Washington, Sept 28 (AN): Racing sled dogs are considered to be the ultra-athlete canine for their ability of covering 1,100 miles from Anchorage to Nome, Alaska, sometimes in just nine days, during the Iditarod Trail Sled Dog Race. Now, a new research sheds light on how they do it.

The study led by Dr. Michael Davis at the Oklahoma State University's Centre for Veterinary Health Sciences has focused how these dogs are capable of running continuously, despite heavy blizzards, temperatures as low as -40 Celsius F, and winds up to 60 mph.

The most striking feature of these canines is their ability to rapidly adapt to sustained strenuous exercise in 24-48 hours.

Conditioned dogs display most of the metabolic changes that are found in human endurance athletes during their first day of exercise, including depletion of muscle energy reserves, increases in stress hormones, evidence of cellular injury (such as to proteins, lipids and DNA), and oxidative stress.

However, with subsequent consecutive days of exercise at the same intensity, these changes are reversed. Within four days after exercise begins, the metabolic profile of the dogs returns to where it was before the race began, despite their sustained, strenuous exercise. When human ultra-athletes become fatigued, they stay that way until a period of recovery that may take a full day.

These dogs also have enormous aerobic capacity.

While the untrained sled dogs have an average aerobic capacity of 175 ml/kg/min VO2 max (ratio of volume of oxygen to body weight per minute), the aerobic capacity of the fully conditioned sled dogs is estimated to be about twice that (300 ml/kg/min).

The running dog's high-fat diet is converted to energy in the liver, and used as fuel in the initial stages of exercise. Preliminary data suggests that this process is a desirable trait intended to efficiently support exercise in the racers.

The mechanisms that make these four-legged athletes premiere in performance is still unknown.

Davis theorizes that it may involve the regulation of extremely thin membranes in the muscle fibres and changes in the cells that are responsible for the body's energy production.

"These are one-of-a-kind athletes. What we learn from them will undoubtedly tell us a lot about human performance as well," he said.

The findings will be presented at part of the American Physiological Society's (APS) conference. (ANI)

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Washington, September 28 (ANI): Researchers from Maastricht University in Amsterdam have found a possible solution in dealing with the increasing tourism in Antarctica that can form a threat for the vulnerable South Pole area, in the form of marketing the visitor rights to the highest bidder.

Tourism in Antarctica has grown dramatically. In 1985, just a few thousand people visited the area but in the season 2007/2008 more than 40,000 did the same.

A number of parties are concerned about the effects of this rapid growth with respect to safety, the environment, the scale of tourism and the lack of financial resources for monitoring and enforcement purposes.

They also have doubts about how this growth can be reconciled with the basic principles of the Antarctic Treaty System ATS. ntarctica is not a sovereign state and so legislation is difficult. With strict guidelines and codes of conduct, the umbrella organisation of Antarctic tour operators, IAATO, has been able to dispel many of the concerns.

However, this self-regulation is no absolute guarantee for a healthy tourism industry on Antarctica.

One possible solution is that of marketable visitor rights, as is already used in the climate policy by means of trading in CO2 emission rights.

First of all, a maximum annual number of tourist days in Antarctica will be set. To ensure a smooth transition, this maximum will be set higher than the actual number of tourists days used.

As soon as the demand for holiday days in Antarctica is higher than the maximum, the rights to the days will have a certain value.

By awarding the rights to the ATS, the income can be used, for example, for monitoring and enforcement purposes, issues for which there is little money at present.

The visitor rights will be auctioned: sold to the highest bidder. Then the buyers are free to trade the rights further.

This will ensure that the available 'space' in tourist days will be used for the most profitable forms of tourism.

This system of marketable visitor rights could allow three objectives to be realised: the scale of tourism and with this its effects will be limited, an urgently desired new source of funding will become available for monitoring and enforcement, and the tourism trade in the Antarctic area will remain financially healthy. (ANI)

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Washington, September 28 (ANI): Thanks to an automated system developed by a team of Princeton University computer scientists, archaeologists in Greece will now be able to virtually reconstruct wall paintings that hold valuable clues to the ancient culture of Thera, an island civilization that was buried under volcanic ash more than 3,500 years ago.

According to David Dobkin, the Phillip Y. Goldman '86 Professor in Computer Science and dean of the faculty at Princeton, the new technology has the potential to change the way people do archaeology.

"This approach really brings in the computer as a research partner to archaeologists," said Dobkin, who got the inspiration for the project after a 2006 visit to the archaeological site of Akrotiri on the island of Thera, which in present-day Greece is known as Santorini.

To design their system, the Princeton team collaborated closely with the archaeologists and conservators working at Akrotiri, which flourished in the Late Bronze Age, around 1630 B.C.E.

Reconstructing an excavated fresco, mosaic or similar archaeological object is like solving a giant jigsaw puzzle, only far more difficult.

The original object often has broken into thousands of tiny pieces - many of which lack any distinctive color, pattern or texture and possess edges that have eroded over the centuries.

As a result, the task of reassembling artifacts often requires a lot of human effort, as archaeologists sift through fragments and use trial and error to hunt for matches.

While other researchers have endeavored to create computer systems to automate parts of this undertaking, their attempts relied on expensive, unwieldy equipment that had to be operated by trained computer experts.

The Princeton system, by contrast, uses inexpensive, off-the-shelf hardware and is designed to be operated by archaeologists and conservators rather than computer scientists.

The system employs a combination of powerful computer algorithms and a processing system that mirrors the procedures traditionally followed by archaeologists.

"We mimic the archaeologists' methods as much as possible, so that they can really use our system as a tool," said Szymon Rusinkiewicz, an associate professor of computer science whose research team led the Princeton effort.

"When fully developed, this system could reduce the time needed to reconstruct a wall from years to months. It could free up archaeologists for other valuable tasks such as restoration and ethnographic study," he added. (ANI)

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Washington, September 28 (ANI): Mechanical engineers at the University of Strathclyde's Energy Systems Research Unit (ESRU) in Scotland is developing a dual-rotor turbine connected to the seabed by a cable that rides the tide like a kite on a windy day.

According to a report in Scientific American, the ESRU team's goal is to create a device that literally goes with the flow rather than resting on the sea bottom like an underwater windmill - a model already being developed by a handful of companies.

The kite and cable model is designed to facilitate placing tidal turbines in deep water, where the stronger current has the potential for providing reater power but also makes it extremely difficult to plant a turbine in the seabed.

"The problem with regular turbines is the bigger they get, the harder they work, and the more likely the force of the water is to damage the turbine," said Andrew Grant, an ESRU mechanical engineer. "Our turbine can fly like a kite in the water," he added.

Instead of planting the base of a turbine in the seabed, researchers need only plant an anchor for the tether.

Another key difference in ESRU's design is that the turbine has two rotors attached-one in front of the other that turn in opposite directions on a single axis.

The rotors' blades are made of either solid aluminum alloy or glass-reinforced plastic, depending on their sizes.

By having the rotors turn in opposite directions, Grant and his team are trying to cut down on reactive torque (which pushes the turbine in the opposite direction) so that the unit can be attached to a relatively simple mooring system even in very deep water.

But, Grant acknowledges that tidal-derived power has a long way to go before it can be used as a mainstream source of energy.

He expects it will be a decade or more before ESRU's turbines are ready to be used in earnest in the sea - much more testing must be done, in addition to the environmental impact studies and garnering of support from utility companies. (ANI)

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