From the desk of Zedie.
Plastic is perhaps one of the hugest environmental problems facing Humankind and virtually all animal species around the globe. Being well known for it’s low weight, every year over 300 million tons of plastic are produced in the planet. Estimations report more plastic produced in the first decade of the 21st century, than the entire amount produced in the last century.
|Primary fruiting structures of Pestalotiopsis microspora and Pestalosphaeria hansenii: (a) an acervulus of Pestalotiopsis microspora; (b) appendage-bearing conidiospores of Pestalotiopsis microspora; (c) a perithicium of Pestalosphaeria hansenii with an agglutinated mass of ascospores; (d) the asci of Pestalosphaeria hansenii located within a perithecium.|
The number of people who donated their organs after death in Scotland has almost doubled over a six-year period, according to government figures.
A total of 106 people donated organs in hospitals across Scotland last year compared with 54 in 2007.
The statistics showed a 62% increase in organ transplants from deceased donors, with 341 operations carried out.
However, about 600 people remain on the transplant waiting list.
Some 2,110,881 people living in Scotland have now joined the UK Organ Donor Register.
The figure means 40% of the Scottish population has registered, compared to 32% across the UK as a whole.
Public Health Minister Michael Matheson said: “First and foremost I want to offer my thanks to every donor and every donor’s family in Scotland who have demonstrated such kindness and benevolence in the face of tragic and difficult circumstances.
“It is our responsibility to ensure that people’s organ donation wishes are respected and to ensure that we make every donation count.”
Mr Matheson added: “It’s important to remember, however, that around 600 people in Scotland are still waiting for an organ and we must be doing all we can to give them hope.”
Peter McGeehan, 64, from Dunfermline, suffered serious heart failure and was listed for a transplant in 2004. In the ten years since a heart transplant, the father-of-two said he has thought about his donor every day.
He said: “People take living for granted, but as I approach the ten-year anniversary I can honestly say there’s never a day where I’ve woken up and haven’t thought about my unnamed donor.”
The competition to build Europe’s next generation of polar-orbiting weather satellites has been won by Airbus.
The big aerospace concern was declared the winner at the latest meeting of the European Space Agency’s (Esa) Industrial Policy Committee (IPC).
A contract valued in the hundreds of millions of euros will be signed by Esa and Airbus in due course.
The existing Metop series, as it is known, has a profound impact on the quality of weather forecasting.
The satellites’ sensors gather profiles of atmospheric conditions, layer by layer.
Studies comparing all the different types of meteorological observations (including surface weather stations, balloons and aeroplanes, etc) have found Metop data to have the biggest single contribution to the accuracy of the 24-hour look ahead, at around 25%.
The improved forecasts of storms and other extreme events are estimated to be worth billions of euros annually in terms of lives saved and property damage avoided.
Thursday’s IPC decision is therefore a critically important one for the continent, by ensuring there is continuity of data when the existing series of Metop satellites is retired.
“Metop first generation has established itself as an essential series of satellites for weather forecasting. It gives the most detailed measurements from space for such purposes,” explained Esa programme manager Graeme Mason.
“The first objective of the second generation (SG) is simply to continue the observations without a gap because we cannot do without them. But we want also to improve the measurements – to improve the resolution, to see finer details in the atmosphere.
“And the third objective is to make additional measurements, and we’ll be flying a couple of new instruments,” he told BBC News.
Metop-SG will carry 11 instruments spread across two platforms. This is a major difference from the first generation series which packs all the sensors on to a single satellite. Two of these spacecraft have so far been launched; a third will go up at the end of the decade.
Another major difference between the two series will be the approach to end-of-life decommissioning.
The first series will be de-orbited by nudging them down from their roughly 800km-high operational altitude until they are caught by the atmosphere, and pulled in to burn to destruction. This should take no more than 25 years, to comply with international space-debris guidelines.
The disposal of the second generation, however, will be faster and more controlled.
The satellites will fly with bigger fuel tanks and more powerful thrusters, enabling them to target their destructive dive on to an uninhibited region of the South Pacific.
The whole procedure should take just a month.
Esa says the accumulation of old hardware in orbit is becoming a significant issue and the plans for Metop-SG demonstrate the seriousness with which it is tackling the problem.
The competitors for the SG contract were given an additional two months to work out how best to carry out the de-orbiting. It will mean two thirds of the fuel on each spacecraft being reserved just for the end-of-life manoeuvres.
The first pair of Metop-SG satellites should launch in 2021/22. The third and final pair will likely go up in the 2030s, ensuring continuity of data deep into the 2040s.
Airbus will use its facilities in Germany, France and the UK for most of the work on Metop-SG.
Lithium, a key ingredient in lightweight batteries, is already powering the modern world, and could be key to getting the world to reduce its reliance on fossil fuels.
Look at a satellite image of South America. Halfway down on the left-hand-side is a distinctive white splodge.
Close up, that splodge turns out to be one of the most extraordinary and unspoilt places on earth, the world’s biggest salt flat.
It is a crisp, perfectly flat white plain, like freshly fallen snow, 100km (60 miles) across and 3,600m (12,000ft) up in the remote Bolivian Andes.
This is the Salar de Uyuni and this hauntingly beautiful place could be part of the key to tackling climate change, helping to wean the world away from fossil fuels.
Which is why, pristine as it may be, the chances are that 50 years from now it will all be gone – dredged, crystallised and then carted away.
That’s because under its thick salt crust, the Salar de Uyuni is also the world’s biggest single deposit of lithium, accounting for perhaps a third of the world’s resources of this alkaline metal.
Go back to the 1980s, and lithium was one of the more obscure members of the periodic table, much as its next-door neighbour beryllium remains today.
That all began to change in 1991, when Sony launched the first ever portable gadget powered by a lithium-ion battery.
Today, of course, the words “lithium” and “battery” are almost synonymous – this soft metal is in all our smartphones, tablets and laptops.
The secret of lithium’s success is that it is the third element of the periodic table, after the gases hydrogen and helium.
Its tiny atoms, containing just three protons each, make lithium the lightest of all metals.
In its pure form, lithium will actually float on the oil it is normally stored in by chemists.
And it is stored in oil, under the inert gas argon, for a reason.
For lithium is also the first of the alkali metals – like its near kin sodium and potassium, it will react spontaneously to water, though not quite as violently as those other two.
All of which makes lithium an ideal material for light-weight batteries.
“We think of batteries as producing an electrical current, sending electrons around a circuit,” explains chemistry professor Andrea Sella of University College London.
“But of course, as a chemist, I am interested in what goes on inside the battery. And for every electron, a lithium ion also has to move inside the battery.”
Being so small, the atoms slip easily between the layered materials that make up the battery.
And being so light, lithium is the most energy dense of battery materials – meaning it stores the most energy for a given weight.
This is why lithium is so important for the battle against climate change. It is the optimum battery material if you need to carry your energy store with you – in a gadget, or in a car.
Batteries are not the only things that take advantage of lithium’s unique electrochemical properties.
The human body does as well.
“Lithium saved my life. I would be dead or in the back wards without it,” says Kay Redfield Jamison, professor of psychiatry at Johns Hopkins School of Medicine.
Professor Jamison is an expert on bipolar disorder – also known as manic depression – who herself suffers from the condition.
Like many sufferers of bipolar illness she says pills made of purified lithium carbonate, the same naturally-occurring substance that is mined in many salt lakes today, has helped smooth out the frenetic highs and suicidal lows of this disease.
“When against medical advice I haven’t been on it, I almost immediately started getting manic and then suicidally depressed,” she says.
And while those on lithium do not exactly have a normal life – the pills can cause nausea and leave them feeling emotionally inhibited – it has prevented many from taking their own lives.
How this happens remains something of a mystery.
However, it probably has something to do with the fact that our nerves and brains don’t operate using flows of electrons, as you may imagine.
Instead, they rely on flows of ions – positively charged particles of sodium and potassium.
It may be that lithium ions soften the swings between overactive and underactive flows of these ions that researchers theorise are behind bipolar disorder.
Medicine is likely to continue to use a steady supply of lithium, but according to the Argentine mining company SQM, the reason demand for the metal has been growing at 20% a year is increased demand for lithium batteries.
And the biggest driver of demand is not for gadgets, but for cars.
Fuel-efficient hybrid cars, which use electric motors powered by lithium batteries alongside conventional gasoline or diesel engines, are proving very popular.
The market for pure electric vehicles has been slower to develop, thanks in large part to the limitations of lithium batteries.
“In its pure form, lithium actually has the same energy density as gasoline,” explains Prof Nigel Brandon of Imperial College in London, one of thousands of researchers engaged in a huge worldwide effort to eke out ever better performance from our batteries.
“But we cannot use lithium in its pure form. We have to store it in other materials, and that dilutes the energy density of batteries in practice.”
Throw in the weight of the two electrodes, the casing, the electrolyte fluid and so on, and the energy-storing performance of your average electric car battery turns out to be only one 50th as good as a tank of petrol.
How a lithium-ion battery works
- It is conventional with lithium batteries to refer to the negative electrode as the anode, and the positive electrode as the cathode. The two electrodes, with an electrically insulating separator between them, are often rolled up like a Swiss roll.
- During discharge, electrical current flows from the anode to the cathode through the device the battery is powering (symbolised here by a light bulb). Simultaneously, positively charged lithium ions travel from the anode to the cathode through the separator.
- On reaching the cathode, the lithium ions embed themselves in its metal oxide structure, which simultaneously accepts electrons from the external circuit.
- The anode is typically made of carbon, the cathode is typically made of a cobalt or manganese oxide. The electrolyte (the liquid surrounding the electrodes) is usually composed of lithium salts in an organic solvent, such as ether.
- During charging the process occurs in reverse.
That matters, because the less energy the battery can store, the more limited the car’s range.
The limited range of electric cars is one of the main reasons people are unwilling to switch to them.
But the good news is there is scope for improvement.
Professor Brandon reckons we could see a five-fold increase in energy density over the next two decades, perhaps even 10-fold or more, if new technologies prove successful.
A lot of current research is focused on “lithium-air” batteries, where much of the battery would be replaced with oxygen drawn from the atmosphere.
Even so, says Professor Brandon, the limits of lithium battery chemistry mean they will never come near gasoline in terms of energy density.
Indeed, in most handheld gadgets improvements in running time have had less to do the performance of batteries than with the great steps that have been made reducing power consumption.
The same is likely to be true for electric vehicles for the foreseeable future – engineers will have to design them around the limitations of batteries.
Limits on energy density are not the only problem, because it is not the only thing you care about in a battery.
Otherwise, why have lead-acid batteries in traditional petrol-driven cars, given that lead is the heaviest stable element in the periodic table?
The reason is that lead provides two things that lithium currently cannot – the surge of power needed to fire up your engine, and incredible durability over thousands of cycles of the battery, no matter how hot or cold the weather.
As an alkali metal, lithium’s high reactivity turns out to be a bit of an Achilles’ heel, because unwanted chemical reactions inside the battery cause it to degrade over time.
And while that may be fine in a phone, that has a typical working life of two-to-three years, it is much more of a headache if you want your car battery to last closer to a decade.
Durability is not the only trade-off that researchers like Prof Brandon have to grapple with.
The battery also has to be safe, and cheap.
And, as certain plane and car manufacturers have discovered, lithium batteries do occasionally overheat and catch fire.
Nonetheless, we prize the freedoms batteries give us and the electro-chemical properties of lithium mean it will remain central to their future.
All of which brings us back to South America.
Bolivia’s Salar de Uyuni is one corner of a “Lithium Triangle” that also takes in the northern ends of Chile and Argentina.
These three countries dominate world lithium supplies thanks to the incredible geological forces shaped the South American continent.
The subduction of the Pacific plate under Chile’s coast, and the resulting tectonic uplift of South America, created large localised depressions which cause water to flow into lakes instead of escaping into the sea.
The lithium salts that dissolve out of the surrounding rocks collect in these great lakes.
And the Andes themselves play a key role.
They squeeze almost every drop of water out of the prevailing winds off the Atlantic, making the western slopes some of the direst places on earth.
This dry climate causes these lakes to evaporate, leaving behind the crystallised salts you see at the salt flats of the Salar de Uyuni and at the Salar de Atacama, in the middle of the Atacama desert – the driest place on earth.
The Salar de Atacama is not as picturesque as the Salar de Uyuni because of the dust that blows in from the surrounding desert, but it is the biggest single source of lithium currently being mined.
So why is the Salar de Uyuni virtually untouched while this place is so busy?
Geography is part of the reason.
The Atacama deposit is richer in lithium than Uyuni and is easier to exploit because it is nearer the sea and, instead of stuck at the top of a mountain range, it is on a flat plain.
That makes the roads and infrastructure needed for export much cheaper.
But politics is also a key factor.
The Salar de Atacama is controlled by a government in Santiago that has a long and happy working relationship with the foreign mining companies who have exploited Chile’s largest mineral resource, copper.
Contrast that with the radical-left Bolivian government which has vowed not to sell out to Western companies – assuming those Western companies would trust the government not to expropriate them.
But, if the world is to meet the future demand, other deposits will need to be opened up.
Most are in problematic locations – Tibet, Afghanistan, and of course Bolivia.
If the Bolivian government can learn to work with foreigners who have the necessary expertise and deep pockets to bring the stuff to market, then the Salar de Uyuni could prove a bonanza for one of the poorest countries in South America.
And the Bolivians have just begun a pilot mining project.
So visit this incredible location now, if you can, because there may not be much left of it once the lithium miners have finished their work.
Electronic cigarettes didn’t help smokers quit or even smoke less, according to a longitudinal study that may quash some public health hopes for the nicotine-delivery devices.
Smokers who also reported any e-cigarette use at baseline in the web-based study weren’t significantly more likely to have quit tobacco 1 year later (odds ratio 0.71, P=0.35), said Pamela Ling, MD, MPH, of the University of California San Francisco.
The same was true for prior 30-day e-cigarette use after accounting for baseline intent to quit, cigarette consumption, and dependence (OR 0.76, P=0.46), the group reported in a research letter online in JAMA Internal Medicine.
Among people who didn’t quit, “vaping” wasn’t associated with smoking fewer cigarettes over time either (P=0.25).
These findings from analysis of 949 smokers in a nationally representative panel followed from 2011 through 2012 by web-based market research firm Knowledge Networks (now GfK) add to similar findings from population-based and Quitline studies.
“Although electronic cigarettes are aggressively promoted as smoking cessation aids, studies of their effectiveness for cessation have been unconvincing,” Ling’s group wrote.
For example, one placebo-controlled but underpowered trial suggested e-cigarettes were at least as good as nicotine patches in helping smokers quit, but quit rates were dismal either way at 6% to 7%.
“Regulations should prohibit advertising claiming or suggesting that e-cigarettes are effective smoking cessation devices until claims are supported by scientific evidence,” Ling’s group argued.
The top reason for regular e-cigarette use cited in surveys has been kicking the tobacco habit, and some public health experts have been cautiously supporting that harm-reduction strategy.
“As a harm reduction proponent, I would be willing to put aside the fact that any product with the name ‘cigarette’ (e- or otherwise) causes me reflex tachycardia and support electronic cigarettes … if there were good data indicating that they helped smokers to stop,” JAMA Internal Medicine editor Mitchell Katz, MD, wrote in a note accompanying Ling’s letter.
However, he agreed with their conclusion and further advocated FDA regulation as drug-delivery devices.
While the U.S. Supreme court struck down FDA attempts to regulate e-cigarettes as drugs or devices in 2010, the agency has regulations in the works that are expected to generally bring the same kind of restrictions to e-cigarettes as to other tobacco products.
“The bottom line is e-cigarettes are not a good way to quit,” commented Brian Tiep, MD, director of smoking cessation at City of Hope in Duarte, Calif.
The devices may not have all the carcinogenic compounds found in burning tobacco, but that doesn’t mean they’re entirely safe, he told MedPage Today, pointing to FDA analyses finding carcinogenic nitrosamines and the antifreeze component diethylene glycol in e-cigarette nicotine solutions.
However, he noted that Ling’s study population wasn’t actively trying to quit and that an adequately-powered study is still needed to assess e-cigarettes’ performance in a smoking cessation program.
Ling’s group also cautioned about limited statistical power, as smoking cessation was self-reported and included only nine of the 88 e-cigarette users.
Their study lacked data on how frequently the population used e-cigarettes and motivation for use as well.
The data came from a study funded by the National Cancer Institute.
An elderly organ in a living animal has been regenerated into a youthful state for the first time, UK researchers say.
The thymus, which is critical for immune function, becomes smaller and less effective with age, making people more susceptible to infection.
A team at the University of Edinburgh managed to rejuvenate the organ in mice by manipulating DNA.
Experts said the study was likely to have “broad implications” for regenerative medicine.
The thymus, which sits near the heart, produces T-cells to fight off infection.
However, by the age of 70 the thymus is just a tenth of the size in adolescents.
“This has a lot of impacts later in life, when the functionality of the immune system decreases with age and you become more vulnerable to infection and less responsive to vaccines,” one of the researchers, Dr Nick Bredenkamp, told the BBC.
The team at the MRC Centre for Regenerative Medicine at the University of Edinburgh tried to regenerate the thymus of old mice.
A gene, called Foxn1, naturally gets shut down as the thymus ages. So they tried to boost it back to youthful levels.
A drug was used to increase the activity of the gene in elderly mice.
The results, published in the journal Development, showed that boosting Foxn1 activity in elderly mice could give them the thymus of a much younger animal.
Dr Bredenkamp said: “We could regenerate the thymus using this method. It increases in size and makes more T-cells. It is almost completely regenerated.
“The exciting thing really is the manner in which it is done. We’ve targeted a single gene and we’ve been able to regenerate an entire organ.”
It is not certain why the thymus shrinks with age. One theory is that it needs a lot of energy to run, which the body starts to divert towards reproduction during adolescence.
Dr Bredenkamp argued that the technique could eventually be adapted to work in people, but it would need to be “very tightly controlled” to ensure the immune system did not then go into overdrive and attack the body.
It also raises the prospect that other organs in the body, such as the brain or heart, could be made more youthful by targeting a single gene.
Dr Rob Buckle, the head of regenerative medicine at the Medical Research Council, said: “One of the key goals in regenerative medicine is harnessing the body’s own repair mechanisms and manipulating these in a controlled way to treat disease.
“This interesting study suggests that organ regeneration in a mammal can be directed by manipulation of a single protein, which is likely to have broad implications for other areas of regenerative biology.”
They set out to design a new low-power, light-weight anchor forautonomous underwater vehicles.
“Luckily, nature had already done the work for us,” said Dr Kerstin Nordstrom, of the University of Maryland, who collaborated on the research.
The answer was poking out of mudflats off the coast at nearby Gloucester, MA.
The Atlantic razor clam, Ensis directus, has been dubbed “the Ferrari of underwater diggers”.
An animal of its modest frame (10-20cm) should only be strong enough to penetrate 2cm into packed sand. But it can burrow up to 70cm in just over a minute.
Compared to existing anchor technology “the razor clam is about 10 times more efficient,” Dr Nordstrom told the BBC’s Science in Action.
To dig for half a kilometre, it would only use the energy in an AA battery.
“But when you try plunging the shell into the sand, it doesn’t actually penetrate very far,” said Dr Nordstrom.
“What this shows is the clam must be actively doing something to the ground when it digs.”
To find out the razor clam’s secret, they studied its digging action and modelled it mechanically.
The repeated open-shut of the clam’s valves turned the hard-packed soil around it into quicksand.
“The clam’s trick is to move its shells in such a way as to liquefy the soil around its body, reducing the drag acting upon it,” said Amos Winter, of MIT’s Department of Mechanical Engineering.
“Pushing through sand costs a lot of energy. But if the sand is excited, it’s actually very easy. That’s the trick,” added Dr Nordstrom.
By mimicking the action of the razor clam, they built their own robotic prototype – which has achieved the same digging speed – about 1cm per second.
The first “RoboClam” can only reach 20cm, and requires a significant rig of machinery to propel it.
But having demonstrated the principle, the team now aims to develop a larger, self-contained unit, that can burrow more than 10 metres.
This could be used to anchor larger vessels, and may have military applications – such as detonating mines, the researchers suggest.
“The cool thing is this technology is already 10 times more efficient than any anchor. If we can keep scaling things up, some day it will affect big boats,” said Dr Nordstrom.
“Also – undersea cable installation is happening more and more frequently. If we can do it more efficiently we can save costs and cause less disturbance to the environment,” she said.
Amos Winter agrees: “Having a system that could just latch onto the cable, work its way along, and automatically dig it into the soil would be great,” he said.