Easy energy option
Steuart Campbell calls for the abandonment of renewable energy sources and, as an alternative, the reliance on nuclear power or “some extraterrestrial solution” (17 April, p 30). This is a pretty absurd proposition, in a number of ways.
Campbell states that increased energy efficiency usually increases demand. There is little basis for this claim. If my old car did 10 miles per gallon and my new one does 50 miles per gallon, I would not drive further or more often.
Using renewable methods of generating electricity can drastically reduce the amount of infrastructure needed to deliver power. Renewable methods are suited to short-distance delivery chains because they can be safe to be around and cheap to build. Home wind-power generators have been around for many years. Small-scale renewable energy sources are also a much more realistic solution for developing countries, because they do not require huge investment.
Conventional sources, on the other hand, are generally centrally sited and need lengthy power lines to deliver electricity to consumers far away. Nuclear and large-scale fossil-fuel power plants are pretty nasty things, so they have to be placed away from people’s homes, again lengthening the delivery route.
Campbell’s description of renewable energy sources as “medieval” is partially accurate. But there is a reason they, and we, are here to tell the tale. Nuclear power has not been around for a long time, and we have already had one accident that has damaged a huge area of the Earth and affected millions of people. Nuclear power may become safer in the future, but even as the risk of accident is reduced, the potential scale of disaster is still massive. In comparison, the danger from renewable sources is typically something like getting hit on the head by a broken wind-turbine blade.
Why invest in researching a high-tech extraterrestrial energy source when we can make such easy gains on Earth? Go for the low-hanging fruit, please.
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Campbell tells us that increased energy efficiency makes fuel cheaper, while energy from renewable sources increase the cost of electricity.
Excellent. The two factors will therefore cancel each other out and power prices will remain steady. We won’t need additional nuclear power or have the huge associated cost of storing nuclear waste for thousands of years, never mind the threat of a radioactive leak.
Unethical snip
Your piece repeating the claim that circumcision reduces the risk of HIV infection sorely ignores the ethical elephant (3 April, p 15). Infant circumcision (the underlying object of all such studies) is a non-consented surgery that many bioethicists and legal scholars now recognise as extra-legal if not medical battery. The better solution to sexually transmitted diseases is simply more responsible, hygienic, adult sexual behaviour.
Pre-emptive amputation, without proper consent, of healthy, protective, immunologically alert, highly innervated sexual tissue is atrocious science and worse ethics, even if a prophylactic benefit could be demonstrated.
In any case, the US, with the west’s highest per capita levels of HIV, and its highest percentage of circumcised males, is a striking meta-experiment already run: as putative prevention for any sexually transmitted diseases, circumcision here has been an abject failure.
Mouldy theory
I was intrigued and amazed by the enthusiastic response of your readers to reports of our study investigating the origins of “fairy circles” in the Namib desert (3 April, p 12).
I gather that many respondents, including some published subsequently (24 April, p 32), proposed fungi or mushrooms as the possible cause. Many proposals sent to me personally in the wake of the article also suggested fungi, so I thought I’d respond to say we did take this into account.
A microbiological study was done at the University of Pretoria on the fairy circles and published in 1982. The lead scientist, Albert Eicker, who has since retired, was himself a mycologist and obviously also saw the possible link.
The study found that the density of the microbial populations in the circles matched that of plants, being lowest in the central bare patch and highest on the more fertile edges. Anaerobic bacteria, which thrive without oxygen, had their highest densities in the bare patch.
Overall, the pattern of the soil fungus population closely resembled that of other dry areas. Eicker concluded that the study could not shed any light on the problem of the origin or survival of the bare patches.
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I can certainly support Pieter De Waal in his theory that the “fairy circles” were possibly caused by toxic ash (17 April, p 31).
Three years ago I had a large bonfire of papers and magazines in one corner of my meadow. After the fire, the pile of ash was 3 metres across and about 20 centimetres high in the centre. It rained shortly after, and the ash compacted down into a grey sludge about 1 centimetre thick.
Over time, the sludge weathered away leaving no visible trace. But while nothing has grown in that spot, around the perimeter grass and weeds grow twice as tall as they do in the rest of the meadow.
I have no idea what was in those magazines, but it sure was toxic and long-lasting. What do you publishers put in your paper?
Sleeping soundly
I feel you have overstated the problem of anaesthetic awareness (17 April, p 6). From the more than 50,000 anaesthetics that I have given, I have had only one patient complain of inappropriate awareness. All my patients are assessed for awareness after their operations.
I have worked in many hospitals in New Zealand, Australia, the UK, the US and Singapore. The incidence in all these hospitals has been similarly low but the index of suspicion nevertheless high. I am therefore puzzled by your claim that many incidents of awareness are unrecognised. If not by the patients, recovery staff, ward nurses and anaesthetists, then by whom?
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I recently listened to a BBC Radio 4 programme that described an electronic monitor and also one surgeon’s simpler technique. When he is using a muscle relaxant he puts a tourniquet around one arm of the patient until the drug is absorbed, then removes it.
If the anaesthetic begins to wear off, this arm will begin to twitch before the patient is aware, and more anaesthetic is given. If more muscle relaxant is needed then the tourniquet technique is repeated.
The big ideal
Charts titled “Ideal weight for men” and “Ideal weight for women” accompany your article on “busting” fat, but there is no explanation of the basis for believing that the ranges given are in fact ideal (10 April, p 44).
The fact that there are separate charts for men and women suggests to me that the charts are in error if, by ideal weight, one means weight most conducive to longevity.
A great deal of the older literature has depended on a wealth of measurements collected by the Metropolitan Life Insurance Company on the heights and weights of their insured patrons. Historical examinations of the correlations between height, weight and mortality did indicate different “ideal” ratios of weight to height in men and women, when all ages were lumped together.
However, when Reubin Andres of the US National Institute of Ageing separately analysed the data for subjects in different age decades, he found that ideal weights (those correlated with lower mortality) increased with age, and also that the ideal-weight ranges were the same for men and women of the same age.
The editor writes:
鈥� See also “Why our fears about fat are misplaced” by Paul Campos, 1 May, p 20.
Growth spurt
Although specialists in the field accept that the universe started off at some point in the past in a big bang followed by a finite expanding volume, they are at the same time debating whether the universe is now infinite or not (17 April, p 12).
Surely, once finite, always finite. I am not aware of any scientific mechanism that allows something to make that transition.
For the record
鈥� We reported that the new Morse code sign for @ would be dash-dot-dash-dot (24 April, p 7). As those familiar with Morse will know, this is the code for the letter c. In fact, the @ sign will be signalled dot-dash-dash-dot-dash-dot.
False economies
I fully agree with Mark Buchanan’s take on the “rationality” of economic theory (10 April, p 34). However, the idea that the type of market modelling described provides a viable alternative to the conventional theory seems somewhat misplaced.
Real economic investigation into agent behaviour should start with some hypotheses about the forces driving the agents. Sure, one can achieve reasonably impressive statistical results by tuning a model with sufficient free variables to price movements, but the likelihood of this telling you anything about what drives these movements is small.
A number of pursuits within economics 鈥� including attempts at explaining individual choice behaviour 鈥� have fallen into the trap of believing that if you have a statistical model that fits the data relatively well, you have achieved an economic rather than a statistical result.
Even if they do predict some market movements, the idea that they will show us “what economics is really made of” seems optimistic at best. They could of course still make you rich 鈥� if they work.
Fighting phobias
The breakthrough treatment for phobias noted in your article is nothing more than implosion therapy 鈥� where the patient is flooded with experiences of a particular kind until becoming either averse or numbed to them 鈥� which has long been a tool of behaviour therapists (10 April, p 16). The general consensus is that while implosion therapy can have excellent short-term results, it is poor at producing long-term desensitisation to stimuli that elicit fear or panic.
It should also be noted that yohimbe has also long been used to stimulate not the “fight or flight reflex” itself, but rather some of the physical correlates of anxiety, such as rapid pulse. In clinical trials, it has been shown that yohimbe triggers anxiety in some, but not all, subjects.
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In the 1970s John Grinder, professor of linguistics at the University of California Santa Cruz, and Richard Bandler, studying psychology and mathematics at the same university, began to identify complex patterns of language and behaviour.
They went on to create intervention programmes, one of which was a phobia cure. This benign process, based on association and dissociation techniques, offered the opportunity to clear a phobia without inflicting trauma. They found that the faster they ran the process, the more effective it became. Eventually called the fast phobia cure, because it could be effected in 30 minutes or less, it required only one session to clear a phobia without recourse to drugs, hypnosis or behavioural therapy.
Unfortunately this interesting field, now known as neuro-linguistic programming, does not seem to be taken into account when research is undertaken 鈥� although admittedly scientists working only with mice might have problems introducing dissociation techniques.