November 27, 2020

Download Ebook Free Virus As Populations

Virus as Populations

Virus as Populations
Author : Esteban Domingo
Publisher : Academic Press
Release Date : 2015-09-25
Category : Science
Total pages :428
GET BOOK

Virus as Populations: Composition, Complexity, Dynamics, and Biological Implications explains fundamental concepts that arise from regarding viruses as complex populations when replicating in infected hosts. Fundamental phenomena in virus behavior, such as adaptation to changing environments, capacity to produce disease, probability to be transmitted or response to treatment, depend on virus population numbers and in the variations of such population numbers. Concepts such as quasispecies dynamics, mutations rates, viral fitness, the effect of bottleneck events, population numbers in virus transmission and disease emergence, new antiviral strategies such as lethal mutagenesis, and extensions of population heterogeneity to nonviral systems are included. These main concepts of the book are framed in recent observations on general virus diversity derived from metagenomic studies, and current views on the origin of viruses and the role of viruses in the evolution of the biosphere. Features current views on the key steps in the origin of life and origins of viruses Includes examples relating ancestral features of viruses with their current adaptive capacity Explains complex phenomena in an organized and coherent fashion that is easy to comprehend and enjoyable to read Considers quasispecies as a framework to understand virus adaptability and disease processes

Emerging Viruses in Human Populations

Emerging Viruses in Human Populations
Author : Edward Tabor
Publisher : Elsevier
Release Date : 2006-12-19
Category : Medical
Total pages :374
GET BOOK

Infectious diseases are an ever present threat to humans. In recent years, the threat of these emerging viruses has been greater than ever before in human history, due in large part to global travel by larger numbers of people, and to a lesser extent to disruptions in the interface between developed and undeveloped areas. The emergence of new deadly viruses in human populations during recent decades has confirmed this risk. They remain the third leading cause of deaths in the US and the second world-wide. Emerging Viruses in Human Populations provides a comprehensive review of viruses that are emerging or that threaten to emerge among human populations in the twenty-first century. It discusses the apprehension over emerging viruses that has intensified due to concerns about bioterrorism. * Presents the history of emerging viruses * Includes chapters on SARS, Pandemic Threat of Avian Influenza Viruses, West Nile Virus, Monkeypox Virus, Hantavirus, Nipah Virus and Hendra Virus, Japanese Encephalitis Virus, Dengue and Crimean-Congo Hemorrhagic Fever Viruses * Discusses surveillance for newly emerging diseases

Quasispecies: Concept and Implications for Virology

Quasispecies: Concept and Implications for Virology
Author : Esteban Domingo
Publisher : Springer Science & Business Media
Release Date : 2006-02-19
Category : Medical
Total pages :410
GET BOOK

Continuous genetic variation and selection of virus subpopulations in the course of RNA virus replications are intimately related to viral disease mechanisms. The central topics of this volume are the origins of the quasispecies concept, and the implications of quasispecies dynamics for viral populations.

From Virus Populations to Epidemics

From Virus Populations to Epidemics
Author : Duncam Stewart Callaway
Publisher : Unknown
Release Date : 2001
Category :
Total pages :308
GET BOOK

The study of the population dynamics of disease ranges from the scale of individual cells interacting with virus particles to the structure of the host interaction network. This thesis represents a broad survey of the mathematics of disease across these scales. I have used differential equations to examine the role of competition among viral strains on the progression of HIV infected persons to AIDS, and the factors that lead to the persistence of viral replication in HIV patients undergoing potent drug therapies. At the epidemic level, I have used difference equations to understand the effect of pathogen mutation and host immunity on disease persistence. I have used generating function methods and concepts from graph theory to probe the kinds of host interactions, in particular the distribution of contact rates, which lead to successful vaccination programs. Lastly, I have explored a model of network growth to examine the assumptions made in previous work.

Molecular Basis of Virus Evolution

Molecular Basis of Virus Evolution
Author : Adrian J. Gibbs,Charles H. Calisher,Fernando García-Arenal
Publisher : Cambridge University Press
Release Date : 2005-11-17
Category : Medical
Total pages :624
GET BOOK

This 1995 book covers virus evolution, genetics and interaction with host for virologists and evolutionists.

Diversity of Plant Virus Populations: A Valuable Tool for Epidemiological Studies

Diversity of Plant Virus Populations: A Valuable Tool for Epidemiological Studies
Author : Fernando Escriu
Publisher : Unknown
Release Date : 2017
Category : Medicine
Total pages :129
GET BOOK

Plant viruses, as any other living organisms, differ genetically from each other as a result of processes (such as mutation, recombination and other forms of genetic exchange) that generate genetic variation in each generation during their reproduction and processes (such as selection, migration and genetic drift) that modulate this variation, determine the distribution of the genetic variants within a population (id est, the genetic structure of the population) and how it changes with time, in a dynamical phenomenon called evolution. For plant viruses, evolutionary forces that generate and modulate the genetic diversity of their populations are often associated to different phases in their biology and ecology, such as virus-host interactions and host to host transmission. Forces that shape the evolution of plant viruses are at the same time key factors affecting their pathogenic properties, including their ability to cause diseases (an aspect that is studied in the field of epidemiology). The present chapter aims to illustrate how measurement and analysis of genetic diversity and structure of plant virus populations are essential to the current knowledge on the evolutionary biology of plant viruses and how evolutionary factors have a relevant role in the dynamics of virus populations and therefore, in the epidemiology of plant virus diseases.

Virus Dynamics : Mathematical Principles of Immunology and Virology

Virus Dynamics : Mathematical Principles of Immunology and Virology
Author : Martin Nowak,Robert M. May
Publisher : Oxford University Press, UK
Release Date : 2000-11-23
Category :
Total pages :250
GET BOOK

This groundbreaking book describes the emerging field of theoretical immunology, in particular the use of mathematical models to describe the spread of infectious diseases within patients. It reveals fascinating insights into the dynamics of viral and other infections, and the interactions between infectious agents and immune responses. Structured around the examples of HIV/AIDS and hepatitis B, Nowak and May show how mathematical models can help researchers to understand the detailed dynamics of infection and the effects of antiviral therapy. Models are developed to describe the dynamics of drug resistance, immune responses, viral evolution and mutation, and to optimise the design of therapy and vaccines. - ;We know, down to the tiniest details, the molecular structure of the human immunodeficiency virus (HIV). Yet despite this tremendous accomplishment, and despite other remarkable advances in our understanding of individual viruses and cells of the immune system, we still have no agreed understanding of the ultimate course and variability of the pathogenesis of AIDS. Gaps in our understanding like these impede our efforts towards developing effective therapies and preventive vaccines. Martin Nowak and Robert M May describe the emerging field of theoretical immunology in this accessible and well- written text. Using mathematical modelling techniques, the authors set out their ideas about how populations of viruses and populations of immune system cells may interact in various circumstances, and how infectious diseases spread within patients. They explain how this approach to understanding infectious diseases can reveal insights into the dynamics of viral and other infections, and the interactions between infectious agents and immune responses. The book is structured around the examples of HIV/AIDS and Hepatitis B virus, although the approaches described will be more widely applicable. The authors use mathematical tools to uncover the detailed dynamics of the infection and the effects of antiviral therapy. Models are developed to describe the emergence of drug resistance, and the dynamics of immune responses, viral evolution, and mutation. The practical implications of this work for optimisation of the design of therapy and vaccines are discussed. The book concludes with a glance towards the future of this fascinating, and potentially highly useful, field of study. - ;... an excellent introduction to a field that has the potential to advance substantially our understanding of the complex interplay between virus and host - Nature

Plant Virus Evolution

Plant Virus Evolution
Author : Marilyn J. Roossinck
Publisher : Springer Science & Business Media
Release Date : 2008-02-23
Category : Science
Total pages :224
GET BOOK

This book provides a comprehensive look at the field of plant virus evolution. It is the first book ever published on the topic. Individual chapters, written by experts in the field, cover plant virus ecology, emerging viruses, plant viruses that integrate into the host genome, population biology, evolutionary mechanisms and appropriate methods for analysis. It covers RNA viruses, DNA viruses, pararetroviruses and viroids, and presents a number of thought-provoking ideas.

Citrus Tristeza Virus Populations in Grapefruit Trees, Pre-immunized with Two Different Cross-protecting Sources

Citrus Tristeza Virus Populations in Grapefruit Trees, Pre-immunized with Two Different Cross-protecting Sources
Author : David Read
Publisher : Unknown
Release Date : 2011
Category : Citrus
Total pages :308
GET BOOK

Citrus tristeza virus (CTV) is responsible for the most devastating viral disease of citrus crops and affects the profitability of citriculture on a worldwide scale. In South Africa, where CTV is endemic, the devastating effects of CTV severe-strain infections are reduced through the intentional inoculation of virus-free budwood with a mild-strain cross-protecting source. Cross-protection breakdown however occurs in grapefruit trees in South Africa and results in a reduction of yield and quality in grapefruit producing areas. Grapefruit cultivars are particularly sensitive to the stem-pitting effects of some severe CTV strains and despite the rigorous cross-protection scheme, severe stem-pitting and decline symptoms are still observed in the field. The GFMS 12 cross-protecting isolate was used as the cross-protecting source for grapefruit plantings in South Africa until its use was terminated in 2007. As early as 1993 however, severe stem-pitting was observed in the field. GFMS 35 has been employed as an alternate cross-protecting source, due to the apparent poor cross-protection ability of GFMS 12. Using nucleotide sequence analysis of a 5’ variable region (A-region) and a 3’ conserved region (p23 gene region), CTV population studies were performed on GFMS 12 and GFMS 35 pre-immunised Star Ruby and Flame trees in the field, in the hot production area of Malelane. The viral population of GFMS 12 and GFMS 35 sources, maintained on Mexican Lime and Star Ruby, plants were characterized as references. Severe VT-like strains dominated (up to 100% of clones) in all of the field samples. Of the two grapefruit cultivars sampled, no clear differences in their strain assemblage was obtained, suggesting that relative to each other, these cultivars played no role in shaping the CTV population strain composition that were observed. VT-like strain dominance was also observed in most of the sources maintained on Star Ruby. A shift in population strain composition was observed in the sources maintained on Mexican lime suggesting the important role that hosts may play in strain selection. A number of anomalous results were obtained for the sources that appeared not to follow the “general trend” of population strain composition observed in the other samples. These anomalies may have been caused by when the samples were collected, the age of the tissue material collected, PCR bias during amplification or some other factor resulting in a population shift in the sources. From these results it is near impossible to pinpoint the exact mechanism responsible for CTV cross-protection breakdown. However, the scale of the complexity of CTV population dynamics in South Africa has become clear. From this it will be possible to begin changing the way that cross-protection candidates are evaluated in South Africa, from an entirely empirical approach to one that incorporates much needed molecular methods.

The Nature of RNA Virus Quasispecies Populations

The Nature of RNA Virus Quasispecies Populations
Author : Elizabeth Anne Duarte
Publisher : Unknown
Release Date : 1993
Category :
Total pages :348
GET BOOK

Origin and Evolution of Viruses

Origin and Evolution of Viruses
Author : Esteban Domingo,Colin R. Parrish,John J. Holland
Publisher : Elsevier
Release Date : 2008-06-23
Category : Science
Total pages :560
GET BOOK

New viral diseases are emerging continuously. Viruses adapt to new environments at astounding rates. Genetic variability of viruses jeopardizes vaccine efficacy. For many viruses mutants resistant to antiviral agents or host immune responses arise readily, for example, with HIV and influenza. These variations are all of utmost importance for human and animal health as they have prevented us from controlling these epidemic pathogens. This book focuses on the mechanisms that viruses use to evolve, survive and cause disease in their hosts. Covering human, animal, plant and bacterial viruses, it provides both the basic foundations for the evolutionary dynamics of viruses and specific examples of emerging diseases. * NEW - methods to establish relationships among viruses and the mechanisms that affect virus evolution * UNIQUE - combines theoretical concepts in evolution with detailed analyses of the evolution of important virus groups * SPECIFIC - Bacterial, plant, animal and human viruses are compared regarding their interation with their hosts

The Effect of Within-host Virus Population Growth and Interspecific Competition on Aphid Transmission and Population Structure of Barley Yellow Dwarf Virus

The Effect of Within-host Virus Population Growth and Interspecific Competition on Aphid Transmission and Population Structure of Barley Yellow Dwarf Virus
Author : Gerod Sharper Hall
Publisher : Unknown
Release Date : 2007
Category :
Total pages :182
GET BOOK

Barley yellow dwarf virus (BYDV) (Luteoviridae) species PAV and PAS are ecologically similar in that they share aphid vectors and host species, but in agricultural fields in New York State we found that the prevalence of PAV was three times greater than that of PAS. To determine if differences in within-host population growth rate affect vector transmission efficiency, disease spread and the distribution of virus types in the host community, this study evaluated the biological characteristics of PAV and PAS species isolates in common agricultural hosts and the outcome of competitive interactions between species in mixed infections. In singly infected plants, PAS population size was 20% greater than that of PAV at 8 days post inoculation (DPI), but by 33 DPI the population size of PAV was 10% greater than that of PAS. In doubly infected plants, by 33 DPI the population size of PAV was 40% greater than that of PAS.

Aquaculture Virology

Aquaculture Virology
Author : Frederick S. B. Kibenge,Marcos Godoy
Publisher : Academic Press
Release Date : 2016-07-11
Category : Technology & Engineering
Total pages :568
GET BOOK

To date textbooks on viruses infecting fish, crustaceans and molluscs, the three main aquatic animal farmed groups, have been on the whole “diseases-centric and individual viral diseases selected based on “epizoo-centric approaches with little to no coverage of the basic biology of the viruses, in contrast to textbooks on viruses infecting terrestrial - farmed, pet, and free-range (wild) - animals and humans. Despite considerable advances in animal virology in recent years coupled with an economically important global aquaculture industry, knowledge of viruses of animal aquaculture is still sparse and in some cases outdated although these viruses are closely related to well-known virus families. The last book in fish virology (Fish viruses and fish viral diseases 1988, Wolf, K.) was published in the 1980s. A lot of work has been done on fish viruses and many new aquatic animal viruses continue to be discovered. Aquaculture Virology provides the current state of knowledge of aquatic animal viruses within the current virus classification and taxonomic context thereby allowing the reader to draw on the principles of general virology. This book is a systematic and concise resource useful to anyone involved with or looking to move into aquaculture and fisheries. Clinical veterinarians, aquaculture disease practitioners, biologists, farmers, and all those in industry, government or academia who are interested in aquatic animal virology will find this book extremely useful. Provides unique comprehensive information on animal viruses for aquaculture and fisheries Presents high quality illustrations of viral structure, diagrams of viral disease processes, gross pathology and histopathology lesions, and summary tables to aid in understanding Describes aquatic animal viruses of the three major aquatic animals, fish, crustaceans, and molluscs, within the current virus classification and taxonomic context thereby allowing the reader to draw on the principles of general virology

Viruses

Viruses
Author : Paula Tennant,Gustavo Fermin,Jerome E. Foster
Publisher : Academic Press
Release Date : 2018-03-12
Category : Science
Total pages :392
GET BOOK

Viruses: Molecular Biology, Host Interactions, and Applications to Biotechnology provides an up-to-date introduction to human, animal and plant viruses within the context of recent advances in high-throughput sequencing that have demonstrated that viruses are vastly greater and more diverse than previously recognized. It covers discoveries such as the Mimivirus and its virophage which have stimulated new discussions on the definition of viruses, their place in the current view, and their inherent and derived ‘interactomics’ as defined by the molecules and the processes by which virus gene products interact with themselves and their host’s cellular gene products. Further, the book includes perspectives on basic aspects of virology, including the structure of viruses, the organization of their genomes, and basic strategies in replication and expression, emphasizing the diversity and versatility of viruses, how they cause disease and how their hosts react to such disease, and exploring developments in the field of host-microbe interactions in recent years. The book is likely to appeal, and be useful, to a wide audience that includes students, academics and researchers studying the molecular biology and applications of viruses Provides key insights into recent technological advances, including high-throughput sequencing Presents viruses not only as formidable foes, but also as entities that can be beneficial to their hosts and humankind that are helping to shape the tree of life Features exposition on the diversity and versatility of viruses, how they cause disease, and an exploration of virus-host interactions

Virus Diseases: New Insights for the Healthcare Professional: 2011 Edition

Virus Diseases: New Insights for the Healthcare Professional: 2011 Edition
Author : Anonim
Publisher : ScholarlyEditions
Release Date : 2012-01-09
Category : Medical
Total pages :706
GET BOOK

Virus Diseases: New Insights for the Healthcare Professional: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Virus Diseases. The editors have built Virus Diseases: New Insights for the Healthcare Professional: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Virus Diseases in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Virus Diseases: New Insights for the Healthcare Professional: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.