of biological sciences at Vanderbilt who headed the study, “but none of them convincingly showed that the mutants did not have any negative effects on the females. Our study is the first to look comprehensively for possible effects of male-harming mtDNA mutants on females and we were fortunate to find one such mutant that has a negative impact on male offspring without having, as far as we can assess, any adverse effects on the female siblings.” Source: Discovery of male-harming DNA mutation reinforces ‘mother’s curse’ hypothesis

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Scientists have just uncovered a major difference between DNA and RNA

A new study has shown for the first time that RNA – the older molecular cousin of DNA – splits apart when it tries to incorporate change, while DNA can contort itself and change its shape to compensate for any chemical damage. The research could finally explain why the blueprint of life is made from DNA and not RNA – and it could also prompt a rewrite of the textbooks.

“For something as fundamental as the double helix, it is amazing that we are discovering these basic properties so late in the game,” said lead researcher Hashim Al-Hashimi from the Duke University School of Medicine. “We need to continue to zoom in to obtain a deeper understanding regarding these basic molecules of life.”

Back in 1953, Watson and Crick first published their model of the DNA double helix, and predicted how the base pairs – A & T and G & C – fit together. You’re probably pretty familiar with that formation by now – two strands of DNA are linked up by the bonding of the base pairs, forming ladder rungs that hold together the twisted ladder of DNA. But researchers struggled to find evidence that the base pairs were bonding in the way that Watson and Crick had predicted – something they called Watson-Crick base pairs. Then in 1959, biochemist Karst Hoogsteen managed to take a picture of an A–T base pair, showing a slightly more skewed geometry, with one base rotated 180 degrees relative to the other.

Since then, researchers have observed both Watson-Crick and Hoogsteen base pairs in images of DNA. But five years ago, Al-Hashimi and the Duke team found something that had never seen before: DNA base pairs constantly morphing back and forth between Watson-Crick and the Hoogsteen bonding configurations. This adds a whole other dimension and level of flexibility to DNA’s structure.It turns out that DNA appears to be using Hoogsteen bonding when there’s a protein bond to a DNA site – or if there’s chemical damage to any of its bases – and once the damage is fixed or the protein is released, the DNA goes back to Watson-Crick bonds.

That discovery was a big deal in itself, but now the team has shown for the first time that RNA doesn’t have this ability, which could explain something that scientists have puzzled over for years: why DNA forms the blueprint for life, not RNA. So, while DNA will absorb chemical damage and adapt to work around it, RNA becomes too stiff and falls apart, making DNA the better structure to pass genetic information down between the generations.

“In DNA this modification is a form of damage, and it can readily be absorbed by flipping the base and forming a Hoogsteen base pair. In contrast, the same modification severely disrupts the double helical structure of RNA,” said one of the team, Huiqing Zhou.”

The finding will likely rewrite textbook coverage of the difference between the two purveyors of genetic information, DNA and RNA,” said a Duke University press release.  Source: Scientists have just uncovered a major difference between DNA and RNA

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Is Earthly life premature from a cosmic perspective?

The universe is 13.8 billion years old, while our planet formed just 4.5 billion years ago. Some scientists think this time gap means that life on other planets could be billions of years older than ours. However, new theoretical work suggests that present-day life is actually premature from a cosmic perspective.

“If you ask, ‘When is life most likely to emerge?’ you might naively say, ‘Now,'” says lead author Avi Loeb of the Harvard-Smithsonian Center for Astrophysics. “But we find that the chance of life grows much higher in the distant future.”

Life as we know it first became possible about 30 million years after the Big Bang, when the first stars seeded the cosmos with the necessary elements like carbon and oxygen. Life will end 10 trillion years from now when the last stars fade away and die. Loeb and his colleagues considered the relative likelihood of life between those two boundaries.

The dominant factor proved to be the lifetimes of stars. The higher a star’s mass, the shorter its lifetime. Stars larger than about three times the sun’s mass will expire before life has a chance to evolve. Conversely, the smallest stars weigh less than 10 percent as much as the Sun. They will glow for 10 trillion years, giving life ample time to emerge on any planets they host. As a result, the probability of life grows over time. In fact, chances of life are 1000 times higher in the distant future than now.

“So then you may ask, why aren’t we living in the future next to a low-mass star?” says Loeb. “One possibility is we’re premature. Another possibility is that the environment around a low-mass star is hazardous to life.”

Although low-mass, red dwarf stars live for a long time, they also pose unique threats. In their youth they emit strong flares and ultraviolet radiation that could strip the atmosphere from any rocky world in the habitable zone. To determine which possibility is correct—our premature existence or the hazard of low-mass stars—Loeb recommends studying nearby red dwarf stars and their planets for signs of habitability. Future space missions like the Transiting Exoplanet Survey Satellite and James Webb Space Telescope should help to answer these questions.

The paper describing this work has been accepted for publication in the Journal of Cosmology and Astroparticle Physics and is available online. Its co-authors are Avi Loeb (Harvard-Smithsonian Center for Astrophysics) and Rafael Batista and David Sloan (University of Oxford). Loeb simultaneously wrote an extended review on the habitability of the universe as a chapter for a forthcoming book. Source: Is Earthly life premature from a cosmic perspective?

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American leaps from a plane without a parachute

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A physicist has a new hypothesis to explain the LHC’s mysterious results

Since March, physicists around the world have been getting cautiously excited about a series of strange flashes of energy detected by CERN’s Large Hadron Collider (LHC). Nothing is verified, but the results suggest that we’re on the verge of finding the first particle outside the standard model of physics – the best set of equations we currently have to explain how the Universe works.

We’re still waiting for more evidence from the LHC’s latest run, but this new particle is generally predicted to be a subatomic particle with a mass six times heavier than the legendary Higgs boson.

But a physicist from the University of Kansas has presented a slightly different hypothesis to explain the strange LHC results – known as the 750 GeV (giga-electron volts) excess.

Source: A physicist has a new hypothesis to explain the LHC’s mysterious results

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