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2020年02月27日 21:07:00 | 作者:365养生 | 来源:新华社
Science and technology科学技术New transistors新型晶体管Mechanical advantage机械优势Two new types of transistor may lead to simpler, more efficient computers两种新型晶体管或许会导致更加便捷高效计算机的出现WHEN baking a cake it helps to have all the ingredients within reach,当你在烧烤蛋糕的时候,它有会让所有的一切都变得触手可及,rather than wasting time and energy making frequent trips to the pantry.而不是让你在食品柜繁琐的开关之间浪费时间与精力。Something similar is true of the logic circuits in computersmicroprocessors.这也同样会真正应用于电脑微处理器中的某些逻辑电路。These could be made faster, and would consume less energy, if they were able to store information themselves instead of fetching it from separate memory chips or hard drives.如果这些微处理器自己能够储存一些信息,用来取代从原来相互独立的芯片或手工操作中获得的信息,它们的速度将会变得更快,能耗将会更低。The problem is that the transistors used to make logic circuits hold their electronic state, and therefore any data they contain, only when powered up.问题是,用来制造逻辑电路的晶体管中保留着它们的电子态,因此当这些晶体管通电的时候,它们会包含任何可能的数据。The choice engineers face is thus between supplying continuous power to a transistor, so that it can retain its memory,因此,工程师们面临的选择就是要么对晶体管提供一个持续的电源,让晶体管保持自己的记忆,and ferrying data that would otherwise be lost to and from so-called non-volatile memory devices that do not require continuous power.否则从所谓的非易失性半导体存储器中传输的数据就有可能丢失,不过它不需要持续的电源。Cracking this problem—so that transistors can act as their own non-volatile memory—would make all computers faster.解决这个问题——以便于让晶体管使用自身的非易失性半导体存储器—将会让所有的电脑运行速度更快。It would be particularly valuable, though, for mobile devices.虽然这对于移动设备来说,显得特别昂贵。These could be made smaller and lighter, since they would require fewer components.不过移动设备因此可以做得更小,更轻盈,因为它们需要的元件更小。And they could go for longer between charges.并且两次充电的时间间隔将会变得更长。To this end, Hiroshi Mizuta of the University of Southampton, in England, and Tsuyoshi Hasegawa of the National Institute for Material Science in Tsukuba, Japan, are proposing a marriage between two novel types of transistor that could hardly be more different.为此,英国南安普顿大学的Hiroshi Mizuta和日本筑波国立材料科学研究所的Tsuyoshi Hasegawa提出了将两种完全不同新型材料混合起来。One, the atomic transistor, draws on the latest advances in nanoscience.其中一种就是原子晶体管,它利用了最新的纳米科技。The other, the mechanical transistor, sounds as if it has been lifted from the annals of the industrial revolution.另外一种就是机械晶体管,这听起来就像是从工业革命史册中发掘出来的玩意儿。The atomic transistor works, as its name suggests, by shuffling individual atoms around within the device.原子晶体管的工作方式就像它名字所示的那样,是通过移动该元件内部的单个原子进行工作的。The atoms in question are copper, and the result of the shuffling is to create or destroy a conductive pathway between two crucial bits of the transistor, the source and the drain, thus switching the device on or off.这里所说的原子指的是铜原子,移动的结果主是在晶体管的两个十字位置构建或消除一个传导通路,它的源极和漏极因此就会开启或关闭。That is possible because this part of the transistor is made of tantalum pentoxide, a material whose atoms are arranged in a lattice which contains holes large enough for copper atoms to squeeze through.这是有可能实现的,因为这部分晶体管是由五氧化二钽制造的—这种材料可以将它自身的原子排布在晶格中,这些晶格包括一些足够大的孔,可以让铜原子挤过去。The mechanical transistor, more properly called a nano-electromechanical systems transistor, creates and destroys the connection between source and drain mechanically.机械晶体管,更确切地可以称之为纳米电子机械系统晶体管,它可以在源极和漏极之间机械地构建或消除连接。When a voltage is applied across two beamlike electrodes made of aluminium, which are separated by a gap of around 50 nanometres,两个柱状的铝电极间隔约50纳米,当电压加在这两个电极之间时,它们就会相互通电,charge builds up on each, creating an attractive force between them, until a critical point is reached.在二者之间会形成一股引力,直至达到一个临界点。At that moment one of the electrodes flips towards the other, causing the two to make contact.在达到临界点的那一刻,其中一个电极就会移向另一个电极,这两个电极就会形成通路。This closes the circuit and turns the transistor on. Apply the opposite charge and the electrode flips back, breaking the circuit.这样就会接通电路,打开晶体管。利用相反的电荷,电极就会复位,进而断开电路。What makes these two very different types of transistor attractive is that both the copper and the aluminium stay put when the power is turned off.这两种完全不同类型的晶体管如此吸引人的地方就在于断电后,如何让铜原子和铝电极待在原地。They can thus act as memories as well as processors.它们可以应用于储存芯片和处理器。The on state represents one type of binary digit and the off state represents the other.开的状态表示二进制中的一个数字,关的状态可以表示另一个数字。Dr Mizuta and Dr Hasegawa are therefore using the novel transistors to try to make the worlds first non-volatile processor chip.Mizuta士和Hasegawa士因此都在使用新型的晶体管,力图制造出世界上第一个非易失性处理器芯片。Ideally, such a chip would have only one sort of transistor, since that would mean it was much easier to manufacture.理想的这种芯片将只有一种晶体管类型,因为这意味着它将会更加容易制造。However, transistors come in two varieties, n-type and p-type.不过,晶体管却有两种,一种是N型,一种是P型。Both are needed in a logic circuit, but atomic devices can be only n-type.逻辑电路都需要这两种晶体管,不过在原子设备中,只需要N型。The alternatives, then, are to make the circuit entirely out of NEMS transistors,那么另一个方案就是完全用NEMS晶体管制造电路,or to mix the two by using atomic devices where an n-type transistor is needed and NEMS ones where a p-type is required.或者是将利用N型晶体管的原子设备和利用P型晶体管的NEMS晶体管混合起来。Dr Mizuta and Dr Hasegawa have opted for a mixture,士Mizuta和Hasegawa士选择了二者的混合,because atomic transistors are much smaller than NEMS ones, and the saving of space outweighs the awkwardness of mixing them together.因为原子晶体管比NEMS更加小巧,这样节省的空间就会消除二者的混合的尴尬。If their recipe works, it will mean far fewer electronic trips to the pantry and a quicker baking time for whatever answer the new chip is trying to cook up.如果他们的方案成功的话,这意味着食品柜中的开关将会大大减小,实现更短的烹饪时间。 /201305/239036Business商业报道Restructuring European aerospace欧洲航天重组Enders justifying means恩德斯的正当手段The effort to run EADS like an ordinary company努力像经营一个普通公司一样经营欧洲航空防务及航天公司ARNAUD MONTEBOURG must look back on September 16th with a certain wry amusement.阿诺·蒙特堡先生回顾9月16日时一定会哭笑不得。That was the day the French industry minister visited Elancourt, west ofParis, where the defence arm of European Aeronautic Defence amp; Space conducts research on cyber-security.这一天,法国工业部长参观巴黎西部的埃朗库尔酒店,那里是欧洲航空防务和航天公司进行网络安全的研究的防御区。The government had just publicly identified the sector as one that could propel Franceto a new industrial future, and Mr Montebourg waxed lyrical on site.政府刚刚公布确定这个部门作为一个可以推动法国新的产业未来的部门,蒙特堡先生。Then on December 9th EADS announced that it was cutting 5,800 jobs acrossEuropeas part of a reorganisation of its defence and space activities.12月9日EADS就宣布,它正在削减欧洲的5,800职位作为国防和空间活动的重组计划的一部分。In the past such an announcement would have set off a barrage of accusations, and not only from the firms workforce.在过去,这样的声明会掀起大批的指责,不仅仅是公司的员工。Relations among the companys main government shareholders—FranceandGermany—have long been strained.该公司的主要股东的政权,法国和德国,长期以来一直关系紧张。Those between Tom Enders, the chief executive of EADS, and Angela Merkel,Germanys chancellor, are no better.欧洲宇航防务集团的首席执行官托马斯·恩德斯和德国总理安格拉·默克尔之间的关系,也一直未见好转。It was Mrs Merkel who stopped a proposed merger last year between EADS and BAE Systems, a British defence firm.是默克尔终止了EADS和英国防务公司BAE系统公司在去年提出的合并计划。Mr Enders saw the deal as a way to win EADS a seat at the top table in the defence business.恩德斯先生将这一交易看做是EADS赢得国防业务顶尖席位的一条途径。Mrs Merkel thought it would reduce German influence over EADS and shift jobs out ofGermany.默克尔却认为这将减少德国对ESDS的影响力,EADS的许多工作将会被转移出德国。The merger was abandoned amid bitter recriminations, leaving Mr Enders determined to transform EADS into a normal commercial company focused on the profitability of its businesses rather than the nationality of its workers.这次放弃合使得双方都相互指责,恩德斯先生不得不下决心将EADS改造成为一个正常的商业公司,专注于各项业务的盈利能力,而非其工人的国籍。That the mudslinging this time has been relatively restrained is a sign of how far EADS has travelled down that road.这次较为克制的诽谤已经成为欧洲宇航防务集团在这条道路上走过多远的标志。The German economics ministry asked that the cuts do not bear down disproportionately on its country, where most of the defence operations are based.德国经济部指出这次削减难以承担德国经济不成比例的下跌,因为那里是大部分防卫作战的基础。Mr Montebourg thought it unacceptable that a profitable company with a bulging order book and state support had to cut jobs.蒙特堡先生认为一个拥有鼓鼓订单和政府持的盈利公司不得不裁员的理由是难以接受的。Neither government looks likely to intervene.Francenow owns just 12% of the company,Germanyless than 11% and neither now has a veto over management decisions.不过无论如何政府很可能要干预此事。法国目前只拥有公司的12%,德国也只有不到11%,两国都没有一票否决权的管理决策。Both can see that, however successful EADS is these days in commercial aviation, it is too small, too cost-heavy and too Eurocentric to compete globally for defence and space business, especially at a time when developed countries are cutting their budgets.从两方面都可以看出,虽然欧洲宇航防务集团最近在航空商业中是成功的,但对于以欧洲为中心在全球范围内为国防和空间业务构成竞争来说规模太小,花费太大了,尤其是当发达国家正在削减他们的预算的时候。The job losses are part of a bigger reorganisation to reflect this reality.工作损失是一个反映现实的更大的重组。Next year EADSs four operating units will come down to three, as its existing defence and space outfits—Cassidian, Astrium and Airbus Military—are merged into Airbus DS.明年欧洲宇航防务集团的四大经营单位将回落到三个,作为其现有的国防和航天装备,卡西迪安,奥斯特里姆公司和空中客车军用将合并成空中客车公司的DS 。EADS itself will take its name from its best-known brand, becoming Airbus Group.EADS公司将放弃其最知名的品牌名字,成为空中客车集团。No longer will the role of chief executive alternate between French and German bosses: Mr Enders will keep the job as long as the board wants him to remain.他们将不会再扮演法国行政总裁候补和德国老板之间的角色:What of the research into cyber-security that Mr Montebourg ventured out to see one September morning?只要董事会希望他留下来,恩德斯先生将继续这项工作。That, the company says, is here to stay.也就是说,该公司表示,是到停下来的时候了。 /201312/269450Science and technology科学技术Social networking for scientists为科学家务的社交网络Professor Facebook教授们的FacebookMore connective tissue may make academia more efficient更多连接持,涌动更有效率的学术界GIVEN journalists penchant for sticking the suffix gate onto anything they think smells of conspiracy,有鉴于记者们爱把见不得光的事件称为某某门。a public-relations consultant might have suggested a different name.有鉴于记者们爱把见不得光的事件称为某某门。But ResearchGate, a small firm based in Berlin, is immune to such trivia.如果研究之门公司雇佣公关顾问的话,它可能会被建议换个名字。It is ambitious, too—aiming to do for the academic world what Mark Zuckerberg did for the world in general, by creating a social network for scientists.不过这间柏林的小公司对这些琐事可没什么兴趣。它和Facebook 一样拥有雄伟壮志,旨在打造学术界的科学家社交网络,类似于马克·扎克伯格所建立的风靡大众的Facebook。And it is successful.现在它成功了。About 1.4m researchers have signed up aly, and that number is growing by 50,000 a month.大约有140万名研究人员已经注册了该网站,而且每个月还有五万名新增用户。Non-scientists might be surprised that such a network is needed.普通民众或许会对科学家如此需要此类网站而感到吃惊。After all, the internet was originally created mainly by academics for academics,毕竟,起初因特网是大学教师们为了大学教师而创立的,and Mr Zuckerbergs invention, Facebook, got its start on college campuses.马克·扎克伯格的Facebook起步也是在大学校园。But though the internet has speeded things up, it has not fundamentally changed how researchers are connected.纵然因特网提高了信息的流通速度,但它却没从根本上改变研究人员的联系方式。Academic communities are still pretty fragmented, frequently making it hard for scientists to find others doing similar research.学术界仍是非常碎片化,因此科学家们常常很难找到和自己做着类似研究的人。And results often are not shared across disciplines.而且通常,他们的实验结果都不能实现跨学科的交流。To make things more efficient and interdisciplinary, ResearchGate wants to help the academic world to grow more connective tissue, as Ijad Madisch, one of the firms founders, puts it.研究之门公司的创始人之一,伊贾德·马迪士表示,为了让科学研究变得更富有成效以及跨学科性,研究之门意欲促使学术界像结缔组织那样更具有持连接功能。As on Facebook, users create a profile page with biographical information, list their interests and research skills, and join groups.像在Facebook网站那样,用户在研究之门网站上可以创立一个个人信息页,在上面填写传记性的信息,罗列他们的兴趣,研究技能以及所加入的小组。They can see what others with similar interests are up to and post comments.用户可以查看那些和他们有着相似兴趣的人最近的计划,以及在对方的个人页面发表。They can also upload their papers and create invitation-only workgroups.用户还可以上传自己的论文,和创立需要申请才能加入的工作小组。The big question is whether ResearchGate will make enough money to keep its investors happy.现在最大的问题是,研究之门能否赚取足够的利润以满足它的投资者。So far, it is running on cash from Accel Partners and Benchmark Capital, two venture capitalists based in Silicon Valley.迄今为止,它的资本来源于加速合伙公司和基准资本这两家硅谷的风险投资公司。A third firm is expected to join them soon.不久之后,预计会有第三家公司加入投资。But these people will want a return on their investment.不管怎样,这些投资者都想要投资回报。Some of that may aly have come from the Max Planck Society,部分已有盈利可能来自于克思·普朗克学会。which runs many of Germanys best research campuses and had ResearchGate build it a private network.这个学会掌控着德国大部分最好的研究型大学资源,同时,它也让研究之门为自己创建了一个私人网络。Over the longer haul, the firm hopes to charge companies and universities for using it to advertise jobs, and to operate a marketplace for laboratory materials.经过比较久的艰苦经营,研究之门希望能跟那些利用其网站平台刊登职位供求广告的公司或大学征收费用。It has no plans to post other advertising, though, nor to charge its users directly.与此同时,研究之门计划建立一个实验室器材的市场。公司并没有计划向用户发布其他广告,而且也不计划向用户直接收取费用。At the moment, most of those users are in their 20s.目前,网站的大多数用户是20几岁的年轻人。Their favourite activity is to ask each other questions about practical research problems, from DNA-sequencing techniques to statistical tricks.他们最喜欢做的事就是向彼此询问一些有实用价值的研究问题,从DNA测序技术到统计戏法之类。They are also busy ing each others papers: more than 10m have been uploaded.他们同样忙于阅读彼此的论文:有超过1000万的论文上载到研究之门。The service certainly saves these young researchers trial and error, and therefore time and money.很显然,这项务减少了这些年轻的研究者犯错误以及做无效实验的次数,从而也节省了他们的时间与金钱。They will probably also like a new feature ResearchGate is planning to introduce in April:他们很有可能会喜欢研究之门计划于四月份推出的新功能:a feedback system which lets users rate each others contributions. This would allow them to build a reputation other than by publishing papers.让用户们互评贡献的反馈系统。这个功能可以让用户找到除了发表论文之外,另一种可以建立自己声誉的渠道。Scientists whose reputations are established may be more hesitant, though,那些享有声誉的科学们也许会变得更犹豫不决。and not just because they are set in their ways.然而这并不仅仅是因为他们有自己一套坚定的准则。Science is not only about collaboration but also about competition.科学并不只有合作,更充满竞争。This limits what people are willing to share.这就限制了人们愿意分享的东西范围。But Dr Madisch is optimistic.但是迪福士士对此持乐观态度。Those who have grown up with Facebook, he says, know that sharing will improve their research.他说,那些伴随着Facebook成长的一代,意识到分享会对他们的研究有所提高。And their older colleagues will eventually come around—or retire.而比他们年长的那些同事会重归此道,抑或退休。 点击此处下载本期经济学人讲解PDF与音频字幕 /201306/245670

How many times have you heard a jet plane going over, looked up to see it, but not been able tofind it even though you were looking toward where the sound was coming from?有多少次你听到一架喷气式飞机飞过,抬起头去看它,即使你朝着声音传来的地方望去,却仍然无法找到它?Well, thismoment of science is going to tell you why you couldnt find it?那么这次科学时刻将会告诉你为什么你找不到它。Sometime during your life you might have been told that the plane wasnt with the sound becauseit was traveling faster than the speed of sound.在你生活中的某个时候,你可能被告知看到的飞机和听到的声音是不在同时出现的,这是因为光的传播速度比声音快。It might have been, but it didnt have to be goingthat fast in order to appear to be separated from the sound.它可能是这样的,但它没有必要为了同声音分离而飞的那么快。The reason the jet appeared to be apart from the noise it was making was simply that soundtravels a lot more slowly than light-about a million times more slowly.喷气式飞机之所以和它产生的噪音相分离,是因为声音传播速度比光速慢一百万倍。For quick review, at sea levelsound travels about seven-hundred-fifty miles per hour, light travels at 186,000 miles per second.简单回顾一下,在海平面上,声音的传播速度大约是每小时750英里,而光速则是每秒186,000英里。Commercial jets normally fly at about thirty-thousand feet.商用喷气式飞机一般在30,000英尺的高空飞行。From that height it takes sound aboutthirty seconds to reach earth.从那个高度,声音传送到地面需要30秒的时间,Light gets here in only about four one-hundred-thousandths of asecond, or for practical purposes, instantaneously.而光到达地面仅仅需要4/100,000秒,实际上就是瞬间到达。A plane travelling at six-hundred miles an hour goes five miles in the thirty seconds it takes for thesound to reach you.一架每小时飞行600英里的飞机在30秒中飞行了5英里,而声音传到你所在的地方需要30秒。By the time the sound from the plane reaches your ears, the plane is fivemiles from where that sound originated.在这30秒的时间里,声音从飞机传到你的耳朵里,而飞机离声音发出的地方已经有了5英里的距离。So, when you look toward the sound, the plane is notthere anymore.所以,当你朝声音发出的地方望去的时候,飞机早已不在那里了。 201405/294731

Coal煤炭The fuel of the future, unfortunately很不幸,这便是未来的能源A cheap, ubiquitous and flexible fuel, with just one problem这是一种廉价、易得且用途广泛的燃料,但仅存在着一个问题WHAT more could one want? It is cheap and simple to extract, ship and burn. It is abundant: proven reserves amount to 109 years of current consumption, reckons BP, a British energy giant. They are mostly in politically stable places. There is a wide choice of dependable sellers, such as BHP Billiton (Anglo-Australian), Glencore (Anglo-Swiss), Peabody Energy and Arch Coal.还能奢望更多的好条件吗?这是一种廉价,且便于获取、装运和燃烧的能源。它的储量十分丰富:英国能源巨头BP实,现有的煤炭储量可供人们维持目前的消耗量长达109年。煤炭资源还大多分布于政治稳定的地区。可靠的煤炭供应商数量众多,如必和必拓、嘉能可,以及皮迪和阿齐。Other fuels are beset by state interference and cartels, but in this industry consumers—in heating, power generation and metallurgy—are firmly in charge, keeping prices low. Just as this wonder-fuel once powered the industrial revolution, it now offers the best chance for poor countries wanting to get rich.其他能源均被国家或者卡特尔寡头所控制,但在煤炭产业当中,其供暖、电力和冶金业的消费者处于绝对主导地位,令价格持续低廉。正如当年这一完美的能源推动着工业革命的发展,现在它也为贫穷国家们提供着发家致富的绝佳机会。Such arguments are the basis of a new PR campaign launched by Peabody, the worlds largest private coal company. And coal would indeed be a boon, were it not for one small problem: it is devastatingly dirty. Mining, transport, storage and burning are fraught with mess, as well as danger. Deep mines put workers in intolerably filthy and dangerous conditions. But opencast mining, now the source of much of the worlds coal, rips away topsoil and gobbles water. Transporting coal brings a host of environmental problems.如此的论断正是皮迪公司发起的新一轮公关活动的核心内容,而目前该公司是全世界最大的私人煤炭企业。煤炭本该成为上帝的惠泽,而若不是因为这一个小小的问题:它的破坏性污染。开采、运输、储存和燃烧使用的一系列过程中,不仅充满着问题,还具有相当的危险性。深入地下的矿井意味着矿工们要在难以忍受的肮脏以及危险的条件下工作。但目前大多数煤矿所进行的地表开采,不仅会使地表土壤流失,同时也消耗着大量的水。煤炭的运输还会带来一系列的环境问题。The increased emissions of carbon dioxide from soaring coal consumption threaten to fry the planet, as the Intergovernmental Panel on Climate Change reminded everyone in a new report this week. The CO2 makes the oceans acid; burning coal also produces sulphur dioxide, which makes buildings crumble and lungs sting, and other toxic chemicals. By some counts, coal-fired power stations emit more radioactivity than nuclear ones. They release tiny, lethal particulates. Per unit generated, coal-fired stations cause far more deaths than nuclear ones, and more even than oil-fired ones.正如联合国政府间气候变化专门委员会在这周最新的报告中所提醒的,持续增长煤炭消耗带来的二氧化碳排放的增加,使得地球温室效应加剧。二氧化碳的增加使得海水的酸度增加;与此同时,煤炭的燃烧产生二氧化硫和其他一些有毒化学物质,而这导致了建筑物结构的损伤以及人类肺部的损害。根据某种计算方式,煤炭发电厂所排放的辐射物质甚至比核电厂所排放的还要多。各大电厂所排放的都是极小的致命微粒。而煤电厂每单位发电排放的致命微粒要远比核电厂多,甚至比石油发电厂还要多。But poverty kills people too, and slow growth can cost politicians their jobs. Two decades of environmental worries are proving only a marginal constraint on the global coal industry. Some are trying to get out: in America Consol Energy is selling five mines in West Virginia to concentrate on shale gas. Big coal-burners such as American Electric Power and Duke Energy are shutting coal-fired plants. Yet despite Americas shale-gas boom, the federal Energy Information Administration reckons that by 2040 the country will still be generating 22% of its electricity from coal. The International Energy Agency has even predicted that, barring policy changes, coal may rival oil in importance by 2017. As countries get richer they tend to look for alternatives—China is scrambling to curb its rising consumption. But others, such as India and Africa, are set to take up the slack.但贫穷问题也同样危害着人们的生命安全,而缓慢的经济增长更是会令政治家们失去自己的饭碗。二十年来的环境问题,实了目前对于全球煤炭行业仅仅存在着一个最基本的限制。部分煤炭企业则试图抽身离开:美国康寿能源公司正在叫卖位于维吉尼亚西部的五个煤矿,从而专注于页岩气的开发。像美国电力和杜克能源等大型煤炭消耗的电力公司,则着手关闭他们旗下的煤电厂。但尽管美国页岩气开采实现了产量增长的井喷,联邦能源信息预计截至2040年全国发电量中的22%会来自煤电厂。国际能源总署甚至还预言说,除非政策发生变化,煤炭的地位很可能在2017年便超越石油。随着国家的富强,宏观管理当局总倾向于在能源方面寻找煤炭的替代品---中国目前正积极削减节节攀升的煤炭消耗。但像印度和非洲地区的其他国家,正准备填补煤炭需求的短缺。Americas gas boom has prompted its coal miners to seek new export markets, sending prices plunging on world markets. So long as consumers do not pay for coals horrible side-effects, that makes it irresistibly cheap. In Germany power from coal now costs half the price of watts from a gas-fired power station. It is a paradox that coal is booming in a country that in other respects is the greenest in Europe. Its production of power from cheap, dirty brown coal (lignite) is now at 162 billion kilowatt hours, the highest since the days of the decrepit East Germany.美国天然气市场的繁荣,促使着本地煤炭企业到海外拓展市场,推动者煤炭国际价格的下跌。只要一天消费者们仍不用对燃烧煤炭的副作用承担责任,那么煤炭价格将依旧保持那让人难以拒绝的低廉。在德国,煤炭发电的成本仅为天然气发电的一半。这是一个多么自相矛盾的情况:煤炭正推动着其经济的发展,而在其他方面,德国却是欧洲最环保的国家。由廉价、肮脏的棕色煤块(褐煤)所产生的电力,目前已经达到了自东德时期以来的最高水平,达到了1620亿千瓦时。Japan, too, is turning to coal in the wake of the Fukushima nuclear disaster. On April 11th the government approved a new energy plan entrenching its role as a long-term electricity source.随着福岛核电站事故的发生,日本也转向于使用煤炭发电。在4月11号,日本政府颁布了新的能源规划,以巩固煤炭作为长期发电燃料的地位。International coal companies face two worries. One is that governments may eventually impose punitive levies, tariffs and restrictions on their mucky product. The other is the global glut. Prices for thermal coal are at 80-85 a tonne, which barely covers the cost of capital. Some Australian producers are even mining at a loss, having signed freight contracts with railways and ports that make them pay for capacity whether they use it or not.国际煤炭公司面临着两大问题。首先是各大政府或许最终会对他们肮脏的产品征收惩罚性的税费、增加关税以及增设限制。其次,便是全球煤炭市场的供过于求。电煤的价格位于每公吨80至85美元之间,而这仅仅只够补偿资金成本。由于签订了铁路和港口的运输合同,部分澳洲供应商甚至还处于亏损的经营状态。One answer to that is cost-cutting and efficiency, much stressed by companies such as BHP Billiton. Unlike oil and gas, coal is geologically simple and does not require a costly array of drills, platforms and pipes. If the price is too low, companies can decide to stop production and await better times. But thriftiness with capital has its limits: the cost of mining is going up, as the easiest coal seams are worked out.其中一个解决之道,在于成本削减和效率提升,而一些公司已大力着手实施,例如必和必拓。与油气资源不同,煤炭开采的地理复杂程度低,不需要成本高昂的钻井平台和输送管道。如果价格太低,公司可以选择停止开采以等待更好的机会。但缩减投资规模也有它的局限:在最便利的煤层开采完毕后,接下来的煤炭开采成本便会持续上升。Some companies have tried to switch efforts to “met” coal, which fuels smelters. This was thought to be scarcer and more profitable. But that theory has suffered. Supplies of met coal have proved more abundant than expected.一些公司已经尝试去开发冶金煤炭市场。冶金煤炭,是专为熔炉供热使用的煤炭,而这部分的资源曾被人认为是较为稀缺且利润丰厚。然而,这一想法显然与事实不同。冶金煤炭的供应已经被实了远比设想的要充足。Perhaps the biggest hope for all involved in the coal industry is technology. Mining and transporting coal will always be messy, but this could be overlooked were it burned cheaply and cleanly. Promising technologies abound: pulverising coal, extracting gas from it, scrubbing emissions and capturing the CO2. But none of these seems scalable in the way needed to dent the colossal damage done by coal. And all require large subsidies—from consumers, shareholders or taxpayers.也许对所有煤炭行业相关的人来说,最大的希望是在于科技的发展。虽然煤炭开采和运输问题将一直存在,然而,如果它的燃烧利用能变得更为干净和低廉,上述小问题肯定会被大家所忽略。大量的技术值得我们去期待:煤炭粉碎、煤块提取燃气、气体排放净化以及二氧化碳捕获。但对于减少由煤炭造成的巨大伤害方面,这些技术都没有所需要的促进作用。与此同时,这些技术的开发还需要来自消费者、企业股东以及纳税人的巨额资助。A 5.2 billion taxpayer-supported clean-coal plant in Mississippi incorporates all the latest technology. But at 6,800 per kilowatt, it will be the costliest power plant yet built. At those prices, coal is going to stay dirty.在密西西比州,一座由政府出资价值52亿美元的清洁煤炭发电厂,集中了所有最新科技。但那儿每千瓦时的发电成本高达6800美元,创下了有史以来的电厂发电最高的成本。如此高价的清洁代价,意味着煤炭目前还得贴着污染的标签。 /201404/289948

Science and technology科学技术Cancer and the microbiome癌症和微生物组A punch in the gut肠道里的元凶How microbes promote liver cancer in the overweight微生物如何诱发胖人的肝癌OBESITY brings problems—notably heart disease, diabetes and cancer.肥胖产生了问题―尤其是心脏病、糖尿病和癌症。It is not hard to understand its connection with heart disease and diabetes: excess fat clogs arteries and messes around with the metabolism.肥胖与心脏病、肥胖与糖尿病的联系不难理解:多余脂肪堵塞血管,使新陈代谢紊乱。Its link with cancer is less intuitive.但是肥胖与癌症的联系凭直觉就不能理解了。Shin Yoshimoto of the Japanese Foundation for Cancer Research, in Tokyo, and his colleagues suspect this is at least partly because researchers have been looking for that link in the wrong place.位于东京的日本癌症研究基金会的Shin Yoshimoto以及他的同事怀疑,这主要是因为研究人员的研究角度错误。Most work in the field is focused on the cells of the human body.此领域的多数工作只是集中在人身细胞的研究。But researchers should, Dr Yoshimoto believes, be at least as interested in the cells of the microbiome, the collection of 100 trillion bacteria that live in the gut.Shin Yoshimoto认为,研究人员应当留心微生物组,这群生活在肠道的100万亿个细菌群。Mostly, the microbiome is beneficial.微生物组中的大多数都是有益的。It helps with digestion and enables people to extract a lot more calories from their food than would otherwise be possible.它们帮助消化,让人体从食物中分离出更多的能量。Research over the past few years, however, has implicated it in diseases from atherosclerosis to asthma to autism.然而,近几年的研究工作认为,微生物组是造成动脉硬化或孤独症等的病因。Dr Yoshimoto and his colleagues would like to add liver cancer to that list.但是,Yoshimoto以及他的同事则认为微生物组也是肝癌的病因。Their paper making this accusation is published in this weeksNature, and it is a careful, step-by-step analysis of the matter.他们的论文指出指控,发表在本周的《自然》杂志上。本篇文章进行了仔细、逐步的分析。They start from the facts that fat animals have different gut bacteria from thin ones; that some bacteria produce inflammatory molecules as part of their metabolism; and that inflammation promotes cancer.文章开始便列举了事实,肥胖动物的肠道细菌与瘦的不同;某些细菌在新陈代谢过程中产生一种能引起炎症的分子;炎症诱发癌症。They began their experiments by feeding laboratory mice a fatty diet, to make them obese.他们通过实验小鼠进行实验,喂养高脂肪食物,让它们长胖。Such mice, they found, are no more likely to develop cancer than those fed an abstemious diet.他们发现,吃了脂肪含量高的小鼠患癌症的机率不高于饮食有度的小鼠。Obesity alone, then, does not seem to cause tumours. But it might still promote them.因此,单独肥胖一项因素不会引起肿瘤,但是仍然会诱发肿瘤。Their next experiment therefore started by giving the mice a carcinogen known to trigger tumour formation throughout the body.因此,他们下一步的实验就是喂养小鼠能在全身形成肿瘤的致癌物质。One group was then fed standard fare while another got the high-fat diet.一组实验小鼠喂养标准食物,另一组喂养高脂肪食物。After 30 weeks, just 5% of the slim group had developed tumours, not in the liver but in the lungs.30个星期后,体形瘦削的那组只有5%患有肿瘤,不是在肝脏,而是在肺部。In the obese group, every animal had developed liver cancer.体形肥胖的那组,每只小鼠都患上了肝癌。To understand how this happened, the researchers began with the tumours and worked backwards.要了解其中的原因,研究人员先从肿瘤入手,采用了反正法。First, they found that the cancerous liver cells in their mice were generally accompanied by cells that had the symptoms of old age.首先,他们发现,实验小鼠中癌化的肝脏细胞周围的细胞出现了老龄化的症状。Such cells also emit chemical signals which promote inflammation, and thus encourage tumours.这些老化细胞会释放出引发炎症的化学信号,并进一步诱发肿瘤。The researchers suspected that these cells were being made senescent by something produced by gut bacteria.研究人员怀疑,细胞出现老化是由肠道细菌产生的某些物质所致。That suspicion was confirmed when they served some of their mice a cocktail of four antibiotics, to prune the animals microbiomes.研究人员混合了四种抗生素,喂养小鼠时,减少小鼠体内的微生物群。This treatment lowered the number of senescent and cancerous cells, suggesting the microbes were indeed to blame for promoting cancer.此时,他们的怀疑得到了实。这种喂养方法减少了老化和癌化细胞的数量,表明微生物确实是诱发癌症的因素。Dr Yoshimoto and his team then started to focus on which bacteria were causing the problem.接下来,Yoshimoto和他和团队开始研究是何种微生物导致问题。First, they discovered they could get the same cancer-suppressing effect using just vancomycin, an antibiotic that kills only “Gram-positive” bacteria.首先,他们发现,用专杀“革兰氏阳性”细菌的抗生素万古霉素进行实验,也能取得相同的抑癌效果。They also observed, as prior research had suggested, that a fatty diet raised levels of a chemical called deoxycholic acid and that antibiotics lowered it.同时,他们发现,高脂肪饮食会提升化学物质脱氧胆酸的水平,万古霉素会使其降低。Previous research had demonstrated too that DCA damages DNA in a way that promotes senescence.先前的研究也发现,DCA会以一种诱发衰老的方式破坏DNA。Dr Yoshimoto showed that lowering DCA levels in mice did indeed reduce the development of liver cancer.Yoshimoto让人们看到,降低实验小鼠体内DCA的水平确实会减少诱发肝癌的机率。Certain types of gut bacteria, including strains of Clostridium, are known to burp out DCA.某些肠道细菌,包括梭状芽胞杆菌菌株,研究人员进行进一步的工作,包括研究小鼠粪便。And further detective work, including examination of the mices faeces, revealed higher levels of a strain of Clostridium called OUT-1105 in the fat mice than in the thin ones.他们研究发现,肥胖的小鼠粪便中OUT-1105这种梭状芽胞杆菌的水平要高于瘦削小鼠。This strain, Dr Yoshimoto thinks, is the most likely culprit.Yoshimoto认为,这种梭菌很有可能就是罪魁祸首。There is, then, a chain of causation leading from the gut to the liver that promotes tumours in obese mice.之后,他们又发现了一连串的因果现象,说明了肥胖小鼠体内从大肠到肝脏诱发肿瘤的成因。And the chances are good that something similar pertains in Homo sapiens.这提供了好机会,因为这个过程与人体内的过程相似,Humans are not mice, of course.虽然人不是老鼠,But the two species microbiomes often do behave in the same way.但两者的运行机制还是相似的。If cancer does end up being added to the growing list of problems which an upset microbiome can cause, that may stimulate research into ways of tweaking it to stop it causing disease.人体内的微生物组令人烦恼,因为它会导致一些问题,而且由它导致的问题还在不断增加。假如由它导致的癌症防止不了,那么这就会刺激研究对微生物组进行调整,地防止产生疾病。It will also, once again, emphasise the microbiomes role, for both good and ill, as an adjunct part of the human body在此需要再一次地强调微生物组的作用,不论好与坏,毕竟它们都是人体的附属部分 /201311/263730

Finance and economics财经商业The new head of the Federal Reserve新任联邦储备局长Dove ascendant鸽派主政Janet Yellen will stick to her predecessors expansionary policies詹尼特将会继续推行前任扩张性经济政策FOR most of the past few years, monetary policy has urged the economy on while dysfunctional fiscal policy has held it back.过去的几年货币政策促进了美国经济的发展而运行不正常的财政政策却阻止其发展。Barack Obamas decision to nominate Janet Yellen to succeed Ben Bernanke as the Feds chairman in February raises the odds that stimulative monetary policy will continue.巴拉克·奥巴马提名Janet Yellen 接过Ben Bernanke的衣钵于二月担任联邦储备局主席一职,这将加大继续推行刺激性的货币政策的优势。But disquiet about that stance is growing.然而人们对于这一立场的担忧不断增长。In addition to being the first woman to run the Fed, Ms Yellen is also the first acknowledged dove.她不仅是首位入主联邦储备局的女性,而且是著名的鸽派人物。Presidents once felt compelled to appoint monetary-policy hawks such as Paul Volcker and Alan Greenspan to reassure markets that the Fed would not succumb to the political systems inflationary bias.总统为情况所迫曾任命鹰派强硬持货币政策的Paul Volcker和Alan Greenspan确保市场运行良好,避免联邦储备局遭受来自政治体系的通货膨胀趋势。In appointing Ms Yellen Mr Obama has implicitly acknowledged how much the world, and the Feds priorities, have changed.通过任命Ms Yellen,奥巴马含蓄地表明世界的转变,联邦储备局重心的转变。Since 2008 America, like many other countries, has struggled with slack demand and high unemployment.如许多其他国家一样,自2008年以来,美国一直为疲软的需求及较高的失业率所困扰。Meanwhile, energy prices excluded, inflation has persistently fallen short of the Feds 2% target.与此同时,排除能源价格的影响,通货膨胀率一直未能达到联邦储备局2%的目标。Ms Yellen is not alone in believing that unemployment is a bigger problem than inflation.并非Ms Yellen一人认为较之通货膨胀失业率居高不下是更为严重的问题,So do most of her colleagues on the Federal Open Market Committee, through which the Fed sets interest rates.她很多在联邦公开市场政策委员会制定联邦利率的同事也这么认为。But she has felt that way longer and more strongly.但她比他们更早更强烈地意识到这一点。She pushed publicly last year to hold interest rates near zero for longer than the Fed then planned, to hasten the fall in unemployment, even if that caused inflation to rise briefly above 2%.去年她公开推进利率趋零以促进就业降低失业率,使这一货币政策比联邦计划的时间要长,即便这一行动使通胀率高于2%。She was the principal author of the Feds current statement of long-term goals and operating principles, which stresses the equal importance of its twin statutory goals of full employment and low inflation.她是此次联邦现行长远目标及管理原则的主要推行者,这一政策将促进就业和压低通胀率这两个法定目标置于同等重要的地位。As vice-chairman, Ms Yellen helped Mr Bernanke nudge the FOMC towards its commitments to keep its benchmark interest rate at zero at least until unemployment has dropped to 6.5% and to keep buying billion-worth of bonds a month with newly printed money until the labour market has improved substantially.过去作为联邦储备局副主席,Ms Yellen协助Mr Bernanke推进联邦公开市场政策委员会实践其承诺,保持基准利率为零的状态直至失业率至少降至6.5%,继续印刷新钱购买850亿美元的债券直至劳动力市场情况持续好转。These policies have not fuelled inflation, as hawks feared they might.这些政策并没有像鹰派预估的那样加速通胀。Indeed, Ms Yellen would probably welcome having to tighten due to inflationary pressure, because that would mean demand was buoyant.的确,要是通胀压力过大,Ms Yellen势必会实施紧缩的货币政策,因为这意味着市场需求旺盛。But hawks still worry that the Fed is distorting prices in financial markets, breeding excessive risk-taking and preventing investors in Treasury bonds from demanding fiscal discipline.然而鹰派依然担心联邦储备局打乱了金融市场的价格,导致过多的风险从而使投资者因为繁多的财政纪律放弃购买国库券。Such concerns are widesp among Republicans in the Senate.参议院的共和党人普遍担心这一趋势。Several voted against her nomination to be vice-chairman in 2010.2010年几个议员在提名她为联邦储备局副主席时投了反对票。She was not particularly modest about the role of monetary policy in the economy and I dont see any evidence that thats changed, one such Republican, Bob Corker ofTennessee, said this week.一位来自田纳西州的共和党议员Bob Corker本周称,对于货币政策在经济中所扮演的角色,Yellen似乎不是很审慎,并且我并没有看到她作出的改变。With the support of the Senates Democratic majority, Ms Yellen is almost certain to be confirmed.因为得到参议院大多数民主党议员的持,Ms Yellen在联邦储备局的地位已经确立。But with many Republicans opposed, she will probably get fewer than the 70 votes Mr Bernanke did for his second term in 2010, at the time the lowest on record for a Fed chairman.但由于许多共和党人反对,她的得票很可能会比Bernanke2010年连任时的70票更低,而这在当时创造了联邦储备局主席最低的得票率记录。Moreover, one of the seven seats on the Feds board is vacant and another five may come up for grabs in the coming year, given expirations and the tug of other opportunities.此外,联邦董事会7个席位尚有一个空缺,在下一年换届时,倘若还有其他有利机会将有5人竞争该席位。The weight of opinion within the institution could change markedly as a result.因此,联邦储备局内部观点很可能会带来巨大转变。Minutes of the Feds last meeting, in September, show that it is aly divided on QE.联邦储备局9月份的会议记录显示,人们对量化宽松的货币政策已有分歧。Many officials wanted to slow its pace.很多官员想要放缓量化宽松的步伐。But the view that the economy was not strong enough prevailed, and the Fed surprised the market by sticking to its current pace of bond-buying.然而经济状况并不允许紧缩货币政策的观点盛行,联邦继续推行现行券交易的步伐出乎市场的预测。Once in office, Ms Yellen is likely to pursue a gentle taper coupled with a firm commitment to keep interest rates at zero.一旦就任,Yellen很可能会追求趋缓温和的货币政策但是会坚持维持利率为零。If the economy falters—an all-too-real possibility givenAmericas budget mess—she may want to increase QE, but might struggle to persuade her colleagues.倘若经济衰退—美国混乱的经济预算负主要责任—她可能会提高量化宽松的程度,但她要费力地说她的同事们持她。The Feds strength, she said in accepting the nomination, is its capacity to vigorously debate diverse views, and then to unite.在接受任命的时候,她说联邦储备局的优势在于它能够让不同的观点相互辩论最后获得统一。Maintaining that trait may be her biggest challenge.而发扬这种优良传统或许是她面临的最大挑战。 /201310/260172

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