Tuesday, August 26, 2008
Internet hoax reaches Mars
August 26, 2008
By Syed Akbar
Hyderabad, Aug 25: An internet hoax that Planet Mars will appear as big and bright as the Moon on August 27 is flooding email messages in the city, creating a sort of scientific sensation.
Thousands of netizens in Hyderabad and other parts of the country have received email messages on the "spectacular celestial phenomenon" that will repeat only after 60,000 years. As enthusiast net users gear up to witness the phenomenon, astrophysicists debunk it as yet another internet hoax.
Presently Mars is away from the Earth after coming closer to it during December last year. However closer Mars may come to the Earth, it will never appear like the Moon. This is because Mars is farther away from the Earth than the Moon.
Every August the hoax about the Mars appearing like the Moon is circulated to keep the myth alive. This has been going on since August 2003, when the Mars came closer to the Earth.
Along with the Mars hoax, other internet hoaxes that have doing the round in
email boxes in Hyderabad are about a "fiery rainbow" in the skies in Canada,
a human tree in Nalgonda and the miraculous survival of two girls buried alive by their cruel father in Egypt.
"This month and next, Earth is catching up with Mars in an encounter that will culminate in the closest approach between the two planets in recorded history. The next time Mars may come this close is in 2287. Due to the way Jupiter's gravity tugs on Mars and perturbs its orbit, astronomers can only be certain that Mars has not come this close to Earth in the last 5,000 years, but it may be as long as 60,000 years before it happens again," says the hoax email on the Mars.
About the "human tree" somewhere in Nalgonda district, the email hoax with pictures depicts a trunk covered with detailed images of many different creatures. The email claims that the tree is an example of an unknown species that grows in a dense forest in Andra Pradesh. "The tree is a completely natural living plant and that all of the animal figures on its trunk have mysteriously grown there naturally and without human interference," it says.
The most common hoax on internet is about some people in Africa who died after ants made their way into their brains. Another hoax is about the mysterious "Nareepol Tree" in Thailand that grows fruit in the shape of women. Yet another common hoax is that one can charge a mobile phone battery by touching the stems of peepal tree leaves to the terminals.
Monday, August 25, 2008
Suffering from diabetes? Eat fruits and vegetables
August 25, 2008
By Syed Akbar
Contrary to common belief that fruits will enhance the blood sugar levels and aggravate the health problems associated with diabetes, a team of scientists from the United Kingdom has found that a greater intake of fruits and vegetables will in fact decrease the risk of diabetes.
The UK research study showed that a higher plasma vitamin C level, and to a lesser extent fruit and vegetable intake, were associated with a decreased risk of Type 2 diabetes that commonly affect the adults. People suffering from Type 2 diabetes need not take insulin injections as against those suffering from Type 1 or insulin-dependent diabetes. Fruits and vegetables seem to work wonders in the case of "sugar" patients with Type 2 diabetes.
The results of the study gain significance from the fact that it was one of the long drawn research studies spanning about 12 years. More than 20,000 people, both men and women, were studied as part of the research.
The scientists established a strong, inverse relationship between plasma vitamin C level and the risk of developing diabetes. "The potential risk of developing diabetes was 62 per cent lower for those in the top quintile of plasma vitamin C, compared with those in the bottom quintile. A similar association was shown between plasma vitamin C and diabetes in participants who had a haemoglobin A1c (higher sugar) level of less than 7 per cent.
A weaker inverse association was found between the intake of fruit and vegetables and the risk of diabetes," the study pointed out.
Since fruits and vegetables are the main sources of vitamin C, the study suggests that eating even a small quantity of fruits and vegetables may be beneficial and that the protection against diabetes increases progressively with the quantity of fruit and vegetables consumed.
In another study conducted by a team of researchers from the University of Georgia, the oldest state-chartered university in the USA, some of the most commonly used dried herbs and spices may help block the inflammation believed to drive diabetes and other chronic diseases.
The Georgia researchers tested extracts from 24 common herbs and spices and found that many contained high levels of inflammation-inhibiting antioxidant compounds known as polyphenols. "Liberal use of cinnamon will have a great impact on your health", says researcher James L Hargrove.
Ground clove and cinnamon have more potential to positively affect health,
he adds.
In yet another study a team from the University of Warwick found that eating broccoli could reverse the damage caused by diabetes to heart blood vessels.
Broccoli contains a chemical called sulforaphane which works wonders with the circulatory system. People with diabetes are up to five times more likely to develop cardiovascular diseases such as heart attacks and strokes. Both are linked to damaged blood vessels.
Sulforaphane recorded a 73 per cent reduction of molecules in the body called Reactive Oxygen Species. Hyperglycaemia (high blood sugar levels) can cause levels of ROS to increase three-fold and such high levels can damage human cells.
Friday, August 22, 2008
Boost to India's nuclear energy programme: New uranium-thorium reserves found in Chittoor, Warangal
August 22, 2008
By Syed Akbar
Hyderabad, Aug 21: Andhra Pradesh is now emerging as uranium-thorium hub of India with new reserves of these atomic minerals being unearthed in Chittoor and Warangal districts.
Uranium has already been found in Kadapa and Nalgonda districts while thorium reserves are noticed in Visakhapatnam, Prakasam and Nalgonda districts.
The latest finding of uranium-thorium in Manupatulagadda and Mallampalli areas of Warangal district and Allapakonta and Vembakam in Chittoor district makes Andhra Pradesh one of the important States, which will catapult India to nuclear energy age.
Researchers at the city-based Atomic Minerals Directorate have also noticed rare earth elements like Niobium along with iron, uranium and thorium in the middle Proterozoic sediments of Pakhal basin in Warangal district. The mineralisation occurs predominantly in brecciated quartzite of Mallampalli Group of Pakhal Supergroup.
"The Uranium-thorium-rare earth elements mineralisation in Pakhal Super Group has all features of the Iron breccia type mineralisation quite akin to Bayan Obo (niobium rare earth element) deposit of China. The brecciated Bayaram quartzites of Pakhal basin are high in iron content," says AMD explorers in their research study.
An analysis of the Pakhal quartzite shows high iron content (22 per cent ferrous oxide) with good concentration of Titanium (3.34 per cent titanium oxide) and Phosphorous (2.69 per cent in the form of Phosphorus pentaoxide). It also revealed uranium concentration of 0.022 per cent triuranium octaoxide and 0.31 per cent thorium dioxide.
AMD's team comprising UP Sharma, K Umamaheswara and Himadri Basu have presented the first account of uranium occurrence in conglomerate at the base of Satyavedu Formation of Upper Gondwana sediments of Palar Basin, near Allapakonta and Vembakam in Chittoor district.
Grab samples have analysed 38 ppm to 218 ppm equivalent triuranium octaoxide, 32 ppm to 232 ppm triuranium octaoxide with negligible thorium. Radioactivity in conglomerate is associated with chlorite, zircon and ferruginous material, they noted.
Tuesday, August 19, 2008
Hyderabad turning hotter: City temperature soars up by 4 degrees Celsius
August 19, 2008
By Syed Akbar
Hyderabad, August 18: Hyderabad is turning into a "hot" city with the average maximum temperature soaring up by a degree Celsius every 10 years.
The city's mean maximum temperature rose by four degrees from 25 degrees C in 1960s to 29 degrees C in the 1990s. It now hovers around 30 degrees Celsius.
According to the national environment atlas released by the Union Ministry of Environment and Forests, temperature in Hyderabad has been going up consistently in the last 40 years. Separate studies by the Botany department of Osmania University and the National Remote Sensing Agency have linked the increase in city temperature to increase in air pollution and built-up areas, coupled with reduction in the green cover.
The National Aeronautics and Space Administration of the USA has already warned that one degree increase in temperature will have delirious effect on the environment in the long run. In case of Hyderabad the increase in temperature was four degrees C in four decades.
The city's "hotter" temperature has already altered the pattern of the rainfall in the last three decades. Meteorologists, who have observed the monsoon patterns in Hyderabad, report an increase of 34 mm in average rainfall in two consecutive 14-year periods. This also explains the phenomenon of "sudden downpour" affecting the city life.
The OU's Botany department, which conducted the environment study, found that "high densities and shortage of greenery and open spaces have vastly contributed to this rise in temperature". Environmentalists call this variation in urban climate as urban heat island effect and Hyderabad is currently experiencing this phenomenon.
"Increase in temperature may not have a direct impact on people's health, though it may increase their monthly expenditure in the form of more power consumption through use of air conditioners, coolers and fans. High temperature does not mean high radiation. So people may not fear about their health, but should be more concerned
about their pockets," says senior environmentalist Dr K Purushottam Reddy.
The Union Ministry of Environment and Forests seeks to blame the increase in temperature also on unchecked vehicular pollution, besides vast spread of concrete jungle. "The State government needs to make necessary amendments to the Motor Vehicles Act, to enable spot checking of vehicles and fines for owners, who fail to pass tests for carbon monoxide, hydrocarbons and lead emissions, giving scope for participation of the Residence Welfare Association and the service stations, who are the main state holders. As a rule there is a need to restrict the supply of
permit petrol and diesel only to vehicles which have PUC certificate," suggests the Environment Atlas.
A separate study by the city-based National Remote Sensing Agency has found that Bengaluru had much less dispersion in vegetation compared to Hyderabad and New Delhi.
Moreover, results from correlation analysis by NRSA team suggested that as population density increased, the entropy of vegetation greenness decreased in Kolkata, Bengaluru, Mumbai and Hyderabad compared to Chennai and Delhi. This in other words means that as the density of population increased, the vegetation greenness became more concentrated in these cities.
Sunday, August 17, 2008
Indian History: Dravidians Came First
August 17, 2008
By Syed Akbar
Hyderabad, Aug 16: Dravidians are the modern representatives of the earliest settlers of the Indian sub-continent dating back to more than 60,000 years before present (BP).
A research study by the Anthropological Survey of India revealed that Dravidians along with tribes of southern and eastern region and those who speak Austro-Asiatic languages still harbour the genes that were inherited from the earliest settlers in India. This in other words means that Dravidians and certain tribal groups have been inhabiting the land for thousands of years now.
"The Last Glacial Maximum (period between 18,000 and 21,000 years ago) aridity and post LGM population growth mechanised some sort of homogeneity and redistribution of earliest settlers’ component in India.
The migration triggered by agriculture and associated technologies around 3,000 years before present, which might have marginalised hunter-gatherer, is coincidental with the decline of earliest settlers’ population during this period," Dr VR Rao, director of ASI, told this correspondent.
The "out of Africa" model postulating single "southern route" dispersal posits arrival of "Anatomically Modern Human" to Indian subcontinent around 66-70 thousand years before present. However, the contributions and legacy of these earliest settlers in contemporary Indian populations, owing to the complex past population dynamics and later migrations has been an issue of controversy.
The high frequency of mitochondrial lineage "M2" consistent with its greater age and distribution suggests that it may represent the phylogenetic (evolutionary) signature of earliest settlers. "Accordingly, we attempted to re-evaluate the impact and contribution of earliest settlers in shaping the genetic diversity and structure of contemporary Indian populations," he said.
This is the first time that an entire mitochondrial DNA lineage has been sequenced for a research study. Of the known Mitochondrial lineage in India, M2 with an estimated age of about 50,000 years is the oldest and largest in its class. The distribution of M2 is significantly more pronounced in southern part of India as compared to north.
The frequency of M2 among the Brahmin and Kshatriyas of Andhra Pradesh is not significantly different from that of other caste and tribal populations of the region. However, it is absent among the Brahmins and Kshatriyas of the northern states of India, while the frequency reaches nearly three per cent among other caste and tribal populations of the region.
He said the time depth and diversity of M2 lineage among the studied tribes suggested that the tribes of southern and eastern region along with Dravidian and Austro-Asiatic speakers of central India are the modern representatives of earliest settlers of India via proposed southern route.
Wednesday, August 13, 2008
Languages have no genetic basis, says CCMB
August 13, 2008
By Syed Akbar
Hyderabad, Aug 12: Languages have no genetic basis, says a research study by the city-based Centre for Cellular and Molecular Biology.
In an international study carried out by CCMB in association with the University of Tartu, Estonia, Universia di Pavia, Italy and the University of Cambridge, the researchers there was a "significant correlation between genetic variation and geography, rather than between genes and languages". This is other words means languages have no genetic basis.
"Human genetic diversity observed in Indian subcontinent is second only to that of Africa. This implies an early settlement and demographic growth soon after the first 'Out-of-Africa' dispersal of anatomically modern humans in Late Pleistocene. In contrast to this perspective, linguistic diversity in India has been thought to derive from more recent population movements and episodes of contact. With the exception of Dravidian, which origin and relatedness to other language phyla is obscure, all the language families in India can be linked to language families spoken in different regions of Eurasia," said Dr K Thangaraj, senior scientist with the CCMB.
Mitochondrial DNA and Y chromosome evidence has supported largely local evolution of the genetic lineage of the majority of Dravidian and Indo-European speaking populations, but there is no consensus yet on the question of whether the Munda (Austro-Asiatic) speaking populations originated in India or derive from a relatively recent migration from further East.
The research team analysed 35 novel complete mitochondrial DNA sequences from India which refine the structure of Indian-specific varieties of haplogroup "R". Detailed analysis of haplogroup R7, coupled with a survey of around 12,000 mitochondrial DNAs from caste and tribal groups over the entire Indian subcontinent, reveals that
one of its more recently derived branches (R7a1), is particularly frequent among Munda-speaking tribal groups.
More than one sixth of humanity currently lives on the Indian subcontinent. This population is spread across up to 40,000 endogamous and semi-endogamous culturally, linguistically, and socially differentiated groups. The majority of these groups or
populations are castes, but they also include nearly 500 'scheduled tribes' and 500 'scheduled castes'.
"Thus, the Indian subcontinent is an ideal region for studying the relationships between culture, geography and genes, and for developing interdisciplinary models concerning the demographic history of Homo sapiens or anatomically modern humans," he said.
It has been argued, that following the initial colonisation of Indian subcontinent, maternal gene flow from the west has been rather limited and largely restricted to the western states of contemporary India and Pakistan.
Consequently, the haplogroup richness of the Indian subcontinent appears to have formed in situ, and date back to some point in the later Pleistocene. Furthermore, this high level of genetic diversity may also be linked to the possibility that the South Asian population in the Pleistocene was demographically large in global terms.
Similarly, the Indian tribes speaking different Munda languages show generally the same mtDNA haplogroup composition as the Indo European and Dravidic groups of India. In contrast, the Y chromosomes of Indian and Southeast Asian AA speaking populations
share a common marker.
Monday, August 11, 2008
Consanguineous marriages prevent malarial deaths
August 11, 2008
By Syed Akbar
Consanguinity or marriage between close relation has always been associated with genetic disorders and high mortality rate in children born out of such wedlock. While geneticists world-wide are discouraging people from marrying their close relatives, a scientific study on the effect of consanguinity on malarial deaths reveals that this ancient practice, in fact checks mortality rate in places where malaria is highly endemic.
Incidentally, the he practice of consanguineous marriages is widespread in countries with endemic malaria. In these regions, consanguinity increases the prevalence of alpha thalassemia, which is protective against malaria. However, it also causes an excessive mortality amongst the offspring due to an increase in homozygosis of recessive lethal alleles. But when one measures the benefits of reduction in
overall malarial deaths against the genetic disorders, the practice of consanguinity has to be encouraged in malaria endemic regions.
The study was carried by a team of scientists at UAE University, Abu Dhabi. According to Mukesh M Agarwal, one of the researchers, they had selected a computer model of population growth and compared the sizes of inbred and outbred populations. The team obtained the survival likelihood for different alpha thalassemia genotypes.
"Human inbreeding enhances the speed of fixation of recessive and codominant alleles. Consequently, the elimination of recessive lethal alleles is increased by an excessive mortality of children in consanguineous populations.
However, an enhanced speed of selection of the codominant alpha thalassemia allele in such inbred populations increases the relative fitness against malaria. When
mortality from malaria is high, this increase in fitness could offset the loss of life resulting from inbreeding. Therefore, consanguinity augments the fitness of a population with endemic malaria through its effect on alpha thalassemia allele," the study pointed out.
When the death rate due to malaria is high, the net effect of inbreeding is a reduction in the overall mortality of the population. Consanguineous marriages may increase the overall fitness of populations with endemic malaria.
Interestingly, marriages between close biological relatives account for up to 60 per cent of all marriages in many parts of Asia, Middle East and Africa. A common finding among consanguineous populations is their long history of exposure to malaria. In fact, the frequency and degree of consanguineous marriages correlates with the geographic distribution and intensity of Plasmodium falciparum in the population.
Alpha thalassemia has become the most common monogenic disorder in humans potentially because it decreases the probability of death from infection with P. falciparum.
The UAE team restricted their study model to exclusively large populations as the effect of inbreeding on the selection of recessive and codominant alleles is significantly less in smaller populations.
Additionally, when malaria emerged as an epidemic infection 4,000 to 10,000 years ago, the agrarian revolution had already caused a population explosion, an epidemiological pre-requisite for the appearance of malaria as an epidemic infection.
Mortality from Plasmodium falciparum is the highest in the first five years of life and it decreases with subsequent infections. During a single epidemic, malaria can kill up to 50 per cent of a susceptible population.
When the mortality from malaria is low, consanguinity depresses the population with alpha thalassemia by causing an excessive number of deaths via recessive lethal alleles and by negligibly retarding the selection of alpha thalassemia allele.
"More consanguineous marriages should be encouraged to take place among alpha thalassemia-carrier families. Even in non-carrier families, consanguinity may not be discouraged despite its genetic dangers (like childhood deaths and increased congenital malformations). This is because for any specific morbidity to be noticed, the difference from the reference (non-consanguineous, in this case) has to be sufficiently higher than five per cent, but is generally much below this threshold,"
he said.
The UAE study also corroborates findings from India which has over 50,000 brotherhoods and the frequency of alpha thalassemia is higher in tribal than in city populations. In the pas, when human survival became adversely affected by malaria, intra-family unions resulted inbetter survival of the offspring.
"In our globalised world with greater than ever mixing of populations, diseases like tuberculosis and AIDS are still the leading causes of death. Protection against both is provided by codominant and recessive alleles, whose selection could be accelerated by inbreeding," the scientists suggested.
AIIMS classes on sex for the unmarried
August 11, 2008
By Syed Akbar
Hyderabad, Aug 10: Getting ready for the marriage? Enrol with the All-India Institute of Medical Sciences for an exclusive two-day training course in sex education for a happy married life.
The India's premier medical and research institute has decided to conduct a pre-marriage training course for happy married life in a bid to keep the youth away from sex quacks and so-called sex specialists, whose ill diagnosis is leading to a spurt in HIV and broken marriages.
This incidentally is the first-ever sex education course, for people planning to marry shortly, being offered by a recognised medical body in the country. What's more, the participants will get a certificate from the AIIMS. However, those already married are barred from the admission.
The course is presently conducted at AIIMS campus in New Delhi and will be gradually extended to all medical colleges across the nation.Admission to the sex education training course is on first-come-first-served basis. The curriculum is exclusively designed keeping in mind the sexual and marital needs of the present generation of Indians, both men and women.
"It is a scientifically designed training course meant for people above 18 years. We are giving preference to those who are planning to marry soon. The curriculum includes human and sexual anatomy, sexual functions, sexual problems and their solutions, contraception, common sexual problems and sexually transmitted diseases including HIV/AIDS, besides expert medical advice on screening for genetic
diseases and making adjustments in married life," Dr Bir Singh, professor of community medicine, AIIMS, told this correspondent.
He said the AIIMS had taken up he course in view of high incidence of marital discord and sexual disharmony and increase in HIV/AIDS and STD cases among young couples in the country.
"Apart from stress in general life, it is believed that ignorance, myths and misconceptions about human body, sex and failure to adjust in marriage are the principle reasons for this. This course aims to help the youth in preparing physically, socially and emotionally for married life in a better way," Dr Bir Singh said.
Participants will also be advised on screening for certain genetic and acquired diseases before getting into nuptial alliance. Eminent specialists will take sessions in this exclusively designed participatory course.
"Our aim is to reach all people in the country. We want to introduce the course in all medical colleges that expert advice is available within their reach," he added.
Wednesday, August 6, 2008
Food Safety and Standards Act: Eateries to count your calories
August 6, 2008
By Syed Akbar
Our Special Correspondent
Hyderabad, Aug 5: Now, people will have the chance to control their daily calorie intake.
Pizzas, samosas, idlis, utappas, dosas, burgers and other food items served by restaurants should invariably carry the calorie information, besides the nutrition content.
The Central government has finally woken up on the Food Safety and Standards Act that was passed two years ago.
It has now set up the long-awaited Food Safety and Standards Authority to oversee the implementation of the FSSA, 2006, which among other things makes mandatory labelling of general food items served by food joints.
If the Centre has its way, every food item delivered through parcel service or carry home should be hygienically packed and the box/sachet should contain details on proteins, carbohydrates and fats including the cholesterol percentage. This will make people to understand what type of food and in what quantity they are consuming, so that they can regulate their total calorie intake. However, the rule does not apply to food served inside hotels or restaurants.
Presently only packaged foods contain such details and no freshly-made food items like idlis, pizzas, dosas and vadas provide nutritional information. Once the Act is fully implemented, every food item people order from restaurants or food joints will come in with full of nutritional facts and whether the food contains any genetically
modified ingredients. Every item should carry a label containing all these details.
The United States has already implemented such legislation to ensure that Americans do not consume more than the recommended 2000 calories a day. For Indians the recommended daily calorie intake is a little higher ranging between 2200 to 2400.
The idea behind the exercise is to "lay down science-based standards for articles of food and to regulate their manufacture, storage, distribution, sale and import, to ensure availability of safe and wholesome food for human consumption," says the Central legislation. It also regulates the manufacture, distribution, sale or import of any novel food, genetically modified articles of food, irradiated food, organic foods, foods for special dietary uses, functional foods, neutraceuticals, health supplements and proprietary foods.
Hoteliers, however, fear that they may not be able to implement the Rule since different customers have different food choices. "For big hotels it is OK. But for small hotels and restaurants hiring a nutritionist and analysing the contents in the food items is quite a Herculean task. For may it is practically impossible," said Jagdish Rao of Taj Mahal Group of Hotels.
But the Food Authority has planned to go ahead with the move by engaging a multi-skilled consultancy agency of for preparation of a blue print and assistance in structuring and operationalising the new regulations. The over all content of minerals or vitamins or proteins or metals or their compounds or amino acids should not exceed the recommended daily allowance for Indians). In case of enzymes they should be within the permissible limits.
Monday, August 4, 2008
Automated Underwater Vehicle: Maya to unravel secrets of Seas
August 4, 2008
By Syed Akbar
India's latest autonomous underwater vehicle, Maya, is all set to unravel the secrets hidden beneath the Deep and in the murky depths of rivers, lakes and natural tanks. Developed by the Goa-based National Institute of Oceanography, Maya, has been successfully tested for oceanographic studies, marine biology, water quality studies in fresh water reservoirs and dams and environmental monitoring of coastal waters and estuaries.
The country's first indigenously built autonomous underwater vehicle is now all set for large-scale commercial production. Scientists at NIO have utilised Maya for various studies and after successful results, they decided to transfer the technology to entrepreneurs.
Maya is a simple-looking yet sophisticated robot that's capable of passing on the secrets hidden in the unfathomable depths of oceans and seas. World-wide there are only 58 AUVs and NIO's successful testing of Maya has pushed India in the select league of nations with advanced technology in ocean sciences and technology.
According to senior scientist Desa Elgar, Maya is essentially made up of three parts. The first part is the free flooding nose cone of the vehicle, which houses the scientific sensors. This nose cone is swappable and is application specific. The second part is the sealed aluminium hull called the Core Pressure Unit, which contains the batteries, electronics, vehicle sensors, actuators, communication
systems and the electronics. The third part is called the tail cone and is
used to house the propulsion device.
Maya is rated for 200 mts depth operations and is capable of diving to different programmed depths and maintaining control of motion at those depths. It can follow mission paths that are pre-programmed.
Safety features enable the vehicle to return to the surface in case of hardware failure. The missions for the vehicle are loaded through a radio frequency link.
The AUV was used in different environmental settings including the Idukki reservoir in Kerala and a coastal station in the Arabian sea.
"Our experience in this project has confirmed the potential of small AUVs to work in confined spaces and in the open ocean, and as we have experienced, to discover unexpected processes in the ocean," said Elgar Desa. The vehicle was developed by R Madhan, P Maurya, G Navelkar, A Mascarenhas, S Prabhudesai, S Afzulpurkar and S
Bandodkar, besides Desa.
What are AUVs?
Autonomous Underwater Vehicles are essentially propelled robot platforms with on-board computers, power packs and vehicle payloads that enable automatic control, navigation and guidance of the vehicle.
They are used to acquire data from onboard sensors to sense physical, biological and
chemical properties in the ocean, in lakes, in estuaries, rivers, and dams. AUVs are novel to the extent that they can be programmed to dive and to maintain control at any given depth layer in a water body, to navigate by changing course at a chosen depth, to follow seabed terrain, and when a mission is accomplished to return ‘home’.
"A number of oceanographic problems need data acquisition without disturbing the environment. Shipboard profiling and towed instruments packages and samplers in such cases disturb the layer and can introduce errors in measurements. There are situations and places where divers are at risk and in these cases AUVs and Remotely Operated Vehicles equipped withappropriate sensors, power packs, and propulsion capability are able to address these problems to a large extent," the NIO team said.
In the case of Maya, NIO scientists have fitted Maya with sensors for oxygen, chlorophyll, conductivity, turbidity, temperature and depth.
The vehicle was programmed to dive to different depths in a staircase pattern up to 21 mts, and in the second mission at 1 mt depth up to 4 kilometres of continuous operation. It successfully collected data in the missions.
A single underwater motor is used to propel Maya. Two stern planes and a single rudder control diving and heading manoeuvre respectively.
The nose section on Maya is removable and different sensors can be fitted onto it for specific mission at sea.
Maya is designed to receive commands from shore and also send data over high-speed radio link. Underwater navigation uses the Doppler Velocity Log and a dead reckoning algorithm that estimates position below surface. Surface navigation is based on global positioning system.
"Maya has many applications in oceanography. It can collect standard oceanographic data in confined areas, carry out shallow water bathymetry using acoustic methods, detect blooms with the help of optical radiometers, and also work as a test platform for new sensor technologies," the NIO scientists said.
Sunday, August 3, 2008
Andhra Pradesh declares war against obesity
August 3, 2008
By Syed Akbar
Hyderabad, Aug 2: The State government is now on a novel mission: To discourage people from overeating.
The Civil Supplies Department has been entrusted with the task of taking up a massive campaign all over the State to discourage people from eating more than what's required to keep the body hale and healthy.
A five-member committee on nutrition set up by the State government has recommended that people should get adequate nutrition. While the malnourished will be asked to eat more, the well-to-do will be told to eat less. The State government has decided to earmark a part of its annual budget for the awareness campaign. It has also sought the help of the National Institute of Nutrition for the programme.
"Irregular diets are leading to overweight problems such as obesity. Obesity in our state and country today is still below 10 per cent and within manageable limits. Any laxity and business as usual approach today is a sure recipe for future nutritional disaster as is faced in western societies, especially in USA," Civil Supplies Commissioner Poonam Malakondaiah said in a circular issued by her.
The department also proposes to set up a special wing to counter overeating and its related problem of obesity and overweight. Though there are no government statistics on the number of obese people in the State, nutritionists and paediatrician point out that the problem is fast afflicting children. According to medical records, the problem is expected to increase to 60 per cent in the next 10 years in Andhra
Pradesh.
Andhra Pradesh ranks fifth in the country in terms of obese population. According to senior surgeon Dr TN Rao, obesity is fast assuming an epidemic proportion leading to a number of health problems including cardiac arrest and brain stroke.
The Committee recommended that government should earmark certain funds every year under the state budget to generate awareness on the need of balanced nutritional diet for the benefit of moderately and severely undernourished sections of population. Appropriate messages in local language with pictures may be disseminated through the vast network of PDS shops.
Friday, August 1, 2008
Eclipses will vanish one day
August 1, 2008
By Syed Akbar
Hyderabad, July 31: Eclipses will come to an end and so will be the superstitions associated with them. Astrophysicists predict that there will be no eclipses of the sun or the moon 500 millions years from now.
And the reason? According to them, since the moon is drifting away from the earth gradually, a day will come it will go away so far from the earth that it will not be able to hinder the light of the sun.
The moon is moving away from the earth by 1.6 inches or four centimetres every year. If this phenomenon continues for another 500 million years, there will be no eclipses.
The argument put forth by space scientists is that the moon was actually much closer to the earth about a billion years ago than it is now. Then the earth had just 18 hours a day unlike the present 24-hour day. If the moon moves away further, then the earthly day will be say 28 or 30 hours.
There will be no eclipses when the average earth-moon distance increases by 4.6 per cent, which is about 17,000 kilometres. At the present pace (i.e. 1.6 inches a year), the moon needs 500 million years to go so far away from the earth so as not to cause eclipses.
Scientists also predict that the moon will not go on moving away from the earth for ever. After 15 billion years from present, it will stop drifting away.
Then the moon will be about 1.6 times farther from the earth than it is now. But, scientists also say that neither the earth nor the moon will survive that long. Because by then the Sun will become a red giant star and the human planet along with its natural satellite will vanish space literally!
Eclipses solve scientific puzzles
August 1, 2008
By Syed Akbar
Hyderabad, July 31: Eclipses may have inspired awe in God or thrown people into superstitions, but they are natural events most looked forward to by scientists.
Eclipses have always helped scientists to study Mother Nature including its eautiful Earth and awe-inspiring skies, besides serving as natural tools to solve many a scientific puzzle that have racked the human brain for centuries.
Astrophysicists have utilised eclipses to make astronomical calculations or to discover new elements. They have also studied the rays of the sun and the spectrometre.
The eclipse that occurred on August 16, 1868 helped Sir Joseph Lockyer and Monsieur Pierre Janssen to independently discover helium gas in the corona of the Sun. elium, incidentally, is the first chemical element to be discovered outside the Earth.
Albert Einstein is famous for his theory of relativity. And the total solar eclipse of May 29, 1919 helped scientists prove that Einstein was right. Scientists showed that gravity can bend light.
"Eclipses help us in many ways. Scientists stand to benefit the most as eclipses provide an opportunity for them to photograph and study the composition of the Sun's corona. Eclipse come handy to calculate the exact dimensions of the Sun," Osmania University Professor of astronomy Dr G Yellaiah told this correspondent.
On February 16, 1980 during the solar eclipse scientists have observed the variations in temperature on earth through radio study. They also studied the corona of the Sun. It provides an wonderful opportunity to study the elements on the father of the solar system.
NASA scientists specialising in ultra violet imaging plan to examine changes in the upper atmosphere by modelling the changes in airglow seen during the eclipse. Airglow is just that, an effect caused by solar ultraviolet light striking the atmosphere.
By observing how the glow is extinguished then ignited as the Moon's shadow moves across the globe, astrophysicists hope that they will be able to estimate oxygen densities at different altitudes in the upper atmosphere.
Eclipses through history : The myth and the reality
August 1, 2008
By Syed Akbar
Hyderabad, July 31: Eclipses, both solar and lunar, have always fascinated man. Eclipses have been associated with major events, good and bad, throughout the human history.
The earliest known eclipse recorded dates back to 4000 years. It was Chinese
astronomers who recorded the event that occurred on October 22, 2134 BC. The second ancient eclipse recorded in human civilisation was in Mesopoamia (present day Iraq). It occurred on May 3, 1375 BC.
Several attempts have been made to establish the exact date of the epic Mahabharata war. Prof R Narayana Iyengar of the Indian Institute of Science, Bengaluru, has based his study of Mahabharata on eclipses and planetary positions that were referred into the epic. According to him, Mahabharata occurred between 1493 and 1443 BC.
"The 23-day Kurukshetra war between the Kauravas and Pandavas must have taken place in 1478 BC. This result may have an error band of one year, since the intervals between the three constraining eclipses are uncertain to the extent of one year," Prof Narayana Iyengar said.
According to historical records, Emperor Louis, head of the Frankish Empire of Western Europe, is said to have been so awe-struck by the total solar eclipse of May 5, 840 CE that he died shortly afterwards.
The Odyssey refers to a solar eclipse near Ithaca, which would correspond to 1178 BC. There is a reference to an eclipse in the Bible which could correspond to 15 June 736 BC.
On May 29, 1453 CE a rising full moon was eclipsed over Constantinople, then under siege by the Turk army. It is reported that this created such a dip in morale that in a few days Constantinople was defeated, leading to the end of the Roman Empire after 1130 years.
The expedition by Columbus was also linked to the eclipse of February 29, 1504.
More recently the eclipse (last of 20th century) of August 11, 1999 was linked to the fear of the new millennium. Several astrologers predicted catastrophes. But scientists brushed it aside saying technically the eclipse of 1999 was not the last of the last millennium. The Third Millennium technically started on January 1, 2001, as the ancients did not use the year zero.
However, the 1999 eclipse was the last of total solar eclipses of the last millennium. Though there were four solar eclipses in 2000 they were not complete, but partial.
Other notable eclipses in the history are: May 28, 585 BC that brought to an end the war between the Medes and the Lydians. The eclipse of April 10, 628 CE was attributed to the death of Japanese Emperor Suiko while that of May 1, 664 CE was linked to the death of the King of Kent Earcenbryht.
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