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Feeling anxious Your mood may actually change how your dinner tastes, making the bitter and salty flavors recede, according to new research. This link between the chemical balance in your brain and your sense of taste could one day help doctors to treat depression. There are currently no on-the-spot tests for deciding which medication will work best in individual patients with this condition. Researchers hope that a test based on flavor detection could help doctors to get more prescriptions right first time. It has long been known that people who are depressed have lower-than-usual levels of the brain chemicals serotonin or noradrenaline, or in some cases both. Many also have a blunted sense of taste, which is presumably caused by changes in brain chemistry. To unpick the relationship between the two, Lucy Donaldson and her colleagues at the University of Bristol, UK, gave 20 healthy volunteers two antidepressant drugs, and checked their sensitivity to different tastes. The drug that raised serotonin levels made people more sensitive to sweet and bitter tastes, the team reports in the Journal of Neuroscience. The other, which increased noradrenaline, enhanced recognition of bitter and sour tastes. In healthy people, volunteers whose anxiety levels were naturally higher were less sensitive to bitter and salty tastes. "What hasn’t been done beore is to look precisely at which tastes are affected in depression," says Donaldson. Now the results are in, "we can discriminate between the chemicals and the tastes that seem to be altered," she says. Testing sensitivity to sweet and sour tastes could potentially help doctors to pick up on which chemicals are dipping, guiding them when choosing which drug to rectify the problem. Currently, doctors rely on physical and emotional symptoms to make a best guess at an individual’s imbalance, prescribe a drug and wait about a month to check on any improvement. Good doctors have about a 60-80% success rate in selecting the right drug the first time, says psychiatrist Jan Melichar, a co-author on the paper. Are there any decent tests for prescribing drugs for depression "No. We do a best guesstimate," says Melichar. "I’m excited by this finding because in 3, 5 or 7 years we could have a simple taste test. " Next, the team plans to perform similar tests in depressed people, and in healthy volunteers given another brain chemical called tryptophan. This chemical would lower the healthy subjects’ levels of serotonin, as actually happens in depressed patients. The work has also generated interest from flavor houses--companies that develop chemicals for the food and drink industry--who are interested in making foods taste just as sweet with half the amount of sugar. "Theoretically there would be the possibility of enhancing your meal with drugs that affect brain chemicals so that things would taste better--you couid have a ’designer taste tablet’," Donaldson says. The word "blunted" (Line 2, Paragraph 2) most probably means ______.

A. sharp
B. painful
C. insensitive
D. sweet

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It has been almost half a decade since Norman Mailer described leas Vegas in his novel The American Dream. But it (1) to be one of the most (2) and exhilarating (使人愉快的) holiday destinations in the world. An end-less (3) of colorful sights and activities are surrounded by skyscrapers and the magnificent Nevada desert. With (4) shopping, luxury spas, five-star dining and some of the most extravagant entertainment, you will (5) see, this is a city (6) offers an experience like no other. Perhaps the enduring appeal of this " (7) capital of the world", though, is that it always has something (8) to offer. Recently the Hard Rock Café has been (9) up its act, completing with a new 42 000 sq ft venue, 1 000-seater cinema and an "interactive rock wall"-allowing customers the chance to (10) images of Hard Rock’s collection. City Center is an $ 8.5 billion (£5.3 billion) complex on the Strip; a place that, in a city already (11) with extraordinary casinos (娱乐场) and hotels, stands out from the (12) It was the largest privately (13) construction project in the US and has three stand-alone hotels, a sprawling shopping and entertainment district and two 37-storey glass towers of (14) flats, designed by the likes of Norman Foster. Another Las Vegas (15) , Planet Hollywood, has (16) with luxury developers to create Westgate Towers--where you could own a piece of the action and a chance to come back to Las Vegas every year. (17) , the only thing you’ll (18) of in Vegas is not knowing which club, restaurant or spa to choose from. But then you can always ask a(n) (19) or the concierge--the fantastic thing about this city is that its residents (20) it as much as you will.

A. title
B. sample
C. staple
D. theme

输入动物经检疫不合格的,由口岸动植物检疫机关签发《检疫处理不合格通知单》。()

A. 对
B. 错

阅读以下HFC宽带接入Internet的技术说明,根据要求回答问题1~6。 [说明] 某小区采用HFC接入Internet的解决方案进行网络设计,网络结构如图2-27所示。 [问题1] 请为图2-27拓扑结构中,(1)~(5)空缺处选择对应的设备名称。 备选设备为:CMTS、以太网交换机、光收发器、光电转换节点、Cable Modem。

There are many innovations turning up in the latest experimental and production electric cars, affecting everything from batteries to motors to control systems. The need to make them all work together is prompting a complete rethink about the way cars should be designed and manufactured, and it is unclear which technologies will dominate as the constraints imposed by internal combustion engines give way to the new limits and possibilities associated with electric propulsion. (46) But one group of engineers have stuck their necks out and declared that a particular technology, the electric hub motor, is likely to become the most widely used drive system.At this week’s Deutsche Messe technology show in Hanover, researchers at the Fraunhofer Institute displayed an electric vehicle which they are using as a test platform to investigate new vehicle systems. (47) It includes electric hub motors, which they have developed to be markedly more powerful than any such motors currently available. The motors have all the necessary power and control systems integrated into the wheel hub, greatly reducing the number of connections between the hub motors and the rest of the vehicle.(48) Because hub motors can deliver power independently to each wheel, tricks like four-wheel-drive are possible, and with software monitoring each wheel, stability and traction control can also be built-in. Besides dispensing with the traditional engine bay on a car, hub motors save space and weight because there is no need for a mechanical transmission, with its driveshafts and differential units.(49) Some critics of the technology think having heavy electric motors in the wheels of cars will have a negative effect on vehicle handling. But Hermann Pleteit, a project manager with one of the 33 Fraunhofer research centres that have teamed up to work on the experimental car, says the chassis and many other parts of the vehicle can be configured in such a way to compensate for this.Several carmakers and component suppliers are interested in hub motors. Michelin, for one, is developing a system it calls the Active Wheel. (50) As well as an electric motor to drive the wheel, it contains a second electric motor to operate an active suspension system that is also built into the wheel hub. Michelin reckons this arrangement, which is now being tested in cars, could make other conventional parts, like shock absorbers, unnecessary. But one group of engineers have stuck their necks out and declared that a particular technology, the electric hub motor, is likely to become the most widely used drive system.

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