This report considers the biological and behavioral mechanisms that may underlie the pathogenicity of tobacco smoke. Many Surgeon General's reports have considered research findings on mechanisms in assessing the biological plausibility of associations observed in epidemiologic studies. Mechanisms of disease are important because they may provide plausibility, which is one of the guideline criteria for assessing evidence on causation. This report specifically reviews the evidence on the potential mechanisms by which smoking causes diseases and considers whether a mechanism is likely to be operative in the production of human disease by tobacco smoke. This evidence is relevant to understanding how smoking causes disease, to identifying those who may be particularly susceptible, and to assessing the potential risks of tobacco products.

Gretchen Krueger's poignant narrative explores how doctors, families, and the public interpreted the experience of childhood cancer from the 1930s through the 1970s. Pairing the transformation of childhood cancer from killer to curable disease with the personal experiences of young patients and their families, Krueger illuminates the twin realities of hope and suffering. In this social history, each decade follows a family whose experience touches on key themes: possible causes, means and timing of detection, the search for curative treatment, the merit of alternative treatments, the decisions to pursue or halt therapy, the side effects of treatment, death and dying—and cure. Recounting the complex and sometimes contentious interactions among the families of children with cancer, medical researchers, physicians, advocacy organizations, the media, and policy makers, Krueger reveals that personal odyssey and clinical challenge are the simultaneous realities of childhood cancer. This engaging study will be of interest to historians, medical practitioners and researchers, and people whose lives have been altered by cancer.

This volume from The NASA History Series presents an overview of the science of hypersonics, the study of flight at speeds at which the physics of flows is dominated by aerodynamic heating. The survey begins during the years immediately following World War II, with the first steps in hypersonic research: the development of missile nose cones and the X-15; the earliest concepts of hypersonic propulsion; and the origin of the scramjet engine. Next, it addresses the re-entry problem, which came to the forefront during the mid-1950s, showing how work in this area supported the manned space program and contributed to the development of the orbital shuttle. Subsequent chapters explore the fading of scramjet studies and the rise of the National Aerospace Plane (NASP) program of 1985–95, which sought to lay groundwork for single-stage vehicles. The program's ultimate shortcomings — in terms of aerodynamics, propulsion, and materials — are discussed, and the book concludes with a look at hypersonics in the post-NASP era, including the development of the X-33 and X-34 launch vehicles, further uses for scramjets, and advances in fluid mechanics. Clearly, ongoing research in hypersonics has yet to reach its full potential, and readers with an interest in aeronautics and astronautics will find this book a fascinating exploration of the field's history and future.

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