What to avoid after a full meal

 

              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.

QUESTION CORNER

G. KRISHNAMURTHY

Mobile touch screen

How do mobile touch screens work?

RAM POOJAN CHAURASIA

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

 

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             PTI A satellite imagery of India on Diwali night released by NASA. Photo: PTI 
   
   
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                         PTI NASA releases map of India on Diwali night. PTI graphic

  Earth at night

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.

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.

       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

                              

                         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

              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.

Auto-return

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

 

 

 

                               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

 

 

 

                               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.”