Why We Walk … and Run … And Walk Again to Get Where We're Going

You have to get to a bus stop to catch the once-an-hour express ... or to a restaurant to meet a friend ... or to a doctor's office. You've got maybe a half a mile to cover and you're worried you'll be late. You run, then you stop and walk, then run some more.

But wait. Wouldn't it be better to run the whole way?

Not necessarily.

A new study by an assistant professor of mechanical engineering at Ohio State University tests the theory that people subconsciously mix walking and running so they get where they need to. The idea is that "people move in a manner that minimizes energy consumption," said the professor, Manoj Srinivasan.

Srinivasan asked 36 subjects to cover 400 feet (122 meters), a bit more than the length of a football field. He gave them a time to arrive at the finish line and a stopwatch. If the deadline was supertight, they ran. If they had two minutes, they walked. And if the deadline was neither too short nor too far off, they toggled between walking and running.

The takeaway: Humans successfully make the walk-run adjustment as they go along, based on their sense of how far they have to go. "It's not like they decide beforehand," Srinivasan said. (Get tips, gear recommendations, and more in our Running Guide.)

The Best Technique for "the Twilight Zone"

"The mixture of walking and running is good when you have an intermediate amount of time," he explained. "I like to call it 'the Twilight Zone,' where you have neither infinite time nor do you have to be there now."

That ability to shift modes served ancient humans well. "It's basically an evolutionary argument," Srinivasan said. A prehistoric human seeking food would want to move in a way that conserves some energy so that if food is hard to find, the hunter won't run out of gas—and will still be able to rev it up to escape predators.

The study, published on January 30 in the Journal of the Royal Society Interface, doesn't answer that question of how we make such adjustments.

Runners: Take a Break if You Need It

The mix of walking and running is also something that nonelite marathoners are familiar with. Covering 26.2 miles might take less of a toll if the runner stops running from time to time, walks a bit, then resumes a jogging pace. "You use less energy overall and also give yourself a bit of a break," Srinivasan noted. (Watch: An elite marathoner on her passion for running.)

One take-home lesson is: Runners, don't push it all the time. A walk-run mix will minimize the energy you expend.

Lesson two: If you're a parent walking with your kid, and the kid lags behind, then runs to catch up, then lags again, the child isn't necessarily trying to annoy you. Rather, the child is perhaps exhibiting an innate ability to do the walk-run transition.

Potential lesson three: The knowledge that humans naturally move in a manner that minimizes energy consumption might be helpful in designing artificial limbs that feel more natural and will help the user reduce energy consumption.

The big question for Manoj Srinivasan: Now that he has his walk-run theory, does he consciously switch between running and walking when he's trying to get somewhere? "I must admit, no," he said. "When I want to get somewhere, I just let the body do its thing." But if he's in a rush, he'll make a mad dash.

"Talk to you tomorrow," he signed off in an email to National Geographic News. "Running to get to teaching now!"

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Water wars loom as the US runs dry

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Tennis: Nadal out of Brazil Open doubles over knee fear

SAO PAULO: Rafael Nadal will not play his scheduled doubles match at the Brazil Open Wednesday because of "knee overuse", organisers said.

But they added that the Spanish star intends to play his opening singles match Thursday against Brazilian Joao Souza.

World number five Nadal had been scheduled to team up with Argentina's David Nalbandian in a second-round encounter against Argentine Horacio Zeballos and Austrian Oliver Marach on Wednesday.

Former world number one Nadal only returned to the tour in Chile last week, where he lost in the final, after a seven-month injury absence.

"The conditions are very difficult. The court is not in the best condition and the ball is very difficult to control," Nalbandian told a press conference.

Nalbandian and Nadal won a hard-fought match 6-3, 3-6, 11-9 against Spaniards Pablo Andujar and Guillermo Garcia-Lopez on the court late Tuesday.

"It's too bad I cannot play the doubles after the match Rafa and I had (yesterday)," the Argentine said. "But he (Nadal) has to take care of himself and prepare for a long and hard year".

At a press conference Tuesday, Nadal complained about having to play so many hardcourt events

"That is a theme among the players and doctors," he said.

While conceding that reducing the number of events on hard surface was not possible at this time, he added: "I think that the ATP has to work to think of how to lengthen tennis players' careers."

"Can you imagine football players playing on cement?" he added.

"I am a bit tired after a hard week in Chile. But it was positive. The process of recovery follows its course," Nadal also said. "As always I come here to do the best possible and hope that things turn out all right."

Asked when he expected to be 100 per cent fit, he responded: "I cannot know the future. If my knee allows, I will do everything possible to be at my best."

"I am a player who plays with a lot passion, a lot of energy. I suppose that does not help the knee."

"My long-term objective is to be in Brazil in 2016 (for the Rio Summer Olympics). I am going to work to arrive in good condition at what are likely to be my last Olympics," he said.

Considered by many to be the best ever claycourt player, seven-time French Open champion Nadal was back in Chile last week for the first time since a surprise second-round exit at Wimbledon in June.

The world number five lost the singles and doubles finals in the Vina del Mar Open on Sunday.

- AFP/jc

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Commodore 65 prototype sells for $7,625

Did you adore your 64? Well, wanna buy a 65? That'll cost you.

Earlier this month we saw how fans of vintage home computers can get a little crazy on eBay, bidding up the price of a 1983 10MHz Texas Instruments TI-99/8 to $3,240.

Well that's nothing compared with the enthusiasm that Commodore commands. A prototype Commodore 65 more than doubled the winning TI bid when it sold on eBay recently for a whopping $7,625.

Described as by the seller as "the proposed successor to the most popular computer of all time," the C65 is a prototype engineering unit that's missing some chips. It doesn't even work, but it came with a prototype Mitsumi keyboard.

Regardless, bidders sure wanted to get their hands on it.

Developed around 1991, the 3.54MHz Commodore 65 was designed to build on the C64's success and, like the Commodore 128, be generally compatible with its software.

The 8-bit C65 had improved graphics, a built-in 3.5-inch floppy drive, up to 8MB of RAM, and 128K ROM. It ran Commodore BASIC 10.0.

Unfortunately the C65 project was cancelled before it got to market, and Commodore declared bankruptcy in 1994.

However, some C65s were made as engineering prototypes and survived the company's liquidation. The number of extant units is unknown; estimates range from dozens to hundreds.

The machine's MRSP was only $300-$350, according to this C65 page.

"A working 65 is the Holy Grail of the Commodore 8-bit world these days," the site says.

Until the Grail turns up, I'll just keep watching C64 ads.

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Are Honeybees Losing Their Way?

A single honeybee visits hundreds, sometimes thousands, of flowers a day in search of nectar and pollen. Then it must find its way back to the hive, navigating distances up to five miles (eight kilometers), and perform a "waggle dance" to tell the other bees where the flowers are.

A new study shows that long-term exposure to a combination of certain pesticides might impair the bee's ability to carry out its pollen mission.

"Any impairment in their ability to do this could have a strong effect on their survival," said Geraldine Wright, a neuroscientist at Newcastle University in England and co-author of a new study posted online February 7, 2013, in the Journal of Experimental Biology.

Wright's study adds to the growing body of research that shows that the honeybee's ability to thrive is being threatened. Scientists are still researching how pesticides may be contributing to colony collapse disorder (CCD), a rapid die-off seen in millions of honeybees throughout the world since 2006.

"Pesticides are very likely to be involved in CCD and also in the loss of other types of pollinators," Wright said. (See the diversity of pollinating creatures in a photo gallery from National Geographic magazine.)

Bees depend on what's called "scent memory" to find flowers teeming with nectar and pollen. Their ability to rapidly learn, remember, and communicate with each other has made them highly efficient foragers, using the waggle dance to educate others about the site of the food source.

Watch as National Geographic explains the waggle dance.

Their pollination of plants is responsible for the existence of nearly a third of the food we eat and has a similar impact on wildlife food supplies.

Previous studies have shown certain types of pesticides affect a bee's learning and memory. Wright's team wanted to investigate if the combination of different pesticides had an even greater effect on the learning and memory of honeybees.

"Honeybees learn to associate floral colors and scents with the quality of food rewards," Wright explained. "The pesticides affect the neurons involved in these behaviors. These [affected] bees are likely to have difficulty communicating with other members of the colony."

The experiment used a classic procedure with a daunting name: olfactory conditioning of the proboscis extension reflex. In layman's terms, the bee sticks out its tongue in response to odor and food rewards.

For the experiment, bees were collected from the colony entrance, placed in glass vials, and then transferred into plastic sandwich boxes. For three days the bees were fed a sucrose solution laced with sublethal doses of pesticides. The team measured short-term and long-term memory at 10-minute and 24-hour intervals respectively. (Watch of a video of a similar type of bee experiment.)

This study is the first to show that when pesticides are combined, the impact on bees is far worse than exposure to just one pesticide. "This is particularly important because one of the pesticides we used, coumaphos, is a 'medicine' used to treat Varroa mites [pests that have been implicated in CCD] in honeybee colonies throughout the world," Wright said.

The pesticide, in addition to killing the mites, might also be making honeybees more vulnerable to poisoning and effects from other pesticides.

Stephen Buchmann of the Pollinator Partnership, who was not part of Wright's study, underscored how critical pollinators are for the world. "The main threat to pollinators is habitat destruction and alteration. We're rapidly losing pollinator habitats, natural areas, and food—producing agricultural lands that are essential for our survival and well being. Along with habitat destruction, insecticides weaken pollinators and other beneficial insects."

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Plants listen more closely to kin than strangers

It is not just humans that like a natter with their nearest and dearest – plants pay most attention to their closest relatives.

When an insect bites a leaf, many plants release volatile chemicals to prime their neighbours for attack. The defences this triggers vary – some plants respond by attracting predatory insects that eat the herbivores, others make themselves less tasty.

Now Richard Karban of the University of California, Davis, has shown that for the sagebrush, responses to these warning signals can vary with relatedness.

At the start of three growing seasons, Karban's team exposed different branches of the same plants to volatile chemicals. The substances came from relatives of the same species whose leaves had been clipped to trigger chemical release.

By the end of the seasons, herbivores had done less damage to the branches exposed to chemicals from close relatives than to those receiving signals from more distant relatives – the warning probably prompting the plants to release herbivore-deterring chemicals, says Karban.

He has previously shown that the blend of volatiles varies enormously between individuals – "so much so that big peaks in some individuals are undetectable in others", he says.

However, there is some similarity between family members. Karban thinks this variability is being exploited by the plants as a kind of family-specific signature, to prevent eavesdroppers from listening in and to give those that share the same genes a greater chance of survival.

Some plants are genetically more resistant to being eaten than others, so it makes sense that plants should care more about their kin's fate than that of the general population.

"It is very elegant work," says Susan Dudley from McMaster University in Ontario, Canada, who has shown that plants competing for space in a small pot are less aggressive if they are related to their neighbours.

She thinks this kind of kin-recognition is probably common among many plants.

Journal Reference: Proceedings of the Royal Society B, doi: 10.1098/rspb.2012.3062

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17 gunmen dead in Thai military base attack

 

BANGKOK, Thailand: Scores of heavily-armed gunmen stormed a military base in unrest-plagued southern Thailand, an army spokesman said on Wednesday, in a major assault that left at least 17 militants dead.

"Some 100 fully armed militants stormed the base, where there were 60 marines," Colonel Pramote Promin, southern army spokesman, told AFP.

He said the attack, one of the most ambitious in several years of violence in Thailand's three southernmost provinces, had left at least 17 assailants dead. No military casualties were reported.

- AFP/de

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BlueStacks brings a boat-load of Android apps to the Surface Pro

Thanks to BlueStacks, Angry Birds can officially be found on almost every Surface.

(Credit:
BlueStacks)

Hunting around the Windows store for your favorite apps can sometimes be a sad and demoralizing experience, particularly if you just dropped about a grand for that slick new Surface Pro from Microsoft.

Enter the startup BlueStacks on its multicolored digital steed prepared to liberate the Surface with its
Android app player, shouting "Freedom!" at the top of its lungs a la Mel Gibson in "Braveheart."

Actually, you can just download a version of the BlueStacks App Player optimized for the
Surface Pro that was just released today, but I do recommend at least donning a bit of blue war paint before clicking to make for a more memorable experience.

BlueStacks' app player is a sort of emulator that allows the whole universe of more than 750,000 Android apps (malware and all) to run on a PC. The Windows and Mac versions were first released last year, and the new
Windows 8/Surface Pro download greatly expands the options for users who previously might have shed a tear when perusing the less than 40,000 apps currently offered on Microsoft's official Windows app market.

According to a release from the company, BlueStacks is officially supported Windows 8 software, which is perhaps the most interesting part of the tale, especially given jabs at Redmond like this one from BlueStacks CEO Rosen Sharma in the statement:

The number of mobile apps being written overall is expanding exponentially and Microsoft has not added apps to the handful it has. Our goal is to get people more value out of their Surface Pro and Win8 devices.

BlueStacks has struck a handful of deals with PC and component makers like AMD, Asus and Lenovo and says that BlueStacks will come pre-loaded on millions of PCs in the future.

Forget about zombies, folks, from here on out, it looks like we'll have to look for Angry Birds around every corner and on every, uh...Surface.

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Where Will Pope Benedict XVI Retire?

Someone with a suspicious mind and deep knowledge of Vatican trivia might have guessed that something was going on months ago. Last November, a community of cloistered nuns vacated the  Mater Ecclesiae monastery, located inside Vatican Gardens, two years before they were expected to do so.

The monastery has since been closed for renovation.

On Monday, in the press conference that followed Pope Benedict XVI's announcement that he will resign at the end of the month, Father Federico Lombardi, director of the Holy See Press Office,  revealed that the monastery will be the retired pontiff's new home. (Photo Gallery: Inside the Vatican.)

"When renovation work on the monastery of cloistered nuns inside the Vatican is complete, the Holy Father will move there for a period of prayer and reflection," Lombardi said.

Until then, the pope will stay at the Apostolical Palace and the Pontifical Villas in Castel Gandolfo, a small lake town about 15 miles (24 kilometers) southeast of Rome, which serves as the traditional summer residence for popes.

The Mater Ecclesiae monastery was founded in 1992 by Benedict's predecessor, John Paul II, "to create a place to house an international convent for contemplative life within the walls of Vatican City," according to the Vatican City State website.

It has housed small communities of cloistered nuns whose main task has been to provide spiritual assistance to the pope and to the Roman Catholic Church as a whole by praying in Latin and singing Gregorian chants.

The nuns would also embroider papal garments and cultivate a small organic orchard and a rose garden next to their residence. In a 2009 interview with the Vatican newspaper L'Osservatore Romano, the monastery's then abbess said that Benedict particularly appreciated the special-recipe marmalade that the nuns would prepare out of the oranges and lemons they picked in the Vatican orchard.

It is not yet clear for how long the soon-to-be-former pope will stay at the monastery. Lombardi has said that Benedict will not participate in the March conclave that will elect his successor, stressing that there will be "no confusion or division arising from his resignation."

Lombardi also said that he wasn't sure of Benedict's future title-there are no canon law provisions or historical precedents regarding the statute, prerogatives, or titles for a retired pope.

Resignations of Popes Past

Only a handful of popes have willfully or forcefully resigned in the church's history, the last case going back to 1415, almost 600 years ago.

"It was Pope Gregory XII, who, in a very sacrificial gesture, offered to resign so that the Council of Constance could assume his power and appoint a new pope, and in so doing bring an end [to the] Great Western Schism," Donald Prudlo, associate professor of history at Jacksonville State University in Alabama, told Vatican Radio.

Italian and foreign commentators have been likening Benedict's choice to a famous case of papal abdication-that of Celestine V, who was elected in 1294 and left the Roman throne only five months later.

"At the end of the 13th century, a very holy hermit named Peter was elected as Pope Celestine V in order to break a deadlock in the conclave that had lasted nearly three years," Prudlo explained. "He was elected because of his personal holiness, sort of a unity candidate. And once he got there, being a hermit, not used to the ways of the Roman Curia, he found himself somewhat unsuited to the task."

So he resigned and lived as a hermit—or, some historians say, as a prisoner—in a castle belonging to his successor, Boniface VIII, before dying in 1296.

Celestine is widely recognized as the object of Dante Alighieri's scolding verses in his Divine Comedy. The former pope was proclaimed saint in 1313.

In 2009, Benedict XVI visited Celestine's tomb in L'Aquila (map) and left the pallium—a vestment that is the symbol of papal authority—on the grave. Now that gesture is being interpreted as a premonition of the choice he would eventually make.

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Wanted Ex-Cop Possibly in Shootout, Chase

Fugitive former cop Christopher Dorner has barricaded himself inside a mountain cabin near Big Bear, Calif., and exchanged gunfire with police who had pursued him after he broke into a home in the area, authorities said.

Two San Bernadino County Sheriff's deputies injured in the firefight and subsequently airlifted to a nearby hospital. The extent of their injuries is unknown.

Dozens of local, state and federal authorities are at the scene in the San Bernadino Mountains, surrounding the cabin and engaged in an intense standoff with Dorner, a former Navy marksman who swore to kill police and their family members in a manifesto discovered online last week.

Dorner is believed to have broken into another home nearby and taken two women hostage before stealing a car, police said. Officials say Dorner crashed the vehicle and fled on foot, where sheriff's deputies and state Fish and Game officers exchanged fire with him, before he barricaded himself in the cabin.

The two hostages, who were tied up by Dorner but later escaped, were evaluated by paramedics and were determined to be uninjured.

Police have sealed all roads going into the area and imposed a no-fly zone above the cabin, which is in a wooded area that has received several inches of snow in recent days.

Four Big Bear area schools were briefly placed on lockdown.

The San Bernardino County Sheriff's Department stopped all traffic leaving the area and thoroughly searched vehicles, as SWAT team and tactical units could be seen driving toward the cabin, their sirens blaring.

Los Angeles Police Department/AP Photo

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Authorities believer Dorner may be watching reports of the standoff and have asked media not to broadcast images of police surrounding the cabin.

"If he's watching this, the message... is: Enough is enough. It's time to turn yourself in. It's time to stop the bloodshed. It's time to let this event and let this incident be over," said Los Angeles Police spokesman Andy Smith, told reporters at a press conference.

Dorner faces capital murder charges that involve the killing of Riverside police officer Michael Crain, who was gunned down in an ambush last Thursday.

Since then a massive manhunt has been underway, focused primarily in the San Bernardino Mountains, but extending to neighboring states and as far away as Mexico.

A capital murder charge could result in the death penalty if Dorner is captured alive and convicted. Crain was married with two children, aged 10 and 4.

The charges do not involve the slayings of Monica Quan and her fiance, who were found shot to death Feb. 3. Quan was the daughter of former LAPD Capt. Randal Quan, who was mentioned as a target of Dorner's fury in his so-called "manifesto," which he posted on his Facebook page.

PHOTOS: Former LAPD Officer Suspected in Shootings

In the 6,000 word "manifesto," Dorner outlined his anger at the Los Angeles Police Department for firing him, and made threats against individuals he believed were responsible for ending his career with the police force five years ago.

Dorner's grievance with police goes back five years when he was fired after filing a false report accusing other cops of brutality.

The LAPD has assigned 50 protection details to guard officers and their families who were deemed possible targets.

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