Then there were鈥�
So the Otago museum in Dunedin, New Zealand, has another Falkland fox (14 August, p 25). Could there be yet more?
Indeed there could, these being the two skulls, mandibles and skins that were collected by Charles Darwin on his voyage aboard the Beagle. One of these is a male from East Falkland Island; the second is a female from West Falkland, where the population was smaller. There are also two further skulls without mandibles as well as a separate mandible. All this is in the collections of the Natural History Museum, London.
Interesting positions
I was interested to read Pete Furness’s thoughts on potholing and the positioning of patients in MRI scanners (21 August, p 27). But he does some injustice to the ingenuity already shown by practitioners of magnetic resonance.
We regularly position patients prone (on their chest) to image the anterior chest wall or breasts. In that position, the patient’s breathing makes the spine move, while the region of interest remains stationary. In our quest to position extremities into the isocentre of the magnetic field we have developed the swimmer’s position (prone, one arm up, one arm down) and the Superman position (prone, both arms up).
In the relentless pursuit of scientific enlightenment, one group of selfless researchers in the Netherlands even mastered the missionary position in MRI (British Medical Journal, vol 319, p 1596), although I confess that this will have done little to address the problem of claustrophobia.
Switch-off memory
The two-year, 拢1 million collaboration to develop a combination radio that remembers where a CD stopped when switched off, described in your Cutting Edge column (21 August, p 22), sounds remarkably as if it is trying to reinvent the radio in my 7-year-old Volvo. This not only remembers where the CD was before being switched off, it will also return to that point after traffic news updates or after the tape player is used.
I hope that the research you describe was not a waste of resources for the collaborators, and that they have managed to come up with something else as well.
Barry Fox writes:
鈥� The original text addressed this point but key words were lost in the editing. Some car CD players can remember where they were when switched off, but car players are no use to blind people. While DVD and Mini Disc players can already do this too, books for the blind are published on CD. The Roberts designers could find no consumer CD players that memorise the stop point after the player has been switched off. If any readers know of an off-the-shelf consumer CD player that has this capability, we would be delighted to pass that information on.
Binge and drive
I read your cover feature on binge drinking with great interest, but there was one glaring omission from the article (21 August, p 28). Alison Motluk mentions that “the UK has the highest legal limit for drivers’ blood alcohol in Europe” but she doesn’t actually say what it is.
I can tell you: it is 80 milligrams per 100 millilitres of blood, the very level which she says is now defined as binge drinking. Surely this was worthy of comment, if not a headline: “UK drink-driving limit allows binge drinking 鈥� shurely shome mishtake?”
Letter
The article says that “it is difficult to fathom what drives people to drink to utter excess”. Assuming that “utter excess” is just the author’s loaded term for “drunk”, an assumption supported by the rest of the article, then I would venture that it is not difficult to fathom at all: it is fun.
Fishy advice
Reading the interview with Robert Lawrence I found it amazing to see him say that “fish 鈥� which is high in nutritional value 鈥� and ‘good fats’ are fine” (14 August, p 42). Surely, being so well versed in the dangers of meat consumption he would know how bad fish can be for human health.
Fish contains dangerous environmental pollutants, such as polychlorinated biphenyls (PCBs), methylmercury and dioxins 鈥� more so than other products, as the toxins dissolve easily in fish oil. These chemicals can harm the development of a fetus and increase the risk of cancer.
Concerns in the UK over their health dangers led the Food Standards Agency to issue a recommendation in June that fish consumption should be reduced. The only reason it wasn’t recommended that fish should be removed from the diet completely was because it was believed there were useful oils in it. Yet these oils, omega-3 and omega-6, can easily be found in more benign alternatives such as linseed oil.
And then there is the environmental cost of fishing. Trawlers comb huge volumes of the ocean, killing whatever they encounter 鈥� quite often whales and dolphins. And stocks of many commercial fish are at dangerously low levels. This has far-reaching effects, as fish are an integral part of the food chain.
Quite why anyone should think fish is fine to eat is beyond me.
Letter
Although I agree in principle with the idea of reducing meat intake, and the corresponding reduction in saturated fat, I am not so sure about Meatless Monday’s sound-bite promotion tactics.
The US Department of Health and Human Services initiative “Healthy People 2010” has the ambitious objective of cutting Americans’ intake of saturated fat by 15 per cent. But trying to achieve this by inspiring people to have a day a week without meat seems flawed.
I very much doubt that one day without a significant amount of saturated fat would have as much of a health benefit as reducing the daily intake by a few per cent. What’s more, it fails to take into account people’s reward system 鈥� the one that lets you be more gluttonous than usual following a period of abstention. A few hours with the average dieter will usually illustrate this thinking with a “Well, I didn’t have much for lunch so I can have鈥�”
Robots vs infants
No one expects a young child to pass a Turing test against an adult (21 August, p 22). Instead we have a series of tests and exams that are used to assess the child’s progress against a set of standards, culminating in a trade or professional qualification or university degree.
Why cannot similarly gradated tests and standards be applied to robots? For example, the robot team could be pitted against sides of under-7s, 9s, 11s, 13s, 15s, and so on, rather than having to go straight in at the top level.
Double whammy
I noticed an alarming link between Kate Ravilious’s article detailing how the melting of permafrost may cause a rapid disintegration of mountains (24 July, p 6) and Fred Pearce’s report on the important but uncertain role that clouds play in climate change (24 July, p 44).
If global warming has the power to cause mountains to disintegrate, even before permafrost temperatures rise above freezing, the effect will be seen across the globe: it will extend to the Himalayas and the Andes, and not be restricted to marginal zones. Massive episodes of physical erosion will lead to decreased height and steepness of mountains, which in turn will result in a reduction in chemical weathering. This will lead to reduced erosional drawdown of CO2, leaving more CO2 in the atmosphere, which in turn will further boost global warming and the extent of permafrost melting.
Such an alteration to the physical characteristics of mountains has the potential to alter rainfall patterns and the extent of clouds. With new climate models emphasising the importance of changes to clouds, the crumbling of mountains could play a hitherto unacknowledged part in boosting global warming. Could these positive feedback mechanisms initiate the converse of the northern hemisphere uplifts that led to global cooling 40 million years ago?
Radiation risk
As members of the Committee Examining Radiation Risks from Internal Emitters (CERRIE), we cannot accept your interpretation of the committee’s leaked report (17 July, p 12). The idea that “risk from exposure inside the body could be 10 times higher than is allowed for in calculating international safety limits” is a massive understatement.
CERRIE’s report identifies uncertainties at every stage of estimating risk. They cannot be picked at random, and their values must be multiplied. Uncertainties due to variation in internal distribution and retention, dose coefficients and the risk factors derived from Hiroshima cover at least three orders of magnitude. On top of that there are unknowns such as environmental dispersion and intake.
Crucially, are data on the effects of the bomb dropped on Japan relevant to internal exposures? Energy deposition can be so variable that, as the CERRIE report notes, “concepts of absorbed dose become questionable and sometimes meaningless”. The recent discoveries of radiation-induced genomic instability, the bystander effect and mini-satellite mutation bring further uncertainty.
Faced with these uncertainties in modelling we should look at real events. The persistent excess of leukaemia in the village of Seascale, near the UK’s Sellafield nuclear complex in Cumbria, is the most notorious. The current radiation risk model fails to account for it by a factor of 200; yet there is no credible alternative explanation other than that radiation is the cause. The sharp increase in infant leukaemia in several countries after Chernobyl has no confounding factors, and again the current risk model fails to account for it by a factor of several hundred. These phenomena are not explained by the CERRIE report.
Permanent piracy
The Technology Trends piece on video piracy provided some information which, while doubtless accurate, was also misleading (14 August, p 22). The final part of the article, and the graphic, appear to show that legislative methods are effective in stemming the flow of illegal music file-sharing. The graphic in particular is at fault in this respect. The Kazaa peer-to-peer (P2P) network is undeniably in decline, largely as a result of the efforts of the Recording Industry Association of America, but this cannot be assumed to apply to the entire market.
When a network, or a piece of P2P software, is targeted, its users will be scared off 鈥� but possibly only to move them on to other networks. Kazaa is the beneficiary of the decline of Morpheus, as Morpheus was of Napster. The new networks that rise up usually provide extra protection of users and any central authors. BitTorrent, possibly the next big thing, does not run any kind of centralised network at all.
It would have been far more informative to show the effect on the total downloads of all P2P networks.