Ocean dynamics of outer solar system satellites

Ocean worlds are prevalent in the solar system. Focusing on Enceladus, Titan, Europa, and Ganymede, I use rotating convection theory and numerical simulations to predict ocean currents and the potential for ice-ocean coupling. When the influence of rotation is relatively strong, the oceans have multiple zonal jets, axial convective motions, and most efficient heat transfer at high latitudes. This regime is most relevant to Enceladus and possibly to Titan, and may help explain their long-wavelength topography. For a more moderate rotational influence, fewer zonal jets form, Hadley-like circulation cells develop, and heat flux peaks near the equator. This regime is predicted for Europa, where it may help drive geologic activity via thermocompositional diapirism in the ice shell, and is possible for Titan. Weak rotational influence allows concentric zonal flows and overturning cells with no preferred orientation. Predictions for Ganymede's ocean span multiple regimes

Towards panel data specifications of efficiency measures for English acute hospitals

This paper reports work undertaken for the Department of Health to explore different approaches of measuring hospital efficiency. The emphasis throughout is on developing adjusted cost-efficiency measures in line with NHS Trusts performance objectives. Previous work described the derivation of three residual-based cost indices (CCI, 2CCI and 3CCI), each with increasing adjustment in terms of case mix, factor prices and environmental factors for a single year’s data (1995/6) (Söderlund & van der Merwe, 1999). This study explores further options based on the previous work by: (1) supplementing hospital level with specialty level data; (2) studying a 4-year panel from 1994/5 to 1997/8; (3) estimating models with non-symmetric error terms and including Trust-specific effects when measuring inefficiency. Although the paper argues that panel data models may have certain advantages over cross-sectional ones, the results suggest that data pooling across years provide robust parameter estimates. Longitudinal fixed effect models may however be useful to construct efficiency indices while stochastic frontier models have the advantage of taking account of random noise. Specialty level models proved inferior to whole hospital estimations. The paper argues that the degree of variation between hospitals in terms of efficiency is not that great and scope for efficiency enhancement is primarily attainable by optimising capacity and activity levels in the long run. Increased activity levels may however have adverse consequences such as increased hospital infection rates, poorer quality of care and a lack of capacity to deal with emergency demand. The paper argues that the Department of Health might consider a shift from the adjusted cost index approach used in this normative benchmarking framework to the more conventional efficiency analysis approach using a total cost function, and more flexible functional forms, allowing for a more defensible interpretation of the residuals as inefficiency.efficiency

Hospital benchmarking analysis and the derivation of cost indices

This paper reports work undertaken for the UK Department of Health to explore approaches to measuring and comparing hospital productivity. The purpose of the cost indices produced in this paper has been to use them to derive productivity scores for English NHS Trusts in order to benchmark them against one another to help identify poorer performers. The work builds on previous deterministic ‘efficiency indices’ by using statistical regression adjustment techniques. This work describes the derivation of three cost indices (CCI, 2CCI and 3CCI), each with increasing adjustment in terms of case mix, factor prices and environmental factors. The analysis uses data for the year 1995/6 and specifically examines acute Trusts. The CCI cost index is a deterministic index that takes into account case mix as measured by Healthcare Resource Groups (HRGs) and inpatient, first outpatient and accident and emergency (A & E) activity. It is a weighted index of actual / expected costs where expected costs are measured as average national costs per respective attendance. 2CCI takes factors into account such as additional adjustments for case mix, age and gender mix, transfers in and out of the hospital, inter-specialty transfers, local labour and capital prices and teaching and research costs for which Trusts might be over or under compensated. The 3CCI makes additional adjustments over and above those in the 2CCI for hospital capacity, including number of beds, and number of sites, scale of inpatient and non-inpatient activity and scope of activity. It therefore tries to capture institutional characteristics amenable to change in the long, but not the short run. 2CCI and 3CCI indices are obtained from a short-run regression model using CCI as the dependent variable, and productivity scores are obtained from the residuals of the regressions. The results suggest that the statistical adjustments reduce estimates of productivity variation between providers considerably, such that there is relatively little difference between providers in terms of fully adjusted (short-run) productivity scores (3CCI). This suggests that savings from bringing poorer performers up to those with higher productivity scores, may in fact be quite small. In the long run there may be more scope for productivity enhancement and savings than in the short run, by optimising capacity and activity levels. Productivity benchmarking results should always be tempered against judgements on the quality and effectiveness of service provision which these indices are currently unable to measure. Implicitly equating high cost to inefficiency, as these indices do, may also be problematic. The paper suggests that the use of panel data and the application of alternative methodologies (such as stochastic frontiers and Data Envelopment Analysis) would be a valuable way to extend this work.cost index, productivity

Different effects of adding white noise on cognitive performance of sub-, normal and super-attentive school children

Objectives: Noise often has detrimental effects on performance. However, because of the phenomenon of stochastic resonance (SR), auditory white noise (WN) can alter the "signal to noise'' ratio and improve performance. The Moderate Brain Arousal (MBA) model postulates different levels of internal "neural noise'' in individuals with different attentional capacities. This in turn determines the particular WN level most beneficial in each individual case-with one level of WN facilitating poor attenders but hindering super-attentive children. The objective of the present study is to find out if added WN affects cognitive performance differently in children that differ in attention ability. Methods: Participants were teacher-rated super-(N = 25); normal-(N = 29) and sub-attentive (N = 36) children (aged 8 to 10 years). Two non-executive function (EF) tasks (a verbal episodic recall task and a delayed verbal recognition task) and two EF tasks (a visuo-spatial working memory test and a Go-NoGo task) were performed under three WN levels. The non-WN condition was only used to control for potential differences in background noise in the group testing situations. Results: There were different effects of WN on performance in the three groups-adding moderate WN worsened the performance of super-attentive children for both task types and improved EF performance in sub-attentive children. The normal-attentive children's performance was unaffected by WN exposure. The shift from moderate to high levels of WN had little further effect on performance in any group. Significance: The predicted differential effect of WN on performance was confirmed. However, the failure to find evidence for an inverted U function challenges current theories. Alternative explanations are discussed. We propose that WN therapy should be further investigated as a possible non-pharmacological treatment for inattention

Molecular mechanisms of pyrethroid insecticide neurotoxicity: recent advances

Synthetic pyrethroid insecticides were introduced into widespread use for the control of insect pests and disease vectors more than three decades ago. In addition to their value in controlling agricultural pests, pyrethroids are at the forefront of efforts to combat malaria and other mosquito-borne diseases and are also common ingredients of household insecticide and companion animal ectoparasite control products. The abundance and variety of pyrethroid uses contribute to the risk of exposure and adverse effects in the general population. The insecticidal actions of pyrethroids depend on their ability to bind to and disrupt voltage-gated sodium channels of insect nerves. Sodium channels are also important targets for the neurotoxic effects of pyrethroids in mammals but other targets, particularly voltage-gated calcium and chloride channels, have been implicated as alternative or secondary sites of action for a subset of pyrethroids. This review summarizes information published during the past decade on the action of pyrethroids on voltage-gated sodium channels as well as on voltage-gated calcium and chloride channels and provides a critical re-evaluation of the role of these three targets in pyrethroid neurotoxicity based on this informatio

Data Gaps in Evidence-Based Research on Small Water Enterprises in Developing Countries

This paper assess the literature on small water enterprises -- water delivery operations that predominantly provide water at the community level. A research agenda is recommended to advance knowledge on effective SWE service

Knockdown Resistance to DDT and Pyrethroids in the House Fly (Diptera: Muscidae): From Genetic Trait to Molecular Mechanism

Knockdown resistance to DDT and pyrethrins was the 1st insecticide resistance trait involving reduced target site sensitivity to be identified and isolated genetically. Almost 5 decades later, knockdown resistance continues to threaten the continued effectiveness of pyrethroid insecticides in the control of numerous agricultural pests and vectors of human disease. In this review we summarize progress in the characterization of knockdown resistance in the house fly, Musca domestica L., culminating in the identification of the specific sodium channel gene mutations that cause the reduced neuronal sensitivity to DDT and pyrethroids in knockdown-resistant insect

La presse et la politique étrangère canadienne

This article reports on the findings of what appears to be the first content analysis of all aspects of Canadian press coverage of Canadian foreign relations. Six major/newspapers were chosen on the basis of national significance and linguistic and regional considerations: the Halifax Chronicle-Herald, Le Devoir (Montréal), La Presse (Montréal), the Ottawa Citizen, the Toronto Globe and Mail and the Vancouver Sun. During the period studied (the last quarter of 1982), these newspapers averaged nearly nine items per issue on Canadian foreign relations and relied predominantly on Canadian sources for their material. However, there was a relative lack of analytic coverage and only a limited number of items that adopted supportive or critical positions on the various issues in Canadian foreign policy. Commercial matters received both the most extensive and the most sophisticated treatment, while the reporting of political subjects was generally less detailed and often superficial. In terms of relationships, that with the United States was arguably the only one to receive adequate coverage, while from the standpoint of issues there were several that received insufficient attention, such an environmental problems in relations with the United States, Canadian concerns at the United Nations, and international developmental matters. One of the most notable differences in coverage among the papers studied was the variation found in the attention paid to the international role of Quebec, which received only scant attention in the English-language press but was the single most frequently coded theme in the Quebec newspapers. While analytic coverage was found to be more extensive and profound in the Globe and Mail, Le Devoir and La Presse than in the other three papers, the authors in general agree with De Montigny Marchand that Canadian newspapers are "an uncertain intellectual force in the definition and interpretation of Canadian foreign policy"

Managing and temporality

This special issue is the third in the Scandinavian Journal of Management (SJM) to focus exclusively on the processual nature of managing and organizing. These three special issues offer an approximate genealogy of recent developments in process thinking in the field of management and organization

Qui sont nos ennemis? Qui sont nos amis? La presse pakistanaise et ses perceptions des attitudes et politiques de quatre grandes puissance 1958-1965.

Utilizing content analysis methodology, this paper studies Pakistani press perceptions of external sources of threat and support covering the Period 1958-1965.From the literature on Pakistani foreign policy, seven specific hypotheses are extractedfor testing:1 - during the period 1958-1965, India was perceived to be the major threat toPakistan ;2 - the perception of India as the major threat increased sharply from 1962 onwards;3 - in 1959 China was perceived to be a greater threat to Pakistan than India was;4 - the Soviet Union was perceived to be the major threat in 1958, a significant butsecondary threat in 1959, the main threat again in 1960, and an insignificantthreat from 1961 onwards;5 - at no time during the period 1958-1965 was the United States perceived to be athreat to Pakistan;6 - the respective policies of China, the US.S.R., and the U.S. towards South Asia ingeneral and on the Kashmir issue in particular, played a major part in determiningPakistan's attitudes toward these states;7 - U.S. arms aid to India in 1962 resulted in a major Pakistani disillusionment withthe United States and this was accompanied by more positive Pakistani viewstoward the US.S.R. and China.Our data drawn from front page news stores and editorials appearing in a sample of the Pakistani newspaper Dawn, confirm in general terms hypotheses 1, 2, 5, 6, and 7, but fall to confirm hypotheses 3 and 4.Overall, the data point to the significance of the Sino-Indian border war in the fall of 1962 as a crucial turning point in Pakistan 's foreign policy alignments. Specifically, we see evidence of a turning away from the United States, combined with a movement toward China. Attitudes toward the Soviet Union were ambivalent