Tuesday, 27 June 2017

Chimps' strength secrets explained


ChimpsImage copyrightAFP
Image captionChimps do appear to be stronger than us, but not by as much as we often think
The greater strength of chimpanzees, relative to humans, may have been explained by American scientists.
A study suggests the difference is mostly due to a higher proportion in chimps of a muscle fibre type involved in powerful, rapid movements.
The findings do not support previous work suggesting mechanical aspects of chimp muscles are responsible.
But the difference in chimp-human muscle performance is more modest than sometimes depicted in popular culture.
In the 1920s, anecdotal evidence along with investigations by the biologist John Bauman, helped feed a perception that chimps were between four and eight times stronger than an adult human.
But subsequent studies failed to replicate these figures, as later researchers found that chimps did not greatly outperform adult males when given physical tasks.
Writing in PNAS journal, Dr Matthew C O'Neill, from the University of Arizona College of Medicine-Phoenix, and colleagues reviewed the literature on chimp muscle performance and found that, on average, they are 1.5 times more powerful than humans in pulling and jumping tasks.

Puny human?

"My sense of it was there had not been a critical review of all the experiments that had been done up until our study," Dr O'Neill told BBC News.
"It was something we needed to do before getting into the substance of our paper."
According to ideas put forward in previous work, the difference might be accounted for if chimpanzee muscles were able to generate more force per area, or, alternatively, if chimp muscle was able to shorten faster than human muscle - helping increase its power output.
Dr O'Neill and his colleagues set out to test these ideas and others, by directly measuring the properties of muscle fibres taken from chimps that had been frozen after death.
"We really wanted to get a handle on the basic properties of chimpanzee skeletal muscle - and find out whether they were different from those of human muscle," he explained.
Along with cardiac muscle and smooth muscle, skeletal muscle is one of the three main muscle types, and is mostly found attached to bones via the bundles of collagen known as tendons.
"What we found was that there was really no difference in the fundamental contractile properties of chimp muscle fibres and human muscle fibres, for any of the individual fibres," Dr O'Neill said.
However, they did find key differences in the length of the fibres - chimp muscle fibres tend to be longer than corresponding ones in humans - and in the distribution of different muscle fibre types.

Fast vs slow

Chimps possess about twice the amount of "fast-twitch" muscle fibre. This type of fibre contracts quickly and is useful for rapid movements such as sprinting. But fast-twitch fibres have a downside: they quickly tire.
By contrast, corresponding human muscles are dominated by "slow-twitch" muscle fibres, which contract more slowly, but keep going for longer. They are useful for activities that require endurance.
Computer simulations suggest that these differences increase the maximum dynamic force and power-producing capacity of chimp skeletal muscle by a factor of 1.35 compared with a human muscle of a similar size. The 1.35 figure corresponds well with the 1.5 times figure reached by reviewing the scientific literature.
The team members suggest this may reflect chimps' greater reliance on tree climbing and suspension for their survival.
In fact, the dominance of fast-twitch fibres appears to be a default setting in mammals, from mice to horses. The only animal the researchers could find which mirrored the slow-twitch fibre pattern seen in humans was the slow loris - a sluggish nocturnal primate indigenous to southern Asia.
To the scientists, this was something that probably evolved in the lineage leading to humans after its divergence from the ancestral line leading to chimpanzees.
The shorter muscle fibres and greater percentage of slow-twitch fibres in humans may have enhanced our endurance capabilities. These changes may coincide with evolutionary shifts in human locomotion, as human ancestors became better at upright walking and were required to travel longer distances.
But if this is true, it remains unclear why the dominance of slow-twitch fibres extends to the upper body as well as the lower. It may be that the distribution of different muscle types across the body is dialled up or down by the regulation of different genes. But Dr O'Neill says that only more research can answer that question.
Follow Paul on Twitter.

1 injured, manhunt ongoing after stabbing incident at Toronto shopping mall


1 injured, manhunt ongoing after stabbing incident at Toronto shopping mall
A teenager has been seriously injured in a stabbing incident inside the Yorkdale shopping center in Toronto, Canada, local media report, citing police. Four suspects are believed to be on the loose, possibly "still in the mall."
The teenager, whose injuries are described as "very serious," was stabbed on Monday evening at the entrance to the cinema inside the busy mall, local CTV News reported, citing police.
"There are several units on the scene searching in and around the entire area. It is unknown if the suspects are still in the mall," CP24 reported Toronto police spokesperson Allyson Douglas-Cook as saying.
Police are searching for four suspects, at least two of whom have been described as black males. Another man and woman are believed to have been involved in the incident, the police official said.
There have been no reports of other injuries.
The shopping center remains open, but police are advising people to avoid it as they search for suspects, according to CTV news.

US threats to Syria’s legitimate government unacceptable – Kremlin


US threats to Syria’s legitimate government unacceptable – Kremlin
Russia has slammed Washington’s threats against the Syrian government following a recent White House statement alleging that President Bashar Assad’s forces are preparing to use chemical weapons.
“I am not aware of any information or threat of using chemical weapons,” Russian President Vladimir Putin’s spokesman Dmitry Peskov told journalists on Tuesday.
DETAILS TO FOLLOW

Sunday, 25 June 2017

Newcastle Eid celebration: Six hurt as car hits crowd


Media caption"Everybody was in a panic"
Six people, including three children, were injured when a car mounted a kerb and ploughed into a crowd of people outside a sports centre in Newcastle.
It happened outside Westgate Sports Centre where an event was taking place to celebrate the end of Ramadan.
Two children are in intensive care and one adult is seriously injured.
Northumbria Police said the incident was not believed to be terrorism-related. A 42-year-old woman was arrested and is in custody.
The remaining injured are believed to have serious but non-life threatening injuries, officers said.
The woman who was arrested had been celebrating Eid with her family and hundreds of others.
Westgate Road
Image captionEmergency services included six ambulances, two paramedic rapid response vehicles and the air ambulance
No-one else was being sought. Extra patrols were in the area to reassure communities, police said.
One eyewitness said: "From what I understand, [a woman who had been at prayer] was about to leave in her car and I believe she lost control.
"I ran up straight away because everyone was moving in on all the injured, trying to put water in their mouths.
"The parents of the kids were there. I had to sort of try and calm them down just to tell them the ambulance is there and they will take care of it; they know what they're doing."

'Prayers for recovery'

Emergency services included six ambulances, two paramedic rapid response vehicles and the air ambulance.
Scene at Westgate Sports Centre
Image captionA 42-year-old woman is being held in police custody
In a statement, the nearby Newcastle Central Mosque said: "We pray and hope that all those affected recover soon fully.
"We thank the emergency medical services, the police and over 100 volunteers from the mosque for their quick response to the incident.
"We urge everyone to please pray for all those affected."
Chi Onwurah, Labour MP for Newcastle Central, tweeted: "So sad, I was at the prayers earlier & there were so much joy & unity. Thinking of those affected by what I am told was terrible accident."
Scene at Westgate sports centre
Image captionPeople at the scene created a human chain so emergency services could help the injured

'Everyone locked arms' - medical student Ahmad Ali

We were here for Eid. Everyone had just finished praying. The imam had finished his speech and everyone was talking to their families and getting some food.
Then we heard a commotion and screaming.
I ran up to the hill. A man got out of the passenger side. He seemed distraught.
Someone was trapped under the car and then everyone just pushed the car so they were free.
They were two children there, one of them - he was a boy about eight - was really badly injured,
There were about five doctors there so he had a lot of medical attention. We checked to see he had a pulse.
Everyone locked arms so there was a ring of locked arms around the injured people so they had space and the ambulances could get to them.
Everyone was distraught. I am very grateful it's not an attack.
It's very shocking to see a child injured like that. We are all hoping that he is fine, I just want to hear that.

Scene at Westgate Sports Centre
Abdul Mahdoul, who was at the event, said: "We were wishing everyone happy Eid and suddenly we heard a lot of shouting and screaming. We didn't know what it was.
"People were panicking. The police did a great job to calm the situation down.
"It was a very happy atmosphere beforehand, but afterwards just chaos. I just wish for the people to recover very quickly."
Abdul Mahdoul
Image captionAbdul Mahdoul said a "very happy atmosphere" turned into "chaos"
Councillor Dipu Ahad said: "I hope there are no fatalities and my thoughts are with their families and other members who have been affected.
"We saw people crying and sobbing, it was like what you see in a horror movie, people were crying on the street, in corners.
"It was a real sad situation to see this and I think people were in confusion about what really happened.
"I had tears in my own eyes - it was a day of celebration for Muslims and others as well and it's a very sad situation and I hope this never happens again."
Scene next to Westgate Sports Centre
Image captionWestgate road has reopened following earlier closures in both directions

UN: Starvation threatens 2 million in drought-hit Somalia

Fri Sep 13, 2019 01:44PM [Updated: Fri Sep 13, 2019 01:52PM ] Home Africa Somalia A newly arrived woman fleeing from the drought...