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An anonymous reader writes "According to Wired, 'Today's big data is noisy, unstructured, and dynamic rather than static. It may also be corrupted or incomplete. ... researchers need new mathematical tools in order to glean useful information from the data sets. "Either you need a more sophisticated way to translate it into vectors, or you need to come up with a more generalized way of analyzing it," [Mathematician Jesse Johnson] said. One such new math tool is described later: "... a mathematician at Stanford University, and his then-postdoc ... were fiddling with a badly mangled image on his computer ... They were trying to find a method for improving fuzzy images, such as the ones generated by MRIs when there is insufficient time to complete a scan. On a hunch, Candes applied an algorithm designed to clean up fuzzy images, expecting to see a slight improvement. What appeared on his computer screen instead was a perfectly rendered image. Candes compares the unlikeliness of the result to being given just the first three digits of a 10-digit bank account number, and correctly guessing the remaining seven digits. But it wasn't a fluke. The same thing happened when he applied the same technique to other incomplete images. The key to the technique's success is a concept known as sparsity, which usually denotes an image's complexity, or lack thereof. It's a mathematical version of Occam's razor: While there may be millions of possible reconstructions for a fuzzy, ill-defined image, the simplest (sparsest) version is probably the best fit. Out of this serendipitous discovery, compressed sensing was born.'"

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John Timmer

Arthur Toga, University of California, Los Angeles

In 1992, at the age of 70, a US citizen suffered a severe case of viral encephalitis, a swelling of the brain caused by infection. After he recovered two years later, he appeared completely average based on an IQ test (indeed, he scored 103). Yet in other ways, he was completely different. Several decades of his past life were wiped completely from his brain. His only accessible memories came from his 30s, and from the point of his illness to his death, he would never form another memory that he was aware of.

But this severe case of what appears to be total amnesia doesn't mean he had no memory as we commonly understand it. The patient, called E.P., was studied intensely using a battery of tests for more than a decade, with researchers giving him tests during hundreds of sessions. After his death, his brain was given for further study. With the analysis of the brain complete, the people who studied him have taken the opportunity to publish a review of all his complex memory problems.

Aside from memory, there were only a few obvious problems with E.P. Most of his senses were normal except smell, which was wiped out (a condition called anosmia). His vision was perfectly fine, but he had two specific problems interpreting what he saw. One was a limited ability to discriminate between faces, and the other was difficulty in determining whether a line drawing represented an object that's physically impossible (think M. C. Escher drawings).

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I've been a Microsoft developer for decades now. I weaned myself on various flavors of home computer Microsoft Basic, and I got my first paid programming gigs in Microsoft FoxPro, Microsoft Access, and Microsoft Visual Basic. I have seen the future of programming, my friends, and it is terrible CRUD apps running on Wintel boxes!

Of course, we went on to build Stack Overflow in Microsoft .NET. That's a big reason it's still as fast as it is. So one of the most frequently asked questions after we announced Discourse was:

Why didn't you build Discourse in .NET, too?

Let me be clear about something: I love .NET. One of the greatest thrills of my professional career was getting the opportunity to place a Coding Horror sticker in the hand of Anders Hejlsberg. Pardon my inner fanboy for a moment, but oh man I still get chills. There are maybe fifty world class computer language designers on the planet. Anders is the only one of them who built Turbo Pascal and Delphi. It is thanks to Anders' expert guidance that .NET started out such a remarkably well designed language – literally what Java should have been on every conceivable level – and has continued to evolve in remarkably practical ways over the last 10 years, leveraging the strengths of other influential dynamically typed languages.

Turbo-pascal

All that said, it's true that I intentionally chose not to use .NET for my next project. So you might expect to find an angry, righteous screed here about how much happier I am leaving the oppressive shackles of my Microsoft masters behind. Free at last, free at least, thank God almighty I'm free at last!

Sorry. I already wrote that post five years ago.

Like any pragmatic programmer, I pick the appropriate tool for the job at hand. And as much as I may love .NET, it would be an extraordinarily poor choice for an 100% open source project like Discourse. Why? Three reasons, mainly:

  1. The licensing. My God, the licensing. It's not so much the money, as the infernal, mind-bending tax code level complexity involved in making sure all your software is properly licensed: determining what 'level' and 'edition' you are licensed at, who is licensed to use what, which servers are licensed... wait, what? Sorry, I passed out there for a minute when I was attacked by rabid licensing weasels.

    I'm not inclined to make grand pronouncements about the future of software, but if anything kills off commercial software, let me tell you, it won't be open source software. They needn't bother. Commercial software will gleefully strangle itself to death on its own licensing terms.

  2. The friction. If you want to build truly viable open source software, you need people to contribute to your project, so that it is a living, breathing, growing thing. And unless you can download all the software you need to hack on your project freely from all over the Internet, no strings attached, there's just … too much friction.

    If Stack Overflow taught me anything, it is that we now live in a world where the next brilliant software engineer can come from anywhere on the planet. I'm talking places this ugly American programmer has never heard of, where they speak crazy nonsense moon languages I can't understand. But get this. Stand back while I blow your mind, people: these brilliant programmers still code in the same keywords we do! I know, crazy, right?

Getting up and running with a Microsoft stack is just plain too hard for a developer in, say, Argentina, or Nepal, or Bulgaria. Open source operating systems, languages, and tool chains are the great equalizer, the basis for the next great generation of programmers all over the world who are going to help us change the world.

  • The ecosystem. When I was at Stack Exchange we strove mightily to make as much of our infrastructure open source as we could. It was something that we made explicit in the compensation guidelines, this idea that we would all be (partially) judged by how much we could do in public, and try to leave behind as many useful, public artifacts of our work as we could. Because wasn't all of Stack Exchange itself, from the very first day, built on your Creative Commons contributions that we all share ownership of?

    You can certainly build open source software in .NET. And many do. But it never feels natural. It never feels right. Nobody accepts your patch to a core .NET class library no matter how hard you try. It always feels like you're swimming upstream, in a world of small and large businesses using .NET that really aren't interested in sharing their code with the world – probably because they know it would suck if they did, anyway. It is just not a native part of the Microsoft .NET culture to make things open source, especially not the things that suck. If you are afraid the things you share will suck, that fear will render you incapable of truly and deeply giving back. The most, uh, delightful… bit of open source communities is how they aren't afraid to let it "all hang out", so to speak.

    So as a result, for any given task in .NET you might have – if you're lucky – a choice of maybe two decent-ish libraries. Whereas in any popular open source language, you'll easily have a dozen choices for the same task. Yeah, maybe six of them will be broken, obsolete, useless, or downright crazy. But hey, even factoring in some natural open source spoilage, you're still ahead by a factor of three! A winner is you!

  • As I wrote five years ago:

    I'm a pragmatist. For now, I choose to live in the Microsoft universe. But that doesn't mean I'm ignorant of how the other half lives. There's always more than one way to do it, and just because I chose one particular way doesn't make it the right way – or even a particularly good way. Choosing to be provincial and insular is a sure-fire path to ignorance. Learn how the other half lives. Get to know some developers who don't live in the exact same world you do. Find out what tools they're using, and why. If, after getting your feet wet on both sides of the fence, you decide the other half is living better and you want to join them, then I bid you a fond farewell.

    I no longer live in the Microsoft universe any more. Right, wrong, good, evil, that's just how it turned out for the project we wanted to build.

    Im-ok-with-this

    However, I'd also be lying if I didn't mention that I truly believe the sort of project we are building in Discourse does represent most future software. If you squint your eyes a little, I think you can see a future not too far in the distance where .NET is a specialized niche outside the mainstream.

    But why Ruby? Well, the short and not very glamorous answer is that I had narrowed it down to either Python or Ruby, and my original co-founder Robin Ward has been building major Rails apps since 2006. So that clinched it.

    I've always been a little intrigued by Ruby, mostly because of the absolutely gushing praise Steve Yegge had for the language way back in 2006. I've never forgotten this.

    For the most part, Ruby took Perl's string processing and Unix integration as-is, meaning the syntax is identical, and so right there, before anything else happens, you already have the Best of Perl. And that's a great start, especially if you don't take the Rest of Perl.

    But then Matz took the best of list processing from Lisp, and the best of OO from Smalltalk and other languages, and the best of iterators from CLU, and pretty much the best of everything from everyone.

    And he somehow made it all work together so well that you don't even notice that it has all that stuff. I learned Ruby faster than any other language, out of maybe 30 or 40 total; it took me about 3 days before I was more comfortable using Ruby than I was in Perl, after eight years of Perl hacking. It's so consistent that you start being able to guess how things will work, and you're right most of the time. It's beautiful. And fun. And practical.

    Steve is one of those polyglot programmers I respect so much that I basically just take whatever his opinion is, provided it's not about something wacky like gun control or feminism or T'Pau, and accept it as fact.

    I apologize, Steve. I'm sorry it took me 7 years to get around to Ruby. But maybe I was better off waiting a while anyway:

    • Ruby is a decent performer, but you really need to throw fast hardware at it for good performance. Yeah, I know, interpreted languages are what they are, and caching, database, network, blah blah blah. Still, we obtained the absolute fastest CPUs you could buy for the Discourse servers, 4.0 Ghz Ivy Bridge Xeons, and performance is just … good on today's fastest hardware. Not great. Good.

      Yes, I'll admit that I am utterly spoiled by the JIT compiled performance of .NET. That's what I am used to. I do sometimes pine away for the bad old days of .NET when we could build pages that serve in well under 50 milliseconds without thinking about it too hard. Interpreted languages aren't going to be able to reach those performance levels. But I can only imagine how rough Ruby performance had to be back in the dark ages of 2006 when CPUs and servers were five times slower than they are today! I'm so very glad that I am hitting Ruby now, with the strong wind of many solid years of Moore's law at our backs.

  • Ruby is maturing up nicely in the 2.0 language release, which happened not more than a month after Discourse was announced. So, yes, the downside is that Ruby is slow. But the upside is there is a lot of low hanging performance fruit in Ruby-land. Like.. a lot a lot. On Discourse we got an across the board 20% performance improvement just upgrading to Ruby 2.0, and we nearly doubled our performance by increasing the default Ruby garbage collection limit. From a future performance perspective, Ruby is nothing but upside.

  • Ruby isn't cool any more. Yeah, you heard me. It's not cool to write Ruby code any more. All the cool people moved on to slinging Scala and Node.js years ago. Our project isn't cool, it's just a bunch of boring old Ruby code. Personally, I'm thrilled that Ruby is now mature enough that the community no longer needs to bother with the pretense of being the coolest kid on the block. That means the rest of us who just like to Get Shit Done can roll up our sleeves and focus on the mission of building stuff with our peers rather than frantically running around trying to suss out the next shiny thing.

    And of course the Ruby community is, and always has been, amazing. We never want for great open source gems and great open source contributors. Now is a fantastic time to get into Ruby, in my opinion, whatever your background is.

    (However, It's also worth mentioning that Discourse is, if anything, even more of a JavaScript project than a Ruby on Rails project. Don't believe me? Just go to try.discourse.org and view source. A Discourse forum is not so much a website as it is a full-blown JavaScript application that happens to run in your browser.)

    Even if done in good will and for the best interests of the project, it's still a little scary to totally change your programming stripes overnight after two decades. I've always believed that great programmers learn to love more than one language and programming environment – and I hope the Discourse project is an opportunity for everyone to learn and grow, not just me. So go fork us on GitHub already!

    [advertisement] Hiring developers? Post your open positions with Stack Overflow Careers and reach over 20MM awesome devs already on Stack Overflow. Create your satisfaction-guaranteed job listing today!

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    waderoush writes "In November, Lytro, the maker of the first light field camera for consumers, upgraded its viewer software to enable a feature called 'Perspective Shift.' In addition to refocusing pictures after they've been taken, Lytro audiences can now pivot between different virtual points of view, within a narrow baseline. This 3-D capability was baked into Lytro's technology from the start: 'The light field itself is inherently multidimensional [and] the 2-D refocusable picture that we launched with was just one way to represent that,' says Eric Cheng, Lytro's director of photography. But while Perspective Shift is currently little more than a novelty, the possibilities for future 3-D imaging are startling, especially as Lytro develops future devices with larger sensors — and therefore larger baselines, allowing more dramatic 3-D effects. Cheng says the company is already exploring future versions of its viewer software that would work on 3-D televisions. 'We are moving the power of photography from optics to computation,' he says. 'So when the public really demands 3-D content, we will be ready for it.'"

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    Is it worth bluffing if you're playing cards against a computer? Most of us go through the day reading subtle (and some not-so-subtle) social cues, like tone of voice, body language, and facial expressions, to figure out what an appropriate course of action should be. To look into how humans read some of these social cues, researchers have put subjects into an MRI tube and asked them to play a simplified form of poker (just one card) against both computerized and human opponents.

    The participants kept track of their opponents' behavior on previous trials when determining whether to bluff with a given card, but were more careful to pay attention to what their human opponents did. The researchers then used MRI images of brain activity to look for areas of the brain that might mediate this difference. One area stood out: the temporal-parietal junction, or TPJ.

    (Functional MRI studies have come in for some criticism because the researchers often focus imaging on areas they expect to see involved. In this case, the researchers imaged the whole brain, divided it up evenly, and repeated the search for elevated activity. The TPJ still stood out.)

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    Fred Wilson and Friends

    Starting a company is hard, so you're going to need a lot of advice along the way.

    There are many entrepreneurs, investors and bloggers who churn out business advice daily, but it's a pain figuring out which sites are worth reading.

    We've compiled a list of our favorite sources of small business and tech news for entrepreneurs.

    Running the gamut from hilarious, to informational, to controversial, to thought-provoking, these blogs are all must-reads for anyone who's running a business.

    Quora

    Blog: Quora

    Blogger: Any entrepreneur you want to follow, from Fred Wilson to Marc Cuban

    Why it's so great: Quora is a Q&A site where experts actually take the time to seriously answer your questions. You can follow topics like "startups" and "entrepreneurship" and people like Fred Wilson or Mark Zuckerberg.  Answers get voted up by by the community so that only the best ones shine. You can find answers to questions like "What is the best way to prepare yourself for entrepreneurship?" or "What are some tips on connecting with high-profile people that can help your startup?"

    Sample: "What are some tips on connecting with high-profile people that can help your startup?"

    Top answer by Robert Scoble:

    I hang around high-profile people often. Here's some things that can help you connect:

    1. Listen. If they say your idea sucks, listen to the feedback, take notes, and ask for contact info. Then go fix the problems, or come up with another idea and demonstrate you listened.
    2. Get to the point. People like Ron Conway are busy. They are wildly rich, so the only thing that is limited in their life is time. You are taking away some of their most precious resource, so get to the freaking point. Don't try to chit chat or ask about their kids or make small talk. Go right for the big ask. They are used to it.

    PandoDaily

    Blog: PandoDaily

    Blogger: Sarah Lacy

    Why it's so great: Sarah Lacy and her band of bloggers at Pando are making an effort to become the "site of record for Silicon Valley." Much of the staff came from TechCrunch, so they're well sourced. Lacy conducts exclusive interviews with high profile people in tech and curates the top tech/entrepreneurship stories from other startups in the site's right rail.

    Sample: AngelList has Transformed Seed Investing -- Are Recruiters and Job Boards Next?

    Last week Naval Ravikant went to an industry dinner. He asked a friend in the venture business how things were going. The friend slumped over in his chair, shrugged sadly and said, “The business is becoming commoditized.”

    It’s an extreme interpretation, and not everyone shares it. Times have never been better for a handful of firms who are rolling in the returns, raising as much from LPs as they want and still doing business the way they always have.

    But matters have also never been more polarized for the VC-haves and have-nots, and this sad-sack VC has a few people to blame. Chief among them is his friend Ravikant, whose site AngelList has dragged the stealthy, back-room world of venture capital kicking and screaming into the light — something many industry watchers never thought could be done.

    And now, AngelList is doing the same thing it did to VCs to recruiters.

    LinkedIn Today

    Blog: LinkedIn Today

    Blogger: LinkedIn curates articles based on your professional profile and your social connections.

    Why it's so great: LinkedIn Today curates articles that are fitting for your industry and that people in that industry are sharing. As such, it's a good source of entrepreneurship and business news all in one place.

    Sample: Articles on LinkedIn Today:

    Hiring Your First Set Of Employees - Greylock Capital

    Facebook Testing a New 'Want' Button - Inside Facebook

    See the rest of the story at Business Insider

    Please follow War Room on Twitter and Facebook.

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    [ By WebUrbanist in Conceptual & Futuristic & Technology. ]

    Nothing moves faster than light, right? True as that may be in theory, a team at MIT has developed a method for visualizing its propagation to amazing effect in practice.

    Slowed down and turned into film format, an illuminated tomato goes from ordinary to uncanny as a snaking arc of white light approaches in a billionth-of-a-second burst, then deforms to move across it, with an unrivaled FPS rate.

    And the impact goes beyond making neat little films: “Beyond the potential in artistic and educational visualization, applications include industrial imaging to analyze faults and material properties, scientific imaging for understanding ultrafast processes and medical imaging to reconstruct sub-surface elements.”

    So how does it work? Per their abstract: “The effective exposure time of each frame is two trillionths of a second and the resultant visualization depicts the movement of light at roughly half a trillion frames per second. Direct recording of reflected or scattered light at such a frame rate with sufficient brightness is nearly impossible. We use an indirect ‘stroboscopic’ method that records millions of repeated measurements by careful scanning in time and viewpoints. Then we rearrange the data to create a ‘movie’ of a nanosecond long event.”

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