SCIENCE TRIBUNE Thursday, February 13, 2003, Chandigarh, India
 


Potable water through solar energy
T.R. Thiagarajan
S
TERILISED drinking water has been a burning problem in the developing countries since a long time. It has been assessed that water-borne diseases claim nearly five million lives annually in Afro-Asian countries. The situation is further aggravated in the event of natural calamities like cyclone and earthquake. 

Bioinformatics Alliance
THE Bioinformatics Research Center (BRC) of the USA and the Center for Development of Knowledge and Awareness (CEDKA) will jointly conduct research and training in the field of multi-disciplinary Bio informatics. Leading scientists from America and India will be involved in the research.

Roll-up screens are coming!
A
new technology that makes cellphone screens glow like a firefly’s tail may well be destined to brighten displays on everything from televisions to digital cameras. Built on organic molecules or polymers that glow when they’re electrified, the technology could even spur the currently unattainable: roll-up computer screens that can fit in a breast pocket or sheets of radiant lighting that shimmer like the aurora borealis.

UNDERSTANDING THE UNIVERSE 
WITH PROF YASH PAL
My doubt is from cricket. Most of the time the Austrian spinner Shane Warne gets more wickets than others do. It is by spinning the ball. What is the science behind his capability to turn the ball through spinning?

NEW PRODUCTS & DISCOVERIES

  • Strange dark matter fills universe

  • Energy from dead animals

Solution to last week’s Crossword

 
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Potable water through solar energy
T.R. Thiagarajan

STERILISED drinking water has been a burning problem in the developing countries since a long time. It has been assessed that water-borne diseases claim nearly five million lives annually in Afro-Asian countries. The situation is further aggravated in the event of natural calamities like cyclone and earthquake. Shortage of chlorinated tablets compound the problem of potable water further.

Swiss Federal Institute for Environmental Science and Technology, Duebendorf, has recently developed an innovative, simple method using solar energy to obtain safe drinking water in such eventualities. It has been discovered that water filled in plastic bottles on exposure to sunlight readily disinfects the water. The method known as "Solar Disinfection" (SODIS) readily warms up the water and the combination of warm water and ultraviolet radiation in the sun destroys most micro-organisms. "SODIS efficiently inactivates bacteria and viruses" asserts project Director Martin Wegelin, a recognised scholar in this area of research. Detailed investigations have shown that 99.9% of the Escherichia Coli (an harmful organism) were killed when a sample of water was exposed to sunlight over an hour reaching beyond 50.0 degrees C. To hasten the process it is suggested to paint half the bottle in black colour and be kept on a corrugated sheets.

Prof Wegelin and his team have carried out extensive tests using SODIS in several villages of Asia, Africa, and South America. The results were quite encouraging. One positive aspect is, this method effectively destroys vibrio cholerae, the dreadful organism that produces cholera. It also inactivates human parasites such as cryptosporidium that causes severe diarrhoea.

This simple technology can be a boon in the urban areas of the developing world where safe drinking water is a rare commodity. This results in perceptible increase of the sales of bottled drinks. "The target population of the soft drinks industry are well off people who buy the bottles. The target population of SODIS are the poor who are interested in empty bottles" he explains. "Bottles go from rich to poor and in a way this reduces the waste accumulation in the urban areas."

This technology has its own shortcomings. Prof Tricia Jackson of the Water Engineering and Development Centre of Loughborough University points out "There may be a dearth of suitable plastic containers during emergencies". Prof Alan Reed, another expert says "lack of awareness among the rural population in developing countries is yet another problem. If there is a little water and people have to trek a long distance to get it, they don’t tend to worry what it contains". Further SODIS can not be employed on a large scale of water. It also requires relatively clear water (turbidity less than 30 NTU) To achieve satisfactory result it is recommended exposure for five hours under bright sunlight or up to 50 per cent cloudy sky, or two consecutive days under 100 per cent cloudy sky.

The author is Retd. Chief Chemist, King Institute of Preventive Medicine, Chennai

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Bioinformatics Alliance

THE Bioinformatics Research Center (BRC) of the USA and the Center for Development of Knowledge and Awareness (CEDKA) will jointly conduct research and training in the field of multi-disciplinary Bio informatics. Leading scientists from America and India will be involved in the research.

The two organisations recently announced an alliance under the research consortium- Joint Indo-American Bioinformatics Alliance (JIABA). Says Dr Mahesh Dutt, Director, CEDKA: "JIABA is our tool to achieve the goal of sharing information as a global player. JIABA offers Indian as well as American scientists a symbiotic association in the field of Bioinformatics. Outcome of this alliance would go a long way to benefit Pharma and IT companies, researchers, and graduates who wish to make a career in Bioinformatics."

Both the organisations will become the nodal agencies for maintaining joint research data that can be used for multifarious applications . CEDKA and its collaborators will initiate a series of projects to establish communication, joint project infrastructure, and cross-program training between the faculty, students and their collaborators in India and America. This effort will further support joint Bioinformatics research and intellectual transfer between the centers, and their collaborators.

The research, which will leverage the expertise of both countries aims to create new technologies and developments. Four projects that have been announced under the project are Protein Sequence and Structure Analysis, Data Mining for Biomedical Research, Disease-Oriented Research and Indian Bioinformatics database development.

"Bioinformatics has become the facilitating discipline to bridge the scientific investigations of the complexity of disease genetics with computer technology and mathematical theory"Dr. Peter Tonellato, Director of Bioinformatics Research Center, said adding, "Coupling technology with high-throughput data collection and the forth-coming discovery paradigm will provide the basis of the new hypothesis-driven discovery research that will lead to breakthroughs in clinical applications of genome discoveries".

Shveta Pathak

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Roll-up screens are coming!

A new technology that makes cellphone screens glow like a firefly’s tail may well be destined to brighten displays on everything from televisions to digital cameras. Built on organic molecules or polymers that glow when they’re electrified, the technology could even spur the currently unattainable: roll-up computer screens that can fit in a breast pocket or sheets of radiant lighting that shimmer like the aurora borealis.

"Imagine a plastic film or a fibre-optic cable that emits light, that you can bend in any shape you want," said Stewart Hough, vice president at Cambridge Display Technologies, "It’s one of those limited-by-your-imagination things."

Hough’s company is developing a polymer-based version of the technology, known as Organic Light-Emitting Diodes or Oleds (a diode being a piece of electronics in which current flows in only one direction).

Chemical, electronics and lighting companies including Kodak, Samsung, Philips, DuPont and others are pouring funds into research and development of Oleds’ rushing tiny screens to market and scrambling to race ahead of competitors.

For now, the monochrome screens appear on a handful of products:cell phones, an MP3 player, car stereos. As the bright new screens mature into full-colour displays with an active matrix that permits video, analysts say they’ll jump to digital camera displays, auto dashboards, laptop screens and TVs.

Global sales of Oleds, estimated at just $ 80 million in 2002, are expected to jump to $ 2.3 billion by 2008.

As Oleds progress, analysts say they’ll replace the silicon-based LCD, or liquid crystal display technology, that’s used in everything from watches and calculators to flat-screen monitors and some TVs. Oled screens are comprised of arrays of tiny diodes made of organic materials used in plastics and polymers. The diodes in today’s little screens are sandwiched between layers of glass, glowing in various colours as electricity flows through them. The delicate organics wither and die at a hint of moisture; so glass is needed to keep them dry. AP

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UNDERSTANDING THE UNIVERSE 
WITH PROF YASH PAL

My doubt is from cricket. Most of the time the Austrian spinner Shane Warne gets more wickets than others do. It is by spinning the ball. What is the science behind his capability to turn the ball through spinning?

There are many spinners who can spin the ball while bowling. Shane Warne has the skill of doing it better and in a more controlled manner. In all this one also has to take the nature of the pitch into account. This is understood if you first know the reason for change in the direction of a spinning ball after it hits the ground. The reason is actually quite simple. When the spinning ball hits the ground it pushes the ground in the direction of the spin. This push is possible because of the friction that ground tends to absorb the momentum of the spin. The equal and opposite reaction of the ground gives the ball a push in the opposite direction. This is what turns the ball, often in an unexpected direction to befuddle the batsman. The skill of great spin bowlers makes use of this aspect of dynamics.

There are other aspects of sport dynamics that skillful players and athletes use through their own discovery. There are many marvelous things we humans learn to do without understanding how we do them. This is the privilege of being human. We do not know how we get the best tunes and tones out of our vocal chords or the instruments we play. Much of art and craft belong in that category. Great bowlers are also artists and craftsmen of sorts.

The Sun produces heat, but the Moon does not. What is the reason?

Amongst the heavenly bodies only the big ones produce energy. The Moon is not big enough to be a star. The Sun is. Mercury, Venus, the Earth, Mars, Jupiter and Saturn, indeed none of the planets generate significant amounts of energy. They are not stars. They get their energy mainly from the Sun, which is the only star of our family. All the planets and the moon shine because of the light they receive from the sun. They just scatter some of the light they receive.

Why does an object have to big enough to become a star? We now understand this reasonably well. Heavenly bodies are not born big. They become so by a lot of matter falling together over a long period of time due to the force of gravity. This falling together leads to collisions and ultimately chaotic motions of atoms and molecules. This chaotic motion is nothing but heat. The inner temperature of the large body can rise to millions of degrees. When that happens, the energy of individual particles is such that nuclear reactions can commence. There is much more to this story and we can get to that if there is interest. For the time being it is enough to say that our Sun was big enough for such nuclear reactions to commence. Indeed the light, heat and energy that we get from the sun is actually the nuclear energy being produced in the centre of the sun. None of the other planets made it to the starting line. Just as well because life would have been very different and difficult with two Suns around.

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NEW PRODUCTS & DISCOVERIES

Strange dark matter fills universe

A powerful new telescope instrument at the South Pole has provided fresh evidence that the universe is accelerating outwards and is dominated by a strange form of matter nobody knows anything about, a new scientific study reveals.

Cosmologists, working in temperatures plunging below minus 73 degree Celsius have detected subtle temperature differences in the cosmic microwave background (CMB) radiation to produce the most detailed images of the early universe ever recorded.

CMB is the remnant radiation that escaped from the repidly cooling universe about 400,000 years after the Big Bang.

The instrument, known as an Arcminute Cosmology Bolomeer Array Receiver (ACBAR), is part of the solar observatory at the US amundsen-Scott South Pole Station.

In a press statement, the US National Science Foundation (NSF) said this provides data to support the currently favoured model of the universe "in which 30 per cent of all energy is a strange form of dark matter that doesn’t interact with light and 65 per cent is in an even stranger form of dark energy that appears to be causing the expansion of the universe to accelerate."

"Only the remaining five per cent of the energy in the universe takes the form of familiar matter like that which makes up planets and stars." — AFP

Energy from dead animals

Swedish companies have developed a way of burning dead farm animals that generates energy while reducing the risk of mad cow disease.

The Swedish Board of Agriculture said it would give $ 276,000 in grants to three companies developing the method, in which cadavers and animal byproducts are incinerated without the traditional step of first grinding them into meat and bone meal.

"We believe that this will be the future way of getting rid of this type of material," said Stig Widell, a spokesman for the state agency. "You just grind them down to minced meat and off they go into the furnace."

Avoiding the step of making meat and bone meal makes the process quicker. It also ensures cadavers and animal byproducts aren’t recycled for animal feed.

Mad cow disease, also known as bovine spongiform encephalopathy, is believed to spread through cattle feed that contains meat and bones from infected animals. AP

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Solution to last week’s Crossword



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