April 12, 2006

Why A Spider Hanging From A Thread Does Not Rotate

Posted in Animals Kingdom, News Headlines at 12:49 am by miharuyouth

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The extraordinary properties of spider's thread are like a blessing for researchers working on polymers. However, the amazing twisting properties it displays are still not very well understood. How can one explain the fact that a spider suspended by a thread remains completely motionless, instead of rotating like a climber does at the end of a rope? Researchers at the Laboratoire de physique des lasers (CNRS/University of Rennes) have described the exceptional properties of this material which still has some secrets to reveal. The results will be published in Nature on 30 March 2006.

Fasten an object to the end of a vertically suspended thread. Give it a slight twist and let go. You will observe that the object rotates for a certain length of time and with a certain amplitude, depending on the material of the thread. Now observe a spider suspended from its thread: It is stable, doesn't move, spins its thread in a perfectly straight line and always recovers its balance after environmental disturbances.

By experimenting with a torsion pendulum to which they attached a mass equivalent to a spider's weight, researchers at the Laboratoire de physique des lasers (CNRS/University of Rennes) compared the dynamic reactions of different types of thread to a 90° rotation. The results are revealing: a KevlarTM filament (which is synthetic) behaves like an elastic, with reduced oscillations. A copper thread oscillates slightly but does not return to its original shape, and becomes more fragile as a result of these oscillations. Spider's thread, on the other hand, is very efficient at absorbing oscillations, regardless of air resistance, and retains its twisting properties during the experiments. It also returns to its exact original shape. Certain alloys, such as Nitinol, possess similar properties but must be heated to 90° to return to their original shape.

The amazing properties of spider's thread have been known for several years: its ductility, strength and hardness surpass those of the most complex synthetics fibers . It now also seems that through natural selection, spider's thread has evolved into a material with “self-shape memory effect” which allows it to return to its original configuration without outside stimulus. This complex dynamic process has recently been represented as a “stacked” model which the authors use to depict the relaxation of the different proteins in spider's thread.

Editor's Note: The original news release can be found here.

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March 19, 2006

Singing frog’s ‘ultrasonic croak’

Posted in Animals Kingdom, News Headlines at 5:19 am by miharuyouth

Noisy surroundings led to the creative croak, scientists say (Image: Albert Feng)

A rare Chinese frog has entered the record books as the first amphibian known to communicate using ultrasound.

Until now, only a few mammals – such as bats, whales and dolphins – have been found to use the very high frequency sound to contact each other.

The frog may have evolved the mechanism to be heard above the babble of running water, scientists tell this week’s edition of the journal Nature.

Canada’s lonely killer whale dies

Posted in Animals Kingdom, News Headlines at 5:16 am by miharuyouth

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A lonely killer whale that captured the hearts of many Canadians is believed to have died after being hit by a tugboat propeller, officials have said.
The orca, nicknamed Luna, became separated from his family off Vancouver Island in British Columbia in 2001, and soon started playing with boats.

It later sparked a fierce row between scientists and aboriginal Indians.

The Indians thwarted efforts to reunite Luna with his pod, believing he was the reincarnation of a dead chief.

The seven-year-old male mammal appeared to have been sucked into a propeller after miscalculating its power, John For from Canada’s department of oceans and fisheries said.

“Luna has been fixated on boats for a number of years now,” Mr Ford told Vancouver’s Global television, adding that it was “a tragic accident”.

Luna is believed to have died instantly. The remains still need to be formally identified by experts.

‘Re-incarnated chief’

The 1.8-tonne creature proved an instant hit with tourists, and his exploits soon gained attention in the world media.

Despite this, scientists – who had seen him as a safety hazard – wanted to return Luna to its family, some 300km down the coast.

Aboriginal Indians, however, managed to derail the effort.

They had told the story of their chief who on his deathbed in 2001 promised to return as a whale.

Three days after the chief died, Luna first appeared in their harbour.

The Indians used their traditional canoes to lure Luna away from the scientists’ pen.

Divers discover new crustacean-Animal is covered with blond hairlike strands

Posted in Animals Kingdom, News Headlines at 5:11 am by miharuyouth

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PARIS – A team of American-led divers has discovered a new crustacean in the South Pacific that resembles a lobster and is covered with what looks like silky, blond fur, French researchers said Tuesday.

Scientists said the animal, which they named Kiwa hirsuta, was so distinct from other species that they created a new family and genus for it.

The divers found the animal in waters 7,540 feet (2,300 meters) deep at a site 900 miles (1,440 kilometers) south of Easter Island last year, according to Michel Segonzac of the French Institute for Sea Exploration.

The new crustacean is described in the journal of the National Museum of Natural History in Paris.

The animal is white and just shy of 6 inches (15 centimeters) long — about the size of a salad plate.

In what Segonzac described as a “surprising characteristic,” the animal’s pincers are covered with sinuous, hairlike strands.

It is also blind. The researchers found it had only “the vestige of a membrane” in place of eyes, Segonzac said.

The researchers said that while legions of new ocean species are discovered each year, it is quite rare to find one that merits a new family.

The family was named Kiwaida, from Kiwa, the goddess of crustaceans in Polynesian mythology.

The diving expedition was organized by Robert Vrijenhoek of the Monterey Bay Aquarium Research Institute in California.

Copyright 2006 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

 

Samsung SGH-i310 first Mobile phone with 8 GB hard drive

Posted in News Headlines, Technology at 4:59 am by miharuyouth

Samsung continues to awe us with it’s innovation in mobile phones, this time with a phone with 8GB hard drive. The SGH-i310 is an upgrade to the Samsung SGH-i300x which has a 4GB hard drive. The i310’s mammoth 8GB hard drive can hold upto 2000 songs. It’s MP3 player can playback MP3, WMA and AAC files and includes powerful stereo speakers. The i310 runs on Windows Mobile 5.0 and includes a 2 Megapixel Camera with video recording at 30 FPS. It includes USB 2.0 and can function as a USB mass storage device so you can say goodbye to your Flash drives. It features Bluetooth, Infrared, GPRS and high speed EDGE connectivity. The i310 includes dedicated Music player keys and a unique jog dial for browing through playlists.

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