A comprehensive, up-to-date review of the physics and applications of a major class of laser, the most important example of which is the copper vapour laser. A collection of 50 papers written by the world's leaders in the field. Papers cover: the early history of pulsed metal vapour lasters; the plasma kinetics and excitation mechanisms of self terminating and recombination metal vapour lasers; beam quality issues for applications; frequency harmonic generation for mid-UV applications; high-precision processing of metals, ceramics, glasses and plastics using metal vapour lasers; applications in medicine, including oncology and dermatology; applications in science such as spectroscopy and mass spectrometry. A practical source of information on the physics, engineering and applications of metal vapour lasers. Audience: scientists, teachers and graduate researchers working in the fields of gas lasers, laser optics, gas discharges, optoelectronics and laser applications in industry, science and medicine.

Optics at the Nanometer Scale: Imaging and Storing with Photonic Near Fields deals with the fundamentals of and the latest developments and applications of near-field optical microscopy, giving basic accounts of how and under what circumstances superresolution beyond the half- wavelength Rayleigh limit is achieved. Interferometric and fluorescence techniques are also described, leading to molecular and even atomic resolution using light. The storage of optical information at this level of resolution is also addressed.

According to the late Professor Emeritus Seitaro Tsuboi, l the word 'hydrothermal' was used as early as 1849 by a British geologist, Sir Roderick Murchison (1792-187 I), in relation to the action of heated water in bringing about change in the earth's crust. The term abounds in later geological literature, and is most frequently met in connection with the processes that take place at a stage near the closing in the course of consolidation of magma. When a cooling magma reaches that stage, the residual liquid contains a large proportion of volatile components, chiefly water, and further cooling results in the formation of minerals of special interest or ore-deposits. A great concern of Tsuboi's as a petrologist was to elucidate the details of the nature of various actions involved in these 'hydrothermal processes', of which little was known. It is remarkable that, in the last few decades, extensive high-temperature and high-pressure experiments, in which water plays an important role, have become practicable in laboratories, owing to the development of new apparatus and new methods. As a result, the knowledge essential to the elucidation of 'hydrothermal processes' has been improved, but is still far from complete.

R. W. DYSON There will be few readers of this book who are not aware of the contribution that polymers make to modern life. They are to be seen around the home, at work, in transport and in leisure pursuits. They take many forms which include plastic mouldings and extrusions, plastic film and sheet, plastic laminates (fibreglass and formica), rubber gloves, hoses, tyres and sealing rings, fibres for textiles and carpets and so on, cellular products for cushioning and thermal insulation, adhesives and coating materials such as paints and varnishes. The majority of these polymers are synthetic and are derived from oil products. The most important of these in terms of tonnage used are polymers based upon styrene, vinyl chloride, ethylene, propylene and butadiene among plastics and rubber materials, and nylons, polyethyleneterephthalate and poly acrylonitrile among fibres. The total amount of these polymers used each year runs into millions of tonnes. These polymers are sometimes known as commodity polymers because they are used for everyday artefacts. They are available in many grades and formats to meet a variety of applications and processing techniques. The properties can be adjusted by using additives such as heat and light stabilizers, plasticizers, and reinforcing materials. Often, grades are specially designed and formulated to meet particular requirements and, in a sense, these might be regarded as specialities. Much has been written about these materials elsewhere and they are not the concern of this book.

The papers contained herein were presented at the Fifth International Conference on Composite Structures (ICCS/5) held at Paisley College of Technology, Scotland in July 1989. The conference was organised and sponsored by Paisley College of Technology. It was co-sponsored by the Scottish Development Agency, the National Engineering Laboratory, the US Air Force European Office of Aerospace Research and Development, the US Army Research, Development and Standardisation Group-UK, Strathclyde Regional Council and Renfrew District Council. It forms a natural and ongoing progression from the highly successful ICCS/1/2/3 and /4 held at Paisley in 1981, 1983, 1985 and 1987 respectively. It has often been said that at the end of each decade there is much to be gained by reflecting on the manifold factors that have influenced the path of one's life. Doubtless there is much truth in that ancient adage. since it is only by subjectively considering the past that a glimmer of the future is possible.

The literature contains tens of thousands of publications and patents devoted to the synthesis, characterization and processing of polymers. Despite the fact that there are more than one hundred elements, the majority of these publications and patents concern polymers with carbon backbones. Furthermore, the limited (by comparison) number of publications on polymers that contain elements other than carbon in their backbones are typically devoted to polymers based on silicon, especially those with Si-O bonds. This disparity is partially a consequence of the dearth of low cost organometallic feedstock chemicals potentially useful for polymer synthesis. It also derives from the lack of general synthetic techniques for the preparation of organometallic polymers. That is, by comparison with the numerous synthetic strategies available for the preparation of organic polymers, there are few such strategies available for synthesizing tractable, organometallic polymers. In recent years, commerical and military performance requirements have begun to challenge the performance limits of organic polymers. As such, researchers have turned to organometallic polymers as a possible means of exceeding these limits for a wide range of applications that include: (1) microelectronics processing (e.g. photoresists) [1]; (2) light weight batteries (conductors and semi-conductors) [2]; (3) non-linear optical devices [3] and, (4) high temperature structural materials (e.g. ceramic fiber processing) [4,5].

In the last few years it was seen the emergence of various new quantum phenomena specifically related with electronic or optical confinement on a sub-wavelength-size. Fast developments simultaneously occurred in the field of Atomic Physics, notably through various regimes of Cavity Quantum Electrodynamics, and in Solid State Physics, with advances in Quantum Well technology and Nanooptoelectronics. Simultaneously, breakthroughs in Near-Field Optics provided new tools which should be widely applicable to these domains. However, the key concepts used to describe these new and partly related effects are often very different and specific of the Community involved in a given development. It has been the ambition of the Meeting held at "Centre de Physique des Houches" to give an opportunity to specialists of different Communities to deepen their understanding of advances more or less intimately related to their own field, while presenting the basic concepts of these different fields through pedagogical Introductions. The audience comprised advanced students, postdocs and senior scientists, with a balanced participation of Atomic Physicists and Solid State Physicists, and had a truly international character. The considerable efforts of the lecturers, in order to present exciting new results in a language accessible to the whole audience, were the essential ingredients to achieve successfully what was the main goal of this School.

In the last decade, since the publication of the first edition of Scanning Electron Microscopy and X-ray Microanalysis, there has been a great expansion in the capabilities of the basic SEM and EPMA. High resolution imaging has been developed with the aid of an extensive range of field emission gun (FEG) microscopes. The magnification ranges of these instruments now overlap those of the transmission electron microscope. Low-voltage microscopy using the FEG now allows for the observation of noncoated samples. In addition, advances in the develop ment of x-ray wavelength and energy dispersive spectrometers allow for the measurement of low-energy x-rays, particularly from the light elements (B, C, N, 0). In the area of x-ray microanalysis, great advances have been made, particularly with the "phi rho z" Ij)(pz)] technique for solid samples, and with other quantitation methods for thin films, particles, rough surfaces, and the light elements. In addition, x-ray imaging has advanced from the conventional technique of "dot mapping" to the method of quantitative compositional imaging. Beyond this, new software has allowed the development of much more meaningful displays for both imaging and quantitative analysis results and the capability for integrating the data to obtain specific information such as precipitate size, chemical analysis in designated areas or along specific directions, and local chemical inhomogeneities."

"Analytic Insights into Intermediate-Energy Hadron-Nucleus Scattering," by R. D. Amado, presents a review of optical diffraction leading into discussions of elastic scattering, single- and multistep inelastic scattering, spin observables, and directions indicated for further research. "Recent Developments in Quasi-Free Nucleon-Nucleon Scattering," by P. Kitching, W. J. McDonald, Th. A. J. Maris, and C. A. Z. Vascon cellos, opens with a comprehensive review of the theory, going on to detail frontier research advances in spin dependence in (p, 2p) scattering, isospin dependence, and other quasi-free reactions. The final chapter, "Energetic Particle Emission in Nuclear Reactions" by D. H. Boal, explores new findings regarding direct interactions in the nucleus, thermalization and multiple scattering in nucleon emission, light fragment formation, and production of intermediate-mass fragments. A valuable and instructive trio of papers, Volume 15 of Advances in Nuclear Physics will be of interest to nonspecialists as well as specialists in the fields of nuclear physics, high-energy physics, and theoretical physics."

The storage of electroenergy is an essential feature of modem energy technologies. Unfortunately, no economical and technically feasible method for the solution of this severe problem is presently available. But electrochemistry is a favourite candidate from an engineering point of view. It promises the highest energy densities of all possible alternatives. If this is true, there will be a proportionality between the amount of electricity to be stored and the possible voltage, together with the mass of materials which make this storage possible. Insofar it is a matter of material science to develop adequate systems. Electricity is by far the most important secondary energy source. The present production rate, mainly in the thermal electric power stations, is in the order of 1.3 TW. Rechargeable batteries (RB) are of widespread use in practice for electroenergy storage and supply. The total capacity of primary and rechargeable batteries being exploited is the same as that of the world electric power stations. However, the important goal in the light of modem energy technology, namely the economical storage of large amounts of electricity for electric vehicles, electric route transport, load levelling, solar energy utilization, civil video & audio devices, earth and spatial communications, etc. will not be met by the presently available systems. Unless some of the new emerging electrochemical systems are established up to date, RB's based on aqueous acidic or alkali accumulators are mainly produced today.

Chemical modification of polymers by reactive modifiers is no longer an academic curiosity but a commercial reality that has delivered a diverse range of speciality materials for niche markets: reactively grafted styrenic alloys, maleated polyolefins, super-tough nylons, silane modified and moisture-cured polyolefins, and thermoplastic elastomers, are but few exam ples of commercial successes. Although the approach of reactive modification of polymers has been largely achieved either in solution or in the solid state (through in situ reactions in polymer melts), it is the latter route that has attracted most attention in the last two decades owing to its flexibility and cost-effective ness. This route, referred to as reactive processing, focuses on the use of suitable reactive modifier(s) and the adoption of conventional polymer processing machinery, an extruder or a mixer, as a chemical reactor, to perform in situ targeted reactions for chemical modification of preformed polymers. This relatively simple, though scientifically highly challenging, approach to reactive modification offers unique opportunities in exploiting various reactive modifiers for the purpose of altering and transforming in a controlled manner the properties of preformed commercial polymers into new/speciality materials with tailor-made properties and custom-designed performance for target applications. Such an economically attractive route constitutes a radical diversion away from the traditional practices of manufacturing new polymers from monomers which involves massive in vestments in sophisticated technologies and chemical plants."

This volume contains invited and contributed papers of the Ninth International Conference on Hot Carriers in Semiconductors (HCIS-9), held July 3 I-August 4, 1995 in Chicago, Illinois. In all, the conference featured 15 invited oral presentations, 60 contributed oral presentations, and 105 poster presentations, and an international contingent of 170 scientists. As in recent conferences, the main themes of the conference were related to nonlinear transport in semiconductor heterojunctions and included Bloch oscillations, laser diode structures, and femtosecond spectroscopy. Interesting questions related to nonlinear transport, size quantization, and intersubband scattering were addressed that are relevant to the new quantum cascade laser. Many lectures were geared toward quantum wires and dots and toward nanostructures and mesoscopic systems in general. It is expected that such research will open new horizons to nonlinear transport studies. An attempt was made by the program committee to increase the number of presen tations related directly to devices. The richness of nonlocal hot electron effects that were discussed as a result, in our opinion, suggests that future conferences should further encourage reports on such device research. On behalf of the Program and International Advisory Committees, we thank the participants, who made the conference a successful and pleasant experience, and the support of the Army Research Office, the Office of Naval Research, and the Beckman Institute of the University of Illinois at Urbana-Champaign. We are also indebted to Mrs. Sara Starkey and Mrs."

The control of optical modes in microcavities or in photonic bandgap (PBG) materials is coming of age! Although these ideas could have been developed some time ago, it is only recently that they have emerged, due to advances in both atomic physics and in fabrication techniques, be it on the high-quality dielectric mirrors required for high-finesse Fabry Perot resonators or in semiconductor multilayer deposition methods. Initially the principles of quantum electro-dynamics (QED) were demonstrated in elegant atomic physics experiments. Now solid-state implementations are being investigated, with several subtle differences from the atomic case such as those due to their continuum of electronic states or the near Boson nature of their elementary excitations, the exciton. Research into quantum optics brings us ever newer concepts with potential to improve system performance such as photon squeezing, quantum cryptography, reversible taps, photonic de Broglie waves and quantum computers. The possibility of implementing these ideas with solid-state systems gives us hope that some could indeed find their way to the market, demonstrating the continuing importance of basic research for applications, be it in a somewhat more focused way than in earlier times for funding.

The material in this book is based on invited and contributed pa pers presented at the NATO Advanced Research Workshop on INon-stoichio l metric Compounds held in Ringberg Castle, Rottach-Egern (Bavarian Alps), Germany, July 3-9, 1988. The workshop followed previous meetings held in Mogilany, Poland (1980), Alenya, France (1982), Penn State, USA (1984) and Keele University, UK (1986). The aim of these workshops is to present and discuss up-to-date knowledge in the study of non-stoichiometry and its effect on materials properties as well as to indicate the most urgent research pathways required in this field. Since the subject of non-stoichiometry is interdisciplinary, the workshops bring together solid state physicists and chemists, surface scientists, materials scientists, ceramists and metallurgists. The present workshop, which gathered 42 scientists of an inter national reputation, mainly considered the effect of surfaces, grain boundaries and structural defects on materials properties. From discus sions during this meeting it emerged that correct understanding of properties of ceramic materials requires urgent studies on the defect structure of the interface region. Progress in this direction requires the development of the interface defect chemistry. This is the task for materials scientists in the near future. The present proceedings includes both theoretical and experimen tal work on general aspects of non-stoichiometry, defect structure and diffusion in relation to the bulk and to the interface region of such materials as high tech ceramics, solid electrolytes, electronic cera mics, nuclear materials and high Tc oxide superconductors."

The International Thermal Conductivity Conference was started in 1961 with the initiative of Mr. Charles F. Lucks and grew out of the needs of researchers in the field. The Conferences were held annually from 1961 to 1973 and have been held biennially since 1975 when our Center for Informa tion and Numerical Data Analysis and Synthesis (CINDAS) of Purdue University became the Permanent Sponsor of the Conferences. -These Conferences provide a broadly based forum for researchers actively working on the thermal con ductivity and closely related properties to convene on a regular basis to exchange their ideas and experiences and report their findings and results. The Conferences have been self-perpetuating and are an example of how a technical community with a common purpose can transcend the invisible. arti ficial barriers between disciplines and gather together in increasing num bers without the need of national publicity and continuing funding support. when they see something worthwhile going on. It is believed that this ser ies of Conferences not only will grow stronger. but will set an example for researchers in other fields on how to jointly attack their own problem areas."

Proceedings of the NATO Advanced Study Institute, San Miniato, Italy, September 2-13, 1985

The proceedings of the "International Conference on Spin Observables of Nuclear Probes" are presented in this volume. This conference was held in Telluride, Colorado, March 14-17, 1988, and was the fourth in the Telluride series of nuclear physics conferences. A continuing theme in the Telluride conference series has been the complementarity of various intermediate-energy projectiles for elucidating the nucleon-nucleon interaction and nuclear structure. Earlier conferences have contributed significantly to an understanding of spin currents in nuclei, in particular the distribution of Gamow-Teller strength using charge-exchange reactions. The previous conference on "Antinucleon and Nucleon Nucleus Interactions" compared nuclear information from tra tional probes to recent results from antinucleon reactions. The 1988 conference on Spin Observables of Nuclear Probes, put special emphasis on spin observables and brought together experts using spin information to probe nuclear structure. Spin observables have provided very detailed information about nuclear structure and reactions. Since the 1985 Telluride conference we have seen data from new focal plane polarimeters at LAMPF, TRIUMF, IUCF and elsewhere. In addition, spin observables provide an important common ground between electron and hadron scattering physics. In the future we look forward to new facilities such as NTOF for polarized neutron measurements at Los Alamos and a vigorous spin program at CEBAF."

Integral geometry deals with the problem of determining functions by their integrals over given families of sets. These integrals de?ne the corresponding integraltransformandoneofthemainquestionsinintegralgeometryaskswhen this transform is injective. On the other hand, when we work with complex measures or forms, operators appear whose kernels are non-trivial but which describe important classes of functions. Most of the questions arising here relate, in one way or another, to the convolution equations. Some of the well known publications in this ?eld include the works by J. Radon, F. John, J. Delsarte, L. Zalcman, C. A. Berenstein, M. L. Agranovsky and recent monographs by L. H] ormander and S. Helgason. Until recently research in this area was carried out mostly using the technique of the Fourier transform and corresponding methods of complex analysis. In recent years the present author has worked out an essentially di?erent methodology based on the description of various function spaces in terms of - pansions in special functions, which has enabled him to establish best possible results in several well known problems."

A fundamental knowledge and understanding of dental materials is an absolute requisite to performing optimal dental care. This tenet is true not only for general dentists, but also for specialists alike. It is true not only for the developing dental student, but also for the practicing dentist. It is clearly evident that the authors of Dental Biomaterials have both an in-depth knowledge of dental materials and a fundamental appreciation for the importance of this information in contemporary clinical dentistry. Owing to the broad range of expertise of the authors, this textbook distinguishes itself from most dental materials texts by its remarkable ability to address a myriad of dental materials in the context of actual clinical applications. Emphasizing the clinical significance of dental materials is an obvious and conspicuous goal of this text that pervades the entire content of its pages. In fact, to that end, the authors notably include numerous highlighted sections entitled "Dental Significance" throughout the chapters to underscore the clinical importance of the subject matter. This approach is exceptionally effective at fostering a basic understanding of dental materials for the dental student. It piques the interest without stifling the student with abstract concepts. This text also is a valuable and reliable resource for the practicing dentist.

The IUT AM Symposium on "Micromechanics of Plasticity and Damage of Multiphase Materials" was held in Sevres, Paris, France, 29 August - 1 September 1995. The Symposium was attended by 83 persons from 18 countries. In addition 17 young French students attended the meeting. During the 4 day meeting, a total of 55 papers were presented, including 24 papers in the poster sessions. The meeting was divided into 7 oral and 3 poster sessions. The 7 oral sessions were the following: - Plasticity and Viscoplasticity I and II; - Phase transformations; - Damage I and II; - Statistical and geometrical aspects; - Cracks and interfaces. Each poster session was introduced by a Rapporteur, as follows: - Session I (Plasticity and Viscoplasticity): G. Cailletaud; - Session 2 (Damage): D. Franc;:ois; - Session 3 (Phase transformation; statistical and geometrical aspects): D. Jeulin. The main purpose of the Symposium was the discussion of the state of the art in the development of micromechanical models used to predict the macroscopic mechanical behaviour of mUltiphase solid materials. These materials consist of at least two chemically different phases, present either initially or formed during plastic deformation, when a strain-induced phase transformation takes place. One session was devoted to the latter case. Continuously strengthened composite materials, containing long fibers, were out of the scope of the Symposium.

As ironmakers are well aware, it was only a few decades ago that the blast furnace was viewed as a strange 'black box'. Recently, however, various in-furnace phenomena have become the subject of serious scientific study, largely as the result of the 'dissection' of dead furnaces, together with the development of advanced monitoring and control techniques. In this way, a new frontier has been opened within the venerable domain of metallurgy. In the light of these new developments, the Committee on Reaction within Blast Furnaces was set up in March 1977 by the Joint Society ofIron and Steel Basic Research - a cooperative research organization of the Iron and Steel Institute of Japan (ISIJ), the Japan Institute of Metals (JIM) and the Japan Society for the Promotion of Science (JSPS). Consisting of twenty-six members and advisors drawn from the fields of academia and industry, this committee collected, discussed, and evaluated numerous papers during its five year commission. Particular attention was paid to the interpretation of findings drawn from the autopsy of dead furnaces, in the context of the live furnace state, and the correlation of data regarding cohesive zone configuration, level, and furnace performance. The results of this intense research activity are presented here in the hope that they will serve not only as a source of enrichment to the professional knowledge of researchers and operators, but also as textual material for graduate students in the field of metallurgy."

I wish to express my full indebtedness to all researchers in the field. Without their outstanding contribution to knowledge, this book would not have been written. The author wishes to express his sincere thanks and gratitude to Professors M. F. Ashby (University of Cambridge), N. D. Cristescu (University ofFlorida), N. Davids (The Pennsylvania State University), H. F. Frost (Dartmouth College), A W. Hendry (University of Edinburgh), F. A Leckie (University of California, Santa Barbara), A K. Mukherjee (University of California, Davis), T. Nojima (Kyoto University), J. T. Pindera (University of Waterloo), J. W. Provan (University of Victoria), K. Tanaka (Kyoto University), Y Tomita (Kobe University) and G. A Webster (Imperial College), and to Dr. H. J. Sutherland (Sandia National Laboratories). Permission granted to the author for the reproduction of figures and/or data by the following scientific societies, publishers and journals is gratefully acknowledged: ASME International, ASTM, Academic Press, Inc. , Addison Wesley Longman (Pearson Education), American Chemical Society, American Institute of Physics, Archives of Mechanics I Engineering Transactions (archiwum mechaniki stosawanej I rozprawy inzynierskie, Warsaw, Poland), British Textile Technology Group, Butterworth-Heinemann Ltd. (USA), Chapman & Hall Ltd. (International Thomson Publishing Services Ltd. ), Elsevier Science-NL (The Netherlands), Elsevier Science Limited (U. K. ), Elsevier SequoiaS. A (Switzerland), John Wiley & Sons, Inc. , lOP Publishing Limited (UK), Kluwer Academic Publishers (The Netherlands), Les Editions de Physique Les Ulis (France), Pergamon Press Ltd. (U. S. A), Society for Experimental Mechanics, Inc.

Over the years the aim of the International Conference on Magnet Technology has been the exchange of information on the design, construction and operation of magnets for a variety of applications, such as high energy physics, fusion, electrical machinery and others. The aim has included advances in materials for magnet conductors, insulators and supporting structures. Since its inception the focus of the International Conference on Magnet Technology has gradually shifted to superconducting magnets. Now almost all papers are related to superconductivity. The 11th International Conference on Magnet Technology (MT-11) was organized by the combined efforts of the Institute of Electrical Engineers of Japan, the Association for Promotion of Electrical, Electronic and Information Engineering, and the Tokyo Section of the IEEE. The Conference was held at the Tsukuba University Hall, Tsukuba, Japan, from 28 August to 1 September 1989, courtesy ofthe University ofTsukuba. The Tsukuba University Hall was large enough to host invited talks, parallel sessions, poster sessions and industrial exhibitions. 461 participants from 19 countries registered for MT-ll, and 280 invited and contributed papers were presented. The papers were reviewed not only by the Program Committee but also by foreign participants. Working sessions and social events were characterized by a truly international atmo sphere. Scientific as well as cultural excursions were organized so that foreign visitors could experience the spirit of modern Japan. 26 companies, of which 8 were from Western countries, participated in the industrial exhibition which featured diverse products and services of interest to the magnet community."

There is a need to solve problems in solid and fluid mechanics that currently exceed the resources of current and foreseeable supercomputers. The issue revolves around the number of degrees of freedom of simultaneous equations that one needs to accurately describe the problem, and the computer storage and speed limitations which prohibit such solutions. The goals of tHis symposium were to explore some of the latest work being done in both industry and academia to solve such extremely large problems, and to provide a forum for the discussion and prognostication of necessary future direc tions of both man and machine. As evidenced in this proceedings we believe these goals were met. Contained in this volume are discussions of: iterative solvers, and their application to a variety of problems, e.g. structures, fluid dynamics, and structural acoustics; iterative dynamic substructuring and its use in structural acoustics; the use of the boundary element method both alone and in conjunction with the finite element method; the application of finite difference methods to problems of incompressible, turbulent flow; and algorithms amenable to concurrent computations and their applications. Furthermore, discussions of existing computational shortcomings from the big picture point of view are presented that include recommendations for future work."

Six years passed by since the NATO ASI on "Liquid and Amorphous Metals" was held in Zwiesel, Germany, in September 1979. The present one is the second NATO School devoted to research on disordered condensed matter, mainly liquid and amorphous metals. This time the title contains the word "materials" to explicitely include those aspects of the glassy state of insulators either shared with metallic glasses - e.g. the glass tran sition - or on the border line with metallic systems - e.g. the metal non-metal transition. The long period which purposely elapsed between the two Institutes indi cates the intention not to have "just another conference," but to review the state of affairs in the field with a somewhat more durable scope. This is especially important to help basic research to bridge towards applica tions and to introduce young researchers in this field. In fact, while the understanding of these materials and their properties is a tremendous challenge for experimental and theoretical physicists, glassy substances offer an enormous potential in-the development of new materials for tech nical applications. To this end, the Institute has brought together insiders and peers from allover the world to discuss basic principles and latest results and to help correlate future research effort. Another important aim was to intro duce newcomers to the field."