SCIENCE AND TECHNOLOGY -2 marker Part 1

Congratulations to all the students who have cleared prelims 2010.With the promise of extending continuous help for your ensuing mains preparation here is the 1 set of 2 markers for science and technology.

1. LBS (Location Based Services)

The US-based value-added service platform provider Telenity is all set to partner a large mobile operator in India to provide technology for introducing Location Based Services (LBS). The service is expected to be launched over the next month.

 LBS enables mobile operators to make use of the geographical position of the subscriber to offer a wide range of services including services to identify a location of a person or object, such as discovering the nearest banking cash machine.

 Location methods-

1.      Control Plane Locating

Sometimes referred to as positioning, with control plane locating the service provider gets the location based on the radio signal delay of the closest cell-phone towers (for phones without GPS features) which can be quite slow as it uses the 'voice control' channel. 

·         In order to provide a successful LBS technology the following factors must be met:

·         Coordinates accuracy requirements that are determined by the relevant service;

·         Lowest possible cost;

·         Minimal impact on network and equipment.

Several categories of methods can be used to find the location of the subscriber. The simple and standard solution is GPS-based LBS. Sony Ericsson's "NearMe" is one such example. It is used to maintain knowledge of the exact location, however can be expensive for the end-user, as they would have to invest in a GPS-equipped handset. GPS is based on the concept of trilateration, a basic geometric principle that allows finding one location if one knows its distance from other, already known locations.

2.      GSM Localization

GSM localization is the second option. Finding the location of a mobile device in relation to its cell site is another way to find out the location of an object or a person. It relies on various means of multilateration of the signal from cell sites serving a mobile phone. The geographical position of the device is found out through various techniques like time difference of arrival (TDOA) or Enhanced Observed Time Difference (E-OTD).

3.      Others

·         Another example is Near LBS (NLBS), in which local-range technologies such as Bluetooth, WLAN, infrared and/or RFID/Near Field Communication technologies are used to match devices to nearby services. This application allows a person to access information based on their surroundings; especially suitable for using inside closed premises, restricted/ regional areas.

·         Another alternative is an operator- and GPS-independent location service based on access into the deep level telecoms network (SS7). This solution enables accurate and quick determination of geographical coordinates of mobile phone numbers by providing operator-independent location data and works also for handsets that are not GPS-enabled.

·         Many other Local Positioning Systems are available, especially for indoor use. GPS and GSM don't work very well indoors, so other techniques are used, including Bluetooth, UWB, RFID and Wi-Fi.

2. NORIN 10 WHEAT

Norin 10 is a semi-dwarf type of wheat, with very large ears, which was bred in the experimental station of Iwate Prefecture, Japan. In 1935, it was registered as a numbered cultivar by Forestry. Norin 10 grew just two feet tall, instead of the usual four, which made it less prone to wind-caused damage.

Norin 10 provided two very important genes, Rht1 and Rht2 that resulted in reduced-height wheat’s, thus allowing better nutrient uptake and tillerage (when heavily fertilized with nitrogen, tall varieties grow too high, become top-heavy, and lodge).

Developed by Cecil Samon in Japan these samples were used in 1952 by Norman Borlaug and collaborators and crossed with Mexican traditional varieties. They obtained the high-output varieties which were tested in India (Lerma Rojo 64 and Sonora 64) during the green revolution.

Norin 10 helped developing countries, such as India and Pakistan to increase the productivity of their crops from approximately 60% during the green revolution.

3. CARBON FOOTPRINT

A carbon footprint is "the total set of greenhouse gases (GHG) emissions caused by an organization, event or product" .For simplicity of reporting, it is often expressed in terms of the amount of carbon dioxide, or its equivalent of other GHGs, emitted.

The concept name of the carbon footprint originates from ecological footprint discussion. The carbon footprint is a subset of the ecological footprint and of the more comprehensive Life Cycle Assessment (LCA).

An individual, nation, or organization's carbon footprint can be measured by undertaking a GHG emissions assessment. Once the size of a carbon footprint is known, a strategy can be devised to reduce it, e.g. by technological developments, better process and product management, changed Green Public or Private Procurement (GPP), Carbon capture, consumption strategies, and others.

The mitigation of carbon footprints through the development of alternative projects, such as solar or wind energy or reforestation, represents one way of reducing a carbon footprint and is often known as Carbon offsetting.

4. LIDAR

LIDAR is a topographical sensing system. LIDAR makes precise measurements with laser pulses and complements the other modalities in 3-D layered image maps. Recovery crews will use the information in the reconstruction of Haiti.

1.      Thermal imaging provides relief and recovery agencies with critical insight not available from standard color photography. For example we can tell how much liquid is in a storage tank with a thermal camera. We can also make inferences of tanks that are full, tanks that are empty and tanks that are leaking.

2.      The LIDAR capability detects and measures collapsed buildings and standing structures damaged by the earthquake. LIDAR can also be used to map the fault line to estimate how much the earth moved. This information is critical to refinement of earthquake-risk prediction models.

5. DIGITAL IMAGING

Digital imaging or digital image acquisition is the creation of digital images, typically from a physical scene. The term is often assumed to imply or include the processing, compression, storage, printing, and display of such images.

Digital imaging was developed in the 1960s and 1970s, largely to avoid the operational weaknesses of film cameras, for scientific and military missions including the KH-11 program. As digital technology became cheaper in later decades it replaced the old film methods for many purposes.

A digital image may be created directly from a physical scene by a camera or similar devices. Alternatively, it may be obtained from another image in an analog medium, such as photographs, photographic film, or printed paper, by an image scanner or similar device. Many technical images—such as those acquired with topographic equipment, side-scan sonar, or radio telescopes—are actually obtained by complex processing of non-image data. This digitalization of analog real-world data is known as digitizing, and involves sampling (discretization) and quantization.

Finally, a digital image can also be computed from a geometric model or mathematical formula. In this case the name image synthesis is more appropriate, and it is more often known as rendering.

Digital image authentication is an emerging issue for the providers and producers of high resolution digital images such as health care organizations, law enforcement agencies and insurance companies. There are methods emerging in forensic science to analyze a digital image and determine if it has been altered.

6. PROBIOTICS

Of late, there has been a buzz in the media about ‘probiotics’. Probiotics are the ‘healthy bacteria’. It may appear quite like an oxymoron as good health is not usually associated with bacteria.They are ‘live’ micro-organisms, which when administered in adequate amounts, confer a health benefit on the host. If you are wondering how one can knowingly take in live bacteria, there are a few more facts to surprise you…

What are the benefits of healthy bacteria?

The resident bacteria (also called commensals) help guard the body against pathogenic bacteria. Of the many resident beneficial bacteria, lactobacillus has been the most widely studied. Lactobacillus strains prevent the adhesion and growth of urinary and intestinal pathogens and produce high concentration of hydrogen peroxide and lower the pH of the intestine, making it inhospitable for the harmful bacteria.

What causes disturbance in the intestinal flora?

Intestinal flora may be disrupted sometimes due to factors like prolonged use of antibiotics, stress and most importantly diets high in sugar and simple carbohydrates. Exposure to radiation and parasitic infestation may be the other causes. This precisely is the reason why probiotic preparations are sometimes recommended after a course of antibiotics, or as part of treatment.

Which probiotics are helpful?

Among the probiotics, S. boulardii, E. faecium and Lactobacillus sp. are useful in preventing antibiotic-related diarrhoea. Lactobacillus GG reduces the severity and duration of rotavirus diarrhoea in infants. Some lactic acid bacteria have immuno-regulatory effects that might protect against some allergic disorders. There is some evidence that some of these probiotic strains can reduce the intestinal inflammation associated with some food allergies. Some animal experiments have even shown that products containing L. acidophilus have cholesterol lowering effect. In addition, probiotics improve absorption of nutrients, improve synthesis of vitamins and essential fatty acids and also prevent some bacterial and yeast infections.

How do we take in healthy bacteria?

The best way is through dietary sources. In fact, for centuries our native diets have had a good proportion of fermented foods, some of which have probiotic health benefits. Curd, the lactobacillus fermented product, has also been part of the Indian diets for centuries. Similarly pickles, dhokla, butter, are also good sources.

What are the probiotic preparations available in the market?

Food products or supplements and pharmaceutical preparations containing viable probiotic strains are available in the market either as fermented foods or in lyophilised (freeze-dried) form.

A probiotic preparation can be effective only if the healthy bacteria are available in required concentration for consumption; there are concerns about the preservation of probiotic strains in these products and hence there are doubts about their health effects after consumption.

Can probiotics be liberally consumed by everyone?

Studies show that probiotics are contraindicated in those who are proven to be hypersensitive to such products. It is better that pregnant and nursing women use probiotic nutritional supplements only on the physician’s advice. Similarly, the use of probiotics for the treatment of any disorder must be medically supervised. Some commercial foods, which are being marketed as containing probiotics are very high in sugar and are empty calories (poor in vitamins and minerals). Such foods may be unhealthy because of their ‘junk’ nature.

Regulatory Issues?

There is a need for standardisation in order to sift the genuine products from the artificial ones. Considering this, the Indian Council of Medical Research (ICMR), Ministry of Health has recently set up a committee to formulate guidelines for the probiotic foods.

Once the guidelines are out, the products claiming to be probiotic should go through stringent quality checks and disclosure on the labels so that the consumers can make more informed choices.

7. BIOSENSORS

A biosensor is a device for the detection of an analyte that combines a biological component with a physicochemical detector component.

It consists of 3 parts:

§  the sensitive biological element (biological material (eg. tissue, microorganisms, organelles, cell receptors, enzymes, antibodies, nucleic acids, etc), a biologically derived material or biomimic) The sensitive elements can be created by biological engineering.

§  the transducer or the detector element (works in a physicochemical way; optical, piezoelectric, electrochemical, etc.) that transforms the signal resulting from the interaction of the analyte with the biological element into another signal (i.e., transducers) that can be more easily measured and quantified;

§  associated electronics or signal processors that are primarily responsible for the display of the results in a user-friendly way

With most people becoming conscious and aware of the quality of food, water and medicine, biosensors have started to play an important role in our lives. They are fast becoming an important tool in research and commercial applications as they can identify specific targets in the human body and environment. Glucose monitoring is familiar to most of us. Researchers are now working on remote sensing of airborne bacteria in bio-warfare, detection of pathogens, determining levels of toxic substances before and after bioremediation, routine blood urine analysis, drug residues in food and the human body.

·         While human senses provide essential information about our close environment, researchers are looking for new sensors that will give us an analysis of the food we eat, the water we drink and the air we breathe. This requires novel chemical sensors, molecular recognition and signal transduction. Electrochemical sensors have caught the interest of the industry because of their remarkable ability in detection, experimental simplicity and low cost.

·         The Department of Applied Chemistry at CUSAT,Cochin   has been working on electrochemical sensors to detect metal ions and drugs in the human body. Working on research projects funded by the Defence Research and Development Organization (DRDO), the team has made biosensors to detect metal ions and drug residues. The CUSAT has completed Fabrication of potentiometric sensors for the determination of metal ions’ and DRDO, got the next project, ‘Development of electrochemical sensors for the determination of pharmaceuticals, which has been completed.

8. OIL CLEANING BACTERIA

Scientists have discovered new bacteria to combat the oil spill in Mexico.The "NY3" bacteria have an "extraordinary capacity" to produce rhamnolipids that can help break down oil and then degrade some of its most serious toxic compounds. The rhamnolipids, which is non-toxic to microbial flora, human beings and animals, can help degrade polycyclic aromatic hydrocarbons (PAHs), a carcinogenic and mutagenic compound released with the oil spill.

Some of the most toxic aspects of oil to fish, wildlife and humans are from PAHs .They can cause cancer, suppress immune system, cause reproductive problems and damage nervous system. According to experts, the rhamnolipids produced by NY3 strain appear to be stable in a wide range of temperature, pH and salinity conditions, and strain NY3 aggressively and efficiently degrades at least five PAH compounds of concern. 

The search for safe and efficient methods to remove environmental pollutants is a major impetus in the search for novel biosurfactant-producing and PAH-degrading microorganisms.

9. SOLAR FLARES SHINE LIGHT ON MOON MINERALS

In its 10-month orbit around the moon, Chandrayaan-1’s X-ray Spectrometer (C1XS) has detected titanium, confirmed the presence of calcium, and gathered the most accurate measurements yet of magnesium, aluminum and iron on the lunar surface.

This was made possible by 30 solar flares that acted like “flash bulbs” illuminating the surface, The results were presented at the European Planetary Science Congress in Potsdam, Germany.

‘MOST ACCURATE PROBE’

Previous lunar probes detected some of these minerals on the lunar surface, but none as accurately as the C1XS X-ray spectrometer.

The miniature C1XS instrument investigated the lunar surface using an effect whereby X-ray illumination from the sun causes rocks to fluoresce, emitting light at a different wavelength. This re-emitted light contains spectral peaks that are characteristic of elements contained in the rock, revealing its composition.

While C1XS detected magnesium, aluminium and silicon during normal conditions, the instrument could detect calcium, iron, titanium, sodium and potassium in key areas in the southern hemisphere and on the far side of the Moon during the solar flares, the statement said. It added that the spectral resolution of 50 km was much better than previous missions.

The C1XS team will analyse the data collected during the Chandrayaan-1 mission over the next few months, and the results will help us further our knowledge of the Moon and planetary formation.

Scientists were able to separate clear peaks for each of the target elements allowing them not only to identify where they are present but give an accurate estimate for how much is there,” he said.

10. ROBODOG –latest war weapon.

Modern battlefields may soon resemble something out of a science fiction flick, thanks to advances in robotics. The latest weapon to be unveiled is the robodog — four-legged, petrol-powered robots.

Scientists have developed the ‘BigDog’, billed as “the most advanced quadruped robot on Earth,” which they claim is able to carry up to four packs of military equipment on awkward terrain unsuitable for vehicles. Standing at over two feet tall and more than three feet long, BigDog comes equipped with all manner of high-tech gadgets. These include laser gyroscopes, a video camera sensor system and a sophisticated on-board computer.

11-stone machine can trot along at up to four miles per hour and would even stay on its legs when it is kicked hard in the side .In fact, its legs are designed to work in a similar way to a real dog’s, even storing energy in shock absorbers when a foot touches the ground.

The 14-million-pound BigDog is being tested to carry the soldiers’ equipment to prove that it can cope with holes, steep slopes and water hazards. It will also be used in non military purposes in the future.