Science, society and scientist
by Amar Chandel
To publicise or not to publicise what they are doing is a Shakespearean dilemma that confronts scientists. Left to himself, every serious scientist would perhaps be happy to keep himself closeted in his laboratory or observatory. After all, a purist's view is that publishing diminishes the quality of work — through overclaims and mistaken analogies, etc — and even of the scientist through descending to the common man's level.

Response
I have carefully gone through the contents of the letter of Mr G.S. Dhillon published in the Science Tribune of Feb 11. I stand by the details shown by me in my article as the same have been worked out after taking into account the point raised by Mr Dhillon regarding changes in concrete.

DNA fingerprinting
by Dinesh Kumar

Forensic science is one of the fascinating branches of science. Movies and television serials are made showing how a diligent detective was able to piece together a crime in seemingly impossible circumstances. In real life, however, detectives hardly have the time to solve cases, let alone go in for rigorous research. Many of their techniques are not taken as conclusive evidence. The only positive leads available to forensic science is through fingerprints: since each person has a unique finger-pattern, a criminal can theoretically be nabbed.

Other techniques have not had unequivocal success. But one method is increasingly being used the world over in solving crime cases: DNA fingerprinting. It has been used in thousands of cases since it was used in 1986. In that case, it showed that a person who had confessed to committing a rape had actually not done it and the analysis helped in catching the real culprit. Even in cases where there are no clues, DNA can be collected from minute samples at the scene of the crime which no criminal can wipe out completely.

DNA are strands of genetic material found in tissues and all parts of the body such as blood, skin hair and so on. It is unique for each human being, except in identical twins. If it is picked up from a scene of crime, it can help solve crimes by matching the DNA of suspects. It is thus a foolproof method. The problem was often in obtaining enough quantities of tissue from the scene of the crime which could help establish the DNA profile of the criminal.

In the 1980s, a new technique was invented: the polymerase chain reaction (PCR) technique. This allows DNA analysis to be performed on minute amounts of tissue. It amplifies small quantities of DNA and replicates the molecules. In this technique, first the DNA molecule is exposed to high temperatures, which makes it come apart. An enzyme called polymerase is added to the mixture so that the double helix cannot come together, but forms a new strand. The DNA is thus doubled in the laboratory and the process can be repeated till enough is obtained for proper analysis. The DNA then works like a signature, since the variation among people is concentrated at certain places in their DNA. Another signature is found in DNA microsatellites, which are short segments in which the sequence of the genetic latters repeats itself.

Since the DNA works as a signature for each human being, laboratory results can produce an accurate profile of the DNA of a person. Thus, taking pieces of saliva, hair and semen from the scene of the crime is essential and will become invaluable clues. The next step is to do the DNA fingerprinting of suspects in order to match the results obtained. In cases of rape, getting a victim to a DNA expert would almost certainly establish proof of the involvement of the culprit, since other evidence is hard to come by or is not enough to convict. If DNA databases are maintained of the population, all that needs to be done is to do a computer match of the DNA obtained to zero in on the culprit.

Since building a DNA database for millions of people is a huge task, this may not be possible right as yet. However, obtaining DNA samples of suspects is not a difficult task and crime fighting can be greatly helped through this technique. There have been controversial cases no doubt, but the DNA technique is accepted widely as accurate.

How can our country benefit from the technique? The first step is to create DNA testing facilities in hospitals and forensic laboratories. Researchers must be trained in these techniques. As the incidence of crime is increasing in the country, it is time we started fighting it with modern scientific methods. DNA testing should thus be more widespread than it is now.

The modern forensic detective may not be as romantic as Sherlock Holmes, with a magnifying glass in his hand. He may not be the colourful characters we see on television screens either. He may well be a white coat clad scientist in a laboratory who can identify DNA signatures.

Science, society and scientist
by Amar Chandel

To publicise or not to publicise what they are doing is a Shakespearean dilemma that confronts scientists. Left to himself, every serious scientist would perhaps be happy to keep himself closeted in his laboratory or observatory. After all, a purist's view is that publishing diminishes the quality of work — through overclaims and mistaken analogies, etc — and even of the scientist through descending to the common man's level.

Surprisingly, and fortunately, one of the country's topmost scientists, Jayant Vishnu Narlikar, holds a diametrically opposite view. An interaction at Pune recently provided one an opportunity to discuss the subject with him.

In jest, he explains his "publicise or perish" theory by saying that publicising one's work is necessary not only because a scientist's credibility rests on peer review (which demands publicising) but also because research grants are at stake! But on a more serious note he elucidates the issue through a triangle. The point to note is that each side of it has two-way arrows, signifying two-way interaction.

Take the A-B (science-scientist) side first. Science opens a new door only at the right time, as it happened last century when quantum mechanics and relativity came up after thermodynamics. Science has always attempted to hit at wrong approaches through new findings.

The scientist on his part takes up new challenges of nature to advance the frontiers of science. He uses new ideas for practical purposes.

In science-society interface also, there is two-way communication. Science through its technological inventions controls society whereas society controls science for reasons of survival, politics and commerce.

But perhaps the most important is the scientist-society relationship. The former is dependent on society for continuing his or her work while the latter requires the scientist to work in a certain way for its compulsions.

That makes it imperative for a scientist to publicise his work. A scientist owes it to society in return for its support, according to Professor Narlikar.

Once the necessity of publicising is accepted, the next task is to identify and eliminate the problems of publicising at the right level. The first is how to convey genuine excitement about an advancement, invention or discovery, without succumbing to hype. A glaring example is the almost-monthly announcements about the discovery of a black hole. After all, a black hole can never be really discovered.

Then comes the question of "descending" to the level of the common man. Professor Narlikar calls it "ascending" instead. The way he sees it, most scientists dig deep to find the truth. They have to "ascend" to the ground level to enlighten the layman about what they have found. The trouble is that not all scientists with something to communicate are good communicators. They can reveal their mind to those who are on the same wavelength but are at sea when trying to present it to the common man. Even those who are good are not bothered about communicating, because they are over-eager to avoid public misconceptions.

They cannot be faulted for that either. Besides ensuring that they do not misuse the general public's lack of expertise on scientific matters to inflate their own achievements, scientists have to avoid overkill or backlash because aggressive support for a factual idea, which does not have widespread support, can be counterproductive.

Even when a scientist practises such transparency, there are times when vested interests try to silence him. That is what hurts the most. Even as luminous a mind as Narlikar has had to suffer this ignominy. Some years ago, when he, along with some other prominent scientists, proposed an alternative to the Big Bang theory, the US-based referee rejected it as "outlandish". That is the cross that many a scientist has to bear.

Response

I have carefully gone through the contents of the letter of Mr G.S. Dhillon published in the Science Tribune of Feb 11. I stand by the details shown by me in my article as the same have been worked out after taking into account the point raised by Mr Dhillon regarding changes in concrete.

Mr Dhillon has raised another point that the common user may not be able to verify the type of steel as Tor-40 or Tor-55 without getting it tested. This is not correct. A common user can easily identify any type of steel without getting it tested. There are distinctive marks on the steel bars which don’t seem to be in the knowledge of Mr Dhillon.

While sending the article, I had desired to write another small piece showing guidelines for buying steel. Now that Mr Dhillon has raised this point, I find it my duty to explain these guidelines:

1. A plain mild steel bar can be easily distinguished from a deformed bar. Please note that the technical name of deformed bars is HYSD bars i.e. High Yield Strength Deformed bars while their popular name is Tor steel as its authorised licencees are Tor-Allies Engineering Services Ltd.

2. Tor-40 steel can be easily identified by a close examination of deformed bars. These bars carry the word Tor engraved on the steel bars at every one metre distance.

3. Tor-50 steel bars carry an additional mark ‘50’ or ‘0’ in between every two Tor marks. That is how Tor-40 and Tor-50 can be distinguished.

4. Sometimes Tor-50 bars carry a mark ‘*’ in between every two Tor marks. This star is very easy to locate.

5. Tor-55 steel bars carry an additional mark ‘55’ in between every two Tor marks.

6. All Tor-50 steel bars are painted green for a length of 4 inches at both ends.

7. All Tor-55 bars are painted blue for a length of 4 inches at ends.

8. Tor-40 bars are not at all painted at ends.

9. All defective steel bars are painted red at both ends by the manufacturers.

10. Tor steel licencees supply a test-certificate for any quantity of steel supplied by them. This certificate is so produced that half of it is embossed in readable form while half of it is printed. This is done to avoid misuse of the certificate or to avoid taking out its photocopies.

JAGVIR GOYAL
Bathinda

Software for spastics

An interactive software to help disabled children who cannot use computer keyboards study has been developed by scientists at NIIT in Delhi.

Spastic students can access the computer by touching a disk-shaped pad, by interrupting a light by slightly moving their hands and by making a sound (not speech) with minimum physical effort.

Called I-learn, the English-language software helps students read text, search libraries for information, use calculators, learn basic mathematics and fundamentals of geometry, and enjoy word games.

The software provides laboratory environment through computer simulation to conduct experiments.

It has already been used by the Spastics Society of Tamil Nadu (SPASTN) for teaching upto XIIth standard, J R Isaac, who led the team of developers of the software, told PTI.

“The Ministry of Social Justice and Empowerment is planning to introduce the software in 300 schools for spastics all over the country.”

The software would be very helpful for teaching spastics, who possess a normal brain but cannot hold a pen or pencul write, he said.

It would soon be available in other Indian languages.

The software offers a separate package for teachers too, which includes a user-friendly authoring system to put the courseware into the computer.

Teachers without any computer background can be trained to use the software within five hours, Isaac said.

The disk operating system (DOS)-based software also facilitates group interaction by allowing five to six students to learn simultaneously in a competitive spirit.

The lessons are accessed by individual students at their own pace. An administrative system keeps track of makes and academic records. Users can even enter text.

Isaac and his colleagues have also developed an improved version of the software for the blind in which text is read out to them by an in-built system which also records the answers for evaluation.

Multimedia encyclopaedia

WORLD Book is the world’s best-selling print encyclopaedia. The 22-volume, 14,400-page encyclopaedia boasts of being the most accurate and up-to-date reference work. The 1999 multimedia version brought out in collaboration with IBM lives up to the reputation. Every article from the book version — there are more than 32,500 articles (20,500 on CD and 12,000 on line) — is included. Thousands of pictures, maps, distance calculator, videos, animations and sound clips enhance the learning experience.

The beauty of the multimedia version lies in interactive simulations and virtual reality tours, which bring information to life. One can double-click on any word for an instant definition from World Book’s 225,000-entry unabridged dictionary. Highlighter and Sticky Notes make research easier.

Total coverage of India and related topics has been expanded under the guidance of Prof K.N. Panikkar, Chairman, Archives on Contemporary History and Professor of Modern History, Jawaharlal Nehru University.

The multimedia encyclopaedia comes in two editions, the standard one and a deluxe one. The former has one CD and the latter two. Besides all the features mentioned above, the deluxe edition takes the user on a virtual tour of the San Diego zoo. Then there is a homework tool kit, featuring research, chart, timeline, webpage and Quiz Wizards that make completing homework easier.

Gondwana research

Dispelling earlier notions of a sandy and stony Satpura basin, new research by geo-scientists in Calcutta has revealed that pre-historic Gondwana in Madhya Pradesh actually had a semi-arid climate, a maze of rivers-criss-crossing each other and tender muddy banks.

The findings, which provide new insight into the region’s topography and might influence contemporary theories of evolution of life, also show that concentration of carbon dioxide in Satpura’s Jurassic air was nine times more than current value.

Analysis of the Gondwana rocks has revealed for the first time that Motur formations in the region had a semi-arid climate, head of the research team Tapan Chakraborty told PTI.

Dr P Ghosh, who headed the carbon dioxide concentration studies, compared preliminary results of isotopic analysis of soil carbonates from Denwa and Bagra formation in upper Gondwana with present global standards to find a nine times decrease.

Reporting the finding in the latest ISI annual review, the geological science unit team said reasons and implications of such an enormous carbon dioxide load were yet to be ascertained.

Ancient soil profile of the basin is being analysed with the help of a huge find of fossil wood and vegetation remnants, Chakraborty said.

“We have obtained fossil wood ranging from a metre to 10 cm in length along with calcareous material, mostly impregnated with calcium carbonate,” he said.

The team has also found interesting information on the direction of the various rivers traversing the pre-historic basin.

“Denwa formation appears to record deposition from meandering streams whereas bulk of the Bagra formation probably indicates a braided stream environment,” Chakraborty said.

This, he said, also suggested that the Denwa rivers with fine sediments flowed in the northerly direction and the Bagra ones with high gradient coarse gravel did so in the south-western direction.