Scanning electron microscope picture of a nerve ending that has been broken open to reveal the synaptic vesicles beneath the cell membrane.
Image by Tina Carvalho. The Cell: An Image Library
So last night, while bored out of my mind attempting to study for exams, I randomly thought to myself “how do cute little dogs see me”
Then I came across this awesome video, that gave me lots more information, and I felt the need to share it with everyone
The U.S. Food and Drug Administration (FDA) today allowed marketing of the DEKA Arm System, the first prosthetic arm that can perform multiple, simultaneous powered movements controlled by electrical signals from electromyogram (EMG) electrodes.
EMG electrodes detect electrical activity caused by the contraction of muscles close to where the prosthesis is attached. The electrodes send the electrical signals to a computer processor in the prosthesis that translates them to a specific movement or movements.
The EMG electrodes in the DEKA Arm System convert electrical signals into up to 10 powered movements, and it is the same shape and weight as an adult arm. In addition to the EMG electrodes, the DEKA Arm System contains a combination of mechanisms including switches, movement sensors, and force sensors that cause the prosthesis to move.
This innovative prosthesis provides a new option for people with certain kinds of arm amputations,” said Christy Foreman, director of the Office of Device Evaluation at the FDA’s Center for Devices and Radiological Health. “The DEKA Arm System may allow some people to perform more complex tasks than they can with current prostheses in a way that more closely resembles the natural motion of the arm.”
The FDA reviewed clinical information relating to the device, including a 4-site Department of Veterans Affairs study in which 36 DEKA Arm System study participants provided data on how the arm performed in common household and self-care tasks. The study found that approximately 90 percent of study participants were able to perform activities with the DEKA Arm System that they were not able to perform with their current prosthesis, such as using keys and locks, preparing food, feeding oneself, using zippers, and brushing and combing hair.
The DEKA Arm System can be configured for people with limb loss occurring at the shoulder joint, mid-upper arm, or mid-lower arm. It cannot be configured for limb loss at the elbow or wrist joint.
Data reviewed by the FDA also included testing of software and electrical and battery systems, mitigations to prevent or stop unintended movements of the arm and hand mechanisms, durability testing (such as ability to withstand exposure to common environmental factors such as dust and light rain), and impact testing.
The FDA reviewed the DEKA Arm System through its de novo classification process, a regulatory pathway for some novel low- to moderate-risk medical devices that are first-of-a-kind.
Scientists at MIT have developed a new simulation that traces 13 billion years of cosmic evolution. They start the simulation shortly after the big bang with a region of space much smaller than the universe (a mere 350 million light years across). Still, it’s big enough to follow the forces that helped create the galaxies we see today, and correctly predict the gas and metal content of those galaxies.
At first, we see dark matter clustering due to the force of gravity (first two GIFs). Then we see visible matter — blue for cool clouds of gas where galaxies form, red for more violent explosive galaxies (second two GIFs).
Super massive blackholes form, superheating the material around them, causing bright white explosions that enrich the space between galaxies with warm but sparse gas (fifth GIF).
Different elements (represented by different colors in the sixth GIF) are spread through the universe.
We arrive at a distribution of dark matter that looks similar to the one we see in our universe today (seventh GIF).
The simulation is so complex it would take two thousand years to render on a single desktop. And it’s kinda beautiful.
Image Credit: MIT and Nature Video
Anonymous said: Shut the fuck up about vaccinations. Not everyone has to have them, not everyone believes in them. Uneducated fuck.
You know, my homie and secret best friend Neil deGrasse Tyson said it best….
This isn’t an issue of belief or should even be up for discussion. It’s not a debate- like gravity or that the Earth revolves around the Sun isn’t up for debate. It’s a fact, whether or not you like it. Sorry bro.
And any ‘educated fuck’ knows that vaccines are necessary and everyone who can have them should have them.
Have a lovely day, sugar.
Actually there’s a lot of research and knowledge supporting the fact that vaccines are NOT necessary. It is simply another thing that today’s health system is super big on, just like hospital births and c-sections. And a lot of people actually have long term and short term complications from getting vaccines. Ahem.
Dang guys, you thought I didn’t check my activity log every now and then? Because I knew shit like this would pop up. And, I just finished my block exam and am feeling fiesty.
Actually you’re wrong. That ‘research’ is either completely fabricated OR grossly misinterprets the data OR uses shitty research techniques to get the data they want- all which are grossly unethical, in case you’re curious. I’ve got slides from a recent lecture on vaccines (aka why I am so fired up about this nonsense). You can check out the citations on each slide if you don’t believe me… something unsurprisingly missing from literally every anti-vaccine comment I’ve gotten and website that I have visited. Show me your sources, honey, and if you do, I will blow them out of the water because not a single one stands up to current scientific research standards.
There are however tomes and tomes of research for the safety end efficacy of vaccines. Don’t believe me? Look at a simple google scholar search.
So! Here we go!
Holy shit, it’s almost like vaccines SAVE SOCIETY MONEY. In fact, they give money back to society, along with the other programs indicated by red arrows. Which would be really weird for something that is just a healthcare fad like c-sections and hospital births.
And most people have no complications for getting vaccines, and if they do, most of them are short term. In fact, it is devilishly hard to prove an adverse effect was because of a vaccine. Why? Because it’s how we’re wired. We falsely see connections and causes where there are none (called a type 1 error; you are rejecting a true null hypothesis). People are more likely to attribute an adverse health event to a shot- even if that shot is the placebo and the numbers are just the background rate for whatever health event in the population.
And here is a graph showing the sample sizes necessary to prove that an adverse event is caused or related to a vaccine.
You know what, it was a really good lecture and I’m going to share more more relevant slides in case any one else feels like contradicting me.
These slides show the public health impact of vaccines. Note the differences between the historical peak and post-vaccine era deaths columns. Because saving literally thousands of lives is totally a conspiracy you should beware of.
And this is why herd immunity is so important! See how high it has to be for measles? Guess what we’re seeing outbreaks of thanks to anti-vaxxers? Don’t forget that one of the deadly complications of measles is SSPE.
Look how Hepatitis A infections in older adults when down after kids started getting immunized. Shocking! Could vaccines be… good for …. everyone????
Anti-vaxxers are a danger to the world and we need to stop them tbh
Vitamin D deficiency and cognitive impairment are common in older adults, but there isn’t a lot of conclusive research into whether there’s a relationship between the two.
A new study from Wake Forest Baptist Medical Center published online ahead of print this month in the Journal of the American Geriatrics Society enhances the existing literature on the subject.
“This study provides increasing evidence that suggests there is an association between low vitamin D levels and cognitive decline over time,” said lead author Valerie Wilson, M.D., assistant professor of geriatrics at Wake Forest Baptist. “Although this study cannot establish a direct cause and effect relationship, it would have a huge public health implication if vitamin D supplementation could be shown to improve cognitive performance over time because deficiency is so common in the population.”
Wilson and colleagues were interested in the association between vitamin D levels and cognitive function over time in older adults. They used data from the Health, Aging and Body composition (Health ABC) study to look at the relationship. The researchers looked at 2,777 well-functioning adults aged 70 to 79 whose cognitive function was measured at the study’s onset and again four years later. Vitamin D levels were measured at the 12-month follow-up visit.
The Health ABC study cohort consists of 3,075 Medicare-eligible, white and black, well-functioning, community-dwelling older adults who were recruited between April 1997 and June 1998 from Pittsburgh, Pa., and Memphis, Tenn.
“With just the baseline observational data, you can’t conclude that low vitamin D causes cognitive decline. When we looked four years down the road, low vitamin D was associated with worse cognitive performance on one of the two cognitive tests used,” Wilson said. “It is interesting that there is this association and ultimately the next question is whether or not supplementing vitamin D would improve cognitive function over time.”
Wilson said randomized, controlled trials are needed to determine whether vitamin D supplementation can prevent cognitive decline and definitively establish a causal relationship.
“Doctors need this information to make well-supported recommendations to their patients,” Wilson said. “Further research is also needed to evaluate whether specific cognitive domains, such as memory versus concentration, are especially sensitive to low vitamin D levels.”
For centuries, researchers have studied the brain to find exactly where mechanisms for producing and interpreting language reside. Theories abound on how humans acquire new languages and how our developing brains learn to process languages.
By predicting our eye movements, our brain creates a stable world for us. Researchers used to think that those predictions had so much influence that they could cause us to make errors in estimating the position of objects. Neuroscientists at Radboud University have shown this to be incorrect. The Journal of Neuroscience published their findings – which challenge fundamental knowledge regarding coordination between brain and eyes – on 15 April.
You continually move your eyes all day long, yet your perception of the world remains stable. That is because the brain processes predictions about your eye movements while you look around. Without these predictions, the image would shoot back and forth constantly.
Errors of estimation
People sometimes make mistakes in estimating the positions of objects – missing the ball completely during a game of tennis, for example. Predictions on eye movements were long held responsible for such localization errors: if the prediction does not correspond to the eventual eye movement, a mismatch between what you expect to see and what you actually see could be the result. Jeroen Atsma, a PhD candidate at the Donders Institute of Radboud University, wanted to know how that worked. ‘If localization errors really are caused by predictions, you would also expect those errors to occur if an eye movement, which has already been predicted in your brain, fails to take place at the very last moment.’ Atsma investigated this by means of an ingenious experiment.
Localizing flashes of light
Atsma asked test subjects to look at a computer screen where a single small ball appeared at various positions at random. The subjects followed the balls with their eyes while an eye-tracker registered their eye movements. The experiment ended with one last ball on the screen, followed by a short flash of light near that ball. The person had to look at the last, stationary ball while using the computer mouse to indicate the position of the flash of light. However, in some cases, a signal was sent around the time the last ball appeared, indicating that the subject was NOT allowed to look at the ball. In other words, the eye movement was cancelled at the last moment. The person being tested still had to indicate where the flash was visible.
Even when test subjects heard at very short notice that they should not look at the ball – in other words when the brain had already predicted the eye movement – they did not make any mistakes in localizing the flash of light. ‘That demonstrates you don’t make localization errors solely on the basis of predictions’, Atsma explained. ‘So far, literature has pretty much suggested the exact opposite. That is why we repeated the experiment several times to be sure.’
The findings of the neuroscientists in Nijmegen are remarkable because they challenge much of the existing knowledge about eye-brain coordination. Atsma: ‘This has been an issue ever since we started studying how the eyes function. For the first time ever our experiment offered the opportunity to research brain predictions when the actual eye movement is aborted. Therefore I expect our publication to lead to some lively discussions among fellow researchers.’
New research reveals that brain damage affecting the insula – an area with a key role in emotions – disrupts errors of thinking linked to gambling addiction.
The research, led by Dr Luke Clark from the University of Cambridge, was published on April 7 2014 in the journal PNAS.
During gambling games, people often misperceive their chances of winning due to a number of errors of thinking called cognitive distortions. For example, ‘near-misses’ seem to encourage further play, even though they are no different from any other loss. In a random sequence like tossing a coin, a run of one event (heads) makes people think the other outcome (tails) is due next; this is known as the ‘gambler’s fallacy’.
There is increasing evidence that problem gamblers are particularly prone to these erroneous beliefs. In this study, the researchers examined the neurological basis of these beliefs in patients with injuries to different parts of the brain.
“While neuroimaging studies can tell us a great deal about the brain’s response to complex events, it’s only by studying patients with brain injury that we can see if a brain region is actually needed to perform a given task,” said Dr Clark.
For the study, the researchers gave patients with injuries to specific parts of the brain (the ventromedial prefrontal cortex, the amygdala, or the insula) two different gambling tasks: a slot machine game that delivered wins and ‘near-misses’ (like a cherry one position from the jackpot line), and a roulette game involving red or black predictions, to elicit the gambler’s fallacy. For the control groups, they also had patients with injuries to other parts of the brain as well as healthy participants undergo the gambling tasks.
All of the groups with the exception of the patients with insula damage reported a heightened motivation to play following near-misses in the slot machine game, and also fell prey to the gambler’s fallacy in the roulette game.
Clark added: “Based on these results, we believe that the insula could be hyperactive in problem gamblers, making them more susceptible to these errors of thinking. Future treatments for gambling addiction could seek to reduce this hyperactivity, either by drugs or by psychological techniques like mindfulness therapies.”
Gambling is a widespread activity: 73% of people in the UK report some gambling involvement in the past year* and around 50% play games other than the National Lottery. For a small proportion of players (around 1-5%), their gambling becomes excessive, resulting in features seen in addiction. Problem gambling is associated with both debt and family difficulties as well as other mental health problems like depression.