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2019年10月24日 00:42:32来源:百度口碑

Science and technology科学技术Human evolution人类的进化Ask the family寻根问祖Human ancestry has just got more complicated人类祖先之谜变得愈加复杂了ONE of the oddest things about Homo sapiens is that he is alone.有关智人的最奇怪的事情之一就是他们在人类的进化史上十分孤独。Though storytellers have filled the world with imaginary hominids—from woodland pixies to mountain giants—no sign of the real thing has ever been seen.尽管故事家们想象出了许多人种来丰富这个世界,从森林里的小精灵到山上的巨人等等,但人们却从未找到能明这些人种真实存在的迹象。But that was not true in the past.但从过去来看,这样的说法并不正确。As recently as 40,000 years ago there were three other species of human on Earth: Neanderthals in Europe, the hobbits of Flores, in Indonesia, and a recently discovered and still mysterious group of creatures called the Denisovans, who lived in Central Asia.早在4万年前,地球上还存在另外三个人种:欧洲的尼安德塔人,印度尼西亚佛洛里斯岛上的霍比特人,以及最近才发现的一个叫丹尼索瓦人的神秘人种,该人种曾居住在亚洲中部。And now there is evidence that similar diversity existed earlier in human history, a little under 2m years ago, in Africa.而现在,人们在非洲又找到了另一个人种存在的据,该人种在人类进化史上出现的时间更早,距今约不到200万年。This evidence, just published in Nature, has been provided by a team led by Meave Leakey of the Turkana Basin Institute in Nairobi, Kenya.这些发表在《自然》杂志上的据是由肯尼亚首都内罗毕的图尔卡纳盆地研究所的一个研究小组提供的。Dr Leakey is a member of an illustrious palaeontological clan.该研究小组的领导人米芙利基来自一个著名的古生物学研究家族,Her husband, Richard, discovered in 1967 that the area around Lake Turkana is a good place to look for human fossils and made many important finds there; Richards parents, Louis and Mary, had earlier been responsible for showing the same was true of Olduvai Gorge in Tanzania; and in 1999 Dr Leakey herself found a new species of hominid, called Kenyanthropus platyops.1967年,她的丈夫理查德发现图尔卡纳湖附近区域是一块寻找人类化石的好地方,并在那里取得了许多重要发现。理查德的父母路易斯和玛丽曾在早些时候负责坦桑尼亚奥杜瓦伊峡谷的人类化石发掘工作。米芙?利基士本人曾在1999年发现了一个叫肯尼亚平脸人的新人种,At 3.5m years old Kenyanthropus predates Homo, the genus to which modern humans belong. Her latest discoveries, however, add to that genus, too.该人种距今已有350万年,其出现时间比现代人所属的智人还早。而她最新取得的发现成果又给这一人种增添了新成员。The problem with studying humanitys fossil record is that it is so sparse: a jawbone here; a braincase there.研究人类化石记录最大的问题是资源稀缺,Often, it is difficult to know if different bones have come from the same species or not.总是这儿一块颚骨,那儿一块头骨。Even multiple examples of the same type of bone can mislead.而且研究者通常很难分辨它们是否来自同一人种。What looks like two species might actually be the male and the female of one.即便是同一人种,不同样本也会给人带来误导,两块看起来像是来自不同人种的骨头实际上可能分属于同一人种的男性和女性。Such confusion has bedevilled the interpretation of the human fossils found near Lake Turkana.这种极易混淆的情况一直困扰着那些想要解读图尔卡纳湖附近人类化石的研究者们。Some palaeontologists see a single, variable species called Homo habilis.有一些古生物学家认为人种是单一的,即只有能人一种,其他人种都是能人的变异体。Others add a second, Homo rudolfensis.而另外一些古生物学家则认为除能人之外还有第二个人种,即卢尔多夫人。The new fossils found by Dr Leakey and her team may, however, help clear up what is going on.而利基士与她的团队最新发现的人类化石或许可以帮忙理清这些人种之间的关系。One of the new specimens, known as KMN-ER 62000, has a face like the type specimen of Homo rudolfensis, though it seems to be from an adolescent, whereas the type specimen is an adult.这些新发现的样本中有一个被标为KMN-ER 62000的新样本,其脸型与卢尔多夫人样本的脸型相似,Crucially, 62000 has a reasonably well-preserved upper jaw, which the type specimen lacks.尽管62000样本看起来像是来自一个青少年,而卢尔多夫人化石样本则属于一个成年人。A computer reconstruction suggests this upper jaw meshes well with the second of Dr Leakeys discoveries, a lower jaw.关键是,62000样本拥有一个保存尚算完好的上颌,而这正是这一类型的样本所缺少的。She is not suggesting they are from the same individual, since they are of different ages, but they seem to come from the same species, namely Homo rudolfensis.一张电脑重建图显示这一上颌与利基士发现的第二个人种的一个下颌样本十分吻合。由于两块骨头分属两个年龄不同的人,因此利基士并不认为这两块骨头是来自同一个人的,但看起来这两块骨头的主人属于同一人种,即卢尔多夫人。Equally significantly, a different computer reconstruction shows that the upper jaw of 62000 does not match another famous fossil from the area, known as KMN-ER 1802.同样重要的是,另一张电脑重建图显示,62000样本的上颌与KMN-ER 1802样本并不吻合。This was found in 1973 and had previously been thought likely to be the lower jaw of rudolfensis.KMN-ER 1802这块有名的样本化石同样来自这个地区,1973年人们发现它时曾认为这块下颌骨可能属于卢尔多夫人种。What 1802 actually is, is now obscure.现在人们仍旧无法弄清1802样本到底属于哪个人种。It is too different from what this chain of reasoning suggests was the shape of Homo rudolfensis to be explained by sexual dimorphism, unless the sexes differed in this species in ways not seen in any other primate.这一推理链认为它是卢尔多夫人,并以人种的两性差异来解释其外形差异;但这一差异实在太大,除非这一人种的两性差异在其他灵长类动物中见所未见方能自圆其说。But its previous attribution was made because it does not look much like Homo habilis either.但之前人们之所以将其归为卢尔多夫人种是因为它看起来也并不像是能人的下颌。It seems then that at least two, and possibly three species of Homo were stalking the east-African savannah a little under 2m years ago: habilis, rudolfensis and something as yet unnamed.这样看起,在距今不到200万年前,曾有三个人种在东非大草原上生活过:能人,卢尔多夫人,以及一个尚未被命名的人种。The intertwining history of the human family and the Leakey family has just become even more complicated.利基家族一直都致力于研究人类大家族的历史,现在二者之间的关系交织在一起,使历史更加复杂了。 /201402/275345。

  • Most everyone knows that alcohol impairs mental and physiological functions, but what actually goes on at the cellular level when you drink a beer?大多数人都知道啤酒会削弱人的心理和生理功能,但当你喝酒时,在细胞层次上到底在发生着什么?Alcohol interferes with the normal function of your brain cells. Under normal circumstances, each of your brain cells allows various substances, such as sodium, calcium and potassium to permeate its outer cell membrane. Once inside the brain cell, these substances help give the cell stimulus it needs to function properly. Then they leave the cell and allow another set of these substances to begin the cycle again.酒精会干扰大脑细胞的正常功能。在正常情况下,每个大脑细胞允许钠,钙,钾等物质通过外层细胞膜。进入脑细胞后,这些物质能够通过给脑细胞提供必要的刺激来帮助脑细胞正常运作。然后它们离开细胞,让新的一组物质取而代之,开始新的循环。The millions of cells that make up your brain are continually allowing these substances to penetrate their membranes and then expelling these same substances later. All of this action allows the brain to interpret and transport messages. Alcohol consumption prevents sodium from being able to cross brain cell membranes. Once even this part of the cycle breaks down, brain functions become impaired.数以百万计的脑细胞不断地让这些物质穿过细胞膜,之后又将它们排放出去。所有的这些过程都能帮助大脑处理和传输信息。酒精能阻止钠进入脑细胞膜。一旦这部分循环停滞了,脑功能就会受损。You can notice the affects of this break down after a single drink. Even if you’ve had just one drink, your ability to respond to stimulus decreases and your reaction time slows down. If you’re driving, you might see a car stop, and know that you need to slam on the brakes, but the pathway in your brain that processes this information and causes you to respond to it will be working in slow motion.这个循环的停滞会造成多大危害呢?喝过一次酒后你就能注意到。即使你刚喝一杯,你对刺激的反应能力就会下降,你的反应就会变慢。如果你在开车,你可能看到一辆车停下了,而且你知道这时你需要急刹车。但是,大脑中处理信息,让你对此作出反应的神经中枢却在短路。201304/236868。
  • Traditional societies传统社会No beating about the bush不绕弯子Americas best-known geographer shows what there is to learn from early man美国最为知名的地理学家认为我们应该向早期人类学习The World Until Yesterday: What Can We Learn from Traditional Societies?《昨日世界:传统社会有何借鉴之处?》1 JARED DIAMOND has made a name for himself explaining why some societies do well and others do not. In “Guns, Germs and Steel”, his 1997 bestseller, he brushed aside the arrogant view that ascribed Europes dominance to human biology, stressing instead the continents environmental advantages, notably its native wheat and barley and its easily domesticated animals. He followed this up eight years later with “Collapse”, another exhaustive study, this time about how certain societies caused their own demise by ruining the environs that sustained them. Read together, these are civilisation-scale books about survival.贾雷德戴蒙德因为分析了一些社会运行良好一些社会难以为继的原因而名声大噪。他执笔的《炮、病菌与钢铁》是1997年的畅销书。书中,他对 “欧洲社会之所以运行良好,是因为其主导了人类生物学领域” 这一自负论断不屑一顾,在他看来,欧洲大陆的昌盛是因为欧洲优越的环境特别适合种植小麦、大麦以及饲养家畜。八年后,他奉献了耗时良久的又一力作-《崩溃:社会如何选择成败兴亡》。书中主要内容是介绍一些人类社会是如何毁掉自己赖以生存的周遭环境,进而导致自己灭亡的。两本书都是文明层面上有关人类生存的书籍。But they cover only a small portion of the human story. In his new book Mr Diamond, a geographer at UCLA, points out that life on this scale is a recent phenomenon. For most of history human beings lived in small groups as hunter-gatherers. Agriculture began 11,000 years ago; state government not even half as recently.But Mr Diamond, who has spent years studying in the jungles of Papua New Guinea and learning from local tribes people, argues that mankind retains important links to its distant past and can still learn a thing or two from traditional societies.不过,这两本书中写到的只是人类故事的冰山一角。现任教于美国加州洛杉矶分校地理学系的贾雷德.戴蒙德在他的新书中写到人类今天以这种模式生存只是近代才有的一种现象。在历史的大部分时期,人们一直以类似于狩猎者一样聚居的方式生存,毕竟人类开始从事农业生产的历史也才11,000多年,国家政府也是在近代5500多年前才出现。戴蒙德教授花了八年时间呆在巴布亚新几内亚的丛林里,研究当地的部落居民,得出了这样的结论:人类仍旧与遥远的过去保持着重要的联系,传统社会有很多事情值得我们借鉴。Mr Diamond writes, for example, that most societies have held on to some form of religion as a way of maintaining social order, comforting the anxious and teaching political obedience. Tribal societies in New Guinea rarely, if ever, fight over religious matters. These societies also tend to be more multilingual, helpful for diplomacy perhaps, and as it turns out, also a way of protecting against Alzheimers. There are 1,000 different languages in New Guinea alone. Traditional societies resolve disputes by making do entirely without the state. In stark contrast to the American criminal-justice system, the leopard-skin-draped chief of Sudans Nuer people has no role in settling disputes but works to facilitate mediation and calculate traditional forms of compensation.比如,戴蒙德教授在书中就这样写到:大部分人类社会都保留了某种宗教形式,用于维持社会治安、安抚社会急躁情绪、 维持政治统治。不过, 新几内亚的部落居民却从未因为宗教事务发生过冲突。这些原始的部落使用的语言不止一种, 或许这样有助于人们交往。事实上明,使用多种语言也是防治老年痴呆症的好方法。单单在新几内亚就有1000多种语言。传统社会一般在没有国家机器的状态下,就能解决所有冲突。与美国刑事司法系统截然不同的是,苏丹身穿豹纹皮的努尔部落首领没有权力解决纠纷,但是可以采用传统的计算方法核算补偿,从中进行调停。Other things have changed, not all of them for the better. The gluttonous industrialised world could benefit from a more Palaeolithic diet. Traditional societies have hardly a trace of the Wests main non-communicable diseases, such as heart attacks, strokes, diabetes and many forms of cancer—the hallmarks of a diet rich in salt and saturated fat.Thanks to a cuisine of mainly low-sodium bananas, Brazils Yanomamo Indians consume only 50 milligrams of salt a day. One Big Mac would give them a months worth. Tribespeople who adopt a sedentary lifestyle and eat processed food show a sharp increase in the same diseases that afflict Westerners. A third of urbanised Australian aboriginals suffer from type-2 diabetes, and among the Wanigela in Port Moresby, New Guineas modern capital city, the figure is closer to 40%.很多事情已经改变,但是并不尽如人意。 生活在贪婪的工业社会的人们可以多学学旧石器时代的饮食习惯,相信会受益良多。生活在传统社会的人,几乎没人得过类似于心脏病、中风、糖尿病和多种癌症等困扰西方人的常见非传染疾病。这些疾病是食用含盐量高和脂肪饱和食物的有力明。多亏了食用含钠较低的香蕉,巴西的雅诺玛莫印度人一天食盐摄入量只有仅仅50毫克。一个大苹果,就能让他们大快朵颐。那些习惯了长时间坐着工作、食用加工食品生活方式的部落居民,患上那些困扰西方人疾病的几率聚居上升。生活在城里的澳大利亚原住民,有三分之一患上了Ⅱ型糖尿病。生活在巴布亚新几内亚的现代化首都尔贝斯港的Wanigela人,患该类糖尿病的比例将近40%。Mr Diamond is at his most impressed when it comes to tribal family life. He writes of missionary children who prefer the playgroups of traditional societies that bring together children of different ages to the solitary fixation on games that are common back home. Raising children is a communal affair in which the elderly are deeply involved, unlike what happens in most Western countries. He cites studies that show that an African Aka pygmy infant, for example, is looked after by at least seven people and babies in the Efe tribe by as many as 14.At the same time, he writes, children in traditional households seem to enjoy more autonomy. In the Kalahari the !Kung do not resort to physical punishment; instead children are allowed to slap and insult their parents. And New Guinea Highlander children are encouraged to play with knives and with fire, precisely so that they are able to learn from their mistakes.最让戴蒙德教授印象深刻的是部落的家庭生活。他书中写到,比起一回到家一律死盯着电动游戏的孩子相比,传教士的孩子更喜欢在传统社会的操场上玩,在那里,不同年纪的孩子能在一起嬉闹追逐。与大部分西方国家不同的是,在部落家庭里,抚养孩子是集体的事情,老人是这个过程中绝对的主角。有研究显示,非洲地区的阿卡俾格米矮人族的婴儿由至少7人照顾,埃菲社里的婴儿至少由14个人照顾。他书中就引用了这项研究。同时,他还写到,传统家庭长大的孩子似乎想要更多的自主性。喀拉哈沙漠 the Kung人种不会体罚孩子,相反允许孩子侮辱、打骂家长。为了让孩子可以从错误中切身地汲取教训,新几内亚的高地人鼓励孩子玩火,耍刀。In all this, the authors argument is not that we should abandon our modern way of life—he certainly has not—nor does he romanticise traditional people as earth-loving peaceniks. A tribal life can, after all, be nasty and brutish. Few people live past the age of 50, mostly because of curable diseases. For the !Kung, infanticide has been permitted in order to preserve resources in lean times. Bolivias Siriono Indians abandoned their elderly once they became a burden. North American Crow Indians encouraged them to commit suicide. Tribal warfare may kill far fewer than 21st-century mechanised versions, but there is still a constant fear of raids and revenge killings. And a higher percentage of the population dies fighting.作者这么写,不是说人们应该放弃现代生活方式,他也没有这层意思。他也没有把传统社会生活的人们美化成和平分子。毕竟,部落里的生活是不文明而且残酷的。部落里的人很少有活过50的,大部分死于可以治疗的疾病。在the!kung 民族里,收成不好的时节,为了节省资源,人们可以屠杀婴儿。玻利维亚的西瑞诺娜民族会遗弃拖累族群的老人。北美的客如印第安人鼓励孩子杀人。部落争斗中丧生的人大大少于21世纪机械化战争中死亡的人数,但是部落居民一直都有遭受突袭、仇杀之类的担忧。部落人口中很大一部分死于部落斗争。Nor is subsistence living for the faint- hearted. Shortages can mean starvation. Taro, a tropical-root vegetable, is the staple food of the Kaulong people of New Britain, an island off Papua New Guinea. But in the dry season they are forced to scour the forest for insects, snails and unpalatable plants. Toxic wild nuts must be soaked in water for days to leach out the poison.书中,他也没有说胆小鬼有生存的可能。物资短缺可意味着要挨饿。巴布亚新几内亚群岛附近的一座名为新英格兰的岛生活着卡隆民族,他们的主食就是热带根茎蔬菜芋头。但是一到旱季,他们就得去森林捉昆虫,蜗牛以及不怎么美味的植物充饥。他们还会把有毒的野生坚果浸在水里数日,溶解毒性后食用。Mr Diamonds book is mostly a fascinating survey of a rapidly fading world. Only when it tries to pose as a handbook for tribal living does it fall flat. Comparing traditional strategies for maximising crop yields with modern ways of managing financial investments is more banal than original. Our forebears have been around for a lot longer than we have; learning how they did so should be lesson enough.很大程度上来说,戴蒙德教授的新书是对快速消亡世界的一次引人入胜的探寻。如果把这本书当成部落生活的手册,那么这本书就完全算不上好书。把最大程度上提高收成的传统方法与现代金融投资管理方式相比是一种没有创意而且很迂腐的行为。我们的祖先先于我们存在很久,弄明白他们是如何做到这一点就足够我们学一辈子的了。 /201406/304925。
  • When human females are pregnant, theyre advised to stay away from alcohol, for fear of harming the fetus.当人类女性怀时,人们就会建议她们戒酒,以免伤害胎儿。And most parents refrain from giving their infants bottles full of whiskey or beer, for obvious reasons.大多数父母都不会给婴儿接触满瓶的威士忌或者啤酒,原因是显而易见的。But if youre a fruit fly, literally dousing your offspring in alcohol is apparently one of the best ways to protect them from danger, particularly from certain types of wasps.但如果你是一只果蝇,毫不夸张的说,你把后代浸没在酒精中是保护它们远离危险的最好办法之一,特别是这样能避免黄蜂的伤害。How and why?如何以及为什么要这样做?Lets back up a bit.让我们来回顾一下。First, certain types of wasps prey on fruit flies by injecting eggs inside fruit fly larvae.首先,特定类型的黄蜂会将卵注入果蝇幼虫中,以捕食果蝇。Unless an infected larva kills the wasp egg, it hatches and the wasp larva eats its way out from inside the fruit fly larva, killing it.除非受感染的果蝇幼虫杀死黄蜂卵,否则当黄蜂卵孵化出来后,黄蜂幼虫将会由内而外吞噬果蝇幼虫,将其杀死。One way for fruit fly moms to protect against this gruesome fate is to lay their eggs in an alcohol soaked environment, such as fermenting fruit, when they see that parasitic wasps are around.果蝇妈妈为防止幼虫遭受厄运的其中一种办法是,当看到寄生蜂的出现时,将卵产在酒精浸泡的环境之中,例如发酵的水果里。Although alcohol is toxic to fruit flies, its even more toxic to wasps, which, unlike fruit flies, have not evolved a high level of alcohol tolerance.尽管酒精对果蝇有毒,但酒精对黄蜂的毒性更大。与果蝇不同,黄蜂还没有进化成对高浓度酒精的耐受性。So if the larvae eat enough alcohol rich food, it can kill the wasp egg and keep it from hatching.所以如果果蝇幼虫吃了足够富含酒精的食物后,它就可以杀死黄蜂卵并使之不能孵化。Apparently, fruit flies are not the only fly species to use alcohol to protect their young.很明显,果蝇并不是利用酒精来保护幼虫的唯一的蝇类。In fact, it seems that most flies that eat rotting fruit use the alcohol defense against wasps.实际上,大部分的苍蝇都会食用腐烂水果,利用酒精来防御黄蜂。So fruit flies are not unique in this regard, but theyre still mighty impressive.所以果蝇在这方面并不独特,但它们仍然令人印象深刻。 /201311/265286。
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