Coursera makes top college courses free online

Coursera makes top college courses free online

  8:53:00 AM    Science Lover

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Daphne Koller and Andrew Ng share a vision in which anyone, no matter how destitute, can expand their minds and prospects with lessons from the world's top universities.

Coursera co-founders Andrew Ng and Daphne Koller

That dream was joined this week by a dozen vaunted academic institutions including Duke University, the Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland and the University of Edinburgh in Scotland.

The schools will add online versions of classes to Coursera.org, a website launched by Stanford University professors Koller and Ng early this year with debut offerings from Princeton, Stanford and two other US universities.

"We have a vision where students everywhere around the world, regardless of country, family circumstances or financial circle have access to top quality education whether to expand their minds or learn valuable skills," Koller said.

"Where education becomes a right, not a privilege."

Academic institutions are increasingly turning to the Internet as an educational platform. A Khan Academy website created by Massachusetts Institute of Technology (MIT) graduate Salman Khan provides thousands of video lectures.

The nonprofit behind prestigious TED gatherings recently launched a TED-Ed channel at YouTube that teams accomplished teachers with talented animators to make videos that captivate while they educate.

In May, Harvard University and MIT announced that they were teaming up to expand their online education programs -- and invited other institutions to jump on board.

Called edX, the $60 million joint venture builds on MIT's existing MITx platform that enables video lesson segments, embedded quizzes, immediate feedback, online laboratories and student-paced learning.

"Universities have come to realize that online is not a fad," Koller said. "The question is not whether to engage in this area but how to do it."

Coursera classes are free, and completion certificates are issued that people can use to win jobs or improve careers.

"If a student takes a Stanford computer class and a Princeton business class, it shows they are motivated and have skills," Koller said. "We know it has helped employees get better jobs."

Coursera is distinguishing itself with essentially virtual versions of real classes.

"A lot of what is out there is basically video with, perhaps, some static content like lecture notes," Koller said.

"We are providing an actual course exchange were people register and there is weekly homework that is graded with feedback about how they are doing."

Coursera classes launched in February with most of the courses slated to begin in the coming months but it has already attracted students in 190 countries, according to Koller.

Coursera uses crowd-sourcing to translate material into various languages and hopes to connect with French-speaking populations around the world with EPFL classes.

Hoping to spread knowledge around the world, Coursera is a way to inspire faculty to try new methods of teaching and find ways that Internet Age tools can enhance on-campus courses, according to Duke provost Peter Lange.

"Our faculty is incredibly excited by the idea of trying it out and seeing if we can learn from it," Lange said.

"I love the idealism of it; the potential to reach people who might never get the chance to attend the university."

Duke designs its online courses to get students involved, complete with social networking tools for collaborating outside of classes.

"This is a great experiment in innovation and learning," Lange said.

As of Friday, Coursera boasted about 740,000 students and that number is expected to soar as word spreads and class offerings expand.

Coursera plans to keep classes free but perhaps one day make money for operations by charging for course completion certificates or matching employers with qualified workers.

"Current ethos in Silicon Valley is that if you build a website that people keep coming back to and is changing the lives of millions, you can eventually make money," Koller said.

"If and when we develop revenue, universities will share in it."

Paying the bills is not a worry at Coursera due to generous backing that includes a $3.7 million combined investment by the University of Pennsylvania and the California Institute of Technology, as well as funding from venture capital powerhouse Kleiner Perkins Caufield & Byers.

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'Minority Report' software hits the real world

'Minority Report' software hits the real world

  8:00:00 AM    Science Lover

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The software behind the film "Minority Report" -- where Tom Cruise speeds through video on a large screen using only hand gestures -- is making its way into the real world.

The interface developed by scientist John Underkoffler has been commercialized by the Los Angeles firm Oblong Industries as a way to sift through massive amounts of video and other data.

And yes, the software can be used by law enforcement and intelligence services. But no, it is not the "pre-crime" detection program illustrated in the 2002 Steven Spielberg sci-fi film.

Kwin Kramer, chief executive of Oblong, said the software can help in searching through "big data" for information. It can also create souped-up video-conference capabilities where participants share data from multiple devices like smartphones and tablets, integrated into a large video display.

"We think the future of computing is multiuser, multiscreen, multidevice," Kramer told AFP.

"This system helps with big workflow problems."

A key part of the system is the gesture interface, which the company calls the "g-speak" spatial operating environment.

That grew out of a project by Underkoffler -- then a scientist at the prestigious Massachusetts Institute of Technology -- for "Minority Report," before he became chief scientist at startup Oblong.

"We have demo versions of this kind of software which show exactly the 'Minority Report' user experience, allowing you to move back and forth in time, or to zoom in to look at details," Kramer said.

He said the same software can help businesses to "allow better collaboration, visualization and analysis of large amounts of data.

"You can have a lot of data but it's hard to make use of that," Kramer said.

"It can be on different machines and hard to access. This allows multiple people to look at that."

An employee demonstrates the use of a data glove to navigate a map on a computer screen at Los Angeles-based software company Oblong Industries' offices in Washington in June 2012. The software behind the film "Minority Report" -- where Tom Cruise speeds through video on a large screen using only hand gestures -- is making its way into the real world.

Gestural interfaces have been developed for other firms including Microsoft's Kinect but Oblong says it has far more sophisticated systems which can use Kinect and more.

Some highly sensitive systems use a data glove which can be more precise than ordinary hand movements.

Oblong has contracts with firms such as Boeing, General Electric and Saudi Aramco to help in analyzing large amounts of data. It is also developing a gestural interface for onboard computers with automaker Audi.

It has raised an unspecified amount of venture capital from investors including Foundry Group, Energy Technology Ventures and Morgan Stanley Alternative Investment Partners.

Brad Feld, managing director at Foundry Group, said Oblong offers "a path to fundamentally change the way we interact with computers."

Yet the question Oblong often gets is how users can get the "Minority Report" software.

David Schwartz, the company's vice president for sales, said "We get calls from people in the military who say, 'I want the 'Minority Report' interface."

He said the systems could be used for a realistic version of high-tech software interfaces on TV shows like "CSI."

"They would like to get it for free," he added.

What makes the real-life version of the software different from the one seen on film is that Oblong does not supply the analytics of the futuristic "pre-crime" division.

That does not prevent a company or law enforcement agency from using the software and adding its own analytics.

"We think law enforcement and intelligence are big data users and we think our technology is the leader," Kramer said.

He said Oblong currently has no government customers in the United States or abroad but offers itself as "a core technology provider."

Still, Oblong leverages its role in the movies to get in the door, even if the software is not quite the same.

"I think most people look at those 'Minority Report' interfaces and imagine how they could use that flexible system in their own office or designs studio," Kramer said.

"It isn't science fiction, it's real."

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Entire Genetic Sequence of Individual Human Sperm Determined

Entire Genetic Sequence of Individual Human Sperm Determined

  11:46:00 AM    Science Lover

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The entire genomes of 91 human sperm from one man have been sequenced by Stanford University researchers. The results provide a fascinating glimpse into naturally occurring genetic variation in one individual, and are the first to report the whole-genome sequence of a human gamete -- the only cells that become a child and through which parents pass on physical traits.

Every sperm cell looks essentially the same, with that characteristic tadpole appearance. But inside, sperm cells carry differences within their genes -- even cells from the same man. Now, researchers provide a detailed picture of how the cell's DNA varies in a new study published in the July 20, 2012 issue of the Cell Press journal Cell. The techniques used could be helpful for understanding male reproductive disorders or, when applied to other areas of research, for characterizing normal and diseased cells in the body. (Credit: iStockphoto/Alexandr Mitiuc)

"This represents the culmination of nearly a decade of work in my lab," said Stephen Quake, PhD, the Lee Otterson Professor in the School of Engineering and professor of bioengineering and of applied physics. "We now have devices that will allow us to routinely amplify and sequence to a high degree of accuracy the entire genomes of single cells, which has far-ranging implications for the study of cancer, infertility and many other disorders."

Quake is the senior author of the research, published July 20 in Cell. Graduate student Jianbin Wang and former graduate student H. Christina Fan, PhD, now a senior scientist at ImmuMetrix, share first authorship of the paper.

Sequencing sperm cells is particularly interesting because of a natural process called recombination that ensures that a baby is a blend of DNA from all four of his or her grandparents. Until now, scientists had to rely on genetic studies of populations to estimate how frequently recombination had occurred in individual sperm and egg cells, and how much genetic mixing that entailed.

"Single-sperm sequencing will allow us to chart and understand how recombination differs between individuals at the finest scales. This is an important proof of principle that will allow us to study both fundamental dynamics of recombination in humans and whether it is involved in issues relating to male infertility," said Gilean McVean, PhD, professor of statistical genetics at the Wellcome Trust Centre for Human Genetics. McVean was not involved in the research.

The Stanford study showed that the previous, population-based estimates were, for the most part, surprisingly accurate: on average, the sperm in the sample had each undergone about 23 recombinations, or mixing events. However, individual sperm varied greatly in the degree of genetic mixing and in the number and severity of spontaneously arising genetic mutations. Two sperm were missing entire chromosomes. The study has long-ranging implication for infertility doctors and researchers.

"For the first time, we were able to generate an individual recombination map and mutation rate for each of several sperm from one person," said study co-author Barry Behr, PhD, HCLD, professor of obstetrics and gynecology and director of Stanford's in vitro fertilization laboratory. "Now we can look at a particular individual, make some calls about what they would likely contribute genetically to an embryo and perhaps even diagnose or detect potential problems."

Most cells in the human body have two copies of each of 23 chromosomes, and are known as "diploid" cells. Recombination occurs during a process called meiosis, which partitions a single copy of each chromosome into a sperm (in a man) or egg (in a woman) cell. When a sperm and an egg join, the resulting fertilized egg again has a full complement of DNA.

To ensure an orderly distribution during recombination, pairs of chromosomes are lined up in tight formation along the midsection of the cell. During this snug embrace, portions of matching chromosomes are sometimes randomly swapped. The process generates much more genetic variation in a potential offspring than would be possible if only intact chromosomes were segregated into the reproductive cells.

"The exact sites, frequency and degree of this genetic mixing process is unique for each sperm and egg cell," said Quake, "and we've never before been able to see it with this level of detail. It's very interesting that what happens in one person's body mirrors the population average."

Major problems with the recombination process can generate sperm missing portions or even whole chromosomes, making them incapable of or unlikely to fertilize an egg. But it can be difficult for fertility researchers to identify potential problems.

"Most of the techniques we currently use to assess sperm viability are fairly crude," said Quake.

To conduct the research, Wang, Quake and Behr first isolated and sequenced nearly 100 sperm cells from the study subject, a 40-year-old man. The man has healthy offspring, and the semen sample appeared normal. His whole-genome sequence (obtained from diploid cells) has been previously sequenced to a high level of accuracy.

They then compared the sequence of the sperm with that of the study subject's diploid genome. They could see, by comparing the sequences of the chromosomes in the diploid cells with those in the haploid sperm cells, where each recombination event took place. The researchers also identified 25 to 36 new single nucleotide mutations in each sperm cell that were not present in the subject's diploid genome. Such random mutations are another way to generate genetic variation, but if they occur at particular points in the genome they can have deleterious effects.

It's important to note that individual sperm cells are destroyed by the sequencing process, meaning that they couldn't go on to be used for fertilization. However, the single-cell sequencing described in the paper could potentially be used to diagnose male reproductive disorders and help infertile couples assess their options. It could also be used to learn more about how male fertility and sperm quality change with increasing age.

"This could serve as a new kind of early detection system for men who may have reproductive problems," said Behr, who also co-directs Stanford's reproductive endocrinology and infertility program. "It's also possible that we could one day use other, correlating features to harmlessly identify healthy sperm for use in IVF. In the end, the DNA is the raw material that ultimately defines a sperm's potential. If we can learn more about this process, we can better understand human fertility."

The research was supported by the National Institute of Health, the Chinese Scholarship Council and the Siebel Foundation.

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A Wrinkle in Space-Time: Math Shows How Shockwaves Could Crinkle Space

A Wrinkle in Space-Time: Math Shows How Shockwaves Could Crinkle Space

  11:20:00 AM    Science Lover

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Mathematicians at UC Davis have come up with a new way to crinkle up the fabric of space-time -- at least in theory.

Illustration of twisted space-time around Earth. (Credit: NASA)

"We show that space-time cannot be locally flat at a point where two shock waves collide," said Blake Temple, professor of mathematics at UC Davis. "This is a new kind of singularity in general relativity."

The results are reported in two papers by Temple with graduate students Moritz Reintjes and Zeke Vogler, respectively, both published in the journal Proceedings of the Royal Society A.

Einstein's theory of general relativity explains gravity as a curvature in space-time. But the theory starts from the assumption that any local patch of space-time looks flat, Temple said.

A singularity is a patch of space-time that cannot be made to look flat in any coordinate system, Temple said. One example of a singularity is inside a black hole, where the curvature of space becomes extreme.

Temple and his collaborators study the mathematics of how shockwaves in a perfect fluid can affect the curvature of space-time in general relativity. In earlier work, Temple and collaborator Joel Smoller, Lamberto Cesari professor of mathematics at the University of Michigan, produced a model for the biggest shockwave of all, created from the Big Bang when the universe burst into existence.

A shockwave creates an abrupt change, or discontinuity, in the pressure and density of a fluid, and this creates a jump in the curvature. But it has been known since the 1960s that the jump in curvature created by a single shock wave is not enough to rule out the locally flat nature of space-time.

Vogler's doctoral work used mathematics to simulate two shockwaves colliding, while Reintjes followed up with an analysis of the equations that describe what happens when shockwaves cross. He found this created a new type of singularity, which he dubbed a "regularity singularity."

What is surprising is that something as mild as interacting waves could create something as extreme as a space-time singularity, Temple said.

Temple and his colleagues are investigating whether the steep gradients in the space-time fabric at a regularity singularity could create any effects that are measurable in the real world. For example, they wonder whether they might produce gravity waves, Temple said. General relativity predicts that these are produced, for example, by the collision of massive objects like black holes, but they have not yet been observed in nature. Regularity singularities could also be formed within stars as shockwaves pass within them, the researchers theorize.

Reintjes, now a postdoctoral scholar at the University of Regensburg, Germany presented the work at the International Congress on Hyperbolic Problems in Padua, in June.

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Visual Searches: Human Brain Beats Computers

Visual Searches: Human Brain Beats Computers

  8:48:00 PM    Science Lover

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You're headed out the door and you realize you don't have your car keys. After a few minutes of rifling through pockets, checking the seat cushions and scanning the coffee table, you find the familiar key ring and off you go. Easy enough, right? What you might not know is that the task that took you a couple seconds to complete is a task that computers -- despite decades of advancement and intricate calculations -- still can't perform as efficiently as humans: the visual search.

Part of the research team in front of the Magnetic Resonance Imaging (MRI) device at the UCSB Brain Imaging Center From left to right : Researcher Tim Preston; Associate Professor of Psychological & Brain Sciences Barry Giesbrecht; and Professor of Psychological & Brain Sciences Miguel P. Eckstein. Not pictured: Koel Das, now a faculty member at the Indian Institute of Science in Bangalore, Karnatka, India; and lead author Fei Guo, now in the software industry. (Credit: Image courtesy of University of California - Santa Barbara)

"Our daily lives are composed of little searches that are constantly changing, depending on what we need to do," said Miguel Eckstein, UC Santa Barbara professor of psychological and brain sciences and co-author of the recently released paper "Feature-Independent Neural Coding of Target Detection during Search of Natural Scenes," published in the Journal of Neuroscience. "So the idea is, where does that take place in the brain?"

A large part of the human brain is dedicated to vision, with different parts involved in processing the many visual properties of the world. Some parts are stimulated by color, others by motion, yet others by shape.

However, those parts of the brain tell only a part of the story. What Eckstein and co-authors wanted to determine was how we decide whether the target object we are looking for is actually in the scene, how difficult the search is, and how we know we've found what we wanted.

They found their answers in the dorsal frontoparietal network, a region of the brain that roughly corresponds to the top of one's head, and is also associated with properties such as attention and eye movements. In the parts of the human brain used earlier in the processing stream, regions stimulated by specific features like color, motion, and direction are a major part of the search. However, in the dorsal frontoparietal network, activity is not confined to any specific features of the object.

"It's flexible," said Eckstein. Using 18 observers, an MRI machine, and hundreds of photos of scenes flashed before the observers with instructions to look for certain items, the scientists monitored their subjects' brain activity. By watching the intraparietal sulcus (IPS), located within the dorsal frontoparietal network, the researchers were able to note not only whether their subjects found the objects, but also how confident they were in their finds.

The IPS region would be stimulated even if the object was not there, said Eckstein, but the pattern of activity would not be the same as it would had the object actually existed in the scene. The pattern of activity was consistent, even though the 368 different objects the subjects searched for were defined by very different visual features. This, Eckstein said, indicates that IPS did not rely on the presence of any fixed feature to determine the presence or absence of various objects. Other visual regions did not show this consistent pattern of activity across objects.

"As you go further up in processing, the neurons are less interested in a specific feature, but they're more interested in whatever is behaviorally relevant to you at the moment," said Eckstein. Thus, a search for an apple, for instance, would make red, green, and rounded shapes relevant. If the search was for your car keys, the interparietal sulcus would now be interested in gold, silver, and key-type shapes and not interested in green, red, and rounded shapes.

"For visual search to be efficient, we want those visual features related to what we are looking for to elicit strong responses in our brain and not others that are not related to our search, and are distracting," Eckstein added. "Our results suggest that this is what is achieved in the intraparietal sulcus, and allows for efficient visual search."

For Eckstein and colleagues, these findings are just the tip of the iceberg. Future research will dig more deeply into the seemingly simple yet essential ability of humans to do a visual search and how they can use the layout of a scene to guide their search.

"What we're trying to really understand is what other mechanisms or strategies the brain has to make searches efficient and easy," said Eckstein. "What part of the brain is doing that?"

Research on this study was also conducted by Tim Preston, Koel Das, Barry Giesbrecht, and first author Fei Guo, all from UC Santa Barbara.

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Diabetes Drug Makes Brain Cells Grow

Diabetes Drug Makes Brain Cells Grow

  2:00:00 PM    Science Lover

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The widely used diabetes drug metformin comes with a rather unexpected and alluring side effect: it encourages the growth of new neurons in the brain. The study reported in the July 6th issue of Cell Stem Cell, a Cell Press publication, also finds that those neural effects of the drug also make mice smarter.

New research finds that the widely used diabetes drug 
metformin comes with a rather unexpected and alluring 
side effect: it encourages the growth of new neurons in 
the brain. (Credit: iStockphoto/Guido Vrola)

The discovery is an important step toward therapies that aim to repair the brain not by introducing new stem cells but rather by spurring those that are already present into action, says the study's lead author Freda Miller of the University of Toronto-affiliated Hospital for Sick Children. The fact that it's a drug that is so widely used and so safe makes the news all that much better.

Earlier work by Miller's team highlighted a pathway known as aPKC-CBP for its essential role in telling neural stem cells where and when to differentiate into mature neurons. As it happened, others had found before them that the same pathway is important for the metabolic effects of the drug metformin, but in liver cells.

"We put two and two together," Miller says. If metformin activates the CBP pathway in the liver, they thought, maybe it could also do that in neural stem cells of the brain to encourage brain repair.

The new evidence lends support to that promising idea in both mouse brains and human cells. Mice taking metformin not only showed an increase in the birth of new neurons, but they were also better able to learn the location of a hidden platform in a standard maze test of spatial learning.

While it remains to be seen whether the very popular diabetes drug might already be serving as a brain booster for those who are now taking it, there are already some early hints that it may have cognitive benefits for people with Alzheimer's disease. It had been thought those improvements were the result of better diabetes control, Miller says, but it now appears that metformin may improve Alzheimer's symptoms by enhancing brain repair.

Miller says they now hope to test whether metformin might help repair the brains of those who have suffered brain injury due to trauma or radiation therapies for cancer.

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Houdini-Like Vanishing Act in Space

Houdini-Like Vanishing Act in Space

  11:19:00 AM    Science Lover

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Astronomers report a baffling discovery never seen before: An extraordinary amount of dust around a nearby star has mysteriously disappeared.

Dust today, gone tomorrow. An artist's conceptualization 
of the dusty TYC 8241 2652 system as it may have appeared 
several years ago, when it was emitting large amounts of 
excess infrared radiation. (Credit: Gemini Observatory/
AURA artwork by Lynette Cook))

"It's like the classic magician's trick -- now you see it, now you don't," said Carl Melis, a postdoctoral scholar at UC San Diego and lead author of the research. "Only in this case, we're talking about enough dust to fill an inner solar system, and it really is gone!"

"It's as if the rings around Saturn had disappeared," said co-author Benjamin Zuckerman, a UCLA professor of physics and astronomy. "This is even more shocking because the dusty disc of rocky debris was bigger and much more massive than Saturn's rings. The disc around this star, if it were in our solar system, would have extended from the sun halfway out to Earth, near the orbit of Mercury."

The research on this cosmic vanishing act, which occurred around a star some 450 light years from Earth, in the direction of the constellation Centaurus, appears July 5 in the journal Nature.

"A perplexing thing about this discovery is that we don't have a satisfactory explanation to address what happened around this star," said Melis, a former UCLA astronomy graduate student. "The disappearing act appears to be independent of the star itself, as there is no evidence to suggest that the star zapped the dust with some sort of mega-flare or any other violent event."

Melis describes the star, designated TYC 8241 2652, as a "young analog of our sun" that only a few years ago displayed all of the characteristics of "hosting a solar system in the making," before transforming completely. Now, very little of the warm, dusty material thought to originate from collisions of rocky planets is apparent.

"Nothing like this has ever been seen in the many hundreds of stars that astronomers have studied for dust rings," Zuckerman said. "This disappearance is remarkably fast, even on a human time scale, much less an astronomical scale. The dust disappearance at TYC 8241 2652 was so bizarre and so quick, initially I figured that our observations must simply be wrong in some strange way."

Norm Murray, director of the Canadian Institute for Theoretical Astrophysics, who was not part of the research group, said, "The history of astronomy has shown that events that are not predicted and hard to explain can be game-changers."

The dust had been present around the star since at least 1983 (no one had observed the star in the infrared before then), and it continued to glow brightly in the infrared for 25 years. In 2009, it started to dim. By 2010, the dust emission was gone; the astronomers observed the star twice that year from the Gemini Observatory in Chile, six months apart. An infrared image obtained by the Gemini telescope as recently as May 1 of this year confirmed that the warm dust has now been gone for two-and-a-half years.

Like Earth, warm dust absorbs the energy of sunlight and re-radiates that heat energy as infrared radiation.

Because so much dust had been orbiting around the star, planets very likely are forming there, said Zuckerman, whose research is funded by NASA.

The lack of an existing model for what is going on around this star is forcing astronomers to rethink what happens within young solar systems in the making. The dust likely resulted from a violent collision -- but that would not explain where it went. Was it somehow swallowed by the star?

"Although we've identified a couple of mechanisms that are potentially viable, none are really compelling," Melis said. "In one case, gas produced in the impact that released the dust helps to quickly drag the dust particles into the star and thus to their doom. In another possibility, collisions of large rocks left over from an original major impact provide a fresh infusion of dust particles into the disc, which then instigate a runaway process where small grains chip into oblivion both themselves and also larger grains."

Major dusty regions are known to exist in our own solar system and include the asteroid belt between the orbits of Mars and Jupiter and another located beyond the orbit of Neptune. Nearly 30 years ago, NASA's Infrared Astronomical Satellite (IRAS) first discovered many similar regions orbiting other stars -- but no disappearing act like the one at TYC 8241 2652 has ever been seen during these three decades.

The research is based on multiple sets of observations of TYC 8241 2652 obtained with the Thermal-Region Camera Spectrograph on the Gemini South telescope in Chile, the IRAS, NASA's Wide-field Infrared Survey Explorer (WISE) satellite, NASA's Infrared Telescope on Mauna Kea in Hawaii, the Herschel Space Telescope of the European Space Agency (ESA), and AKARI (a Japanese/ESA infrared satellite).

"We were lucky to catch this disappearing act," Zuckerman said. "Such events could be relatively common, without our knowing it."

Co-authors of the Nature paper are Joseph Rhee, a former UCLA postdoctoral scholar in astronomy, who is now an astronomer at California State Polytechnic University in Pomona; Inseok Song, an assistant professor of physics and astronomy at the University of Georgia who also was a postdoctoral researcher at UCLA; and astronomers Simon Murphy and Michael Bessell at the Australian National University.

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