In this introductory text, Dr. Birdi demonstrates experimental methods and analyses of fractal dimensions in natural processes. In addition to a general overview, he discusses in detail problems in the fields of chemistry, geochemistry, and biophysics. Both students and professionals with a minimum of mathematics or physical science training will learn to find and model shapes and patterns from their own everyday observations.

In the last decade, research on platelet-activating factor (PAF) has expanded exponentially. Previous conferences on PAF in Paris, 1983, and the subsequent conferences in Gatlinburg, Ten nessee, Tokyo, Snowbird, Utah, and Berlin, at three-yearly intervals, have chronicled the devel opments in the field ofPAF. This volume records the proceedings of the Fifth International Con gress on PAF and Related Lipid Mediators, held at the Free University Medical Hospital Ben jamin Franklin in Berlin, from September 12-16, 1995. We are very much indebted to Free Uni versity Berlin for providing tremendous facilities and financial support. It was a great pleasure to have positive and generous input from the German Science Council (DFG), Bonn, Germany, and British.Biotech, Oxford, United Kingdom. Their support was crucial in making the congress a scientific success. Twenty other organizations provided additional financial support, for which we extend our deepest appreciation. The editors would like to thank all of those who participated in this congress and the authors for their contributions. The organization and planning of the Berlin Congress were carried out by an organizing committee. We gratefully acknowledge the support and assistance of the organizing commit tee members, especially Renate Nigam and Renate Roux for their untiring efforts to make the congress successful. Many colleagues also supported the congress with dedication, hard work, and expert input. We are grateful to them. We also wish to acknowledge the support of G. Sravan Kumar and Louis Kock for their efforts in producing this volume."

A number of factors have come together in the last couple of decades to define the emerging interdisciplinary field of structural molecular biology. First, there has been the considerable growth in our ability to obtain atomic-resolution structural data for biological molecules in general, and proteins in particular. This is a result of advances in technique, both in x-ray crystallography, driven by the development of electronic detectors and of synchrotron radiation x-ray sources, and by the development ofNMR techniques which allow for inference of a three-dimensional structure of a protein in solution. Second, there has been the enormous development of techniques in DNA engineering which makes it possible to isolate and clone specific molecules of interest in sufficient quantities to enable structural measurements. In addition, the ability to mutate a given amino acid sequence at will has led to a new branch of biochemistry in which quantitative measurements can be made assessing the influence of a given amino acid on the function of a biological molecule. A third factor, resulting from the exponential increase in computing power available to researchers, has been the emergence of a growing body of people who can take the structural data and use it to build atomic-scale models of biomolecules in order to try and simulate their motions in an aqueous environment, thus helping to provide answers to one of the most basic questions of molecular biology: the relation of structure to function.

In the past few years, the scientific community has witnessed significant progress in the study of ion channels. Technological advancement in biophysics, molecular biology, and immunology has been greatly ac celerated, making it possible to conduct experiments which were deemed very difficult if not impossible in the past. For example, patch-clamp techniques can now be used to measure ionic currents generated by almost every type of cell, thereby allowing us to analyze whole-cell and single channel events. It is now possible to incorporate purified ion channel components into lipid bilayers to reconstitute an "excitable membrane." Gene cloning and monoclonal antibody techniques provide us with new approaches to the study of the molecular structure of ion channels. A variety of chemicals have now been found to interact with ion channels. One of the classical examples is represented by tetrodotoxin, a puffer fish poison, which was shown in the early 1960s to block the voltage-activated sodium channel in a highly specific and potent manner.

This book was originated from a series of lectures given in a course on the physical properties of biological membranes and their functional implica tions. The course was intended to allow students to get acquainted with the physical techniques used to study biological membranes. The experience was valuable and we feel that a detailed description of the procedures used and of various examples of the results obtained allowed many students to become familiar with a theme that is not often part of regular courses on membrane physiology or biophysics. This book is designed as a tutorial guide for graduate students interested in understanding how physical methods can be utilized to study the proper ties of biological membranes. It includes first a detailed description of applications of physical techniques-such as X-ray fiber diffraction methods (Chapter 1), 2H and 13C NMR spectroscopy (Chapter 2), and calorimetry (Chapter 3)-in the study of the properties of lipid model membranes. A description of how to measure molecular mobility in membranes (Chapter 4) follows, and the book concludes with three chapters in which biological membranes are the subject of study. Chapter 5 deals with the acetylcholine receptor and its membrane environment; Chapter 6 discusses how fluorescence techniques can be applied in the study of the calcium ATPase of sarcoplasmic reticulum; and Chapter 7 explains how protein lipid interactions modulate the function of the sodium and proton pumps."

This book is dedicated to the memory of two colleagues and friends, Amico Big- nami and Hendrick Vander Los. They were both pioneers in their fields: Bignami on on- togenesis and function of neuroglia, and Van der Los on brain plasticity and neuronal circuitry. Their ideas are further pursued by the authors in this book. Some of the chapters are products of a conference dedicated to these two scientists entitled "Recent Advances in Neurobiology: Plasticity and Regeneration." The conference was organized by the Insti- tute of Developmental Neuroscience and Aging and sponsored by the Region della Valle d' Aosta. Also, several chapters are written by colleagues who knew well either Amico or Hendrick and were invited to contribute to this dedication. The book is divided in four sections. The first part covers neurons, neuroglia includ- ing microglia, their plasticity and phenotypic expression, and specific functions and inter- actions. It is now established that neuroglia are an intimate component of the neuronal environment and thought to regulate several neuronal functions. More recently microglia have become prominent as the immune cells in the CNS. This part contributes new infor- mation for these cellular interactions. The second part deals with neuronal and glial cell plasticity as it relates to regeneration and neurodegeneration, more or less an extension of Part I. In recent years the role of transplantation in regeneration has become promising.

In recent years experimental and numerical studies have shown that chaos is a widespread phenomenon throughout the biological hierarchy ranging from simple enzyme reactions to ecosystems. Although a coherent picture of the fundamental mechanisms responsible for chaotic dynamics has started to appear it is not yet clear what the implications of such dynamics are for biological systems in general. In some systems it appears that chaotic dynamics are associated with a pathological condi tion. In other systems the pathological condition has regular periodic dynamics whilst the normal non-pathological condition has chaotic dyna mics. Since chaotic behaviour is so ubiquitous in nature and since the phenomenon raises some fundamental questions about its implications for biology it seemed timely to organize an interdisciplinary meeting at which leading scientists could meet to exchange ideas, to evaluate the current state of the field and to stipulate the guidelines along which future research should be directed. The present volume contains the contributions to the NATO Advanced Research Workshop on "Chaos in Biological Systems" held at Dyffryn House, St. Nicholas, Cardiff, U. K., December 8-12, 1986. At this meeting 38 researchers with highly different backgrounds met to present their latest results through lectures and posters and to discuss the applica tions of non-linear techniques to problems of common interest. . In spite of their involvement in the study of chaotic dynamics for several years many of the participants met here for the first time."

I have been asked to write a brief foreword to this volume honoring Hisako Ikeda, providing a review of the accomplishments in our field over the past four decades, when Hisako was an active participant. This I am delighted to do. It has been a most exciting time in vision research and Hisako has been right in the middle of much of the excitement, publishing on a wide variety of topics and providing much new data and many new insights. Hisako's research career can be divided by decades into four quite distinct areas of inquiry. In the 1950s, as a student in Japan, her research interests were psychophysical in nature, and she was concerned with visual illusions, figural aftereffects, and motion detec tion. In the 1960s, after her move to London, she began electrophysiological studies. Much of her work in the 1960s was concerned with the electroretinogram (ERG), its components, and the use of this electrical response for evaluating spectral sensitivities of the eye and retinal degenerations. This work represented the beginning of her electrodiagnostic clinical work, which continued until her retirement."

William P. Cooney III, R. A. Berger, and K. N. An Orthopedic Biomechanics Laboratory Department of Orthopedic Surgery Mayo Clinic and Mayo Foundation Rochester, MN 55905, U. S. A. As surgeons struggle to find new insights into the complex diseases and deformities that involve the wrist and hand, new insights are being provided by applied anatomy, physiology and biomechanics to these important areas. Indeed, a fresh new interaction of disciplines has immersed in which anatomists, bioengineers and surgeons examine together basic functions and principles that can provide a strong foundation for future growth. Clinical interest in the hand and wrist are now at a peak on an international level. Economic implications of disability affecting the hand and wrist are recognized that have international scope crossing oceans, cultures, languages and political philosophies. As with any struggle, a common ground for understanding is essential. NATO conferences such as this symposium on Biomechanics of the Hand and Wrist provides such a basis upon which to build discernment of fundamental postulates. As a start, basic research directed at studies of anatomy, pathology and pathophysiology and mechanical modeling is essential. To take these important steps further forward, funding from government and industry are needed to consider fundamental principles within the material sciences, biomechanical disciplines, applied anatomy and physiology and concepts of engineering modeling that have been applied to other areas of the musculoskeletal system.

Fluorescence microscopy images can be easily integrated into current video and computer image processing systems. People like visual observation; they like to watch a television or computer screen, and fluorescence techniques are thus becoming more and more popular. Since true in vivo experiments are simple to perform, samples can be directly seen and there is always the possibility of manipulating the samples during the experiments; it is an ideal technique for biology and medicine. Images are obtained by a classical (now called wide-field) fluorescence microscope, a confocal scanning microscope, upright or inverted, with epifluorescence or transmission. Computerized image processing may improve definition, and remove glare and scattered light signal. It also makes it possible to compute ratio images (ratio imaging both in excitation and in emission) or lifetime imaging. Image analysis programs may supply a great deal of additional data of various types, starting with calculations of the number of fluorescent objects, their shapes, brightness, etc. Fluorescence microscopy data may be complemented by classical measurement in the cuvette yr by flow cytometry.

This text attempts to introduce the molecular biology of cell membranes to students and professionals of diverse backgrounds. Although several membrane biology books are available, they do not integrate recent knowledge gained using modern molecular tools with more traditional membrane topics. Molecular techniques, such as cDNA cloning and x-ray diffraction, have provided fresh insights into cell membrane structure and function. The great excitement today, which I attempt to convey in this book, is that molecular details are beginning to merge with physiological responses. In other words, we are beginning to understand precisely how membranes work. This textbook is appropriate for upper-level undergraduate or beginning graduate students. Readers should have previous or concurrent coursework in biochemistry; prior studies in elementary physiology would be helpful. I have found that the presentation of topics in this book is appropriate for students of biology, biochemistry, biophysics and physiology, chemistry, and medicine. This book will be useful in courses focusing on membranes and as a supplementary text in biochemistry courses. Professionals will also find this to be a useful resource book for their personal libraries.

Amino acid transport is a part of each of two larger subjects, amino acid metabolism and the biomembrane transport of various . small molecules and ions. Nevertheless in this volume we treat amino acid transport as more than a fragment of either of these two larger subjects. A more comprehensive approach is justified when we remember two historic and ongoing aspects of the title subject. First, amino acid transport had its beginning and acquired a distinct momentum (even if somewhat interrupted from 1913 until about 1945) as amino acid metabolism with the central and pioneer work of Van Slyke and Meyer in 1913. The reviews in this volume will show that it steadily becomes a larger aspect of amino acid metabolism, broadly perceived. These chapters will show for how many organelles, cells, tissues, organs and organ systems, the transmembrane compartmentations and flows of amino acids play very large parts in their fundamental biological relations. The authors here are tending collectively to evaluate an understanding of amino acid flows across biomernbranes, and the regulation of these flows, as necessary to an ultimate understanding of the full range of development and metabolism. Such an understanding goes far beyond the purely substrate-destabilizing contributions by enzymes, which have often been arbitrarily limited to that conceptual entity, "the cell," and which for so long a splendid time had most of biochemical research attention.

During the past few decades, much research has been reported on the formation of insoluble monomolecular films of lipids and biopolymers (synthetic polymers and proteins) on the surface of water or at the oil-water interface. This interest arises from the fact that monomolecular film studies have been found to provide much useful information on a molecular scale, information that is useful for understanding many industrial and biological phenomena in chemical, agricultural, pharmaceutical, medical, and food science applications. For instance, information obtained from lipid monolayer studies has been useful in determining the forces that are known to stabilize emulsions and biological cell membranes. The current texts on surface chemistry generally devote a single chapter to the characteristics of spread monolayers of lipids and biopolymers on liquids, and a researcher may have to review several hundred references to determine the procedures needed to investigate or analyze a particular phenomenon. Furthermore, there is an urgent need at this stage for a text that discusses the state of the art regarding the surface pheqomena exhibited by lipids and biopolymers, as they are relevant to a wide variety of surface and interfacial processes.

The past decade has seen a steady increase in studies oflemur behavior and ecology. As a result, there is much novel information on newly studied populations, and even newly discovered species, that has not yet been published or summarized. In fact, lemurs have not been the focus of an international symposium since the Prosimian Biology Conference in London in 1972. Moreover, research on lemurs has reached a new quality by addressing general issues in behavioral ecology and evolutionary biology. Although lemurs provide important comparative information on these topics, this aspect of research on lemurs has not been reviewed and compared with similar studies in other primate radiations. Thus, as did many in the field, we felt that the time was ripe to review and synthesize our knowledge of lemur behavioral ecology. Following an initiative by Gerry Doyle, we organized a symposium at the XIVth Congress of the International Primatological Society in Strasbourg, France, where 15 contributions summarized much new information on lemur social systems and their ecological basis. This volume provides a collection of the papers presented at the Strasbourg symposium (plus two reports from recently completed field projects). Each chapter was peer-reviewed, typically by one "lemurologist" and one other biologist. The first three chapters present novel information from the first long-term field studies of three enigmatic species. Sterling describes the social organization of Daubentonia madagascariensis, showing that aye-aye ranging patterns deviate from those of all other nocturnal primates.

This book focuses on sensing and the evolution of animals. Using the five senses (visual, auditory, and olfactory perception, and taste and touch), animals can receive environmental stimuli and respond to them. Changes in these sensitivities might cause changes in aspects of animals lives such as habitat, activity timing, and diet and vice versa. Recent advances in genome and molecular analysis enable us to investigate certain changes in the receptors or mechanisms involved in sensing and provide clues for understanding the evolution of animals related to those changes. The first chapter deals with the molecular evolution of opsins. In addition to the well-known function of opsins as visual receptors, opsins can be related to non-visual photoreception such as photoentrainment of circadian rhythm, photoperiodism, and background adaptation. Molecular phylogenic studies reveal that all opsin genes have evolved from one ancient opsin gene. The evaluation of the functions of each extant opsin protein based on the molecular features enables us to predict the molecular evolution and diversification of opsins during the evolution of animals. These studies shed light on which amino-acid substitutions cause the functional diversification of opsins and how they have influenced the evolution of animals. The second chapter has to do with bitter taste perception, a key detection mechanism against the ingestion of bioactive substances. Genetic and behavioral evidence reveal the existence of "non-taster" Japanese macaques for specific bitter compounds, which originated in a restricted region of Japan. This finding might provide a clue for elucidating the ecological, evolutionary, and neurobiological aspects of bitter taste perception of primates. The third chapter presents an extreme example of the evolution of olfaction, namely, that fully aquatic amniotes have generally reduced their olfactory capacity considerably compared to their terrestrial relatives. Interestingly, the remaining olfactory abilities are quite different among three fully aquatic amniotes investigated: toothed whales have no nervous system structures that mediate olfaction, but baleen whales can smell in air, and it has been suggested that sea snakes smell underwater."

Methods in Bone Biology is unique in being devoted to describing the methodology used by bone researchers. This book describes in detail the techniques of cell and organ culture used in the study of bone and bone cell function and the techniques used to monitor the skeleton and skeletal remodelling both in clinical and experimental settings.

Charles E. Hess Department of Environmental Horticulture University of California Davis, CA 95616 Research in the biology of adventitious root formation has a special place in science. It provides an excellent forum in which to pursue fundamental research on the regulation of plant growth and development. At the same time the results of the research have been quickly applied by commercial plant propagators, agronomists, foresters and horticulturists (see the chapter by Kovar and Kuchenbuch, by Ritchie, and by Davies and coworkers in this volume). In an era when there is great interest in speeding technology transfer, the experiences gained in research in adventitious root formation may provide useful examples for other areas of science. Interaction between the fundamental and the applied have been and continue to be facilitated by the establishment, in 1951, of the Plant Propagators' Society, which has evolved into the International Plant Propagators' Society, with active programs in six regions around the world. It is a unique organization which brings together researchers in universities, botanical gardens and arboreta, and commercial plant propagators. In this synergistic environment new knowledge is rapidly transferred and new ideas for fundamental research evolve from the presentations and discussions by experienced plant propagators. In the past 50 years, based on research related to the biology of adventitious root formation, advances in plant propagation have been made on two major fronts.

The fifth Oxford Conference was held on September 17th-19th, 1991, at the Fuji Institute of Training in Japan -the first time that the meeting has taken place in the Asian area. The facts that only a relatively few Japanese had attended previous Oxford Conferences and that Japan is far from other regions with possible participants made the organizers anticipate a small attendance at the meeting. However, contrary to our expectations, 198 active members (72 foreign and 126 domestic participants) submitted 146 papers from 15 countries. This was far beyond our preliminary estimate and could have caused problems in providing accommodation for the participants and in programming their scientific presentations. These difficulties, however, were successfully overcome by using nearby hotels, by telecasting presentations into a second lecture room and by displaying a substantial number of poster presentations during the whole period of the meeting. The meeting had two types of sessions: regular and current topics. The first paper in each session represented a shon overview or introduction so as to make it easier for the audience to comprehend the problems at issue. Because of the large number of papers submitted, carefully selected speakers (mostly well-known scholars) made excellent presentations that were followed by lively discussions. In this way, the conference laid a foundation on which to base its continued scientific success.

Pulmonary Biology in Health and Disease was conceived as a companion to a handful of expensive, multivolume textbooks. This is part of the promising trend to publish shorter textbooks on the subjects of lung biology and remodeling. Whoever is familiar with human biology and the far-reaching consequences of the genome and postgenome revolutions is apt to concede that the centerpiece in remodeling lies in the ?eld of m- ecular cardiobiology. The ?eld of molecular cardiobiology includes the syndrome of chronic heart failure as well as ischemic cardioprotection. By analogy, the centerpiece in pulmonobiology is chronic asthma. Key topics in the present volume include s- naling mechanisms regulating the endothelium and smooth muscle cells,in?ammatory cells, mediators, airway surface liquid, and pharmacological therapy that focuses on how in?amed airways are altered. Written primarily for predoctoral and postdoctoral graduates in the basic medical sciences, the medical student and postdoctoral physician, graduates in the allied s- ences, nurses, pulmonologists, and physicians in critical care medicine, this book p- vides many of the fundamentals of contemporary pulmonology. It is divided into several parts devoted to the control of respiration, arterial chemoreceptors,muscles of ventilation, pulmonary physiology, and gas exchange in health, exercise, and disease. Special emphasis is placed on emphysema and its pathobiology, acute lung injury, asthma and inhaled toxicants. Because the ?eld is always evolving, each chapter includes recommended readings that lead the reader to sources of additional information, such as the review on remodeling of the blood gas barrier by West and Mathieu-Costello.

This is a book about how Cl- crosses the cell membranes of nerve, muscle, and glial cells. Not so very many years ago, a pamphlet rather than book might have resulted from such an endeavor! One might ask why Cl-, the most abundant biological anion, attracted so little attention from investigators. The main reason was that the prevailing paradigm for cellular ion homeostasis in the 1950s and 1960s assigned Cl- a ther modynamically passive and unspecialized role. This view was particularly prominent among muscle and neuroscience investigators. In searching for reasons for such a negative (no pun intended) viewpoint, it seems to us that it stemmed from two key experimental observations. First, work on frog skeletal muscle showed that Cl- was passively distributed between the cytoplasm and the extracellular fluid. Second, work on Cl- transport in red blood cells confirmed that the Cl- transmembrane distribution was thermodynamically passive and, in addition, showed that Cl- crossed the mem brane extremely rapidly. This latter finding [for a long time interpreted as being the result of a high passive chloride electrical permeability(? CI)] made it quite likely that Cl- would remain at thermodynamic equilibrium. These two observations were gener alized and virtually all cells were thought to have a very high P Cl and a ther modynamically passive Cl- transmembrane distribution. These concepts can still be found in some physiology and neuroscience textbooks.

This book is based on a series of lectures for a course on ionic channels held in Santiago, Chile, on November 17-20, 1984. It is intended as a tutorial guide on the properties, function, modulation, and reconstitution of ionic channels, and it should be accessible to graduate students taking their first steps in this field. In the presentation there has been a deliberate emphasis on the spe cific methodologies used toward the understanding of the workings and function of channels. Thus, in the first section, we learn to "read" single channel records: how to interpret them in the theoretical frame of kinetic models, which information can be extracted from gating currents in re lation to the closing and opening processes, and how ion transport through an open channel can be explained in terms of fluctuating energy barriers. The importance of assessing unequivocally the origin and purity of mem brane preparations and the use of membrane vesicles and optical tech niques in the stUGY of ionic channels are also discussed in this section. The patch-clamp technique has made it possible to study ion channels in a variety of different cells and tissues not amenable to more conven tional electrophysiological methods. The second section, therefore, deals with the use of this technique in the characterization of ionic channels in different types of cells, ranging from plant protoplasts to photoreceptors.

Every coordination within or between animals depends on communication processes. Although the signaling molecules, vocal and tactile signs, gestures and its combinations differ throughout all species according their evolutionary origins and variety of adaptation processes, certain levels of biocommunication can be found in all animal species:

(a) Abiotic environmental indices such as temperature, light, water, etc. that affect the local ecosphere of an organism and are sensed, interpreted.

(b) Trans-specific communication with non-related organisms.

(c) Species-specific communication between same or related species.

(d) Intraorganismic communication, i.e., sign-mediated coordination within the body of the organism.

This book gives an overview of the manifold levels of animal communication exemplified by a variety of species and thereby broadens the understanding of these organisms.

"

It is now over 30 years since the idea of ion-conducting pores burst on the elec- trophysiological scene, 15 years since these were generalIy realized to be mem- brane-spanning proteins, and 10 years since the first observations of single ion channels from higher organisms were made. During the past 5 years, several integral membrane channel proteins have been purified in a functionalIy competent state: the nicotinic acetylcholine receptor, the Na + channel, mitochondrial "VDAC," and a variety of porins. The stage is thus set to attack ion channels in the same ways that biochemists have been attacking enzymes for decades: isolation folIowed by functional analysis in as simple a system as possible, with a view towards understanding the molecular mechanisms ofthe protein's behavior and how this is related to the underlying molecular structure. This is always a daunting task, alI the more so with ion channels because of our still primitive and scanty understanding of channel structures and because of the difficulty in iso- lating functionally active channel proteins. In this volume, which can be considered a biochemically slanted companion to Sakmann and Neher's Single-Channel Recording, I have tried to present a view of the current landscape of ion-channel reconstitution. These chapters illustrate not only the different approaches and techniques of the major practitioners of ion- channel reconstitution but, as importantly, the varied motivations for doing this kind of work.