Cosmic Impact May Have Caused Prehistoric ‘Big Freeze’

Posted September 3rd, 2013 at 7:39 pm (UTC+0)
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Asteroid impacting Earth (NASA)

Artist rendering of an asteroid impacting Earth (NASA)

Scientists say they may have found a link between a dramatic climate shift nearly 13,000 years ago and an asteroid or comet that struck the Canadian province of Quebec.

Researchers at Dartmouth College say the comet/asteroid strike took place at the beginning of a global cooling event known as the Younger Dryas stadial or the Big Freeze.

It was an abrupt, geologically brief period of colder and dryer climatic conditions that lasted about 1,300 years, and had far-reaching effects on both humans and animals.

Big animals, such as mastodons, camels, giant ground sloths, and saber-toothed cats all vanished from North America during this cool period.

The humans who lived in North America at the time, known as Clovis people, normally hunted the large animals, but after this  extinction they set aside their heavy hunting weapons and adopt a hunter-gatherer lifestyle, living off  a diet of roots, berries, and smaller game.

Paleo-Indians (includes Clovis People) are first people to entered and inhabit the Americas shown hunting a glyptodont (armadillo ancestor (Heinrich Harder via Wikimedia Commons)

Paleo-Indians (includes Clovis People), shown hunting a glyptodont (armadillo ancestor ), were the first humans to enter and inhabit the Americas.(Heinrich Harder via Wikimedia Commons)

“The Younger Dryas cooling is a very intriguing event that impacted human history in a profound manner,” said Mukul Sharma, one of the study authors and a professor in Dartmouth’s Department of Earth Sciences. “Environmental stresses may also have caused Natufians (a culture that existed between 13,000 and 9,000 BC) in the Near East to settle down for the first time and pursue agriculture.”

While the  environmental changes brought on by the Younger Dryas haven’t been disputed, the causes of it have been.

Scientists have long thought the Younger Dryas period was caused by a surge of meltwater from the North American ice sheet from the last glacial period.

According to this theory,  a great amount of fresh water from melted ice collected behind an ice dam, which suddenly burst, dumping  huge quantities of freshwater into the Atlantic Ocean. The sudden water surge was thought to have shut down the ocean currents that usually move ocean water from the tropics northward.  The lack of the usual northbound stream of warmer water then left the climate cold and dry throughout the Younger Dryas period.

Sharma said that while his team’s research shows conclusive proof that an asteroid/comet impacted over the North American Ice Sheet around the beginning of the Younger Dryas period, further investigation will need to determine whether the cosmic event is linked to the Big Freeze.

The researchers  found evidence of a connection in droplets of solidified molten rock  thrown off from a celestial object during impact. The spherules were collected from boundary layers of sediment from the beginning of the Big Freeze at sites in Pennsylvania and New Jersey.

The high temperatures of the meteorite impact 12,900 years ago produced mm-sized spherules of melted glass with the mullite and corundum crystal structure shown here. (Mukul Sharma)

The high temperatures of the meteorite impact 12,900 years ago produced mm-sized spherules of melted glass with the mullite and corundum crystal structure shown here. (Mukul Sharma)

There is a 4-kilometer-wide impact crater in Quebec, known as the Corossol crater, where researchers believe a meteor or comet hit. The New Jersey and Pennsylvania spherules are identical to rock found in southern Quebec, but geochemical and mineralogical research indicates they are not a perfect match.

“What is exciting in our paper is that we have for the first time narrowed down the region where a Younger Dryas impact did take place, even though we have not yet found its crater,” Sharma said in a press release.

Sharma also pointed out that the extensive environmental changes of the Younger Dryas might be the result of not just one but multiple concurrent asteroid/comet impacts.

The study, funded by the National Science Foundation, will be published in the Proceedings of the National Academy of Sciences (PNAS).

Whales Get Sunburned Too

Posted August 30th, 2013 at 5:59 pm (UTC+0)

The sun blistered skin of a blue whale photographed in the Gulf of California. (AP)

The sun blistered skin of a blue whale photographed in the Gulf of California. (AP)

Anyone who has experienced the searing pain of sunburn knows that too much sun can wreak havoc on your skin.

Turns out that our fellow mammal, the whale, can also tan and get sunburn.

A study published in ‘Scientific Reports, from the publishers of the journal Nature, reveals the sun produces an increase in pigment in the skin of whales.

Research by an international team of scientists showed that, not only do some species of whales get dark tans when they’re exposed to the sun, but they also suffer harm to their skin’s DNA.  And just like us, whales can wind up with damaged skin cells as they get older.

Marine biologists at Universities in Mexico noticed that an increasing number of whales in their area had blistered skin, so they called in researchers from the UK’s Newcastle University. The British scientists analyzed skin samples from three types of whales, the blue whale, sperm and fin whale.

They worked with their Mexican colleagues along with other marine biologists from Canada’s Trent University, to study changes in whale skin after the gargantuan creatures made their annual migration to sunnier climes.

Taking a skin biopsy from a blue whale (Newcastle University, UK.)

Taking a skin biopsy from a blue whale (Newcastle University, UK.)

“Whales can be thought of as the UV barometers of the sea. It’s important that we study them as they are some of the longest living sea creatures and are sensitive to changes in their environment so they reflect the health of the ocean,” said Mark Birch-Machin, a senior author of the study and a professor of molecular dermatology at Newcastle University.

The Mexican and Canadian scientists took skin samples off the backs of the three species of whales over a three-year period between February and April, when the whales make their annual move to the sunny Gulf of California, located along the northwest coast of Mexico.

The biggest species the researchers studied was the pale-skinned blue whale.

The  team found a seasonal change with the blue whale during its migration time.  They noticed that the whale’s skin pigment increased and that its skin cell’s mitochondria – a cell’s power plant – were also experiencing some DNA damage.  They say that the internal mitochondrial damage that was discovered was caused by UV exposure and was similar to what could be found in the sunburned human skin.

A pod of sperm whales (Gabriel Barathieu via Creative Commons/Flickr)

A pod of sperm whales (Gabriel Barathieu via Creative Commons/Flickr)

Another species, sperm whales have a darker pigmentation than their blue whale relatives.  While they too take part in the annual February to April trek to the Gulf of California, the sperm whales have a different lifestyle than other whales. They spend a long time on the water’s surface which means they are exposed to more UV rays.

But the researchers found that by setting off a stress response in their genes, the sperm whales had developed a unique mechanism to protect themselves from harm caused by the sun.

“We saw for the first time evidence of genotoxic (a toxic agent that damages DNA molecules in genes) pathways being activated in the cells of the whales – this is similar to the damage response caused by free radicals in human skin which is our protective mechanism against sun damage,” said Amy Bowman, a researcher from Newcastle University.

The third species studied by the researchers was the fin whale, which compared to the blue and sperm whales, had the deepest pigmented skin.  Because of their darker skin color, the researchers discovered  the fin whale had the lowest number of sunburn lesions on their skin, which meant that they were more resistant to sun damage.

Fin whale (Ulrich Zink via Wikimedia Commons)

Fin whale (Ulrich Zink via Wikimedia Commons)

“We need to investigate further what is happening,” said Birch-Machin. “If we are already seeing blistered skin in the whales caused by UV damage, then we want to know whether this could develop into skin cancer and therefore serve as an early warning system.

The research team noted that their findings serve as a reminder that changing climatic conditions are affecting every creature on the planet.

Scientists Say They’ve Confirmed Existence of New Chemical Element

Posted August 28th, 2013 at 7:30 pm (UTC+0)

Period table of elements ( Le Van Han Cédric via Wikimedia Commons)

Students heading back to school for the new year might need to add a new element to their periodic table of elements in chemistry class.

Swedish scientists  say they have fresh evidence that confirms the existence of a previously unknown chemical element.

The new “super-heavy” element is listed as number 115 or Ununpentium (Uup) and has an atomic weight – the average mass of the element’s atom – of 289.

Element #115 was discovered in 2003 (reported in February 2004) by scientists at the Lawrence Livermore National Laboratory in California working with researchers from the Joint Institute for Nuclear Research in Russia (JINR).

This element, considered to be radioactive and classified as a metal, is artificially produced by bombarding atoms of americium-243 — an isotope of the element Americium (Am)  — with ions of a rare isotope calcium-48 using a device called a cyclotron.

Electron configuration of element #115 ununpentium (Greg Robson via Wikimedia Commons)

Electron configuration of element #115 ununpentium (Greg Robson via Wikimedia Commons)

Scientists say this  element probably won’t have any practical purposes, unlike others such as iron (Fe), oxygen (O) or even uranium (U) since it is  unstable and has a short half-life of about 220 milliseconds. An element’s half-life is the point in which the nucleus of an unstable atom loses energy to half its value.

Because of its unstable properties, scientists also say element #115 should not have any negative effects on human health or the environment.

Along with making observations of the new chemical element, the research team was also able to gain access to data that provides a deeper insight into the structure and properties of super-heavy atomic nuclei.

“This was a very successful experiment and is one of the most important in the field in recent years”, said Dirk Rudolph, professor nuclear physics at Lund University.

In creating the element, the researchers bombarded a thin film of americium with calcium ions which made it possible for them to measure photons in connection with the element’s alpha decay, which is a process that unstable atoms can use to become more stable.

During an alpha decay, the unstable atom’s nucleus discards two of its protons and two neutrons, creating  an “alpha particle” that has a composition identical to a helium nucleus.

diagram showing an alpha particle (α) being ejected from the nucleus of an atom. Protons are red and neutrons are blue.(Wikimedia Commons)

diagram showing an alpha particle (α) being ejected from the nucleus of an atom. Protons are red and neutrons are blue.(Wikimedia Commons)

Scientists have said element #115 alpha decays into element #113, dubbed ununtrium (Uut), which in turn decays into roentgenium (Rg) or element #111, which also doesn’t last too long either, with a half-life of about 26 seconds.

Ununpentium is a hybrid Greek and Latin word that loosely translates into one-one-five, the temporary name of element #115, which hasn’t been given an official name.

A committee of experts will first review the new findings  so that they can decide whether to recommend further experiments before acknowledging the discovery of element #115.

The team’s findings were published in the “The Physical Review Letters.”

Scientists Track Happiness with Cell Phones

Posted August 23rd, 2013 at 7:35 pm (UTC+0)

Jumping with happiness (Will Foster via Creative Commons/Flickr)

(Will Foster via Creative Commons/Flickr)

Every day it seems that people are coming up with new and innovative ways to use mobile devices like cell phones and smartphones.

Researchers at Princeton University are looking for new ways to measure a person’s sense of well-being with mobile devices.

To gain a better understanding of how cellphones and other mobile device can gauge our sense of happiness, the research team conducted a study that was published recently in the journal Demography.

To gather data for their study, the team created an application for mobile devices using the Android operating system.

Once the app was developed, the researchers invited people to download it and take part in their study. Over a three-week period, the research team was able to collect data from some 270 participants living in 13 countries.

Participants came not only from the United States, but also from other nations like Australia, Canada, China, France, Germany, Israel, Japan, Norway, South Korea, Spain, Sweden and the United Kingdom.

Over the course of the study, participants received occasional text questions from the researchers that asked “How happy are you”? Along with recording their response, the app used the mobile device’s built-in GPS to keep track of the participant’s location.

The study participants were asked to rate their current state of happiness on a scale of zero to five.

A mobile phone with android applications (Rafe Blandford via Creative Commons/Flickr)

A mobile phone with android applications (Rafe Blandford via Creative Commons/Flickr)

As they gathered data from the information collected through the application, the researchers then were able to create and fine-tune new methods that could help provide a better understanding of how our surroundings can influence our emotional well-being.

The researchers learned that mobile devices can provide an effective way to quickly grab information that, because of today’s active lifestyle, can be difficult to record.

Being able to quickly and spontaneously grab this info was something the researchers felt was important. They said feelings and emotions that were recorded as they were happening were most likely to be more honest and precise than using other methods like writing down how they felt on a piece of paper after the fact.

The study’s authors said that the mobile phone data gathering method allowed them to get around some of the drawbacks of traditional surveying methods, such as those  conducted at people’s homes, which are only able to record reactions in one fixed location.  But, people today are constantly on the move and the mobile device method is able to keep frequent track of data no matter where a participant happens to be.

The researchers noted that the focus of their research at the time of the study’s publication was more on learning more about the capabilities of mobile devices as a way to collect data, rather than coming up with general conclusions regarding the link between a person’s surroundings and their overall happiness.

Not so happy (John Verive via Creative Commons/Flickr)

(John Verive via Creative Commons/Flickr)

However, the research team was able to come up with some preliminary results on their measurement of happiness.

They found males were more inclined to indicate that they were less happy when they were further away from home. However, distance from home didn’t play much of a role in determining just how happy the females were.

Back in April, scientists from the University of Vermont and the MITRE Corporation made news when they announced their new method of gauging happiness through what people were tweeting via the social networking website Twitter.

Ancient Chinese Treatment Could Be Effective in Treating Spinal Cord Injuries

Posted August 20th, 2013 at 6:43 pm (UTC+0)

Different kinds of roots used to treat patients with Chinese herbal medicine on display at a Chinese pharmacy (Gary Kleemann via Creative Commons/Picasa)

Chinese herbal medicine at a Chinese pharmacy (Gary Kleemann via Creative Commons/Picasa)

Traditional Chinese herbal medicines have been used to treat a variety of ailments for centuries. Now a new study finds an ancient medicinal practice, called Ji-Sui-Kang (JSK), can improve locomotor function in rats with spinal cord injuries.

The researchers reported that after being treated with JSK, the injured rats showed decreased tissue damage and the structure of their neural cells was better preserved when compared to rats in a control group.

The data also showed that JSK treatment might reduce inflammation and cell death, as well as boost local oxygen supply in the affected area. After a while, the JSK appeared to restore function and promote tissue regeneration.

Those involved with the study say their work provides an important foundation for further study into the use of JSK therapy.

“A number of anecdotal reports from Chinese medicine practitioners indicate that treatment with a novel herbal formulation, JSK, for periods of one week or three months improved functional recovery,” said the study’s co-lead investigator Shucui Jiang, head of the Hamilton NeuroRestorative Group at McMaster University in Hamilton, Ontario, Canada.

Anterior view of a human spinal cord (John A Beal, Louisiana State University Health Sciences Center)

Anterior view of a human spinal cord (John A Beal, Louisiana State University Health Sciences Center)

For this study, the researchers divided their rat test subjects into two groups.  One group was treated with the herbal medicine treatment while the control group was given a saline solution. Treatment began immediately after spinal cord injury and the test period was 21 days.

The investigators reported that, within seven days of the start of their experiment, the hind limb locomotor function was significantly better in the group of rats treated with JSK as compared to the group that only got the saline.

Throughout the 21-day test period, the rats treated with JSK continued to display better motor function, appeared to support their weight better, and showed more coordinated movement than those in the control group. After examining microscopic samples of the spinal cord from rats in each group, the researchers found that the structure of the injured spinal cord of those treated with JSK was better preserved. Additionally, the size of the injured area was significantly reduced about a week after the injury.

Traditional Chinese medicine shop in Tsim Sha Tsui, Kowloon, Hong Kong (© Mailer Diablo via Wikimedia Commons)

Traditional Chinese medicine shop in Tsim Sha Tsui, Kowloon, Hong Kong (© Mailer Diablo via Wikimedia Commons)

“Our data suggest that JSK may enhance tissue recovery by reducing cell growth inhibitors and by promoting the proliferation of cells within the injured spinal cord,” said the other co-lead investigator Michel Rathbone, a professor at the Department of Medicine at McMaster University.

The researchers said their study suggests JSK treatment could help protect against further spinal cord injury caused by damage to local blood vessels.

Citing proprietary reasons, the authors of the study did not reveal the entire herbal composition of their JSK treatment. But, they did list some of the ingredients which included ginseng, rhizoma, glycyrrhizae radix, paeoniae alba radix and cinnamomi cortex.

Food Allergies Rise Worldwide

Posted August 17th, 2013 at 2:06 am (UTC+0)
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Some food types likely to cause allergic reactions - cheese, nuts, wine, fruit, and shellfish. (David Castor via Wikimedia Commons)

Some food types likely to cause allergic reactions – cheese, nuts, wine, fruit, and shellfish. (David Castor via Wikimedia Commons)

Earlier this month a 13-year-old California girl with an allergy to peanuts died in her father’s arms after unknowingly consuming a small amount of peanut butter in a snack she was eating.

The girl quickly spit out the small bit of peanut butter, but efforts to save her life, including multiple injections that should have brought her allergic reaction to a halt, were futile.

The teen’s death brings home the dangers faced by those with severe food allergies

The World Health Organization says food allergies appear to be on the rise in all industrialized nations and considers it an important health issue.  The Centers for Disease Control and Prevention conducted a study in 2008 that showed an 18 percent increase in the amount of children in the US with food allergies.

The current rise in food allergies has been particularly noticeable among young people 18 and under.

Dr. Melinda Braskett, Medical Director of the UCLA Food and Drug Allergy Care Center (UCLA Health)

Dr. Melinda Braskett, Medical Director of the UCLA Food and Drug Allergy Care Center (UCLA Health)

The number of people who die from  food allergies is low, but when a person with a severe food allergy consumes even a microscopic bit of that food, it can result in anaphylaxis,  an allergic reaction that can in some cases lead to death.

Dr. Melinda Braskett, medical director of the UCLA Food & Drug Allergy Care Center in California, refers to food allergies as misguided immune reactions to foods that can cause reproducible rapid reactions like rashes, swelling and breathing problems.

Along with peanuts, Braskett said milk, soy, eggs and wheat are the most common items to produce food allergies.

Many of those with dangerous allergies to certain foods notice the symptoms of the allergic reaction come on quickly and may start with relatively mild symptoms, but can quickly escalate into something more serious or even life threatening.

While the number of people with food allergies is growing, so far there are no clear answers as to why.

Braskett suspects the rise in food allergies may be linked to more people developing a wide range of allergies and that we’re becoming more allergic as a society.

Since people are generally cleaner than in times past, something she refers to as the “hygiene hypothesis” may play a role in triggering immune responses to a variety of items that may not have been a problem before.

(Mikael Häggström via Wikimedia Commons)

(Mikael Häggström via Wikimedia Commons)

Braskett noted that some people without food allergies might still have something called food intolerance which she said is broad and hard to define.

Someone with food intolerance may get a migraine headache, experience an outbreak of acne or bloating without any other symptoms after eating something like chocolate or foods with artificial coloring added. Getting indigestion after a spicy meal is also considered food intolerance.

If you suspect you have a food allergy, Dr. Braskett recommends seeing your doctor first.

Your doctor can help you determine if you actually have a food allergy and identify what you’re allergic to.  That way, a plan to manage your allergies can be developed.

Baskett advised keeping some antihistamines, like Benadryl, on hand in the event you accidentally eat something that causes an allergic reaction. Your doctor can determine what specific medications and dosages work best for you.

An EpiPen epinephrine autoinjector is used to avoid and treat anaphylaxis from a severe allergic reaction (Greg Friese via Creative Commons at Flickr)

An EpiPen epinephrine autoinjector is used to avoid and treat anaphylaxis from a severe allergic reaction (Greg Friese via Creative Commons at Flickr)

Sometimes though an allergic reaction can begin and advance so quickly that there may not be enough time for the antihistamines to work properly.  In that case, immediate emergency action will be needed.

Many people, who are subject to severe and potentially-deadly allergic reactions, carry an epinephrine autoinjector or pen.  This is a medical device that quickly provides the proper measured dose of epinephrine or adrenaline, which is a medication that avoids or treats anaphylactic shock.

If you do have a food allergy, the standard treatment is to avoid the foods you’re allergic to.  Braskett said to keep a close eye on the ingredients of the foods you eat to ensure they don’t contain any potentially harmful elements.

Braskett also recommends talking with family and friends about your allergies and getting their help and support.

Neanderthals Invented Leather Tool Still Used Today

Posted August 13th, 2013 at 6:06 pm (UTC+0)
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This image shows four views of the most complete lissoir found during excavations at the Neandertal site of Abri Peyrony. (Abri Peyrony & Pech-de-l'Azé I Projects)

Four views of the most complete lissoir found during excavations at the Neanderthal site of Abri Peyrony. (Abri Peyrony & Pech-de-l’Azé I Projects)

New evidence shows Neanderthals likely invented a type of hand tool that’s still being today by high-end leather workers.

Two international teams of researchers reached that conclusion after discovering remnants of  bone tools crafted by ancient man about 50,000 years ago.

The tools found at two  Paleolithic sites in southwest France were identified as a lissoir, or smoother. The tools are unlike anything found at similar archaeological sites. They were fashioned from deer ribs and have a polished tip that, when pressed against an animal hide, creates leather that is softer, polished and more water resistant.

“For now, the bone tools from these two sites are one of the better pieces of evidence we have for Neanderthals developing on their own a technology previously associated only with modern humans,” said Shannon McPherron of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

McxPherron, along with his colleague Michel Lenoir of the University of Bordeaux, found three of the bone tools while excavating the Abri Peyrony, also known as Haut de Combe-Capelle, archeological site. The first of the four bone tools was found  at another site called Pech-de-l’Azé I, by a second team led by Marie Soressi of Leiden University in The Netherlands.

“If Neanderthals developed this type of bone tool on their own, it is possible that modern humans then acquired this technology from Neanderthals,” said Soressi. “Modern humans seem to have entered Europe with pointed bone tools only and, soon after, started to make lissoirs. This is the first possible evidence for transmission from Neanderthals to our direct ancestors.”

Reconstruction of a Neanderthal male displayed at the Neanderthal Museum in Mettmann, Germany (Erich Ferdinand via Wikimedia Commons)

Reconstruction of a Neanderthal male displayed at the Neanderthal Museum in Mettmann, Germany (Erich Ferdinand via Wikimedia Commons)

However, the researchers  haven’t ruled out the possibility that the tools may instead show that modern humans arrived in Europe earlier than thought and began to impact Neanderthal behavior.

In order to resolve that conflict, scientists would need to find better preserved evidence of bone tools at additional excavation sites in central Europe.

The researchers aren’t sure how many Neanderthals created and used the tools or whether their use was widespread.

If the scientists hadn’t had experience working with later bone tools, they could have missed the first three bone tools  since they were  fragments less than a few centimeters long. The tools were also not something  archeologists normally look for in this time period.

“However, when you put these small fragments together and compare them with finds from later sites, the pattern in them is clear,” said McPherron. “Then last summer we found a larger, more complete tool that is unmistakably a lissoir like those we find in later, modern human sites or even in leather workshops today.”

This isn’t the first time Neanderthal bone tools have been found, but previous implements  looked like stone tools made with stone knapping percussive techniques.

A reconstruction of how lissoirs, made of deer ribs, could have been used to prepare hides to make them more supple, lustrous and impermeable. (© Abri Peyrony & Pech-de-l’Azé I Projects)

“Neanderthals sometimes made scrapers, notched tools and even hand axes from bone. They also used bone as hammers to resharpen their stone tools,” said McPherron. “But here we have an example of Neanderthals taking advantage of the pliability and flexibility of bone to shape it in new ways to do things stone could not do.”

The bone tools the researchers found were in sediments that contained  typical Neanderthal stone tools, along with the bones of hunted animals, including horses, reindeer, red deer and bison.

The research teams say they  found evidence only of Neanderthals at both dig sites, and no sign of modern humans that could have tainted and compromised their findings.

Hubble Helps Astronomers Solve 40 Year-Old Mystery

Posted August 9th, 2013 at 10:52 pm (UTC+0)
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Radio/visible light all-sky View of the Magellanic Stream  (NASA)

Radio/visible light all-sky View of the Magellanic Stream (NASA)

Astronomers finally have been able to solve a 40-year mystery thanks to the Hubble Space Telescope.

For over four decades astronomers have been trying to find the origin of the Magellanic Stream, a long ribbon of hydrogen gas clouds that stretch almost halfway around our own Milky Way galaxy.

The Magellanic Stream is connected to the Large and Small Magellanic Clouds, which are two small and irregular galaxies that are orbiting the Milky Way.

These irregular galaxies – those that do not have a distinctive regular shape – are among the Milky Way’s closest galactic neighbors and have long provided stargazers with spectacular astronomical images, even more so since advanced telescopes like the Hubble went online.

The Magellanic Stream was discovered with radio telescopes in the early 1970’s and since then astronomers have wanted to know whether the stream’s origination came from one or both of the clouds.

Close-up radio map of the Magellanic Stream  (Leiden-Argentine-Bonn (LAB) Survey)

Close-up radio map of the Magellanic Stream (Leiden-Argentine-Bonn (LAB) Survey)

Using recent Hubble observations, two teams of astronomers found that most of the stream’s gas pulled away from the Small Magellanic Cloud about 2 billion years ago. They also found that a second region of the stream was created a little more recently from the Large Magellanic Cloud.

The astronomers, led by Andrew J. Fox of the Space Telescope Science Institute in Maryland, were able to make their findings with the Hubble’s Cosmic Origins Spectrograph.

This device aboard the space telescope allowed them to determine the amount of heavy elements – anything heavier than helium – such as oxygen and sulfur at several areas alongside the Magellanic Stream. They were able to detect those heavy elements by observing the way they absorbed ultraviolet light.

The Hubble in orbit above the Earth (Photo: NASA)

The Hubble in orbit above the Earth (Photo: NASA)

One team said that they found a small amount of oxygen and sulfur along most of the stream, which matched the levels of the elements that was in the Small Magellanic Cloud when the stream first formed. The team was surprised to discover a much higher level of sulfur in an area of the stream that’s closer to the Magellanic Clouds.

“We’re finding a consistent amount of heavy elements in the stream until we get very close to the Magellanic Clouds and then the heavy element levels go up,” said Fox. “This inner region is very similar in composition to the Large Magellanic Cloud, suggesting it was ripped out of that galaxy more recently.”

Fox went on to explain that the only way his team was able to measure the quantities of the heavy elements in the stream was by using the ultraviolet observational method.  This is something he said could only be done with space telescopes like the Hubble, but not earth based telescopes since our atmosphere tends to absorb ultraviolet light.

The Large Cloud of Magellan (Credit & Copyright: Wei-Hao Wang (IfA, U. Hawaii))

The Large Cloud of Magellan (Credit & Copyright: Wei-Hao Wang (IfA, U. Hawaii))

Compared to other satellite galaxies of the Milky Way, the researchers pointed out that so far, both Magellanic Clouds have been able to hold on to their supplies of gas and are still able to create new stars because they’re more massive than others.

But that is something that they say probably won’t last forever since the Magellanic Clouds are getting closer to our own galaxy and are feeling, more and more, the gravitational effects of their much larger neighbor.

This growing gravitational pull is forcing each of the two clouds to smash into halos of gas that surround them, which in turn are pushing their own supplies of gas out. All of that along with a “gravitational tug-of-war” between the Magellanic Clouds themselves is leading to the production of a gas stream.

The researchers say that eventually the gassy stream being produced by the two satellite galaxies may pour onto the Milky Way’s stellar disk, which will fuel the creation of new stars. This mix of fresh gas is part of a process that produces star formation in a galaxy. Astronomers wanted to know the origin of that wayward gas so that they could better understand how galaxies make new stars.

The Small Cloud of Magellan (Credit & Copyright: Josch Hambsch, Robert Gendler)

The Small Cloud of Magellan (Credit & Copyright: Josch Hambsch, Robert Gendler)

“We want to understand how galaxies like the Milky Way strip the gas from small galaxies that fall into them and then use it to form new stars,” said Fox. “This seems like it’s an episodic process. It’s not a smooth process where a slow stream of gas comes in continuously. Instead, once in a while a large gas cloud falls in. We have a way of testing that here, where two galaxies are coming in. We’ve shown which of them is producing the gas that ultimately will fall into the Milky Way.”

The research and findings made by the astronomers in this investigation were outlined in two papers that were published in a recent issue of the “Astrophysical Journal.”  Fox was the lead author of one paper, while Philipp Richter of Germany’s University of Potsdam served as the lead author of the second paper.

Chocolate Could Be the Latest ‘Brain’ Food

Posted August 7th, 2013 at 8:00 pm (UTC+0)
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Enjoying a nice hot cup of cocoa (Orin Zebest via Creative Commons @ Flickr)

(Orin Zebest via Creative Commons @ Flickr)

Chocoholics have a new reason to enjoy their favorite treat free of guilt.  New research suggests chocolate is good for keeping your brain healthy and functioning sharply, perhaps delaying or slowing diseases such as Alzheimer’s.

A Harvard researcher found that drinking  two cups of hot chocolate a day helps older people keep their brains healthy and their thinking abilities strong.

“We’re learning more about blood flow in the brain and its effect on thinking skills,” said Farzaneh A. Sorond, of the Harvard Medical School and a Boston area neurologist. “As different areas of the brain need more energy to complete their tasks, they also need greater blood flow. This relationship, called neurovascular coupling, may play an important role in diseases such as Alzheimer’s.”

Sorond studied 60 people who were, on average, 73 years old, and didn’t have any form of dementia.

Over a 30-day period, Sorond had his volunteers drink two cups of hot cocoa a day while abstaining from consuming any other forms of chocolate during that time.

The study participants didn’t drink the same cocoa. Half  consumed hot cocoa  enhanced with an additional amount of the antioxidant flavanol, which is normally found in cocoa as well as tea and some fruits and vegetables.  The  other half received cocoa with a much smaller amount of the added antioxidant.

Sorond found that the amount of flavanol enhancement made no difference between the two groups of people, but drinking hot chocolate did seem to have an impact.

A delicious cup of hot chocolate (Paul Wilkinson via Wikimedia Commons at Flickr)

(Paul Wilkinson via Wikimedia Commons at Flickr)

Throughout the 30-day period, the study participants took memory and thinking skills tests as well as ultrasound tests to measure the amount of blood flow to the brain.

Eighteen participants showed signs of having impaired blood flow to their brains at the start of the study. By the end of the 30-day test period, those 18 people showed an 8.3-percent improvement in the blood flow to the working areas of their brain. They also improved their performance on a  working memory test, with scores dropping from 167 seconds at the beginning of the study to 116 seconds at the end.

However, study participants who started the tests with normal brain blood flow showed no improvement.

Twenty-four of the research participants – a mix of those with and without the restricted brain blood flow – were given MRI scans of their brains to see if there were any tiny areas of brain damage.

The MRI scans revealed that those with reduced blood flow were also more likely to have these small areas of brain damage.

“More work is needed to prove a link between cocoa, blood flow problems and cognitive decline,” said Paul B. Rosenberg of Johns Hopkins School of Medicine in Baltimore, who wrote an editorial that accompanied the study. “But this is an important first step that could guide future studies.”

Warmer Climate Linked to Increased Human Violence

Posted August 2nd, 2013 at 7:45 pm (UTC+0)
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As global temperatures rise, so do our levels of hostility and violence, according to a new study.

Scientists from the University of California, Berkeley and Princeton University  discovered a strong link between shifts in climate to human violence around the world.  The study found that even minor climate deviations, such as slight changes in normal temperature and rainfall, can greatly increase the risk of conflict.

The link between climate variations and violent behavior was noted on a small scale—in one-on-one crimes like assault, murder or domestic abuse—as well as on a much grander scale involving riots or civil war.

Unlike previous similar studies, this project combined data and evidence from a wider number of fields such as economics, political science, geography, psychology and archeology, according to Professor Edward Miguel from the University of California Berkeley.

Climate shifts researchers explored included temperature as well as rainfall—from very low rainfall and drought conditions to extreme amounts of rainfall.

El Castillo, also known as the Temple of Kukulkan - This is a Mesoamerican step-pyramid built by the pre-Columbian Maya civilization sometime between the 9th and 12th centuries in what is now the Mexican state of Yucatá (Daniel Schwen via Wikimedia Commons)

This is a Mesoamerican step-pyramid built by the pre-Columbian Maya civilization sometime between the 9th and 12th centuries in what is now the Mexican state of Yucatá (Daniel Schwen via Wikimedia Commons)

The scientists say  their findings could have critical implications for understanding the impact of future climate change on human societies. Many global climate models project temperature increases of at least 2 degrees Celsius over the next half century.

The researchers compared extensive data,  spanning from ancient times until today.  Collecting more material than any prior study, the researchers were able to show that the Earth’s climate plays a more influential role in human affairs than previously thought.

Among the historical correlations researchers found was the case of the advanced Mayan civilization which was established around 2000 BC in what is now Mexico and Central America.  Some scholars say this Mesoamerican civilization peaked between the years 250 to 900 AD, when it mysteriously collapsed.

Scientists and historians, including those involved in this study, theorize that climate may have had a lot to do with the Mayan decline and failure.

“The Mayan civilization, the Mayan empire…during the 9th century AD, experienced an unprecedented century of warm, dry weather,” said Miguel. “In fact, they had three mega-droughts during that century and at the end of the third mega-drought, that’s the time at which that civilization collapsed into civil war never to recover its previous grandeur.”

A photo from 2008 showing armed fighters including child soldiers from Al-shabab group in cars outside Mogadishu, Somalia. (AP /Farah Abdi Warsameh/File)

A photo from 2008 showing armed fighters including child soldiers from Al-shabab group in cars outside Mogadishu, Somalia. (AP)

Looking at the link between climate and violence in more modern times, Miguel pointed to hot temperatures and dry conditions in Somalia  and the extreme violence it has endured in recent times.

“When you have temperature spikes on top of what’s already a very hot place, that’s associated with political violence in Somalia, so Somalia is an African case where you can see this come through very clearly,” said Miguel.

The study also found a link between high temperatures and a rise in domestic violence in India.

In Brazil, scientists found a correlation between rainfall and land invasions. Miguel pointed to a landless people’s movement in the South American country that organizes violent raids.

“It turns out that when rainfall is really bad, either way too much or way too little rainfall in a given year, in those years you see spikes in the number of land invasions in Brazil,” said Miguel.

Results of the Berkeley/Princeton research could be used to predict future violent trends and potential trouble spots around the world, which could help in the development of strategies that would address possible violence and conflict in the future.

Drought's impact on a field of corn. (CraneStation/Creative Commons via Flickr)

Drought’s impact on a field of corn. (CraneStation/Creative Commons via Flickr)

“There are at least two different approaches you can take, given these findings,” Miguel said.

The first approach is building better forecasts for where there will be potential violence going forward.

“So if we know, for instance, that temperatures are rising very quickly in a part of the world that is prone to civil conflict, then early on in that year or maybe there’s a drought that year, that is a trouble spot where governments and foreign aid donors and other agencies should focus their efforts,” said Miguel.

The second approach Miguel suggested would be to use the results to really understand just how high the stakes are in dealing with climate change in the next 40 to 50 years.

“[We] could look at the changing climate and try to craft new policies to deal with changing climate,” said Miguel. “We can develop new technologies and approaches that are more resilient to a changing climate. That may be our only way out.”

Professor Edward Miguel joins us this weekend on the radio edition of “Science World.”  He’ll tell us  why a deviation in climate could play a role in determining human behavior.  So, either tune into the show (see right column for scheduled times) or check out the interview below.

>>>> Listen to the interview here

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