510 research outputs found

    Neighborhood and Individual Level Socioeconomic Variation in Perceptions of Racial Discrimination

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    In approaching the study of racial discrimination and health, the neighborhood and individual-level antecedents of perceived discrimination need further exploration. We investigated the relationship between neighborhood and individual-level socioeconomic position (SEP), neighborhood racial composition, and perceived racial discrimination in a cohort of African-American and White women age 40-79 from Connecticut, USA. Design. The logistic regression analysis included 1249 women (39% African- American and 61% White). Neighborhood-level SEP and racial composition were determined using 1990 census tract information. Individual-level SEP indicators included income, education, and occupation. Perceived racial discrimination was measured as lifetime experience in seven situations. Results. For African-American women, living in the most disadvantaged neighborhoods was associated with fewer reports of racial discrimination (odds ratio (OR) 0.44; 95% confidence interval (CI) 0.26, 0.75), with results attenuated after adjustment for individual-level SEP (OR 0.54, CI: 0.29, 1.03), and additional adjustment for neighborhood racial composition (OR 0.70, CI: 0.30, 1.63). African-American women with 12 years of education or less were less likely to report racial discrimination, compared with women with more than 12 years of education (OR 0.57, CI: 0.33, 0.98 (12 years); OR 0.51, CI: 0.26, 0.99 (less than 12 years)) in the fully adjusted model. For White women, neither neighborhood-level SEP nor individual-level SEP was associated with perceived racial discrimination. Conclusion. Individual and neighborhood-level SEP may be important in understanding how racial discrimination is perceived, reported, processed, and how it may influence health. In order to fully assess the role of racism in future studies, inclusion of additional dimensions of discrimination may be warranted

    Determination of rolling element bearing condition via acoustic emission

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    Acoustic emission is an emerging technique for condition monitoring of rolling element bearings and potentially offers advantages for detection of incipient damage at an early stage of failure. Before such a technique can be applied with confidence for health monitoring, it is vital to understand the variation of acoustic emission generation with operating conditions in a healthy bearing. This paper investigates the effects of increased speed and load on the generation of acoustic emission within cylindrical roller bearings, and it was found that the root mean square signal level increased significantly with increasing speed whereas increasing load had a far weaker effect. The AERMS value for each experiment was compared with the trend of the Lambda value. The bearing was operating under full film lubrication regime, so it was determined that increases in AERMS were not caused by asperity contact. By consideration of trends in frequency energy amplitude, it was determined that excitation of the bearings resonant frequencies were responsible for an increase of energy in the frequency range of 20–60 kHz. The excitation energy at 330 kHz (the acoustic emission sensor’s resonant frequency) increased with load, indicating a link between high-frequency emission and stress at the contact zone. Following characterisation of the bearing under normal operating conditions, an accelerated life test was conducted in order to induce fatigue failure. The frequency response demonstrated that throughout a period of constant wear, the energy amplitude at the bearings resonant frequency increased with time. As the bearing failure became more significant, the energy of the high-frequency components above 100 kHz was spread over a broader frequency range as multiple transient bursts of energy were released simultaneously by fatigue failure of the raceways. This paper demonstrates the potential of acoustic emission to provide an insight into the bearing’s behaviour under normal operation and provide early indication of bearing failure

    A Heuristic Solution of the Identifiability Problem of the Age-Period-Cohort Analysis of Cancer Occurrence: Lung Cancer Example

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    Background: The Age–Period–Cohort (APC) analysis is aimed at estimating the following effects on disease incidence: (i) the age of the subject at the time of disease diagnosis; (ii) the time period, when the disease occurred; and (iii) the date of birth of the subject. These effects can help in evaluating the biological events leading to the disease, in estimating the influence of distinct risk factors on disease occurrence, and in the development of new strategies for disease prevention and treatment. Methodology/Principal Findings: We developed a novel approach for estimating the APC effects on disease incidence rates in the frame of the Log-Linear Age-Period-Cohort (LLAPC) model. Since the APC effects are linearly interdependent and cannot be uniquely estimated, solving this identifiability problem requires setting four redundant parameters within a set of unknown parameters. By setting three parameters (one of the time-period and the birth-cohort effects and the corresponding age effect) to zero, we reduced this problem to the problem of determining one redundant parameter and, used as such, the effect of the time-period adjacent to the anchored time period. By varying this identification parameter, a family of estimates of the APC effects can be obtained. Using a heuristic assumption that the differences between the adjacent birth-cohort effects are small, we developed a numerical method for determining the optimal value of the identification parameter, by which a unique set of all APC effects is determined and the identifiability problem is solved

    Students as ecologists: Strategies for successful mentorship of undergraduate researchers

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    Guiding undergraduates through the ecological research process can be incredibly rewarding and present opportunities to break down barriers to inclusion and diversity in scientific disciplines. At the same time, mentoring undergraduate researchers is a complicated process that requires time and flexibility. While many academics receive extensive guidance on how to be successful in research endeavors, we pay much less attention to training in mentorship and working collaboratively with undergraduate students. This paper seeks to provide a framework for successfully collaborating with undergraduates including initial recruitment, development of a contract, fostering student ownership of research projects, and submission of a polished manuscript.While institutions worldwide encourage undergraduate research and publication, little training and professional development are provided to potential mentors. Our paper fills a critical gap in knowledge and provides a framework for academic mentors of all career stages to successfully guide students from question to publication.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149365/1/ece35090_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149365/2/ece35090.pd

    Population pharmacokinetics of the humanised monoclonal antibody, HuHMFG1 (AS1402), derived from a phase I study on breast cancer

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    International audienceBACKGROUND: HuHMFG1 (AS1402) is a humanised monoclonal antibody that has undergone a phase I trial in metastatic breast cancer. The aim of this study was to characterise the pharmacokinetics (PKs) of HuHMFG1 using a population PK model. METHOD: Data were derived from a phase I study of 26 patients receiving HuHMFG1 at doses ranging from 1 to 16 mg kg(-1). Data were analysed using NONMEM software and covariates were included. A limited sampling strategy (LSS) was developed using training and a validation data set. RESULTS: A linear two-compartment model was shown to be adequate to describe data. Covariate analysis indicated that weight was not related to clearance. An LSS was successfully developed on the basis of the model, in which one sample is collected immediately before the start of an infusion and the second is taken at the end of infusion. CONCLUSION: A two-compartment population PK model successfully describes HuHMFG1 behaviour. The model suggests using a fixed dose of HuHMFG1, which would simplify dosing. The model could be used to optimise dose level and dosing schedule if more data on the correlation between exposure and efficacy become available from future studies. The derived LSS could optimise further PK assessment of this antibody

    The misuses of sustainability: adult education, citizenship and the dead hand of neoliberalism

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    ‘‘Sustainability’’ has a captivating but disingenuous simplicity: its meanings are complex, and have political and policy significance. Exploring the application of the term to adult education, this paper argues that a particular discourse of ‘‘sustainability’’ has become a common-sense, short-circuiting critical analysis and understanding of policy options. This ‘‘business discourse’’ of sustainability, strongly influenced by neoliberal ideas, encourages the presumption that educational programmes and movements which have died out were unsustainable, bound to fail, and even responsible – having failed to adapt – for their own demise. Potentially valuable experience is thus excluded from the educational policy canon. The author uses three cases from 20th-century adult education, namely (1) English liberal adult education; (2) ‘‘mass education’’, also known as community development, in the British colonies; and (3) UNESCO’s Fundamental Education, to challenge this presumption. He demonstrates for each case how a business discourse has implied their ‘‘unsustainability’’, but that the reality was more complex and involved external political intervention

    Play and the exhibition:the problematic fun of showcasing of videogames in informal and formal contexts

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    Video games are inherently problematic as cultural artefacts, presenting issues of stability, currency, interaction and participation (to name but a few) in their curation. These issues are not necessarily unique to video games in an exhibition context, but their combination with the on-going debate about the status of video games as an art form inspire discussion and debate. Despite the issues presented by video games, there have been countless video game exhibitions in formal and informal contexts, typically focussing upon the historical narrative around games or their position as artefacts with cultural value. It is only in the last few years that artistic and academic study of this problematic field has developed traction, through both an emerging body of literature looking to formalise video games exhibitions practices and practitioner debate. 2019 sees the inaugural Game Arts International Assembly “a think tank for the international games arts ecosystem” bringing together leading curators and makers working at the forefront of public display of interactive arts and playful media.This paper contributes to the developing body of knowledge which analyses video games exhibition methods by formalising and evaluating the methods utilised within informal and formal contexts of video games exhibition from the perspective of reception theory. The study of both large scale exhibition such as those orchestrated by the Victoria and Albert museum and the Smithsonian American Art Museum alongside the one night indie game night or play party is a unique contribution to the field, with studies typically focussing on approaches within one given context. Reception theory provides a lens through which the active participative role of the attendee or visitor in meaning making can be evaluated and allows consideration of the connection between selected methods of exhibition and the resulting meaning making opportunities possible for a range of potential audiences
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