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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Dorner Confirmed Dead in Autopsy on Cabin Remains

Christopher Dorner, the ex-Los Angeles police officer who declared himself on a killing spree against his former law enforcement colleagues, is dead.

Authorities this evening confirmed that remains found after a fiery standoff at a California mountain cabin Tuesday were, in fact, Dorner's.

"The charred human remains located in the burned out cabin in Seven Oaks have been positively identified to be that of Christopher Dorner," the San Bernardino County Sheriff-Coroner's Office said in a written statement. "During the autopsy, positive identification was made through dental examination."

FULL COVERAGE: Christopher Dorner Manhunt

PHOTOS: Former LAPD Officer Suspected in Shootings

In a 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 was fired after filing what the LAPD determined to be a false report accusing other cops of brutality.

Dorner is suspected of killing four people, including 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 the manifesto.

Christopher Dorner Hostages: 'He Just Wanted to Clear His Name' Watch Video

Christopher Dorner Believed Dead After Shootout With Police Watch Video

Christopher Dorner Believed Dead After Shootout with Police Watch Video

Dorner is also suspected in the shooting death of Riverside, Calif., Police Officer Michael Crain, whose funeral was Wednesday.

San Bernardino Sheriff's Deputy Jeremiah MacKay, 35, a 15-year veteran and the father of two children, was killed in Tuesday's shootout at the cabin.

A second San Bernardino County sheriff's officer had to undergo multiple surgeries after he was wounded in the cabin shootout, and other officers also were wounded in earlier alleged encounters with Dorner.

After Crain's death, police tracked Dorner to the Big Bear Lake area of Southern California, where his burning truck was found in the mountains late last week.

A couple with a cabin in the area were some of the last people to see Dorner before his final encounter with police. Their 911 call to police triggered a chase that concluded with the fiery standoff at the nearby cabin.

The couple, Karen and Jim Reynolds, said at a news conference Wednesday that their ordeal lasted a few minutes but seemed like hours.

The Reynolds believe Dorner, 33, was holed up starting Friday in their unoccupied cabin in Big Bear, Calif., only steps from where police had set up a command center.

"He said four or five times that he didn't have a problem with us, he just wanted to clear his name," Jim Reynolds said. "He said, 'I don't have a problem with you, so I'm not going to hurt you.'"

Dorner tied their arms and put pillowcases over their heads before fleeing in their purple Nissan, the couple said.

Before he fled, the couple said Dorner told them that he had been watching them before he took over their cabin. Dorner told the couple he could tell they were "hard working, good people."

"He had been watching us and saw me shoveling the snow Friday," Jim Reynolds said.

They say they may have left the cabin door unlocked and that could have been the reason Dorner was able to enter undetected.

Dorner remained "calm and meticulous" throughout the harrowing ordeal, the couple said.

The Reynolds walked into their cabin around noon Tuesday when they came face-to-face with Dorner. There was no question in their minds who he was -- the suspected cop killer at the center of one of the largest manhunts in recent memory.

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Water wars loom as the US runs dry

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Zuckerberg owns nearly a third of Facebook: US regulators

SAN FRANCISCO: Mark Zuckerberg's stake in Facebook has climbed to nearly 30 percent since the leading social network made its dismal stock market debut, according to a filing Wednesday with US regulators.

Zuckerberg owns 632.65 million Facebook shares as compared with the slightly more than 500 million he held in September when the stock's sagging price prompted a promise he would not sell any for at least a year.

Zuckerberg sold about 30 million shares when the Menlo Park, California-based social network made its stock market debut in May at an opening price of $38.

Shares slid to a low of $17.55 in September but have regained ground, trading at $28.04 at the close of trading on the Nasdaq exchange on Wednesday.

Securities and Exchange Commission filings show Zuckerberg has been building his stake Facebook, the potential of which he contends is underestimated by the market.

One SEC filing showed that Zuckerberg acquired 18 million Facebook shares in mid-December at a price of zero, indicating they were tied to his compensation as chief of the social network.

-AFP/gn

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Apple claims Einhorn lawsuit tries to hold investors 'hostage'

Apple accused an activist hedge fund manager of attempting to hold investors "hostage" in his effort to get the electronics giant to share more of its massive cash reserves with investors.

The charge came today in Apple's response to a lawsuit filed last week by Greenlight Capital, which asserts that the company needed to distribute preferred stock to current shareholders and that Apple had balked at the idea when it was first discussed. The filing comes a day after Apple CEO Tim Cook called the lawsuit a "silly sideshow."

"Shareholders should not be held hostage to plaintiffs' attempts to coerce Apple into an agreement that serves plaintiffs' financial interests," Apple said in its 27-page response (see below), adding that "the proposed injunction would harm the public interest."

Apple's latest proxy statement, which details items up for a vote at its February 27 shareholder meeting, includes a proposal that would eliminate "blank check" preferred stock. Greenlight Capital, which is run by the famed short seller David Einhorn, seeks an injunction to prevent Apple from bundling that provision with several other items. He wants each item to be voted on separately.

Apple claims in its response that the proposal does not constitute "improper bundling" because though the proxy identifies separate aspects of the proposal, shareholders are being asked only whether to amend the articles.

"There are numerous examples of proxy proposals that combine multiple changes to a single corporate document, including elimination of the 'blank check' authority to issue preferred stock," Apple stated.

Apple also called the suggestion of issuing an amended proxy "unworkable" because it would impose "millions of dollars" in administrative costs and delay a shareholder meeting.

"In short, plaintiffs cannot show any hardship of not obtaining injunctive relief, much less hardship that is greater than the financial harm to Apple and its shareholders of not having Proposal No. 2 put to a vote," Apple said in its filing, which noted that the proxy filing was submitted to the Securities and Exchange Commission for review but raised no red flags.

Apple Chief Financial Officer Peter Oppenheimer stated in a court declaration that during a conference call on February 6 Einhorn referred to the necessity of shareholder approval for issuance of new stock a "roadblock" that would just "make it harder." Einhorn said during the call that he wanted to "take the risk away," Oppenheimer said.

CNET has contacted Greenlight Capital for comment on the filing and will update this report when we learn more.

Einhorn has described Apple as a phenomenal company but one that's too cautious with its cash.

"It has sort of a mentality of a depression," Einhorn said during a CNBC interview last week. "In other words, people who have gone through traumas -- and Apple's gone through a couple traumas in its history -- they sometimes feel they can never have enough cash."

Speaking during a Goldman Sachs conference in San Francisco yesterday, Cook disputed those claims and said the company makes "bold and ambitious" bets on products while being conservative financially. He noted that Apple invested about $10 billion in capital expenditures last year and that it will spend a similar amount this year along with investing in retail stores, distribution, R&D, supply chain, and acquisitions.

"I don't know how a company with a Depression-era mindset would have done all those things," Cook said.

The company has defended its management of its cash reserves, which totaled more than $137 billion in cash and securities as of December, saying it has already delivered $10 billion of its plan to return $45 billion to shareholders over three years. It reinitiated a dividend last year and also has plans to buy back stock.

Apple Response to Einhorn suit by CNET News

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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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Ship Stranded: Love Boat to Horror Honeymoon

A Texas couple's fantasy wedding quickly turned into a nightmare honeymoon when the fire-damaged Carnival Cruise ship carrying them became stranded in the Gulf of Mexico.

Rob Mowlam, 37, and Stephanie Stevenson, 27, of Nederland, Texas, got married on the Carnival Triumph on Saturday. The four-day cruise was meant to be back to shore on Monday, but was left disabled by an engine fire on Sunday.

The ship is being slowly towed to shore and is expected to dock in Mobile, Ala., on Thursday if weather permits. The vessel is without air conditioning, many working toilets and some restaurant service. Passengers, many who are sleeping in tents on deck, have told ABC News the smell on the ship is foul.

That is the honeymoon setting for Mowlam and Stevenson.

"[Rob Mowlam] had been with his girlfriend, or fiance, for a long period of time and they just took the next step," Mowlam's brother James Mowlam III told ABCNews.com. "The captain is the king of the world when they're on the boat and he hitched them up."

James Mowlam said he was shocked when he heard about the stranded boat and the increasingly dire conditions on the ship.

"It is an atrocious scene to be subjected to," he said.

Mowlam said he has not been able to communicate with his brother, but that his father has had sporadic communication with him.

"It would be my guess that this would probably not be on anyone's great list of memorable wedding experiences," Mowlam said with a laugh. "Although, my mom told him that she was hoping they had a memorable wedding and I think this would classify as a memorable wedding experience."

Lt. Cmdr. Paul McConnell/U.S. Coast Guard/AP Photo

Carnival Cruise Ship Making Its Way to Port Watch Video

Carnival Cruise Ship Stranded for Third Day Watch Video

Carnival Cruise Ship Stranded off Yucatan Peninsula Watch Video

The bride's brother, Justin Davis, told ABCNews.com that his sister works for a doctor's office and the cruise was a gift from the doctor to the staff.

Davis has not been able to speak to Stevenson but said that her two young sons are being cared for by her mother. He said his sister is tough and he guesses she's probably not scared.

"She might be a little aggravated at the situation, but I'd say she's [probably] handling it really well," he said.

Others on the ship do not seem to be handling the situation so well.

Elderly and disabled passengers aboard the ship are struggling to cope with the worsening conditions, according to at least one passenger.

"Elderly and handicap are struggling, the smell is gross," passenger Ann Barlow text-messaged ABC News overnight. "Our room is leaking sewage."

The head of Carnival Cruise Lines said the British-U.S.-owned company was working hard to ensure the thousands of passengers stranded on the disabled ship were as comfortable as possible while the vessel was being towed to a port in Alabama.

"I need to apologize to our guests and to our families that have been affected by a very difficult situation," Carnival Cruise Lines president and CEO Gerry Cahill said at a news conference Tuesday evening.

It was the first time since a fire erupted in Triumph's engine room Sunday, knocking out its four engines, that a company representative had spoken publicly. The Triumph, with roughly 4,200 people on board, was left bobbing like a 100,000-ton cork for more than 24 hours. Giant sea-faring tugboats then hooked up to the ship and began towing the nearly 900-foot-long ship to land.

Carnival spokeswoman Joyce Oliva told The Associated Press Tuesday that a passenger with a pre-existing medical condition was taken off the ship as a precaution. Everyone else will likely have to weather conditions such as scarce running water, no air conditioning and long lines for food.

Back on land, passenger Barlow's 11-year-old twins told ABC News Tuesday they are worried as more passengers continue to talk about living with limited power and sanitation.

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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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Shatner: J.J. Abrams a 'pig' for taking on 'Star Wars'

William Shatner speaks to Movie Fanatic.

(Credit:
Video screenshot by Amanda Kooser/CNET)

J.J. Abrams is a busy man. The director who breathed new life into the "Star Trek" film franchise recently agreed to helm the new "Star Wars" movie. This may have fueled geeky fever dreams of crossover "Star Trek"/"Star Wars" projects, but it also led to some head-scratching. Does Abrams really have time to head up two major sci-fi film series?

"Star Trek" did have Abrams first. His sudden commitment to "Star Wars" may have left a few Trekkies feeling like they've gotten involved in an unexpected cinematic menage a trois. That's why I have some sympathy for William Shatner's recent comments to Movie Fanatic.

When asked to share his thoughts on Abrams adding "Star Wars" to his resume, Shatner said, "He's being a pig. He's collecting the two franchises and holding them close to his vest. And he's probably the most talented director of that ilk we have, but he's gone too far this time."

It sounds like we have a little bit of sci-fi smack talk going on here. Shatner goes on to say that he thinks of Abrams as a buddy and they've had sushi together. Then, things take a turn toward the heart of the matter. Shatner says he needs to have another talk with Abrams about his foolhardiness in not employing Shatner for either franchise.

We all know Shatner has a sense of humor, but his body language and tone come across as pretty serious in the video of the interview. It looks like he's not satisfied with just doing Priceline commercials anymore. I'm trying to imagine what role he would play in "Star Wars." Darth Tiberius, anyone?

(Via GeekTyrant)

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