Vores kunder ligger øverst på Google

Google Ads Specialister fra Vestjylland

Vi er 100% dedikerede til Google Annoncering – Vi har mange års erfaring med Google Ads og den bruger vi på at opsætte, optimere & vedligeholde vores fantastiske kunders konti.

100% Specialiseret i Google Ads
Vi har mange års erfaring fra +300 konti
Ingen lange bindinger & evighedskontrakter
Jævnlig opfølgning med hver enkelt kunde
Vi tager din virksomhed seriøst
KONTAKT OS
LÆS UDTALELSER & SUCCESHISTORIER

42 resultater (0,27529 sekunder)

Vis alle filtre

Mærke

Butik

Pris (EUR)

Nulstil filter

Produkter
Fra
Butikker

Introduction to Protein Structure - Carl Ivar Branden - Bog - Taylor & Francis Inc - Plusbog.dk

Introduction to Protein Structure - Carl Ivar Branden - Bog - Taylor & Francis Inc - Plusbog.dk

Introduction to Protein Structure provides an account of the principles of protein structure, with examples of key proteins in their biological context generously illustrated in full-color to illuminate the structural principles described in the text. The first few chapters introduce the general principles of protein structure both for novices and for non-specialists needing a primer. Subsequent chapters use specific examples of proteins to show how they fulfill a wide variety of biological functions. The book ends with chapters on the experimental approach to determining and predicting protein structure, as well as engineering new proteins to modify their functions.

DKK 806.00
1

Protein Purification - Philip (nottingham Trent University Bonner - Bog - Taylor & Francis Inc - Plusbog.dk

Protein Purification - Philip (nottingham Trent University Bonner - Bog - Taylor & Francis Inc - Plusbog.dk

This second edition of Protein Purification provides a guide to the major chromatographic techniques, including non-affinity absorption techniques, affinity procedures, non-absorption techniques and methods for monitoring protein purity. The new edition of the book has been organized to encourage incremental learning about the topic, starting with the properties of water, progressing through the characteristics of amino acids and proteins which relate to the purification process. There is an overview of protein strategy and equipment, followed by discussions and examples of each technique and their applications. The basic theory and simple explanations given in Protein Purification make it an ideal handbook for final year undergraduates, and postgraduates, who are conducting research projects. It will also be a useful guide to more experienced researchers who need a good overview of the techniques and products used in protein purification. Key Features * Guide to the major techniques used in protein purification * Includes flowcharts to help the reader slect the best purification strategy * Contains step-by-step protocols that guide the reader through each technique and its use * Includes exercises and solutions

DKK 717.00
1

Protein Actions - Ivet Bahar - Bog - Taylor & Francis Inc - Plusbog.dk

Protein Actions - Ivet Bahar - Bog - Taylor & Francis Inc - Plusbog.dk

Protein Actions: Principles and Modeling is aimed at graduates, advanced undergraduates, and any professional who seeks an introduction to the biological, chemical, and physical properties of proteins. Broadly accessible to biophysicists and biochemists, it will be particularly useful to student and professional structural biologists and molecular biophysicists, bioinformaticians and computational biologists, biological chemists (particularly drug designers) and molecular bioengineers. The book begins by introducing the basic principles of protein structure and function. Some readers will be familiar with aspects of this, but the authors build up a more quantitative approach than their competitors. Emphasizing concepts and theory rather than experimental techniques, the book shows how proteins can be analyzed using the disciplines of elementary statistical mechanics, energetics, and kinetics. These chapters illuminate how proteins attain biologically active states and the properties of those states. The book ends with a synopsis the roles of computational biology and bioinformatics in protein science.

DKK 993.00
1

How Proteins Work - Mike Williamson - Bog - Taylor & Francis Inc - Plusbog.dk

How Proteins Work - Mike Williamson - Bog - Taylor & Francis Inc - Plusbog.dk

How Proteins Work is an up-to-date and authoritative account of protein function in living systems, explained within the governing parameters of physics, chemistry, and evolution. This text will enable advanced undergraduate students in biochemistry and biophysics to understand the relationships among protein function, structure, and dynamics. It will also serve as a valuable resource for graduate students and researchers looking for a reference on the fundamentals underlying protein function. By providing an integrated view of proteins at both a cellular and systemic level, this textbook shows how evolution drives proteins to adopt domain structures that combine to achieve biological outcomes. The association of proteins into dimers, molecular machines, and multi-enzymatic complexes enables them to achieve catalytic and functional efficiency.

DKK 806.00
1

Proteins - Paulo Almeida - Bog - Taylor & Francis Inc - Plusbog.dk

Proteins - Paulo Almeida - Bog - Taylor & Francis Inc - Plusbog.dk

Proteins: Concepts in Biochemistry teaches the biochemical concepts underlying protein structure, evolution, stability, folding, and enzyme kinetics, and explains how interactions in macromolecular structures determine protein function. Intended for a one-semester course in biochemistry or biophysical chemistry with a focus on proteins, this textbook emphasizes the logic underlying biophysical chemical principles. Problems throughout the book encourage statistical and quantitative thinking. The text is ideal for senior undergraduates, first year graduate students, and practitioners in chemistry, biochemistry, biology, and biophysics.

DKK 693.00
1

Introduction to Proteins - Nir (tel Aviv University Ben Tal - Bog - Taylor & Francis Inc - Plusbog.dk

Introduction to Proteins - Nir (tel Aviv University Ben Tal - Bog - Taylor & Francis Inc - Plusbog.dk

Introduction to Proteins provides a comprehensive and state-of-the-art introduction to the structure, function, and motion of proteins for students, faculty, and researchers at all levels. The book covers proteins and enzymes across a wide range of contexts and applications, including medical disorders, drugs, toxins, chemical warfare, and animal behavior. Each chapter includes a Summary, Exercises, and References. New features in the thoroughly-updated second edition include: - A brand-new chapter on enzymatic catalysis , describing enzyme biochemistry, classification, kinetics, thermodynamics, mechanisms, and applications in medicine and other industries. These are accompanied by multiple animations of biochemical reactions and mechanisms, accessible via embedded QR codes (which can be viewed by smartphones) - An in-depth discussion of G-protein-coupled receptors (GPCRs) - A wider-scale description of biochemical and biophysical methods for studying proteins , including fully accessible internet-based resources , such as databases and algorithms - Animations of protein dynamics and conformational changes , accessible via embedded QR codes Additional features - Extensive discussion of the energetics of protein folding, stability and interactions - A comprehensive view of membrane proteins, with emphasis on structure-function relationship - Coverage of intrinsically unstructured proteins, providing a complete, realistic view of the proteome and its underlying functions - Exploration of industrial applications of protein engineering and rational drug design - Each chapter includes a Summary, Exercies, and References - Approximately 300 color images - Downloadable solutions manual available at www.crcpress.com For more information, including all presentations, tables, animations, and exercises, as well as a complete teaching course on proteins'' structure and function, please visit the author''s website. Praise for the first edition "This book captures, in a very accessible way, a growing body of literature on the structure, function and motion of proteins. This is a superb publication that would be very useful to undergraduates, graduate students, postdoctoral researchers, and instructors involved in structural biology or biophysics courses or in research on protein structure-function relationships." -- David Sheehan , ChemBioChem , 2011 " Introduction to Proteins is an excellent, state-of-the-art choice for students, faculty, or researchers needing a monograph on protein structure. This is an immensely informative, thoroughly researched, up-to-date text, with broad coverage and remarkable depth. Introduction to Proteins would provide an excellent basis for an upper-level or graduate course on protein structure, and a valuable addition to the libraries of professionals interested in this centrally important field." -- Eric Martz , Biochemistry and Molecular Biology Education , 2012

DKK 884.00
1

Cellular Signal Processing - Karin Muller Decker - Bog - Taylor & Francis Inc - Plusbog.dk

Cellular Signal Processing - Karin Muller Decker - Bog - Taylor & Francis Inc - Plusbog.dk

Cellular Signal Processing offers a unifying view of cell signaling based on the concept that protein interactions act as sophisticated data processing networks that govern intracellular and extracellular communication. It is intended for use in signal transduction courses for undergraduate and graduate students working in biology, biochemistry, bioinformatics, and pharmacology, as well as medical students. The text is organized by three key topics central to signal transduction: the protein network, its energy supply, and its evolution. It covers all important aspects of cell signaling, ranging from prokaryotic signal transduction to neuronal signaling, and also highlights the clinical aspects of cell signaling in health and disease. This new edition includes expanded coverage of prokaryotes, as well as content on new developments in systems biology, epigenetics, redox signaling, and small, non-coding RNA signaling.

DKK 731.00
1

Practical Bioinformatics - Michael Agostino - Bog - Taylor & Francis Inc - Plusbog.dk

Practical Bioinformatics - Michael Agostino - Bog - Taylor & Francis Inc - Plusbog.dk

Practical Bioinformatics is specifically designed for biology majors, with a heavy emphasis on the steps required to perform bioinformatics analysis to answer biological questions. It is written for courses that have a practical, hands-on element and contains many exercises (for example, database searches, protein analysis, data interpretation) to complement the straightforward and practical topics. The chapters are focused on DNA, RNA, and protein sequence analysis—frequently performed subsets of the field of bioinformatics—taking the reader through the commonly asked question “what can I learn about this sequence?” A special note to established scientists: new genomic sequences are being published at an accelerating pace. Although new technology has led to unprecedented accuracy of the sequence, incomplete and challenging assemblies along with imperfect predictive methods are still generating gene models that require verification. With the sequence analysis skills learned from this book, features such as missing exons and incorrect termini can be easily recognized and more accurate gene models can be constructed.

DKK 569.00
1

CRC Handbook of Chemistry and Physics, Student Edition - - Bog - Taylor & Francis Inc - Plusbog.dk

CRC Handbook of Chemistry and Physics, Student Edition - - Bog - Taylor & Francis Inc - Plusbog.dk

This handbook is a ready-reference reliable book of chemical and physical data. It is the 98th Edition and includes a number of new tables to include a new summary table of key properties of the Elements, the table of Isotopes, Gas Clathrates, Ionic Liquids, Protein-Ligand Binding Thermodynamics, Common Drugs, H Chemical Shifts of Contaminants, Electron Affinities, Atonic and Molecular Polarizabilities, IUPAC Guide to Nomenclature of Inorganic Chemistry.

DKK 958.00
1

Family and The Great Outdoors - Ph.d. Turner - Bog - Taylor & Francis Inc - Plusbog.dk

Family and The Great Outdoors - Ph.d. Turner - Bog - Taylor & Francis Inc - Plusbog.dk

This book will capture the heart of everyone who ever climbed a tree or gone fishing with their dad. Beyond that, it takes the reader deep into the life of a man whose father showed him how to hunt as well as how to live and how to pass the heritage on to his sons and theirs. Enjoy personal moments in the life of a great outdoorsman who has keen insight into life, the earth and her creatures. You won''t shake off these stories after closing the book—you''ll be hooked.

DKK 325.00
1

Introduction to Bioinformatics - Anna Tramontano - Bog - Taylor & Francis Inc - Plusbog.dk

Introduction to Bioinformatics - Anna Tramontano - Bog - Taylor & Francis Inc - Plusbog.dk

Guiding readers from the elucidation and analysis of a genomic sequence to the prediction of a protein structure and the identification of the molecular function, Introduction to Bioinformatics describes the rationale and limitations of the bioinformatics methods and tools that can help solve biological problems. Requiring only a limited mathematical and statistical background, the book shows how to efficiently apply these approaches to biological data and evaluate the resulting information. The author, an expert bioinformatics researcher, first addresses the ways of storing and retrieving the enormous amount of biological data produced every day and the methods of decrypting the information encoded by a genome. She then covers the tools that can detect and exploit the evolutionary and functional relationships among biological elements. Subsequent chapters illustrate how to predict the three-dimensional structure of a protein. The book concludes with a discussion of the future of bioinformatics. Even though the future will undoubtedly offer new tools for tackling problems, most of the fundamental aspects of bioinformatics will not change. This resource provides the essential information to understand bioinformatics methods, ultimately facilitating in the solution of biological problems.

DKK 782.00
1

Principles of Systems Biology - Ashok Prasad - Bog - Taylor & Francis Inc - Plusbog.dk

Principles of Systems Biology - Ashok Prasad - Bog - Taylor & Francis Inc - Plusbog.dk

This book provides a broad, integrative overview of systems biology, giving particular attention to functional modeling, analysis, and experimental testing of protein circuits. It begins at the fundamental building blocks of a cell, introducing the underpinnings from thermodynamics and statistical mechanics, and then addresses biochemical networks. The author focuses on giving students the practical toolkit necessary for work in this field, from model estimation to predictive modeling and beyond. Among the key topics discussed in depth are gene transcription, signal transduction, metabolism, synthetic biology, and systems physiology.

DKK 819.00
1

Statistical Modeling and Machine Learning for Molecular Biology - Alan (university Of Toronto Moses - Bog - Taylor & Francis Inc - Plusbog.dk

Statistical Modeling and Machine Learning for Molecular Biology - Alan (university Of Toronto Moses - Bog - Taylor & Francis Inc - Plusbog.dk

Molecular biologists are performing increasingly large and complicated experiments, but often have little background in data analysis. The book is devoted to teaching the statistical and computational techniques molecular biologists need to analyze their data. It explains the big-picture concepts in data analysis using a wide variety of real-world molecular biological examples such as eQTLs, ortholog identification, motif finding, inference of population structure, protein fold prediction and many more. The book takes a pragmatic approach, focusing on techniques that are based on elegant mathematics yet are the simplest to explain to scientists with little background in computers and statistics.

DKK 618.00
1

Multiscale Methods in Molecular Biophysics - - Bog - Taylor & Francis Inc - Plusbog.dk

Multiscale Methods in Molecular Biophysics - - Bog - Taylor & Francis Inc - Plusbog.dk

Multiscale methods are ideally suited to simulate the processes at work in many biomolecular systems, which often span a large range of time and length scales. Multiscale Methods in Molecular Biophysics highlights the advantages of these methods for integrating different levels of detail in a single simulation setting. It covers the practical methodology and successful applications in areas such as enzyme catalysis, protein folding, and ligand binding. The book is divided into three main sections: combination quantum and classical (atomistic) descriptions, approaches that combine atomistic and coarse-grained level of details, and multiscale methods where the resolution coupling is between global collective coordinates and local details.

DKK 1107.00
1

Principles of Evolution - Jonathan (university Of Oxford Bard - Bog - Taylor & Francis Inc - Plusbog.dk

Principles of Evolution - Jonathan (university Of Oxford Bard - Bog - Taylor & Francis Inc - Plusbog.dk

Principles of Evolution covers all aspects of the subject. Following an introductory section that provides necessary background, it has chapters on the evidence for evolution that cover the fossil record, DNA-sequence homologies, and protein homologies (evo-devo). It also includes a full history of life from the first universal common ancestor, through the rise of the eukaryote and on to the major groups of phyla. This section is followed by one on the mechanism of evolution with chapters on variation, selection and speciation. The main part of the book ends with a chapter on human evolution and this is followed by appendices that expand on the making of fossils, the history of the subject and creationism. What marks this book as different from others on evolution is its systems-biology perspective. This new area focuses on the role of protein networks and on multi-level complexity, and is used in three contexts. First, most biological activity is driven by such networks and this has direct implications for understanding evo-devo and for seeing how variation is initiated, mainly during embryogenesis. Second, it provides the natural language for discussing phylogenetics. Third, evolutionary change involves events at levels ranging from the genome to the ecosystem and systems biology provides a context for integrating material of this complexity. The book assumes a basic grounding in biology but little mathematics as the difficult subject of evolutionary population genetics is mainly covered qualitatively, with major results being discussed and used rather than derived. Principles of Evolution will be an interesting and thought-provoking text for undergraduates and graduates across the biological sciences.

DKK 884.00
1

Cooking Innovations - Amos (the Hebrew University Of Jerusalem Nussinovitch - Bog - Taylor & Francis Inc - Plusbog.dk

Cooking Innovations - Amos (the Hebrew University Of Jerusalem Nussinovitch - Bog - Taylor & Francis Inc - Plusbog.dk

While hydrocolloids have been used for centuries, it took molecular gastronomy to bring them to the forefront of modern cuisine. They are among the most commonly used ingredients in the food industry, functioning as thickeners, gelling agents, texturizers, stabilizers, and emulsifiers. They also have applications in the areas of edible coatings and flavor release. Although there are many books describing hydrocolloids and their industrial uses, Cooking Innovations: Using Hydrocolloids for Thickening, Gelling, and Emulsification is the first scientific book devoted to the unique applications of hydrocolloids in the kitchen, covering both past uses and future innovations. Each chapter addresses a particular hydrocolloid, protein hydrocolloid, or protein–polysaccharide complex. Starting with a brief description of the chemical and physical nature of the hydrocolloid, its manufacture, and its biological/toxicological properties, the emphasis is on practical information for both the professional chef and amateur cook. Each chapter includes recipes demonstrating the particular hydrocolloid’s unique abilities in cooking. Several formulations were chosen specifically for food technologists, who will be able to manipulate them for large-scale use or as a starting point for novel industrial formulations. The book covers the most commonly used hydrocolloids, namely, agar–agar, alginates, carrageenan and furcellaran, cellulose derivatives, curdlan, egg proteins, galactomannans, gelatin, gellan gum, gum arabic, konjac mannan, pectin, starch, and xanthan gum. It also discusses combining multiple hydrocolloids to obtain novel characteristics. This volume serves to inspire cooking students and introduce food technologists to the many uses of hydrocolloids. It is written so that chefs, food engineers, food science students, and other professionals will be able to cull ideas from the recipes and gain an understanding of the capabilities of each hydrocolloid.

DKK 1022.00
1

Practical Graph Mining with R - - Bog - Taylor & Francis Inc - Plusbog.dk

Practical Graph Mining with R - - Bog - Taylor & Francis Inc - Plusbog.dk

Discover Novel and Insightful Knowledge from Data Represented as a Graph Practical Graph Mining with R presents a "do-it-yourself" approach to extracting interesting patterns from graph data. It covers many basic and advanced techniques for the identification of anomalous or frequently recurring patterns in a graph, the discovery of groups or clusters of nodes that share common patterns of attributes and relationships, the extraction of patterns that distinguish one category of graphs from another, and the use of those patterns to predict the category of new graphs. Hands-On Application of Graph Data Mining Each chapter in the book focuses on a graph mining task, such as link analysis, cluster analysis, and classification. Through applications using real data sets, the book demonstrates how computational techniques can help solve real-world problems. The applications covered include network intrusion detection, tumor cell diagnostics, face recognition, predictive toxicology, mining metabolic and protein-protein interaction networks, and community detection in social networks. Develops Intuition through Easy-to-Follow Examples and Rigorous Mathematical Foundations Every algorithm and example is accompanied with R code. This allows readers to see how the algorithmic techniques correspond to the process of graph data analysis and to use the graph mining techniques in practice. The text also gives a rigorous, formal explanation of the underlying mathematics of each technique. Makes Graph Mining Accessible to Various Levels of Expertise Assuming no prior knowledge of mathematics or data mining, this self-contained book is accessible to students, researchers, and practitioners of graph data mining. It is suitable as a primary textbook for graph mining or as a supplement to a standard data mining course. It can also be used as a reference for researchers in computer, information, and computational science as well as a handy guide for data analytics practitioners.

DKK 873.00
1

Introduction to Experimental Biophysics (Set) - Jay L. Nadeau - Bog - Taylor & Francis Inc - Plusbog.dk

Introduction to Experimental Biophysics (Set) - Jay L. Nadeau - Bog - Taylor & Francis Inc - Plusbog.dk

This set presents wet lab methods for courses in biophysics or molecular biology. It provides a thorough description of modern experimental and analytical techniques used in biological and biophysical research. The author gives practical, step-by-step guidance on instrumentation and experimental design and includes recipes for common solutions and media, lists of important reagents, and a glossary of biological terms. The manual offers a flexible course plan that permits completion of the labs in either a full term or intensive summer course. Tested in a pedagogical setting, the experiments follow a logical progression beginning with a DNA construct. The book starts with the basics of molecular cloning: amplifying and purifying plasmid, plasmid mapping, and using restriction enzymes. Later experiments deal with more advanced, emerging techniques, such as the synthesis and characterization of quantum dots and gold nanoparticles, protein crystallization, and spectroscopic techniques.

DKK 1143.00
1

Kill the Company - Lisa Bodell - Bog - Taylor & Francis Inc - Plusbog.dk

Kill the Company - Lisa Bodell - Bog - Taylor & Francis Inc - Plusbog.dk

In the ever-changing world of business, we''ve arrived at a point where process has trumped culture, where the race toward efficiency has left us unable to reach our potential. Stuck in the land of status quo, we''ve forgotten how to think. The very structures put in place to help businesses grow are now holding us back;; it''s time to Kill the Company. This book is a call to arms: to start a revolution in how we think and work. But instead of more one-size-fits-all change initiatives forced upon employees, we need to embrace small changes that create ripple effects throughout the organization. Lisa Bodell urges companies to move from "Zombies, Inc." to "Think, Inc." Thinking can no longer be exclusive to the creative team or lead strategists. A culture of curiosity must be fostered among the ranks to shake up our standard practices, from unproductive meetings to go-nowhere strategic planning. This revolution can and will awaken our ability to think, and ultimately, to innovate and grow.

DKK 348.00
1

Introduction to Experimental Biophysics - A Laboratory Guide - Jay L. Nadeau - Bog - Taylor & Francis Inc - Plusbog.dk

Introduction to Experimental Biophysics - A Laboratory Guide - Jay L. Nadeau - Bog - Taylor & Francis Inc - Plusbog.dk

Easily Get Started with Biological Experiments Introduction to Experimental Biophysics - A Laboratory Guide presents wet lab methods for courses in biophysics or molecular biology. A companion to the author’s highly praised An Introduction to Experimental Biophysics: Biological Methods for Physical Scientists , this manual offers a flexible course plan that permits completion of the labs in either a full term or intensive summer course. Tested in a pedagogical setting, the experiments follow a logical progression beginning with a DNA construct. The book starts with the basics of molecular cloning: amplifying and purifying plasmid, plasmid mapping, and using restriction enzymes. Later experiments deal with more advanced, emerging techniques, such as the synthesis and characterization of quantum dots and gold nanoparticles, protein crystallization, and spectroscopic techniques. This accessible guide will help both students and instructors in molecular biology, biophysics, and biomedical engineering. Students will understand how to use a variety of techniques in biological experiments while instructors will get practical guidance on preparing the experiments.

DKK 993.00
1

Abnormal Hemoglobins in Human Populations - Frank. B. Livingstone - Bog - Taylor & Francis Inc - Plusbog.dk

Abnormal Hemoglobins in Human Populations - Frank. B. Livingstone - Bog - Taylor & Francis Inc - Plusbog.dk

Research on abnormal human hemoglobins (protein in blood that carries oxygen), has taught us about the inheritance, biochemistry, and distribution of these traits. This knowledge, coupled with mathematical research using computer models of population genetics, has enabled researchers to marry biological fact and genetic theory. This volume places medical understanding in an evolutionary framework. Using published data on the frequencies of abnormal hemoglobins in the world''s populations, Livingston analyzes and interprets these frequencies in the light of world distribution of different forms of diseases such as malaria. He further develops the genetic theory of the evolutionary homeostasis. Livingston discusses the relation of abnormal hemoglobins to endemic malaria and, shows how natural selection pressures explain the known distribution of these traits. Where non-coinciding distributions arise, the book presents other genetic, anthropological, evolutionary, and epidemiological evidence to explain these discrepancies. This classic work remains a useful sourcebook for professors and graduate students of anthropology, genetics, epidemiology, and hematology.

DKK 542.00
1

Principles of Experimental Design for the Life Sciences - Murray R. Selwyn - Bog - Taylor & Francis Inc - Plusbog.dk

Principles of Experimental Design for the Life Sciences - Murray R. Selwyn - Bog - Taylor & Francis Inc - Plusbog.dk

Let this down-to-earth book be your guide to the statistical integrity of your work. Without relying on the detailed and complex mathematical explanations found in many other statistical texts, Principles of Experimental Design for the Life Sciences teaches how to design, conduct, and interpret top-notch life science studies. Learn about the planning of biomedical studies, the principles of statistical design, sample size estimation, common designs in biological experiments, sequential clinical trials, high dimensional designs and process optimization, and the correspondence between objectives, design, and analysis. Each of these important topics is presented in an understandable and non-technical manner, free of statistical jargon and formulas. Written by a biostatistical consultant with 25 years of experience, Principles of Experimental Design for the Life Sciences is filled with real-life examples from the author''s work that you can quickly and easily apply to your own. These examples illustrate the main concepts of experimental design and cover a broad range of application areas in both clinical and nonclinical research. With this one innovative, helpful book you can improve your understanding of statistics, enhance your confidence in your results, and, at long last, shake off those statistical shackles!

DKK 259.00
1