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2019年06月20日 18:05:03来源:普及互动

Science and Technolgy科技Mars exploration火星探测How to land a Mini on Mars;迷你;漫游车如何登陆火星The biggest and fanciest Mars rover so far will soon blast off from Florida迄今为止最大和最新奇的火星探测器即将于佛罗里达州发射升空EARTH excepted, the most probed and prodded planet in the solar system is Mars. Besides the assortment of craft that have flown by it or gone into orbit around it, three robotic buggies equipped with cameras and scientific instruments have roamed the Martian surface on behalf of NASA, Americas space agency, since 1997.在地球以外的太阳系内,人类探测和接触次数最多的星球要算火星了。除了飞越火星或进入其轨道运行的花样繁多的航天器之外,美国宇航局自1997年以来已有三辆机器人漫游车登陆火星,它们搭载着照相机及各种科学仪器,一直在火星上行驶漫游。If all goes according to plan, they will soon be joined by a fourth. On November 26th a new rover, Curiosity, will ascend from Cape Canaveral. If it gets there in one piece, it will examine the climate and geology of Mars and look for any signs of life that might have arisen.如果一切按计划进行,火星将很快迎来它们的第四个兄弟---;好奇;号火星探测器,它将于11月26日在卡纳维拉尔角发射升空。;好奇;号一旦安全着陆,将会对火星展开气候及地理环境检测,并寻找可能已经存在的生命迹象。The first of NASAs rovers, Sojourner, which reached Mars in 1997, was 65cm long and weighed (on Earth, where the gravitational pull is 2? times Marss) 10kg. Spirit and Opportunity, its twin successors, were larger, at 1.6 metres and 170kg. Curiosity, by comparison, is a monster. At 3 metres and 900kg it is the size of a small car. It also uses different technology. The other three rovers were powered by solar panels. Curiosity is powered by plutonium. (Not a full-scale reactor, but a generator that turns the heat of radioactive decay into electrical energy.) This brings three advantages. First, it allows Curiosity to carry more power-hungry scientific instruments than previous rovers. Second, it permits the rover to work through the Martian winter. Third, it avoids the problem of dust accumulating on the solar panels, which gradually sapped the strength of its predecessors.美国宇航局第一个火星探测器;索杰纳;号于1997年到达火星,该探测器长65厘米,重10公斤(地球引力是火星的2.5倍)。随后到达的是;双子;火星探测器;勇气;号及;机遇;号,它们体积比;索杰纳;号稍大,长1.6米,重170公斤。与前三者相比,身长3米,重达900公斤,小汽车般大小的;好奇;号可算是个庞然大物了,而且它采用了不同的技术。前三个探测器由太阳能电池板提供能量,而;好奇;号采用核动力;钵;供能。(它不是完整的反应堆,而是具备将放射性衰变转换成电能的发电机)。采用核动力有三个好处。第一,它允许携带更高能耗的科学仪器;第二,它能保;好奇;号在火星的冬季环境下工作。第三,它克了太阳能电池板由于蒙尘而使前者漫游车电力逐渐下降的缺点。Curiositys size makes getting it safely onto the Martian surface tricky. Previous rovers have deployed parachutes to slow their descents, and have then crashed into the ground using airbags to cushion their impacts. Curiosity is too massive for that approach to work. Instead, NASA hopes to deposit it on Mars using a contraption it has dubbed a skycrane.;好奇;号体积庞大,这使其安全着陆火星的工作变得十分棘手。之前的漫游车的下落过程采用降落伞减速,并采用气袋来缓冲撞击地面造成的冲击。但这种方法对于体积庞大的;好奇;号却不适用。美国宇航局意图采用一个设计精巧的;空中起重机;使;好奇;号安全着陆火星。As with the other rovers, Curiositys mother ship will rely on heat shields and air-resistance, and then on a parachute, to slow its arrival. But at an altitude of 1.6km a specially designed descent stage bearing the rover will drop away from this vehicle. The descent stage has eight rocket motors on its corners. These will slow its fall to a relatively sedate 0.75 metres a second. When it is about 20 metres above the surface, the rover will be lowered from it on wires and deposited gently onto the Martian landscape. The cables will then be cut with explosives, the descent stage will fly off and crash land elsewhere, and Curiosity will begin its mission.与其它火星漫游车相同,;好奇;号运载船也依靠防热罩,空气阻力及降落伞实现减速到达。但不同的是,在到达距火星地表1600米的高空时,经过特殊设计并承载着漫游车的下降段将会脱离运载船。下降段底部四周装有8个火箭发动机,能使下降速度达到每秒0.75米相对缓慢的速度。在距离地面20米时,下降段用线缆将漫游车向下悬吊直至缓慢放置到火星表面。然后线缆引爆切断连接,下降段飞离漫游车在火星其它地方坠落,接下来;好奇;号就可以开始执行任务了。That, at least, is the theory. But the skycrane has never been used before, and there is plenty else that could go wrong. Indeed, Mars has something of a reputation for destroying spacecraft. Around half the missions sent there since the first Soviet attempts in 1960 have failed to arrive. A conversation on the subject in 1964, between a journalist and John Casani, a NASA scientist, spawned the idea of a Great Galactic Ghoul, a malevolent creature that prowls the space-lanes between Earth and Mars, dining on unfortunate spacecraft.但这毕竟是从理论角度而言的。;空中起重机;从未使用过,在实际中还可能出现诸多其它差错。事实上,火星也充当了不少航天器破坏者的角色。自1960年前苏联第一次向火星发射航天器以来,有半数左右的火星探测任务遭遇失败而无法到达火星。1964年,一名记者与美国宇航局科学家约翰·卡斯尼对此问题曾有过探讨,他们构想出一种邪恶的生物——系食尸鬼,它穿梭于地球与火星之间,运气不佳的航天器就会变成它的口中之食。The ghouls latest victim appears to have been Phobos-Grunt, an ambitious Russian mission that was intended to return to Earth with a rock sample from Phobos, the larger of Marss moons. The Russian space agencys engineers lost contact with it soon after its launch on November 8th. Limited contact had been re-established as The Economist went to press, but it is not clear whether the mission can be salvaged. NASAs engineers, rationalists though they be, will be keeping their fingers crossed on Saturday, and hoping that the ghouls appetite has thus been sated, and that it will leave Curiosity alone.最近沦为食尸鬼牺牲品的可能是俄罗斯的;福布斯-土壤;号探测器。俄罗斯此项探测任务雄心勃勃,准备让探测器从;福布斯;(火星的一颗较大卫星)上取回一块岩石样本。该探测器于11月8日发射,但俄罗斯航天局工程师们很快便与其失去了联系。截至本期《经济学人》刊印之时,俄罗斯方面已与探测器重建了一些联系,但该项任务能否挽回尚未可知。尽管美国宇航局的工程师们都是理性之人,但他们也祈祷周六的发射会给他们带来些好运气,希望届时;食尸鬼;已经酒足饭饱,不会找;好奇;号的麻烦。 /201210/203354。

  • DOES a bill that does nothing actually do something? This is not a Zen koan, but a legislative one, being tested this month in Tennessee. The bill in question required the state’s education system to encourage students to “explore scientific questions” and “respond appropriately and respectfully to differences of opinion about scientific subjects”. It also protected teachers against punishment for “helping students understand, analyse, critique and review in an objective manner the scientific strengths and scientific weaknesses of existing scientific theories.” It passed with big majorities in both chambers, and became law on April 10th when Bill Haslam, Tennessee’s governor, declined to veto it.一个没有具体措施的法案果真能“无为而治”吗?这个本月在田纳西州试行的法案可不是禅宗的公案,而是确实具有法律效力的。上述法案要求田纳西州的教育制度鼓励学生“探讨科学问题”并“包容、尊重关于科学问题的不同见解”。根据法案,教师还能“帮助学生以客观的方式理解、分析、及考察现存科学理论中的优缺点”而不受处罚。法案在参众两院以多数票获得通过,4月10日,田纳西州州长比尔-哈斯拉姆(Bill Haslam)拒绝对法案进行否决,于是该法案在当日正式生效。At issue is whether this innocuous-sounding measure is actually a back door that would allow teachers to introduce creationism and intelligent design into science classrooms. Many are sure it is. The measure drew opposition from scientists and teachers both nationally and in Tennessee. Several Tennessee-based members of the National Academy of Sciences worry that the bill would weaken science education in the state. Around 3,200 Tennesseans signed a petition urging Mr Haslam to veto the bill. And the American Civil Liberties Union (ACLU) believes the measure “undermines science education in Tennessee public schools”.目前有争议的是,这份听似无伤大雅法案是否真的为教师在讲授科学课程时向学生灌输创世说和智慧设计论开了后门。很多人认为确实如此。这份法案遭到了田纳西州及全国各地的科学家和教师的反对。美国国家科学院中几位来自田纳西州的成员担心法案会降低美国科学教育的质量。田纳西州约有3200个人签署了一份请愿书,力劝比尔-哈斯拉姆否决该法案。美国公民自由联盟则认为,该法案“破坏了田纳西州公立学校的科学教育”。Supporters of the measure, such as state Senator Bo Watson, a co-sponsor, say this is alarmist poppycock. Evolution is part of Tennessee’s science curriculum, which the bill does not change. Many state and federal court cases have not only prohibited the teaching of creationism and intelligent design in public-school classrooms, but have also restrained teachers from introducing arguments against evolution in contravention of a school district’s curriculum. The original version of the bill warned that “the teaching of some scientific subjects” including “biological evolution, the chemical origins of life, global warming and human cloning, can cause controversy”; Mr Watson cut that language out. He insists the bill is simply meant to ensure that pupils learn “critical thinking” in science classrooms.如法案联合倡议人、州参议员波-华森(Bo Watson)等法案持者说那些都是危言耸听的废话。进化论是田纳西州科学课程的一部分,该法案并没有改变这点。之前许多州法庭和联邦法庭的判例不但禁止在公立学校中讲授创世说和智慧设计论,还不允许教师违反学区课程规定讲述任何反对进化论的观点。法案中原来有句话提醒人们注意:“讲授包括生物进化论、生命的化学起源、全球变暖及人类克隆在内的一些科学题材会引起争议”;波-华森将这一句删去了。他坚称该法案仅仅是旨在确保学生们在科学课堂上学会“批判地思考”。Josh Rosenau, of the National Centre for Science Education (NCSE), asks why the bill singles out science classrooms as a place where pupils should be urged to think critically. After all, some people believe the 1969 moon landing was faked or that the Holocaust is a hoax; why not require history teachers to inform pupils of both sides of those issues, too?国家科学教育中心的乔希-罗西诺(Josh Rosenau)质问道,为何法案规定只应在科学课堂上鼓励学生批判思考。要知道,有人可认为1969年人类登陆月球是假的,还有纳粹大屠杀就是个骗局;何不要求历史老师也告诉学生关于那些事件的两种观点?Tennessee’s bill is not unusual: since 2004 similar measures have been offered in no fewer than 13 state legislatures. Only in one other state has one become law. Many such bills, including Tennessee’s, share a common parent: a “Model Academic Freedom Statute on Evolution” written and posted by the Discovery Institute, a conservative think-tank that has long advocated intelligent design. This measure protects teachers’ and students’ rights to present and hear “the full range of scientific views regarding biological and chemical evolution,” but it does little in practice. It changes no curriculum and does not expressly lobby for creationism or intelligent design. Louisiana’s measure, which has been law for nearly four years, seems to have had no discernible effects. Instead, these bills seem a particularly successful bit of signalling. They let evolution sceptics express themselves in the right place: within the law and outside the classroom.田纳西州的这个法案并不罕见:自2004年起,至少13个州中有人向立法机构提出类似的法案,除田纳西州外只有1个州的法案正式生效。这些法案中的大部分,包括田纳西州的,都有一个共同起源:由探索研究所撰写并发布的《关于进化论的学术自由法规范》。探索研究所这个立场保守的智囊长久以来都是宣扬智慧设计论的。这个法规保护了老师和学生提出、倾听“关于生物和化学进化论的所有科学观点”的权利,但并没怎么落实。法规并没有改变学校的课程,也没有明确地为创世说或智慧设计论进行游说。路易斯安娜州的法案生效已将近4年,却似乎没什么明显效果。相反,这些法案看来在传达信息方面尤有成效,它们让进化论怀疑者在恰当的场所表达了自己意见。所谓恰当,即法律之内,课堂之外。201204/180075。
  • Tapping Caterpillars毛虫的敲击声Y: I could have sworn that I heard a strange tapping sound in my house last night. It was faint but chilling. I think there must be a ghost in my house.我发誓昨天晚上在家里我听到了很奇怪的敲打声。那个声音微弱至极,但就是让人毛骨悚然。我家里是不是有鬼啊!D: Do you happen to keep caterpillars, perhaps the hook-tip moth?该不会你正好养了毛虫,或是钩翅蛾吧?Y:Why? Yes, I do. I have several little creatures. But what does that have to do with that tapping noise I heard?啊?嗯,我有养。我养了很多小动物。但那跟我晚上听到的声音有什么关系呢?D:That noise probably came from your caterpillars, and it probably means one of them invaded anothers territory.那个声音很可能就是你养的小毛虫发出的。很有可能是一只小虫闯进了另一只的领地。Y:I didnt know caterpillars were territorial.我都不知道毛虫还有领地呢!D:Well, it turns out some are. In fact, whats odd is that the hook-tip moths territorial behavior is much like that of many vertebrates, not what youd expect in an organism like a caterpillar. These caterpillars find themselves a good leaf, and then they construct a nest of silk to protect them while they feast. When another caterpillar intrudes upon the resident caterpillars territory, the resident caterpillar stops eating, retreats into its nest, and it makes tapping noises by dragging or striking its mandibles against the leaf.呃,有的是这样的。事实上,奇怪的是,钩翅蛾的占地行为更像是脊椎动物,并不像是你所想像的蛾类的占地行为。这些毛虫为自己找到一片好叶子,然后用丝筑一个巢。在毛虫“用餐”的时候,这个巢就可以起到保护作用。当另一只毛虫闯入该毛虫的领地时,“原住民”会立即停下用餐,退回巢内,借助拖拽鄂骨或是用鄂骨敲击叶子发出敲击声,以此威胁入侵者。Y:What does the intruder do?那么,入侵者又会怎么做呢?D:Often the intruder makes the sound as well and may end up attacking the residents nest by biting through some of the silk strands. Caterpillars dont make this noise anywhere but in the nest, and scientists say this behavior suggests that the rivals are sizing each other up. They also suggest that the sounds may function to attract the attention of predators, in which case the intruder would be rather defenseless.通常情况下,入侵者同样也会制造出敲击声,到最后会咬掉“原住民”巢内的部分丝线。毛虫只会在巢内发出这样的声音。科学家指出,这是双方在衡量对方的实力。同时,还指出,这种声音还会吸引来食肉动物,在这样的情况下,入侵者在防御上就会处于明显的弱势。 /201301/221798。
  • Well, youve probably been there, stomach viruses, nasty head colds, but how would you feel if you came down with a computer virus?你可能被传染过胃病,头疼脑热,但如果电脑被你传染了,你会怎么想?No, you, not your computer.不,不是你被传染了,而是电脑。A British scientist is getting involved with a pretty weird science project he has infected himself with a computer virus.一名英国科学家现正在进行一项奇特的研究,他自己传染了电脑病毒给电脑。Thats right, he is showing how implantable biotic devices are also susceptible to computer viruses. So how does this work? With more computer chips being implanted in people for all kinds of reasons, could this become a problem in the future? Lets talk about it with Michio Kaku, theoretical physics professor and author of the book ;Physics of the Impossible;.没错,它正在研究可植入器官对人类的重要影响。可植入器官是如何影响人类的?因为各种各样的原因,电脑芯片被植入人类体内,这在未来将成为一个问题吗?让我们来和物理学教授《Physics of the Impossible》一书的作者Michio Kaku聊聊。Alright, so he did this to prove a point, he implanted one of these computer chips in himself, and it has a virus in it.这么说,他植入了一块电脑芯片,而这块芯片中有电脑病毒。Thats right, at the university of ing, he took an ID chip that we put in pets for example, infected with a virus stuck under his hand, and then as he passes his hand over an ID system, he can actually transfer the virus from his hand to another system. And thats a very important point, cause in the future, were gonna have more chips in our body and clothing.是的,在雷丁大学,他接触到一块植入宠物的ID芯片,举个例子,病毒接触到他的手,接下来他的手又接触了ID系统,很有可能他将电脑病毒从手上传播到了ID系统上。这点很重要,因为未来我们将会广泛应用植入芯片。So hes trying to show people that, you know, the way of the future is here now, and there can be problems.他向人们展示了未来的景象,而这恰恰可能出现问题。Thats right. Aly, thousands of Americans have pacemakers, they have cochlear implants to correct hearing problems. In the future, even aspirin pills could have chips in them with TV cameras, they aly exist, you swallow them, they take pictures of your stomach from the inside, this is the new meaning for the expression ;intel inside;.是的,事实上已经出现问题了,在美国有成千上万人使用心脏起搏器或人工耳蜗以解决各种问题。在未来,即使是阿司匹林药片也有可能被植入摄像头芯片,事实上,现实生活中已经有了,我们吞下它,它拍摄胃里的图片,这点全新地诠释了“英特尔内核”这句广告词。So, for instance, I got my staff ID, its got a little raido chip in it, I swipe it to get into the building here at Fox. Thats what hes got except in a little chip in his hand, he put a virus in it intentionally, and apparently now when he swipes in to this computer system, some of the other professors at his university, their cards get infected, or get the, give him access to same areas they are in.例如,在我的ID件上有一个小的芯片,我用它来进入大楼。手里只是拿了小小的芯片,如果有意地置入芯片并用手接触电脑系统,那么我们校园内教授们的车将被感染,也许会允许我走进车库。Thats right, so he did it not as a simplicity stunt. He did it to show that in the future when chips, cost maybe a penny of piece, theyre gonna be, for example, in our clothing, maybe even in our contact lens. Well have the internet in our contact lens, as we blink them then were online, and these systems are susceptible to viruses.是的,这不仅仅是个有噱头的假设,而是未来有可能出现的情况。将来的芯片也许只有小小的一片,举个例子,它们能被植入到人们的衣上,甚至隐形眼镜上。我们能用隐形眼镜上网,一眨眼就能上网,而这些系统都很容易受到病毒影响。But pacemakers things like that, you dont want somebody infecting your pacemaker with a computer virus.但像心脏起搏器这类芯片,没人希望它们感染病毒。Thats right, so weve gonna have to have passwords, special user ID codes, even for pacemakers, cochlear implants, and even for a clothing in the future.是的,所以我们需要密码,和用户账户,尤其是心脏起搏器,人工耳蜗这种芯片,甚至是未来的装。Michio Kaku, thank you.谢谢你,Michio KakuJane...Well, some of the breaking news.节目交回给Jane……好了,这就是今天的即时新闻。be susceptible to 易受到影响的注:本篇文章英文来自普特论坛,译文属原创,,。201206/187641。
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