【转帖】TOEFL 背景知识

了解一些背景知识，有助于提高听力和阅读水平。

背景知识（BACKGROUND KNOWLEDGE）（转自太傻）

听力背景知识

长段子中的4的背景知识: Troy 特洛伊

“荷马史诗”包括《伊利亚特》和《奥德赛》两部长诗，被认为是古希腊最伟大的作品，也是欧洲文学中最古老、最杰出的叙事诗。相传史诗的作者是古希腊盲诗人荷马。他生于爱奥尼亚（今土耳其西海岸），生存年代约是公元前8世纪的后半叶。

《伊利亚特》共24卷，15693行，记载了希腊联军攻陷特洛伊城的10年战争，而主要描述战争最后一年的一个事件，着重描绘了希腊英雄阿基里斯的的伟大形象。

相传在古希腊的弗提亚地方，有个叫珀琉斯的国王举行婚礼。他邀请了奥林匹斯山上的众神出席，却把专管争吵的女神厄里斯给忘记了。厄里斯便挑起是非，偷偷把一个写着“送给最美丽的女神”的金苹果放在了婚礼宴席上。参加喜宴的天后赫拉、智慧女神雅典娜、爱与美之神阿芙罗狄蒂（即罗马神话中的维纳斯）都认为自己是美丽的，应该得到这个金苹果，于是争吵起来。天神宙斯无法，只得让她们去特洛伊，让特洛伊王子帕里斯判定金苹果该给谁。当3位女神见到帕里斯后，都争着向他许愿：赫拉愿给他权力和财宝；雅典娜愿给他胜利和智慧；阿芙罗狄蒂愿让他挑选世界上最美丽的女子为妻。结果，帕里斯把金苹果判给了阿芙罗狄蒂。阿芙罗狄蒂便与帕里斯约定帮他得到世界第一美女。

大约在公元前12世纪，希腊半岛上建立了许多小王国，斯巴达是其中的一个。一天，斯巴达王宫来了两位尊贵的客人，他就是特洛伊国王普里阿摩斯和他的二儿子帕里斯。特洛伊是小亚细亚半岛（今土耳其）上的一个小王国。斯巴达国王米雷劳斯以隆重的礼节欢迎两位贵宾，连年轻的王后海伦也亲自出来接待。海伦是当时全希腊最美丽的女人。帕里斯禁不住看了她两眼，顿时动心。海伦见了这位英俊的王子，也感到满心欢喜。

当晚，趁斯巴达国王外出的时候，帕里斯在阿芙罗狄蒂的帮助下，拐走了海伦，乘船逃回特洛伊。

蒙受奇耻大辱的斯巴达国王，立刻找到他的哥哥、另一个小国迈锡尼的国王阿加米农商量，决定向全希腊各王国求助。于是，以阿加米农为统帅，组织了10万希腊联系，乘坐1013艘战船，越过爱琴海攻打特洛伊城。战争进行了10年之久，希腊世界的英雄们纷纷登场出战。其中主将阿基里斯骁勇善战，伊萨卡岛的国王奥德修斯留下美丽的妻子皮娜洛普和刚出生的儿子特勒马卡斯，也加入了希腊联军。

《伊利亚特》正是从战争的第10年初开始描写的。这个时候，战争已僵持不下，而希腊联军内部也发生了矛盾。当时，希腊联军的统帅阿加米农夺走了主将阿基里斯心爱的女俘虏布里塞斯，屡建奇功的阿基里斯恼怒万分而拒绝出战，使希腊联军陷入困境，阿加米农、奥德修斯等将领都受了伤。而特洛伊王国主将、太子赫克托在宙斯和阿波罗的鼓动下，反倒向希腊联军营寨发起了进攻，企图烧毁希腊人的战船，情况万分危急。这时，阿基里斯把自己的盔甲和盾牌送给好友帕特洛克拉穿上，让他出阵应战。特洛伊人以为是希腊英雄阿基里斯本人出战了，纷纷不战而退。精明的赫克托仔细观察发现，穿阿基里斯盔甲的那个希腊将领，并不是阿基里斯本人，便出其不意地冲上前，把帕特洛克拉杀死。

悲痛欲绝的阿基里斯，再也按捺不住了，决定与阿加米农和好，重新参战，要与赫克托决战。阿基里斯身先士卒，冲锋陷阵，把特洛伊军队打得大败，并亲手杀死了赫克托。双方分别为帕特洛克拉和赫克托举行了隆重的葬礼，并约定双方休战12天。《伊利亚特》写到此就结束了。

根据其他一些文献记载，战争继续进行。据说，特洛伊军队发誓要报仇，但要杀死阿基里斯是很困难的。传说在阿基里斯出生后，被母亲提着脚跟浸在冥河水中，所以他全身刀枪不入，只有脚跟因被母亲握着没有被冥河水浸过，所以留下一个致命弱点。帕里斯知道了阿基里斯的这个弱点，从远处用暗箭射中他的脚跟，杀死了英雄阿基里斯。因此，直到现在，欧洲人还把“致命伤”叫做“阿基里斯的脚跟”。之后，帕里斯也被希腊弓箭手射死。

最后，足智多谋的奥德修斯献出了“木马计”，米阿加米农所采纳。希腊军队佯败，弃一匹巨大的木马而逃。特洛伊人被骗，把“战利品”——木马拖进城里。当晚，藏在木马腹内的20名希腊士兵杀出，打开城门，里应外合，特洛伊立刻被攻陷，遭到大肆杀掠和大火，全城被毁。老国王和大多数男人被杀死，妇女和儿童被出卖为奴，海伦又被带回希腊，持续10年之久的战争终于结束。

3000多年过去了，“木马计”的故事却一直在全世界流传着。

《奥德赛》（意指奥德修斯之歌）、共24卷、12110行。叙述特洛伊战争后，希腊英雄、伊萨卡岛国王奥德修斯在海上漂流10年，经历种种艰险，最后回到家乡与家人团聚的故事。

希腊联军在特洛伊城内大肆屠杀和掠夺后，回国途中触怒了天神。天神掀起了一阵大风暴，大多数战船沉没了，剩下的少数人，由奥德修斯带领，在大海上漂泊。他和同伴最初是往北航行，结果遇到土人袭击，接着转向西航行，不幸又遭遇大风暴，被吹到北非岸边的食莲人的国度。在那里，有几个奥德修斯的属下吃了食莲人吃的一种甜果，沉醉在甜味中而不愿再回家乡。奥德修斯便带领其余的人回船后继续向北航行，不久来到了独眼巨人族的领地。独眼巨人波吕斐摩斯（海神波塞冬的儿子）非常残忍，把奥德修斯和他带上岸的12名属下关进岩洞里，每天吃掉2个人。奥德修斯用酒灌醉巨人，削尖一根巨大的木杆，用火烤热后，和4名同伴一起捅瞎了巨人的独眼，得以逃生。

南下的奥德修斯一行人漂到了风神所在的岛。风神送给他们一只风袋，西风送他们一行往东平安地通过西西里岛和意大利半岛之间的墨西拿海峡驶入爱奥尼亚海。当他们举目可见家乡的海岸时，一直认为风袋里装有财宝的几个同伴，趁奥德修斯睡觉时，打开了风袋，结果吹起逆风，又把他们吹回风神岛。风神认为奥德修斯违逆众神的意志，把他们一行赶出岛外。

他们又漂流海上，来到据说可能位于撒丁岛和科西嘉岛之间的一个小岛，却遭到了食人族的攻击，几个同伴被吃掉。奥德修斯率其余同伴登上唯一未遭破坏的船逃回海上，漂到女巫塞西居住的艾艾伊岛。由副将欧吕洛卡斯率22人先登岛侦察。一座石造的宫殿吸引了他们。其实这就是塞西的宫殿。除欧吕卡洛斯外，大家都进入宫殿，并痛快地大吃乳酪、糖蜜、大麦和葡萄酒掺杂魔法药草的饮料，结果大伙都变成了猪。欧吕卡洛斯飞身返回船上向奥德修斯报告。奥德修斯立刻前往塞西的宫殿。他在途中遇到传令神赫美斯化身的英俊青年，获得一株可战胜魔法的魔力草，使自己免遭变猪，并用刀逼塞西恢复了同伴的原形。之后，奥德修斯在岛上停留了一年，还与塞西生下一子特勒格诺斯。

在同伴的一致要求下，奥德修斯告别塞西继续航行，在经过海妖塞壬的岛时，奥德修斯用塞西教的方法用蜡将同伴们的耳朵都封起来，再把自己绑在船桅上，这样他们才没被塞壬的甜蜜歌声引诱而断送性命。

他们在经过一个海峡时，又被女魔西拉抓走6个同伴。大家拼命划桨才脱离了险境，随后来到太阳神赫利俄斯居住的特里那基耶岛。由于粮食耗尽，几个同伴趁奥德修斯睡着之际偷杀了太阳神养的神牛。愤怒的太阳神请求天神宙斯惩罚。宙斯放出雷电击碎了他们的船，所有人都沉入海底，只剩下奥德修斯一人漂流到了仙女克吕普索的岛上，被她强留住了7年。

因女神雅典娜的请求，天神宙斯赦免了奥德修斯。奥德修斯乘坐木筏，终于回到已阔别20年的家乡伊萨卡岛。

话又说回去，当特洛伊战争结束后，奥德修斯的妻子皮娜洛普一直不见丈夫回来，有传闻他已死在异域。奥德修斯不在家时，先后有100多人聚集他家，向他漂亮的妻子求婚，并终日设宴消耗他家的财产。皮娜洛普拒绝了所有求婚者，她坚信丈夫会回来的。

奥德修斯回到自己的国家后，雅典娜女神把他变成一个流浪汉，在一个养猪人家同儿子特勒马卡斯见面。一身流浪汉打扮的奥德修斯来到宫殿，只有他的爱犬阿果斯认出昔日的主人，但高声大叫后却断了气。奥德修斯在儿子和仆人的帮助下把前来求婚的贵族恶少全部杀死，终于和妻子拥抱团聚，重新做了国王。

《荷马史诗》内容曲折离奇，语言瑰丽多彩，是古希腊艺术史上的一颗明珠。

世人了解欧洲文明的起源，总是从了解古希腊文明开始的。因为希腊人开启了西方哲学、科学、艺术、文学和历史。古希腊曾经光耀世界。但是，在1870年以前，历史学家根据当时掌握的史料，只能将希腊的历史追溯到公元前7-8世纪。尽管家喻户晓的“荷马史诗”描述了希腊史前的故事，但学者们认为，盲诗人荷马的史诗，最初是许多民间行吟歌手的集体口头创作，因而不能当作历史，只能视为神话传说。

然而，3000多年之后，一个叫海因里希·施里曼的德国商人，就是凭着《伊利亚特》和《奥德赛》的指点，在小亚细亚西北端等地获得了惊人的发现——挖掘出湮没3000多年的特洛伊古城等大量历史遗迹，于是得出震惊世界的结论：“荷马史诗”就是一部希腊史前文明史，把古希腊文明史向前推进了8-10个世纪。《奥德赛》这部几乎完全与海洋有关的叙事长诗，可以说是以地中海为舞台，根据当时海上交通非常繁盛的历史事实写成，绝非凭空杜撰的产物。在它的背后，还反映出希腊人海上交易和腓尼基人活动的情景。《奥德赛》主要舞台的地中海中部和东部海域的海底今天仍然长眠着许多古代的商船和古物。

特洛伊的繁盛并非单单依赖贸易往来，从出土的许多纺缍车可以推知，纺织品的生产才是其繁荣的重要原因。这就使特洛伊成为了同样以生产纺织品为主的迈锡尼的一个强劲竞争对手。特洛伊战争或许就是为了争夺纺织品交易霸权而引起的。

施里曼创造性的发掘所取得的辉煌成就，使他成为了现代考古学的开拓者。
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粗体字部分好象听力考试中有问题．

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汞污染　　人类活动造成水体汞污染，主要来自氯碱、塑料、电池、电子等工业排放的废水。据估计，1970～1979年全世界由于人类活动直接向水体排放汞的总量约1．6万吨；排向大气的总汞量达10万吨左右；排入土壤总汞约为10万吨，而排向大气和土壤的也将随着水循环回归入水体。 　　汞虽然是一种累积性毒物，但人体对汞具有一定的排泄能力。试验表明，成年人每天摄人0.025毫克的甲基汞，由于人体排泄能力使之不会在身体内累积，若摄入量超过人体的排泄能力，会在体内累积。日本的水俣病，就是在大脑中累积了甲基汞，损害脑组织所致。在人体其他组织中的金属汞，可能氧化成离子状态，并转移到肾中蓄积起来。人体受汞慢性中毒的临床表现，主要是神经性症状，有头痛、头晕、肢体麻木和疼痛、肌肉震颤、运动失调等。大量吸入汞蒸汽会出现急性汞中毒，其症候为肝炎、肾炎、蛋白尿和尿毒症等。这类病有严重的后遗症和较高的死亡率，还可以通过母体遗传给婴儿。在我国松花江和蓟河流域的一些渔民体内有明显的汞积累，而且已经出现了“拟似水俣病”的病人。 　　还有就是，在香港有一些人发现自己经常感冒，总感觉很累，经常头痛、失眠、颈椎痛、腰痛，而且久治不愈。经过化验，发现这些人体内的汞比一般人都高，病因就是这些人爱吃海鱼。类似的情况在日本水俣，农民的发病率就要比渔民低得多。概括地讲，在被污染的水域浅水鱼的汞含量相对较高，深海鱼类相比较来说则低得多。

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考古中的Dating Methods in ArchaeologyThe dating methods used by archaeologists vary considerably in precision and the nature of the material actually dated. Age determinations for archaeological materials may be direct or indirect. Direct dates are derived from the actual artifact, feature or ecofact to determine the age of the material. Indirect dates are based on material associated with the archaeological item of interest. For example, ash in an ancient hearth can be dated by the radiocarbon dating method (discussed below) and other material, such as pottery, stone tools, and fragments of animal bone associated with the hearth, can then be indirectly assigned the same age. This assignment, however, assumes that there is sufficient evidence indicating that both the hearth and the artifacts reflect the same contemporaneous event, thus allowing the extension of the direct date to the other related material.

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“”　　根据广义相对论，引力场将使时空弯曲。当恒星的体积很大时，它的引力场对时空几乎没什幺影响，从恒星表面上某一点发的光可以朝任何方向沿直线射出。而恒星的半径越小，它对周围的时空弯曲作用就越大，朝某些角度发出的光就将沿弯曲空间返回恒星表面。　　那幺，黑洞是怎样形成的呢？其实，跟白矮星和中子星一样，黑洞很可能也是由恒星演化而来的。　　质量小一些的恒星主要演化成白矮星，质量比较大的恒星则有可能形成中子星。而根据科学家的计算，中子星的总质量不能大于三倍太阳的质量。如果超过了这个值，那幺将再没有什幺力能与自身重力相抗衡了，从而引发另一次大坍缩。　　与别的天体相比，黑洞是显得太特殊了。例如，黑洞有“隐身术”，人们无法直接观察到它，连科学家都只能对它内部结构提出各种猜想。那幺，黑洞是怎幺把自己隐藏起来的呢？答案就是——弯曲的空间。我们都知道，光是沿直线传播的。这是一个最基本的常识。可是根据广义相对论，空间会在引力场作用下弯曲。这时候，光虽然仍然沿任意两点间的最短距离传播，但走的已经不是直线，而是曲线。形象地讲，好象光本来是要走直线的，只不过强大的引力把它拉得偏离了原来的方向。　　更有趣的是，有些恒星不仅是朝着地球发出的光能直接到达地球，它朝其它方向发射的光也可能被附近的黑洞的强引力折射而能到达地球。这样我们不仅能看见这颗恒星的“脸”，还同时看到它的侧面、甚至后背！Rainforest LayersHigh temperature and rainfall production, more or less uniform throughout the year, characterize the rainforest worldwide. The water that is required to maintain this environment also threatens its existence. If left uncontrolled, the water that constantly bombards the soil would leech out most of the valuable nutrients. Plants and animals in this environment have developed adaptations to deal with the constant deluge and to compete successfully for nutrients. The Emergent Layeronkeys, butterflies, insect-eating bats and snakes inhabit this layer, some never venturing below it.The primary layer of the rainforest, the canopy, extends beneath the emergents, rising to 150 feet (45m). Most canopy trees have smooth, oval leaves that come to a point. A possible explanation for this adaptation is that they shed rain quickly, discouraging the growth of lichens and mosses. In cloud forests such as La Selva, the canopy is lower and more dense, formed by smaller trees with twisted crowns of tiny, leathery leaves. At these higher elevations, the leaves have developed a highly reflective property that protects them from the higher levels of intense radiation. This almost solid green shield filters out 80% of the light, preventing its transmission to the forest below.onkeys, sloths, bats, treefrogs, ants, beetles, parrots, hummingbirds and snakes, to mention a few, can be found here, often never touching the ground during their lifetime. Epiphytes, some 28,000 species worldwide, use every tree surface as a place to live. Hollow trunks of trees and pools of water in bromeliads often are micro-communities within the Canopy.This area gets only 2-5% of the sunlight available to the canopy. This limited light encourages the plant residents to devise unique ways to survive, such as the solar-collecting dark green leaves. Plants that survive in the understory include dwarf palms and soft-stalked species of families, such as the ginger family, acanthus and prayer plant or Maranta. These plants seldom grow to more than 12 feet (3.5 m) in height. Understory plants have a more difficult time with pollination because of the lack of air movement. Most rely on insects. Some produce strong smelling flowers, others produce flowers and fruit on their trunks. This phenomenon, known as cauliflory, makes them more conspicuous to aid the process of pollination and seed dispersal. Many animals live here, including snakes, frogs, parakeets, leopards or jaguars and the largest concentration of insects.Almost no plants grow in this region of 0-2% light and 100% humidity. The few flowering plants that live here tolerate deep shade. The floor itself is covered with a litter of rapidly decomposing vegetation and organisms that break down into usable nutrients. A leaf that might take one year to decompose in a temperate climate, will disappear in just six weeks on the rainforest floor. A high proportion of the nutrients in the system are locked in the large biomass (trees and other plant storage systems). There is heavy competition for these nutrients. This is why many trees are so shallow-rooted. Large mammals, such as tapirs, forage for roots and tubers. Insects, including termites, cockroaches, beetles, centipedes, millipedes, scorpions and earthworms, along with the fungi, use the organic litter as a source of food.根据组成：
　　固态的由石头构成的行星：水星，金星，地球和火星：
　　固态行星主要由岩石与金属构成，高密度，自转速度慢，固态表面，没有光环，卫星较少。
　　较大的气态行星：木星，土星，天王星和海王星：
　　气态行星主要由氢和氦构成，密度低，自转速度快，大气层厚，有光环和很多卫星。
　　冥王星。
根据大小:
　　小行星：水星，金星，地球，火星和冥王星。
　　小行星的直径小于13000公里。
　　巨行星：木星，土星，天王星和海王星。
　　巨行星的直径大于48000公里。
　　水星和冥王星有时被称作次行星(lesser planets)（不要与次级行星(minor planets)－－小行星的官方命名－－相混乱）。
　　巨行星有时被称为气态行星。 根据相对地球的位置：
　　地内行星：水星和金星。
　　离太阳与地球较近。
　　地内行星看起来的如同地球上看有时不完整的月亮。
　　地球。
　　地外行星：火星到冥王星。
　　离太阳与地球较远。
　　地外行星看起来通常是完整的，或近乎完整的。 未知点：
　　太阳系是怎样起源的？一般来说是由尘粒与气体的星云压缩形成的，但详情很不清楚。
　　行星系统如何与其它星系共处？已有了木星般大小的在附近轨道运动的对象的恒星的极好的证据。组成固态行星的条件是什幺？看起来地球这样的星体并不是独一无二的，但目前还没有直接证据证明这个或其它。

Glaciers exist where, over a period of years, snow remains after summer’s end. They exist in environments of high and low precipitation and in many temperature regimes; they are found on all the continents except Australia and they span the globe from high altitudes in equatorial regions to the polar ice caps. There is a delicate balance between climatic factors that allows snow to remain beyond its season. … We can best determine the health of a glacier by looking at its mass balance. Each year glaciers yield either a net profit of new snow, a net loss of snow and ice, or their mass may remain in equilibrium. Scientists divide each glacier into upper and lower sections termed the accumulation area, where snowfall exceeds melting during a year; and the ablation area, where melting exceeds snowfall. An equilibrium line, where mass accumulation equals mass loss, separates these areas. You can see it as the boundary between the winter’s snow and the older snow or ice surface. Its altitude changes annually with the glacier’s mass balance. To find mass balance, scientists measure the area of each region and observe amounts of accumulation and ablation relative to preset stakes. After density measurements are made they may calculate how much water has been added or lost to the glacier. … Glaciers have been likened to mighty rivers of ice. Although they move many times more slowly, glaciers have equivalent changes in flow rate and often form falls of fast-moving ice above slow-moving ice pools. Glaciers flow faster down their centers than at ice margins, and more quickly at the surface than at the bed. …

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阅读背景知识

美国和加拿大阅读背景材料 – IDB Internet Explorer

关于美国的历史

The continent’s first inhabitants walked into North America across what is now the Bering Strait from Asia. For the next 20,000 years these pioneering settlers were essentially left alone to develop distinct and dynamic cultures. In the modern US, their descendants include the Pueblo people in what is now New Mexico; Apache in Texas; Navajo in Arizona, Colorado and Utah; Hopi in Arizona; Crow in Montana; Cherokee in North Carolina; and Mohawk and Iroquois in New York State. The Norwegian explorer Leif Eriksson was the first European to reach North America, some 500 years before a disoriented Columbus accidentally discovered ‘Indians’ in Hispaniola (now the Dominican Republic and Haiti) in 1492. By the mid-1550s, much of the Americas had been poked and prodded by a parade of explorers from Spain, Portugal, England and France. The first colonies attracted immigrants looking to get rich quickly and return home, but they were soon followed by migrants whose primary goal was to colonize. The Spanish founded the first permanent European settlement in St Augustine, Florida, in 1565; the French moved in on Maine in 1602, and Jamestown, Virginia, became the first British settlement in 1607. The first Africans arrived as ‘indentured laborers’ with the Brits a year prior to English Puritan pilgrims’ escape of religious persecution. The pilgrims founded a colony at Plymouth Rock, Massachusetts, in 1620 and signed the famous Mayflower Compact – a declaration of self-government that would later be echoed in the Declaration of Independence and the US Constitution. British attempts to assert authority in its 13 North American colonies led to the French and Indian War (1757-63). The British were victorious but were left with a nasty war debt, which they tried to recoup by imposing new taxes. The rallying cry ‘no taxation without representation’ united the colonies, who ceremoniously dumped caffeinated cargo overboard during the Boston Tea Party. Besieged British general Cornwallis surrendered to American commander George Washington five years later at Yorktown, Virginia, in 1781. In the 19th century, America’s mantra was ‘Manifest Destiny.’ A combination of land purchases, diplomacy and outright wars of conquest had by 1850 given the US roughly its present shape. In 1803, Napoleon dumped the entire Great Plains for a pittance, and Spain chipped in with Florida in 1819. The Battle of the Alamo during the 1835 Texan Revolution paved the way for Texan independence from Mexico, and the war with Mexico (1846-48) secured most of the southwest, including California. The systematic annihilation of the buffalo hunted by the Plains Indians, encroachment on their lands, and treaties not worth the paper they were written on led to Native Americans being herded into reservations, deprived of both their livelihoods and their spiritual connection to their land. Nineteenth-century immigration drastically altered the cultural landscape as settlers of predominantly British stock were joined by Central Europeans and Chinese, many attracted by the 1849 gold rush in California. The South remained firmly committed to an agrarian life heavily reliant on African American slave labor. Tensions were on the rise when abolitionist Abraham Lincoln was elected president in 1860. The South seceded from the Union, and the Civil War, by far the bloodiest war in America’s history, began the following year. The North prevailed in 1865, freed the slaves and introduced universal adult male suffrage. Lincoln’s vision for reconstruction, however, died with his assassination. America’s trouncing of the Spaniards in 1898 marked the USA’s ascendancy as a superpower and woke the country out of its isolationist slumber. The US still did its best not to get its feet dirty in WWI’s trenches, but finally capitulated in 1917, sending over a million troops to help sort out the pesky Germans. Postwar celebrations were cut short by Prohibition in 1920, which banned alcohol in the country. The 1929 stock-market crash signaled the start of the Great Depression and eventually brought about Franklin Roosevelt’s New Deal, which sought to lift the country back to prosperity. After the Japanese dropped in uninvited on Pearl Harbor in 1941, the US played a major role in defeating the Axis powers. Atomic bombs dropped on Hiroshima and Nagasaki in 1945 not only ended the war with Japan, but ushered in the nuclear age. The end of WWII segued into the Cold War – a period of great domestic prosperity and a surface uniformity belied by paranoia and betrayal. Politicians like Senator Joe McCarthy took advantage of the climate to fan anticommunist flames, while the USSR and USA stockpiled nuclear weapons and fought wars by proxy in Korea, Africa and Southeast Asia. Tensions between the two countries reached their peak in 1962 during the Cuban Missile Crisis. The 1960s was a decade of profound social change, thanks largely to the Civil Rights movement, Vietnam War protests and the discovery of sex, drugs and rock & roll. The Civil Rights movement gained momentum in 1955 with a bus boycott in Montgomery, Alabama. As a nonviolent mass protest movement, it aimed at breaking down segregation and regaining the vote for disfranchised Southern blacks. The movement peaked in 1963 with Martin Luther King Jr’s ‘I have a dream speech’ in Washington, DC, and the passage of the landmark 1964 Civil Rights Act and 1965 Voting Rights Act. Meanwhile, America’s youth were rejecting the conformity of the previous decade, growing their hair long and smoking lots of dope. ‘Tune in, turn on, drop out’ was the mantra of a generation who protested heavily (and not disinterestedly) against the war in Vietnam. Assassinations of prominent political leaders – John and Robert Kennedy, Malcolm X and Martin Luther King Jr – took a little gloss off the party, and the American troops mired in Vietnam took off the rest. NASA’s moon landing in 1969 did little to restore national pride. In 1974 Richard Nixon became the first US president to resign from office, due to his involvement in the cover-up of the Watergate burglaries, bringing American patriotism to a new low. The 1970s and ’80s were a period of technological advancement and declining industrialism. Self image took a battering at the hands of Iranian Ayatollah Khomeni. A conservative backlash, symbolized by the election and popular two-term presidency of actor Ronald Reagan, sought to put some backbone in the country. The US then concentrated on bullying its poor neighbors in Central America and the Caribbean, meddling in the affairs of El Salvador, Nicaragua, Panama and Grenada. The collapse of the Soviet Bloc’s ‘Evil Empire’ in 1991 left the US as the world’s sole superpower, and the Gulf War in 1992 gave George Bush the opportunity to lead a coalition supposedly representing a ‘new world order’ into battle against Iraq. Domestic matters, such as health reform, gun ownership, drugs, racial tension, gay rights, balancing the budget, the tenacious Whitewater scandal and the Monica Lewinsky ‘Fornigate’ affair tended to overshadow international concerns during the Clinton administration. In a bid to kickstart its then-ailing economy, the USA signed NAFTA, a free-trade agreement with Canada and Mexico, in 1993, invaded Haiti in its role of upholder of democracy in 1994, committed thousands of troops to peacekeeping operations in Bosnia in 1995, hosted the Olympics in 1996 and enjoyed, over the past few years, the fruits of a bull market on Wall St. The 2000 presidential election made history by being the most highly contested race in the nation’s history. The Democratic candidate, Al Gore, secured the majority of the popular vote but lost the election when all of Florida’s electoral college votes went to George W Bush, who was ahead of Gore in that state by only 500 votes. Demands for recounts, a ruling by the Florida Supreme Court in favor of partial recounts, and a handful of lawsuits generated by both parties were brought to a halt when the US Supreme Court split along party lines and ruled that all recounts should cease. After five tumultuous weeks, Bush was declared the winner. The early part of Bush’s presidency saw the US face international tension, with renewed violence in the Middle East, a spy-plane standoff with China and nearly global disapproval of US foreign policy with regard to the environment. On the domestic front, a considerably weakened economy provided challenges for national policymakers. Whether the US can continue to hold onto its dominant position on the world stage and rejuvenate its economy remains to be seen.

美国历史英属北美殖民地的建立（1607–1733）

北美洲原始居民为印第安人。16-18世纪，正在进行资本原始积累的西欧各国相继入侵北美洲。法国人建立了新法兰西(包括圣劳伦斯流域下游大潮区，密西西比河流域等处)；西班牙人建立了新西班牙(包括墨西哥和美国西南部的广大地区)。1607年，英国建立了第1个殖民据点—詹姆士城，此后在大西洋沿岸陆续建立了13个殖民地。到达殖民地的大多数是西欧贫苦的劳动人民，也有贵族、地主、资产阶级，以英国人、爱尔兰人、德意志人和荷兰人最多。移民中有逃避战祸和宗教迫害者，有自愿和非自愿的“契约奴”以及乞丐、罪犯；还有从非洲被贩运来的黑人。

　

“五月花”号 (Mayflower)

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独立战争 （1774—1783）
英法为争夺海上霸权和掠夺殖民地而进行的七年战争，以英国胜利告终。英国在北美接管了加拿大，控制了密西西比河以东的新法兰西，对北美殖民地全面加强控制，宣告阿巴拉契亚山脉以西为王室产业，禁止殖民地人民染指；并征收重税，严厉缉私，限制经济活动，严重损害了殖民地各阶层人民的经济利益。从1619年弗吉尼亚建立议会起，各殖民地相继成立议会，与英国相抗衡，1765年9个殖民地举行抗议印花税大会，掀起反抗怒潮。

18世纪70年代英国进一步执行高压政策，1770年波士顿惨案发生。1773年通过了茶税法，引起波士顿倾茶事件。1774年颁布了5项不可容忍的法令(诸如封闭波士顿港，增派英国驻军，取消马萨诸塞自治权，确立英国对殖民地的司法权等)，从政治上军事上加紧对殖民地的控制与镇压。1772-1774年，各殖民地普遍成立通讯委员会，领导抗英斗争。1774年9月5日，除佐治亚外的各殖民地代表在费城召开了第1届大陆会议，通过了和英国断绝一切贸易关系的决议,继而通过“关于殖民地权利和怨恨的宣言”，向英王呈递请愿书。1775年4月18日，在波士顿附近的列克星敦和康科德，殖民地爱国者打响了反抗的枪声，揭开了独立战争的序幕。5月，第2届大陆会议召开。次年7月大陆会议通过独立宣言，宣布13个殖民地脱离英国独立。

独立战争开始时，双方实力悬殊，战争进行了8年。到1781年10月，美、法联军攻下英军最后据点约克镇，独立战争基本结束。1783年英美签订巴黎和约。独立战争时期涌现出一批杰出的政治家，如大陆军的总司令G．华盛顿、《独立宣言》的起草人T．杰斐逊、外交家B．富兰克林、文化战士T．潘恩。

印花税条例 (Stamp Act)
波士顿惨案 (Boston Massacre)
大陆会议 (Continental Congress)
独立战争 (War of lndependence)
独立宣言 (Declaration of Independence)

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独立的民族主权国家的建成（1781-1814）

在战争过程中，大陆会议制订了邦联条例，1781-1787年13州组成了邦联国会，宣布成立美利坚共和国。1787年，在费城召开制宪会议，大州和小州的代表经过争论，同意每州均选出两名参议员；在蓄奴制问题上，北部对南部作出了重大妥协，默认奴隶制存在，在征税及分配众议员席位方面，南部黑奴均以3／5的人口计算。会议最后制定了宪法草案。这是世界上第1部成文宪法。1788年6月由9个州批准生效。根据宪法，美国建成立法、行政、司法三权分立、相互制衡的联邦制国家。后又增加了宪法前10条修正案(后即以“权利法案”著称)。该法案于1791年12月，经11个州批准生效。

1789年联邦政府成立。4月，华盛顿就任美国首届总统(1792年连任)。在国内外政策出现分歧的过程中，财政部长A．汉密尔顿派组织了联邦党，主张中央集权，外交上亲英，控制了联邦政府的权力。国务卿T．杰斐逊派主张维护国内人民民主权利，同情法国革命，组织了民主共和党。1793年华盛顿在欧洲列强联合干涉法国革命时，采取中立政策。次年11月，联邦政府和英国签订了损害美国主权的杰伊条约。亲英和亲法成为联邦党和民主共和党在外交政策上的分野。在内政方面，联邦政府制定关税条例，建立银行，稳定经济。

1801年，民主共和党T．杰斐逊出任总统。杰斐逊政府废除上述4项法令，削减开支，减轻税收，取消酒税，鼓励农产品出口。1803年从法国手中购买了面积达200多万平方公里的路易斯安那。英国一直不甘心丧失北美殖民地。英舰在公海上继续拦截美国船只，强制征用美国海员。为维护航海自由，1812—1814年美国进行了第2次对英战争。除海战外，优势在英军方面。1814年8月，英军曾攻占华盛顿首府，焚烧总统府及会。但随后美国取得胜利。1814年12月，英美在今比利时的根特签订和约。这次战争使美国得以摆脱英国政治上的控制和经济上的渗透，成为一个完全独立的民族主权国家。

美英巴黎条约 (Treaty of Parise,1783)
美英战争 (1812)(War of l812)

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南北战争前南北经济的不同发展（1814—1861）

19世纪上半叶，美国领土逐渐由大西洋沿岸扩张到太平洋沿岸。经济发生了显著变化，北部、南部经济沿着不同方向发展。北部发展海上贸易，扩大航运业。进行大量的资本原始积累。早在1790年就在罗得岛建立了第l座棉纺厂。此后，陆续出现其他工厂。从19世纪初期起，大量资金投放于工商业，工业生产得到发展。在大力引进西欧科学技术的同时，鼓励创造和发明。50年代，工业化迅速推进。1860年，美国工业生产居世界第4位。2／3的制造品由东北部生产。西欧移民大批涌入，并向西迁移，为发展经济提供了自由雇佣劳动力。但在南部，以奴隶劳动为基础的棉花种植园经济不断扩大，由大西洋沿岸各州扩展到得克萨斯境内。在西部新开辟的地区，是推广自由劳动制还是奴隶制，南部和北部的代言人争执不休，成为全国政治斗争的主题。1820年北部对南部作出让步，达成《密苏里妥协案》，双方争执暂时乎息。

西进运动 (Westwood Movement)
密苏里妥协案 (Missouri Compromise)
南北战争前的外交和政治 （1814—1861）

1823年，美国总统J．门罗发表了“门罗宣言”。反对欧洲列强干涉西半球事务。1846-1848年，美国发动对墨西哥战争，把得克萨斯、新墨西哥和加利福尼亚并入美国领土。1814年美英战争即将结束时，联邦党召集哈特福德会议，图谋分裂联邦，但遭失败，因而瓦解。联邦党的衰落标志着商业资本开始向工业资本过渡。1816-1824年，美国进入民主共和党一党执政时期，它代表北部资产阶级和南部奴隶主的共同利益，习称“和谐时期”。以后民主共和党分裂，政治力量重新组合。1828年，成立了民主党，推选A．杰克逊为总统候选人，杰克逊当选并连任总统至1837年3月。1834年辉格党成立。杰克逊政府将印第安人迁至密西西比河以西，并制止了南卡罗来纳州借口高关税法而掀起的分裂危机。政府废除了贫民因负债而受监禁的法令，普及了白人男子的普选权，并进行了一些民主改革，习称“杰克逊民主”。1828-1856年，民主党和辉格党成为对峙的两大政党。除1840年和1848年两届总统竞选由辉格党获胜外，其余各届总统竞选均由民主党获胜。

随着南部和北部两种不同社会经济制度斗争的激化和黑奴反抗的不断掀起，群众性的反奴运动广泛开展。1840年，主张废奴运动的“自由党”成立。1848年，废奴主义者，民主党和辉格党内反对奴隶制的人组织了自由土壤党，以在西部地域建立自由州为宗旨。1850年，双方经过争执，达成妥协，国会通过严峻的逃奴追缉法。1854年国会通过堪萨斯—内布拉斯加法案，取消了奴隶州和自由州的地理疆界线，也就使密苏里妥协案随之废除，遭到北部工业资产阶级的强烈反对。1854年成立了共和党，以反对奴隶制为宗旨。1856年。民主党J．布坎南当选总统，此时实际上民主党已成为代表奴隶主利益的政党。1857年最高法院作出斯科特判决案，其法律涵意是使奴隶制的规模推向全国。1859年J．布朗领导的反奴隶制的武装起义被镇压。1860年总统选举中，共和党候选人A．林肯获胜。蓄谋叛乱已久的南部奴隶主集团决定脱离联邦，并于1861年2月另行成立宣布维护奴隶制的南部同盟。

门罗主义 (Monron Doctrine)
废奴运动 (Abolition Movement)
堪萨斯—内布拉斯加法案 (Kansas-Nebraska Act)
约翰·布朗起义 (John Brown’s Rebellion)
　
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南北战争及重建时期（1861-1877）

1861年4月，南部同盟不宣而战，占领萨姆特炮台，南北战争爆发。次年5月，林肯颁布《宅地法》，允许耕种西部土地5年的农民，在缴纳10美元证件费后获得160英亩土地的使用权，使在西部垦殖的广大农民，站在废奴派一边，孤立了南部同盟。1863年1月1日，林肯颁布的《解放宣言》生效，叛乱各州的黑人奴隶都被视为自由人，允许参军，短期内即有18．6万名黑人参加联邦军队。1864年联邦军队占领佐治亚的亚特兰大，将南部同盟截成两段，取得了决定的胜利。1865年4月9日，南部同盟军总司令R．E．李将军投降。南北战争以联邦胜利宣告结束。4月14日；林肯遇刺，副总统A．约翰逊继任总统。约翰逊对南部种植园主推行妥协政策。11月，密西西比州首先颁布“黑人法典”，对黑人残酷迫害。恐怖组织三K党于1866年成立，对刚获得自由的黑人施以私刑。在这种混乱局面下，共和党激进派占优势的国会提出弹劾总统案(以少1票未通过)，并分别于1865、1868和1870年通过了宪法第13条修正案(宣布在美国奴隶制不复存在)、第14条修正案(黑人被承认为美国公民)、第15条修正案(给黑人以选举权)。1867年3月，国会通过重新建设南部法案，对南部实行军管。1867-1877年，南部进行民主重建，各州成立了黑人和白人联合执政的政权，制订了民主的进步法令，14名黑人当选为众议员，两名黑人当选为参议员。R.B.海斯就任总统，标志着民主重建的结束。

南北战争 (CivilWar)
宅地法 (Homestead Act)
解放宣言 (Emancipation Proclamation)
重建时期 (Reconstruction)
　
=========================

19世纪后半叶经济迅速发展 (1877—1900）

南北战争后，由于南部种植园制度的废除，为资本主义在全国范围的发展创造了条件；造船业和机器制造业迅速发展，横贯大陆的4条铁路建成，西部广大土地的垦殖，边疆的消失，促进了国内统一市场的形成和扩大。在中西部、远西部和南部日益开拓进程中，各地区发展了具有本地特点的工业。外国移民的大量涌入，提供了丰富的劳动力，使北美能够大规模进行农业生产。19世纪后半叶农业机械化迅速发展。从1860-1916年，耕地面积由4．07亿英亩增加到8．79亿英亩，改良的土地面积扩大了3倍多，小麦和玉米的产量约增加了3倍多。农业中大生产排挤和兼并小生产，在以工业为主的北部，农业日益采用集约耕作，在其他地区，大农场数字逐渐增加，1900年美国农产品总数的一半是由1／6的大农户生产的，形成了美国式农业资本主义发展道路。

19世纪后半叶，科学技术领域有重要发明和突破，其中首推电力的应用；1876年A．G：贝尔发明电话机，1886年T．A．爱迪生制造了电灯，1892年杜里雅兄弟试制成功汽车，1903年莱特兄弟试制飞机航行成功。电力广泛应用于工业，导致美国经济的全面发展。1880年工业在全国生产总值中的比重已超过农业，工业生产总值由1860年的世界第4位，跃居至1894年的首位。美国成为高度发达的资本主义国家。

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第一次世界大战前的内外政策（1889—1914）

1889年美国召开泛美会议，1898年美西战争爆发，美国击败了西班牙，夺取了加勒比海的古巴和波多黎各、太平洋的关岛及菲律宾群岛，接着合并了夏威夷群岛。1903年美国夺取了巴拿马运河区。在远东，1899年美国提出对华“门户开放”政策。美国在1904-1905年日俄战争中支持日本。在日俄战争结束后，美日双方经过谈判，于1908年签订了罗脱—高平协定。在1912年总统选举中，民主党总统候选人T．W．威尔逊上台。威尔逊以“新自由”作为号召进行改革，降低关税，建立联邦储备银行制度，通过克莱顿反托拉斯法(1914)，征收累进所得税。该时期美国在对外政策上，对西半球墨西哥、尼加拉瓜等国进行了武装干涉。

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第一次世界大战至20世纪20年代末的美国

第一次世界大战开始后，美国宣布中立，向交战双方提供军火，不久又对协约国进行贷款。1916年，威尔逊当选连任。1917年，美国在德国潜艇击沉美国船只后，于4月6日对德宣战。大战期间由于国外移民中断，黑人大量北移，并人伍出国作战，开拓了视野。1918年11月，威尔逊签署对德停战协定。第一次世界大战促进了美国的经济繁荣。战后，美国由欠60亿美元的债务国而成为贷出100亿美元的债权国，美国成为最富有的国家。1921年共和党W．G．哈定执政，正值美国陷入全面经济萧条。他提出“工业正常化”和”抢救资本主义”政策；1923-1929年世界资本主义进人相对稳定时期。美国国内由于固定资本更新，建筑业兴起，汽车和钢铁工业等扩大以及商品和资本输出激增，1923年美国工商业出现了新高涨。与此同时，美国第2次企业“合并浪潮”(即进一步托拉斯化)，遍及银行业、工业部门，特别是水、电、煤气公用事业，甚至扩展到零售商业部门。共和党人C，柯立芝执政时期是美国经济繁荣时期。私人垄断资本大为发展。但由于国内新兴工业畸形发展与生产过剩，使国民经济各部门比例严重失调，生产和消费脱节，农业长期陷于慢性危机，1929年10月美国首先爆发经济危机，随后资本主义各国陆续陷入1929-1933年世界性经济危机。

大萧条 （Great Depression)

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20世纪30年代的美国

民主党人F.D．罗斯福1933年就任第32届总统。罗斯福政府实行了由国家对经济进行广泛干预、调节的“新政”，整顿金融，复兴工农业，举办救济事业等，挽救了美国的严重经济危机，并加强了国家垄断资本主义。1933年11月，美国与苏联建交，对拉丁美洲采取“睦邻政策”。1937年新的经济危机再度出现。次年，罗斯福采用扩大赤字开支的办法，使这次危机有所缓解；第二次世界大战爆发后，美国重振军备，才使经济得到恢复，走向繁荣。

新政 （New Deal）
睦邻政策 （Good Neighbor Policy）

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第二次世界大战期间的美国

1939年9月德国进攻波兰，第二次世界大战全面爆发。罗斯福于1941年3月签署《租借法》，向与德意日作战的国家提供物资。8月14日，罗斯福与英国首相丘吉尔发表《大西洋宪章》，9月24日苏联政府声明同意其基本原则，接着召开莫斯科三国会议，奠定了美英苏战时合作的基础。12月7日，日本偷袭珍珠港，重创美国太平洋舰队。次日，美英对日宣战。英美在开始时接连败退。1942年5月，美军在中途岛海战中击退日军。同年底至次年初，美国在瓜达尔卡纳尔岛战役中击败日军，美军由守势转为攻势，太平洋战争出现转折。 l942年1月1日，美、英、苏、中等26个国家签署《联合国家宣言》。8月英美联军在北非登陆。1943年2月斯大林格勒战役的胜利，使欧洲反法西斯战争的局势发生根本性变化。同年7月，美英军队在西西里岛登陆。9月在意大利南部登陆。10月意大利投降。1943年 11月，罗斯福、丘吉尔、斯大林举行德黑兰会议。1944年6月，英美等国的联军在法国诺曼底登陆，开辟了欧洲第二战场。4月12日，罗斯福逝世，H．S．杜鲁门继任总统。5月，德国宣布无条件投降。7月，美英苏三国首脑举行波茨坦会议，美英就处理德国、波兰等问题与苏联达成协议。美英中发表了波茨坦公告，要求日本无条件投降。美苏就苏军对日作战取得了一致意见。8月6日，美军在广岛投下策1颗原子弹；8月8日苏联宣布对日作战，9日美军又在长崎投下第2颗原子弹，日本投降，第二次世界大战结束。杜鲁门任命D．麦克阿瑟为盟国驻日最高统帅，美军进驻日本，实现了由美国独家控制日本的局面。

大西洋宪章 (Atlantic Charter)
开罗会议 (Cairo Conference)
德黑兰会议 (Teheran Conference)
雅尔塔会议 (Yalta Conference)
波茨坦会议 (Potsdame Conferenc)

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第二次世界大战后的美国

第二次世界大战中，由于扩军参战，并大量供应盟国军火物资，美国成为盟国的兵工厂，出现了战时经济繁荣，国家垄断资本有更大发展。美国利用参战的机会，控制了世界许多重要战略据点，建立了军事基地；杜鲁门政府对外推行冷战政策，提出杜鲁门主义，制订马歇尔计划，筹划成立了北大西洋公约组织。

在内政方面，杜鲁门提出“公平施政”纲领，但收效甚微。1950年6月，朝鲜战争爆发。1952年共和党人D．D．艾森豪威尔以结束朝鲜战争的许诺当选为美国总统。1953年7月签定了朝鲜停战协定。

艾森豪威尔政府在1953-1954年经济危机的侵袭下，为缓和国内外紧张形势，在内政外交方面作了调整，扩大了社会保险法的实施范围，加强科研工作的国家化，进一步发展宇航事业。1955年7月美、英、法、苏四国首脑会议召开，国际形势有所缓和。1957年苏联成功地发射第1颗人造地球卫星，向美国尖端科学领先地位进行挑战。1958年，美国发射人造地球卫星，从而使美苏军备竞赛进入宇宙空间竞争。1969年7月20日，美国宇宙飞船“阿波罗—11”号登月舱在月球着陆。

在第二次世界大战及朝鲜战争期间，由于有黑人参加作战，军队中取消了种族隔离制度，这一事实推动了国内黑人争取民权的斗争。1954年最高法院作出“布朗控诉教育局判决案”，宣布长期统治教育领域的“隔离但平等”原则为违宪。1955年12月，亚拉巴马州蒙哥马利市的黑人在M．L．金的领导下，进行长达381天的抵制乘车方面种族隔离的运动，黑人又在餐馆展开静坐运动，以抗议这方面的种族隔离，民权运动蓬勃兴起。60年代民主党J．F．肯尼迪和L．B．约翰逊相继执政，实行长期财政赤字政策，扩大军费开支，增加福利费用，经济持续上升。同时，由于他们卷入越南战争，支付巨额军费，消耗了美国大量财富，使美国经济实力大为削弱，而联邦德国和日本经济迅速发展，逐渐成为美国的竞争对手。

60年代，由于越南战争不得人心，国内社会动荡不宁。1961年黑人和白人公民共同展开“自由乘客”运动，1963年4月，小马丁·路德·金在伯明翰发动了大规模游行、请愿、静坐和示威运动，8月，25万黑人和白人一起为抗议种族歧视，举行了向华盛顿的进军示威，小马丁 路德·金发表了“我有一个梦”的演说。在黑人民权运动的推动下，国会于1964年6月通过民权法。

1969年R．M．尼克松上台后，美国陷入越战泥淖不能自拔，经常性的财政赤字和庞大的军费开支，加剧了通货膨胀，处于内外交困境地。1969年起，尼克松以“伙伴关系、实力加谈判”作为美国对外政策的新战略。1972年尼克松总统访华，发表了中美上海公报。1974年8月9日，尼克松因水门事件被迫辞职，副总统G．R．福特即就任第38届总统。1975年5月，正式宣布越南战争结束。

1979年1月1日中美建交公报生效，实现了两国关系正常化。在美苏关系方面，尼克松提出新“和平”战略后，两国加强了对话。1972年5月，尼克松访苏，签署了限制战略武器条约。80年代，美苏军备竞赛从数量方面转向质量方面。1985年以来，美苏经过不断谈判，终于在1988年6月1日，两国领导人在莫斯科交换了中程导弹条约的批准书。美苏关系进一步趋向缓和。

1986年11月，美国爆发了“伊朗门”事件，披露里根政府(成员)绕过国务院并隐瞒国会，于1985年至1986年秘密向伊朗出售武器，以换取美国人质，并将其中所得款项，转移给尼加拉瓜反政府武装。1987年，美国以保护海湾通航的名义，派遣军事力量去海湾，同伊朗多次发生军事冲突。1989年1月布什就任美国第41届总统。

1990年爆发海湾战争。美国出兵伊拉克。迫使其退出科威特。1992年，民主党人克林顿当选总统。其间美国及多国部队多次空袭伊拉克以制止其研制核武器。90年代末，在美国领导下，北约东扩。

1999年初，美国领导北约向南联盟发动空中打击。

在经济方面，1973年“能源危机”后，1974-1975年美国爆发了战后最严重的经济危机；美国经济陷于以“滞胀”为特征的综合并发症中；1980年美国经济严重衰退。1981年里根任总统后，推行高赤字财政政策，用大规模减税和增加国防开支来刺激经济、鼓励投资，同时严格控制货币发行量。1982年美国经济开始复苏，转入低速增长。1987年10月虽发生股市暴跌风潮，美国经济情况仍较平稳，但财政赤字和外贸赤字仍是美国经济的隐忧。进入90年代，美国计算机产业发展迅速，并带动全球的高科技信息产业，开拓了新一代的产业革命！

杜鲁门主义 (Truman Doctrine)
马歇尔计划 (Marshall Plan)
共同安全法 (Mutual Security Acts)
古巴导弹危机 (Cuban Missile Crisis)
尼克松主义 (Nixon Doctrine)

The American Revolution
The War of Revolution between America and Britain began in April 1775 in *Lexington, Massachusetts, when soldiers from each side met and somebody fired a shot. It was called the ‘shot heard round the world’ because the war that followed changed the future of the *British Empire and America. But the American Revolution, the movement to make an independent nation, began many years earlier.

The causes of revolutionThe desire of Americans to be independent from Britain arose out of a long series of disagreements about money and political control. Britain had had colonies (= places taken over by people from a foreign country) in North America since 1607 and kept soldiers there to defend them from attack by the French and Spanish, and by *Native Americans. In order to raise money for this, the British *Parliament tried to make the colonists (= people who had gone to settle in America) pay taxes.
From 1651, Britain passed a series of laws called Navigation Acts, which said that the colonists should trade only with Britain. These laws were frequently broken and were a continuing source of tension. Taxes imposed in the 18th century increased ill feeling towards Britain. In 1764 the Sugar Act made colonists pay tax on sugar, and in 1765 the *Stamp Act put a tax on newspapers and official documents. Opposition to this was strong and the following year Parliament had to remove the tax. By then, people in both America and Britain were arguing about who had the power to tax the colonies. The 13 colonies each had an assembly of elected representatives, and the colonists wanted these assemblies to decide what taxes they should pay, not Parliament. Some colonists, called patriots, began to want independence from Britain. They expressed their feelings in the slogan ‘no taxation without representation’.
In 1767 there was a disagreement in New York about whether Britain could ask people to give soldiers accommodation in their houses. The local assembly agreed, eventually, but became involved in a dispute with Parliament over who had the right to decide such matters. In the same year the Townshend Acts put taxes on certain products including tea. The assemblies refused to help collect the money and Parliament responded by closing them down. All this caused many more people to want independence. *Boston, especially, had many patriots, including those who called themselves the *Sons of Liberty. On 5 March 1770 there was a riot in Boston and British soldiers killed five people. This incident became known as the *Boston Massacre.
The Tea Act gave a British company the right to sell tea to the colonists and actually lowered the price for legally imported tea. But most colonists bought cheaper tea that had been smuggled into the country. On 16 December 1773, when ships arrived in Boston Harbour carrying the tea, a group of patriots dressed up as Native Americans went onto the ships and threw the tea into the water. After the *Boston Tea Party, as the event was later called, Britain passed the Intolerable Acts, laws to increase her control over the colonies.
As more Americans began to support revolution, Britain sent yet more soldiers. On 5 September 1774 representatives of all the colonies except *Georgia met in *Philadelphia, calling themselves the *Continental Congress. The Congress decided that the colonies needed soldiers of their own, and agreed to start training militiamen who could leave their jobs and be used as soldiers if necessary. Since the militiamen had to be ready to fight at short notice, they were called *minutemen.
On 18 April 1775 British soldiers marched out of Boston into the countryside to search for weapons that the colonists had hidden. Paul *Revere, a patriot from Boston, rode ahead to warn people that the British were coming. The minutemen got ready, and when they and the British met, the ‘shot heard round the world’ was fired.
The Revolutionary War
The Americans had the advantage of fighting at home, but Britain was a much stronger military power. There were victories and defeats on both sides during the seven years of war.
The first aim of the American army led by George *Washington was to force the British, called *Redcoats because of the colour of their uniform, to leave Boston. On 17 June 1775 the British fought and won the Battle of *Bunker Hill, but they lost so many soldiers that their position in Boston was weak and in March 1776 they were forced to leave. The Continental Congress suggested that Britain and America should make an agreement, but Britain refused and so, on 4 July 1776, members of the Congress signed the *Declaration of Independence. This document, written by the future President Thomas *Jefferson, gave the Americans’ reasons for wanting to be independent. It included ideas that were rather new, e.g. that ordinary people had certain rights that governments should respect. Since the British king *George III refused to accept this, Americans had the right, and the duty, to form their own government.
Later in the same year the British took control of *New York and *Rhode Island, and Washington’s army moved away into *Pennsylvania. The defeats discouraged many Americans, but at Christmas, when soldiers were not expecting an attack, Washington surprised the British by taking his army across the Delaware River to Trenton, *New Jersey, and defeating the Hessians, German soldiers paid by the British to fight for them. A story often told is that, before crossing the river, Washington threw down a silver dollar, thinking that if any guards were near they would hear the noise and come. Since nobody came, he knew it was safe to attack.
Washington’s army spent the winter at *Valley Forge, Pennsylvania. It was very cold and the new government of the United States did not have money to provide soldiers with warm clothes and food. Many became ill, and many more lost their enthusiasm for the war. But in the spring of 1777 they received help from two different sources. A German, General von Steuben, came to train the American soldiers, and the Marquis de *Lafayette brought French soldiers to fight on the American side. With this help, the Americans won a victory at *Saratoga, New York. France and also Spain supported the United States because they thought that if Britain became weaker in North America, it would also be weaker in Europe.
Over the next few years, neither side was strong enough to defeat the other completely. But in 1781 Washington saw a perfect opportunity to win. The British General *Cornwallis had taken his army to *Yorktown, Virginia, where he was too far away to get supplies or help. Washington marched south to meet him, while French ships made sure that the British could not receive help by sea. Cornwallis realized how bad his position was and surrendered.
In 1783, after a period of talks, Britain recognized the United States of America, making the US completely independent and giving it the western parts of North America.
Modern American attitudes to the Revolution
The Revolution is remembered by Americans in many ways. *Freedom, and the right of ordinary people to take part in their own government, the main reasons why Americans fought the War of Revolution, are values that almost all Americans still support strongly. The *Fourth of July, the day on which the Declaration of Independence was signed, is a national holiday, *Independence Day.
Places, like Boston Harbour and *Independence Hall in Philadelphia, where the Declaration of Independence was signed, are visited by millions of Americans every year. The names of people involved in the Revolution are known to everyone. George Washington’s birthday is celebrated as a national holiday. John *Hancock’s signature on the Declaration of Independence was the largest, so today John Hancock means ‘signature’. Patrick *Henry is remembered for his speeches, especially for saying, ‘Give me liberty or give me death’.
But if Americans remember the Revolution as a great victory, they seem to forget that the British were the enemy. The governments and people of the two countries have always had a special relationship, and for many Americans, even those whose ancestors were not British, Britain is still the ‘mother country’.

The Civil WarCauses of the war
The American Civil War was fought between the northern and southern states from 1861 to 1865. There were two main causes of the war. The first was the issue of *slavery: should Africans who had been brought by force to the US be used as slaves. The second was the issue of states’ rights: should the US federal government be more powerful than the governments of individual states.
The North and South were very different in character. The economy of the South was based on agriculture, especially cotton. Picking cotton was hard work, and the South depended on slaves for this. The North was more industrial, with a larger population and greater wealth. Slavery, and opposition to it, had existed since before independence (1776) but, in the 19th century, the abolitionists, people who wanted to make slavery illegal, gradually increased in number. The South’s attitude was that each state had the right to make any law it wanted, and if southern states wanted slavery, the US government could not prevent it. Many southerners became secessionists, believing that southern states should secede from the Union (= become independent from the US).
In 1860, Abraham *Lincoln was elected President. He and his party, the *Republicans, were against slavery, but said that they would not end it. The southern states did not believe this, and began to leave the Union. In 1860 there were 34 states in the US. Eleven of them (South Carolina, Mississippi, Florida, Alabama, Georgia, Louisiana, Texas, Virginia, Arkansas, Tennessee and North Carolina) left the Union and formed the *Confederate States of America, often called the Confederacy. Jefferson *Davis became its President, and for most of the war *Richmond, Virginia, was the capital.

Four years of fightingThe US government did not want a war but, on 12 April 1861, the Confederate Army attacked *Fort Sumter, which was in the Confederate state of South Carolina but still occupied by the Union army. President Lincoln could not ignore the attack and so the Civil War began.
Over the next four years the Union army tried to take control of the South. The battles that followed, *Shiloh, Antietam, *Bull Run and Chicamauga, have become part of America’s national memory. After the battle of *Gettysburg in 1863, in a speech known as the *Gettysburg Address, President Lincoln said that the North was fighting the war to keep the Union together so that ‘…government of the people, by the people, for the people, shall not perish from the earth’. In the same year he issued the *Emancipation Proclamation which made slavery illegal, but only in the Confederacy.
Slaves and former slaves played an important part in the war. Some gave information to Union soldiers, because they knew that their best chance of freedom was for the North to win the war. Many former slaves wanted to become Union soldiers, but this was not very popular among white northerners. In spite of this opposition about 185000 former slaves served in the Union army.
Women on both sides worked as spies, taking information, and sometimes even people, across borders by hiding them under their large skirts.
In the South especially, people suffered greatly and had little to eat. On 9 April 1865, when the South could fight no more, General Robert E *Lee surrendered to General Ulysses S *Grant at *Appomattox Court House in Virginia. A total of 620000 people had been killed and many more wounded.
The war was over but feelings of hostility against the North remained strong. John Wilkes *Booth, an actor who supported the South, decided to kill President Lincoln. On 14 April 1865 he approached the President in Ford’s Theatre in Washington and shot him. Lincoln died the next morning.
The killing of President Lincoln showed how bitter many people felt. The South had been beaten, but its people had not changed their opinions about slavery or about states’ rights. During the war, the differences between North and South had become even greater. The North had become richer. In the South, cities had been destroyed and the economy ruined.
Reconstruction
After the war the South became part of the United States again. This long, difficult period was called Reconstruction. The issues that had caused the war, slavery and states’ rights, still had to be dealt with. The issue of slavery was difficult, because many people even in the North had prejudices against Blacks. The new state governments in the South wanted to make laws limiting the rights of Blacks, and the US government tried to stop them. Between 1865 and 1870 the 13th, 14th and 15th *Amendments to the *Constitution were passed, giving Blacks freedom, making them citizens of the US and the state where they lived, and giving them, in theory, the same rights as white Americans.
Many northern politicians went to the South where they thought they could get power easily. These northerners were called *carpet-baggers. Both carpet-baggers and southern politicians were dishonest and stole money from the new governments, which hurt the South even more.
In 1870 the last three southern states were admitted to the Union again, and in 1877 the northern army finally left the South. The war lasted four years, but efforts to reunite the country took three times as long.

Effects of the Civil War
Differences between North and South are still strong. In the South the Confederate flag is still often used, and the state flags of *Georgia and *Mississippi were made to look similar to it. The state motto is Audemus jura nostra defendere, which is Latin for ‘We dare to defend our rights’. The Civil War helped to end slavery, but long afterwards Blacks were still being treated badly, and race relations continue to be a problem. The South was so angry with the *Republicans, the party of Lincoln and Reconstruction, that southerners voted *Democratic for a century. The war showed strong differences between parts of the US, but many people believe that the most important thing it did was to prove that the US is one country.

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微生物背景材料细菌：细菌分三类：种类最多的杆菌（一般1-10微米）；数目众多的球菌（一般1微米）以及纤细活泼的螺旋菌（见照片，一般长10-20微米，直径0.1-0.2微米）。此外还分：靠化学反应合成有机物的化能合成细菌和靠光合作用生产有机物的光合自养菌，如蓝藻菌；以它们合成的有机物为营养来源的异养细菌。还有厌氧细菌；好氧细菌和兼性细菌。还有寄生细菌等等。真菌(fungus)真菌与细菌的主要区别在于:真菌是真核生物,而细菌是原核生物。真菌比细菌大,一般放大500倍左右就可以看清。真菌细胞内有线粒体,高尔基复合体,内质网等细胞器,而细菌没有。真菌的核蛋白体沉降系数为80s,而细菌为70s。真菌与植物的主要区别在于:真菌贮藏的养料是肝糖,而绿色植物主要是淀粉。病毒病毒的一级分类：DNA病毒；RNA病毒。二级分类：动物病毒；植物病毒；细菌病毒。病毒的繁殖：病毒是专性活细胞内寄生物。它不能单独进行繁殖，必须在活细胞内才能繁殖。它的增殖方式称为复制，整个复制过程称为复制周期。概括起来分为：吸附，侵入，脱壳，生物合成，装配与释放等5个步骤。 吸附：病毒粒子借衣壳上的受体与宿主细胞“粘附”在一起，否则，病毒粒子将不能侵入宿主细胞。生物合成、装配与释放：病毒的核酸在细胞内借助于宿主细胞的蛋白质合成系统和酶系统不断的复制自己的各种组成成分。当到达一定的数量以后，会组成新的病毒粒子。以各种方式释放出来。有的是使宿主细胞破裂死亡，使病毒粒子释放出来；有的以出芽的方式从细胞上“长”出来，比如流感病毒… Dust Bowl
Dust Bowl, common name applied to a large area in the southern part of the Great Plains region of the United States, much of which suffered extensively from wind erosion during the 1930s. The area included parts of Kansas, Oklahoma, Texas, New Mexico, and Colorado. In its original state, the region was covered with hardy grasses that held the fine-grained soil in place in spite of the long recurrent droughts and occasional torrential rains characteristic of the area. A large number of homesteaders settled in the region in the 30 years before World War I, planting wheat and row crops and raising cattle. Both of these land uses left the soil exposed to the danger of erosion by the winds that constantly sweep over the gently rolling land. Beginning in the early 1930s, the region suffered a period of severe droughts, and the soil began to blow away. The organic matter, clay, and silt in the soil were carried great distances by the winds, in some cases darkening the sky as far as the Atlantic coast, and sand and heavier materials drifted against houses, fences, and barns. In many places 8 to 10 cm (3 to 4 in) of topsoil were blown away. Many thousands of families, their farms ruined, migrated westward; about a third of the remaining families had to accept government relief.补充：由于dust bowl导致的洛杉矶地区的移民增加
In the 1930s and 1940s, the region also received two waves of major migrations: that of farm families from the southern Great Plains migrating west to escape the Dust Bowl, and that of African Americans moving out of the American South. During World War II (1939-1945) the need for labor, especially in ship and aircraft production, boosted the population even more. The population of Los Angeles County jumped from 3 million to 4.7 million between 1940 and 1950.

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美国文学简史美国文学的历史不长，它几乎是和美国自由资本主义同时出现，较少受到封建贵族文化的束缚。美国早期人口稀少，有大片未开发的土地，为个人理想的实现提供了很大的可能性。美国人民富于民主自由精神，个人主义、个性解放的观念较为强烈，这在文学中有突出的反映。美国又是一个多民族的国家，移民不断涌入，各自带来了本民族的文化，这决定了美国文学风格的多样性和庞杂性。美国文学发展的过程就是不断吸取、融化各民族文学特点的过程。许多美国作家来自社会下层，这使得美国文学生活气息和平民色彩都比较浓厚，总的特点是开朗、豪放。内容庞杂与色彩鲜明是美国文学的另一特点。个性自由与自我克制、清教主义与实用主义、激进与反动、反叛和顺从、高雅与庸俗、高级趣味与低级趣味、深刻与肤浅、积极进取与玩世不恭、明快与晦涩、犀利的讽刺与阴郁的幽默、精心雕琢与粗制滥造、对人类命运的思考和探索与对**的病态追求等倾向，不仅可以同时并存，而且形成强烈的对照。从来没有一种潮流或倾向能够在一个时期内一统美国文学的天下。美国作家敏感、好奇，往往是一个浪潮未落，另一浪潮又起。作家们永远处在探索和试验的过程之中。20世纪以来，许多文学潮流起源于美国，给世界文学同时带来积极的与消极的影响。殖民地时期 美国民族文学形成于独立革命时期。这场斗争产生大量的革命诗歌，并且造就了美国头一批重要的散文家和诗人。政治上的独立促进文化上的独立。战争结束之后，美国作家的作品陆续增多，逐渐摆脱英国文学的垄断局面。年轻的民主共和国使人们满怀信心，并吸引着旧世界更多的人们奔向新的大陆。这样的社会条件促使19世纪上半叶的文学创作具有浪漫主义的色彩。作家们吸取欧洲浪漫派文学的精神，对美国的历史、传说和现实生活进行描绘，美利坚民族内容逐渐丰富和充实起来。从20、30年代到南北战争前夕，是浪漫主义运动的全盛时期，各种不同风格的作家泉涌而出，作品从内容到形式都具有鲜明的民族特色。批评家们称这一时期为美国文学“第一次繁荣”。到了世纪中叶，浪漫主义文学的基调由乐观走向疑虑，迫切的社会矛盾，如蓄奴制，又使某些作家采取现实主义的创作方法。 民族文学的诞生 下，已经具有民族独立的意识。富兰克林世俗的格言比爱德华兹清教，主义的教诲更能吸引广大群众。富兰克林用清晰、幽默的文体传播了科学文化，激发自力更生的精神，他的爱国热情和关于自学、创业的言论，对于美国人民的人生观、事业观和道德观产生了深远的影响。独立革命期间充满反抗与妥协之间的尖锐斗争，迫使作家们采取政论、演讲、散文等简便而又犀利的形式投入战斗。发表“不自由毋宁死”这一名言的演说家舶特里克·亨利，象战鼓那样鼓动战士奋勇杀敌的托马斯·潘恩，行文朴质无华却字字击中要害的托马斯·杰斐逊，都是无畏的战士，他们为了战斗的需要锤炼自己的语言艺术。那个时期的诗歌也具有强烈 19世纪初，一些以美国为背景、美国人为主人公的作品开始出现，初具美利坚民族的特色。欧文致力 19世纪30年代以后，东北部沿海的美国文化中心新英格兰地区成了最早的工业区。杰克逊总统的民主主义路线又使国内的民主空气增涨。这在意识形态上造成两方面的后果：一方面出现了超验主义者团体，另一方面使一些作家产生不少疑虑，浪漫主义文学的基调由乐观转向怀疑和消极。超验主义是一场思想解放运动，先表现为宗教，哲学思想中的改革，后扩展到文学创作领域。以爱默生为首的超验主义者为了据弃加尔文教派“以神为中心”的思想，吸取康德先验论和欧洲浪漫派理论家的思想材料，提出人凭直觉认识真理，因而在一定范围内人就是上帝。这一派思想的出发点是人文主义，即强调入的价值，反对权威，祟尚直觉，主张个性解放，打破神学和外国教条的束缚，对美国作家产生不小的影响。到了50年代，随着工业化引起的种种社会问题的出现，作家们敏锐地感受到民主制的弊病。梭罗侧重超验主义中人的“自助”精神，主张回返自然，保持纯真的人性，因此与资产阶级社会秩序发生冲突。在霍桑与梅尔维尔身上，这种矛盾以抽象、神秘的形式表现出来。霍桑深受加尔文教派的影响，又想有所摆脱，于是转向对人类状况与命运的探索，如《红字》(1850)。梅尔维尔同霍桑一样，把他所感觉到的社会矛盾归结为抽象的“恶”，而“恶”的强大与不可理解使《白鲸》(1851)等作品蒙上神秘、悲观的气氛。 “婆罗门” 尔(1819－1891)和霍姆斯(1809－1894)都是知识界的名流。他们出于资产阶级民主主义和人道主义，歌颂爱国主义精神，反对蓄奴制，同情印第安人，也对社会流弊提出一些批评。由于他们的出身地位和文化教养，他们的观点和情绪一般较为温和。废奴文学19世纪30年代之后，北部进步人士掀起越来越高涨的废除黑奴运动。黑人的处境激起许多作家的同情，从爱默生、朗费罗到惠特曼都写过反对蓄奴的诗篇。影响最大的作品是斯托夫人的小说《汤姆叔叔的小屋》(1852)，林肯称她为“发动了一次战争的小妇人”。诗人惠蒂埃抗议蓄奴制的诗篇数量最多，反映了19世纪废奴运动历次重大的斗争。废奴文学虽限于道义上的谴责，却推动了废奴斗争，在文学史上也是19世纪现实主义创作的先声。 伟大的民主诗人怠特曼 　
南北战争到第一次世界大战 乡土文学最先出现于19世纪20、30年代，南北战争后进一步发展。这种文学描绘本乡本土的传说与现实生活，地方色彩浓厚，基调是乐观的、抒情的，如描写西部矿工生活的布雷特·哈特(1836－1902)，或者是幽默的、机智的，如裘维特(1849－1909)，这是战后美国健康、活泼生活情趣的反映。马克。吐温的创作活动持续近50年，是这时期主要的作家，代表作是《哈克贝里·费思历险记》(1884)。他早期的短篇小说吸取西部乡土文学中幽默故事的特点，采用诙谐、滑稽的夸张手法表现美国的社会生活。他对战后美国社会的批评包括政治腐败、种族歧视、教育制度、宗教生活等方面。这些批评都是温和的、善意的。80年代以后，随着他对美国民主制的认识深化，讽刺成分增多，后期发展到愤怒的抗议甚至悲观失望。马克·吐温是幽默艺术的大师。他在滑稽中含有讽刺，逗趣中有所针砭，创造了独特的艺术风格。 心理分析小说家亨利·詹姆斯 道德情操方面更偏向于文化修养不高的美国人。美国人心地纯真、善良；比欧洲人(或常任欧洲的美国人)可爱，这是他的《贵妇人的画像》(1881)等小说中常出现的主题。他开创了心理分析小说的先河，他的作品，尤其是后期作品如《鸽翼》(1902)，不厌其详地发掘人物“最幽微、最朦胧的”思想与感觉，把“太空中跳动的脉搏”转化为形象。在心理分析精微细致这一点上，詹姆斯达到前所未有的境界，为小说艺术的表现力开辟了新的途径。 现实主义文学的兴起 美国黑人文学起源于黑人奴隶歌曲，这些歌曲，不论是悲歌还是民歌，倾诉了黑人背井离乡、沦为奴隶的痛苦心情。书写文学最早出现在18世纪，19世纪以后陆续增多。表现形式先是诗歌，再是小说。作者多数是已经获得自由的黑人。除少数迎合白人读者的口味外，多数作家倾吐黑人奴隶的苦难，控诉蓄奴制的罪恶。南北战争前后，以道格拉斯(1817－1895)为首的黑人作家提出废除蓄奴制、争取黑人人权的要求。黑人文学的战斗性增强。南北战争后出现的诗人邓巴(1872－1906)、小说家切斯纳特(1858－1932)在艺术上更为成熟，前者想象丰富，表现含蓄，后者揭露了战后南方种族歧视的状况，但对白人统治者又存有幻想，反映了黑人知识分子的思想倾向。 次世界大战之间 ，有接近劳动人民的芝加哥诗派，有20世纪的田园诗人，有新的乡土主义者，有抽象哲理派诗人。他们的共同点是表现现代资本主义社会中越来越突出的人的异化，并或多或少流露出仿惶和悲观的情绪。即使是田园诗，弗罗斯特笔下的新英格兰风光也笼罩着疏远、陌生与死亡的阴影。现代派诗歌的代表作是艾略特的《荒原》(1922)。这首诗为西方现代社会提供了一个象征性的比喻。现代主义在戏剧方面的代表人物是奥尼尔，他的剧作受到象征主义、表现主义和弗洛伊德主义的影响。他对美国社会的合理性表示怀疑，创造了美国现代的悲剧。在小说方面，格·斯泰因(1874－1946)与舍·安德森(1876－1941)开创了美国现代派小说的道路。迷惘的一代 这个时期传统现实主义的文学作品仍然不断出现，并且有所发展。德莱塞这个时期的作品，包括《欲望三部曲》(1912，1914，1947)和《美国的悲剧》(1925)，对现实的反映和批判越来越深刻。辛·刘易斯的《大街》(1920)粉碎了“村镇是美好的世外桃源”的神话。他后来的作品对商业、科技、宗教界的问题都作了揭露，他所塑造的巴比特成了庸俗、浮夸、讲求实利的中产阶级的典型人物。女作家蔽拉·凯瑟(1873-1947)以歌颂拓荒者开始，进而批判金钱势力，后来又从历史中去发掘现代美国所缺乏的精神美。“哈莱姆文艺复兴” 加了反法西斯斗争，他们的作品提醒人民要警惕新的威胁。 “南方文艺复兴” 美国19世纪的戏剧并不发达，剧本缺乏文学价值。1915年以前，商业化倾向严重，多数剧作可以用“挤人眼泪、逗人乐、吓唬人”几个词来概括。在这以后的25年里，美国的戏剧赶上了世界水平。大学里设立了戏剧课，小剧场雨后春笋般出现，冲击了戏剧界的商业习气。百老汇本身也进行了一些改革。奥尼尔是新戏剧运动的主力。他的特点是把枯燥乏味的日常生活与美好的梦想加以对照，同时用大胆创新的戏剧手法表现出来，以达到哲理、心理的高度，代表作有《天边外》(1920)、《哀悼》(1931)等。当时还涌现出一大批优秀的剧作家，有的用新奇手法揭示机器对人的压迫，有的用爵士乐般喧闹的节奏表现下层社会复杂多样的生活，有的写出了有心理深度的社会批判剧，有的通过小人物日常生活发掘善良、优美的人性。这个时期是美国戏剧的“黄金时代”。“新批评” 第二次世界大战规模空前。战争中发生的事，如600万犹太人被屠杀，原子弹在广岛爆炸，使美国知识分子感到震惊。他们怀疑人性是否还有善良的一面，也感到人难以控制自己制造出来的巨大物质力量。他们对文明与进步的信念发生了极大动摇。50年代在“冷战”、麦卡锡主义和朝鲜战争的背景下，文坛趋于沉寂；印、70年代，经过越南战争、民权运动、学生运动、女权运动、水门案件，文坛活跃起来，出现了一批爱思索的作家。在他们眼里，美国的社会变得十分复杂，价值观念混乱。他们普遍感到不知怎样解释这样的现实，于是便通过怪诞、幻想、夸张的方式，再现生活中的混乱、恐怖和疯狂。他们表现的是没有目标与 战后出现的第一股文学浪潮是战争小说。其中较好的是梅勒的《裸者和死者》(1948)和詹姆斯·琼斯的《从 50年代，右翼保守势力向30年代激进主义传统进攻，许多人由关心社会进步转而关心个人的私利。这10年被称为“怯懦的十年”或“沉寂的十年”。这期间，出现了一些作品，将资产阶级描绘成正面人物，鼓吹服从权威，如《穿灰法兰绒衣服的人》(1955)。这类作品企图维护既定价值标准和现存社会秩序，很快就失去了影响。另一方面，阿瑟·米勒等作家抵制麦卡锡主义，继续用作品抨击社会的不正义。 “垮掉的一代” 50年代沉闷的政治空气使许多青年感到窒息，他们吸毒、群居，以颓唐、放纵的生活方式来表示自己的抗议。其中有些人把这种生活与情绪写入文学作品，这便是“垮掉的一代”文学。这种文学发展到60年代后，在国内民主运动高涨的背景下，增加了一些政治色彩。但是对他们中许多人来说，东方宗教与东方哲学更具有吸引力。“垮掉的一代”在诗歌创作方面较有生气，并恢复了美国诗歌朗诵的传统。 “黑色幽默” 60、70年代，出现了“新新闻报道”或“非虚构小说”这一种新的文学样式。有些作家认为现实生活的离奇已经超过了作家的想象力，与其虚构小说，不如用写小说的手法来描绘引起社会轰动的事件。这样的体裁允许报道者描写事件时掺杂自己的观察和想象，也可以采用各种象征手法。这种作品比一般报告文学深人细致，其中也包括作者的观察与想象，带有更多的作者个人色彩，艺术感染力较强，例如卡波特的《凶杀》(1966)与梅勒的《刽子手之歌》(1979)。 犹太人文学 美国当代作家中，犹太裔作家占相当大的比重，犹太人文学几乎可以视为一种“次文化”或“文化支流”。犹太人文学作品一般都具有古老的欧洲文化与现代的美国文化的双重色彩，两种文化的冲突与归并使犹太人文学增加了复杂性。宗教思想与同胞遭到屠杀使犹太作家产生犯罪感与负疚感，历史的命运又使他们有流浪感与漂泊感，美国的异化社会也使他们感到找不到归宿。因此，寻找“自我本质”便成为他们的作品中一个突出的主题。有代表性的作品是贝洛的《奥吉。玛琪历险记》。实际上，这是犹太民族确立自己的民族地位与民族尊严的一种表现。70年代后期，代表西方较新思想体系的贝洛与属于意第绪文化传统的辛格(1904- )相继得到诺贝尔奖金，说明犹太人文学在美国文学中的重要性。其他重要的犹太作家还有马拉默德 战后黑人文学更趋成熟。拉尔夫·埃利逊 (1914- )的小说《看不见的人》和鲍德温的散文，均已达到第一流 南方文学这个时期仍有发展，老作家福克纳、波特(1890-1980)、威尔蒂(1909- )仍有重要作品问世。新作 纽约的作家不象南方作家那样具有某种共同的心理因素。人们把他们归在一起，是因为他们都为纽约的几家杂志(《党派评论》、《纽约书评》与《纽约人》)写作，这几家杂志上发表的评论与小说往往对美国文学的时尚产生影响。利·特里林(1905-1975)与玛·麦卡锡(1912- )是很有见地的评论家，约翰·契弗 (1912- )与厄普代克(1932－)的小说用含有诗意又带有嘲讽的细腻的笔触探索大城市郊区居民的心理和意识，为东北部的中产阶级描绘了一幅幅工笔精致的风俗画。 个性化的诗歌 杰克·伦敦（Jack London，18766－1916）原名约翰·格利菲斯·伦敦（John Griffith London），生于美国旧金山，大约是个占星术家的私生子，在一个既无固定职业亦无固定住所的家庭中长大。十四岁小学毕业，就辍了学，在旧金山和奥克兰一带以各种方式求生，亦以养家。二十岁时曾进加州大学读书，一学期后即因贫困辍学。1900年出版了第一个小说集《狼子》（The Son of the Wolf），立即誉满全国，那时他二十四岁。到1916年他年满四十时，已出版了五十一部著作，是很高产的作家。他的作品在当时独树一帜，充满筋肉暴突的生活和阳刚之气，最受男子汉的欢迎。有人说在他以前的美国小说大都是为姑娘们写的，而他的作品则属于全体读者。不但普通读者欢迎，就是大家闺秀们也喜欢放下窗帘关上大门偷偷去品味他那精力旺盛、气势逼人的作品。他在现代美国文学和世界文学里都享有崇高的地位。十七岁时，他上了一艘捕猎船做水手，经过朝鲜、日本，到西伯利亚去捕海豹。途中经受了严寒、风暴、最沉重的苦役的锻炼。因为从小在海湾里玩船，驾船很有本领，年纪虽小却深得船主和同伴们赞许。又因为从小饱经摔打，能够在水手舱里参加水手们最野蛮的活动，交了许多朋友；听见了许多故事。这时，杰克·伦敦逐渐从早期的蒙昧中醒悟了过来。他立志掌握当时最先进的技术：电气，便到奥克兰电车公司的发电厂去求职。他对经理说为了学习技术他什么苦都可以吃，经理便让他一天干活十三个小时，没有星期天，把他累得死去活来。后来他才知道实际上有两个工人被他顶去了工作，那两个人每月各四十元，共是八十元，而他一个月才拿三十元。而且一个被他夺去工作的人因为有一妻三子要养活，却又无法为生，便自杀了。这对于杰克·伦敦是一次极其深刻的教训，他愤然抛下了手中的煤铲。这次苦役使他懂得了一个可怕的真理：无论自己如何身强力壮，十年二十年之后总会有更年轻力壮的人来接替他，把他扔到垃圾堆里去。他一直对读书就有兴趣，就连在做蚝贼时他也在他那小船上读过许多书。流浪归来他开始了大量的阅读。他读圣西门、傅立叶、蒲鲁东的作品，明白了私有财产的罪恶；他读马克思的《共产党宣言》，大体懂得了共产主义是怎么回事。为了读书，他十九岁时进了奥克兰中学，准备考大学，同时加入了社会党。那时的社会党还主要是个文化团体。他参加工人的集会，并发表激烈的演说，说资本主义是一种有组织的掠夺制度，主张破坏现有的社会秩序。这在当时是非常犯忌的，他曾因此被捕。2.杰克·伦敦的五十多部作品大体可以分作三大类：描写在大自然中生活的人的作品，描写在城市中生活的人的作品，和论文。
他描写在大自然里生活的入的作品又可分为两类：极地小说和海洋小说。极地小说最有名的有三个小说集：《狼子》，《热爱生命》（Loveof Life，1907）和《丢脸》（Lost Face,191O）；还有长篇小说《燃烧的戴莱特》（Burning Daylig ht，191））和《蹩脚·贝路》（Smoke Bellew，191））；此外有他别具一格的狗小说《蛮荒的召唤》（The Call of the Wild，1903）和《白獠牙》（The White Fang，1906）。《燃烧的戴莱特》的主角是个孔武有力的淘金者，在获得大量黄金之后却怀着理想主义的情绪全部放弃了；《蹩脚·贝路》的主角是个蹩脚记者，在淘金生活中历尽艰险。这些小说描写了北极附近严寒地带的人们在最严酷的环境下的艰苦生活和撼人心魂的斗争。例如短篇小说《生火》写一个淘金者在零下七十度的旷野里用各种办法生火终于失败而死的故事，很为悲壮。两本狗小说一本写文明世界的狗回到蛮荒，一本写经过凶残训练的狗回到文明，都是从狗的本性出发，反映人类感情对狗的影响的；写的虽是狗，反映的却不仅是狗，而包括了周围的人的思想、感情和性格。
他的海洋小说包括了小说集《南海故事》（1911）和长篇小说《海狼》（Sea Walf，1911）等，还有一个狗故事《群岛猎犬杰瑞》（Jerry of the lslands，1917）。《南海故事》的南海指的是南太平洋，包括了夏威夷群岛及广大的海域及岛屿。小说集仿佛是南太平洋上著居民的展览会和当地风光的画廊。《海浪》写的是捕猎海豹的船只“幽灵号”船长拉尔森的冒险故事，他最后因为得了肺癌被遗弃在荒岛上，而被他从海上救起的记者和女诗人却回到了文明社会.《群岛猎犬杰瑞》写一头小猎犬落入食人生番的手里又逃出，回到文明世界的故事。
杰克·伦敦描写城市的作品有著名的长篇幻想小说《铁蹄》（TheIron Heel，1908）、报告文学《深渊里的人们》（The People in the Abyss，1903），小说《拳赛》（The Game，1905）、幻想小说《亚当以前》（BeforeAdam，1906）、《马丁·伊甸》、及《约翰·巴利科恩》（JohnBarleycorn，1913）等。《铁蹄》预言了美国的金融寡头将组织成为法西斯机构“铁蹄”，控制全国，进行军事寡头统治和特务统治，而社会主义者只好与德国的工人阶级联合举行总罢工，以反对美国发起的对德战争，并用以暴力对暴力的形式进行地下斗争，最后男主角埃佛哈不幸牺牲，记载故事的文稿也便中断。文稿及以脚注的形式预言法西斯组织“铁蹄”要到三百年后才能被推翻，那时人类也就进入幸福的集体主义时代。《约翰·巴利科恩》是以禁酒为主题的小说，也带有自传性质。《拳赛》写一个拳击手的悲剧，拳击手要他的情人去看他比赛，用以消除她对拳击的成见，却在拳击时被重伤致死。《亚当以前》是另一本幻想小说，是一种把达尔文和华莱士的理论通俗化的尝试，写的是冰河期中期的原始人类的故事。
对杰克·伦敦的作品有人评论为：干净利落，生气勃勃，健康乐观；也有人认为是文明的头脑与原始的强力的结合，是科学进化论的喉舌，代表了朝气和勇敢。杰克·伦敦最擅长的是对于原始暴力和个人奋斗的描写，这在他的极地小说和海洋小说中表现得最为明显。《马丁·伊甸》里也有一些原始暴力的描写，比如那场从六岁打到十七岁，历时十一年之久的苦斗就是一个例子。而马丁·伊甸的整个历史其实也是一篇惊心动魄的个人肉搏史。
他的论文有论文集《阶级战争》（The War of the Classes，1905）、《人类去向》（The Human Drift，1917）和《革命》等。他的论文也像小说一样受到欢迎，这是令他的出版商都感到惊讶的。例如《阶级战争》在一年之内就曾三次再版。美国是个敌视社会主义的国家，但杰克·伦敦的宣传阶级战争的文集竟会这样畅销，说明了他的作品有惊人的魅力。
杰克·伦敦曾是世界上名气最大的作家之一。他的作品大多出版不久就被译成各国文字出版，包括法文、俄文。德又、瑞典文、丹麦文、荷兰文、西班牙文、意大利文、希伯来文等，因为意识形态的关系，他的作品在俄国和前苏联最受欢迎，列宁就很欣赏他的《铁蹄》和《热爱生命》。
美国传记小说家伊尔文·斯通在他的《马背上的水手》里称他是美国无产阶级文学之父。The Sea-Wolf/海狼 全文阅读：The Sea-Wolf/海狼 《海狼》在直到1999年的八十多年间中，曾十几次被搬上银幕，杰克伦敦在1913年的版本中，出演一位水手。

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Native AmericansNative Americans were living in North America for many hundreds of years before Europeans reached the continent. For a long time white people called them Indians. Today, many people do not like this name since it is based on a mistake: it was given to the people living in the Americas by Christopher *Columbus who, when he arrived there, thought he had discovered India. Instead, people prefer to use the term Native Americans. There are also native peoples living in *Alaska and Canada, e.g. *Inuits and Aleuts, but they are separate groups and are not called Native Americans.
Early contact with Europeans
In *Pre-Columbian North America there were many tribes who lived by hunting animals and gathering plants. Many of the tribes moved from one place to another according to the season and what food was available. Most of what is known about Native Americans dates from the time when they came into contact with Europeans.
The first place in the US where Europeans settled permanently was *Jamestown, Virginia, founded in 1607. At first Native Americans were positive about the Europeans and were happy to have the many new things they brought, e.g. metal cooking pots, cloth and guns. But the Europeans also introduced diseases that Native Americans had no resistance to, so many became ill and died. They also brought alcohol, the effects of which Native Americans did not know. Some Europeans took advantage of this by getting them drunk and then paying low prices for their goods.
The worst problem for Native Americans, which lasted into the late 20th century, was that the new settlers wanted their land. To native Americans owning land was a strange idea. Tribes moved around as they pleased and shared land with any other tribe that was friendly. They did not understand that a person might believe a piece of land was theirs, or that they would try to keep others from using it. The settlers, on the other hand, assumed that they would take control of North America and used all means to do this, including making agreements, which they usually did not keep, tricking Native Americans into selling land cheaply, and taking it by military force. Native American chiefs like *Sitting Bull, *Tecumseh and *Geronimo fought against the settlers.
As Whites began moving west, Native American tribes had to be moved on. Some were forced to go to other parts of North America, to areas very different from the ones they were used to. The *Trail of Tears was one of many terrible examples: in the cold winter of 18389 17 000 *Cherokees had to move from their land in the south-east to what is now *Oklahoma and more than 4 000 died. The government promised tribes that if they agreed to stay in one part of the country they could keep that land forever. But the promises lasted only until Americans discovered that the land they had given them was good for farming or had gold.
Whites have explained this behaviour in different ways. When the Indians fought and killed white people they said that this proved that Native Americans were wild and had to be controlled. People also believed that the Native Americans were wasting good land by not developing it. In the 19th century Americans believed in *manifest destiny, meaning that they thought God wanted them to occupy the whole continent. They also believed that it was better for the Native Americans to learn to live like white people and tried to teach them Christianity. Many Native American children, including the athlete Jim *Thorpe, were taken away from their tribe and sent to schools where they were not allowed to speak their own language.Native American languagesBefore Europeans arrived in North America there were over 300 Native American languages. Some have now died out, and of the 250 or so remaining many are spoken only by a few older people. Other languages, like Cherokee, are more widely spoken. Most Native Americans speak English, some as their first language and others as their second.
Native American languages have added many words to English, though the meaning of a word has often been changed. Teepees are a kind of tent, *wampum belts were made of beads and since the belts had great value Europeans used wampum to mean ‘money’. Moccasins, a kind of shoe, are today worn by people all over the world. Many Native American words describe the things they name. For example, the Asakiwaki tribe’s name means ‘people of the yellow earth’, and the Cherokees’ name for themselves, Ani-Yun’wiya, means ‘the leading people’. Indian names for Whites included ‘people greedily grasping for land’.
Many American place names have their roots in Native American languages. *Ohio, for instance, is a Native American name, and the names of many of its towns and cities, such as Chillicothe and Sandusky, and the lakes Scioto and Olentangy, are of Native American origin.
Native Americans today
According to the Bureau of Indian Affairs, a part of the US government, there are now about 550 tribes. These include well-known groups like the *Navajo and *Sioux, and less famous tribes like the Cayuse. The number of Native Americans living in the US is about 1.2 million.
Almost a million live on reservations, areas of land that the government has allowed them to keep as their own. Native Americans are US citizens, and have the rights and responsibilities of any US citizen. However, reservations have their own governments and police forces and Native Americans pay different taxes. They also have the right to hunt and fish where and when they like, while other Americans have to get a licence.
On or off the reservations Native Americans find it difficult to live the traditional life. Activities of other Americans affect the way they live. Building dams across a river, for example, can affect the numbers of fish living there, so that even though Native Americans have the right to fish they may not be able to catch anything. Away from the reservations, many Native Americans find that their culture is very different from that of white people and have difficulty adapting.
Poverty is a serious problem. About 37% of people who live on reservations are unemployed, compared with 6% of the general population. Many tribes try to bring in money from outside. Some sell rights to search for oil on their reservation, others use the fact that the reservation makes its own rules to open casinos where people from outside can come and gamble. Gambling is illegal in most parts of the US and many Americans want it to remain so, but it makes a lot of money for the tribes. This brings Native Americans, once again, into conflict with white Americans.Native Americans in the popular imagination
An American tradition dating back to early times is *Thanksgiving. When the English arrived in Jamestown many died during the long cold winter, but in the following spring Native Americans showed them what local foods they could eat. In the autumn, well-prepared for the winter, settlers and Native Americans had a special dinner together, the first Thanksgiving, to thank God and the Native Americans for all the food they had.
Another story describes how the Native American princess *Pocahontas saved the life of John *Smith, the leader in Jamestown, when her father, *Powhatan, wanted to kill him. She later married another Englishman, John Rolfe, and went to England with him. The story of Pocahontas is widely known and many Americans are proud to have her as an ancestor.
But Native Americans were more often seen by white settlers as the enemy. *Westerns, i.e. films and books about the *Wild West, use the threat from Indians as their central theme. In this context Native Americans are still called ‘Indians’. Children often play ‘cowboys and Indians’ and pretend to kill each other. When *Buffalo Bill, began touring the US with his Wild West show, the chief Sitting Bull was one of many Native Americans in it, and many people went to see this former great enemy.
Many Americans have an image of a ‘typical Indian’, a chief who lived in a teepee with his squaw (= wife), smoked a peace pipe after signing a treaty with the white man (whom he called pale face), sent smoke signals to communicate with people far away, and spoke broken English full of colourful expressions such as ‘big heap wampum’ (a lot of money) and ‘speaks with forked tongue’ (is lying). Most of these ideas have some basis in Native American culture, but it is wrong to put them all together and believe that that was how Native Americans lived.
Americans make such mistakes because they have little interest in Native Americans. Having succeeded in pushing them out of the way onto reservations, most Americans ignore them. This may be because the Native Americans who are left are living proof of a hard truth: America wants to be, and often is, a land where everyone has a chance and where the government behaves fairly and honestly to all, but this America is built on land stolen from the people who lived there first. George Washington (1732-99)the first US *President (1789-97), who had led its army to success in the *American Revolution. He is called ‘the Father of His Country’. The *Continental Congress placed him in charge of the American forces in 1775. Although his army had a difficult and dangerous winter at *Valley Forge, General Washington led them to several victories, including the final Battle of *Yorktown. He later gave his important approval for the *American Constitution and was elected in 1789 as the country’s first president. He supported a strong central government but disliked political party arguments. He was elected a second time, but refused to stand as a candidate for a third time and returned to his home at *Mount Vernon.
Americans have always admired Washington as one of their best and most moral presidents. He is considered by many to have been the country’s greatest leader and perhaps the only one who could have united the colonists during the American Revolution. Most people know the story of how as a boy he cut down his father’s cherry tree and then admitted what he had done, saying, ‘I cannot tell a lie.’ The story may not be true but it is seen as a symbol of his honesty. Washington’s fine personal qualities and fair politics were recognized during his life, and they seem even more impressive today. His memory is honoured by the *Washington Monument and the names of the country’s capital city, a state, many *counties, government buildings, schools, streets, mountains, etc, and his image appears on the dollar note and the 25-cent coin. Washington, DC (Washington, District of Columbia)
the capital city of the US, whose area covers the *District of Columbia. The place was chosen by George *Washington in 1790, and since 1800 the main departments of the US government have been there. It is known for its historical monuments and important buildings, including the *Capitol, the *White House(1), the *Supreme Court, the *National Archives, the *Library of Congress, the *Smithsonian Institution, the *National Gallery of Art and the *Kennedy Center. About 66% of Washington’s population are *African Americans.
Washington Monumenta tall, thin monument on The *Mall(2) in *Washington, DC, built to honour the memory of George *Washington. It is 555 feet/169 metres high and made of white marble. Tourists can climb the 898 steps to the top, from which there are fine views of the city. The Monument took 40 years to build and was completed in 1888. jazz
Jazz is one of the greatest forms of music originating in the US. The names of its stars, who are mostly *African Americans, are known around the world. Most people have heard of stars like Ella *Fitzgerald, ‘Count’ *Basie, ‘Duke’ *Ellington and Louis *Armstrong. Wynton *Marsalis, who plays in the traditional style, is the best-known jazz musician today.
Jazz was begun in the *South by African Americans. Many of its rhythms came from the work songs and spirituals (= religious songs) of black slaves. New Orleans street bands first made jazz popular. Early forms of jazz created at the beginning of the 20th century were *ragtime and the *blues. Ragtime musicians included the singer ‘Jelly Roll’ *Morton and the composer and piano player Scott *Joplin. Famous blues singers included Bessie *Smith and later Billie *Holiday. *Dixieland developed from ragtime and the blues and made a feature of improvisation (= making up the music as it is being played), especially on the trumpet and saxophone. Dixieland stars included Louis Armstrong and Sidney Bechet.
In the 1920s many African Americans moved north, taking jazz with them, and *Chicago and New York became centres for the music. This was the beginning of the big band era. In the 1930s swing music came into fashion and people danced to jazz. Radio and the new recording industry helped to make it even more popular. The big bands were led by Basie, Ellington, Woody *Herman, Glenn *Miller and ‘the King of Swing’, Benny *Goodman. In the 1940s there were new styles such as *bebop, developed by ‘Dizzy’ *Gillespie, Charlie ‘Bird’ *Parker and Thelonious *Monk. Freer forms like progressive jazz developed in the 1950s with stars including Stan *Getz and Dave *Brubeck. Cool jazz followed in the 1960s, led by Getz and Miles *Davis. More recent styles have included funky jazz, jazz-rock and hip-hop jazz. Many jazz clubs, like the *Cotton Club, have now closed but others, like Preservation Hall in *New Orleans, and Birdland in *Manhattan, remain.
In Britain jazz attracts a small but enthusiastic audience. The height of its popularity was in the 1940s and 1950s, when large crowds gathered to hear big bands. British jazz has always been heavily influenced by US jazz. In the 1960s pop and rock music replaced jazz as the music of the young generation. There are now few jazz bands, although smaller combos (= groups) continue to play a wide range of trad (= traditional), bebop, cool and avant-garde jazz. The most famous British jazz musicians have included Johnny *Dankworth and Cleo *Laine, George Melly, Humphrey *Lyttelton and Courtney *Pine. The home of jazz in Britain is Ronnie *Scott’s club in London. MAYA1.Maya CultureThe Maya are probably the best-known of the classical civilizations of Mesoamerica. Originating in the Yucatán around 2600 B.C., they rose to prominence around A.D. 250 in present-day southern Mexico, Guatemala, northern Belize and western Honduras. Building on the inherited inventions and ideas of earlier civilizations such as the Olmec, the Maya developed astronomy, calendrical systems and hieroglyphic writing. The Maya were noted as well for elaborate and highly decorated ceremonial architecture, including temple-pyramids, palaces and observatories, all built without metal tools. They were also skilled farmers, clearing large sections of tropical rain forest and, where groundwater was scarce, building sizeable underground reservoirs for the storage of rainwater. The Maya were equally skilled as weavers and potters, and cleared routes through jungles and swamps to foster extensive trade networks with distant peoples.
Around 300 B.C., the Maya adopted a hierarchical system of government with rule by nobles and kings. This civilization developed into highly structured kingdoms during the Classic period, A.D. 200-900. Their society consisted of many independent states, each with a rural farming community and large urban sites built around ceremonial centres. It started to decline around A.D. 900 when – for reasons which are still largely a mystery – the southern Maya abandoned their cities. When the northern Maya were integrated into the Toltec society by A.D. 1200, the Maya dynasty finally came to a close, although some peripheral centres continued to thrive until the Spanish Conquest in the early sixteenth century.
Maya history can be characterized as cycles of rise and fall: city-states rose in prominence and fell into decline, only to be replaced by others. It could also be described as one of continuity and change, guided by a religion that remains the foundation of their culture. For those who follow the ancient Maya traditions, the belief in the influence of the cosmos on human lives and the necessity of paying homage to the gods through rituals continues to find expression in a modern hybrid Christian-Maya faith.
Cosmology and Religion
The ancient Maya believed in recurring cycles of creation and destruction and thought in terms of eras lasting about 5,200 modern years. The current cycle is believed by the Maya to have begun in either 3114 B.C. or 3113 B.C. of our calendar, and is expected to end in either A.D. 2011 or 2012.
Maya cosmology is not easy to reconstruct from our current knowledge of their civilization. It seems apparent, however, that the Maya believed Earth to be flat and four-cornered. Each corner was located at a cardinal point and had a colour value: red for east, white for north, black for west, and yellow for south. At the centre was the colour green.
Some Maya also believed that the sky was multi-layered and that it was supported at the corners by four gods of immense physical strength called “Bacabs”. Other Maya believed that the sky was supported by four trees of different colours and species, with the green ceiba, or silk-cotton tree, at the centre.
Earth in its flat form was thought by the Maya to be the back of a giant crocodile, resting in a pool of water lilies. The crocodile’s counterpart in the sky was a double-headed serpent – a concept probably based on the fact that the Maya word for “sky” is similar to the word for “snake”. In hieroglyphics, the body of the sky-serpent is marked not only with its own sign of crossed bands, but also those of the Sun, the Moon, Venus and other celestial bodies.
Heaven was believed to have 13 layers, and each layer had its own god. Uppermost was the muan bird, a kind of screech-owl. The Underworld had nine layers, with nine corresponding Lords of the Night. The Underworld was a cold, unhappy place and was believed to be the destination of most Maya after death. Heavenly bodies such as the Sun, the Moon, and Venus, were also thought to pass through the Underworld after they disappeared below the horizon every evening.
Very little is known about the Maya pantheon. The Maya had a bewildering number of gods, with at least 166 named deities. This is partly because each of the gods had many aspects. Some had more than one sex; others could be both young and old; and every god representing a heavenly body had a different Underworld face, which appeared when the god “died” in the evening2.The Maya Calendar:The Maya kept time with a combination of several cycles that meshed together to mark the movement of the sun, moon and Venus. The Maya calendar in its final form probably dates from about the 1st century B.C., and may originate with the Olmec civilization. It is extremely accurate, and the calculations of Maya priests were so precise that their calendar correction is 10,000th of a day more exact than the standard calendar the world uses today.
Of all the ancient calendar systems, the Maya and other Mesoamerican systems are the most complex and intricate. They used 20-day months, and had two calendar years: the 260-day Sacred Round, or tzolkin, and the 365-day Vague Year, or haab. These two calendars coincided every 52 years. The 52-year period of time was called a “bundle” and meant the same to the Maya as our century does to us.
The Sacred Round of 260 days is composed of two smaller cycles: the numbers 1 through 13, coupled with 20 different day names. Each of the day names is represented by a god who carries time across the sky, thus marking the passage of night and day. The day names are Imix, Ik, Akbal, Kan, Chicchan, Cimi, Manik, Lamat, Muluc, Oc, Chuen, Eb, Ben, Ix, Men, Cib, Caban, Eiznab, Cauac, and Ahau. Some of these are animal gods, such as Chuen (the dog), and Ahau (the eagle), and archaeologists have pointed out that the Maya sequence of animals can be matched in similar sequence to the lunar zodiacs of many East and Southeast Asian civilizations. 3.Writing and Hieroglyphics:The Maya writing system is considered by archaeologists to be the most sophisticated system ever developed in Mesoamerica.
The Maya wrote using 800 individual signs or glyphs, paired in columns that read together from left to right and top to bottom. Maya glyphs represented words or syllables that could be combined to form any word or concept in the Mayan language, including numbers, time periods, royal names, titles, dynastic events, and the names of gods, scribes, sculptors, objects, buildings, places, and food. Hieroglyphic inscriptions were either carved in stone and wood on Maya monuments and architecture, or painted on paper, plaster walls and pottery.
The unit of the Maya writing system is the glyphic cartouche, which is equivalent to the words and sentences of a modern language. Maya cartouches included at least three or four glyphs and as many as fifty. Each cartouche contained various glyphs, as well as prefixes and suffixes. There is no Maya alphabet.
Maya writing is difficult to interpret for a number of reasons. First, glyphs do not represent just sounds or ideas, they can represent both, making it difficult to know how each glyph or cartouche should be read. In addition, many Maya glyphs can have more than one meaning, and many Maya concepts can be written in more than one way. Numbers, for example, can be written with Maya numerical symbols or with the picture of a god associated with that number, or a combination of the two. Some glyphs represent more than one phonetic sound, while also representing an idea. This means that a single idea can be written in many different ways. For example, the name of the Palenque ruler, Pacal, whose name literally means “Hand-shield”, appears sometimes as a picture of a hand-shield, sometimes phonetically as pa-cal-la, and at other times as a combination of picture symbols and phonetics.
（http://www.civilization.ca/civil/maya/） 霓虹灯
A neon light is the sort of light you see used in advertising signs. These signs are made of long, narrow glass tubes, and these tubes are often bent into all sorts of shapes. The tube of a neon light can spell out a word, for example. These tubes emit light in different colors.
The idea behind a neon light is simple. Inside the glass tube there is a gas like neon, argon or krypton at low pressure. At both ends of the tube there are metal electrodes. When you apply a high voltage to the electrodes, the neon gas ionizes, and electrons flow through the gas. These electrons excite the neon atoms and cause them to emit light that we can see. Neon emits red light when energized in this way. Other gases emit other colors.

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美国大都市洛杉矶
洛杉矶是美国第三大都市，位于充满阳光的西海岸。好莱坞是妇孺皆知的电影王国，狄斯耐乐园更是全球闻名的游乐园地。加州蜜橘堆积如山，而中国城则充满中国传统气氛。洛杉矶乃是生气蓬勃的美国观光胜地。
　　好莱坞Hollywood 曾被誉之为”电影城”，最近因为电视盛行，在该处摄制的电影也就相对减少。不过，哥伦比亚、派拉蒙等著名电影公司仍在继续拍片。好莱坞的主要街道是SunsetBlvd.与HollywoodBlvd.街道两旁是电影际与高级的商店，极尽繁华之能事。好莱坞有一座戏院Grauman’sChineseTheater,几乎所有著名的影星都印下他(她)们的手印或足印。HollywoodBowl则因在星光下露天演奏交乡曲而闻名。HollywoodBemetery是著名影星的墓地，都值得一游。
　　环球影城UniversalCityStudios 是世界上最大的摄影棚，其中有人工瀑布，人工湖，拍摄电影用的各种道具布景、服装等等。这个摄影棚对外开放，只需购买参观券就能入内亲眼欣赏电影的情形。
　　莫维兰蜡像馆MovielandWaxMuseum 馆中有著名影星的蜡像，和若干著名电影镜头的模型。
　　比华利山BeverlyHills 电影中经常出现的好莱坞西侧的高级住宅区。著名影星、名道演及富豪在那里都拥有自己的住宅或别墅。
　　魔积山MagicMountain 是一个令人紧张刺激的游乐场所，园地内有40多种乘坐的工具，可以自由搭乘，令人油然产生新奇之感。
　　迪斯耐乐园Disneyland 全球闻名的迪斯耐乐园，设在距洛杉矶40公里的Anaheim。迪斯耐乐园建于1955年，乐园占地150平方英尺，如欲窥其全貌，得花两天时间。
　　园内主要设施计有”童话世界”、”明日世界”、”拓荒世界”、”冒险世界”、”纽奥良广场”等。各种娱乐活动或令人赏心悦目，或使人紧张刺激，是每一个游玩过迪斯耐乐园的人都觉得留连忘返的地方。
　　著名的卡通、如《白雪公主》等片，也是迪斯耐的产品。令人喜爱的米老鼠是迪斯耐的象征，也是一代又一代儿童的宠物。
================ 波士顿
麻萨诸塞州的首府波士顿，乃是美国最早开辟的一个都市。1630年，八百名英国清教徒来到这里，建立村落，波士顿随之而产生。波士顿融合了保守与进步，在弥温历史性气氛中，逐渐发展成一个现代化工业都市。同时，设在该处的哈佛大学、麻萨诸塞理工学院、波士顿大学等最高学府，每年造就不少杰出人才，因而又以文化都市而著称。和其他美国都市有尽相同的是，它充满了欧洲的轨迹。===============费城
独立纪念馆IndependenceHall
建立于1732年，原为州政府，后于1776年7月，在该处发表独立宣言。其后，又在该处起草合众国宪法，从而诞生了美利坚合众国。
议事厅CongressHall
与独立纪念馆连接的建筑物。1790年到1800年为止，该处为联邦议事厅。华盛顿曾在该处被推选第二次担任总统。厅内留存历史性遗物极众。
罗斯故居BetsyRossHouse
这是设计美国国旗星条旗的罗斯夫人的老家。据说，它是1774年由华盛顿总统建议而兴建的。附近的Elfreth’sAlley和BladenCoat小路仍留存了十八世纪美国开国初期的形迹，散步其间，易兴思古幽情。
罗丹博物馆rodinMuseum
是除了法国之外，收藏名画家罗丹作品最多的一家博物馆。
宾州美术馆PennsylvaniaAcademyOfTheFineArts
创设于1801年的美国最古老的美术馆。美国美术界的杰作，几乎都收藏在该馆。
佛兰克林科技馆FranklinInstitute
为了纪念本杰明·佛兰克林的贡献而兴建的科学博物馆，展出运输、航空、物理、天文、化学资料。汽车城
底特律是众所周知的美国汽车工业的王国。福特汽车公司、通用汽车公司和克莱斯勒汽车公司等世界第一流汽车公司都在这里设厂，日生产汽车。
福特汽车公司的Rouge工厂
自铁块开始，至新车装配完成为止，生产过程全部自动化。汽车工业先驱者福特工厂，周一到周五，上午九时至下午三时每30分钟一次免费参观；但八、九两月间，此项免费参观停办。
通用汽车公司的Cadillac分厂
美国最高级汽车卡迪拉克牌汽车的装配工厂。免费参观旅行是周一到周五，9:30和13:30每天两次。但6月1日至10月15日间停办。
克莱斯勒公司的Chrysler&Imperial装配工厂
是Chrysler和Imperial牌汽车的装配工厂。免费参观是周到到周五，9:30和13:00每天两次。
绿野村GreenfieldVillage
是汽车大王亨利·福特拥有的具有历史性的村庄。村内以一览图方式，介绍长达三世纪的美国的生活。在100多幢建筑物中观光者能一目了然地看到美国科学、工业、农业、政治、经济的进步过程。绿野村边是亨利·福特博物馆HeryFordMuseum，陈列着福特公司初期以迄现在的每一种产品，是爱好汽车者必游之地。
贝尔岛Bellelsland
底特律河上一小岛。整个岛开辟成一座公园，内有游乐园、汽艇、泳池、动物园、高尔夫球场以及郊游园等设施。
威因堡宫事博物馆FortWayneMilitaryMuseum
保存着南北战争以前的碉堡，展示早期的营房、弹药库、军用品等。
底特律自然动物园DetroitZoologicalPark
是世界著名的自然动物园，有39种动物在自然天地中生活。园内的HolbenAmphitheater中有猩猩和小马的表演，可免费欣赏
议坛之城
芝加哥系美国第二大都市，也有人称之为“美国的超级市场”TheSuperMarketofAmerica。无论从那一个角度看来，它都是一个典型的美国式都市，既是商业中心，又是交通要卫，市内到处是在建筑史上占一席地位的奇丽建筑物。可眺望密歇根湖的公园，蜿蜒的水际线，另有一番美妙景色。还有，无论是国际性会议，或美国国内较大规模的会议，大都在这一都市举行，因这又获得“议坛之城”的别称。
华丽的一英里TheMagnificentMile
自ChicagoAvenueBridge往北，到EastOakStreet之间的七条街，称之为TheMagnificentMile，可与纽约第五街媲美，有整齐、美丽的行道树，宏伟的高层建筑物，优雅的商店以及赏心悦目的橱窗陈列品。ChicagoAvenueBridge的桥头，就是以口香糖闻名的WrigleyJuniorCo.大厦，大厦下方即为汽艇码头。那个极像是玉蜀黍的TwinTowersMarinaCity也矗立在面向河川的右侧。发行数量占全美国第三位的芝加哥论坛报也以这里为根据地。WaterTower过去被认为是象徵芝加哥的著名大厦。
约翰汉寇克中心JohnHancockCenter
别名“BigJohn”(大约翰)，是一幢高达100层的建筑物。它的外形像把梯子，初看有些怪异，但即是建筑结构力学上的一项新的成就。这幢大厦属一家保除公司所有，但1楼到5楼是高级时装店，6楼到141楼是公司行号的办公室，42楼以上是公寓，94楼是眺望台，95楼是餐厅，96楼则是鸡尾酒馆。
西尔斯大厦SearsTower
这一幢取代了纽约帝国大厦，成为世界上最高的建筑物，总共103层，高达1，454尺(443公尺)，可以容纳16500人，可以称得上是世界奇观，从地面一层到第103层，有快速专用电梯直达，只需55秒钟，供游客鸟瞰整个芝加哥市，如遇阴天，有如置身云雾之间。
商品市场MerchandiseMart
位于芝加哥河北岸的18层楼建筑物，其规模之庞大，仅次于五角大厦。在市场内出售的商品，自家具到机械，种类达100万种以上。
斐尔特自然史博物馆FieldMuseumofNaturalHistory
在博物学这一范畴，堪称世界第一。恐龙的骸骨、古代埃及的木乃伊、马雅帝国的出土物等，均极珍贵。
林肯公园LincolnPark
位于密歇根湖边，全长8公里，占地480公顷，是芝加哥最大的公园。园内有林肯、歌德、莎士比亚、贝多芬等塑像，还有动物园等设施。黄金之都

旧金山，美国西部最早开发的大都市，它是早期华人集居的地方，因此亦称为“大埠”。整个城市环山抱海，充满了诗情画意。它是美国太平洋岸的大商港，也是美国西部的金融中心，旧金山弥漫着浪漫的艺术气氛，它是各种稀奇古怪文化滋生的地方，如六十年代的“嬉皮”和近年来的“同性恋”都是旧金山的产物。===============纽约帝国大厦EmpireStateBuilding
长时期来象征著纽约摩天大楼的高达102层超高层大厦。顶层高度达1，250英尺(381公尺)。在第86楼上有一展望台，气候晴朗时，可以眺望周围50英里以内的景色。
洛克斐勒中心RockefellerCenter
呈现美国典型的一面，在都市建筑学方面也颇饶兴趣的商业与娱乐中心。自第49街与第50街之间，通过第五街的PromenadeGardens内，四季花草茂盛，美丽如图画，公园四周是具有代表性意义的大厦，诸如PCABuilding、RadioCityMusicHall,CenterTheatre等。NBC与ABC的制作室就是RCA大厦的第70楼。
自由女神StatueofLiberty
世界著名的自由女神像，位于纽约湾的利勃坦岛上，像高约46公尺。自由女神像内部中空，可搭电梯直达神像头部。此外，还有新设的移民博物馆ImmigrationMuseum。
联合国theUnitedNations
纽约的历史系由曼顿产生，而现代世界史则与联合国密切相关。自第42街起直到第48街上，在广达18英亩的地基上，就兴建着著名的联合国大厦。联合国容许观光客依到达先后次序入内参观会议情形。
中国城Chinatown
中国城已具有百年以上的历史，城内居住的华裔第二代约有六千人。中国城位于ChathamSquare的西边一部份，城中主要街道为Mott。城内有中国博物馆。大都会美术馆TheMetropolitanMuseumofArt乃是世界最大美术馆之一。自由代东方到现代，有关美术史的重要事项，一一呈现眼前。内中有一美国馆，可由馆中陈列品窥知初期美国人的生活状况。
华尔街WallStreet
是全球金融中心。世界最大的银行大厦，除了大通银行之外，纽约股票交易所，美国股票交易所，以及收藏1789年华盛顿就任美国第一任总统时的史迹的国立纪念馆、联邦厅等，都在这条街上。
世界贸易中心WorldTradeCenter
是纽约一处新的名胜，楼高110层，为世界首屈一指的高层建筑物。在这幢高层建筑物中，除了贸易公司之外，有运输公司、通信机构、银行、保险公司、海关等公私机构，凡与贸易及港湾活动有关的活动，均集中于此。有12万人在建筑物中工作。世界贸易中心占地达16英亩之广。太空城

休士顿是美国的第五大都市，人类第一次登上月球的阿波罗飞船11号就在这里升空，因而使它也成为全球闻名的城镇。这一城镇是在1836年当德克萨斯州自墨西哥获得独立时，随之而诞生。
自从美国国家航空太空总署NASA在近效设置太空中心以来，休士顿正在继续不断地急速发展。
阿斯托洛圆顶运动场Astrodome
耗资3，100万美元，于1965年兴建完成的这一运动场是目前世界上最大的一座室内运动场，内部装有冷暖气设备。棒球、足球、骞马，以至于马戏团表演，都可以在室内进行。紧邻的AstroWorld是一个规模极大的娱乐中心，游客可以观赏欧洲各种村落的景色，也能够欣赏各类表演。
圣哈新托古战场SanJacintoBattlefield
1836年，休士顿将军为了争取德州独立，率军与墨军激战的地方。现在已成为州立公园，纪念塔高达174公尺，可乘电梯登上塔项。塔下是历史博物馆。距休士顿市约26公里。
美国航空太空总署太空飞行中心NASAMannedSpacecraft
因阿波罗11号在此升空而全球闻名。美国国家航空太空总署NASA于1961年设立于休士顿东南方45公里处的克利阿湖畔。附近有GeneralElectric和InternationalBusinessMachines等重要的电子工业企业，是名符其实的航空太空科学中心。太空飞行中心内部极为辽阔，可在进入中心的问讯处索取地图，备作参考。太空中心内也有礼品店，出售太空船模型、月球石头模型，以及阿波罗帽等。牛仔城
达拉斯曾经以经常在美国西部电影中出现而闻名，近年来，因为肯尼迪总统在该城被刺遇害而更成为妇孺皆知的地方。但是，市区内很少有吸引观光客的去处。
勃勒杨小屋BryanCabin
它是拓荒者—约翰·勃勒扬于1841年沿着托里尼坦河建造的小木屋，也是达拉斯最早的建筑物。
美丽公园FairPark
美国规模最大的德州展览会，每年十月就在那里举行，HallofState是园内最著名的美丽建筑物，它是为了纪念德州独立一百周年而于1936年兴建的。园内还有CottonBowlStskium(棉花馆)、GardenCenter(植物园)、MuseumofTexasHistory(德州历史博物馆)，以及水族馆、美术馆等。
达拉斯剧场中心DallasTheaterCenter
这是已故名建筑师法兰克·洛特·莱脱精心设计的剧场，被称之为演剧的圣堂。他终其一生，潜心设计的剧场，也只这一所而已。
肯尼迪总统纪念碑MemorialPlaguetoJohnF.Krnnedy
1963年11月22日，美国总统肯尼迪前往达拉斯竞选，在大街游行时，遇刺殒命，竖碑以资纪念。
白岩湖WhiteRockLake
位于市区东北部，石油大王和德州富豪在湖畔都建有豪华住宅，为白岩湖平添不少景色。
南方美以美教徒大学SouthernMethodistUnivirsity
位于达拉斯市的北部，是美国西南部屈指可数的著名学府，是美以美教会于1915兴建的。美国首都
美国首都华盛顿特区经常受到世界各国的瞩目，它是名副其实的世界政治中心。而法国名建筑师皮埃尔·朗法为它所设计的都市计划，则使它成为全世界有数的美丽都市之一。

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关于钟乳石的形成
石灰岩洞中的钟乳石、石笋是怎样形成的

　　桂林是世界闻名的风景区，山奇水秀，风景美丽，因此自古就有“桂林山水甲天下”之称。桂林除山水美之外，还有更具特色的石灰岩洞，七星岩是比较有代表性的溶洞。洞内到处悬垂着美丽的钟乳石，有的像累累的果实，有的像盛开的花朵。与之相对应的石笋拔地而起，一个个像春天从地面下“冒”出来的竹笋。
　　那么这些奇丽的钟乳石和石笋是怎样形成的呢？
　　原来“盛产”钟乳石和石笋的溶洞都是石灰岩构成的。洞顶有很多的裂隙，每一处裂隙里都有水滴渗透出来。每当水分蒸发掉后，那里就会留下一些石灰质的沉淀，日积月累，天长日久洞顶上的石灰质愈积愈多，终于形成了乳头。以后，乳头外面又包起一层石灰质，以至越垂越长，就形成了姿态万千的钟乳石。
　　石笋其实就是钟乳石的孪生兄弟。当洞顶上的水滴落下来时，石灰质也在地面上沉积起来，就这样石笋对着钟乳石向上长起来，若是说钟乳石是“兄长”，那石笋就是“孪生弟弟”了。
　　而石笋底盘大，本身比较稳定不易折断，所以它比钟乳石的生长速度还要快，还要粗壮呢。

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石化林的一点背景知识
　　石化林存在于美国亚利桑那州的彩绘沙漠内，是广泛散布的石化木和石化树的集聚地。来自火山灰的氧化硅溶于水并且渗入树木中，变成晶体，此时石化木便形成了。人们现在所见到的石化木的鲜艳色彩是由其他矿物质所添加而形成的。　　 　　宝石收藏者过去曾对石化林造成极大的破坏，如今石化木已受法律的保护，无人能再取走哪一片石头。

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芭蕾
初识芭蕾 对于中国观众来说，芭蕾并不陌生，尤其近些年来，芭蕾受到了越来越多的观注，一股“芭蕾热”已经在几座大城市悄然兴起。1997年的“中国歌剧舞剧年”可以说是热闹非凡，各个中外演出团体为广大观众献上了一台又一台精彩的演出，真是“你方唱罢我登场”。从通俗的《天鹅湖》到浪漫的《吉赛尔》，从“拉丁味”的《堂·吉诃德》到充满海南民族气息的《红色娘子军》，一年四季真是月月好戏连台，而且其中不乏经典之作。芭蕾溯源 从运动的实际需要来看，脚尖鞋的发明能够将舞者身体的重量支撑“面”经过若干倍的缩小后变成支撑“点”，从而有效地减小与地面的摩擦力，提高旋转的速度，造成风驰电掣的效果、超凡脱俗的幻觉，进而更好地为仙凡之恋这类虚幻的芭蕾题材服务。从芭蕾的本体美学来说，正是脚尖鞋的使用和脚尖舞的技术使芭蕾与其他种类的舞蹈区别开来。当然这种区别主要只是对女舞者而言的。与民间舞和现代舞相对而言，芭蕾作为一种高贵的西文古典舞，与日常生活的距离是最远的。而在生活与艺术这条从标线上，它是最为艺术化的一种舞蹈。从内容与形式的统一来讲，芭蕾的动作语言作为一种离生活最远的舞蹈形式，最适合表现那种可望而不可及的仙凡之恋的内容，从而完成了形式与内容的高度统一。从芭蕾的审美理想来说，脚尖鞋的使用能够将原本修长的舞者肢体线条进一步拉长，以延伸这种特定的美感，增强了对空间的冲击力，扩大对空间的占有量，并远远超出人体通常解剖结构的比例，加大芭蕾艺术与日常生活的距离，形象生动地体现出“距离即美”的古典美学原则。　怎样欣赏芭蕾 1、旋转：数量和质量的高低是评判芭蕾舞者技术水平高低的核心标准之一，所谓质量，主要指的是旋转过程中，规范的舞姿是否走形，空间的定位是否合乎要求，停止旋转时是否稳定如初，是否能自然而然地完成结尾时的固定舞姿。2、速度：这是衡量芭蕾舞者技术水平高低的又一硬性标尺。速度越快，难度越大，但在有些旋转和跳跃中，加速则是必不可少的，并且能使这些动作完成起来更加容易一些。当然，速度的快慢只是一种技术的标准，而非艺术的标准。这里涉及到了“舞蹈的本质更多的还是艺术，而非技术”的总体原则，尽管没有比较完美和完整的技术，舞蹈也无法成就为艺术。3、方向：这是判别技术高低的第三条标准。在动态中变换方向时，要求力度增减得当，而有经验的舞者都懂得，按照圆形的调度转圈比按照直线的调度转圈难得多，而女子保持在一个固定点上完成32周挥鞭转 ，或男子也在一个固定点上完成几十个二位旁腿转，则往往成为衡量舞者技术水平高低的试金石之一。4、定点看一点：所谓“定点看一点”，指的是舞者在以躯干为垂直轴作急速旋转时，必须用眼睛盯住正前方的某一点不放，即让整个躯干和四肢先转，而将头部，尤其是双眼，留在后面，直到整个头部与身体间的分离程度达到最大极限时，也就是当身体要进行第二次旋转之前的那一刹那，将头部和双眼蓦地跟着整个身体的动势甩过去，并立即以快于躯体的速度，赶在整个身体完成一整圈之前，找到原来的那个视点，然后死死地盯住不放，这是避免舞者头晕的最好方法。这种作法实际上，就是用建军雷不及掩耳的速度，造成一种静态的假象，以利用最短的时间来完成视觉中的这种方向变化，减少平衡器官中的振荡和变化，避免由此产生的晕眩。5、变化手臂或腿脚：在旋转或跳跃中变化手臂或腿脚，是对舞者身体平衡与协调能力的又一大挑战。6、无声而优雅的落地：这应是评判舞者水平高低的又一条标准。7、跳跃的高度：这当然能够增加舞蹈欣赏中的热烈情绪。比较而言，创造绝对高度远不如在瞬间中保持高度，甚至产生在空中停顿片刻的幻觉那样难。在专家的眼睛里，创造出这种幻觉是舞者最为辉煌的技艺之一。就在这个瞬间里作为人的舞者，或者说舞者的人性特征，得到了最大的发扬，而大自然的地心引力则受到了最大的蔑视。8、绷膝盖：这是芭蕾技术中绝对不可或缺的规范。9、绷脚尖：这也是对芭蕾技术完美性的基本要求。10、高抬腿：从接受美学的角度来看，舞者正面对着观众时，向两侧高抬腿更能出效果。11、支撑腿的稳定性：完成这个动作的理想化标准，除了膝盖和脚背需要绷直外，还要求支撑腿如板上钉钉一样，一动不动。12、线条：大致可分两大类，一类是舞者肢体线条，一类则是舞台调度的线条。13、流畅度：按照中外传统舞蹈的路子，编舞家和观众都习惯于要求舞者动作的线条和舞台调度的线条畅若流水。14、双人舞：包括了托举、支撑旋转和平衡三大类动作。杰出的舞伴间的默契除了表现在对双人舞的常规动作达到滚瓜烂熟的程度外，更表现在绝对的相互信任之上。15、大群舞：横竖必须成行，手脚必须到位，动作必须一致，呼吸必须统一，舞句必须流畅，舞者必须协调。大型的群舞中，每位舞者的个性应该加以最大限度的抑制，以便使整个画面保持协调统一。16、动作干净准确：无论是群体还是个体，舞者的动作都 应是干净而准确的。17、舞者在跳舞时，应该表现出充分而优雅的自信，尤其是在完成简单和高难动作之前和之中，不应表现出任何不安来，而应给人如履平地的轻松感和自如感，以及一气呵成的整体感和舒适感。18、快感：舞者作为剧场表演艺术家，其天职应该是给观众提供快感，但要提供快感，舞者本人必须在跳舞过程中先为自己找到快感。19、小骗局：当芭蕾舞者在舞台上未能严格按照上述技术规范，准确地完成各种动作时，会不由自主地作一些小小的补偿或调整，行话称之为“小骗局”。需要向观众解释清楚的是，为了完成某种超出常规运动范畴的动作，使观众产生新奇的美感和快感，采用这种“小骗局”是必要的，而绝对不等于是欺骗观众，就象魔术的神奇就在于它的“骗局”一样。20、从技术向艺术的大跳：在芭蕾演出中，舞蹈会不断改变其视点和强度。解决肢体位置和动作规范的时空力度关系，则是舞者应该在排练中解决的问题。四个间接判别质量高低的视角：

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polymer gels 一种聚合凝胶

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The following information was part of our display for the SET96 and SET98 Scientific Power to the People Exhibition, The Galleries, Bristol, 20th and 21st March 1998.
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A POLYMER is a very long molecule rather like a very long piece of string.
The borax joins two molecules together to make a large network – rather like a flexible scaffolding. This is cross-linking.
This turns the fluid dissolved polymer into a GEL.

In oilwells water is pushed down to push oil up. If this breaks through to the production well bore, the well will just produce water. A solution is to block the rock pores with polymer gel to make the well produce oil again. These gels can be made from naturally occurring sugar-based polymers such as Guar and they can be cross-linked with Cobalt or Chromium.

Other everyday examples of polymer gels are to be found in non-drip emulsion paints, foods, car tyres and agrochemicals.

The polymer that we are using is POLYVINYL ALCOHOL and we are joining the strands together with BORAX. This gel, when coloured, is sold in toyshops as SLIME.

backgrounds of washington
Map of Federal City, 1797
Historical Society of Washington, DC
The plan of the city of Washington was designed in 1791 by Pierre L’Enfant, and mapped the following year; a design which remains largely in place. For nearly a century, the realization of physical changes to the original plan were gradual until the second important benchmark in the development of Washington’s urban plan: the McMillan Commission and its 1901-02 recommendations. The McMillan Commission plans were implemented predominantly during the first three decades of the 20th century, and continued sporadically thereafter. For nearly 100 years, a legal height limit of 160′ has preserved the broad, horizontal Baroque nature of the city, allowing light and air to reach the pedestrian level, and resulting in a picturesque skyline pierced by steeples, domes, towers and monuments.
On January 24, 1791, President George Washington announced the Congressionally-designated permanent location of the national capital, a diamond-shaped ten-mile tract at the confluence of the Potomac and Eastern Branch Rivers. A survey of the area was undertaken by Andrew Ellicott and Benjamin Banneker. Forty boundary stones, laid at one-mile intervals, established the boundaries based on celestial calculations by Banneker, a self-taught astronomer of African descent and one of the few free blacks living in the vicinity. Within this 100 square mile diamond, which would become the District of Columbia, a smaller area was laid out as the city of Washington. (In 1846, one-third of the District was retroceded by Congressional action to Virginia, thus removing that portion of the original district which lay west of the Potomac River.) In March 1791,the surveyors’ roles were complemented by the employment of Major Pierre Charles L’Enfant to prepare the plan.
Major L’Enfant (1755-1825), a French artist and engineer who had formed a friendship with George Washington while serving in the Revolutionary War, requested the honor of designing a plan for the national capital. The fact that the area was largely undeveloped gave the city’s founders the unique opportunity to create an entirely new capital city.
After surveying the site, L’Enfant developed a Baroque plan that features ceremonial spaces and grand radial avenues, while respecting natural contours of the land. The result was a system of intersecting diagonal avenues superimposed over a grid system. The avenues radiated from the two most significant building sites that were to be occupied by houses for Congress and the President.
L’Enfant specified in notes accompanying the plan that these avenues were to be wide, grand, lined with trees, and situated in a manner that would visually connect ideal topographical sites throughout the city, where important structures, monuments, and fountains were to be erected. On paper, L’Enfant shaded and numbered 15 large open spaces at the intersections of these avenues and indicated that they would be divided among the states. He specified that each reservation would feature statues and memorials to honor worthy citizens. The open spaces were as integral to the capital as the buildings to be erected around them. L’Enfant opposed selling land prematurely, refused to furnish his map to the city commissioners in time for the sale, and was reluctantly relieved of his duties by George Washington. Ellicott was then engaged to produce a map and reproduced L’Enfant’s plan from his memory.
In the context of the United States, a plan as grand as the 200 year old city of Washington, DC, stands alone in its magnificence and scale. But as the capital of a new nation, its position and appearance had to surpass the social, economic and cultural balance of a mere city: it was intended as the model for American city planning and a symbol of governmental power to be seen by other nations. The remarkable aspect of Washington, is that by definition of built-out blocks and unobstructed open space, the plan conceived by L’Enfant is little changed today.
The McMillan Plan
As the city approached its centennial, there was a call to develop a comprehensive park system for the city. As early as 1898, a committee was formed to meet with President William McKinley to propose the erection of a monument to commemorate the centennial of the city. A joint committee formed by Congress held its first meeting in February 1900 with Senator James McMillan of Michigan as chairman, and Charles Moore as secretary. At the same time, plans were put forward for the development of a Mall which would include the newly reclaimed Potomac Flats. As the bureaucracy planned for the centennial, the American Institute of Architects (AIA) joined the fray. AIA leaders envisioned the nation’s capital as the perfect place for the group to express the ideals of the City Beautiful movement promoted by the 1893 World’s Columbian Exposition in Chicago. The architect of this pivotal fair designed Beaux Arts Classical architecture in a grand and ordered civic space.
When the Senate Commission was formed in 1901 to explore and plan the design of the city, the project then encompassed the historic core. The illustrious committee was comprised of Daniel Burnham, a visionary of the World’s Columbian Exposition, as well as landscape architect Frederick Law Olmsted, Jr., architect Charles F.McKim, and sculptor Augustus St. Gaudens.
Foremost in the minds of these men was the amazing foresight and genius of Pierre L’Enfant. The committee lamented the fragmented Mall marred by a railroad station and focused upon restoring it to the uninterrupted greensward envisioned by L’Enfant. In total, the forward-looking plans made by the McMillan Commission called for: re-landscaping the ceremonial core, consisting of the Capitol Grounds and Mall, including new extensions west and south of the Washington Monument; consolidating city railways and alleviating at-grade crossings; clearing slums; designing a coordinated municipal office complex in the triangle formed by Pennsylvanian Avenue, 15th Street, and the Mall, and establishing a comprehensive recreation and park system that would preserve the ring of Civil War fortifications around the city.
To protect the new goals introduced by the McMillan study, the AIA appealed to President Theodore Roosevelt to form a fine arts commission. Established by Congress in 1910 during the Taft Administration, the Commission of Fine Arts (CFA) was created as a consulting organization to the government on the design of bridges, parks, paintings, and other artistic matters; an executive order later that year added the design review of all public buildings.
Influenced by the designs of several European cities and 18th century gardens such as France’s Palace of Versailles, the plan of Washington, DC was symbolic and innovative for the new nation. Only limited changes were made to the historic city-bounded by Florida Avenue on the north and the waterways on the east, west and south-until after the Civil War. The foremost manipulation of L’Enfant’s plan began in the 19th century, and was codified in 1901 when the McMillan Commission directed urban improvements that resulted in the most elegant example of City Beautiful tenets in the nation. L’Enfant’s plan was magnified and expanded during the early decades of the 20th century with the reclamation of land for waterfront parks, parkways, an improved Mall and new monuments and vistas. Two hundred years since its design, the integrity of the plan of Washington is largely unimpaired-boasting a legal enforced height restriction, landscaped parks, wide avenues, and open space allowing intended vistas. Constant vigilance is needed by the agencies responsible for design review, it their charge to continue the vision of L’Enfant.

鹦鹉螺(中文版)

鹦鹉螺属于头足纲中的四鳃类。古老的头足类也都像鹦鹉螺一样，有不同形状的贝壳。但到现在它们大都已经灭绝，唯一剩下的只有在海底生活的鹦鹉螺了，所以鹦鹉螺是一种“活化石”，属于国家保护动物，很久以来便是动物进化系统研究中的很有价值的材料之一。

　　鹦鹉螺是一种底栖性的动物，平时在海底爬行，偶然也漂浮在海中游泳。它的游泳方式跟乌贼相仿，是利用它的两片互相包被的漏斗喷水进行的。鹦鹉螺的触手数目很多，一共有90个。其中有两个合在一起变得很肥厚，当肉体缩到贝壳里的时候，用它盖住壳口，这与腹足类的厣的作用相当。

　　世界上生活的鹦鹉螺一共只有3种，数量也不多。它们的贝壳很好看，珍珠层很厚，可供玩赏或制造工艺品。

海底“天文学家”——鹦鹉螺

鹦鹉螺属软体动物头足纲，早在距今5亿多年前就出现了，分布在全球范围内，有350多种，与它同类的章鱼、鱿鱼、乌贼等在进化发展中身体发生了很大的变化，身体外的壳有的转入身体里面，如乌贼。有的仅仅留下一层胶质的薄膜，如鱿鱼。还有的壳已经消失了，如章鱼。它们游泳的速度加快了，可是惟独鹦鹉螺的壳自从演变成现在的模样就没有多大变化，只有6种，所以它是现存软体动物中最古老、最低等的种类，也是研究生物进化、古生物与古气候的重要材料，有“活化石”之称。稍有变化的是生活的环境从原来的浅海移居到200~400米的深海中。白天在水下，晚间浮出水面。
鹦鹉螺的足在头部，所以称头足类，依靠身体前端的几十根触手搅动水流进食，如果前后水平运动，则是靠吸水排水；鹦鹉螺上下垂直运动则靠的是壳内众多的气室，气室间有一根充满血液的连接小管，充气和排气，充满气体就上升，排除气体就下沉。所以说鹦鹉螺的结构设计是自然界最奇妙的设计。
鹦鹉螺的气室是一间一间形成的，最外边的一间是最新的、最大的。到目前为止最多的有38间。鹦鹉螺壳的构造不仅美丽而且坚固，它的曲线是一种对数函数，能够承受2000千克的压力。
鹦鹉螺气室上有许多环纹称为生长线。同一个时代的鹦鹉螺化石，其生长线数目是一样的。但是，这些生长线数目随年代的不同而变化，研究化石的鹦鹉螺，从远古到现在，生长线数目越来越多。据研究，生长线的数目与当时月亮绕地球一周所需要的天数是一致的，远古时期，月亮距离地球近，绕地球一周的天数少，所以生长线的数目少，现在的鹦鹉螺的生长线有30条，正好与现在月亮绕地球一圈所用的时间一致。鹦鹉螺壳记录了月亮与地球的旋转的关系，所以鹦鹉螺有“海底天文学家”的美誉。鹦鹉螺分布于马来群岛、台湾海峡和南海诸岛。

鹦鹉入海飞
在距今4亿4千万年到5亿年前，有一时期，独霸海洋的曾经是一种体型很大的鹦鹉螺。鹦鹉螺是软体动物，柔软的身体外面包着外壳，外壳又厚又大，从背面向腹面卷成螺旋型，左右对称，壳的外面有均匀的条纹。活的鹦鹉螺全身闪耀着白色、灰色、橘红色的光泽，在海洋游泳时，头和腕完全伸出壳外，壳口向下，像一只翩翩飞舞的鹦鹉。从古代到中生代，头足类十分繁盛，在古生物学中头足纲被划分为：鹦鹉螺亚纲、杆石亚纲菊石亚纲和鞘形亚纲，人们根据壳的形状，体管内沉积物特点、体管类型等，把鹦鹉螺划分为四个超目，是：直角石超目、内角石超目、珠角石超目和鹦鹉螺超目。前三个超目是已经灭绝的类群，惟独鹦鹉螺超目一直残存到现在。鹦鹉螺在软体动物中是进化的比较完善的一个类群，所以在它的时期可以为所欲为。它们以其它小动物为食。他们有明显的头部，眼睛很大，视力很好。头的前端中央有口，口内有坚硬的颚，能够咀嚼很硬的东西。口的周围有几十条细小的腕，用来探索环境、捕捉食物也用来在海底爬行。主要的运动方式和乌贼差不多。鹦鹉螺在5亿多年前就出现了，早出现的种类体型小，数量不多，构造比较简单，4亿4千万年前，这个华丽的家族极其繁盛，现在的化石品种已达2500多种（不包括菊石）身体也大的惊人，最大的鹦鹉螺化石是在奥陶纪地层中发现的长达10多米。在四亿多年前仍然很多，到了三亿5千万年前开始迅速衰落，现在仅仅生存有4种 ，是著名的活化石。运气好的话只有在印度洋和菲律宾不超过600米深度的温暖海洋，探海的人可以极其幸运的捕捞到，进行饲养，很难活到一年。我国的鹦鹉螺壳来源全部来自西沙群岛、南沙群岛和海南岛，数量很多。也从一个侧面反映了我国的鹦鹉螺种群在逐步萎缩，现在4种鹦鹉螺是世界级的重点保护动物，我国的鹦鹉螺品种的研究价值比较特殊，是那3种无法代替的，所以我国的鹦鹉螺要严加保护！

About nautilus and king nautilus
By 1986, Saunders and I had collected tissue from nautiluses around Fiji, Samoa, Australia, New Guinea, the Philippines, Palau, and New Caledonia. Two independent sequencings of their genes yielded the same remarkable result there are only two distinct groups of nautiluses. One is composed of the king nautilus, which appears to have descended from the chambered nautilus about 15 million years ago; the other group is composed of all the other so-called nautilus species.
If the genetic evidence is accepted, it means that the long-agreed classification of the living species has crumbled. The king nautilus represents a different genus altogether, while the differences in shell morphology of the other “species” seem to be useless in telling them apart. We had gone from 11 living species belonging to one genus–Nautilus–to two genera, Nautilus and our newly recognized genus, with only two or three species between them. We gave the king nautilus a new scientific name, Allonautilus, which is Latin for “other nautilus.”
These surprising results made us wonder if nautiloid fossils might also have some secrets to reveal. Unable to study extinct nautiloid DNA, we had to figure out a new way to classify these animals based on their shells alone. Previous studies of nautiloids had classified them on relatively few features, and we hoped that we might find more to examine. Luckily for us, just such a trove of distinctive new characters had been uncovered by Neil Landman of the American Museum of Natural History in New York.
The chambered nautilus hatches at a very large size: it emerges from its egg with seven fully formed chambers and a shell diameter of more than an inch, making it the largest invertebrate at hatching in the world. (Indeed, it may have been this trait that allowed it to survive the great Cretaceous mass extinction, for the nautilus appears to lay its eggs in very deep water, where they take a year to hatch. Juveniles or unhatched eggs might have survived in a deep refuge when the great comet ending the age of dinosaurs, 65 million years ago, turned all the shallower oceanic regions into a toxic, heated cauldron of extinction.) When a living chambered nautilus emerges from its egg, it stops growing temporarily, and this pause leaves a distinct groove in its shell. Since the shell wraps around itself as it grows, these earliest stages are always preserved in the middle. Landman began dissecting fossils to see if similar marks were found in extinct species as well. He discovered that not only did these marks occur, but many other features also.
Saunders and I combined Landman’s new characters with the classical ones and then began to study their occurrence in living and extinct nautiloids. Both of us had been taught that present-day nautiluses are the most recently evolved of the 10,000 nautiloids that have swum through the oceans over the past 500 million years. Thus we expected them to have a lot of features that had evolved relatively recently. To our surprise, we found that today’s chambered nautilus appears to be extremely primitive–rather than being a descendant of some fairly recently evolved nautiloid, the chambered nautilus evolved much earlier. It may even be the ancestor of most of the nautiloids present on our planet for the last 75 to 100 million years.

有关鹦鹉螺的完整介绍！http://www.findarticles.com/cf_0/m1511/n3_v19/20324745/p1/article.jhtml?term=

mangrove:红树林
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什么是红树林？它有什么作用？
红树林是唯一能种植在海滩上，耐海水浸渍的树木。老厦门们对它并不陌生，它就是过去海边常见的“海 加定”。红树林是热带、亚热带潮间带特有的木本植物群落。科学研究表明：红树林生态系统是世界上高生产力的生态系统之一。
　　红树林对近海渔业有积极的促进作用，是海区生物能源的重要供应者。红树林区是 多种鱼、虾和蟹等经济海产隐蔽、生长和繁殖的良好场所。红树林作为沿海防护林的第一道屏障，对风浪具有强大的“消能”作用，同时其发达的根系，具有很强的固土能力， 对固堤护岸、保护沿海的各种设施有很好的作用。红树林有防治污染、过滤陆源入海污染物、减少海域赤潮发生的作用。我市红树林处在九龙江出口处，保护红树林直接关系 到保护我们的母亲河。此外，红树林还有美化环境及提供林产自然资源等多种作用。其 经济效益、社会效益和生态效益十分显著。科氏力 （coriolis force）  
地球自转会带来一种力，科学家称之为科里奥利力（简称科氏力，是一种非惯性参照系的惯性力）。相对于推或者拉产生的力而言，科氏力并不是一个“真实的”力，但是它的力量确实非常强大，强大到可以造就台风。

在旋转的的地球上，流体运动始终受到科氏力的作用，气象学上又称之为地转偏向力。对于大尺度大 气运动，科氏力具有十分重要的意义。

由於地球自轉的關係，空氣快一開始運動即無法與地球自轉系統同步，因而產生偏轉現象。舉例來說，如果有甲、乙二人站在轉盤上，甲自轉動中心平拋出一球，給位於轉盤邊緣上的乙。站在盤外的丙，所看到求的飛行方向是直線，然而就乙和球的相對位置而言，乙所看到球的移動路徑卻是拋物線。

假設有一顆砲彈從北極點發射出去，如果地球不會自轉，那麼砲彈的飛行軌跡，從空中鳥瞰，應該是一直線。但是，事實上地球會自轉，因此，隨著地球的自轉，砲彈在空中飛行的軌跡，如果站在北極點看過去，是不斷偏右的。這就是科氏力的原理。
这段话基本就是听力原文。
然后就是如何影响洋流，科学家可以利用它来预测。

再摘录两段
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⊙為什麼赤道地區不能形成颱風？
因為科氏力能使氣流轉彎，但赤道地區沒有科氏力，所以雖然赤道地區很熱，但仍無法形成颱風，必須在緯度５度以上，才有足夠的科氏力。

在横渡大西洋前往圣萨尔瓦多的时候，哥伦布发现蔚蓝色的海洋中，有一道深蓝色的河流自东向西流动着。这时，帆船快速地随波漂流。哥伦布在日记中写道：“我注意到海水明显地自东向西流动，好像上帝驱使的一样。”

其实，哥伦布看到的那道深蓝色的“河流”就是海流。海流是海水大规模相对稳定的运动，它遍及世界各个大洋，组成一个个好似封闭的循环。海流的运动有很多奇怪的地方。

首先，它运动的方向会在惯性作用下发生偏转。这个现象是物理学家科里奥利首先提出来的，人们就称这种力叫“科氏力”。

假设在没有科氏力作用下，海洋中运动的船只会沿着直线行进。然而，在科氏力作用下，船只的前进方向马上就改变了。由于我们这个装置是模拟地球北半球的运动，所以，偏转的方向会向右。

What is p53 ?

After the identification of the p53 protein and the subsequent cloning of p53 genes from several species, early observations suggested that p53 may function as an oncogene, because overexpression of p53 appeared to cause oncogenic transformation of cells. In the late 1980s, however, several critical discoveries defined the normal function of p53 to be anti-oncogenic. Wild-type p53 genes, when introduced into cells, were found to be growth suppressive. The screening of DNA from colon cancer patients revealed that p53 mutations occur with unusually high frequency in tumor tissue, an observation that was extended to most of the other major forms of human cancer. Indeed, members of Li-Fraumeni cancer-prone families were shown to carry germ-line p53 mutations. The importance of these observations was underscored by the finding that mice that are homozygous null for p53, although developmentally competent, are highly predisposed to tumors.

The functional character of the p53 protein was determined by experiments showing that p53 contains a strong transcriptional activation domain within its amino terminus and that it is a tetrameric, sequence-specific DNA-biding protein with a defined cognate binding site containing two copies of the 10-mer (5′-RRRCA/TT/AGYYY-3′). Although the p53 protein acts as a transcriptional activator of genes containing p53-binding sites, it is also capable of strongly inhibiting transcription from many genes lacking p53-binding sites. Several oncogenic DNA viruses express viral gene products that associate with and inhibit the trans-activation function of p53, notably SV40 large T antigen, the adenovirus E1B 55-kD protein, and the E6 protein of oncogenic forms of human papillomavirus (HPV E6). In cells, p53 can associate with a 90-kD protein, identified as the product of the mdm-2 oncogene, which is amplified in some types of tumors. When bound to mdm-2, p53 can no longer function as an activator of transcription.

p53 plays multiple roles in cells. Expression of high levels of wild-type (but not mutant) p53 has two outcomes: cell cycle arrest or apoptosis. The observation that DNA-damaging agents induce levels of p53 in cells led to the definition of p53 as a checkpoint factor, akin, perhaps, to the product of the fad9 gene in yeast. While dispensable for viability, in response to genotoxic stress, p53 acts as an “emergency brake” inducing either arrest or apoptosis, protecting the genome from accumulating excess mutations. Consistent with this notion, cells lacking p53 were shown to be genetically unstable and thus more prone to tumors.

(中文版)

p53是存在人體細胞內的一種抗癌白質，它有抑制細胞生長及維持遺傳物質完整性的功能。事實上，半數以上的癌症細胞內都有p53的突變，可見其在細胞生長控制上扮演了重要的角色。在正常狀況下，p53的半衰期約只有30分鐘，相當不穩定；然而當細胞經紫外線，離子化射線(如X光，伽傌照射)，或當細胞缺氧、缺養時，p53被活化，同時它的穩定性提高，造成細胞內的p53大量增加，除了上述刺激外，化學治療上常用的藥物也有同效。這種p53的活化與增加常導致兩種可能的結果：一是細胞長停止在G1或G2期；另一是細胞採自殺行為（apoptosis)而死亡。細胞由此得以修補損壞(前者)，或過度受損的細胞得以從人體除去(後者)。這種依賴p53的”自衛措施”在一些細胞中常因p53的突變而失去功能，使得這些有”缺陷”的細胞能繼續不受控制的生長分裂，導致突變的累積和癌症的生長。

雖然環境因子影響p53活性及穩定性的事實已知已久，其間的分子機轉仍不清楚。蛋白質的磷酸化(phosphorylation)一向被認為在訊息傳遞上扮演重要的角色。事實上，經由我們及其他實驗室的研究發現，p53在經過紫外線，伽傌射線照射後，其N端的數個胺基酸(第15，20，33，37)有磷酸化的現象。這種磷酸化發生極為快速，幾乎是在照射後數分鐘內即已產生，而持續多久則視胺基酸位置、刺激型態，及細胞種類而異。至於這些磷酸化與p53的反應之關聯性則仍有待證明。最近我們發現有兩個在細胞分裂(Cell cycle)的檢查點(checkpoint)上扮演著重要調控功能的磷酸化酵素(kinase) hCHK1，CHK2可以有效的磷酸化p53。有趣的是，磷酸化的胺基酸中包括了那些可以被紫外線、伽傌線引起的位置，即第15，20及37胺基酸。我們正著手研究可能的CHKs的上游分子及p53在CHKs磷酸化後功能之變化。此外， 不同的環境因子與p53聯繫的方式可能各異，有些可能透過磷酸化以外的方式進行。 我們希望能先定出p53序列中與環境因子互動有關的區域(domain)，再由此找出與調節p53穩定性有關的機制及分子。

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艺术流派
現代藝術(Modernism)野獸派 (Fauvism) 立體派 (Cubism) 表現派 (Expressionism)
機械主義(The Age of Machinery) 未來派(Futurism) 達達派(Dada)
超現實主義(Surrealism)
野獸派 (Fauvism)

印象派發展到後期, 尤其進入了後期印象派(Post Impressionism)之後, 藝術家們的思想方式越來越主觀, 也可以說越來越有個人的特色. 印象派兩腳跨在十九及二十世紀的鴻溝上, 將藝術由古典拉進了現代. 接下來要介紹的野獸派(Faurism)就是純純正正的二十世紀的現代藝術. 1905年, 馬蒂斯(Henri Matisse)與他的朋友佛洛明克(Maurice de Vlaminck)和戴倫(Andre Derain)在法國巴黎的藝術中心-蒙馬特舉行的秋季沙龍中, 展出了一系列色彩強烈, 畫面單純的畫作. 藝術評論家路易士牟雪爾(Louis Vauxcelles)看見一件古典雕刻的周圍掛了許多如此的作品, 忍不住說: 就像古典雕刻家(Donatello)在野獸群中(“parmi les fauves” among the wild beasts). Les fauves 就是法文中的野獸群, 馬蒂斯一群人也認為他們這種突破傳統的勇猛畫風, 的確帶有一點野獸的味道, 於是”野獸派”重此訂名. 野獸派對西洋藝術貢獻有絕對性的影響, 單純的線條, 鮮豔奪目的色彩是受到了梵谷的影響. 脫離自然的模仿, 從塞尚的畫中野獸群們強調心中主觀的認知而忽略眼中看見的客觀形體而發揮了炙熱的創造力. 野獸派帶領著西洋繪畫朝向更深入的”純粹造型”方向表現.

立體派 (Cubism)

野獸派在馬蒂斯的帶領之下, 橫衝直撞的在歐洲激出了巨大的火花. 但野獸派的時間卻不長, 大約十年後, 西班牙誕生的畢卡索(Pablo Picasso)所創的立體派(Cubism)出現了. 從此, 野獸派之後, 立體派成為最具影響力及革命性的畫派之一, 世界從此看起來也不再一樣了. 畢卡索這位現代藝術最重要的宗師, 他出現的前, 後百年的西方藝術各流派, 不是不是被他所吸收, 就是被他所影響. 今天所要介紹的就是他-所創造出來的-立體派. 立體派的繪畫理論是塞尚(Paul Cezanne)所說的:”自然的一切, 都可以從球形, 圓錐形, 圓筒形去求得”. 科學理論即是物理學的:”物體的演化都是從原本物體的邊與角簡化而來的”. 立體派的畫家們把他們所畫的物體打破成許多不同的小平面, 在同時表現出物體不同的外觀. 基於以上觀點, 立體派的畫家開始重視直線, 忽視曲線, 運用基本形體開始幾何學上的構圖. 1908年, 馬蒂斯看到這些奇妙的繪畫說:這應該叫做立體派了”. 立體派從此打響了名號. 立體派受黑人雕刻及東方繪畫的影響, 他們強調畫中要把物體的長, 寬, 高, 深度在同時表現出來. 他們不在由平面看物體而是由四面八方的觀察, 然後將物體打破支解, 再由畫家的主觀意識將碎片整理湊合, 完成一個完整的藝術.

表現派 (Expressionism)

野獸派之後, 法國有畢卡索為首的立體主義, 幾乎在同時的德國則有表現派(Expressionism)興起. 1909年, 表現派的畫家們首次在德國的德勒斯城組織團體”橋派”. 1911年, 康丁斯基(Wassily Kandinsky)和馬爾克(Franz Marc)在德國慕尼黑地區組織”黑騎士”的美術團體, 標榜表現主義從事繪畫創作. 依年代來看, 正值第一次世界大戰後期, 表現派的畫家們看見戰爭的殘酷, 一切的一切被戰爭摧毀. 因此, 他們開始批判的角度來探討物體的本質, 否認眼睛所看到物體的姿態, 而注重物體在眼中所表現出來的樣子. 因為每個不同的人所看見的物體會有不同的體認, 自然每個人所描述及表現的方法也不同, 所以表現派是極端主觀的個人主義, 他們寫意而不寫實, 象徵而不表象. 表現派與野獸派一樣注重使用鮮豔的色彩, 當然與野獸們不同的是他們絕對不會讓你輕易了解, 因為每個人不會對同一件物體有完全一樣的看法, 你不是他. 雖然表現派沒有如野獸派與表現派出現特別了不起的人物, 但他們對二十世紀中期以後的現代抽象主義(Non-figurative Art)具有深刻的影響. 對不起, 因為現代的抽象主義, 你更看不懂.

機械主義(The Age of Machinery)

接下來要介紹一下機械主義(The Age of Machinery)及未來派(Futurism). 機械主義與未來派幾乎是在同一個時代, 當時立體派沒落, 在德國有表現派興起, 法國有機械主義, 義大利則有未來派. 機械主義代表人物只有勒澤一人, 有些人乾脆把他歸入立體派中, 但再西洋藝術史中也可以說是不可忽略的一個流派. 機械主義的畫家由機械上取得靈感, 加上塞尚的理論:”自然的一切, 都可以由球形, 圓錐形和圓筒形去求得. ” 機械主義傳承了印象派及野受派的精華用原色作畫, 事先不加調配. 機械主義的畫家也不喜歡在畫上加上特別的筆觸, 只用平塗法作畫. 如此, 機械主義的畫看起來樸素且堅實, 運用強烈的色彩對比, 表現一種明朗生動的感覺.

未來派(Futurism)

在法國的未來派是一個有預先組織的畫派, 他們把畫派的中心思想及名稱都想好了並發表後, 才開始依照準則作畫. 未來派的準則簡單的來說就是:”動就是美”. 他們認為, 一切的一切在未來而否認過去. 他們認為要不停的動, 才能擺脫過去, 迎向未來. 未來派表現”動”的方法大多是用物體的連續動作. 好像攝影時使用慢速快門, 了解攝影的人都知道, 在攝影中要表現動作(movement)時, 有兩個選擇, 一是用快速快門(通常在1/500秒以上)使物體動態凝結, 二是用慢速快門(通常在1/30秒以下)使物體在底片上留下動態軌跡. 所以未來派所表現的不是現在式, 不是過去式, 更不是未來式, 而是現在進行式(加-ing就對啦!). 雖然未來派只有短短的五, 六年, 但是這個觀念影響了之後的達達派(Dada)及現代抽象藝術, 他們比未來派更否定過去, 保證你看不懂.

達達派(Dada)

第一次世界大戰後, 達達派(Dada)由瑞士向歐洲蔓延了出來. 當時的環境是: 後期印象派(Post Impressionism)到了後期, 其他還有立體派, 表現派, 未來派等畫派在歐洲盤據地盤, 但每一個都逃不出達達派的批判. 因為達達派如表現派般厭惡戰爭而厭惡過去, 但程度上比未來派還要激進. 他們大膽的摧毀一切舊有的傳統, 而採取無理性的表現方式. 達達派的表現方式著重在天然形成與自由塗寫. 他們喜歡用不同的材料用自然排列的方式成為一個新的藝術. 例如, 把色紙剪成塊狀(有一點兒像野獸派大師馬蒂斯後期的表現方法)然後讓他們自由飄散在地上, 而取得靈感. 達達派的文學家把報紙的字母寫下, 然後抖動他們再依字母的自然排列成了一首新詩(這又有點像台灣的乩童在上身後鬼畫符一番, 之後再由旁人解說). 所以達達派的創作是象徵的且無定形的呈現(因為他們也不知道抖完後會成什麼樣子). 我想達達派最大的成就, 應該是讓當時的人有完全逆向思考的機會. 大戰結束後, 德國, 法國, 甚至隔海的美國都有不少人從事此風格的創作.

超現實主義(Surrealism)

第一次世界大戰完畢後的幾年, 人們開始懷疑理性主義, 雖理性主義然使歐洲的文化, 政治達到頂峰但還是發生了恐怖一次大戰. 雖然達達派(Dada)的藝術風靡了當時的歐洲畫壇. 但是把印了字的紙片灑在地上作詩, 似乎太過消極了. 超現實主義(Surrealism)這時開始萌芽了. 1924年, 超現實主義的創始人, 也是達達派的詩人與評論家-安德烈布爾頓發表了”超現實主義宣言”(The Surrealist Manifesto). 宣言中指出: 超現實主義是結合了意識的和無意識的精神領域在每天的現實生活中而完成世界的美夢與幻想. 簡單的說, 超現實主義不但重視人類意識的思考, 另外更重視下意識的範疇. 他們用科學的方法研究人在無意中畫出的圖畫, 信手寫出的字, 小孩或瘋子的圖畫, 結合心理學與精神病學的原理, 配合上人的夢境與幻想. 結論是: 美是在解放了的意識中那些不可思議的幻象與夢境. 所以超現實主義是一種超理性, 超意識的藝術. 超現實主義的畫家不受理性主義的限制而憑本能及想像, 表現超現實的題材. 他們自由自在的生活在一種時空交錯的空間, 不受空間與時間的束縛, 表現出比現實世界更真實更有意義. 超現實主義首先在法國展開, 立即受西班牙畫家的歡迎, 很快普及到全世界. 而原本是單純的美術改革運動, 不久也影響到了文學, 雕刻, 戲劇, 戲劇舞台, 電影, 建築等其它的應用藝術, 所以超現實主義可以說是影響全世界的新文藝運動. 但在第二次世界大戰時, 大量的藝術家遷往美國, 同時影響美國超現實主義的風行. 1945年後”新具象”在藝術之都巴黎興起, 超現實主義才漸漸沒落

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背景知识: 地球的旋转时间变短
We have been talking about some of the effects that the human beings had on the earth. One you may not be aware of is that we actually begin to change the length of the day. In the other way to say, one day is the amount of time the earth needs to spin completely around an axis, the imaginary line around the center of the earth, from the north to the south. And of course there are a lot of physical causes that can affect the speed of the earth’s rotation, but there was only one that is direct result of the human activity. Since 1950, human beings have built about ten thousand artificial reservoirs all over the world. These reservoirs have redistributed tremendous amount of the earth water. When they are used to be in the area near the equator, the imaginary line surround the middle of the earth, it’s now the reservoirs in the areas of different latitudes. The latitude matters because, well, thinking the earth and axis, the equator contains the areas on the earth that are the farthest away from axis. So water has been redistributed from the equator regions, then wherever the water is, to it’s close to the earth axis. It’s like when ice skaters perform spins when those skaters put their arms enclose to their bodies, they spin faster. So the earth is spinning faster because the reservoirs have redistributed the water close to its axis. And because the earth was spinning faster, since 1950 the length of day has decreased by about 8 millionth of second. I know that doesn’t sound like much but significant in that this is the first time that human beings ever had measurable affect on the earth’s motion.

背景知识: 潮汐发电
凡在海边上生活过的人都知道，海水时进时退，海面时涨时落。海水的这种自然涨落现象就是人们常说的的潮汐。潮汐是由月球的引潮力可使海面升高0.246米，在两者的共同作用下，潮汐的最大潮差为8.9米;北美芬迪湾蒙克顿港最大潮差竟达19米.据计算,世界海洋潮汐能蕴藏量约为27亿千瓦,若全部转换成电能,每年发电量大约为1.2万亿度。潮汐发电严格地讲应称为“潮汐能发电”，潮汐能发电仅是海洋能发电的一种，但是它是海洋能利用中发展最早、规模最大、技术较成熟的一种。

现代海洋能源开发主要就是指利用海洋能发电。利用海洋能发电的方式很多，其中包括波力发电、潮汐发电、潮流发电、海水温差发电和海水含盐浓度差发电等，而国内外已开发利用海洋能发电主要是潮汐发电。由于潮汐发电的开发成本较高和技术上的原因，所以发展不快。
　　潮汐发电与水力发电的原理相似，它是利用潮水涨、落产生的水位差所具有势能来发电的，也就是把海水涨、落潮的能量变为机械能，再把机械能转变为电能（发电）的过程。具体地说，潮汐发电就是在海湾或有潮汐的河口建一拦水堤坝，将海湾或河口与海洋隔开构成水库，再在坝内或坝房安装水轮发电机组，然后利用潮汐涨落时海水位的升降，使海水通过轮机转动水轮发电机组发电。
　　由于潮水的流动与河水的流动不同，它是不断变换方向的，因此就使得潮汐发电出现了不同的型式，例如：①单库单向型，只能在落潮时发电。②单库双向型：在涨、落潮时都能发电。③双库双向型：可以连续发电，但经济上不合算，未见实际应用。 4潮汐发电的实际应用应首推1912年在德国的胡苏姆兴建的一座小型潮汐电站，由此开始把潮汐发电的理想变为现实。世界上第一座具有经济价值，而且也是目前世界上最大的潮汐发电站，是1966年在法国西部沿海建造的朗斯洛潮汐电站，它使潮汐电站进入了实用阶段，其装机容量为24千瓦，年均发电量为5.44亿度。1968年原苏联巴伦支海建成的基斯洛潮汐电站，其总装机容量为800千瓦，年发电量为230万度。中国沿海已建成9座小型潮汐电站，1980年建成的江厦潮汐电站是我国第一座双向潮汐电站，也是目前世界上较大的一座双向潮汐电站，其总机容量为3200千瓦，年发电量为1070万度。
蜘蛛丝军事用途
神奇的“生物钢”
　　生物钢指的是羊奶钢，也指牛奶钢。羊奶与牛奶，本来与钢铁风马牛不相及，但科学家却将它们巧妙地结合起来了。
　　1997年初，美国生物学家安妮·穆尔发现，在美国南部有一种称为“黑寡妇”的蜘蛛，它吐出的丝比现在所知道的任何蜘蛛丝的强度都高，而且这种蜘蛛可以吐出两种不同类型的丝织成蜘蛛网，第一种丝在拉断之前，可以延伸27％，它的强度竟达到其他蜘蛛丝的2倍；第二种丝在拉断之前很少延伸，却具有很高的防断裂强度，由这种蜘蛛丝织成的布，比制造防弹背心所用的纤维的强度还高得多。“黑寡妇”蜘蛛丝的优良性能，很快引起科学家兴趣，他们设想，要是有一种办法能生产像蜘蛛丝那样的高强度纤维该多好。
　　科学家想到让牛奶的蛋白基因中含有“黑寡妇”蜘蛛丝的蛋白基因，于是就先找山羊进行转基因的科学实验。让山羊与“黑寡妇”蜘蛛“联姻”，将蜘蛛蛋白基因，注入一只经过特殊培育的褐色山羊体内，在这只山羊产下的奶中，有大量柔滑的蛋白质纤维，提取这些纤维，就可以生产衣服。
　　实践表明，由转基因羊奶纤维织出的布，比防弹衣的强度还大十几倍。这种超强坚韧的物质，是阻挡枪弹射击的理想材料，也可以用来制造坦克、飞机与装甲车，以及作为军事建筑物的理想“防弹衣”。根据国外的资料报道，一只羊每月产下的奶提取的纤维，可以制成一件防弹背心。美国正在研究利用蜘蛛丝的专家称，利用这种纤维制成的2.5厘米粗的绳子，足以让一架准备着陆的战斗机完全停下来。
　　科学家给这种物质取名叫“生物钢”。羊奶与牛奶变成的“生物钢”，不仅有钢铁的强度，而且还可以生物降解，不会带来环境污染，可替代引起白色污染的高强度包装塑料和商业用渔网，以及用于医学方面的手术线或人造肌肤。科学家设想，如果让转基因的山羊大量繁殖，就会生产出大量的生物钢用于工农业生产与国防战略，考虑到山羊对植被的破坏性，对牛进行转基因实验的前途更为广阔，一头牛的产奶量比一只山羊的产奶量高得多。

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