1,664 research outputs found
Quantitative Assessment of Deformation-Induced Damage in a Semisolid Aluminum Alloy via X-ray Microtomography
Semisolid tensile testing combined with X-ray microtomography (XMT) was used to characterize the development of internal damage as a function of strain in an aluminum-magnesium alloy, AA5182. Novel techniques were developed to allow the quantification of both the size evolution and orientation of the damage to determine mechanisms controlling the early stage growth and localization. During the initial stages of semisolid deformation, it was observed that strain was accommodated by both the growth of as-cast porosity and the detection of new damage-based voids. As the volume fraction of damage increases, the growth of voids occurs in an orientation perpendicular to the loading direction, both through expansion within the grain boundary liquid and void coalescence. The damage then localizes, causing failur
Perturbation of the Classic Binary Adduct C6H6:C6F6 by Chlorine Substitution
This paper presents a comprehensive exploration of the impact of
monochlorine substitution on the solid-state phases of the classic binary adduct
C6H6:C6F6. Crystal structures for all four phases of C6H6:C6F5Cl were determined
using single-crystal X-ray diffraction, with complementary data from differential
scanning calorimetry (DSC) and variable-temperature powder X-ray diffraction
(VT-PXRD). The study reveals that phases I and III would have been overlooked
without the additional information provided by DSC and PXRD. Symmetry changes
during the phase transitions, including the loss of 3-fold and mirror symmetry, are
crucial for our understanding of the observed transformations. Comparisons with
the prototype C6H6:C6F6, the methyl-substituted C6H5CH3:C6F6 and iodine-substituted analogue C6H6:(C6F5I)2 provide useful
insights into the noncovalent interactions holding these cocrystals together. The experimental results herein may be useful for
informing crystal structure prediction, especially in distinguishing between structures of similar energy
Knowledge Wars: Professionalisation, Organisational Justice and Competing Knowledge Paradigms in British Policing
The professionalisation agenda in British policing is being driven by the College of Policing.
Whilst there are a number of definitions of professionalism (Sklansky, 2014), the basic tenets
of a professional organisation are that the employees follow a code of ethics, there is a
commitment to use expert knowledge and that there is an element of self-regulation. Within
the professionalisation agenda for the British police there are a number of strands. These
include the implementation of a police code of ethics, the development of a police education
qualification framework (PEQF) and wide support of police and academic collaborations to
ensure police practice becomes increasingly evidence based. This chapter focuses on the latter
strand of work, evidence based policing (EBP), particularly as there has been extensive debate
in both the academic and policing fields about the extent to which police officers are both
supportive and understanding of this concept and the extent to which they feel involved in EBP
at all stages of the process (Fleming and Wingrove, 2017). In doing so, the chapter will seek to
explore some of the potential issues which arise in respect of EBP by using the theory and
principles of organisational justice. This will be used to explore the changing conceptualisation
of knowledge within police organisations and the link this has with the professionalisation of
policing. We will attempt to do this firstly, by exploring the concept and principles of
organisational justice and applying this to the context of policing, EBP and knowledge work.
Secondly, we will explore what we mean by knowledge in a police context and, thirdly, we
will examine the potential to apply the concept of organisational justice to current views on the
constitution of knowledge and knowledge outputs in the modern policing milie
Assessment of resource availability and sustainability for subsistence fishers in South Africa, with a review of resource management procedures
The availability of resources and their suitability for subsistence and small-scale commercial fishers in South Africa were assessed and appropriate options for the management of resources recommended. Assessment of current resource utilization and recommendations for future subsistence and/or small-scale commercial use were based on information gathered during a nationwide survey of 144 subsistence fishing communities in South Africa and a review of relevant published and unpublished literature. Current patterns of resource use in three regions of the coast (West, South and East coasts) revealed that most true subsistence fisheries occur in the eastern half of the country. These fisheries are primarily focused on invertebrate species found on intertidal rocky shores and sandy beaches, or in estuaries. Fish are harvested by rod or handline, netting or traditional fishing methods (fishtraps, spearing, baited baskets). No “new” or previously underutilized resources were identified as suitable for subsistence fishing in any of the three regions. The potential for several new small-scale commercial fisheries was identified, but the need to retain certain resources for subsistence fisheries (rather than converting them to small-scale commercial fisheries) was evident in certain areas. Resources with high commercial value were not considered suitable for subsistence fishing, but rather for the introduction of small-scale commercial fisheries. The overall management strategy for the subsistence sector, which is currently in the process of being developed, must ensure sufficient flexibility to be able to take into account regional and site-specific requirements. It will also need to develop co-management structures, protect traditional fishing practices, avoid user conflict and provide for no-take areas, all within the framework of sustainable resource utilization.Keywords: estuarine resources, fisheries management, intertidal resources, subsistence fisheries, subtidal resourcesAfrican Journal of Marine Science 2002, 24: 489–50
Role of Leukotriene Receptor Antagonists in the Treatment of Exercise-Induced Bronchoconstriction: A Review
Asthma is a very common disorder that still causes significant morbidity and mortality. A high percentage of individuals with asthma also experience exercise-induced bronchoconstriction (EIB). This article reviews the current literature and updates the reader on the safety, efficacy, and clinical applications of leukotriene modifiers in the treatment of EIB
Revisiting the need for a literature search narrative: A brief methodological note
This is the author accepted manuscript. The final version is available from Wiley via the DOI inthis recordIn this method note, we question if the primary search strategy in a systematic review should be accompanied by a search narrative. A search narrative could offer a conceptual and contextual report on the search strategy, which we suggest might benefit the peer review of literature searches and increase engagement with, and discussion of, the literature search strategy from review stakeholders, topic experts, and lay users of research. Search narratives would also increase the transparency of decision-making in literature searching.Centre for Outcomes Research and Effectiveness (CORE)National Institute for Health Research (NIHR)Cochrane Common Mental Disorders (CCMD) Grou
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Vitamin D intake and risk of CVD and all-cause mortality: evidence from the Caerphilly Prospective Cohort Study
OBJECTIVE:
Prospective data on the associations between vitamin D intake and risk of CVD and all-cause mortality are limited and inconclusive. The aim of the present study was to investigate the associations between vitamin D intake and CVD risk and all-cause mortality in the Caerphilly Prospective Cohort Study.
DESIGN:
The associations of vitamin D intake with CVD risk markers were examined cross-sectionally at baseline and longitudinally at 5-year, 10-year and >20-year follow-ups. In addition, the predictive value of vitamin D intake for CVD events and all-cause mortality after >20 years of follow-up was examined. Logistic regression and general linear regression were used for data analysis.
SETTING:
Participants in the UK.
SUBJECTS:
Men (n 452) who were free from CVD and type 2 diabetes at recruitment.
RESULTS:
Higher vitamin D intake was associated with increased HDL cholesterol (P=0·003) and pulse pressure (P=0·04) and decreased total cholesterol:HDL cholesterol (P=0·008) cross-sectionally at baseline, but the associations were lost during follow-up. Furthermore, higher vitamin D intake was associated with decreased concentration of plasma TAG at baseline (P=0·01) and at the 5-year (P=0·01), but not the 10-year examination. After >20 years of follow-up, vitamin D was not associated with stroke (n 72), myocardial infarctions (n 142), heart failure (n 43) or all-cause mortality (n 281), but was positively associated with increased diastolic blood pressure (P=0·03).
CONCLUSIONS:
The study supports associations of higher vitamin D intake with lower fasting plasma TAG and higher diastolic blood pressure
Does pulmonary rehabilitation address cardiovascular risk factors in patients with COPD?
Background Patients with COPD have an increased risk of cardiovascular disease. Whilst pulmonary rehabilitation has proven benefit for exercise tolerance and quality of life, any effect on cardiovascular risk has not been fully investigated. We hypothesised that pulmonary rehabilitation, through the exercise and nutritional intervention, would address these factors. Methods Thirty-two stable patients with COPD commenced rehabilitation, and were compared with 20 age and gender matched controls at baseline assessment. In all subjects, aortic pulse wave velocity (PWV) an independent non-invasive predictor of cardiovascular risk, blood pressure (BP), interleukin-6 (IL-6) and fasting glucose and lipids were determined. These measures, and the incremental shuttle walk test (ISWT) were repeated in the patients who completed pulmonary rehabilitation. Results On commencement of rehabilitation aortic PWV was increased in patients compared with controls (p < 0.05), despite mean BP, age and gender being similar. The IL-6 was also increased (p < 0.05). Twenty-two patients completed study assessments. In these subjects, rehabilitation reduced mean (SD) aortic PWV (9.8 (3.0) to 9.3 (2.7) m/s (p < 0.05)), and systolic and diastolic BP by 10 mmHg and 5 mmHg respectively (p < 0.01). Total cholesterol and ISWT also improved (p < 0.05). On linear regression analysis, the reduction in aortic PWV was attributed to reducing the BP. Conclusion Cardiovascular risk factors including blood pressure and thereby aortic stiffness were improved following a course of standard multidisciplinary pulmonary rehabilitation in patients with COPD
The EPICure study: association between hemodynamics and lung function at 11 years after extremely preterm birth.
To investigate the relationship between disturbed lung function and large-artery hemodynamics in school-age children born extremely preterm (EP) (at 25 completed weeks of gestation or less)
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