Day: 08/12/2014

Laser identifies explosive powders 400 meters away .

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A lightning-fast laser lightshow could help detect explosive powders from a distance, a study in the August 11 Proceedings of the National Academy of Sciences suggests.

green laser light flash

The researchers took advantage of a physical phenomenon known asRaman scattering, in which some of the light shining on a surfaceinteracts with the material’s vibrating molecules before scattering away. The frequency of this scattered light serves as a fingerprint of the material. The researchers found they could use short pulses of green light to distinguish between explosive and inert powders from 400 meters away.

Space history made

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After travelling a distance of 6.4 billion kilometres since it was launched in March 2004, Rosetta made space history on August 6 when it became the first spacecraft to rendezvous with a comet — 67P/Churyumov-Gerasimenko, a 4.5-km-long object. The craft, which is at an altitude of about 100 km, will in the next couple of months move closer to 67P till it is about 4 km above its surface. At this altitude, the next biggest challenge will be to ensure that the lander, Philae, to be airdropped from Rosetta, lands safely on the comet. The identification of a smooth landing site to deploy the lander in November was not done in advance as little information was available about the nature of the terrain. Images collected by the craft from a distance of 285 km from the comet have suggested a ragged surface marked by “sharp-edged structures” with precipitous cliffs. It remains to be seen if the “smooth” areas seen from that height are indeed smooth when better-resolution pictures become available as the Rosetta gets closer. Unlike the Curiosity rover that is moving freely on Mars, Philae, with an array of instruments, would be anchored to the surface. Rosetta has already changed our understanding of 67P’s shape — it appears as a “double-lobed structure” with a neck connecting the two. It could have either been formed by the fusion of two comets or by differential erosion at the spot that now forms the neck.

Comets are primitive objects formed from debris left over when the Solar System was formed around 4.6 billion years ago. They retain primordial secrets — the gas, dust and organic molecules since they were created. Hence, information garnered from 67P can unlock many secrets about the birth and evolution of the Solar System and the origin of water and life on Earth. It is believed that comets had seeded Earth with water and carbon-containing molecules, particularly amino acids that are the building blocks of life. By studying materials lying 20 cm below the comet’s surface, Philae is expected to provide vital information about organic materials that are securely locked and cannot be studied from Earth. Since life on earth is comprised exclusively of left-handed amino acids, the “predominance” of such molecules in 67P would strengthen the possibility of comets’ role in seeding life on the planet of humans. Another important study is the assessment of the ratio of normal to heavy water (where one of the two normal hydrogen atoms has been replaced by the heavy hydrogen isotope deuterium) to ascertain if the comet’s ice signature matches that of water on Earth. A few years ago, the Hartley 2 comet was found to have the same signature as water; none of the other comets studied before had a similar match.

 

 

Boy has ears created from ribs

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Kieran, his family and his surgeon, before, during and after the operation

A boy who was born without ears has had a pair created from his ribs.

Nine-year-old Kieran Sorkin had the surgery at London’s Great Ormond Street Hospital.

About 100 children a year in the UK are born without one or both ears, a condition known as microtia.

Kieran was born deaf with small lobes where his ears should be. He can already hear, thanks to previous surgery to implant a hearing aid.

“I want people to stop asking me questions”, said Kieran from Hertfordshire. “I’d like just to look like my friends.

“I’d also like to be able to wear sunglasses and earphones.”

Kieran’s mum Louise Sorkin said: “He’s a very sociable boy and has longed for this operation for years.

“I don’t want children bullying him because he’s different. I just want him to be accepted like everyone else.”

On the morning of the operation, consultant plastic surgeon Neil Bulstrode stencils the shape of Louise Sorkin’s ears.

He said: “When a patient has one ear we can match the new ear to that. Fortunately Kieran’s mum has very pretty ears so that should work well.”

Psychological benefits

In theatre the surgical team remove cartilage from six of his ribs. It is cut, shaped and sewn.

ears
Kieran’s ears were shaped from cartilage taken from his ribs

These frameworks are inserted in pockets in the skin and then using suction, they take on the shape of an ear on both sides.

Great Ormond Street Hospital does about 40 of these operations each year, although most of those are to create one missing ear.

The surgery is cosmetic, not to improve hearing. But Mr Bulstrode said it brings huge psychological benefits.

“If you can change the confidence of a patient at this young age, you can change their whole trajectory in life.

“You see this when they come back. It’s a huge boost for them.”

Tissue engineering

Advances in tissue engineering mean that this kind of reconstructive surgery could be done quite differently within a decade.

Scientists at the Institute of Child Health (ICH), part of University College London, are creating stem cells from patients’ fat tissue.

The Institute, which is Great Ormond Street Hospital’s research partner, induces the cells to make cartilage or bone.

Dr Patrizia Ferretti, leader of the ICH’s Development and Regeneration Group, who is leading the study, said: “This approach would be far less invasive for a child than the current method of harvesting a child’s rib cartilage.”

Last year scientists in the US implanted a human-like ear, grown from cow and sheep cells, onto a rat.

But such research is still at its early stages, and for the foreseeable future children needing new ears will benefit from the same procedure used at Great Ormond Street Hospital.

Three days after surgery, Kieran is given a mirror to look at his new ears.

Kieran after surgery
Kieran is delighted with his new ears

His first reaction was “Wow!”. Kieran started to giggle, but the operation on his ribs means it hurts when he laughs.

Kieran will need a second operation in six months to make his ears stand out from the scalp more, but he’s already delighted with the result.

Babies ‘rapid brain growth revealed’

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Babies

Scans showed babies brains reached more than half their adult size in the first 90 days of life

Human brains grow most rapidly just after birth and reach half their adult size within three months, according to a study in JAMA Neurology.

Using advanced scanning techniques, researchers found male brains grew more quickly than those of female infants.

Areas involved in movement developed at the fastest pace. Those associated with memory grew more slowly.

Scientists say collating this data may help them identify early signs of developmental disorders such as autism.

Sizing up development

For centuries doctors have estimated brain growth using measuring tape to chart a baby’s head circumference over time.

Any changes to normal growth patterns are monitored closely as they can suggest problems with development.

But as head shapes vary, these tape measurements are not always accurate.

Led by scientists at the University of California, researchers scanned the brains of 87 healthy babies from birth to three months.

They saw the most rapid changes immediately after birth – newborn brains grew at an average rate of 1% a day. This slowed to 0.4% per day at the end of the 90-day period.

Researchers say recording the normal growth trajectory of individual parts of the brain might help them better understand how early disorders arise.

They found the cerebellum, an area of the brain involved in the control of movement, had the highest rate of growth – doubling in size over the 90-day period.

The slowest region measured was the hippocampus, a structure that plays an important part in how memories are made.

‘Accurate data’

Scientists suggest this could mirror the relative significance of these skills as a young infant.

Dr Martin Ward Platt, a consultant paediatrician at the Royal Victoria Infirmary in Newcastle, who was not involved in the research, told the BBC: “This is the first time anyone has published accurate data about how babies’ brains grow that is not based on post-mortem studies or less effective scanning methods.

“The study should provide us with useful information as this is an important time in development.

“We know, for example, if there are difficulties around the time of birth, a baby’s growth can fall away in the first few months.”

Looking at babies who were born early, researchers noticed their brains were 4% smaller than the brains of babies born at full term.

And despite growing at a quicker rate than babies born on time, their brains were still 2% smaller at the end of three months.

Scientists will now investigate whether alcohol and drug consumption during pregnancy alters brain size at birth.

Purest-ever silicon in quantum fix

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silicon production

The silicon is very hot and glows when it is collected inside a vacuum chamber

In a quantum computer, pure silicon is not enough – only one specific type of silicon atom will do.

The good stuff is silicon-28, and physicists in the US have worked out how to produce it with 40 times greater purity than ever before.

Even better, they can do it in the lab instead of relying on samples made ten years ago in a huge, repurposed plutonium plant in St Petersburg.

This promises to solve a serious supply problem in quantum computing research.

Several of the most promising schemes for building a quantum computer are based in silicon. One that has received much attention stores “qubits” in atoms of another element, like phosphorous, embedded in a tiny layer of ultra-pure silicon-28.

“Start Quote

We had an apparatus whose purpose had come to an end, and we had a problem that needed solving, and we married them up”

Dr Joshua PomeroyNational Institute of Standards and Technology, Maryland

Qubits are the quantum replacement for bits – the ones and zeros that represent information inside a conventional computer. They promise to usher in a new era of computing because they can simultaneously encode a one and a zero, enabling incredibly fast and complex calculations.

The difficulty for silicon-based designs is that normal silicon contains quite a lot of atoms that aren’t silicon-28. Almost 8% of a commercial silicon wafer is made up of other isotopes like silicon-29, which would cause interference in a quantum chip.

“It leads to decoherence, which is sort of like ADD in computers,” explained Dr Joshua Pomeroy, one of the physicists behind the new work, from the National Institute of Standards and Technology in Maryland.

Researchers in this field, like Dr Pomeroy, have been relying on off-cuts of enriched silicon-28 that all started out in Russia.

The St Petersburg facility is a repurposed plutonium enrichment plant, housing industrial-scale gas centrifuges which were commissioned in 2004, by German scientists, to produce a sample of silicon-28 with 99.99% purity.

That sample was used to crystallise 5kg of the stuff, at a cost of around one million euros, for an international effort to calculate Avogadro’s number from 1kg, perfect spheres of silicon-28.

Waste material from this project has been almost the only global source of this high-quality silicon ever since.

silicon sphere
Most of the world’s purest silicon-28 was used to make perfect 1kg spheres as part of the Avogadro project

Dr Pomeroy explained that the quantum community “can’t command the resources” to commission that type of production. “It’s fortuitous that the Avogadro project existed,” he told the BBC.

“So there’s sort of a nervousness – when they wrap up finally, and they’re not buying any more of it, what are we going to do?”

But Dr Pomeroy and his colleagues have now shown that small amounts of silicon-28, enriched to an unprecedented 99.9998%, can be produced using equipment already found in many labs.

Small but perfectly formed

They managed the feat with kit that is normally used for mass spectrometry – a technique for identifying a substance based on the weight of the different atoms it contains. By pumping ions of silicon through a big magnetic field, the different isotopes (atoms of silicon with different weights) can be separated from each other, because heavier atoms are diverted less by the magnet than lighter ones.

chamber
The equipment is normally used in mass spectrometry, which identifies substances based on their molecular weight

Dr Pomeroy said this was an unexpectedly simple solution. “We had what often happens in science, which is that we had an apparatus whose purpose had come to an end. And we had a problem that needed solving, and we married them up.”

The thin films of silicon-28 that his team can produce are very, very pure – but also very small.

“It’s much more difficult to produce large quantities,” Dr Pomeroy concedes, “but particularly in the research phase, those quantities are largely unnecessary.”

Despite some controversial commercial initiatives, quantum computers primarily remain a field of research. And according to Dr Pomeroy, the new approach is more than capable of delivering enough of the purer-than-pure silicon for scientists to test out their designs.

Importantly, researchers around the world could potentially make it in their own labs.

“We’re recognising that we don’t need to produce an entire wafer’s worth of silicon-28 that’s enriched,” he said. “We only really need to make enough to insulate the computer from the rest of the wafer.”

GM flies ‘could save crops’

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Genetically engineered fruit flies
Genetically engineered males pass on a lethal gene to wild females they mate with

A type of genetically engineered fly which eventually kills itself off could be an effective method of pest control, according to new research.

These male mutant flies have a lethal gene which interrupts female development.

They were trialled in a greenhouse resulting in “population collapse”.

If released into the wild, they could prevent damage to crops in a way that is cheap, and environmentally friendly, according to the researchers.

But others oppose the technology and say releasing genetically modified flies into the wild could have unintended consequences.

The research is published in the journal Proceedings of the Royal Society B.

The Mediterranean fruit fly is a global agricultural pest which infests over 300 crops, including wild fruit, vegetables and nuts, causing extensive damage.

Currently, techniques for pest control include sterilisation and insecticides. However, sterile flies do not mate as well in the wild as the process to make them sterile weakens them. Insecticide also poses problems as flies can quickly develop immunity.

The male GM flies produced by Oxfordshire-based biotechnology company Oxitec are only capable of producing male offspring. They have what Oxitec calls “pre-pupal female lethality”. In other words, a female specific gene kills the females before they become adults.

This means that after several generations, the flies die off as the males can no longer find mates.

Mediterranean fruit fly
The Mediterranean fruit fly is an agricultural pest for hundreds of crops around the world

In order to breed the flies in the lab, the company can “silence” the lethal gene using an antibiotic called tetracycline. This works as a chemical switch which represses the fatal gene. When the chemical is removed, females no longer survive.

“This allows you to reach thousands or millions of male insects all carrying this gene construct… Very rapidly you get a sex biased population of only male individuals, which is not sustainable,” explained lead author Philip Leftwich, from the University of East Anglia and Oxitec.

“In a local area where you perform this process, the population levels quickly shrink, massively reducing the amount of crop damage,” he told the BBC’s Science in Action programme.

The next step, he added, would be open field trials, which would need government approval.

Oxitec has already completed extensive field trials with GM mosquitoes in Brazil in order to prevent the spread of dengue fever, killing 96% of the dengue-spreading mosquitoes. They are also bidding to trial GM insects in Europe to reduce olive flies in Spain, a major pest for olive production.

Researcher releasing Oxitec mosquitoes in trials in Brazil
Oxitec is already trialling its GM mosquitoes in an effort to combat dengue fever in Brazil

Helen Wallace from Genewatch, an organisation that monitors the use of genetic technology, is critical of the work. She said that the long-term effects of releasing millions of GM flies would be impossible to predict.

She was also concerned that dead fly larvae could be left inside crops.

“Fruit grown using Oxitec’s GM flies will be contaminated with GM maggots which are genetically programmed to die inside the fruit they are supposed to be protecting.

“Contaminated fruit won’t be welcome on the market and could be bad for health. Male GM flies will survive for multiple generations and could be spread worldwide when fruit is transported.”

She added that the genetic killing mechanism was likely to fail in the longer term as the GM flies evolve resistance or breed in sites contaminated with the antibiotic tetracycline, widely used in agriculture.

Responding to concerns, Dr Leftwich said that the flies have been extensively tested with no reason to think they would have adverse effects, which the team would monitor closely.

“The nature of the modification to the flies, it’s important to stress, is it makes them disadvantageous to their local counterparts in that they can only produce sons. If we stopped releasing these individuals they would quickly be removed from the gene pool.”

How to help in an emotional crisis

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Mental health disorders are common in the United States, affecting tens of millions of Americans each year, according to theNational Institute of Mental Health. Yet only a fraction of those people receive treatment. Without treatment, mental health disorders can reach a crisis point.

How to help in an emotional crisis

Some examples of mental health crises include depression, trauma, eating disorders, alcohol or substance abuse, self-injury and suicidal thoughts. If you suspect a friend or family member is experiencing an emotional crisis, your help can make a difference.

Spotting the Signs

One of the most common signs of emotional crisis is a clear and abrupt change in behavior. Some examples include:

  • Neglect of personal hygiene.
  • Dramatic change in sleep habits, such a sleeping more often or not sleeping well.
  • Weight gain or loss.
  • Decline in performance at work or school.
  • Pronounced changes in mood, such as irritability, anger, anxiety or sadness.
  • Withdrawal from routine activities and relationships.

Sometimes, these changes happen suddenly and obviously. Events such as a natural disaster or the loss of a job can bring on a crisis in a short period of time. Often, though, behavior changes come about gradually. If something doesn’t seem right with your loved one, think back over the past few weeks or months to consider signs of change.

Don’t wait to bring up your concerns. It’s always better to intervene early, before your loved one’s emotional distress becomes an emergency situation. If you have a feeling that something is wrong, you’re probably right.

Lend an Ear

If you suspect your loved one is experiencing a mental health crisis, reaching out is the first step to providing the help he or she needs to get better. Sit down to talk in a supportive, non-judgmental way. You might start the conversation with a casual invitation: “Let’s talk. You don’t seem like yourself lately. Is there something going on?”

Stay calm, and do more listening than talking. Show your loved one that you can be trusted to lend an ear and give support without passing judgment. When discussing your concerns, stick to the facts and try not to blame or criticize.

Seek Professional Help

Reaching out can help your friend or family member begin to get a handle on an emotional crisis. But professional help is the best way to fully address a mental health problem and get that problem under control. You can explain that psychologists have specialized training that makes them experts in understanding and treating complex emotional and behavioral problems. That training is especially critical when an emotional disorder has reached crisis levels.

Psychologists use scientifically tested techniques that go beyond talking and listening. They can teach their clients tools and skills for dealing with problems, managing stress and working toward goals.

To help your loved one find a psychologist to speak with, you might encourage your loved one to speak to his or her primary care provider about available mental health resources in your community. If your workplace has an employee assistance program (EAP), that can be a useful resource and referral service. You can also find a psychologist in your area by using APA’sPsychologist Locator Service.

Concerns About Suicide or Self-Harm or Threats to Harm Others

No emotional crisis is more urgent than suicidal thoughts and behavior or threats to harm someone else. If you suspect a loved one is considering self-harm or suicide, don’t wait to intervene.

It’s a difficult topic to bring up, but discussing suicide will not put the idea in someone’s head. In fact, it’s not abnormal for a person to have briefly thought about suicide. It becomes abnormal when someone starts to see suicide as the only solution to his or her problems.

If you discover or suspect that your loved one is dwelling on thoughts of self-harm, or developing a plan, it’s an emergency. If possible, take him or her to the emergency room for urgent attention. Medical staff in the ER can help you deal with the crisis and keep your loved one safe.

If you think someone is suicidal or will harm someone else, do not leave him or her alone. If he or she will not seek help or call 911. Eliminate access to firearms or other potential tools for harm to self or others, including unsupervised access to medications.

The National Suicide Prevention Lifeline is also a valuable resource. If you’re concerned about a loved one’s mental state or personal safety, and unable to take him or her to the emergency room, you can talk to a skilled counselor by calling  1-800-273-TALK.

If you’re concerned about a loved one, don’t put it off. You can make the difference in helping your friend or family member get back on track to good mental health.

Will Kidney Stones Recur? New Test Might Tell

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They said the tool could help patients and their doctors decide whether preventive steps are needed.

The tool uses 11 questions to assess kidney stone patients’ risk of developing another kidney stone within two, five or 10 years. Characteristics associated with a higher risk include: being younger, male and white; a family history of kidney stones; blood in the urine; a kidney stone made of uric acid; having an obstructing stone in the kidney pelvis, or additional non-obstructing stones; and a past history of kidney stone-related pain from a stone that was not actually seen.

The tool was developed using data from more than 2,200 adults in Olmsted County, Minn., who experienced their first symptomatic kidney stone between 1984 and 2003. More than 700 of those people had another kidney stone by 2012.

 
  • The questionnaire, described in an article published Aug. 7 in the Journal of the American Society of Nephrology, was created by Dr. Andrew Rule, of the Mayo Clinic, and colleagues.

Kidney stones are solid pieces of material that form in a kidney because of certain substances in urine. Small stones cause little discomfort, but larger ones can get stuck in the urinary tract and cause much pain.

Nine percent of men and 6 percent of women in the United States have had a painful kidney stone. Medications and dietary changes can help prevent another kidney stone, but these preventive measures can be costly, difficult or cause side effects.

“If we knew which patients were at high risk for another symptomatic kidney stone, then we could better advise patients on whether to follow stone prevention diets or take medications,” Rule said in a journal news release.

“At the same time, patients who are at low risk of having another kidney stone may not need restrictive diets and medications,” he added.

 

5 Amazing Properties of Sunlight You’ve Never Heard About.

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Sunlight is well-known to provide us vitamin D, but did you know that it kills pain, keeps us alert at night, burns fat and more…

Our biological connection and dependence to the sun is so profound, that the very variation in human skin color from African, melanin-saturated dark skin, to the relatively melanin de-pigmented, Caucasian lighter-skin, is a byproduct of the offspring of our last common ancestor from Africa (as determined by mitochondrial DNA) migrating towards sunlight-impoverished higher latitudes, which began approximately 60,000 years ago. In order to compensate for the lower availability of sunlight, the body rapidly adjusted, essentially requiring the removal of the natural “sunscreen” melanin from the skin, which interferes with vitamin D production; vitamin D, of course, is involved in the regulation of over 2,000 genes, and therefore is more like a hormone, without which our entire genetic infrastructure becomes destabilized.

While the health benefits of vitamin D are well-documented (GreenMedInfo.com has identified over 200 health conditions that may benefit from optimizing vitamin D levels: Vitamin D Health Benefits page, and Henry Lahore’s Vitamin D Wiki has far more), the therapeutic properties of sunlight are only now being explored in greater depth by the research community.

Below are detailed five noteworthy properties of sunlight exposure:

1) Sunlight Has Pain-Killing (Analgesic) Properties

A 2005 study published in the journal Psychosomatic Medicine titled, “The effect of sunlight on postoperative analgesic medication use: a prospective study of patients undergoing spinal surgery,” analyzed patients staying on the bright side of the hospital unit who were exposed to 46% higher-intensity sunlight on average. The patients exposed to an increased intensity of sunlight experienced less perceived stress, marginally less, took 22% less analgesic medication per hour, and had 21% less pain medication costs. [i]

2) Sunlight Burns Fat

A 2011 study published in The Journal of Investigative Dermatology revealed a remarkable fact of metabolism: The exposure of human skin to UV light results in increased subcutaneous fat metabolism. While subcutaneous fat, unlike visceral fat, is not considered a risk factor for cardiovascular disease, it is known that a deficiency of one of sunlight’s best known beneficial byproducts, vitamin D, is associated with greater visceral fat.[ii] Also, there is a solid body of research showing that vitamin D deficiency is linked to obesity, with 9 such studies on our obesity research page.

One of them, titled “Association of plasma vitamin D levels with adiposity in Hispanic and African Americans,” and which was published in the journal Anticancer Research in 2005, found that vitamin D levels were inversely associated with adiposity in Hispanics and African-Americans, including abdominal obesity.[iii] The point? Exposure to UVB radiation, which is most abundant two hours on either side of solar noon and responsible for producing vitamin D, may be an essential strategy in burning fat, the natural way.

3) Sunlight via Solar Cycles May Directly Regulate Human Lifespan

Published in 2010 in the journal Medical Hypotheses and titled, “The effect of solar cycles on human lifespan in the 50 United states: variation in light affects the human genome,” researchers review the possibility that solar cycles directly affect the human genome.  According to the researchers:

In the current study we report that those persons conceived and likely born during the peaks (MAX approximately 3 years) of approximately 11-year solar cycles lived an average 1.7 years less than those conceived and likely born during non-peaks (MIN approximately 8 years). Increased energy at solar MAX, albeit relatively a small 0.1% increase from MIN, apparently modifies the human genome/epigenome and engenders changes that predispose to various diseases, thereby shortening lifespan. It is likely that same energy increases beneficial variety in the genome which may enhance adaptability in a changing environment.

Sunlight exposure, therefore, may directly affect the length of our life, and may even accelerate genetic changes that may confer a survival advantage.[iv]

4) Daytime Sunlight Exposure Improves Evening Alertness

A 2012 study published in the journal Behavioral Neuroscience titled, “Effects of prior light exposure on early evening performance, subjective sleepiness, and hormonal secretion,” found that subjects felt significantly more alert at the beginning of the evening after being exposed to 6 hours of mainly daylight exposure, whereas they became sleepier at the end of the evening after artificial light exposure.[v]

5) Sunlight May Convert To Metabolic Energy

If a novel hypothesis published in 2008 in the Journal of Alternative and Complementary Medicine is correct,[vi] a longstanding assumption that animals are incapable of utilizing light energy directly is now called into question.  In other words, our skin may contain the equivalent of melanin “solar-panels,” and it may be possible to “ingest” energy, as plants do, directly from the Sun.

Melanin has a diverse set of roles in various organisms. From the ink of the octopus, to the melanin-based protective colorings of bacteria and fungi, melanin offers protection against a variety of threats: from predators and similar biochemical threats (host defenses against invading organisms), UV light, and other chemical stresses (i.e. heavy metals and oxidizing agents). Commonly overlooked, however, is melanin’s ability to convert gamma and ultraviolet radiation into metabolic energy within living systems.

Single-celled fungi, for instance, have been observed thriving within the collapsed nuclear reactor at Chernobyl, Ukraine, using gamma radiation as a source of energy. Albino fungi, without melanin, were studied to be incapable of using gamma radiation in this way, proving that gamma rays initiate a yet-unknown process of energy production within exposed melanin.

Vertebrate animals may also convert light directly into metabolic energy through the help of melanin. In a review  titled, “Melanin directly converts light for vertebrate metabolic use: heuristic thoughts on birds, Icarus and dark human skin,” Geoffrey Goodman and Dani Bercovich offer a thought-provoking reflection on the topic, the abstract of which is well worth reading in its entirety:

Pigments serve many visually obvious animal functions (e.g. hair, skin, eyes, feathers, scales). One is ‘melanin’, unusual in an absorption across the UV-visual spectrum which is controversial. Any polymer or macro-structure of melanin monomers is ‘melanin’. Its roles derive from complex structural and physical-chemical properties e.g. semiconductor, stable radical, conductor, free radical scavenger, charge-transfer.

Clinicians and researchers are well acquainted with melanin in skin and ocular pathologies and now increasingly are with internal, melanized, pathology-associated sites not obviously subject to light radiation (e.g. brain, cochlea). At both types of sites some findings puzzle: positive and negative neuromelanin effects in Parkinsons; unexpected melanocyte action in the cochlea, in deafness; melanin reduces DNA damage, but can promote melanoma; in melanotic cells, mitochondrial number was 83% less, respiration down 30%, but development similar to normal amelanotic cells.

A little known, avian anatomical conundrum may help resolve melanin paradoxes. One of many unique adaptations to flight, the pecten, strange intra-ocular organ with unresolved function(s), is much enlarged and heavily melanized in birds fighting gravity, hypoxia, thirst and hunger during long-distance, frequently sub-zero, non-stop migration. The pecten may help cope with energy and nutrient needs under extreme conditions, by a marginal but critical, melanin-initiated conversion of light to metabolic energy, coupled to local metabolite recycling.

Similarly in Central Africa, reduction in body hair and melanin increase may also have lead to ‘photomelanometabolism’ which, though small scale/ unit body area, in total may have enabled a sharply increased development of the energy-hungry cortex and enhanced human survival generally. Animal inability to utilize light energy directly has been traditionally assumed. Melanin and the pecten may have unexpected lessons also for human physiology and medicine.

Article Sources

  • [ii] Association Between Visceral Obesity and Sarcopenia and Vitamin D Deficiency in Older Koreans: The Ansan Geriatric Study. J Am Geriatr Soc. 2012 Feb 8. Epub 2012 Feb 8. PMID: 22316299
  • [iii] Association of plasma vitamin D levels with adiposity in Hispanic and African Americans. Anticancer Res. 2005 Mar-Apr;25(2A):971-9. PMID: 19549738
  • [iv] Walter E Lowell, George E Davis. The effect of solar cycles on human lifespan in the 50 United states: variation in light affects the human genome. Med Hypotheses. 2010 Jul;75(1):17-25. Epub 2010 May 7. PMID: 20452128
  • [v] Mirjam Münch, Friedrich Linhart, Apiparn Borisuit, Susanne M Jaeggi, Jean-Louis Scartezzini. Effects of prior light exposure on early evening performance, subjective sleepiness, and hormonal secretion. Behav Neurosci. 2012 Feb ;126(1):196-203. Epub 2011 Dec 26. PMID: 22201280
  • [vi] Geoffrey Goodman, Dani Bercovich. Melanin directly converts light for vertebrate metabolic use: heuristic thoughts on birds, Icarus and dark human skin. J Altern Complement Med. 2008 Jan-Feb;14(1):17-25. PMID: 18479839

Quantum computers to crack the world

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Quantum computing core

The modern world is a house of cards built upon encryption.

Make a mobile phone call and encryption is there to stop eavesdroppers listening in.

Spend money online and encryption ensures your card number and identity cannot be scooped up and used elsewhere.

And the money that keeps global banking systems lubricated only does so thanks to cryptographic software that turns a stream of data into unintelligible nonsense.

Remove all that encryption and the whole lot comes tumbling down.

If that happens we might return to an era when commerce was mostly done face-to-face and based around who you know.

Scrambled

Yet quantum computers – another modern marvel – are threatening to make this doomsday scenario a reality.

Why?

“Because of the possibilities for massive parallelism,” says Prof Mark Manulis, a cryptographic expert from the University of Surrey’s department of computing.

In other words, because of a quantum computer’s potential ability to do trillions of calculations a second.

When a message is scrambled with a modern encryption system, the keys used to lock it are typically very large numbers – tens, if not hundreds, of digits long.

Finding that key means using a computer to carry out lots of sums and then trying each answer to see if it unlocks a message an attacker is interested in.

1960s newsagent
If encryption fails then we might return to a very different type of commerce

The sheer number of possible answers lends protection because it would take centuries, or longer, to find the right key.

Unless large-scale quantum computers are commonplace, says Prof Manulis.

“Start Quote

Currently we can give you a tank with concrete enforcement – it’s secure but big”

Dr Tanja LangeTechnical University of Eindhoven

Quantum computers can crank through those sums so fast because their basic building blocks, known as qubits, can be used to represent both a zero and a one at the same time.

By contrast the computational elements, bits, of the classical computers under our desks and on our laps represent either a zero or a one. Not both.

The curious properties of the quantum realm mean that when those qubits work together you get a vast rise in computational power – hence the potential they have to speed things up, find keys and crack codes.

Number crunching

Most significantly affected by the arrival of quantum computers are the public key infrastructure (PKI) systems we use to establish secure channels of communication online.

Typically, when you turn up at a website it is PKI that sets up the initial connection. With that secure channel created, different encryption systems that are much less susceptible to attack by quantum computers are used to protect data shuttling back and forth.

“Public key cryptography is based on problems from number theory, integer factorisation and discrete logarithms, that will be broken once we have powerful quantum computers,” said Prof Manulis.

D-Wave quantum processor
Canadian firm D-Wave sells a working quantum computer

The key word here is “once”.

But that once might be a long time coming, believes Dr Stephan Ritter, who studies quantum computers at the Max Planck Institute for Quantum Optics in Garching, Germany.

“Quantum computers are not very powerful at the moment but they have this potential, and that’s what this is about,” he told the BBC.

“Experimentally I would say that we are at the stage where it’s not even clear which physical elements they will be made of.”

Researchers have yet to agree on the best way to build these qubits and how to link them together. So far, Dr Ritter says, only quantum computers with a small handful of qubits have been made – a long way from the hundreds and thousands needed to make it able to do useful work and do it quickly.

“There are proofs of concept of these building blocks but they all have advantages or disadvantages, so it’s unclear which will be the best as we go forward,” he says.

Controversial

Despite what Dr Ritter sees as a lack of progress, Canadian firm D-Wave will sell you a working quantum computer if you have $15m (£8.9m) to spare.

The way it operates is controversial and its price suggests it will not be the widely available device that can crack all our codes.

Even when they are available, says Dr Ritter, we should not think of them as wonder machines that speed up any and every batch processing job or database search.

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“They are good for very specific tasks,” he says, “but not everything is faster with a quantum computer and there will be many tasks you will not use one for at all.”

As a result we should have a few years yet to update and improve our encryption systems as research and development work on quantum computers continues.

‘Badly broken’

That’s just as well, says Dr Tanja Lange, a coding theory and cryptology expert from the Technical University of Eindhoven, as it can take a long time for older encryption systems to be swapped out in favour of more secure alternatives.

For instance, she says, it took five to six years to swap out the widely used MD5 data scrambling system once its weakness was demonstrated through a viable attack. Timescales can stretch for systems already used widely in the field, such as those found in cash machines, smart cards and mobile phones.

“However, if a system is absolutely badly broken, roll-out can be faster,” she says. “RSA sent new tokens promptly after they had a break-in and credit card companies are used to replacing cards if there is a risk that they were compromised.”

Woman on phone
Encryption ensures that no-one can listen in to you while you walk and talk

What will be harder, she says, is migrating everyone to the software systems that can resist attack by quantum computer. At the very least such systems require much bigger encryption keys and that means they are much less efficient – for which read, slower.

“We hope that with another three to five years of research we can design systems that are smaller, but we’re not there yet,” she says.

“Currently we can give you a tank with concrete enforcement – it’s secure but big.

“We hope to find a way to give you a secure sports car with airbags, ABS and all that neatly hidden away in a sleek design.”