31 May 2012

Century's last transit of Venus on June 6

Transit of Venus over the sun in 2004 - Wikimedia Commons

Transit of Venus over the sun in 2004 - Wikimedia Commons
In a rare celestial phenomenon that will occur only again on 2117, planet Venus will transit the sun during early morning of June 6 which will be visible from almost all over the world.
The transit of Venus lasting about five hours 40 minutes could be considered a mini eclipse of the sun, since the planet instead of the moon, will be covering 1/32 of the solar disc, M.P. Birla Planetarium director (research and academic) D.P. Duari said here on Friday.
"The greatest transit, when the black dot of Venus will be observed at the innermost point of the disc of the sun will occur at 7:02 am. The transit will end at around 10:20 am," Duari said.
He advised watchers to use scientifically tested Mylar filters or Nos 14 welder's glass and not to watch the event with the naked eye. It will be visible from eastern Australia, New Zealand, New Guinea, the Philippines, northern Asia, eastern China, Korea, Japan, islands of the western Pacific Ocean, Hawaii, Russia, Alaska and northwest Canada.
The concluding part of the transit will be visible in western Asia, including India, Europe, middle east and eastern Africa. It will be not visible from Portugal, Spain, western Africa and a portion of south eastern America.

Awareness camp for Venus' transit across Sun

A child looks at the moon through a telescope at an awareness program on the transit of the planet Venus across the sun on June 6 organised by the Breakthrough Science Society at the Marina Beach in Chennai on Sunday. Photo: R. Shivaji Rao
The Hindu A child looks at the moon through a telescope at an awareness program on the transit of the planet Venus across the sun on June 6 organised by the Breakthrough Science Society at the Marina Beach in Chennai on Sunday. Photo: R. Shivaji Rao
This rare astronomical event can be viewed without a telescope. The next transit will be visible only in 2117, followed by another opportunity in 2125.
The Breakthrough Society, a national organisation working towards popularising science, conducted an educational awareness program on the transit of Venus across the Sun to take place on June 6 at the Marina Beach in the city on Sunday. The event was organised to spread awareness of the historical and the scientific significance of the astronomical event.
At 3:30 a.m. on June 6, Venus will be seen as a black spot passing over the disk of the Sun and will complete its transit at 10:10 a.m. However, the planet passing across the Sun will be visible only past sunrise, at approximately 5:30a.m., in Chennai. This is one of the rare astronomical events that can be viewed without the aid of a telescope.
At the awareness campaign, members of the society distributed solar filters and gave out necessary precautions when viewing the transit of Venus. Telescopes were set up for the people to have a look at the craters on the moon and planets like Saturn and Mars.
Outlining the importance of this particular astronomical event as being the first international collaborative expedition, George Joseph, convener of the Breakthrough Science Society, said, “The timing of its entry and exit [out of the disk of the Sun] can help determine the distance between the Sun and the earth. It accounts as one astronomical unit.”
The last transit of Venus was in 2004. After this year, the next transit is expected to take place in 2117. Therefore, for the current generation, June 6, 2012, would be the last opportunity to witness this astronomical event.
Though most of the world would be able to view the transit of Venus, most of South America and the Western section of Africa would not be able to observe it. India would be able to see two-thirds of the event, though, given its size, would be different when viewed from different parts of the country.
Having conducted observation camps and programmes in schools and university, the Breakthrough Science Society hopes to bring people together at the Elliots beach on June 6 to witness the event through telecopes or solar filters.
A transit in astronomical terms is when one heavenly body passes in front of another such that, as viewed from Earth, we can see one move across the other in the background. The moon transiting in front of the sun during a solar eclipse, for example. Much more rare than a solar eclipse is the planet Venus transiting the Sun. The last time this took place was in 2004. But you are in luck! The next transit of Venus will occur this year! On June 5 to June 6, 2012 those positioned in the right spot on Earth, and with clear skies, will get to see this very rare event. The best spot to see the transit will be in the Pacific Ocean. The island of Tahiti is ideal for those who wish to travel to see it happen and the island is making preparations for many “astronomy tourists” to go there to view the transit. Portions of the transit will be viewable from Europe and North America. Most of South America and western Africa will not be able to see the transit. What an observer will see is a small black dot (Venus) passing in front of the sun. Depending on where you are on Earth to view the transit, you may see the dot move slowly across the Sun for several hours.
Sequences of transits occur in a pattern that repeats every 243 years, with transits occurring eight years apart followed by a gap of 121.5 years, then a gap of eight years (the 2012 transit finishes the latest eight year period from the transit of 2004) and then another long gap of 105.5 years until the next transit. So for those who miss the Venus transit this June, you will have to live to be very old indeed to catch the next pair of transits (2117 and 2125). To see if you can view part or all of the 2012 Venus transit go here (warning – may need fast internet connection).

First Historical Observations
Bird Flies During Transit Of Venus
As Galileo invented his first telescope in 1609 the first chance to observe a Venus transit using modern optical devices came with the transits of 1631 and 1639. Five years before the 1631 transit, in 1627, Johannes Kepler became the first person to predict a transit of Venus. Kepler successfully predicted the 1631 event. However, Kepler was unable to determine where would be the best location to observe the transit, nor did he realize that in 1631 the transit would not be observable in most of Europe. Therefore, no one made arrangements to travel to where they could see it, and this transit was missed.
Fortunately, 8 years later on December 4, 1639, a young amateur astronomer by the name of Jeremiah Horrocks became the first person in modern history to predict, observe, and record a Venus transit. Horrocks corrected Kepler’s earlier calculations and realized what we now know about Venus transits, that they occur eight years apart after long (very long) waits. It is commonly stated that he performed his observations from Carr House in Much Hoole, near Preston England. Horrocks also told his friend, another amateur astronomer by the name of William Crabtree, about the coming predicted transit and he also spotted the planet’s silhouette on the solar disk. Crabtree probably observed near Broughton, Manchester England. Although Horrocks was uncertain when the transit would begin, he was lucky enough to guess the time so that he was able to observe part of it. He used a telescope to shine the image onto a white card, thus safely observing the transit without harming his eyes. Using his observational data, Horrocks came up with the best calculation for an Astronomical Unit (AU).

Used to Calculate an Astronomical Unit

One hundred and twenty-two years later came the next eight-year pair of Venus transits. During that time the noted astronomer Edmond Halley (of Halley’s comet fame) had proposed that scientists could gain an accurate estimate of the distance between the Earth and the Sun (an Astronomical Unit or AU) using the scientific principal of parallax. Parallax is the difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. Halley correctly reasoned that if the Venus transit was viewed and measured from very distant points on the Earth, that the combined measurements, using parallax, could be used (with trigonometry) to calculate the actual distance between the Earth and the Sun (AU). Up to that time, the scientists were using Horrocks determination of AU, but realized they needed many more accurate observations to get a truer calculation.
Thus the Venus transits of 1761 and 1769 launched an unprecedented wave of scientific observations to the farthest points of the Globe. This was one of the earliest examples of international scientific collaboration. Getting (and surviving the trip) to these locations was as much an adventure as obtaining the first accurate data for a Venus transit. Scientists, mostly from England, France, and Austria, traveled to places as far apart as Newfoundland, South Africa, Norway, Siberia, and Madagascar. In South Africa very good measurements were obtained by Jeremiah Dixon and Charles Mason who would later go on to add their name to the historic Mason-Dixon Line in the USA. Noted points of the globe for the 1769 transit included Baja, Mexico; Saint Petersburg, Russia; Philadelphia Pennsylvania, USA; Hudson Bay, Canada; and from Tahiti, the great British explorer Captain Cook observed the transit from a place he called “Point Venus.”
Using the data obtained from the two transits, French astronomer Jérôme Lalande calculated the astronomical unit to have a value of 153 million kilometers. The calculation was a considerable improvement on Horrocks’ calculations from the 1639 observations. The modern measurement for an AU is 149 million kilometers (92,955,807.3 miles).

Discovery of the Atmosphere of Venus
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Prior to astronomers viewing the transit of Venus no one knew Venus had an atmosphere. All of that changed with the 1761 Venus transit. Looking from the Petersburg Observatory, Russian scientist Mikhail Lomonosov predicted the existence of an atmosphere on Venus. Lomonosov saw the image of Venus refracting solar rays while he observed the transit. During the initial phase of the transit, he saw a ring of light around the trailing end of the planet (the portion that had not yet transited in front of the sun). He correctly inferred the only thing to explain the light refraction would be an atmosphere around the planet.

Black Drop Effect
When observing the Venus transit, the most critical times are the first, second, third, and fourth contact. Being able to clearly see and time these transitions – from the shadow of Venus not touching, to just first touching the suns disc (first contact) the time the shadow of Venus fully transits into the disc of the Sun (second contact), and then when exiting, the point where the leading edge of the shadow of Venus again touches off the disc of the Sun (third contact), back into outer space, and the time the entire shadow has left the disc of the Sun (fourth contact) and is no longer visible – is important to gain accurate data. Unfortunately, an optical phenomenon called the black drop effect makes it difficult to see the second and third contacts.
Just after second contact, and again just before third contact during the transit, a small black “teardrop” appears to connect Venus’ disk to the limb of the Sun, making it impossible to accurately time the exact moment of second or third contact. This negative impact on the timing of the second and third contact contributed to the error in calculation of the true value of AU, in 1761 and 1769 transits. It was first thought the black drop effect was caused by the thick atmosphere of Venus, but it is now believed it is caused mostly by interference in the Earth’s atmosphere. Today, better telescopes and optics are minimizing the black drop effect for astronomers observing Venus (and Mercury) transits.

Search for Extrasolar Planets
By the time the 2004 and 2012 Venus transits rolled around, measurements of AU could be made using other and more accurate measuring techniques. However, that did not mean the 2004 and 2012 transits were not highly anticipated. They could still be used to do very important science, in this case, helping in the search for planets outside our solar system.
Scientists were eager to learn more about how patterns of light were dimmed and interfered with as Venus blocked out the Sun’s light. This would provide data to develop new and better methods to use the same technique to look for planets orbiting distant suns. Right now, a variety of other methods are used to “see” extrasolar planets orbiting distant suns. But most of these methods require the extrasolar planets to be very large – Jupiter-sized planets. Perfecting a way to “see” an extrasolar planet based on the light it blocks, coming from its sun, when it transits, would be a much more accurate way to detect the planet and could be used to ‘see” and calculate the size of much smaller planets orbiting these suns. However, extremely precise measurement is needed: for example, the transit of Venus causes the Sun’s light to drop by a mere 0.001 magnitude, and the dimming produced by small extrasolar planets will be much less.

First Transit of Venus “Movie”
In December 1882, astronomer David Peck Todd traveled from Amherst College in Massachusetts to California to photograph the transit of Venus. The transits of 1874 and 1882 were the first since the invention of photography so Todd’s documentation of the Venus transit was one of the first made using photographs. On top of Mount Hamilton from what would become Lick Observatory (still under construction in 1882), Todd collected a series of photographs during the December 6 transit. Viewing conditions were ideal with no clouds and he collected 147 glass negative plates documenting most of the transit. The plates were carefully stored but soon forgotten as astronomers found better ways to view and document the transits.
In 2002, two astronomers writing for Sky and Telescope magazine rediscovered the long forgotten plates, all of them intact and in good condition. They realized the sequence of photos could be made into the first “motion picture” of a Venus transit. The resulting “movie” documents one of the historic observations of a Venus transit. You can see the animation of the transit made using the 147 negatives here (warning – you need QuickTime and a fast internet connection).

Transit Creep and Non-Pairing Transits
Seipha Vt2004
The months in which we can see the eight-year pairings of Venus transits is “creeping” forward. Before the 1631 transit, the pair occurred in May and November. Transits can currently occur only in June or December. Transits usually occur in pairs, on nearly the same date eight years apart. This is because the length of eight Earth years is almost the same as 13 years on Venus, so every eight years the planets are in roughly the same relative positions. However the small difference means the timing of the arrival of the eight-year pairs of transits is slowly creeping forward on the Earth calendar.
This approximate conjunction between Earth and Venus usually results in a pair of transits, but not always. The transit of 1396 did not have a pair (there was no transit in 1404, one did not appear until May 1518). The next “solo transit” will be in 3089.

Multiple Transits at Once
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Multiple transits are very, very, very rare occurrences, but do happen. It is possible for there to be a solar eclipse and a transit of Venus at the same time. The last time this took place was in the year 15,607 BC. The next solar eclipse plus Venus transit will occur on April 5, 15,232.
It is also possible for Mercury and Venus to transit the Sun at the same time. That’s right, both of Earth’s inner planetary neighbors perfectly lining up with the Earth’s orbit and the Sun so that an observer on Earth could see both tiny shadows passing in front of our Sun at the same time. The last time this happened was in the year 373,173 BC. The next time the simultaneous transit of the Sun by both planets will occur will be July 26, 69,163. Will man even be around to see this far off transit?

Transit of Venus March

The year 1882 was a Venus transit year and to commemorate this historic event, and the unveiling of a statue of American physicist Joseph Henry (who developed the first electric motor and was the first secretary for the Smithsonian Institute), the famous bandleader and composer John Philips Sousa was commissioned to write a march. Sousa wrote the march, it was published by the J.W. Pepper Company, and quickly forgotten about and lost. But not before the march was performed for the first time on April 19, 1883 at 4pm, which, for Sousa, a Freemason, had Masonic significance having to do with the element copper, copper used in electric motors (invented by Henry), and Venus, which probably makes perfect sense to Masons reading this list but is lost on the author.
In any event, the march came and went about as fast as a Venus transit and was thought lost for over 100 years until it was rediscovered in the Library of Congress in… wait for it… 2003! Yes, one year before the 2004 transit the long lost Sousa march “Transit of Venus March” was found just in time to celebrate the next transit! In 2004 the Library of Congress joined with NASA to bring back the long lost march to the general public (who, apparently, were as thrilled with it as the people of 1883). Now you too can hear Sousa’s Transit of Venus March (which to me sounds just about the same as all his other marches) in the clip above.

Guillaume Le Gentil
Guillaume Le Gentil
A French scientist and astronomer who took long names to a new extreme – Guillaume Joseph Hyacinthe Jean-Baptiste Le Gentil de la Galaisière (Guillaume Le Gentil) made some important contributions to astronomy, especially some of the first observations of several Messier objects. But it was his role as part of the international drive to document the 1761 Venus transit that makes him such an interesting and tragic figure.
Le Gentil was one of over a hundred observers from around the world who marched or sailed off to far away locations of the globe so as to gain various far flung vantage points of the transit to help calculate a more accurate determination of an AU. Not all of these expeditions met with success, in fact, many were thwarted by cloudy skies, rain, unfriendly natives, difficulty getting to where they wanted to go, and faulty equipment. But no one was as unlucky as Le Gentil.
Guillaume le Gentil set out from Paris in March 1760 bound for Pondicherry, a French colony in India. He reached Mauritius in July. But by then he learned that France and Britain were at war. Before his ship arrived, he learned the British had occupied Pondicherry so the ship diverted back to Mauritius.
On June 6, 1761 the transit arrived as predicted, but Le Gentil was still on board the ship. Though the skies were clear he could not make observations aboard the rolling deck of a ship at sea. No problem, he thought, I came this far, I will wait for the next transit, eight years away.
He passed the time, among other ventures, mapping the coast of Madagascar and then set off or Manila in the Philippines to see the 1769 transit. Once there however he was met with resistance from the Spanish authorities. So he set sail once again for Pondicherry India. He arrived in March 1768 and built a small observatory and waited. June 4, 1769 finally arrived and though previous weeks had offered perfect clear skies, June 4th had nothing but clouds and rain. He saw nothing. Despondent, he decided to return to France. He was delayed by an attack of dysentery and then his ship was caught in a storm. He was dropped off at the small island of Reunion, east of Madagascar, and he had to wait until a Spanish ship could bring him back to France. He arrived in France almost 11 years after he left, in 1771, only to find he had been declared dead, removed from his position in the Royal Academy of Sciences, and stripped of his fortune by his greedy relatives. Oh yes, his wife had remarried as well. Eventually his position to the Academy was restored and he lived out the remainder of his life in France.

Transit of Venus next week

30 May 2012 by Editor | Filed in People 'n Issues Transit of Venus next week
On June 5, 2012, 22:09 UT, the Sun, Venus and the Earth will be in alignment and observers on Earth where the Sun is visible at this time will view a “Transit of Venus,” a rare occurrence as only seven transits have occurred since the invention of the telescope.

An astronomical transit occurs when a smaller closer celestial object passes across the face (disc) of a larger more distant celestial object. In this case, the time taken for Venus to transit the Sun will be six hours and forty minutes. Viewed from Earth, transits of the Sun can only occur with inner planets, those that have an orbit closer to the Sun than ours, namely, Mercury and Venus. In order to see the transit, the Earth, transiting planet and Sun have to be aligned. Transits of Venus across the Sun are extremely rare, in fact, only seven such events have occurred since the invention of the telescope (1631, 1639, 1761, 1769, 1874, 1882, 2004). This event will be the first transit while there is a spacecraft orbiting that planet – ESA’s Venus Express.

Transits of Venus are only possible during early December and early June when Venus's orbit crosses the plane of the ecliptic (the plane of the Earth’s orbit around the Sun). If the Sun, Venus and Earth form a straight line when this occurs (termed inferior conjunction) a transit will occur. Venus transits occur at intervals of 8, 121.5, 8 and 105.5 years. The last Venus transit was in 2004, eight years ago, and so unfortunately the next transit will not occur within our lifetime. The next two are predicted to occur on December 11, 2117 and December 8, 2125!

Unfortunately, the transit will not be visible from South Africa as it occurs between 00:09 and 06:49 local time on June 6 (6 hours 40 minutes in total). However, if we were able to see the transit what could we expect?

Astronomers describe the four main phases of a transit as follows:
  1.  Ingress, exterior (or first contact): the point at which Venus’ disc just touches the outer edge of the Sun. Shortly after, the planet appears to make a small black indent on the solar disc.
  2.  Ingress, interior (or second contact): the point at which the entire planet has just moved into the solar disc.
  3.  Egress, interior (or third contact): the point at which the planet touches the opposite solar limb.
  4.  Egress, exterior (or fourth contact): the point at which Venus is just outside the Sun’s disc, concluding the transit.

The “Greatest transit” is the instant at which Venus is in the middle of its path across the solar disc, this marks the halfway point in the timing of the transit.

Figure 1: Image from 
http://eclipse.gsfc.nasa.gov/OH/transit12.html This diagram shows the path that Venus will take across the Sun on  June 6 (as well as the path it took in 2004). The four contact points are marked along with the point of greatest transit. The numbers on the scale give the time (UT) at which Venus is at a particular location as it crosses the Sun.

The times for each of the contact points for the June transit are shown in Figure 1. Note that these times are for an observer at Earth's centre. The actual contact times for any given observer may differ by up to ±7 minutes. This is due to effects of parallax, as Venus's 58 arc-second diameter disc may be shifted by up to 30 arc-seconds from its geocentric (Earth centred) coordinates depending on the observer's exact position on the surface of the Earth. During the 2012 transit, Venus's minimum separation from the centre of Sun will be 554 arc-seconds, it will not pass across the centre of the Sun but rather to the North of centre.

Figure 2 shows the global visibility of the Transit of Venus of 2012. The un-shaded region shows where the entire transit is visible. The grey shaded region indicates where no part of the transit is visible and the blue and green shaded regions indicate where only part of the transit will be visible (Sun setting and rising respectively). Taken from 
http://eclipse.gsfc.nasa.gov/OH/ transit12.html

Although not visible from South Africa, the entire transit will be visible from north western Canada, Alaska, the western Pacific, northern Asia, eastern Australia, and New Zealand. The Sun sets while the transit is still in progress from most of North America and northwest South America. Similarly, the transit is already in progress at sunrise for observers in central Asia, Europe, the Middle East and eastern Africa. No portion of the transit will be visible from western Africa, and much of South America. Note that due to the International Date Line the Western Hemisphere will see the transit on June 5.

How to observe a Transit
As the apparent diameter of Venus is nearly 1 arc-minute, it is just possible to see Venus crossing the Sun without a telescope. Note that special solar filter protection is required, never look directly at Sun with or without sunglasses, it can cause blindness. However, as the planet’s angular size is only 1/32 of the Sun's apparent diameter, using binoculars or a small telescope will make the transit much clearer. All binoculars and telescopes must be equipped with adequate filters to ensure safe solar viewing. In fact, the safest way to watch the transit using a telescope is to project the image of the Sun onto a piece of card behind the telescope’s eyepiece. 

White light observations of contacts I and IV are not technically possible, since Venus is only visible once it has entered the solar disc. However, if a Hydrogen-Alpha filter is used, it is possible to see the planet against either solar prominences or the solar chromosphere before and after contacts I and IV. Observations of contacts II and III also require magnification to see clearly.

Just before contact II, the “black drop” effect is seen. Here, Venus appears attached to the limb of the Sun by a thin thread, forming a small black teardrop shape. This occurs as it fully enters the solar disc just after contact II and just before contact III as it begins to leave. The black drop is thought to be an optical effect caused by the effect of observing through Earth’s atmosphere, combined with diffraction of light inside the telescope, and by the dimming of the intensity of the Sun’s surface just inside its apparent outer edge. Atmospheric seeing and the black drop effect often make it difficult to measure contact timings to accuracies better than several seconds.

Live webcast
Many observatories around the world will be the streaming the event live across the internet. Some URLS are provided below:-


www.rssd.esa.int/index.php?project=VENUSEXPRESS&page=venus_transit - which shows images in both H-alpha and white light.


The history of Transits and their uses in Astronomy 

Sir. Edmond Halley first realised that transits of Venus could be used to measure the Sun's distance. The technique relied on comparing observations made from around the world. By timing how long it took for Venus to cross the solar disc from different locations on Earth, one could work out the path the planet appeared to take across the Sun’s disc from different locations. These straight lines, or “chords” are parallel to each other, but not exactly overlaying because of parallax effects. By measuring the angle of parallax, or the perpendicular distance between the two parallel paths and knowing the distance between the two observers on Earth it was possible to calculate the distance to Venus using trigonometry. From this, the distance to the Sun could be calculated it was known (from Kepler’s 3rd Law of planetary motion) that the ratio of the Venus-Sun and Earth-Sun distance was 0.72. (Or that the distance to Venus is 0.28 times the distance to the Sun). Venus transits were considered better suited to this goal than Mercury transits because Venus is closer to Earth and consequently exhibits a larger parallax.

Halley challenged future generations to organise major expeditions in order to observe the transits of 1761 and 1769. Unfortunately, his method proved impractical since contact timings of the desired accuracy were impossible due to the effects of atmospheric seeing and diffraction (the black drop effect mentioned earlier). However, observations of the 1761 and 1769 transits of Venus gave astronomers their first good estimate for the Sun's distance.

Undeterred, another major observing campaign was mounted by many nations for the Venus transits of 1874 and 1882. Indeed, the Cape Astronomer Royal from 1879 to 1907, Sir. David Gill mounted an expedition to Mauritius to observe the 1874 Venus transit, and later when employed at the Royal Observatory, Cape of Good Hope (now home to the South African Astronomical Observatory). He conducted observations of the 1882 Venus transit at the observatory grounds in Cape Town. Additionally, a British Transit of Venus expedition was sent to Touwsriver, and an American expedition was sent to Wellington to observe the 1882 transit. Gill’s measurement of the distance to the Sun was accepted as the most accurate at that time. The distance to the Sun and planets can now be measured extremely accurately using radar.

During the transit of 1761 astronomers noticed a halo of light around the planet’s circumference during ingress and egress, this is known as an aureola. This provided the first proof, that Venus has an atmosphere as the effect is caused by refraction of sunlight in the dense upper atmosphere of Venus. We now know Venus has an inhospitable dense atmosphere of carbon dioxide and nitrogen with clouds of sulphuric acid.

Today, transit events are used to detect and study exoplanets, planets orbiting stars other than our Sun. As a planet passes in front of a star, it temporarily blocks out a tiny portion of the starlight, not only revealing its presence, but also providing clues about the planet’s size. Transits are also being used to search for exoplanets that may harbour life. If a planet has an atmosphere, a small fraction of the light from the star will pass through the atmosphere and reveal its properties, such as its chemical composition, including the presence of water.

The Sun Earth Moon System (SEMS) team is doing a live webcast of the venus transit from Anchorage, Alaska. You can view it here: http://www.sems.und.edu

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27 May 2012

Tree census narrates stories of living monuments

Asha Sridhar
The Baobab tree on the premises of the Government Museum, Egmore — Photo: Maheshwar Singh
THE HINDU The Baobab tree on the premises of the Government Museum, Egmore — Photo: Maheshwar Singh
A weary group, after travelling through time, and browsing through sculptures and inscriptions at the Government Museum, Egmore, sluggishly laid out a straw mat and broke for lunch under the shade of a living monument— a century-old mango tree.

Rarest and the oldest

The Museum, which has some of the rarest and oldest trees in the city, will soon publish the findings of a tree census that was conducted on its campus in February this year, said a department official.
“More than 80 genera have been identified and we are currently classifying them into various categories such as ornamental trees, avenue trees, trees of economical value, and such. It will take a month or two,” said the official. The campus is said to be home to more than 500 trees.
The tree census, conducted in February in the museum, was part of the larger tree census project undertaken by the Urban Forestry Division, Chennai Circle, of the Tamil Nadu Forest Department. The census at the museum was organised in collaboration with the co-ordinator of the project, Dr. D. Narasimhan and saw 35 students from Women's Christian College and Presidency College taking part. The students measured the height and girth of the trees, identified the landmarks nearby, and also recorded remarks.
“Trees like Limonia acidissima , Polyalthia longifolia, Thespesia populnea, Mangifera indica, Ficus bengalensis, Guazuma tomentosa, Borassus flabellifer, Citrus, and Eucalyptus were covered,” said Project Co-ordinator, M.N. Pushpa, Curator, Botany Section of the museum.
Parks and garden areas near the National Arts Gallery, the pond area of the Museum, the Main Block, the Centenary Exhibition Hall, and the Front Building were among those covered by the project. “Around 100 trees around the pond area, 110 trees around the Museum Theatre, and 200 trees near the Front Building and the National Art Gallery were identified,” she added.
The rare trees at the museum, according to Pushpa, include the Swietenia mahogany, and the canon ball tree, which are also some of the oldest.

Centre of attraction

And one of the trees that attracts the attention of many passers-by, she said, was the fishtail palm. The boards, which have been put up by the Botany section on the trees, also provide information about the vernacular names of the trees.
“The Adansonia digitata or the Baobab, has a girth of 7.5 metres and is 12 metres tall,” she said, sounding a little astonished herself. This is said to be one of the oldest Baobab trees in the city today.

Kidney, the amazing organ

Dr. N. Mohandas
Students on a kidney disease awareness walk in Coimbatore. File Photo: M. Periasamy
Students on a kidney disease awareness walk in Coimbatore. File Photo: M. Periasamy
Kidney Day is observed all over the world on the second Thursday of March every year. Incidence of kidney failure cases is increasing day by day due to a steep increase in the number of diabetes and hypertensive patients in the recent past. Globally, nearly 50 million people suffer from renal failure but only 1 million among them undergo treatment. It has been estimated that 360 million people will die of renal failure in 2015.
Though there are no accurate statistics on the subject, the available data shows that 7.58 million people in India are suffering from kidney failure. Surveys conducted point out that less than 5%of the general public is aware of the location and functions of the kidney.
It was to create awareness among the people that Joel Kopple, the founder of International Federation of Kidney Foundations (IFKF), conceived the idea of World Kidney Day (WKD) in the year 2003. The day offers a crucial and visible opportunity to educate policymakers as well as the general public including all those who are at the risk of kidney disease/failure.
The kidney does a magnificent job in our urological system, thus becoming a unique organ in the body. Every day, it filters 200 litres of blood. It is an amazing organ not only excreting urine from the blood, but also maintaining the body electrolyte, maintaining blood pH, synthesises active form of vitD3. It produces Erythroprotien, which is essential for maturation of the red blood corpuscles and to maintain the blood pressure.
Then why does the kidney fail? It can fail due to uncontrolled hypertension, diabetes, failure to take proper treatment for the nephritic syndrome (excess protein in the urine), prolonged obstruction in the urinary tract, frequent use of analgesic (pain-killers) tablets, use of native medicine made of the metals, and a family history of renal disease. Some do suffer from kidney failure, without any specific or identifiable cause. Various reports from Sri Lankan studies reveal that environmental factors like the use of pesticides, use of medicines containing metals, hydrocarbon, etc., too can cause kidney failure.
Chronic kidney failure causes severe economic burden to the individual and his family, and to the nation as a whole on dialysis and renal transplantation. Such patients undergo a lot of stress and strain for want of a potential donor for transplant, most often resulting in depression. With frequent rackets and malpractices involving kidney donation which have become common, in spite of the strict enforcement of rules, the motivation of brain-death patients for organ donation is the only alternative for transplantation.
Prevention is always better than cure. In order to prevent kidney failures, it is essential that everyone knows about the kidney and its importance. There are eight golden rules which help to avoid kidney failures.
1. Keep fit and active. Maintain ideal body weight.
2. Keep regular control of blood sugar.
3. Monitor your blood pressure.
4. Eat healthy and keep your weight in check.
5. Maintain a healthy fluid intake.
6. Do not smoke.
7. Do not take over-the-counter pills regularly.
8. Check your kidneys function if you have any one or more of the high risk factors. The theme for the this year's World Kidney Day (March 8) was: “DONATE — RECEIVE — KIDNEYS FOR LIFE”
(The writer is retired Professor of Nephrology, Thanjavur Medical College, Thanjavur, Tamil Nadu. His email is mohandas562@gmail.com)

15 May 2012

Take a chill fill

A. Shrikumar

Watermelon are ideal snack options on a hot summer's day. Photo: A. Shrikumar
Watermelon are ideal snack options on a hot summer's day. Photo: A. Shrikumar
It's that time of the year when the mercury soars. Going out in the scorching sun can leave you drained and it is vital to maintain body hydration. Apart from the regular intake of water, doctors recommend natural fruit juices and drinks. They are quick quenchers with ample nutrients and are better than aerated soft drinks with chemical preservatives and artificial flavours. A. Shrikumar looks into the nutritional value and health benefits of some of them.
Palmyra Fruit (Nongu) and Pathaneer
Pathaneer and nongu are fast catching up with the city people. Many kiosks, including government-run ones, have sprung up along the main roads. It tastes good and is light on the pocket.
Nutritional value: Kal nongus (ripe fruits) and pathaneer are rich in carbohydrate and moisture content. They provide plenty of minerals such as calcium, phosphorous and iron, along with fibres and proteins to the body. The fruit contains Vitamins A, B and C in the form of ascorbic acid. It is perfect for the figure-conscious as it contains zero fat.
Health benefits: The pulp is highly nutritious and the fibrous outer layer mitigates body heat. Application of pathaneer on the body cures boils, rashes and dermatitis.
Best known as the base of salads, cucumber helps you instantly regain lost energy. It is also a great snack.
Nutritional value: Cucumber has 96 per cent water that is more nutritious than regular water. Its low calorie content makes it an ideal diet for people looking to lose weight. Vitamins such as thiamine, riboflavin, niacin and Vit.B9, calcium, magnesium, phosphorous, potassium, zinc and iron are the major constituents.
Health benefits: Extremely helpful in keeping the body hydrated and regulating body temperature. It also helps in flushing out toxins, controls blood pressure, is beneficial for teeth and gums, promotes joint health, and stimulates hair and nail growth.
The juicy, red slices of watermelon are ideal snack options on a hot summer's day.
Nutritional value: A wide range of minerals like fluoride, iron, sodium, magnesium and potassium, optimum sugar and dietary fibres, and also traces of vital vitamins are present. These strengthen the immune system and keep infections at bay. Watermelon is also a concentrated source of carotenoids, which prevent the formation of cancer cells.
Health benefits: Rich in antioxidants, watermelons can neutralise free radicals in body and reduce the risk of colon cancer and heart attacks. It reduces airway spasms in asthma patients. Beta carotene in watermelon sharpens eyesight. Apart from regulating salt content in the blood, it also eases inflammations and prevents diabetes.
Tender coconut
One of the most easily available cooling options on the roadside, tender coconut tops the list. Though the price has increased, it continues to be the first pick on a hot day. Nutritional value: Both the flesh and water of tender coconut contain high moisture. Good amount of protein, fat, sugar, dietary fibre, potassium, iron and Vitamin C are also present, apart from the calories that can keep you brisk round the clock.
Health benefits: Keeps the body cool, kills intestinal worms, checks urinary infections, promotes growth, cures malnourishment and is effective in the treatment of kidney and urethral stones.
There's nothing like our good old home-made ‘mor' to beat the heat. Best served chilled in earthen pots with a hint of pudina, lemon, coriander leaves and cumin seeds, buttermilk definitely lifts your spirits on a hot day.
Nutritional value: Replete with the most absorbable form of Vitamin A, E and K, lauric acid and lecithin. It is also a vital source of the mineral selenium, has high anti-oxidant content and saturated fats, protein, calcium and iodine.
Health benefits: Primarily cures thyroid and adrenal problems, fungal infections, regulates cholesterol metabolism, protects arteries, boosts immunity and builds muscles. It also has strong anti-tumour and anti-cancer properties. Is a quick source of energy that promotes brain and nerve development and protects against gastrointestinal infections.
Expert Talk:
Dr. G.P. Rengarajan, Homeopathic Physician: “During summers, the need for glucose and water content in the body increases. Natural drinks go a long way in mitigating body heat and restoring salt balance. Moreover, drinking natural liquids cleanses the blood and eliminates toxins.”
C. Tharanya, Dietician, Talwalkars Better Value Fitness Centre: “For people who do heavy work, it is very important to drink water or fruit juices as it replenishes the carbohydrate content. A balanced diet plan should necessarily include natural drinks like buttermilk and lemon juices.”

Beat the fat

Parvathy Menon
DIETARY CHANGES: Vegetables help to keep one fit and healthy. It also helps in reducing weight. Photo: V. Ganesan
DIETARY CHANGES: Vegetables help to keep one fit and healthy. It also helps in reducing weight. Photo: V. Ganesan
Battling the bulge? It has its ups and downs, here is a plan that might help you lose some of those troublesome kilos
Losing weight may seem like an uphill task without some useful pointers. Weight loss is tied to not just physical, but also psychological and emotional health .
Here are some suggestions that might help you lose weight gradually and surely. You need to make lifestyle changes rather than extreme cuts in your diet.
Limit the sugar intake in your cuppa to one spoonful only. Decrease the sugar gradually, so your body does not miss it suddenly.
Cutting salt , like avoiding sweets, is a good idea. But you need a moderate amount of salt in your system.
Cutting carbohydrates completely may not be the best idea for vegetarians however, you can reduce the amount of cooked rice and concentrate more on the curry, like say a dal as the lentil is high on protein, and a healthy stir-fry.
While rice has simple carbohydrates that releases sugar within an hour, a whole wheat chapathi/ roti contains more complex carbs that score better in terms of G. I. load.
You can have a single papad at the most, because it is deep-fried.
Have five servings of fruits and vegetables a day, an apple, a mini banana, a cucumber, a carrot or a cup of grapes constituting a single serving.
You can also have small amounts of nuts, like almonds, but avoid cashews as they easily tend to fatten.
Drink about one-and-a-half litres of water a day as it detoxifies your body and helps in fat reduction. It is said that you must calculate your body weight and drink half the amount in ounces. For example, if you weigh 50 kg, ideally you would intake 25 ounces of water. Drinking lots of water is a must.
Choosing sprouts is another healthy option. You must not eat chickpeas in the raw form, it is said to be toxic, and might upset the stomach. The legumes must be soaked and cooked.
Have meals every two to three hours. This is a signal to your body that hey, food is coming, so the body will not store or accumulate it as fat.
Choose light snacks like a fruit, a vegetable, puffed rice, crudité (short eats) or plain popcorn. Consume a different, light snack daily.
It is advisable to avoid butter, instead, you can make some dish with a tablespoonful of ghee once in a while. Fats should not be cut totally as you need a little for the body to function smoothly.
Do not starve yourself, if you have cravings, its important to indulge in a small quantity. Portion control, in other words, is the key. For instance, for a birthday, you would stop at a single slice of chocolate cake.
It is important to walk for not less than 20 minutes daily. Ideally, use the treadmill for 30 minutes, starting with a speed of three for the first ten minutes, then moving to a brisk four. Importantly, you must not tax your body too much. The distance can be gradually increased from half a kilometre to a stage where you would clock five or six kms.
The thing to bear in mind is self-regulatory control when it comes to eating.
Avoid all chocolates, processed and bakery items.
Choose fresh fruits, vegetables, sprouts and leafy greens.
Cottage cheese (paneer) can be incorporated for the sake of protein. Cook your own meals, like say a healthy soup.
Keep active for an hour before tucking in at bedtime.
It is important to have regular and full meals and drink lots and lots of water in between. Performing household chores is not just that , but necessary activities, both psychologically as well as physically.
Here is a healthy recipe to get you started –
Green gram – 1 cup
Lemon juice – Of half a
Coriander leaves – 1-2
tbsp, chopped
Green chillies – 3-4,
Refined oil – 1 tbsp
Mustard seeds – 1 tsp
Dried red chillies – 2
Omam – A pinch
Asafoetida – A small
Salt – To taste
Sprout the green gram. Soak overnight. Change the water in intervals so all the toxic effects are gone. In a bowl, combine the green gram sprouts , the corianderleaves, lemon juice, salt and the green chillies. Warm the oil, let pop mustard, add red chillies, curry leaves, finally lower the flame and add a pinch of asafoetida and Omam (aimodakam.) Stir in the tempering. Finally, you can add some freshly grated coconut too.

Taste of summer

Sajini Sahadevan
A slice of joy Photo: M. Karunakaran
The Hindu A slice of joy Photo: M. Karunakaran
If the searing heat is taking its toll on you, it may be time to take stock of what you are eating
“This time, it's hotter than last year,” that's what everyone is saying these days. And this time, it is no exaggeration. Soaring temperatures are leading to cases of heat exhaustion – a rarity here. But don't let those television commercials fool you into buying fizzy drinks to quench your thirst. What you eat and drink need not always cool you.

Drink water

Liquids in the form of water and fresh juices trump everything else in extreme heat. Mini Mary Prakash, chief clinical dietician, PRS Hospital, adds that it would do good to up one's water intake from the usual two litres to anywhere between 3.5 and four litres: “Green tea is recommended instead of regular tea as it has less caffeine. Alcoholic beverages, chilled drinks, even iced tea won't help as they have a diuretic effect, leading to more loss of water from the body. Chilled drinks constrict the blood vessels and obstruct sweat.”
She also advises adding a few sprigs of mint to one's early morning cup of green tea. “That's no substitute for water,” says Jayasree N. S., senior dietician, KIMS. “One can drink up to 15 glasses of water every day.” She adds: “Coffee beyond the normal limit will only add to the heat as it contains caffeine. Chocolates also increases body heat,” says Jayasree.
Milk, that too low-fat, and curd, also in variations like buttermilk, are recommended as it also provides calcium. Tomato juice is also great for the weather as it provides lycopene. “Lycopene helps repair the body's tissues. Cucumber, musk melons or water melons are good too as they are high in water content.” Those looking to lose weight should skip the sugar when drinking juices. “It is good if those dieting do not substitute fruit juice for water as it can lead to weight gain,” says Mini.
Jayasree points out that people can help themselves best by avoiding foods with fat content: “Avoid snacking on puff pastries, cake, things of that sort as they will surely have fattening ingredients such as butter or ghee to help increase taste and texture. Fried food such as chips and puris should not be had either.”
Red meats are a strict no-no, while chicken and fish are still better, though again not fried. “Everything we have for a sadya is acceptable. As for vegetarians, it is important to keep having pulses.”
Mini says the summer is also the season when people tend to contract food-borne illnesses. “Vendors add ice to fruit juices. This may not always be hygienic. Yoghurt contains probiotic bacteria that decreases chances of food-borne infections. It should be made a part of one's daily diet.”
Save dry fruits like dates, figs and apricots for winter. “The absence of water in them will only make one thirsty. Also avoid sugary foods or anything with honey or molasses as they will make one thirsty and tired. Ice cream and beer, though summer favourites, have a temporary cooling effect on the body. Food that is too salty or spicy adds to the discomfort as they generate heat,” Mini says.
Both dieticians agree on the goodness of vegetarian food in summer. “Christians observe Lent in summer. It is a time when the community follows a vegetarian diet. This has health benefits too,” adds Mini.
For those who didn't know, Mini says cardamom, gooseberry, papaya, mushroom and pomegranate compromise ‘cooling' foods too. Mango, she adds, increases heat: “If you are really craving mangoes, put them in water overnight and then have them as it absorbs the heat.”
So now that you know, bring more of the right food into your diet to stay cool during summer.

Buttermilk, the best bet


DIET What could be more soothing than a chilled glass of buttermilk in summer? And it makes a great health drink too
The dog days are definitely here. And, just like a faithful dog, the searing heat and appalling humidity follow you everywhere, squeezing sweat from every pore, teasing your hair into a frizzy mess and making the collective mood crotchety. But, as if prickly heat and pongy toes weren't problem enough, there's that vexing trouble with most summer coolers — what's instantly refreshing, like ice cold water, is often also a prescription for a ghastly sore throat; packaged juice, on the other hand, is nourishing, but contains such vast quantities of sugar, that it's a short cut to disastrous weight gain. Frankly, you're left with few options… and not many are as safe a choice as buttermilk.

The perfect summer drink

Nimmi Ittycheria John, Nutritionist and Diet Consultant, says ancient Indian wisdom has always regarded buttermilk as a thirst quencher. “Affordability and easy availability make it the logical choice. And it scores over milk as it is a fermented form (of milk), rendering it easier to digest.”
It is this soothing, digestive property of buttermilk that makes it so popular in Suguna Mohan's household. “In summer, we prefer buttermilk over tea or coffee after breakfast,” she says. “I like to grind together green chilli, ginger, curry leaves with a little thick curd and then strain it with a sieve. I then add water, salt and asafoetida powder and top it off with ice cubes. When I have guests over, say, for a sumptuous lunch, I make a thicker version for curd rice, and they always ask for it to be served in a tumbler later!'
Octogenarian Kamala, who has been cooling off with buttermilk for several decades, says it's her preferred summer drink. “My doctor always advised me to drink plenty of it, to keep me from feeling tired. So I usually whisk up a large quantity of slightly watery buttermilk in the morning – adding fragrant curry leaves hand-crushed with rock salt and some asafoetida — and leave it on the dining table. It smells wonderful when I so much as open the lid; and whenever I felt thirsty, I have a drink; it really keeps me going.”
Its buttermilk's rejuvenating prowess that has made it so popular, especially in the ‘thaneer pandals' during temple festivals. Doled out from huge vessels, ‘neer more' (and its sweet cousin, ‘panagam') has people, particularly children, queuing up with beseeching eyes and 1-litre take-away bottles. And when the usual summer stomach bugs give you the runs, buttermilk is among the first things that's recommended to safely replenish fluids in the body.


“Buttermilk provides probiotics which are 'friendly' bacteria that help in maintaining beneficial bacteria in the intestines and warding away disease — causing microbes, therefore improving immunity. It is lower in fat and calories and higher on water than both milk and yoghurt. This makes it advantageous while weight watching and in replacing lost body fluids especially while convalescing,” says Nimmi.
But in Sheena's case, it was a simple case of having a ‘Thenali Raman cat' (allegedly scalded by hot milk and going off it for life) on her hands that made her turn to buttermilk. “Until she turned 6, my daughter fussed no end to drink her milk and used to run a mile when it was milk time. I was really at my wits end, as I was very worried about calcium deficit in the growing years. It was during a trip abroad that we found the answer to the problem — yoghurt drinks. My daughter loved the mild sweet and sour tang, and the interesting fruit flavours. When we got back, I got her started on buttermilk laced with salt and spices, south Indian style; and thankfully, she loved the savoury flavours too! It's also very handy to cart around, as it doesn't easily go ‘off' in the heat like milk.”
Nimmi Ittycheria John, Nutritionist and Diet Consultant on buttermilk…
* The precise nutritional value of buttermilk depends on how much yoghurt is used to make it. Typically one-fourth to three-fourths cup of yoghurt is beaten up with water. The more the yoghurt, the higher its nutrient density.
* Buttermilk has traces of protein, calcium, phosphorus and B Vitamins but more significantly, it provides probiotics which are 'friendly' bacteria.
* Buttermilk is best had as a filler and/or thirst quencher between meals and as digestive at the end of an elaborate meal.
* The flavouring ingredients used around the country such as asafoetida, cumin, coriander leaves, ginger, black salt, small onions, curry leaves and sea salt further enhance its digestive, carminative and curative properties.

Let's go birding

Soaring: The Brahminy kite. Photo: The Nature Trust
Soaring: The Brahminy kite. Photo: The Nature Trust
Take time off to look at the birds. Try to identify them and get to know their habits.
It's blazing hot, the migratory birds who left their countries to escape the harsh winter, realise that it's time to return home due to their internal clocks. Some who came in late, like the Plovers, have overstayed but will leave shortly. But then who is here to brave the summer heat? It's just the local lot. Most of them now are in breeding plumage. Their ordinary colours have vanished and now they are “dressed” in bright colours. Check on the normally white cattle egrets and pond herons, now clad in a different hue. The cattle egret builds nests near water bodies and does not mind socialising with other wading birds. Their nest looks like a platform of sticks and they are built on trees or shrubs. Cattle egrets are commonly seen in wetlands and rice fields. They accompany cattle, and pick insects off the larger animals. Some populations of the Cattle Egret are migratory and others show post-breeding dispersal.
The pond heron appears to have a hunched look because of its short neck. It has a short thick bill and buff-brown back. During summer, the adult birds have long neck feathers. When they fly, the white of their wings makes them stand out, instead of the usual dull look.
There are more ground nesting birds in bright colourful plumage, like the kingfisher, the red wattled lapwing and the tree pie amongst others.
Did you know that there are 90 varieties of kingfishers around the world? They prefer to perch on a high branch as it gives them momentum to dive deep into the water to get their prey. They are known as “cavity nesters”, making their nests in holes dug in the ground. These holes are usually in banks on the sides of rivers, lakes or ditches. Some nests are a small chamber at the end of a tunnel in a termite hill.
Don't miss out on the mynahs, the shrikes and the pied bushchat. Shrikes catch small insects and impale them on thorns. This is more convenient for them to tear it into small pieces and it is a kind of a “store house” so that they can return to it later.
While watching the birds, it's interesting to note their behaviour too, especially as it's the time for nest building and most of the juniors have arrived. The parents can be seen, taking turns to bring in the food for the chicks and feeding them. Their protection of the chicks would put any security service to shame, judging by their vigilance around the nest. They have sharp alarm calls.
The birds are also masters of camouflage. The red wattled lapwing would build its nest between three or four stones and lay its eggs. Plenty of grass is inlaid so that the eggs are not discovered. Another clever tactic would be to distract intruders by flying around a spot away from the actual nest. The red-wattled lapwing has a peculiar alarm cry “Did he do it?” Some of the local names are titeeri (Hindi), titodi (Gujarati), yennappa chitawa (Telugu) and aal-kaati (Tamil, meaning “human indicator”). The wetland birds too can be seen with their young, like the glossy ibis, the open bill storks, the pelicans, the Indian moorhens, the peasant-tailed jacanas, the purple herons and the coots.
It is commonly thought that birds vanish during summer as there is less water. But for the birds, when there is less water, it is easy for them to get their prey. This is especially seen in flamingos. When the waters go down, around 2000 of them “congregate” at the Pulicat Lake, near Chennai.
So set out this summer to spot those birds.
Some tips
Begin at home. Watch your home garden or the trees around your place. Check out the parks for birds.
Keep a bird feeder and water baths for them. Or scatter some grain.
Observe the birds that visit you. Take pictures and make notes of their appearance and behaviour. Check it out with a bird guide.
When you visit bird sanctuaries, the best time for bird spotting would be early morning or the roosting time t around 4.30 – 6.30pm.
Go about silently, do not disturb the birds or point at them, This would scare them off. When you want to take photographs keep them in your view, but slide up slowly to do it, from behind bushes or trees.
Listen to their different calls, and record them so that you can identify them later.
Mr. Thirunaranan, The Nature Trust. He has been “birding” for many years.

2 May 2012

“Timely action will save stroke victims”

Special Correspondent
‘Administration of an injection within three hours it would be possible to restore the patient's mobility”
Timely action will minimise the impact of stroke, ‘brain attack,' and with the administration of an injection within three hours it would be possible to restore the patient's mobility. This was the message conveyed to doctors drawn from various places of southern districts at a workshop on stroke prevention and management organised at the Apollo Speciality Hospitals here on Friday.
S. Meenakshi Sundaram, senior neurologist of the hospital, spoke about four vital factors, FAST, to determine whether a patient had suffered a stroke. He explained to reporters on the sidelines of the workshop that a drooping face was an indicator of stroke.
If one of the arms was numb or the person experienced difficulty in raising both the hands up together, he should be shifted to a hospital. The third factor was slurred speech. The person should be asked to repeat a simple sentence to identify slur. Time was a very important factor in saving the brain and hence the patient should be shifted to hospital as early as possible.
An injection of tissue plasminogen activator (tPA) administered within three hours of the onset of stroke would help regain lost faculties, he said. Karthik of Department of Neurosciences said that the patient could be discharged in about three days, if the injection was administered. Though costly, the injection would bring down the medical expenses of stroke treatment considerably, he claimed.
The workshop included interactive lectures and drill.

People more likely to eat fruits within reach


Greater visibility of fruit increases their intake, according to a new study. Photo: Mohammed Yousuf
The Hindu Greater visibility of fruit increases their intake, according to a new study. Photo: Mohammed Yousuf
Want to stay healthy - then place fruits in a clear bowl within arm’s reach, so that you could help yourself whenever you felt the urge to eat.
The new study says that when fruits are within reach, people are more likely to eat them. Greater visibility of fruit increases their intake, but the same does not hold true for vegetables.
Researchers Gregory J. Privitera and Heather E. Creary, both from St. Bonaventure University, Olean, U.S., tested a total of 96 college students by placing apple slices and carrot cuts in either clear or opaque bowls at a table close at arms’ length or at a table two metres away.
Participants watched as the food was taken out of its packaging and were told that they were welcome to eat it, the journal Environment and Behaviour reports.
After leaving the students alone with the food for 10 minutes, the researchers found that when apples and carrots were left close to the participants, those healthy foods were more likely to be eaten, according to St. Bonaventure statement.
Interestingly, making the food more visible to participants by placing them in clear bowls increased the intake of the apples but not the carrots. The researchers said this might be due to the fact that fruit is sweeter and may induce more motivation to eat than bitter-tasting vegetables.
“Apples, but not carrots, have sugar, which is known to stimulate brain reward regions that induce a ‘wanting’ for foods that contain sugar,” the authors wrote. “Hence, apple slices may be more visually appealing than carrots.”

Bt Brinjal poses a risk to health, environment: Greenpeace report

Special Correspondent

‘Spread of the Bt gene could make the brinjal a problematic weed'
An independent enquiry has revealed that the cultivation of genetically engineered (GE, also called genetically modified, or GM) Bt brinjal poses risks to the environment and possibly to human health. The occurrence of wild, weedy and also cultivated relatives presents a likelihood that the GE Bt gene will spread to these relatives but, so far, this has largely been overlooked in the risk assessments for GE Bt brinjal, it says.
Genetically engineered Bt brinjal and the implications for plant biodiversity – revisited, an independent study commissioned by Greenpeace International, finds that brinjal relatives do occur in the regions where cultivation of GE Bt brinjal is proposed, and that GE Bt brinjal may mate with these relatives to spread the GE Bt gene. Spread of the GE Bt gene would have considerable ecological implications, as well as implications for future crop contamination and farmers' rights.
Importantly, the spread of the GE Bt gene could result in the brinjal becoming an aggressive and problematic weed, the Greenpeace report suggests, while impressing upon the governments the need to employ the precautionary principle and not permit any authorisation of the outdoor cultivation of GE Bt brinjal, including field trials
The cultivation of GE Bt brinjal is proposed in some countries across Asia, including India, where there is currently a moratorium on commercialisation, and the Philippines, where field trials are going on. “There are many concerns with GE brinjal, which has been engineered to be resistant to certain insect pests using Bt genes from the soil bacterium Bacillus thuringiensis. These concerns include food safety and possible effects on organisms other than the pest insect (non-target organisms), such as beneficial insects and butterflies.”
One of the least known aspects of the GE Bt brinjal is its ability to cross with wild relatives or cultivated varieties. This is because there are no recent reviews in the scientific literature concerning species related to brinjal, and where they grow across Asia. This information is vital when addressing concerns regarding cultivation of GE Bt brinjal, because insect-resistance gives a selective advantage to the plant, increasing its ability to survive and reproduce. If the GE Bt brinjal cross-pollinates wild, weedy or cultivated relatives, the result is a hybrid offspring, which may grow more aggressively and thus become a problem weed, the report says.