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Last week I was discussing the Test Achats ruling from the European Court of Justice with a couple of colleagues.  (For those interested it means that insurers won’t be able to set premiums based on a person’s gender from December 2012.)

Eventually this discussion rambled off topic and led to a surprising question from one of them: is a female defined as the sex in a species that gives birth?

As i explained, the answer is actually that the female is the sex with the larger gametes,  ie the sex that produces eggs rather than sperm.  However, there are some species which reproduce sexually but have sexes with equal sized gametes; they are isogamous.  These species have two or more sexes none of which is labelled “male” or “female”.

How does that work?  Well if you think of a species with three sexes (A, B and C) then each sex can reproduce with either one of the other two sexes.  This actually leads to evolutionary pressure to produce an ever greater number of sexes.  An organism of sex C can reproduce with 2/3rds of the other organisms.  It won’t be able to reproduce with sex C organisms as a wway to prevent self-fertilisation.  If, following a mutation, an organism arises that is a new sex (sex D) it will be able to reproduce with any other organism in its species as it will be the only sex D organism around.  Eventually, due to this advantage, the number of sex D organisms will rise until there is an equal proportion of each sex and there will be evolutionary pressure for a fifth sex to arise.  There are some species out there with hundreds of sexes with the number growing all the time presumably.

Thinking about this, what surprised me was that this isn’t a topic that was covered in my GCSE biology.  I’d read about it much later.  Yet I think it’s highly interesting, not too complex to understand and illustrates evolution in action.  All of which make me think that it’s something that should be taught.

Yesterday was Holocaust Memorial Day so it seems like a good moment to remember an extraordinary scientific study carried out by a group of doomed men and women in the Warsaw Ghetto.

Following the conquest of their allocated share (under the Molotov-Ribbentrop pact) of Poland the Germans annexed the prime agricultural areas with the remainder of conquered Poland forming the General Government.  This rump did not produce nearly enough food to feed the inhabitants and the Nazis were not particularly interested in doing much to alleviate this situation for their perceived racial inferiors.

As a result, by 1941 General Government was an area of hunger.  The Jews who were herded into the Warsaw Ghetto were the worst off, with daily food intakes well below starvation levels.  It was in these circumstances in late 1941 a group of doctors decided to study the effect of starvation on the people of the ghetto.

The study was the idea of Israel Milejkowski, the head of the Judenrat Health Department and carried out by a group of 28 Jewish doctors at hospitals within the ghetto.  Work was halted in July 1942 as the Nazis started deporting the residents of the ghetto en masse and further study became impossible.  During a temporary lull in the deportations, what data had already been gathered was collated and written up.

This information was then smuggled out to Professor Orlovski, chairman of the department of medicine at a university hospital outside the ghetto in Warsaw.   Orlovski was given instructions to have it published after the war if none of the researchers retrieved it.

One of the researchers, Dr Apfelbaum escaped the Ghetto in 1943, survived the war and after retrieving the manuscripts passed them on to the American Jewish Joint Distribution Committee.  He died shortly afterwards in 1946.  The majority of the other researchers did not live to see the end of the war.  The project’s instigator Israel Milejkowski was sent to the extermination camp at Treblinka.

Nevertheless they left behind a set of highly valuable and meticulously recorded scientific data.  Extraordinarily, the studies carried out by this small group of doctors were incredibly detailed and of very high quality despite the extraordinary conditions under which they worked.  Their studies were of a type that cannot normally be ethically carried out and as a result are still enormously valuable.  One of their findings was that the best way to treat starvation is to refeed people slowly.  Had this been known by the Allies, it could have saved the lives of many of those subsequently liberated from concentration camps.  These survivors were often given large amounts of food quickly, which proved fatal.

More information on the extraordinary people involved in this chapter of medical history can be found in “The uses of adversity: Studies of starvation in the Warsaw Ghetto” by Dr Leonard Tushnet.  Those of the records that survived have been published as a book under the heading “Hunger Disease: Studies by the Jewish Physicians in the Warsaw Ghetto”.

As a follow up from my previous post, I’ll link to this story on Engadget that was forwarded by a friend.  Broadly a bunch of audiophiles couldn’t tell the difference between a cable made from coathangers and a ludicrously expensive premium speaker cable.

Some google-fu also threw up this story, in which a review website carried out a blind test on power cables.  Result: they couldn’t tell the difference between generic power cables and premium power cables.

I have to respect this set of reviewers who carried out the blind test in response to some of their readers who didn’t believe an article extolling the virtues of a  power cable they had reviewed.  The reviewers went away and tested their beliefs and then reported back on their failure to hear any difference when using the expensive cables.

 

If all goes well, I will be the owner of a flat by the end of the month.  Fortunately it isn’t the flat purchase that is making me worry about wasted money (yet).  Instead, it is the relatively paltry £4.50 I spent on What Hi Fi magazine.

As I’ll be needing a TV for the flat, I was reading their feature covering the top TVs for 2011.  However my confidence in their advice was somewhat diminished when I came across a section reviewing different figure of eight cables.

Just to be clear these are power cables you might use to plug your Sky box into the mains.  In fact this is how they tested the cables, using each cable in turn to plug their Sky box into the mains and commenting on the perceived difference in audio/visual quality.  Of the six cables reviewed, prices ranged from £3.50  to £150 (the Furutech G-320Ag in case you were wondering).

I’m pretty sceptical that changing the cable will make any difference to your viewing – even if the cable is silver plated like the Furutech one.  For starters it isnt clear why a silver plated cable will work better than a plain copper cable – they’re both decent enough electrical conductors. Nor is it clear what a cable can be doing to the power supply to make the picture quality better (other than doing the very basics of making sure the electricity does indeed get to your TV).   Also, I doubt the power lines to your house and the wires running about inside your appliances are silver plated either so a measly couple of meters of silver plated cable in between is unlikely to make a difference.

I’m willing to be persuaded otherwise.  Perhaps if the reviewers at What Hi Fi can reliably show they can tell the difference between the cheapest cable and the most expensive one  just from the quality of the picture on their TVs, but without knowing which one is plugged in. Otherwise I’m going on the hypothesis that the differences in quality they wrote about were merely a form of placebo effect (one cable got rated 2/5 and another 5/5, with the cheapest cable getting the worst score and the most expensive the best).

All this rather makes me question whether their reviewers just imagine the differences between TVs and doesn’t really help me make my TV buying decision.

One of the big science stories recently was about US doctors and scientists infecting Guatemalan prisoners and mental patients with syphilis to carry out research.  This made me realise that scientific and medical ethics is something that I’ve neglected to really comment on.  I’ll be trying to rectify that and this post is part of that effort (although it doesn’t deal with anything as unethical as the Guatemalan experiments).

I’m currently reading “Phantoms in the brain” (by VS Ramachandran and Sara Blakeslee) and the description of the treatment received by one of Ramachandran’s patients had me pondering some questions about medical ethics.

The case involves a patient who Ramachandran diagnoses with Capgras syndrome.  This is a disorder in which a person believes that a close friend or relative has been replaced by an identical-looking imposter.  The patient in the book believes this of his parents following a head injury.

Having made his diagnosis, Ramachandran does not tell the patient “because I wasn’t sure how he’d react”.  However just a few pages later we read the following poignant passage:

“Arthur’s most serious problem, however, was his inability to make emotional contact with people who matter to him most – his parents – and this caused him great anguish.  I can imagine a voice inside his head saying, ‘The reason I don’t experience warmth must be because I’m not the real Arthur.’  One day Arthur turned to his mother and said ‘Mom, if the real Arthur ever returns, do you promise that you will still treat me as a friend and love me?'”

Given Arthur’s distress is it really ethical for his doctor not to reveal his diagnosis?  The news that there are others who share this problem with him could help ease that distress.

As we are not his doctor and don’t have access to the full facts of the case there is no way for us to know.  Nevertheless it would have been good if the book had answered this question for us rather than leaving us speculating.

Slightly late to this, but about a week ago the US press started carrying stories about some highly unethical experiments carried out in Guatemala.   US medical researchers infected Guatemalan prisoners and mental patients with syphilis (without their consent) and went on to test whether the then new wonder drug, penicillin, would cure them.

This has been covered in-depth over at science-based medicine, so I won’t go into too much detail here.

One thing that caught my attention was that John C Cutler was the lead researcher on the experiment.  Cutler went on to work on the infamous Tuskegee syphilis experiment, which ran into the ’70s.  This experiment tracked hundreds of poor black men with syphilis to study the long-term effects when the disease is left untreated.

The study started before the advent of antibiotics made effective treatment of syphilis possible.  An argument could be made that, given there was no effective treatment at the time, the study was not unethical at the start.  However my impression is that the subjects were never told that they had syphilis and therefore some men went on to infect partners who might have avoided infection had the men known of their infection.

Moreover this fig leaf of justification falls away completely once you realise the study went on for 25 years after penicillin became the standard treatment for syphilis.  Doctors and scientists lied to the men involved to prevent them receiving treatment.  Indeed the study only ended after a whistleblower went to the press to have the study stopped (after failing to persuade his superiors to do so).

Unbelievable Cutler was still defending the Tuskegee experiment into the 90s.  Since he is dead we can never know what justifications he would have come up with for the Guatemala experiments.  Looking back over his career one is forced to the conclusion that the only thing distinguishing Cutler from those who ended up swinging at the end of a noose in Landsberg prison was not his ethics but that he was born American.

We’re all used to reading about various dubious remedies where magnets are supposed to treat a variety of ailments.  It was therefore a refreshing change to actually hear about a treatment for cancer based on magnetism with genuine potential this weekend.

The venue was the Royal Institution, where, as part of Open House weekend, members of their interdisciplinary research group were talking about their work.  One of their projects is looking at trying to treat cancer with magnets.  In particular magnetic nanoparticles injected into you.

These nanoparticles are supposed to latch onto a tumour thanks to a coating of an enzyme that binds onto cancerous cells but not onto healthy ones.  The enzyme has to be tailored to the particular type of cancer.   The next step is to hold an electromagnet over the area with the tumour.

If you pass an alternating current through the electromagnet, then the north and south poles on the electromagnet will keep switching back and forth.  This in turn will alternately attract, then repel the magnetic nanoparticles near the tumour.  As the nanoparticles move back and forth they rub against each other and the friction causes them to heat up.  Get them hot enough (around 42 degrees celsius) and the cancerous cells should start dying.

Thanks to a rubbery model of a patient with nanoparticles injected just under an area on its surface I could see this heating effect on a thermal imaging camera when an electromagnet was brought close.  When the electromagnet was held over an area of the model with no nanoparticles under the surface there was no heating.

This is all rather clever.  At the moment the team at the RI is trying to develop nanoparticles that are stronger magnets.  This will potentially allow the therapy to be used on tumours deeper within the body.  They are also working on testing the idea to see if it makes the transition from promising idea to workable treatment.

Something pedlars of dubious magnetic therapies should consider doing before unleashing their quackery on the world.

Stumbling across news of the upcoming “Galileo Was Wrong” conference made me feel somewhat like Dr Watson in a Study in Scarlet who observes:

“My surprise reached a climax, however, when I found incidentally that he was ignorant of the Copernican Theory and of the composition of the Solar System. That any civilized human being in this nineteenth century should not be aware that the earth travelled round the sun appeared to be to me such an extraordinary fact that I could hardly realize it.”

The fact we are now in the 21st, rather than the 19th, century makes it even more extraordinary that there are people organising a conference dedicated to the idea that the Earth is at the centre of the universe.

Read the rest of this entry »

Periodically, Ray Kurzweil (author, inventor and machine intelligence pioneer) will pen an article or book making bold predictions about the future.  Recently Wired carried an article with quotes from him that suggested we will have reverse engineered the brain by 2030.

Kurzweil’s claims had biologists slapping their foreheads in irritation.  This post is not about Kurzweil.  It is about the biologists slapping their foreheads, or at least about some of the tangents the threads on their blogs took

Over at Pharyngula a discussion started up about the implications if we could create exact copies of ourselves.  Quantum mechanics has something to say about these speculations and maybe about how our brains work.

Read the rest of this entry »

The usual suspects at the Daily Mail are busily plugging the idea that eating berries (and walnuts) could stop Alzheimer’s.

Their story is based on work by Shibu Poulose who reported his findings to a meeting of the American Chemical Society.  The fact this was reported at a meeting or conference makes it sound rather as if Dr Poulose hasn’t published his research in a peer reviewed journal yet.  A quick search through Pubmed certainly fails to find any papers by Dr Poulose on the topic.

What the Mail didn’t tell you is that the research was carried out by feeding berries to rats.  Not humans.  At least over at the grown up papers the Telegraph did mention this fact but that isn’t stopping them from uncritically plugging the same story.

Depressingly the intrepid Dr Poulose is suggesting that people eat the whole fruit, which contain hundreds of health-boosting chemicals.  While the result sounds potentially promising, I’m not sure a rat study lasting a couple of months is enough evidence to be pontificating about what people should eat.  Perhaps you should be concentrating on getting this study published and then doing further work in actual humans first?

A final point of interest is the identity of the Telegraph journo covering this story.  Stephen Adams would appear to be their arts correspondant.  How did he end up covering a science/health story?

A Google search confirmed my suspicions and throws up a press release from the American Chemical Society.  All of which suggests the following journalism warning label should be plastered over the story:

Who?

Amit Ghosh does mathsy things for an actuarial firm. He read Physics at university, and they even let him loose in the Cavendish laboratory one summer on a research project. He is @bexleylister on Twitter.

Shona Ghosh read English, then did an MA in Journalism. She knows nothing about science. She wishes she did though, so she sometimes reads New Scientist and tries to make Amit explain quantum physics to her, preferably through the medium of pictionary. She is @shonaghosh on Twitter.

They combine their thoughts on this blog.

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