转自： http://en.wikipedia.org/wiki/Roger_Penrose ... Penrose has written books on the connection between fundamental physics and human (or animal) consciousness. In The Emperor's New Mind (1989), he argues that known laws of physics are inadequate to explain the phenomenon of consciousness. Penrose proposes the characteristics this new physics may have and specifies the requirements for a bridge between classical and quantum mechanics (what he calls correct quantum gravity ). Penrose uses a variant of Turing's halting theorem to demonstrate that a system can be deterministic without being algorithmic . (E.g., imagine a system with only two states, ON and OFF. If the system's state is ON if a given Turing machine halts, and OFF if the Turing machine does not halt, then the system's state is completely determined by the Turing machine, however there is no algorithmic way to determine whether the Turing machine stops.) Penrose believes that such deterministic yet non-algorithmic processes may come in play in the quantum mechanical wave function reduction , and may be harnessed by the brain. He argues that the present computer is unable to have intelligence because it is an algorithmically deterministic system. He argues against the viewpoint that the rational processes of the mind are completely algorithmic and can thus be duplicated by a sufficiently complex computer. This contrasts with supporters of strong artificial intelligence , who contend that thought can be simulated algorithmically. He bases this on claims that consciousness transcends formal logic because things such as the insolubility of the halting problem and Gödel's incompleteness theorem prevent an algorithmically based system of logic from reproducing such traits of human intelligence as mathematical insight. These claims were originally espoused by the philosopher John Lucas of Merton College , Oxford . The Penrose/Lucas argument about the implications of Gödel's incompleteness theorem for computational theories of human intelligence has been widely criticized by mathematicians, computer scientists and philosophers, and the consensus among experts in these fields seems to be that the argument fails, though different authors may choose different aspects of the argument to attack. Marvin Minsky , a leading proponent of artificial intelligence, was particularly critical, stating that Penrose tries to show, in chapter after chapter, that human thought cannot be based on any known scientific principle. Minsky's position is exactly the opposite - he believes that humans are, in fact, machines, whose functioning, although complex, is fully explainable by current physics. Minsky maintains that one can carry that quest too far by only seeking new basic principles instead of attacking the real detail. This is what I see in Penrose's quest for a new basic principle of physics that will account for consciousness. Penrose responded to criticism of The Emperor's New Mind with his follow up 1994 book Shadows of the Mind , and in 1997 with The Large, the Small and the Human Mind . In those works, he also combined his observations with that of anesthesiologist Stuart Hameroff . Penrose and Hameroff have argued that consciousness is the result of quantum gravity effects in microtubules , which they dubbed Orch-OR (orchestrated objective reduction). Max Tegmark , in a paper in Physical Review E , calculated that the time scale of neuron firing and excitations in microtubules is slower than the decoherence time by a factor of at least 10,000,000,000. The reception of the paper is summed up by this statement in Tegmark's support: Physicists outside the fray, such as IBM's John A. Smolin , say the calculations confirm what they had suspected all along. 'We're not working with a brain that's near absolute zero. It's reasonably unlikely that the brain evolved quantum behavior'. Tegmark's paper has been widely cited by critics of the Penrose–Hameroff position. In their reply to Tegmark's paper, also published in Physical Review E , the physicists Scott Hagan, Jack Tuszynski and Hameroff claimed that Tegmark did not address the Orch-OR model, but instead a model of his own construction. This involved superpositions of quanta separated by 24 nm rather than the much smaller separations stipulated for Orch-OR. As a result, Hameroff's group claimed a decoherence time seven orders of magnitude greater than Tegmark's, but still well short of the 25 ms required if the quantum processing in the theory was to be linked to the 40 Hz gamma synchrony, as Orch-OR suggested. To bridge this gap, the group made a series of proposals. It was supposed that the interiors of neurons could alternate between liquid and gel states. In the gel state, it was further hypothesized that the water electrical dipoles are oriented in the same direction, along the outer edge of the microtubule tubulin subunits. Hameroff et al. proposed that this ordered water could screen any quantum coherence within the tubulin of the microtubules from the environment of the rest of the brain. Each tubulin also has a tail extending out from the microtubules, which is negatively charged, and therefore attracts positively charged ions. It is suggested that this could provide further screening. Further to this, there was a suggestion that the microtubules could be pumped into a coherent state by biochemical energy. Roger Penrose in the University of Santiago de Compostela to receive the Fonseca Prize . Finally, it is suggested that the configuration of the microtubule lattice might be suitable for quantum error correction, a means of holding together quantum coherence in the face of environmental interaction. In the last decade, some researchers who are sympathetic to Penrose's ideas have proposed an alternative scheme for quantum processing in microtubules based on the interaction of tubulin tails with microtubule-associated proteins, motor proteins and presynaptic scaffold proteins. These proposed alternative processes have the advantage of taking place within Tegmark's time to decoherence. Hameroff, in a lecture in part of a Google Tech talks series exploring quantum biology , gave an overview of current research in the area, and responded to subsequent criticisms of the Orch-OR model. In addition to this, a recent 2011 paper by Roger Penrose and Stuart Hameroff gives an updated model of their Orch-OR theory, in light of criticisms, and discusses the place of consciousness within the universe. Phillip Tetlow, although himself supportive of Penrose's views, acknowledges that Penrose's ideas about the human thought process are at present a minority view in scientific circles, citing Minsky's criticisms and quoting science journalist Charles Seife 's description of Penrose as one of a handful of scientists who believe that the nature of consciousness suggests a quantum process. ...
也谈大牛系列之，Roger Tsien---------- 天才是怎样炼成的 也谈大牛系列之，Roger Tsien （一） ---------- 天才是怎样炼成的 （ 说明，此篇文章完全是狗尾续貂大牛lanceandfei的系列介绍，格式上大家一看便知。文中故事和时间很多属口头相传，不准之处请见谅。） 说此人 （Roger Tsien)，偶可是彻夜难眠-----大大大牛呀。从名字上看就知道这是个亚裔。估计大家可能都知道此人，提起 Calcium indicator, GFP re-engineering，更是无人不知。如果还不知道就得去HHMI的网上，或他自己的实验室的网上去敬仰一把吧！ Roger Tsien 在美国出生，是中国科学家钱学森的嫡系侄儿 （遗传学不得不让人相信，聪明是有genetics的基础）。我可不是要说他的族谱（虽然这里也有很多有趣的故事），而是说他的生物学贡献，尤其是在神经生物学和细胞生物学的贡献。牛人就是牛人啊，此人是我心目中真正的不世出的大师。 从小 Roger 身体不太好，只好待在地下室艳慕兄弟们在外栽花逗草，这也让他养成了对光和颜色的偏爱。他将来的研究方向可能与幼时的经历有关。他在Havard上大学之前就得了西屋奖 （1968 年，卖个关子，大家猜猜时什么？和image也有关系，very impressive）。大学里他选择了有机化学--按照他的话说--因为父亲的关系，家里的人都喜欢enigeer相关的专业上。但是好的专业，如 electrical engineering 已被兄长选取，为了不under their shadow，他选了有机化学--这注定了他对分子的engineering的工作--one of the best and most ingenious works. 在Havard学业结束之后，出于对科学的热爱Roger选择继续深造。应该注意的是，此时的Roger已经有研究神经生物学的想法---但是到哪儿深造呢？Roger不想去MIT，其中的一个原因是到那儿会和自己的兄长撞衫。Roger一直都有和兄辈相竞争的好强之心--他争取了一个私人基金会的奖学金资助他去Cambridge,UK深造。他的兄长Richard在Oxford取得博士，至少这样俩人是并驾齐驱的 （仅个人想法,无需深究）。 到英国学什么？虽然roger想向neuroscience发展，但命运不是由他完全掌握。私人基金会通过剑桥帮他联系了导师--这有点像国内以前的研究生入学---导师是指定的，没有rotation制度。 按照Roger自己的说法，那时候没有internet，到英国前他几乎都不知道导师的确切研究方向。到了英国他终于见到了导师，这里也有些故事。 Anyway，长话短说，他的PhD导师是Richard Keynes，一位著名的muscle电生理学家。Richard Keynes 是Nobel 奖得主Alan Lloyd Hodgkin的得意门生，对膜电位和膜通道有极深的造诣。虽然Roger有点不太喜欢研究muscle （可能因为肌肉没有神经元那么神 奇？），但事实上膜电位和膜通道的原理对控制muscle和neuron是一致的。更好的是导师Richard Keynes是一个传统的gentleman，他几乎让roger做他自己想做的事。就在当graduate student的时候，roger有了image brain和image动作电位的想法--正是这种想法bring most of the current neuroscientists into the imaging era. 在Richard Keynes的实验室待了三年（1975-1978）Roger顺利得到了PhD。于1978-1981在Timothy Rink（Cambridge, UK) 的实验室做了短暂的postdoc。在Roger将开始了他在Berkeley独立的实验室的工作前，他已经开始了不平凡的revolutionary的 工作-----trying to synthesize voltage sensitive chemicals to imaging action potential。各位看官可能会问--不对呀，Roger不是开始合成calcium indicator的吗？怎么会是voltage sensitivedye呢？ 殊不知roger的第一个project确实是合成voltage sensitive dye。 这里的故事为大多数人所不知，且听我慢慢道来。 70年代早中期， 钙离子的关键作用还没有深入人心 ---- in fact the very existence of selective calcium channel is not well established and well accepted ！钙离子只被认为存在一些特殊的细胞中。相对而言，the mechanism of action potential 早已被Roger的师祖Hodgkin (及Huxley) work out, 而且被证明广为存在 --- 被认为神经网络的基石之一。作为天才的roger，一个人在小黑屋里冥思苦想了三天三夜 （纯粹为搞笑而已）--- 设计了合成voltage senstive dye的方案。 Roger reasoned ------ 一个很好的合格的有接班人性质的voltage sensitive dye必须以下具备三个特性：1. 必须能target到membrane上 (废话，要不然怎么感受到只有在膜上才存在的动作电位的变化！）。 2. 必须能感受到膜电位的变化（废话，要不然怎么叫voltage sensitive！） 。3. 必须能convert 膜电位成可以detect的光信号 （废话，要不然怎么叫dye ！）。 以上三个特性看似trivia，其实包含了essential的理念---关键是怎样把这些特性在化合物上实现 ！对于特性1，roger认为只要有足够的 hydrophocity （如苯环）就可以达到-----亲脂的化合物喜欢membrane。 对于特性2则必须有voltage sensor -- --类似于离子通道的S4 loop 的voltage sensor，这也不难，只要有charge （如 lysine or glutamate)。 对于特性3，可以把已知的organic dye加上去 （如 fluoroscin， rhodamine），希望它们的光谱会couple to voltage change。 Roger马不停蹄的在电生理的实验室开始了他legendary的voltage sensitive dye 的合成工作。合成出来的dye却很不不尽人意有的dye不是没有detectable的voltage的敏感度，要不就是非常容易bleach，或toxic to cells。事实上，要检测合成的产物是否有voltage dependent 的光特性也很不容易。试想之----- 动作电位的时程是毫秒级的， 动作电位的amplitude在100 mV左右， voltage senstive的颜料需要注射到细胞内-----这就需要非常敏感的光检测技术和相应的膜片钳技术（Voltageclamp). 这在现在都很困难，更别提70年代了。 总之，尽管不如意，Roger还在辛勤的不知疲倦的合成着，但这是意料之外的事发生了------ 1976 年底有人已经合成出voltage sensitive dye，并且demostrate可以用来image动作电位------ Roger 的第一个project竟被人screw了！ 原来，Roger的同门师兄Larry Cohen （已经在 Yale) 也有同样的想法----不同的是Larry没有太多的化学合成的背景。Larry采用的方法是brute force的screen ------- 有点像现在的small library drug screen------------实际的操作上是狂查Sigma catalog上所有和发光相关的化合物，然后直接注射到枪乌贼的大轴突里（这大轴突就是Hodgkin 及Huxley用来研究动作电位的classic的preparation)。 就这样注射了一两百个化合物 （花了postdocs和graduate students countless hours），居然真让他们发现了first generation的voltage sensitive dye （注1）。 更为搞笑的是，据说Larry发现的dye和Roger de novo 合成的只差一两个苯环或亚基---------但是Roger的dye的signal却是10倍以上的小，没有办法被检测到---------甭提Roger有多郁闷了（注2）。Roger天人交战了三天，决定放弃他辛苦做了2年的project, 一方面因为他不是第一个做成voltage sensitive dye的，另一方面他觉得voltage sensitive dye的signal to noise ratio在短期内不可能有大的突破（deltaF/F~ 0.5%)，还有一个更重要的原因是他有了个新的主意-----这回他决定一定要成功......... 注1： J Membr Biol. 1977 May 6;33(1-2):141-83 Changes in absorption, fluorescence, dichroism, and Birefringence in stained giant axons: : optical measurement of membrane potential. Ross WN, Salzberg BM, Cohen LB, Grinvald A, Davila HV, Waggoner AS, Wang CH. 注2：笔者对Roger向来是无比敬仰的，这里也不的不对Roger的痛苦感同身受。现在无数的signal transduction pathway 都是靠人力screen出来的。同时无数的fluorescent protein的engineering也是靠人力（sometimes 日本人）找到。所以有的时候你要是有足够的人力和物力，你可以screw many smarter persons （当然screen的essay必须是solid的）。 要appreciate Roger天才般的工作，有必要谈谈molecule imaging 的重要性及好处。其实很多例子都是来源于Roger的pioneer的illustration。我们重新digest一遍说不定能帮助有些不熟悉imaging领域朋友的研究。 总结来说，imaging特别适用于cell biology 或neuroscience，因为所有的organelle或细胞都是highly non-homogenous。imaging的方法有相对于biochemical的手段而言有spatial，temporal resolution的优势。同时，imaging 的方法 could be specific（比如不同的蛋白或脂类）， tunable （比如不同颜色），non-invasive （比如活体）and paralleled （比如许多不同的细胞或组织一起）。以上的每一点都可以展开讲上三天三夜。Again, 很多好处大家可能都了解了，版上也有不少这方面的专家。 但是试想一下在70年代末，所有的tools都是一片空白的时候，Roger一个人就有了这样的vision，而且他还是一个化学为主的graduate student！ 话说回Roger放弃了他imaging动作电位的project，夏天的一日他到了美国东部的海洋生物实验室（MBL, Woods Hole in MA) 闲逛。在那儿正聚集了全世界最好的电生理学家----因为在70年代patch clamp还没有发明，电生理学家只能记录大的海洋生物的神经细胞或是肌肉的电信号，于是夏天的Woods Hole吸引了一堆的大牛和小牛们来做实验。那几日，大牛和小牛们讨论最热门的话题就是用刚发现不久的水母钙荧光蛋白来研究钙信号和secretion或contraction的关系。事实上R. LLINAS已经从1972年开始用水母钙荧光蛋白记录钙信号 （注1）。Roger, 当时还是小牛中的小牛，对此很感兴趣。由于他的化学背景，他大胆的问了一个大大牛似乎too simple， sometimes naive的问题----水母钙荧光蛋白对于钙离子和镁离子的选择性。这其实是一个蛮重要的问题，因为细胞内的自由的镁离子的浓度比钙高出甚多。大大牛对这个问题似乎并不注意，随口dismiss了Roger的问题说电生理的证据表明没有镁离子通过细胞膜。 从这次的Woods Hole 之旅，Roger认识到了自己将来的方向-------生物领域的人大多数不喜欢也不敢touch合成化学，而化学领域的大牛们有常常不知道生物领域的重要问题及实验困难所在--------这就给了他这位当时的小牛中的小牛unique的机会成为横跨领域的大大牛！ 注1： LLNAs, R., R. J. BLINKS, and C. NICHOLSON. 1972. Calcium transients inpresynaptic terminal of squid giant synapse: detection with aequorin. Science (Wash. D.C.). 176:1127 回到Cambridge，UK后，Roger潜心开始合成organic dye for calcium。因为这时，free calcium ion已经隆重的登上了历史舞台，成为了重要的second messenger。按照Roger的话来说 It is scarcely necessary any longer to stress the importanceof intracellular free Ca2+ as a second messenger for external stimuli and as a regulatory ion. (注1)。确实，此刻的calcium已经被认为是key molecule for secretion，fertilization。同时，他兄长（Richard, at Yale)的工作也implicate钙离子的在骨骼肌和心肌收缩的essential function。这样，calcium的signaling 就有了非常重要physiological和clinical的value。于是Roger 在此时timely的指出A major technical challenge has been to devise satisfactory means for nondestructively measuring intracellular free Ca2+ with good time resolution (注1) 。应该注意的是，Roger并没有mention anything related to spatial resolution，为什么？ 大家猜猜。 对于新的calcium indicator，Roger首先就开始考虑Ca离子和Mg离子的选择性的问题-----他选用了EGTA，一个著名的Ca离子的buffer作为start point。 因为EGTA螯合剂的孔径不适合Mg离子的binding，所以这就potential降低了背景Mg离子的干扰。但是EGTA binding Ca离子的速度太慢，而且pka也不合适 （pka 决定了proton （H+） binding的pH值。在生理情况下～pH 7.3，proton 喜欢binding EGTA-----从而会干扰了钙离子的binding），Roger rationally 的先合成了BAPTA，一个现在也广为使用的high speed Calcium Buffer，然后又在此基础上合成了improved的quinolines。 (注1) 就这样，Roger将以1980 年(注1)的的文章 （唯一作者）结束了在英国的求学。这篇文章里的calcium dye并不完美，比如吸收和发射光谱太靠近UV range （potential badfor cells and problems with autofluroscence），而且signal to noise ratio 也 不太近人意。这篇文章的引用率也没有他下一篇的JBC高，但是Roger在文章里demostrate了rationale合成indicator的concept （比如indicator的calcium bindingaffinity 可以readily tuned)，而且他也correctly指出了现有存在的问题及可能解决的方法。这样的文章可能是science发展的typical的流程-----有时你可能do everything right，但是你并不能立马得到完美的结果--------你可能所需的是keeptrying and trying，over and over again-----------机会是喜欢有准备的头脑的。 那么机会喜欢Roger的头脑吗？ Berkeley， I am coming！ 注1： Tsien, R.Y. (1980) New calcium indicators and buffers with high selectivity against magnesium and protons. Biochemisty 19: 2396-2404
Wenfei Fan wins Roger Needham Award 2008 and Yangtze River Scholar Award The Roger Needham award is awarded by the British Computer Society for distinguished research contribution in computer science by a UK based researcher within ten years of their PhD. The Yangtze River Scholar Award (also known as the Chang Jiang Scholar Award), is awarded by the Ministry of Education of China. It is considered one of the most prestigious academic awards given by the People's Republic of China. Professor Wenfei Fan is, simply put, one of the top all-around database researchers in his generation. He has made substantial contributions both to the theory and to the practice of a subject. Wenfeis PhD work opened up a new field of constraints for semi-structured data, which eventually led to the study of constraints for XML, now a mature area well-represented in the full spectrum of database research, from theory to practice to standards. The continuation of this work, which started when Wenfei was at Bell Labs and continued after his arrival to Edinburgh, has now embraced XML and its various schema formalisms, and has broadened to the static analysis of XML query languages. It has resulted in a succession of theoretical papers of outstanding quality and has also influenced the design of XML schema. The general goal of Wenfeis work has been to bring the efficiency and functionality of databases to bear on data on the web. In the past few years his research has resulted in several practical developments: A system for efficiently mapping relational databases into an XML documents with a specified type using a generalization of attribute grammars and a new theory of tree transducers. This is currently in use for generating exportable scientific data sets. A system for imposing secure views of an XML document based on the DTD of that document. The use of partial evaluation (borrowed from functional programming) for the efficient evaluation of boolean queries on distributed data. A method of data cleaning based on conditional functional dependencies,which Wenfei proposed for this purpose. This is a nice application of his early ideas on constraints in databases to the highly practical problem of data cleaning (unclean data is estimated to cost US companies alone more than billions of dollars a year). Wenfei is part of the DatabaseGroup at the Laboratory for Foundations of Computer Science . Edinburgh is proud to claim 3 out of the the 5 Roger Needham Awards so far. In addition to Wenfei, Professor Jane Hillston was awarded the prize in 2004 (she was the first researcher in the UK to win this prize) and in 2006 the prize went to Edinburgh graduate, Andrew Fitzgibbon . 以上信息来源于 https://www.inf.ed.ac.uk/events/news/wenfeifan.html Wenfei Fan(University of Edinburgh)
感谢 Roger 教授 我与明尼苏达大学的 Roger 教授相识于 2002 年。当时，他受教育部春晖计划资助，特邀回国参加 2002 年 6 月在杨凌西北农林科技大学举行的农业与生物系统工程科技教育发展战略论坛暨第五次全国高等学校农业工程类学科专业教学改革学术研讨会。 Roger 教授怀着一腔报国之心，开始了他频繁的在美国与中国之间飞来飞去，开展了多项卓有成效的合作研究和讲学计划。也是从 2002 年始，我开始与 Roger 教授（代表海外华人农业与食品生物工程师协会， AOCAFBE ）联系，寻求合作创办国际英文刊的探索。 Roger 教授在南昌大学受聘为教育部长江学者，把他在美国前沿的研究输送回国，帮助国内的研究与国际同步。 Roger 教授在明尼苏达大学担任食品与生物工艺系的系主任，每年科研经费数百万美元，因为有充足的科研经费，在他麾下有一个 40 多人的研究团队，其中大部分是为国内培 养的 博士 和 博士后。为帮助国内科研工作者把科研成果传播到国际科学界，他发起和推动与中国农业工程学会合作创办国际英文刊，并用自己的科研经费支付薪金让他的博士后承担创办英文刊的大量工作。 Roger 教授所做令人敬仰，值得称赞。从国家社会宏观层面，我们应该感谢 Roger 教授。 从我个人的角度， Roger 教授也很值得感谢。因为希望购买一些英文原著，但在国内难以买到，自然就希望找 Roger 教授帮忙。第一次是因为爱人在中国社会科学院世界经济与政治研究所读博士期间，因借图书馆的一本英文原著不知去向，只好求助 Roger 教授帮忙在美国购买带回。从美国买回所借的英文原著后，后来发现爱人凯 利斯 小姐（ Ms Careless ）当时在社科院图书馆借书时，办完借书手续后就走了，书却留在图书馆，馆员以为是读者送还的书就归架了。第二次是我希望购买一些有关英文科技论文写作与编辑方面的书籍，这次 Roger 教授又帮我购得四本并送到北京。两次购书花去 Roger 教授近 200 美元，他一分没收，全当他的捐赠和贡献了。且不论钱之多少， Roger 教授忙于科研、教学、管理、指导研究生、参加学术会议等，还能挤出宝贵的时间来帮我办理购书者等琐细之事，实属不易，也难能可贵。我特别感谢 Roger 教授，不仅仅因为免费为我购书，更因他拳拳报国之心。 Roger 教授担任即将创刊的国际英文刊主编，期待国际英文刊在 Roger 教授的领导下快速成长，早日进入 SCI/EI 等国际知名检索体系，创立品牌，更好的为更多人服务。衷心的感谢 Roger 教授！我们会把更多更深的感谢留待将来。 附： Roger 教授购赠的有关英文论文写作原著书目 1 Robert A. Day . How to Write and Publish a Scientific Paper. 6th Edition (Paperback). Greenwood Press, March 30, 2006. 2 Michael Alley. The Craft of Scientific Writing. 3rd Edition, Springer-Verlag, 1996. 3 Anne Stilman . Grammatically Correct: The Writer's Essential Guide to Punctuation, Spelling, Style, Usage and Grammar (Hardcover). Writer's Digest Books; 1 edition, August 1997. 4 Vernon Booth . Communicating in Science: Writing a Scientific Paper and Speaking at Scientific Meetings (2nd Edition) (Paperback). Cambridge University Press; 2 edition, April 30, 1993.
标签: Roger
