Guidelines for international plutonium management: Overview and implications

In September, 1997, nine of the world`s plutonium-using countries agreed to a set of guidelines for international plutonium management, with acceptances to be submitted to the International Atomic Energy Agency on December 1. Following three years of discussion, the guidelines provide a unified package of accepted rules for the storage, handling, and transportation of civil plutonium as well as military plutonium that has been declared as no longer required for defense purposes. New requirements include a formal declaration of national plutonium strategies, which will recognize the environmental, economic, and proliferation concerns and the consequent importance of balancing plutonium supply and demand. Nations will also make annual declaration of their non-military stockpiles of unirradiated plutonium, together with estimates of the plutonium content in spent reactor fuel. These guidelines represent the first formally accepted recognition of the need for plutonium management of this scope and could thus provide a partial basis for future monitoring and policy regimes

Computational information geometry in statistics: foundations

This paper lays the foundations for a new framework for numerically and computationally applying information geometric methods to statistical modelling

Vive les différences? Voice in French MNCs' overseas workplaces: a comparative study of voice in French, German and US subsidiaries in the UK

© 2014, © 2014 Taylor & Francis. Foreign-owned firms help to disseminate management practices across UK companies; this includes the ability of indigenous firms to learn improved human resource management (HRM) practices from leading foreign companies. Analysing the transfer of HRM policies forms an important strand of the international HRM and comparative capitalisms literatures; however, large-scale, comparative studies of voice patterns in German, US and, in particular, French subsidiaries in the UK are limited. This paper draws on a major survey that includes the, to date, largest sample of French MNC subsidiaries. It does not simply identify the existence of different kinds of voice mechanisms, but examines how these different practices come together in the implementation of subsidiaries' voice policies. This enables the detection of subtle, but important, differences in the subsidiaries' voice practices. French subsidiaries are significantly less likely to pursue a partnership approach to voice than their German and US counterparts. French and US establishments are significantly more likely to adopt a ‘bleak house’ approach than German ones. Importantly, these key differences only emerge at a fine-grained level of analysis that examines how subsidiaries implement voice practices

Efficacy and Safety of Three Antiretroviral Regimens for Initial Treatment of HIV-1: A Randomized Clinical Trial in Diverse Multinational Settings

Background:Antiretroviral regimens with simplified dosing and better safety are needed to maximize the efficiency of antiretroviral delivery in resource-limited settings. We investigated the efficacy and safety of antiretroviral regimens with once-daily compared to twice-daily dosing in diverse areas of the world.Methods and Findings:1,571 HIV-1-infected persons (47% women) from nine countries in four continents were assigned with equal probability to open-label antiretroviral therapy with efavirenz plus lamivudine-zidovudine (EFV+3TC-ZDV), atazanavir plus didanosine-EC plus emtricitabine (ATV+DDI+FTC), or efavirenz plus emtricitabine-tenofovir-disoproxil fumarate (DF) (EFV+FTC-TDF). ATV+DDI+FTC and EFV+FTC-TDF were hypothesized to be non-inferior to EFV+3TC-ZDV if the upper one-sided 95% confidence bound for the hazard ratio (HR) was ≤1.35 when 30% of participants had treatment failure.An independent monitoring board recommended stopping study follow-up prior to accumulation of 472 treatment failures. Comparing EFV+FTC-TDF to EFV+3TC-ZDV, during a median 184 wk of follow-up there were 95 treatment failures (18%) among 526 participants versus 98 failures among 519 participants (19%; HR 0.95, 95% CI 0.72-1.27; p = 0.74). Safety endpoints occurred in 243 (46%) participants assigned to EFV+FTC-TDF versus 313 (60%) assigned to EFV+3TC-ZDV (HR 0.64, CI 0.54-0.76; p<0.001) and there was a significant interaction between sex and regimen safety (HR 0.50, CI 0.39-0.64 for women; HR 0.79, CI 0.62-1.00 for men; p = 0.01). Comparing ATV+DDI+FTC to EFV+3TC-ZDV, during a median follow-up of 81 wk there were 108 failures (21%) among 526 participants assigned to ATV+DDI+FTC and 76 (15%) among 519 participants assigned to EFV+3TC-ZDV (HR 1.51, CI 1.12-2.04; p = 0.007).Conclusion: EFV+FTC-TDF had similar high efficacy compared to EFV+3TC-ZDV in this trial population, recruited in diverse multinational settings. Superior safety, especially in HIV-1-infected women, and once-daily dosing of EFV+FTC-TDF are advantageous for use of this regimen for initial treatment of HIV-1 infection in resource-limited countries. ATV+DDI+FTC had inferior efficacy and is not recommended as an initial antiretroviral regimen.Trial Registration:http://www.ClinicalTrials.gov NCT00084136

Reliability problems in power-generation systems

Some widely publicized incidents have called attention to the problems of reliability, safety, and dependability of power-generation systems, increasing public pressure for additional safety guarantees in power systems. The tendency has been to demand guarantees to zero-risk, an attitude which both augments and is augmented by the slow-growth ethic that has become familiar through the 1970s. It is the suggestion of this discussion paper that, regardless of the merits of different political positions on these issues, it is essential to have a more-precise understanding of the factors that are involved: specifically, that mathematical/statistical tools be developed and made available to potential users in order to quantify the magnitude of the risks inherent in using or failing to use competing technologies. The following are discussed: estimation of very-low-failure probabilities; complex-system reliability methodologies; dependence in failure modes; use of observational-study data; communication of reliability data to nontechnical individuals; semi-parametric procedures; estimating the reliability of man-machine systems; degraded-operation failure modes; pooling data; and accelerated data collection

Predicting low-probability/high-consequence events

PRAs often require quantification of the probabilities of various low-probability events, such as accident-initiating events and hardware-fault events. A two-stage Bayes/empirical Bayes data pooling procedure is presented for use in combining as many as five different types of relevant data. A Poisson model is assumed for the event in question. Empirical Bayes methods are used to determine the population variability curve, while Bayesian methods are used to specialize this curve to the specific event in question. The procedure is illustrated by an example in which we estimate the probability of failure of a hypothetical large dam based on (1) a deductive event-tree-type analysis of the probability, (2) historical US dam failure data, (3) the opinions of a committee of several dam experts, and (4) the operating history for the dam in question. A Stage-2 posterior distribution is produced which incorporates these data sources. Similar distributions are produced for various combinations of data types and used to assess the contribution of each data source

Biaxial loading and shallow-flaw effects on crack-tip constraint and fracture toughness

A program to develop and evaluate fracture methodologies for the assessment of crack-tip constraint effects on fracture toughness of reactor pressure vessel (RPV) steels has been initiated in the Heavy-Section Steel Technology (HSST) Program. Crack-tip constraint is an issue that significantly impacts fracture mechanics technologies employed in safety assessment procedures for commercially licensed nuclear RPVs. The focus of studies described herein is on the evaluation of two stressed-based methodologies for quantifying crack-tip constraint (i.e., J-Q theory and a micromechanical scaling model based on critical stressed volumes) through applications to experimental and fractographic data. Data were utilized from single-edge notch bend (SENB) specimens and HSST-developed cruciform beam specimens that were tested in HSST shallow-crack and biaxial testing programs. Results from applications indicate that both the J-Q methodology and the micromechanical scaling model can be used successfully to interpret experimental data from the shallow- and deep-crack SENB specimen tests. When applied to the uniaxially and biaxially loaded cruciform specimens, the two methodologies showed some promising features, but also raised several questions concerning the interpretation of constraint conditions in the specimen based on near-tip stress fields. Fractographic data taken from the fracture surfaces of the SENB and cruciform specimens are used to assess the relevance of stress-based fracture characterizations to conditions at cleavage initiation sites. Unresolved issues identified from these analyses require resolution as part of a validation process for biaxial loading applications. This report is designated as HSST Report No. 142

Psychotropic drug utilization in Europe: results from the European Study of the Epidemiology of Mental Disorders (ESEMeD) project

Item does not contain fulltextThe ESEMeD/MHEDEA 2000 investigators. Psychotropic drug utilization in Europe: results from the European Study of the Epidemiology of Mental Disorders (ESEMeD) project. Acta Psychiatr Scand 2004: 109 (Suppl. 420): 55-64. © Blackwell Munksgaard 2004. Objective: To assess psychotropic drug utilization in the general population of six European countries, and the pattern of use in individuals with different DSM-IV diagnoses of 12-month mental disorders. Method: Data were derived from the European Study of the Epidemiology of Mental Disorders (ESEMeD/MHEDEA 2000), a cross-sectional psychiatric epidemiological study in a representative sample of 21 425 adults aged 18 or older from six European countries (e.g. Belgium, France, Germany, Italy, the Netherlands and Spain). Individuals were asked about any psychotropic drug use in the past 12 months, even if they used the drug(s) just once. A colour booklet containing high-quality pictures of psychotropic drugs commonly used to treat mental disorders was provided to help respondents recall drug use. Results: Psychotropic drug utilization is generally low in individuals with any 12-month mental disorder (32.6%). The extent of psychotropic drug utilization varied according to the specific DSM-IV diagnosis. Among individuals with a 12-month diagnosis of pure major depression, only 21.2% had received any antidepressants within the same period; the exclusive use of antidepressants was even lower (4.6%), while more individuals took only anxiolytics (18.4%). Conclusion: These data question the appropriateness of current pharmacological treatments, particularly for major depression, in which under-treatment is coupled with the high use of non-specific medications, such as anxiolytics