SCIENCE & TECHNOLOGY

Global warming
Corals could be wiped out
Almost all the coral reefs in the world will disappear by the end of the century if global temperatures continue to rise as predicted by the Intergovernmental Panel on Climate Change (IPCC), a study has found.

Monkeys good at mental math
Monkeys performed about as well as college students at mental addition, US researchers said on Monday in a finding that suggests nonverbal math skills are not unique to humans.

World’s first ship tunnel
Norway has drawn up plans to build the world’s first shipping tunnel which would save time and money for vessels passing through a coastal area known for its dangerous seas.

Trends
“Bully” black hole
A “death star” galaxy is sending out a powerful jet of particles and magnetic radiation that is likely obliterating any possible life in its broad path, notably in a nearby galaxy, astronomers said on Monday.

  • Giant rats in Indonesia
  • Clone cats that glow
  • Fearless mice of Japan
Prof Yash Pal

Prof Yash Pal

THIS UNIVERSE
PROF YASH PAL
When we throw a stone while travelling in car, it gets more force than the ordinary throw. Why?
The answer to this question should be obvious. If car were travelling at 120 kilometers per hour then a stone dropped out by a child would be traveling at the same speed; this is similar to that of a ball thrown by some of the best fast bowlers in cricket.
 


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Global warming
Corals could be wiped out
Steve Connor


Increased levels of ocean acidity make it harder for coral reefs to form their calcium skeleton.
Increased levels of ocean acidity make it harder for coral reefs to form their calcium skeleton.

Almost all the coral reefs in the world will disappear by the end of the century if global temperatures continue to rise as predicted by the Intergovernmental Panel on Climate Change (IPCC), a study has found.

Rising temperatures and an increase in the acidity of the oceans will make it impossible for tiny coral organisms to make their calcium-based shells, according to the most definitive review yet of how well coral reefs will cope with global warming.

Scientist predict that unless countries drastically curb their emissions of carbon dioxide, some of the biggest reefs with the highest biodiversity, such as the Great Barrier Reef of Australia and the spectacular corals of the Caribbean, will become underwater deserts within the lifetime of people alive today.

A group of 17 eminent scientists from seven countries came to the pessimistic assessment after studying the worldwide scientific literature on rising concentrations of carbon dioxide, ocean acidity and global temperatures.

The study concluded that the expected increase in carbon dioxide this century will make earth uninhabitable for the vast majority of coral reefs. As a result, it will put intolerable pressure on the hundreds of millions of people who rely on the reefs for their livelihoods.

“This crisis is on our doorstep, not decades away,” said Prof Peter Mumby, of Exeter University. “Unless we act now, coral reefs are likely to dwindle into insignificance. They’ll be reduced to seaweed beds, rubble and a few scattered corals.

“The livelihoods of many millions of people living along the coasts of tropical developing countries will be among the first major casualties of rising levels of carbon in the atmosphere,” said Professor Mumby, one of the authors of the report published in the journal Science.

Corals suffer from increasing levels of carbon dioxide on two fronts. Rising temperatures cause “bleaching”, when the symbiotic algae that lives within the coral is expelled. Secondly, CO2 dissolving in the oceans boosts acidity which prevents the process of shell formation.

Current levels of carbon dioxide in the atmosphere are running at about 383 parts per million, but the IPCC predicts that that is likely to increase to at least 500ppm, with a corresponding 2C increase in global average temperatures by 2100.

About a third of the extra carbon dioxide added to the atmosphere by human activities is dissolved in the oceans which increases the concentration of carbonic acid.

This extra acidity dissolves certain carbonate minerals in seawater, notably a mineral called aragonite which is used by corals to make their external calcium skeleton.

“Before the industrial revolution, more than 98 per cent of warm water coral reefs were bathed with open ocean waters 3.5 times supersaturated with aragonite, meaning that corals could easily extract it to build reefs,” said Long Cao, a marine researcher at the Carnegie Institution in Stanford, California. “But if atmospheric carbon dioxide stabilises at 550ppm, and even that would take concerted international effort to achieve, no existing coral reef will remain in such an environment.”

Professor Mumby said levels of carbon dioxide were higher now than they have been for at least 740,000 years, and possibly higher than at any time in the past 20 million years.

“Coral reefs are the largest living structures on earth and are home to the highest biodiversity on the planet,” said Professor Mumby. “The environment that has enabled coral reefs to thrive for hundreds of thousands of years is changing so fast that compensatory biological responses are lagging behind.

“Better conservation, such as enforcement of fisheries regulations, is essential in order to buy time for coral reefs. If we can reduce local stresses and simultaneously curb carbon dioxide emissions to within 450ppm, then coral reefs and the food and housing security of millions of people could yet be saved.”

Professor Ken Caldeira, of the Carnegie Institution, another of the authors of the study, said: “These changes come at a time when reefs are already stressed by climate change, overfishing and other types of pollution. So unless we take action soon there is a very real possibility that coral reefs, and everything that depends on them, will not survive this century.” — The Independent
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Monkeys good at mental math

Monkeys performed about as well as college students at mental addition, US researchers said on Monday in a finding that suggests nonverbal math skills are not unique to humans.

The research from Duke University follows the finding by Japanese researchers earlier this month that young chimpanzees performed better than human adults at a memory game.

Prior studies have found non-human primates can match numbers of objects, compare numbers and choose the larger number of two sets of objects.

“This is the first study that looked at whether or not they could make explicit decisions that were based on mathematical types of calculations,” said Jessica Cantlon, a cognitive neuroscience researcher at Duke, whose work appeared in the Public Library of Science journal PLoS Biology (www.plosbiology.org).

“It shows when you take language away from a human, they end up looking just like monkeys in terms of their performance,” Cantlon said in a telephone interview.

Her study pitted the monkey math team of Boxer and Feinstein — two female macaque monkeys named for US senators Barbara Boxer and Dianne Feinstein of California — with 14 Duke University students.

“We had them do math on the fly,” Cantlon said.

The task was to mentally add two sets of dots that were briefly flashed on a computer screen. The teams were asked to pick the correct answer from two choices on a different screen. — Reuters
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World’s first ship tunnel

Norway has drawn up plans to build the world’s first shipping tunnel which would save time and money for vessels passing through a coastal area known for its dangerous seas.

Strong winds, high waves and powerful currents in the area of Stad on the southwest coast of Norway cause long delays while ships wait for calmer conditions.

A recent report from the Norwegian Coastal Administration recommended building the 1,700-metre (5,577 feet) tunnel and concluded that it would be cost effective.

The tunnel, estimated to cost around $310 million and take five years to build, would cut through a peninsula, saving ships the risky journey around the coastline.

The idea to build a shipping passage was first put forward long ago. Some say the first sketch was made in 1870, others say plans started around 1920 with the idea of building a canal through the peninsula.

But in the 1980s, the concept gained momentum and the government got involvement.

“What’s new is that we have managed to calculate the costs of waiting,” coastal director Kirsti Slotsvik told Reuters. She said the tunnel could also prevent loss of life.

Reduced stress for sailors, heightened quality of shipped products from reduced transport time and growth of tourism also weigh in favour of the tunnel, officials said. The Coastal Administration has recommended a design that would provide flexibility for future growth in ship sizes. — Reuters
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Trends
“Bully” black hole

A “death star” galaxy is sending out a powerful jet of particles and magnetic radiation that is likely obliterating any possible life in its broad path, notably in a nearby galaxy, astronomers said on Monday.

They said the two galaxies appear to be merging and the disturbance in the magnetic field caused by this movement may have awakened a dormant, supermassive black hole in one of the galaxies.

They have images of the deadly blast, spurting out from a system known as 3C321.

Data from NASA’s Chandra X-ray Observatory show both galaxies have supermassive black holes at their centers, and 3C321, the larger galaxy, is emitting this stream of energy and particles. The unnamed smaller galaxy apparently has swung into the path of this jet.

The astronomers agree that both galaxies are likely to have planetary systems but nothing resembling life on any planet could survive the blast. While such jets have been seen before, this is the first time one has been observed battering another galaxy, the researchers report in The Astrophysical Journal. — Reuters

Giant rats in Indonesia

Researchers in a remote Indonesian jungle have discovered a giant rat that is about five times the size of a typical city rat and a tiny possum, scientists said Monday.

Unearthing new species of mammals in the 21st century is considered very rare. The discoveries by a team of American and Indonesian scientists are being studied further to confirm their status.

The animals were found in the Foja mountains rainforest in eastern Papua province in a June expedition, said US-based Conservation International, which organised the trip in the Southeast Asian nation along with the Indonesian Institute of Science.

“The giant rat is about five times the size of a typical city rat,” said Kristofer Helgen, a scientist with the Smithsonian Institution in Washington. “With no fear of humans, it apparently came into the camp several times during the trip.”

The possum was described as “one of the world’s smallest marsupials.”

A 2006 expedition to the same stretch of jungle — dubbed by Conservation International as a “Lost World” because until then humans had rarely visited it — unearthed scores of exotic new species of palms, butterflies and palms. — AP

Clone cats that glow

South Korean scientists have cloned cats that glow red when exposed to ultraviolet rays, an achievement that could help develop cures for human genetic diseases, the Science and Technology Ministry said.

Three Turkish Angora cats were born in January and February through cloning with a gene that produces a red fluorescent protein that makes them glow in dark. One died at birth, but the two others survived, the ministry said. — AP

Fearless mice of Japan

Cat and mouse may never be the same. Japanese scientists say they’ve used genetic engineering to create mice that show no fear of felines, a development that may shed new light on mammal behaviour and the nature of fear itself.

Scientists at Tokyo University say they were able to successfully switch off a mouse’s instinct to cower at the smell or presence of cats — showing that fear is genetically hardwired and not learned through experience, as commonly believed.

“Mice are naturally terrified of cats, and usually panic or flee at the smell of one. But mice with certain nasal cells removed through genetic engineering didn’t display any fear,” said research team leader Ko Kobayakawa. — AP
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THIS UNIVERSE
PROF YASH PAL

When we throw a stone while travelling in car, it gets more force than the ordinary throw. Why?

The answer to this question should be obvious. If car were travelling at 120 kilometers per hour then a stone dropped out by a child would be traveling at the same speed; this is similar to that of a ball thrown by some of the best fast bowlers in cricket.

So if the stone is thrown forward through the car window, the speed of the car gets added to the speed at which you throw.

You also know that fast bowlers in cricket take a long fast run before throwing the ball. They are adding their running speed to that at which they can throw just standing still on the ground.

If we drink coffee or tea after eating sweets, they seem to be much less sweet. What is the reason?

I will hazard an answer even though I am not so certain about its accuracy.

Taste buds are receptors that fit in the molecules that give us a sensation of sweetness. After eating things that are very sweet these receptors are saturated with molecules.

There are few seats that are vacant. Therefore the signal of sweetness from things that are less sweet remains weak. Therefore things taste less sweet than they would if we had not taken the sweets beforehand.

In electrical wiring, what is the difference between the neutral and the ground?

The ground is connected to the ground and the neutral is not. The ground wire ensures that in case of a leakage a connected appliance does not acquire a voltage that might cause injury or malfunction.

The live terminal is the one to which the voltage is connected. It appears that there should be no separate identification of the live and neutral terminals when you are dealing with ac current. However for reasons of safety and connecting electrical networks it becomes prudent to do so.


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