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| SCIENCE & TECHNOLOGY |
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The medical miracle
Prof Yash
Pal PROF YASH PAL We know that earth is rotating on its axis. What keeps it rotating on and on? Will it stop rotating some day just like a spinning top which loses its speed with time? |
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The medical miracle
A 30-year-old Spanish woman has made medical history by becoming the first patient to receive a whole organ transplant grown using her own cells.
Experts said the development opened a new era in surgery in which the repair of worn-out body parts would be carried out with personally customised replacements. Claudia Castillo, who lives in Barcelona, underwent the operation to replace her windpipe after tuberculosis had left her with a collapsed lung and unable to breathe. The bioengineered organ was transplanted into her chest last June at the Hospital Clinic in Barcelona. Four months later she was able to climb two flights of stairs, go dancing and look after her children - activities that had been impossible before the surgery. Ms Castillo has also crossed a second medical frontier by becoming the first person to receive a whole organ transplant without the need for powerful immunosuppressant drugs. Doctors overcame the problem of rejection by taking her own stem cells to grow the replacement organ, using a donor trachea (lower windpipe) to provide the mechanical framework. Blood tests have shown no sign of rejection months after the surgery was complete. Speaking at a press conference in London last week, called to announce the results, Professor Martin Birchall, an ear, nose and throat surgeon from the University of Bristol who collaborated on the case, said: "This is just the beginning. I think it will completely transform the way we think about surgery. "In 20 years' time the commonest surgical operations will be regenerative procedures to replace organs and tissues damaged by disease with autologous [self-grown] tissues and organs from the laboratory. We are on the verge of a new age in surgical care." Professor Birchall said the technique could initially be extended to growing other hollow organs such as the bowel, bladder and reproductive tract but could later be extended to solid organs including the heart, liver and kidneys. "They have all got scaffolds [natural frameworks] on which new cells can be grown," he said. "We will need units next to hospitals to generate the cells. The trick is turning it into a therapy for thousands of patients - [the process] will have to be automated." Four teams of researchers collaborated on the case led by Professor Paolo Macchiarini of the Hospital Clinic and involving academic centres in Spain, Italy and the UK. The results are published in the online edition of The Lancet. — The Independent, London
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Technology for rural India
Whether industrialisation is a boon or bane is always a hot topic of debate but there is no doubt that industrialisation has given us un-counted benefits. But many who live particularly in villages of India in general and in villages of hills in particular are still looking towards scientists and engineers to apply their knowledge more for the eradication of their (village folk’s) hardships encountered in day-to-day life activities and thus make their lives more comfortable so that they should not think of diverting their trades for easy and green pastures.
Such processes look easy; in reality these are laborious and dangerous tasks and for performing all such activities skilled labourers are required. Skilled personnel are becoming scarce and farmers are finding it difficult to perform all such activities. These difficulties become worst in the absence of roads in the hills. No doubt such skills were acquired from childhood when a child was grown in the same environment and with the pace of time he used to learn all the tricks of the trades. But with the changing life scenario in villages also like children are busy in acquiring education for a good part of their childhood and could not spare enough time to acquire these skills. Moreover, even trained people are also being hurt or some times even loose their lives while doing these acts. |
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World’s longest sea bridge
China has scored on another front. By building a 36-km-long bridge across the East China Sea, it has captured the covetous title of the ‘Country with the longest sea bridge’!
Connecting the financial and commercial city of Shanghai with throbbing industrial city of Ningbo, the bridge, called Hangzhou Bay bridge, has cut the distance between the two cities by 120 km and the travel time by one and a half hours. Allowing a speed of 100 km/hr on the bridge and 120 km/hr on the land approaches, the bridge has halved the transit period between the two ports. Daily traffic volume is estimated as 50000 vehicles in the first year of its use. Built with part private funding, 30 per cent to be exact, the bridge is the first public infrastructure in China that has invited private funding. The bridge took less than five years for its completion. Cost of the bridge has come out to be Rs 850 crore. A unique feature of this project is that the time taken for its planning and design has been more than its construction period. The planning and design of the bridge took nine long years. More than 100 technical studies were carried out for it and 600 experts worked for these nine years to finally choose a design to assign a life of 100 years to the bridge. Once the design was frozen, in year 2003, the construction work took just five years—almost half the time taken by the bridge for its design and planning. The bridge faces a most complicated sea environment as one of three biggest tides on the earth occurs in this sea. It is called Qiantang river tide, a major tourist attraction and is one of China’s natural wonders. The tide waves rise as high as 25 feet and move at a speed of 25 to 30 km/hour. The area also falls under typhoon prone zone. That’s why the design of the bridge was considered as a major challenge by the bridge design engineers. Of its 36 km length, the bridge has its 32-km-long section spanning the sea. Technically, it is an S-shaped, cable stayed bridge as such a bridge can withstand high waves and multi-directional currents. Seismically, the bridge can withstand earthquakes having an intensity of 7 on the Richter Scale. Local seismic conditions have been taken into account. This two-way bridge in its 31.5 metre width has six lanes of 3.75 metres each that allow the vehicles to have a speed up to 100 km per hour. Built about 40 metres above the sea level, the bridge allows cargo vessels having 10000 tonne dead weight to navigate under it. More than 32 km length of cables has been used in its construction. During construction, major problems were posed by the pile driving and pier construction activities. A 10 km long trestle had to be temporarily erected for these activities. Pre-cast post-tensioned concrete box girders have been used in the construction of the bridge. During the bridge construction, eruption of natural gas was noted in one of the areas. Construction activities were stopped and gas exploration was undertaken. After exploring the distribution of the gas in the foundation area, its release was ensured to avoid any fire incidents or collapse of foundations before the piling work was undertaken. Methodology to erect structures in the sea is to pre-cast and pre-fabricate maximum possible components of the structure on the land, transport them to the sea and then erect them in position. Floating cranes and launching gantries are the major equipment used for erection of these components. Same procedure was adopted in the construction of this bridge also. High capacity vibratory pile drivers were another major equipment used for piling. GPS monitoring of the project was done throughout its construction period. |
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THIS UNIVERSE
We know that earth is rotating on its axis. What keeps it rotating on and on? Will it stop rotating some day just like a spinning top which loses its speed with time?
You must have found it that a rapidly moving thing goes on moving unless there is some thing to stop it. If a moving car loses its brakes the only way to stop it is to hit a sand bank or hit a wall. Through many observations of this kind Newton had formulated the law of inertia that a moving body would go on moving in a straight line till the time some force is used to stop it. What you have asked about rotation of the earth also applies to its revolution around the sun. No one is pushing it. It has been going for several crores of years. Recently India launched a mission to the moon. It completed its journey in several days because scientists decided to increase its speed in phases. Perhaps they wanted to make sure that they will arrive at the location of the moon just at the right time. They could have done it differently but they consciously chose this way in which the satellite made several circles of the earth. In this method they travelled lakhs of kilometres more than was absolutely. Some people thought they were needlessly wasting lot of rocket fuel. These people were all wrong. Once the satellite is in orbit it does not need any energy to go on moving. They decided, therefore, to keep checking everything as the satellite went around the earth about eight times. Or think of the moon. That is also a satellite of the earth and has been going around the earth for a very long time.So remember once you are made to move you will go on moving if there are no stopping forces. The top you referred to stops because of the frication of the air and the friction of the ground where the top is touching. If they were removed the top will also never stop.
Readers wanting to ask Prof Yash Pal a question can e-mail him at
palyash.pal@gmail.com |
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