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Fri, 05/29/2015 - 7:27am
Helen Knight, MIT News correspondent
Image: Christine Daniloff/MIT
Memories that have been “lost” as a result of amnesia can be recalled by activating brain cells with light. In a paper published in Science, researchers at Massachusetts Institute of Technology (MIT) reveal that they were able to reactivate memories that could not otherwise be retrieved, using a technology known as optogenetics. The finding answers a fiercely debated question in neuroscience as to the nature of amnesia, according to Susumu Tonegawa, the Picower Professor in MIT’s Dept. of Biology and director of the RIKEN-MIT Center at the Picower Institute for Learning and Memory, who directed the research by lead authors Tomas Ryan, Dheeraj Roy and Michelle Pignatelli. Neuroscience researchers have for many years debated whether retrograde amnesia—which follows traumatic injury, stress, or diseases such as Alzheimer’s—is caused by damage to specific brain cells, meaning a memory cannot be stored, or if access to that memory is somehow blocked, preventing its recall. “The majority of researchers have favored the storage theory, but we have shown in this paper that this majority theory is probably wrong,” Tonegawa says. “Amnesia is a problem of retrieval impairment.” Memory researchers have previously speculated that somewhere in the brain network is a population of neurons that are activated during the process of acquiring a memory, causing enduring physical or chemical changes. If these groups of neurons are subsequently reactivated by a trigger such as a particular sight or smell, for example, the entire memory is recalled. These neurons are known as “memory engram cells.” Shedding light In 2012 Tonegawa’s group used optogenetics—in which proteins are added to neurons to allow them to be activated with light—to demonstrate for the first time that such a population of neurons does indeed exist in an area of the brain called the hippocampus. However, until now no one has been able to show that these groups of neurons do undergo enduring chemical changes, in a process known as memory consolidation. One such change, known as “long-term potentiation” (LTP), involves the strengthening of synapses, the structures that allow groups of neurons to send signals to each other, as a result of learning and experience. To find out if these chemical changes do indeed take place, the researchers first identified a group of engram cells in the hippocampus that, when activated using optogenetic tools, were able to express a memory. When they then recorded the activity of this particular group of cells, they found that the synapses connecting them had been strengthened. “We were able to demonstrate for the first time that these specific cells—a small group of cells in the hippocampus—had undergone this augmentation of synaptic strength,” Tonegawa says. The researchers then attempted to discover what happens to memories without this consolidation process. By administering a compound called anisomycin, which blocks protein synthesis within neurons, immediately after mice had formed a new memory, the researchers were able to prevent the synapses from strengthening. When they returned one day later and attempted to reactivate the memory using an emotional trigger, they could find no trace of it. “So even though the engram cells are there, without protein synthesis those cell synapses are not strengthened, and the memory is lost,” Tonegawa says. But startlingly, when the researchers then reactivated the protein synthesis-blocked engram cells using optogenetic tools, they found that the mice exhibited all the signs of recalling the memory in full. “If you test memory recall with natural recall triggers in an anisomycin-treated animal, it will be amnesiac, you cannot induce memory recall,” Tonegawa says. “But if you go directly to the putative engram-bearing cells and activate them with light, you can restore the memory, despite the fact that there has been no LTP.” “Groundbreaking paper” Further studies carried out by Tonegawa’s group demonstrated that memories are stored not in synapses strengthened by protein synthesis in individual engram cells, but in a circuit, or “pathway” of multiple groups of engram cells and the connections between them. “We are proposing a new concept, in which there is an engram cell ensemble pathway, or circuit, for each memory,” he says. “This circuit encompasses multiple brain areas and the engram cell ensembles in these areas are connected specifically for a particular memory.” The research dissociates the mechanisms used in memory storage from those of memory retrieval, according to Ryan. “The strengthening of engram synapses is crucial for the brain’s ability to access or retrieve those specific memories, while the connectivity pathways between engram cells allows the encoding and storage of the memory information itself,” he says. Changes in synaptic strength and in spine properties have long been associated with learning and memory, according to Alcino Silva, director of the Integrative Center for Learning and Memory at the Univ. of California at Los Angeles. “This groundbreaking paper suggests that these changes may not be as critical for memory as once thought, since under certain conditions, it seems to be possible to disrupt these changes and still preserve memory,” he says. “Instead, it appears that these changes may be needed for memory retrieval, a mysterious process that has so far evaded neuroscientists.” Source: Massachusetts Institute of Technology |
domingo, 31 de maio de 2015
Researchers find “lost” memories
5 Things That Absolutely Kill Your Productivity
Martin Barraud / OJO Images / Getty Images
Freelancers are in an interesting position. You are in charge of your time, and making the most of it is absolutely crucial to a successful freelancing career. Unlike office jobs with dedicated work hours, freelance work requires a great deal self-motivation and personal accountability. That being said, here are some of the most time-wasting, productivity-killing pitfalls to avoid when freelancing: Distracting Websites We all know that feeling, “I’m just going to open up Facebook for a quick second before I get to work.” Before you know it, an hour’s gone by and you’ve not gotten shit done. While taking a break to browse around the web for pleasure can be a helpful reprieve, the point is that it’s a break. The most successful freelancers know that their time is valuable, and setting aside blocks of time for dedicated work is absolutely crucial. Thankfully, even those lacking the most basic sense of self-control can force themselves to get things done with the right tools. There are a myriad of websites and apps like StayFocused or Cold Turkey are out there that block certain websites or even web browsing all together and allow you to set parameters to keep you on task. You don’t have to go nuclear here and toss out your router. Just set aside dedicated blocks of time for work and periodic breaks to keep yourself sane. Procrastination A concept familiar to everyone. From putting off your third grade math homework to waiting till the last minute to get started on that proposal, the procrastination bug is infectious and everyone can catch it. Some people tend to use the excuse, “But I work best under pressure!” This may be true for some, but more often than not you’re sacrificing the quality of the work. Give yourself enough time to complete a project well, and you minimize your chances of making a critical mistake or missing a deadline. Clutter If your desk is looking more like a warzone than a productive workspace, you’re likely suffering from some serious clutter issues. Piles of books, folders, and a jillion other work items can add up quickly, so it’s best to keep on top of things before they detract from the effectiveness of your workspace. Now, I’m not saying you need a blank canvas every time you sit down to get things done, but there’s nothing that kills a productive streak quicker than rifling through every stack of crap on your desk to find the right document. Don’t go all hyper-anal here — Drill Sergeant Hartman isn’t going to be wiping his finger across your desk looking for dust particles. Just keep a bit of a system in place; keep important things nearby, and clear away all the crap that’s distracting you from the task at hand. Unfinished Work This one really goes hand in hand with procrastination. Even a quick to-do list can explode into an all-nighter if you let your unfinished work get out of hand. There’s nothing wrong with walking away from something to switch gears and picking it back up later with a fresh set of eyes, but make sure you’re actually coming back to the task. One way to keep yourself in check on this front is to prioritize. Make a to-do list with some hierarchy: things that absolutely must be completed today sit at the very top, while projects that have some flexibility are lower priorities. This way, even when you’re switching between one project and another, you’ll always know which tasks require the most of your attention on that particular day. Living in the Stone Age You might have a particular way of going about things that simply works best for you; we all get a little set in our ways from time to time. But ignoring a technology or a service that could streamline your processes can really come back to bite you in the end. You don’t see brokers waiting for the daily newspaper to keep on top of the stock market, right? Keep informed about new technologies that pertain to your business, and don’t be afraid to try something out of your comfort zone if you think it can help your business. As a freelancer, you’re in one of the most independent fields of work out there. All of this freedom comes with a higher degree of responsibility, however, and knowing what to look out for helps you avoid them all the better.
www.about.com
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Top 10 Highly-Desired Skills You Can Teach Yourself
On countless occasions, you've likely said to yourself "I wish I knew how to
do ______." Then, of course, life got in the way and you put it off until you
could find the time. Maybe you wanted to become fluent in a language, learn a
new instrument, start performing your house repairs, or a master a myriad of
other skills. With the vast amount of knowledge online, you're now your only
excuse. Here are the top ten most highly desired skills that you can teach
yourself—and should.
10. Repair Just About Anything
Sure, you don't need to repair anything anymore. You can just pay someone
else to do it. But where's the ingenuity in that? Plus, who wants to waste a
bunch of money on simple tasks you can handle on your own? If you've adopted the
DIY spirit, learning to repair your own stuff is one of the easiest and more
rewarding skills you can acquire. It's especially fruitful because as you learn
new things, you can put them to use right away. So how do you teach yourself?
We've outlined
tons of repairs you can learn on your own to get you started, but if you're
looking for something specific there is no shortage of how-to videos available
on YouTube and VideoJug. There will be occasions when you
do need to call a professional, as you're not going to be a master repairman (or
woman) instantly, but do remember that there is an opportunity when things
break: you can learn how to fix them.
9. Pick Up an Artistic Skill Like Illustration, Painting, or Photography
Although it often won't earn you the big bucks, artistic skills are highly
desired because they provide you with the technical abilities required to create
something beautiful. You're going to have to find your own inspiration and
subject matter, but the skill you'll need is really just a matter of technical
aptitude and practice. Picking up a book of anatomy and drawing different bones
and muscles will teach you how to draw people. Drawing grids over photographs
can show you basic perspective. Obviously it isn't as simple as that, but
focusing on learning to draw one simple thing, like the petals of a flower or
the human hand, will help you learn how it works and get in a reasonable amount
of practice. When you're ready to move on from the basics and start illustrating
on your computer, check out our digital
painting lessons. For those of you interested in photography, we
have lessons for you, too.
Whatever you're looking to learn, just set aside 15-30 minutes every day to
practice a very small part of that skill. It'll take awhile to teach yourself
how to draw, paint, take better photos, make hamburger sculptures out of clay,
or whatever it is you want to do, but breaking the daunting task into pieces and
practicing each part slowly will do the trick. Plus, it's a really nice way to
unwind at the end of the day.
8. Learn to Defend Yourself
Who likes getting their ass kicked? Probably a very small majority. If that's
what you're into, it doesn't require much
skill—just endurance. If you'd prefer
to not end up hurt or injured as the result of an unexpected attack,
perhaps it's time to pick up some self-defense skills. While you'll probably
want to have a partner around to help you out—at least when you want to test
your skill—we've outlined
several self-defense moves that you can learn on your own. Although you will
hopefully never need to actually employ the techniques you acquire, if you do
you'll increase your chances of coming out of a fight unharmed. Plus, it's
pretty cool to walk around with the confidence of being able to take on most
anyone in a fight.
7. Improve Your Design Skills (or At Least Acquire a Sense of Style)
Design and style aren't an exact science, as tastes differ and change as time
goes on, but there are a few principles you can pick up that'll make your work,
home, or whatever needs an aesthetic boost looking better than average. If we're
talking traditional design, you'll first want to learn
the basics of type and layout. These are skills you can employ in your
everyday work to make it look a lot more attractive. This may seem like a
nearly-useless skill, because spreadsheets aren't getting entered in any beauty
contests, but when something looks good it can have a greater impact. That's
always a plus in your work. If you want to take things a bit further, you can
bump those skills up a notch and apply
them to web site design in Photoshop. Your sense of style is even a useful
thing when choosing a great
wallpaper and creating
a clean and organized desktop on your computer. If your home is boring, just
follow
these guidelines for awesome interior design. You don't have to be a pro,
but learning
the basics of design can make your life a lot brighter.
6. Pick Up Just About Any Subject You Missed In College
Whether it's science, finance, math, humanities, law, or anything else, if
there's a course you wish you took in college you're not out of luck—you can
probably find it online. To help you out, we've rounded
up every great source of online education so you can gain that knowledge you
missed. What's great about learning online is that you can take it at your own
pace and put in as much time as you can spare each day. You don't necessarily
have to master a subject, either, but learn as much as you need or want to know.
While you won't end up with a degree for your hard work, you will be a little
bit smarter—and that's the most important part.
5. Build and Hack Electronic Hardware
We love technology, and we love it more when we can make it do pretty much
whatever we want. There is almost no end to what
you can hack, but getting started does require teaching yourself a few
skills. Learning
to build a computer is a good place to start. Soldering
is especially helpful, and understanding
the basics of arduino can help you build some really neat stuff. One of the best ways
to get started is to pick a project and learn by doing. If you're not sure where
to start, our DIY tag page can
offer a few ideas.
4. Play a (New) Instrument
Whether you already know how to play an instrument and want to learn
something new or are musically inept, you'll find plenty of resources online to
help you teach yourself to play just about anything. If guitar is your thing,
you're in luck as you'd be hard-pressed to not find online lessons. JustinGuitar.com
offers over 500, and we've
rounded up plenty more. The internet can also teach you piano, drums, and even orchestral
instruments like the flute and violin. Just like with
repair skills, you can find a lot of how-to videos on both YouTube and VideoJug.
In addition to the instrument, you're also going to want to learn a little
music theory. Ricci Adams' musictheory.net offers a bunch
of free lessons to get you started. When you're starting to get good, you can put
together a home recording studio on the cheap to start capturing your talent
and sharing it with others.
3. Cook Like a Pro
With so many recipe sites and cooking skill how-to videos online, it's a
surprise that everyone isn't a master chef at this point. There are so many
simple things you can learn that can vastly improve your culinary skill set
really quickly, many of which we've
covered. We've written so much on the subject of learning to cook better
that this little paragraph isn't enough to cover it all, but there are a few
posts in particular that you'll want to read to get started. First, these tips
and tricks for budding foodies will make your learning process easier.
Second, follow
this station-by-station kitchen guide to stay organized and efficient when
cooking. Finally, these
must-know recipes will help you round out your arsenal of cooking knowledge.
For more, we like recipe and how-to sites Epicurious and How2Heroes. And, of course, you can always
check our how to and kitchen tag
pages for more great tips.
2. Become Fluent in a New Language
When we
asked you which skills you really wanted to learn, language was at, or close
to the top of many peoples' lists. Fortunately for you, this clever technique offers a way to
all but master a new language in a short period of time by teaching yourself.
You'll still have to work hard and put in the minutes every day, but you can
come out speaking fluently in about half of a year. Pretty cool.
1. Make a Web Site, Create an App, or Just Learn to Code
Learning to code is something most of us Lifehackers aspire to do at one
point or another, as it's not only a great way to create cool apps and tools
that we want to use but it's also an incredibly marketable skill when trying to
get a job. To get you started, we've put together two helpful sets of lessons:
the
basics of programming and making
a web site.
Both sets include further resources, but there are plenty of others that
we've learned about or have cropped up since. For starters, commenter
mistermocha suggests using the "learn ___ the hard way" series. For example,
if you wanted to learn Python, you could visit learnpythonthehardway.org. If you
just fill in the blank with the language you want to learn and put that into a
web search, you'll likely find what you're looking for. (You can also find most
of the series here.) If you prefer
more interactive lessons, you'll want to check out one of our favorites: Codecademy. I learned by subscribing to
online learning site Lynda.com (and through a few
basic classes back in college), which is still excellent, but I'd probably have
gone with Code Academy at this point since it's in the free category. Regardless
of how you decide to learn, programming skills are becoming more and more useful
as time goes on. Code is not as complicated as you think, so go get started!
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Researchers prove magnetism can control heat, sound
Fri, 05/29/2015 - 7:47am
Jamie Abel, Ohio Supercomputer Center 
A team led by Ohio State's Wolfgang Windl, PhD, used OSC's Oakley Cluster to calculate acoustic phonon movement within an indium-antimonide semiconductor under a magnetic field. Their findings show that phonon amplitude-dependent magnetic moments are induced on the atoms, which change how they vibrate and transport heat. Image: OSUPhonons—the elemental particles that transmit both heat and sound—have magnetic properties, according to a landmark study supported by Ohio Supercomputer Center (OSC) services and recently published by a researcher group from The Ohio State Univ. In Nature Materials, the researchers describe how a magnetic field, roughly the size of a medical MRI, reduced the amount of heat flowing through a semiconductor by 12%. Simulations performed at OSC then identified the reason for it—the magnetic field induces a diamagnetic response in vibrating atoms known as phonons, which changes how they transport heat. "This adds a new dimension to our understanding of acoustic waves," said Joseph Heremans, PhD, Ohio Eminent Scholar in Nanotechnology and a professor of mechanical engineering at Ohio State whose group performed the experiments. "We've shown that we can steer heat magnetically. With a strong enough magnetic field, we should be able to steer sound waves, too." People might be surprised enough to learn that heat and sound have anything to do with each other, much less that either can be controlled by magnets, Heremans acknowledged. But both are expressions of the same form of energy, quantum mechanically speaking. So any force that controls one should control the other. The nature of the effect of the magnetic field initially was not understood and subsequently was investigated through computer simulations performed on OSC's Oakley Cluster by Oscar Restrepo, PhD, a research associate, Nikolas Antolin, a doctoral student, and Wolfgang Windl, PhD, a professor, all of Ohio State's Dept. of Materials Science and Engineering. After painstakingly examining all possible magnetic responses that a non-magnetic material can have to an external field, they found that the effect is due to a diamagnetic response, which exists in all materials. This suggests then that the general effect should be present in any solid. The implication: in materials such as glass, stone, plastic—materials which are not conventionally magnetic—heat can be controlled magnetically, if you have a powerful enough magnet. This development may have future impacts on new energy production processes. But, there won't be any practical applications of this discovery any time soon: seven-tesla magnets like the one used in the study don't exist outside of hospitals and laboratories, and a semiconductor made of indium antimonide had to be chilled to -450 F (-268 C)—very close to absolute zero—to make the atoms in the material slow down enough for the phonons' movements to be detectible. To simulate the experiment, Windl and his computation team employed a quantum mechanical modeling strategy known as density functional theory (DFT). The DFT strategy was used to determine how the electron distribution changed when atoms vibrated with or without magnetic field. The motion of the electrons around their atoms changed in the field, creating diamagnetic moments when phonons were present. These moments then reacted to the field and slowed the heat transport, similar to an eddy current brake in a train. The simulations were conducted on the Oakley Cluster, an HP/Intel Xeon system with more than 8,300 processor cores to provide researchers with a peak performance of 154 Teraflops--tech-speak for 154 trillion calculations per second. Since atoms can vibrate in many different ways, a large number of simulations were necessary, consuming approximately 1.5 million CPU hours even on a machine as powerful as Oakley. OSC engineers also helped the research team use OSC's high-throughput, parallel file system to handle the immense datasets generated by the DFT model. "OSC offered us phenomenal support; they supported our compilation and parallel threading issues, helped us troubleshoot hardware issues when they arose due to code demands, and moved us to the Lustre high-performance file system after we jammed their regular file system," said Antolin, who is the expert for high-demand computations in Windl's group. "Dr. Windl and his team are important OSC clients, and we're always pleased to support their research projects with our hardware, software and staff support services," said David Hudak, PhD, OSC's director of supercomputer services. "With the addition of the Ruby Cluster this past fall and another, much more powerful system upcoming this fall, OSC will continue to offer even larger, faster and more powerful services to support this type of discovery and innovation." .
Source: Ohio Supercomputer Center
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Oral Medication & Non-Insulin Injectables
Knowing the type of medication you take, when to take it and
what it does is really important to managing your diabetes. Arming
yourself with this information can help you to manage your blood sugars
and alert you to potential side effects.Because everyone with
diabetes is so different, your prescription will take your individual
differences into consideration. This includes your blood sugars, past
medical history, age, cost, potential side effects, and the medication's
effects on weight.
Before filling any prescription, you may want to confirm with your insurance provider or health care provider if this medicine is preferred by your plan – this will help to save you money. Remember, while medications are very important, they are always considered secondary to diet and exercise. If you are new to diabetes medicines and are not sure what your medicine does or when you should take it, find out now.
9. Injectable Non-Insulin Medicines
Learn About More Oral Diabetes Medications
Before filling any prescription, you may want to confirm with your insurance provider or health care provider if this medicine is preferred by your plan – this will help to save you money. Remember, while medications are very important, they are always considered secondary to diet and exercise. If you are new to diabetes medicines and are not sure what your medicine does or when you should take it, find out now.
Table of Contents
1. Biguanides- Metformin (Fortmate®, Glucophage®, Glucophage XR®, Glumetza®, Riomet®)
- Pioglitazone (Actos®)
- Glimepiride (Amaryl®)
- Glyburide (Diabeta®, Micronase®)
- Glipizide (Glucotrol®, GlucotrolXL®)
- Repaglinide (Prandin®)
- Nateglinide (Starlix®)
- Sitagliptin (Januvia®)
- Linagliptin (Trajenta®)
- Saxagliptin (Onglyza®)
- Alogliptin (Nesina®)
- Canagliflozin (Invokana®)
- Dapagliflozin (Farxiga®)
- Empagliflozin (Jardiance®)
- Miglitol (Glyset®)
- Acarbose (Precose®)
9. Injectable Non-Insulin Medicines
Learn About More Oral Diabetes Medications
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