12,314 research outputs found
Exposure of U.S. workers to environmental tobacco smoke.
The concentrations of environmental tobacco smoke (ETS) to which workers are exposed have been measured, using nicotine or other tracers, in diverse workplaces. Policies restricting workplace smoking to a few designated areas have been shown to reduce concentrations of ETS, although the effectiveness of such policies varies among work sites. Policies that ban smoking in the workplace are the most effective and generally lower all nicotine concentrations to less than 1 microg/m3; by contrast, mean concentrations measured in workplaces that allow smoking generally range from 2 to 6 microg/m3 in offices, from 3 to 8 microg/m3 in restaurants, and from 1 to 6 microg/m3 in the workplaces of blue-collar workers. Mean nicotine concentrations from 1 to 3 microg/m3 have been measured in the homes of smokers. Furthermore, workplace concentrations are highly variable, and some concentrations are more than 10 times higher than the average home levels, which have been established to cause lung cancer, heart disease, and other adverse health effects. For the approximately 30% of workers exposed to ETS in the workplace but not in the home, workplace exposure is the principal source of ETS. Among those with home exposures, exposures at work may exceed those resulting from home. We conclude that a significant number of U.S. workers are exposed to hazardous levels of ETS
The experiences of African immigrant mothers living in the United Kingdom with a child diagnosed with an autism spectrum disorder: an interpretive phenomenological analysis
Interpretive phenomenological analysis was used to investigate the experiences of six African immigrant mothers living in the United Kingdom with a child diagnosed with an Autism Spectrum Disorder (ASD). The mothers took part in one-off, semi-structured interviews.
Four themes were identified: caring for a child we did not expect, the pain of stigma and rejection, frameworks of meaning, and negotiating conflicting cultural beliefs. Many aspects of the mothers’ experiences appear related to their position as immigrants from cultures with contrasting belief systems regarding child development and disability. Conflicts between African cultural beliefs and a western, medical understanding of ASD appeared to create a feeling of cognitive dissonance for the mothers.
The strategies used to negotiate this appear to map onto Berry’s acculturation strategies, suggesting that the experience of having a child with ASD impacts upon the acculturation process. Implications for clinical practice and policy are discussed
Experimental and numerical study of error fields in the CNT stellarator
Sources of error fields were indirectly inferred in a stellarator by
reconciling computed and numerical flux surfaces. Sources considered so far
include the displacements and tilts (but not the deformations, yet) of the four
circular coils featured in the simple CNT stellarator. The flux surfaces were
measured by means of an electron beam and phosphor rod, and were computed by
means of a Biot-Savart field-line tracing code. If the ideal coil locations and
orientations are used in the computation, agreement with measurements is poor.
Discrepancies are ascribed to errors in the positioning and orientation of the
in-vessel interlocked coils. To that end, an iterative numerical method was
developed. A Newton-Raphson algorithm searches for the coils' displacements and
tilts that minimize the discrepancy between the measured and computed flux
surfaces. This method was verified by misplacing and tilting the coils in a
numerical model of CNT, calculating the flux surfaces that they generated, and
testing the algorithm's ability to deduce the coils' displacements and tilts.
Subsequently, the numerical method was applied to the experimental data,
arriving at a set of coil displacements whose resulting field errors exhibited
significantly improved quantitative and qualitative agreement with experimental
results.Comment: Special Issue on the 20th International Stellarator-Heliotron
Worksho
Reviving botany in the curriculum: The botanical journey of two Western Australian early childhood teachers
Environmental education across the early years has become increasingly important in Australia since the implementation of the Early Years Learning Framework and the Australian Curriculum. These documents promote a connection to nature for young children as well as environmental responsibility. In Western Australia, large areas of natural environments are bush spaces, accessible by young children, families and schools. There is no existing research investigating early childhood teacher’s knowledge of plants in these bush spaces and the utilisation of these spaces in teaching botany as part of their teaching practice. The discussion in this article examines part of a larger year-long multi-site case study of the changes in the botanical understanding of two early childhood teachers of children aged 5–8 years, in Western Australian schools both before and after the Mosaic Approach, botanical practices and Indigenous knowledges were incorporated into their teaching practice. This article focuses on the changes of botanical literacies of the early childhood teachers specifically. The findings suggest that using inquiry-based and place-based methods and including First Nations Peoples’ perspectives about plants whilst teaching in the bush can significantly increase the plant knowledge and understanding of teachers, as well their own scientific and botanical literacies
Psychometric testing of a german version of the evaluation of daily activity questionnaire in rheumatoid arthritis
Background: The Evaluation of Daily Activity Questionnaire (EDAQ) is a patient reported outcome (PRO) of activity limitations. The English EDAQ is reliable, valid and a comprehensive measure of the commonest problems experienced by people with rheumatoid arthritis (RA) and musculoskeletal conditions [1,2]. It includes 138 items in 14 ‘domains’ (Eating/ Drinking; Personal Care; Dressing; Bathing; Cooking; Moving Indoors; House Cleaning; Laundry; Moving and Transfers; Moving Outdoors; Gardening/Household Maintenance; Caring; Leisure/ Social Activities). All items are scored on a 0-3 scale (no difficulty to unable to do). There is no similar measure available in German. PROs must be tested in target languages and conditions, prior to use, to ensure validity and reliability.
Objectives: To linguistically validate a German EDAQ and test it’s reliability and validity in German-speaking people with RA.
Methods: The English EDAQ was forward-backward translated to German. Cognitive debriefing interviews were conducted and the German EDAQ developed. Participants from a Rheumatology clinic (Switzerland) and arthritis patient organizations (Switzerland, Germany, Austria) then completed postal questionnaires including: demographic questions, German EDAQ, Health Assessment Questionnaire (HAQ), SF36v2, RA Quality of Life scale (RAQOL), and a hand pain numeric rating scale (NRS). Three weeks later, the EDAQ was mailed again. Test-retest reliability of domain scores, and validity of the 14 German EDAQ domains against the other measures, were evaluated using nonparametric correlations. Internal consistency was tested using Cronbach’s alpha.
Results: Six German-speaking people with RA were interviewed, recommended changes reviewed by the expert panel and the German EDAQ agreed. 163 people then completed questionnaires: 145 women and 18 men; mean age = 52.84 (SD14.94) years; mean RA duration = 15.73 years (SD12.12). 85(45%) were employed; 21 had children <18y at home. Median pain score = 4 (IQR 2-6) and fatigue = 5 (IQR 3-7).
107 (65%) completed a second questionnaire. Test-retest reliability of total domain scores was excellent for all domains (rs= 0.80 - 0.93). Internal consistency was high in all domains: Cronbach’s alpha= 0.84 – 0.96. All EDAQ domains (except Caring) correlated significantly (p<0.001) with: HAQ rs= 0.73- 0.87; SF36v2 (Physical Function) rs= -0.61 to -0.84; SF36v2 Bodily Pain rs=-0.53 to -0.65; SF36v2 (Vitality) rs= -0.27 to-0.31; RAQOL rs= 0.55-0.68; and hand pain rs=0.43-0.52. Correlations were lower in the ‘Caring’ domain due to the smaller sample size (n=77), although mostly still significant (p<0.01; rs=0.25 to 0.42; except Sf36v2 Vitality = -0.10 non- significant).
Conclusions: The German EDAQ is a valid and reliable measure of daily activity in people with RA. Either the whole EDAQ or individual domains can be used in clinical practice to identify clients’ daily activity problems and help find solutions, or as an outcome measure in research and audit. A User Manual is available [3].
References: [1] Hammond et al (2015) Rheumatology 54:1605-1615; [2] Hammond et al (2017) Disabil Rehabil DOI: 10.1080/09638288.2017.1323027 [3] Hammond A et al. The EDAQ User Manual v2. 2016: https://usir.salford.ac.uk/30752/</a
IIaO ultraviolet and nuclear emulsion films responses to orbital flights on STS-3, STS-7, STS-8, and STS-40
Two types of film were flown on STS-40 space shuttle mission in June 1991. The IIaO special purpose ultraviolet film showed continued desensitization because of various thermal and cosmic ray interactions. The films were exposed to the space orbital environment for 9 days. There were several built-in launch pad delays of the shuttle mission. However, there was adequate monitoring of the temperature variations on board the shuttle that allowed for adequate knowledge of the thermal film history. This IIaO film was flown on the ASTRO I mission and is currently slated for use with the ASTRO II mission. A 50 micron thick IIIford Nuclear emulsion film was also placed on a 175 micron polyester base. The exposure to space produced several cosmic ray interactions that were analyzed and measured using Digital Image Processing techniques. This same nuclear emulsion film was flown on STS-8 and produced a similar number of cosmic ray and thermal interactions. From previous experiments of film using various laboratory electromagnetic radiation sources (e.g., alpha, beta, and neutron particles), we have been able to infer the possible oribtal interactions of both IIaO and nuclear emulsion films. The characteristic responses of IIaO on STS-40 compared favorably to the results obtained from previous STS-7 and STS-8 gas can experiments. The results indicate sufficient evidence correlating increased density on the film with possible cosmic ray, thermal and shuttle out gassing interactions
Health effects of gasoline exposure. I. Exposure assessment for U.S. distribution workers.
Personal exposures were estimated for a large cohort of workers in the U.S. domestic system for distributing gasoline by trucks and marine vessels. This assessment included development of a rationale and methodology for extrapolating vapor exposures prior to the availability of measurement data, analysis of existing measurement data to estimate task and job exposures during 1975-1985, and extrapolation of truck and marine job exposures before 1975. A worker's vapor exposure was extrapolated from three sets of factors: the tasks in his or her job associated with vapor sources, the characteristics of vapor sources (equipment and other facilities) at the work site, and the composition of petroleum products producing vapors. Historical data were collected on the tasks in job definitions, on work-site facilities, and on product composition. These data were used in a model to estimate the overall time-weighted-average vapor exposure for jobs based on estimates of task exposures and their duration. Task exposures were highest during tank filling in trucks and marine vessels. Measured average annual, full-shift exposures during 1975-1985 ranged from 9 to 14 ppm of total hydrocarbon vapor for truck drivers and 2 to 35 ppm for marine workers on inland waterways. Extrapolated past average exposures in truck operations were highest for truck drivers before 1965 (range 140-220 ppm). Other jobs in truck operations resulted in much lower exposures. Because there were few changes in marine operations before 1979, exposures were assumed to be the same as those measured during 1975-1985. Well-defined exposure gradients were found across jobs within time periods, which were suitable for epidemiologic analyses
Frequency Following Imaging of Electric Fields from Resonant Superconducting Devices using a Scanning Near-Field Microwave Microscope
We have developed a scanning near-field microwave microscope that operates at
cryogenic temperatures. Our system uses an open-ended coaxial probe with a 200
mm inner conductor diameter and operates from 77 to 300 K in the 0.01-20 GHz
frequency range. In this paper, we present microwave images of the electric
field distribution above a Tl2Ba2CaCu2O8 microstrip resonator at 77 K, measured
at several heights. In addition, we describe the use of a frequency-following
circuit to study the influence of the probe on the resonant frequency of the
device.Comment: 4 pages, postscript file with 6 figures conference proceeding for the
Applied Superconductivity Conference 199
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