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This unique reference book contains 372 articles selected from 762 plenary lectures, workshops and poster presentations made during the Thirteenth American Peptide Symposium held in Edmonton, Alberta, Canada. The book opens with Nobel Laureate Dr. Bruce Merrifield's `Remarks on Peptide Chemistry' which focus on past scientists and their contributions of peptide chemistry in all aspects of biology, and Dr. Victor Hruby's Pierce Award Lecture on designing peptides, pseudopeptides and peptidomimetics to understand the relationship between structure and biology activity. The contributions are grouped into 14 sections: Synthetic and Analytical Methods Peptide Mimetics Glycopeptides/Lipopeptides Peptide Hormones/Neuropeptides Peptide Inhibitors/Peptide-Receptor Interactions Peptide Vaccines and Immunology Conformational Analysis Peptide Pharmaceuticals/Diagnostics and Peptide Delivery Computational Biochemistry Peptide Macromolecular Interactions Peptide Libraries De novo Design of Peptides and Proteins; and three Workshops: Approaches and Advances in Peptide Synthesis, Purification and Analysis An Introduction to NMR Spectroscopy of Peptides An Introduction to Energy Minimization, Molecular Dynamics, Molecular Modelling and Conformational Analysis of Peptides. This 1200 page compendium of current research from both academic and industrial laboratories demonstrates the exponential growth of the use of peptides in the diverse fields of medical science.

Natural grasslands, pastures and meadows are among the vegetation types most frequently investigated with phytosociological methods. This was one of the reasons why volume 13, Application of vegetation science to grassland husbandry and agriculture, edited by W. Krause, appeared as one of the first volumes of this handbook. It appeared under the chief editorship of Prof. R. Tiixen and in his time main emphasis of the handbook was placed on Ziirich-Montpellier methods and the European vegetation. When we redesigned the handbook we felt the need to include other methods and aims of grassland analyses as well as a more global coverage of grasslands. Especially the natural dry and semidry areas of the world needed to be covered. was very fortunate in getting Prof. Tueller of the University of Reno I Nevada as an editor for this volume. He and the colleagues he motivated to compile volume 14 on Application of vegetation science to rangeland analysis and management have created a truly global coverage of the topics interesting for vegetation analyses in natural grasslands. Since volume 13 covered the problems of anthropogenically created grasslands, this topic was not expressly treated in order to avoid duplication. For the same reason no specific attempt was made to get more papers from Europe and the temperate forest region in general. The cooperation with Dr. Tueller has been very rewarding for me.

Until 1-1-1972 DINKHORST inserted 170 iridocapsular lenses in 158 patients. The first operation took place on 16-9--1965*. Initially, indication for the fitting of an iridocapsular lens was congenital or traumatic cataract in children, since the e~tracapsular cataract extraction necessary at that age, facilitated iridocapsular fixation (DINKHORST, 1967ac; DINKHORST & GODIN, 1967d, 1970b, 197lb, 1972d). After 1970 MANSCHOT's histopathological findings (see Chapter VIII) and the desire to reduce disloca­ tions and the development of ECD to a minimum induced DINKHORST to per­ form primary iridocapsular lens implant operations in cases with senile cataract as weH. This explains the decrease in the fitting or iris clip lens implants in favor ofiridocapsular lens implants (see Fig. 39). The distribution ofthe patients' ages in these 170 cases is, therefore, quite different from that of the 677 iris clip lens implant operations (see Fig. 40). The technique ofthe iridocapsular lens implantation is described on page 59. Numerical data are shown in Fig. 41. Noteworthy in this table are the following points: 1. The average age at operation of 30.82 years which is very low compared with the 65.80 years for the iris clip lens series, may be explained by the relatively !arge nurober of children in this series (see Fig. 40).

Under the title of Function Algebras we may now include a very large number of works. published mainly in the last decade, which consti­ tute one of the important chapters of functional analysis. This chapter has grown up from various problems. permanently furnished to mathe­ matics. by the theory of functions. using modern methods of algebra, topology and functional analysis and presenting large possibilities of applications in operators theory. Herefrom proceeds its living character, the variety of obtained results. the variety of forms and contexts in which these results can be found. This also explains the difficulty of an exhaustive exposition of these problems. The purpose of the monograph is to present a coherent exposition of the fundamental results of this theory with an orientation to their applicability to the theory of operator representations of function alge­ bras. The idea of such a work appeared during the seminaries on function algebras held at the Mathematical Institute in Bucharest. under the direc­ tion of C. Foia~ and at the Faculty of Mathematics and Mechanics under the direction of N. Boboc. It is a pleasure for the author to express his gratitude to C. Foia~ for assistance in his efforts. in general. and for the large contribution the discussions and cooperation with him had brought in the elaboration of this monograph. I also would like to thank N. Boboc for the clear discussions we have had during the seminaries and the elaboration of some chapters.

Proceedings of the 129th Symposium of the International Astronomical Union, held in Cambridge, MA, USA, May 10-15, 1987

The objective of this meeting was to bring together collea­ gues from different branches of observational astronomy and theoretical astrophysics to discuss and analyse the rapid progress in our knowledge and understanding of the matter surrounding stars, streaming off stellar surfaces, or fall­ ing onto stars. The meeting was sponsored by IAU Commis­ sions 36 (Theory of Stellar Atmospheres), 29 (Stellar Spec­ tra), and 34 (Interstellar Matter). There were two special reasons for organizing this meeting at Heidelberg in 1986: During this year the University of Heidelberg celebrated its 600th anniversary and the IAU symposium joined the many scientific events accompanying this celebration. Secondly, the year 1986 also marked the conclusion of a special co­ operative research project ("Sonderforschungsbereich") in astrophysics at Heidelberg, a major part of which had been devoted to the physics of circumstellar matter. The main topics discussed at this meeting were: (1) circumstellar matter, bipolar flows, and jets from young stars and protostars; (2) circumstellar envelopes of evolved stars; (3) stellar coronae; (4) stellar winds from hot and cool stars; (5) dust formation and circumstellar chemistry. Many exciting new results were presented in 21 invited or review papers, 26 contributed papers, and 127 poster papers. This symposium would not have been possible without the generous financial assistance of the International Astronomical Union, the German Science Foundation (DFG), and the State Government of Baden-Wurttemberg. The practi­ cal support of the University of Heidelberq and the Max­ Planck-Society was also very valuable.

As a star, the sun is continuously emitting an enormous amount of energy 33 into space, up to as much as 3. 9 X 10 erg/ s. This energy emission consists of three modes. Almost all the energy is emitted in the form of the familiar black-body radiation, commonly called sunlight. Although the amount of energy emitted is small, the sun also emits x rays, extreme ultraviolet (EUV), and UV radiations, which are absorbed above the earth's stratosphere. These constitute the second mode of solar energy, separate from the black-body radiation that penetrates the lower layers of the atmosphere. The sun has another important mode of energy emission in which the energy is carried out by charged particles. These particles have a very wide range of energies, from less than I keY to more than I GeV. Because of this wide range, it is convenient to group them into two components: particles with energies greater than 10 keY and the lower-energy particles. The former are generally referred to as solar protons or solar cosmic rays; their emission is associated with active features on the sun. Their interaction with the atmosphere is similar to that of the x ray and EUV radiation. Low-energy particles constitute plasma, a gas of equal numbers of positive and negative particles. Actually, this plasma is the outermost part of the solar atmosphere, namely the corona, which blows out continuously . For this reason, the plasma flow is called the solar wind.

Approach your problems from the right end It isn't that they can't see the solution. It is and begin with the answers. Then one day, that they can't see the problem. perhaps you will find the final question. G. K. Chesterton. The Scandal of Father 'The Hermit Clad in Crane Feathers' in R. Brown 'The point of a Pin', van Gu!ik. 'g The Chinese Maze Murders. Growing specialization and diversification have brought a host of monographs and textbooks on increasingly specialized topics. However, the "tree" of knowledge of mathematics and related fields does not grow only by putting forth new branches. It also happens, quite often in fact, that branches which were thought to be completely disparate are suddenly seen to be related. Further, the kind and level of sophistication of mathematics applied in various sciences has changed drastically in recent years: measure theory is used (non-trivially) in regional and theoretical economics; algebraic geometry interacts with physics; the Minkowsky lemma. coding theory and the structure of water meet one another in packing and covering theory; quantum fields, crystal defects and mathematical programming profit from homotopy theory; Lie algebras are relevant to filtering; and prediction and electrical engineering can use Stein spaces. And in addition to this there are such new emerging subdisciplines as "experimental mathematics", "CFD", "completely integrable systems", "chaos, synergetics and large-scale order", which are almost impossible to fit into the existing classification schemes. They draw upon widely different sections of mathematics.

Growing specialization and diversification have brought a hor'st of monographs and textbooks on increasingly specialized topics. However, the "tree" of knowledge of mathematics and related fields does not grow only by putting forth new branches. It also happens, quite often in fact, that branches which were thought to be completely disparate are sudden­ ly seen to be related. Further, the kind and level of sophistication of mathematics applied invarious sciences has changed drastically in recent years: measure theory is used (non-trivially) in regional and theoretical economics; algebraic geometry interacts with physics; the Minkowsky lemma, coding theory and the structure of water meet one another in packing and covering theory; quantum fields, crystal defects and mathematical programming profit from homotopy theory; Lie algebras are relevant to filtering; and prediction and electrical engineering can use Stein spaces. And in addition to this there are such new emerging subdisciplines as "completely integrable systems", "chaos, synergetics and large-scale order", which are almost impossible to fit into the existing classification schemes. They draw upon widely different sections of mathematics. This programme, Mathematics and Its Applications, is devoted to such (new) interrelations as exempli gratia: - a central concept which plays an important role in several different mathematical andjor scientific specialized areas; - new applications of the results and ideas from one area of scien­ tific endeavor into another; - influences which the results, problems and concepts of one field of enquiry have and have had on the development of another.

Ken Freeman I would like to pick out a few items that I found particularly interesting. The choice probably reflects my ignorance, because many of these topics are no doubt more known to most of you. I am fairly sure that some of them are basic and important. We will start with the first session. There were three closely related papers on the evolution of massive stars, the formation of open clusters and associations and the IMF. We learned that clusters appear to form in initially bound clouds 6 of masses between 10'+_10 M , but star formation is a destructive process. Most of the gas is@ lost and the remaining stars then find themselves in an unbound system, which naturally disperses on a dynamical time. As a result of this, star formation is typically a fairly inefficient process, at least on the scale of open clusters. However (as Heggie pointed out) it seems to be somewhat more efficient on smaller scales, as evidenced by the fairly high incidence of binary stars. To form a bound cluster requires a higher efficiency of star formation, typically 30% or more, and we see how the three papers of this morning session relate: the initial mass function and the timing of where and when the DB stars form dictate the likely fate of the system.

The XVlllth General Assembly of the International Astronomical Union was held in Patras, Greece, from 17-26 August 1982. It was marked by the tragic death of the President of the IAU, Professor M.K.V. Bappu, on August 19, 1982. This sad event, without precedent in the history of the Union, posed serious problems to the organization of the General Assembly, which could only be overcome by the full collaboration of all members, the organizers, and the Executive Committee. A tribute to the memory of Prof. Bappu was paid during a plenary meeting on 23 August 1982. The full texts of the speeches are published in Chapter I of this . volume. The excellent scientific programme in Patras was organized by the Presidents of the 40 IAU Commissions and coordinated by the IAU General Secretary (1979-1982), Professor P.A. Wayman. The local arrangements were taken care of by Professor C. Goudas and his collaborators from the Patras University. Due to the unexpected withdrawal in 1979 of another invitation to host the 1982 IAU General Assembly, the organizers in Greece had less than two years available for the extensive preparations, and our hearty thanks are due to them for their persistent efforts, which made this General Assembly an outstanding success.

The thermodynamics of the atmosphere is the subject of severai chapters in most textbooks on dynamic meteorology, but there is no work in English to give the subject a specific and more extensive treatment. In writing the present textbook, we have tried to fiII this rather remarkable gap in the literature related to atmospheric sciences. Our aim has been to provide students of meteorology with a book that can play a role similar to the textbooks on chemical thermodynamics for the chemists. This implies a previous knowledge of general thermodynamics, such as students acquire in general physics courses; therefore, although the basic principles are reviewed (in the urst four chapters), they are only briefly discussed, and emphasis is laid on those topics that wilI be useful in later chapters, through their application to atmospheric problems. No attempt has been made to introduce the thermodynamics ofirreversible processes; on the other hand, consideration of heterogeneous and open homogeneous systems permits a rigorous formulation of the thermodynamic functions of c10uds (exclusive of any consideration of microphysical effects) and a better understanding of the approx- imations usually implicit in practical applications.

For over 35 years, radio astronomical techniques have made an impressive series of advances in our understanding of solar phenomena. However, although the subject has been partially discussed in "Paris Symposium on Radio Astronomy" in 1958, NASA-GSFC Symposium on "Physics of Solar Flares" in 1963, and the lAU Symposium No. 57 on "Coronal Disturbances" in 1973, there has not been a major international meeting dedicated to "Radio Physics of the Sun". This is the first major symposium on the subject held under the auspices of the International Astronomical Union. It was jointly spon­ sored by lAU Commission 40, Radio Astronomy, and by lAU Commission 10, Solar Activity. It was also sponsored by the Solar Physics Division of the American Astronomical Society. Thig volume contains the proceedings of this meeting, lAU Symposium No. 86 on "Radio Physics of the Sun" that was held in College Park, Maryland, August 7-10, 1979. The Scientific Organizing Committee of the Symposium consisted of M. R. Kundu (chairman), G. A. Dulk, O. Hachenberg, M. Kuperus, D. J. McLean, D. Melrose, M. Pick, J. L. Steinberg, T. Takakura, A. Tlamicha and V. V. Zheleznyakov. The topics and speakers were chosen in order to emphasize the current observational material with particular reference to centi­ meter wavelength observations of a few arc-second resolution, fast two-dimensional pictures of the sun at meter-decameter wavelengths and the recent advances in plasma and radiation theory.

The lAU Symposium No. 78, "Nutation and the Earth's Rotation," was held in Y~ev, USSR, from 23 to 28 May, 1977. The Organizing Committee included E. P. Fedorov and R. O. Vicente (Joint Chairmen), W. Fricke, J. Kovalevsky, P. Melchior, N. Pariisky, M. Rochester, C. Sugawa, G. Wilkins and Ya. Yatskiv, who presided over the Local Organizing Com­ mittee. The meeting was sponsored by Commission 19 and co-sponsored by Commissions 4, 8, and 31. There were 114 registered participants from 14 countries. The main topics covered were as follows: the specification of nutation in the lAU system of astronomical constants; determination of forced nutation and nearly diurnal free polar motion from astronomical observations; expected use of lunar ranging data and long baseline interferometers for precise measurement of the nutation terms; models of the internal constitution of the Earth as the basis of a new theory of nutation; the effect of the ocean and liquid core on the rotation of the Earth; and the interaction between Earth tides and nutation.

The aim of this paper is to show that the theory of jet bundles supplies the appropriate setting for the study of Backlund trans­ formations. These transformations are used to solve certain partial differential equations, particularly non-linear evolution equations. Of course jets have been employed for some time in the theory of partial differential equations, but so far little use has been made of them in applications. In the meanwhile, substantial progress has been made in the study of non-linear evolution equations. This work has been encouraged by the dis­ covery of remarkable properties of some such equations, for example the existence of soliton solutions and of infinite se­ quences of conservation laws. Among the techniques devised to deal with these equations are the inverse scattering method and the Backlund transformation. In our opinion the jet bundle formulation offers a unifying geometrical framework for under­ standing the properties of non-linear evolution equations and the techniques used to deal with them, although we do not consider all of these properties and techniques here. The relevance of the theory of jet bundles lS that it legitimates the practice of regarding the partial derivatives of field variables as independent quantities. Since Backlund trans­ formations require from the outset manipulation of these partial derivatives, and repeated shifts of point of view about which variables are dependent on which, this geometrical setting clari­ fies and simplifies the concepts involved, and offers the prospect of bringing coherence to a variety of disparate results.

Very few people have contributed as much to twentieth-century physics as Julian Schwinger. It is therefore appropriate to offer a retrospective of his work on the occasion of his sixtieth birthday (February 12, 1978). We hope, in offering this selection of his papers, to bring to light ideas and results that may have been partly overlooked at the time of the original publication. Schwinger has published prodigiously on a great variety of subjects, as is evident from the comprehensive list of publications arranged in chronological order which appears on p. xiii. Needless to say, only a small subset could be included in the present modest volume. In the selection, great weight was assigned to papers that seem to be less widely known or appreciated than they deserve. Many important papers are therefore omitted. (Examples: Paper [64] 'On Gauge Invariance and Vacuum Polarization' and Paper [69] 'On Angular Momentum', both of which have been reprinted elsewhere. ) The collection is a personal one, having been chosen by Schwinger himself, and is therefore of particular interest. It would probably not be interesting to offer an analysis, by the editors, of Schwinger's contributions to physics. However, we are very pleased to be able to include Schwinger's own informal and very personal comments about each article that appears in this volume. These comments indicate his reasons for choosing these particular articles and, in many cases, provide a capsule synopsis of what he considers most valuable.