Defence of evidence
I was disappointed by your article “Between prison and freedom” (14 August, p 8 and p 5). I can state confidently that DNA profiling, regardless of public perceptions, is not “generally seen as infallible” by forensic science organisations.
DNA profiles may often be partial, or mixed (or possibly contaminated), but even obtaining a clear profile still only addresses the “source” question; “whose DNA is this likely to be?”
The second or “activity” question, “How and when did the DNA get to be on the exhibit or at the crime scene?” requires a detailed evaluation by Biology Reporting Officers. They are trained to estimate the appropriate “likelihood ratio” 鈥� the probability of the profile being found, given the prosecution’s proposition of events, versus the probability given the defence’s. While precise numbers may not always be possible, because of unquantifiable variables, if the evaluation cannot differentiate to a sufficient degree between the two propositions, it will state so in the court report.
In the UK, scientists have no incentive or vested interest in proving defendants guilty. All forensic DNA providers work independently of the police (unlike in the US) and all reports and evaluations are peer-reviewed.
Your statement that “little distinction is made, either in labs or in court, between samples of different quality: DNA is just DNA” is unfortunate. Any laboratory approaching DNA in such a cavalier way would fail its quality accreditation under and forfeit permission to upload profiles to the .
From Herzl Regev
Software packages to evaluate forensic results statistically should, as you say, be open source so that all labs can check them. Further, every test should be evaluated by each lab using several such packages, to avoid the possibility of a software bug skewing the results of all labs, leading to a wrongful conviction.
Beer Sheva, Israel
Nuclear perils
Wade Allison suggests we are being over-cautious in our safety limits for ionising radiation (31 July, p 24). He pursues the elusive idea that there could be a safe level of radiation for the human population. But his article conflates two different issues, one scientific and the other societal.
The best available scientific evidence, both epidemiological and laboratory research, was weighed up by the US National Academy of Sciences in a . This determined that the dose-effect relationship is linear down to the lowest doses such that there is no safe dose of radiation, only permissible doses.
How do you decide what level of additional health risk to the population should be permissible, given the rates of cancer from other causes in the population? Would that be 1 cancer per 100 exposed individuals or 1 cancer per million? There needs to be careful attention to the costs and benefits to society before recommending any increase to our radiation exposures.
From Roy Harrison
The suggestion that relaxing radiation exposure limits would lead to a large reduction in the cost of nuclear power is curious. Many costs, such as having three independent emergency cooling systems, are caused by the need to avoid breach-of-containment incidents, which can lead to a large tract of land being contaminated to a level not acceptable to Wade or anyone else.
The nuclear industry makes every effort to avoid such incidents, but then pretends that they could never happen and refuses to discuss the consequences of such breaches. It is obvious that they are possible. Apart from the infinite ingenuity of human beings to find exciting new ways of screwing things up, nuclear plants are not armoured sufficiently to protect against a military attack.
So many people will oppose nuclear power plant construction, having Chernobyl in mind, when the actual consequences may turn out to be orders of magnitude less serious than this 鈥� if they could be discussed.
Romsey, Hampshire, UK
Don't fear the fever
I was extremely interested in your discussion of the effects of fever (31 July, p 42). In 1996, while working in Germany on a cancer project at the University of Bremen, I stumbled on a 1951 paper by Louis Diamond and Leonard Luhby on spontaneous remission in childhood leukaemia (). They noted that a feverish infection preceded remission in 21 out of 26 children they studied.
I remember jumping up from my chair thinking this cannot be happenstance. I investigated many publications on spontaneous regression from cancer. Many, if not a majority, of cases were preceded by a feverish infection 鈥� see my 2005 paper in the .
Today we know that bacterial and viral chemicals such as lipopolysaccharides, which are strong inducers of fever, are needed to activate innate immune system 鈥� the body’s initial immune response which defends against pathogens in a general way without conferring immunity 鈥� and that this activation is needed to trigger a full-blown T-cell response against cancer cells.
Yet whenever I present these findings in medical circles, the reaction is blunt mistrust. For example, at a recent conference on innate immunity I listened to a talk that revealed that many more patients survive sepsis, a whole-body inflammatory response, if they develop fever. I asked whether it might be worth considering inducing fever in high-risk patients. I received a brief response: “No”.
The persuaders hide
In Australia, our 21 August election appears to have been totally driven by polls and focus groups. Reading your feature on neuromarketing (7 August, p 32), I wondered when political candidates might start using this kind of technique.
I was not reassured by the claim by Michael Smith at NeuroFocus that neuromarketing cannot be used to make us buy (or vote for) things we don’t want or need. What, then, is the point of measuring how people feel when looking at your cover? If customer satisfaction is the objective, why not measure how they feel while reading the articles?
Political candidates may not be able to sway voters who are locked into another party, but the results of research using electroencephalograph machines is likely to make it easier for them to persuade all those swing voters to vote one way or another on the basis of completely superficial issues.
From Stewart Johnson
When this issue arrived, the address sticker obscured the most striking part of the cover image selected through a neuromarketing experiment. This illustrates a basic contradiction in marketing reasoning.
In this case you sacrifice the quality available to loyal subscribers to entice the more impulsive readers who occasional buy it on the news-stand. Continuing this strategy would cause failure in the long run: you would end up producing a whiz-bang magazine (Lose weight! Attract sex partners! Get rich!) that lacks the substance to hold on to your intellectual base.
Williamstown, Massachusetts, US
From John Anderson
Some years ago, my 5-year-old son and I were watching a children’s film on TV. It stopped for an advertising break and, like most people, my son rushed out of the room for a drink, talking as he went. “Sssh” I said, “I want to watch this advert”. “Ha! That stuff’s no good”. “How do you know that?”, I asked. “Well, if it was any good, they wouldn’t have to advertise it, would they?”
Warsaw, Poland
Meat is morbid
It is extraordinary that you devoted so many pages to animal cloning while failing to acknowledge the suffering it causes (Instant Expert, 7 August).
About 20 per cent of cloned calves die during or shortly after birth, and an additional 15 per cent before weaning, according to the European Commission’s (EGE). Many are born with deficiencies such as malformed cardiovascular or pulmonary systems or low levels of immunity.
Furthermore, farmers are likely to use cloning to produce huge numbers of the highest-yielding meat and dairy animals, whose metabolisms are already stretched to breaking point. EGE has said that it has doubts whether cloning animals to supply food is ethically justified. Is it time to call a halt?
Row, row your boat
Your article on alternative rigging for rowing crews provided an interesting analytical take on a part of rowing which is often thought to be one of the dark arts (24 July, p 35).
It ignored, however, a major reason for not using many of the rigs illustrated in the article. This is that the torsional stresses induced on the hull by anything other than the conventional rig you describe will lead to performance-sapping flexing of the hull. This ultimately results in the hull going “floppy” and needing to be replaced sooner.
Top-flight racing boats cost up to 拢35,000 and can remain stiff enough for top-level domestic use for up to five years. This is therefore a significant concern.
Intended dissonance
Philip Ball’s article on the universality of music touches on the debate over a purported universal preference for consonance, quoting Josh McDermott as saying that some non-western cultures use what a westerner might consider “dissonant tuning” (8 May, p 30). This sometimes matches the special timbres of the instruments involved, such as those in a gamelan orchestra, which are very slightly out of tune with each other to produce what is considered a shimmering musical sound.
The obvious basis for the appeal of music is the human voice. One might dismiss that on the grounds that the voice should therefore be widely regarded as the pinnacle of music, but that does not follow. It is only necessary that whatever is instinctively the most musical is closer to the human voice than to most other naturally occurring sounds.
The human voice only makes one pitch at a time, but there are harmonics. A preference for consonance may therefore be a preference for one voice over many in discord. It would be interesting to analyse the pitches of two people talking “harmoniously”, in contrast to the same two arguing.