11,087 research outputs found
Radiation protection guidelines for space missions
NASA's current radiation protection guidelines date from 1970, when the career limit was set at 400 rem. Today, using the same approach, but with the current risk estimates, a considerably lower career limit would obtain. Also, there is considerably more information about the radiation environments to be experienced in different missions than previously. Since 1970 women have joined the ranks. For these and other reasons it was necessary to reexamine the radiation protection guidelines. This task was undertaken by the National Council on Radiation Protection and Measurements Scientific Committee 75 (NCRP SC 75). Below the magnetosphere the radiation environment varies with altitude and orbit inclination. In outer space missions galactic cosmic rays, with the small but important heavy ion component, determine the radiation environment. The new recommendations for career dose limits, based on lifetime excess risk of cancer mortality, take into account age at first exposure and sex. The career limits range from 100 rem (4.0Sv) for a 24 year old female to 400 rem for a 55 year old male compared to the previous single limit of 400 rem (4.0 Sv). The career limit for the lens of the eye was reduced from 600 to 400 rem (6.0 to 4.0 Sv.
QED in strong, finite-flux magnetic fields
Lower bounds are placed on the fermionic determinants of Euclidean quantum
electrodynamics in two and four dimensions in the presence of a smooth,
finite-flux, static, unidirectional magnetic field , where
or , and is a point in the xy-plane.Comment: 10 pages, postscript (in uuencoded compressed tar file
Foot-operated cell-counter
Cell-counter for cell indices consists of a footboard with four pressure sensitive switches and an enclosure for the components and circuitry. This device increases the operators efficiency by reducing the number of required hand movements
Fermion Determinants
The current status of bounds on and limits of fermion determinants in two,
three and four dimensions in QED and QCD is reviewed. A new lower bound on the
two-dimensional QED determinant is derived. An outline of the demonstration of
the continuity of this determinant at zero mass when the background magnetic
field flux is zero is also given.Comment: 10 page
Senior olympians' achievement goals and motivational responses
Journal ArticleThe purpose of this study was to examine the motivational perspectives of athletes participating in the Senior Olympic Games. One hundred thirty-seven senior athletes (54 males, 82 females, and 1 nonidentifier) completed measures of goal orientations, beliefs about the causes of success in sport, intrinsic motivation, and views about the purpose of sport. Multivariate analysis revealed a positive association between task orientation and intrinsic motivation, the belief that success in sport is achieved through hard work, and self-improvement-based purposes of sport. In contrast, ego orientation was associated with the belief that success in sport is achieved by those who are gifted with natural ability and who know how to maximize external and deceptive factors. Further, ego orientation was linked to the belief that the purpose of sport was for personal gain. The motivational implications of the present findings are discussed based on the tenets of goal perspective theor
Baryogenesis via lepton number violating scalar interactions
We study baryogenesis through lepton number violation in left-right symmetric
models. In these models the lepton number and CP violating interactions of the
triplet higgs scalars can give rise to lepton number asymmetry through
non-equilibrium decays of the triplet higgs and the right handed
neutrinos. This in turn generates baryon asymmetry during the electroweak
anomalous processes.Comment: 14 pages, UTPT-93-1
Exploring how nurses assess, monitor and manage acute pain for adult critically ill patients in the emergency department: Protocol for a mixed methods study
© 2017 The Author(s). Background: Many critically ill patients experience moderate to severe acute pain that is frequently undetected and/or undertreated. Acute pain in this patient cohort not only derives from their injury and/or illness, but also as a consequence of delivering care whilst stabilising the patient. Emergency nurses are increasingly responsible for the safety and wellbeing of critically ill patients, which includes assessing, monitoring and managing acute pain. How emergency nurses manage acute pain in critically ill adult patients is unknown. The objective of this study is to explore how emergency nurses manage acute pain in critically ill patients in the Emergency Department. Methods: In this paper, we provide a detailed description of the methods and protocol for a multiphase sequential mixed methods study, exploring how emergency nurses assess, monitor and manage acute pain in critically ill adult patients. The objective, method, data collection and analysis of each phase are explained. Justification of each method and data integration is described. Discussion: Synthesis of findings will generate a comprehensive picture of how emergency nurses' perceive and manage acute pain in critically ill adult patients. The results of this study will form a knowledge base to expand theory and inform research and practice
Failure of the Standard Coupled-Channels Method in Describing the Inelastic Reaction Data: On the Use of a New Shape for the Coupling Potential
We present the failure of the standard coupled-channels method in explaining
the inelastic scattering together with other observables such as elastic
scattering, excitation function and fusion data. We use both microscopic
double-folding and phenomenological deep potentials with shallow imaginary
components. We argue that the solution of the problems for the inelastic
scattering data is not related to the central nuclear potential, but to the
coupling potential between excited states. We present that these problems can
be addressed in a systematic way by using a different shape for the coupling
potential instead of the usual one based on Taylor expansion.Comment: 10 pages, 4 figures, 1 table, Latex:RevTex4 published in J. Phys. G:
Nucl. Part. Phy
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