15 Dec 2012

What to avoid after a full meal

An irresistible spread: But heavy meals could affect one's health adversely in the long run
              An irresistible spread: But heavy meals could affect one's health adversely in the long run
         There are several activities that are a no-no after a heavy meal. Here are some of them…
You have eaten really well. The cook hired for the wedding reception is well-known — for his pathir peni, fresh jelebi, mixed rice varieties, sweet pachadis and vadai. And the hand-cranked icecream, how can you resist it?
Burp… Soak in the glow of satisfaction. This is how that XL-sized rock python on Animal Planet feels with an unsuspecting deer inside him. What next? A round of card games? Some coffee, tea? Test drive friend's swanky BMW? Crash to sleep the meal off? Or go adventurous, boot up the music, shake a leg!
Take care, warns nutritionist Vijaya Parameswaran. “After a full meal, your body will channel maximum blood circulation to your gastro-intestinal tract, to facilitate digestion. Vigorous/Intense exercising at this time may cause your cardiovascular system (heart) to be starved of optimum blood circulation.” Translated, it means “Psy fans, curb your enthusiasm for Gangnam Style after a full meal. Not good for the heart.” And don't slide into a nap after a heavy meal, Vijaya says. “Blood sugar surges after a meal and the focus for the next few hours is to normalise it. A nap after meals increases insulin dependence to normalise blood sugar, and may precipitate insulin resistance.” High BS also means a big no to desserts and high-sugar beverages post a full meal, since these make it harder to normalise blood sugars.
People who have suffered the post-meal syndrome add to the list of don'ts. Don't drink cold water after diving into a wedding spread, they say. It freezes food fat which then builds up in the intestine, narrows the digestive ducts and leads to obesity. Eating fruits after rich food is a bad idea too. A second helping of fruit salad? Brace yourself for a bout of abdominal bloating, diarrhoea, constipation or excess stomach acid. Tea is on the “never-after-a-heavy-meal” list. Its tannic acid forms a sediment by combining with proteins, and affects absorption of both protein and iron. Smoking after a meal makes it ten times more dangerous. If you chose to wear a belt to that reception, make sure you don't slacken it now. Comfortable, yes, but it can lead to decreased pressure in the abdominal cavity, and weakened digestion.
Elders in the family have warned us against bathing after a meal — full or less. You'll get dyspepsia, they said. And there's a surprising new rule: wait for 30 minutes before cleaning your teeth after a meal. Fruits, (particularly orange or lemon juice), vinegar, sport drinks and soft drinks have a very high level of acidity and can soften the enamel of your teeth. Brushing your teeth can damage the softened enamel. Wait till saliva neutralises the acidity.
How much of the amateur advice is trustworthy? In his News Today column, cardiologist and lifestyle advisor Dr. Philip Chua clears the myths about post-meal activity. Smoking is bad, he agrees, since the absorption rate following a meal is heightened, magnifying the ill effects of tobacco (nicotine) on our system. Avoid fruits only if you have intolerance, or you're on a diabetic diet. Eat fruits, they improve digestion. Question is, can you?
Tea is high in tannic acid, but it acts like a tonic — invigorates the brain, speeds up circulation, makes digestion easier. Go for a light, sugar-free cup. And yes, do not loosen the belt. A tight belt makes you conscious you are full and helps you fight the temptation to overeat. Don't believe in the mumbo jumbo about twisted intestines. Tradition that doesn't allow us to bathe after a meal has some truth in it, he says. Taking a bath (especially a warm one) does divert blood from the stomach to the skin, but doesn't impair digestion significantly. The general rule is: after a meal, don't indulge in strenuous activities that will move energy away from the stomach, which needs “enough” blood for digestion.
And don't sleep immediately after a meal. In some people, it causes irregular heartbeat. Habitually sleeping immediately after a meal supports the tendency to gain weight. “Don't eat again for four hours or longer, it makes the stomach grow larger” is sage advice. Eating heavily and frequently distends the stomach and conditions the brain to crave for more food. This is the inevitable path to obesity and its dangerous consequences.



Mobile touch screen
How do mobile touch screens work?
Sultanpur, Uttar Pradesh
Mobile phones may use two types of input devices. In regular mobile phones, a keypad type of device is used, which is mounted separately from the screen of the cellphone. Whereas in touch screen cellphones, a touch screen is a cellphone display screen that also acts as an input device. The touch screens are sensitive to pressure; a user interacts with the mobile applications by touching pictures or words on the screen.
Most mobile phone keyboards are basic in that they use a tactile surface you are accustomed to touching, and underneath is a basic rubber peg (black dot) which travels some depth until it encounters resistance in the form of the actual keyboard surface which is sometimes called a ‘bubble board.’
This is basically a semi-circle of aluminium shaped in the form of a dome and provides that springing effect of key and feedback on your finger when you press down and the button regains its at-rest shape and normal position.
Touch screen technologies used in mobile phones include resistive, capacitive and surface-wave based system.
The resistive system consists of a normal glass panel that is covered with conductive and resistive metallic layers. These two layers are held apart by spacers, and a scratch resistant layer is placed on top of the whole setup. An electrical current runs through the two layers while the monitor is operational.
When a user touches the screen, the two layers make contact exactly at that spot. The change in the electrical field is noted and the coordinates of the point of contact are calculated by the processor. Once the coordinates are known, a special driver translates the touch into something that the operating system can understand, much as a computer mouse driver translates the movements of a mouse into a click or a drag.
The change in the electrical current is registered as a touch event and sent to the controller for processing.
In the capacitive system, a layer of an electroconductive material (most often indium tin-oxide) that stores electrical charge is placed on the glass panel of the monitor. When a user touches the monitor with his finger, some of the charge is transferred to the user, so the charge on the capacitive layer decreases. This decrease is measured in circuits located at each corner of the monitor.
The computer calculates, from the relative differences in charge at each corner, exactly where the touch event took place and then relays that information to the touch screen driver software. Resistive touch screen panels are generally more affordable but offer only 75 per cent clarity and the layer can be damaged by sharp objects.
One advantage of the capacitive system over the resistive system is that it transmits almost 92 per cent of the light emitted from the monitor, whereas the resistive system transmits only about 75 per cent. This gives the capacitive system a much clearer picture than the resistive system. Also, the capacitive system has a very long life (about 225 million clicks).

NASA releases map of India on Diwali night

  • A satellite imagery of India on Diwali night released by NASA. Photo: PTI
               PTI A satellite imagery of India on Diwali night released by NASA. Photo: PTI 
  • NASA releases map of India on Diwali night. PTI graphic
                           PTI NASA releases map of India on Diwali night. PTI graphic
NASA, the national space agency of the U.S., on Thursday released a black and white satellite imagery of India Diwali night 2012, cautioning people against the fake image in circulation on the social media.
“On November 12, 2012, the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite captured this night-time view of southern Asia,” NASA said releasing a picture of India on this Diwali night.
“The image is based on data collected by the VIIRS ‘day- night band’, which detects light in a range of wavelengths from green to near-infrared. The image has been brightened to make the city lights easier to distinguish,” it said.
NASA said most of the bright areas in the imagery released by it are cities and towns in India. “India is home to more than 1.2 billion people and has 30 cities with populations over 1 million,” it said.
Cities in Bangladesh, Nepal, and Pakistan are also visible near the edges of the image.
“An image that claims to show the region lit for Diwali has been circulating on social media websites and the Internet in recent years. In fact, it does not show what it claims.
That image, based on data from the Operational Linescan System flown on US Defense Meteorological Satellite Program (DMSP) satellites, is a colour—composite created in 2003 by NOAA scientist Chris Elvidge to highlight population growth over time,” NASA said.
“In that image, white areas show city lights that were visible prior to 1992, while blue, green, and red shades indicate city lights that became visible in 1992, 1998, and 2003 respectively,” it said.
“In reality, any extra light produced during Diwali is so subtle that it is likely imperceptible when observed from space,” NASA said.

6 Dec 2012

Groundwater is gold

Since no more water is likely to be pumped from the Cauvery with the completion of the Phase IV Stage 2, it is groundwater that most of the development must depend on. 
Since no more water is likely to be pumped from the Cauvery with the completion of the Phase IV Stage 2, it is groundwater that most of the development must depend on.
       No individual borewell should be permitted to be drilled and only common use of groundwater under metered and tariff conditions should be encouraged in layouts, says water activist S. Vishwanath
The peripheral areas of cities are seeing an unprecedented growth. Land use is changing from agricultural to non-agriculture use and sites are being developed in ‘layouts’ all across. While infrastructure like roads and electricity can and will eventually reach the layouts, water supply is more difficult.
The Bangalore Metropolitan Regional Development Authority, assisted by 11 Local Planning Authorities, is the planning approval authority for over 8,000 sq. km. of area around the city of Bangalore.
Since no more water is likely to be pumped from the Cauvery with the completion of the Phase IV Stage 2, it is groundwater that most of the development must depend on. Groundwater is, however, getting increasingly overused in the surrounding semi-arid areas of the city.
How can the authority make sure that the people who move into these developments have water in the future? One good way to begin is to get the developer do a yield test for the borewells on site. If this is done in summer it is likely to give a better understanding of reliable yield for the entire layout. A quality test of the borewell water would also establish potability or otherwise.
This should be basic information with the authority as well as what potential buyers of sites or buildings should demand from the developer. No individual borewell should be permitted to be drilled and only common use of groundwater under metered and tariff conditions should be encouraged in layouts.

Implementation & design

While rainwater harvesting is insisted upon by the local planning authorities, a more detailed implementation and design would help both the authority and the consumer. It should be made conditional that all storm-water falling on non-private plot area is completely recharged into the ground. The recharge structures should be site specific and should be based on infiltration and recharge data from each site. Only in case where recharge is not possible should storage and reuse be permitted. In any case, each layout should be designed as a zero run-off area for rainwater.
All conditions imposed should be easily implementable, should bring tangible benefits to the occupiers, should be easy to monitor and should have clear ownership so that they are maintained in the long run and therefore sustainable.
At the macro-level, the BMRDA would be better off generating a detailed micro-watershed map of the area under its jurisdiction. It should then be able to push for the maintenance of these tanks and other water bodies plus their inter-connectedness through adequate policy, legislative and fiscal incentives.
The BMRDA should also map the aquifers, and detailed sub-aquifer maps overlapping with the micro-watershed maps should be generated so that the groundwater situation is better understood and managed with the development that will take place inevitably in the megalopolis area. The Karnataka State Pollution Control Board insists on a sewage treatment plant for each development in the BMRDA zone. While this is motivated with a need to prevent water pollution and to add to reuse and recycling of water, the practical aspects of what happens to these treatment plants and who maintains them should be studied.
Resident Welfare Associations and flat owner associations find it difficult to maintain these units. As units or houses are built incrementally, it is difficult for the treatment plants to become fully functional until occupancy is at least 50 per cent and above.
As a matter of choice individual on-plot sanitation systems like septic tanks and baffled reactors with the right design should be permitted. These have the benefits of being maintained by individual owners and also they demand much less water than piped sewerage. A dual system of grey-water disposal and black-water disposal on plot should be permitted.
While on-plot sanitation systems can be maintained with as low as 70 lpcd of water, piped sewerage will demand at least 135 litres per person per day especially for self-cleansing velocity requirements.
The sustainable management of water and sanitation outside the BWSSB influence zone is a challenge. The BMRDA has to think wisely and move ahead quickly so as to avert a serious water shortfall situation.
This would be water wisdom for a city.

Jupiter to make closest approach to Earth

A montage of images of Jupiter and its volcanic moon Io. File photo.
                         AP A montage of images of Jupiter and its volcanic moon Io. File photo.
          Jupiter, the largest after the Sun in the solar system, will be at its biggest and brightest on Monday night much to the delight of sky-gazers.
The planet, which has a system of rings, is at its closest approach and thus would appear more big and bright than usual, N. Sri Raghunandan Kumar of Planetary Society of India said.
The planet can be seen with naked eyes an hour after the sunset in the eastern direction on Monday. It will be visible all through the night and at midnight one can spot it in the southern direction at a higher elevation, he said.
According to him, Jupiter, which has a large number of natural satellites, will be in ‘opposition’ on Monday night. “A planet is said to be in opposition when it is directly opposite to the Sun from our view from Earth,” he said.
At its opposition, the planet is fully illuminated by the Sun and appears disc-like, he said, adding, Jupiter’s opposition occurs every 13 months.
The last opposition of the planet occurred on October, 29, 2011 and the next will be January 6, 2014.
The minimum distance of Jupiter from Earth is approximately 588 million kms while its maximum distance is about 967 million kms.
On Monday, the ring planet will be at 608 million kms, which is very close to its minimum distance from Earth.
“Because of its closeness to Earth, Jupiter will be shinning very bright at -2.8 Magnitude,” Mr. Kumar said.

Fly high

Venkata Srinath and the UAV 
                                                           Venkata Srinath and the UAV
              Geeta Padmanabhan is awe-struck by Chennai engineer Venkata Srinath’s creation — portable micro / mini Unmanned Aerial Vehicle, and look up for more information
On a calm afternoon, I stood in a field off the Chennai-Bengaluru Road in Sriperumbudur. A few feet away, Venkata Srinath, ECE engineer from College of Engineering, Guindy, was setting up what looked like a tripod. He clamped a control panel to its belly and began to assemble a small plane. “Some of its components have been imported, there is system integration,” he said straightening up. “Remember the tragic project in Three 3 Idiots? My inspiration.”
He was ready. “This is a single-man portable micro / mini UAV (Unmanned Aerial Vehicle) launched as vertical take-off or by hand,” he said, letting go of the vehicle. We held our breath as Garuda-02 soared into the sky and settled in its orbit above the field. Mission accomplished! “Note that there’s no runway,” said Srinath. “It lands on grass, sand, pebbles — any hard surface without damage.” The UAV has embedded control equipment monitored by a Ground Control System (GCS). Its fully-charged battery (12.5V) helps it keep an eye on altitude, radius etc. I peep at the GCS.
Garuda-02 flew 200 mt above but could reach 1,000 mt around a five-km radius. It has a 30-minute run. Because of its small wing span (100 cm), it might go out of view, but does not matter. Srinath pressed the auto-return button (I hissed “come back!”), it came into view and landed neatly at the take-off point. Before packing up, Srinath removed a chip, inserted it in his laptop and clicked it open. So that’s what the “toy” was all about — Garuda’s hi-def camera had been taking pictures every two seconds while circling the area!
Imagine what an “eye-in-the-sky” means. Lab-electronics (where Srinath develops UAVs) lists 50 civilian / military apps, including fire-assessment, wildlife movement and disaster control.
Srinath’s planning a high-end Garuda-04. “It will fly in a fixed route and transmit video from a daylight or night camera, controlled through a ground PC,” he said. Gimbal mounting of cameras and digitally-stabilised videos will ensure clear pictures. Garuda-04 will track and lock a target, carry additional sensors to detect radiation and pollution in the atmosphere.
Eye-in-the-sky UAVs aren’t new to Indian skies. Daksha, a UAV developed by Madras Institute of Technology was roped in to survey granite blocks and quarries spread over hundreds of acres in Madurai district. It is reported to have sent video footage of nooks and crannies not accessible to manual surveillance. Befitting a modern thriller, its live footage reportedly showed a secret room hidden among granite blocks.
Netra, built jointly by IIT graduate Ashish Bhat, friends (IdeaForge) and DRDO, is claimed to be the world’s lightest and smallest UAV in its category. Weighing 1.5 kg, it can fly up to 1.5-km line of sight, can hover, spot a person 400 mt away, and send real-time images from 200 m above. The vehicle is compatible with thermal-imaging cameras for night-time use, can survey all terrains, including jungles, plains, mountains and deserts. Its rechargeable batteries give it a flight time of 30 minutes and a top-speed of 25 km an hour. The UAV’s auto-pilot controller receives inputs from GPS, magnetometers, gyroscopes, accelerometers and altitude sensors, which provide stability to the vehicle and help it navigate. Our armed forces are thrilled about its use in anti-terror and counter-insurgency operations, hostage situations, border infiltration, law enforcement, search-and-rescue, disaster/crowd management. It proved its worth, covering a Chandigarh rally. It is Netra you got to see in 3 Three Idiots.
A quiet revolution
Is flying UAVs permitted? BBC’s Newsnight discussed it. Calling it a “quiet revolution”, it said civilian UAV projects are on for border security, police surveillance and even transporting goods. All this raises serious safety and privacy questions. The US airspace regulator (FAA) expects 10,000 unmanned commercial aircraft to fill American skies by 2017, a plan that has faced fierce criticism. Campaigns are underway to make a number of US cities “drone free” and politicians want drone operators to inform the government of any data collected.
UAV development, however, seems unstoppable. A key piece of technology currently missing in civilian drones is a “detect-and-avoid” system that will automatically steer the pilotless craft from commercial airliners and crash-land in a safe area, if needed. “Whoever cracks it first will have a winner on their hands,” BBC said.
(For details, visit www.labelectronics.com)
When airborne, UAV’s wings fly point-to-point using the same GPS technology found in most smartphones
Multinational freight firms want unmanned aircraft to deliver mail and cargo
Small wing-shaped drones are being used to photograph and analyse agricultural land, to pinpoint where extra fertilizer / pesticide is needed
Police forces have tested small, lightweight drones as air support units
It is legal to fly your drone in the U.K. without special permission if it weighs less than 20 kg and is flying more than 150 m from a congested area

Climate change serious for India, says expert

Greenpeace activists demonstrate in front of Gateway of India, in the Arabian Sea, to highlight the threat to Mumbai from rising sea levels. Photo: Vivek Bendre 
                               The Hindu Greenpeace activists demonstrate in front of Gateway of 
                               India, in the Arabian Sea, to highlight the threat to Mumbai from rising 
                               sea levels. Photo: Vivek Bendre
             Terming the current global climate change scenario as “serious times”, a US environmental law expert on Wednesday cautioned that the rise in sea level in the Indian Ocean could make cities like Kolkata and Mumbai vulnerable.
“There might be particular problems due to the sea level rise in the Indian Ocean. Cities like Kolkata and Mumbai are the vulnerable cities,” said Rob Verchick, who holds the Gauthier-St. Martin Chair in Environmental Law at Loyola University, New Orleans, US. He is also the faculty director of the Centre for Environmental Law and Land Use at the university.
Mr Verchick added, “Surat and Ahmedabad are responding well to adapt to the climate change. Surat has a climate change board and they are monitoring the situation quite well.”
He was addressing students at the School of Oceanography and Environmental Studies, Jadavpur University, here
Mr Verchick, who recently served US President Barack Obama’s administration as deputy associate administrator for policy at the Environmental Protection Agency, said, “For adapting to climate change we have to adopt smarter ways. The first thing we must do is that government and other agencies should look in to assess vulnerability of a place to climate change like temperature, sea level rise etc.”
“Then we have to ask, how will those changes affect the area and then in a democratic process decide what we can do with the area,” he said.

Hottest planet cold enough for ice

Proved right: A 68-mile-diameter crater in the north polar region of Mercury has been shown to harbour water ice. 
                               AP Proved right: A 68-mile-diameter crater in the north polar
                               region of Mercury  has been shown to harbour water ice.
            Mercury, the innermost planet in the Solar System, is like a small rock orbiting the Sun, continuously assaulted by the star’s heat and radiation. It would have to be the last place to look for water.
However, observations of NASA’s MESSENGER spacecraft indicate that Mercury seems to harbour enough water-ice to fill 20 billion Olympic skating rinks.
On November 29, during a televised press conference, NASA announced that data recorded since March 2011 by MESSENGER’s onboard instruments hinted that large quantities of water ice were stowed in the shadows of craters around the planet's North Pole.
Unlike Earth, Mercury’s rotation is not tilted about an axis. This means one side of the planet permanently faces the sun, becoming hot enough to melt lead. The other side, however, constantly faces away from the sun, and is extremely cold.
This characteristic allows the insides of craters to maintain low temperatures for millions of years, and capable of storing water-ice. But then, where is the water coming from?
Bright spots were identified by MESSENGER’s infrared laser fired from orbit into nine craters around the North Pole. The spots lined up perfectly with a thermal model of ultra-cold spots on the planet that would never be warmer than -170 degrees centigrade.
These icy spots are surrounded by darker terrain that receives a bit more sunlight and heat.
Measurements by the neutron spectrometer aboard MESSENGER suggest that this darker area is a layer of material about 10 cm thick that lies on top of more ice, insulating it.
Dr. David Paige, a planetary scientist at the University of California, Los Angeles, and lead author of one of three papers in Science that indicate the craters might contain ice, said, “The darker material around the bright spots may be made up of complex hydrocarbons expelled from comet or asteroid impacts.” Such compounds must not be mistaken as signs of life since they can be produced by simple chemical reactions as well.
The water-ice could also have been derived from crashing comets, the study by Paige and his team concludes.
Finding water on the system’s hottest planet changes the way scientists perceive the Solar System’s formation.
Indeed, in the mid-1990s, strong radar signals were fired from the US Arecibo radar dish in Puerto Rico, aimed at Mercury’s poles. Bright radar reflections were seen from crater-like regions, which were indicative of water-ice.
“However, other substances might also reflect radar in a similar manner, like sulphur or cold silicate materials,” says David J. Lawrence, a physicist from the Johns Hopkins University Applied Physics Laboratory and lead author of the neutron spectrometer study.
Lawrence and his team observed particles called neutrons bouncing and ricocheting off the planet via a spectrometer aboard MESSENGER. As high-energy cosmic rays from outer space bombarded into atoms on the planet, debris of particles, including neutrons, was the result.
However, hydrogen atoms in the path of neutrons can hold the speeding particles almost completely as both weigh about the same.
Since water molecules contain two hydrogen atoms each, areas that could contain water-ice will show a suppressed count of neutrons in the space above them.
Because scientists have been living with the idea of Mercury containing water for the last couple decades, the find by MESSENGER is not likely to be revolutionary. However, it bolsters an exciting idea. As Lawrence says, “I think this discovery reinforces the reality that water is able to find its way to many places in the Solar System, and this fact should be kept in mind when studying the system and its history.”

American scientist invents plastic light bulb

            A US scientist has invented a new kind of light bulb that uses plastic polymers and nano materials to generate light that is more energy-efficient than current fluorescent lights and is easier on the eye.
Details of the new invention were published Monday on the website of Wake Forest University in North Carolina, where the inventor, physics professor David Caroll, is based.
The new plastic lighting uses the same amount of electricity as LED bulbs and half as much as fluorescent bulbs. The device is made of three layers of white-emitting polymer blended with a small amount of nano-materials that glow when stimulated with electrical current to create bright, perfectly white light similar to the sunlight human eyes prefer. It can be made in any colour or shape — from flat sheets to replace office lighting to standard bulbs in household lamps.
“People often complain that fluorescent lights bother their eyes, and the hum from the fluorescent tubes irritates anyone sitting at a desk underneath them,” said Dr. Carroll.
Dr.Caroll is the director of the Centre for Nanotechnology and Molecular Materials. “The new lights we have created can cure both of those problems and more.”

24 Nov 2012

Play an eco friendly game

  • Join Gaurav, host of Disney Channel’s Art Attack.
    Join Gaurav, host of Disney Channel’s Art Attack. 
  • Step 1.
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Disney Channel's Art Attack host Gaurav teaches you how to make an eco-friendly game on Children's Day.
Join Gaurav, host of Disney Channel's Art Attack and make yourself an eco friendly indoor game. You can customize and make it in whatever theme you want —Pirates, jungle etc.
You will need
1. Caps of Old Plastic Bottles – to make your Game Pieces
2. One big Cardboard Piece
3. Art Attack paste (made with one part glue and one part water)
4. Cardboard tube of an Old toilet paper roll
5. Old newspapers
6. Markers and colours
7. Scissors
8. Tape
9. Art attack paste (equal amounts of glue and water)
Step 1
Take the piece of cardboard and draw any shape you want. I have drawn the shape as shown in the image. Make a path. With the help of an adult cut the cardboard in the shape drawn as shown in the image.
Step 2
Now make trees and grass. To make the trunk of the tree, take the cardboard tube of the toilet paper roll and stick it to the centre of the board, with the help of tape.
Step 3
To increase the width of the tree take some old newspaper, fold and make strips. Stick it on the cardboard roll. Make paper balls and stick it with the tape to the top of the cardboard roll. Stick it with cellotape.
Step 4
Take pieces of newspaper and stick it on the tree with art attack paste. Cover the whole tree. To make the grass take crumbled pieces of newspaper and stick it around the tree. On the area around it, where the game has to be played, stick sheets of paper. This area should be smooth as here is where the game pieces are kept.
Step 5
Now! to do some colouring. Use dark green for the tree and brown for the trunk. For the grass use light green. Do some shading to make it look more real. With a black marker, divide the path into small parts. Make eco symbols like water taps, light bulbs etc., inside each part. Colour the individual parts wtih any two colours . Colour the start point black and white. Make sure your whole board is coloured and the newspaper can't be seen.
Tune in to Disney Channel on Sunday's at 9:30 AM to catch more of this!
Step 6
Voila! Your eco friendly game is ready! You can punish the player who reached the open tap spot and give an extra turn to the player who reached the closed tap spot.

Hills, rich in flora and fauna

Green warrior: Fighting for the hills.
Green warrior: Fighting for the hills.
             Sneha is passionate about the environment. And as a crusader for the cause, she made a presentation on the hill ranges in Andhra Pradesh.
For T. Sneha, a student of Std. IX, Sudhaha Little Citizens High School, Tirupati, biodiversity is close to her heart. She participated in the XI Conference of Parties to the Conservation of Biological Diversity, conducted in Hyderabad, under the auspices of the National Biodiversity Authority of India. She helped prepare recommendations on “Aichi targets for biodiversity conservation”. Aichi targets are the 20 Points agreed upon by signatories to the Xth convention held at Nagoya, Japan, in 2010.
Sneha, a member of National Green Corps’ (NGC) Eco-club, participated in the sub-event “Young India for biodiversity”. She was the only representative from the Rayalaseema region. She presented an overview of the Seshachalam hill ranges spread over Chittoor and Kadapa districts, which are rich in biodiversity.
Be a friend
Her presentation lasted four minutes and she spoke about the rare endemic species of fauna like golden gecko (golden lizard), civet cat, Jerdon’s Courser, Yellow-browed bulbul, Indian fox, Malabar giant squirrel, Banded peacock (butterfly), slender loris (a cat-like nocturnal animal) and flora — Cycas beddomei and Red Sanders.
The presentation highlighted the need for humans to make a difference and protect the environment.
“After the meet, we students decided to document our ‘backyard biodiversity’ i.e., the plants, creepers, insects, worms, animals, streams we see in our neighbourhood, ” said Sneha.
Strongly believing that children can make a difference, Sneha urges her peers to motivate their parents to quit practices perceived to be eco-unfriendly. She says we can make a start by ensuring segregation of waste and curb practices that could lead to the extinction of birds and animals in our neighbourhood.
Seshachalam Biosphere Reserve
This is the first biosphere reserve in Andhra Pradesh. It was notified on September 20, 2010. The total area of the Ministry of Environment and Forests-designated reserve is 4756 sq.km, which include parts of Chittoor and Kadapa districts in the Deccan peninsula. The area is divided into three — the core zone (kept free of human activity), buffer zone (where activity will have to conform to MoEF guidelines) and transition zone (comprising settlements, croplands and managed forests). Interestingly, the Tirumala hills known to be the abode of lord Venkateswara, also falls in this Reserve.
The biosphere is expected to be a part of the UNESCO network. This would facilitate exchange of information and infusion of funds through the Man And Biosphere (MAB) programme.

Arctic ice could vanish within 10 years: Scientists

The entire region could be eventually free of ice if the estimates prove accurate. This would trigger a ‘gold rush’ for oil reserves and fish stocks in the region. File Photo: AP
AP The entire region could be eventually free of ice if the estimates prove accurate. This would trigger a ‘gold rush’ for oil reserves and fish stocks in the region. File Photo: AP
Arctic sea ice could vanish within 10 years as it is melting much faster than previously believed, thanks to global warming, warn scientists, claiming that the process is 50 percent faster than the current estimates.
New satellites being operated by the European Space Agency paint a grim picture of 900 cubic km of ice already having melted over the last year.
This is 50 percent higher than the current estimates from environmentalists, they claim. It is suggested that the increase is down to global warming and rising greenhouse gas emissions, the Daily Mail reports.
The entire region could be eventually free of ice if the estimates prove accurate. This would trigger a ‘gold rush’ for oil reserves and fish stocks in the region.
“Preliminary analysis of our data indicates that the rate of loss of sea ice volume in summer in the Arctic may be far larger than we had previously suspected,” said Seymour Laxon, of the Centre for Polar Observation and Modelling at University College London (UCL), where CryoSat-2 data is being analysed.
Scientists launched the CryoSat-2 probe in 2010 specifically to study ice thickness. Until then most studies had focused on the coverage of the ice. Submarines were also sent into the water to analyse the ice. The methods are said to have given a picture of changes in the ice around the North Pole since 2004.
Data from the exploration shows that in winter 2004, the volume of sea ice in the central Arctic was approximately 17,000 cubic km. This winter it was 14,000 km, according to CryoSat.
Chris Rapley, professor at UCL added: “Before CryoSat, we could see summer ice coverage was dropping markedly in the Arctic. But we only had glimpses of what was happening to ice thickness. Obviously if it was dropping as well, the loss of summer ice was even more significant.”

Greenhouse gases at record high in 2011: UN

In this Sept. 15, 2009 file photo, a deforested area is seen near Novo Progresso, in Brazil's northern state of Para. The Brazilian Amazon is arguably the world's biggest natural defence against global warming, acting as a “sink,” or absorber, of carbon dioxide.
AP In this Sept. 15, 2009 file photo, a deforested area is seen near Novo Progresso, in Brazil's northern state of Para. The Brazilian Amazon is arguably the world's biggest natural defence against global warming, acting as a “sink,” or absorber, of carbon dioxide.
                 The UN weather agency says concentrations of the main global warming pollutant in the world’s air reached a record high in 2011.
The World Meteorological Organization says the planet averaged 390 parts per million of heat-trapping carbon dioxide in the atmosphere, up 40 per cent from before the Industrial Age when levels were about 275 parts per million.
WMO officials said on Tuesday there was a 30 per cent increase in the warming effect on the global climate between 1990 and 2011, mainly due to carbon dioxide from fossil fuel burning.
WMO Secretary-General Michel Jarraud said the 350 billion metric tons of carbon dioxide added to the atmosphere since 1750 “will remain there for centuries, causing our planet to warm further and impacting on all aspects of life on earth.”

A biological battery


                Plugging into sources of energy within our body — such as heat, internal motion or metabolites — to power implanted medical devices has long been the goal of biomedical engineers. Now researchers based in Cambridge, Massachusetts have demonstrated that a sensing device embedded in the ear can be powered by the ear’s own electrochemical battery.
Our auditory mechanism picks up external sounds and sends information to the brain in the form of neural signals. When the sound wave hits the ear, the eardrum vibrates in response. This mechanical energy must to be converted into an appropriate electrochemical impulse.
Deep inside the ear, the cochlea perceives the frequency of the vibration. It maintains a gradient of potassium and sodium ions across a delicate membrane via a system of pumps and channels. This natural battery, which makes neurotransmission of sound possible, generates a net positive voltage.
Researchers have known about the existence of this endocochlear potential (EP) for decades, but had not devised ways of using this voltage without interfering with the mammal’s hearing, says Konstantina Stankovic, otologic surgeon at Massachusetts Eye and Ear Infirmary, medical lead of the collaborative team. “What we have is both a conceptual and technological breakthrough. New electrodes and new electronics had to be developed to make safe harvesting possible,” she says.
Prof. Anantha Chandrakasan’s group at Massachusetts Institute of Technology designed the chip to extract current from the ear, keeping in mind the many physiological constraints. In the prototype, the harnessed power drives a wireless sensor that can monitor the value of the EP. A radio transmitter relays data to the clinician who uses the numbers to gauge the ear’s condition.
Though our ear functions on EP ranging from 70-100 millivolts, this voltage is not enough for electronic implants. “Since the power from the source is so small, we accumulate energy on a capacitor. Once the capacitor fills up, it can drive a higher power electronic circuit,” says Chandrakasan. “We power a 2.4 Gigahertz radio in this case.”
But transistor-based electronics need hundreds of millivolts to start. A wireless receiver on the integrated circuit gets a short burst of radio waves to kick-start the system.
The setup, implanted in the ear of a guinea pig, could transmit data for five hours without compromising normal hearing. Design optimization and more testing lie ahead.
“Thus far, we have demonstrated feasibility of sensing the EP, powered by the EP,” says Stankovic. “But we are eager to couple this energy-harvesting chip to a variety of molecular and chemical sensors to sense the inner ear and its environment and identify the most promising biomarkers relevant for the ultimate human application.”
The device cannot power multichannel cochlear implants or hearing aids as yet. But Charley C. Della Santina, professor of Otolaryngology and biomedical engineering at Johns Hopkins University, who is unconnected to the research team, points out that there is a real need for a system that can monitor the EP in animal models of Meniere’s disease — an inner ear disorder that affects balance and hearing. And, this device, he says, may just fit the bill.
Plus, the data collected in vivo could transform our understanding of how the mammalian ear works, says Stankovic. The paper that describes the findings appears in the latest issue of Nature Biotechnology.

'Death throes of a star shows how Sun may die'

Death throes

               Astronomers have discovered a dying Sun-like star briefly coming back to life after casting its gassy shells out into space, mimicking the possible fate our own Solar System faces in a few billion years.
A new picture of the planetary nebula Abell 30, located 5500 light-years from Earth, is a composite of visible images from the NASA/ESA Hubble Space Telescope and X-ray data from ESA's XMM-Newton and NASA's Chandra space telescopes.
Planetary nebula is the name given to the often-concentric shells of stellar material cast into space by dying stars. To astronomers of the 18th century, these objects looked like the colourful "blob" of a planet.
Astronomers now know that as a star with less than eight times the mass of the Sun swells into a red giant towards the end of its life, its outer layers are expelled via pulsations and winds.
The stellar wind bombarding dense clumps of material provides a chilling look at the possible fate of Earth and its fellow planets in our own Solar System in a few billion years' time, ESA said in a statement.
When our Sun emits its final gasps of life at the heart of a planetary nebula, its strong stellar wind and harsh radiation will blast and evaporate any planets that may have
survived the red giant phase of stellar evolution.
Ultraviolet radiation shining out from the stripped-down hot stellar core then lights up the ejected shells, resulting in intricate artworks that can be seen by modern telescopes.
The star at the heart of Abell 30 experienced its first brush with death 12,500 years ago - as seen from Earth - when its outer shell was stripped off by a slow and dense stellar wind.

          Optical telescopes see the remnant of this evolutionary stage as a large, near-spherical shell of glowing material expanding out into space.
About 850 years ago, the star suddenly came back to life, coughing out knots of helium and carbon-rich material in a violent event.
The star's outer envelope briefly expanded during this born-again episode, but then very rapidly contracted again within 20 years.
This had the knock-on effect of accelerating the wind from he star to its present speed of 4000 kilometres per second -over 14 million kilometres per hour.
As this fast stellar wind catches up and interacts with the slower wind and clumps of previously ejected material, complex structures are formed, including the delicate
comet-like tails seen near the central star.

13 Nov 2012

‘Thataku tapakayalu’ are here again

G. V. R. Subba Rao
The crackers lost charm after the arrival of fancy items
The ‘Thataku tapakayalu’, one of the favourite crackers of coastal Andhrites for Diwali, are on sale again at fire cracker stalls here. Also on sale are other hot favourite ‘tara juvvalu’. Juvvalu, fondly called ‘havvai suvvai’, are not available abundantly at the stalls, but they made their presence felt.
Very few stalls at the PWD Grounds where the fire crackers are on sale, have put up the thataku tapakayalu, the bombs covered with palm leaves. A bunch of 25 thataku tapakalu is available for Rs.30. “There were no ‘Lakshmi’ bombs or ‘atom’ bombs, which one saw everywhere during Diwali during one’s childhood. The ‘thataku tapakalu’ were the only source to make a loud noise during the Diwali,” recalls Chaluvadi Satyanarayana, a senior citizen.
Thataku tapakayalu lost their charm after the advent of fancy items and crackers from Sivakasi. Generally, the youth used to make thataku tapakayalu and tara juvvalu at their homes. It was a must item in the list of crackers and even children used to insist on buying a pack for them, added S. Narasimha Rao, his associate, who was at the grounds to buy crackers for his grandchildren.
Some local traders also used to make the thataku tapakaylu. But, due to cost escalation, labour problems and flooding of fancy items, the manufacturing of this item has come down. Thataku tapakayalu, also called as galaxies, were not seen during last two-three years, says Jupudi Srinivas, a stall owner. There used to be competitions between colonies and localities in lighting up tara juvvalu. The juvvalu, a primitive form of ‘rocket crackers’ used to criss-cross between two contesting groups standing at the ends of a street. The havvai suvvai were considered as big man’s cracker, and children used to look at it with awe, recalls Mr. Satyanarayana.

Why do earthen pots lose their efficiency in keeping the water cool after being used for a few years?

            Fresh earthen pots have multitudinous and crisscross narrow channels running from inside to outside of their walls like in a sponge. Or, we say that the walls of fresh earthen pot are highly porous.
When water is held in such fresh earthen pot, part of the water bleeds out through these pores by capillarity and interfacial affinity and makes the outer surface of the pot rather wet.
However, the water from inside cannot gush out though these pores like a shower because of the crisscross nature and narrowness of the channels and the fineness of the pores.
Thus, the effective exposure area for water in a fresh earthen pot, is not only the top meniscus in the pot but also the wetness on the outer surface of the pot. When water evaporates from these surfaces, the molecules leaving the pot take along heat from the pot’s walls and the water in the pot becomes cooler.
Potable water is not pure water; it contains some minerals such as potassium, sodium, magnesium and calcium salts, suspended particles, dissolved oxygen and carbon dioxide, etc among others.
During the course of usage, some of these calcium and magnesium ions in water tend to precipitate as insoluble carbonates and sulphates which gradually plug the pores and channels of the pot walls.
The suspended particles, dust collected inside and outside the pot during usage and some algal and moss growths also block these pores and discourage the development of wetness of the outer walls of the pot.
In the event of decreased net area of exposure, the rate of evaporation and the scope for loss of internal heat is drastically reduced.
That is why earthen pots lose their efficiency in keeping the water cool after being used for a few years.
Department of Chemistry
National Institute of Technology Warangal
Warangal, Andhra Pradesh

Why do we feel relief when we gargle with salt in hot water when suffering from throat pain?

Neyveli, Tamil Nadu
           Soreness in the throat can cause throat pain. Soreness of throat is generally due to the infection of the bacterium called Streptococcus. So it is called strep throat. A strep throat is usually inflamed due to bacteria making widespread damage on our soft tissues or mucosa.
These inflammations (known as edemas) are usually filled with water. When we gargle with warm salt water that is saltier than our body fluids (hypertonic solution), through osmosis the salt draws out the edema fluid.
The principle behind it is that if a porous partition separates dilute and concentrated solutions then the dilute solution permeates through the porous partition into the concentrated solution.
This process does not stop till the concentration of both the solutions is equal. Salt water is more concentrated than the water in bacteria. The membrane of the cell of inflammatory tissue acts as a porous partition. So the salt draws water from the swollen cells that are causing pain and the inability to swallow foods.
Not only that, it will also draw water from the bacteria. When the bacteria gradually lose their body fluid they cannot remain active after dehydration. So they wither and die. This phenomenon is called plasmolysis.
The other benefits are; when the salt water enters the throat, the solution helps to neutralize acids in the throat, restoring the natural pH balance that had been disrupted by the sore throat.
By doing this, the burning sensations are relieved and the mucous membranes become less irritated, which can speed healing.
In addition to neutralizing acid, the salt water gargle helps to wash away unwanted mucus and increase the blood flow to the throat. The capillaries then become dilated, which allows for faster circulation of infection-fighting cells.
Instead of table-salt-dissolved water it is better to gargle with hypertonic saline water which contains two tea spoons of table salt and one tea spoon of baking soda (sodium bicarbonate, not baking powder) dissolved in 200 ml of purified water.
The sodium bicarbonate helps to improve the mucous-solvent properties of the irrigating solution.
The warm water and salt grains bathing in our throat may feel good. But too much salt can harm our mucosa. So moderate gargling is advised.
Moreover gargling with salt water does not actually help to heal the strep throat like a medicine would, but it does provide temporary relief. If we do not experience relief as a result of the salt water gargling and if the pain persists we must consult a doctor to get proper antibiotic treatment.

12 Nov 2012

Why is a choke required in a tube light and not in a CFL?

Choke’s role

Sultanpur, Uttar Pradesh
            Both conventional fluorescent lamps (usually 4 feet long) and compact fluorescent lamps — CFLs ( much smaller both in length and diameter of the tube) used in lighting applications are low pressure mercury vapour discharge lamps.
These lamps generate light by the process of fluorescence (accomplishing conversion of invisible ultra-violet, UV to visible light) by electrical discharge-passage of electricity through gaseous-vapour medium along the column of the tube.
When electrical discharge could strike the column of the tube, lot of invisible UV radiation having wavelength dominantly at 254 nm is generated. This UV radiation when strikes the white coating inside the tube made of fluorescent material- phosphors gets converted to visible light with wavelengths in the region of 400-700 nm through the process of fluorescence.
The electrical resistance of the discharge column of the tube increases with dimensions and decreases with miniaturization of lamp dimensions.
For a conventional fluorescent lamp, the ballast used is a choke which essentially a leak transformer (made of bulk coil windings) which momentarily produces an inductive kick in the form of high voltage (approximately 1000 volts) so that the electrical discharge could be struck along the column of the tube. So in a conventional fluorescent lamp the role of the choke is to initiate the electrical discharge process.
Once the discharge is struck it can be sustained through the drop in electrical resistance of the column. But CFLs, being smaller in dimensions offering much lower electrical resistance do not require such bulky chokes. Instead the discharge in CFLs is initiated by much compact electronic circuits integrated into the CFL holder. Usually these electronic ballasts are small oscillator circuits producing high frequencies (approximately 10 kilo Hertz) facilitating flicker free quick start of lamp as electrical discharge strikes faster at such high frequencies.
Luminescence Group
Karaikudi, Tamil Nadu

4 Nov 2012

Spot your train with ease

T. Ramachandran

RailRadar helps passengers know location of 9,700 trains
Train-tracking has become easier than ever before with all trains, except those running on the Mumbai suburban network, being covered live by the web-based trainenquiry.com service of the Indian Railways. It has now taken on a new map-based dimension with the addition of railradar.trainenquiry.com.
At any point in time, information can be had online or via SMS about the location and schedule of the 9,700-odd trains that run a given week. And what is more fascinating is that the location of any train, except those in the Konkan railway belt, can now be seen on a map anytime — represented by a colour-coded arrow that indicates whether a train is running on time or late.
Though the enquiry service has been working for some years and providing information on select trains, it has become comprehensive in its new avatar launched last April. A mobile version was released in May; and just a few weeks ago came the map-based RailRadar add-on.
The site had witnessed no less than a crore visitors in the few months it was launched. And every day, on an average, more than 3.5 lakh users flocked to the trainenquiry.com and RailRadar websites, 20 per cent of whom used mobile devices to get information, said Manish Rathi, co-founder of Railyatri, which is involved in the operation of the site set up by the Centre For Railway Information Systems.
The appeal of the trainenquiry.com service lies in the ease of use. By entering some details in a search box — a train’s name or number or the names of stations — the user is presented with a list that can be narrowed down to a specific option.
By clicking on the train name displayed, the user can know where it is — whether it has halted at a station or is approaching one, the timings, the other stations en-route, the distances, and so on. Also the stations it has passed through and when, and the distance already traversed. It also tells us whether a train is running on schedule or is late at a point in time. (For getting the information via SMS, type SPOT (train number) and send the message to 139).
With RailRadar, passengers can now spot trains on a map by clicking on the blue (on time), yellow (delayed) or red (delayed by more than 15 minutes) arrows that represent individual trains, and know where it is at the moment. By clicking further, one can find out when it will arrive at different stations ahead of it and the time it passed the last few stations en route. In a nutshell, almost real-time (time lags of a few minutes are part of the system though) schedules of a train can be had by clicking on a map.
“Response to RailRadar has been tremendous — not just in India but worldwide. In the first week of its launch, RailRadar was noted as the top talked about map-based application across the world. While there are few additional countries where railways are tracked on a map, reviewers of this site have acknowledged that this has to be the biggest one just based on its sheer size and complexity,” Mr. Rathi said.

Sunita Williams embarks on seventh spacewalk to find ammonia leak

File photo shows U.S. astronaut Sunita Williams, who is scheduled to return to Earth on Nov.19, after a four-month mission.
AP File photo shows U.S. astronaut Sunita Williams, who is scheduled to return to Earth on Nov.19, after a four-month mission.
Indian-American Sunita Williams ventured out of the International Space Station (ISS) with a fellow astronaut on Thursday for a 6.5-hour sojourn, her seventh so far, to fix an ammonia leak in the radiator system.
Two spacewalking astronauts worked on the leaky radiator system outside the ISS, just hours after the vessel barely dodged a menacing piece of orbiting junk.
The U.S. space agency NASA ordered the space station to change position on Wednesday to avoid a fragment from a communication satellite that was destroyed in a high-speed collision three years ago.
Thrusters on a docked Russian supply ship were fired to move the orbiting lab out of harm’s way. But a computer error caused the thrusters to malfunction, and the space station did not reach the desired altitude.
NASA officials said the space station and its six residents were safe despite their lower-than-intended orbit.
Space station commander Sunita Williams and Japanese astronaut Akihiko Hoshide wasted no time installing jumper cables outside their home for the past four months. Their objective was to isolate a suspect radiator to help determine whether that is the source of the ammonia coolant leak and deploy a spare radiator to bypass the troublesome section.
Engineers theorize that bits of space junk may have penetrated the radiator or part of its system; another possibility is that the 12-year-old equipment simply cracked.
The radiators are needed to dissipate heat generated by electronic equipment aboard the space station. Toxic ammonia is used as the coolant, and the spacewalkers took care to avoid contamination.
In an interview with The Associated Press earlier this week, Williams said the biggest risk is the uncertainty surrounding the leak. “We have a lot of extra procedures just in case things don’t go exactly as planned,” she said. “But we’ve dealt with ammonia before.”
A small leak was detected in this area in 2007. Spacewalking astronauts added extra ammonia last year to shore up the system, but this past summer, the leakage increased fourfold. At that rate, the affected power channel could be offline by the end of the year.
That’s why Thursday’s spacewalk was ordered up, even though it comes shortly before the departure of Williams and Hoshide. The two are scheduled to return to Earth on Nov. 19, after a four-month mission.

How cooking helped us become brainier


THE DIFFERENCE: Cooking increases the nutrient content and energy intake in the consumer. Photo: M. Vedhan
THE DIFFERENCE: Cooking increases the nutrient content and energy intake in the consumer. Photo: M. Vedhan
Brain size of humans increased because they began to eat cooked food while the great apes ate everything raw
The internet is abuzz over a recent paper in the October 22 issue of Proc. Natl, Acad, Sci.US (PNAS) by Drs Fonseca-Azevedo and Herculano-Houzel of Brazil. These two ladies have claimed that the enormous increase in the brain size in humans came about because humans began to eat cooked food while our closest cousins, the great apes did not know how to use fire and ate everything raw. They claim that this sudden and large increase in brain size was an important event in human evolutions thanks to the use of fire.
Why do they claim so? We humans have the largest brains in comparison to our body size. Our brain-to-body ratio is far higher than that of the other primates. We have as many as 86 billion brain cells or neurons, compared to just 28 billion in the great apes. This is a giant step in evolution. How and why this sudden expansion came about has been a nagging question. And brain consumes a lot of energy to operate. After skeletal muscles and the liver, it is the brain that consumes most of our metabolic energy. Though it is only about 2 per cent of the total body mass, it consumes 20 per cent of the total body metabolic rate. In other primates, the number is just 9 per cent. To maintain such an energy-expensive organ, the amount of food we need to eat, or more precisely the number of calories we need, is huge indeed.
The needs
The greater the need for calories, the greater the time needed for feeding. This means more time spent on foraging for food and greater time needed for ingestion and digestion, plus of course the calorie content of the diet. And the amount of calorie intake depends on the number of hours spent on feeding and digestion. It has been estimated that gorillas spend about 10 hours a day for feeding themselves. And it is estimated that as they do so, their total body mass goes up to 120 kg or so. The metabolic cost of maintaining such a size of body is estimated by what is known as the Kleiber scale as 70 x (body mass) kilocalories per day. Since brain cells consume a lot of energy, this puts an upper limit to the brain size of an ape. Its brain can grow only if it feeds continuously the whole day.
It is here that raw versus cooked food argument comes in. Dr. Richard Wranghan of Harvard’s Peabody Museum estimated the energetic consequences of raw food and of cooked in his paper in the November 29, 2011 issue of PNAS (Incidentally both this paper and that of the Brazilian duo are downloadable free).
He and his group decided to compare the weight gain of mice fed on raw meat (lean beef) versus cooked meat, and likewise fed on raw tuber (sweet potato) versus pounded, cooked and whole, or cooked and pounded. They found that mice that ate cooked meat gained weight (this gain was not attributable to differences in food intake or activity levels); likewise with processed tuber over raw tuber. Cooked food was seen to be more digestible and also helped in killing pathogens present in the raw samples. He thus writes that adoption of cooking would have helped ancestral humans thrive.
Meat and tubers have been eaten by us for over 2 million years. And when we learnt how to make and tame fire, cooking was born. And cooking increases the nutrient content and energy intake in the consumer. Dr. Wrangham published in 2010 a book entitled: Catching Fire: How Cooking Made us Human. Here he points out that as our hominid ancestors started cooking and eating, their digestive track shrunk and brain enlarged.
Pointed out
The Brazilian ladies build on this point. They point out that the energy intake in cooked food is higher than in raw. And that it costs about 6 kilocalories per day to operate a billion neurons. In a typical daily intake of about 1800 kilocalories, 20 per cent or 360 kilocalories go to operate our brain.
Given these numbers, one can see the value of eating cooked food. In order to get 1800 kilocalories per day on raw food, a human weighing 70 kg would have to spend over 16-18 hours eating! Cooking thus not only would have let early homo erectus gain time away from foraging and eating, but also to think more using the greater brain size he would have gained! Azeredo and Herculano-Houzel thus make a logical case when they say that cooked diet may have been a major positive driving force to the rapid increase in brain size in human evolution.
Comments on the web
As expected, the internet is full of comments and criticism on the above two papers. People who prefer to eat raw food (not just plants, fruits and nuts) have written about how they are perfectly healthy, happy and brainy with raw food; others points out that even this “raw” is processed in one way or the other if it is meat or fish (marinated, fomented).
But such arguments miss the main point, namely, how evolution would have been helped by the use of fire and cooking in providing greater energy and nutritive values, at a crucial time period when several other factors would also have acted to help the emergence of homo erectus, and then on to homo sapiens like us who use our brains to think back in time on how we got our brains this big.

23 Oct 2012

Lack of sleep can slow you down

Peaceful at sleep. Photo: By Arrangement 
Researchers at Brigham and Women’s Hospital (BWH), a teaching affiliate of Harvard Medical School, have found that regardless of how tired you think you are, lack of sleep can influence the way you do certain tasks.
If you sleep only for five to six hours, it is bound to affect your work negatively. Experts recommend eight hours of sleep for ideal health and productivity.
Researchers at Brigham and Women’s Hospital (BWH), a teaching affiliate of Harvard Medical School, have found that regardless of how tired you think you are, lack of sleep can influence the way you do certain tasks.
“Our team decided to look at how sleep might affect complex visual search tasks because they are common in safety-sensitive activities such as air-traffic control, baggage screening and monitoring power plants,” Jeanne F. Duffy at BWH was quoted as saying in the The Journal of Vision.
“These types of jobs involve processes that require repeated, quick memory encoding and retrieval of visual information, in combination with decision making about the information,” added Duffy.
Researchers collected and analyzed data from visual search tasks from a group of participants over one month’s study. In the first week, all participants were scheduled to sleep 10-12 hours per night to make sure they were well rested.
For the following three weeks, the participants were scheduled to sleep the equivalent of 5.6 hours per night and also had their sleep times scheduled on a 28-hour cycle, mirroring chronic jet lag.
The research team gave the participants computer tests that involved visual search tasks and recorded how quickly the participants could find important information, and also how accurate they were.
The longer the participants were awake, the more slowly they identified the important information in the test, the team observed.
Additionally, during the biological night time, 12 a.m. to 6 a.m., participants (who were unaware of the time throughout the study) performed the tasks more slowly than they did during the daytime.

Are Nobel prizes, “a charming anachronism”?


Question of credit: The boson is named after Higgs, who along with five others proposed the mechanism that suggested the particle. A team of 6,000 people proved them right. 
AP Question of credit: The boson is named after Higgs, who along with five others proposed the mechanism that suggested the particle. A team of 6,000 people proved them right.
Every year around this time, when the Nobel prizes are awarded, debates start about who missed out, whether the ones who got them deserved them and so forth. This year, such debates started a month ahead, with columns by well known scientists in journals and newspapers. Professor Athene Donald of Cambridge asked in the 17 September 2012 issue of The Telegraph “how many scientists does it take to make a discovery?” and that the era of the lone genius, as epitomised by Albert Einstein, has long gone.
Well, while Alfred Nobel himself had stipulated that the prize be given to an outstanding discovery made during the year, prizes are today given for discoveries and inventions made much earlier, and their importance realised in time. Also, while it was generally given earlier for a single individual, the Foundation expanded it to three, and no more than three, to share the prize.
Debate is not restricted to the issue of single versus multiple alone. Several more issues concerning the prize have been raised, each worthy of consideration in itself. Not accounting for, or addressing these concerns, has made the journal Scientific American state in its editorial page of October 8, 2012 that, in many ways, the Nobel Prize is a charming anachronism. In other words, it has not kept up with the changed, and changing, landscape and practices of sciences and how it is done.
Some of the issues are: (1) is it for a lone genius, or even a threesome, or should a team not be awarded? (2) Is the stipulation for disciplines (physics, chemistry, medicine) relevant any longer? (3) Why are the rules different for different categories of prizes? (4) Do we have to stick to the “year of discovery” as Nobel wanted? (5) Do we add any more scientific disciplines for recognition? Some of these issues are interlinked.
Many had expected the Higgs Boson (and Peter Higgs) to be recognized by the Prize this year. It was not, and that highlights some of the above issues. The boson is named after Higgs who — along with R. Brout and F. Englert, and with G. S. Guralnik, C. R. Hagen and T. W. B. Kibble — proposed the mechanism that suggested the particle, as early as 1964. And it took a team of 6,000 people, working as the Atlas Collaboration and the CMS Collaboration, at the Large Hadron Collider in Switzerland, to prove them right. Do we then give the six of them or the 6005 of them?
This is not just with the Boson experiment. Many other such grand ideas are done as teamwork. Today’s science has moved from that of a scientist ploughing the lone furrow, into a group, team or consortium of collaborators. The Human Genome project is an excellent example. But then, as a scientist commented on the Scientific American editorial, perhaps awarding organisations, not just individuals, might be an option to consider (which in turn raises its own debate), just as in the case of the Nobel Peace Prize.
Discipline categorisation is another issue that is being debated. During the last 12 years, the Nobel Prize in Chemistry has gone only in four years to ‘card-carrying’ chemists, the rest eight have gone to molecular biologists, structural biologists and biophysicists, and several chemists have wondered about this.
Then again, last year’s prize went to Dr. Schechtman for his discovery of quasicrystals, a topic that could have been just as well included in physics. But, the 2010 Prize for discovering and identifying an allotropic form of the chemical element, graphene, was in physics, not chemistry! This brings the other issue of merging of disciplines blurring of boundaries and the birth of new disciplines. The charm in graphene lies less in its chemistry but far more in its use as a material — and in the new fusion-discipline material science.
Then again, the Nobel people started to award in soft-science areas such as economics. This has made one ask whether there should not be Nobels in time-honoured areas such as biology (as distinct from chemistry) and mathematics.
Other awards
Granted there are other agencies that award much coveted prizes such as the Fields and Abel Prizes in mathematics, Dan David prizes (which are three annual prizes of US$ 1 million each for achievements having an outstanding scientific, technological, cultural or social impact on our world), and the Lasker awards in medicine. Indeed, more often than not, a Lasker awardee ends up getting the Nobel as well; Drs. John Gurdon and Shinya Yamanaka who got the Nobel this year in medicine won the Lasker in 2009 (and Martin Evans won the Lasker in 2001, and the Nobel in 2007). But the esteem that the Nobel has earned over the last century still is its trump card, which is why there is much discussion about its various facets.

That spark of innovation

: Varsshini R. demonstrates her device which generates electricity using mechanical pressure, in Bangalore on Friday. Also seen are Mount Litera Zee School principal Sandhya Sriraman and BrainCafe Karnataka head Sunil N. Photo: K. Gopinathan 
The Hindu : Varsshini R. demonstrates her device which generates electricity using mechanical pressure, in Bangalore on Friday. Also seen are Mount Litera Zee School principal Sandhya Sriraman and BrainCafe Karnataka head Sunil N. Photo: K. Gopinathan
State-level BrainCafe Budding Scientist Contest today
A small spark of a gas stove lighter that her mother used every day was enough for Varsshini R., a Class 6 student at Mount Litera Zee School in Hosur, to create an innovative device that generates electricity using mechanical pressure.
Her new device, made out of a small wooden plank, LEDs and piezoelectric material, was demonstrated at a press conference here on Friday under the aegis of BrainCafe, an activity-based learning programme for schools which is a joint venture of Zee Learn Ltd. and Gakken Educational Co.
How it works
Demonstrating the device, she said it works on the principle that electricity is generated from the electrons released by piezoelectric material when any pressure is placed on it. As it was a cost-effective way of producing electricity, the idea was applicable at public places such as staircases, footpaths and roads, the 11-year-old said.
“My aim is to become a scientist in the future,” the budding scientist added.
Sandhya Sriraman, school principal, said they were implementing the idea in their school to generate their own electricity.
Varsshini’s invention has also made its way to State-level BrainCafe Budding Scientist Contest 2012, which will be held on Saturday at the Insight Academy, 20, Mango Garden Layout, Konanakunte, here.
Forty young scientists from Bijapur, Hosur, Mandya, Mysore, Davangere, Gadag and Shimoga will participate in the event.
The national event, which will be held in November in Mumbai, will see participation from 9,000 students.