Parkinsons' drug helps older people to make decisions

Mar. 24, 2013 ? A drug widely used to treat Parkinson's Disease can help to reverse age-related impairments in decision making in some older people, a study from researchers at the Wellcome Trust Centre for Neuroimaging has shown.

The study, published today in the journal Nature Neuroscience, also describes changes in the patterns of brain activity of adults in their seventies that help to explain why they are worse at making decisions than younger people.

Poorer decision-making is a natural part of the aging process that stems from a decline in our brains' ability to learn from our experiences. Part of the decision-making process involves learning to predict the likelihood of getting a reward from the choices that we make.

An area of the brain called the nucleus accumbens is responsible for interpreting the difference between the reward that we're expecting to get from a decision and the reward that is actually received. These so called 'prediction errors', reported by a brain chemical called dopamine, help us to learn from our actions and modify our behaviour to make better choices the next time.

Dr Rumana Chowdhury, who led the study at the Wellcome Trust Centre for Neuroimaging at UCL, said: "We know that dopamine decline is part of the normal aging process so we wanted to see whether it had any effect on reward-based decision making. We found that when we treated older people who were particularly bad at making decisions with a drug that increases dopamine in the brain, their ability to learn from rewards improved to a level comparable to somebody in their twenties and enabled them to make better decisions."

The team used a combination of behavioural testing and brain imaging techniques, to investigate the decision-making process in 32 healthy volunteers aged in their early seventies compared with 22 volunteers in their mid-twenties. Older participants were tested on and off L-DOPA, a drug that increases levels of dopamine in the brain. L-DOPA, more commonly known as Levodopa, is widely used in the clinic to treat Parkinson's.

The participants were asked to complete a behavioural learning task called the two-arm bandit, which mimics the decisions that gamblers make while playing slot machines. Players were shown two images and had to choose the one that they thought would give them the biggest reward. Their performance before and after drug treatment was assessed by the amount of money they won in the task.

"The older volunteers who were less able to predict the likelihood of a reward from their decisions, and so performed worst in the task, showed a significant improvement following drug treatment," Dr Chowdhury explains.

The team then looked at brain activity in the participants as they played the game using functional Magnetic Resonance Imaging (fMRI), and measured connections between areas of the brain that are involved in reward prediction using a technique called Diffusor Tensor Imaging (DTI).

The findings reveal that the older adults who performed best in the gambling game before drug treatment had greater integrity of their dopamine pathways. Older adults who performed poorly before drug treatment were not able to adequately signal reward expectation in the brain -- this was corrected by L-DOPA and their performance improved on the drug.

Dr John Williams, Head of Neuroscience and Mental Health at the Wellcome Trust, said: "This careful investigation into the subtle cognitive changes that take place as we age offers important insights into what may happen at both a functional and anatomical level in older people who have problems with making decisions. That the team were able to reverse these changes by manipulating dopamine levels offers the hope of therapeutic approaches that could allow older people to function more effectively in the wider community."

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The above story is reprinted from materials provided by Wellcome Trust, via EurekAlert!, a service of AAAS.

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Journal Reference:

1. Rumana Chowdhury, Marc Guitart-Masip, Christian Lambert, Peter Dayan, Quentin Huys, Emrah D?zel, Raymond J Dolan. Dopamine restores reward prediction errors in old age. Nature Neuroscience, 2013; DOI: 10.1038/nn.3364

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/~3/Xj13SPpXrwY/130324152308.htm

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Sorting Chinese International Shopping Sites by Business Model

Chinese international shopping websites can be sorted by whether they sell products or offer services. The former is the traditional business model and is more widely adopted by Chinese merchants while the latter is getting more and more popular these years.

Type 1: Sites = Suppliers

Sites offering products to customers with their own warehouses are the most common in terms of quantity. Such sites have their own product sourcing teams, product management teams, pre-sales teams and after-sales teams and marketing teams and handle orders by their internal staff instead of manufacturers or suppliers cooperated with them.

Generally, this type of stores focuses on a rather limited number of product categories. For instance, some mainly sell fashion and accessories, some offer electronics while some others may be famous for toys, home and garden supplies, car parts and accessories, lighting supplies, luggage and bags, jewelry and watches or any other field(s). These professional stores may also carry some minor categories other than their major ones. For instance, as a store well-known for women?s fashion, Lightinthebox.com also sells a variety of electronic gadgets like tablet PCs & accessories, cell phones & accessories or car electronics. Here is a short list of the most popular Chinese online shops that fall into this type:

At the same time, there are a small number of Chinese shopping malls that cover a broad range of categories. Anyway, the really strong ones of this type are very rare in the Chinese cross-border trade arena. So far I personally only know Dinodirect.com is doing a good job in this area. The site have several warehouses around the world and the major one is based in Shenzhen, China. Let?s just take a look at what they are offering: men?s clothing, women?s clothing, tablet PCs, Android phones, flashlights, handheld game consoles, OBD2 & diagnostic tools, iPhone accessories, baby, cameras & camcorders, car & motorcycle accessories, computers & networking, cool gadgets, security & surveillance, electronics, gifts & holiday supplies, health & beauty, home & garden, jewelry & watches, novelties, office supplies, sporting goods, toys & hobbies, video games and books.

Type 2: Sites = Service Providers

The other type of Chinese e-commerce websites offer service for sellers and buyers and do not sell products themselves. These sites can be categorized into two sub-categories: one offers information service and the other offers transaction service. Anyway, they have one thing in common: they are not responsible for quality check, shipping, exchanging, returning or any other product-related services. These sites make money from charging membership fees or transaction-based commissions. Usually, they only charge money on sellers while some may also require buyers to pay membership fees, especially for some VIP membership programs.

1) Sites = Information/Directory Service Providers

The information service providing sites list products and/or suppliers so that buyers can search the products or suppliers they are looking for. Typical examples are Alibaba.com and Globalsources.com. Generally, such sites serve big wholesalers and buyers. That is, their major business target is wholesale trading in big volume. The majority of products listed there require a MOQ (minimum order quantity) of 100 pieces per order/item or more.

2) Sites = Transaction Service Providers

The transaction service providers are quite different. Unlike the information service providers, their target customers are small and medium-sized businesses. They usually do not charge fees on common members but reduce money from the payment made for each single order by a certain percentage. They call it ?commission?. That is, sellers can post or showcase products and create stores there for free, but once they have made a successful deal, they need to share the margin with the site as a return for their service. In addition to providing website space and shopping system, these sites also offer payment protection service. When a buyer and a seller reach an agreement on a transaction, the buyer sends the payment to the account of the site first. Then, after the site confirm that the item has been signed by the buyer and no dispute is occurred, they release the payment to the seller. When a dispute happens, the site would hold the money until the problem is solved. When you choose to trade with Chinese sellers at this type of sites, you need to read their service agreements carefully first. In particular, you should make clear how their dispute system works in case you encounter an unhappy shopping experience there. Also, it is important to keep all relevant evidence in order to win your support from the site?s ruling.

Generally, the China-based wholesale trading sites that offer transaction service are more likely to be complaint against or rated negatively by customers. When you are aware of how they run their business, you may find this phenomenon happens only naturally. You know, the sellers doing business at such sites vary significantly in certifications and service standards and their products can be very different in terms of quality levels. Many unhappy buyers throw all their anger at the site instead of the specific sellers as a result these sites have lots of bad reviews online. Just try searching by terms like ?Aliexpress scam?, ?DHgate complaints?, ?Tradetang scammer? or ?madeinchina rip offs? in Google. You will get tons of related results. I guess this can well prove what I am saying here is true.

From my personal perspective, buyers have good reasons to blame the transaction websites like Aliexpress as it is their responsibility to select premium suppliers and allow them to do business there. Likewise, these sites should be strict enough to crash down on those lower-quality sellers or products in order to create a better shopping environment. If their sellers are often complaint against, the sites deserve the bad names, don?t you think so?

The most famous Chinese wholesale trading platforms are as follows:

In particular, the first two sites listed above are much more powerful and thus better known to the world.

To find out Chinese store that offer the categories you are interested in, you can visit our page of China Online Stores, where the most popular names are listed neatly by category.

Source: http://www.danviews.com/sorting-chinese-international-shopping-sites-by-business-model/

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Knox must wait 1 more day for Italy court decision

ROME (AP) ? Italy's highest court delayed until Tuesday a decision on whether American student Amanda Knox will face a new trial in the murder of her British roommate ? an unusual but not unprecedented move.

The court heard six hours of arguments Monday and spent several hours deliberating that and a handful of other cases before announcing it would issue a decision at 10 a.m. (0900 GMT) Tuesday on whether the 2011 acquittals of Knox and her Italian ex-boyfriend Raffaele Sollecito will stand.

Italian prosecutors have asked the high court to throw out the acquittals of Knox and Sollecito in the murder of 21-year-old British student Meredith Kercher and order a new trial.

The high court normally issues the decisions the same day it hears arguments. But prosecutor general Luigi Riello told reporters that "in very complex cases, it happens" that the court takes another day.

Lawyers for Sollecito declined to speculate on what the delay could mean for the decision. Sollecito's father was calm about the development.

"We have waited so many years, one night is not going to make a difference," Francesco Sollecito said outside the courthouse. He said he hadn't spoken to his son, who did not attend the hearing, about the day's proceedings.

Knox, meanwhile, was waiting anxiously in Seattle to hear if her long legal battle is over.

"She's carefully paying attention to what will come out," attorney Luciano Ghirga said as he arrived at Italy's Court of Cassation in Rome. "This is a fundamental stage. The trial is very complex."

Knox, now 25, and Raffaele Sollecito, who turns 29 on Tuesday, were arrested in 2007, shortly after Kercher's body was found in a pool of blood in her bedroom in the rented apartment she shared with the American and others in the university town of Perugia, where they were exchange students. Her throat had been slashed.

Prosecutors alleged that Kercher was the victim of a drug-fueled sexual assault.

Knox and Sollecito have both maintained their innocence, although they said that smoking marijuana the night Kercher was killed had clouded their recollections.

Knox and Sollecito were convicted and given long prison sentences: 26 years for Knox, 25 for Sollecito. But an appeals court acquitted them in 2011, criticizing virtually the entire case mounted by prosecutors. The appellate court noted that the murder weapon was never found, said that DNA tests were faulty and added that Knox and Sollecito had no motive to kill Kercher.

After nearly four years behind bars in Italy, Knox returned to her hometown of Seattle and Sollecito resumed his computer science studies. Knox is now a student at the University of Washington, according to her family spokesman, Dave Marriott.

In the second and final level of appeal, prosecutors are now seeking to overturn the acquittals, while defense attorneys say they should stand.

The court can decide to confirm the acquittal, making it final, or throw out the Perugia appellate court ruling entirely or partially, remanding the case to a new appeals court trial.

In that case, Italian law cannot compel Knox to return to Italy. The Italian appellate court hearing the case could declare her in contempt of court but that carries no additional penalties.

It is unclear what would happen if she was convicted in a new appeals trial.

"If the court orders another trial, if she is convicted at that trial and if the conviction is upheld by the highest court, then Italy could seek her extradition," Knox's lawyer Carlo Dalla Vedova said.

Italy is not obliged to seek her extradition but it could decide to do so. Then it would be up to the United States to decide if it honors the request. U.S. and Italian authorities could also come to a deal that would keep Knox in the United States.

Riello, the prosecutor general, argued before the court that there were ample reasons "not to bring down the curtain on the case."

Riello said the appellate court was too dismissive in casting aside DNA evidence that led to the conviction in the lower court, arguing that another trial could make way for more definitive testing.

Defense attorneys said they were confident the acquittals would be upheld.

"We know Raffaele Sollecito is innocent," said his attorney, Giulia Bongiorno, who called the entire case "an absurd judicial process."

Before the court, Bongiorno argued there was an "unending series of errors by scientific police" in how they handled evidence in the case, including the fact that the crime scene had been disturbed "and possibly contaminated" during the investigation.

A young man from Ivory Coast, Rudy Guede, was convicted of the slaying in a separate proceeding and is serving a 16-year sentence. Kercher's family has resisted theories that Guede acted alone.

The lawyer for the Kercher family, Francesco Maresca, said the family was likely to issue a statement when the decision is announced. They did not attend the arguments.

The court is also hearing Knox's appeal against a slander conviction for having accused a local pub owner of carrying out the killing. The man was held for two weeks based on her allegations, but was then released for lack of evidence.

Riello argued that conviction should stand because "you cannot drag in an innocent person while exercising your right to a defense."

Knox's lawyer Dalla Vedova said the slander verdict should be thrown out because Knox had not been advised that she was a suspect during the questioning.

"The girl was confused, worn out" after 14 hours of questioning by police that stretched overnight, Dalla Vedova said, adding that while Knox was alone, 36 investigators signed the interrogation sheet.

___

Associated Press writer Chris Grygiel contributed from Seattle.

Source: http://news.yahoo.com/knox-must-wait-1-more-day-italy-court-210655782.html

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Ableton Push review: a dedicated controller for the Live faithful

MIDI might be a little long in the tooth as protocols go, but it's been the prevailing standard for getting music hardware and software to play nice pretty much since its inception. As such, the MIDI controller is a fairly established staple in professional and bedroom studios alike. The problem is they're generic by nature. They come in all shapes and sizes, but to be profitable, they need to appeal to a broad range of applications. Ableton clearly didn't think this arrangement was up to snuff, though, so it created Push -- a software controller built entirely for its popular Live production software. While there have been Live-specific controllers before -- some even officially endorsed by Ableton -- Push is a whole new beast. It's one that hopes to unite hardware and software in a way that an all-purpose controller never could.

Ableton also has lofty musical ambitions for Push: it claims it designed the hardware as an instrument in and of itself; something that lets you close the lid of the laptop and use to make music with, while not looking like you are checking your email. And, given that Ableton makes the software that it's building Push for, integration is understandably expected to be airtight. But how well does it work? Is it an instrument? Will it replace all your other controllers? Do you want one? Is it worth the $599 pre-order price? Will it blend? We've pushed ourselves to explore the device fully in an effort to find out (apart from that last question, of course).

Gallery: Ableton Push review

Filed under: Misc, Peripherals

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Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/81iOzNKTZ3s/

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Speed Article Writing ? What You Need To Know | Social Media ...

By alberttorressmt | March 23, 2013

The majority of people do not have any concept about what is feasible with article writing, and we really are speaking about the range of effects.

Article marketing is one of the best ways to get targeted visitors to your websites. Many gurus use this tactic even today, simply because it is one of the most viable traffic generating tools any Internet marketer can use. It is about volume, getting as many articles out there as you can on a regular basis. Your success online is based upon the consistency of your marketing strategy, and this is true for article marketing as well. Regardless of how many websites that you have to promote, the more content you have out there, the more traffic you will see. The following article talks about three important tips to help you write articles fast so that you?re able to produce a high number of articles in a short amount of time ?.

Learn the basic structures of different kinds of essays, or articles, and that will be a firm foundation. You want people to finish reading what you write, and that is why your writing has to be organized in a clear fashion.

The outline serves to keep your ideas organized and your writing smoothly flowing.

If you are not in the habit of researching for everything you write, unless you know the topic very well, then you have to change that. In other words, your creativity will kick in much better when you have the facts laid out and the research has been effectively completed. We hope it is obvious that your article writing speed will pick up and that is what you want. Spending some time to get the facts right will not only help you with one article, but it will help you over and over again when you write about the same topic in the future.

We do hope what you?ve reading through in this post concerning article writing, and likewise additionally the info?? regarding online business, is? useful for your requirements. Please continue reading?? more to receive added ideas regarding this subject.

Let?s talk about making sure your articles are top quality, and that involves going back over them later on after you are done with them. So, what does this have to do with cranking out high quality articles at breakneck speeds? It?s simple, when you know that you don?t have to go through the proof reading process after each article, you won?t break the flow that you?ve achieved and this will automatically allow you to produce better articles much quicker. Ideally, you want your ability to write to become very good, and that will be made possible when you do all this, yourself. If you desire to learn how to write a lot of articles each day and with excellent quality, then learn a solid method for article speed writing. Obviously quality is always an important element, but when you combine it with quantity, the results that you can get are nothing short of amazing. It is nice to hope and dream about things, but you know very well that is not enough. Time to get up and then begin tackling your next set of articles.

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Darden Restaurants Earnings Call Nuggets: Industry Trends Outlook ...

Darden Restaurants (NYSE:DRI) recently reported its third quarter earnings and discussed the following topics in its earnings conference call.

Industry Trends Outlook

David Tarantino ? Robert W. Baird & Company: My question is related to the trends you are seeing in March. Drew, I think you mentioned that the industry trends have started to improve in March. I was just wondering, if you can maybe talk about your business and maybe give us a sense of the magnitude of the improvement that you?ve seen and whether you are currently running in line with what you?ve planned for the current quarter?

Clarence Otis Jr. ? Chairman and CEO: David, this is Clarence, and we will talk about the industry, but not about our business, which is our practice. What we would say, and I think Malcolm Knapp was on Bloomberg yesterday. So, this is comments that he made, and he is (out) for a lot of reasons has a very good look at what?s going on in the industry. The turn in March has been significant. I mean February was a month that was down mid-single digits in the casual dining part of the industry and March is a positive month. So, a pretty significant turn. We think February suffered beyond weather, from really, as Drew mentioned, the consumer just weren?t prepared despite all the conversation for the payroll tax increase and there was a pretty rapid spike up in gasoline prices, but March indicates that consumers have adjusted. When we talked about our expectations for the year from a same-restaurant perspective, from an earnings perspective, we assume that the industry would bounce back.

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David Tarantino ? Robert W. Baird & Company: I guess just maybe a quick follow-up on that. As you look at the overall consumer environment, it has been choppy lately and I guess how are you viewing the March trend? Is this consistent with what your economic models and your thoughts on the overall consumer environment should be going forward? How should ??

C. Bradford Richmond ? SVP and CFO: Yeah, I think we look beyond the month and so as we look back over to last 12 months, our point of view is the next 12 is not going to be all that different. So GDP growth is roughly 2%, a little bit less than that. It?s going to be roughly 2% going forward is how we think about it, maybe slightly more than that, but there?s probably equal probabilities on slightly more slightly less and so that?s sort of how we?re planning the business around that point of view.

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Ancient volcanoes drove half of all species to extinction, study suggests

A new study indicates that massive volcanic activity and the resultant climate change some 200 million years ago?were behind the widespread extinction of land and sea species that made way for the rise of dinosaurs.?

By Tanya Lewis,?LiveScience / March 21, 2013

In Clifton, New Jersey, a massive lava flow (black rock on left) from the time of the End Triassic is exposed in a former quarry. Reddish sedimentary rocks signaling the extinction itself lie to the far right.

Paul Olsen/Lamont-Doherty Earth Observatory

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Massive volcanic eruptions may have led to the extermination of half of Earth's species some 200 million years ago, a new study suggests.

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The release of gases from giant eruptions caused climate change that led to the End-Triassic Extinction, the widespread loss of land and sea species that made way for the rise of the dinosaurs, the research says. The new study, published today (March 21) in the journal Science, shows that a set of major eruptions spanning from what is now New Jersey to Morocco occurred very close to the time of the extinction.

Scientists suspected previously that such volcanic activity and the resultant climate change were responsible for this major extinction and at least four others. But researchers weren't able to constrain the dates of the eruptions and extinctions well enough to prove the hypothesis. The new study, however, dates the End-Triassic Extinction to 201.56 million years ago, the same time the volcanoes were blowing their tops.

The eruptions, known as the Central Atlantic Magmatic Province, began when the land on Earth was part of one giant supercontinent called Pangaea. They lasted more than 600,000 years and created a rift that became the Atlantic Ocean. The researchers studied lava from these flows in modern-day Nova Scotia, Morocco and New Jersey. [Big Blasts: History's 10 Most Destructive Volcanoes]

The previous dates for these eruptions had error margins of 1 million to 3 million years, but this study decreases those numbers by an order of magnitude, lead author Terrence Blackburn, a geologist at the Carnegie Institution for Science, told LiveScience.

The results showed that the oldest massive eruptions were in Morocco, followed by the ones in Nova Scotia 3,000 years later and then those in New Jersey another 10,000 years after that. Animal and plant fossils, along with pollen and spores from the Triassic era, can be found in sediment layers underneath the lava flows, but not in layers above them. This suggests the eruptions wiped out those species. The organisms that went extinct include eel-like fish called conodonts, early crocodile species, tree lizards and broad-leaved plants.

The evidence heats up

Blackburn and colleagues determined the age of the lavas based on their mineral content. When lava flows cool, the center regions remain hot, and some chemical elements, like the mineral zircon, fail to crystallize. Zircon incorporates large amounts of uranium, which radioactively decays into lead at a specific rate. By measuring the ratio of uranium to lead in lava rock, the scientists could figure out precisely when the eruptions occurred.

"Zircon's really the perfect time capsule,"Blackburn said.

A second piece of evidence supporting the role of volcanism comes from reversals in the Earth's magnetic field. The researchers found mineral grains from one of these reversals in the sediment layer that formed just before the extinction. Since the researchers found the same layers at every site they studied, the magnetic reversal serves as a marker for when the extinction occurred.

A final line of evidence comes from repetitive motions of the Earth. As the planet rotates on its axis, it wobbles around like a top, which causes the amount of energy it receives from the sun to fluctuate depending on the areas that are pointed directly at the sun. These fluctuations correspond to different climate conditions and occur on a regular interval. By using these intervals, the researchers were able to determine the age of fossil-containing sediments to within 20,000 years.

Warming the planet

The gigantic eruptions would have vented sulfates that reflected sunlight back into space, effectively cooling the planet for several thousand years. But the eruptions would also have released large amounts of carbon dioxide and other greenhouse gases, causing global warming. Many species wouldn't have been able to survive this dramatic shift in temperature and would have died out.

The findings are "a nice confirmation of what we and others have been aware of for some time," geologist Paul Renne of the Berkeley Geochronology Center in California, who was not involved in the study, told LiveScience. "The main difference is the dating that they used is more precise than our results were."

Follow Tanya Lewis on Twitter?and Google+.?Follow us @livescience, Facebook?& Google+. Original article on LiveScience.com.

Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Source: http://rss.csmonitor.com/~r/feeds/science/~3/BUpNEpJxEuE/Ancient-volcanoes-drove-half-of-all-species-to-extinction-study-suggests

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