How does the motor cortex enable mammals to generate accurate, complex, and purposeful movements? A cubic millimeter of motor cortex contains roughly ̃10̂5 cells, an amazing ̃4 Km of axons and ̃0.4 Km of dendrites, somehow wired together with ̃10̂9 synapses. Corticospinal neurons (a.k.a. Betz cells, upper motor neurons) are a key cell type, monosynaptically conveying the output of the cortical circuit to the spinal cord circuits and lower motor neurons. But corticospinal neurons are greatly outnumbered by all the other kinds of neurons in motor cortex, which presumably also contribute crucially to the computational operations carried out for planning, executing, and guiding actions. Determining the wiring patterns, the dynamics of signaling, and how these relate to movement at the level of specific excitatory and inhibitory cell types is critically important for a mechanistic understanding of the input-output organization of motor cortex. While there is a predictive microcircuit hypothesis that relates motor learning to the operation of the cerebellar cortex, we lack such a microcircuit understanding in motor cortex and we consider microcircuits as a central research topic in the field. This Research Topic covers any issues relating to the microcircuit-level analysis of motor cortex. Contributions are welcomed from neuroscientists at all levels of investigation, from in vivo physiology and imaging in humans and monkeys, to rodent models, in vitro anatomy, electrophysiology, electroanatomy, cellular imaging, molecular biology, disease models, computational modeling, and more.
The purpose of this book is to bring together current scientific understanding of wetting behaviour that has been gained from theoretical models and quantitative experimental observations. The materials considered are liquid metals or inorganic glasses in contact with solid metals or ceramics at temperatures of 200-2000oC. Wetting has been a significant scientific concern for the last two centuries and reference will be made to classical work by nineteenth century scientists such as Dupré, Laplace and Young that was validated by observations of the behaviour of chemically inert ambient temperature systems.In attempting to achieve the aims of the book, the text has been divided into ten Chapters that can be grouped into four stages of presentation. The first stage comprises two Chapters that review established and newly developed models for their relevance to wetting behaviour at high temperatures, including recent models that encompass the role of chemical reactions at the solid/liquid interfaces. Attention is paid both to equilibrium wetting behaviour (Chapter 1) and to the factors that control the approach to equilibrium (Chapter 2). Then follow Chapters concerned with experimental techniques for scientific measurement of the extent of wetting (Chapter 3) and with the surface energy data for both metals and non-metals that are essential for quantitative interpretation of wetting behaviour (Chapter 4). Descriptions of experimentally determined and quantified wetting behaviour are presented and interpreted in the third part comprising five Chapters dealing with the characteristics of metal/metal, metal/oxide, metal/non-oxide, metal/carbon and molten glass/solid systems. The book concludes with a Chapter commenting on the role of wetting behaviour in joining similar and dissimilar materials by liquid route techniques.
Joining Processes is aimed at scientists and engineers who need to specify effective means of joining metals and ceramics, and also for undergraduates whose studies encompass joining processes. Joining Processes provides a brief review of the spectrum of joining processes ranging from fusion welding to adhesive bonding, followed by a detailed introduction to brazing, diffusion bonding and their hybrid processes. This book also describes the scientific principles of the joining processes and provides practical information about the optimum selection of joining materials, joint designs and processing parameters. The effects of both similarities and significant differences of the processes on joint properties are emphasised and illustrated by descriptions of case histories of successful applications.
The problem that virtually all cells have in discriminating between "self" and "non-self" molecules and cells has been considered at great length in immuno biology. However, cells that clearly are incapable of carrying out mammalian type immune functions can exhibit exquisite specificity in their capacity to discriminate among syngeneic, allogeneic, and xenogeneic cells. In this volume of Contemporary Topics in Immunobiology we have chosen to consider the general problem of self/non-self discrimination as it is manifest in recognition reactions of plants and invertebrates and in the evolutionary development of the immune response of vertebrates. A broad, many-faceted approach is taken toward fundamental issues in immunobiology in order to develop innovative concepts of receptor function as well as to delineate traditional views. The capacity of plants to discriminate between self and non-self is addressed in Chapter 1 by R. B. Knox and Adrienne E. Clarke. These authors provide examples of cell-cell recognition in plants that parallel those occurring in in vertebrates and vertebrates. In general, tolerance (acceptance) of grafts is re stricted to plants within closely related genera. Recognition is mediated by callus cells, which proliferate at wound surfaces in higher plants, and there is a correlation between cell and tissue type and antigenic markers detectable with the use of mammalian antibodies. Certain flowering plants exhibit precise discrimination in fertilization, when pollen must be from the same species, but fertilization occurs only if the pollen is genetically non-self.
This is a book both for the reader with a casual interest in ancestry, and the serious researcher of Scottish genealogies. It starts by tracing the ancestry of the Grahams of Grayville, Illinois, to Pennsylvania and Virginia. In the course of following their trails to Ireland and Scotland, the author amasses a library of church history, geography, archaeological data, land records, DNA, military and other historical records that stretches as far back as the first recorded Graham in Scotland, William de Graham. This collection of reference data is preserved in the appendices to assist researchers of Scots-Irish ancestry, not just Grahams. Our Grahams of Pennsylvania and Virginia also includes information on related clans such as the Kirkpatricks, Corries, Murrays, and Armstrongs and provides a new perspective on Scottish history and the origin of the Scottish people using the latest Y-DNA and archaeological data available. It breaks new ground and punctures some long-held misconceptions of family genealogies. It also postulates theories that would explain the facts and circumstances behind several major events, as well as family connections, and legends of Scottish history. Additional DNA testing may eventually prove which theories are correct. Our Grahams of Pennsylvania and Virginia contains a treasure of reference material that can be used by researchers of all levels. It is meticulously researched, fully sourced, and provides access information for almost all source material.
The purpose of this book is to bring together current scientific understanding of wetting behaviour that has been gained from theoretical models and quantitative experimental observations. The materials considered are liquid metals or inorganic glasses in contact with solid metals or ceramics at temperatures of 200-2000oC. Wetting has been a significant scientific concern for the last two centuries and reference will be made to classical work by nineteenth century scientists such as Dupré, Laplace and Young that was validated by observations of the behaviour of chemically inert ambient temperature systems. In attempting to achieve the aims of the book, the text has been divided into ten Chapters that can be grouped into four stages of presentation. The first stage comprises two Chapters that review established and newly developed models for their relevance to wetting behaviour at high temperatures, including recent models that encompass the role of chemical reactions at the solid/liquid interfaces. Attention is paid both to equilibrium wetting behaviour (Chapter 1) and to the factors that control the approach to equilibrium (Chapter 2). Then follow Chapters concerned with experimental techniques for scientific measurement of the extent of wetting (Chapter 3) and with the surface energy data for both metals and non-metals that are essential for quantitative interpretation of wetting behaviour (Chapter 4). Descriptions of experimentally determined and quantified wetting behaviour are presented and interpreted in the third part comprising five Chapters dealing with the characteristics of metal/metal, metal/oxide, metal/non-oxide, metal/carbon and molten glass/solid systems. The book concludes with a Chapter commenting on the role of wetting behaviour in joining similar and dissimilar materials by liquid route techniques.
Originally published in 1938, this book is an attempt to present a study of eighteenth-century elementary education, not as the history of educational ideas, nor as the history of administration, in which two garbs the history of the history of education usually appears, but as the study of a neglected aspect of social history. Its main interest lies in the different reactions of philanthropic men and women in England, Scotland, Ireland and Wales to the movement for establishing schools on a religious basis for the children of the poor.
Orphan Island is a historical novel about the island of Cyprus. Revolution, foreign intrigue, intervention, and intercommunal strife are the elements that make up the island's tragedy. Squeezed in the vise of East-West power politics during the cold war, Cyprus becomes the apple of discord as against the will of its people NATO tries to pull the non-aligned island into its camp and make it an unsinkable nuclear base. Through diabolical schemes and stratagems from governments of powerful nations, the island suffers a brutal invasion by the Turks, complete with ferocious atrocities, all in full view of a "freedom-loving NATO." Amid deep hostility, turmoil, espionage, treachery, and war, the love of Achilles and Daphne is rekindled and flourished. Achilles, an idealist intellectual and zealous fighter for freedom, is one of the leaders in the revolution to kick the British out of Cyprus. Artistic Daphne is sensitive and emotional, and she lives to love Achilles and to dream an eternal life with him. But their love follows the intricate weave of their destiny, which is interlaced with the destiny of Cyprus as it is ordained by foreign governments and men with depraved causes. Orphan Island is based on the true story of Cyprus and its courageous people, who ask to be free and because of that their lives change forever, the result of outworn British colonial mentality, and corrupt American foreign policy and failure.
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