Friday, 21 December 2018
The Twelve (Scientific) Days Of Christmas
As Christmas approaches and we get over-saturated in seasonal pop songs and the occasional carol, I thought it would be appropriate to look at a science-themed variation to this venerable lyric. So without further ado, here are the twelve days of Christmas, STEM-style.
Wednesday, 12 December 2018
New neurons: astrocytes, gene therapy and the public fear of brain modification
Ever since the first cyberpunk novels of the early 1980s - and the massive increase of public awareness in the genre thanks to Hollywood - the idea of artificially-enhanced humans has been a topic of intense discussion. Either via direct augmentation of the brain or the development of a brain-computer interface (BCI), the notion of Homo superior has been associated with a dystopian near-future that owes much to Aldous Huxley's Brave New World. After reading about current research into repairing damaged areas of the brain and spinal cord, I thought it would be good to examine this darkly-tinged area.
Back in 2009 I posted about how science fiction has to some extent been confused with science fact, which coupled with the fairly appalling quality of much mainstream media coverage of science stories, has led to public fear where none is necessary and a lack of concern where there should be heaps. When it comes to anything suggestive of enhancing the mind, many people immediately fall back on pessimistic fictional examples, from Frankenstein to Star Trek's the Borg. This use of anti-scientific material in the consideration of real-world STEM is not an optimal response, to say the least.
Rather than working to augment normal humans, real research projects on the brain are usually funded on the basis that they will generate improved medical techniques for individuals with brain or spinal cord injuries. However, a combination of the fictional tropes mentioned above and the plethora of internet-disseminated conspiracy theories, usually concerning alleged secret military projects, have caused the public to concentrate on entirely the wrong aspects.
The most recent material I have read concerning cutting-edge work on the brain covers three teams' use of astrocytes to repair damaged areas. This is an alternative to converting induced pluripotent stem cells (iPSCs) to nerve cells, which has shown promise for many other types of cell. Astrocytes are amazing things, able to connect with several million synapses. Apparently Einstein's brain had far more of them than usual in the region connected with mathematical thinking. The big question would be whether this accumulation was due to nature or nurture, the latter being the high level of exercise Einstein demanded of this region of his brain.
Astrocyte research for brain and spinal cord repair has been ongoing since the 1990s, in order to discover if they can be reprogrammed as functional replacements for lost neurons without any side effects. To this end, mice have been deliberately brain-damaged and then attempts made to repair that damage via converted astrocytes. The intention is to study if stroke victims could be cured via this method, although there are hopes that eventually it may also be a solution for Parkinson's disease, Alzheimer's and even ALS (motor neurone disease). The conversion from astrocyte to neuron is courtesy of a virus that introduces the relevant DNA, although none of the research has as yet proven that the converted cells are fully functional neurons.
Therefore, it would seem we are some decades away from claiming that genetic manipulation can cure brain-impairing diseases. But geneticists must share some of the blame for giving the public the wrong impression. The hyperbole surrounding the Human Genome Project gave both public and medical workers a false sense of optimism regarding the outcome of the genome mapping. In the late 1990s, a pioneer gene therapist predicted that by 2020 virtually every disease would include gene therapy as part of the treatment. We are only just over a year short of this date, but most research is still in first phase trial - and only concern diseases that don't have a conventional cure. It turned out that the mapping was just the simplest stage of a multi-part programme to understand the complexities of which genes code for which disorders.
Meanwhile, gene expression in the form of epigenetics has inspired a large and extremely lucrative wave of pseudo-scientific quackery that belongs in the same genre as homeopathy, crystal healing and all the other New Age flim-flam that uses real scientific terminology to part the gullible from their cash. The poor standard of science education outside of schools (and in many regions, probably within them too) has led to the belief that changing your lifestyle can fix genetic defects or affect cures of serious brain-based illnesses.
Alas, although gene expression can be affected by environmental influences, we are ultimately at the mercy of what we inherited from our parents. Until the astrocyte research has been verified, or a stem cell solution found, the terrible truth is that the victims of strokes and other brain-based maladies must rely upon established medical treatments.
This isn't to say that we may in some cases be able to reduce or postpone the risk with a better lifestyle; diet and exercise (of both the body and brain) are clearly important, but they won't work miracles. We need to wait for the outcome of the current research into astrocytes and iPSCs to find out if the human brain can be repaired after devastating attacks from within or without. Somehow I doubt that Homo superior is waiting round the corner, ready to take over the world from us unenhanced humans…
Back in 2009 I posted about how science fiction has to some extent been confused with science fact, which coupled with the fairly appalling quality of much mainstream media coverage of science stories, has led to public fear where none is necessary and a lack of concern where there should be heaps. When it comes to anything suggestive of enhancing the mind, many people immediately fall back on pessimistic fictional examples, from Frankenstein to Star Trek's the Borg. This use of anti-scientific material in the consideration of real-world STEM is not an optimal response, to say the least.
Rather than working to augment normal humans, real research projects on the brain are usually funded on the basis that they will generate improved medical techniques for individuals with brain or spinal cord injuries. However, a combination of the fictional tropes mentioned above and the plethora of internet-disseminated conspiracy theories, usually concerning alleged secret military projects, have caused the public to concentrate on entirely the wrong aspects.
The most recent material I have read concerning cutting-edge work on the brain covers three teams' use of astrocytes to repair damaged areas. This is an alternative to converting induced pluripotent stem cells (iPSCs) to nerve cells, which has shown promise for many other types of cell. Astrocytes are amazing things, able to connect with several million synapses. Apparently Einstein's brain had far more of them than usual in the region connected with mathematical thinking. The big question would be whether this accumulation was due to nature or nurture, the latter being the high level of exercise Einstein demanded of this region of his brain.
Astrocyte research for brain and spinal cord repair has been ongoing since the 1990s, in order to discover if they can be reprogrammed as functional replacements for lost neurons without any side effects. To this end, mice have been deliberately brain-damaged and then attempts made to repair that damage via converted astrocytes. The intention is to study if stroke victims could be cured via this method, although there are hopes that eventually it may also be a solution for Parkinson's disease, Alzheimer's and even ALS (motor neurone disease). The conversion from astrocyte to neuron is courtesy of a virus that introduces the relevant DNA, although none of the research has as yet proven that the converted cells are fully functional neurons.
Therefore, it would seem we are some decades away from claiming that genetic manipulation can cure brain-impairing diseases. But geneticists must share some of the blame for giving the public the wrong impression. The hyperbole surrounding the Human Genome Project gave both public and medical workers a false sense of optimism regarding the outcome of the genome mapping. In the late 1990s, a pioneer gene therapist predicted that by 2020 virtually every disease would include gene therapy as part of the treatment. We are only just over a year short of this date, but most research is still in first phase trial - and only concern diseases that don't have a conventional cure. It turned out that the mapping was just the simplest stage of a multi-part programme to understand the complexities of which genes code for which disorders.
Meanwhile, gene expression in the form of epigenetics has inspired a large and extremely lucrative wave of pseudo-scientific quackery that belongs in the same genre as homeopathy, crystal healing and all the other New Age flim-flam that uses real scientific terminology to part the gullible from their cash. The poor standard of science education outside of schools (and in many regions, probably within them too) has led to the belief that changing your lifestyle can fix genetic defects or affect cures of serious brain-based illnesses.
Alas, although gene expression can be affected by environmental influences, we are ultimately at the mercy of what we inherited from our parents. Until the astrocyte research has been verified, or a stem cell solution found, the terrible truth is that the victims of strokes and other brain-based maladies must rely upon established medical treatments.
This isn't to say that we may in some cases be able to reduce or postpone the risk with a better lifestyle; diet and exercise (of both the body and brain) are clearly important, but they won't work miracles. We need to wait for the outcome of the current research into astrocytes and iPSCs to find out if the human brain can be repaired after devastating attacks from within or without. Somehow I doubt that Homo superior is waiting round the corner, ready to take over the world from us unenhanced humans…
Thursday, 29 November 2018
Setting low standards: bovine TB, badger culls and political pressure on science
If there's a single type of news story that's almost guaranteed to generate widespread sympathy across the British Isles it is one concerning the mistreatment of animals. Over the past five years, badger culls aimed at preventing the spread of bovine tuberculosis have generated much public debate, with opinions varying from those who think badgers are completely innocent victims to some who want to see the species eradicated anywhere domestic cattle are kept. Since the number of farmed cattle in the British Isles is close to ten million, this presumably means the no-badger zone is rather on the large size!
When debates concerning agriculture start to get overheated it usually reduces to a battleground between farmers and so-called townies, with mudslinging and emotive slogans taking precedence over the facts. In this particular case the badgers have an unusual ally in the form of rock musician and amateur astronomer Brian May, who has received much of the criticism usually reserved for tree huggers, animal rights' campaigners and environmentalist types in general.
As I've mentioned before, a species often receives support based more on its cuteness factor than anything else (I consider the irascible and curmudgeonly Mr Badger in Wind in the Willows as a fairly accurate representation of the true critter) so the farming community has seen fit to complain that ignorant, urban-based activists are unaware of the challenges Mother Nature throws at the agricultural sector.
Such stereotyping and reductionism does nothing to alleviate the issue, which other nations face in similar circumstances. New Zealand, for example, has a rapidly escalating battle over the use of 1080 to poison introduced predators. Even though many environmental organisations such as Forest and Bird proclaim it the most effective method the debate is far from settled, with the anti-1080 movement using emotive pleas in their campaign that at times combines hysteria and aggression in equal measure.
The UK's Department for Environment, Food and Rural Affairs (Defra) has funded an independent scientific review from Oxford University as to the efficacy of the cull, resulting in popular press reports that the evidence does not support it. Indeed, the high ratio of dead badgers in return for a 'modest' reduction in the disease has been given as a key reason to stop the culls. This might appear to be a nod towards animal welfare, until you read that other issues include their cost and complexity and a desire for the Government to gain in the opinion polls. A key scientific argument against the effectiveness of the culls come from rural vets, who support data suggesting even at maximum success, the reduction in new cases of cattle TB would only be 12-16% - in exchange for a culling of over 70% of local badger populations.
So what does this example say about humanity's attitude towards the environment and the use of science to reinforce that attitude? In terms of numbers of individuals, humans and our domesticated species (both livestock and household pets) vastly outnumber the inhabitants of the wilderness. The once diverse ecosystem has been vastly reduced, predominantly in the temperate regions suitable for intensive farming. But in return for this largely irreversible loss we have gained all-year round access to an incredible variety of inexpensive foodstuffs; clearly, our gastronomic gains take precedence over the wider ecosystem.
In the case of wild badgers as disease vectors, it isn't just the livelihood of individual farmers that are at stake. The European Union's threat to impose trade sanctions on the UK, such as a ban on the export of live cattle, must be considered as a potential loss at the national level. Little wonder then that the British Government implemented the cull after what has been termed 'a randomised trial period' or more impressively, 'over fifteen years of intensive research.' Even so, was the result of all this enough to justify the finality of the chosen method - or was the scientific data manipulated in the name of political expediency?
One telling example of how the culling might have been ordered due to political pressure rather than any scientific smarts was the use of evidence from other nations that are successfully controlling bovine TB. Australia and New Zealand have been held up as examples of how control of the disease vectors can vastly reduce or indeed remove the problem altogether. Except of course that those two nations don't have any badgers; it is the possum, a semi-arboreal marsupial, that is responsible for the spread of tuberculosis there. It seems to me that two creatures from such vastly different lineages should never have been seen as workable comparisons; the natural world just doesn't fall into the neat categories we would like it to. As a matter of fact, the UK Government has partly blamed the lack of success on the badgers themselves for failing to follow predicted behaviour. In 2013 the then Environment Secretary Owen Paterson stated that the animals had cheated by 'moving the goal posts'!
The Oxford University research reports that far more cases of bovine TB result from transmission between cattle rather than directly from badgers, explaining that farmers are not following Defra guidelines to minimise the spread. Even Defra itself states that there has been not nearly enough implementation of badger-proof feed storage and fencing, while its chief scientific adviser, Ian Boyd, has been quoted as admitting that badgers may only be responsible for as little as 6% of bovine TB! This incidentally comes from the man who in 2013 wanted complete control over what scientific results were reported to Government ministers, presumably so as to maintain a clear-cut, pro-STEM political lobby. Hmm, methinks I smell something fishy...
What can we conclude from these shenanigans? If scientific research doesn't provide reliable support for a method, shouldn't the mistake be admitted and a new approach implemented? Science is the sole invention of humanity with built-in error correction but when it gets embroiled in politics, unabashed use of political tools such as spin can prove fatal. In this particular case, the fatalities in the short term were the badgers. In the long run, an unbalanced ecosystem would have resulted. And we all know which species likes to think of itself as the pinnacle of creation. There's enough denial of scientific results as it is, without distortion for the sake of political convenience. Let's hope Defra has the courage to own up and try other tactics against the wily badger.
When debates concerning agriculture start to get overheated it usually reduces to a battleground between farmers and so-called townies, with mudslinging and emotive slogans taking precedence over the facts. In this particular case the badgers have an unusual ally in the form of rock musician and amateur astronomer Brian May, who has received much of the criticism usually reserved for tree huggers, animal rights' campaigners and environmentalist types in general.
As I've mentioned before, a species often receives support based more on its cuteness factor than anything else (I consider the irascible and curmudgeonly Mr Badger in Wind in the Willows as a fairly accurate representation of the true critter) so the farming community has seen fit to complain that ignorant, urban-based activists are unaware of the challenges Mother Nature throws at the agricultural sector.
Such stereotyping and reductionism does nothing to alleviate the issue, which other nations face in similar circumstances. New Zealand, for example, has a rapidly escalating battle over the use of 1080 to poison introduced predators. Even though many environmental organisations such as Forest and Bird proclaim it the most effective method the debate is far from settled, with the anti-1080 movement using emotive pleas in their campaign that at times combines hysteria and aggression in equal measure.
The UK's Department for Environment, Food and Rural Affairs (Defra) has funded an independent scientific review from Oxford University as to the efficacy of the cull, resulting in popular press reports that the evidence does not support it. Indeed, the high ratio of dead badgers in return for a 'modest' reduction in the disease has been given as a key reason to stop the culls. This might appear to be a nod towards animal welfare, until you read that other issues include their cost and complexity and a desire for the Government to gain in the opinion polls. A key scientific argument against the effectiveness of the culls come from rural vets, who support data suggesting even at maximum success, the reduction in new cases of cattle TB would only be 12-16% - in exchange for a culling of over 70% of local badger populations.
So what does this example say about humanity's attitude towards the environment and the use of science to reinforce that attitude? In terms of numbers of individuals, humans and our domesticated species (both livestock and household pets) vastly outnumber the inhabitants of the wilderness. The once diverse ecosystem has been vastly reduced, predominantly in the temperate regions suitable for intensive farming. But in return for this largely irreversible loss we have gained all-year round access to an incredible variety of inexpensive foodstuffs; clearly, our gastronomic gains take precedence over the wider ecosystem.
In the case of wild badgers as disease vectors, it isn't just the livelihood of individual farmers that are at stake. The European Union's threat to impose trade sanctions on the UK, such as a ban on the export of live cattle, must be considered as a potential loss at the national level. Little wonder then that the British Government implemented the cull after what has been termed 'a randomised trial period' or more impressively, 'over fifteen years of intensive research.' Even so, was the result of all this enough to justify the finality of the chosen method - or was the scientific data manipulated in the name of political expediency?
One telling example of how the culling might have been ordered due to political pressure rather than any scientific smarts was the use of evidence from other nations that are successfully controlling bovine TB. Australia and New Zealand have been held up as examples of how control of the disease vectors can vastly reduce or indeed remove the problem altogether. Except of course that those two nations don't have any badgers; it is the possum, a semi-arboreal marsupial, that is responsible for the spread of tuberculosis there. It seems to me that two creatures from such vastly different lineages should never have been seen as workable comparisons; the natural world just doesn't fall into the neat categories we would like it to. As a matter of fact, the UK Government has partly blamed the lack of success on the badgers themselves for failing to follow predicted behaviour. In 2013 the then Environment Secretary Owen Paterson stated that the animals had cheated by 'moving the goal posts'!
The Oxford University research reports that far more cases of bovine TB result from transmission between cattle rather than directly from badgers, explaining that farmers are not following Defra guidelines to minimise the spread. Even Defra itself states that there has been not nearly enough implementation of badger-proof feed storage and fencing, while its chief scientific adviser, Ian Boyd, has been quoted as admitting that badgers may only be responsible for as little as 6% of bovine TB! This incidentally comes from the man who in 2013 wanted complete control over what scientific results were reported to Government ministers, presumably so as to maintain a clear-cut, pro-STEM political lobby. Hmm, methinks I smell something fishy...
What can we conclude from these shenanigans? If scientific research doesn't provide reliable support for a method, shouldn't the mistake be admitted and a new approach implemented? Science is the sole invention of humanity with built-in error correction but when it gets embroiled in politics, unabashed use of political tools such as spin can prove fatal. In this particular case, the fatalities in the short term were the badgers. In the long run, an unbalanced ecosystem would have resulted. And we all know which species likes to think of itself as the pinnacle of creation. There's enough denial of scientific results as it is, without distortion for the sake of political convenience. Let's hope Defra has the courage to own up and try other tactics against the wily badger.
Wednesday, 14 November 2018
Swapping gasoline with gas: are hydrogen fuel cells the future of land transport?
When I was a child, I recall being impressed by the sophistication of hydrogen fuel cells, a power source used in spacecraft that generated water as a by-product. What I didn't realise at the time was that the basis for fuel cell technology had been invented back in the 1830s. Now that automobile manufacturers are promoting fuel cell vehicles for consumers, is it time for the technology to expand from niche usage to mass market?
Road vehicles of all sorts have had more than their fair share of ups and downs, not least due to the conservatism of that unholy alliance between the internal combustion engine and fossil fuels sectors. Although there were hydrogen-powered test vehicles in 1970s, it wasn't until 1991 that the development phase was completed. There are currently three car manufacturers with fuel cell models intended for personal customers: the Honda Clarity, Hyundai Nexo and Toyota Mirai. The latter two are intended to enter to take off (not literally) across South Korea and Australia respectively over the new few years, apparently selling at a loss on the assumption of beating rivals Nissan and BMW into the market. Brand loyalty being what it is, and all.
So what do fuel cell vehicles have that makes them a credible alternative to gas guzzlers and electric cars? Their primary benefit in this time-poor age is that they take only minutes to refuel – and with a range considerably greater than that of electric vehicles. Even so, this is hardly likely to be a convincing argument for petrol heads.
To anyone with even a vague knowledge of interwar air travel, hydrogen brings to mind the Hindenburg and R101 disasters. The gas is far from safe in large quantities, hence the rapid end of airship development; even with helium as a substitute, today's airships are smaller, specialist vehicles, their lack of speed making them an unlikely substitute for passenger jets. Although fuel cells themselves provide a safe power source, large quantities of hydrogen needs to be transported to the refuelling stations. A neat solution is to transport it in the form of ammonia (admittedly hardly a pleasant substance itself) and then convert it to hydrogen at the point of use.
What is less easily resolved is the cost of manufacturing the gas and the resulting high price for the customer. Most of the world's hydrogen is produced from natural gas; it can be made from renewable sources, but only at much greater expense. Wind-to-hydrogen methods are being tested, but in general there is a distinct lack of environmental friendliness to the gas production process that counteracts the emission-friendly usage in the vehicles themselves. To date, analysis is inconclusive as to whether en masse replacement of fossil fuel vehicles with fuel cell equivalents would reduce greenhouse gas emissions. Indeed, some reports claim they use three times the amount of electricity per vehicle than the equivalent battery-powered car!
In addition to the price of hydrogen, fuel cells use rare elements such as platinum, contributing to the production costs. But most importantly of all, how will the vehicle manufacturers resolve the chicken-and-egg issue of providing adequate infrastructure when there is only a small customer base? Without enough refuelling stations and repair depots, most regions are unlikely to attract new customers, but how can a corporation afford to put these facilities in place before there is a demand for them? Most private vehicle owners would require an immediate advantage to migrate to the new technology, regardless of any environmental benefit. Unlike the early days of the internal combustion engine, fuel cell vehicles do not offer the paradigm shift that the automobile had over the horse-drawn carriage.
So with continuous improvements in battery technology, is there in fact any need for the fuel cell vehicles? Aren't electric cars the best alternative to the internal combustion engine? If so, wouldn't it make more sense to concentrate on battery development and not waste effort on a far from optimal alternative that might turn out to be a dead end? Perhaps this is a case of corporate bet hedging. After all, the telecommunications industry was taken completely unawares by the personal consumer demand for mobile phones - a device that was aimed squarely at business users - so this may be a Plan B if something happens with the growth of electric vehicles. At least vehicle manufacturers aren't anti-innovation this time, unlike their voracious gobbling up of advanced steam car development in the early 1970s.
If not for private road vehicles, could there be a future for fuel cell technology in public transport? China and some European nations such as Germany have been trialling hydrogen-powered buses and tram cars, whilst Boeing is one of the aircraft manufacturers investigating the use of fuel cells in small aircraft and unmanned aerial vehicles. That isn't to say the future of commercial air travel excludes the turbofan engine; fuel cells will probably only ever be used for auxiliary power units.
I wouldn't want to disparage innovation but can't help thinking that in this instance, the self-regulating capitalist model is failing to cope with the paradigm shifts required to face the challenges of climate change. Would it be better for governments to incentivise the front-runner replacements for environmentally poor technologies, in this particular case favouring electric-powered vehicles? Solutions are needed now and I'm just not sure that there is the time to solve all the issues surrounding hydrogen fuel cells and the necessary infrastructure. Perhaps this technology should be saved for a rainy day sometime in the future, once our current crises are over and dealt with?
Road vehicles of all sorts have had more than their fair share of ups and downs, not least due to the conservatism of that unholy alliance between the internal combustion engine and fossil fuels sectors. Although there were hydrogen-powered test vehicles in 1970s, it wasn't until 1991 that the development phase was completed. There are currently three car manufacturers with fuel cell models intended for personal customers: the Honda Clarity, Hyundai Nexo and Toyota Mirai. The latter two are intended to enter to take off (not literally) across South Korea and Australia respectively over the new few years, apparently selling at a loss on the assumption of beating rivals Nissan and BMW into the market. Brand loyalty being what it is, and all.
So what do fuel cell vehicles have that makes them a credible alternative to gas guzzlers and electric cars? Their primary benefit in this time-poor age is that they take only minutes to refuel – and with a range considerably greater than that of electric vehicles. Even so, this is hardly likely to be a convincing argument for petrol heads.
To anyone with even a vague knowledge of interwar air travel, hydrogen brings to mind the Hindenburg and R101 disasters. The gas is far from safe in large quantities, hence the rapid end of airship development; even with helium as a substitute, today's airships are smaller, specialist vehicles, their lack of speed making them an unlikely substitute for passenger jets. Although fuel cells themselves provide a safe power source, large quantities of hydrogen needs to be transported to the refuelling stations. A neat solution is to transport it in the form of ammonia (admittedly hardly a pleasant substance itself) and then convert it to hydrogen at the point of use.
What is less easily resolved is the cost of manufacturing the gas and the resulting high price for the customer. Most of the world's hydrogen is produced from natural gas; it can be made from renewable sources, but only at much greater expense. Wind-to-hydrogen methods are being tested, but in general there is a distinct lack of environmental friendliness to the gas production process that counteracts the emission-friendly usage in the vehicles themselves. To date, analysis is inconclusive as to whether en masse replacement of fossil fuel vehicles with fuel cell equivalents would reduce greenhouse gas emissions. Indeed, some reports claim they use three times the amount of electricity per vehicle than the equivalent battery-powered car!
In addition to the price of hydrogen, fuel cells use rare elements such as platinum, contributing to the production costs. But most importantly of all, how will the vehicle manufacturers resolve the chicken-and-egg issue of providing adequate infrastructure when there is only a small customer base? Without enough refuelling stations and repair depots, most regions are unlikely to attract new customers, but how can a corporation afford to put these facilities in place before there is a demand for them? Most private vehicle owners would require an immediate advantage to migrate to the new technology, regardless of any environmental benefit. Unlike the early days of the internal combustion engine, fuel cell vehicles do not offer the paradigm shift that the automobile had over the horse-drawn carriage.
So with continuous improvements in battery technology, is there in fact any need for the fuel cell vehicles? Aren't electric cars the best alternative to the internal combustion engine? If so, wouldn't it make more sense to concentrate on battery development and not waste effort on a far from optimal alternative that might turn out to be a dead end? Perhaps this is a case of corporate bet hedging. After all, the telecommunications industry was taken completely unawares by the personal consumer demand for mobile phones - a device that was aimed squarely at business users - so this may be a Plan B if something happens with the growth of electric vehicles. At least vehicle manufacturers aren't anti-innovation this time, unlike their voracious gobbling up of advanced steam car development in the early 1970s.
If not for private road vehicles, could there be a future for fuel cell technology in public transport? China and some European nations such as Germany have been trialling hydrogen-powered buses and tram cars, whilst Boeing is one of the aircraft manufacturers investigating the use of fuel cells in small aircraft and unmanned aerial vehicles. That isn't to say the future of commercial air travel excludes the turbofan engine; fuel cells will probably only ever be used for auxiliary power units.
I wouldn't want to disparage innovation but can't help thinking that in this instance, the self-regulating capitalist model is failing to cope with the paradigm shifts required to face the challenges of climate change. Would it be better for governments to incentivise the front-runner replacements for environmentally poor technologies, in this particular case favouring electric-powered vehicles? Solutions are needed now and I'm just not sure that there is the time to solve all the issues surrounding hydrogen fuel cells and the necessary infrastructure. Perhaps this technology should be saved for a rainy day sometime in the future, once our current crises are over and dealt with?
Monday, 29 October 2018
Space is the place: did life begin in the cosmic void?
A few weeks' ago I was watching a television documentary about the search for intelligence aliens and featuring the usual SETI experts Jill Tarter and Seth Shostak when I realised that we rarely see any crossover with research into non-intelligent extra-terrestrial life. Whereas the former is often seen by outsiders as pie-in-the-sky work by idealistic dreamers, the latter has more of a down-to-Earth feel about it, even though it has at times also suffered from a lack of credibility.
Based on current thinking, it seems far more probable that life in the universe will mostly be very small and entirely lacking consciousness, in other words, microbial. After all, life on Earth arose pretty much as soon as the environment was stable enough, around 3.7 billion years ago or even earlier. In contrast, lifeforms large enough to be visible without a microscope evolved around 1 billion or so years ago (for photosynthetic plants) and only about 580 million years ago for complex marine animals.
The recent publicity surrounding the seasonal variations in methane on Mars has provided ever more tantalising hints that microbial life may survive in ultraviolet-free shelters near the Martian surface, although it will be some years before a robot mission sophisticated enough to visit sink holes or canyon walls can investigate likely habitats. (As for the oft-talked about but yet to be planned crewed mission, see this post from 2015.)
Therefore it seems that it is worth concentrating on finding biological or pre-biological compounds in extra-terrestrial objects as much as listening for radio signals. The search can be via remote sensing (e.g. of molecular clouds, comets and asteroids) as well as investigating meteorites - bearing in mind that the Earth receives up to one million kilogrammes of material per day, although less than one percent is large enough to be identified as such.
The problem is that this area of research has at times had a fairly poor reputation due to the occasional premature claim of success. Stories then become widespread via non-specialist media in such a way that the resulting hype frequently bears little relation to the initial scientific report. In addition, if further evidence reverses that conclusion, the public's lack of understanding of the error-correcting methods of science leads to disillusion at best and apathy at worst.
One key hypothesis that has received more than its fair share of negative publicity has been that of panspermia, which suggests not just the chemicals of biology but life itself has been brought to Earth by cosmic impactors. The best known advocates are Fred Hoyle and Chandra Wickramasinghe, but their outspoken championing of an hypothesis severely lacking in evidence has done little to promote the idea. For while it is feasible - especially with the ongoing discovery of extremophiles everywhere from deep ocean vents to the coolant ponds of nuclear reactors - to envisage microbial life reaching Earth from cometary or asteroid material, the notion that these extra-terrestrials have been responsible for various epidemics seems to be a step too far.
It's long been known that comets contain vast amounts of water; indeed, simulations suggest that until the Late Heavy Bombardment around four billion years ago there may have been far less water on Earth than subsequently. Considering the volumes of water ice now being discovered on Mars and the Moon, the probability of life-sustaining environments off the Earth has gained a respectable boost.
It isn't just water, either: organic compounds that are precursors to biological material have been found in vast quantities in interstellar space; and now they are being found in the inner solar system too. That's not to say that this research has been without controversy as well. Since the early 1960s, Bartholomew Nagy has stirred debate by announcing the discovery of sophisticated pre-biological material in impactors such as the Orgueil meteorite. Examination by other teams has found that contamination has skewed the results, implying that Nagy's conclusions were based on inadequate research. Although more recent investigation of meteorites and spectrophotometry of carbonaceous chondrite asteroids have supplied genuine positives, the earlier mistakes have sullied the field.
Luckily, thorough examination of the Australian Murchison meteorite has promoted the discipline again, with numerous amino acids being confirmed as of non-terrestrial origin. The RNA nucleobase uracil has also been found in the Murchison meteorite, with ultraviolet radiation in the outer space vacuum being deemed responsible for the construction of these complex compounds.
Not that there haven't been other examples of premature results leading to unwarranted hype. Perhaps the best known example of this was the 1996 announcement of minute bacteria-like forms in the Martian ALH84001 meteorite. The international headlines soon waned when a potential non-biological origin was found.
In addition to examination of these objects, experiments are increasingly being performed to test the resilience of life forms in either vacuum chambers or real outer space, courtesy of the International Space Station. After all, if terrestrial life can survive in such a hostile environment, the higher the likelihood that alien microbiology could arrive on Earth via meteorite impact or cometary tail (and at least one amino acid, glycine, has been found on several comets).
Unmanned probes are now replicating these findings, with the European Space Agency's Rosetta spacecraft finding glycine in the dust cloud around Comet 67P/Churyumov-Gerasimenko in 2016. Although these extra-terrestrial objects may lack the energy source required to kick-start life itself, some are clearly harbouring many of the complex molecules used in life on Earth.
It has now been proven beyond any doubt that organic and pre-biological material is common in space. The much higher frequency of impacts in the early solar system suggests that key components of Earth's surface chemistry - and its water - were delivered via meteorites and comets. Unfortunately, the unwary publication of provisional results, when combined with the general public's feeble grasp of scientific methodology, has hindered support for what is surely one of the most exciting areas in contemporary science. A multi-faceted approach may in time supply the answers to the ultimate questions surrounding the origin of life and its precursor material. This really is a case of watch (this) space!
Based on current thinking, it seems far more probable that life in the universe will mostly be very small and entirely lacking consciousness, in other words, microbial. After all, life on Earth arose pretty much as soon as the environment was stable enough, around 3.7 billion years ago or even earlier. In contrast, lifeforms large enough to be visible without a microscope evolved around 1 billion or so years ago (for photosynthetic plants) and only about 580 million years ago for complex marine animals.
The recent publicity surrounding the seasonal variations in methane on Mars has provided ever more tantalising hints that microbial life may survive in ultraviolet-free shelters near the Martian surface, although it will be some years before a robot mission sophisticated enough to visit sink holes or canyon walls can investigate likely habitats. (As for the oft-talked about but yet to be planned crewed mission, see this post from 2015.)
Therefore it seems that it is worth concentrating on finding biological or pre-biological compounds in extra-terrestrial objects as much as listening for radio signals. The search can be via remote sensing (e.g. of molecular clouds, comets and asteroids) as well as investigating meteorites - bearing in mind that the Earth receives up to one million kilogrammes of material per day, although less than one percent is large enough to be identified as such.
The problem is that this area of research has at times had a fairly poor reputation due to the occasional premature claim of success. Stories then become widespread via non-specialist media in such a way that the resulting hype frequently bears little relation to the initial scientific report. In addition, if further evidence reverses that conclusion, the public's lack of understanding of the error-correcting methods of science leads to disillusion at best and apathy at worst.
One key hypothesis that has received more than its fair share of negative publicity has been that of panspermia, which suggests not just the chemicals of biology but life itself has been brought to Earth by cosmic impactors. The best known advocates are Fred Hoyle and Chandra Wickramasinghe, but their outspoken championing of an hypothesis severely lacking in evidence has done little to promote the idea. For while it is feasible - especially with the ongoing discovery of extremophiles everywhere from deep ocean vents to the coolant ponds of nuclear reactors - to envisage microbial life reaching Earth from cometary or asteroid material, the notion that these extra-terrestrials have been responsible for various epidemics seems to be a step too far.
It's long been known that comets contain vast amounts of water; indeed, simulations suggest that until the Late Heavy Bombardment around four billion years ago there may have been far less water on Earth than subsequently. Considering the volumes of water ice now being discovered on Mars and the Moon, the probability of life-sustaining environments off the Earth has gained a respectable boost.
It isn't just water, either: organic compounds that are precursors to biological material have been found in vast quantities in interstellar space; and now they are being found in the inner solar system too. That's not to say that this research has been without controversy as well. Since the early 1960s, Bartholomew Nagy has stirred debate by announcing the discovery of sophisticated pre-biological material in impactors such as the Orgueil meteorite. Examination by other teams has found that contamination has skewed the results, implying that Nagy's conclusions were based on inadequate research. Although more recent investigation of meteorites and spectrophotometry of carbonaceous chondrite asteroids have supplied genuine positives, the earlier mistakes have sullied the field.
Luckily, thorough examination of the Australian Murchison meteorite has promoted the discipline again, with numerous amino acids being confirmed as of non-terrestrial origin. The RNA nucleobase uracil has also been found in the Murchison meteorite, with ultraviolet radiation in the outer space vacuum being deemed responsible for the construction of these complex compounds.
Not that there haven't been other examples of premature results leading to unwarranted hype. Perhaps the best known example of this was the 1996 announcement of minute bacteria-like forms in the Martian ALH84001 meteorite. The international headlines soon waned when a potential non-biological origin was found.
In addition to examination of these objects, experiments are increasingly being performed to test the resilience of life forms in either vacuum chambers or real outer space, courtesy of the International Space Station. After all, if terrestrial life can survive in such a hostile environment, the higher the likelihood that alien microbiology could arrive on Earth via meteorite impact or cometary tail (and at least one amino acid, glycine, has been found on several comets).
Unmanned probes are now replicating these findings, with the European Space Agency's Rosetta spacecraft finding glycine in the dust cloud around Comet 67P/Churyumov-Gerasimenko in 2016. Although these extra-terrestrial objects may lack the energy source required to kick-start life itself, some are clearly harbouring many of the complex molecules used in life on Earth.
It has now been proven beyond any doubt that organic and pre-biological material is common in space. The much higher frequency of impacts in the early solar system suggests that key components of Earth's surface chemistry - and its water - were delivered via meteorites and comets. Unfortunately, the unwary publication of provisional results, when combined with the general public's feeble grasp of scientific methodology, has hindered support for what is surely one of the most exciting areas in contemporary science. A multi-faceted approach may in time supply the answers to the ultimate questions surrounding the origin of life and its precursor material. This really is a case of watch (this) space!
Thursday, 11 October 2018
Sonic booms and algal blooms: a smart approach to detoxifying waterways
A recent report here in New Zealand has raised some interesting issues around data interpretation and the need for independent analysis to minimise bias. The study has examined the state of our fresh water environment over the past decade, leading to the conclusion that our lakes and rivers are improving in water quality.
However, some of the data fails to support this: populations of freshwater macro invertebrates remain low, following a steady decline over many decades. Therefore while the overall tone of the report is one of optimism, some researchers have claimed that the data has been deliberately cherry-picked in order to present as positive a result as possible.
Of course, there are countless examples of interested parties skewing scientific data for their own ends, with government organisations and private corporations among the most common culprits. In this case, the recorded drop in nitrate levels has been promoted at the expense of the continued low population of small-scale fauna. You might well ask what use these worms, snails and insects are, but even a basic understanding of food webs shows that numerous native bird and freshwater fish species rely on these invertebrates for food. As I've mentioned so often the apparently insignificant may play a fundamental role in sustaining human agriculture (yes, some other species practice farming too!)
So what is it that is preventing the invertebrates' recovery? The answer seems to be an increase in photosynthetic cyanobacteria, or as is more commonly - and incorrectly known - blue-green algae. If it is identified at all, it's as a health food supplement called spirulina, available in smoothies and tablet form. However, most cyanobacteria species are not nearly as useful - or pleasant. To start with, their presence in water lowers the oxygen content, so thanks to fertiliser runoff - nitrogen and phosphorus in particular - they bloom exponentially wherever intensive farming occurs close to fresh water courses. Another agriculture-related issue is due to clearing the land for grazing: without trees to provide shade, rivers and streams grow warmer, encouraging algal growth. Therefore as global temperatures rise, climate change is having yet another negative effect on the environment.
Most species of cyanobacteria contain toxins that can severely affect animals much larger than fresh water snails. Dogs have been reported as dying in as little as a quarter of an hour from eating it, with New Zealand alone losing over one hundred and fifty pet canines in the past fifteen years; it's difficult to prevent consumption, since dogs seem to love the smell! Kiwis are no stranger to the phylum for other reasons, as over one hundred New Zealand rivers and lakes have been closed to swimmers since 2011 due to cyanobacterial contamination.
Exposure to contaminated water or eating fish from such an environment is enough to cause external irritation to humans and may even damage our internal organs and nervous system. Drinking water containing blue-green algae is even worse; considering their comparable size to some dogs, it is supposed that exposure could prove fatal to young children. Research conducted over the past few years also suggests that high-level contamination can lead to Lou Gehrig's disease, A.K.A. amyotrophic lateral sclerosis, the same condition that Stephen Hawking suffered from.
What research you might ask is being done to discover a solution to this unpleasant organism? Chemicals additives including copper sulphate and calcium hypochlorite have been tried, but many are highly expensive while the toxicity of others is such that fish and crustacean populations also suffer, so this is hardly a suitable answer.
A more elegant solution has been under trial for the past two years, namely the use of ultrasound to sink the blue-green algae too deep to effectively photosynthesise, thus slowly killing it. A joint programme between New Zealand and the Netherlands uses a high-tech approach to identifying and destroying ninety per cent of each bloom. Whereas previous ultrasonic methods tended to be too powerful, thereby releasing algal toxins into the water, the new technique directly targets the individual algal species. Six tests per hour are used to assess water quality and detect the species to be eradicated. Once identified, the sonic blasts are calibrated for the target species and water condition, leading to a slower death for the blue-green algae that avoids cell wall rupture and so prevents the toxins from escaping.
Back to the earlier comment as to why the report's conclusions appear to have placed a positive spin that is unwarranted, the current and previous New Zealand Governments have announced initiatives to clean up our environment and so live up to the tourist slogan of '100% Pure'. The latest scheme requires making ninety percent of the nation's fresh water environments swimmable by 2040, which seems to be something of a tall order without radical changes to agriculture and the heavily polluting dairy sector in particular. Therefore the use of finely target sonic blasting couldn't come a moment too soon.
Our greed and short-sightedness has allowed cyanobacteria to greatly increase at the expense of the freshwater ecosystem, not to mention domesticated animals. Now advanced but small-scale technology has been developed to reduce it to non-toxic levels, but is yet to be implemented beyond the trial stage. Hopefully this eradication method will become widespread in the near future, a small victory in our enormous fight to right the wrongs of over-exploitation of the environment. But as with DDT, CFCs and numerous others, it does make me wonder how many more man-made time bombs could be ticking out there...
However, some of the data fails to support this: populations of freshwater macro invertebrates remain low, following a steady decline over many decades. Therefore while the overall tone of the report is one of optimism, some researchers have claimed that the data has been deliberately cherry-picked in order to present as positive a result as possible.
Of course, there are countless examples of interested parties skewing scientific data for their own ends, with government organisations and private corporations among the most common culprits. In this case, the recorded drop in nitrate levels has been promoted at the expense of the continued low population of small-scale fauna. You might well ask what use these worms, snails and insects are, but even a basic understanding of food webs shows that numerous native bird and freshwater fish species rely on these invertebrates for food. As I've mentioned so often the apparently insignificant may play a fundamental role in sustaining human agriculture (yes, some other species practice farming too!)
So what is it that is preventing the invertebrates' recovery? The answer seems to be an increase in photosynthetic cyanobacteria, or as is more commonly - and incorrectly known - blue-green algae. If it is identified at all, it's as a health food supplement called spirulina, available in smoothies and tablet form. However, most cyanobacteria species are not nearly as useful - or pleasant. To start with, their presence in water lowers the oxygen content, so thanks to fertiliser runoff - nitrogen and phosphorus in particular - they bloom exponentially wherever intensive farming occurs close to fresh water courses. Another agriculture-related issue is due to clearing the land for grazing: without trees to provide shade, rivers and streams grow warmer, encouraging algal growth. Therefore as global temperatures rise, climate change is having yet another negative effect on the environment.
Most species of cyanobacteria contain toxins that can severely affect animals much larger than fresh water snails. Dogs have been reported as dying in as little as a quarter of an hour from eating it, with New Zealand alone losing over one hundred and fifty pet canines in the past fifteen years; it's difficult to prevent consumption, since dogs seem to love the smell! Kiwis are no stranger to the phylum for other reasons, as over one hundred New Zealand rivers and lakes have been closed to swimmers since 2011 due to cyanobacterial contamination.
Exposure to contaminated water or eating fish from such an environment is enough to cause external irritation to humans and may even damage our internal organs and nervous system. Drinking water containing blue-green algae is even worse; considering their comparable size to some dogs, it is supposed that exposure could prove fatal to young children. Research conducted over the past few years also suggests that high-level contamination can lead to Lou Gehrig's disease, A.K.A. amyotrophic lateral sclerosis, the same condition that Stephen Hawking suffered from.
What research you might ask is being done to discover a solution to this unpleasant organism? Chemicals additives including copper sulphate and calcium hypochlorite have been tried, but many are highly expensive while the toxicity of others is such that fish and crustacean populations also suffer, so this is hardly a suitable answer.
A more elegant solution has been under trial for the past two years, namely the use of ultrasound to sink the blue-green algae too deep to effectively photosynthesise, thus slowly killing it. A joint programme between New Zealand and the Netherlands uses a high-tech approach to identifying and destroying ninety per cent of each bloom. Whereas previous ultrasonic methods tended to be too powerful, thereby releasing algal toxins into the water, the new technique directly targets the individual algal species. Six tests per hour are used to assess water quality and detect the species to be eradicated. Once identified, the sonic blasts are calibrated for the target species and water condition, leading to a slower death for the blue-green algae that avoids cell wall rupture and so prevents the toxins from escaping.
Back to the earlier comment as to why the report's conclusions appear to have placed a positive spin that is unwarranted, the current and previous New Zealand Governments have announced initiatives to clean up our environment and so live up to the tourist slogan of '100% Pure'. The latest scheme requires making ninety percent of the nation's fresh water environments swimmable by 2040, which seems to be something of a tall order without radical changes to agriculture and the heavily polluting dairy sector in particular. Therefore the use of finely target sonic blasting couldn't come a moment too soon.
Our greed and short-sightedness has allowed cyanobacteria to greatly increase at the expense of the freshwater ecosystem, not to mention domesticated animals. Now advanced but small-scale technology has been developed to reduce it to non-toxic levels, but is yet to be implemented beyond the trial stage. Hopefully this eradication method will become widespread in the near future, a small victory in our enormous fight to right the wrongs of over-exploitation of the environment. But as with DDT, CFCs and numerous others, it does make me wonder how many more man-made time bombs could be ticking out there...
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