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Literary practices, personhood, and students as researchers of their own communities.
This dissertation reports findings from a sociolinguistic ethnography that examined relationships between literacy practices and personhood. The study involved the formulation of a writing club at an urban middle school, involving a multiracial group of women from the lowest academic track; two were described as special education students. They researched and wrote about their communities, investigating questions of personal concern about issues of racism and sexism. Students interviewed community members, including artists, organizers, neighbors, and peers. Students wrote up and published their findings. I collected data on the writing project, including forty-five hours of taped data. Analysis involved thematic and textual analyses of the students\u27 written artifacts, and microanalysis of videotaped events. A microethnographic analysis examined sociolinguistic processes that research suggested is important. Attention was paid to the social construction of intertextuality during writing activities. The findings show that the nature of literacy practices and personhood is such that they are continuously and inherently constructed within particular fields of intertextual semantic potentials. These intertextual potentials are described along five dimensions: (1) ways students\u27 definitions of personhood changed over the course of the project, (2) strategies students, community members, and myself used to position students, (3) how the project\u27s structure positioned students, (4) community literacy practices and how they positioned people, (5) how students used community literacy practices to position themselves and others. The student\u27s definitions of personhood changed. The established field of intertextual semantic potentials was influenced by changes in literacy practices that led to changes in literacy practices that led to changes in the students\u27 definitions of writing, their views about themselves and life in the community. Literacy practices established in the writing project built on ones students encountered as they researched their communities. Community members shared ways of acting for social justice, including the importance of reclaiming cultural heritage, learning history from the community\u27s perspective, analyzing multiple forms of oppression. Students\u27 ethnographic research helped them reflect on their communities by enhancing their understanding of the cultural dynamics in which they live. Students recreated methods and theoretical frameworks to address the issue of personhood as students, as community members, and as ethnographers of their own communities
Differential Privacy and the Accuracy of County-Level Net Migration Estimates
Each decade since the 1950s, demographers have generated high-quality net migration estimates by age, sex, and race for US counties using decennial census data as starting and ending populations. The estimates have been downloaded tens of thousands of times and widely used for planning, diverse applications, and research. Census 2020 should allow the series to extend through the 2010–2020 decade. The accuracy of new estimates, however, could be challenged by differentially private (DP) disclosure avoidance techniques in Census 2020 data products. This research brief estimates the impact of DP implementation on the accuracy of county-level net migration estimates. Using differentially private Census 2010 demonstration data, we construct a hypothetical set of DP migration estimates for 2000–2010 and compare them to published estimates, using common accuracy metrics and spatial analysis. Findings show that based on demonstration data released in 2020, net migration estimates by five-year age groups would only be accurate enough for use in about half of counties. Inaccuracies are larger in counties with populations less than 50,000, among age groups 65 and over, and among Hispanics. These problems are not fully resolved by grouping into broader age groups. Moreover, errors tend to cluster spatially in some regions of the country. Ultimately, the ability to generate accurate net migration estimates at the same level of detail as in the past will depend on the Census Bureau’s allocation of the privacy loss budget
Pre-deployment programmes for building resilience in military and frontline emergency service personnel
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the effectiveness of pre-deployment programmes for building resilience in military and front-line emergency service personnel
WISDOM: the WIYN spectrograph for Doppler monitoring: a NASA-NSF concept for an extreme precision radial velocity instrument in support of TESS
The Kepler mission highlighted that precision radial velocity (PRV) follow-up is a real bottleneck in supporting transiting exoplanet surveys. The limited availability of PRV instruments, and the desire to break the “1 m/s” precision barrier, prompted the formation of a NASA-NSF collaboration ‘NN-EXPLORE’ to call for proposals designing a new Extreme Precision Doppler Spectrograph (EPDS). By securing a significant fraction of telescope time on the 3.5m WIYN at Kitt Peak, and aiming for unprecedented long-term precision, the EPDS instrument will provide a unique tool for U.S. astronomers in characterizing exoplanet candidates identified by TESS. One of the two funded instrument concept studies is led by the Massachusetts Institute of Technology, in consortium with Lincoln Laboratories, Harvard-Smithsonian Center for Astrophysics and the Carnegie Observatories. This paper describes the instrument concept WISDOM (WIYN Spectrograph for DOppler Monitoring) prepared by this team. WISDOM is a fiber fed, environmentally controlled, high resolution (R=110k), asymmetric white-pupil echelle spectrograph, covering a wide 380-1300nm wavelength region. Its R4 and R6 echelle gratings provide the main dispersion, symmetrically mounted on either side of a vertically aligned, vacuum-enclosed carbon fiber optical bench. Each grating feeds two cameras and thus the resulting wavelength range per camera is narrow enough that the VPHG cross-dispersers and employed anti-reflection coatings are highly efficient. The instrument operates near room temperature, and so thermal background for the near-infrared arm is mitigated by thermal blocking filters and a short (1.7μm) cutoff HgCdTe detector. To achieve high resolution while maintaining small overall instrument size (100/125mm beam diameter), imposed by the limited available space within the observatory building, we chose to slice the telescope pupil 6 ways before coupling light into fibers. An atmospheric dispersion corrector and fast tip-tilt system assures maximal light gathering within the 1.2″ entrance aperture. The six octagonal fibers corresponding to each slice of the pupil employ ball-lens double scramblers to stabilize the near- and far-fields. Three apiece are coupled into each of two rectangular fibers, to mitigate modal nose and present a rectilinear illumination pattern at the spectrograph's slit plane. Wavelength solutions are derived from ThAr lamps and an extremely wide coverage dual-channel laser frequency comb. Data is reduced on the fly for evaluation by a custom pipeline, while daily archives and extended scope data reduction products are stored on NExScI servers, also managing archives and access privileges for GTO and GO programs. Note: individual papers, submitted along this main paper, describe the details of subsystems such as the optical design (Barnes et al., 9908-247), the fiber link design (Fűrész et al., 9908-281), and the pupil slicer (Egan et al., 9912-183
The Giant Pillars of the Carina Nebula
Results are presented from a multi-wavelength study of the giant pillars
within the Carina Nebula. Using near-IR data from 2MASS, mid-IR data from MSX,
843MHz radio continuum maps from the MOST, and molecular line and continuum
observations from the SEST, we investigate the nature of the pillars and search
for evidence of ongoing star formation within them. Photodissociation regions
(PDRs) exist across the whole nebula and trace the giant pillars, as well as
many ridges, filaments, and condensations (Av > 7 mag). Morphological
similarities between emission features at 21um and 843MHz adjacent to the PDRs,
suggests that the molecular material has been carved by the intense stellar
winds and UV radiation from the nearby massive stars. In addition, star forming
cores are found at the tips of several of the pillars. Using a stellar density
distribution, several candidate embedded clusters are also found. One is
clearly seen in the 2MASS images and is located within a dense core
(G287.84-0.82). A search for massive young stellar objects and compact HII
regions using mid-IR colour criteria, reveal twelve candidates across the
complex. Grey-body fits to SEDs for four of these objects are suggestive of
OB-stars. We find that massive star formation in the Carina Nebula is occurring
across the whole complex and confirm it has been continuous over the past 3
Myrs.Comment: 14 pages, 10 figures (low resolution), accepted by A&
Economic evaluation of ‘Men on the Move’, a ‘real world’ community-based physical activity programme for men
Background
Physical activity (PA) interventions capable of producing health benefits cost effectively are a public health priority across the Western world. ‘Men on the Move’ (MOM), a community-based PA intervention for men, demonstrated significant health benefits up to 52-weeks (W) post-baseline. This article details the economic evaluation of MOM with a view to determining its cost-effectiveness as a public health intervention to be rolled out nationally in Ireland.
Methods
Cost-effectiveness was determined by comparing the costs (direct and indirect) of the programme to its benefits, which were captured as the impact on quality-adjusted life-years (QALYs). For the benefits, cost–utility analysis was conducted by retrospectively adapting various health-related measures of participants to generate health states using Brazier et al.’s (2002) short form-6D algorithm. This in turn allowed for ‘utility measures’ to be generated, from which QALYs were derived.
Results
Findings show MOM to be cost-effective in supporting an ‘at risk’ cohort of men achieves significant improvements in aerobic fitness, weight loss and waist reduction. The total cost per participant (€125.82 for each of the 501 intervention participants), the QALYs gained (11.98 post-12-W intervention, or 5.3% health improvement per participant) and estimated QALYs ratio costs of €3723 represents a cost-effective improvement when compared to known QALY guidelines.
Conclusions
The analysis shows that the cost per QALY achieved by MOM is significantly less than the existing benchmarks of £20 000 and €45 000 in the UK and Ireland respectively, demonstrating MOM to be cost-effective
On the pulmonary toxicity of oxygen : III. The induction of oxygen dependency by oxygen use
Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Experimental and Molecular Pathology 89 (2010): 36-45, doi:10.1016/j.yexmp.2010.05.004.Oxygen is central to the development of neonatal lung injury. The increase in oxygen exposure of
the neonatal lung during the onset of extrauterine air breathing is an order of magnitude, from a
range of 10-12 to 110-120 Torr. The contributions of oxygen and the volume and pressure
relationships of ventilatory support to lung injury are not easily distinguished in the clinical setting.
Sequential changes in inspired air or 100% oxygen were studied in 536 newborn rabbits without
ventilatory support. Bilateral cervical vagotomies (BCV) were performed at 24 hours post natal to
induce ventilatory distress which eventuates in hyaline membrane disease. The sequences applied
yielded evidence for an induced state of oxygen dependency from oxygen use which was reflected
in differences in survival and the extent of pulmonary injury. The median survival for animals kept
in air throughout was 3 hours. Oxygen before vagotomy or during the first 3 hours afterwards
extended the survival significantly but produced more extensive, more severe, and more rapid lung
lesions. Returning animals to air after prior oxygen exposure reduced the number of survivors past
10 hours and shortened the maximum survival in those groups. These features indicate the
development of a dependency of the defense mechanisms on the availability of oxygen at the higher
level for metabolic and possibly other aspects of the pulmonary and systemic response to injury,
beyond the usual physiological need. Subset analysis revealed additive and latent effects of
oxygen and demonstrated a remarkable rapidity in onset of severe lesions under some
circumstances, illustrating the toxicity of oxygen per se.John A. Hartford Foundation,
New York, N.Y. 10022-171
The role of material, psychosocial and behavioral factors in mediating the association between socioeconomic position and allostatic load (measured by cardiovascular, metabolic and inflammatory markers)
Lower socioeconomic position (SEP), both accumulated across the life course and at different life-stages, has been found to be associated with higher cumulative physiological burden, as measured by allostatic load. This study aimed to identify what factors mediate the association between SEP and allostatic load, as measured through combining cardiovascular, metabolic and inflammatory markers. We explored the role of material, psychological and behavioral factors, accumulated across two periods in time, in mediating the association between SEP and allostatic load. Data are from the West of Scotland Twenty-07 Study, with respondents followed over five waves of data collection from ages 35 to 55 (n=999). Allostatic load was measured by summing nine binary biomarker scores ('1'= in the highest-risk quartile) measured when respondents were 55. years old (wave 5). SEP was measured by a person's accumulated social class over two periods All mediators and SEP were measured at baseline in 1987 and 20. years later and combined to form accumulated measures of risk. Material mediators included car and home ownership, and having low income. The General Health Questionnaire (GHQ-12) was used as the psychosocial mediator. Behavioral mediators included smoking, alcohol consumption, physical activity and diet. Path analysis using linear regressions adjusting for sex were performed for each of the potential mediators to assess evidence of attenuation in the association between lower SEP and higher allostatic load. Analyses by mediator type revealed that renting one's home (approximately 78% attenuation) and having low income (approx. 62% attenuation) largely attenuated the SEP-allostatic load association. GHQ did not attenuate the association. Smoking had the strongest attenuating effect of all health behaviors (by 33%) with no other health behaviors attenuating the association substantially. Material factors, namely home tenure and income status, and smoking have important roles in explaining socioeconomic disparities in allostatic load, particularly when accumulated over time
Quantitative evaluation of recall and precision of CAT Crawler, a search engine specialized on retrieval of Critically Appraised Topics
BACKGROUND: Critically Appraised Topics (CATs) are a useful tool that helps physicians to make clinical decisions as the healthcare moves towards the practice of Evidence-Based Medicine (EBM). The fast growing World Wide Web has provided a place for physicians to share their appraised topics online, but an increasing amount of time is needed to find a particular topic within such a rich repository. METHODS: A web-based application, namely the CAT Crawler, was developed by Singapore's Bioinformatics Institute to allow physicians to adequately access available appraised topics on the Internet. A meta-search engine, as the core component of the application, finds relevant topics following keyword input. The primary objective of the work presented here is to evaluate the quantity and quality of search results obtained from the meta-search engine of the CAT Crawler by comparing them with those obtained from two individual CAT search engines. From the CAT libraries at these two sites, all possible keywords were extracted using a keyword extractor. Of those common to both libraries, ten were randomly chosen for evaluation. All ten were submitted to the two search engines individually, and through the meta-search engine of the CAT Crawler. Search results were evaluated for relevance both by medical amateurs and professionals, and the respective recall and precision were calculated. RESULTS: While achieving an identical recall, the meta-search engine showed a precision of 77.26% (±14.45) compared to the individual search engines' 52.65% (±12.0) (p < 0.001). CONCLUSION: The results demonstrate the validity of the CAT Crawler meta-search engine approach. The improved precision due to inherent filters underlines the practical usefulness of this tool for clinicians
Learning the price of poverty across the UK
© 2017, © The Author(s) 2017. In 2016, the British Educational Research Association (BERA) Commission on Poverty and Policy Advocacy brought together several academics from across the four jurisdictions of the UK already engaged in work on poverty, education and schooling. The aim of this BERA Commission was to build a network of research-active practitioners across the UK and, internationally, to engage in knowledge building about poverty and multiple factors of deprivation as these find expression in education and schooling. The Commission also aimed to facilitate counter discourses to be voiced and articulated in contrast to the dominant pathologising discourses of poor people and their education. The Commission therefore addressed the question: what can research tell us about the ways that different devolved policy contexts impact on the learning and well-being of young people living in poverty? This article describes the methodology used by the Commission to bring together researchers, policymakers, practitioners and children and young people to learn about the price of poverty in education and to reflect on the implications for policy. In so doing, the article addresses some challenges, opportunities and outcomes in terms of knowledge production, as well as implications for critical scholarship, with a focus on poverty and education
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