THE EVOLUTION OF THE HUMAN EYE


The human eye is an amazing mechanism, able to detect anywhere from a few photons to a few quadrillion, or switch focus from the screen in front of you to the distant horizon in a third of a second. How did these complex structures evolve? Joshua Harvey details the 500 million year story of the human eye.

Watch the video.URL: https://www.youtube.com/watch?v=qrKZBh8BL_U

Flexible Spinal Implant May Be Future Of Paralysis Treatment; Helps Paralyzed Rats Walk Again


Although any kind of injury is bad, spinal cord injuries (SCI) might just be the scariest. Our spines are an information superhighway for nerves and their signals, which travel to the rest of the body. Just one strong blow to the back can be enough to offset vertebrae, which can tear or push into the spinal cord tissue, and just like that a person can be left paralyzed. It’s estimated that about 12,500 people will have a SCI each year, and 41 percent of them will end up either paralyzed from the waist down or throughout. After years of research, however, Swiss scientists are finally on track to giving these people their lives of movement back, with the help of elastic electrical spinal implants.

E-Dura

Scientists at Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland have been working on spinal cord implants for quite some time now, but a major roadblock for them has been maintaining flexibility akin to the spine. Current iterations of spinal cord implants are rigid and unable to move around if, for example, you’re bending down to tie your shoe. Over the course of a few days, these implants begin to rub against spinal tissue, causing inflammation and scar tissue build up. Eventually, the body rejects the implant.

The team’s new implant is called e-Dura. It’s named after the dura mater — one layer of the protective membrane that surrounds the spinal cord and brain — under which it’s placed. By using elastic silicone and cracked gold wiring, which created a mesh-like structure, the researchers were able to give it flexibility comparable to that of the nerve tissue surrounding it. And after two months of having the implant in their spines, paralyzed rats were able to walk, run, and jump without damage or rejection.

“This is quite remarkable. Until now, the most advanced prostheses in intimate contact with the spinal cord caused quite substantial damage to tissue in just one week due to their stiffness,” Dr. Dusko Ilic, from King’s College London, told the BBC. He was not involved in the study. “The work described here is a groundbreaking achievement of technology, which could open a door to a new era in treatment of neuronal damage.”

For the study, the researchers first tested the e-Dura against a stiffer implant and surgery alone, and found it was safe for the rats’ bodies without any adverse reactions. Then they inserted the implant in the rats’ motor cortexes to determine which signals indicated an intention to move their legs, and found that the device could indeed read signals, Live Sciencereported. Finally, they tested the device again on a group of paralyzed rats, finding that they had the ability to walk again after eight weeks, albeit with the help of an external stimulator which connected to the device with wires.

The team still has a long way to go if they want to bring this technology to humans. One of the first things they need to work on is getting the device to work independently of an external stimulator, which provides the signals for movement. “Translation of experimental treatments to humans often falters because insufficient attention is given to some of the more pragmatic aspects of translational science,” Dr. Mark Bacon, scientific director of the UK charity Spinal Research who wasn’t involved in the study, told the BBC.  “The combination of electrical and chemical stimulation has been proven in principle — in animal models at least — so it is encouraging to see the application of multidisciplinary efforts to take this one step closer to safe testing in patients.”

Source: Minev I, Musienko P, Lacour S, et al. Electronic dura mater for long-term multimodal neural interfaces. Science. 2014.


Reading in and of itself has plenty of benefits for our minds: Studies have shown that reading over the course of a lifetime (or even starting to read consistently when you’re well into your 60s and 70s) can prevent mental decline. Along with keeping your mind sharp and enlarging your knowledge base, reading can expand your sense of empathy, too. A 2013 study found that when people were transported into the emotional travails of books’ characters, they grew to become more empathetic in real life.

Reading

So the act of reading is great, of course. But the way you’re reading also has an impact on your physical and mental health. In our technology-driven world, the paper book has been replaced by electronic devices — Kindles and Nooks, and even reading on your laptop or smartphone. Good old-fashioned books are no longer seen as practical.

There’s something simple and special, however, about reading a classic paper book that e-books seem to lack. Recently, I was reading before bed while I drank a cup of chamomile tea, and I found that it not only relaxed me, but I fell asleep almost immediately, I slept soundly through the entire night, and I woke up feeling refreshed. I found myself pondering events and scenes in the book, the imagery glowing in my mind in place of my typically exhausting anxieties. I’m going to believe it wasn’t a coincidence: Putting aside my phone — which, in addition to texting, has access to the cyclical, distracting spirals of Facebook, Instagram, and Snapchat — and focusing on a tale that took me outside of myself, somehow, inexplicably, helped me feel better on many levels.

Reading sharpens the mind and helps fight off dementias.

Researchers have been examining the differences between reading regular books and e-books for years. Many of the studies have shown that reading old-fashioned books has plenty of advantages over e-books, which can be gateways to other electronic distractions, all of which screw with your sleep. This is why you should ditch the screen for printed pages.

1.You’re Missing Out On Important Information

A 2014 study found that readers who used Kindles were less competent in recalling the plot and events in the book than those who used paperbacks. Researchers still aren’t quite sure why this occurs, but it might have something to do with being able to physically and visually track your progress in a real book.

“In this study, we found that paper readers did report higher on measures having to do with empathy and transportation and immersion, and narrative coherence, than iPad readers,” said Anne Mangen of Stavanger University in Norway, an author of the study, according to The Guardian. “When you read on paper you can sense with your fingers a pile of pages on the left growing, and shrinking on the right. You have the tactile sense of progress, in addition to the visual. … Perhaps this somehow aids the reader, providing more fixity and solidity to the reader’s sense of unfolding and progress of the text, and hence the story.”

Digitization of text also means it’s likely to be more fragmented, full of disturbances and links that can lead you to anywhere on the Internet. Reading on an iPad with the ability to check Facebook provides an avenue to take “breaks” way too often. And in order to retain information, you need to read in long, undisturbed chunks of time.

Using laptops or phones late at night to read doesn’t make way for restful sleep, according to studies.

2.E-Books Get In The Way Of Sleepytime

A recent study out of Harvard University found that reading an e-book before bed lessened the production of an important sleep hormone known as melatonin. As a result, people took much longer to fall asleep, experienced less deep sleep, and were more fatigued in the morning.

“The light emitted by most e-readers is shining directly into the eyes of the reader, whereas from a printed book or the original Kindle, the reader is only exposed to reflected light from the pages of the book,” Charles Czeisler, lead author of the study, told the BBC. “Sleep deficiency has been shown to increase the risk of cardiovascular disease, metabolic diseases like obesity and diabetes, and cancer. Thus, the melatonin suppression that we saw in this study among participants when they were reading from the light-emitting e-reader concerns us.”

In contrast, reading an old-fashioned book can actually help you sleep better. By taking your mind off the things that you may normally stress about before falling asleep, a book can clear your mind and also make you sleepy, easing you into a full night’s rest. In addition, soft light being reflected off the pages of a book doesn’t signal to your brain that it’s time to wake up like the glaring screen of an e-book or phone.

Putting away your electronic devices and focusing on a paper book creates singularity in focus.

3.Screens = Stress

Reading helps you de-stress faster or just as fast as listening to music, taking a walk, or having a cup of tea or coffee, according to a 2009 study. When researchers measured heart rate and muscle tension, they found that people relaxed just six minutes into reading.

But reading on a device might cancel out this effect, and may even impact your stress levels negatively. Repeated use of mobile phones or laptops late at night has beenlinked to depression, higher levels of stress, and fatigue among young adults. Constant use of technology not only disrupts our sleeping patterns and throws off our circadian rhythms, but it fosters a shorter attention span and fractured focus — online, we jump from meme to meme and link to link, checking Facebook intermittently. Social media and technological distractions also always seem to foster guilt and regret, and before we know it, three hours have passed and our brains feel like mush.

It’s hard to put my finger on what exactly draws me to paper books, and makes me avoid electronic ones. Perhaps it’s the tangible qualites: Turning the pages of a book helps me mark my progress, and underlining prose that stands out to me makes reading a very intimate occasion. It could also be the science behind it: that regular books ease our minds into sleep. But it’s likely that reading allows me to rely on a singular focus to transport me to a new world, leaving all my stresses and personal problems behind. I stop the selfish cycle of technology that centers around checking my Facebook or Instagram, or taking selfies, as I wait for my brain to get rewarded from notifications and likes. Real books allow me to step outside myself and enter someone else’s world. The modern world, after all, can be tiring.

Reading an old-fashioned paper book might seem out of style, wasteful, or impractical. But don’t underestimate the simplicity of holding a physical book in your hands, flipping through the pages, and not having anything else to shift your focus to. Commit to the classic paper book and you’ll get the full, healthier experience.

Meta-Analysis: Newer RA Drugs Raise Serum Lipids


Significance of lipid dysregulation seen with Xeljanz, Actemra remains uncertain.

  • Medpage Today

Rheumatoid arthritis (RA) patients treated with tofacitinib (Xeljanz) and tocilizumab (Actemra) have notable changes in serum lipids compared with placebo-treated patients, according to a Spanish meta-analysis.

Compared with placebo-treated patients, those who received tocilizumab were more likely to have hypercholesterolemia (odds ratio 4.64, 95% CI 2.71-7.95, P<0.001). They were also more likely to have increased levels of high-density lipoprotein (HDL) cholesterol (OR 2.25, 95% CI 1.14-4.44, P=0.020), as well as increased levels of low-density lipoprotein (LDL) cholesterol (OR 4.80, 95% CI 3.27-7.05, P<0.001).

Among patients treated with tofacitinib, either 5 mg or 10 mg twice daily, the mean percentage of increases in HDL and LDL were also higher than in the trials’ comparator groups, according to the report in the January 2015 issue of Arthritis and Rheumatology.

This effect was not observed in patients treated with tumor necrosis factor (TNF) antagonists. Limiting the study’s results was the absence of lipid data for patients treated with rituximab, abatacept, or other biologics, or for patients with spondyloarthritis (SpA).

“Whether these changes pertain to the control of inflammation or to the mechanism of action of biologic agents or tofacitinib remains undetermined,” wrote researchers led by Alejandro Souto, MD, of the University Hospital Complex at the University of Santiago de Compostela in Spain.

While the biggest cause of death in RA and SpA is cardiovascular (CV) disease, the augmented risk of CV events and death related to accelerated atherosclerosis is not explained by traditional CV risk factors alone. Recently, systemic inflammation, as reflected by high levels of C-reactive protein and an elevated erythrocyte sedimentation rate, has been identified as a new independent risk factor.

The net effect on CV risk of improving the inflammatory burden with Janus kinase inhibitors (i.e., tofacitinib) and interleukin-6 antagonists (tocilizumab) but increasing cholesterol level is an emerging concern, the authors noted. In contrast, TNF antagonists and methotrexate appear to have positive effects on the rate of CV events.

Identifying 4,527 studies, the researchers reviewed 20 eligible articles and five documents on randomized, controlled trials (RCTs) in RA. Eligible studies included 12 RCTs of TNF antagonists (infliximab, adalimumab, golimumab), seven RCTs of tofacitinib, and six RCTS of tocilizumab. The investigators’ initial objective was to assess changes in the percentage of treated RA and SpA patients with abnormal lipid values or changes in the mean percentage of increase in cholesterol and triglyceride levels.

Three RCTs of TNF inhibition reported a nonsignificant increase in the percentage of patients with hypercholesterolemia (total cholesterol >240mg/dL; OR 1.54, 95% CI 0.90-2.66, P=0.119).

A comparison across different inflammatory diseases by treatment with different biologic agents may provide important information on the link between inflammatory burden, lipid profiles, and CV events, the investigators said.

And while only tofacitinib and tocilizumab produced significant changes in the lipid profiles of RA patients, the long-term consequences of CV disease in this population need to be assessed. “Meanwhile, adequate and earlier control of disease activity and systemic inflammation may perhaps improve the risk of cardiovascular disease,” they concluded.

Episiotomy Rate Continues Steady Decline


White women still more likely to have procedure.

The use of episiotomy in the U.S. has declined substantially over the last 7 years, according to a new study.

In an analysis of more than 2 million women in more than 500 hospitals, there was a decrease of almost 32%, from 17.3% of deliveries with episiotomy in 2006 (95% CI 17.2%-17.4%) to 11.6% of deliveries in 2012 (95% CI, 11.5%-11.7%, P<0.001), reported Alexander M. Friedman, MD, of Columbia University in New York City, and colleagues.

The study also found several demographic characteristics that were significantly associated with episiotomy. White women were almost twice as likely to receive episiotomy than black women (15.7% versus 7.9%, P<0.001). Those with commercial insurance received it 17.2% of the time versus 11.2% of those with Medicaid (P<0.001). Rural location and hospital teaching rates were also associated with the frequency of episiotomy, the authors wrote in a research letter in the Journal of the American Medical Association.

The analysis included 2,261,070 women of whom 325,193 underwent episiotomy (14.4%). Information was pulled from a large insurance database, and deliveries with shoulder dystocia, fetal distress, and fetal heart rate abnormalities were excluded because they may be indications for episiotomy.

The authors found significant variation among hospitals — the 10% of hospitals that performed the procedure most frequently did so 34.1% of the time. The 10% of hospitals that performed it the least did so in only 2.5% of the cases.

“The analysis demonstrated substantial between-hospital variation in episiotomy not accounted for by demographic, obstetric, and hospital characteristics,” Friedman and colleagues wrote. “These observations suggest nonmedical factors are related to use of episiotomy.”

A decreasing use of episiotomy was documented in the 1990s, but in 2004, it was estimated that as many as a full quarter of women underwent episiotomy during delivery. Though Friedman’s group said that the ideal rate of episiotomy is unknown, in 2006 the American Congress of Obstetricians and Gynecologists recommended againstroutine episiotomy after little evidence was found to support it.

The National Quality Forum in 2008 noted that episiotomy was associated with increased risks of pain, laceration, and anal incontinence, and said that limiting its use was an important measure of quality healthcare.

The study authors noted several limitations including confounding by unmeasured medical risk factors. Also, hospitals included in the analysis might not be representative of all hospitals in the U.S. Claims data, from which the numbers were pulled, are used primarily for billing purposes, and may not be entirely accurate, they cautioned.

Who Do You Think You Are? What Your Taste In Music Says About You, According To Science


What type of music do you listen to? Why can this otherwise innocent question cause some to sweat with anxiety? It’s because deep down we know that our taste in music is not just a reflection of our musical preference, but also insight into the very essence of who we are. The French scholar Jules Combarieu described the union most eloquently when he explained that “music is the art of thinking with sound,” and no one wants other people listening in on their thoughts. Although it was long suspected that music and personality were deeply entwined, science has recently delved into the intricate relationship and shown just how significant one’s musical preference is.

records

Perhaps one of the most notable studies into the connection between musical preference and personality was conducted by Dr. Adrian North, now working at Curtin University in Australia. In a 2010 study, North surveyed 36,518 people in more than 60 countries about their preference for 104 musical styles, as well as their personality. In doing so, he found that quite a lot about both a person’s personality and their lifestyle can be inferred by their musical taste.

“People do actually define themselves through music and relate to other people through it, but we haven’t known in detail how music is connected to identity,” North explained, as reported by PsychCentral. “We have always suspected a link between music taste and personality. This is the first time that we’ve been able to look at it in real detail. No one has ever done this on this scale before.”

North’s Summary of Music and Personality

Rap/Hip-Hop: high self-esteem, outgoing, not very eco-friendly

Heavy Metal: gentle, low self-esteem, reserved, and comfortable with themselves

Indie Rock: low self-esteem, creative, lazy, headstrong

Electronic/Dance: sociable, headstrong, outgoing, creative

Classical: high self-esteem, introverted, high earners, eco-friendly

Pop: high self esteem, hard working, outgoing, low creativity, nervous

To better understand how music and personality are so deeply entwined, it may be best to figure out what leads a person to listen to a specific song or type of music in the first place. A 2007 study, “Personality and music: Can traits explain how people use music in everyday life?” explained that music was associated with three main psychological functions. These included: helping to improve performance (imagine your workouts without Spotify), helping to stimulate curiosity (imagine how thoughtful you become with a song you truly love), and helping to bring out certain emotions that the listener desires (happy songs for a party, sad songs for getting over a breakup). Also, the reason that a person listens to music — to deal with emotions or as background noise — was also linked to notable differences in personality. Dr. Tomas Chamorro-Premuzic, co-author of the study, writes that because mood is so closely related to personality it would make sense that musical preference gave insight to who a person was.

More Than Just Personality

Musical preference dictates much more than personality, however.

“I think that if we have the ability to take all factors into account — a person’s age, gender, nationality, social class, everything except their personality — we could probably predict 30 percent of their musical preference,” Chamorro-Premuzic explained to Medical Daily.

This is reflected in North’s research, which showed trends such as those who like “high art music” (opera, jazz, and classical) tended to be better educated, have higher income, and have greater access to financial resources than fans of other music genres.

Unfortunately, as with many psychology studies on personality and music, there was one caveat: participants lying.

“There is a difference between the music that people report to like and what they actually listen to,” Chamorro-Premuzic said. “That’s because people are aware that liking certain music is linked to certain values and personalities.”

Since people are already hypersensitive to the fact that their musical preference reflects their personality, it would make sense that those wishing to portray a certain image would purposely say they prefer a specific genre. However, Chamorro-Premuzic explained that although a person’s musical choices will always change, their personality, as of the ages of 15 to 20, is set. By recording personality and musical choices of volunteers in this age group, it was possible to gain an accurate idea of their personality.

Although personality played a big part in musical choice, other completely unrelated factors also dictate what a person likes to listen to. “You may watch a movie or hear a soundtrack that touches you and you may prefer that song,” said Chamorro-Premuzic, explaining how personal experiences also play a part in musical preference.

Also, despite the fears of suburban parents, listening to violent music will not make a person violent.

“There is no evidence that musical preference can change people’s personalities,” Charmorro-Premuzic said. “The only thing we know is that with certain types of music, people who listen to that music tend to be quite aggressive in the first place. Listening to this music releases their aggressive tendencies, but in the long run it makes them even more aggressive.”