Letter
On Thursday morning I read the article about the damage caused by condensation trails from high-flying aircraft. It recommended that aircraft fly lower to prevent them, even though this would increase the fuel burn.
That afternoon, as I sat in my cockpit flying at 37,000 feet on route from Britain to Belgium, I watched other aircraft near my level go past leaving no trails or very short ones lasting only a few seconds. Looking down several thousand feet into the levels suggested by the article, I could see several large, spread-out trails that were obviously persistent.
Thus if I had done as the article suggested I would have burnt more fuel and produced a longer-lasting trail. This situation is not uncommon, as flight at high level in the drier stratosphere can be less conducive to trails than flying in the wetter troposphere, depending on the temperature profile of the atmosphere on any given day.
Letter
鈥� Our research on the potential benefits of reducing aircraft cruise altitudes to minimise contrail formation was intended to identify a solution to a major problem caused by commercial aircraft. Contrails and cirrus clouds cool the atmospheric system by reflecting incoming solar radiation, but also absorb the infrared radiation emitted from the surface and lower atmosphere. It is thought that the infrared effect dominates so that cirrus and contrails act much like greenhouse gases and the net effect is that of warming the atmosphere.
Our research sought to analyse one potential policy option, which is to restrict the cruise altitude of aircraft to a level that minimises contrail formation. Contrail formation is dependent on both ambient temperature and humidity levels, therefore we corrected for seasonal variation in atmospheric conditions. Contrail formation is more likely during the winter than during the summer and thus the altitude restrictions we analysed assume a maximum level of 24,000 feet in the winter and as high as 31,000 feet in the summer.
An extended version of Bill Fuller’s letter appears on our website.
Stable but chock-a-block
I was heartened to read of NASA’s plan to establish a space station at the L1 Earth-Moon Lagrangian point, (26 October, p 7).
One of the benefits put forward for using that location was that it was a gravitationally stable point, allowing low energy transfers to other Lagrangian points. My only concern, other than the US’s reluctance to pay the cost, is: will this region be filled with a high density of dust, rock and pieces of comets? Since it is a gravitationally stable region, will it not act as a gathering place for such material? If so, would this be detrimental to the proposed station?
Are toxins kinder?
I read your article on William Coley’s fever treatment for cancer with great personal interest (2 November, p 54). Three years ago, at the age of 45, I was diagnosed with a malignant tumour in my left breast. Fortunately, it was small and treatment by surgery (lumpectomy), radiotherapy and tamoxifen appears to have been very successful. I am deeply grateful to the medical profession for their skill in curing me and for their support.
However, it has been at a cost. Surgery and radiotherapy made me very unwell for six months and the suppression of my immune system left me tired and vulnerable to infection for a further two years. The removal of lymph glands means that for the rest of my life I must take care never to injure or bruise my left arm, as it is now prone to severe swelling. The skin on my breast feels dryer and older than the rest of my skin and I have been left with internal breast tenderness from the radiotherapy, which I am told will never improve. Taking tamoxifen also increases the likelihood that I will suffer from cancer of the womb and deep-vein thrombosis.
I cannot help but feel that Coley’s treatment was much kinder to the patient than our current treatments. I am not naive enough to imagine that his toxins would be painless or without problems. However, a bout of fever seems to me vastly preferable to today’s alternative.
Wrist relief
You describe a cooling glove that stops athletes “hitting the wall” (26 October, p 22).
Seventy years ago, when I was a pupil at junior school, we had a tendency to rush around the playground on hot sunny days until we became too hot and our energy would flag. But it was common knowledge that we could cool off rapidly by running water from a cold tap over the inside of the wrists 鈥� where the blood vessels are near the surface 鈥� and quickly regain our energy for more running around.
Sometimes it seems like there is nothing new under the sun!
Radical writer
On Wednesday 15 August 1979, a letter appeared in the London Evening Standard. It read: “I wish to protest most strongly about everything. Henry Root, Park Walk, West Brompton.”
Henry was the chairman and chief executive of Henry Root Wet Fish Ltd. In the late 1970s he corresponded with the good, the great and the not so great. The political and social importance of his letters was such that they were collected together and published. The Henry Root Letters (Futura Publications, 1981) are available for study by historians, social scientists or anyone interested.
My Latin education (O level, 1975, failed) suggests the mysterious amazon.com book reviewer Henry Raddick (Feedback, 2 November) may be related to Root. Henry, if you see this 鈥� it’s good to see life isn’t over after wet fish.
Blowin' in the wind
Ed Douglas is generally correct to say “in the popular imagination mountains are indestructible” (2 November, p 31). However, some forty years ago Bob Dylan warned of this fallacy when he sang: “How many years can a mountain exist before it is washed to the sea?鈥� The answer, my friend, is blowin’ in the wind.”
Letter
I applaud the study regarding retinal changes in lab animals treated with monosodium glutamate. We need more unbiased studies related to the physical problems MSG causes.
As a clinician involved for the past 20 years in the evaluation and treatment of MSG-sensitive individuals, I have found that one of the easiest ways of evaluating the patient is the eye. Although my patients are mainly corporate types and athletes with mental and physical performance problems, extremely common complaints also include food poisonings and visual disturbances. In fact, one can make the diagnosis from across the parking lot in certain individuals.
I would be the first to admit that many of the MSG-associated symptoms could be attributed to other more commonly recognised traditional diagnoses. However, doctors are taught that multiple symptoms should be related to one disease process. But what happens with the typical MSG-sensitive patient is that multiple specialists misdiagnose multiple “idiopathic” diseases. As my teenage daughter would say: this is a “duh”.
Since glutamate is a known neurotoxin and is used routinely to kill portions of the brain in animal studies, wouldn’t it follow that cells other than nerve cells are compromised? And if various types of cells were affected, wouldn’t it follow that the symptoms related to MSG toxicity involve multiple organ systems? More unbiased research please.
Knowing your fate
While respecting Ken Green’s views about his own health misfortunes and his preference not to be forewarned about his heart condition, I would argue for a very different view (9 November, p 29).
If I knew I had only 5 or 10 years of healthy life left, that information would be priceless. I would have the chance to come to terms with all the things I wouldn’t have time to do and make sure I did the things that really mattered but was putting off. I would also carry out a proper review of my priorities and my financial planning, both of which would probably result in major changes to my lifestyle. I will certainly take the gene tests if they become available.
Benefits of biodiesel
Your article suggests that diesel fuel 鈥� including biodiesel 鈥� contributes more to global warming than petrol (2 November, p 9). I would like to point out that although biodiesel still releases soot and carbon dioxide into the environment, the process is “carbon-neutral”, meaning that only carbon absorbed during the fuel’s growth is released when it is burnt. This differs from the burning of fossil fuels, which upset the balance of the atmosphere and environment by releasing carbon that has been stored for millions of years in the Earth.
Additionally, the plant matter from which biodiesel is made can be grown anywhere with suitable conditions for plant growth. If there was a large-scale shift to this fuel it would provide jobs for many small farmers internationally, and the need to transport the fuel (and the associated environmental disasters) would be minimised.
All countries could become more self-sufficient as normal diesel engines can run on this fuel without conversion.
Contrail controversy
Your article on contrails from aircraft implies that these long trails of water vapour and ice increase global warming because they encourage the development of cirrus clouds, which in turn reflect large amounts of heat radiated by the Earth, heating the atmosphere (19 October, p 6). So aircraft should fly lower to prevent cirrus clouds forming.
But the following week, your article on cirrus clouds implies that when there are less cirrus clouds (as happened after 11 September when aircraft were grounded), more sunlight comes in, causing the daily temperature variation in the US to grow by up to 3 掳C (26 October, p 51). So do cirrus clouds (especially those formed by contrails) increase global warming or not?
How safe is glutamate?
People now ingest undetermined amounts of free glutamic acid in the flavour enhancer monosodium glutamate, in other ingredients and in fruits, grains and vegetables that have been sprayed with MSG as they grow. Glutamic acid as part of a protein has important nutritional value. Free glutamic acid, if injected or applied directly, is capable of killing brain cells.
Hiroshi Ohguro speculates that a diet high in glutamic acid might raise glutamic acid levels in the eyeball (26 October, p 11). Recent research has linked such rises to glaucoma. As New 杏吧原创 reported, Ohguro found that very large amounts of monosodium glutamate cause retinal damage in rats. There is no evidence that lesser amounts of monosodium glutamate over a lifetime won’t cause retinal damage in people, too.
The Truth in Labeling Campaign has observed that some MSG-sensitive people can eat a particular “fast food” on a single day without experiencing MSG-reactions 鈥� such as nausea, drowsiness and headaches. Yet when those same people eat that same fast food two or three days in a row, typical MSG-reactions occur.
The glutamate industry, in the form of the International Glutamate Information Service, responded to the New 杏吧原创 story with a press release and letters to the other media that reported the study, including one to New 杏吧原创 (16 November, p 24). Since 1969, the industry has been claiming that consuming glutamate is safe.
Yet a 1995 review by the Federation of American Societies for Experimental Biology concluded that MSG can cause adverse reactions in an “unknown percentage” of people. Virtually every migraine clinic in the US recognises monosodium glutamate as a potential headache trigger, for example.
The International Glutamate Information Service claims that accurate information about glutamate can be found at its website, . An alternative view can be found at www.truthinlabeling.org.