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2.1.6 Concrete
V1 by jaejonng 710
第一段介绍concrete的作用，处理方法（这里有题，原文改写）
第二段说细菌对concrete应该有好的影响，但是细菌的存货时间很短，只有几天，所以其实是没有用的。
然后有个J做了一个实验，证明细菌对concrete还是有用的，因为数量猛增，而且其实可以活的很长，几个月甚至几年。
接下去又对J的实验部分否定，提出了另一个approach（很短，属于延伸部分），说在吧细菌加到concrete之前可以先做一个处理，这里有类比题，问这个处理和选项的哪个相似。

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2.1.7 生物种群的多样性（我觉得这两个jj不是一篇文章的，囧）
V1 by沫澧 700
对比死水和活水里生物种群的多样性(这篇很坑爹。。。这篇生物专业术语特别多) 说活水和死水里生物种群的多样性是不一样的，但是为什么捏
第二段说在活水里可能是因为物种繁殖的速度决定了这个物种是否能存活，繁殖速度足够快（我猜是说不能在还没生出一堆小宝宝之前就被悲催的冲走了），才能在活水里存活下来。如果这是唯一的原因的话，死水里的种群多样性应该高于活水，但是捏，你懂得，没有这么简单。。。科学家们又发现，一些死水里的种群还不如活水多，介个又是为什么捏~ 第三段来鸟~~
第三段科学家又说，这可能是因为死水里捕食者predator多，使得死水里生物种类少。而活水里捕食者少，各种群之间主要为了争夺有限的资源而发生矛盾，限制了他们的数量
V2 by jessiacacai
关于ecosystem，很长的一段。
很难确定在ecosystem的管理中怎么做才是合适的，比如是否应该用species diversity作为indicator of a healthy system. 一贯认为，越diverse越好，但是也存在一些其他情况。举了个例子，某E做的研究，说一个pristine的环境是low diverse，而另一个环境加入了exotic species而增加了diversity.
考题：
E的研究说明了什么？lz选的答案是low diversity好
我的材料：（配图一张，是另一份材料的）
Natural aquatic habitats include ponds, lakes, rivers, streams, springs, estuaries, bays, and various types of wetlands. Some of these habitats are shallow and others deep, some are cold-water and others warm-water, some are freshwater and others saltwater, and some have high oxygen levels and others little oxygen.
Aquatic habitats can be classified as:
•        non-flowing waters like lakes and ponds,
•        slowly-flowing waters like marshes and swamps, and
•        flowing waters like rivers and streams.
Aquatic ecosystems consist of living organisms together with their nonliving habitat. Although the ecosystem concept is a useful one, the exact definition is somewhat arbitrary. For example, an ecosystem can range in size from a small water droplet to the vast oceanic ecosystem, and the upper, lower, and horizontal boundaries are often not well established.

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2.1.8 农作物
By lesezeichen 680
篇说农作物的，但是我不懂那个单词我就不误导了，总之很长的文章，好几段。一段先说了这个p开头的单词的作物（也许是野生植物，或者说多年生，因为是和crop和annualy做比较的）和普通我们种植的作物的区别，大概就是不需要施肥也不会遭虫子之类的。第二段就说了一下我们老祖宗是怎么慢慢开始农作物耕种的，大概是解释为什么有的就变成了我们的水稻玉米之类的，有的就还是野生的没人要的吧，嗨~，然后后面第三段，或者甚至第四段就开始讲了各种原理，总之就是再说这种p植物可以被种植的feasibility吧。
我的材料：
我觉得这篇文章讲的可能是植物驯化Corp domestication，待验证。
（以下是两种被驯化的P植物，待确认）
      Proso millet (Panicum miliaceum) is also known as common millet, hog millet or white millet. Both the wild ancestor and the location of domestication of proso millet are unknown, but it first appears as a crop in both Transcaucasia and China about 7,000 years ago, suggesting that it may have been domesticated independently in each area. It is still extensively cultivated in India, Russia, Ukraine, the Middle East, Turkey and Romania. In the United States, proso is mainly grown for birdseed. It is sold as health food and due to its lack of gluten it can be included in the diets of people who cannot tolerate wheat.
Pearl millet (Pennisetum glaucum) is the most widely grown type of millet. Grown in Africa and the Indian subcontinent since prehistoric times, it is generally accepted that pearl millet originated in Africa and was subsequently introduced into India. The earliest archaeological records in India date to 2000 BC, so domestication in Africa must have taken place earlier. Its origin has been traced to tropical Africa. The center of diversity for the crop is in the Sahel zone of West Africa. Cultivation subsequently spread to east and southern Africa, and southern Asia. Records exist for cultivation of pearl millet in the United States in the 1850s, and the crop was introduced into Brazil in the 1960s.
植物驯化的知识：
瓦维洛夫承认他的“植物地理学分化”说并不尽如理想，又创造了一个“次中心”的概念，以说明多样性中心并不等于起源中心这一事实，而实际上次中心的变异往往比真正的驯化中心还要大。真正的中心是可以逐个予以证实的。他还提出一个“次生作物”（secondary crop)的概念，说次生作物是从古老的杂草或原始作物衍生而来，他以黑麦和燕麦为例，当农业从近东中心和地中海中心向北欧传播时，杂草黑麦和杂草燕麦就作为小麦田及大麦田的“杂质”一起跟随着传播，在这个过程中，黑麦与燕麦远离它们的故乡，发展成为驯化种系，即次生作物。Edgar

Anderson (1954)深受瓦维洛夫的影响，认为农作物常常可以由杂草衍生而来。
Zeven和Zhykovsky

汇总各家学说，把栽培植物起源的顺序作了如下归纳：
      1.人们采集野生植物。
      2.野生植物的果实、种子、块根的一部分，或采集来的果实、种子、块根的一部分，被带到临时的或半永久性的住所附近，之后，这些子实块根的一部分被遗留或有意地丢在这里，这种情况要持续很长的时间。
      3.只有最先适应的,高度变异的野生植物,能在住所附近占据被干扰过的土壤。人们从这些“杂草植物”中选取需用的植株的某些部分。
      4.不利的自然选择压力减少了，有利的选择压力被引进了，变异减少了，但因杂交和突变而增多的变异抵消了这种减少，继之以隔离，保护和选择，导致了来自野生表现型的更多的“变员”（deviants)能够存活。这种变员属于“穭生植物区系”（ruderal flora)，或“居住地杂草植物区系”（habitation weed flora)。这个阶段称之为“前农业”（proto-agriculture)时期。
      5.当需求超过了可能，人类对某些植物的依赖性更增加了，于是他就开始清除野生的杂草，或采取措施，以改进这些需求植物的生长。当人类的活动超出植物所能供应的范围，他就学会保留种子等办法。当植物生长在它原先生长的范围以外，人们就有目的地为植物翻动土壤，以便能更多地收获这些野生植物，这时，野草便变为一种作物了。这个阶段可称之为“初期农业”（incipient agriculture)。
      6.作物的进一步改进是通过半有意的和有意的改善农艺方法和植物类型，这个阶段可称为“有效的农业”（effective agriculture)。完全驯化的植物先要经过“部分驯化”的阶段，包括“穭生植物”（ruderal plants，是指野生于人类居住的环境中，不同于野生于自然界中，也不同于野生在栽培的田间）,

      “居住地杂草”（habitation weeds),和“垃圾堆植物”（rubbish heap plants)。凡是对人们有用的植物总是受到重视保护。
      最早的作物祖先必然具有杂草的特征，并且有很大的“食物”贮备，能抗干旱和耐贫瘠的土壤，没有多年生植物与它们竞争。在栽培条件下，通过反复的物种间、类型间、生态型间和种系间的分化及杂交周期而诱发变异。在分化的时期里，植物处于遗传的、种的、栽培的和杂交障碍的隔离状态之下。例如，杂交要受到从异花授粉向自花受粉转换的妨碍，受到开花期的改变或生态适应性改变的妨碍；有性繁殖的二倍体植物，其分化作用的时期要比无性繁殖的多倍体植物短得多。短的距离可以只有几百米，如斜坡上生长野生型，山谷地里生长栽培驯化植物。发生于驯化植物与杂草或野生亲缘间的杂交，常常导致一种“双向的基因流”（two-way gene flow)，当栽培的基因一显性时，它们就很少机会生存于杂草或野生植物中，如玉米和大刍草（maize-teosine)所表现的那样。杂草和野生亲缘的滋生，对于向日葵有很大影响，由于杂交，变异就会增多，适应性就会扩大；变异愈大，适应性愈广，该作物可以栽培的地方也愈广泛。
      驯化的速度取决于一个世代的长短，禾谷类的一个世代通常为一年，而无性繁殖的植物就不能期望有较快的改变。Braidwood及Howe (1962 )的估计，小麦和大麦的主要改变需要2000年以内，Helback (1966)的估计是1 500年。有些物种是因某种目的而被驯化的，
      Anderson (1960 )和Chang( 1970 )认为最早的栽培植物不是粮食作物，而是一些为了纹身、居住地筑栅栏、取毒、咀嚼、麻醉、宗教的目的而栽培。或者为了制作容器（竹筒、葫芦果实、）绳索、药草而栽培。这些植物都是原始人所需用的，一旦人们非依赖它们不可，人们就开始栽培它们。
      但是绝大多数的科学家相信最先驯化的是粮食作物。Burkill (1950 )列出他认为驯化作物的次序是：①禾谷类；②豆类；③绿肥；④油料种子；⑤块根类；⑥草本果实；⑦纤维；⑧木本果树；⑨各种工业用植物。
有些野生禾草植物非常适于驯化，因为它们能结大量的种子，它们成片成群的生长，很便于集体收获，它们的种子供食用，茎叶供饲料，种子又易贮藏，人类不会对此视而不见。不论这些学者的观点多么分歧，但他们对中国的看法则颇为一致，中国在他们的心中，都据有突出的地位，

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2.1.9 热带气温下降
V1 by angella0228 710
第三篇是关于热带气温下降的
说热带气温就下降了2度，别的地方都下降了5度。没人可以解释这个。一个科学家G做research发现海里一个什么动物的化石好像，表明他在***时候活着，而那个动物要在很高的温度才能生存，所以就觉得在***时候的气温就下降了2度。而陆地上证据表面下降的更多，和海洋不一致什么的，然后就cast doubt to 科学家G的结论。于是另一个科学家研究了一下发现那个人是错的，每个地方下降的温度都一样。
（1）    问G的research作用
（2）    另一个人的研究发现了什么

Scientists find world's biggest snake
'Titanic' boa fossils provide clues to past tropical climate.
Roberta Kwok
Researchers have found fossils of the biggest known snake in the world, a discovery that could shed light on the climate of the tropics in the past.
The scientists estimate the snake lived 58 to 60 million years ago and was around 13 metres long. The giant, found in northeastern Colombia, dwarfs modern pythons and anacondas which usually don't exceed 6-6.5 metres and are thought to be the largest living snakes.
Since snakes are poikilotherms that, unlike humans, need heat from their environment to power their metabolism, the researchers suggest that at the time the region would have had to be 30 to 34 degrees Celsius for the snake to have survived. Most large snakes alive today live in the South American and southeast Asian tropics, where the high temperatures allow them to grow to impressive sizes.
"We've taken the snake and turned it into a giant thermometer," says lead author and vertebrate palaeontologist Jason Head of the University of Toronto in Canada, who says he "just about screamed" when he first saw the size of the fossils.
“We've taken the snake and turned it into a giant thermometer.”
Jason Head
University of Toronto
Head's colleagues discovered fossilized vertebrae and ribs from 28 individual snakes in an open-pit coal mine at Cerrejón. The vertebrae's structure suggests the snake is closely related to the boa constrictor, leading the team to name the species Titanoboa cerrejonensis, or 'titanic boa from Cerrejon'. By comparing the shapes and sizes of the two best-preserved vertebrae to those of living snakes, the researchers calculated that the snake was 12.8 metres long and weighed 1,135 kilograms.
King of snakes
"It is hands-down the largest snake ever confirmed," says Harry Greene, an evolutionary biologist at Cornell University in Ithaca, New York, who was not involved in the work. "I think it's really spectacular."
Using models1 based on the largest modern-day snakes and their estimate of the Titanoboa 's size, the team calculated how hot the tropics must have been 58 to 60 million years ago, a period known as the Palaeocene. The mean annual temperature would need to be at least 30-34 degrees Celsius to support the snake's metabolism, the researchers report in Nature2. This range matches previous estimates from Palaeocene climate models that assume high atmospheric carbon dioxide concentrations3.
The results support the idea that the temperature difference between the Palaeocene tropics and higher-latitude regions was as large as it is today, even though the higher latitudes were much warmer during that time. This counters the so-called 'thermostat' hypothesis, which predicts that tropical temperatures would stay fairly stable even as other parts of the world heated up.
The study offers a "really big piece of evidence" to researchers trying to estimate Palaeocene climates, says Lisa Sloan, a climate scientist at the University of California, Santa Cruz. But Greene cautions that the team based their temperature calculations partially on the largest known size of an anaconda today, which the study pegs at 7 metres. This number is "very conservative" and could be as high as 11 metres, Greene says, which would lower the corresponding temperature estimate for the Palaeocene tropics.

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2.2.4伽利略
VI: michelleyiyan 再就是伽利略关于水能在pump里面通过多高的认识，后来说伽利略的认识是错误的，然后提出了另外一个人的观点。
阅读材料：感谢xibao大人！狗主人确定！
Galileo’s parti non quante seem to account for his curious physical treatment of vacua. His attention had been directed to failure of suction pumps and siphons for columns of water beyond a fixed height. He accounted for this by treating water as a material having its own limited tensile strength, on the analogy of rope or copper wire, which will break of its own weight if sufficiently long. The cohesion of matter seemed to him best explained by the existence of minute vacua. Not only did he fail to suggest the weight of air as an explanation of the siphon phenomena, but he rejected that explanation when it was clearly offered to him in a letter by G. B. Baliani. Yet Galileo was not only familiar with the weight of air; he had himself devised practicable methods for its determination, set forth in this same book, giving even the correction for the buoyancy of the air in which the weighing was conducted.
重要提示：http://www.encyclopedia.com/topic/Galileo.aspx这个是原地址, 介绍Galileo 生平. 然后大家search pump, 第一个pump的那一段就是了