The study of how solar- and lunar- related rhythms are governed by living pacemakers within organisms constitutes the scientific discipline of chronobiology. Few fields encompass the breadth of science that is associated with this subject, which is at the cutting edge of fields ranging from microbial genetics to ethology to treatment of human psychiatric illnesses. In order to recognise that no individual could do justice to the field in writing a comprehensive text, a group of experienced editors and contributors have collaborated to produce Chronobiology. Written in a clear style and fully illustrated to elucidate difficult points, the book assumes no previous background in neuroscience or maths and reduces technical terminology to a minimum. Examples from the real world and from current and classic research are included.

Circadian rhythms are such an innate part of our lives that we rarely pause to speculate why they even exist. Some studies have suggested that the disruption of the circadian system may be causal for obesity and manifestations of Metabolic Syndrome (MetS). Shift-work, sleep-deprivation and bright-light-exposure at night are related to increased adiposity (obesity) and prevalence of MetS. It has been provided evidence of clock genes expression in human adipose tissue and demonstrated its association with different components of the MetS. Moreover, current studies are illustrating the particular role of different clock genes variants and their predicted haplotypes in MetS. The purpose of “Chronobiology and Obesity” is to describe the mechanisms implicated in the interaction between chonodisruption and metabolic-related illnesses, such as obesity and MetS, with different approaches.

Every aspect of immune function and host defense is dependent upon a proper supply and balance of nutrients. Severe malnutrition can cause significant alteration in immune response, but even subclinical deficits may be associated with an impaired immune response, and an increased risk of infection. Infectious diseases have accounted for more off-duty days during major wars than combat wounds or nonbattle injuries. Combined stressors may reduce the normal ability of soldiers to resist pathogens, increase their susceptibility to biological warfare agents, and reduce the effectiveness of vaccines intended to protect them. There is also a concern with the inappropriate use of dietary supplements. This book, one of a series, examines the impact of various types of stressors and the role of specific dietary nutrients in maintaining immune function of military personnel in the field. It reviews the impact of compromised nutrition status on immune function; the interaction of health, exercise, and stress (both physical and psychological) in immune function; and the role of nutritional supplements and newer biotechnology methods reported to enhance immune function. The first part of the book contains the committee's workshop summary and evaluation of ongoing research by Army scientists on immune status in special forces troops, responses to the Army's questions, conclusions, and recommendations. The rest of the book contains papers contributed by workshop speakers, grouped under such broad topics as an introduction to what is known about immune function, the assessment of immune function, the effect of nutrition, and the relation between the many and varied stresses encountered by military personnel and their effect on health.

Do intertidal organisms simply respond to the rise and fall of tides, or do they possess biological timing and navigation mechanisms that allow them to anticipate when conditions are most favourable? How are the patterns of growth, development and reproduction of some marine plants and animals related to changes in day-length or to phases of the moon? The author describes how marine organisms, from single cells to vertebrates, on sea shores, in estuaries and in the open ocean, have evolved inbuilt biological clockwork and synchronisation mechanisms which control rhythmic processes and navigational behaviour, permitting successful exploitation of highly variable and often hostile environments. Adopting a hypothesis-testing and experimental approach, the book is intended for undergraduate and postgraduate students of marine biology, marine ecology, animal behaviour, oceanography and other biological sciences and also as an introduction for researchers, including physiologists, biochemists and molecular biologists entering the field of chronobiology.

J ÜRGEN AscHOFF "Very bad habit! Very bad habit!" Captain Giles to Joseph Conrad who had taken a siesta. -Conrad: The Shadow Line On the Multiplicity of Rest-Activity Cycles: Some Historical and Conceptual Notes According to its title this book tries to answer the profound question of why we nap-and why Captain Giles was wrong in blaming Conrad for having napped. However, in this volume the term nap is not used in the narrower sense of an afternoon siesta; instead, emphasis is placed on the recurrent alternation between states of alertness and drowsiness, i. e. , on rest-activity cycles of high er frequency throughout the 24 hr. In view of this focus, two authors (Stampi, in Chapter I, and Ball, in Chapter 3) rightly refer to the psychologist Szymanski who was among the first to describe "polyphasic" activity patterns. Hence, I consider it appropriate to open this foreword with a few historical remarks. At the time when Szymanski (1920) made the distinction between "monophasic" and "polyphasic" rest-activity patterns and sleep-wake cy cles, respectively, not much was known about the mechanisms of such temporal structures. Although the botanists quite some time ago had demonstrated the endogenous nature of the "monophasic" sleep movements in plants, the hypothesis of an (still unknown) external driving force was favored by those who studied rhythms in animals and humans (Aschoff, 1990).

An introduction to the mathematical, computational, and analytical techniques used for modeling biological rhythms, presenting tools from many disciplines and example applications. All areas of biology and medicine contain rhythms, and these behaviors are best understood through mathematical tools and techniques. This book offers a survey of mathematical, computational, and analytical techniques used for modeling biological rhythms, gathering these methods for the first time in one volume. Drawing on material from such disciplines as mathematical biology, nonlinear dynamics, physics, statistics, and engineering, it presents practical advice and techniques for studying biological rhythms, with a common language. The chapters proceed with increasing mathematical abstraction. Part I, on models, highlights the implicit assumptions and common pitfalls of modeling, and is accessible to readers with basic knowledge of differential equations and linear algebra. Part II, on behaviors, focuses on simpler models, describing common properties of biological rhythms that range from the firing properties of squid giant axon to human circadian rhythms. Part III, on mathematical techniques, guides readers who have specific models or goals in mind. Sections on “frontiers” present the latest research; “theory” sections present interesting mathematical results using more accessible approaches than can be found elsewhere. Each chapter offers exercises. Commented MATLAB code is provided to help readers get practical experience. The book, by an expert in the field, can be used as a textbook for undergraduate courses in mathematical biology or graduate courses in modeling biological rhythms and as a reference for researchers.

The regular alternation of light and dark affects not only human biological systems, but also the social organization of behavior. The effect of such light modes is manifested in periodic changes in physiological functions and biological rhythms exhibited at every level of life. The book discusses some of the specificities of the circadian rhythms in living organisms and mentions aspects of the control of circadian rhythms as well as experimental and clinical cases that are closely related to circadian disruption. This book can evoke interest in many researchers who want to use this information for the advancement of their research towards a better understanding of the biological time structure.