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Showing 49,701 through 49,725 of 83,149 results

Modelling Approaches to Understand Salinity Variations in a Highly Dynamic Tidal River: The Case of the Shatt al-Arab River (IHE Delft PhD Thesis Series)

by Ali Dinar Abdullah

This book reports the first systematic monitoring and modelling study on water availability, water quality and seawater intrusion of the Shatt al-Arab River (SAR) on the border of Iraq and Iran, where causes and concentration levels of salinity have not yet been fully understood, let alone addressed, leading to conflicting perceptions of its origin (external or internal), the natural conditions and the practices that can explain the current critical conditions. Current scientific knowledge on the SAR salinity problem is deficient, partially due to the complex and dynamic interaction between marine and terrestrial salinity sources, including return flows by water users of the different water sectors in the Euphrates and Tigris rivers upstream of the SAR. The development of a new series of monitoring stations and various modelling approaches helped to better understand the interactions between these different sources. The comprehensive and detailed dataset formed the basis for a validated analytical model that can predict the extent of seawater relative to other salinity sources in an estuary, and for a hydrodynamic model that can predict salinity changes. The adaptability of the models to changing conditions makes them directly applicable by water managers. The procedure can be applied to other comparable systems.

Modelling Atomic Arrangements in Multicomponent Alloys: A Perturbative, First-Principles-Based Approach (Springer Series in Materials Science #346)

by Christopher D. Woodgate

This book provides a comprehensive overview of a computationally efficient approach for modelling the phase behaviour of multicomponent alloys from first principles, describing both short- and long-range atomic ordering tendencies. The study of multicomponent alloy systems, which combine three or more base elements in near-equal ratios, has garnered significant attention in materials science due to the potential for the creation of novel materials with superior properties for a variety of applications. High-entropy alloys, which contain four or more base elements, have emerged as a particularly fascinating subset of these systems, demonstrating extraordinary strength and fracture resistance, among other desirable properties. The book presents a novel modelling approach for studying the phase behaviour of these systems, which is based on a perturbative analysis of the internal energy of the disordered alloy as evaluated within the Korringa–Kohn–Rostoker (KKR) formulation of density functional theory (DFT), using the coherent potential approximation (CPA) to average over chemical disorder. Application of a Landau-type theory to an approximate form of the Gibbs free energy enables direct inference of chemical disorder/order transitions. In addition, the perturbative analysis facilitates extraction of atom-atom effective pair interactions for further atomistic simulations. The connection between the arrangement of atoms in a material and its magnetic properties is also studied. By outlining and applying the proposed modelling techniques to several systems of interest, this book serves as a valuable resource for materials scientists, physicists, and chemists alike, seeking to understand and develop new alloy systems with enhanced materials properties.

Modelling-based Teaching in Science Education

by John K. Gilbert Rosária Justi

Thisbook argues that modelling should be a component of all school curricula thataspire to provide 'authentic science education for all'. The literature onmodelling is reviewed and a 'model of modelling' is proposed. The conditionsfor the successful implementation of the 'model of modelling' in classrooms areexplored and illustrated from practical experience. The roles of argumentation,visualisation, and analogical reasoning, in successful modelling-based teachingare reviewed. The contribution of such teaching to both the learning of keyscientific concepts and an understanding of the nature of science areestablished. Approaches to the design of curricula that facilitate theprogressive grasp of the knowledge and skills entailed in modelling areoutlined. Recognising that the approach will both represent a substantial changefrom the 'content-transmission' approach to science teaching and be inaccordance with current best-practice in science education, the design ofsuitable approaches to teacher education are discussed. Finally, the challengesthat modelling-based education pose to science education researchers, advancedstudents of science education and curriculum design, teacher educators, publicexaminers, and textbook designers, are all outlined.

Modelling Complex Ecological Dynamics

by Donald Deangelis Hauke Reuter Broder Breckling Melanie Trexler Sven Erik Jørgensen Fred Jopp

Model development is of vital importance for understanding and management of ecological processes. Identifying the complex relationships between ecological patterns and processes is a crucial task. Ecological modelling--both qualitatively and quantitatively--plays a vital role in analysing ecological phenomena and for ecological theory. This textbook provides a unique overview of modelling approaches. Representing the state-of-the-art in modern ecology, it shows how to construct and work with various different model types. It introduces the background of each approach and its application in ecology. Differential equations, matrix approaches, individual-based models and many other relevant modelling techniques are explained and demonstrated with their use. The authors provide links to software tools and course materials. With chapters written by leading specialists, "Modelling Complex Ecological Dynamics" is an essential contribution to expand the qualification of students, teachers and scientists alike.

Modelling Congenital Heart Disease: Engineering a Patient-specific Therapy

by Gianfranco Butera Silvia Schievano Giovanni Biglino Doff B. McElhinney

This book combines medicinal and engineering knowledge to present engineering modelling applications (mainly computational, but also experimental) in the context of facilitating a patient-centred approach to treating congenital heart disease (CHD). After introducing the basic concepts of engineering tools, it discusses modelling and the applications of engineering techniques (e.g. computational fluid dynamics, fluid-structure interaction, structural simulations, virtual surgery, advanced image analysis, 3D printing) in specific congenital heart diseases. It also offers a number of clinical case studies describing the applications in real-life clinical practice. The final section focuses on the importance of surgical training, counselling and patient communication. Considering the unique anatomical arrangement pre/post repair in CHD, as well as the different surgical strategy and device options (e.g. stents) for interventions, a patient-specific approach is certainly warranted in this area of medicine, and engineering is helping improve our understanding of individual patients and their particular anatomy and physiology. To reinforce the idea of a necessary dialogue between clinicians and engineers, this book has not only been edited by two cardiologists and two bioengineers, but each chapter has been written by a clinician and an engineer, incorporating both voices in the description of state-of-the-art models for different CHDs.

Modelling Diesel Combustion (Mechanical Engineering Series)

by P. A. Lakshminarayanan Yogesh V. Aghav

This book comprehensively discusses diesel combustion phenomena like ignition delay, fuel-air mixing, rate of heat release, and emissions of smoke, particulate and nitric oxide. It enables quantitative evaluation of these important phenomena and parameters. Most importantly, it attempts to model them with constants that are independent of engine types and hence they could be applied by the engineers and researchers for a general engine. This book emphasizes the importance of the spray at the wall in precisely describing the heat release and emissions for most of the engines on and off-road. It gives models for heat release and emissions. Every model is thoroughly validated by detailed experiments using a broad range of engines. The book describes an elegant quasi-one-dimensional model for heat release in diesel engines with single as well as multiple injections. The book describes how the two aspects, namely, fuel injection rate and the diameter of the combustion bowl in the piston, have enabled meeting advanced emission, noise, and performance standards. The book also discusses the topics of computational fluid dynamics encompassing RANS and LES models of turbulence. Given the contents, this book will be useful for students, researchers and professionals working in the area of vehicle engineering and engine technology. This book will also be a good professional book for practising engineers in the field of combustion engines and automotive engineering.

Modelling Human-Flood Interactions: A Coupled Flood-Agent-Institution Modelling Framework for Long-Term Flood Risk Management (IHE Delft PhD Thesis Series)

by Yared Abayneh Abebe

The negative impacts of floods are attributed to the extent and magnitude of a flood hazard, and the vulnerability and exposure of natural and human elements. In flood risk management (FRM) studies, it is crucial to model the interaction between human and flood subsystems across multiple spatial, temporal and organizational scales. Models should address the heterogeneity that exists within the human subsystem, and incorporate institutions that shape the behaviour of individuals. Hence, the main objectives of the dissertation are to develop a modelling framework and a methodology to build holistic models for FRM, and to assess how coupled human-flood interaction models support FRM policy analysis and decision-making. To achieve the objectives, the study introduces the Coupled fLood-Agent-Institution Modelling framework (CLAIM). CLAIM integrates actors, institutions, the urban environment, hydrologic and hydrodynamic processes and external factors, which affect FRM activities. The framework draws on the complex system perspective and conceptualizes the interaction of floods, humans and their environment as drivers of flood hazard, vulnerability and exposure. The human and flood subsystems are modelled using agent-based models and hydrodynamic models, respectively. The two models are dynamically coupled to understand human-flood interactions and to investigate the effect of institutions on FRM policy analysis.

Modelling Hydrology, Hydraulics and Contaminant Transport Systems in Python

by Soumendra Nath Kuiry Dhrubajyoti Sen

This book covers theoretical aspects of the physical processes, derivation of the governing equations and their solutions. It focusses on hydraulics, hydrology, and contaminant transport, including implementation of computer codes with practical examples. Python-based computer codes for all the solution approaches are provided for better understanding and easy implementation. The mathematical models are demonstrated through applications and the results are analyzed through data tables, plots, and comparison with analytical and experimental data. The concepts are used to solve practical applications like surface and ground water flow, flood routing, crop water requirement and irrigation scheduling. Combines the area of computational hydraulics, hydrology, and water resources engineering with Python Gives deep description of the basic equations and the numerical solutions of both 1D and 2D problems including the numerical codes Includes step-by-step translation of numerical algorithms in computer codes with focus on learners and practitioners Demonstration of theory, mathematical models through practical applications Analysis of each example through data tables, plots, and correlation with reality This book is aimed at senior undergraduates and graduate students in Civil Engineering, Coastal Engineering, Hydrology, and Water Resources Engineering.

Modelling in Nanoporous Shale: Gas-water Occurrence and Transport (Advances in Oil and Gas Exploration & Production)

by Liehui Zhang Tao Zhang Yulong Zhao

This book addresses the problems involved in the modelling and simulation of shale gas reservoirs at pore scale, and details recent advances in the field. It presents the construction of simulation methods, mainly using the lattice Boltzmann method (LBM), that describe sorption, flow, and transport in nanoporous shale with some case studies. This book highlights the nanoscale effects, ascribed to the large surface-to-volume ratio, on fluids occurrence and transport physics. It discusses some interesting phenomena occurs at nanoporous shale, such as absorbed water film, water condensation, sorption hysteresis, surface excess adsorption, Knudsen diffusion, surface diffusion, structural fluid density, no-slip boundary, etc. The key techniques and methods introduced in this book provide the basis for accurate prediction of gas-well productivity. The basic principles and modeling methods are also relevant to many other nanoporous applications in science and engineering. The book aims to provide a valuable reference resource for researchers and professional scientists and engineers working on shale gas development and nanoporous media research.

Modelling Insect Populations in Agricultural Landscapes (Entomology in Focus #8)

by Rafael A. Moral Wesley A. C. Godoy

This book combines chapters emphasising mathematical, statistical, and computational modelling applied to insect populations, particularly pests or natural enemies in agricultural landscapes. There is a gap between agricultural pest experimentation and ecological theory, which requires a connection to supply models with laboratory, and field estimates and projects receiving inputs and insights from models. In addition, decision-making in entomology with respect to pest management and biological conservation of natural enemies has been supported by results obtained from different computational and mathematical approaches. This book brings contemporary issues related to optimization in spatially structured landscapes, insect movement, stability analysis, game theory, machine learning, computer vision, Bayesian modelling, as well as other frameworks.

Modelling Learners and Learning in Science Education

by Keith S. Taber

This book sets out the necessary processes and challenges involved in modeling student thinking, understanding and learning. The chapters look at the centrality of models for knowledge claims in science education and explore the modeling of mental processes, knowledge, cognitive development and conceptual learning. The conclusion outlines significant implications for science teachers and those researching in this field. This highly useful work provides models of scientific thinking from different field and analyses the processes by which we can arrive at claims about the minds of others. The author highlights the logical impossibility of ever knowing for sure what someone else knows, understands or thinks, and makes the case that researchers in science education need to be much more explicit about the extent to which research onto learners' ideas in science is necessarily a process of developing models. Through this book we learn that research reports should acknowledge the role of modeling and avoid making claims that are much less tentative than is justified as this can lead to misleading and sometimes contrary findings in the literature. In everyday life we commonly take it for granted that finding out what another knows or thinks is a relatively trivial or straightforward process. We come to take the 'mental register' (the way we talk about the 'contents' of minds) for granted and so teachers and researchers may readily underestimate the challenges involved in their work.

Modelling Metabolism with Mathematica

by Peter Mulquiney Philip W. Kuchel

With the advent of sophisticated general programming environments like Mathematica, the task of developing new models of metabolism and visualizing their responses has become accessible to students of biochemistry and the life sciences in general. Modelling Metabolism with Mathematica presents the approaches, methods, tools, and algorithms for mode

Modelling Natural Action Selection

by Anil K. Seth Tony J. Prescott Joanna J. Bryson

Action selection is the task of doing the right thing at the right time. It requires the assessment of available alternatives, executing those most appropriate, and resolving conflicts among competing goals and possibilities. Using advanced computational modelling, this book explores cutting-edge research into action selection in nature from a wide range of disciplines, from neuroscience to behavioural ecology, and even political science. It delivers new insights into both detailed and systems-level attributes of natural intelligence and demonstrates advances in methodological practice. Contributions from leading researchers cover issues including whether biological action selection is optimal, neural substrates for action selection in the vertebrate brain, perceptual selection in decision making, and interactions between group and individual action selection. This first integrated review of action selection in nature contains a balance of review and original research material, consolidating current knowledge into a valuable reference for researchers while illustrating potential paths for future studies.

Modelling Nature: An introduction to mathematical modelling of natural systems

by Edward Gillman Michael Gillman

The use of mathematical models is a fundamental aspect of modern science. With computers now allowing previously difficult calculations to be done quickly and easily, an understanding of mathematics and an appreciation for modelling is possible even in fields with traditionally less mathematical content. Modelling Nature introduces basic concepts in mathematical modelling applied to natural systems to tackle real-world problems from fields such as physics, ecology, geology and epidemiology. It shows how using models can help to unravel complex issues such as the melting of the Arctic ice, the spread of infectious disease and the age of the Earth. The text helps students to build steadily upon a basic level of mathematics, to a more advanced understanding of mathematical concepts, for a thorough understanding of a variety of mathematical techniques. Key features include: Worked through calculations, with clear steps that can be followed with just a calculator, pen and paper or popular software packages. Intuitive introduction of advanced mathematical techniques in the context of model building, for an understanding of real-life application. An emphasis on an overall philosophy of building models, drawing repeatedly from the key elements of data, physical processes and mathematical methods to develop and refine models.

Modelling Nature: An introduction to mathematical modelling of natural systems

by Edward Gillman Michael Gillman

This short textbook introduces students to the concept of describing natural systems using mathematical models. We highlight the variety of ways in which natural systems lend themselves to mathematical description and the importance of models in revealing fundamental processes. The process of science via the building, testing and use of models (theories) is described and forms the structure of the book. The book covers a broad range from the molecular to ecosystems and whole-Earth phenomena. Themes running through the chapters include scale (temporal and spatial), change (linear and nonlinear), emergent phenomena and uncertainty. Mathematical descriptions are kept to a minimum and we illustrate mechanisms and results in graphical form wherever possible. Essential mathematical details are described fully, with the use of boxes. The mathematics supports but does not lead the text.

Modelling Nature: An Opinionated Introduction to Scientific Representation (Synthese Library #427)

by Roman Frigg James Nguyen

This monograph offers a critical introduction to current theories of how scientific models represent their target systems. Representation is important because it allows scientists to study a model to discover features of reality. The authors provide a map of the conceptual landscape surrounding the issue of scientific representation, arguing that it consists of multiple intertwined problems. They provide an encyclopaedic overview of existing attempts to answer these questions, and they assess their strengths and weaknesses. The book also presents a comprehensive statement of their alternative proposal, the DEKI account of representation, which they have developed over the last few years. They show how the account works in the case of material as well as non-material models; how it accommodates the use of mathematics in scientific modelling; and how it sheds light on the relation between representation in science and art. The issue of representation has generated a sizeable literature, which has been growing fast in particular over the last decade. This makes it hard for novices to get a handle on the topic because so far there is no book-length introduction that would guide them through the discussion. Likewise, researchers may require a comprehensive review that they can refer to for critical evaluations. This book meets the needs of both groups.

Modelling Non-Markovian Quantum Systems Using Tensor Networks (Springer Theses)

by Aidan Strathearn

This thesis presents a revolutionary technique for modelling the dynamics of a quantum system that is strongly coupled to its immediate environment. This is a challenging but timely problem. In particular it is relevant for modelling decoherence in devices such as quantum information processors, and how quantum information moves between spatially separated parts of a quantum system.The key feature of this work is a novel way to represent the dynamics of general open quantum systems as tensor networks, a result which has connections with the Feynman operator calculus and process tensor approaches to quantum mechanics. The tensor network methodology developed here has proven to be extremely powerful: For many situations it may be the most efficient way of calculating open quantum dynamics. This work is abounds with new ideas and invention, and is likely to have a very significant impact on future generations of physicists.

Modelling Nutrient Digestion and Utilisation in Farm Animals

by N. Friggens D. Sauvant P. Faverdin J. Van Milgen

For more than 30 years, modelling has been an important method for integrating, in a flexible, comprehensive and widely applicable way, basic knowledge and biological concepts on digestion and metabolism in farm animals. The purpose of this book is to present the 'state of art' in this area. The chapters are written by leading teams and researchers in this field of study, mainly from Europe, North America and Australasia. Considerable progress has been made in topics dealing with: modelling methods, feeding behaviour, digestion and metabolic processes in ruminants and monogastric animals. This progress is clearly illustrated by the emergence of a new paradigm in animal nutrition, which has moved from the aim to cover the requirements of the animal to explaining and predicting the responses of the animals to diets (e.g., productivity and efficiency, impact on quality of products, environmental aspects, health and well-being). In this book several chapters illustrate that through empirical models, meta-analysis is an efficient tool to synthesize information gathered over recent decades. In addition, compared with other books on modelling farm animal nutrition, two new aspects received particular attention: expanding knowledge of the individual animal to understanding the functioning and management of herds, and the consideration of the environmental impact of animal production. This book is a valuable source of information for researchers, nutritionists, advisors, and graduate students who want to have up-to-date and concise information on mathematical modelling applied to farm animals.

Modelling of Convective Heat and Mass Transfer in Nanofluids with and without Boiling and Condensation (Mathematical Engineering)

by Andriy A. Avramenko Igor V. Shevchuk

This book presents step-by-step description of the use of Lie group analysis to find symmetry forms and similarity solutions for single- and two-phase laminar and turbulent flows of nanofluids. It outlines novel and unique analytical solutions validated via comparisons with experimental data. The main part of the book is devoted to analytical modeling of film condensation of still and moving vapor with nanoparticles, stable film boiling of nanofluids, instantaneous unsteady boiling and condensation of nano- and ordinary fluids and clarification and quantification of instability conditions in the vapor layer, as well as centrifugal and Dean instability in nanofluids. It was demonstrated that such complex phenomena can be successfully simulated using the proposed approaches validated via reliable experiments. The book is intended for scientists, engineers, graduate and undergraduate students specializing in the area of engineering thermodynamics, heat and mass transfer and energy systems.

Modelling of Convective Heat and Mass Transfer in Rotating Flows

by Igor V. Shevchuk

This monograph presents results of the analytical and numerical modeling of convective heat and mass transfer in different rotating flows caused by (i) system rotation, (ii) swirl flows due to swirl generators, and (iii) surface curvature in turns and bends. Volume forces (i. e. centrifugal and Coriolis forces), which influence the flow pattern, emerge in all of these rotating flows. The main part of this work deals with rotating flows caused by system rotation, which includes several rotating-disk configurations and straight pipes rotating about a parallel axis. Swirl flows are studied in some of the configurations mentioned above. Curvilinear flows are investigated in different geometries of two-pass ribbed and smooth channels with 180° bends. The author demonstrates that the complex phenomena of fluid flow and convective heat transfer in rotating flows can be successfully simulated using not only the universal CFD methodology, but in certain cases by means of the integral methods, self-similar and analytical solutions. The book will be a valuable read for research experts and practitioners in the field of heat and mass transfer.

Modelling of GPCRs

by Andrea Strasser Hans-Joachim Wittmann

G protein coupled receptors (GPCRs) comprise an important protein family, which is involved in signal transduction in the cell. Besides that a large number of drugs, available on market, address GPCRs. For an efficient and improved development of appropriate drugs, molecular modelling of GPCRs is - in order to understand the ligand-receptor interactions and functionality of GPCRs on molecular level - an important tool. The book "Modelling of GPCRs - a practical handbook" is focussed onto a practical introduction into molecular modelling of GPCRs. This book is very useful for beginners in GPCR modelling, but also addresses the advanced GPCR modeller: On the one hand, the book introduces principles of GPCR modelling, including extensive examples. On the other hand, detailed outlooks onto advanced GPCR modelling techniques are presented. Furthermore, the book includes important data, like information about crystal structures in a summarized manner or amino acid sequences, which are essential for GPCR modelling in general. Due to an increase in efficacy and data handling most modellers use LINUX as operating system. To address this, a summary of most important LINUX commands with examples is presented within the book.

Modelling of Plasmonic and Graphene Nanodevices

by Javier Munárriz Arrieta

The thesis covers a broad range of electronic, optical and opto-electronic devices and various predicted physical effects. In particular, it examines the quantum interference transistor effect in graphene nanorings; tunable spin-filtering and spin-dependent negative differential resistance in composite heterostructures based on graphene and ferromagnetic materials; optical and novel electro-optical bistability and hysteresis in compound systems and the real-time control of radiation patterns of optical nanoantennas. The direction of the main radiation lobe of a regular plasmonic array can be changed abruptly by small variations in external control parameters. This optical effect, apart from its relevance for applications, is a revealing example of the Umklapp process and, thus, is a visual manifestation of one of the most fundamental laws of solid state physics: the conservation of the quasi-momentum to within a reciprocal lattice vector. The thesis analyzes not only results for particular device designs but also a variety of advanced numerical methods which are extended by the author and described in detail. These methods can be used as a sound starting point for further research.

The Modelling of Radiation Damage in Metals Using Ehrenfest Dynamics

by Christopher Race

Atomistic simulations of metals under irradiation are indispensable for understanding damage processes at time- and length-scales beyond the reach of experiment. Previously, such simulations have largely ignored the effect of electronic excitations on the atomic dynamics, even though energy exchange between atoms and electrons can have significant effects on the extent and nature of radiation damage. This thesis presents the results of time-dependent tight-binding simulations of radiation damage, in which the evolution of a coupled system of energetic classical ions and quantum mechanical electrons is correctly described. The effects of electronic excitations in collision cascades and ion channeling are explored and a new model is presented, which makes possible the accurate reproduction of non-adiabatic electronic forces in large-scale classical molecular dynamics simulations of metals.

Modelling of Soil Behaviour with Hypoplasticity: Another Approach to Soil Constitutive Modelling (Springer Series in Geomechanics and Geoengineering)

by David Mašín

<p>This book explains the hypoplastic modelling framework. It is divided into two parts, the first of which is devoted to principles of hypoplasticity. First, the basic features of soil’s mechanical behaviour are introduced, namely non-linearity and asymptotic properties. These features are then incorporated into simple one-dimensional hypoplastic equations for compression and shear. Subsequently, a hypoplastic equivalent of the Modified Cam-Clay model is developed in 2D space using stress and strain invariants to demonstrate key similarities and differences between elasto-plastic and hypoplastic formulations. Lastly, the mathematical structure of hypoplastic models is explained by tracing their historical development, from the early trial-and-error models to more recent approaches. In turn, Part II introduces specific hypoplastic models for soils. First, two reference models for sand and clay are defined. After summarising their mathematical formulations, calibration procedures are described and discussed. Subsequently, more advanced modelling approaches are covered: the intergranular strain concept incorporating the effects of small strain stiffness and cyclic loading, viscohypoplasticity for predicting rate effects, soil structure to represent structured and bonded materials and soil anisotropy. The book concludes with a description of partial saturation and thermal effects: topics that are increasingly important to the disciplines of energy and environmental geotechnics. <p>Selecting a constitutive model and its parameters is often the most important and yet challenging part of any numerical analysis in geotechnical engineering. Hypoplasticity involves a specific class of soil constitutive models, which are described in detail here. The book offers an essential resource, both for model users who need a more advanced model for their geotechnical calculations and are mainly interested in parameter calibration procedures, and for model developers who are seeking a comprehensive understanding of the mathematical structure of hypoplasticity.</p>

Modelling of the Microfiltration Process

by Zhan Wang

This book presents the editor's recently proposed mathematical models for flux prediction in membrane filtration. It also provides typical mathematical models used in the development of membrane fouling control and explains the step-by-step derivation of these models. The book then highlights how these mathematical models provide insights into the mechanisms of membrane fouling and cleaning to allow for a better understanding of the complete membrane filtration process. Given its scope, this book appeals to a broad readership, particularly professionals at universities as well as engineers engaged in membrane separation in an industrial process.

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Showing 49,701 through 49,725 of 83,149 results