November 2012

‘LAB ON A CHIP’ MAY MAKE ANALYTIC DEVICES MORE EFFICIENT

A technique that uses acoustic waves to sort cells on a chip may help create miniature medical analytic devices and lead to cell phone-sized medical labs, according to a team of researchers. The device uses two beams of acoustic— or sound — waves to act as acoustic tweezers and sort a continuous flow of cells on a dime-sized chip, said Tony Jun Huang, associate professor of engineering science and mechanics, Penn State. By changing the frequency of the acoustic waves, researchers can easily alter the paths of the cells. Huang said that since the device can sort cells into five or more channels, it will allow more cell types to be analyzed simultaneously, which paves the way for smaller, more efficient and less expensive analytic devices. “Eventually, you could do analysis on a device about the size of a cell phone. It’s very doable and we’re making in-roads to that right now,” said Huang. Biological, genetic and medical labs could use the device for various types of analysis, including blood and genetic testing, Huang said.

CELL-SORTING DEVICES

Most current cell-sorting devices allow the cells to be sorted into only two channels in one step, according to Huang. He said that another drawback of current cell—sorting devices is that cells must be encapsulated into droplets, which complicates further analysis. “Today, cell sorting is done on bulky and very expensive devices. We want to minimize them so they are portable, inexpensive and can be powered by batteries,” said Huang. Using sound waves for cell sorting is less likely to damage cells than current techniques, Huang added. In addition to the inefficiency and the lack of controllability, current methods produce aerosols, gases that require extra safety precautions to handle. The researchers created the acoustic wave cell-sorting chip using a layer of silicone — polydimethylsiloxane. According to Huang, two parallel transducers, which convert alternating current into acoustic waves, were placed at the sides of the chip. As the acoustic waves interfere with each other, they form pressure nodes on the chip. As cells cross the chip, they are channeled toward these pressure nodes. The transducers are tunable, which allows researchers to adjust the frequencies and create pressure nodes on the chip. The researchers first tested the device by sorting a stream of fluorescent polystyrene beads into three channels. Prior to turning on the transducer, the particles flowed across the chip unimpeded. Once the transducer produced the acoustic waves, the particles were separated into the channels.

LEUKEMIA CELLS

Following this experiment, the researchers sorted human white blood cells that were affected by leukemia. The leukemia cells were first focused into the main channel and then separated into five channels. The device is not limited to five channels, according to Huang. “We can do more. We could do 10 channels if we want, we just used five because we thought it was impressive enough to show that the concept worked,” Huang said. The researchers released their findings in the current edition of Lab on a Chip.

AUSTRALIAN SCIENTISTS UNVEILED THE COLOSSAL RADIO TELESCOPE

Australian Scientists unveiled a colossal radio telescope with abilities of exploring the depths of universe with unparalleled precision. The telescope will increase the abilities of astronomers in mapping black holes, survey the universe, and cracking the new light across the galaxies to an exponential level.

At present the Australian SKA Pathfinder telescope having 36 antennas with diameter of 12 meters each is placed at the remote Murchison Radio-Astronomy observatory in the deserts of West Australia. Designed and developed by making investments of Australian $ 140 million has facilities of surveying the sky at a much faster speed than any other telescope available in the world. The sensitive antennas of the telescope are quite sensitive to the faint radiations of Milky Way hence is able to detect the galaxies far away. The radio waves generated from this telescope can provide details of the cosmos far away and the gases that resulted in the formation of any particular star. Pulsars and quasars can also be identified by the telescope with an ease pushing forward the boundaries of knowledge of the mankind ahead of the physical laws of nature. The principle of radio-astronomy can provide the details of the beginning of the universe. Basically the antennas of the telescope spread across the rocky terrain would be used for collection of the radio signals of the cosmic phenomenon. Being 50 times more powerful, when compared to other radio devices, it can easily detect the exploding stars. Hence can be of a great use in establishing the facts related to the formation of the universe that happened about 14 billion years ago.

MAJOR BREAKTHROUGH IN MICROCHIP TECHNOLOGY

IBM scientists are reporting progress in a chip-making technology that is likely to ensure the shrinking of the basic digital switch at the heart of modern microchips for more than another decade. The advance, first described in the journal Nature Nanotechnology on Sunday, is based on carbon nanotubes, exotic molecules that have long held out promise as an alternative material to silicon from which to create the tiny logic gates that are now used by the billions to create microprocessors and memory chips.

The IBM researchers at the T.J. Watson Research Centre in Yorktown Heights, New York, have been able to pattern an array of carbon nanotubes on the surface of a silicon wafer and use them to build chips that are hybrids of silicon and carbon nanotubes with more than 10,000 working transistors.

Against all expectations, the silicon chip has continued to improve in both speed and capacity for the last five decades. In recent decades, however, there has been growing uncertainty over whether the technology will continue to improve. The end of the microelectronics era would inevitably stall a growing array of industries that have fed off the falling cost and increasing performance of computer chips. Chip makers have routinely doubled the number of transistors that can be etched on the surface of silicon wafers by routinely shrinking the tiny switches that store and route the ones and zeros that are processed by digital computers. They have long since shrunk the switches to less than a wavelength of light

The process has been characterised as Moore’s Law, named after Gordon Moore, the Intel co-founder, who in 1965 noted that the industry was doubling the number of transistors it could build on a single chip at routine intervals of 12 to 18 months. To continue the process, semiconductor engineers have had to consistently perfect an array of related manufacturing systems and materials that continue to perform at an ever tinier scale. In recent years, while chip makers have continued to double the number of transistors on microprocessors and memory chips, their performance, measured as “clock speed,” has largely stalled. This has forced the computer industry to change its design and begin building more parallel computers.

PACKING 10 TERABITS ON A TINY DEVICE

A new discovery may open the way for the development of next generation data storage devices with capacities of up to 10 terabits (10 trillion bits) per square inch. An ultra-smooth surface may be the answer, according to a discovery by the researchers from Agency for Science, Technology and Research’s (ASTAR) Institute of Materials Research and Engineering (IMRE) and the National University of Singapore (NUS), reports the journal Nature. The self-assembly technique is one of the simplest and cheapest high-volume methods for creating uniform, densely-packed nanostructures that could potentially help store data, according to an ASTAR statement. However, attempts to employ self-assembly on different surface types, such as magnetic media used for data storage, have shown varying and erratic results to date.

This phenomenon has continued to puzzle industry researchers and scientists globally. The researchers have now solved this mystery and identified that the smoother the surface, the more efficient the self-assembly of nanostructures. The method can now be used on more surfaces. A height close to 10 atoms, or 10 angstroms, is all it takes to make or break self-assembly,” said M.S.M. Saifullah, one of the key researchers.

WASTE DEGRADATION BY WHITE ROT FUNGUS

Composting is a natural process of rotting or decomposition of organic matter by microorganisms under controlled conditions. Raw organic materials such as crop residues, animal wastes, food garbage, some municipal wastes and suitable industrial wastes after composting enhance their suitability for application to soil as a fertilizing resource. In addition to being a source of plant nutrient, compost also improves the physiochemical and biological properties of the soil.

As a result of these improvements, the soil becomes more resistant to stresses such as drought, diseases and toxicity. Composting helps the crop in improved uptake of plant nutrients and possesses an active nutrient cycling capacity because of vigorous microbial activity indirectly leading to pathogen suppression in soil. These advantages manifest themselves in reduced cropping risks, higher yields and lower outlays on inorganic fertilizers for farmers. In recent years, decomposition of agricultural wastes such as coir pith, banana sheath (dried), sugarcane trash, millets and pulse waste, cotton stubble with white rot fungus (Pleurotus sp.) is gaining importance. These wastes are decomposed with any one of the white rot fungi P. eous, P. platypus, P. djamor or P. sajorcaju by layer system. One layer of agricultural waste at 100 kg is spread uniformly in an area of 4 x 3 m2 under shade. Culture of P. djamor at 200 gms is applied over the substrate. Another 100 kg of substrate is spread over the first layer and urea is applied at rate of one kg to the substrate. This sandwiching is repeated to make a heap of 1,000 kg substrate with such 20 layers. A total of one kg of the fungus and five kg urea is required to decompose 1,000 kg waste. Water is sprinkled twice a day to maintain 50 -60 per cent moisture level. The heap is allowed to decompose for a month after which a turning is done. The waste undergoes degradation within 45 days. It has a narrow carbon : nitrogen ratio of 20:1 which can be used as organic manure.

NEW EARTH SIZED PLANET DISCOVERED IN NEIGHBORING SOLAR SYSTEM

Astronomers have discovered a new earth sized planet in October 2012 which is closest to but outside our solar system. The planet is said to be astronomical stone’s throw away at four light years. The discovery of planet was announced in Science Journal, Nature by Stephane Urdy and Xavier Dumusque at Geneva Observatory.

The planet is very close to its sun that it is difficult to support life there. The planet is of very low mass and have a surface temperature of about 1200 degree Celsius (2192 Farenheit).The Planet orbits one of the suns in Alpha Centauri, roughly 25 trillion miles away. Also according to the previous study by different scientist if one planet is discovered orbiting a sun there is usually other planet in the same solar system. Almost 800 exoplanets are discovered in the recent past that is outside our solar system since early 1990’s. But this Planet is very close to earth. It was also asserted that getting to the planet is nearly impossible because it would take about 40000 years to travel to new planet even with current Propulsion Technology

PROCESS OF FRUIT RIPENING AND CHANGE OF COLOURS

Several major changes can take place as fruits ripen. Not all occur in every type of fruit, but taken collectively they characterize ripening processes. They include: (1) a rise in respiration rate; (2) production of ethylene; (3) flesh softening; (4) appearance of colour; (5) formation of volatiles with associated development of flavour.

Among these changes, formation of bright colour, which evolved to attract dispersal agents such as birds, browsing animals and primates, now becomes a particularly important visible indicator of maturity and ripeness. Pome fruit, stone fruit, tomatoes, mangoes and straw berries provide good examples where colour is a prime indicator of ripeness. The non-greening of leaves is called senescence. As in leaf senescence, ripening in fruits also involves chlorophyll loss and an increase in production of yellow, orange, red or purple pigments. Yellow, orange or red pigmentation, as seen in oranges and tomatoes, arise from conversion of chloroplasts to chromoplasts. In higher plants, carotenoids which are found in chromoplasts and anthocyanins which are located in the vacuoles fulfill an important purpose as colorants of fruits.

For example the red colour of tomato (Lycopersicon esculentum) fruits is due to the carotenoid pigment lycopene, whose concentration increases dramatically during the ripening process. The deep yellow colour of mango fruits is due to the presence of beta carotene a common phytochemical within a group of 600 known carotenoids. Similarly the red colour development in apples and purple colour development in grapes are due to the formation of anthocyanin pigments in their skin. Sometimes both types of pigments can occur in the same fruit.

These pigments are formed as end products of two separate pathways during ripening. The phytoene pathway, which leads to the accumulation of yellow-orange carotenoids or red lycopene and the anthocyanin pathway which leads to the accumulation of anthocyanins in the vacuoles are these two pathways.

TWO LABOUR-SAVING FARM MECHANISATION INNOVATIONS

Compared to human labour, using machines is always an easier option for agricultural activities. But the problem arises when farmers are not able to locate or source the right machine on time. Even if they are available their price is either too costly or if on hire, one needs to wait to use them.

A fabricator cum mechanic, Mr. Gurmail Singh Dhonsi from Rajasthan, has developed two agricultural machineries which he claims are easy to use and light on the pocket. The first machine is a tree pruner that can be mounted on a tractor.

The machine can be used for orchard owners like mango growers who need to prune their trees every year.

COMPOST AERATOR

Another machine which he has devised is called compost aerator. “I got the idea to develop this machine by closely observing the earthworms that keep turning the soil,” says Mr. Gurmail Singh. “The aerator is also tractor- mountable and consists of a rotating shaft on which several steel blades are fitted to mix the bio wastes thoroughly.” The machine can be attached to any make and model of tractor of size 50 hp or above. The rotor, which is 16 inches in diameter, is nine feet long. “The nine-inch blades break and chop the bio wastes into very small particles. A hydraulic jack is provided to facilitate the up and down movement of the main rotor. There is provision for attaching a 1,500 litre capacity water tank to the tractor. This water is used to moisten the compost while the rotor blades turn the heap of biowastes. “A weight box has been provided next to the water tank to maintain balance during movement,” explains Mr. Gurmail Singh. While the rotor rotates and the blades cut the biowaste, water is automatically added to the mixture from the tank to moisten it. The tractor is slowly made to run from one end of the heap to the other.

FUEL CONSUMPTION

“This operation needs to be repeated four to five times for five days during summer and seven days during winter. As a result the total time for converting biomass into manure reduces to 25-40 days, as against 120-150 days using manual methods. “For the operation the machine consumes 3.5-4.0 litre of diesel per hour,” he says. According to Dr. Nitin Maurya, National Innovation Foundation, Ahmedabad, the technologies for thoroughly mixing compost for rapid composting are available in many foreign countries although no such domestic product is available.

PATENT FILING

Moreover, the provision of providing moisture while turning biomass is rare and accordingly NIF has filed a patent for this machine in the name of Mr. Gurmail Singh. The compost made by the aerator has been tested by soil testing laboratory at the Agriculture Research Station (ARS) Durgapura, Jaipur. The percentages of nitrogen (N), phosphorus (P) and potash (K) were found to be 1.87, 1.79, 2.26 respectively as compared to 0.4-1.5, 0.3-0.9, 0.3-1.9 per cent in the conventional farm yard manure. This compost was found to be even better than vermicompost. Similar results have also been reported by a private fertilizer company which studied the aerated compost.

GOLD PRODUCING BACTERIA DISCOVERED BY SCIENTIST

Scientist and Researchers from the Michigan State University had discovered bacteria that can tolerate immense amount of toxicity and can also create 24 carat gold. The researchers found that the bacteria named ‘Cupriavidus metallidurans’ is metal tolerant bacteria which can grow on huge concentration of gold chloride which itself is a very toxic chemical compound found in nature.

The researchers fed the bacteria with mismatched amounts of gold chloride, intimating the process they believe happens in nature. In about a week, the bacteria transformed the toxins and produced a gold nugget. The researchers used a combination of biotechnology, art and alchemy to turn liquid gold into 24-carat gold. It is now being called as Microbial alchemy - transforming gold from something that has no value into a solid, precious metal that’s valuable.

CHESHIRE CATS AND WATER SOLUBLE ELECTRONIC DEVICES

We are all familiar with electronic devices such as integrated circuits, chips and tools that do a hundred useful things. They have become inseparable from our lives. What do we do once we are done with them? Throw them away, causing what has come to be known as e-waste. It is estimated that e-waste alone accounts for over 70 per cent of toxic wastes currently found in landfills, and we are yet to get a good estimate of how much it is in the seas and oceans. Again, we use electronic devices such as pacemakers and other sensors that are implanted in our bodies. The trouble with them is that once they are past their use, we need to surgically remove them (and perhaps implant a fresh one). How nice it would be if only they dissolve away and get removed from the body; much the way we discard our body liquids and solids every day! Yes, it appears possible to do so with the development of a prototype electronic chip that is made to work for a defined period of time, which is implanted into a body and dissolves after use and gets excreted away from the body after it has done its intended job.

Dr. John Rogers of the Material Sciences department of University of Illinois at Urbana-Champaign and his group teamed up with Dr. Fiorenzo Omenetto of the Biomedical Engineering department of Tufts University in Boston, and devised an implantable electronic thermal therapy device which lasts inside a rat’s body for a few weeks before dissolving away. They report this landmark work in the 28th September 2012 issue of Science . In order that the device is water-soluble, every component in there must be made of molecules and materials which are water-soluble, not the conventional aluminium, rare-earth metal compounds or plastic stuff that are built to last forever. They must be built to stay and work for a stipulated time and then be washed away. Hence, they used magnesium or Mg as the electrical conductor, MgO and Silicon dioxide as dielectrics, specially fabricated nanomembrane silicon semiconductor and so forth, in order to build the electrothermal device. The entire device including all of its inductor, capacitor, resistor, diode and transistor dissolves away when placed in deionized water. Next, they packed this device in a sheet of silk, which is specially made so as to stay intact for a set period of time, after which it dissolves in the body water, exposing the electronic device which too dissolves away. Here then is the ‘proof of principle’ – a silicon-based complementary metal oxide semiconductor (CMOS) device that is an implantable medical device, which can be custom-made or programmed to last for a defined period of time, after which it is resorbed in the body, so that no second intervention for retrieval of the device is needed.

The device they made was meant to be a heater – one that can be placed next to a site where a surgical operation has been done. It is meant to keep the area warmer so as to keep it free of infection from germs. They first implanted it sub-dermally (under the skin) of some mice. After the programmed three weeks, the implant dissolved away. Only a faint residue was left, which too cleared away, with no inflammation or any side effects. Reassured of its safety, they next implanted this transient thermal therapy device on rats through surgery. Weeks later, they found no traces of infection after the surgery. Here then is the proof of principle. Such biodegradable electronic devices can have many uses. They can be sensors placed in fields, reporting what they are meant to, and fade away. One can, in principle, even make portable consumer devices (cell phones?) which, after use, can be dissolved away in water and the starting material retrieved after evaporating the water. Lewis Carroll used the term Cheshire Cat, apparently after the practice of dairy farmers in Cheshire who would pack and mould cheese in the form of a smiling cat. The cheese was cut and eaten from the tail side of the cat, leaving the smile for last. In any event, Carroll was pre-scient; Cheshire Cats are now an electronic reality.

SCIENTISTS DEVELOPED TEST TO DETECT SCHIZOPHRENICS

Scientists developed a near to 100 percent accurate test to detect schizophrenics, by simply checking their gaze. Apparently schizophrenics can be checked just by implying some ‘simple viewing tests’. The tests brought out ninety eight per cent accuracy in distinguishing between those with and without schizophrenia. This path breaking research was done by researchers at Aberdeen University. They found that people with schizophrenia showed well-documented deficits in the ability to track slow moving objects smoothly with their eyes. The study was led by Dr Philip Benson and Professor David St Clair which involved a range of eye tests and the volunteers were asked to track slow moving objects slowly with their eyes, inspect a variety of everyday scenes and given instructions to keep a steady gaze on a single unmoving target.

EFFICIENT WAY TO TURN WASTE INTO RESOURCE

A staggering amount of waste is generated every day in every town and city, and the local bodies are grappling with logistics for its disposal. The problem arises as the government and individuals fail to see waste as a potential source of energy and agricultural input in the form of manure.

The Bangalore Corporation, which recently made waste segregation mandatory at the household level, is showing the way for the rest of India. It is setting up 12 Nisargruna biogas plants across the city to convert biodegradable waste into methane and organic manure. The Nisargruna biogas plant is based on technology developed by the Mumbai-based Bhabha Atomic Research Centre (BARC). Such plants are being constructed at local levels too. Tata Consultancy Services (TCS) is planning to construct 4 tonnes a day capacity biodegradable waste conversion plant at its sprawling centre at Siruseri IT Park near Chennai. It already has similar plants operating at other locations. IIT Madras has already cleared a project for a plant with 1 tonne per day capacity. The Chennai Corporation recently initiated preliminary discussion with BARC. These are not the first plants coming up in the country. “Such plants have already been installed at 146 locations,” says Dr. S. P. Kale, Head of Technology Transfer & Collaboration Division at BARC. “We have transferred the technology to 100 private entrepreneurs.” In a broad sense, the principle is similar to that of gobar gas plants, but all comparisons end there — the technology is much more advanced and more methane is produced.

BETTER BET

“Conventional gobar gas plants have a single digester and produce biogas containing 55-65 per cent of methane and 45-35 per cent of carbon dioxide. But the Nisargruna plants are biphasic (aerobic followed by anaerobic phase) and produce biogas containing 70-80 per cent of methane and only 30-20 per cent of carbon dioxide,” he says.
More the methane produced, the better is the fuel value. One tonne of biodegradable waste contains only 22-24 per cent of solid matter; the rest is water. And 30 per cent of municipal waste is biodegradable waste. So with one tonne of biodegradable waste (containing 220-240 kg of solid material) it will be possible to produce 25-30 kg of methane, about 150 kg of carbon dioxide and 50-60 kg of organic manure. The methane enriched biogas can be used directly for heating (instead of LPG) or for generating electricity. Dr. Kale underlines the higher levels of efficiency when it is used directly for heating and strongly recommends it.

BEST USAGE

“One metre cube of biogas has 3,500 kilo calories of heat. When this is used directly, and the efficiency of the heater is 70 per cent, about 2,400 Kcal are effectively used. But one metre cube of biogas can produce only 1.5 to 1.8 units of electricity, accounting only for 1,200 to 1,400 Kcal,” he says. “It is two times more efficient to use methane for heating than for generating electricity. It may be used for electricity generation only where thermal use is not possible.” Constructing a one tonne waste plant will cost Rs.15 lakh and it can be installed in two months. “If a plant runs at full efficiency and if you claim carbon credit, the payback period is two years,” Dr. Kale explains.

HAZARDOUS WASTE

The best part of the technology is its ability to generate resource even from hazardous biological sludge. Waste from textile, food and chemical plants contain harmful chemicals. When the waste is treated, the biological sludge too turns hazardous as organisms absorb harmful chemicals. “The volume of hazardous solids can be reduced by 90 per cent,” he stresses. “There are seven such plants already in operation.” The first to come up was in 2010 in Baddi in Himachal Pradesh at Auro Textiles belonging to the Vardhman Group. He rattles off the details of one plant after another, and it becomes difficult to understand why this technology has not been adopted in a much bigger way across the country. “The concept of processing biodegradable waste is more talked about but urban local bodies are not keen to do it. Nisargruna technology offers a decentralized way of reducing the waste reaching dumping yards,” he says. “The citizens on their part must segregate the waste resources and urban local bodies must make provision to collect these waste resources in a segregated manner. It needs a huge change in perception by the society.” So what makes Nisargruna biogas plants so very efficient? To start with, unlike a gobar gas plant, the Nisargruna plant has two digesters — aerobic and anaerobic. Aerobic digester has nine species of Bacillus required for breaking down waste resources.

The waste is first pulverised in a mixer before it enters the aerobic digester, where it remains for 3 to 4 days. “The smaller clumps tend to aggregate to form lumps [despite pulverisation]. These lumps of waste are attacked by aerobic bacteria. Air and hot water (using solar panels) at 70 degree C are added. “Hot water is added to accelerate the digestion process,” Dr. Kale notes. Though the temperature of the waste after adding hot water is 32 degree C to 35 degree C in winter and 42 degree C to 44 degree C in summer, the bacteria survive as they are thermophilic. “They can function in mesophilic condition as well,” he clarifies. The pulverised water-mixed waste is passed through many compartments so that the bacteria have a better chance to degrade it. What flows out of the aerobic digester to anaerobic digester is almost liquefied homogenous slurry with a reduced pH of 5-5.5. The solid content in the slurry has been reduced from 23 per cent to 10 per cent. “The solid is converted into organic acids and carbon dioxide,” Dr. Kale explains. Methane bacteria are predominant in the anaerobic digester. As a rule, methane bacteria are slow in their actions, and hence it takes about 15 days for the waste to be degraded in the anaerobic digester. “But it has been reduced from 40 days [in the case of gobar gas] to 19 days,” he points out. “This is due to the initial aerobic phase.” All that is left of the waste is methane, carbon dioxide and manure — a rich resource extracted from it.

WEBSITE UPDATES ON SPACE RADIATION HAZARDS

Scientists have developed the first on-line system for predicting and forecasting the radiation environment in near-Earth, lunar and Martian space. Astrophysicists from the University of New Hampshire’s Space Science Center (SSC) created the new near real-time tool that will provide critical information as preparations are made for potential future manned missions to the Moon and Mars. “If we send human beings back to the Moon, and especially if we’re able to go to Mars, it will be critical to have a system like this in place to protect astronauts from radiation hazards,” said researcher Nathan Schwadron. Known as PREDICCS, the web-based tool for the first time integrates numerical models of space radiation, a host of real-time measurements being made by satellites currently in space, and “propagation codes” that can accurately project radiation levels out as far as Mars. The tool was made possible through NASA’s Living With A Star (LWS) Targeted Research and Technology programme.

ON HOURLY BASIS

The website provides updates of the radiation environment on an hourly basis and archives the data weekly, monthly, and yearly. This historical record provides a clear picture of when a safe radiation dose limit is reached for skin or blood-forming organs, for example.

MANAGEMENT OF RICE BLAST DISEASE

Rice blast is a fungal infestation known to occur in all the rice growing areas of the county. The disease attacks all the parts of the crop growing above the soil. It is broadly classified into three types, leaf, collar and neck blasts. Initially elliptical or spindle shaped lesions occurs with brown borders and grey canters. Under favourable conditions, lesions enlarge and coalesce eventually killing the leaves. Leaf blast usually increases early in the season and then declines later as leaves become less susceptible.

BLACK COLOUR

Collar blast occurs when the pathogen infects the collar that can ultimately kill the entire leaf blade. The pathogen also infects the node of the stem known as node blast that turns blackish and breaks easily. Neck blast occurs when the pathogen infects the neck of the panicle. The infected neck is girdled by a greyish brown lesion and the panicle falls over if the infection is severe. If neck blast occurs before the milk stage (rice forming stage), the entire panicle may die prematurely, leaving it white and completely unfilled. Later infections may cause incomplete grain filling and poor milling quality. Varietal resistant to blast is the most practical and economical approach for management. The most common resistant varieties are Aditya, CSR27, IR64, KRH2, Krishna, Hamsa, Naina, Pusa sugandha3, Rasi, Vasumati, PA6129, DRRH2, Dhan80, PR113, Swati, Narendra, Sumati, Swarnadhan, Triguna, Tulasi, IR-36 etc.

DISEASE RESISTANT

Use disease free seeds. Apply recommended dosage of nitrogen application in 3 to 4 splits and avoid final application in infested plots. Burn previous crop residues if the crop is found infested. Early sowing helps prevent this infestation spread from neighbouring fields. Avoid water stagnation. Treat seeds with Pseudomonas fluorescence 10g/lit of water for 30 min, dip the seedlings in Pseudomonas fluorescence 5gm/lit for 20 minutes before transplanting. Foliar spray of the Pseudomonas fluorescence 5gm/lit can be done at an interval of 15-20 days after transplanting.

SCIENTIST DEVELOPED A SUPERHERO MICE

Scientists of the City University of New York in month of October had genetically engineered mice that have up to 500 times more of nose cells to detect explosives and TNT-like chemicals, using the Genetically Modified technology. The mice are named as ‘super-hero’ sniffer mice and have the ability to smell out land-mines and explosives. The mice can be used by armed forces and can be deployed in future, to countries affected by war for rapidly sniffing out of landmines. The project was funded by the US government’s health research arm.

Using of rats and mice is not common phenomenon as it is evident from the fact that a Belgian charity already uses giant African rats to sniff out TNT and has deployed them in Mozambique and Tanzania and on the Thai-Burmese border. While in this research project mice was used because they are cheaper to manage and house and easier to breed.

BCG: A VACCINE FOR MORE THAN JUST TB

In the early years of the last century, the director of a newly-established branch of the famed Institut Pasteur in the northern French city of Lille, Albert Calmette, and his colleague, Camille Guérin, set out to create a vaccine against tuberculosis. In humans, the disease is caused by the bacterium, Mycobacterium tuberculosis . In their quest for a vaccine, Calmette and Guérin worked tirelessly to weaken a related strain found in cattle, Mycobacterium bovis. The idea was that the live but thoroughly weakened microbe would, when administered to people, produce immunity against the TB-causing germ. The vaccine strain they created, ‘bacille Calmette-Guérin’ (BCG), was first given to a newborn infant in July 1921. Even today, it is the only vaccine available against TB. The BCG vaccine is no longer routinely given to children in rich countries where chances of catching the disease are low. However, the vaccine is still widely used in developing countries where the disease is rampant. The World Health Organisation estimates that 100 million children receive it each year. The vaccine provides limited protection against tuberculosis. It does not stop the disease-causing bacterium from establishing an infection, but can help prevent severe forms of TB in infants and young children. It does not, however, provide cover against the disease becoming active in adolescents and adults. Curiously, the protective effects of the vaccine appear to go beyond tuberculosis. When, for instance, the vaccine was introduced in a northern Swedish province in 1927, a physician noticed that those who received it at birth had a death rate only about one-third of that among unvaccinated children.

Controlled trials among children and teenagers in the U.S. and U.K. during the 1940s and 1950s too found that BCG reduced non-accidental deaths from causes other than TB by 25 per cent, noted Peter Aaby and Christine Stabell Benn of the Statens Serum Institut in Denmark in a commentary published in the journal Proceedings of the National Academy of Sciences (PNAS). Trials carried out in West Africa a few years back found that the BCG vaccine reduced deaths among low-birth-weight newborns by more than 40 per cent, mainly by preventing sepsis and respiratory infections, they pointed out. Research carried out by a team of Dutch scientists and published recently in PNAS explains why BCG could be having such a broad protective effect. Vaccines are known to stimulate the adaptive arm of the immune system, thereby establishing a ‘memory’ of a specific invader to be recognised and repulsed. BCG, on the other hand, was working on the evolutionarily more ancient innate immune system that is triggered by molecules that commonly marked out a pathogen, such as components of their cell wall. “The general perception in immunology is that innate immunity, as opposed to adaptive immunity, is static and does not adapt to an enhanced functional state,” observed Mihai Netea of Radboud University Nijmegen Medical Centre and his colleagues in their PNAS paper. BCG was inducing “trained immunity” by reprogramming cells known as monocytes that formed part of innate immune system. When BCG was administered, the live bacteria in the vaccine would be devoured by the monocytes. Inside the monocytes, muramyl dipeptide, a constituent of the bacterial cell wall, was then able to latch on to a receptor known as NOD2. That, in turn, set off a chain of events that led to molecular tags being attached to a protein, called a histone, around which DNA is wrapped.

Such reprogramming allowed certain genes to be more active and thereby produce more protein. Those monocytes were then capable of an enhanced response when confronted with a range of different pathogens, churning out chemicals known as cytokines that mobilised the immune system to fight off an invading microbe. The Dutch scientists showed that monocytes taken from volunteers who received BCG showed a considerably increased cytokine response to unrelated pathogens, such as the bacteria Staphylococcus aureus and the yeast Candida albicans. BCG also ensured significantly better survival when mice from a strain that lacked cells of the adaptive immune system were exposed to lethal doses of C. albicans . The work of these scientists very likely explained why BCG has been consistently observed to reduce death and sickness to a far greater extent than could be explained by the prevention of TB, remarked Dr. Aaby and Dr. Benn in their commentary. Randomised trials had shown that after BCG and measles vaccination, the contribution of nonspecific effects to overall health far outweighed the importance of the specific protection provided by these vaccines. With two trials of early BCG vaccination planned in Denmark and Australia, perhaps the vaccine would be reintroduced in high-income countries for its training effects rather than for protection against TB. “Disentangling the mechanisms of the nonspecific effects may establish a new paradigm in immunity with a stronger emphasis on training and innate immunity,” they said. Could the elderly too, with waning immune function that makes them vulnerable to a variety of infectious diseases, benefit from BCG boosting their innate immunity? “Absolutely yes, I think that this could be a major potential treatment and we are working on that,” said Dr. Netea in an email.

SOLAR PARTICLES LIKELY SOURCE OF LUNAR WATER

Charged particles from the sun or solar winds, bombarding the lunar surface, could explain the presence of water locked inside its soil, new research says. Over the past five years, spacecraft observations and new lab measurements of Apollo lunar samples have overturned the long-held belief that the moon is bone-dry. In 2009, NASA’s Lunar Crater Observation and Sensing satellite, known as LCROSS, slammed into a permanently shadowed lunar crater and ejected a plume of material that was surprisingly rich in water ice, the journal Nature Geoscience reports. Water and related compounds have also been detected in the lunar regolith, or the layer of fine powder and rock fragments that coats the lunar surface. But the origin of lunar surface water has remained unclear, according to a Michigan University statement. The findings from University of Michigan researcher Youxue Zhang and colleagues from the University of Tennessee (UT) and the California Institute of Technology support solar-wind production of water ice on the moon.

“We found that the ‘water’ component, the hydroxyl, in the lunar regolith is mostly from solar wind implantation of protons, which locally combined with oxygen to form hydroxyls that moved into the interior of glasses by impact melting,” said Zhang, professor of geological sciences. “Lunar regolith is everywhere on the lunar surface, and glasses make up about half of lunar regolith. So our work shows that the ‘water’ component, the hydroxyl, is widespread in lunar materials, although not in the form of ice or liquid water that can easily be used in a future manned lunar base.” The findings imply that ice inside permanently shadowed polar craters on the moon, sometimes called cold traps, could contain hydrogen atoms ultimately derived from the solar wind, the researchers report. The researchers analysed individual grains from Apollo 11, Apollo 16 and Apollo 17 missions .

SPOTTING DISEASES FROM BONE SAMPLES

A new technology can analyse millions of gene sequences in a matter of seconds to identify diseases accurately, according to a new breakthrough.

Terry Brown, working with Charlotte Roberts, both professors at Durham University (UK), used a next-gen sequencing approach, including hybridization capture technology, to identify tuberculosis (TB) genes in a 19th century female skeleton found in a crypt in Leeds. Roberts said: “We’re really pleased with the results of this study and that the technology works. It will save a lot of time in the future. “We now hope to publish more of the huge amounts of data we have acquired from the sequencing.” Their study is part of wider research into the identification of strains of TB in skeletons dating from 100 AD to the late 19th century. It’s hoped that understanding how the disease has evolved over time will help improve treatments and vaccines. After HIV it kills more people than any other infectious disease, according to a Durham statement. Certain strains of TB affect the sufferer’s bones, especially in the spine. The marks made by the disease remain evident on the bones long after the person’s death. It’s this evidence that Roberts used to find suitable skeletons to screen for tuberculosis genes. She sourced 500 skeletons from across Europe that showed evidence of TB dating from the Roman period to the 19th century. Bone samples from these skeletons were screened for TB DNA, and of those 100 were chosen for this particular study. Roberts explained: “So many skeletons were needed as it’s very hard to tell if any DNA will have survived in the bones. You don’t really know if there will be any present until you start screening and in the past that has been a lengthy process.” Brown and team then searched for TB gene sequences. Because it is a bacterial disease the bacteria’s DNA can remain in the bones after death.

CHICKOO MOTH MANAGEMENT IN SAPOTA

Sapota, a native of Mexico, is grown widely in India for its fruit and milky latex which is the source of chicle used to make chewing gum.

Of the several pests infesting the tree, the sapota leaf webber ( Nephopteryx eugraphella ) commonly called as chickoo moth is a major one.

DAMAGE SYMPTOMS

As the name indicates, the caterpillars of the moth spin web on the leaves and also feed on tender leaves and fruits throughout the year. Presence of dry leaf clusters and dark brown patches on the leaves are clear symptoms of the infestation and can be easily spotted from a long distance. The infestation leads to withering and drying of tree branches. The pest activity increases with appearance of new shoots and buds. A wide range of sapota varieties are susceptible to this pest. The moth is grey in colour measuring around one centimetre in length. It lays eggs on leaves and buds of young shoots. Around 350 eggs are laid by a single female. The incubation period is around one week and after hatching the pink coloured caterpillars start feeding on green leaves by scrapping the chlorophyll content leaving behind a fine network of veins. They also bore inside the flower buds and tender fruits which wither away and drop down. The larvae can damage many fruit buds during its developmental period which lasts from 13 to 60 days according to environmental conditions. Pupal stage is completed in 8 to 29 days. There are eight to nine generations of this pest in a year.

MANAGEMENT

• Remove and destroy all the webbed leaves, shoots, buds and fruits along with larvae.

• Crowded and crossing branches should be pruned.

• Plant resistant varieties such as PKM 1 Sapota

• Erect light trap at one per hectare to monitor the activity of chickoo moth

• Spray two rounds of carbaryl 0.1 per cent, chlorpyriphos 0.05 per cent or quinalphos 0.05 per cent at 20 days interval after new shoot formation and fruit harvest.

SCIENTIST DISCOVERED SOURCE OF WATER ON MOON

Scientists in third week of October have discovered that the most likely source of water on Moon is the constant stream of charged particles from the Sun known as the solar wind. The findings came by researchers from the University of Michigan who imply that ice inside permanently shadowed polar craters on the Moon, sometimes called cold traps, could contain hydrogen atoms ultimately derived from the solar wind.

Also, The Theoretical models of lunar water stability dating to the late 1970s suggest that hydrogen ions (protons) from the solar wind can combine with oxygen on the Moon’s surface to form water and related compounds called hydroxyls, which consist of one atom of hydrogen and one of oxygen and are known as OH. The researchers have found that the ‘water’ component, the hydroxyl, in the lunar regolith is mostly from solar wind implantation of protons, which locally combined with oxygen to form hydroxyls that moved into the interior of glasses by impact melting. With this research it is also clear that water likely exists on Mercury and on asteroids such as Vesta or Eros further within our solar system. The study findings are published in the journal ‘Nature Geoscience’.

WHY AND HOW IS WATER TRANSPARENT?

Light is a form of an electromagnetic energy with a wide range of wavelengths. However, the range that a human eye can ‘see’ is very tiny segment, ranging from about 400 nanometres to about 800 nanometres. This narrow range of wavelengths which a human eye is sensible to, is known as ‘the visible region’ of the electromagnetic radiation. Two of the most important interactions a material can engage with radiation are absorption and scattering. When light is incident on an object, the portion that is neither absorbed nor is scattered is, usually, transmitted through it to the other side. If a material absorbs any part of the visible region then the material appears coloured to us. The colour, an object looks, is called ‘complementary’ to the portion of light absorbed.

If a material absorbs all the visible range of light, then it ‘looks’ black to us because there is hardly any visible light left from the object to reach our eyes. If a material does not absorb any part of the visible range of light, then the object either appears colourlessly transparent, when the light is transmitted, or white, when scattered. Water has H{-2}O molecules that do not have the kind of electrons which absorb any portion of the visible range (but have electrons that absorb only in the invisible ultraviolet range) of light and their size is less than 4 angstroms (tenth of a nanometre) with an average intermolecular space of less than 10 angstroms. That is why water appears transparent. Several other liquids, such as benzene, alcohol, chloroform, coconut oil, etc also look transparent for this reason. Even when the size of the non-absorbing constituents is less or more than the wavelength but if the inter space among them or the size of edges made of them is somehow comparable to the wavelength of the visible radiation, then the object just looks white because much of the unabsorbed light is scattered. A piece of chalk, ground glass, smoke, milk, etc, look white for of this reason.

HIGH-ENERGY PHYSICS IN TOTO WILL MAKE A SWITCH

Till now encouragement or compulsion to publish papers in open-access journals came from universities or funding agencies like the U.S. National Institutes of Health (NIH), and Research Councils UK (a nodal body for seven government-funded grant agencies), and was restricted to relatively fewer countries. But the switch to be made in high-energy physics has the support and backup — both in principle and funding — from many countries involved in particle physics research. High-energy physics has been spearheading Open Access for a long time. Pre-prints are freely available on the Net. “Today about 90 per cent of HEP pre-prints are available in repositories,” notes the executive summary of the Report of the SCOAP3 Working Party. Though these repositories have become the “lifeblood of HEP scientific information exchange” there is a big difference — the papers posted in the repositories are only the manuscripts submitted to the journals and not the peer-reviewed papers that appear in journals.

The change to the OA model will amount to about 10 million euros a year. The executive summary notes that annual list-price of a single journal can be as high as 10,000 Euros. “For 500 institutes worldwide… this represents an annual expenditure of 5 million Euros.” The Sponsoring Consortium for Open Access Publishing in Particle Physics (SCOAP3) has “negotiated contracts with 12 journals that would make 90 per cent of high-energy physics papers published from 2014 onwards free to read,” Salvatore Mele, head of open access at CERN, was quoted as saying in Nature. SCOAP3 Open Access Initiative was launched at CERN on October 1. “It is gratifying to see how the model of international collaboration in particle physics has been applied to addressing the important societal issue of open access to scientific information,” Rolf Heuer, CERN Director General was quoted as saying in a CERN press release.

ITCHING SENSATION IN OUR MOUTH WHEN WE EAT TOO MUCH OF PINEAPPLE

Pineapple is a tropical plant with botanical name, Ananas comosus , belonging to the Bromeliaceaefamily. It is one of the very popular edible materials consumed in many formats. It is a rich dietary source of vitamin C, vitamin B complex, calcium, manganese, magnesium, phosphorous, potassium, etc among others.

Pineapple, botanically, is not a single fruit berry. It is a collection of individual fruits (each fruit, marked on the surface by the near-hexagonal demarcation) with their stalks impregnated collectively, with boundaries gradually becoming undefined, into the tip that appears asthe grand stalk. There are two reasons with varied degrees why consumption of good quantities of pineapple make our mouth and the tongue itching. Pineapple contains a proteolytic (protein hydrolyzing) enzyme, called, bromelain. It is mostly present in the inedible stalk (the central axis part of the fruit or the grand stalk mentioned above). When we have eaten the pineapple, this bromelain temporarily stays on the tongue and interiors of the mouth and starts attacking the proteinous muscle parts of the tongue and the mouth while sensitizing the nerve endings there. These neurological signals, when transmitted to the brain, make us feel the pricking and itching sensation. The other minor but cognizably effective reason is due to the presence of nano-sized spiny fibrils that are either left there or mixed with the pulp of the pineapple when we have cut it. These fibrils are like the eyelashes of the groves (individual fruits) on the pineapple. They are cuticle-like materials composed of glycoproteinous chitin, wax and collagen. While we eat the pineapple, these microscopic fibrils also enter the mouth and find their way into the interiors of mouth parts causing their pricks before they are slowly washed away by the saliva.

FARMERS PARTICIPATORY PROGRAMME STEMS COCONUT TREE INFESTATION

Bud rot is a fatal fungal disease affecting coconut trees. Young trees are more susceptible particularly during the monsoon. With this infestation, the spear leaf becomes pale and breaks at the base and hangs down. The tender leaf base and soft tissues of the crown rot into a slimy mass of decayed material emitting foul smell. The rotting progresses downwards, affecting and killing the entire tree.

Lack of awareness about the disease and its management practice is also leading to a disease spread. Individual prevention adoption by few farmers here and there is ineffective as coconut is cultivated almost throughout Kannur region in Kerala.

SEVERE SPREAD

The spread of the disease is so severe that 14,350 hectares of coconut growing area is infected by this lethal menace. “Bud rot is a serious problem throughout Kannur district and prophylactic chemical treatment proves to be effective. “During 2007-08 we have successfully demonstrated this technology in Ayyankunnu Panchayath. However the disease was rampant in other agro- ecological zones also and it was found necessary as per the demands of farmers to conduct demonstrations in different regions to curb the spread of the disease,” says Dr.Abdul Kareem, Programme Coordinator, Kerala agricultural University, Kahirangad. “We planned and implemented a frontline demonstration (FLD) of perforated plastic sachets containing 2-3 grams Mancozeb, two sachets per palm tied on the inner side of the spear leaf, spraying of bordeaux mixture on affected portion as well as neighbouring trees, removal and destruction of affected portions and application of bordeaux paste for combating the problem for four consecutive years (from 2007-8 to 2010-11),” he explains. For this demonstration, two regions Koralai and Kolacherry, were selected; farmers were identified, group discussions, trainings and method demonstrations were done. A total of 22 hectares, 4,000 trees, and 50 farmers were covered under this.

CONTROL MEASURES

The Krishi Vigyan Kendra at Kannur areas has adopted farmer participatory extension approach, named as Compact Area Group Approach, which is now popularly known by its acronym, CAGA to control bud rot disease. CAGA promoted and sustained group action in a contiguous area for durable adoption of control measures by solving several hurdles. Preparation of plastic sachets manually is a cumbersome process since a lot of holes have to be made on the sachets. To overcome this problem a small machine has been fabricated to puncture holes continuously on plastic tubes of 3-inch width. This tube is cut into required length and filled with two gms of mancozeb and tied at ends. Cost of production of this sachet works out to only Rs. 2.50 per sachet. The Department of agriculture helped arrangement of climbers in a few panchayaths at a cost of Rs. 10 per tree and in the remaining areas KVK helped farmers to arrange for climbers by themselves. Coconut tree climbers are the only persons who see and feel the extent and magnitude of the disease incidence in the tree as they climb. Decision-making on their part was very important for application of control measures in an effective manner.

TRAINING THE CLIMBERS

“Therefore the climbers were made conversant with all aspects of the technology like understanding magnitude of disease incidence, handling of sachets, placement and tying method of sachets, importance of cleaning methods, preparation of mixture and paste, areas and method to apply it etc,” says Dr. Kareem. Integrated disease management focuses not only on application of chemical but also on maintaining health of plant. The health of the plant is mainly attributed to the proper nutrition for the plant. During farmers’ meetings conducted in the CAGA approach, a lacuna in application of organic matter came up. Recommended dosage of organic manure (25kg/ tree) cost more than Rs. 50 and farmers were not applying the manure. In this context scientists introduced a very cost effective technology of insitu green manuring using cowpea seeds.

ORGANIC MANURE

Only 100 gm of cowpea seeds are required for one coconut basin to be sown at the onset of monsoon to produce 25 kg of biomass within few months.
Thus cost of organic manure came down to Rs. 5 from Rs. 50. Application of sachets, when clubbed with harvest before monsoon season, reduced the cost of application. Coconut growers throughout the district were made aware about the bud rot management practices through wide publicity.

Adoption level of farmers increased to 100 per cent due to the visualised effect of control measures recording very positive results.

CONTROL OF SIGATOKA DISEASE OF BANANA

Sigatoka leaf spot is a serious disease of banana that destroys large areas of plantations resulting in severe reduction in fruit yield.

The commercial cultivars nendran and robusta are highly susceptible to this infestation whereas in rasthali and palayankodan varieties the disease severity is less. This infestation is caused by a fungus and was first recorded in the Sigatoka valley of Fiji. Economic losses of 50-100 per cent have been incurred due to the incidence of this disease.

DARK BROWN SPOTS

Symptoms of Sigatoka disease first appear as small dark brown spots or lines on the underside of third or fourth opened leaf. The spots become sunken surrounded by a yellow halo. Eventually these spots or streaks expand and become brown or black and make a characteristic black patch on the leaves. The infection gives a scorched appearance to the foliage.
Infection on younger leaves is more severe causing them to dry up more quickly. Appreciable fruit loss occurs as there is drastic reduction of leaf surface area for photosynthesis.
Infected banana plants produce fruits of inferior quality as the banana fingers produced do not develop properly and remain small and thin.

MONSOON SEASON

Spores of the fungal pathogen form in abundance during tropical and sub tropical summers along with intermittent rainfall especially if there is a film of water on the leaves. The principal means of spread is through rain but later with the progressive development, spores are also discharged through air currents. Spotting of leaves starts to increase during June, July, peaks in October-November and remains at a high level through December. Management mainly involves chemical control using fungicides like copper oxychloride, mancozeb, chlorothalonil or carbendazim at the prescribed dosage. Fungicide spraying on the foliage and pseudostem should be commenced with the initial appearance and repeated at two weeks’ interval. Use of the different fungicides in rotation will reduce the risk of resistance development in the pathogen to the systemic chemicals.

METHODS TO MEASURE, MANIPULATE QUANTUM SYSTEMS

Serge Haroche and David Wineland have opened the door to a new era of experimentation with quantum physics by demonstrating the direct observation of individual quantum systems without destroying them.

Through their ingenious laboratory methods they have managed to measure and control very fragile quantum states, enabling their field of research to take the very first steps towards building a new type of super fast computer, based on quantum physics. These methods have also led to the construction of extremely precise clocks that could become the future basis for a new standard of time, with more than hundred-fold greater precision than present-day caesium clocks. For single particles of light or matter, the laws of classical physics cease to apply and quantum physics takes over. But single particles are not easily isolated from their surrounding environment and they lose their mysterious quantum properties as soon as they interact with the outside world. Both Laureates work in the field of quantum optics studying the fundamental interaction between light and matter. In David Wineland’s laboratory in Boulder, Colorado, electrically charged atoms or ions are kept inside a trap by surrounding them with electric fields. One of the secrets behind Wineland’s breakthrough is the mastery of the art of using laser beams and creating laser pulses. A laser is used to put the ion in its lowest energy state and thus enabling the study of quantum phenomena with the trapped ion. A carefully tuned laser pulse can be used to put the ion in a superposition state, which is a simultaneous existence of two distinctly different states. For instance, the quantum superposition of the ion’s energy states can be studied by using the laser pulse to nudge the ion halfway between the high- and low-energy levels.

CONTROLLING SINGLE PHOTONS

Serge Haroche and his research group employ a different method to reveal the mysteries of the quantum world. In their laboratory in Paris microwave photons bounce back and forth inside a small cavity between two mirrors, about three centimetres apart. The mirrors are made of superconducting material and are cooled to a temperature just above absolute zero. These superconducting mirrors are so reflective that a single photon can bounce back and forth inside the cavity for almost a tenth of a second before it is lost or absorbed. During its long life time, many quantum manipulations can be performed with the trapped photon. Haroche uses specially prepared atoms, so-called Rydberg atoms to both control and measure the microwave photon in the cavity. A Rydberg atom has a radius of about 125 nanometres which is roughly 1,000 times larger than typical atoms. The Rydberg atoms are sent into the cavity one by one at a carefully chosen speed, so that the interaction with the microwave photon occurs in a well-controlled manner.

The Rydberg atom traverses and exits the cavity, leaving the microwave photon behind. But the interaction between the photon and the atom creates a change in the phase of quantum state of the atom: if you think of the atom’s quantum state as a wave, the peaks and the dips of the wave become shifted. This phase shift can be measured when the atom exits the cavity, thereby revealing the presence or absence of a photon inside the cavity. With no photon there is no phase shift. Haroche can thus measure a single photon without destroying it. Physics in the quantum world has some inherent uncertainty or randomness to it. One example of this contrary behaviour is superposition, where a quantum particle can be in several different states simultaneously.

Why do we never become aware of these strange facets of our world? Why can we not observe a superposition of quantum marble in our every-day life? The Austrian physicist and Nobel Laureate (Physics 1933) Erwin Schrödinger battled with this question. Like many other pioneers of quantum theory, he struggled to understand and interpret its implications. As late as 1952, he wrote: “We never experiment with just one electron or atom or (small) molecule. In thought-experiments we sometimes assume that we do; this invariably entails ridiculous consequences...”

In order to illustrate the absurd consequences of moving between the micro-world of quantum physics and our every-day macro-world, Erwin Schrödinger described a thought experiment with a cat: Schrödinger’s cat is completely isolated from the outside world inside a box. The cat must be in a superposition state of being both dead and alive. The box also contains a bottle of deadly cyanide which is released only after the decay of some radioactive atom, also inside the box. The radioactive decay is governed by the laws of quantum mechanics, according to which the radioactive material is in a superposition state of both having decayed and not yet decayed. Therefore the cat must also be in a superposition state of being both dead and alive. Now, if you peek inside the box, you risk killing the cat because the quantum superposition is so sensitive to interaction with the environment that the slightest attempt to observe the cat would immediately ‘collapse’ the ‘cat-state’ to one of the two possible outcomes — dead or alive.Instead of Schrödinger’s cat, Haroche and Wineland trap quantum particles and put them in cat-like superposition states. These quantum objects are not really macroscopic as a cat, but they are still quite large by quantum standards. Inside Haroche’s cavity microwave photons are put in cat-like states with opposite phases at the same time, like a stopwatch with a needle that spins both clockwise and counterclockwise simultaneously. The microwave field inside the cavity is then probed with Rydberg atoms. The result is another unintelligible quantum effect called entanglement. Entanglement has also been described by Erwin Schrödinger and can occur between two or more quantum particles that have no direct contact but still can read and affect the properties of each other. Entanglement of the microwave field and Rydberg atoms allowed Haroche to map the life and death of the cat-like state inside his cavity, following it step by step, atom by atom, as it underwent a transition from the quantum superposition of states to a well defined state of classical physics.

COMPUTER REVOLUTION

A possible application of ion traps that many scientists dream of is the quantum computer. In present-day classical computers the smallest unit of information is a bit that takes the value of either 1 or 0. In a quantum computer, however, the basic unit of information — a quantum bit or qubit — can be 1 and 0 at the same time. Two quantum bits can simultaneously take on four values — 00, 01, 10 and 11 — and each additional qubit doubles the amount of possible states. For n quantum bits there are 2{+n} possible states, and a quantum computer of only 300 qubits could hold 2{+3}{+0}{+0}values simultaneously. Wineland’s group was the first in the world to demonstrate a quantum operation with two quantum bits. Since control operations have already been achieved with a few qubits, there is no reason to believe that it should not be possible to achieve such operations with many more qubits. However, to build such a quantum computer one has to satisfy two opposing requirements: the qubits need to be adequately isolated from their environment in order not to destroy their quantum properties, yet they must also be able to communicate with the outside world in order to pass on the results of their calculations. David Wineland and his team of researchers have also used ions in a trap to build a clock that is a hundred times more precise than the caesium-based atomic clocks which are currently the standard for our measurement of time. Time is kept by setting, or synchronizing all clocks against one standard. Caesium clocks operate in the microwave range whereas Wineland’s ion clocks use visible light — hence their name: optical clocks.

OPTICAL CLOCKS

An optical clock can consist of just one ion or two ions in a trap. With two ions, one is used as the clock and the other is used to read the clock without destroying its state, or causing it to miss a tick. The precision of an optical clock is better than one part in 10{+1}{+7}— if one had started to measure time at the beginning of the universe in the Big Bang about 14 billion years ago, the optical clock would only have been off by about five seconds today. With such precision, some extremely subtle and beautiful phenomena of nature have been observed, such as changes in the flow of time, or minute variations of gravity, the fabric of space-time. According to Einstein’s theory of relativity, time is affected by motion and gravity. The higher the speed and the stronger the gravity, the slower the passage of time. We may not be aware of these effects, but they have in fact become part of our everyday life. When we navigate with the GPS we rely on time signals from satellites with clocks that are routinely calibrated, because gravity is somewhat weaker several hundred kilometres altitude. With an optical clock it is possible to measure a difference in the passage of time when the clock’s speed is changed by less than 10 metres per second, or when gravity is altered as a consequence of a difference in height of only 30 centimetres.

Unlocking secrets of cauliflower’s geometry

The laws that govern how intricate surface patterns, such as those found in the cauliflower, develop over time have been described, for the first time, by a group of European researchers.

No age restriction, says vaccination study

A study suggests that the additional children’s lives saved by removing the age restrictions for rotavirus vaccination would be much greater than any extra deaths from vaccine-associated complications.

New water-proof colour from butterfly study

University of Pennsylvania researchers studying butterflies have found a way to generate colour that can repel water based on a trait of butterfly wings: super-hydrophobicity.

Nanoparticle cancer therapy safe in dogs

Scientists at the University of Missouri have demonstrated that a new form of prostate cancer treatment that uses radioactive gold nanoparticles is safe to use in dogs. It has a chance of being used in humans.

Lethal virus disease prevented in monkeys

By using monoclonal antibodies, a new ebola virus study resulting from a widespread scientific collaboration has shown promising preliminary results, preventing disease in infected nonhuman primates.

Space launch system’s arm ready

System installation and integration of a test umbilical arm was recently completed at NASA’s Kennedy Space Center in Florida.

Coral migration and evolution of marine life

A new study in Molecular Ecology elucidates the historical patterns of deep-sea coral migration and gene flow, coincident with oceanic circulation patterns and events. Protecting corals requires this knowledge.

Human brains outpace chimp brains in womb

Humans’ superior brain size in comparison to chimpanzees’ traces back to the womb says a study in Current Biology , the first to track and compare brain growth in chimpanzee and human fetuses.

Light shed on Sun’s explosive ejections

In a paper in Nature Physics , an international team of scientists, explains the mysterious physical mechanisms underlying the origin of Sun’s coronary mass ejections based on state-of-the-art computer simulations.

Exercise does body and mind good

Exercise is not just good for physical health — research shows that daily physical activity can also boost our mental health.

Bat study sheds new light on evolution

Brain size relative to body size has been used for long as a measure of intelligence. The evolutionary history of bats reveals they decreased body size faster than brain size, leading to an increase in intelligence.

Active region on Sun emits another flare

The sun emitted a significant solar flare on October 22. The flare came from an active region on the left side of the sun that has been numbered AR 1598, which has already been the source of a number of weaker flares.

Fingers do the talking

People can use their fingers with a new touch-activated system that projects onto surfaces and allows users to interact with their environment and each other.

Reducing cold-induced sweetening in potato

Preventing activity of a key enzyme which causes changes in potato sugars at low temperatures could boost quality by putting an end to cold-induced sweetening, say U.S. Department of Agriculture scientists.

Metabolic syndrome link to impaired brain

A new study in Pediatrics reveals that metabolic syndrome (MetS) is associated with cognitive and brain impairments in adolescents and needs to be taken into account when considering early treatment of childhood obesity.

Primate study adds to evidence of BPA harm

A Washington State University researcher has found new evidence that the plastic additive BPA can disrupt women’s reproductive systems, causing miscarriages and birth defects.

New gene for better bug-resistant plants

Acyl sugars, not found in cultivated tomatoes, play a key role in allowing wild tomatoes to fend off bugs. New research at Michigan State University identifies the first gene that helps produce acyl sugars.

Adequate sleep cuts appetite, excess fat

Adequate sleep is an important part of a weight loss plan and should be added to the recommended mix of diet and exercise, states CMAJ ( Canadian Medical Association Journal ). Less sleep means more appetite.

Bee behaviour evolved due to genetic ‘remix’

Worker bees have become a highly skilled work force because the genes that determine their behaviour are shuffled frequently, helping natural selection to build a better bee, says a York University study.

Viral alliances overcoming plant defences

Researchers have found that viruses will join forces to overcome a plant’s defences and cause more severe infections.

Local wildlife’s role in Central African diet

Animals like antelope and rodents are tricky to catch, but provide protein in places where livestock are scarce. According to a new paper in Animal Frontiers , meat from wild animals is increasingly important in central Africa.

Link between Hawaii’s enigmatic volcanoes

A new Rice University-led study finds that a deep connection about 50 miles underground can explain the enigmatic behaviour — their simultaneous inflation, or bulging upward of Mauna Loa and Kilauea volcanoes.

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