83 research outputs found

    Upper cenozoic chronostratigraphy of the southwestern Amazon Basin

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    The lack of numerical age dates for upper Cenozoic strata of the Amazon Basin has prevented resolution of its geologic history and accurate dating of important paleofaunas. Here we present results of magnetostratigraphy and 40Ar/39Ar dating of two volcanic ash deposits from the Madre de Dios Formation of eastern Peru. The two ash ages, 9.01 ± 0.28 Ma and 3.12 ± 0.02 Ma, provide the first numerical age data necessary for accurate interpretation of late Tertiary sedimentation in Amazonia and establish approximate time constraints for the last major cycle of Cenozoic deposition within the southwestern Amazon Basin. The older ash age also provides a minimum age for numerous Amazonian paleofaunas, which allows a more definitive correlation of these paleofaunas with those in other regions of South America

    Limiting wave conditions for the safe maintenance of floating wind turbines

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    This paper investigates the limiting wave conditions at which a wind turbine technician can complete maintenance activities safely and effectively on a 15MW floating offshore wind turbine. Through linear, frequency-domain statistical analysis of floating turbine motion and applying acceptable motion limits for technician working, significant wave height and peak wave period limits are investigated. It was found that over the range of wave conditions considered, the turbine nacelle motion did not exceed the motion limits for technician working considered in this analysis. Further analysis found that the turbine nacelle motion increased with increasing significant wave height and was also significantly influenced by peak wave period. The impact of differing wave characteristics is also investigated through the use of different wave energy spectra and also found to have an impact on turbine nacelle motion

    Achieving Quality and Effectiveness in Dementia Using Crisis Teams (AQUEDUCT): a study protocol for a randomised controlled trial of a Resource Kit.

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    BACKGROUND: Improving care at home for people with dementia is a core policy goal in the dementia strategies of many European countries. A challenge to effective home support is the occurrence of crises in the care of people with dementia which arise from changes in their health and social circumstances. Improving the management of these crises may prevent hospital admissions and facilitate better and longer care at home. This trial is part of a National Institute for Health Research funded programme, AQUEDUCT, which aims to improve the quality and effectiveness of teams working to manage crises in dementia. METHODS/DESIGN: It is a pragmatic randomised controlled trial of an online Resource Kit to enhance practice in teams managing crises in dementia care. Thirty teams managing mental health crises in dementia in community settings will be randomised between the Resource Kit intervention and treatment as usual. The primary outcome measure is psychiatric admissions to hospital for people with dementia in the teams' catchment area recorded 6 months after randomisation. Other outcomes include quality of life measures for people with dementia and their carers, practitioner impact measures, acute hospital admissions and costs. To enhance understanding of the Resource Kit intervention, qualitative work will explore staff, patient and carers' experience. DISCUSSION: The Resource Kit intervention reflects current policy to enable home-based care for people with dementia by addressing the management of crises which threaten the viability of care at home. It is based upon a model of best practice for managing crises in dementia designed to enhance the quality of care, developed in partnership with people with dementia, carers and practitioners. If the Resource Kit is shown to be clinically and cost-effective in this study, this will enhance the probability of its incorporation into mainstream practice. TRIAL REGISTRATION: ISRCTN 42855694 ; Registered on 04/03/2021; Protocol number: 127686/2020v9; Research Ethics Committee, 09/03/2021, Ref 21/WM/0004; IRAS ID: 289982

    The role of religion in the longer-range future, April 6, 7, and 8, 2006

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    This repository item contains a single issue of the Pardee Conference Series, a publication series that began publishing in 2006 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future. This conference that took place during April 6, 7, and 8, 2006. Co-organized by David Fromkin, Director, Frederick S. Pardee Center for the Study of the Longer-Range Future, and Ray L. Hart, Dean ad interim Boston University School of TheologyThe conference brought together some 40 experts from various disciplines to ponder upon the “great dilemma” of how science, religion, and the human future interact. In particular, different panels looked at trends in what is happening to religion around the world, questions about how religion is impacting the current political and economic order, and how the social dynamics unleashed by science and by religion can be reconciled.Carnegie Council on Ethics and International Affair

    Anatomical Global Spatial Normalization

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    Anatomical global spatial normalization (aGSN) is presented as a method to scale high-resolution brain images to control for variability in brain size without altering the mean size of other brain structures. Two types of mean preserving scaling methods were investigated, “shape preserving” and “shape standardizing”. aGSN was tested by examining 56 brain structures from an adult brain atlas of 40 individuals (LPBA40) before and after normalization, with detailed analyses of cerebral hemispheres, all gyri collectively, cerebellum, brainstem, and left and right caudate, putamen, and hippocampus. Mean sizes of brain structures as measured by volume, distance, and area were preserved and variance reduced for both types of scale factors. An interesting finding was that scale factors derived from each of the ten brain structures were also mean preserving. However, variance was best reduced using whole brain hemispheres as the reference structure, and this reduction was related to its high average correlation with other brain structures. The fractional reduction in variance of structure volumes was directly related to ρ2, the square of the reference-to-structure correlation coefficient. The average reduction in variance in volumes by aGSN with whole brain hemispheres as the reference structure was approximately 32%. An analytical method was provided to directly convert between conventional and aGSN scale factors to support adaptation of aGSN to popular spatial normalization software packages

    Achieving Quality and Effectiveness in Dementia Using Crisis Teams (AQUEDUCT): A Study Protocol for a Randomised Controlled Trial of a Resource Kit.

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    BACKGROUNDImproving care at home for people with dementia is a core policy goal in the dementia strategies of many European countries. A challenge to effective home support is the occurrence of crises in the care of people with dementia which arise from changes in their health and social circumstances. Improving the management of these crises may prevent hospital admissions and facilitate better and longer care at home. This trial is part of a National Institute for Health Research funded programme, AQUEDUCT, which aims to improve the quality and effectiveness of teams working to manage crises in dementia.METHODS/DESIGNIt is a pragmatic randomised controlled trial of an online Resource Kit to enhance practice in teams managing crises in dementia care. Thirty teams managing mental health crises in dementia in community settings will be randomised between the Resource Kit intervention and treatment as usual. The primary outcome measure is psychiatric admissions to hospital for people with dementia in the teams’ catchment area recorded six months after randomisation. Other outcomes include: quality of life measures for people with dementia and their carers; practitioner impact measures; acute hospital admissions; and costs. To enhance understanding of the resource kit intervention, qualitative work will explore staff, patient and carers’ experience.DISCUSSIONThe Resource Kit intervention reflects current policy to enable home-based care for people with dementia by addressing the management of crises which threaten the viability of care at home. It is based upon a model of best practice for managing crises in dementia designed to enhance the quality of care, developed in partnership with people with dementia, carers and practitioners. If the Resource Kit is shown to be clinically and cost effective in this study, this will enhance the probability of its incorporation into mainstream practice.TRIAL REGISTRATION: ISRCTN 42855694; Registered on 04/03/2021; Protocol number: 127686/2020v9; Research Ethics Committee, 09/03/2021, Ref 21/WM/0004; IRAS ID: 28998

    Genetic Assignment Methods for Gaining Insight into the Management of Infectious Disease by Understanding Pathogen, Vector, and Host Movement

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    For many pathogens with environmental stages, or those carried by vectors or intermediate hosts, disease transmission is strongly influenced by pathogen, host, and vector movements across complex landscapes, and thus quantitative measures of movement rate and direction can reveal new opportunities for disease management and intervention. Genetic assignment methods are a set of powerful statistical approaches useful for establishing population membership of individuals. Recent theoretical improvements allow these techniques to be used to cost-effectively estimate the magnitude and direction of key movements in infectious disease systems, revealing important ecological and environmental features that facilitate or limit transmission. Here, we review the theory, statistical framework, and molecular markers that underlie assignment methods, and we critically examine recent applications of assignment tests in infectious disease epidemiology. Research directions that capitalize on use of the techniques are discussed, focusing on key parameters needing study for improved understanding of patterns of disease

    Estimation of coronary artery hyperemic blood flow based on arterial lumen volume using angiographic images

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    The purpose of this study is to develop a method to estimate the hyperemic blood flow in a coronary artery using the sum of the distal lumen volumes in a swine animal model. The limitations of visually assessing coronary artery disease are well known. These limitations are particularly important in intermediate coronary lesions where it is difficult to determine whether a particular lesion is the cause of ischemia. Therefore, a functional measure of stenosis severity is needed using angiographic image data. Coronary arteriography was performed in 10 swine (Yorkshire, 25–35 kg) after power injection of contrast material into the left main coronary artery. A densitometry technique was used to quantify regional flow and lumen volume in vivo after inducing hyperemia. Additionally, 3 swine hearts were casted and imaged post-mortem using cone-beam CT to obtain the lumen volume and the arterial length of corresponding coronary arteries. Using densitometry, the results showed that the stem hyperemic flow (Q) and the associated crown lumen volume (V) were related by Q = 159.08 V3/4 (r = 0.98, SEE = 10.59 ml/min). The stem hyperemic flow and the associated crown length (L) using cone-beam CT were related by Q = 2.89 L (r = 0.99, SEE = 8.72 ml/min). These results indicate that measured arterial branch lengths or lumen volumes can potentially be used to predict the expected hyperemic flow in an arterial tree. This, in conjunction with measured hyperemic flow in the presence of a stenosis, could be used to predict fractional flow reserve based entirely on angiographic data

    The use of mobile phone data for the estimation of the travel patterns and imported Plasmodium falciparum rates among Zanzibar residents

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    Background: malaria endemicity in Zanzibar has reached historically low levels, and the epidemiology of malaria transmission is in transition. To capitalize on these gains, Zanzibar has commissioned a feasibility assessment to help inform on whether to move to an elimination campaign. Declining local transmission has refocused attention on imported malaria. Recent studies have shown that anonimized mobile phone records provide a valuable data source for characterizing human movements without compromising the privacy of phone users. Such movement data in combination with spatial data on P. falciparum endemicity provide a way of characterizing the patterns of parasite carrier movements and the rates of malaria importation, which have been used as part of the malaria elimination feasibility assessment for the islands of Zanzibar. Data and methods: records encompassing three months of complete mobile phone usage for the period October-December 2008 were obtained from the Zanzibar Telecom (Zantel) mobile phone network company, the principal provider on the islands of Zanzibar. The data included the dates of all phone usage by 770,369 individual anonymous users. Each individual call and message was spatially referenced to one of six areas: Zanzibar and five mainland Tanzania regions. Information on the numbers of Zanzibar residents travelling to the mainland, locations visited and lengths of stay were extracted. Spatial and temporal data on P. falciparum transmission intensity and seasonality enabled linkage of this information to endemicity exposure and, motivated by malaria transmission models, estimates of the expected patterns of parasite importation to be made. Results: over the three month period studied, 88% of users made calls that were routed only through masts on Zanzibar, suggesting that no long distance travel was undertaken by this group. Of those who made calls routed through mainland masts the vast majority of trips were estimated to be of less than five days in length, and to the Dar Es Salaam Zantel-defined region. Though this region covered a wide range of transmission intensities, data on total infection numbers in Zanzibar combined with mathematical models enabled informed estimation of transmission exposure and imported infection numbers. These showed that the majority of trips made posed a relatively low risk for parasite importation, but risk groups visiting higher transmission regions for extended periods of time could be identified. Conclusion: anonymous mobile phone records provide valuable information on human movement patterns in areas that are typically data-sparse. Estimates of human movement patterns from Zanzibar to mainland Tanzania suggest that imported malaria risk from this group is heterogeneously distributed; a few people account for most of the risk for imported malaria. In combination with spatial data on malaria endemicity and transmission models, movement patterns derived from phone records can inform on the likely sources and rates of malaria importation. Such information is important for assessing the feasibility of malaria elimination and planning an elimination campaign
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