21 junho 2015
Rings and Seasons of Saturn
On Saturn, the rings tell you the season. On Earth, today marks a solstice, the time when the Earth's spin axis tilts directly toward the Sun. On Earth's northern hemisphere, today is the Summer Solstice, the day of maximum daylight. Since Saturn's grand rings orbit along the planet's equator, these rings appear most prominent -- from the direction of the Sun -- when the Saturn's spin axis points toward the Sun. Conversely, when Saturn's spin axis points to the side, an equinox occurs and the edge-on rings are hard to see. In the featured montage, images of Saturn over the past 11 years have been superposed to show the giant planet passing from southern summer toward northern summer. Although Saturn will only reach its northern summer solstice in 2017 May, the image of Saturn most analogous to today's Earth solstice is the bottommost one.
from NASA http://ift.tt/1ezyjdb
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Lorena Hickok. A well-known journalist that was invited by...
Lorena Hickok. A well-known journalist that was invited by Eleanor Roosevelt to live in the White House until she found a house in Washington. She stayed for four years. She was also a very good friend of Eleanor Roosevelt for the rest of her life.
Southeast Asia Before Angkor
This period is unfortunately left out of many history classes, mainly because so little is known outside of archaeological evidence and contemporary Chinese sources. So I’ve written a brief overview of what was going on in the Mekong Delta and Thai peninsula before the 700s CE.
image noise, photographed / not photographed by soho, 14th june...
image noise, photographed / not photographed by soho, 14th june 2015.
35 frames, photographed over 7.5 hours, with the subject of the images removed as much as possible; some traces of the background stars remain, however. near centre, elnath (beta tauri) is somewhat visible as a crescent. most of the noise is from charged particles hitting the image detector.
image credit: nasa/soho. animation: ageofdestruction.
agerockthatlookslikeafacerock: nowyoukno: Source for more facts...
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There is considerable controversy about where the word “Eskimo” came from, and even more about using...
There is considerable controversy about where the word “Eskimo” came from, and even more about using it. The word may be a corruption of the Cree word askamiciw, meaning “eater of raw meat,” which has always been a racial slur used by the Cree against their northern neighbors. But etymologists suspect this may, in fact, be folk theory based only on a linguistic coincidence. Some say it’s just as likely that “Eskimo” came from a word meaning “he ties snowshoes.” There is even an old theory, which is for the most part believed untrue today, that the word was invented by Jesuit missionaries, who referred to pagan Inuits as “the excommunicated ones.”
Linguistic origins aside, for the most part “Eskimo” has been used as a derogatory slur against the native Inuit and Inuk peoples. In Canada they prefer “Inuit” and in Greenland they prefer Greenlanders or Kalaallit. In Alaska, “Eskimo” is a bit more acceptable because it is inclusive of the Inuit and the Yupik, two different tribes whose languages share grammatical structure but are mutually unintelligible. In every case, you should probably ask what people prefer to be called. It’s just good manners.
The Brain That Heals Itself: Neuroplasticity and Promise for...
The Brain That Heals Itself: Neuroplasticity and Promise for Addiction Treatment
A woman sits at her piano, practicing a five-finger exercise. For two hours a day, she practices the exercise over and over, her finger movements growing sharper, more precise and fluid. Another woman sits in a chair, hands still, and imagines playing the same five-finger exercise. For two hours a day, she practices in her mind and she can visualize herself getting faster, more melodic, more purposeful. After five days, the motor cortex corresponding to these finger movements has flourished in the brain of the woman playing the piano, proving that behaviors physically alter the brain. But what is more fascinating is that these neural changes also occurred in the woman who was simply imagining playing the piano. In other words, we can change the structure of our brains simply by thinking.
The human brain has historically been a mysterious thing, a slippery and elusive being. For years it was thought that the brain completed its development early and then sat fixed, immutable, and vulnerable to damage from which it could not heal. Then an opera singer with MS regains his soaring voice. A blind man teaches himself to see. A man with Parkinson’s cures his symptoms by walking. And research begins to teach us that the brain is not static, but a flexible organ with the ability to form itself to behavior, reorganize itself to accommodate change, and compensate for damage. The brain is inventive, responsive, and, through careful modulation, full of promise.
The Changing Brain
As you think new thoughts, practice new skills, and participate in new behaviors, neural pathways form. As these thoughts and behaviors are repeated, the pathways strengthen, habits emerge, and the brain is rewired to invite the use of these roads. Like a well-worn forest trail we walk every day, we know them by feel, the memory of their twists is imprinted on us, their turns sewn into our consciousness. Meanwhile, pathways we no longer use weaken, become impassable and hostile in comparison to their more popular, open alternatives. This plastic nature of the brain – or neuroplasticity – opens up a world of potential for people to optimize their minds through improved cognitive function, memory, language skills, and guard against age-related decline. It also gives us a new way of conceptualizing addiction, and the promise of treatment possibilities to guide users to recovery using the innate resources of their own brains.
Addiction As A Brain Disorder
For years, debate has raged between schools of thought that frame addiction as a choice versus addiction as a disease. Through an understanding of the brain as an adaptable organ, we can reach a more sophisticated model, describing addiction as a reorientation of the brain that creates new neural pathways and perpetuates addictive behavior. Rather than arbitrary choice, the addict’s brain has remapped itself to make feeding addiction the most natural course of action.
When a person indulges in addictive behavior, their brain floods with dopamine. Dopamine release is not only highly rewarding, it also increases the ability to learn, and tells the brain, “Remember how this happened so you can feel this way again.” As the behavior is performed again and again, the level of dopamine release decreases, and new extremes must be reached for the same effect. Eventually, tolerance may build to such a point that the addictive behavior no longer provides pleasure at all–merely avoidance of withdrawal. But even in the face of diminished rewards, the neural pathways beg for the repetition of the behavior; the brain is now built for addiction.
The Power of Neuroplasticity
While neuroplasticity may be a culprit in the creation of addiction, it also holds the key to recovery. By harnessing the moldability of the brain and abandoning the neural connections fed by addictive behaviors, new pathways can be formed via the development of healthy behaviors and thought processes. Through carefully created treatment plans, people suffering from addiction can be released from its grip to move toward stability, insight, and self-awareness.
Meditation in particular is proven to engage the brain and expand its potential. Applying the principles of meditation to treatment addiction, Mindfulness-Based Relapse Prevention (MBRP) modulates brain activity to create new neural responses to distress and cravings. Through mindful meditation, people with addiction can learn to tolerate discomfort and stressful situations with decreased reactivity, allowing them to be in control of their actions and behave in thoughtful, deliberate ways. Even more significantly, MBRP allows addicts to experience distress without increased cravings, interrupting self-destructive impulses and replacing them with healthy coping mechanisms.
Toward Recovery
By embracing the potential of neuroplasticity and integrating neural modulation into therapeutic practice, addiction treatment programs can harness the healing powers of the brain and relieve suffering. This nuanced understanding of the brain offers hope for the millions of people suffering from addiction as we forge new paths to lasting sobriety.
Put together by Alta Mira, an addiction treatment center in Los Angeles, California.
Recalling happier memories can reverse depression MIT...
Recalling happier memories can reverse depression
MIT neuroscientists have shown that they can cure the symptoms of depression in mice by artificially reactivating happy memories that were formed before the onset of depression.
The findings, described in the June 18 issue of Nature, offer a possible explanation for the success of psychotherapies in which depression patients are encouraged to recall pleasant experiences. They also suggest new ways to treat depression by manipulating the brain cells where memories are stored. The researchers believe this kind of targeted approach could have fewer side effects than most existing antidepressant drugs, which bathe the entire brain.
“Once you identify specific sites in the memory circuit which are not functioning well, or whose boosting will bring a beneficial consequence, there is a possibility of inventing new medical technology where the improvement will be targeted to the specific part of the circuit, rather than administering a drug and letting that drug function everywhere in the brain,” says Susumu Tonegawa, the Picower Professor of Biology and Neuroscience, director of the RIKEN-MIT Center for Neural Circuit Genetics at MIT’s Picower Institute for Learning and Memory, and senior author of the paper.
Although this type of intervention is not yet possible in humans, “This type of analysis gives information as to where to target specific disorders,” Tonegawa adds.
Graduate student Steve Ramirez is the paper’s lead author.
Memory control
In 2012, Tonegawa, former MIT postdoc Xu Liu, Ramirez, and colleagues first reported that they could label and reactivate clusters of brain cells that store specific memories, which they called engrams. More recently, they showed that they could plant false memories, and that they could switch the emotional associations of a particular memory from positive to negative, and vice versa.
In their new study, the researchers sought to discover if their ability to reactivate existing memories could be exploited to treat depression.
To do this, the researchers first exposed mice to a pleasurable experience. In this case, all of the mice were male and the pleasurable experience consisted of spending time with female mice. During this time, cells in the hippocampus that encode the memory engram were labeled with a light-sensitive protein that activates the neuron in response to blue light.
After the positive memory was formed, the researchers induced depression-like symptoms in the mice by exposing them to chronic stress. These mice show symptoms that mimic those of human sufferers of depression, such as giving up easily when faced with a difficult situation and failing to take pleasure in activities that are normally enjoyable.
However, when the mice were placed in situations designed to test for those symptoms, the researchers found that they could dramatically improve the symptoms by reactivating the neurons that stored the memory of a past enjoyable experience. Those mice began to behave just like mice that had never been depressed — but only for as long as the pleasant memory stayed activated.
In another set of experiments, the researchers found that they could achieve a longer-lasting improvement by reactivating the positive memory cells for 15 minutes, twice a day, for five days, before the mice underwent the tests for depressive behavior. This time, the memories were not reactivated during the test, but the mice behaved just like mice that had never been depressed.
The researchers found that the repeated memory activation provoked formation of new brain cells in a part of the hippocampus called the dentate gyrus. This did not happen during the brief activations during the behavioral tests; instead, depressive behavior was overcome by activation of a circuit connecting engram cells located in the hippocampus, amygdala, and nucleus accumbens.
“Harnessing the brain’s power”
Interestingly, the researchers found that allowing the mice to engage in pleasurable experiences after becoming depressed did not improve their symptoms nearly as much as reactivating an old memory.
“People who suffer from depression have those positive experiences in the brain, but the brain pieces necessary to recall them are broken. What we’re doing, in mice, is bypassing that circuitry and forcing it to be jump-started,” Ramirez says. “We’re harnessing the brain’s power from within itself and forcing the activation of that positive memory, whereas if you give a natural positive memory to the person or the animal, the depression that they have prevents them from finding that experience rewarding.”
The study suggests a possible scientific explanation for why psychotherapy works for some depressed patients, Tonegawa says. “In some way this depression state suppresses the ability to recall positive experiences, and what the psychiatrist is doing is trying to override that and help them to recall those memories,” he says.
That link between the neural circuit manipulations in mice and therapies now used in humans makes the findings particularly exciting, says Tom Insel, director of the National Institute of Mental Health.
“This is a big step toward helping to understand not only the underlying circuits for a really serious illness like depression, but also the circuits that underlie treatment,” says Insel, who was not involved in the research.
The findings also offer possible new approaches to developing new types of depression treatments, the researchers say. If scientists could develop a noninvasive way to stimulate specific brain circuits, they might be able to achieve the same effects seen in this study using optogenetics. One way to accomplish this could be a more targeted form of deep-brain stimulation, which requires implantation of a brain pacemaker that sends electrical impulses to specific parts of the brain. Deep-brain stimulation is sometimes used to treat Parkinson’s disease, depression, and obsessive-compulsive disorder, among other diseases.
“The problem is that deep-brain stimulation is crude and activates a large chunk of the brain,” Ramirez says. “You could imagine in the future that if you could target deep-brain stimulation not to patches of brain but to specific sets of cells that we think are holding onto a positive memory, then it offers a new therapeutic avenue.”
Sonho dos Pés
Existe muitos sonhos estranhos, alguns com partes do corpo mais exatas, como nossos pés, quando se tem um sonho dos pés, independente se foi um sonho com cobra ou sonho de amor, tem alguns significados que dependem de como você está nesse momento da vida.
Sonhos dos Pés
Dependendo de como está sua vida, tem algumas opções de significados do sonhos dos pés, se você está crescendo na vida, significa que está bem com sua alma ! Significa que seu interior está caminhando junto com você, que vai crescer muito ainda.
Sonho dos Pés
Se sua vida está embaraçada, está passando por mudanças, em relacionamentos ou de idade, como da adolescência para a vida adulta, está começando a trabalhar ou correr atrás disso, em fim, sonhar com seus pés, significa que está prestes a percorrer um caminho longo, porém, com esforço, tudo dará certo ! Basta não desistir.
Sonho dos Pés
Caso tenha acontecido uma tragédia muito grande na sua vida, sonhar com seus pés, sonho dos pés, mostra que o culpado por essa tragédia, irá pagar muito ainda ! Não tenha raiva dessa pessoa, apenas aceite o que está acontecendo, erga a cabeça e siga em frente!!!
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- Get paid to sit on your butt and do surveys on MySurvey
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- Sell old cell phones, laptops and tablets to YouRenew.com
- Sell your services on Fiverr.com for five dollars a pop
- Buy other students’ text books at the end of the year and re-sell them
- Get paid for your photography on Fotolia or iStockPhoto
- Profit from making and uploading videos with YouTube
- Fundraise money or your goal with GoFundMe
- Sell your hair for money at BuyAndSellHair.com
Incipits are the opening words of a text of a medieval...
Incipits are the opening words of a text of a medieval manuscript or early printed book. They were often highly decorated, as you can see from this Ethiopian example. Circa 1504 - 1505, tempera on parchment. (From the J. Paul Getty Museum)
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