Interesting 2....

From LiveScience.com

Ants Prefer Salt over Sugar

Ants have less of a sweet tooth and more of a preference for salty snacks, at least when they live in salt-poor areas far from the ocean, a new study finds.

All animals — from ants to humans — need salt to maintain their body's nerve and muscle activity and water balance.

Ants, though, typically swarm over sources of sugar because they need it for energy.

But researchers suspected those taste differences might vary with location and tested the salt-versus-sweet preferences of ants at various distances from the ocean, a source of salt.

The study, detailed in the Oct. 27 issue of the journal Proceedings of the National Academy of Sciences, was sponsored in part by the National Geographic Society and the Amazon Conservation Association.

The "cafeteria experiment" offered the ants a choice of cotton balls soaked in salt or sugar solution. Ants that lived more than 60 miles (100 kilometers) inland preferred the salt solution (which was less concentrated than the sugar solution).

This preference was mainly true of plant-eating ants, since carnivorous ants get enough salt from their prey. (Similarly herbivorous animals such as cows and deer get their salt from salt licks, while wolves and other predators get it from the bloody meat they eat.)

The researchers want to see if this pattern holds for all insects and even microbes. In particular, study lead author Michael Kaspari plans to see if spraying salt on forest leaf litter cranks up ecosystem activity, just as Gatorade improves the performance of sports teams.

Interesting...

From LiveScience.com

Why we love being scared

When you get scared, your heart rates soars, you breathe faster, your muscles tighten, and your attention focuses — all part of the fight or flight response. But when you know there is no real threat, the adrenaline rush can be enjoyable, scientists say.

One explanation for why we love scary movies is that we're not so much afraid as we are excited. Another is that we are willing to endure the terror in order to enjoy a euphoric sense of relief at the end.

A newer idea, put forth last year in the Journal of Consumer Research, suggests horror movie viewers are happy to be unhappy. People experience both negative and positive emotions simultaneously, the thinking goes. "The most pleasant moments of a particular event may also be the most fearful," wrote Eduardo Andrade of the University of California, Berkeley and Joel B. Cohen at the University of Florida.

The best

Alfred Hitchcock was, of course, the master at teasing all these senses. Konzett: "Even though we actually see only a small amount of blood (chocolate syrup going down the drain) and very little gore, if any, in this short two-minute scene, it has profoundly scared several generations of people, especially women, with many saying they are afraid to take showers for days. Very few horror scenes have had this kind of impact."

Even the low-budget "Texas Chainsaw Massacre," often criticized for gore and violence, "actually has much less blood than people imagine, with many of the killings occurring off camera," notes film reviewer and LiveScience columnist Benjamin Radford.

Steven Spielberg's 1975 "Jaws" left an entire generation afraid to enter the water for fear of shark attacks, Konzett notes. Yet Spielberg sidestepped outright gore for the most part, using thumping music, murky water and the constant threat of attack to terrify viewers.

"Films such as 'Psycho' and 'Jaws' capture the helplessness of people, catching them when they are most vulnerable. This is why many decades later, they are still popular among the younger generation in spite of contemporary horror films that are more sensational and filled with blood and gore," she says.

Animals Stressed Out, Too

Came across this interesting article -

The economy, the election, and myriad other problems are really stressing out ... pets.

When humans get stressed, often their pets take on that stress, too.

"Dogs and cats are very good at picking up stress in people, as are birds," said James Morrisey, a veterinarian at the College of Veterinary Medicine of Cornell University in New York. "I've worked with a parrot who lived with a woman who had a seizure disorder, and the parrot could tell when she was about to have a seizure and warn her."

In addition to carrying the burdens of people, animals — especially wild creatures — have plenty of their own to stress about. Animals will even seek out "comfort food" when they're all wigged out. And stress in animals, as with humans, can be a good or a bad thing.

"In general, the more intelligent an animal is, the more psychological stress it can undergo," Morrisey said. "The less you're thinking about things, the less psychological stress you can potentially be under."

Complete article at - LiveScience.com

Tragic...

It so sad that we don't realize the consequences of our actions.


From LiveScience.com

Warming is also forcing some mountain plant species to adapt by moving to higher altitudes as it kills them in their traditional ranges. In Southern California, for example, warming temperatures and longer dry spells have killed thousands of tree and plants, while pushing their habitats an average of 213 feet up the Santa Rosa Mountains over the past 30 years, according to a new study detailed in the Aug. 11 issue of the journal Proceedings of the National Academy of Sciences.

Previous studies have also catalogued the ways that climate change is knocking the nature out of whack: birds are migrating earlier in the season; reptiles and amphibians are also heading for the hills to reach cooler climes; and the timing of plant blooms is shifting as the Earth heats up.

Whole article at - Plants and Animals Move as Climate Warms

Kite Power?

I love the idea of renewable energy. Not only because it is clean and (can be) abundant but there is huge potential for it to be cheap too. Interesting article I came across on Live Science. It talks about using kites instead of traditional wind turbines to generate electricity.

Read on if you are interested. Making a few sections bold for those who are partly interested.

Source - LiveScience.com

Tie one end of a string to a piece of fabric and you have a kite; but tie the other end to a generator and you have a source of electricity.

Although it can only turn a generator during part of its flight, a kite can reach the strong winds at high altitude with less fuss than a traditional wind turbine.

"The main reason to go to kites is that wind turbines require a lot of material," said Moritz Diehl from the Catholic University (K.U.) of Leuven, Belgium. "By saving on parts, kites can be more economical."

Diehl thinks the cost of electricity from kites could be a quarter of what it is from wind turbines.

Trading torque for tension

One factor in making use of the wind is knowing that its force becomes stronger the faster an object moves relative to it.

For this reason, the tips of a wind turbine — which typically move 8 to 10 times faster than the wind speed — experience the most force. This strong tip-force creates a torque that turns the turbine's electric generator.

"The rest of the construction [the inner part of the rotor and the tower] is just there to support the tips," Diehl told LiveScience.

A kite can capture the same wind force without needing the costly support structure. This is because it transmits the force not through a torque but through the tension in the kite line.

However, like a turbine's tip, more force can be had if the kite is moving quickly relative to the wind. Diehl and his colleagues have modeled power-generating kites and shown that it is possible to steer them in a kind of figure-8 pattern that increases the force by a factor of 100 more than remaining still.

Pumping

The researchers have also shown that the optimum way to unfurl the kite line is at one-third the speed of the wind. This allows electricity to be generated from the turning spool, while keeping the kite at a fairly constant altitude of around 1300 feet (400 meters).

Of course, this can only work for a short time before the line runs out and the kite needs to be reeled back in. Diehl realized a few years ago that the amount of energy expended during reeling-in could be reduced by angling the kite's nose down.

By continuously "pumping" the kite out and in, out and in, Diehl's group has shown that 5 megawatts of power — typical of modern wind turbines — can be generated from a 500-square-meter kite (5400-square-foot) with a line 1.3 kilometers (0.8 miles) long.

In each pumping cycle, there would be 16 seconds of power generation while unfurling and 4 seconds of down-time while reeling-in.

Besides having lower material costs than traditional wind turbines, Diehl said that kites can reach higher altitudes where the wind is stronger and more constant.

Changing tacks

There are other ideas on how to generate energy from kites.

One group at Delft University of Technology in the Netherlands has proposed stringing a large number of kites along a circular line that would extend 6 miles (10 kilometers) into the sky. The whole system would turn like a waterwheel, as the kites would change tilt to go up or come down. Called the Laddermill, it could generate 100 megawatts of electricity, the researchers estimate.

An Italian company called Kite Gen has a similar idea, but with the "wheel" laid flat on the ground. The design calls for several kites attached to a kilometer-wide spinning carousel. The tilt of each kite could be controlled so that it only pulls on the carousel at specific points in the rotation.

For now, though, both the Delft group and the Kite Gen engineers have prototypes based on Diehl's pumping that can generate a few kilowatts of electricity.

Diehl also suspects Makani Power, which received $10 million last year from Google, is developing a similar sort of kite technology in relative secrecy.

It is also worth noting that kites are being used to tow cargo ships. In two demonstrations this year, Germany-based SkySails has shown that its kites can reduce fuel usage by 20 percent.

Blowing in the wind

Despite being "a fascinating and exciting idea," many technological hurdles remain for power-generating kites, said Manfred Morari, head of the Automatic Control Laboratory at ETH Zurich in Switzerland.

For one, the kites are inherently unstable. Researchers are developing automatic controls that can use data from sensors on the kite to correct for wind changes that blow the kite off course.

Another problem is scaling up systems so that they can be commercially viable.

"The kites must become bigger and bigger," said Bernhard Hoffschmidt of the Solar-Institute Jülich at Aachen University in Germany. "This will probably create problems on materials and life time."

Still, Hoffschmidt thinks that simple kite systems could be ideal for difficult locations, such as offshore.

"One of the major problems for offshore wind parks today is the needed time of excellent weather to install the units," Hoffschmidt said. Kites, on the other hand, could be installed on anchored buoys, "which can easily be installed and de-installed with a lower environment impact."