1,270 research outputs found

    Prodigal Theology for an Anxious Age: A Review of On the Road with Saint Augustine

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    Smith suggests that to be human is to be a refugee, longing for home, never quite being satisfied. Posting about the book On the Road with Saint Augustine from In All Things - an online journal for critical reflection on faith, culture, art, and every ordinary-yet-graced square inch of God’s creation. https://inallthings.org/prodigal-theology-for-an-anxious-age-a-review-of-on-the-road-with-saint-augustine

    Potential for large outbreaks of Ebola virus disease.

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    Outbreaks of Ebola virus can cause substantial morbidity and mortality in affected regions. The largest outbreak of Ebola to date is currently underway in West Africa, with 3944 cases reported as of 5th September 2014. To develop a better understanding of Ebola transmission dynamics, we revisited data from the first known Ebola outbreak, which occurred in 1976 in Zaire (now Democratic Republic of Congo). By fitting a mathematical model to time series stratified by disease onset, outcome and source of infection, we were able to estimate several epidemiological quantities that have previously proved challenging to measure, including the contribution of hospital and community infection to transmission. We found evidence that transmission decreased considerably before the closure of the hospital, suggesting that the decline of the outbreak was most likely the result of changes in host behaviour. Our analysis suggests that the person-to-person reproduction number was 1.34 (95% CI: 0.92-2.11) in the early part of the outbreak. Using stochastic simulations we demonstrate that the same epidemiological conditions that were present in 1976 could have generated a large outbreak purely by chance. At the same time, the relatively high person-to-person basic reproduction number suggests that Ebola would have been difficult to control through hospital-based infection control measures alone

    Bias correction methods for test-negative designs in the presence of misclassification.

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    The test-negative design (TND) has become a standard approach for vaccine effectiveness (VE) studies. However, previous studies suggested that it may be more vulnerable than other designs to misclassification of disease outcome caused by imperfect diagnostic tests. This could be a particular limitation in VE studies where simple tests (e.g. rapid influenza diagnostic tests) are used for logistical convenience. To address this issue, we derived a mathematical representation of the TND with imperfect tests, then developed a bias correction framework for possible misclassification. TND studies usually include multiple covariates other than vaccine history to adjust for potential confounders; our methods can also address multivariate analyses and be easily coupled with existing estimation tools. We validated the performance of these methods using simulations of common scenarios for vaccine efficacy and were able to obtain unbiased estimates in a variety of parameter settings

    Real-time dynamic modelling for the design of a cluster-randomized phase 3 Ebola vaccine trial in Sierra Leone.

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    BACKGROUND: Declining incidence and spatial heterogeneity complicated the design of phase 3 Ebola vaccine trials during the tail of the 2013-16 Ebola virus disease (EVD) epidemic in West Africa. Mathematical models can provide forecasts of expected incidence through time and can account for both vaccine efficacy in participants and effectiveness in populations. Determining expected disease incidence was critical to calculating power and determining trial sample size. METHODS: In real-time, we fitted, forecasted, and simulated a proposed phase 3 cluster-randomized vaccine trial for a prime-boost EVD vaccine in three candidate regions in Sierra Leone. The aim was to forecast trial feasibility in these areas through time and guide study design planning. RESULTS: EVD incidence was highly variable during the epidemic, especially in the declining phase. Delays in trial start date were expected to greatly reduce the ability to discern an effect, particularly as a trial with an effective vaccine would cause the epidemic to go extinct more quickly in the vaccine arm. Real-time updates of the model allowed decision-makers to determine how trial feasibility changed with time. CONCLUSIONS: This analysis was useful for vaccine trial planning because we simulated effectiveness as well as efficacy, which is possible with a dynamic transmission model. It contributed to decisions on choice of trial location and feasibility of the trial. Transmission models should be utilised as early as possible in the design process to provide mechanistic estimates of expected incidence, with which decisions about sample size, location, timing, and feasibility can be determined

    Editorial: Extreme Events in the Developing World

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    This Research Topic β€œExtreme Events in the Developing World” showcases a selection of articles that develop our knowledge of extreme events in the developing world. Papers range from those presenting recent evidence for and future likelihood of changes in the occurrence and exposure to extreme events, together with examples of the impacts of extreme events in a variety of sectors. Papers also consider the range of climate services responses to this challenge, highlighting the need for new types of weather and climate information, new methods of producing and communicating that information in order to reduce risk, as well as providing some key examples of success stories, with a particular focus on Africa. Our intention here is to balance some of the bad news with what might work, and how we might learn from such examples.UK Natural Environment Research Council (NERC); UK Government’s Department for International Development (DFID); UKRI Global Challenges Research Fund Africa-SWIFT project; NASA GPM project.https://www.frontiersin.org/journals/climatedm2022Geography, Geoinformatics and Meteorolog

    Joint localization of pursuit quadcopters and target using monocular cues

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    Pursuit robots (autonomous robots tasked with tracking and pursuing a moving target) require accurate tracking of the target's position over time. One possibly effective pursuit platform is a quadcopter equipped with basic sensors and a monocular camera. However, combined noise of the quadcopter's sensors causes large disturbances of target's 3D position estimate. To solve this problem, in this paper, we propose a novel method for joint localization of a quadcopter pursuer with a monocular camera and an arbitrary target. Our method localizes both the pursuer and target with respect to a common reference frame. The joint localization method fuses the quadcopter's kinematics and the target's dynamics in a joint state space model. We show that predicting and correcting pursuer and target trajectories simultaneously produces better results than standard approaches to estimating relative target trajectories in a 3D coordinate system. Our method also comprises a computationally efficient visual tracking method capable of redetecting a temporarily lost target. The efficiency of the proposed method is demonstrated by a series of experiments with a real quadcopter pursuing a human. The results show that the visual tracker can deal effectively with target occlusions and that joint localization outperforms standard localization methods

    Dynamics of multi-stage infections on networks

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    This paper investigates the dynamics of infectious diseases with a nonexponentially distributed infectious period. This is achieved by considering a multistage infection model on networks. Using pairwise approximation with a standard closure, a number of important characteristics of disease dynamics are derived analytically, including the final size of an epidemic and a threshold for epidemic outbreaks, and it is shown how these quantities depend on disease characteristics, as well as the number of disease stages. Stochastic simulations of dynamics on networks are performed and compared to output of pairwise models for several realistic examples of infectious diseases to illustrate the role played by the number of stages in the disease dynamics. These results show that a higher number of disease stages results in faster epidemic outbreaks with a higher peak prevalence and a larger final size of the epidemic. The agreement between the pairwise and simulation models is excellent in the cases we consider

    After the sunset: the residual effect of temporary legislation

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    The difference between permanent legislation and temporary legislation is the default rule of termination: permanent legislation governs perpetually, while temporary legislation governs for a limited time. Recent literature on legislative timing rules considers the effect of temporary legislation to stop at the moment of expiration. When the law expires, so does its regulatory effect. This article extends that literature by examining the effect of temporary legislation beyond its expiration. We show that in addition to affecting compliance behavior which depends on statutory enforcement, temporary legislation also affects compliance behavior which does not depend on statutory enforcement, and more generally, organizational behavior after a sunset. When temporary legislation expires therefore, it can continue to administer regulatory and other effects. We specify the conditions for this process and give the optimal legislative response

    An assessment of mental health policy in Ghana, South Africa, Uganda and Zambia

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    <p>Abstract</p> <p>Background</p> <p>Approximately half of the countries in the African Region had a mental health policy by 2005, but little is known about quality of mental health policies in Africa and globally. This paper reports the results of an assessment of the mental health policies of Ghana, South Africa, Uganda and Zambia.</p> <p>Methods</p> <p>The WHO Mental Health Policy Checklist was used to evaluate the most current mental health policy in each country. Assessments were completed and reviewed by a specially constituted national committee as well as an independent WHO team. Results of each country evaluation were discussed until consensus was reached.</p> <p>Results</p> <p>All four policies received a high level mandate. Each policy addressed community-based services, the integration of mental health into general health care, promotion of mental health and rehabilitation. Prevention was addressed in the South African and Ugandan policies only. Use of evidence for policy development varied considerably. Consultations were mainly held with the mental health sector. Only the Zambian policy presented a clear vision, while three of four countries spelt out values and principles, the need to establish a coordinating body for mental health, and to protect the human rights of people with mental health problems. None included all the basic elements of a policy, nor specified sources and levels of funding for implementation. Deinstitutionalisation and the provision of essential psychotropic medicines were insufficiently addressed. Advocacy, empowerment of users and families and intersectoral collaboration were inadequately addressed. Only Uganda sufficiently outlined a mental health information system, research and evaluation, while only Ghana comprehensively addressed human resources and training requirements. No country had an accompanying strategic mental health plan to allow the development and implementation of concrete strategies and activities.</p> <p>Conclusions</p> <p>Six gaps which could impact on the policies' effect on countries' mental health systems were: lack of internal consistency of structure and content of policies, superficiality of key international concepts, lack of evidence on which to base policy directions, inadequate political support, poor integration of mental health policies within the overall national policy and legislative framework, and lack of financial specificity. Three strategies to address these concerns emerged, namely strengthening capacity of key stakeholders in public (mental) health and policy development, creation of a culture of inclusive and dynamic policy development, and coordinated action to optimize use of available resources.</p
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