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New Light on Dark Stars: Red Dwarfs, Low-Mass Stars, Brown Dwarfs (Springer Praxis Books)

by Neill I. Reid Suzanne L. Hawley

Perhaps the most common question that a child asks when he or she sees the night sky from a dark site for the first time is: 'How many stars are there?' This happens to be a question which has exercised the intellectual skills of many astronomers over the course of most of the last century, including, for the last two decades, one of the authors of this text. Until recently, the most accurate answer was 'We are not certain, but there is a good chance that almost all of them are M dwarfs. ' Within the last three years, results from new sky-surveys - particularly the first deep surveys at near­ infrared wavelengths - have provided a breakthrough in this subject, solidifying our census of the lowest-mass stars and identifying large numbers of the hitherto almost mythical substellar-mass brown dwarfs. These extremely low-luminosity objects are the central subjects of this book, and the subtitle should be interpreted accordingly. The expression 'low-mass stars' carries a wide range of meanings in the astronomical literature, but is most frequently taken to refer to objects with masses comparable with that of the Sun - F and G dwarfs, and their red giant descendants. While this definition is eminently reasonable for the average extragalactic astronomer, our discussion centres on M dwarfs, with masses of no more than 60% that of the Sun, and extends to 'failed stars' - objects with insufficient mass to ignite central hydrogen fusion.

New Microbiotests for Routine Toxicity Screening and Biomonitoring

by WimCoen ColinJanssen GuidoPersoone

The determination of the hazards resulting from the accidental or deli berate contamination of terrestrial and aquatic environments is in most countries still lirnited to the detection and quantification of the suspected pollutants by chemical analyses. Such an approach is unfortunately hampered by the following constraints : the costs as weil as the technical difficulties of analyzing every individual chemical which may be present in the sampies, and the difficulty of assessing the hazards and risks of environmental contaminations from a set of chemical data. During the last decades the scientific and regulatory community has gradually realized that biological methodologies have to be taken into consideration for an ecologically meaningful assessment of the toxicological hazards of contaminants. Effect evaluations obtained with biological techniques indeed integrate the impact of all the contaminants to which living biota are exposed. Bioassays with selected test species representative for the biological commumtles of the environments under consideration, are now applied more or less regularly to determine toxic and genotoxic effects. Taking into account the species specific and chemical specific character of toxicity to biota, the necessity of a «battery of tests» approach with species of different trophic levels is currently also generally accepted and implemented. It is dear that a balanced partnership between chemical, biological, toxicological and microbiological analyses is always the best strategy for generating the broadest information base on environmental hazards.

New Trends in Quantum Structures (Mathematics and Its Applications #516)

by Anatolij Dvurecenskij Sylvia Pulmannová

D. Hilbert, in his famous program, formulated many open mathematical problems which were stimulating for the development of mathematics and a fruitful source of very deep and fundamental ideas. During the whole 20th century, mathematicians and specialists in other fields have been solving problems which can be traced back to Hilbert's program, and today there are many basic results stimulated by this program. It is sure that even at the beginning of the third millennium, mathematicians will still have much to do. One of his most interesting ideas, lying between mathematics and physics, is his sixth problem: To find a few physical axioms which, similar to the axioms of geometry, can describe a theory for a class of physical events that is as large as possible. We try to present some ideas inspired by Hilbert's sixth problem and give some partial results which may contribute to its solution. In the Thirties the situation in both physics and mathematics was very interesting. A.N. Kolmogorov published his fundamental work Grundbegriffe der Wahrschein­ lichkeitsrechnung in which he, for the first time, axiomatized modern probability theory. From the mathematical point of view, in Kolmogorov's model, the set L of ex­ perimentally verifiable events forms a Boolean a-algebra and, by the Loomis-Sikorski theorem, roughly speaking can be represented by a a-algebra S of subsets of some non-void set n.

New Types of Persistent Halogenated Compounds (The Handbook of Environmental Chemistry #3 / 3K)

by Jaakko Paasivirta

Environmental Chemistry is a relatively young science. Interest in this subject, however, is growing very rapidly and, although no agreement has been reached as yet about the exact content and limits of this interdisciplinary discipline, there appears to be increasing interest in seeing environmental topics which are based on chemistry embodied in this subject. One of the first objectives of Environ mental Chemistry must be the study of the environment and of natural chemical processes which occur in the environment. A major purpose of this series on Environmental Chemistry, therefore, is to present a reasonably uniform view of various aspects of the chemistry of the environment and chemical reactions occurring in the environment. The industrial activities of man have given a new dimension to Environ mental Chemistry. We have now synthesized and described over five million chemical compounds and chemical industry produces about hundred and fifty million tons of synthetic chemicals annually. We ship billions of tons of oil per year and through mining operations and other geophysical modifications, large quantities of inorganic and organic materials are released from their natural deposits. Cities and metropolitan areas of up to 15 million inhabitants produce large quantities of waste in relatively small and confined areas. Much of the chemical products and waste products of modern society are released into the environment either during production, storage, transport, use or ultimate disposal. These released materials participate in natural cycles and reactions and frequently lead to interference and disturbance of natural systems.

NIELS HENRIK ABEL and his Times: Called Too Soon by Flames Afar

by Arild Stubhaug

Everyone with an interest in the history of mathematics and science will enjoy reading this book on one of the most famous mathematicians of the 19th century. The author, who is both a historian and a mathematician, has written the definitive biography of Niels Henrik Abel.

The Night Sky: An astronomers guide to the night sky and the universe (Usborne Spotter's Guides)

by Nigel Henbest

Discover the wonders of the Universe with this indispensable guide. The Night Sky is chock full of information explaining what, when and how to observe space and understanding the night sky.Not only accessible, but also invaluable, this is the perfect practical guide for both budding and seasoned astronomers, an easy introduction to astronomy and a useful resource for more experienced stargazers.

Nineteenth-Century Media and the Construction of Identities

by Laurel Brake B. Bell D. Finkelstein

This collection of important new research in 19th-century media history represents some salient, recent developments in the field. Taking as its theme, the ways the media serves to define identities - national, ethnic, professional, gender, and textual, the volume addresses serials in the UK, the US, and Australia. High culture rubs shoulders with the popular press, text with image, feminist periodicals and masculine, gay, and domestic serials. Theory and history combine in research by scholars of international repute.

Nitric Oxide (Handbook of Experimental Pharmacology #143)

by B. Mayer

Nitric oxide (NO) has been discovered to play a fundamental role in a number of biological phenomena. This book describes various aspects of nitric oxide biology, physiology and pharmacology. It is divided into three sections. The first part deals with the basic chemistry and enzymology of NO, thus laying a molecular basis for what follows. The middle part surveys the physiological roles of NO under normal conditions. The concluding part explores the relevance of NO to disease, both as a pathogenic factor and a therapeutic target. The book thus provides detailed information on NO biology to the reader unfamiliar with the field and represents a reference work for scientists working in an NO-related field of biomedical research. Each chapter, written by experts in their fields, gives a broad introduction followed by a comprehensive review of the current knowledge and a detailed reference list.

Nitric Oxide and Free Radicals in Peripheral Neurotransmission (Nitric Oxide in Biology and Medicine #2)

by Jack R. Lancaster

"Nitric Oxide and Free Radicals in Peripheral Neurotransmission" is a welcome addition to the literature and describes current research into the role of nitric oxide in the peripheral nervous system and its associated organs. Topics covered range from general consideration of nitrergic transmission, in its broadest sense, to elaboration of our current understanding of the role of nitric oxide in transmission in individual peripheral organs, including its role as a backup, or alternate as well as chief transmitter. The influence of nitric oxide and related compounds on the more conventional modes of autonomic transmission are also considered. Aimed at students and researchers in the areas of neuroscience and physiology, "Nitric Oxide and Free Radicals in Peripheral Neurotransmission" also covers the emerging role of abnormal nitric oxide function in disease states and, where appropriate, as potential avenues of therapy.

Nitric Oxide in Plants: Occurrence, Function and Use

by Y.Y. Leshem

This book - the first published on this topic in plants - presents the reader with an overview of recent research on nitric oxide (NO) in plants, which, in view of its empirical interest and its growth regulatory potential, is in the forefront of scientific endeavor in plant science. Subject matter is divided into two parts: Part 1 deals with NO and peroxynitrite biochemistry and regulative mechanisms as presently known in the Plant Kingdom and outlines some of the problems still awaiting clarification. Emphasis is placed on ethylene emission regulation, postharvest control, plant phytopathology and environmental stress tolerance. A further topic is plant NO, like Viagra, related to cyclic nucleotide turnover. Part 2 deals with environmental aspects of NO as an atmospheric pollutant and discusses endogenous means which plants at times employ to cope with this particular type of stress, and how their coping mechanisms may be harnessed for purposes of depollution and augmentation of nitrogen fertilization. The text, accompanied by a wealth of illustrations and annotated references, is intended for lecturers, advanced students and research scientists at universities and research institutes dealing with plant sciences and agriculture, as well as for environmental researchers.

Nitrogen Fixation: Proceedings of the 12th International Congress on Nitrogen Fixation, Foz do Iguaçu, Paraná, Brazil, September 12–17, 1999 (Current Plant Science and Biotechnology in Agriculture #38)

by Mariangela Hungria William E. Newton Fabio O. Pedrosa Geoffrey Yates

These proceedings bring together diverse disciplines that study nitrogen fixation and describe the most recent advances made in various fields: chemists are now studying FeMoco, the active site of nitrogenase in non-protein surroundings, and have refined the crystal structure of the enzyme to 1.6 angstroms.

Noise, Oscillators and Algebraic Randomness: From Noise in Communication Systems to Number Theory (Lecture Notes in Physics #550)

by Michel Planat

Noise is ubiquitous in nature and in man-made systems. Noise in oscillators perturbs high-technology devices such as time standards or digital communication systems. The understanding of its algebraic structure is thus of vital importance. The book addresses both the measurement methods and the understanding of quantum, 1/f and phase noise in systems such as electronic amplifiers, oscillators and receivers, trapped ions, cosmic ray showers and in commercial applications. A strong link between 1/f noise and number theory is emphasized. The twenty papers in the book are comprehensive versions of talks presented at a school in Chapelle des Bois (Jura, France) held from April 6 to 10, 1999, by engineers, physisicts and mathematicians.

Non-CO2 Greenhouse Gases: Proceedings of the Second International Symposium, Noordwijkerhout, The Netherlands, 8–10 September 1999

by J. Van Ham A. P. M. Baede L. A. Meyer R. Ybema

In the climate change discussion, non-CO2 greenhouse gases (NCGGs) received official political recognition for the first time in 1997, when agreement was reached on the Kyoto Protocol. As a result methane, nitrous oxide, HFCs, PFCs and SF6 now provide attractive options for detailing the national targets for the reduction of greenhouse gas emissions meant to control climate change. This book is the second volume in this area and addresses three main topics. Firstly, it documents progress with respect to our knowledge of the sources and sinks of NCGGs. Information on this subject is essential in order to reduce the uncertainties in national emissions inventories which serve as the reference values for commitments of countries in the framework of the Kyoto Protocol. Secondly, this volume deals with the control options for the NCGGs and contains a wealth of information in this area. Emerging technologies here provide business opportunities, in particular in connection with the flexible mechanisms for mitigation projects in developing countries which have been agreed in Kyoto. Thirdly, the book treats the policy implementation of mitigation options for greenhouse gas emissions. Tools for control policies, both on the national and international level, and for different sectors of industry are discussed. National integrated approaches, including the ones from the United States Environmental Protection Agency and the Netherlands Ministry of Environment which both sponsored the conference, provide guidance for defining the most effective greenhouse gases mitigation plans in different situations. This volume is being published in support of the IPCC Process and will serve as a reference for IPCC's Third Assessment Report.

Non-Crystalline Chalcogenicides (Solid-State Science and Technology Library #8)

by M.A. Popescu

The earliest experimental data on an oxygen-free glass have been published by Schulz-Sellack in 1870 [1]. Later on, in 1902, Wood [2], as well as Meier in 1910 [3], carried out the first researches on the optical properties of vitreous selenium. The interest in the glasses that exhibit transparency in the infrared region of the optical spectrum rose at the beginning of the twentieth century. Firstly were investigated the heavy metal oxides and the transparency limit was extended from (the case of the classical oxide glasses) up to wavelength. In order to extend this limit above the scientists tried the chemical compositions based on the elements of the sixth group of the Periodic Table, the chalcogens: sulphur, selenium and tellurium. The systematic research in the field of glasses based on chalcogens, called chalcogenide glasses, started at the middle of our century. In 1950 Frerichs [4] investigated the glass and published the paper: “New optical glasses transparent in infrared up to 12 . Several years later he started the study of the selenium glass and prepared several binary glasses with sulphur [5]. Glaze and co-workers [6] developed in 1957 the first method for the preparation of the glass at the industrial scale, while Winter-Klein [7] published reports on numerous chalcogenides prepared in the vitreous state.

Non-Parametric Statistical Diagnosis: Problems and Methods (Mathematics and Its Applications #509)

by E. Brodsky B.S. Darkhovsky

Non-Parametric Statistical Diagnosis

Nonculturable Microorganisms in the Environment

by Colwell

Nonlinear Continuum Mechanics of Solids: Fundamental Mathematical and Physical Concepts

by Yavuz Basar Dieter Weichert

The aim of the book is the presentation of the fundamental mathematical and physical concepts of continuum mechanics of solids in a unified description so as to bring young researchers rapidly close to their research area. Accordingly, emphasis is given to concepts of permanent interest, and details of minor importance are omitted. The formulation is achieved systematically in absolute tensor notation, which is almost exclusively used in modern literature. This mathematical tool is presented such that study of the book is possible without permanent reference to other works.

Nonlinear Model-based Process Control: Applications in Petroleum Refining (Advances in Industrial Control)

by Rashid M. Ansari Moses O. Tade

The series Advances in Industrial Control aims to report and encourage technology transfer in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. New theory, new controllers, actuators, sensors, new industrial processes, computer methods, new applications, new philosophies ... , new challenges. Much of this development work resides in industrial reports, feasibility study papers and the reports of advanced collaborative projects. The series offers an opportunity for researchers to present an extended exposition of such new work in all aspects of industrial control for wider and rapid dissemination. The last decade has seen considerable interest in reviving the fortunes of non­ linear control. In contrast to the approaches of the 60S, 70S and 80S a very pragmatic agenda for non-linear control is being pursued using the model-based predictive control paradigm. This text by R. Ansari and M. Tade gives an excellent synthesis of this new direction. Two strengths emphasized by the text are: (i) four applications found in refinery processes are used to give the text a firm practical continuity; (ii) a non-linear model-based control architecture is used to give the method a coherent theoretical framework.

Nonlinear Model Predictive Control (Progress in Systems and Control Theory #26)

by Frank Allgöwer Alex Zheng

During the past decade model predictive control (MPC), also referred to as receding horizon control or moving horizon control, has become the preferred control strategy for quite a number of industrial processes. There have been many significant advances in this area over the past years, one of the most important ones being its extension to nonlinear systems. This book gives an up-to-date assessment of the current state of the art in the new field of nonlinear model predictive control (NMPC). The main topic areas that appear to be of central importance for NMPC are covered, namely receding horizon control theory, modeling for NMPC, computational aspects of on-line optimization and application issues. The book consists of selected papers presented at the International Symposium on Nonlinear Model Predictive Control – Assessment and Future Directions, which took place from June 3 to 5, 1998, in Ascona, Switzerland.The book is geared towards researchers and practitioners in the area of control engineering and control theory. It is also suited for postgraduate students as the book contains several overview articles that give a tutorial introduction into the various aspects of nonlinear model predictive control, including systems theory, computations, modeling and applications.

Nonlinear Optical Effects and Materials (Springer Series in Optical Sciences #72)

by Peter Günter

Describing progress achieved in the field of nonlinear optics and nonlinear optical materials, the Handbook treats selected topics such as photorefractive materials, third-order nonlinear optical materials and organic nonlinear optical crystals, as well as electro-optic polymers. Applications of photorefractive materials in optical memories, optical processing, and guided-wave nonlinear optics in hotorefractive waveguides are described. As light will play a more and more dominant role as an information carrier, the review of existing and new materials given here makes this a keystone book in the field.

Nonlinear Optics of Random Media: Fractal Composites and Metal-Dielectric Films (Springer Tracts in Modern Physics #158)

by Vladimir M. Shalaev

Nonlinear Optics of Random Media reviews recent advances in in one of the most prominent fields of physics. It provides an outline of the basic models of irregular structures of random inhomogeneous media and the approaches used to describe their linear electromagnetic properties. Nonlinearities in random media are also discussed. The chapters can be read independently, so scientists and students interested in a specific problem can go directly to the relevant text.

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