812 resultados para Critical Race Studies
Resumo:
As a consequence of increased levels of flooding, largely attributable to urbanization of watersheds (and perhaps climate change, more frequent extreme rainfall events are occurring and threatening existing critical infrastructure. Many of which are short-span bridges over relatively small waterways (e.g., small rivers, streams and canals). Whilst these short-span bridges were designed, often many years ago, to pass relatively minor the then standard return-period floods, in recenttimes the failure incidence of such short-span bridges has been noticeably increasing. This is suggestive of insufficient hydraulic capacity or alternative failure mechanism not envisaged at the time of design e.g. foundation scour or undermining. This paper presen ts, and draws lessons, from bridge failures in Ireland and the USA. For example, in November 2009, the UK and Ireland were subjected to extraordinarily severe weather conditions for several days. The resulting flooding led to the collapse of three UK bridges that were generally 19th century masonry arch bridges, withrelatively shallow foundations. Parallel failure events have been observed in the USA. To date, knowledge of the combined effect of waterway erosion, bridge submergence, and geotechnical collapse has not been adequately studied. Recent research carried out considered the hydraulic analysis of short span bridges under flood conditions, but no consideration was given towards the likely damage to these structures due to erosive coupling of hydraulic and geotechnical factors. Some work has been done to predict the discharge downstream of an inundated arch, focusing onpredicting afflux, as opposed to bridge scour, under both pressurized and free-surface flows, but no ! predictive equation for scour under pressurized conditions was ever considered. The case studies this paper presents will be augmented by the initial findings from the laboratory experiments investigating the effects of surcharged flow and subsequent scour within the vicinity of single span arch bridges. Velocities profiles will be shown within the vicinity of the arch, in addition to the depth of consequent scour, for a series of flows and model spans. The data will be presented and correlated to the most recent predictive equations for submerged contraction and abutment scour. The accuracy of these equations is examined, and the findings used as a basis for developing further studies in relation to short span bridges.
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A new experimental technique for femtosecond (fs) pulse studies of gas phase biomolecules is reported. Using Laser-Induced Acoustic Desorption (LIAD) to produce a plume of neutral molecules, a time-delayed fs pulse is employed for ionisation/fragmentation, with subsequent products extracted and mass analysed electrostatically. By varying critical laser pulse parameters, this technique can be used to implement control over molecular fragmentation for a range of small biomolecules, with specific studies of amino acids demonstrated.
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Twentieth century public health initiatives have been crucially informed by perceptions and constructions of risk. Notions of risk identification, assessment and mitigation have guided political and institutional actions even before these concepts became an explicit part of the language of public administration and policy making. Past analyses investigating the link between risk perceptions and public health are relatively rare, and where researchers have investigated this nexus, it has typically been assumed that the collective identification of health risks has led to progressive improvements in public health activities.
Risk and the Politics of Public Health addresses this gap by presenting a detailed critical historical analysis of the evolution of risk thinking within medical and health related discourses. Grouped around the four core themes of 'immigration', 'race', 'armed conflict' and 'detention and prevention' this book highlights the innovative capacity of risk related concepts as well as their vulnerability to the dysfunctional effects of dominant social ideologies. Risk and the Politics of Public Health is an essential reference for those who seek to understand the interplay of concepts of risk and public health throughout history as well as those who wish to gain a critical understanding of the social dynamics which have underpinned, and continue to underpin, this complex interaction.
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PURPOSE:
To determine the accuracy of a history of cataract and cataract surgery (self-report and for a sibling), and to determine which demographic, cognitive, and medical factors are predictive of an accurate history.
METHODS:
All participants in the Salisbury Eye Evaluation (SEE) project and their locally resident siblings were questioned about a personal and family history of cataract or cataract surgery. Lens grading at the slit lamp, using standardized photographs and a grading system, was performed for both SEE participants (probands) and their siblings. Cognitive testing and a history of systemic comorbidities were also obtained for all probands.
RESULTS:
Sensitivity of a history of cataract provided on behalf of a sibling was 32%, specificity 98%. The performance was better for a history of cataract surgery: sensitivity 90%, specificity 89%. For self-report of cataract, sensitivity was also low at 55%, with specificity at 77%. Self-report of cataract surgery gave a much better performance: sensitivity 94%, specificity 100%. Different cutoffs in the definition of cataract had little impact. Factors predicting a correct history of cataract included high school or greater education in the proband (odds ratio [OR] = 1.13, 95% confidence interval [CI]1.02-1.25) and younger sibling (but not proband) age (OR = 0.94 for each year of age, 95% CI 0.90-0.99). Gender, race and Mini-Mental Status Examination (MMSE) result were not predictive.
CONCLUSIONS:
Whereas accurate self and family histories for cataract surgery may be obtainable, it is difficult to ascertain cataract status accurately from history alone.
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This dissertation examines the emergence and development of sound installation art, an under-recognized tradition that has developed between music, architecture, and media art practices since the late 1950s. Unlike many musical works, which are concerned with organizing sounds in time, sound installations organize sounds in space; they thus necessitate new theoretical and analytical models that take into consideration the spatial situated-ness of sound. Existing discourses on “spatial sound” privilege technical descriptions of sound localization. By contrast, this dissertation examines the ways in which concepts of space are socially, culturally, and politically construed, and how spatially-organized sound works reflect and resist these different constructions. Using an interdisciplinary methodology of critical spatial analysis and critical studies in music, this dissertation explores such topics as: conceptions of acoustic space in postwar Western art music, architecture, and media theory; the development of sound installation art in relation to philosophies of everyday life and social space; the historical links between musical performance, conceptual art, and sound sculpture; the body as a site for sound installations; and sonicspatial strategies that confront politics of race and gender. Through these different investigations, this dissertation proposes an “ontopological” model for considering sound: a critical model of analysis and reception that privileges an understanding of sound in relation to ontologies of space and place.
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Procedural pain in neonates has been a concern in the last two decades. The purpose of this review was to provide a critical appraisal and a synthesis of the published epidemiological studies about procedural pain in neonates admitted to intensive care units. The aims were to determine the frequency of painful procedures and pain management interventions as well as to identify their predictors. Academic Search, CINAHL, LILACS, Medic Latina, MEDLINE and SciELO databases were searched for observational studies on procedural pain in neonates admitted to intensive care units. Studies in which neonatal data could not be extracted from the paediatric population were excluded. Eighteen studies were included in the review. Six studies with the same study duration, the first 14 days of the neonate life or admission in the unit of care, identified 6832 to 42,413 invasive procedures, with an average of 7.5-17.3 per neonate per day. The most frequent procedures were heel lance, suctioning, venepuncture and insertion of peripheral venous catheter. Pharmacological and nonpharmacological approaches were inconsistently applied. Predictors of the frequency of procedures and analgesic use included the neonate's clinical condition, day of unit stay, type of procedure, parental presence and pain assessment. The existence of pain protocols was not a predictor of analgesia. Painful procedures were performed frequently and often with inadequate pain management. Unlike neonate clinical factors, organizational factors may be modified to promote a context of care more favourable to pain management. © 2015 European Pain Federation - EFIC®
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The work presented in this Ph.D thesis was developed in the context of complex network theory, from a statistical physics standpoint. We examine two distinct problems in this research field, taking a special interest in their respective critical properties. In both cases, the emergence of criticality is driven by a local optimization dynamics. Firstly, a recently introduced class of percolation problems that attracted a significant amount of attention from the scientific community, and was quickly followed up by an abundance of other works. Percolation transitions were believed to be continuous, until, recently, an 'explosive' percolation problem was reported to undergo a discontinuous transition, in [93]. The system's evolution is driven by a metropolis-like algorithm, apparently producing a discontinuous jump on the giant component's size at the percolation threshold. This finding was subsequently supported by number of other experimental studies [96, 97, 98, 99, 100, 101]. However, in [1] we have proved that the explosive percolation transition is actually continuous. The discontinuity which was observed in the evolution of the giant component's relative size is explained by the unusual smallness of the corresponding critical exponent, combined with the finiteness of the systems considered in experiments. Therefore, the size of the jump vanishes as the system's size goes to infinity. Additionally, we provide the complete theoretical description of the critical properties for a generalized version of the explosive percolation model [2], as well as a method [3] for a precise calculation of percolation's critical properties from numerical data (useful when exact results are not available). Secondly, we study a network flow optimization model, where the dynamics consists of consecutive mergings and splittings of currents flowing in the network. The current conservation constraint does not impose any particular criterion for the split of current among channels outgoing nodes, allowing us to introduce an asymmetrical rule, observed in several real systems. We solved analytically the dynamic equations describing this model in the high and low current regimes. The solutions found are compared with numerical results, for the two regimes, showing an excellent agreement. Surprisingly, in the low current regime, this model exhibits some features usually associated with continuous phase transitions.
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: In this paper, I look at Joanne Leonard’s Being in Pictures and engage in a critical dialogue with an assemblage of visual and textual narratives that comprise her intimate photo memoir. In doing this I draw on Hannah Arendt’s take on narratives as tangible traces of uniqueness and plurality, political traits par excellence in the cultural histories of the human condition. Being aware of my role as a reader/viewer/interpreter of a woman artist’s auto/biographical narratives, I move beyond dilemmas of representation or questions of unveiling “the real Leonard”. The artist is instead configured as a narrative persona, whose narratives respond to three interrelated themes of inquiry, namely the visualization of spatial technologies, vulnerability and the gendering of memory. Key words: gendered memories, narrative persona, spatial technologies, photo memoir, vulnerability
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Tese de doutoramento, Biologia (Biologia Marinha e Aquacultura), Universidade de Lisboa, Faculdade de Ciências, 2015
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Thesis (Ph.D.)--University of Washington, 2013
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This paper discusses the literature on the established determinants of productivity in the retail sector. It also draws attention to some neglected strands of research which provide useful insights into strategies that could allow productivity enhancements in this area of the economy. To date, very few attempts have been made to integrate different specialisms in order to explain what drives productivity in retail. Here this paper rectifies this omission by putting together studies from economics, geography, knowledge management and employment studies. It is the authors' view that quantitative studies of retail productivity should focus on total factor productivity in retailing as the result of competition/composition effects, planning regulations, information and communications technology, the multinational operation element and workforce skills. Further, the fact that retail firms possess advantages that are transferable between locations suggests that investment in strategies enhancing the transfer of explicit and tacit knowledge between and within businesses are crucial to achieve productivity gains.
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This thesis explores the processes through which scarcity is constructed in informal settlements and how conditions emerging within its limits gives way to particular socio-spatial phenomena and influence the emergence of self-organisation and creative strategies from a non-expert perspective. At the same time, this thesis deconstructs these emerging tactics (reactive and transformative) in a diagrammatic way to generate a critical study of their potential for socio-spatial change that goes beyond the everyday survival. Most people associate scarcity with “not having enough” of something, most usually of a material nature. In contrast, this paper is based on the premise that scarcity is a constructed condition, therefore exploring it beyond its immediate manifestation and illustrating its discursive, distributive and socio-material components. In this line, the research uses Assemblage Theory as both an approach and a tool for analysis. This approach allows the research to depart from everyday narratives of the residents, and gradually evolve into a multi-scalar, non-linear reading of scarcity, by following leads into different realms and unpacking a series of routine events to uncover their connections to wider processes and particular elements affecting the settlement and the city as a whole. For this purpose, the research is based on a qualitative, flexible and multi-sited methodology, using different case studies as testing grounds. Collected data stems from a 11-months ethnographic fieldwork in informal settlements in Ecuador and Kenya, analysing the socio-spatial practices and strategies deployed by the different actors producing the built environment and arising from everyday and latent experiences of scarcity. The thesis examines the multi-scalar nature of these strategies, including self-building and management tactics, the mobilisation of grassroots organisations, the innovative ways of collaborating deployed by different coalitions and the reformulation of urban development policies. As outcomes of the research, the thesis will show illustrative diagrams that allow a better understanding of, firstly, the construction of scarcity in the built environment beyond its immediate manifestation and secondly, the way that emerging tactics a) improve existing conditions of scarcity, b) reinforce the status quo or c) contribute to the worsening of the original condition. Therefore, this thesis aims to offer lessons with both practical and theoretical considerations, by firstly, giving an insight into the complexity and transcalar nature of the construction of scarcity in informal settlements; secondly, by illustrating how acute conditions related to scarcity gives birth to a plethora of particular phenomena shaping the territory, social relationships and processes; and thirdly, by identifying specific characteristics within the informal that might allow for new readings of the city and possibilities for socio-spatial change under conditions of scarcity.
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The key argument set out in this article is that historical and comparative forms of investigation are necessary if we are to better understand the ambitions and scope of contemporary housing interventions. To demonstrate the veracity of our claim we have set out an analysis of UK housing polices enacted in the mid 1970s as a basis for comparison with those pursued forty years later. The article begins with a critical summary of some of the methodological approaches adopted by researchers used to interpret housing policy. In the main section we present our critical analysis of housing policy reforms (implemented by the Labour government between 1974 and 1979) noting both their achievements and limitations. In the concluding section, we use our interpretation of this period as a basis to judge contemporary housing policy and reflect on the methodological issues that arise from our analysis.