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Student satisfaction and student perceptions of quality at international branch campuses in the United Arab Emirates

Student satisfaction and student perceptions of quality at international branch campuses in the United Arab Emirates | Science Communication from mdashf | Scoop.it

Abstract

The international branch campus has emerged as a popular form of transnational higher education but to date little research has been undertaken on student perceptions and experiences, other than the student feedback evaluations conducted by institutions. This research employed a survey questionnaire to investigate student perceptions of study at international branch campuses in the United Arab Emirates (UAE), the country which hosts the largest number of branch campuses globally. Across the seven dimensions examined – programme effectiveness, quality of lecturers and teaching, student learning, assessment and feedback, learning resources, use of technology, and facilities/social life – it was found that students are largely satisfied. The findings refute many of the criticisms of international branch campuses in the literature, regarding quality, political or ideological issues.


Via Dr Vangelis Tsiligiris
mdashf's insight:

Higher Education around the world 

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The latest trends in physics. Speed of Light.

Much of this article is reviewed and updated today, the: (07 January 2014). It has become more interesting, less confusing and more clarifying. Its totally worth reading this article, I would say. ...
mdashf's insight:

A reviewed and edited article from mdashf that clarifies issues regarding speed of light and in what way the author saw the neutrino could have broken the speed barrier of Einstein's photons, which they could not nevertheless fo rother reasons. 

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A few thoughts on religion and science

A few thoughts on religion and science | Science Communication from mdashf | Scoop.it
Secularism is not an idea of looking at religions equally as we have often been told. All religions are different from each other and so are their Gods. The "Gods" reflect the mindset of their beli...
mdashf's insight:

Some casual thoughts on science and religion from a  write-up of 2009, January by me.  

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Teacher's Corner. Whats your real salary Vs what you are getting (Indian High Schools only)

Teacher's Corner. Whats your real salary Vs what you are getting (Indian High Schools only) | Science Communication from mdashf | Scoop.it
Primary School Teachers who are getting the scale of 4500-125-7000 presently have been upgraded to 6500-200-10500 and finally fixed in Pay Band-2 at 9300-34800 with Grade Pay of 4200.

Bol mere a...
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characteristics of photon

characteristics of photon | Science Communication from mdashf | Scoop.it
SO mass-energy equivalence is a special theory of realtivity effect and gravitational tensor-coupling has got nothing to do with it. A photon gets it's energy-momentum (( energy/momentum)) from QED...
mdashf's insight:

When it comes to mass and energy, particles with and without mass then exactly what you should be careful about. The Uncertainty relations will produce additional "not so talked about relations of uncertainty" !! A very fundamental, known but not all sides known aspect of Physics which I have discovered after many different problems were related and caused me to think about the problem for more than half a year and gradually shed qualitative as well as quantitative light into the matter, plus the mathematical form helped me "solve" the OPERA anomaly from fundamental Physics POV. This article answers some of these " care to be taken " in Photon-matters at a good detail. {1. will be well read only if conncted with some more articles which are nonetheless to be found on the same website but not the same sequence 2. Only one line needs to be corrected: perhaps the talking about rest-mass or rest-frame of photon, this I have corrected and devoted one full article recently within last 1 week, but you are encouraged to find that article then matters will be far more clear, plus I am thinking to write a few more articles in this context pretty soon}

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What's Your Writing Fee? - ProfHacker - The Chronicle of Higher Education

What's Your Writing Fee? - ProfHacker - The Chronicle of Higher Education | Science Communication from mdashf | Scoop.it
mdashf's insight:

100 $ per piece is not on the lower bottom of a compensation although if someone pays you 500 $ per piece that would be awesome, and its only you who has proved what to earn. If one devotes full time writing and gets 5 articles a day written one can in 20 working days a month gets 10000 $ which is an excellent compensation for any one writing and earning simply from writing. I do not disagree how many hours go into writing and how difficult certain research can become. I simply think of how sustainably one can write. The more one is writing the more one owuld be at wit's end. 

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Could Einstein have thought Equivalence from simple notions of Geometry ? Yes.

Could Einstein have thought Equivalence from simple notions of Geometry ? Yes. | Science Communication from mdashf | Scoop.it
Now it may also be related that light bends in a denser media compared to a rarer media because an additional rotational force is working. In other words the definition of straight line has to chan...
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Writing a motivational letter for PhD ..

Writing a motivational letter for PhD .. | Science Communication from mdashf | Scoop.it
6. Why do you want to work for our organization? Where do you see yourself in 8-10 years from now?


Mention the strong point of your varsity's choice: eg if Nethrlands CooCoo University is ...
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Leaf Growth & Tree Height Limited By Physics

Leaf Growth & Tree Height Limited By Physics | Science Communication from mdashf | Scoop.it

New research indicates that leaf growth may not be as complicated as it seems. When compared species to species, shorter trees exhibit a greater variety of leaf sizes than taller ones, with the tallest trees all having leaves that measure 10 to 20 centimeters in length.

 

The scientists published their findings in the journal Physical Review Letters⊃1;. The narrow size range may be simply explained in the inner workings of trees. If this is correct, this could also explain why the tallest trees can only attain about 100 meters.

 

The team only considered angiosperms like maples and oaks, not gymnosperms, like pines and redwoods. They reviewed data for 1925 species and found that among angiosperms shorter than 30 meters, leaf length varies enormously, from 3 cm all the way up to 60 cm. The range narrows as the trees become taller.

 

The flow of sap and energy throughout the tree is what explains this. A leaf of an angiosperm produces a sugary sap that flows into a network of cells called the phloem, which transports the sap down to the tree’s trunk and through the roots. While it’s in transit, the tree metabolizes the sugar. The flow is driven by the difference in concentration in the sugars, which generates osmotic pressure.

 

The scientists modeled a tree as a pair of cylindrical tubes. A short, permeable tube, which represented the phloem in the leaf, was attached to a long, impermeable tube, the phloem in the trunk. Sap diffuses into the leave phloem and travels down into the trunk phloem. The longer the permeable leaf tube is, the more the surface area it has, so the more easily sap can enter. In the trunk phloem, the longer the tube is, the more resistance it offers to flow.

 

The scientists then considered how the total flow of sap and energy varies with leaf length. If the leaves are big, the resistance from the trunk limits the flow and making the leaves bigger than a certain maximum length yields no additional flow or benefit. On the other hand, if the leaves are very small, their resistance limits the flow. And if the leaf is shorter than a certain minimum length, the sap would flow through the phloem more slowly than it could diffuse through the entire tree.

 

Trees taller than 100 meters simply could not produce leaves that obey both length limits, setting a limit for tree height. Other scientists think that the uniformity of leaf size amongst the tallest trees could come from the comparable environments and conditions that produce them.

 

One way to test how the flow speed varies with the height of a tree and the length of its leaves would be to directly measure it in different species of tall trees, but that might require taking an MRI machine into a rain forest canopy.


Via Dr. Stefan Gruenwald
mdashf's insight:

why some trees are so tall while others are short? well their leaves size will be affected as well deoending on their heights. Its like very tall men will have proportionate to their height smaller fingers. But shorter men and women will grow fingers in many differet ratio to their height. You lose certain privilege if you are tall. 

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why scientists think photon is massless ?

why scientists think photon is massless ? | Science Communication from mdashf | Scoop.it
GHz makes the time window really small. For such a senstive time measurement one must make a correspondingly larger error on energy therefore mass. That is uncertainty principle of energy-time. SO ...
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Experimental and theoretical reason why photons, the carriers that bring us light, are ones without any mass.

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How to tell who a person is thinking about?

How to tell who a person is thinking about? | Science Communication from mdashf | Scoop.it

It is possible to tell who a person is thinking about by analyzing images of his or her brain. Our mental models of people produce unique patterns of brain activation, which can be detected using advanced imaging techniques according to a study by Cornell University neuroscientist Nathan Spreng and his colleagues.

 

"When we looked at our data, we were shocked that we could successfully decode who our participants were thinking about based on their brain activity," said Spreng, assistant professor of human development in Cornell's College of Human Ecology.

 

Understanding and predicting the behavior of others is a key to successfully navigating the social world, yet little is known about how the brain actually models the enduring personality traits that may drive others' behavior, the authors say. Such ability allows us to anticipate how someone will act in a situation that may not have happened before.

 

To learn more, the researchers asked 19 young adults to learn about the personalities of four people who differed on key personality traits. Participants were given different scenarios (i.e. sitting on a bus when an elderly person gets on and there are no seats) and asked to imagine how a specified person would respond. During the task, their brains were scanned using functional magnetic resonance imaging (fMRI), which measures brain activity by detecting changes in blood flow.

 

They found that different patterns of brain activity in the medial prefrontal cortex (mPFC) were associated with each of the four different personalities. In other words, which person was being imagined could be accurately identified based solely on the brain activation pattern.

 

The results suggest that the brain codes the personality traits of others in distinct brain regions and this information is integrated in the medial prefrontal cortex (mPFC) to produce an overall personality model used to plan social interactions, the authors say.

 

"Prior research has implicated the anterior mPFC in social cognition disorders such as autism and our results suggest people with such disorders may have an inability to build accurate personality models," said Spreng. "If further research bears this out, we may ultimately be able to identify specific brain activation biomarkers not only for diagnosing such diseases, but for monitoring the effects of interventions."


Via Dr. Stefan Gruenwald
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Oldest Meteorite Impact Crater on Earth Discovered

Oldest Meteorite Impact Crater on Earth Discovered | Science Communication from mdashf | Scoop.it

The world's oldest meteorite crater —a giant impact zone more than 62 miles wide — has been found in Greenland, scientists say.

 

Scientists think it was formed 3 billion years ago by a meteorite 19 miles (30 kilometer) wide — which, if it hit Earth today, would wipe out all higher life. The crater is so wide that it would reach the edge of space 62 miles (100 km) above Earth if stood on end.

 

The crater was "discovered" at an office in Copenhagen by scientist Adam Garde as he pored over maps showing nickel and platinum abundance in the target region of West Greenland. Garde, a senior research scientist with the Geological Survey of Denmark and Greenland, saw a both simple and extreme explanation for several strange geological features in this region: an impact from a meteorite that may have contained valuable metals.


Via Dr. Stefan Gruenwald
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Georgia Tech Researchers Show That Graphene Antennas Would Enable Terabit Wireless Downloads

Georgia Tech Researchers Show That Graphene Antennas Would Enable Terabit Wireless Downloads | Science Communication from mdashf | Scoop.it

Want to wirelessly upload hundreds of movies to a mobile device in a few seconds? Researchers at Georgia Tech have drawn up blueprints for a wireless antenna made from atom-thin sheets of carbon, or graphene, that could allow terabit-per-second transfer speeds at short ranges.

 

“It’s a gigantic volume of bandwidth. Nowadays, if you try to copy everything from one computer to another wirelessly, it takes hours. If you have this, you can do everything in one second—boom,” says Ian Akyildiz, director of the broadband wireless networking laboratory at Georgia Tech.

 

A terabit per second could be done at a range of about one meter using a graphene antenna, which would make it possible to obtain 10 high-definition movies by waving your phone past another device for one second. Akyildiz and colleagues have also calculated that at even shorter ranges, such as a few centimeters, data rates of up to 100 terabits per second are theoretically possible.

 

Graphene is a sheet of carbon just one atom thick, in a honeycomb structure, and it has many desirable electronic properties. Electrons move through graphene with virtually no resistance—50 to 500 times faster than they do in silicon. To make an antenna, the group says, graphene could be shaped into narrow strips of between 10 and 100 nanometers wide and one micrometer long, allowing it to transmit and receive at the terahertz frequency, which roughly corresponds to those size scales. Electromagnetic waves in the terahertz frequency would then interact with plasmonic waves—oscillations of electrons at the surface of the graphene strip—to send and receive information.  

 

“This points out and provides a set of classical calculations on estimates of sizes and performance: it points out that there is something worthwhile here,” says Phaedon Avouris, an IBM fellow who leads graphene and other nanometer-scale technology at IBM Research in Yorktown Heights, New York. “It doesn’t solve the whole problem, but points out an opportunity.”

 

As well as facilitating high-speed communication between devices, graphene antennas could enable faster wireless connections between nanoscale components on chips. “Antennas made of graphene can be made much smaller in all dimensions than a metal wire antenna. It can be made to be on the order of a micrometer or a few nanometers,” Avouris says. “The significance is that the antenna can be incorporated in a very small object.”

Of course, myriad challenges lie ahead. Antennas don’t work alone; they rely on many other components—such as signal generators and detectors, amplifiers, and filters—all of which would have to be fabricated at similar scales and with similar speeds in order to make a complete device. 

Researchers also need to work out how to do the manufacturing. Working with the material is extremely tricky, because its properties change when it comes in contact with other materials. 

 

However, the Georgia Tech group hopes to make a prototype of an antenna within a year, Akyildiz added, and other components after that.  

 


Via Dr. Stefan Gruenwald
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Ancient Vanity - Human Ancestors 75,000 Years Were Fashion Conscious

Ancient Vanity - Human Ancestors 75,000 Years Were Fashion Conscious | Science Communication from mdashf | Scoop.it

The 2013 Academy Awards were, as always, as much about making appearances as about making films, as red carpet watchers noted fashion trends and faux pas. Both Jessica Chastain and Naomi Watts wore Armani, although fortunately not the same dress. And Best Supporting Actress Anne Hathaway switched from Valentino to a controversial pale pink Prada at the last minute because her original dress looked too much like someone else's. Of course, no actress would be caught dead wearing the same style 2 years in a row. A new study of ancient beaded jewelry from a South African cave finds that ancient humans were no different, avoiding outdated styles as early as 75,000 years ago.

 

Personal ornaments, often in the form of beads worn as necklaces or bracelets, are considered by archaeologists as a key sign of sophisticated symbolic behavior, communicating either membership in a group or individual identity. Such ornaments are ubiquitous in so-called Upper Paleolithic sites in Europe beginning about 40,000 years ago, where they were made from many different materials—animal and human teeth, bone and ivory, stone, and mollusk shells—and often varied widely among regions and sites.

 

Even more ancient personal ornaments go back to at least 100,000 years ago in Africa and the Near East. But this earlier jewelry seems less variable and was nearly always made from mollusk shells. So some archaeologists have questioned whether these earlier ornaments played the same symbolic roles as the later ones, or even whether they were made by humans at all.

 

In a new study in press at the Journal of Human Evolution, a team led by archaeologist Marian Vanhaeren of the University of Bordeaux in France claims to have found evidence of a relatively sudden shift in the way that shell beads were strung. The beads were found at Blombos Cave in South Africa in archaeological layers dated between 75,000 and 72,000 years ago, during a time period marked by four distinct layers of artifacts called the Still Bay tradition. This tradition includes bone awls and sophisticated stone spear points and knives, as well as beads from jewelry: sixty-eight specimens of the southern African tick shell, Nassarius kraussianus, most found clustered together and thought to be part of individual necklaces or bracelets. All the shells are perforated with a single hole, and the team's microscopic studies—as well as experiments with shells of the same species collected near the site—have suggested that they were punctured with a finely tipped bone point.


Via Dr. Stefan Gruenwald
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QuickWire: An Unhappy Lawrence Lessig Takes on Apple - Wired Campus - The Chronicle of Higher Education

QuickWire: An Unhappy Lawrence Lessig Takes on Apple - Wired Campus - The Chronicle of Higher Education | Science Communication from mdashf | Scoop.it
mdashf's insight:

customer dissatisfaction with Apple Upgrades !!

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Milkyway supernova to be visible from Earth within 50 years - Indian Express

Milkyway supernova to be visible from Earth within 50 years - Indian Express | Science Communication from mdashf | Scoop.it
In some good news for space enthusiasts, a Milky Way supernova could be visible from Earth sometime in the next 50 years.
mdashf's insight:

1. Supernovae will be visible from earth (naked eye has lower chance but infrared telescope 100 % chance) 

 

2. Within next 50 years time. and this supernovae is from our own galaxy Milky-way.

 

3. A supernovae is the phenomena of a star exploding violently into its constituents and throwing that debris into its surrounding in terms of matter and radiation that glows in visible, infrared and other forms of radiation. Matter includes neutrinos, the tiny little constituents of Universe that are almost mass-less and charge-less like the photons and far more mysterious. The stars are nuclear fire-houses. When all the nuclear  fuel is exhausted the star has no more and its shells are thrown off much like an exploding bomb. The inner core continues to collapse gravitationally forming so called black-holes if critical condition of the star-mass being 1.4 times higher than Sun's mass is satisfied. 

 

4. The scientists are hopeful to study the release of neutrino which is produced often days or hours before the other forms of radiation is produced hence this can shed more understanding into the phenomena.

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Stanford professor dies after year-long search for bone marrow donors fails - The Times of India

Stanford professor dies after year-long search for bone marrow donors fails - The Times of India | Science Communication from mdashf | Scoop.it
After a year-long, worldwide campaign by her students, friends and family to find a bone marrow donor for her, Nalini Ambady, a Stanford professor of Indian origin, succumbed to leukaemia on Monday.
mdashf's insight:
She is also a Hero like Sunita Williams and Kalpana Chawla. She is the first from India to teach in the Stanford Psychology Department. She needed a bone marrow transplant. (When your blood is no more acting towards your safety and you need someone'else's blood to be transplanted to your body, a form of a dreaded cancer) 50% of her match (people whose blood marrow type matches yours so you have a possible donor just in time to save your life) backed out. She dies because no one is educated enough to see that there is no harm in donating some of your blood to a patient who is in serious need of such) Unfortunately parental disagreement (a superfluous reason that acts against your marriage, your career move, your life choices and what not ) Our heroes die because we do not recognize them in time. (Remember Ramanujan anyone? ) Then we cry with profanity when its all gone. This reminds me something. Back in 2006-7 perhaps I had signed a camp at Tech which wanted to see if I can be a possible donor in future for some one who is in need of blood transplant (bone marrow). I happily signed as a donor. (I was also a donor-yes in my Driving license for organs that I might no more need since I am about to die or I have already dies but not my organs) 2 years ago, 5 years or so after I had signed that as a prospectus donor, I got an email and a phone call from California. These are the people that had hosted the camp at Tech in Blacks-burg. (for joke sake yes the lady who was signing us off was a good looking Korean woman) The phone call survived a good half an hour or so detailing me what needs to be done if my donation is to materialize. I needed to be traveling to Delhi to get all checks done and if everything is fine I would be donating. I was thinking I could be useful for someones life. (I also tried my lackluster dying out American accent after many years of leaving the US) Then there was some paperwork (I hate paper-work not blood donation, I have donated blood more than 10 years ago, I think 1 or 2 big pouches, here in my home town) .. I got a couple of more communiques reg. this but for some reason I didn't have to donate (If I remember my blood wasn't perhaps necessary anymore given some better match might have been found) Until today when I read this news when I remembered this. If you have a chance of doing something good do it. If you have a chance doing something bad, don't do it.
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2013 AAUP Faculty Salary Survey: Sortable Table

2013 AAUP Faculty Salary Survey: Sortable Table | Science Communication from mdashf | Scoop.it
Annual pay averages $84,000; the increase just matches inflation. Not all of the numbers are heartening, though.
mdashf's insight:

Columbia University pays its Professors the most (more than 200 K per anum) and its the only university in the top 60 which pays its instructors a great deal of respect, even more than Assistant Professors in terms of salary an instructor draws more than Assistant Professor's and only at Columbia University. No other University including Chicago, Harvard, Cal-Tech. Princeton have this privilege towards their instructors, they pay about 50-75% what they pay to their Asst Professors. caltech; instructor Asst Professor disparity is even more than 50% !!

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Optical Path

Optical Path | Science Communication from mdashf | Scoop.it
In the last few weeks I am trying to understand why light traverses straight lines and why it refracts. The other day I saw a little mug floating inside a bucket full of water. Inside water any obj...
mdashf's insight:

Well written although slightly technical !!

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Why Sun is circular but star twinkles?

Why Sun is circular but star twinkles? | Science Communication from mdashf | Scoop.it
The frequency of light is small because the energy or intensity is low. So you see twinkles. But light is still moving at the same speed towards us. It takes 4.5 years from some stars while taking ...
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CERN Physicists Attempt to Measure Gravitational Mass of Antihydrogen

CERN Physicists Attempt to Measure Gravitational Mass of Antihydrogen | Science Communication from mdashf | Scoop.it

A team of researchers working with CERN’s Antihydrogen Laser Physics Apparatus (ALPHA) has reported the first direct measurement of gravity’s effect on antimatter, specifically antihydrogen in free fall.

 

“The atoms that make up ordinary matter fall down, so do antimatter atoms fall up? Do they experience gravity the same way as ordinary atoms, or is there such a thing as antigravity?”

 

“These questions have long intrigued physicists,” said Dr Joel Fajans of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, co-author of apaper reporting the results in Nature Communications.

 

“Because in the unlikely event that antimatter falls upwards, we’d have to fundamentally revise our view of physics and rethink how the Universe works.”

 

So far, all the evidence that gravity is the same for matter and antimatter is indirect, so the team decided to use their ongoing antihydrogen research to tackle the question directly.

 

The ALPHA experiment captures antiprotons and combines them with antielectons (positrons) to make antihydrogen atoms, which are stored and studied for a few seconds in a magnetic trap. Afterward, however, the trap is turned off and the atoms fall out. The researchers realized that by analyzing how antihydrogen fell out of the trap, they could determine if gravity pulled on antihydrogen differently than on hydrogen – the anomaly would be noticeable in ALPHA’s existing data on 434 anti-atoms.


Via Dr. Stefan Gruenwald
mdashf's insight:

Do antiparticles get duped by gravity or they get equal shares in a swing of gravity. Do they get an opposite swing? 

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Climate change, not human activity, led to megafauna extinction

Climate change, not human activity, led to megafauna extinction | Science Communication from mdashf | Scoop.it
Most species of gigantic animals that once roamed Australia had disappeared by the time people arrived, a major review of the available evidence has concluded.

 

The research challenges the claim that humans were primarily responsible for the demise of the megafauna in a proposed "extinction window" between 40,000 and 50,000 years ago, and points the finger instead at climate change.

 

An international team led by the University of New South Wales, and including researchers at the University of Queensland, the University of New England, and the University of Washington, carried out the study. It is published in the Proceedings of the National Academy of Sciences.

 

"The interpretation that humans drove the extinction rests on assumptions that increasingly have been shown to be incorrect. Humans may have played some role in the loss of those species that were still surviving when people arrived about 45,000 to 50,000 years ago -- but this also needs to be demonstrated," said Associate Professor Stephen Wroe, from UNSW, the lead author of the study.

 

"There has never been any direct evidence of humans preying on extinct megafauna in Sahul, or even of a tool-kit that was appropriate for big-game hunting," he said.

 

About 90 giant animal species once inhabited the continent of Sahul, which included mainland Australia, New Guinea and Tasmania.

 

"These leviathans included the largest marsupial that ever lived -- the rhinoceros-sized Diprotodon - and short-faced kangaroos so big we can't even be sure they could hop. Preying on them were goannas the size of large saltwater crocodiles with toxic saliva and bizarre but deadly marsupial lions with flick-blades on their thumbs and bolt cutters for teeth," said Associate Professor Wroe.

 

The review concludes there is only firm evidence for about 8 to 14 megafauna species still existing when Aboriginal people arrived. About 50 species, for example, are absent from the fossil record of the past 130,000 years.


Via Dr. Stefan Gruenwald
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Marco Bertolini's curator insight, May 7, 2013 3:21 AM

Des scientifiques sont à présent certains qu'un changement climatique a détruit la mégafaune d'Australie.  Et non pas l'action humaine, comme on l'a longtemps cru.  Un avertissement ?

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Peptide bond formation in deep space: Evidence that comets could have seeded life on Earth

Peptide bond formation in deep space: Evidence that comets could have seeded life on Earth | Science Communication from mdashf | Scoop.it

A new experiment simulating conditions in deep space reveals that the complex building blocks of life could have been created on icy interplanetary dust and then carried to Earth, jump-starting life.

 

Chemists from the University of California, Berkeley, and the University of Hawaii, Manoa, showed that conditions in space are capable of creating complex dipeptides – linked pairs of amino acids – that are essential building blocks shared by all living things. The discovery opens the door to the possibility that these molecules were brought to Earth aboard a comet or possibly meteorites, catalyzing the formation of proteins (polypeptides), enzymes and even more complex molecules, such as sugars, that are necessary for life.

 

“It is fascinating to consider that the most basic biochemical building blocks that led to life on Earth may well have had an extraterrestrial origin,” said UC Berkeley chemist Richard Mathies, coauthor of a paper published online last week and scheduled for the March 10, 2013 print issue of The Astrophysical Journal.

 

While scientists have discovered basic organic molecules, such as amino acids, in numerous meteorites that have fallen to Earth, they have been unable to find the more complex molecular structures that are prerequisites for our planet’s biology. As a result, scientists have always assumed that the really complicated chemistry of life must have originated in Earth’s early oceans.

 

In an ultra-high vacuum chamber chilled to 10 degrees above absolute zero (10 Kelvin), Seol Kim and Ralf Kaiser of the Hawaiian team simulated an icy snowball in space including carbon dioxide, ammonia and various hydrocarbons such as methane, ethane and propane. When zapped with high-energy electrons to simulate the cosmic rays in space, the chemicals reacted to form complex, organic compounds, specifically dipeptides, essential to life.

 

At UC Berkeley, Mathies and Amanda Stockton then analyzed the organic residues through the Mars Organic Analyzer, an instrument that Mathies designed for ultrasensitive detection and identification of small organic molecules in the solar system. The analysis revealed the presence of complex molecules – nine different amino acids and at least two dipeptides – capable of catalyzing biological evolution on earth.


Via Dr. Stefan Gruenwald
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Stomach cancer spotted by breath test is at least 90% accurate

Stomach cancer spotted by breath test is at least 90% accurate | Science Communication from mdashf | Scoop.it
Trials of a novel breath test for stomach cancer prove promising, say experts.

 

A quick and simple breath test can diagnose stomach cancer, study findings reveal. Scientists from Israel and China found the test was 90% accurate at detecting and distinguishing cancers from other stomach complaints in 130 patients. 

 

The British Journal of Cancer says the test could revolutionise and speed up the way this cancer is diagnosed. About 7,000 UK people develop stomach cancer each year and most have an advanced stage of the disease. Two-fifths of patients survive for at least a year, but only a fifth are still alive after five years, despite treatment. 

 

Currently doctors diagnose stomach cancer by taking a biopsy of the stomach lining using a probe and a flexible camera passed via mouth and down the gullet. The new test looks for chemical profiles in exhaled breath that are unique to patients with stomach cancer.

 

Cancer appears to give off a signature smell of volatile organic compounds that can be detected using the right technical medical kit - and perhaps even dogs. The science behind the test itself is not new - many researchers have been working on the possibility of breath tests for a number of cancers, including lung. But the work by Prof Hossam Haick, of the Technion-Israel Institute of Technology, suggests it is a good way to spot stomach cancer.

In the study, 37 of the patients had stomach cancer, 32 had stomach ulcers and 61 had other stomach complaints.

 

As well as accurately distinguishing between these conditions 90% of the time, the breath test could tell the difference between early and late-stage stomach cancers. The team are now running a bigger study in more patients to validate their test. Kate Law, director of clinical research at Cancer Research UK, said: "The results of this latest study are promising - although large scale trials will now be needed to confirm these findings. "Only one in five people are able to have surgery as part of their treatment as most stomach cancers are diagnosed at stages that are too advanced for surgery. Any test that could help diagnose stomach cancers earlier would make a difference to patients' long-term survival."


Via Dr. Stefan Gruenwald
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NASA: Europa's Ocean Right at the Surface May Closely Resemble Earth's

NASA: Europa's Ocean Right at the Surface May Closely Resemble Earth's | Science Communication from mdashf | Scoop.it
A study partially funded by NASA finds evidence of ocean salt on Europa's surface.

 

If you could lick the surface of Jupiter's icy moon Europa, you would actually be sampling a bit of the ocean beneath. A new paper by Mike Brown, an astronomer at the California Institute of Technology in Pasadena, Calif., and Kevin Hand from NASA's Jet Propulsion Laboratory, also in Pasadena, details the strongest evidence yet that salty water from the vast liquid ocean beneath Europa's frozen exterior actually makes its way to the surface.

 

The finding, based on some of the best data of its kind since NASA's Galileo mission (1989 to 2003) to study Jupiter and its moons, suggests there is a chemical exchange between the ocean and surface, making the ocean a richer chemical environment. The work is described in a paper that has been accepted for publication in the Astronomical Journal.

 

The exchange between the ocean and the surface, Brown said, "means that energy might be going into the ocean, which is important in terms of the possibilities for life there. It also means that if you'd like to know what's in the ocean, you can just go to the surface and scrape some off."

 

Europa's ocean is thought to cover the moon's whole globe and is about 60 miles (100 kilometers) thick under a thin ice shell. Since the days of NASA's Voyager and Galileo missions, scientists have debated the composition of Europa's surface. The infrared spectrometer aboard Galileo was not capable of providing the detail needed to identify definitively some of the materials present on the surface. Now, using the Keck II Telescope on Mauna Kea, Hawaii, and its OSIRIS spectrometer, Brown and Hand have identified a spectroscopic feature on Europa's surface that indicates the presence of a magnesium sulfate salt, a mineral called epsomite, that could have formed by oxidation of a mineral likely originating from the ocean below.

 

Brown and Hand started by mapping the distribution of pure water ice versus anything else. The spectra showed that even Europa's leading hemisphere contains significant amounts of non-water ice. Then, at low latitudes on the trailing hemisphere—the area with the greatest concentration of the non-water ice material—they found a tiny, never-before-detected dip in the spectrum.

The two researchers tested everything from sodium chloride to Drano in Hand's lab at JPL, where he tries to simulate the environments found on various icy worlds. At the end of the day, the signature of magnesium sulfate persisted.

 

The magnesium sulfate appears to be generated by the irradiation of sulfur ejected from the Jovian moon Io and, the authors deduce, magnesium chloride salt originating from Europa's ocean. Chlorides such as sodium and potassium chlorides, which are expected to be on the Europa surface, are in general not detectable because they have no clear infrared spectral features. But magnesium sulfate is detectable. The authors believe the composition of Europa's ocean may closely resemble the salty ocean of Earth.

 

Europa is considered a premier target in the search for life beyond Earth, Hand said. A NASA-funded study team led by JPL and the Johns Hopkins University Applied Physics Laboratory, Laurel, Md., has been working with the scientific community to identify options to explore Europa further. "If we've learned anything about life on Earth, it's that where there's liquid water, there's generally life," Hand said. "And of course our ocean is a nice, salty ocean. Perhaps Europa's salty ocean is also a wonderful place for life."


Via Dr. Stefan Gruenwald
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Richard Feynman on the Universal Responsibility of Scientists

Richard Feynman on the Universal Responsibility of Scientists | Science Communication from mdashf | Scoop.it

On harvesting the fruit of freedom of thought."Writers do not merely reflect and interpret life, they inform and shape life," E. B. Whit


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