Calculation of resonance neutron absorption in two-region problems /the GAROL code/

GAROL computer program explicitly takes into account those effects which arise from neutron resonance overlap of an individual resonance absorber and of mixtures of different resonance absorbers. GAROL computes effective group cross-sections for the resolved resonances of a mixture of isotopes in a two-region cell

Gamma-ray Burst Positions from the ASM on RXTE

The RXTE/ASM has detected and positioned 14 confirmed GRB bursts (at this writing, Jan. 1999) including six whose positions were comunicated to the community 2 to 32 hours after the burst. Two of these latter bursts led to measurements of optical red shifts but one, despite an easily detected x-ray afterglow, produced no detectable optical or radio afterglow.Comment: 2 pages, 1 Figure, A&A format, accepted to appear in the proceedings of the conference "Gamma-Ray Bursts in the Afterglow Era", Rome, 3-6 Nov, 199

The Secondary Star in Cataclysmic Variables and Low Mass X-ray Binaries

We critically re-examine the available data on the spectral types, masses and radii of the secondary stars in cataclysmic variables (CVs) and low-mass X-ray binaries (LMXBs), using the new catalogue of Ritter & Kolb (1998) as a starting point. We find there are 55 reliable spectral type determinations and only 14 reliable mass determinations of CV secondary stars (10 and 5, respectively, in the case of LMXBs). We derive new spectral type-period, mass-radius, mass-period and radius-period relations, and compare them with theoretical predictions. We find that CV secondary stars with orbital periods shorter than 7-8 hours are, as a group, indistinguishable from main sequence stars in detached binaries. We find it is not valid, however, to estimate the mass from the spectral type of the secondary star in CVs or LMXBs. We find that LMXB secondary stars show some evidence for evolution, with secondary stars which are slightly too large for their mass. We show how the masses and radii of the secondary stars in CVs can be used to test the validity of the disrupted magnetic braking model of CV evolution, but we find that the currently available data are not sufficiently accurate or numerous to allow such an analysis. As well as considering secondary star masses, we also discuss the masses of the white dwarfs in CVs, and find mean values of M_1 = 0.69+/-0.13 M_sun below the period gap, and M_1 = 0.80+/-0.22 M_sun above the period gap.Comment: 18 pages, 5 figure

Ephedrine requirements are reduced during spinal anaesthesia for caesarean section in preeclampsia

Part of the Portfolio Thesis by Geoffrey H. Sharwood-Smith: The inferior vena caval compression theory of hypotension in obstetric spinal anaesthesia: studies in normal and preeclamptic pregnancy, a literature review and revision of fundamental concepts, available at http://hdl.handle.net/10023/1815Background: Despite controversy over the haemodynamically safest blockade for caesarean section in women with severe preeclampsia, an increasing number of anaesthetists now opt for spinal anaesthesia. In a previous study we found that spinal compared to epidural anaesthesia offered an equally safe but more effective option for these patients. The current study was designed to compare the hypotension induced by spinal anaesthesia, as measured by ephedrine requirement, between 20 normotensive and 20 severely preeclamptic but haemodynamically stabilised women. Method: Standardised spinal anaesthesia was instituted and ephedrine was given in boluses of 6 mg if the systolic pressure fell >20% from the baseline, or if the patient exhibited symptoms of hypotension. Results: The mean ephedrine requirement of the normotensive group (27.9 ± 11.6 mg) was significantly greater (P < 0.01) than that of the preeclamptic group (16.4 ± 15.0 mg). Conclusion: This suggests that the hypotension induced by spinal anaesthesia in women with severe but haemodynamically stabilised preeclampsia, is less than that of normotensive patients.Publisher PD

Probing the Phase-Dependent Conductance and Nonequilibrium Properties of Josephson Junctions by Means of Flux Entry into Weakly Closed Loops

Numerical simulations have shown that the relative number of flux quanta which penetrate a weakly closed superconducting loop depends upon the magnitude and sign of the phase-dependent conductance. We examine the possible use of this dependence as an experimental probe of the cosy term and nonequilibrium properties of Josephson junctions

Exploring knowledge exchange: a useful framework for practice and policy

Knowledge translation is underpinned by a dynamic and social knowledge exchange process but there are few descriptions of how this unfolds in practice settings. This has hampered attempts to produce realistic and useful models to help policymakers and researchers understand how knowledge exchange works. This paper reports the results of research which investigated the nature of knowledge exchange. We aimed to understand whether dynamic and fluid definitions of knowledge exchange are valid and to produce a realistic, descriptive framework of knowledge exchange. Our research was informed by a realist approach. We embedded a knowledge broker within three service delivery teams across a large mental health organisation, each of whom was grappling with specific challenges. The knowledge broker participated in the team's problem-solving process and collected observational fieldnotes. We also interviewed the team members. Observational and interview data were analysed quantitatively and qualitatively in order to determine and describe the nature of the knowledge exchange process in more detail. This enabled us to refine our conceptual framework of knowledge exchange. We found that knowledge exchange can be understood as a dynamic and fluid process which incorporates distinct forms of knowledge from multiple sources. Quantitative analysis illustrated that five broadly-defined components of knowledge exchange (problem, context, knowledge, activities, use) can all be in play at any one time and do not occur in a set order. Qualitative analysis revealed a number of distinct themes which better described the nature of knowledge exchange. By shedding light on the nature of knowledge exchange, our findings problematise some of the linear, technicist approaches to knowledge translation. The revised model of knowledge exchange which we propose here could therefore help to reorient thinking about knowledge exchange and act as a starting point for further exploration and evaluation of the knowledge exchange process

GAROL - A computer program for evaluating resonance absorption including resonance overlap

GAROL computer program for neutron resonance absorptio

HAVE INCENTIVE BASED POLICIES BEEN OVERSOLD?

Comparisons of alternative pollution control instruments over the past thirty years show quite disparate results for seemingly comparable situations. This research demonstrates how the magnitude of the estimated cost savings associated with incentive-based instruments is influenced by two important factors: (i) separability assumptions between emissions and output, and (ii) participation criteria.Environmental Economics and Policy,

PRICE, QUALITY, AND PESTICIDE RELATED HEALTH RISK CONSIDERATIONS IN FRUIT AND VEGETABLE PURCHASES: AN HEDONIC ANALYSIS OF TUCSON, ARIZONA SUPERMARKETS

National opinion polls indicate that pesticide residues on fresh fruits and vegetables remain an important concern of American consumers, despite a decade-long increase in per capita consumption levels for fresh fruits and vegetables. Increased availability of organically grown fruits and vegetables may change consumer produce purchase behavior which is often dominated by appearance considerations. Domestic consumers likely consider and tradeoff price, visual appearance, and health risk when buying fresh produce. This paper uses an hedonic framework to examine price, appearance, and health risk considerations made by Tucson, Arizona shoppers in 1994.Consumer/Household Economics, Demand and Price Analysis,