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Prakash appointed new CSIR chief Geyser-less hot showers Prof Yash
Pal THIS UNIVERSE |
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Cell phone safety ON October 23, Dr Ashok Agarwal, from The Cleveland Clinic, presented a paper titled “Relationship between cell phone use and human fertility: an observational study” in a poster session at the 62nd annual meeting of the American Society for Reproductive Medicine at New Orleans. Physicians in Cleveland and New Orleans and Mumbai studied 364 men undergoing tests at a fertility clinic. They claimed that those who used mobile phones for more than four hours a day had significantly lower sperm counts than those who used them for less time. They also found significant differences in the mobility, viability and morphology of the sperms between the groups. The news received undue publicity as the finding was provocative. “On the face of it, the findings seem pretty robust but I can only assume that mobile phone use is some kind of surrogate for something else”, Dr Allan Pacey, at the University of Sheffield told The Times “If you are holding it up to your head to speak a lot, it makes no sense it is having a direct effect on your testes” he clarified. We know that other life-style factors affect sperm quality. Heavy users may spend more time sitting in cars. Their testes may warm up. Sperms are sensitive to heat. An association between mobile phone use and sperm counts may not be a causal link. Studies on mobile phone safety have been inconclusive. “There have been allegations in the media and in the courts that cell phones and other types of hand held transreceivers are a cause of cancer”, Dr J.E.Moulder and other researchers wrote in the Radiation Research (1999) Journal. “Overall, the existing evidence for a causal relationship between radiofrequency radiation from cell phones and cancer is found to be weak to nonexistent”, the authors concluded after an extensive review of literature. Dr Frumkin and other researchers concurred with the conclusions of the US Food and Drug Administration Center for Devices and Radiological Health that if there is a risk from these products — and at this point we do not know that there is — it is probably very small (CA Cancer J Clin. 2001) In December, 2005, the World Health Organisation (WHO) concluded that recent epidemiological studies have found no convincing evidence of an increased cancer risk or any other disease with mobile phone use. If we use mobile phones close to some medical devices such as pacemakers, it may interfere with their operation, the agency cautioned. WHO assured that changes in brain activity, reaction times and sleep patterns reported by scientists are minor and have no apparent health significance. According to the agency more studies are underway to confirm these findings. Christine Gorman, the columnist of the Times on line is not worried about the reported “cell phone use — low sperm counts” linkage. Firstly, she is a woman. Secondly, she spent half an hour with Dr Agarwal who answered questions non-stop for the last two days on his cell phone! “I am not giving up my cell phone” he confided to Ms Gorman. She says that he may get a new phone; his phone stopped working and had to borrow some one else’s to talk to all the journalists from around the world who are calling him up! I found that excess cell phone use is of no consequence to Dr Agarwal who is 50 plus! You may have some concerns over cell phone safety, but you need not lose sleep worrying over it; its harmful effects, if any, have not been conclusively confirmed.
Prakash appointed new CSIR chief The Mysore-based Central Food Technological Research Institute Director Dr V. Prakash has been appointed Director-General of the Council of Scientific and Industrial Research
(CSIR) with effect from January 1, 2007. He will hold concurrent charge as the
Secretary, Department of Scientific and Industrial Research, Union Science and Technology Ministry. Addressing a press conference here, Dr Prakash said he would be proceeding to New Delhi today to work for a month with Dr R.A. Mashelkar, the outgoing Director-General, as per the CSIR tradition. Dr Mashelkar had a record of splendid achievements for eleven years. “I want to understand the agenda set by him as my priority and carry on, more so in the context of the coming eleventh five-year plan,” he said. Recalling his nearly three-decades-long association with the
CSIR, Dr Prakash thanked the Union Government for having confidence in his abilities and said he would do his best to live up to the expectations of the authorities.
— UNI
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Geyser-less hot showers Thermoplastic used for the manufacture of these showers is an insulating material and allows no current to pass through it. Thermoplastic can also withstand high temperatures and there is no chance of its getting rusted. An electric hot shower needs 4400 watts or more of power, to be switched on for 10 minutes before use. The heating coil comes on only when water is released through the shower. Overall energy consumption works out to be one half of that consumed by a geyser of 1500 Watts. These showers are provided with multi-temperature controls to supply hot water or lukewarm water as per requirement of the consumer. There is provision of a residue blocking net in these showers. This net doesn’t allow any residue to enter the showers and can be easily detached and cleaned whenever required.
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THIS UNIVERSE Why do electrons keep going around the nucleus of the atom instead of keeping stationary
in their place? When Neils Bohr first gave a model for the atom he could not keep the electron stationary in any special place, because he could not overlook the requirement that the attractive force between a negative electron and a positive nucleus had to be balanced. This could be done by the centrifugal force of a revolving electron. But then he realised that an orbiting electron would emit electromagnetic radiation and loosing energy it would spiral down onto the nucleus. He had to make the hypothesis that the orbits of the electron were of a special “stationary” character and while they are in those orbits they would not emit any radiation. The energies of these orbits were assigned through invoking the quantum hypothesis. Today this model, while being of great historical importance, has been replaced by a picture where we do not think in terms of classical ball-like electrons, and fixed positions of orbits, but basic dynamics cannot be overlooked. No, we just cannot put an electron and a nucleus at fixed positions relative to each other and make them stay there. I have received a question: “What happens when sheets of paper, long rolled up into a tube, are unrolled but
simply won’t ever lie flat again?” Before answering I decided to check if there was any thing on this on the Internet. I was surprised to find that there was a question (with an answer) that read: “What happens when sheets of paper, long rolled up into a tube, are unrolled but simply won’t ever lie flat again?” There is no doubt that the questioner did not discover this question but sent it to me to find out if I was clever enough to tackle it! The question is nice but the practice of doing such things is a bit unfortunate. I like to answer your own discovered questions and not become a contestant in a quiz contest, particularly because I have several times declared that I do not know all the answers but would only like to share with you a way of thinking. Coming back to the question that has been asked, I would first draw your attention to the way in which paper is prepared. You take some shavings of wood, some old paper, some rags and various kinds of fibrous organic material and some water. Put these in a blender and after you are done use a mesh to lift some of the gooey material and let it dry. There are some physical or chemical processes that might be used but in the last analysis paper is just a lot of entangled fibers of cellulose. It is held together, has some strength and structure, because of Wet paper has no strength because water acts as a lubricant between the fibers - they can shift and twist. Small shifting and twisting can also be produced if we apply a differential force between different layers of paper. Such twisting can result in an altered pattern of fiber inter-connections. When we roll a sheet of paper around a tube we are introducing such a twisting by applying force. These changes, resulting from altered connections between fibers, acquire a semi-permanent character that persists till an opposite force is applied. It is not surprising, therefore, that after unrolling from a tube the paper insists on curling up till it is rolled up in the opposite direction. If we humidify the paper environment and use a warm iron to press it we will loosen the bonds between the fibers and easily press them back to give the paper its original flat shape. Indeed, this process is similar to that we use to iron out the wrinkles from our clothes. |
WITH an aim to dispense with costly geysers and avoiding botheration of their installation, engineers have invented geyser-less hot showers which can discharge water at desired temperature. Electrically operated, these showers are declared fully safe as a grounding system is provided with them that sends the leakage current, if any, to the ground and the users remains safe from