1,410 research outputs found
Coupling CFD and visualisation to model the behaviour and effect on visibility of small particles in air
The use of computational fluid dynamics (CFD) and lighting simulation software is becoming commonplace in building design. This study looks at a novel linkage between these two tools in the visualization of droplets or particles suspended in air. CFD is used to predict the distribution of the particles, which is then processed and passed to the lighting simulation tool. The mechanism for transforming CFD contaminant concentration predictions to a form suitable for visual simulation is explained in detail and an example presented which demonstrates this linkage. The CFD-visualisation simulations described in this paper have applications in both automotive and fire safety through the modelling of fog and smoke respectively. Historically, smoke and fog effects have been rendered in images with no attempt at modelling physical reality. The novelty of the work presented in this paper is that, for the first time, an attempt is made to model both the fluid mechanics and optical physics of small particles suspended in a primary fluid
The Land Tenure System in the Newfoundland and Labrador Offshore Regulatory Regime: Review, Analysis and Current Issues
The development of an offshore oiland gas industry in the Gulf ofSt. Lawrence has created, for the first time, the potential for interactions between the Newfoundland and Labrador offshore regulatory regime and other regimes (either the new regime in Quebec or the National Energy Board). As industry participants evaluate where they will spend their exploration dollars, they will need to understand the various regulatory regimes in place. Land tenure in Newfoundland and Labrador is similar to the regime in places subject to the jurisdiction of the National Energy Board. Over the past 25 years, however the decisions of the courts and the guidelines and policies of the Canada-Newfoundland and Labrador Offshore Petroleum Board have given rise to a unique regulatory regime. This paper describes the Newfoundland and Labrador offshore regulatory regime. The types of interests that are available are identified and described. Finally, two current issues in respect to land tenure are identified and discussed
Safety Behaviour in the Construction Industry
The influences on safety standards and employee safety behaviour was analysed on 18 large construction sites on the island of Ireland. The safety management and documentation of these sites was also analysed. The results are discussed at length together with comprehensive recommendations for the industry
One-year Oxford knee scores should be used in preference to 6-month scores when assessing the outcome of total knee arthroplasty
Determining Ages of APOGEE Giants with Known Distances
We present a sample of local red giant stars observed using the New Mexico
State University 1 m telescope with the APOGEE spectrograph, for which we
estimate stellar ages and the age distribution from the high-resolution
spectroscopic stellar parameters and accurate distance measurements from
Hipparcos. The high-resolution (R ~ 23,000), near infrared (H-band, 1.5-1.7
micron) APOGEE spectra provide measurements of the stellar atmospheric
parameters (temperature, surface gravity, [M/H], and [alpha/M]). Due to the
smaller uncertainties in surface gravity possible with high-resolution spectra
and accurate Hipparcos distance measurements, we are able to calculate the
stellar masses to within 40%. For red giants, the relatively rapid evolution of
stars up the red giant branch allows the age to be constrained based on the
mass. We examine methods of estimating age using both the mass-age relation
directly and a Bayesian isochrone matching of measured parameters, assuming a
constant star formation history (SFH). To improve the prior on the SFH, we use
a hierarchical modeling approach to constrain the parameters of a model SFH
from the age probability distribution functions of the data. The results of an
alpha dependent Gaussian SFH model shows a clear relation between age and
[alpha/M] at all ages. Using this SFH model as the prior for an empirical
Bayesian analysis, we construct a full age probability distribution function
and determine ages for individual stars. The age-metallicity relation is flat,
with a slight decrease in [M/H] at the oldest ages and a ~ 0.5 dex spread in
metallicity. For stars with ages < 1 Gyr we find a smaller spread, consistent
with radial migration having a smaller effect on these young stars than on the
older stars.Comment: 14 page, 18 figures, accepted to ApJ with minor revisions, full
electronic table of data available upon publicatio
Age discrimination in the UK labour market. Does race moderate ageism? An experimental investigation
Governments encourage people to work longer in order that pension promises are sustainable as populations age. This approach presupposes that older workers are welcome in the market. This study undertakes a correspondence test to investigate whether ageism is prevalent in the UK at the initial stage of the hiring process. This study adds to the literature by investigating whether race can moderate the relationship between age and labour market outcomes. The results suggest that older people are penalized in the labour market. They have lower access to vacancies and sorting in lower-paid jobs. A minority racial background exacerbates both penalties. These new results call for anti-ageism and anti-racial policy actions in the workplace
Trial-by-Trial Variations in Subjective Attentional State are Reflected in Ongoing Prestimulus EEG Alpha Oscillations
Parieto-occipital electroencephalogram (EEG) alpha power and subjective reports of attentional state are both associated with visual attention and awareness, but little is currently known about the relationship between these two measures. Here, we bring together these two literatures to explore the relationship between alpha activity and participants’ introspective judgments of attentional state as each varied from trial-to-trial during performance of a visual detection task. We collected participants’ subjective ratings of perceptual decision confidence and attentional state on continuous scales on each trial of a rapid serial visual presentation detection task while recording EEG. We found that confidence and attentional state ratings were largely uncorrelated with each other, but both were strongly associated with task performance and post-stimulus decision-related EEG activity. Crucially, attentional state ratings were also negatively associated with prestimulus EEG alpha power. Attesting to the robustness of this association, we were able to classify attentional state ratings via prestimulus alpha power on a single-trial basis. Moreover, when we repeated these analyses after smoothing the time series of attentional state ratings and alpha power with increasingly large sliding windows, both the correlations and classification performance improved considerably, with the peaks occurring at a sliding window size of approximately 7 min worth of trials. Our results therefore suggest that slow fluctuations in attentional state in the order of minutes are reflected in spontaneous alpha power. Since these subjective attentional state ratings were associated with objective measures of both behavior and neural activity, we suggest that they provide a simple and effective estimate of task engagement that could prove useful in operational settings that require human operators to maintain a sustained focus of visual attention
Research and teaching activity in UK occupational physicians
Background:
For all doctors, including occupational physicians (OPs), research and teaching are considered core requirements of medical education and continuing professional development. Academic skills are also vital to evidence-based practice and advancement of occupational health (OH) as a specialty. In recent years, attention has focussed on the declining UK OH academic base and the research– practice gap, and increased practitioner participation in research is encouraged.
Aims:
To establish a baseline of research and teaching activity among UK OPs, identify related barriers and inform strategies to overcome them.
Methods:
An online survey including specific career profile questions derived from consensus following expert panel discussions. It formed part of a larger Delphi study on UK OH research priorities.
Results:
We received 213 responses, about 18% of 1207 practising UK OPs. Of these, 162 (76%) undertook research at some career-point, of which 44 (27%) were currently research-active. Similarly, 154 (72%) undertook teaching at some career-point, of which 99 (64%) were currently teaching-active. Of those who had never undertaken research (n = 51) or teaching (n = 59), 40 and 42% were interested in doing so, respectively. Key barriers were lack of time and opportunity, the former particularly for respondents practising in industry, where ‘commercial’ demands take priority, rather than healthcare.
Conclusions:
This study establishes a benchmark of academic activity among UK OPs and identifies related barriers. These ‘target’ barriers can shape research funding priorities and education to increase participation and develop the UK OH academic base
Disruptive technology for vector control: the Innovative Vector Control Consortium and the US Military join forces to explore transformative insecticide application technology for mosquito control programmes
Malaria vector control technology has remained largely static for decades and there is a pressing need for innovative control tools and methodology to radically improve the quality and efficiency of current vector control practices. This report summarizes a workshop jointly organized by the Innovative Vector Control Consortium (IVCC) and the Armed Forces Pest Management Board (AFPMB) focused on public health pesticide application technology. Three main topics were discussed: the limitations with current tools and techniques used for indoor residual spraying (IRS), technology innovation to improve efficacy of IRS programmes, and truly disruptive application technology beyond IRS. The group identified several opportunities to improve application technology to include: insuring all IRS programmes are using constant flow valves and erosion resistant tips; introducing compression sprayer improvements that help minimize pesticide waste and human error; and moving beyond IRS by embracing the potential for new larval source management techniques and next generation technology such as unmanned “smart” spray systems. The meeting served to lay the foundation for broader collaboration between the IVCC and AFPMB and partners in industry, the World Health Organization, the Bill and Melinda Gates Foundation and others
Total knee arthroplasty in patients with severe obesity:outcomes of standard keeled tibial components versus stemmed universal base plates
Background: Patients with severe obesity [body mass index (BMI) ≥ 40 kg/m2] potentially overload the tibial component after total knee arthroplasty (TKA), risking tibial subsidence. Using a cemented single-radius cruciate-retaining TKA design, this study compared the outcomes of two tibial baseplate geometries in patients with BMI ≥ 40 kg/m2: standard keeled (SK) or universal base plate (UBP), which incorporates a stem. Methods: This was a retrospective, single-centre cohort study with minimum 2 years follow-up of 111 TKA patients with BMI ≥ 40 kg/m2: mean age 62.2 ± 8.0 (44–87) years, mean BMI 44.3 ± 4.6 (40–65.7) kg/m2 and 82 (73.9%) females. Perioperative complications, reoperations, alignment and patient-reported outcomes (PROMS): EQ-5D, Oxford Knee Score (OKS), Visual Analogue Scale (VAS) pain score and satisfaction were collected preoperatively, and at 1 year and final follow-up postoperatively. Results: Mean follow-up was 4.9 years. SK tibial baseplates were performed in 57 and UBP in 54. There were no significant differences in baseline patient characteristics, post-operative alignment, post-operative PROMs, reoperations or revisions between the groups. Three early failures requiring revision occurred: two septic failures in the UBP group and one early tibial loosening in the SK group. Five-year Kaplan–Meier survival for the endpoint mechanical tibial failure was SK 98.1 [94.4–100 95% confidence interval (CI)] and UBP 100% (p = 0.391). Overall varus alignment of the limb (p = 0.005) or the tibial component (p = 0.031) was significantly associated with revision and return to theatre. Conclusions: At early to mid-term follow-up, no significant differences in outcomes were found between standard and UBP tibial components in patients with BMI ≥ 40 kg/m2. Varus alignment of either tibial component or the limb was associated with revision and return to theatre.</p
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