689 research outputs found
Identical physicochemical properties of three soluble HL-A substances from human liver or spleen.
No full textA new perspective on population aging
No full textIn Sanderson and Scherbov (2005) we introduced a new forward-looking definition of age and argued that its use, along with the traditional backward-looking concept of age, provides a more informative basis upon which to discuss population aging. Age is a measure of how many years a person has already lived. In contrast, our new approach to measuring age is concerned about the future. In this paper, we first explore our new age measure in detail and show, using an analytic formulation, historical data, and forecasts, that it is, in most cases, insensitive to whether it is measured using period or cohort life tables. We, then, show, using new forward-looking definitions of median age and the old age dependency ratio, how combining the traditional age concept and our new one enhances our understanding of population aging.age/aging, historical demography, life expectancy, median age, population forecasting, prospective age
Interferon, β-2-microglobulin and immunoselection in the pathway to malignancy. A blinkered view from Nag's Head Yard
No full textRecent clinical studies suggest that benign tumour cells express MHC class-I antigens while malignant cells with the same tissue origin do not. Interferons induce normal cells to increase the expression of class-I antigens but Arnold Sanderson and Peter Beverley argue here that malignant cells may not respond in this way. As a result, they may lack the antigens that would make them vulnerable to immune mechanisms dependent on T cells which recognize class-I self-MHC antigens. © 1983
Park County inventory of critical biological resources: final report
No full textIncludes bibliographical references.April 2001.Prepared by Susan Spackman, Denise Culver, and John Sanderson; prepared for: Park County
Aspects of hybrid inflation in supersymmetry
No full textDetails of the hybrid inflation scenario have been studied in the context of the standard non-supersymmetric hybrid potential, its (F-term) SUSY form, and its role within a specific SUSY model, the #phi#NMSSM. A particularly appealing variant of the standard hybrid mechanism, inverted hybrid inflation, is found to be unnatural, requiring coupling constants in the potential < or approx. 10-12. It is also very difficult to achieve a SUSY model of inverted hybrid inflation with one suggested superpotential leading to a potential unbounded from below. The #phi#NMSSM provides a realistic SUSY model capable of both hybrid and inverted hybrid inflation and we study the effects of preheating in this model and the general SUSY case. A particular behaviour is found to result, characteristic of the SUSY version of hybrid inflation, whereby there exists only one natural frequency of coherent classical field oscillations leading to extremely efficient particle production of the homogeneous fields. An analytical study of the parametric amplification via the Mathieu equation is found where the solutions depend on time, tracing a trajectory over each classical field oscillation through the instability chart and confirming the numerical results obtained. Production of axions is model dependent, but in the #phi#NMSSM the dangerously amplified production which would occur considering the fields separately is sufficiently suppressed by proper inclusion of the mixing between the fields. The enormous numbers of the classical fields produced serve to shut off further production, quickly ending the preheating process via back reaction effects, thus leaving the axions safely within experimental bounds and the #phi#NMSSM a viable model. (author)Available from British Library Document Supply Centre-DSC:DXN029901 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
A natural heritage assessment of wetlands and riparian areas in Summit County, Colorado: 1997 final report
No full textIncludes bibliographical references.December 1997.Prepared for: Colorado Dept. of Natural Resources; prepared by: Denise R. Culver and John Sanderson
Decline in firing technology or poorer fuel resources? High-temperature thermoluminescence (HTTL) archaeothermometry of Neolithic ceramics from Pool, Sanday, Orkney
No full textThe Neolithicceramic assemblage from the multi-period coastal settlement at Pool on the island of Sanday, Orkney is unique because it stratigraphically spans both the earlier round-based (including possible Unstan bowls) and later flat-based (‘Grooved Ware’) traditions. High-temperaturethermoluminescence (HTTL) analysis objectively demonstrates that ceramics from the earliest Neolithic layers have been consistently better fired compared to examples from later layers. We suggest two interpretations of these data: either firingtechnology declined with changing social structures and/or adoption of a different ceramic tradition or that there was greater pressure on fuel resource and management in the later Neolithic. Paleoenvironmental and chronological evidence indicate climatic deterioration in the later Neolithic, which adds further support to an interpretation of a poorerfuel resource at that time. In addition to studies of the HTTL signal, analysis of the ambient temperature modification of the TL signal has potential to support or evaluate dating evidence, and is readily applicable to optically stimulated luminescence (OSL) age data
Plants, People and Practices: The Nature and History of the UPOV Convention
No full textThe International Union for the Protection of New Varieties of Plants (UPOV) and the UPOV Convention are increasingly relevant and important. They have technical, social and normative legitimacy and have standardised numerous concepts and practices related to plant varieties and plant breeding. In this book, Jay Sanderson provides the first sustained and detailed account of the Convention. Building upon the idea that it has an open-ended and contingent relationship with scientific, legal, technical, political, social and institutional actors, the author explores the Convention's history, concepts and practices. Part I examines the emergence of the UPOV Convention during the 1950s and its expanding legitimacy in relation to plant variety protection. Part II explores the Convention's key concepts and practices, including plant breeder, plant variety, plant names (denomination), characteristics, protected material, essentially derived varieties (EDV) and farm saved seed (FSS). This book is an invaluable resource for academics, policy makers, agricultural managers and researchers in this field
Extreme rich fens of South Park, Colorado: their distribution, identification, and natural heritage significance
No full textprepared for: Park County, the Colorado Department of Natural Resources, and the U.S. Environmental Protection Agency ... by John Sanderson and Margaret March.July 30, 1996.Includes bibliographical references (pages 24-27)
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