Sample records for umbrohutrje vimalusi viki-nisu
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Clinical evaluation of complete solo surgery with the "ViKY®" robotic laparoscope manipulator.
Takahashi, Masahiro; Takahashi, Masanori; Nishinari, Naoto; Matsuya, Hideki; Tosha, Tsutomu; Minagawa, Yukihiro; Shimooki, Osamu; Abe, Tadashi
2017-02-01
Advancement in both surgical technique and medical equipment has enabled solo surgery. ViKY ® Endoscope Positioning System (ViKY ® ) is a robotic system that remotely controls an endoscope and provides direct vision control to the surgeon. Here, we report our experience with ViKY ® -assisted solo surgery. We retrospectively examined 25 cases of solo surgery TAPP with ViKY ® . ViKY ® was setup by the surgeon alone, and the setup duration was determined as the time at which the side rail was positioned and that when the endoscope was installed. For assessing the control unit, the number of false movements was counted. We compared the operative results between ViKY ® -assisted solo surgery TAPP and the conventional method with an assistant. The average time to set up ViKY ® was 7.9 min. The average number of commands for ViKY ® during surgery was 98.3, and the average number of errors and no response of control unit was 7.9. The mean duration of surgery was 136 min for the ViKY ® group, including the setup time, and 117 min for the conventional method. No case required an assistant during the operation. There was also no difference between the two groups with regard to postoperative complications and the rate of recurrence. ViKY ® proved reliable in recognizing orders with very few failures, and the operations were performed safely and were comparable to the conventional operations with assistants. Solo surgery with ViKY ® was beneficial in this clinical evaluation.
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NASA Astrophysics Data System (ADS)
Purcell, E. M.
2014-11-01
This is a talk that I would not, I'm afraid, have the nerve to give under any other circumstances. It's a story I've been saving up to tell Viki. Like so many of you here, I've enjoyed from time to time the wonderful experience of exploring with Viki some part of physics, or anything to which we can apply physics. We wander around strictly as amateurs equipped only with some elementary physics, and in the end, it turns out, we improve our understanding of the elementary physics even if we don't throw much light on the other subjects. Now this is that kind of a subject, but I have still another reason for wanting to, as it were, needle Viki with it, because I'm going to talk for a while about viscosity. Viscosity in a liquid will be the dominant theme here and you know Viki's program of explaining everything, including the heights of mountains, with the elementary constants. The viscosity of a liquid is a very tough nut to crack, as he well knows, because when the stuff is cooled by merely forty degrees, its viscosity can change by a factor of a million. I was really amazed by fluid viscosity in the early days of NMR, when it turned out that glycerine was just what we needed to explore the behavior of spin relaxation. And yet if you were a little bug inside the glycerine, looking around, you wouldn't see much change in your surroundings as the glycerine cooled. Viki will say that he can at least predict the logarithm of the viscosity. And that, of course, is correct because the reason viscosity changes is that it's got one of these activation energy things and what he can predict is the order of magnitude of the exponent. But it's more mysterious than that, Viki, because if you look at the Chemical Rubber Handbook table you will find that there is almost no liquid with viscosity much lower than that of water. The viscosities have a big range but they stop at the same place, I don't understand that. That's what I'm leaving for him...
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Model-Free Views of Deep Inelastic Scattering
NASA Astrophysics Data System (ADS)
Schwinger, Julian
2014-11-01
Perhaps I should point out first that my choice of topic was dictated by the injunction that the nature of this symposium should revolve around subjects that might be conceivably of interest to Viki. Viki has, along with most high energy physicists been very interested in the subject of deep inelastic electron scattering. With his characteristic attention to directly visualizable approaches to physical phenomena, he has dealt with this in terms of rather specific models, attempting then to give very elementary explanations of these fascinating phenomena. I thought he might be interested to see the other side of the coin, namely, the extent to which one can correlate and comprehend these physical effects without the use of specific models. I think this may lend a certain useful balance to the way things are looked at these days. So my remarks are directed to Viki but you're all welcome to eavesdrop...
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Abstractness and emotionality values for 398 English words.
Guido, Gianluigi; Provenzano, Maria Rosaria
2004-06-01
This study is aimed to replicate Vikis-Freibergs' classic study (1976) on the values of vividness for French words. Vividness resulted from the concreteness and the emotionality values of words, here defined, respectively, as referring to something that can be experienced through senses and that can arouse pleasant or unpleasant emotions. 398 English words were rated on two different scales, Abstractness and Emotionality, by a group of English native speakers and also by a group of Italian subjects who used English as a second language. Results show a low correlation between the concreteness and emotionality ratings in line with Vikis-Freibergs' previous study of French words (1976). A negative correlation between Abstractness and Emotionality was observed for British data but a slightly positive correlation for the Italian data.
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A dithiolate-bridged (CN)2(CO)Fe-Ni complex reproducing the IR bands of [NiFe] hydrogenase.
Tanino, Soichiro; Li, Zilong; Ohki, Yasuhiro; Tatsumi, Kazuyuki
2009-03-16
A dithiolate-bridged dinuclear Fe-Ni complex, which has the desired fac-(CN)(2)(CO) ligand set at iron, has been synthesized. Its CN/CO bands in the IR spectrum reproduce those of the Ni-A, Ni-B, and Ni-SU states, which indicate that these octahedral Fe(II) centers have similar electronic properties. This result verifies the assignment of a (CN)(2)(CO)Fe(II) moiety in the active site of [NiFe] hydrogenase.
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2000-01-12
One of a new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. The stamp, shown here, is the Space Shuttle Columbia, first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history. Taking part in the "First Day of Issue Ceremony" were astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson
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2000-01-12
A new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. Taking part in the "First Day of Issue Ceremony" were astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson. Among the stamps issued is one of Space Shuttle Columbia (upper left corner), first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history
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2000-01-12
A new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. Shown taking part in the "First Day of Issue Ceremony" are (left to right) astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson. Among the stamps issued is one of Space Shuttle Columbia, first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history
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2000-01-12
A new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. Shown taking part in the "First Day of Issue Ceremony" are (left to right) astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson. Among the stamps issued is one of Space Shuttle Columbia, first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history
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2000-01-12
A new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. Taking part in the "First Day of Issue Ceremony" were astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson. Among the stamps issued is one of Space Shuttle Columbia (upper left corner), first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history
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2000-01-12
One of a new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. The stamp, shown here, is the Space Shuttle Columbia, first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history. Taking part in the "First Day of Issue Ceremony" were astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson
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2000-01-12
One of a new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. The stamp, shown here, is the Space Shuttle Columbia, first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history. Taking part in the "First Day of Issue Ceremony" are (left to right) astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson
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2000-01-12
One of a new series of U.S. Postage stamps, The 1980s, is unveiled at the KSC Visitors Complex. The stamp, shown here, is the Space Shuttle Columbia, first launched in April 1981. This collection of stamps is the ninth in the Post Office's "Celebrate the Century" commemorative series honoring the last 100 years of American history. Taking part in the "First Day of Issue Ceremony" are (left to right) astronaut Richard Linnehan, U.S. Representative, 15th Congressional District, Dave Weldon, U.S. Postal Service District Manager Viki Brennan, Center Director Roy Bridges and President of the Visitor Complex Rick Abramson
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The World As Quarks, Leptons and Bosons
NASA Astrophysics Data System (ADS)
Gell-Mann, Murray
2014-11-01
I hope that my few disconnected remarks will not appear too inadequate after that magnificently organized presentation by T. D. Lee. I remember very well the time, more years ago than I would like to count, when I faced the choice between graduate school and M.I.T. and suicide. I chose to come here, actually, after a difficult decision. That it turned out to be the right decision became clear when I met the man who had hired me as his assistant, the man that we are gathered here to honor today--a man known all over the world by his nickname, "Viki". I had better be careful, especially after the previous speech, when I do get to discussing elementary particles, not to dwell too long on symmetry breaking by the vacuum. I understand that the press is represented here and I can visualize in the Boston newspapers the headline "M.I.T. Physicist Honored by Speeches About Nothing"...
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Cryopreservation of lipid-rich seeds: effect of moisture content and cooling rate on germination.
González-Benito, E M; Pérez-García, F
2001-01-01
The effect of fast and slow cooling on germination of seeds from two Brassicaceae species (Eruca vesicaria (L.) Cav., Brassica napus L. var. oleifera (Moench) DC cv. Bingo) and cypselas from three Compositae species (Onopordum nervosum Boiss., Onopordum acanthium L., Helianthus annuus L. cv. Viky) at different moisture contents was studied. Seed lipid content (dry weight basis) ranged from 15% (O. nervosum) to 41% (H. annuus). For each species, seeds with four moisture contents were cryopreserved either by direct immersion in liquid nitrogen or by previous cooling at 10 degrees C/min from room temperature to -50 degrees C. In three species (E. vesicaria, B. napus, and H. annuus) germination of air-dried (6.2-8.9% moisture content) seeds cooled by direct immersion in liquid nitrogen was not significantly different from germination of control seeds (air-dried, non-cooled). In the two Onorpordum species the best response among cooling treatments was observed when air-dried seeds were slowly cooled.
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Volbeda, Anne; Martin, Lydie; Barbier, Elodie; Gutiérrez-Sanz, Oscar; De Lacey, Antonio L; Liebgott, Pierre-Pol; Dementin, Sébastien; Rousset, Marc; Fontecilla-Camps, Juan C
2015-01-01
Catalytically inactive oxidized O2-sensitive [NiFe]-hydrogenases are characterized by a mixture of the paramagnetic Ni-A and Ni-B states. Upon O2 exposure, enzymes in a partially reduced state preferentially form the unready Ni-A state. Because partial O2 reduction should generate a peroxide intermediate, this species was previously assigned to the elongated Ni-Fe bridging electron density observed for preparations of [NiFe]-hydrogenases known to contain the Ni-A state. However, this proposition has been challenged based on the stability of this state to UV light exposure and the possibility of generating it anaerobically under either chemical or electrochemical oxidizing conditions. Consequently, we have considered alternative structures for the Ni-A species including oxidation of thiolate ligands to either sulfenate or sulfenic acid. Here, we report both new and revised [NiFe]-hydrogenases structures and conclude, taking into account corresponding characterizations by Fourier transform infrared spectroscopy (FTIR), that the Ni-A species contains oxidized cysteine and bridging hydroxide ligands instead of the peroxide ligand we proposed earlier. Our analysis was rendered difficult by the typical formation of mixtures of unready oxidized states that, furthermore, can be reduced by X-ray induced photoelectrons. The present study could be carried out thanks to the use of Desulfovibrio fructosovorans [NiFe]-hydrogenase mutants with special properties. In addition to the Ni-A state, crystallographic results are also reported for two diamagnetic unready states, allowing the proposal of a revised oxidized inactive Ni-SU model and a new structure characterized by a persulfide ion that is assigned to an Ni-'Sox' species.
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NASA Astrophysics Data System (ADS)
Delbrück, Max
2014-11-01
I am wondering how to address you, Viki, on this tremendous occasion, dedicated to commemorate your approaching "graduation from college". Like many of us here assembled, you will have to think of a career to choose after this "graduation". Perhaps the most appropriate form of address would be the way the young Goethe was instructed to address his grandfather, namely, "Erhabener Grosspapa!" That could be translated "Exalted Granddaddy", but the flavor is not quite the same. I'll start out with some comments on Stan Ulam's talk. He invited us to speak up in the discussion to his talk, but I prefer to do it now when I have the floor to myself, so he can't talk back. There are several of his quotes that I want to comment on. One quote from Fermi on some theory that had been confirmed better than he, Fermi, thought the theory had any business of being that good. To anybody that works in biology and is aware of the fact that our brain evolved to help us get along in the cave, it is utterly miraculous and completely incomprehensible that this brain is capable of doing science at the success rate at which it is doing it. This is an aspect that mathematicians and physicists and most scientists tend to ignore. But it is one that is very much in the minds of those who are trying to understand more deeply the nature of our perceptive and cognitive capabilities from the point of view of biology...
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NASA Astrophysics Data System (ADS)
Weisskopf, Victor F.
Once Nino came to my office to tell me about his ideas of studying lepton pair production at PS. I was still not Director General, but Research Director at CERN. In addition to (e+e-) and (μ+μ-) pairs, he wanted to search for (e±μ∓) pairs as a signature of a new lepton carrying its own lepton number. He told me that if such a lepton existed with one GeV mass, it would have escaped detection in hadron accelerator experiments for two reasons: i) it would decay with a lifetime of order 10-11 sec and ii) because there is no π → μ mechanism for such a heavy new lepton: for its production a time-like photon would be needed. Time-like photons could be produced in hadronic interactions: for example in (bar{p}p) annihilation. This was before Lederman-Schwartz and Steinberger had discovered the two neutrinos. To think of a "sequential" Heavy Lepton and to work out the possible ways to get it in a hadron machine was for me extremely interesting Nino had just finished his first high precision work on the muon (g-2). It was some time after the Rochester Conference in 1960. I gave Nino the following suggestion: if you want to search for something so revolutionary as a Heavy Lepton carrying its own lepton number you should work out a proposal for a series of experiments where the study of lepton pairs (e+e-) and (μ+μ-) could be justified in terms of physics accepted by the community. In addition a high intensity antiproton beam was needed. He came later to tell me that he had two very good friends, both excellent engineers: Mario Morpurgo and Guido Petrucci. A very high intensity antiproton beam could be built to study the electromagnetic form factor of the proton in the time-like region. If the proton was "point-like" in the time-like region, the rate of time-like photons yielding (e+e-) and (μ+μ-) pairs could be accessible to experimental observation, thus allowing to establish some limits on the new Heavy Lepton mass, or to see it, via the (e±μ∓) channel. The "official" theme was: to establish if the proton had a structure or not in the time-like region. Thus a powerful system able to detect (e+e-) and (μ+μ-) pairs could be built. Nino established in 1963 the existence of a time-like structure of the proton studying the (e+e-) channel and in 1964 studying the (μ+μ-) channel. The set up was able to do what he wanted: a simultaneous detection of electrons and μ pairs, therefore (e±μ∓) as well. Unfortunately the proton was not a point-like particle in the time-like region and therefore the source of time-like photons originated in (bar{p}p) annihilation was very depressed. In fact, using the (e+e-) and the (μ+μ-) channels, Nino established that at 6.8 (GeV/c)2 time-like four momentum transfer, the crosssection was 500 times below the expected point-like value. This result had attracted a lot of attention. Bogoliubov was very interested when in 1964 Nino went to Dubna to present the (μ+μ-) results at the International Conference on "High Energy Physics". Yang had a model that predicted a point-like structure of the proton in the time-like region. I called this series of experiments as measuring the "heartbeat of the proton". Of course there were no (e±μ∓) events, neither in the (bar{p}p) nor in the (μ-p) channel. Nevertheless a series of experiments was performed on "standard" physics, such as the discovery of many rare decay modes of mesons and the measurement of the (φ-ϕ) mixing. All these experiments could be done because Nino had invented what is now known as the "preshower" method to reject with high efficiency pions in favor of "electrons". Once it was clear that in hadronic interactions there are very few time-like photons, he asked me if I would give green light in order to consider the use of the (e±μ∓) technology in the newly being developed Frascati (e+e-) method would have been the best in order to see if a Heavy Lepton carrying its own lepton number existed. Of course he got the green light and in 1970 he got the first limit on the Heavy Lepton mass together with a series of high precision QED measurements. But one story I will never forget in connection with the "heartbeat of the proton". After he succeeded with his friends Mario (Morpurgo) and Guido (Petrucci) to build the highest intensity antiproton beam at CERN, Nino came to my office and said more or less the following: "Viki, by changing the voltage of the electrostatic separator and a few other trivial details, in one night, I will be able to establish if the antideuteron exists with the correct expected deuteron mass". I told him that this was an experiment where he would get the Nobel prize if he found nothing. "But, there is a but", I added. "If you do not succeed in one night and if you destroy the beam, then I will not defend you. My green light is only valid if you really can check the existence of the antideuteron in a single night". Next morning, when I arrived at CERN, Nino was there with his graph where the antideuteron signal was exactly where it was expected to be. I remember the year, 1965, not the day. It was (and is) the birthday of Peter Standley who was at that time the PS Division Leader. I called him in my office and the antideuteron discovery at CERN was my and Nino's gift to our mutual friend Peter. I decided not to have a press-release and Nino agreed. A few weeks later we read in the newspaper that the antideuteron had been discovered by Lederman and Ting in the United States. They had decided to have a press-release. Nevertheless Nino's paper in Nuovo Cimento preceeds Leon's and Sam's publication in Physical Review.
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BOOK REVIEWS: Quantum Mechanics: Fundamentals
NASA Astrophysics Data System (ADS)
Whitaker, A.
2004-02-01
This review is of three books, all published by Springer, all on quantum theory at a level above introductory, but very different in content, style and intended audience. That of Gottfried and Yan is of exceptional interest, historical and otherwise. It is a second edition of Gottfried’s well-known book published by Benjamin in 1966. This was written as a text for a graduate quantum mechanics course, and has become one of the most used and respected accounts of quantum theory, at a level mathematically respectable but not rigorous. Quantum mechanics was already solidly established by 1966, but this second edition gives an indication of progress made and changes in perspective over the last thirty-five years, and also recognises the very substantial increase in knowledge of quantum theory obtained at the undergraduate level. Topics absent from the first edition but included in the second include the Feynman path integral, seen in 1966 as an imaginative but not very useful formulation of quantum theory. Feynman methods were given only a cursory mention by Gottfried. Their practical importance has now been fully recognised, and a substantial account of them is provided in the new book. Other new topics include semiclassical quantum mechanics, motion in a magnetic field, the S matrix and inelastic collisions, radiation and scattering of light, identical particle systems and the Dirac equation. A topic that was all but totally neglected in 1966, but which has flourished increasingly since, is that of the foundations of quantum theory. John Bell’s work of the mid-1960s has led to genuine theoretical and experimental achievement, which has facilitated the development of quantum optics and quantum information theory. Gottfried’s 1966 book played a modest part in this development. When Bell became increasingly irritated with the standard theoretical approach to quantum measurement, Viki Weisskopf repeatedly directed him to Gottfried’s book. Gottfried had devoted a chapter of his book to these matters, titled ‘The Measurement Process and the Statistical Interpretation of Quantum Mechanics’. Gottfried considered the von Neumann or Dirac ‘collapse of state-vector’ (or ‘reduction postulate’ or ‘projection postulate’) was unsatisfactory, as he argued that it led inevitably to the requirement to include ‘consciousness’ in the theory. He replaced this by a more mathematically and conceptually sophisticated treatment in which, following measurement, the density matrix of the correlated measured and measuring systems, rho, is replaced by hat rho, in which the interference terms from rho have been removed. rho represents a pure state, and hat rho a mixture, but Gottfried argued that they are ‘indistinguishable’, and that we may make our replacement, ‘safe in the knowledge that the error will never be found’. Now our combined state is represented as a mixture, it is intuitive, Gottfried argued, to interpret it in a probabilistic way, |cm|2 being the probability of obtaining the mth measurement result. Bell liked Gottfried’s treatment little more than the cruder ‘collapse’ idea of von Neumann, and when, shortly before Bell’s death, his polemical article ‘Against measurement’ was published in the August 1990 issue of Physics World (pages 33-40), his targets included, not only Landau and Lifshitz’s classic Quantum Mechanics, pilloried for its advocacy of old-fashioned collapse, and a paper by van Kampen in Physica, but also Gottfried’s approach. Bell regarded his replacement of rho by hat rho as a ‘butchering’ of the density matrix, and considered, in any case, that even the butchered density matrix should represent co-existence of different terms, not a set of probabilities. Gottfried has replied to Bell ( Physics World, October 1991, pages 34-40; Nature 405, 533-36 (2000)). He has also become a major commentator on Bell’s work, for example editing the section on quantum foundations in the World Scientific edition of Bell’s collected works. Thus it is exceedingly interesting to discover how he has responded to Bell’s criticisms in the new edition of the book. To commence with general discussion of the new book, the authors recognise that the graduate student of today almost certainly has substantial experience of wave mechanics, and is probably familiar with the Dirac formalism. The 1966 edition had what seems, at least in retrospect, a relatively soft opening covering the basic ideas of wave mechanics and a substantial number of applications; it did not reach the Dirac formalism in the first two hundred pages, though it then moved on to tackle rather advanced topics, including a very substantial section on symmetries, which tackled a range of sophisticated issues. The new edition has been almost entirely rewritten; even at the level of basic text, it is difficult to trace sentences or paragraphs that have moved unscathed from one edition to the next. As well as the new topics, many of the old ones are discussed in much greater depth, and the general organisation is entirely different. As compared with the steady rise in level of the 1966 edition, the level of this book is fairly consistent throughout, and from the perspective of a beginning graduate student, I would estimate, a little tough. A brief introductory chapter gives a useful, though not particularly straightforward, discussion of complementarity, uncertainty and superposition, and concludes with an informative though very short summary of the discovery of quantum mechanics, together with a few nice photographs of some of its founders. There follow two substantial chapters which are preparation for the later study of actual systems. The first, called ‘The Formal Framework’ is a fairly comprehensive survey of the methods of quantum theory---Hilbert space, Dirac notation, mixtures, the density matrix, entanglement, canonical quantization, equations of motion, symmetries, conservation laws, propagators, Green’s functions, semiclassical quantum mechanics. The level of mathematical rigour is stated as ‘typical of the bulk of theoretical physics literature---slovenly’; those unhappy with this are directed to the well-known books of Jordan and Thirring. The next chapter---‘Basic Tools’---explains a set of topics which students will need to use when studying particular systems---angular momentum and its addition, free particles, the two-body system, and the standard approximation techniques. There follow chapters on low-dimensional systems---harmonic oscillator, Aharanov--Bohm effect, one-dimensional scattering, WKB and so on; hydrogenic atoms---the Kepler problem, fine and hyperfine structure, Zeeman and Stark effects; and on two-electron atoms---spin and statistics. As in the first edition, there is a substantial treatment of symmetries, including time reversal, Galileo transformations, the rotation group, the Wigner-Eckart theorem and the Berry phase. There are two long chapters on scattering---elastic and inelastic respectively, including an account of the S matrix. The treatment of electrodynamics is much extended and modernised compared to that in the first edition. There are discussions of the quantization of the free field, causality and uncertainty in electrodynamics, vacuum fluctuations including the Casimir effect and the Lamb shift, and radiative transitions. There is a treatment of quantum optics, but this a only a brief introduction to a rapidly expanding subject, designed to facilitate understanding of the experiments on Bell’s inequalities discussed in the later chapter on interpretation. Other topics are the photoeffect in hydrogen, scattering of photons, resonant scattering and spontaneous decay. Identical particles are discussed, with a treatment of second quantization and an introduction to Bose--Einstein condensation, and the last chapter is a brief introduction to relativistic quantum mechanics, including the Dirac equation, the electromagnetic interaction of a Dirac particle, the scattering of ultra-relativistic electrons and a treatment of bound states in a Coulomb field. Gottfried and Yan’s response both to the growing interest in work on foundational matters in general, and to the specific criticism of Bell on the previous edition is included in the chapter entitled `Interpretation'. This chapter appears to be something of a hybrid. The first four sections broadly discuss hidden variables. An account of the Einstein--Podolsky--Rosen approach is followed by a general study of hidden variables, including a discussion of what the authors call the Bell--Kochen--Specker theorem. Bell’s theorem is analysed in some detail; also included are the Clauser--Horne inequality and the experimental test of the Bell inequality by Aspect. There is an interesting discussion of locality. Granted that both quantum mechanics and experiment (the latter admittedly with a remaining loophole) are in conflict with what the authors call a classical conception of locality as embodied in the Bell inequality, they ask whether quantum mechanics is actually non-local if one uses a definition of locality entailing no ingredients unknown to quantum mechanics. Their answer is that it is a matter of taste. In the statistical distribution of measurement outcomes on separate systems in entangled states, there is no hint of non-locality and no question of superluminal signalling. But quantum mechanics displays perfect correlations between distant outcomes, even though Bell’s theorem demonstrates that pre-existing values cannot be assumed. The second part of this chapter is a discussion of the measurement procedure similar to that in the first edition. The authors aim to show how measurement results are obtained and displayed, and how the appropriate probabilities are determined. The expression of this intention, however, is accompanied by the statement that they are not attempting to derive the statistical interpretation of quantum mechanics, which is assumed, but to examine whether it gives a consistent account of measurement. The conclusion is that after a measurement, interference terms are ‘effectively’ absent; the set of ‘one-to-one correlations between states of the apparatus and the object’ has the same form as that of everyday statistics and is thus a probability distribution. This probability distribution refers to potentialities, only one of which is actually realized in any one trial. Opinions may differ on whether their treatment is any less vulnerable to criticisms such as those of Bell. To sum up, Gottfried and Yan’s book contains a vast amount of knowledge and understanding. As well as explaining the way in which quantum theory works, it attempts to illuminate fundamental aspects of the theory. A typical example is the ‘fable’ elaborated in Gottfried’s article in Nature cited above, that if Newton were shown Maxwell’s equations and the Lorentz force law, he could deduce the meaning of E and B, but if Maxwell were shown Schrödinger’s equation, he could not deduce the meaning of Psi. For use with a well-constructed course (and, of course, this is the avowed purpose of the book; a useful range of problems is provided for each chapter), or for the relative expert getting to grips with particular aspects of the subject or aiming for a deeper understanding, the book is certainly ideal. It might be suggested, though, that, even compared to the first edition, the isolated learner might find the wide range of topics, and the very large number of mathematical and conceptual techniques, introduced in necessarily limited space, somewhat overwhelming. The second book under consideration, that of Schwabl, contains ‘Advanced’ elements of quantum theory; it is designed for a course following on from one for which Gottfried and Yan, or Schwabl’s own `Quantum Mechanics' might be recommended. It is the second edition in English, and is a translation of the third German edition. It has a restricted range of general topics, and consists of three parts entitled `Nonrelativistic Many-Particle Systems', `Relativistic Wave Equations', and `Relativistic Fields'. Thus it studies in some depth areas of physics which are either dealt with in an introductory fashion, or not reached at all, by Gottfried and Yan. Despite its more advanced level, this book may actually be the more accessible to an isolated learner, because the various aspects are developed in an unhurried fashion; the author remarks that ‘the inclusion of all mathematical steps and full presentation of intermediate calculations ensures ease of understanding’. Many useful student problems are included. The presentation is said to be rigorous, but again this is a book for the physicist rather than the mathematician. The treatment of many-particle systems begins with a rather general introduction to second quantization, and then applies this formalism to spin-1/2 fermions and bosons. The study of fermions includes consideration of the Fermi sphere, the electron gas, and the Hartree--Fock equations for atoms; that of bosons includes Bose--Einstein condensation, Bogoliubov theory of the weakly interacting Bose gas, and a brief account of superfluidity. The last section of this part of the book investigates in detail the dynamics of many-particle systems on a microscopic quantum-mechanical basis using, in particular, the dynamical correlation functions. In the second part which considers relativistic wave equations, the Klein--Gordon and Dirac equations are derived, and the Lorentz covariance of the Dirac equation is established. The role of angular momentum in relativistic quantum mechanics is explained, as a preliminary to the study of the energy levels in a Coulomb potential using both the Klein--Gordon and Dirac equations, the latter being solved exactly for the hydrogen atom. For larger atoms, the Foldy--Wouthuysen transformation is explained, and also relativistic corrections and the Lamb shift. There is an interesting chapter on the physical interpretation of the Dirac equation, including such topics as the negative energy solutions, the Zitterbewegung and the Klein paradox. The last chapter in this part of the book is an extensive treatment of the symmetries and other properties of the Dirac equation, including the behaviour under rotation, translation, reflection, charge conjugation and time reversal. Helicity is explained, and the behaviour of zero-mass fermions is discussed; even though it now seems certain that neutrinos do not have zero-mass, this treatment provides a good approximation to their behaviour if they have high enough momenta. The last section on relativistic fields contains chapters on the quantization of relativistic fields, the free Klein--Gordon and Dirac fields, quantization of the radiation field, interacting fields and quantum electrodynamics, including the S matrix, Wick’s theorem and Feynman diagrams. Schwabl’s book would be excellent for those requiring a detailed presentation of the topics it includes, at a level of rigour appropriate to the physicist. It includes a substantial number of interesting problems. The third book under consideration, that by Gustafson and Sigal is very different from the others. In academic level, at least the initial sections may actually be slightly lower; the book covers a one-term course taken by senior undergraduates or junior graduate students in mathematics or physics, and the initial chapters are on basic topics, such as the physical background, basic dynamics, observables and the uncertainty principle. However the level of mathematical sophistication is far higher than in the other books. While the mathematical prerequisites are modest---real and complex analysis, elementary differential equations and preferably Lebesgue integration, a third of the book is made up of what are called mathematical supplements---on operator adjoints, the Fourier transform, tensor products, the trace and trace class operators, the Trotter product formula, operator determinants, the calculus of variations (a substantial treatment in a full chapter), spectral projections, and the projecting-out procedure. On the basis of these supplements, the level of mathematical sophistication and difficulty is increased substantially in the middle section of the book, where the topics considered are many-particle systems, density matrices, positive temperatures, the Feynman path integral, and quasi-classical analysis, and there is a final substantial step for the concluding chapters on resonances, an introduction to quantum field theory, and quantum electrodynamics of non-relativistic particles. A supplementary chapter contains an interesting approach to the remormalization group due to Bach, Fröhlich and Sigal himself. This book is well-written, and the topics discussed have been well thought-out. It would provide a useful approach to quantum theory for the mathematician, and would also provide access for the physicist to some mathematically advanced methods and topics, but the physicist would definitely have to be prepared to work hard at the mathematics required.