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Dendritic Cells: Methods and Protocols (Methods in Molecular Biology #2618)

by Vanja Sisirak

This detailed volume provides methods that can be used to study dendritic cell (DC) ontogeny, isolation, migration, and functions. After an introduction to murine and human DC subsets and their unique transcriptional, phenotypic, and functional properties, the book continues with sections covering in vivo studies, in vitro differentiation, enrichment, functional characterization, as well as Omics approaches to study dendritic cells. Written for the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Dendritic Cells: Methods and Protocols is an ideal guide to familiarize readers with the current state of the art techniques to investigate these vital cells.

Dendritic Cells and Virus Infection (Current Topics in Microbiology and Immunology #276)

by Prof. Dr. Alexander Steinkasserer

Dendritic cells are vital to induce potent anti-viral immune responses. It will become clear to the reader that dendritic cells often play a dual role during viral infections. On the one hand they are able to mount potent antiviral immune responses, and on the other hand several viruses, including HIV-1, use DC as a vector to be transferred from the periphery to the lymph nodes where they infect their prime target.

Dendritic Cells: Biophysics, Tumor Microenvironment and Chinese Traditional Medicine (SpringerBriefs in Biochemistry and Molecular Biology)

by Zhu Zeng Xiaofeng Xu Dan Chen

In this book, the authors discuss the biophysical characteristics of Dendritic cells (DCs) at various differentiation stages and in tumor microenvironments in detail. A type of Chinese traditional herb, which can improve the biophysical and microrheological properties of DCs, is also introduced. DCs are potent and specialized antigen-presenting cells that play a crucial role in initiating and amplifying both the innate and adaptive immune responses. The biophysical and microrheological characteristics of DCs are important for their motility and normal immune function. In tumor microenvironments, the motility and immune functions of DCs are impaired, but the mechanisms are largely unknown. This book offers researchers a comprehensive and deep insight into the biophysical characteristics of DCs and may also help to improve the efficiency of anti-tumor therapy based on DCs.

Dendritic Cells in Cancer

by Russell D. Salter Michael R. Shurin

It covers all aspects of DC generation, function, survival and antitumor activity in the tumor environment both in vivo and in experimental in vitro systems. The goal in focusing on a spectrum of issues related to DC in cancer is to provide an extensive and expansive review rather than a collection of independent analyses from different authors. Specific topics to be covered include analysis of DC behavior in the tumor microenvironment, including endogenous and exogenous DC, multiple DC populations, molecular pathways responsible for DC dysfunction, tumor-derived factors altering DC polarization and activation, mechanisms of DC alterations, and the role of DC in tumor escape from immune recognition and elimination. Furthermore, additional chapters provide extensive analysis of the consequences of cancer therapy on the DC system and how aging impacts DC function in the tumor microenvironment. Finally, chapters are included examining strengths and pitfalls of current methodologies for generating DC from cancer patients for therapeutic purposes and on the role of tumor-mediated modulation of the DC system in cancer immunotherapy.

Dendritic Cells in Clinics

by Morikazu Onji Sk. Md. Akbar

Great advances have taken place in basic research and the clinical usefulness of dendritic cells (DCs). It has now been clearly established, for instance, that these cells play a crucial role in immune responses against infectious diseases and cancers. Antigen-presenting DCs are widely distributed in the body and regulate both immunity and immune tolerance. Experimental studies have provided important insights into DCs and how they can be used for treating animal models of various diseases that occur in humans. The role of these cells in pathogenesis and the treatment of human diseases is elaborately set forth in this valuable book. Researchers in the field are optimistic that DCs, already in use for treating patients with cancers, soon can be used therapeutically for patients with chronic infections, autoimmune diseases, and allergic manifestations. This volume provides a working definition of DCs and also explains the phenotypes and functions of DCs so that these can be readily understood not only by clinicians but by immunologists, researchers, and students as well.

Dendritic Cells in Clinics

by Morikazu Onji Sk. Md. Akbar

Great advances have taken place in basic research and the clinical usefulness of dendritic cells (DCs). It has now been clearly established, for instance, that these cells play a crucial role in immune responses against infectious diseases and cancers. Antigen-presenting DCs are widely distributed in the body and regulate both immunity and immune tolerance. Experimental studies have provided important insights into DCs and how they can be used for treating animal models of various diseases that occur in humans. The role of these cells in pathogenesis and the treatment of human diseases is elaborately set forth in this valuable book. Researchers in the field are optimistic that DCs, already in use for treating patients with cancers, soon can be used therapeutically for patients with chronic infections, autoimmune diseases, and allergic manifestations. This volume provides a working definition of DCs and also explains the phenotypes and functions of DCs so that these can be readily understood not only by clinicians but by immunologists, researchers, and students as well.

Dendritic Cells in Fundamental and Clinical Immunology: Volume 2 (Advances in Experimental Medicine and Biology #378)

by Jacques Banchereau Daniel Schmitt

These Proceedings contain the contributions of the partIcIpants of the Third International Symposium on Dendritic Cells that was held in Annecy, France, from June 19 to June 24, 1994. This symposium represented a follow-up of the first and second international symposia that were held in Japan in 1990 and in the Netherlands in 1992. Dendritic cells are antigen-presenting cells, and are found in all tissues and organs of the body. They can be classified into: (1) interstitial dendritic cells of the heart, kidney, gut, and lung;(2) Langerhans cells in the skin and mucous membranes; (3) interdigitating dendritic cells in the thymic medulla and secondary lymphoid tissue; and (4) blood dendritic cells and lymph dendritic cells (veiled cells). Although dendritic cells in each of these compartments are all CD45+ leukocytes that arise from the bone marrow, they may exhibit differences that relate to maturation state and microenvironment. Dendritic cells are specialized antigen-presenting cells for T lymphocytes: they process and present antigens efficiently in situ, and stimulate responses from naive and memory T cells in the paracortical area of secondary lymphoid organs. Recent evidence also demonstrates their role in induction of tolerance. By contrast, the primary and secondary B-cell follicles contain follicular dendritic cells that trap and retain intact antigen as immune complexes for long periods of time. The origin of follicular dendritic cells is not clear, but most investigators believe that these cells are not leukocytes.

Dendritic Cells in Fundamental and Clinical Immunology (Advances in Experimental Medicine and Biology #329)

by Paul Nieuwenhuis Eduard W. A. Kamperdijk Elizabeth C. M. Hoefsmit

These Proceedings contain the contributions of the participants of the Second International Symposium on Dendritic Cells that was held from the 1st to 25th of June 1992 in Amsterdam, the Netherlands. The First International Symposium on Dendritic Cells was organized as a Satellite symposium at the occasion of the 30th anniversary of the Japanese Reticuloendothelial Society by Dr. Y. Imai in Yamagata (Japan), in 1990. It was entitled "Dendritic Cells in Lymphoid Tissues," and focused primarily on the Interdigitating Cells (IDC), Epidermal Langerhans cells (LC) and Follicular Dendritic Cells (FDC) , from the point of view of human pathology. However, the concept of Dendritic Cell System, comprising the bone marrow derived IDC and LC but not the FDC, was based on animal experiments and mainly on in vitro experiments on isolated cells. In a report from the Reticuloendothelial Society Committee on Nomenclature in 1982, Tew, Thorbecke and Steinman had already characterized these different types of DC, but the gap between in vivo and in vitro function remained. In Amsterdam, the Symposium focused on the Role of Dendritic Cells in Fundamental and Clinical Immunology. First, recent developments in molecular biology of antigen presentation and cell biological aspects of signal transduction were discussed, in relation to the potential of DC to stimulate lymphocytes and to trigger their in vitro differentiation.

Dendritic Cells in Fundamental and Clinical Immunology: Volume 3 (Advances in Experimental Medicine and Biology #417)

by Paola Ricciardi-Castagnoli

These proceedings contain selected contributions from the participants to the Fourth International Symposium on Dendritic cells that was held in Venice (Lido) Italy, from Oc­ tober 5 to 10, 1996. The symposium was attended by more than 500 scientists coming from 24 different countries. Studies on dendritic cells (DC) have been greatly hampered by the difficulties in preparing sufficient cell numbers and in a reasonable pure form. At this meeting it has been shown that large quantities of DC can be generated from precursors in both mice and humans, and this possibility has enormously encouraged studies aimed to characterize DC physiology and DC-specific genes, and to employ DC therapeutically as adjuvants for im­ munization. The possibility of generating large numbers of autologous DC that can be used in the manipulation of the immune response against cancer and infectious diseases has tremendously boosted dendritic cell research and the role of DC in a number of medi­ cal areas has been heatedly discussed.

Dendritic Neurotransmitter Release

by Mike Ludwig

The transmission of the nervous impulse is always from the dendritic branches and the cell body to the axon or functional process. Every neuron, then, possesses a receptor apparatus, the body and the dendritic prolongations, an apparatus of emission, the axon, and the apparatus of distribution, the terminal arborization of the nerve fibers. I designated the foregoing principle: the theory of dynamic polarization (Cajal 1923). Ever since the beautiful drawings from Golgi and Cajal, we have been familiar with the organisation of neurones into dendritic, somatic and axonal compartments. Cajal proposed that these cellular compartments were specialised, resulting in his concept of ^dynamic polarisation'. He considered dendrites to be passive elements that simply transferred information from inputs to the soma. Since the discovery that dendrites of many neural populations release neuroactive substances and in doing so, alter neuronal output, it is now apparent that this theory requires qualification. This book presents recent developments in the neurophysiology of dendritic release of several chemical classes of transmitters in a number of different areas of the mammalian central nervous system. Once released from a neuron, these substances can act as neurotransmitters and/or neuromodulators, to autoregulate the original neuron, its synaptic inputs, and adjacent cells or, by volume transmission, to affect distant cells. In some systems, dendritic transmitter release is part independent of secretion from axon terminal signifying a selective control of the dendritic compartment.

Dendritic Spines: Structure, Function, and Plasticity (Advances in Neurobiology #34)

by Alberto A. Rasia-Filho Maria Elisa Calcagnotto Oliver von Bohlen und Halbach

This reference provides detailed coverage of dendritic spines, the fascinating neuronal components that modulate synaptic transmission, development, strength, and plasticity and are involved in the function of multiple areas of the nervous system. The density, shape, and function of spines may indicate the cellular connectivity and synaptic plasticity in normal and pathological conditions. This field has undergone dramatic advances in terms of techniques and experimental findings from in vitro to in vivo data, from animal models to human neurons, and computational models using artificial intelligence. To address these cutting-edge findings, the book provides state-of-the-art, comprehensive coverage with chapters written by the leading international researchers in the field. The authors consider the multiple implications for the study of dendritic spines with broad implications in the neurosciences and related areas.

The Denervated Muscle: (pdf)

by Ernest Gutmann

Dengue: Methods and Protocols (Methods in Molecular Biology #1138)

by Radhakrishnan Padmanabhan and Subhash G. Vasudevan

Infection by flaviviruses such as dengue virus serotypes (DENV 1-4), Japanese encephalitis virus (JEV), tick-borne encephalitis virus (TBE), yellow fever virus (YFV) and West Nile virus (WNV) impact millions of lives and cause tens of thousands of mortalities each year. Dengue is a global public health emergency especially since there is no preventative vaccine or antiviral treatment for dengue disease. Dengue: Methods and Protocols offers the increasing number of dengue researchers a one-stop protocol book with techniques compiled from the leading laboratories working on dengue. Chapters cover topics such as dengue virus isolation from clinical samples, quantification of human antibodies against the virus, assays to quantify the virus particles, the widely used mouse model to study dengue pathogenesis, vaccine and antiviral efficacies. Written in the successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible protocols and notes on troubleshooting and avoiding known pitfalls.Authoritative and easily accessible, Dengue: Methods and Protocols seeks to serve both professionals and novices with its well-honed methodologies on dengue research.

Dengue and Dengue Hemorrhagic Fever

by Ana Fernandez-Sesma Paul Paul Katherine L Katherine L Nicholas Nicholas Shannon Shannon Katell Katell Shelton S Shelton S Oliver Oliver David M David M Philippe Philippe Michael D Michael D Laura A Laura A Keith J Keith J Christopher M Christopher M Derek A Derek A T Aravinda M Aravinda M Michael S Michael S George George T T Delia Delia Francesca D Francesca D Andrea V Andrea V Mariano A Mariano A Adolfo Adolfo Maria G Maria G Yara A Yara A

Continued geographic expansion of dengue viruses and their mosquito vectors has seen the magnitude and frequency of epidemic dengue/dengue hemorrhagic fever (DF/DHF) increase dramatically. Recent exciting research on dengue has resulted in major advances in our understanding of all aspects of the biology of these viruses, and this updated second edition brings together leading research and clinical scientists to review dengue virus biology, epidemiology, entomology, therapeutics, vaccinology and clinical management.

Dengue and Zika: Control and Antiviral Treatment Strategies (Advances in Experimental Medicine and Biology #1062)

by Rolf Hilgenfeld Subhash G. Vasudevan

This contributed volume contains 25 chapters from leading international scientists working on dengue and Zika viruses, who came together in Praia do Tofo in Mozambique to discuss the latest developments in the fields of epidemiology, pathogenesis, structural virology, immunology, antiviral drug discovery and development, vaccine efficacy, and mosquito control programs. The meeting venue offered an opportunity to discuss current research on these flaviviruses in an idyllic setting, and also to develop first-hand appreciation of the issues in infectious diseases facing developing countries and of the research gaps in Africa. For readers, who should include basic and clinical researchers in the field and public health professionals, the chapters are organized to provide a comprehensive overview of the various topics in current dengue and Zika virus research. A unique feature of the proceedings of this meeting is the inclusion of the discussions that took place following presentations. These have been transcribed and appended to the end of the relevant chapters, and they form the “salt in the soup” of this book.

Dengue Diagnostics: The Right Test at the Right Time for the Right Group

by Shamala Devi Sekaran

Diagnostics plays a vital role in identifying infectious diseases that have the potential to become an epidemic, such as dengue. Good diagnostics enables identifying the cause of an outbreak and assessing interventions for a better impact. The dengue virus is a member of the family of flaviviruses that cross-reacts serologically with all members of its family. The presenting symptoms do not allow definitive diagnosis because they can be of malaria, dengue, Zika, chikungunya, or one of a host of other possibilities. In children, efficient and accurate dengue diagnostics is very important for the early confirmation of dengue because of its quick progress to severe dengue. Dengue diagnostic assays are wide-ranging—from being a reliable one that is time-consuming and expensive to rapid test kits that substantially vary in their accuracy. Therefore, it is important to know which test is to be used at what time, considering whether the population is in an endemic area, as well as how and when to use these tests, be it for the virus or for its genome, antigens, or antibodies. An ideal diagnostic test is one that can pick the virus early enough, is rapid and easy to perform, and affordable by all communities but such a test is yet not available. This book deals with most of the methods that have been used or developed for diagnosing dengue. It addresses the timeline for the evolution of the virus in the body, the body’s response from the onset of fever, and the role of diagnostics as time progresses. It covers most methods, detailing selected protocols, as well as compares them and assesses the time point at which they are useful. The book will be helpful in determining the right test, at the right time, for the right population.

Dengue Diagnostics: The Right Test at the Right Time for the Right Group

by Shamala Devi Sekaran

Diagnostics plays a vital role in identifying infectious diseases that have the potential to become an epidemic, such as dengue. Good diagnostics enables identifying the cause of an outbreak and assessing interventions for a better impact. The dengue virus is a member of the family of flaviviruses that cross-reacts serologically with all members of its family. The presenting symptoms do not allow definitive diagnosis because they can be of malaria, dengue, Zika, chikungunya, or one of a host of other possibilities. In children, efficient and accurate dengue diagnostics is very important for the early confirmation of dengue because of its quick progress to severe dengue. Dengue diagnostic assays are wide-ranging—from being a reliable one that is time-consuming and expensive to rapid test kits that substantially vary in their accuracy. Therefore, it is important to know which test is to be used at what time, considering whether the population is in an endemic area, as well as how and when to use these tests, be it for the virus or for its genome, antigens, or antibodies. An ideal diagnostic test is one that can pick the virus early enough, is rapid and easy to perform, and affordable by all communities but such a test is yet not available. This book deals with most of the methods that have been used or developed for diagnosing dengue. It addresses the timeline for the evolution of the virus in the body, the body’s response from the onset of fever, and the role of diagnostics as time progresses. It covers most methods, detailing selected protocols, as well as compares them and assesses the time point at which they are useful. The book will be helpful in determining the right test, at the right time, for the right population.

Dengue Haemorrhagic Fever in Thailand: Geomedical Observations on Developments Over the Period 1970–1979 (Sitzungsberichte der Heidelberger Akademie der Wissenschaften #1983 / 1983)

by Hella Wellmer

On the occasion of a research visit to Thailand in my capacity as a member of the governing board of the South Asia Institute of the University of Heidelberg, I saw for the first time the severe clinical picture of dengue with haemorrhagic symptoms among Thai children. This visit had been made possible by Profes­ sor Dr. med. Dr. rer. nat. Ouay Ketusinh of Bangkok, to whom I wish to express my sincere thanks in this place. In 1972 the German medical literature - the periodical Medizinische Klinik, vol. 87, pp. 152-56, to be precise - had drawn attention to this new phenomenon in the disease panorama of South East Asia, indicating a change in dengue fever from being a relatively benign tropical dis­ ease to a form having serious clinical and epidemiological ramifications. During the ten years following my first publication the new clinical picture, described as "dengue haemorrhagic fever", has become a standard component in the Thailand's system of notifiable diseases. So too, the World Health Orga­ nization publishes regular reports in its Weekly Records. On March 30/31, 1981, its Regional Office for South East Asia convened a special conference in New Delhi, thus emphasizing the significance of the diffusion of this new clini­ cal picture in the states of South East Asia.

Dengue Virus: Methods and Protocols (Methods in Molecular Biology #2409)

by Ronaldo Mohana-Borges

This detailed volume explores various aspects of the dengue virus and its four serotypes (DENV1-4). Beginning with a section on protocols to produce DENV and its proteins that are fundamental for many biophysical, biochemical, immunological, and cellular studies, the book continues by covering protocols to study the interactions between DENV and cellular proteins, DENV immunopathogenesis and diagnosis, as well as recent advances in animal models that can be used in studies of DENV immunopathogenesis and vaccine development. Written for the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Dengue Virus: Methods and Protocols serves as an ideal guide for researchers attempting to further understand this critical threat to worldwide public health.

Dengue Virus (Current Topics in Microbiology and Immunology #338)

by Alan L. Rothman

Scientific research on dengue has a long and rich history. The literature has been touched by famous names in medicine- Benjamin Rush, Walter Reed, and Albert Sabin, to name a very few- and has been fertile ground for medical historians . The advances made in those early investigations are all the more remarkable for the limited tools available at the time. The demonstration of a viral etiology for dengue fever, the recognition of mosquitoes as the vector for transmission to humans, and the existence of multiple viral variants (serotypes) with only partial cross-protection were all accomplished prior to the ability to culture and characterize the etiologic agent. Research on dengue in this period was typically driven by circumstances. Epidemics of dengue created public health crises, although these were relatively short-lived in any one location, as the population of susceptible individuals quickly shrank. Military considerations became as a major driving force for research. With the introduction of large numbers of non-immune individuals into endemic areas, dengue could cripple military readiness, taking more soldiers out of action than hostile fire. Dengue and dengue hemorrhagic fever, which assumed pandemic proportions during the latter half of the last century, have shown no indication of slowing their growth during this first decade of the twenty-first century. Challenges remain in understanding the basic mechanisms of viral replication and disease pathogenesis, in clinical management of patients, and in control of dengue viral transmission. Nevertheless, new tools and insights have led to major recent scientific advances. As the first candidate vaccines enter large-scale efficacy trials, there is reason to hope that we may soon "turn the corner" on this disease.

Dengue Viruses (Virology Monographs Die Virusforschung in Einzeldarstellungen #16)

by R.W. Schlesinger

2. Virological Findings. 90 3. Immunity. . . . . 90 C. Secondary Dengue: Dengue Hemorrhagic Fever and the Shock Syndrome 92 1. General Remarks. . . . . . . . . . . . . . 92 2. Clinical Course and Clinical Laboratory Findings 93 3. Virological and Serological Findings. . . 95 4. Immunopathology of Secondary Dengue. 98 XI. Immunization. . . . . . . . . . . . . . . 104 A. Anamnestic Immune Responses in Sequential Infections With Dengue and Other Group B Togaviruses . . . . . . . . 104 1. Results With Members of the Dengue Subgroup 104 2. Results With Dengue and Other Flaviviruses. 107 B. Dengue Vaccines for Use in Man 108 XII. Opportunities for the Future 113 Acknowledgments. 114 References. . . . . . . . . . . 114 I. Introduction Dengue fever is a mosquito-transmitted disease of man which has afflicted untold millions of people over the past two centuries. It is caused by viruses classified as a subgroup of the group B togaviruses. Along with other members of that group as well as group A, the dengue viruses have been investigated intensively during recent years. Certain unique aspects of their structure, composition, antigenicity, replication, and antigenic relationships have established the togavirus family as quite distinct from other families of enveloped RNA viruses (see recent review of PFEFFERKORN and SHAPIRO, 1974). The basic studies leading to this conclusion have coincided with epidemiological field investigations which have resulted in a continuing increase in the number of viruses now designated as group A or B togaviruses. This, in turn, has led to a growing appreciation of their immense importance as actual or potential pathogens of man and beast.

Denial: A Clarification of Concepts and Research

by E. L. Edelstein D. L. Nathanson A. M. Stone

We do not think about everything at once all the time. Various mecha­ nisms allow us to choose from among the themes, issues, topics, feelings, ideas, and memories that might occupy consciousness. One can focus selectively on anything deemed important; yet the methods by which this is accomplished vary greatly. We clinicians assign to these various mech­ anisms names that fit whatever theoretical system is central to our work-the healthy suppression of "background noise" allows us to pay attention to certain matters; the repression of unconscious conflict may assist our functioning in one moment despite its later cost; whereas denial and disavowal are used as general and fairly nonspecific terms for matters that are left out of awareness in order to avoid the noxious emotions specific to the personal significance of such awareness. Despite the attitude of scientific objectivity characterizing Freud's introduction of psychoanalysis, an aura of morality clings to certain of these mecha­ nisms, for we tend to judge people by their use of them. We are a society of doers, people of action and accomplishment who look with disrespect at the avoidance of any responsibility or task. Thus denial has taken on a negative connotation, and those who use this avoidance system are seen as the lesser among us.

Denis Burkitt: A Cancer, the Virus, and the Prevention of Man-Made Diseases (Springer Biographies)

by John H. Cummings

This biography of Dr. Denis Parsons Burkitt, after whom the childhood cancer Burkitt's lymphoma was named, and who was a pioneer of the dietary fiber movement, paints a personal but holistic portrait of both the man and his life's work. Featuring excerpts from Dr. Burkitt's personal diaries, spanning seven decades from his boyhood to just before his passing, and extensive family archives, this book invites readers to follow Burkitt's journey through life and experience his tribulations and successes. Prof. John Cummings was a colleague of Dr. Burkitt and weaves the tale of his life through the lens of family, faith, and science. The journey takes Burkitt from his childhood in Ireland, a country undergoing major social upheaval, through his medical studies in Dublin, to army service in Africa in the midst of WWII and the independence movements that swept the continent in the following years. During his two decades spent in Uganda, working for the Colonial Medical Service, Burkitt made his first major contribution to cancer research - the characterization of Burkitt's lymphoma and its possible viral cause. Following his return to England in 1966, he turned his attention to the cause of ‘Western Diseases’ especially the role of dietary fibre in the prevention of disease and promotion of health. This earned him even wider international recognition and helped to inspire what is a vital field of research today. The book examines Burkitt's personal views of the world around him, including his experiences as a committed evangelical Christian who had been raised an Irish Protestant, and the challenges, both familial and cultural, that this elicited from and towards him and his scientific work. The lymphoma and later the fibre story propelled Denis into an orbit of worldwide travel, fame and many honours. An engaging speaker but man of great humility, always giving the credit for much of what he did to others, he left a legacy of evidence and ideas for the causes of cancer and prevention of disease from which we all now benefit.

Denitrification in Soil and Sediment (F.E.M.S. Symposium Series #56)

by Niels Peter Revsbech Jan Sørensen

The formation of atmospheric nitrogen gas by denitrifying bacteria may represent a significant nutrient sink in natural ecosystems. The rate of denitrification has often been difficult to measure in situ, however, and new methodologies should stimulate research on distribution of activity in space and time. The load of fertilizer nitrogen in modem agriculture has led to increasing nutrient reservoirs in recipient subsoils, aquifers, inland waters and coastal seas. By its conversion of nitrate to atmospheric nitrogen, bacterial denitrification is the only biological process to potentially reduce the impact of increasing nutrient loadings by fertilizer nitrogen in the environment. As part of a scientific program set up by the Danish Ministry of Environment to study environment cycling of nitrogen, phosphorous and organic matter (NPO program) in the light of agricultural, domestic and industrial activities, a symposium on DENITRIFICATION IN SOIL AND SEDIMENT was held at the University of Aarhus, Denmark from 6-9 June 19i\9. On the basis of lectures given at the symposium, this book contains a number of invited contributions on the regulation of denitrification activity (control of enzyme synthesis and activity) and measurement of in situ rates of denitrification in terrestrial and aquatic environments (control factors, diel and seasonal variations, etc). Emphasis has been placed on including the recent improvements in methodologies and current understanding of process regulation, however the book also contains examples of integrated research on the significance of denitrification in environmental nutrient cycling.

Denken + Doen = Durven - werkboek kind

by S.M. Bögels

Iedereen is wel eens bang en dat is hartstikke normaal. Maar als de angst ervoor zorgt dat je leven minder leuk en makkelijk is, is het tijd om die angst aan te pakken! Er is echt iets aan te doen! Dit boek helpt jou om met je angsten te leren omgaan. Het begint met uitleg over wat angst is en daarna zijn er veel oefeningen in te vinden. De meeste kinderen die het boek gebruiken, vragen hulp bij een therapeut, die weet hoe dit boek werkt. Als je zo'n therapeut zoekt, kun je het beste even naar je huisarts gaan, die kan je verder helpen.Speciaal voor ouders van kinderen met een angststoornis is er Denken+DoenDurven, werkboek voor ouders. Voor de psychologen, orthopedagogen, psychiaters en andere hulpverleners die met deze kinderen en hun ouders werken is er Behandeling van angststoornissen bij kinderen en adolescenten.

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