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November 2016 Vol. 19 No. 2 Rs. 5.00 2016 Nobel Prizes in

Editorial: Why should Article 35 12 of the Paris Agreement about .....

India's first Science 34 City turns 20

Lise Meitner – The Mother of 31 Nuclear Fission

Plastic Pollution 28 and Remedial Measures

2016 Nobel Prizes in Science 26

Anal Fistulas— 24 All You Want to Know About

Recent developments 21 in science and technology

36 Editorial Why should Article 12 of the Paris Agreement about climate change not be considered science popularisation? Dr. R. Gopichandran

India communicated with the on the 2nd agenda will be i) Reaching the unreached; ii) Reality this month that she has ratified the Paris Agreement. This is checks on information and capacity building needs seen as a major step forward to help account for the number of specific stakeholder groups so that appropriate of countries needed to set related activities on the move. information can be delivered in a timely manner. India recognises the pervasive nature of challenges posed Awareness can be a robust forerunner to capacity by climate change and expressed her preparedness to join building. (iii) Will it not be useful to create a worldwide efforts. community of practitioners based on their abilities Article 12 of the Agreement states, “Parties shall to assess mitigation and adaption opportunities cooperate in taking measures, as appropriate, to enhance and actually help deliver sustainable solutions? iv) climate change education, training, public awareness, public Information clearing houses with teach and learn participation and public access to information, recognising modules on mitigation and adaption practices are the importance of these steps with respect to enhancing essential elements of enabling access to state of art actions under this Agreement”. The agenda for science and information on a continual basis. technology communication has been accordingly set. A • It is equally important to let people know about efforts major thrust on science popularisation can also be construed undertaken by the Government of India including looking at the need for public awareness and access to funding mechanisms that help access alternatives and information. foster locally relevant and feasible action. I wish to argue that radio and television-based modules This logical framework will only help synergize on the science of the phenomenon of climate change, India- with the efforts of the designated agencies and smother specific aspects regarding nature and scale of impacts, signals, turf boundaries through a common agenda. Technology their manifestation and persistence and the roles individuals communication also assumes comparable pathways. can play in mitigation and adaptation functions are well The Paris Agreement centres on an overarching within the framework of science popularisation. framework of quality of , thereby linking the imperatives • Communicators should not shy away from this of sustainable development and disaster risk reduction. These opportunity to connect with citizens about these are unique integrated windows of opportunity to highlight topics simply saying that there are many other agencies pervasiveness of science and the proximity of its applications designated to carry out these tasks and that there are in daily life. Additionally, economic and livelihood turf-related institutional challenges. Why should I sustainability considerations are intertwined. Insights not take it as an excuse for not wanting to rise up to about open-endedness and methods of science can best be communicate about high-rigour science? embedded in modules that communicate these aspects. I • Genuine concerns about turfs and designated agencies will be happy to understand an alternative perspective. can be overcome by defining the unfinished agenda. Some of the important elements of such an unfinished Email: [email protected] n

Editor : R Gopichandran Vigyan Prasar is not responsible for the statements/opinions expressed and photographs used by the authors in their articles/write-ups published in Associate editor : Rintu Nath “Dream 2047” Production : Manish Mohan Gore and Pradeep Kumar Articles, excerpts from articles published in “Dream 2047” may be freely Expert member : Biman Basu reproduced with due acknowledgement/credit, provided periodicals in Address for Vigyan Prasar, C-24, which they are reproduced are distributed free. correspondence : Qutab Institutional Area, New Delhi-110 016 Published and Printed by Manish Mohan Gore on behalf of Vigyan Prasar, Tel : 011-26967532; Fax : 0120-2404437 C-24, Qutab Institutional Area, New Delhi - 110 016 and Printed at Aravali e-mail : [email protected] Printers & Publishers Pvt. Ltd., W-30, Okhla Industrial Area, Phase-II, website : http://www.vigyanprasar.gov.in New Delhi-110 020 Phone: 011-26388830-32. 35 Dream 2047, November 2016, Vol. 19 No. 2 India’s first Science

City turns 20 Dr Jayanta Sthanapati E-mail: [email protected]

Chief Minister of West Bengal. Facilities available in this complex are (i) Main Auditorium with 2,232 seating capacity, (ii) Mini Auditorium with 393 seating capacity, (iii) Seminar Hall complex comprising 11 halls and a lobby, (iv) 2.5 hectares of uncovered exhibition ground, and (v) parking space for around 500 vehicles.

B. Science Centre Complex

Science City, Kolkata in 1998 1. Space Odyssey Space Odyssey is an enclave where visitors experience a thrilling voyage to the Science City, a landmark of Kolkata help of educative and entertaining exhibits. through exhibits called Space Theatre, in post-independence era for science A Science City is expected to be financially Space Science, Machine, 3D Theatre, communication, is the first and largest of self-sustainable. Spinning platform, Van-de-Graaff generator, its kind in India. Situated on a 20-hectare It was Dr Saroj Ghose, Diector General Mirror Magic, and interactive multimedia plot of land of sprawling greenery, at the of NCSM, who in 1992 had conceptualised kiosk on Solar System. crossing of Eastern Metropolitan Bypass this gigantic science and technology enclave. and J.B.S. Halden Avenue (or Park Circus In 1993, the Calcutta Municipal Corporation (i) Space Theatre connector), it is a constituent unit of the (CMC) gifted more than 12 hectares of land In this 23-metre dome theatre with seating National Council of Science Museums to NCSM for the Science City project. CMC capacity of 360 is suitable for both large- (NCSM), an autonomous body under the further transferred about 8 hectares of land format movies and planetarium shows. Ministry of Culture, Government of India. to NCSM on long-term lease. Science City was a unique gift to the city of The Kolkata Science City Kolkata in the Golden Jubilee Year of Indian primarily consists of two major facilities Independence, dedicated to the people by – the ‘Convention Centre Complex’ and the Shri Inder Kumar Gujral, Prime Minister of ‘Science Centre Complex’. India on 1 July 1997. A Science City is conceptually similar A. Convention Centre Complex to a Science Centre, but is much larger This facility of Science City was completed in dimension. It portrays the growth of in the first phase of the project. It was science and technology and their application inaugurated on 21 December 1996 by Prof in society, for general visitors including Paul J. Crutzen, the 1995 Nobel Laureate in students, families, and tourists, with the Chemistry, in presence of Shri Jyoti Basu, Space Odyssey and Dynamotion Hall in 1997

It is equipped with GSS-Helios Ball planetarium projector manufactured by Goto Optical Mfg. Ltd., Japan and is supported by 150 special effect projectors and Astrovision- 70 large-format movie projection system. The system was imported by Science City Kolkata in 1996 and installed in early 1997.

(ii) 3D Vision Theatre Since human eyes are located side by side, Convention Centre each eye captures a slightly different view of

Dream 2047, November 2016, Vol. 19 No. 2 34 India's first Science City turns 20

yourself, Erase the figure, (ii) Biodiversity Floating mirror, Fun The exhibition was set up in 2010 to mirror, Ghost wall, Giant commemorate the International Year of hall, Half you and half Biodiversity. The process of me, Head on a platter, is explained here with the help of a series of Hole in the chest, Honey exhibits dealing with plant, leaf, internal comb, Horizontal image, structure of leaf, organs responsible for Icosahedron, Infinite absorption of dioxide and release well, Interactive zone, of , role of chloroplasts in making Kaleidoscope, Mirror in chlorophyll, chemical reactions that takes kitchen, Mirror maze, place in the process of photosynthesis, etc. Mirror wall, Octahedron, and dark reactions that occur during Periscope, See your back, photosynthesis are also explained in these Side image, True image, exhibits with interesting illustrations. Further Upside down, Vanishing there are 3D models of a cell, nucleus, Inner view of Space Theatre image, and You and me. nucleolus, lysosomes and mitochondria on display. the same object. These two signals are then processed in the brain to form 3D image of (iii) Butterfly Enclave the object, with the perception of depth. For Several butterflies can be seen in this shooting an image in 3D, two cameras are enclave located on the ground floor of used to capture images of an object from Dynamotion Hall. Here the visitors can see slightly different angles. The captured images the whole life cycle of a butterfly. One can when projected on screen in a theatre and also know interesting facts about laying of viewed through special polaroid spectacles eggs by butterflies on a particular plant. The gives the feeling of watching the movie in eleven life of butterflies exhibited 3D. In 3D theatre of Science City Kolkata, in the enclave are: Angled Custer (Ariadne 3D movies are screened regularly for the ariadne); Blue Tiger (Tirumala limniace); visitors to experience the immersive effect of Common crow (Euploea cora); Common this technique. jay (Atrophaneura aristolochiae); Common Mormon (Papilio polytes); Common tiger (iii) Time Machine (Danaus genutia); Tailed jay (Graphium The Time Machine at Science City is agamemnon); Lemon emigrant (Calopsilia a motion simulator which has been in pomona pomona); Lime Butterfly (Papilio operation since 1997. There is a carriage or demoleous); Plain Tiger (Danaus chrysippus); capsule which accommodates 30 persons and Tawny Coster (Acraea terpsicore). and its doors can be closed. It is made to move in three rotational degrees of freedom (roll, pitch, and yaw) and three translational Duck into Kaleidoscope or linear degrees of freedom (surge, heave and sway). The movement of the capsule is 2. Dynamotion Hall synchronised with a movie projected on a This specially designed building houses screen kept in front of the occupants. Thus enclaves, galleries and facilities such as when the capsule is in motion and the movie an aquarium, a large butterfly enclave, is on, a virtual environment of motion or many interactive exhibits on physics and ride is created for the occupants. bioscience, exhibits on illusions, a laboratory on nano science, a mini theatre for regular science shows, etc. (iv) Mirror Magic Butterfly in Science City We use mirrors in several ways in our daily life. We are also familiar with the images (i) Aquarium that we see in mirrors. But we get excited The aquarium located on ramp level one of (iv) Physical Science when we see some unusual reflections in Dynamotion Hall harbours 16 species of live The ground floor of the Dynamotion Hall of mirrors. These can be done by using mirrors fishes, such as Albino shark, Angel fish, Argus, Science City displays more than 50 physics aligned in special ways. In Mirror Magic hall Asiatica, Bristol Shubunkin, Chitala, Discus, based exhibits including a large Energy of Science City such experience is gained -back fish, Fire-mouth, Mono angel, Ball. It is expected that the exhibits would through 29 mirror exhibits called: Changing Oranda, Oscar, Plecostomus, Silver dollar, stimulate the intrinsic and extrinsic faculty image, Cube, Curving tunnel, Dine with Veil-tail gold fish, and Tiger shark. of visitors and keep them engrossed in 33 Dream 2047, November 2016, Vol. 19 No. 2 India's first Science City turns 20

(viii) Science Shows This interactive and entertaining show is presented regularly on topics like liquid , frozen carbon dioxide, and unexpected science. Curriculum-based demonstrations are arranged for organised school groups on great experiments in electricity, surprising chemical reactions, luminescence, etc. Exploration Hall 3. Maritime Centre This permanent museum is housed in a which are divided into 12 equal longitudinal two-storied building that looks like a ship. segments. There is a huge Earth globe It was developed by Science City, Kolkata in exhibit at the centre on ground floor. There Vertigo Tunnel collaboration with Kolkata Port Trust. With are also large number of panels, multimedia presentations and interactive exhibits in the the scientific process of discovery. museum. An additional attraction It is, however, to be noted that of the exposition is a built-in 3D some of these exhibits can be seen theatre where visitors can witness in ‘Fun Science Gallery’ of some the dynamic phenomena on of the Science Centres developed Earth. by National Council of Science Museum in India. 5. Science Exploration Hall (v) Nano Lab The latest addition to the Science Science City offers guidance and City is the ‘Science Exploration facilities to students to carry on Hall’ for facilitating visitors’ investigative projects on nano entertainment, exploration and science and technology in this science learning. Spread over an laboratory on weekends, holidays area of 5,400 square metres the and vacations. Maritime Centre in Science City building houses the following four galleries: of (vi) Illusion the help of 92 exhibits, spread over a floor Life − A Dark Ride; Panorama on Human With the help of 50 visuals and exhibits this area of 700 sq. metres, the museum depicts Evolution; Science and Technology Heritage section creates an where visitors segments of maritime history, maritime of India; and Emerging Technologies. often cannot believe their own eyes. Here activity and related subjects. colour, brightness and patterns are used to (i) Evolution of Life − create literal optical illusions, physiological A Dark Ride illusions, and cognitive illusions. Titles of This immersive exposition commences with some of the exhibits are: Ghost line, Phantom a dynamic presentation on the formation dots, Bent pencil, Rotating screw, Vanishing of the Earth and evolution of various life doll, Are the shades different? Traffic forms. The exposition comprises 56 robotic motion, Moving butterflies, Rotating square, Glowing flowers, Phantom lines, Dimples or pimples? Pink or white? Breathing squares, Moving ring, and Holograms.

(vii) Power of Ten This panel based exhibition draws visitor’s attention to the relative size of objects in the An exhibit in Maritime Centre Universe. Its illustrations and text are based on a book by Philip Morrison and Phylis Morrison published in 1990. While one 4. Earth Exploration Hall Earth Exploration Hall is a museum that set of 26 photographs depict macro objects Waiting for a dark ride in displays exhibits on physical geography, of size 100 to 1025 cm, the other set of 17 Evolution of Life gallery geology, land, flora, fauna and people of our photographs depict micro objects of size 100 Planet Earth. The hemispherical building of to 10-16. Continued on page 22 25-metre diameter has galleries on two floors Dream 2047, November 2016, Vol. 19 No. 2 32 Lise Meitner – The Mother

of Nuclear Fission Krishna Murty Kommajosyula E-mail: [email protected] Most of us may not have heard of her. head of the physics department of the Kaiser Not surprising! Even the Nobel committee Wilhelm Institute for Chemistry. After the ignored her and awarded the prize to another annexation of Austria, she also had to flee scientist who collaborated with her. But then for Sweden. the Nobel Prize pales into insignificance Unknown to Lise Meitner, Danish when she has a permanent abode on the physicist Niels Bohr made a careful with a (109) arrangement for her escape from Berlin. named after her. The element Meitnerium Even her close partner Otto Hahn was not is named after Lise Meitner, who can be aware of this until days before her departure called the mother of nuclear fission and who in July 1938. Dirk Coster, a Dutch physicist, cleared the path for nuclear fission when it secretly escorted her in that nerve-wracking baffled even a great scientist like Niels Bohr. train journey across Nazi borders into While Meitner collaborated with Otto Hahn the Netherlands. Otto Hahn had given and Otto Frisch in the discovery of nuclear her his mother’s diamond ring: in case it fission of uranium, it was Meitner who gave was required to bribe the frontier guards. the first theoretical explanation of the fission Fortunately it was not given away and her process. nephew’s wife later wore it. From there Born in Vienna on 7 November 1878, she left for Copenhagen and then Sweden, Meitner was one of eight children of her Lise Meitner courtesy Bohr. “Meitner left Germany parents. Her father practised law in Austria. forever with 10 marks in her purse.” When women were not encouraged to study, as “the most beautiful and stimulating that She continued her work at Manne her parents educated her. Her grandmother I have ever heard. . . . He himself was so Siegbahn’s institute in Stockholm, but warned this young girl not to sew on the enthusiastic about everything he taught us Manne Siegbahn, himself a Nobel Prize Sabbath, for the heavens would come that we left every lecture with the feeling that committee member ignored her, partially tumbling down. Lise wanted to test. She a completely new and wonderful due to his prejudice stuck the tip of the needle in the embroidery world had been revealed.” against women in and glanced anxiously at the sky. Nothing She served as a nurse in World science. She would sign happened, took a stitch, waited again. When War 1, handling X-ray equipment, her scientific articles as satisfied that heavens were where they were, but left in 1916 to continue her “L. Meitner.” When she continued with her work. That rational research. Max Planck did not allow the publisher came to scepticism was her constant companion any women to his lectures but know “L. Meitner” was which transformed a shy, introverted girl Meitner was an exception. She later a woman, he stopped into an aggressive researcher. became his assistant. Together with publishing her articles. Meitner was the second woman chemist Otto Hahn she discovered to receive a doctorate in physics at the many new isotopes, working in a Breaking up University of Vienna in 1905. Unsure of remodelled carpenter’s shop because nuclei which subject to select, the university did not On 13 November she attended lectures yet accept women on an Niels Bohr 1938, Hahn met in both mathematics official basis. She became secretly with Meitner and physics; “taking the first woman in Germany to in Copenhagen. On her suggestion, Hahn more notes than the take up professorship in physics at and Strassmann performed further tests on a registered students”. the University of Berlin. uranium product they thought was radium, Her university teacher which in fact was barium. Hahn could not was Ludwig Boltzmann Diamond ring for bribe understand uranium nuclei splitting to who “gave her the When Adolf Hitler came to power form barium and krypton. On 24 December vision of physics as a in 1933, Jewish scientists like her she received a letter from Hahn asking her battle for the ultimate nephew Otto Frisch, Fritz Haber, to interpret this process: “What would truth, a vision she never Leo Szilard were persecuted and physics say about such break-up? …….. lost.” Later she recalled had fled. Meitner was protected by Perhaps you can come up with some sort Boltzmann’s lectures Otto Hahn her Austrian citizenship and the of fantastic explanation. We knew ourselves

31 Dream 2047, November 2016, Vol. 19 No. 2 History of Science that [uranium] can’t actually break up into 1966, Hahn, Fritz Strassmann, and Meitner She also said, “I have no intention [barium].” For the holiday season, she left together were awarded the Enrico Fermi to suggest how atomic energy should be for Sweden by train to visit her 29-year-old Award. She was unable to travel to the US to controlled, beyond expressing my sincere nephew Otto Robert Frisch. While trekking receive it due to her frail physical condition. hope that no occasion will again arise where on the snowy Swedish woods Meitner and She received the Max Planck Medal of the it will be utilised in war. A lasting peace is Frisch vigorously discussed the puzzling German Physics Society in 1949. In 1997, more desirable than the creation of weapons “break-up” process. element 109 was named “meitnerium” in which might lead to the extermination of Frisch recalled later, “We [Frisch and her honour. She is the first and so far the mankind.” Lise Meitner] walked up and down in the only the non-mythological woman thus Meitner spent most of her 70s and snow, I on skis and she on foot (she said and honoured. Additional naming honours are 80s travelling, encouraging women students proved that she could get along just as fast craters on the and on , and the to “remember that science can bring both that way), and gradually the idea took shape main-belt 6999 Meitner. joy and satisfaction to your life.” She says, that this was no chipping or cracking of the “Science makes people reach selflessly for nucleus but rather a process to be explained truth and objectivity; it teaches people to by Bohr’s idea that the nucleus was like a accept reality, with wonder and admiration, liquid drop; such a drop might elongate and not to mention the deep awe and joy that divide itself.” the natural order of things brings to the true While sitting on a trunk, Meitner scientist.” excitedly scribbled out the formulae on a During her next visit to the United piece of scrap paper. Meitner was the first to realise Einstein’s famous equation E=mc2 was States in 1964, Meitner suffered a heart at play here, converting mass into energy. attack. She eventually moved into a “No one really thought of fission before its Cambridge nursing home. She died in her discovery.” Such a “break-up” would release sleep on 27 October 1968 at the age of 89. tremendous amounts of energy! Replicating Einstein had described her as the the experiments, Frisch confirmed this “German Marie Curie!” on 13 January 1939. He coined the term, “fission.” In the early 1939, Meitner wrote Krishna Murty Kommajosyula is Author with Frisch a series of articles to be published of several popular science books published in Nature on the nuclear fission of uranium. by Pustak Mahal, engineering book by Industrial Press, New York. Contributes to Electrified, soon every lab all over the world Lise Meitner in 1946 with reasonable facilities started working on Science Reporter and Electronics For You. this. On a visit to the United States in Radio talker. Leading RCFA specialist. The consequences of nuclear fission 1946, she was treated as a celebrity, “who were devastating. Leo Szilard, Edward left Germany with a bomb in her purse.” Teller, and Eugene Wigner persuaded Albert Hollywood offered to make a movie with VP website Einstein to write to President Franklin D. this theme, but Lise was annoyed when she Roosevelt a warning letter. Apprehending read the script. She was offered a lot more German advancement in nuclear fission, money, but she never gave in. the Manhattan Project was established. Meitner’s collaborator Hahn received Nothing to do with bomb the 1944 for She received the honour of “Woman of the “his discovery of the fission of heavy Year” by the National Press Club. During atomic nuclei. She did not get it, because a dinner at the Women’s National Press of “a mixture of disciplinary bias, political Club, President Harry Truman, remarked, obtuseness, ignorance, and haste.” Meitner “So you’re the little lady who got us into wrote in a letter, “Surely Hahn fully deserved all of this!” Despite distorted press reports Join Vigyan Prasar digital library to the Nobel Prize for chemistry. There is really in Sweden and President Truman’s mix-ups, read online publications. You may also no doubt about it. But I believe that Otto Meitner never worked on the atomic bomb join the discussion forum to ask science Robert Frisch and I contributed something research itself. When she was invited to work and technology related questions and not insignificant to the clarification of the on the Manhattan project at Los Alamos, also answer fellow participants’ queries. process of uranium fission—how it originates Lise refused, “I will have nothing to do with We also have streaming science videos, and that it produces so much energy and that a bomb.” She said that Hiroshima had come science radio serials, online science quiz, was something very remote to Hahn.” as a surprise to her, and that she was “sorry hand-on activities, and many more that the bomb had to be invented.” She later features and programmes related to Woman with a bomb in her purse said, “You must not blame us scientists for science and technology. Log-on to www. Many other honours that Meitner received the use which war technicians have put our vigyanprasar.gov.in in her lifetime overshadowed this Nobel. In discoveries.” Dream 2047, November 2016, Vol. 19 No. 2 30 29 Dream 2047, November 2016, Vol. 19 No. 2 Plastic Pollution and Remedial Measures Dr. Sabdar Aman Chowdhury Plastic is both a boon and a curse in modern a big threat to living species. E-mail: [email protected] . We have been habituated to depend During World War II, there was on it in such a way that this modern time a big surge in scientific research all over on an elastic material then its shape and size is referred to as the Plastic Age, like Stone the world aimed at developing powerful change. But when the force is removed, it Age, Copper Age, Bronze Age, and Iron Age weapons. Side by side, a number of parallel gets back to its previous shape and size. On earlier. Plastic is a lightweight, waterproof, products were also invented, one of which the other hand, plastic substances can change corrosion-resistant, handy, and cheap was plastic. Human beings started to enjoy their shape according to the applied force, material. But there are also some demerits of the advantages of plastic products from that but do not get back to their previous shape this material. time. And now it has established itself as one when the force is removed. There are two What is a plastic? It is a chemical of the most essential materials for mankind. types of synthetic plastics, viz., thermoplastics substance known as a polymer made from For example, Nylon, Terylene, synthetic (e.g. polyethylene, polypropylene, PVC, organic chemicals. It is a macromolecular rubber (Gutta Percha, polyneoprene, etc.) and thermosetting plastics (e.g. substance that is made up of long chains of Buna-S, etc.), polyethylene (popularly Melamine, Bakelite, etc.). Thermoplastics small molecular units known as monomers. known as Polythene), polyvinyl chloride can be softened repeatedly on application There are many natural polymeric substances (PVC), Teflon, Melamine, polypropylene, of heat, can be stored in cold state and can such as proteins, RNA, DNA, starch, polystyrene, Bakelite, etc., are all artificial or be recycled. While thermosetting plastics are cellulose, natural rubber, etc. They are all synthetic polymers and play important roles rigid and cannot be softened on application biodegradable; that is, they easily decompose in our daily life. of heat. They cannot be recycled. when left in the nature and do not pollute The term plastic has come from the The popularity of plastic products the environment. But there are man-made word “plasticity”, which is a physical property can be justified by their varied uses, a few polymers such as plastics which are non- just opposite to another physical property examples of which are given in Table 1. biodegradable and their presence in nature is known as elasticity. When a force is applied In addition of those listed, the advantages

Table 1: Uses of selected polymers and corresponding name of the monomers Name of polymer Name of monomer unit/s Properties and uses Polyethylene Ethylene Used to make carry bags, bottles, electrical insulators, etc. It is little harder than polyethylene and lighter and very resistant to Polypropylene Propylene bending. It is used to make furniture, TV body, computer spare parts, buckets, etc. It is transparent and is used to make toys, cups, plates, water glasses, Polystyrene Styrene cream pots, combs, etc. Teflon Tetrafluoroethylene High melting point. Used to make non-stick cookware, tape, etc. It is a very good substitute of rubber. It is used to make pipes, floor tiles, PVC Vinyl chloride raincoats, gumboots, sandals, etc. Terylene or Dacron Ethylene glycol and terephthalic acid Used to make thread, cloth, seatbelt, magnetic tape, etc. (Polyester) Hexamethylene diamine and adipic To make tooth brush, hosiery products, textiles, ropes, cloth, tarpaulin, Nylon 66 acid net, carpet, mattress, etc. Glyptal or alkyd resin Ethylene glycol and phthalic acid. Used in paint industry. Perspex glass is a very popular name and is widely used in making Perspex Methyl methacrylate contact lens, sheet, rod, prism, lens of spectacles and binocular etc. Buna-S Butadiene and styrene Artificial rubber, used to make tyres. Orlon Acrylo nitrile Used as thread and fibre. Saran Dichloroethylene Used to produce seat cover of cars. Bakelite Phenol and formaldehyde Used to make electrical plug, switch, etc.

Dream 2047, November 2016, Vol. 19 No. 2 28 Environment of plastics over other materials are their and carcinogenic. Cheaper plastics in human, heart disease in adults, liver light weight, corrosion resistance, heat and are highly contaminated with toxic enzyme abnormalities, type 2 diabetes, electrical insulation, resistance to chemicals, monomers. increased possibility of breast water and air, long , abrasion 6. Plastic bags when washed down a drain in woman and asthma. resistance, low production and maintenance or blown into a river end up in the sea There are many other harmful effects cost, etc. These are the reasons that have made affecting marine as follows: of plastics and thus it is high time to rethink them an extraordinary material. It has become (a) Marine turtles, fish, etc., get entangled over our dependence on plastics and to a good substitute of traditional materials in plastic bags and die. search for alternatives. The Golden Three such as cloth, paper, jute, etc., especially for (b) Plastic bags look like jellyfish and are ‘R’s for solid waste management are ‘Reduce’, packaging where the use of plastics lead to consumed by many of the marine ‘Reuse’ and ‘Recycle’. Firstly, we have to phenomenal savings (Table 2). animals causing choking or severe be less dependent on plastics (Reduce) From the descriptions in Table 1 and damage to their digestive system. and secondly, we should not throw away Table 2 it is clear why plastics have become (c) When sea birds eat marine animals or used plastic materials (Reuse). The most so popular. The present-day situation is that directly eat plastic debris floating in important among the Golden Three ‘R’s is more than 150 million tonnes of plastics the sea, plastics get into their digestive Recycling where we can help this process have accumulated (from a report published system causing gastrointestinal by collecting used plastics appropriately. in 2006) all over the world, which is quite blockage. But the main drawback of recycling is that alarming and poses serious threat to the (d) Plastic particles smaller than 1 mm are the recycled plastics do not contain a pure environment. The hazardous effects due known as microplastics, which become polymer; that is, they are not homogeneous to plastic pollution may be summarised as heavy enough to sink when colonised since different types of polymers are mixed follows: by microorganisms. These particles up. Not only that, at the time of their first 1. Plastic articles never degrade in nature obstruct the flow of oxygen when they synthesis, a number of other compounds causing huge accumulation of solid reach the seabed causing the death of such as pigments, fillers, additives, etc., are wastes. As a result, the environment is oxygen-dependent marine flora and added which also get into the recycling unit. being polluted as well as the ecological fauna. Dirty and contaminated plastics are also balance is greatly affected. (e) Toxic chemicals leaching out of plastics responsible for the production of poor-quality 2. Plastic carry bags clog the water ways contaminate the sea food and magnify recycled plastics. To obviate these difficulties and drains resulting in water logging, through food chain. some coded symbols of the monomer units especially in urban areas. 7. Based upon their similar are required to be embossed in thermoplastic 3. Blocked sewers help in breeding of physicochemical properties, other products in order to sort them before and mosquitoes, bringing in toxic chemicals such as DDT or DDE recycling to improve the homogeneity of the secondary effects of plastic pollution. are adsorbed by the plastics and are recycled product. Although this technique Rain water collected in used plastic likely to leach out over time. is followed by most of the countries all over bags also helps in breeding of 8. The ground water do not recharge the world, the scenario is a little different mosquitoes. due to blockage of rainwater by plastic in India where neither this type of coding 4. Workers in the plastic industry suffer bags in the topsoil. is strictly followed nor is the Government from several physiological disorders 9. Plastic articles cause air pollution on making it mandatory for the manufacturers such as disorders in kidney, lungs and burning. to do so. Still, the silver lining is that the liver. 10. Plastic additive 2,2-bis (4- solid waste management situation in India 5. Some types of plastics bags, containers, hydroxyphenyl) propane popularly is a little better than many other countries etc., react with food, causing serious known as Bisphenol A or BPA that due to the role played by the rag pickers who health hazards to the users. Although is used in hard plastics (especially help sort plastic wastes in a big way. plastic is a polymeric substance, all in polycarbonate plastics and epoxy Apart from the Golden Three ‘R’s, the the monomers that make it up do not resins) is leached out from food other way out of solid waste management is add up and remain in the product. containers and mimics oestrogen their disposal by landfilling and incineration. The safety level of such monomer hormone. It causes reproductive But there has also been some serious harmful is often 1ppm, else they are toxic disorders by affecting egg maturation effects arising from it. These are: 1. Landfilling by plastic can cause infertility of as they remain Table 2: Phenomenal savings due to the use of plastics without being decomposed. Savings in Reduction in amount in percentage when plastic 2. Plastic bags release toxic chemicals is used in place of cloth, paper, jute, etc. into the groundwater from landfill sites. Weight of packaging Reduced to ~25% 3. Phthalates (used as a plastic softener) Volume of waste Reduced to ~40% are released by some plastics from Energy requirement Reduced to ~50% Cost of packaging Reduced to ~30% Continued on page 25 27 Dream 2047, November 2016, Vol. 19 No. 2 2016 Nobel Prizes in Science Biman Basu E-mail: [email protected]

Physiology or Medicine controls important physiological functions knots, shuttles, rotors, chains, pumps, axles, Biologists use the term ‘’ for where cellular components need to be switches, memory devices and even a nano- the process which cells use to recycle its degraded and recycled. Autophagy can car – all at the scale of . According various components. The word autophagy rapidly provide fuel for energy and building to the scientists, future applications of nano- originates from the Greek words auto-, blocks for renewal of cellular components, scale machines could range from delivering meaning “self”, and phagein, meaning “to which is essential for the cellular response drugs to computer memory. eat”. Thus, autophagy denotes “self-eating”. to starvation and other types of stress. After The success came after many years of infection, autophagy can eliminate invading struggle. In the mid-20th century, as part intracellular bacteria and viruses. Autophagy of efforts to build increasingly advanced also contributes to development and molecules, chemists were attempting to cell differentiation. produce molecular chains in which ring- shaped molecules were linked together. Chemistry Normally, molecules are held together by How small can you make machinery? This strong covalent bonds in which atoms share is the question that Nobel Laureate Richard . The dream was to instead create Feynman, famed for his 1950s’ predictions mechanical bonds, where molecules are of developments in nanotechnology, interlocked without the atoms interacting posed at the start of a visionary lecture in directly with each other. 1984. He was convinced it was possible to The first step towards a molecular build machines with dimensions on the machine was taken by Jean-Pierre Sauvage nanometre scale. These, he said, already in 1983, when he succeeded in linking existed in nature, giving example of bacterial two ring-shaped molecules together to flagella, which make bacteria move forward. form a chain, called a ‘catenane’ in which the molecules were linked by a mechanical But building machines that can be seen only under a microscope still appeared a distant bond. The second step was taken by Fraser For a long time scientists knew little about dream. The 2016 Nobel Prize in Chemistry Stoddart in 1991, when he developed a the mechanism of autophagy till Yoshinori has been awarded jointly to three scientists ‘rotaxane’. He threaded a molecular ring Ohsumi of Tokyo Institute of Technology, – Jean-Pierre Sauvage of the University of onto a thin molecular axle and demonstrated Tokyo, Japan used baker’s yeast to identify Strasbourg, France, Sir J. of that the ring was able to move along the axle. essential for autophagy. He then went Northwestern University, Evanston, USA, The first molecular motor was developed by on to elucidate the underlying mechanisms and Bernard L. Feringa of the University Bernard Feringa; in 1999 he got a molecular for autophagy in yeast and showed that of Groningen, the Netherlands – “for the rotor blade to spin continually in the same similar sophisticated machinery is used design and synthesis of molecular machines”. direction. in human cells to recycle components. The three scientists have built molecular The Nobel Prize for 2016 in Medicine or Physiology has been awarded to Oshumi for his discoveries of mechanisms for autophagy Ohsumi’s discoveries led to a new paradigm in our understanding of how the cell recycles its content and also to understanding the fundamental importance of autophagy in many physiological processes, such as in the adaptation to starvation or response to infection. It was found that mutations in autophagy genes can cause disease, and the autophagic process is involved in several conditions including cancer and neurological disease. It is mainly because of Ohsumi’s work that we now know that autophagy (l to r) Jean-Pierre Sauvage, J. Fraser Stoddart, and Bernard L. Feringa Dream 2047, November 2016, Vol. 19 No. 2 26 Nobel Prizes 2016 in Science The work of the three scientists in the 1970s and 1980s laid the foundations for predicting and explaining bizarre behaviours that experimentalists discovered at the surfaces of materials, and inside extremely thin layers. These include superconductivity – the ability to conduct electricity without resistance – and magnetism in very thin materials. The three scientists could explain the behaviour of exotic matter through the mathematical concept of topology, which describes properties that remain unchanged if an object is deformed but not torn. In 1973, Thouless and Kosterlitz, working at (l to r) David J. Thouless, F. Duncan M. Haldane, and J. Michael Kosterlitz the University of Birmingham, UK, used the concept of topology to explain certain Physics matter physics is now one of the most kinds of phase transition. They showed that Strange things happen to properties of vibrant fields in physics. The Nobel Prize in topological phase transitions – in which materials when present on surfaces or inside Physics for 2016 has been awarded jointly a material switches between states with extremely thin layers that can be considered to David J. Thouless of the University of different topologies – were possible in thin two-dimensional, compared to the three Washington, Seattle, USA, F. Duncan layers of materials. In 1982, Thouless also dimensions with which we are familiar. The M. Haldane of Princeton University, NJ, explained a phenomenon known as the physics that takes place in two-dimensional USA, and J. Michael Kosterlitz of Brown quantum Hall effect and showed that it was, matter is very different from that we University, Providence, USA, for their again, a topological phenomenon. recognise in the world around us. New theoretical explanations of strange states of [Detailed accounts of the work of the collective phenomena are being continually matter in two-dimensional materials, known laureates will be published in forthcoming discovered in these flatlands, and condensed as topological phases. issues.]

Plastic Pollution and Remedial Measures (continued from page 27)

landfill sites that are known to cause (especially plastic-bag-free) zones as much as 8. Don’t keep dry food items such as tea birth defect, birth of premature babies possible. Getting habituated without using leaves, , cashew nuts, raisins, and infertility in men. Phthalates can plastic bags and other products would help biscuits, etc., in plastic containers for mimic the female hormone oestrogen reduce its use to a great extent. a long time as they catch the smell of and are suspected to be responsible for There are some do’s and don’ts as a the plastics and get contaminated. early puberty in girls. part of remedial measures. These are: 9. Avoid PVC bags for school children. 4. Incineration of plastics releases 1. Never use plastic carry bags of 10. Crush bottles of packaged drinking carcinogenic chemicals called dioxins thickness below 50 microns as they water after single use and dump them into the air. They are also responsible readily form microplastic particles and appropriately. for developmental disorders and other can release toxic chemicals. 11. Thermosetting type of plastics such as health problems. 2. Never use plastic bowls (even branded Melamine or Teflon is comparatively Therefore the situation is quite critical and microwave-safe) in the microwave safer and articles made of them can be and it cannot be changed overnight. At least oven as they react with food. used. what we can do to begin with is to play 3. Plastic bath tubs are not safe, especially Since the present age is referred as the some primary roles such as carry a jute or during winter when warm water is Plastic Age, therefore, we cannot completely cotton bag every morning when we go to used. avoid the uses of plastics. Apart from all the market, and to boldly refuse any kind of 4. Never pour any just-prepared hot food the negative sides, it can be reiterated that plastic carry bag offered by the shopkeepers. item in a plastic bowl or container. the situation is still under control. What We can discourage our family members, 5. Try to use biodegradable plastics we have to do is to be little more conscious colleagues, friends, close circles from using such as corn starch bags (soluble and and to have the attitude to be environment plastic carry bags. We can educate our digestible to animals) as much as friendly. children at home and students in educational possible. institutes on the bad effects of using plastics 6. Do not throw plastic articles here and Dr. Sabdar Aman Chowdhury is Assistant recklessly. Academic persons should shoulder there. Professor of Chemistry at Bolpur College some responsibility by campaigning for 7. Do not allow plastic bags to clog the (Affiliated to The University of Burdwan), mass awareness and by creating plastic-free drains by regularly cleaning them. Bolpur, Birbhum, West Bengal-731204. 25 Dream 2047, November 2016, Vol. 19 No. 2 Anal Fistulas— All You Want to Know About Dr. Yatish Agarwal E-mail: [email protected]

Put simply, an anal fistula is a small tunnel-like track that develops • Rectal injury or following a complication of surgery near the between the lower end of the bowel (rectum) and the skin near the anus anus. The anus is the external opening through which faeces are • Rectal cancer expelled from the body. Just inside the anus are a number of small • Hidradenitis suppurativa: a long-term skin condition that glands. If one of these glands get blocked, an abscess—an infected causes abscesses and scarring cavity—may form. An anal abscess is usually treated by surgical • Crohn's disease: a long-term inflammatory condition of the drainage, although some drain spontaneously. About 50 per cent of bowel these abscesses may develop into a fistula, in which a small tunnel connects the infected gland inside the anus to an opening on the Symptoms skin of the buttocks around the anal opening. A patient of fistula-in-ano may present with a number of signs and Often given the name of ‘fistula-in-ano’ in medical parlance, symptoms: it is a troublesome condition, causes bleeding and discharge when passing stools, and can be quite painful. While many of the patients Anorectal pain with anal fistula experience a persistent discharge through the skin Most patients complain of pain and swelling around the anus. They opening around the anus, others may suffer at the hands of recurrent may also experience pain on bowel movement. anal abscesses, particularly, if the outer opening of the tract on the skin gets closed. Discharge from the opening around the anus Managing an anal fistula is a bit of tricky affair; the only A large majority of patients complain of a bloody or foul-smelling cure being surgery. However, unless it is removed in entirety, it can pus discharge from the outer perianal skin opening. The pain may recur. The surgery of complicated fistulas is also not free of possible diminish once the pus gets drained and the fistulous track cleans up. complications. A persistent perianal discharge may produce irritation of the skin.

Causes Rectal bleeding Most anal fistulas Some patients may suffer rectal bleeding. result from previous or existing anal abscesses. Anal abscess Ninety per cent of these Recurrent anal abscesses can worsen the misery of a patient. The abscesses are the result victim experiences repeated attacks of anorectal pain, swelling, of an acute infection in redness of the perianal skin (due to cellulitis) and fever. the internal glands of If you notice any of these symptoms, you should see your the anus. Occasionally, family physician, or better still, a colorectal or general surgeon. bacteria, faecal material or foreign matter clog an anal gland and tunnel into the tissue around the anus or rectum, where it may then collect in a cavity called an abscess. When these abscesses break down, a track may form between the anus on one end, and the perianal skin on the other. These tracks may have multiple side branches, extend as a horseshoe to the other side, and be associated with one or more cavities. A small number of fistulas may be associated with other disease processes. These include the following: • Tuberculosis • Sexually transmitted diseases • Diverticulitis: infection of the small pouches that can stick out of the side of the large intestine (colon) Dream 2047, November 2016, Vol. 19 No. 2 24 Mediscape Tests and diagnosis muscles, the ring of muscles that open and close the anus, which could Usually, a clinical potentially result in loss of bowel control (bowel incontinence). evaluation – including Fistula surgery generally requires only a short hospital stay. a digital rectal Very large or deep fistula tunnels may, however, require a more examination – is complicated surgery. sufficient to diagnose an anal fistula, but some patients may require further tests. Fistulotomy A surgeon can mostly diagnose an anal The most effective and most common type of surgery for anal fistulas fistula by examining the area around the anus. is a fistulotomy. This involves cutting along the whole length of the He or she will look for an external opening on the fistula to open it up so it heals as a flat scar. skin. If this is visible, your physician will then try to This surgery, however, only works for fistulas that don’t pass determine the depth and direction of the fistula tract. through much of the anal sphincter muscles. In patients where the Often a discharge can be produced from the external opening. fistula cuts across a large part of the anal sphincter, the so-called Some fistulas may not be visible on the skin’s surface. In this trans-sphincteric fistula, this is not the ideal method since it would case, the surgeon may carry out or ask for some additional tests. The carry a high risk of bowel incontinence. simplest is proctoscopy. This technique uses a special instrument to peep inside the anus and rectum. Seton technique The surgeon may also seek an anorectal ultrasound or MRI of If the fistula passes through a significant portion of anal sphincter the anal area to better define the fistula tract. muscle, the surgeon may initially recommend inserting a seton. A If a fistula is found, the surgeon may also want to do further seton is a piece of surgical thread that is left in the fistula for several tests to see if the condition is related to tuberculosis of the intestine. weeks to keep it open. This allows it to drain and helps it heal, while Among these studies are blood tests, X-rays, and colonoscopy. A avoiding the need to cut the sphincter muscles. colonoscopy, in which a flexible, lighted instrument is inserted into Loose setons allow fistulas to drain, but don’t cure them. To the colon via the anus, is performed under conscious sedation. cure a fistula, tighter setons may be used to cut through the fistula slowly. This may require several procedures that your surgeon can Treatment options discuss with you. The seton technique is as ancient as Ayurveda and Since anal fistula rarely heals if left untreated, surgery is usually has been practiced for thousands of years in India. necessary. It is best performed by a colon and rectal specialist, although most general surgeons are fairly adept at performing the Advancement flap procedure operation. An advancement flap procedure may be considered if a fistula passes During surgery, the physician will assess the depth and extent through the anal sphincter muscles and having a fistulotomy carries of the fistula tract. Most fistulas are treated with a fistulotomy, in a high risk of causing incontinence. which the skin and muscle over the tunnel are cut open, converting This involves cutting or scraping out the fistula and covering it into an open groove. This allows the fistula tract to heal from the the hole where it entered the bowel with a flap of tissue taken from inside out into a flat scar. inside the rectum, which is the final part of the bowel. A more complex fistula may require placement of surgical This has a lower success rate than a fistulotomy, but avoids the thread called a seton for at least six weeks, after which a definitive need to cut the anal sphincter muscles. surgical repair is done. Other techniques include filling the fistula with special glue, LIFT procedure blocking it with a special plug, or covering it with a flap of tissue. The ligation of the intersphincteric fistula tract (LIFT) procedure They may also sometimes be used. is a relatively new treatment for anal fistulas. It is designed as a All these procedures have different benefits and risks. You can treatment for fistulas that pass through the anal sphincter muscles, discuss this with your surgeon. The best option for you will depend where a fistulotomy would be too risky. During the treatment, a cut on the position of your fistula and whether it is a single channel or (incision) is made in the skin above the fistula and the sphincter branches off in different directions. Sometimes you may need to have muscles are moved apart. The fistula is then sealed at both ends and an initial examination of the area under general anaesthetic to help cut open so it lies flat. determine the best treatment. Your surgeon will talk to you about the options available and Fibrin glue which one they feel is the most suitable for you. Surgery for an anal Treatment with fibrin glue is currently the only non-surgical option fistula is usually carried out under general anaesthetic. The aim of for anal fistulas. The surgeon injects special glue into the fistula surgery is to heal the fistula while avoiding damage to the sphincter while the patient is under a general anaesthetic. The glue helps seal 23 Dream 2047, November 2016, Vol. 19 No. 2 Mediscape the fistula and encourages it to heal. Infection It is generally less effective than fistulotomy for simple fistulas This may require a course of ; severe cases may need to be and the results may not be long-lasting, but it may be a useful option treated in hospital. for fistulas that pass through the anal sphincter muscles because they do not need to be cut. Recurrence of the fistula The fistula can sometimes recur despite surgery Follow-up treatment Following a fistula surgery, the treating surgeon may recommend Bowel incontinence soaking the affected area in a warm bath and taking stool softeners This is a potential risk with most types of anal fistula treatment, or laxatives for a week. Since you may also experience some pain or discomfort in the area after surgery, you may require pain pills. Most although severe incontinence is rare and every care is taken to prevent fistulas respond well to surgical treatment. it. The level of risk will depend upon a number of factors like how the fistula is located and the specific procedure that’s being done. Potential risks of anal fistula surgery Like any type of treatment, treatment for anal fistulas carries a Prof Yatish Agarwal is a physician and teacher at New Delhi’s number of risks. The main risks are: Safdarjung Hospital. He has authored 47 popular health-books.

India’s first Science City turns 20 (continued from page 32) animal models divided into seven sections to (iii) Science & Technology showcase the milestone events of evolution Heritage of India and representative life forms of respective It portrays 5,000 years of Science and eras. Visitors are taken in a slow-moving Technology heritage of India through electric car for this immersive experience, varied period setting dioramas, models supplemented by computer-controlled and interactive exhibits with computer special light and sound effects. Each section kiosks. It brings forth India’s contribution is introduced to the visitors through a special in ancient science and how it pioneered in audio-video presentation. the philosophical developments in scientific principles. India brimmed with tremendous (ii) Panorama on knowledge on various metallurgical practices, Human Evolution textile weaving, wood crafts, coin making, A section of This digital panoramic presentation is a ship building, architecture and various Emerging Technologies gallery unique immersive experience depicting traditional technologies. Here, the Indus tube, Lift yourself, Revolve faster, Tensegrity the important milestones during the last 6 Valley Civilisation has been depicted as a structure, etc. million years of human evolution. It starts large diorama in a period setting during the Dr. Tapan Kumar Ganguly, a Chemical with a static panoramic image of size 10 times of Harappa and Mohenjo-daro. Technologist, was the first Director of m × 122 m showcasing important events Science City. Shri Arijit Dutta Choudhury, of human evolution. This is followed by a (iv) Emerging Technologies a Mechanical Engineer, heads the Kolkata 12-minute film with voice over in three This gallery gives us an over view of the Science City since 2009. The entire activities languages on human evolution, projected emerging technologies in various fields like of Science City are managed by seventy-odd on the giant cylindrical screen with the help robotics, energy, ICT, medical sciences, staff members. of eight powerful digital projectors, contains human genomics, alternative fuels, encoding Kolkata Science City has been visited actual shoot across South Africa and India. of information etc. and the role of quantum so far by more than 2 crore 35 lakh visitors mechanics, information and communication till March 2016, including 14,91,730 visitors technologies and molecular biology in these during the year 2015-16. technologies. Dr Jayanta Sthanapati, former Deputy 6. Outdoor Science Park Director General of National Council of The Science Park is an outdoor exposition Science Museums, has recently completed comprising Rope Way, Musical Fountain, his study on ‘History of Science Museums Road Train, Monorail Cycle, and a set of and Planetarium in India’, as a research 36 participatory exhibits on physics, such project sponsored by the Indian National as A simple camera, A swing is a pendulum, Science Academy. He holds PhD (Physics) Indus Valley market scene Action and reaction, Ellipsoidal speaking and PhD (History) degrees. Dream 2047, November 2016, Vol. 19 No. 2 22 Recent Developments in Science and Technology Biman Basu E-mail: [email protected] Earth-sized, life-friendly HARPS observations from 2005 to early common primitive atmospheric planet discovered 2014, the signal of a possible planet came on all the Earth-sized planets in the solar An almost Earth-sized planet with conditions through loud and clear, following which system.” In other words, all the ingredients suitable for life has been discovered around the discovery of Proxima b was announced for life are most likely available there. If a star very close to our solar system. The (Nature, 25 August 2016 | doi:10.1038/ that is the case, the believe, the star is , a lying nature19106). formation biochemical processes we can call at a distance of just 4.2 light years – the Many physical parameters of Proxima life on Proxima b is inevitable rather than a nearest star to Earth (leaving out the ). b are still uncertain, but it is known that rare event. Proxima Centaury is much cooler than our although it orbits its parent star quite Proxima b is more than 40 trillion Sun; it has an effective temperature of only close (only 7.5 million km) the it kilometres away, a distance that would take around 3,050 kelvin, a luminosity of 0.15 receives from the red dwarf star is only about around 30,000 years to reach with current per cent of that of the Sun. It has a radius 70 percent of the solar radiation received technology. However, the planet is close 14 per cent of the radius of the Sun and a on Earth, making its surface temperature enough to give scientists confidence that mass of about 12 per cent of the they can develop a mass of the Sun. The planet, that would be able to reach it named Proxima b, has a mass within the scale of a human about 1.3 times that of Earth life time and they believe and orbits Proxima Centauri at robotic probes could be sent to a distance of roughly 7,500,000 Proxima b in years to come. km with an orbital period of approximately 11.2 Earth days. Sunflowers move by Although astronomers still don’t the internal clock have any knowledge about the The sunflower plant is known planet’s radius and density, they to follow the Sun. Young say it lies within the ‘habitable’ sunflower plants track the Sun zone of its host star – the range from east to west during the of distances at which liquid water day and then reorient during could be stable on its surface. the night to face east at dawn. The discovery was made Each night the plants reverse by astronomers who have been Artist’s view of the Proxima b with red dwarf their movement, swinging carrying out intense search for star Proxima Centauri in the background. from west to east in order to be planets around Proxima Centauri the first to face the Sun when it for more than 15 years, using instruments somewhat lower than on our planet. rises over the horizon at daybreak. But mature such as the and Visual Echelle Moreover, the slightly larger mass may make plants lose this capacity of movement. Plant Spectrograph (UVES) and the High Accuracy Proxima b’s atmosphere slightly denser than biologists of the University of , Radial velocity Planet Searcher (HARPS), Earth’s enabling a stronger greenhouse effect Davis, have now discovered how sunflowers at the European Southern Observatory in and making it amenable to life. use their internal circadian clock, acting on Chile. They used the instruments to detect According to the astronomers, there growth hormones to follow the Sun during the slight wobbles in the star’s movement are three important ingredients necessary the day as they grow (Science, 5 August 2016 | caused by the gravitational tugs of orbiting for life. “First, we need rock, and Proxima b doi: 10.1126/science.aaf9793). Scientists planets. indeed is a planet that certainly has a rocky have known about the sunflower plants’ The first sign of a wobble was surface. Second, the most common molecule sun-seeking behaviour since 1898, when detected in 2013, but the signal was not in the Universe, water, has to be present. We botanist John Schaffner described it in convincing. So the astronomers carried out have no evidence of this, but water can be the journal Botanical Gazette. But no one a systematic study and focussed HARPS found everywhere in space and there are no had previously thought to associate it with on Proxima Centauri every night from 19 reasons why it would not exist on the surface circadian rhythms. January 2016 up to 31 March of this year. of Proxima b – and the temperatures on its Circadian rhythms are physical and After they combined this new data with surface likely allow the water to be liquid behavioural changes in that UVES observations from 2000 to 2008 and and for oceans as well. Third, there needs follow a roughly 24-hour cycle, responding to be carbon dioxide, but that is simply a primarily to light and darkness in an 21 Dream 2047, November 2016, Vol. 19 No. 2

of the world’s leprosy patients live in India. However, experts believe that these figures represent just a fraction of the true picture of people affected by leprosy. Lack of awareness, insufficient access to medical treatment and severe stigma surrounding leprosy mean that hundreds of thousands more could be living with the effects of the disease, going untreated. Leprosy is a crippling disease that often results in a lack of ability to feel pain and thus loss of parts of extremities due to repeated injuries or infection due to unnoticed wounds, often causing gross disfiguring of the fingers and limbs. Leprosy can no longer be treated by the conventional multi-drug therapy (MDT). To control the spread of the The sunflower’s movement to follow the Sun is driven by the plant’s internal clock. disease, the first exclusive for leprosy has been developed by the National Institute ’s environment. They are found in the direction of light – causes the stem to of Immunology (NII), New Delhi, which most living things, including animals, plants grow more on one side than another, and has been already approved by the Drug and many tiny microbes. Sunflowers, like therefore sway east to west during the day, Controller General of India (DCGI) and the animals, have a circadian rhythm. During making the plant follow the motion of the Food & Drug Administration (FDA) of the the day, this system sends messages to the Sun in the sky. US. eastern sides of their stems, telling those The study found that as the sunflower The vaccine, made from killed cells to grow slightly longer, thus making matures and the flower opens up, overall bacterium called Mycobacterium indicus the sunflowers lean westward. At night, the growth slows down and the plants stop pranii (MIP), is an ‘immunotherapeutic’ message reverses, and the sunflowers tilt moving during the day and settle down facing vaccine for leprosy, which means it harnesses back toward the east. east. According to the researchers, mature the ability of body’s to The researchers carried out a series sunflowers prefer to face east because east- combat infection or disease. It enhances the of experiments with sunflowers in the field, facing sunflowers heated up more quickly in immune system’s resistance to the disease. in pots outdoors, and in indoor growth the morning – and attract more pollinating The vaccine is being launched on a pilot chambers to study their daily movement. By insects because “ like warm flowers”. basis in five districts in Bihar and Gujarat tying the plants to stakes so that they could where the vaccine will be administered as a not move, or turning potted plants around India develops world’s preventive measure to people living in close daily so that they were facing the wrong way, first leprosy vaccine contact with those infected. it was found that the plants’ ability to track Leprosy, caused by the bacteria, According to Dr. Soumya the Sun could be disrupted. The researchers Mycobacterium leprae, affects around 1.25 Swaminathan, Director General, Indian found that following the Sun provides a lakh people every year in India. About 60% Council of Medical Research (ICMR), trials growth boost to the plants, while restricting their movement caused reduced production of biomass. When the plants were moved into an indoor growth chamber with fixed overhead light, they continued to swing back and forth for a few days, which provided the clue that the movements were driven by an internal clock. Exploring further, the researchers identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day or on the other side at night. According to them, there appear to be two growth mechanisms at work in the sunflower stem. The first sets a basic rate of growth for the plant, based on available light. The second – controlled Gross disfigurement caused by leprosy. by the circadian clock and influenced by Dream 2047, November 2016, Vol. 19 No. 2 20 New Horizons had shown that the vaccine, if administered to people in close contact with affected persons, could bring down cases by 60 per cent in three years. It expedited cure rates if given to people with skin lesions. Testing of the MIP vaccine that took place in 2005 showed that the vaccine remains effective for seven to eight years, after which a booster dose would need to be given. If the new project proves to be successful, it is hoped that the vaccine will be used across the country for mass immunisation of contacts of those affected by leprosy. If the pilot phase shows satisfactory results, the programme will be implemented in other high-prevalence districts across the country. The government have already Food packaging made of milk protein is safer than synthetic plastic films. begun screening in 50 high-prevalence districts across the country. A total of 7.5 come up with one made of the milk protein made some improvements by incorporating crore people were screened out of which casein, which is not only biodegradable citrus pectin into the blend to make the 5,000 had leprosy. The next phase will cover but is also edible. This was announced at a packaging even stronger, as well as more 163 districts. meeting of the American Chemical Society resistant to humidity and high temperatures. At present, one of the greatest barriers at Philadelphia, USA, on 22 August. After a few additional improvements, the to ending leprosy is the stigma that persists The milk protein-based plastic film casein-based packaging was found to be in India, with numerous laws discriminating was developed by a team of researchers led by almost identical with plastic wraps used in against people affected by the disease. This Peggy Tomasula at the U.S. Department of groceries and stores, but less stretchy and discourages many from seeking treatment Agriculture. These casein-based films are up better at blocking oxygen. The material is because they fear being ostracised once to 500 times better than plastics at keeping made almost entirely of proteins and is edible. people know they have leprosy. It is hoped oxygen away from food and, because they According to the researchers nutritious the new vaccine will change the situation are derived from milk, are biodegradable, additives such as vitamins, probiotics and and help bring those threatened with the sustainable and edible. According to the nutraceuticals could be included in the disease into the mainstream. researchers, the protein-based films are future for food packaging. The group plans powerful oxygen blockers that help prevent to keep making improvements, and hopes Safer food packaging made food spoilage. When used in packaging, they to bring this casein film packaging on store from milk protein could prevent food waste during distribution shelves within 3 years. Plastics are found everywhere in the modern along the food chain. world amidst growing opposition to the The researchers arrived at the final Biman Basu is a former editor of the widespread use of these synthetic materials. formulation after several trials and errors. popular science monthly Science Reporter, Being non-biodegradable, plastic waste Their first attempt using pure casein resulted published by CSIR, He is a winner of the remains in the environment almost forever, in a strong and effective oxygen blocker, but 1994 ‘NCSTC National Award for Science affecting vegetation, wildlife and also the product was relatively hard to handle and Popularisation’. He is the author of more waterways. would dissolve in water too quickly. They than 45 popular science books. One of the most widespread uses of plastic is in the form of films for packaging, including food packaging. At the grocery Dream 2047 store, most food items such as meat, bread, Articles Vigyan Prasar invites original popular science articles cheese, snacks, etc., come wrapped in plastic invited packaging. The plastic films used for food for publication in its monthly science magazine Dream packaging is mainly petroleum-based, which 2047. At present the magazine has 35,000 subscribers. The is not sustainable. Moreover, not only does article may be limited to 3,000 words and can be written in this create a lot of non-recyclable, non- English or Hindi. Regular coloumns on i) Health ii) Recent biodegradable waste, but some plastic films developments in science and technology are also welcome. are suspected of leaching potentially harmful Honorarium, as per Vigyan Prasar norm, is paid to the chemicals into food. To address these author(s) if the article is accepted for publication. For details issues, scientists have been trying t develop please log-on to www.vigyanprasar.gov.in or e-mail to dream@ a packaging film that is biodegradable and safe for food packaging. They have now vigyanprasar.gov.in

19 Dream 2047, November 2016, Vol. 19 No. 2