This book presents an up-to-date review concerning acetylcholine, a messenger substance which is produced transiently in practically all living organisms, from bacteria to human beings. High acetylcholine concentrations have been encountered in growing parts of plants, in the royal jelly of bees, and in the human placenta. In vertebrates, many non-neuronal cells, such as epithelial cells, endothelial cells, immune cells or spermatozoids, secrete acetylcholine in response to specific signals. Acetylcholine is better known as a neurotransmitter substance, supporting synaptic transmission in the central and autonomic nervous systems. Transmission in these places is a point-to-point process which is relatively rapid and shows many anatomical and physiological variations, according to synapses and animal species. Much more rapid is transmission in giant and specialised synapses, such as the neuromuscular junctions and their homologues, in the electric organs of certain fish. The mechanisms of acetylcholine release in these ultra-rapid junctions have been revisited in recent decades and the picture has completely changed. As the book shows, acetylcholine signalling (also called cholinergic signalling) is of particular physiological and toxicological importance, since it can be perturbed by many natural or synthetic substances.
This book presents an up-to-date review concerning acetylcholine, a messenger substance which is produced transiently in practically all living organisms, from bacteria to human beings. High acetylcholine concentrations have been encountered in growing parts of plants, in the royal jelly of bees, and in the human placenta. In vertebrates, many non-neuronal cells, such as epithelial cells, endothelial cells, immune cells or spermatozoids, secrete acetylcholine in response to specific signals. Acetylcholine is better known as a neurotransmitter substance, supporting synaptic transmission in the central and autonomic nervous systems. Transmission in these places is a point-to-point process which is relatively rapid and shows many anatomical and physiological variations, according to synapses and animal species. Much more rapid is transmission in giant and specialised synapses, such as the neuromuscular junctions and their homologues, in the electric organs of certain fish. The mechanisms of acetylcholine release in these ultra-rapid junctions have been revisited in recent decades and the picture has completely changed. As the book shows, acetylcholine signalling (also called cholinergic signalling) is of particular physiological and toxicological importance, since it can be perturbed by many natural or synthetic substances.
Since its birth with the creation of the international Red Cross in 1863, international humanitarian assistance has developed considerably since World War II. In accordance with the Red Cross principle of humanity, it aims at preventing and alleviating human suffering wherever it may be found, protecting life and health and ensuring respect for the human being. International humanitarian assistance involves a complex network of government agencies, intergovernmental and non-governmental organizations, and individual volunteers: it has been labelled a `non-system'. While governments and intergovernmental organizations play a dominant and structured role in this field, the non-governmental organizations and their volunteers have proved to be their necessary operational partners, providing material, medical and moral relief and care wherever it may be needed, beyond borders, at the grassroots level. Following a brief review of recent humanitarian activities of intergovernmental organizations, and an analysis of current trends of voluntarism, this book focuses on the role, status and attitudes of the major humanitarian non-governmental organizations, including the Red Cross organizations, the British charities, Church-related agencies, medical volunteers (such as the `French Doctors') and U.N. volunteers. Should humanitarian non-governmental organizations provide relief assistance with the Red Cross concern for discretion, neutrality and impartiality? Or should they bear witness and denounce publicly human rights violations, at the risk of being expelled from recipient countries and having to stop their assistance? The controversial claim of a `right' to receive and a `duty' to provide humanitarian assistance beyond borders is also addressed, as well as the possible need for a status to be accorded to international volunteers.
After two centuries during which it had nearly disappeared in Western countries, sortition is used again as a method of selecting people who could speak for, and in certain cases decide for, all the citizenry. What is the meaning of this comeback? To answer this question, this book offers a historical analysis. It brings together a number of the best specialists on political sortition from antiquity to contemporary experiments, in Europe but also in the Ancient Middle East and in imperial China. With a transdisciplinary perspective, this volume demonstrates that sortition has been a crucial device in political history; that the instruments and places where sortition was practised matter for the understanding of the social and political logics at stake; and that these logics have been quite different, random selection being sometimes an instrument of radical democracy and in other contexts a tool for solving conflicts among elites. Will sortition in politics helps to democratize democracy in the twenty-first century?
Applied Micromechanics of Complex Microstructures explains the fundamental concepts of continuum modeling of various complicated microstructures, covering nanocomposites, multiphase composites, biomaterials, biological materials, and more. The authors outline the calculation of effective mechanical and thermal properties, allowing readers to understand the step-by-step modeling and homogenization of complicated microstructures, and the book also features a chapter on microstructure hull and material design. Modeling of complex samples with nonlinear properties such as neural tissue, bone microstructure, and liver tissue is also explained and analyzed. Explains the core concepts of continuum modeling of different complex microstructures, including nanocomposites, multiphase composites, biomaterials, and biological materials Provides detailed calculations of eff ective mechanical and thermal properties allowing the audience to understand the modeling and homogenization of complex microstructures Covers several methods for designing the microstructure of heterogeneous materials
Thank you for visiting our website. Would you like to provide feedback on how we could improve your experience?
This site does not use any third party cookies with one exception — it uses cookies from Google to deliver its services and to analyze traffic.Learn More.