动物科学专业考研方向有哪些

If you look for the most visited websites in the world,what you find is a list of sites owned by western corporalions,confirmation of the degree to which the web has been capturecl by the corporate world.1.The idea that a significant encyclopedia could be created by allowing anyone to create pages on any topic seemed pretty improbable way back in 2001 when it was introduced by Jimmy Wales.That it could have evolved into the world's leading general reference work-and the fifth most visited website on the planet-is truly extraordinary.Since its establishment,it's been the butt of jokes,a focus for academic anger.2.Indeed,in specialist areas,Wikipedia pages are often written by experts and are usually the best places to gain an informed and up-to-date overview.Because Wikipedia is so vast and varied,the controversies it engenders have traditionally been about its content and rarely about its governance,which is a pity,because in some ways this is the most significant aspect of the project.3.Wikipedia's governance is a clever mix of technology,norms and processes.It started with the wiki technology invented by Ward Cunningham,which allowed anyone to write and publish live web pages,together with an acceptance that while"truth"might be unattainable,nevertheless achieving what it called"a neutral point of vrew"was a worthwhile aspiration.4.From the beginning,Wikipedia had a core of volunteer editors who shared common values and some substantive expertise.And sitting atop this structure was a founder,Jimmy Wales,who operated as a kind of benevolent dictator and an arbiter of last resort.From a contemporary perspective,though,the most significant design decision was that every page would have a public discussion page attached to it,which meant that there would be a record of all the arguments that had led to particular changes.Reading Wikipedia discussion pages provides a way of understanding how a particular proposition or assertion came to be made and how it evolved over time.5.But in a polarised political climate,it shows what can be done to preserve us from the madness of hysterical,uncivil,conspiracist discourse that now characterises social media.Which,among other things,explains why Susan Wojcicki.YouTube's CEO,recently announced that the video site will henceforth use excerpts from Wikipedia to counteract videos romoting conspiracy theories.This,wrote one commentator,"is,at first glance,odd.A megacorporation with billions of dollars and thousands of brilliant employees is...relying on a volunteer-run platform anyone can edit to fact-check information?"It is odd.But it's also a validation of Wikipedia's mission and a reminder of its importance.
3选？

A.There were no gatekeepers-anyone could create a page on any subject-but the technology,which enabled rapid reversion to a pre-edited version,provided an effective antidote to vandalism.
B.The political events of the last two years should have alerted us to the fact that Wikipedia had to invent a way of tackling the problem that now confronts us at a global level:how to get at some approximation to the truih.
C.Mainiaining"the neutral point of view"is relatively easy when writing about science topics or otherwise objectively verifiable subjects.But in other topics,such as politics and hisiory,bias and controversy inevitably arise.
D.There is,however,one single ray of light in this depressing list.For there,in fifth place.is the antithesis to all of that:a site that embodies the potential of the internet to harness the collective intelligence of humanity-Wikipedia.
E.In June 2006,Roy Rosenzweig,a professor specializing in American history,stated that Wikipedia often fails to distinguish important from trivial details,and does not provide the best references.He also complained about Wikipedia's lack of"persuasive analysis and interpretations,and clear and engaging prose".
F.There was one moment when the vice-chancellor of a top university made a dismissive remark about Wikipedia,only to have a world-teading chemist in the audience icily retort that the pages on his speciality were the most up-to-date summary currently available anywhere-because he wrote them.
G.It's like reading the transcript of an argument that has gone on for a long time-an attempt to track rationality in action.Like every other human-made thing,it s imperfect.

基因表达调控的基本控制点是

A.基因结构活化
B.转录起始
C.转录后加工
D.蛋白质翻译及翻译后加工

下列选项中，关于承诺效力的表述，正确的是（　　）。
A.承诺在有效期内，受要约人可以撤回和撤销承诺
B.默示和不作为在特定情形下可以构成有效的承诺
C.要约人于收到迟到的承诺撤回通知时，及时通知承诺人承诺撤回通知迟到的事实，则发生撤回承诺的法律效力
D.承诺一经作出，并送达要约人，合同即告成立，要约人不得加以拒绝

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