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. The purpose of this review article is to summarize recent researches focusing on phantom limb in order to discuss its definition, mechanisms, and treatments.

The incidence of phantom limb pain has varied from 2% in earlier records to higher rates today. Initially, patients were less likely to mention pain symptoms than today which is a potential explanation for the discrepancy in incidence rates. However, Sherman et al.4 discuss that only 17% phantom limb complaints were initiated treated by physicians. Consequently, it is important to determine what constitutes phantom pain in order to provide efficacious care. Phantom pain is pain sensation to a limb, organ or other tissue after amputation and/or nerve injury.5 In podiatry, the predominant cause of phantom limb pain is after limb amputation due to diseased state presenting with an unsalvageable limb. Postoperative pain sensations from stump neuroma pain, prosthesis, fibrosis, and residual local tissue inflammation can be similar to phantom limb pain (PLP). Patients with PLP complain of various sensations including burning, stinging, aching, and piercing pain with changing warmth and cold sensation to the amputated area which waxes and wanes.6 Onset of symptoms may be elicited by environmental, emotional, or physical changes.

The human body encompasses various neurologic mechanisms allowing reception, transport, recognition, and response to numerous stimuli. Pain, temperature, crude touch, and pressure sensory information are carried to the central nervous system via the anterolateral system, with pain & temperature information transfer via lateral spinothalamic tracts to the parietal lobe. In detail, pain sensation from the lower extremity is transported from a peripheral receptor to a first degree pseudounipolar neurons in the dorsal root ganglion and decussate and ascend to the third-degree neurons within the thalamus.7 This sensory information will finally arrive at the primary sensory cortex in the postcentral gyrus of the parietal lobe which houses the sensory homunculus.8 It is unsurprising that with an amputation that such an intricate highway of information transport to and from the periphery may have the potential for problematic neurologic developments.

In 1928, Santiago Ramón y Cajal, the father of modern neuroscience, proclaimed that the brains of adult humans never make new neurons. “Once development was ended,” he wrote, “the founts of growth and regeneration ... dried up irrevocably. In the adult centers the nerve paths are something fixed, ended and immutable. Everything must die, nothing may be regenerated.”

For decades, scientists believed that neurogenesis—the creation of new neurons—whirs along nicely in the brains of embryos and infants, but grinds to a halt by adulthood. But from the 1980s onward, this dogma started to falter. Researchers showed that neurogenesis does occur in the brains of various adult animals, and eventually found signs of newly formed neurons in the adult human brain.

Finally, Gage and others say that several other lines of evidence suggest that adult neurogenesis in humans is real. For example, in 1998, he and his colleagues studied the brains of five cancer patients who had been injected with BrdU—a chemical that gets incorporated into newly created DNA. They found traces of this substance in the hippocampus, which they took as a sign that the cells there are dividing and creating new neurons.

Situated around 2,400 miles from the nearest continent, the Hawaiian Islands are about as remote as it’s possible for islands to be. In the last 5 million years, they’ve been repeatedly colonized by far-traveling animals, which then diversified into dozens of new species. Honeycreeper birds, fruit flies, carnivorous caterpillars ... all of these creatures reached Hawaii, and evolved into wondrous arrays of unique forms.

The most spectacular of these spider dynasties, Gillespie says, are the stick spiders. They’re so-named because some of them have long, distended abdomens that make them look like twigs. “You only see them at night, walking around the understory very slowly,” Gillespie says. “They’re kind of like sloths.” Murderous sloths, though: Their sluggish movements allow them to sneak up on other spiders and kill them.

Gillespie has shown that the gold spiders on Oahu belong to a different species from those on Kauai or Molokai. In fact, they’re more closely related to their brown and white neighbors from Oahu. Time and again, these spiders have arrived on new islands and evolved into new species—but always in one of three basic ways. A gold spider arrives on Oahu, and diversified into gold, brown, and white species. Another gold spider hops across to Maui and again diversified into gold, brown, and white species. “They repeatedly evolve the same forms,” says Gillespie.

Unfortunately, however, little is known about the wiring of the brain. This is due also to a problem of time: tracking down connections in collected data would require man-hours amounting to many lifetimes, as no computer has been able to identify the neural cell contacts reliably enough up to now. Scientists from the Max Planck Institute of Neurobiology in Martinsried plan to change this with the help of artificial intelligence.

To be able to use this key, the connectome, that is every single neuron in the brain with its thousands of contacts and partner cells, must be mapped. Only a few years ago, the prospect of achieving this seemed unattainable.

The Max Planck scientists led by Jörgen Kornfeld have now overcome this obstacle with the help of artificial neural networks. These algorithms can learn from examples and experience and make generalizations based on this knowledge.

When was the last time you disinfected your phone? According to a 2017 study, high levels of bacterial contamination can be found on the surface of cell phones.

Time magazine suggests that your phone could be 10 times dirtier than your toilet seat.

Frequently looking down at your phone for extended periods of time puts a strain on your neck

Ethicists and physicians are concerned that, amid a desire to put an end to the Covid-19 pandemic, developers of drugs and vaccines have become overly enthusiastic about the chances their products will work.

Oxford has recently walked back some of its optimism, but for months, it set a tone that its vaccine was the most promising, without any solid evidence that this was based in fact.

Third, one leader in the Oxford team has gone so far as to denigrate other teams trying to get a Covid vaccine on the market, calling their technology "weird" and labeling it as merely "noise." Such name-calling is highly unusual and aggressive among scientists.

Healthy adults built up Alzheimer’s-associated proteins in their cerebral spinal fluid when prevented from getting slow-wave sleep, the deepest stage of sleep, researchers report July 10 in Brain. Just one night of deep-sleep disruption was enough to increase the amount of amyloid-beta, a protein that clumps into brain cell‒killing plaques in people with Alzheimer’s. People in the study who slept poorly for a week also had more of a protein called tau in their spinal fluid than they did when well rested. Tau snarls itself into tangles inside brain cells of people with the disease.

In stark contrast to earlier findings, adults do not produce new nerve cells in a brain area important to memory and navigation, scientists conclude after scrutinizing 54 human brains spanning the age spectrum.

Nerve cells in the brain make elaborate connections and exchange lightning-quick messages that captivate scientists. But these cells also sport simpler, hairlike protrusions called cilia. Long overlooked, the little stubs may actually have big jobs in the brain.

Ripped musclesThe metabolism is every drop of chemistry needed to keep the body going. And the bigger the body - whether that is ripped muscles or too much belly fat - the more energy it will take to run.

The study, published in the journal Science, found four phases of metabolic life:birth to age one, when the metabolism shifts from being the same as the mother's to a lifetime high 50% above that of adults a gentle slowdown until the age of 20, with no spike during all the changes of pubertyno change at all between the ages of 20 and 60a permanent decline, with yearly falls that, by 90, leave metabolism 26% lower than in mid-life

Other surprises came from what the study did not find. There was no metabolic surge during either puberty or pregnancy and no slowdown around the menopause.

"This type of stuff probably happens all the time. What's unusual here is that someone checked it," says Ray Panko, a professor at the University of Hawaii and the elder statesman of small coterie of research academics who study—yes—Excel errors. Panko's meta-analysis of several such studies, he claims, indicates that 84 percent of spreadsheets contain some kind of materially significant error.

There are ample anecdotes to support Panko and Powell's claims

 In 2012, JP Morgan discovered that it had been grossly miscalculating a risk-management measure—possibly for years—due to a mischievous Excel formula.

Every living thing is a pulse. We quicken, then we fade. There is a deep beauty in this, but deeper down, inside every plant, every leaf, inside every living thing (us included) sits a secret.

Everything alive will eventually die, we know that, but now we can read the pattern and see death coming. We have recently learned its logic, which "You can put into mathematics," says physicist Geoffrey West. It shows up with "extraordinary regularity," not just in plants, but in all animals, from slugs to giraffes. Death, it seems, is intimately related to size.

Life is short for small creatures, longer in big ones.

If you take a look at the progress of science, the sciences are kind of a continuum, but they're broken up into fields. The greatest progress is in the sciences that study the simplest systems. So take, say physics -- greatest progress there. But one of the reasons is that the physicists have an advantage that no other branch of sciences has. If something gets too complicated, they hand it to someone else.

If a molecule is too big, you give it to the chemists. The chemists, for them, if the molecule is too big or the system gets too big, you give it to the biologists. And if it gets too big for them, they give it to the psychologists, and finally it ends up in the hands of the literary critic, and so on.

neuroscience for the last couple hundred years has been on the wrong track. There's a fairly recent book by a very good cognitive neuroscientist, Randy Gallistel and King, arguing -- in my view, plausibly -- that neuroscience developed kind of enthralled to associationism and related views of the way humans and animals work. And as a result they've been looking for things that have the properties of associationist psychology.

In 2008, Nate Silver correctly predicted the results of all 35 Senate races and the presidential results in 49 out of 50 states. Since then, his website, fivethirtyeight.com (now central to The New York Times’s political coverage), has become an essential source of rigorous, objective analysis of voter surveys to predict the Electoral College outcome of presidential campaigns. 

Political junkies, activists, strategists, and journalists will gain a deeper and more sobering sense of Silver’s methods in The Signal and the Noise: Why So Many Predictions Fail—But Some Don’t (Penguin Press). A brilliant analysis of forecasting in finance, geology, politics, sports, weather, and other domains, Silver’s book is also an original fusion of cognitive psychology and modern statistical theory.

Its most important message is that the first step toward improving our predictions is learning how to live with uncertainty.

occasionally lured by the promises of effortless slimming

Dr.-Oz-endorsed Garcinia Cambogia pills are languishing in his kitchen cupboard - because they don’t seem to work. Bruni applauds the recent interest in fighting aggressively marketed junk-that-makes-us-fat, and wants to remind us that we should also pay attention to aggressively marketed pills

most of the supplements marketed as fat burners have little or no science to support their claims

You feel happiness all the way down to your genes, scientists say. But the kind of happiness you're feeling matters, as different kinds can have wildly different effects on your physical well-being.

he happiness you get from instant gratification -- eating that giant cupcake or buying that fabulous pair of shoes -- may have the same physical impact on your genes as depression or stress,

The experts divide well-being into two different types: hedonic and eudaimonic. These are fancy words to describe happiness that comes from two different sources.

ringleader of the Paris attacks last month appears to have directed the three terrorists inside the Bataclan theater by phone from a few blocks away,

Abdelhamid Abaaoud standing in a doorway yelling into his phone for about an hour.

Abaaoud's head was shaved and he was wearing layers of loose clothing, but when photographs were later published in the media the witness immediately recognized him and alerted the authorities.

In people it is called episodic memory, and it involves a sense of self. In animals, it’s called episodic-like memory, because it’s difficult to try to plumb something as elusive as self without the aid of language.

Dr. Fugazza and colleagues reported online in Current Biology that this showed that the dogs remembered an event they hadn’t been concentrating on, the trainer’s action. She said one aspect strengthened that conclusion: The dogs tended to lie down immediately when they got back to the mat, suggesting that their heads were in “lie down” mode, not “do it” mode.

He said human episodic memory is lost in Alzheimer’s disease and he and others study animal memory in hopes of learning how to combat that loss. The work on dogs offers a new technique that could be very useful, he said.

A new study on killer whales, published on Thursday in Current Biology, suggests reproductive conflict between mothers and daughters may have played an important role in the evolution of menopause.

Yet they can live to be more than 90, meaning they might spend up to two-thirds of their lives not birthing any offspring.

But the unique demography of killer whale social groups may motivate younger females to invest more competitive effort into reproduction