The 6th Advanced Course in Theoretical Physics was held at the University of Cape Town, January 8-19, 1990. The topic of the course was "Phase Structure of Strongly Interacting Matter." There were ten invited speakers from overseas, each having up to six hours in which to present his field of research to a relatively small audience of about 50 participants. This allowed for the presentation of a broad, coherent and pedagogical review of the present status of the field. In addition there were several one-hour presentations by local participants. The main emphasis of the course was on the study of the properties of high density hot nuclear matter. This field is of particular interest because of the belief that a deconfined quark-gluon plasma could be created in such an environment when the temperature reaches about 200MeV. In the nuclear regime a so-called "liquid-to-gas" phase transition is expected at a temperature of approximately 10- 20MeV. Both of these topics received ample attention at the school. Owing the nature of the field, there exists much overlapping interest from both the nuclear physics and high-energy particle physics communities. It is hoped that these proceedings will contribute to building a bridge between the two groups."

Recombination lines at radio wavelengths have been - and still are - a pow erful tool for modern astronomy. For more than thirty years they have allowed astronomers to probe the gases from which stars form. They have even been detected in the Sun. In addition, observations of these spectral lines facilitate basic research into the atom, in forms and environments that can only exist in the huge dimensions and extreme conditions of cosmic laboratories. We intend this book to serve as a tourist's guide to the world of Radio Recombination Lines. It contains three divisions: a history of their discovery, the physics of how they form and how their voyage to us influences their spectral profiles, and a description of their many astronomical contributions to date. The appendix includes supplementary calculations that may be useful to some astronomers. This material also includes tables of line frequencies from 12 MHz to 30THz (AlOJLm) as well as FORTRAN computer code to calculate the fine structure components of the lines, to evaluate radial matrix integrals, and to calculate the departure coefficients of hydrogen in a cosmic environment. It also describes how to convert observational to astrophysical units. The text includes extensive references to the literature to assist readers who want more details.

Proceedings of the International Conference, Antwerp, Belgium, September 6-10, 1982

In recent years there has been growing interest in the nucleon-nucleon correl ations inside nuclei. In many respects the motions of the nucleons can be very well described by an overall mean field, so that the motion of each nucleon is governed by the mean field due to all the other nucleons. This concept underlies the Fermi-gas, Hartree-Fock and shell models and has enabled a range of nuclear properties to be calculated, often to surprising accuracy. It gradually became clear, however, that these mean-field models are limited by the effects due to the very strong interactions between the nucleons that occur at short distances; these are the short-range correlations. They are responsible for instance for the high-momentum components in the nucleon momentum dis tribution, and prevent the simultaneous description of the nuclear density and momentum distributions by the same mean field. It thus becomes necessary to develop methods for including the effects of nucleon correlations in nuclei, and these are the main subject of this book. Some related problems of nuclear structure were discussed in an earlier book by the same authors: Nucleon Momentum and Density Distributions in Nuclei (Clarendon Press, Oxford, 1988). The main aim of that book was to study the effects of nucleon-nucleon correlations, both short-range and tensor, on the nucleon momentum distribution, which is particularly sensitive to these correl ations, and on the nucleon density distribution."

Hydrogen can behave as an alkaline metal or a halogen and can react with nearly all elements of the periodic table. This explains the large number of metal hydrides. Since T. Graham's first observation of the absorption of hydrogen in palladium in 1866 the behaviour of hydrogen in metals has been studied very extensively. The interest was motivated by the possible application of metal-hydrogen systems in new technologies (e.g., moderator material in nuclear fission reactors, reversible storage material for thermal energy and large amounts of hydrogen) and by the fact that metal hydrides show very exciting physical properties (e.g., superconductivity, quantum diffusion, order-disorder transitions, phase diagrams, etc.). Many of these properties have been determined for the stable hydrogen isotopes Hand D in various metals. In comparison, very little is known about the behaviour of the ra dioactive isotope tritium in metals. This book is a first attempt to summarize part of the knowledge of tritium gained in the last few years. In addition to the task of presenting the properties of tritium in metals, I have tried to compare these data with those of protium and deuterium. Furthermore, helium-3 is connected inse parably with tritium via the tritium decay. Therefore one chapter of this book is solely devoted to the curious properties of helium in metals caused mainly by its negligible solubility."

Marcos Moshinsky was born on 20 April 1921, in Kiev, Ukraine, and em- igrated to Mexico at the age of four. He began work at the Universidad N acional Aut6noma de Mexico on 1 January 1942, as a laboratory assis- tant working on the measurement of cosmic rays. He pursued his graduate studies at Princeton University, and wrote his thesis under the supervision of Professor Eugene Wigner. Since 1949, and in spite of many visits and temporary posts held abroad, Moshinsky has been based in Mexico. Through example and encouragement, Moshinsky may be credited to a large extent with the shaping of Mexican scientific research. He has di- rected 40 B. Sc. , M. Sc. , and Ph. D. theses, and published over 200 scientific articles and four books; he holds all the Mexican science prizes, and sev- eral international ones, being a member of 11 academies of learning. Talent and circumstance have placed Marcos Moshinsky at the origin of several of the enterprises of the Mexican and Latin American scientific communities: he was founding editor of the Revista Mexicana de F{sica from 1952 to 1967; the Escuela Latinoamericana de Fisica was initiated and five times organized by him in Mexico; he was founding member and later president of the Academia de la Investigaci6n Cientifica (1962-1963), the Sociedad Mexicana de Fisica (1967-1969), and the Centro Internacional de Fisica y Matematicas A plicadas (1986-), in Cuernavaca.

This book is the work of three specialists from the field of Economics (B.F), Business (S.S.) and the Natural Sciences (W.S.). While each chapter concentrates more or less on one or other of these areas, with varying degrees of complexity, it is hoped that the readers whatever their background will fmd something of value in each section, in particular those outside their own disciplines. The authors believe that such cross fertilization of ideas will become increasingly needed in the coming development of a sustainable growth society and it is therefore their hope that this book, as a first example of its kind, will thereby contribute in an interdisciplinary way to the general understanding of the issues of sustainable growth. The authors divided their main contributions to the book as follows: Bruno Fritsch Chapters 1,2,3,4,5 and 8 Stephan Schmidheiny Chapter 7 Walter Seifritz Chapters 2, 3, 4 and 6 They would like to thank in particular Lloyd Timberlake for his editorial advice and his assistance on chapter 7. Special thanks are due to Irena Kusar for preparing the original figures and diagrams and to the Paul Scherrer Institute for permission to use the illustration, printing and copying facilities during preparation of the manuscript. They would also like to thank Richard Stratton for assembling, typing and correcting the text, editing and final layout and for his helpful advice and contributions to organising the presentation of the material.

There are many kinds of nuc1ear data books; however some are too much specialized, while others have an arrangement of information which is inconvenient for students to use. With this book, we want to amend these situations. Handbooks of natural sciences must be exact and fair in their presentation of materials and they must be logical and convenient to use. If the users can develop new ideas or gain new insights from the books, they can be judged as valuable. The role of handbooks is not only to give a systematic representation of past knowledge, but also to serve as a basis for intellectual activity leading to future development. The purpose of this data book arises from the points described above. The chart of the nuc1ides which is frequently consulted by radioisotope users is not always convenient. By comparison, our Periodic Table with Nuc1ides has been devised with this in mind. It has been our experience that properties of a desired nuclide could be found in a much shorter time in the Periodic Table with Nuc1ides than in other nuc1ide charts. Additionally, by placing the -stabi1ity line within the nuc1ides in the table, the users may derive unam biguous ideas on the stability of the nuc1ides and the paths related to the creation of stable elements in the universe."

Atoms in strong radiation fields are interesting objects for study, and the research field that concerns itself with this study is a comparatively young one. For a long period after the ~scovery of the photoelectric effect. it was not possible to generate electro magnetic fields that did more than perturb the atom only slightly, and (first-or~er) perturbation theory could perfectly explain what was going on at those low intensities. The development of the pulsed laser bas changed this state of affairs in a rather dramatic way, and fields can be applied that really have a large, or even dominant influence on atomic structure. In the latter case, w~ speak of super-intense fields. Since the interaction between atoms and electromagnetic waves is characterized by many parameters other than the light intensity, such as frequency, iQnization potential, orbit time, etc., it is actually quite difficult to define what is exactly meant by the term 'super-intense'. Obviously the term does not have an absolute meaning, and intensity should always be viewed in relation to other properties of the system. An atom in a radiation field can thus best be described in terms of various ratios of the quantities involved. The nature of the system sometimes drastically changes if the value of one of these parameters exceeds a certain critical value, and the new regime could be called super-intense with respect to that parameter.

1. INTRODUCTION 2 2. CRAYONS COMBUSTIBLES 4 3. CLASSIFICATION DES DETAILS VUS PAR NEUTRONOGRAPHIE 8 4. REPERAGE DES NEUTRONOGRAMMES 12 5. UTILISATION DU RECUEIL 14 6. CONTENU DU RECUEIL 16 7. TERMINOLOGIE 30 8. INSTALLATIONS DE NEUTRONOGRAPHIE A L'INTERIEUR DE LA COMMUNAUTE EUROPEENNE 42 9. REFERENCES 54 10. COLLECTION DES NEUTRONOGRAMMES SUR PAPIER PHOTOGRAPHIQUE (ECHELLE 2:1) ET FILM (ECHELLE 1:1) 55 TABLE OF CONTENTS PREFACE 1. INTRODUCTION 3 2. FUEL PINS 5 3. CLASSIFICATION OF NEUTRON RADIOGRAPHIC FINDINGS 9 4. MARKING OF THE RADIOGRAPHS 13 5. HOW TO USE THE COLLECTION 15 6. CONTENTS OF THE COLLECTION 17 7. TERMINOLOGY 31 8. NEUTRON RADIOGRAPHY INSTALLATIONS IN THE EUROPEAN COMMUNITY 43 9. REFERENCES 54 10. REFERENCE NEUTRON RADIOGRAPHS ON PHOTOGRAPHIC PAPER (SCALE 2:1) AND FILM (SCALE 1:1) 55 PREFACE Although the principles of radiography with neutron beams have been known for some 45 years, their practical application in industry and research is still a rather young field. Norms, standards, and common terms of reference are scarce. One of the main tasks of the Neutron Radiography Working Group (NRWG) -constituted by the Joint Research Centre Petten of the Commission of the European Communities and national nuclear research centres within the European Community -has been to fill this gap.

The 7th International Workshop in the series LASER INTERACTION AND RELATED PLASMA PHENOMENA continued the high standards established by the earlier meetings in this series. It was organized under the directorship of Heinrich Hora and George H. Miley at the Naval Postgraduate School in Monterey, California, with Fred Schwirzke as the local organizer. These workshops have presented many "firsts" in laser plasma interactions and especially in laser fusion. Some presentations provided continuity with the past, most represented advancements; however, in some workshops, progress did not appear to be occurring as rapidly as in others. Therefore, it was a special pleasure that in the present workshop when, on October 30, 1985, Chiyoe Yamanaka disclosed a breakthrough in the generation of fusion neutrons with laser fusion targets. The 7th Workshop also continued to represent other new fields of laser-plasma interaction. The progress reported was most pronounced in the fields of X-ray lasers, laser acceleration of particles by electrostatic double layers in plasmas, and a particle beam technique to solve the geometric problem of muon-catalyzed fusion. The development of laser-plasma interactions at medium to high laser intensities may be seen in its whole complexity from a brief review of prior conferences. At the first Workshop in 1969, a comprehensive review of the field was presented by the speakers with the opening address by N.

The sixteenth European Conference on Few Body Problems in Physics has taken place from June 1 to June 6, 1998, in Autrans, a little village in the mountains, close to Grenoble. The Conference follows those organized in Peniscola (1995), Amsterdam (1993), Elba (1991), Uzhgorod (1990) ... The present one has been organized by a group of physicists working in different fields at the University Joseph Fourier of Grenoble who find in this occasion a good opportunity to join their efforts. The core of the organizing committee was nevertheless located at the Institut des Sciences Nucleaires, whose physicists, especially in the group of theoretical physics, have a long tradition in the domain. The Few Body Conference has a natural tendency to be a theoretical one - the exchange about the methods used in different fields is the common point to most participants. It also has a tendency to be a hadronic physics one - the corresponding physics community, perhaps due to the existence of experimen tal facilities devoted to the study of few body systems, is better organized. In preparing the scientific program, we largely relied on the advices of the Inter national Advisory Committee, while avoiding to follow these trends too closely."

This volume contains the proceedings ofthe NATO Advanced Research Workshop 950443 on "Gas lasers-recent development and future prospects". The workshop was held in Moscow, July 2-5, 1995. During the workshop 22 oral presentations and 23 posters havebeen presented. Among the continuously expanding research on new laser systems in the extending spectrum range gas lasers are unique in many ways: the availability of high (average) power in all parts of the spectrum from the far infrared to the vacuum ultraviolet, the homogeneity ofthe active medium with the potential ofhigh beam quality even at high power and their relatively low costs. In the gas laser development one can distinguish the research towards new or improved laboratory devices and the efforts that are devoted to the development of characteristics like reliability, low costs and versatility that make the laser more suitable for industrial purposes. The industrial applications with dedicated devices are not only a natural e"1ension ofthe laser development itselfbut moreover they have nowadays a strong stimulating effecton this development. The workshop offered the participants many opportunities to discuss fundamental and technological problems of different types of lasers connected with beam proporties, excitation technology, new pumping schemes, pulsed power, construction materials and new codes for the description of laser operation. The interest was especially directed towards high power systems operating in the ultraviolet and vacuum ultraviolet, the radio'frequency discharge physics for waveguide structures and the achievement in molecular CO and CO systems.

This book of proceedings collects the papers presented at the Workshop on Diagnostics for ITER, held at Villa Monastero, Varenna (Italy), from August 28 to September 1, 1995. The Workshop was organised by the International School of Plasma Physics "Piero Caldirola. " Established in 1971, the ISPP has organised over fifty advanced courses and workshops on topics mainly related to plasma physics. In particular, courses and workshops on plasma diagnostics (previously held in 1975, 1978, 1982, 1986, and 1991) can be considered milestones in the history of this institution. Looking back at the proceedings of the previous meetings in Varenna, one can appreciate the rapid progress in the field of plasma diagnostics over the past 20 years. The 1995 workshop was co-organised by the Istituto di Fisica del Plasma of the National Research Council (CNR). In contrast to previous Varenna meetings on diagnostics, which have covered diagnostics in present-day tokamaks and which have had a substantial tutorial component, the 1995 workshop concentrated specifically on the problems and challenges of ITER diagnostics. ITER (the International Thennonuclear Experimental Reactor, a joint venture of Europe, Japan, Russia, and the United States, presently under design) will need to measure a wide range of plasma parameters in order to reach and sustain high levels of fusion power. A list of the measurement requirements together with the parameter ranges, target measurement resolutions, and accuracies provides the starting point for selecting a list of candidate diagnostic systems.

Julian Schwinger had plans to write a textbook on quantum mechanics since the 1950s when he was teaching the subject at Harvard University regularly. * t Roger Newton remembers: A] group of us (Stanley Deser, Dick Arnowitt, Chuck Zemach, Paul Martin and I forgot who else) wrote up lecture notes on his Quantum Mechanics course but he never wanted them published because he "had not yet found the perfect way to do quantum mechanics. " The only text of those days that got published eventually - following a sug gestion by, and with the help of, Robert Kohler: : - were the notes to the lectures that Schwinger presented at Les Houches in 1955. The book was reissued in 1991, with this Special Preface by Schwinger 3]: The first two chapters of this book are devoted to Quantum Kine matics. In 1985 I had the opportunity to review that development in connection with the celebration of the 100th anniversary of Hermann Weyl's birthday. . . . ] In presenting my lecture 4] I felt the need to alter only one thing: the notation. Lest one think this rather triv ial, recall that the ultimate abandonment, early in the 19th century, of Newton's method of fluxions in favor of the Leibnizian calculus, stemmed from the greater flexibility of the latter's notation."

A fundamental question in contemporary astrophysics is the origin of the elements. Cosmochemistry seeks to answer when, how and where the chemical elements arose. Quantitative answers to these fundamental questions require a multi-disciplinary approach involving stellar evolution, explosive nucleosynthesis and nuclear reactions in different astrophysical environments. There remain, however, many outstanding problems and cosmochemistry remains a fertile area of research. This book is among the first in recent times to put together the essentials of cosmochemistry, combining contributions from leading astrophysicists in the field. The chapters have been organized to provide a clear description of the fundamentals, an introduction to modern techniques such as computational modelling, and glimpses of outstanding issues.

The Thirteenth European Conference on Few-Body Problems in Phys- ics (European Few-Body Problems XIII) was held at the Elba Internation- al Physics Centre (EIPC) in Marciana Marina, Isola d'Elba, Italy, during September 9-14, 1991. The previous Conferences of the series, promoted by the European Few-Body Physics Research Committee, took place in Budapest (1972), Graz (1973), Tiibingen (1975), Vlieland (1976), Uppsala (1977), Dubna (1979), Sesimbra (1980), Ferrara (1981), Tbilisi (1984), Bala- tonfiired (1985), Fontevraud (1987), and Uzhgorod (1990). The European Few-Body Conferences represent a relevant opportunity for European scientists interested in few-body problems, of summarizing and updating, together with colleagues from countries all over the world, the status of art in this field of research, which ranges from the study of atomic and molecular structure, to nuclear and particle physics. The suc- cess of this series of Conferences, which also represent a bridge between the triennial IUPAP International Conferences on Few-Body Problems in Physics, testifies the relevance reached by few-body physics in various fields and the important theoretical and experimental contributions pro- vided by the European few-body community.

This volume contains the Proceedings of the "XXIV. Inter nationale Universitatswochen fur Kernphysik" held in Schlad ming, Austria, in February 1985. It consists of the written versions of the lectures (3-4 hours) given at this winter school and includes also most of the seminars (30-50 minutes) presented. In choosing the topic for the 1985 meeting, our aim was to give an account of the present understanding of the nucleon-nucleon as well as nucleon-antinucleon inter actions. This field, which is of definite relevance in nuclear and particle physics, has witnessed a rapid develop ment in recent times both in theory and experiment. New evidence has emerged in the whole range from low to extremely high energies. It was an exciting experience to bring to gether knowledge from the very domains of nuclear and high energy physics as well as to meet the respective researchers. Thanks to the efforts of the lecturers, who did a splendid job in presenting the lectures and in preparing their lecture notes, a comprehensive insight into the hadronic interaction between nucleons and anti-nucleons was achieved. The lecture notes were reconsidered by the authors after the meeting and are now being published in their final form. The seminars mainly dealt with specific topics currently under investiga tion within this rather wide field. We are grateful to all authors for their efforts, as they made it possible to speed up the publication of these proceedings."

"I.E. Tamm" is one of the great figures of 20th century physics and the mentor of the late A.D. Sakharov. Together with I.M. Frank, he received the Nobel Prize in 1958 for the explanation of the Cherenkov effect. This book contains a commented selection of his most important contributions to the physical literature and essays on his contemporaries - Mandelstam, Einstein, Landau, and Bohr - as well as his contributions to Pugwash conferences. About a third of the selections originally appeared in Russian and are, to our knowledge, for the first time now available to Western readers. This volume includes a preface by Sir Rudolf Peierls, a biography compiled by Tamm's former students, V.Ya. Frenkel and B.M. Bolotovskii, and a complete bibliography.

Eugene Wigner is one of the very few scientists that may safely be describedas creators of 20th-century physics. This volume of his Collected Works is devoted to his contributions to nuclear energy. In his Introduction and Annotations A.M. Weinberg surveys Wigner's contributions to nuclear-reaction physics and nuclear engineering, at the same time giving a glimpse of the early history of nuclear-reactor technology. Wigner himself gave a lively and critical account, which is published in this volume for the first time. Furthermore the book contains forty-two reports and memoranda from 1941 to 1945 and twelve of Wigner's many patents relating to nuclear energy.

Fuzzy systems and soft computing are new computing techniques that are tolerant to imprecision, uncertainty and partial truths. Applications of these techniques in nuclear engineering present a tremendous challenge due to its strict nuclear safety regulation. The fields of nuclear engineering, fuzzy systems and soft computing have nevertheless matured considerably during the last decade. This book presents new application potentials for Fuzzy Systems and Soft Computing in Nuclear Engineering. The root of this book can be traced back to the series of the first, second and third international workshops on Fuzzy Logic and Intelligent Technologies in Nuclear Science (FUNS), which were successfully held in Mol, September 14-16, 1994 (FLINS'94), in Mol, September 25-27, 1996 (FLINS'96), and in Antwerp, September 14-16, 1998 (FLINS'98). The conferences were organised by the Belgian Nuclear Research Centre (SCKeCEN) and aimed at bringing together scientists, researchers, and engineers from academia and industry, at introducing the principles of fuzzy logic, neural networks, genetic algorithms and other soft computing methodologies, to the field of nuclear engineering, and at applying these techniques to complex problem solving within nuclear industry and related research fields. This book, as its title suggests, consists of nuclear engineering applications of fuzzy systems (Chapters 1-10) and soft computing (Chapters 11-21). Nine pertinent chapters are based on the extended version of papers at FLINS'98 and the other 12 chapters are original contributions with up-to-date coverage of fuzzy and soft computing applications by leading researchers written exclusively for this book."

An accelerator complex which gives extremely high-intensity proton beams is being constructed in Tokai, Japan. The project is operated by JAEA (Japan Atomic Energy Agency) and KEK (High Energy Accelerator Research Or- nization) and called J-PARC (Japan Proton Accelerator Research Complex). J-PARC accelerator complex consists of 200MeV linac, 3GeV rapid cycling synchrotron, and 30GeV main synchrotron. The energy of linac will be - tendedto400MeVandtheenergyofthemainringwillbeincreasedto50GeV in the near future. J-PARCaimstoperformvariousresearchesoflifeandmaterialsciencesby using neutron beams from the 3GeV rapid cycling synchrotron. J-PARC also aims to perform various particle and nuclear physics experiments by using the 50GeV main synchrotron. In this book we collected several proposals of particle and nuclear physics experiments to be performed by using 50GeV main synchrotron. Prof. Nagamiya gives a brief introduction of J-PARC. He describes the purpose of the project, the aims of the various facilities, and the researches to be done by using these facilities. Prof. Ichikawa discusses about the long baseline nutrino oscillation expe- ment. This proposal is called T2K (Tokai to Kamioka) and it aims to measure mixinganglesintheleptonsector.Theytrytoperformaprecisemeasurement of ? by measuring the ? disappearance. Then they go to determine ? by 23 ? 13 measuring ? -? appearance signal. They also search for sterile components ? e by measuring NC events. Prof. Lim discusses about the experiment which searches a very rare decay 0 0 oftheneutralkaon:K ? ? ?? -.ThisdecayoccursviaadirectCPviolation. L Hewillsearchthisdecaymodewithhighersensitivitythanthestandardmodel expectation level.

Why to apply solid-state NMR? - By now, we should have learned that NMR is mainly used for the study of molecules in solution, while x-ray diffraction is the method of choice for solids. Based on this fact, the two recent 'NMR-Nobelprizes' went indeed into the liquid phase: my own one eleven years ago, and particularly the most recent one to Kurt Wuthrich. His prize is beyond any doubts very well justified. His contribution towards the study of biomolecules in solution, in their native (or almost native) environment is truly monumental. We all will profit from it indirectly when one of our future diseases will be cured with better drugs, based on the insightful knowledge gained through liquid-state NMR. Two fields of NMR are still left out of the Nobel Prize game: magnetic reso nance imaging (MRI) and solid-state NMR. The disrespect for MRI in Stockholm is particularly difficult to understand; but this is not a subject to be discussed at the present place. Solid-state NMR is the third of the three great fields of NMR, powerful already today and very promising for the near future."

This volume contains the written versions of invited lectures and abstracts of seminars presented at the 26th "Universitatswochen fiir Kernphysik" (Uni versity nuclear physics weeks) in Schladming, Austria, in February 1987. Again the generous support of our sponsors, the Austrian Ministry of Sci ence and Research, the Styrian government and others, made it possible to invite expert lecturers. The meeting was organized in honour of Prof. Dr. th Walter Thirring in connection with his 60 birthday. In choosing the topics for the lectures we have tried to cover a good many of the areas in which mathematical physics has made significant progress in recent years. Both classical and quantum mechanical problems are considered as well as prob lems in statistical physics and quantum field theory. The common feature lies in the methods of mathematical physics that are used to understand the underlying structure and to proceed towards a rigorous solution. Thanks to the efforts of the speakers this spirit was maintained in all lectures. Due to space limitations only shortened versions of the many seminars presented in Schladming could be included. After the school the lecture notes were revised by the authors, whom we thank for their efforts, which made it possible to speed up publication. Thanks are also due to Mrs. Neuhold for the careful typing of the notes, and to Miss Koubek and Mr. Preitler for their help in proofreading."