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The goal of this study was to reconstruct the historical respirable silica (RS) and respirable dust (RD) exposures of workers in the Minnesota taconite industry from 1955 to 2010 as part of several epidemiological studies for assessing the association between exposure to components of taconite dusts and the development of respiratory diseases. A job-exposure matrix (JEM) was developed that uses 9127 RS and 19 391 RD occupational hygiene historical measurements. Historical RS and RD data were extracted from several sources and were grouped into seven mines and then into eight departments [Concentrating, Crushing, Janitor, Mining, Office/control room, Pelletizing, Shop (mobile), and Shop (stationary)]. Within each department, we applied a two-level random-intercept regression model which assumes that the natural log of Y (RD or RS concentration) changes over time at a constant rate. Among all predicted RD and RS values, we found that larger RD values were located in the following departments: Crushing, Concentrating, Pelletizing, and Shop (mobile). Larger RS values were located only in either Crushing or Shop (mobile). The annual rates of change for historical RD and RS exposures were between −3.3 and 3.2%. The silica percentage in the dust varied by mine/department with the highest value of 29.3% in Mine F (Crushing) and the lowest value of 2.1% in Mine B (Pelletizing). The predicted historical RD and RS arithmetic mean exposures ranged between <0.075 and 3.14 mg m−3, and between <0.005 and 0.36 mg m−3, respectively. The result of this study is a JEM by mine, department, and year for RD and RS for epidemiological studies. [ABSTRACT FROM AUTHOR]

Studies in environmental epidemiology and of occupational cohorts have implicated the effects of fine particulates with increased risk of cardiovascular diseases. Motivated by this evidence, we conducted an ambient air monitoring campaign to characterize fine aerosol concentrations around various taconite ore processes in six taconite mines in northeastern Minnesota. The ore processes were first categorized into 16 broad work areas/buildings. We then took air samples at 91 fixed locations using an array of direct-reading instruments to obtain measurements of mass (PM2.5 or particles with aerodynamic diameter <2.5 µm, and respirable particulate matter or RPM), alveolar-deposited surface area (ADSA), and particle number (PN) concentrations. At each location, a respirable gravimetric pump (which was used for calibration purposes) and the instruments measured the ambient dust level for 4 h producing ~240 1-min averaging real-time measurements. To analyze these data, we fit a Bayesian hierarchical model with an autoregressive order 1 correlation structure to estimate pooled concentrations for the 16 work areas/buildings while accounting for temporal correlation. PM2.5 and RPM average ambient concentrations were highly correlated to each other (Pearson's correlation = 0.98), followed by ADSA and PN correlation (R = 0.77). Office and control room areas were found to have the lowest concentrations in all four metrics when compared to other groups. Distinguishing between concentration levels among the remaining groups was more difficult due to the high uncertainty associated with the geometric mean estimates. The geometric standard deviation within location (GSDWL) generally ranged from 1 to 3 for all exposure metrics, except for a few locations that may have had changes in the work activities that generated the observed peaks and variability during the sampling duration. The geometric standard deviation between locations estimates were generally higher than GSDWL, which may indicate larger variability in the processes/activities between locations within each broad work area/building. Future work may look into whether it is feasible to use area measurements for epidemiological investigation and use personal measurements (if available) to validate such approach. [ABSTRACT FROM AUTHOR]

Research on social work in the criminal justice system was well represented in the social work literature until the 1990s. Since then, changes in the organisation, training and research base of probation practice, particularly in England and Wales, have all contributed to a separation between probation research and the mainstream social work research literature. However, recent probation research, by focusing on individual practice skills and on the quality of relationships, is producing findings which resonate with traditional social work concerns. The study presented here, based on analysis of videotaped interviews between probation staff and the people they are supervising, shows what skills are used and the effects of skilled supervision. People supervised by more skilled staff were significantly less likely to be reconvicted over a two-year follow-up, and the most effective supervisors combined good relationship skills with a range of 'structuring' or change-promoting skills. In effect, this can be regarded as a test of the impact of social work skills used by probation staff and suggests that a closer relationship between mainstream social work research and probation research could be productive for both. [ABSTRACT FROM AUTHOR]

There is widespread evidence of different outcomes for people from different ethnic groups in the British criminal justice system, but studies attempting to reveal discrimination by documenting different outcomes for offenders who are similar except for ethnicity have suffered from the difficulty of controlling for all possibly relevant characteristics. This article uses an alternative methodology: by reviewing British studies by the authors and others in which risk-assessed offenders have received similar disposals, it shows that in almost all cases the minority ethnic offenders have been assessed as presenting, on average, a lower score than white British offenders on various risk–need instruments. In most studies, this difference is significant. This suggests that members of minority ethnic groups are likely to receive, on average, more severe sentences than white offenders assessed as presenting similar levels of risk and criminogenic need, and therefore provides support for studies that have used the conventional methodology, as well as suggesting that risk–need assessment data can help social workers, probation officers and other professionals to monitor discrimination. [ABSTRACT FROM PUBLISHER]

Recently, the appropriateness of using the ‘mass concentration’ metric for ultrafine particles has been questioned and surface area (SA) or number concentration metrics has been proposed as alternatives. To assess the abilities of various exposure metrics to distinguish between different exposure zones in workplaces with nanoparticle aerosols, exposure concentrations were measured in preassigned ‘high-’ and ‘low-’exposure zones in a restaurant, an aluminum die-casting factory, and a diesel engine laboratory using SA, number, and mass concentration metrics. Predetermined exposure classifications were compared by each metric using statistical parameters and concentration ratios that were calculated from the different exposure concentrations. In the restaurant, SA and fine particle number concentrations showed significant differences between the high- and low-exposure zones and they had higher contrast (the ratio of between-zone variance to the sum of the between-zone and within-zone variances) than mass concentrations. Mass concentrations did not show significant differences. In the die cast facility, concentrations of all metrics were significantly greater in the high zone than in the low zone. SA and fine particle number concentrations showed larger concentration ratios between the high and low zones and higher contrast than mass concentrations. None of the metrics were significantly different between the high- and low-exposure zones in the diesel engine laboratory. The SA and fine particle number concentrations appeared to be better at differentiating exposure zones and finding the particle generation sources in workplaces generating nanoparticles. Because the choice of an exposure metric has significant implications for epidemiologic studies and industrial hygiene practice, a multimetric sampling approach is recommended for nanoparticle exposure assessment. [ABSTRACT FROM AUTHOR]

Background: To investigate the association between breastfeeding duration and socio-economic status as measured by the English and Welsh Indices of Multiple Deprivation (IMD). Methods: Total 216 multiparous women whose youngest or only child was between 6 and 24 months completed a retrospective questionnaire study of infant feeding between birth and 26 weeks. Measurements included breast-feeding history; socio-economic demography and IMD. Results: Breastfeeding duration was associated with levels of multiple deprivation in both English and Welsh samples. Deprivation level and breastfeeding duration were associated with traditional indicators of socio-economic status. When considered in combination with other socio-economic indicators of breastfeeding duration, the deprivation level remained a strong predictor of breastfeeding duration over and above other socio-economic measures. Conclusions: Deprivation, as assessed by the IMD is predictive of breastfeeding duration. Postcode and thus deprivation level can be used as a non-intrusive way to identify women most at risk of low breastfeeding rates. Service provision can be targeted directly at women in areas recognized at being high in deprivation. [ABSTRACT FROM AUTHOR]

This study reports the results of a numerical investigation and an experimental study on a round nozzle virtual impactor (VI) operated in two different modes. The newly proposed sampler, the semivolatile aerosol dichotomous sampler (SADS), was studied to overcome some of the problems of existing personal sampling methods such as evaporative loss during filter sampling. The main difference between VIs and the SADS was the inverted flow ratio between the major flow and the minor flow. Sampling in the SADS settings gives a lower cutsize in both numerical simulations and experimental results. Whereas the 50% separation efficiency for a VI occurred in numerical simulations when the square root of Stokes number equaled 0.97, the 50% efficiency for the same sampler run in the SADS settings occurred when the square root of the Stokes number was 0.27. The back pressure on each flow direction was studied and greater pressure drop was observed through the vapor flow in SADS settings. Sampling using a SADS was more effective than traditional filter methods because of its smaller cutsize, instant separation of vapor from particles and reduced particle losses. [ABSTRACT FROM PUBLISHER]

Metalworking fluid emulsion formulations produced from vegetable oils may be less toxic and may reduce disposal costs when compared with fluids formulated with petroleum-based oils. Experiments were performed on experimental emulsions made with unmodified and modified soybean oils to measure rates of mist production by impaction, centrifugal force and evaporation/recondensation mechanisms. Results were compared with measurements made using a commercial metalworking fluid emulsion formulated using vegetable oil and another made from mineral oil. The results indicated that most of the experimental fluids produced about the same amount of mist as the commercial fluids by impaction and more mist than the petroleum-based fluid by centrifugal force. However, an air-oxidized modified soy oil produced less mist by impaction than the petroleum-based fluid and about the same by centrifugal force. The experimental fluids produced between 30 and 90% less mist than the commercial fluids by evaporation/recondensation. The air-oxidized soybean oil was the most promising candidate among the experimental fluids for further testing in more realistic machining conditions. [ABSTRACT FROM AUTHOR]

Fibrous filters are used for environmental and occupational mist sampling and industrial mist collection. If compounds in the filtered droplets are volatile or semi-volatile, they may evaporate into the gas passing through the filter. In sampling applications, failure to properly account for evaporation of collected mist will lead to mist concentration estimates that are low. In control applications, volatilization of filtered droplets may release vapors that are harmful to workers or the public. Also, vapor emitted from mist filters may recondense as a hazardous aerosol or on surfaces to pose a safety or housekeeping problem. Droplets collected by fibrous filters coalesce into larger drops that reside on the fibers. Results from a numerical model developed to predict evaporation from these drops agree favorably with experimental data. Measurements and numerical predictions show that a gas stream leaving a wetted fibrous filter can be saturated with the vapor of semi-volatile compounds retained on the filter. In some situations, the model indicates that the gas stream will be saturated before it passes 0.1mm into a wetted filter. If the liquid retained on a filter is a pure compound, the vapor concentration leaving the filter is constant when initially clean air passes through. If the liquid is multicomponent, the downstream vapor concentration in previously uncontaminated air will decrease with time as the more volatile components evaporate preferentially. Fluctuations in incoming mist and vapor concentrations can enhance evaporation because more retained liquid will volatilize when incoming vapor concentrations are low. [ABSTRACT FROM PUBLISHER]

Evaluates the operation of an early release program known as Automatic Conditional Release (ACR) in Great Britain. Discussion of the contradictory forces which led to the introduction of the ACR scheme; Reactions of prisoners and licensees on the ACR scheme; Practitioners' attempt of adapting traditional concepts of throughcare.

Reports the results from the study assessing the impact of introducing pre-sentence reports in a wide range of cases in the Crown Courts. Variable quality of probation officers' reports; Level of agreement between the researchers' assessments of quality and those made by sentencers in the Crown Courts; Impact of low and high reports on the sentencing process.

During the months immediately preceding the implementation of the 1991 Criminal Justice Act the Home Office commissioned a study of quality assurance and quality control procedures used by probation services in their work on social inquiry reports and in their preparation for the change to pre-sentence reports. This paper summarizes the results of that study, which included a survey of current practice in probation services and the development of a quality control instrument for assessing the quality of pre-sentence reports. It is emphasized that the views expressed in this paper are those of the authors and not necessarily those of the Home Office. [ABSTRACT FROM AUTHOR]

This paper reports interim and largely positive results from the continuing evaluation of 'Straight Thinking on Probation', a substantial intensive probation programme in Mid-Glamorgan based on the work of Robert Ross et al. (1988) in Canada, The potential effectiveness of this type of programme is then discussed in relation to the influential model of the probation service's role advanced by Bottoms and McWilliams in their 1979 'non-treatment paradigm'. Are such programmes 'treatment', based on a model of offender pathology and therefore in conflict with the paradigm, or are they 'help', based on a model of empowerment? An attempt to answer this question also requires consideration of how far the 'non-treatment paradigm' was itself a response to perceived ineffectiveness requiring revision in the light of new evidence. It is argued that such revision need not threaten the underlying moral philosophy of the paradigm. [ABSTRACT FROM AUTHOR]