//////////////////////////May your RetirementBe all you planned it to be,May you enjoy every momentOf being carefree
//////////////////////
Mountains of Evidence Suggest Human Evolution Had Rocky Start
By Dave Mosher, LiveScience Staff Writer
posted: 19 December 2007 04:13 pm ET
Share this story
var URI = escape(document.URL);
var url = escape('/history/071219-tectonic-evolution.html');
var cap = escape('');
var t1 = $('headline').getElementsByTagName("h1");
var t2 = $('headline').getElementsByTagName("h2");
if(t1.length >= 1 t2.length >= 1){
var t = (t1.length >= 1)? t1[0].innerHTML : t2[0].innerHTML;
var title = escape(t);
var str = 'url='+URI+'&title='+title;
//delicious//
document.write('');
document.write('');
document.write('');
document.write('');
//dig//
document.write('');
document.write('');
document.write('');
docu
Geology may be a long-overlooked, major factor that created conditions favoring the evolution of modern humans.
That's the conclusion of geologists at the University of Utah, who detail their findings in next month's issue of the journal Geotimes.
It's fairly well-established that changing climate, and thus vegetation, in East Africa spurred human evolution, but there has been no agreement about what exactly caused that change, said Royhan Gani
He thinks the riddle's answer is in rocks, and how big slabs of it move — altering continents and building mountains — by a process called tectonics.
"The idea of tectonics influencing evolution has been discussed since at least 1983, but no one's brought it to the foreground," said Gani, who co-authored the study with his wife, Nahid Gani.
Rock pushups
The evidence the couple studied was in "the Wall of Africa," a chain of highland rocks which extends for almost 3,700 miles (5,950 kilometers) from Sudan to South Africa. Two chunks of Earth's crust moving apart created this expansive feature.
"You get volcanism, but mostly an upwelling of magma pushing on the crust from below," Royhan Gani said. He compared the action to stretching plastic over a water spout: Where there are weaknesses in the film, the water pushes out bubbles.
In an Ethiopian stretch of the wall, the Ganis painstakingly mapped out the subsurface rock to show at least 3,200 feet (1 kilometer) of uplift happened between 3 million and 6 million years ago, creating valleys and basins.
This local and drastic "superplume" of tectonic activity caused the region's climatic to change, Royhan Gani said.
"These plateaus rose up and cut off much of Africa from wet Indian Ocean weather, sort of like the Rocky Mountains cut off Pacific [Ocean] air," he said. "That eventually dried up jungles into savanna and woodland."
Evicted ancestors
Gani said anthropologists found the new work compelling.
"Essentially, our ancestors were kicked out of trees and evolved full bipedalism," or walking and running on two feet, he told LiveScience. "They had to adapt to an environment with fewer and shorter trees and more spread-out food sources."
They also had to avoid being eaten.
"Some people argue running is a major reason our ancestors survived," he said. "They couldn't fight most predators face-to-face, so they fled."
Fossils indicate one of the first fully bipedal early humans, Australopithecus anamensis, emerged about 4.1 million years ago near the region the Ganis studied — placing it smack-dab in the middle of the jungle-to-savanna change.
In the future, Gani hopes to further investigate just how much tectonic activity accounts for the appearance of such early humans.
"It all happened within the right
Mountains of Evidence Suggest Human Evolution Had Rocky Start
By Dave Mosher, LiveScience Staff Writer
posted: 19 December 2007 04:13 pm ET
Share this story
var URI = escape(document.URL);
var url = escape('/history/071219-tectonic-evolution.html');
var cap = escape('');
var t1 = $('headline').getElementsByTagName("h1");
var t2 = $('headline').getElementsByTagName("h2");
if(t1.length >= 1 t2.length >= 1){
var t = (t1.length >= 1)? t1[0].innerHTML : t2[0].innerHTML;
var title = escape(t);
var str = 'url='+URI+'&title='+title;
//delicious//
document.write('');
document.write('');
document.write('');
document.write('');
//dig//
document.write('');
document.write('');
document.write('');
docu
Geology may be a long-overlooked, major factor that created conditions favoring the evolution of modern humans.
That's the conclusion of geologists at the University of Utah, who detail their findings in next month's issue of the journal Geotimes.
It's fairly well-established that changing climate, and thus vegetation, in East Africa spurred human evolution, but there has been no agreement about what exactly caused that change, said Royhan Gani
He thinks the riddle's answer is in rocks, and how big slabs of it move — altering continents and building mountains — by a process called tectonics.
"The idea of tectonics influencing evolution has been discussed since at least 1983, but no one's brought it to the foreground," said Gani, who co-authored the study with his wife, Nahid Gani.
Rock pushups
The evidence the couple studied was in "the Wall of Africa," a chain of highland rocks which extends for almost 3,700 miles (5,950 kilometers) from Sudan to South Africa. Two chunks of Earth's crust moving apart created this expansive feature.
"You get volcanism, but mostly an upwelling of magma pushing on the crust from below," Royhan Gani said. He compared the action to stretching plastic over a water spout: Where there are weaknesses in the film, the water pushes out bubbles.
In an Ethiopian stretch of the wall, the Ganis painstakingly mapped out the subsurface rock to show at least 3,200 feet (1 kilometer) of uplift happened between 3 million and 6 million years ago, creating valleys and basins.
This local and drastic "superplume" of tectonic activity caused the region's climatic to change, Royhan Gani said.
"These plateaus rose up and cut off much of Africa from wet Indian Ocean weather, sort of like the Rocky Mountains cut off Pacific [Ocean] air," he said. "That eventually dried up jungles into savanna and woodland."
Evicted ancestors
Gani said anthropologists found the new work compelling.
"Essentially, our ancestors were kicked out of trees and evolved full bipedalism," or walking and running on two feet, he told LiveScience. "They had to adapt to an environment with fewer and shorter trees and more spread-out food sources."
They also had to avoid being eaten.
"Some people argue running is a major reason our ancestors survived," he said. "They couldn't fight most predators face-to-face, so they fled."
Fossils indicate one of the first fully bipedal early humans, Australopithecus anamensis, emerged about 4.1 million years ago near the region the Ganis studied — placing it smack-dab in the middle of the jungle-to-savanna change.
In the future, Gani hopes to further investigate just how much tectonic activity accounts for the appearance of such early humans.
"It all happened within the right
///////////////////////NATURAL CAESARIAN
Search this site
In this section
Who was Anatole?
A different kind of love
Perceived neglect
First person
'I've had a glimpse of who I used to be'
'Darling, I'm just off to my teepee'
We're living longer than ever, but are more scared of ageing - why?
Living with teenagers
Family forum
Family life
Personal shopper, Annalisa Barbieri
Family life
Sleep talk
If I had the time ...
If I had the time ...
Every bit as magicalA British doctor is challenging convention to pioneer the 'natural' caesarean. Joanna Moorhead watched one baby's slow and gentle arrival Saturday December 3, 2005The Guardian
The scent of lavender fills the air and classical music is playing quietly. On the bed, Jax Martin-Betts, 42, is calm, focused and in control. With the birth of her second child just minutes away, the midwife, Jenny Smith, is giving her a massage. Her husband, Teady McErlean, is whispering words of encouragement: just a tiny bit longer, and our baby will be in our arms!
It could be a natural birth at any maternity unit in Britain, but we are in an operating theatre at Queen Charlotte's and Chelsea hospital in west London, and the birth we are about to witness sounds a contradiction in terms: a "natural" caesarean section.
Article continues
var setIframeSrcCallback =
function( hasVideo ) {
var adSrc = "http://ads.guardian.co.uk/html.ng/Params.richmedia=yes&spacedesc=mpu&site=Guardian&navsection=7365§ion=117420&country=gbr®ion=eng&city=brighton&bandwidth=broadband&rand=3925354&tile=3925354";
if(hasVideo) {
adSrc += "&system=video";
}
document.getElementById( 'frameId406515' ).src = adSrc;
};
if( 'function' == typeof addOnLoadCallback ) {
addOnLoadCallback( setIframeSrcCallback );
} else {
setIframeSrcCallback(false);
}
Jax has been on the theatre table for half an hour, and the obstetrician, Professor Nick Fisk, has almost completed the incisions through her abdominal wall and into her uterus. "OK, the baby is about to be born," he says. "Let's prop you up so you can see him coming out."
Smith removes the blue drape between Jax's head and her belly, and the head of the bed is lifted to give Jax a clear view. Fisk cuts into the amniotic sac and a fountain of fluid rises into the air before he rummages around to locate the baby's head. In a few seconds it comes into view, covered with the milky-white vernix that has protected it in the womb. For the next few moments, the atmosphere in the theatre is electric: Jax and Teady gasp in wonder at their new son, who is now looking around, although his lower body and legs are still inside his mother's uterus.
This groundbreaking approach to surgical delivery - Fisk calls it a "skin-to-skin caesarean", or "walking the baby out" - has been pioneered by him partly in response to the rising caesarean rate, which according to recent statistics reached a new high at 22.7% (of deliveries in England, 2003-04). "Whatever your view on caesareans, for some women it's always going to be the safest choice," he explains. "And while couples having normal deliveries have been given more and more opportunities to be fully involved in childbirth, very little has been done to see how we could make the experience more meaningful for those having caesareans."
As Fisk started to examine the conventions of surgical delivery, he was struck by how easily they could be challenged. Why, for example, did they need to be done so quickly, when slowing them down would give the parents more chance to participate in their child's delivery and might give the baby a gentler experience of coming into the world? Why, too, was it so important for the parents to be screened off from the mother's abdomen? And was it really essential for the baby to be whisked off for an immediate medical examination, rather than delivered into the arms of his mother?
"What I realised was that caesareans were done a certain way because they've always been done a certain way, but in fact they can be done differently - and in a way that parents love," says Fisk. Other doctors are sometimes shocked when they hear what he is doing. "They say, but surely you have to get the baby out fast so she can get oxygen straight away? And I say, when the baby is being born she's still attached to the umbilical cord and is still getting oxygen from the placenta. Caesarean birth can be gentle, just as vaginal birth can be gentle.
"Obstetricians are too hung up on getting from the point of incision to the birth of the baby as quickly as possible: that's been the benchmark of a skilled surgeon. But I'm challenging that because, from the baby's and from the parents' point of view, it's not very helpful.
"There's also a view that because the baby's chest hasn't been squeezed going through the birth canal, there are greater risks of breathing difficulties. But by leaving the baby's body inside the uterus for longer once the head is out, the body is squeezed and you see the lung liquid coming out of the baby's nose. Unless there are other risk factors, I've never known a baby born by my method to have problems - going straight onto the mother's chest helps regulate breathing."
Smith, who works closely with Fisk, says it's a hit with parents. "They feel more involved, which gives them a better start to family life. Breastfeeding is easier to establish, and you can see how much calmer the baby is."
For Jax, the birth of Finn - who weighed 3kg 25g (7lbs 3oz) - was "spellbinding".
"I had an emergency caesarean last time around. I'd wanted a natural water birth, but for some women it just doesn't work. This was every bit as magical: seeing Finn there in my tummy was a sight I'll savour for the rest of my life."
How the baby Finn is bornMinute by minute
09.24 Our first sight of baby Finn comes as Fisk gently lifts his head through the incision in Jax's abdomen. In a normal caesarean the baby would be lifted clear of the uterus immediately and the umbilical cord clamped and cut within seconds. The skin-to-skin caesarean gives the baby an experience of birth that is closer to a vaginal delivery. Instead of being pulled out quickly, Finn's emergence into the world is slow and calm, and the cord remains attached for some moments. His body is being squeezed slightly by being still inside the uterus, which helps drain fluid from the lungs.
09.26 Fisk begins to lift Finn up out of the uterus. In a normal caesarean the focus would now be on the baby's ability to breathe unaided, as the umbilical cord would already have been cut. But in the skin-to-skin caesarean the cord is left intact for several minutes during the delivery, so the baby is still receiving oxygenated blood from the placenta. At this point, the birth has been so gentle that Finn still seems to be asleep. Instead of being pulled quickly out of his mother, Finn is able to acclimatise slowly to his new surroundings.
09.27 Finn is now beginning to make tiny spluttering noises and is becoming aware of the fact that his surroundings have changed dramatically. At this moment, though, he is literally suspended between his old life in Jax's uterus and his new life in the outside world. His upper torso is outside his mother, but his lower body and legs are still folded inside the womb. Officially speaking Finn is not yet born, as it is only when his body has fully emerged that he is deemed to be an independent being. Jax now has a clear view of Finn as his head is lifted up.
09.28 The moment of birth, as Fisk lifts Finn clear of Jax's body. He will now hand him to Smith, centre, who will put him onto Jax's chest. Keeping the operation site sterile is a crucial consideration in the skin-to-skin caesarean, and Jax and Teady are warned not to try to touch their baby until he has been handed out of the sterile zone by Fisk. Finn is now moving his arms around and his breathing is clearly audible. Babies born by caesarean are often crying at this point - which is traditionally welcomed as a sign that they're breathing well.
09.29 Within seconds, Finn is placed on his mother's chest for a cuddle. Studies show immediate skin-to-skin contact results in a baby who is less likely to cry, has a more stable temperature, is more able to regulate his own breathing and has better blood sugar levels. In a normal caesarean, Finn would now be on a resuscitaire table, crying and throwing out his arms and legs. The skin-to-skin approach means he can acclimatise slowly to the world beyond the womb: so far, he has not cried. Lying on Jax's chest, hearing her heartbeat and voice, he is a picture of contentment.
////////////////////////////////RELATIONSHIPS How to stay connected in a conversationWhen talking with another person, a great way to stay connected is to focus on just one eye, rather than trying to look at both eyes and shifting your attention back and forth.
////////////////////////2 HR PENANCE FOR SIAZ NRI LBL CRSS
////////////////////////Fossil hunters have discovered the remains of a small deer-like animal, the earliest ancestor of the modern whale and a long-sought 'missing link' in the evolution of ancient land mammals into modern cetaceans.##
//////////////////////
Health News Article
Short legs 'liver disease risk'
Researchers in the UK have said that women who have short legs could have a higher risk of liver disease.
The study examined 4,300 women aged between 60 and 79. The research team selected participants from the British Women's Health and Heart Study at random, who came from 43 towns around Britain.The Bristol University team published details of the connection between leg length and liver disease in the Journal of Epidemiology and Community Health.
They took measurements of height and leg length. The team also measured the levels of four liver enzymes - ALT, GGT, ALP and AST - from blood samples. The enzymes show how the liver is functioning and display signs of damage.They found the women with longer legs had lower levels of three of the liver enzymes, while women with shorter legs had higher levels of all four enzymes. The team's head, Dr Abigail Fraser, said that the research could be link to "upbringing"."Our interpretation of the results is that childhood exposures, such as good nutrition that influence growth patterns also influence liver development and therefore levels of liver enzymes in adulthood and/or the propensity for liver damage," the team stated.
The team also said that taller women could have larger livers, which might decrease enzyme levels "so ensuring that the liver is able to withstand chemical onslaught more effectively."A spokesperson from the British Liver Trust said the study was intriguing and called for further research.
Health News Article
Short legs 'liver disease risk'
Researchers in the UK have said that women who have short legs could have a higher risk of liver disease.
The study examined 4,300 women aged between 60 and 79. The research team selected participants from the British Women's Health and Heart Study at random, who came from 43 towns around Britain.The Bristol University team published details of the connection between leg length and liver disease in the Journal of Epidemiology and Community Health.
They took measurements of height and leg length. The team also measured the levels of four liver enzymes - ALT, GGT, ALP and AST - from blood samples. The enzymes show how the liver is functioning and display signs of damage.They found the women with longer legs had lower levels of three of the liver enzymes, while women with shorter legs had higher levels of all four enzymes. The team's head, Dr Abigail Fraser, said that the research could be link to "upbringing"."Our interpretation of the results is that childhood exposures, such as good nutrition that influence growth patterns also influence liver development and therefore levels of liver enzymes in adulthood and/or the propensity for liver damage," the team stated.
The team also said that taller women could have larger livers, which might decrease enzyme levels "so ensuring that the liver is able to withstand chemical onslaught more effectively."A spokesperson from the British Liver Trust said the study was intriguing and called for further research.
///////////////////////
No comments:
Post a Comment