Statistics of the occupation time for a class of Gaussian Markov processes
ted演讲稿我们为什么要睡眠英文
ted演讲稿我们为什么要睡眠英文a(“content_1”);a(“content_2”);欢迎来到聘才网，以下是聘才小编为大家搜索整理的，欢迎大家阅读。
ted演讲稿我们为什么要睡眠英文简介：一生中，我们有三分之一的时间都在睡眠中度过。
关于睡眠，你又了解多少?睡眠专家Russell Foster为我们解答为什么要睡觉，以及睡眠对健康的影响。
What I'd like to do today is talk about one of my favorite subjects, and that is the neuroscience of sleep. Now, there is a sound -- (Alarm clock) -- aah, it worked -- a sound that is desperately, desperately familiar to most of us, and of course it's the sound of the alarm clock. And what that truly ghastly, awful sound does is stop the single most important behavioral experience that we have, and that's sleep. If you're an average sort of person,36 percent of your life will be spent asleep, which means that if you live to 90, then 32 years will have been spent entirely asleep.Now what that 32 years is telling us is that sleep at some level is important. And yet, for most of us, we don't give sleep a second thought. We throw it away. We really just don't think about sleep. And so what I'd like to do today is change your views, change your ideas and your thoughts about sleep. And the journey that I want to take you on, we need to start by going back in time.Enjoy the honey-heavy dew of slumber. Any ideas who said that? Shakespeare's Julius Caesar. Yes, let me give you a few more quotes. O sleep, O gentle sleep, nature's soft nurse, how have I frighted thee? Shakespeare again, from -- I won't say it -- the Scottish play. [Correction: Henry IV, Part 2] (Laughter) From the same time: Sleep is the golden chain that ties health and our bodies together. Extremely prophetic, by Thomas Dekker, another Elizabethan dramatist.But if we jump forward 400 years, the tone about sleep changes somewhat. This is from Thomas Edison, from the beginning of the 20th century. Sleep is a criminal waste oftime and a heritage from our cave days. Bang. (Laughter) And if we also jump into the 1980s, some of you may remember that Margaret Thatcher was reported to have said, Sleep is for wimps. And of course the infamous -- what was his name? -- the infamous Gordon Gekko from Wall Street said, Money never sleeps.What do we do in the 20th century about sleep? Well, of course, we use Thomas Edison's light bulb to invade the night, and we occupied the dark, and in the process of this occupation, we've treated sleep as an illness, almost. We've treated it as an enemy. At most now, I suppose, we tolerate the need for sleep, and at worst perhaps many of us think of sleep as an illness that needs some so rt of a cure. And our ignorance about sleep is really quite profound.Why is it? Why do we abandon sleep in our thoughts? Well, it's because you don't do anything much while you're asleep, it seems. You don't eat. You don't drink. And you don't have sex. Well, most of us anyway. And so therefore it's -- Sorry. It's a complete waste of time, right? Wrong. Actually, sleep is an incredibly important part of our biology, and neuroscientistsare beginning to explain why it's so very important. So let's move to the brain.Now, here we have a brain. This is donated by a social scientist, and they said they didn't know what it was, or indeed how to use it, so -- (Laughter) Sorry. So I borrowed it. I don't think they noticed. Okay. (Laughter)The point I'm trying to make is that when you're asleep, this thing doesn't shut down. In fact, some areas of the brain are actually more active during the sleep state than during the wake state. The other thing that's really important about sleep is that it doesn't arise from a single structure within the brain, but is to some extent a network property, and if we flip the brain on its back -- I love this little bit of spinal cord here -- this bit here is the hypothalamus, and right under there is a whole raft of interesting structures, not least the biological clock. The biological clock tells us when it's good to be up, when it's good to be asleep, and what that structure does is interact with a whole raft of other areas within the hypothalamus, the lateral hypothalamus, the ventrolateral preoptic nuclei. All of those combine, and they sendprojections down to the brain stem here. The brain stem then projects forward and bathes the cortex, this wonderfully wrinkly bit over here, with neurotransmitters that keep us awake and essentially provide us with our consciousness. So sleep arises from a whole raft of different interactions within the brain, and essentially, sleep is turned on and off as a result of a range ofOkay. So where have we got to? We've said that sleep is complicated and it takes 32 years of our life. But what I haven't explained is what sleep is about. So why do we sleep? And it won't surprise any of you that, of course, the scientists, we don't have a consensus. There are dozens of different ideas about why we sleep, and I'm going to outline three of those.The first is sort of the restoration idea, and it's somewhat intuitive. Essentially, all the stuff we've burned up during the day, we restore, we replace, we rebuild during the night. And indeed, as an explanation, it goes back to Aristotle, so that's, what, 2,300 years ago. It's gone in and out of fashion. It's fashionable at the moment because what's been shown is that within the brain, a whole raft of genes have been shown to be turned ononly during sleep, and those genes are associated with restoration and metabolic pathways. So there's good evidence for the whole restoration hypothesis.What about energy conservation? Again, perhaps intuitive. You essentially sleep to save calories. Now, when you do the sums, though, it doesn't really pan out. If you compare an individual who has slept at night, or stayed awake and hasn't moved very much, the energy saving of sleeping is about 110 calories a night. Now, that's the equivalent of a hot dog bun. Now, I would say that a hot dog bun is kind of a meager return for such a complicated and demanding behavior as sleep. So I'm less convinced by the energy conservation idea.But the third idea I'm quite attracted to, which is brain processing and memory consolidation. What we know is that, if after you've tried to learn a task, and you sleep-deprive individuals, the ability to learn that task is smashed. It's really hugely attenuated. So sleep and memory consolidation is also very important. However, it's not just the laying down of memory and recalling it. What's turned out to be really exciting is that our ability to come up with novel solutions to complex problemsis hugely enhanced by a night of sleep. In fact, it's been estimated to give us a threefold advantage. Sleeping at night enhances our creativity. And what seems to be going on is that, in the brain, those neural connections that are important, those synaptic connections that are important, are linked and strengthened, while those that are less important tend to fade away and be less important.Okay. So we've had three explanations for why we might sleep, and I think the important thing to realize is that the details will vary, and it's probable we sleep for multiple different reasons. But sleep is not an indulgence. It's not some sort of thing that we can take on board rather casually. I think that sleep was once likened to an upgrade from economy to business class, you know, the equiavlent of. It's not even an upgrade from economy to first class. The critical thing to realize is that if you don't sleep, you don't fly. Essentially, you never get there, and what's extraordinary about much of our society these days is that we are desperately sleep-deprived. So let's now look at sleep deprivation. Huge sectors of society are sleep-deprived, and let's look at our sleep-o-meter. So in the 1950s, good data suggests that mostof us were getting around about eight hours of sleep a night. Nowadays, we sleep one and a half to two hours less every night, so we're in the six-and-a-half-hours-every-night league. For teenagers, it's worse, much worse. They need nine hours for full brain performance, and many of them, on a school night, are only getting five hours of sleep. It's simply not enough. If we think about other sectors of society, the aged, if you are aged, then your ability to sleep in a single block is somewhat disrupted, and many sleep, again, less than five hours a night. Shift work. Shift work is extraordinary, perhaps 20 percent of the working population, and the body clock does not shift to the demands of working at night. It's locked onto the same light-dark cycle as the rest of us. So when the poor old shift worker is going home to try and sleep during the day, desperately tired, the body clock is saying, Wake up. This is the time to be awake. So the quality of sleep that you get as a night shift worker is usually very poor, again in that sort of five-hour region. And then, of course, tens of millions of people suffer from jet lag. So who here has jet lag? Well, my goodness gracious. Well, thank you very much indeed for not falling asleep, because that's what your brain is craving.One of the things that the brain does is indulge in micro-sleeps, this involuntary falling asleep, and you have essentially no control over it. Now, micro-sleeps can be sort of somewhat embarrassing, but they can also be deadly. It's been estimated that 31 percent of drivers will fall asleep at the wheel at least once in their life, and in the U.S., the statistics are pretty good: 100,000 accidents on the freeway have been associated with tiredness, loss of vigilance, and falling asleep. A hundred thousand a year. It's extraordinary. At another level of terror, we dip into the tragic accidents at Chernobyl and indeed the space shuttle Challenger, which was so tragically lost. And in the investigations that followed those disasters, poor judgment as a result of extended shift work and loss of vigilance and tiredness was attributed to a big chunk of those disasters.So when you're tired, and you lack sleep, you have poor memory, you have poor creativity, you have increased impulsiveness, and you have overall poor judgment. But my friends, it's so much worse than that.(Laughter)If you are a tired brain, the brain is craving things to wake it up. So drugs, stimulants. Caffeine represents the stimulantof choice across much of the Western world. Much of the day is fueled by caffeine, and if you're a really naughty tired brain, nicotine. And of course, you're fueling the waking state with these stimulants, and then of course it gets to 11 o'clock at night, and the brain says to itself, Ah, well actually, I need to be asleep fairly shortly. What do we do about that when I'm feeling completely wired? Well, of course, you then resort to alcohol. Now alcohol, short-term, you know, once or twice, to use to mildly sedate you, can be very useful. It can actually ease the sleep transition. But what you must be so aware of is that alcohol doesn't provide sleep, a biological mimic for sleep. It sedates you. So it actually harms some of the neural proccessing that's going on during memory consolidation and memory recall. So it's a short-term acute measure, but for goodness sake, don't become addicted to alcohol as a way of getting to sleep every night. Another connection between loss of sleep is weight gain. If you sleep around about five hours or less every night, then you have a 50 percent likelihood of being obese. What's the connection here? Well, sleep loss seems to give rise to the release of the hormone ghrelin, the hunger hormone.Ghrelin is released. It gets to the brain. The brain says, I need carbohydrates, and what it does is seek out carbohydrates and particularly sugars. So there's a link between tiredness and the metabolic predisposition for weight gain.Stress. Tired people are massively stressed. And one of the things of stress, of course, is loss of memory, which is what I sort of just then had a little lapse of. But stress is so much more. So if you're acutely stressed, not a great problem, but it's sustained stress associated with sleep loss that's the problem. So sustained stress leads to suppressed immunity, and so tired people tend to have higher rates of overall infection, and there's some very good studies showing that shift workers, for example, have higher rates of cancer. Increased levels of stress throw glucose into the circulation. Glucose becomes a dominant part of the vasculature and essentially you become glucose intolerant. Therefore, diabetes 2. Stress increases cardiovascular disease as a result of raising blood pressure. So there's a whole raft of things associated with sleep loss that are more than just a mildly impaired brain, which is where I think most people think that sleep loss resides.So at this point in the talk, this is a nice time to think, well, do you think on the whole I'm getting enough sleep? So a quick show of hands. Who feels that they're getting enough sleep here? Oh. Well, that's pretty impressive. Good. We'll talk more about that later, about what are your tips.So most of us, of course, ask the question, Well, how do I know whether I'm getting enough sleep? Well, it's not rocket science. If you need an alarm clock to get you out of bed in the morning, if you are taking a long time to get up, if you need lots of stimulants, if you're grumpy, if you're irritable, if you're told by your work colleagues that you're looking tired and irritable, chances are you are sleep-deprived. Listen to them. Listen to yourself.What do you do? Well -- and this is slightly offensive -- sleep for dummies: Make your bedroom a haven for sleep. The first critical thing is make it as dark as you possibly can, and also make it slightly cool. Very important. Actually, reduce your amount of light exposure at least half an hour before you go to bed. Light increases levels of alertness and will delay sleep. What's the last thing that most of usdo before we go to bed? We stand in a massively lit bathroom looking into the mirror cleaning our teeth. It's the worst thing we can possibly do before we went to sleep. Turn off those mobile phones. Turn off those computers. Turn off all of those things that are also going to excite the brain. Try not to drink caffeine too late in the day, ideally not after lunch. Now, we've set about reducing light exposure before you go to bed, but light exposure in the morning is very good at setting the biological clock to the light-dark cycle. So seek out morning light. Basically, listen to yourself. Wind down. Do those sorts of things that you know are going to ease you off into the honey-heavy dew of slumber.Okay. That's some facts. What about some myths?T eenagers are lazy. No. Poor things. They have a biological predisposition to go to bed late and get up late, so give them a break.We need eight hours of sleep a night. That's an average. Some people need more. Some people need less. And what you need to do is listen to your body. Do you need that much or do you need more? Simple as that.Old people need less sleep. Not true. The sleep demands ofthe aged do not go down. Essentially, sleep fragments and becomes less robust, but sleep requirements do not go down. And the fourth myth is, early to bed, early to rise makes a man healthy, wealthy and wise. Well that's wrong at so many different levels. (Laughter) There is no, no evidence that getting up early and going to bed early gives you more wealth at all. There's no difference in socioeconomic status. In my experience, the only difference between morning people and evening people is that those people that get up in the morning early are just horribly smug. (Laughter) (Applause)Okay. So for the last part, the last few minutes, what I want to do is change gears and talk about some really new, breaking areas of neuroscience, which is the association between mental health, mental illness and sleep disruption. We've known for 130 years that in severe mental illness, there is always, always sleep disruption, but it's been largely ignored. In the 1970s, when people started to think about this again, they said, Yes, well, of course you have sleep disruption in schizophrenia because they're on anti-psychotics. It's the anti-psychotics causing the sleep problems, ignoring the fact that for a hundred yearspreviously, sleep disruption had been reported before anti-psychotics.So what's going on? Lots of groups, several groups are studying conditions like depression, schizophrenia and bipolar, and what's going on in terms of sleep disruption. We have a big study which we published last year on schizophrenia, and the data were quite extraordinary. In those individuals with schizophrenia, much of the time, they were awake during the night phase and then they were asleep during the day. Other groups showed no 24-hour patterns whatsoever. Their sleep was absolutely smashed. And some had no ability to regulate their sleep by the light-dark cycle. They were getting up later and later and later and later each night. It was smashed.So what's going on? And the really exciting news is that mental illness and sleep are not simply associated but they are physically linked within the brain. The neural networks that predispose you to normal sleep, give you normal sleep, and those that give you normal mental health are overlapping. And what's the evidence for that? Well, genes that have been shown to be very important in the generation of normal sleep, when mutated, when changed,also predispose individuals to mental health problems. And last year, we published a study which showed that a gene that's been linked to schizophrenia, which, when mutated, also smashes the sleep. So we have evidence of a genuine mechanistic overlap between these two important systems.Other work flowed from these studies. The first was that sleep disruption actually precedes certain types of mental illness, and we've shown that in those young individuals who are at high risk of developing bipolar disorder, they already have a sleep abnormality prior to any clinical diagnosis of bipolar. The other bit of data was that sleep disruption may actually exacerbate, make worse the mental illness state. My colleague Dan Freeman has used a range of agents which have stabilized sleep and reduced levels of paranoia in those individuals by 50 percent.So what have we got? We've got, in these connections, some really exciting things. In terms of the neuroscience, by understanding the neuroscience of these two systems, we're really beginning to understand how both sleep and mental illness are generated and regulated within the brain. The second area is that if we can use sleep and sleepdisruption as an early warning signal, then we have the chance of going in. If we know that these individuals are vulnerable, early intervention then becomes possible. And the third, which I think is the most exciting, is that we can think of the sleep centers within the brain as a new therapeutic target. Stabilize sleep in those individuals who are vulnerable, we can certainly make them healthier, but also alleviate some of the appalling symptoms of mental illness.So let me just finish. What I started by saying is take sleep seriously. Our attitudes toward sleep are so very different from a pre-industrial age, when we were almost wrapped in a duvet. We used to understand intuitively the importance of sleep. And this isn't some sort of crystal-waving nonsense. This is a pragmatic response to good health. If you have good sleep, it increases your concentration, attention, decision-making, creativity, social skills, health. If you get sleep, it reduces your mood changes, your stress, your levels of anger, your impulsivity, and your tendency to drink and take drugs. And we finished by saying that an understanding of the neuroscience of sleep is really informing the way we think about some of the causes of mental illness, and indeedis providing us new ways to treat these incredibly debilitating conditions.Jim Butcher, the fantasy writer, said, Sleep is God. Go worship. And I can only recommend that you do the same. Thank you for your attention.(Applause)。
新视野大学英语5原文+翻译(编辑完美版)
Enhanced understanding of the genetic basis of learning is also likely to invade the classroom. It may be possible to determine which youngsters are likely to advance quickly and which ones seem doomed to "difficult" school experiences. Some authorities will insist that these findings be applied in specific cases, while others will vigorously object to any decisions made on the basis of genetic information. Drugs that claim to improve learning, memory, or enthusiasm will become readily available. Teachers and parents may face moral dilemmas that would in earlier times have been restricted to science fiction.
人的一生要从事多少种工作-
人的一生要从事多少种工作?Do Americans really go through careers like they do cars or refrigerators?As workers take in the latest round of monthly unemployment data over Labor Day weekend, Americans are focused on volatility in the job market. Much of what they hear points to growing job instability and increased autonomy of workers. Among the most-repeated claims is that the average U.S. worker will have many careers -- seven is the most widely cited number -- in his or her lifetime.Jobs researchers say the basis of the number is a mystery. 'Seven careers per person sounds utterly implausible to me,' says Ann Stevens, professor and chair of the economics department at the University of California, Davis.Yet the estimate has had extraordinary staying power. One reason is that no one knows for sure the true average number of careers. The U.S. Bureau of Labor Statistics, the Labor Department's data arm, doesn't track lifetime careers. Even so, the figure is erroneously attributed to BLS so often that the agency includes a corrective memo on its website, explaining that 'no consensus has emerged on what constitutes a career change.'What researchers do know is that job changes are common early in a person's working years: Three in four workers age 16 to 19, and half between 20 and 24, have been with their current employers for under a year, the BLS says.But early, frequent switches, which can include jumps by students between summer jobs, aren't what many people would consider career changes in the same way as a midlife switch after a decade or two in the same job. The latter type can entail major costs in retraining and pay cuts -- plus, in the current job climate, the risk of not finding employment. It is difficult to imagine, researchers say, that the typical worker undertakes a major switch seven times.Surveys of workers could be easily skewed by a small number of zealous career changers. Adding to the confusion, economists say, is that workers sometimes take on enough new responsibilities to meet a technical definition of a career change without leaving their general field.The BLS offers on its website the example of an economist who is promoted to an administrative position, changing her job function even if her title remains economist.'The problem is career change is tricky to define,' says Solomon Polachek, a professor of economics and political science at Binghamton University in New York, who nonetheless calls the seven-career figure 'a considerable overestimate.'And without hard data, anecdotal reports that point to an expanding career-change mentality in the U.S. have taken on a life of their own. The notion of continual career switches is repeated in particular by career-management experts, whose jobs involve spending a lot of time with occupation switchers. 'Based on my experience, I believe the typical person has six to seven careers, and the number is growing,' says Jeff Neil, a New York City career counselor, in an email.He describes one 30-year-old client, currently working as a manager of a doctor's office, who is exploring a new professional path. Previously, she worked in real-estate sales, at a talent agency, a sports-car dealership and as a sales representative at top-end health clubs. Mr. Neil adds that while multiple shifts are more the norm than the exception, he couldn't say for certain without formally researching the issue.While data on career changes are scarce, economists and statisticians have examined how often Americans shift jobs. The U.S. Census Bureau asks some respondents to its Current Population Survey who are employed how long they have been 'working continuously' for their current employer.These surveys have been used by researchers at the Bureau of Labor Statistics and elsewhere to count the total number of jobs in a lifetime. Their findings suggest that job stability hasn't changed all that much in the U.S. since the late 1990s. For example, the typical American worker's tenure with his or her current employer was 3.8 years in 1996, 3.5 years in 2000 and 4.1 years in 2008, the latest available data.BLS economist Chuck Pierret has been conducting a study to better assess U.S. workers' job stability over time, interviewing 10,000 individuals, first surveyed in 1979, when group members were between 14 and 22 years old. So far, members of the group have held 10.8 jobs, on average, between ages 18 and 42, using the latest data available.Dr. Pierret points out that these workers' experience might not apply to entrants to today's job market. The bureau is just starting to track job changes for people born between 1980 and 1984. But in yet another exampleof the difficulty of measuring career stability, the recent recession may have skewed things so much that long-term trends will be masked.'Enough of their working lives have been affected by the downturn,' Dr. Pierret says of the 20-somethings in the study, 'that it may be not so comparable.'美国人真的像换汽车和冰箱一样地频繁换工作吗？美国最新月度就业报告在劳工节前夕出台，上班族们尽可利用节日长周末细细审视其中的失业数据，职场的变幻莫测受到了他们的关注。
高中英语新人教版选择性必修第一册Unit2一词一句(共74个)
高中英语选必一Unit2一词一句1.phrase[中文意思]短语[英文释义]a small group of words standing together as a conceptual unit, typically forming a component of a clause.2.persuade[中文意思]说服[英文释义]cause (someone) to do something through reasoning or argument.3.switch[中文意思]开关[英文释义]a device for making and breaking the connection in an electric circuit.4.switch off/on[中文意思]关闭/打开（开关）[英文释义]to turn off or on by using a switch.5.distant[中文意思]遥远的[英文释义]far away in space or time.6.secure[中文意思]安全的[英文释义]fixed or fastened so as not to give way, become loose, or be lost.7.knob[中文意思]旋钮[英文释义]a rounded handle, as on a drawer or door.8.appliance[中文意思]家用电器[英文释义]a device or piece of equipment designed to perform a specific task, typically a domestic one.9.remote[中文意思]遥远的[英文释义]located far away; distant.10.remote control[中文意思]遥控器[英文释义]a handheld device used to operate an electronic device from a distance.11.air conditioner[中文意思]空调[英文释义]a system or a machine that treats air in a defined, usually enclosed area via a refrigeration cycle in which warm air is removed and replaced with cooler air.12.automatic[中文意思]自动的[英文释义]working by itself with little or no direct human control.13.integrated[中文意思]综合的[英文释义]combining or coordinating separate elements so as to provide a harmonious, interrelated whole.14.integrate[中文意思]整合[英文释义]combine (one thing) with another so that they become a whole.15.sensor[中文意思]传感器[英文释义]a device that detects or measures a physical property and records, indicates, or otherwise responds to it.16.efficient[中文意思]高效的[英文释义]achieving maximum productivity with minimum wasted effort or expense.17.mode[中文意思]模式[英文释义]a way or manner in which something occurs or is experienced, expressed, or done.18.routine[中文意思]常规[英文释义]a sequence of actions regularly followed; a fixed program.19.daily routine[中文意思]日常生活习惯[英文释义]the regular, unvarying, habitual, or mechanical course of procedure.20.preference[中文意思]偏好[英文释义]a greater liking for one alternative over another or others.21.instant[中文意思]即时的[英文释义]happening or coming immediately.mand[中文意思]命令[英文释义]an order or instruction.23.obey[中文意思]遵守[英文释义]comply with the command, direction, or request of (a person or a law); submit to the authority of.24.warning[中文意思]警告[英文释义]a statement or event that indicates a possible or impending danger, problem, or other unpleasant situation.25.constant[中文意思]不断的[英文释义]occurring continuously over a period of time.26.early on[中文意思]在早期[英文释义]at an early stage in a process or course of events.27.abnormal[中文意思]不正常的[英文释义]deviating from what is normal or usual, typically in a way that is undesirable or worrying.28.critical[中文意思]关键的[英文释义]of crucial importance to the success or failure of something.29.cancer[中文意思]癌症[英文释义]a disease caused by an uncontrolled division of abnormal cells in a part of the body.30.potentially[中文意思]潜在的[英文释义]having the capacity to develop into something in the future.31.potential[中文意思]潜在的[英文释义]having or showing the capacity to become or develop into something in the future.32.leak[中文意思]泄露[英文释义](of a container or covering) accidentally lose or admit contents, especially liquid or gas, through a hole or crack.33.electrical[中文意思]电的[英文释义]operated by means of electricity.34.wiring[中文意思]电线[英文释义]the different types of electrical conductors and insulators used to carry electricity and data.35.wire[中文意思]金属线；电线[英文释义]a length of metal thread or rod.36.detect[中文意思]发现[英文释义]discover or identify the presence or existence of.37.relevant[中文意思]相关的[英文释义]closely connected or appropriate to what is being done or considered.38.catch fire[中文意思]着火[英文释义]accidentally become ignited.39.fantasy[中文意思]幻想[英文释义]the faculty or activity of imagining things that are impossible or improbable.40.innovation[中文意思]创新[英文释义]the action or process of innovating.41.available[中文意思]可用的[英文释义]able to be used or obtained.42.in this sense[中文意思]在这个意义上[英文释义]in this particular interpretation or meaning.43.nevertheless[中文意思]然而[英文释义]in spite of that; notwithstanding; all the same.44.structure[中文意思]结构[英文释义]the arrangement of and relations between the parts or elements of something complex.45.security[中文意思]安全[英文释义]the state of being free from danger or threat.46.crime[中文意思]犯罪[英文释义]an action or omission that constitutes an offense that may be prosecuted by the state and is punishable by law.bine[中文意思]组合[英文释义]unite; merge.48.nanobot[中文意思]纳米机器人[英文释义]a machine or robot that is built on the scale of nanometers.49.artificial[中文意思]人工的[英文释义]made or produced by human beings rather than occurring naturally.50.artificial intelligence[中文意思]人工智能[英文释义]the theory and development of computer systems able to perform tasks that normally require human intelligence, such as visual perception, speech recognition, decision-making, and translation between languages.51.clone[中文意思]克隆[英文释义]make an identical copy of.52.predict[中文意思]预测[英文释义]say or estimate that (a specified thing) will happen in the future or will be a consequence of something.53.prediction[中文意思]预测[英文释义]a statement about what will happen or might happen in the future.54.forecast[中文意思]预测[英文释义]predict or estimate (a future event or trend).55.occupation[中文意思]职业[英文释义]a job or profession.56.oppose[中文意思]反对[英文释义]disapprove of and attempt to prevent, especially by argument.57.hence[中文意思]因此[英文释义]as a consequence; for this reason.58.cease[中文意思]停止[英文释义]bring or come to an end.59.deceased[中文意思]已故的[英文释义](of a person) dead.60.absence[中文意思]缺席[英文释义]the state of being away from a place or person.61.rural[中文意思]农村的[英文释义]in, relating to, or characteristic of the countryside rather than the town.62.advocate[中文意思]支持者[英文释义]a person who publicly supports or recommends a particular cause or policy.63.emphasis[中文意思]强调[英文释义]special importance, value, or prominence given to something.64.luxury[中文意思]奢侈品[英文释义]a state of great comfort or elegance, especially when involving great expense.65.keep in touch with...[中文意思]与……保持联系[英文释义]maintain communication with someone by letter, telephone, etc.66.career[中文意思]事业[英文释义]an occupation undertaken for a significant period of a person's life and with opportunities for progress.67.prospect[中文意思]前景[英文释义]the possibility or likelihood of some future event occurring.68.resist[中文意思]抵抗[英文释义]withstand the action or effect of.69.resistance[中文意思]抵抗[英文释义]the refusal to accept or comply with something; the attempt to prevent something by action or argument.70.paragraph[中文意思]段落[英文释义]a distinct section of a piece of writing, usually dealing with a single theme and indicated by a new line, indentation, or numbering.71.signpost[中文意思]路标[英文释义]a sign giving information such as the direction and distance to a nearby town, typically found at a road junction.72.essay[中文意思]文章[英文释义]a short piece of writing on a particular subject.73.accurate[中文意思]准确的[英文释义](of information, measurements, statistics, etc.) correct in all details; exact.74.librarian[中文意思]图书管理员。
新视野大学大学第三版读写教程第三册-完型填空答案
Where there is a will, there is a way.This proverb means that if you are really determined to do something, however difficult it might be, you will 1)------(eventually) find a way to do it well.The 2)------(premier) point is that you must have the will to achieve success.Ninety percent of the failures that occur are due to the fact that there is no strong will involved. Many people simply say that they want something, but they do not make any 3)------(endeavor) to achieve it.So, instead of getting it, they use the poorest excuse to explain the situation away.On many occasions, people tend to 4)------(bypass) every minute obstacle, making the objective impossible to attain.In reality, if they have the will to succeed, they can get rid of the 5)------(handicaps) and achieve their goals.Only those with a(n) 6)------(committed) and focused will and spirit can fight their way to final victory.Many a famous man has the same experience.They have 7)------(attained) their prestige because they have had the will to 8)----(transcend) apparently insuperable (无法克服的) obstacles.Many artists, statesmen, writers and inventors have managed to succeed because they possess a fierce will, which has helped them to accomplish major 9)------(feats).Therefore, we can see that the main thing which one needs is a strong will.Weak-willed people never climb to the top.They collapse at the 10)------(slightest) use of force against them.Strong-willed people, on the other hand, will stand up against all odds and will make it a point to succeed.Social anxiety symptoms often begin during adolescence.It's a developmental process that is 1)------(characterized) by profound psychological changes, especially in terms of how we relate to others.One of the most frustrating 2)------(aspects) of the adolescent years is the tendency for self-focus and a decrease in the 3)------(amount) of focus we have for the feelings and needs of others.While these changes are fairly universal, those of us who were born with a shy temperament (性格) can carry the adolescent fears, which may never 4)------(recede) , into adulthood.An anxious temperament causes our brains to react forcibly when 5)------(exposed) to the stress of sudden awareness of our peers and gradually we become more and more vulnerable. Our brains label the fear of exposure or embarrassment as highly dangerous.This may result in a(n) 6)------(vicious) circle for many years: excessive self-consciousness and inhibition when we feel we are being observed.To cope with the problem, I would like to 7)------(challenge) you to strive for increased focus on other people, in place of your 8)------(excessive) focus on yourself.Yes, I know, this is easier said than done.The fear may cause you to feel that you will lose control or make a fool of yourself when you are in the spotlight (聚光灯).But if you begin to build a new response, in 9)------(reaction) to your fears, you will gradually build up a stronger and more positive response.Remember, don't let self-consciousness 10)------(paralyze) you! Be courageous!三．Audrey Hepburn was a beautiful actress and model, who became one of the most successful and well-known actresses in the film 1)------(domain).She was a fashion icon and role model for women all over the world, helping to 2)------(define) a particular type of fresh, vulnerable, elfin (小精灵似的) beauty.Today's 3)------(popularity) of the slim fashion model is due to Audrey Hepburn's influence. Although she appeared frail (脆弱的), she was 4)------(mentally) strong.At the end of her acting career when she entered a(n) 5)------(diplomatic) career as a Goodwill Ambassador for UNICEF, she was so solidly 6)------(committed) to her cause that she was held in highest esteem (尊重) by even the most hardened politicians.Audrey originally started working for UNICEF in 1954, doing radio presentations.She always said it was happy to 7)------(devote) her life to helping impoverished (穷困的)children after her own good fortune in 8)------(surviving) the hardship of the Nazi occupation of Holland.She began her permanent ambassadorship in 1988 and 9)------(embarked) on trips to many countries.She was always positive: "People in these places don't know Audrey Hepburn, but they recognize the name UNICEF. When they see UNICEF their faces light up, because they know that something is happening."In 1992, her 10)------(humanitarian) work with those in need was recognized when she was awarded the Jean Hersholt Humanitarian Award by the Academy of Motion Picture Arts and Sciences for her contribution to humanity.四．"Why would you leave behind your comfortable bed, your home, your family and friends? Why do you want to go alone?" When you are living out of a backpack for a period of time, you may often get questioned why.I seldom get time to sit down and 1)----(contemplate) the reason I travel, but I believe that you only begin to truly live once you step outside of your 2)----(comfort) zone.My first overseas trip was at 14 years old, which 3)----(sparked) my curiosity for the world.Since finishing high school I have 4)----(ventured) through various countries and been amazed by all the 5)----(diverse) cultures scattered around the globe.My eyes are my greatest asset as they have 6)----(witnessed) the most beautiful scenes that replay in my mind every day: 7)----(stunning) landscapes,friendly locals, breath-taking architecture, and food that makes your mouth water once your eyes catch a(n) 8)----(glimpse).Traveling teaches you to be independent in the most 9)----(positive) way.I know how to depend on myself, go out and meet people, and not let anyone else's expectations10)----(dictate) my life.Every day I see my dream and every day it's in a new place.I am 22 years young.I quite agree with Anthony Bourdain, "If you're 22, physically fit, hungry to learn and be better, I urge you to travel.Find out how other people live and eat and cook. Learn from them, wherever you go."五．In a study conducted in the UK, it was found that only four out of every five 1)----(employees) were happy at work.Surprisingly, contrary to popular 2)----(notion) , friendly, supportive colleagues and a good manager, instead of the salary or the love for the work, have been found to be the 3)----(primary) causes of happiness at work.So, how do you keep your spirits up and, at the same time, 4)----(foster) a sense of joy on the job? Here is one of the tips to help you on your way to finding happiness and complete job satisfaction in the workplace.Start with a positive outlook.Happiness is a state of mind; it 5)----(reflects) an attitude, though not many people realize it.Staying happy at work is totally based on your 6)----(motivations) and on a positive outlook toward your job, not on 7)----(monetary) rewards or material gain.Dwelling on (老是想着) the good 8----(aspects) of the work rather than rattling on and on (对...喋喋不休) about what makes you unhappy is the basic key to happiness.Negativity and 9)----(gossiping) about bad things may be easy, but it is looking at the bright side that makes for the challenging part of a job.As Francesca Reigler puts it, "Happiness is an attitude. We either make ourselves 10)----(miserable), or happy and strong. The amount of work is the same."八．Laughter is a(n) 1)----(automatic) response to being touched by a tickle (搔痒) –a natural response from the child.This puts the tickler in 2)----(charge) of how much or how long the child laughs.We adults don't read children's minds, but we often have a(n) 3)----(presumption) that we can.So we usually think we're aware of what's too much tickling and when to stop.But it is possible to trap our children without knowing it.We parents become 4)----(attached) to tickling because it seems to be a(n) 5)----(handy) shortcut to laughter.We wish that our children are happy and love us, and tickling becomes our shortcut to get assured.Rather than forcing laughter in this way, we can 6)----(confer) upon them inner confidence if we will get down on the floor and invite them to be in playful physical 7)----(contact) with us.If we find ways to give them much of the power, our children will laugh and laugh.Games like "I have a hundred hugs for you!" or "Where's Jared? I know he's around here somewhere." or "Oh, no! I can't get this horsy rider off my back!"let children laugh and laugh as we try to catch them, or try to find them, or try to 8)----(bounce) them off our backs, and fail over and over.The physical contact that requires more creativity than tickling allows us to 9)----(tumble) around, to press our heads against their stomachs here and there for a second, and to manage an embrace before they make another daring escape.We get our affection across without trapping our children.And we give them a chance to be inventive as they use their 10)----(intellect) to figure out a hundred ways to outsmart us.。
简单少儿英语小短文带翻译-新的耕种方式
简单少儿英语小短文带翻译-新的耕种方式Tuan was a farmer in Vietnam. For decades, he had been struggling to rid his family of hunger. However, it always confused him how to expand the output of his crops. This disturbing problem led to his regretting being a farmer. He would rather have chosen another job.One day, when skimming through a newspaper, Tuan read a comment on Yuan Longpin. He underlined Yuan’s nationality and occupation, and then focused on his discovery and the statistics of his research. He found the knowledge Yuan circulated very practical. Therefore, he made a summary and began to build up a new farming method. He planted supergrain of rich nutrition and equipped himself to keep hiscrops roots free from bacteria and pests. He also enriched minerals in the soil while reducing chemical fertilizers. Though it cost him more time and freedom, he was full of hope.The next year, Tuan was sunburnt but satisfied with his production very much. Thanks to Yuan Longpin, he not only won the battle against hunger, but he could also export his crops abroad.新的耕种方式俊是一名越南的农民，几十年来，他都一直在努力使家人摆脱饥饿。
专业英语(土木工程 路桥方向)李嘉 第三版 翻译
1、土木工程中的各种业务1、土木工程中的各种业务Engineering is a prof ession, which means that an engineer must have a specialized university education. Many government jurisdictions also have licensing procedures which require engineering graduates to pass an examination, similar to the examination f or a lawyer, bef ore they can actively start on their careers.工程是一种专业，这就是说工程师必须受过专业大学教育。
许多政府管辖部门还有（一套）认证程序，这一程序要求工科毕业生在他们能积极地开始他们的职业生涯之前，通过（认证）考试, 这种考试类似于律师职业里的律师考试一样。
In the university, mathematics, physics, and chemistry are heavily emphasized throughout theengineering curriculum, but particularly in the f irst two or three years. Mathematic is very important in all branches of engineering, so it is greatly stressed. Today, mathematics includes courses in statistics, which deals with gathering, classif ying, and using numerical data, or pieces of inf ormation. An important aspect of statistical mathematics is probability, which deals with what may happen when there are dif f erent f actors, or variables, that can change the results of a problem. Bef ore the construction of a bridge is undertaken, f or example, a statistical study is made of the amount of traf f ic the bridge will be expected to handle. In the design of the bridge, variable such as water pressure on the f oundation, impact, the ef f ects of dif f erent wind f orces, and many other f actors must be considered.大学里,工科课程中着重强调数学、物理,和化学,尤其在开始的两到三年。
高一(17)it的用法讲解、练习+七选五+完形填空+短文改错
高一(17)i t的用法讲解、练习+七选五+完形填空+短文改错-CAL-FENGHAI-(2020YEAR-YICAI)_JINGBIAN高一英语暑期复习材料（17）词汇巩固A New Farming Way 新的耕种方式Tuan was a farmer in Vietnam. For （decade）, he had been (努力做)rid his family of hunger. However, it always (使……困惑) him how to expand the output of his crop s. This （disturb）problem (导致) his （regret） being a farmer. He (宁愿) have chosen another job.One day, when skim ming through a newspaper, Tuan read a comment on Yuan Longpin. He underline d Yuan’s nationality and occupation, and then (集中注意力) his discovery and the statistic s of his research. He found the knowledge Yuan circulate d very practical.（因此）, he made a summary and began to （建立） a new farming method. He planted super grain of rich nutrition and （装备；配备） himself to keep his crops root s free from bacteria and pest s. He also enriched mineral s in the soil while_______________(reduce) chemical fertilizer s. Though it cost him more time and (free), he was full of hope.The next year, Tuan was sunburnt but (对……满意) his production very much.________________ (幸亏) Yuan Longpin, he not only won the battle against hunger, but he could also ___________（出口）his crops abroad.It的用法一、人称代词1，it的最基本用法是作代词，主要指刚提到的事物，以避免重复:①They watched the train until it disappeared in the distance.2.，也可以指动物或婴儿(未知性别的婴儿或孩子):②Is this your dog？No, it isn’t.③They got a baby and it was a ten-pounder3.，也可指抽象事物或指抽象环境和情景:③I hate it when people talk with a full mouth.．二、.非人称代词1.it有时并不指具体的东西而泛指天气、时间、日期、距离、价值、度量、温度、环境等：⑴.指天气：It is a lovely day, isn’t it⑵.指时间: It was nearly midnight when she came back.⑶.指日期:It is April First today.⑷.指距离:It is some 3000 kilometers from Beijing to Guangzhou.⑸.指价值:It is three dollars.⑹.指温度:Today it is 30 degrees centigrade.三、其他用法1.在句子的主语不太明确时充当主语，表示谁在做某事：①Who is it thereIt's I (me/you/he.....).②I thought it was Mary, but it was not she.③Her face lighted when she saw who it was.2.泛泛的指某件事： (有时泛指一般情况)①It doesn’t matter.②It is a shame, isn’t it?③How is it going(情况怎样)④It says in the newspaper that......3.it用在一些词组中，it 没有特别的意思The last train's gone. Come on, we'll foot it.(来，咱们步行吧。
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arXiv:cond-mat/0010453v1 [cond-mat.stat-mech] 27 Oct 2000
G. De Smedta,1 , C. Godr` echeb,2 , and J.M. Lucka,3
t 0 t 0
du
1 ± σu , 2
(1.2)
du σu ,
(1.3)
where Mt , the temporal mean of σt , is hereafter referred to as the ‘mean magnetization’ by analogy with physical situations where σt represents a spin. The distribution of the occupation time bears information on the statistics of persistent events of the process beyond that contained in the persistence exponent [5, 6, 7, 8, 9, 10, 11]. This exponent governs the decay ∼ t−θ of the survival probability of the process, that is the probability that the process did not cross the origin up to time t. Actually, for the present case, the determination of θ is trite, as shown by a simple reasoning [4]: the probability for the Brownian process yt′ not to change sign up to time t′ is known to decay as (t′ )−1/2 , hence for the original process as t−α . This shows that θ = α. 2
a
பைடு நூலகம்
b
Abstract We revisit the work of Dhar and Majumdar [Phys. Rev. E 59, 6413 (1999)] t on the limiting distribution of the temporal mean Mt = t−1 0 du sign yu , for a Gaussian Markovian process yt depending on a parameter α, which can be interpreted as Brownian motion in the scale of time t′ = t2α . This quantity, for short the mean ‘magnetization’, is simply related to the occupation time of the process, that is the length of time spent on one side of the origin up to time t. Using the fact that the intervals between sign changes of the process form a renewal process in the time scale t′ , we determine recursively the moments of the mean magnetization. We also find an integral equation for the distribution of Mt . This allows a local analysis of this distribution in the persistence region (Mt → ±1), as well as its asymptotic analysis in the regime where α is large. We finally put the results thus found in perspective with those obtained by Dhar and Majumdar by another method, based on a formalism due to Kac.
1
1
Introduction
dyt √ = 2α tα−1/2 ηt , dt
Consider the stochastic process yt defined by the Langevin equation (1.1)
where α is a positive parameter, and ηt is a Gaussian white noise such that ηt = 0 and ηt1 ηt2 = δ (t2 − t1 ). In the new time scale t′ = t2α , this process satisfies the usual Langevin equation for one-dimensional Brownian motion, dyt′ = ζt′ , dt′ where ζt′ is still a Gaussian white noise, with ζt′ = 0 and ζt′1 ζt′2 = δ (t′2 − t′1 ). The process defined by (1.1) is a simple example of subordinated Brownian motion [1]. As Brownian motion itself, it is Gaussian, Markovian, and non-stationary. This process appears in various situations of physical interest. For instance, it is described in [2] as a Markovian approximation to fractional Brownian motion. It also 1 appears in ref. [3] for the special case α = 4 , as describing the time evolution of the total magnetization of a Glauber chain undergoing phase ordering. Dhar and Majumdar [4] raised the question of computing the distribution of the occupation time of this process, that is the length of time spent by the process on one side of the origin up to time t, Tt± = where σt = sign yt , or equivalently of Mt = 1 t
, the distribution of the fraction of time spent on one side of the When α = 1 2 origin by a random walker, or by Brownian motion, is given, in the long-time regime, 1 by the arcsine law [12, 1]. In contrast, when α = 2 , the explicit determination of this distribution, or equivalently of the distribution of Mt , seems very difficult. However, as shown in [4], in the long-time regime, the computation of the asymptotic moments Mtk can be done recursively, using two different methods, yielding the same results. The first method relies on a formalism due to Kac [13], while the second one originates from ref. [5]. The method used in ref. [5] can be applied to any (smooth) process for which the intervals of time between sign changes are independent, when taken on a loga¯. It eventually leads to a recursive rithmic scale, with finite (i.e., non zero) mean ℓ determination of the moments of Mt , as t → ∞ (see equation (3.9) below). Dhar and Majumdar make the observation that, since relations (3.9) are indepen¯, they can be applied to the determination of the moments of Mt for the dent of ℓ process (1.1). Comparing the resulting expressions of the moments thus obtained to those derived by their alternative method shows that this is indeed the case. However it is not obvious to understand why relations (3.9) hold for the (nonsmooth) process (1.1), since the assumptions made in order to derive them do not hold for such a process. In particular while, for the class of models with independent ¯ (for which the method of ref. [5] time intervals on a logarithmic scale, and finite ℓ has been devised), it is natural to work in a logarithmic scale of time, since the mean ¯, this is not so in the number of sign changes between 0 and t scales as Nt ≈ (ln t)/ℓ ¯ asymptotically vanishes, and the mean number of sign changes present case, since ℓ scales as Nt ≈ 2 π −1/2 tα [11]. The validity of relations (3.9) for the process (1.1) therefore requires an explanation. In the present work, we revisit and extend the study done in [4]. We first give a new derivation of the asymptotic expressions of the moments Mtk . We start from the same premises as in ref. [5], then follow another route –more adapted to the process under study– because of the difficulties encountered in applying step by step the method of ref. [5] to the present case (sections 2-5). We then identify the symmetry properties of the distributions of the random variables that appear in the computations, and derive a functional integral equation, the solution of which yields the distribution of Mt (section 6). This approach is first checked on 1 the case α = 2 (section 7). It is then successively applied to the study of the local behavior of this distribution in the persistence region, for general α (section 8), and to the large-α regime (section 9). We finally discuss some aspects of ref. [4]. We explain why a formal application of the method of ref. [5] to the present case is only heuristic, and give a new interpretation of the results obtained in [4] with the method of Kac, under the light of the present work (section 10). 3