194 research outputs found
Vibration and buckling of thin-walled composite I-beams with arbitrary lay-ups under axial loads and end moments
A finite element model with seven degrees of freedom per node is developed to study vibration and buckling of thin-walled composite I-beams with arbitrary lay-ups under constant axial loads and equal end moments. This model is based on the classical lamination theory, and accounts for all the structural coupling coming from material anisotropy. The governing differential equations are derived from the Hamilton’s principle. Numerical results are obtained for thin-walled composite I-beams to investigate the effects of axial force, bending moment and fiber orientation on the buckling moments, natural frequencies, and corresponding vibration mode shapes as well as axial-moment-frequency interaction curves
To sit or stand? A preliminary, cross sectional study to investigate if there is a difference in glenohumeral subluxation in sitting or standing in people following stroke
Background: Glenohumeral subluxation (GHS) is a common symptom following stroke. Many therapists postulate that GHS may be reduced if the base of support (BOS) is reduced and the centre of mass (COM) is raised as this requires greater postural muscle activity. However, there is little empirical evidence to support this practice.
Objective: The aim of this preliminary study was to investigate if the amount of GHS alters from sitting to standing.
Study design: A cross sectional, within-subject design in a convenience sample of 15 stroke patients with GHS was utilised.
Methods: A prospective design was used with a single blinded tester who assessed GHS using the calliper method in sitting, standing and on return to sitting. Friedman and post hoc Wilcoxon tests showed that GHS was significantly reduced in standing compared to sitting (p <0.05) but this reduction was not maintained on return to sitting (p = 0.25).
Conclusions: The results of this study are limited by its small size. However, these results indicate that reducing BOS during rehabilitation may improve GHS after stroke. Whilst the maintenance of benefit is not established, these findings suggest that reducing BOS as part of treatment may help patients with GHS. Further research is now required to replicate these results in a larger sample and to directly examine shoulder muscle activity to investigate which muscles may influence GHS in response to changing BOS. Future work could also aim to determine whether the reduction in GHS was directly attributable to a reduced BOS or the effort associated with moving from sitting to standing
General practitioners' opinions on how to improve treatment of mental disorders in primary health care. Interviews with one hundred Norwegian general practitioners
<p>Abstract</p> <p>Background</p> <p>Improvements in treatment of mental disorders are repeatedly called for. General practitioners (GPs) are responsible for the majority of treatment of mental disorders. Consequently, we interviewed GPs about their opinions on how treatment of mental disorders in primary health care contexts could be improved.</p> <p>Methods</p> <p>Among GPs affiliated within the Norwegian reimbursement system, we approached 353, and made contact with 246 GP's. One-hundred of these agreed to participate in our study, and 95 of them expressed opinions on how to improve treatment of mental disorders. The telephone interviews were based on open-ended questions, responses were transcribed continuously, and content analysis was applied. Results are presented both as frequency tables of common responses, and as qualitative descriptions and quotations of opinions.</p> <p>Results</p> <p>Nearly all (95%) of the GPs had suggestions on how to improve treatment of mental disorders in primary health care. Increased capacity in secondary health care was suggested by 59% of GPs. Suggestions of improved collaboration with secondary health care were also common (57%), as were improvements of GPs' skills and knowledge relevant for diagnosing and treating mental disorders (40%) and more time for patients with mental disorders in GP contexts (40%).</p> <p>Conclusions</p> <p>The GPs' suggestions are in line with international research and debate. It is thought-provoking that the majority of GPs call for increased capacity in secondary care, and also better collaboration with secondary care. Some GPs made comparisons to the health care system for physical disorders, which is described as better-functioning. Our study identified no simple short-term cost-effective interventions likely to improve treatment for mental disorders within primary health care. Under-treatment of mental disorders is, however, also associated with significant financial burdens.</p
Condom use and incarceration among STI clinic attendees in the Deep South
Abstract Background Incarceration history is associated with lower rates of condom use and increased HIV risk. Less is known about duration of incarceration and multiple incarcerations’ impact on condom use post-release. Methods In the current study, we surveyed 1,416 adults in Mississippi about their incarceration history and sexual risk behaviors. Generalized estimating equations (GEE) were used to test associations between duration of incarceration, multiple incarcerations, socio-demographic factors, substance use, sexual behavior, and event level condom use at last sex. Results After adjusting for covariates, having been incarcerated for at least 6 months two or more times remained significantly associated with condomless sex. Conclusions This study found a strong, independent relationship between condom use and multiple, long-term incarceration events among patients in an urban STI clinic in the Deep South. The results suggest that duration of incarceration and multiple incarcerations have significant effects on sexual risk behaviors, underscoring the deleterious impact of long prison or jail sentences on population health. Our findings also suggest that correctional health care professionals and post-release providers might consider offering comprehensive sexual and reproductive health services and those providing community care should consider screening for previous incarceration as a marker of risk
Biclustering models for two-mode ordinal data
The work in this paper introduces finite mixture models that can be used to simul-
taneously cluster the rows and columns of two-mode ordinal categorical response data,
such as those resulting from Likert scale responses. We use the popular proportional
odds parameterisation and propose models which provide insights into major patterns
in the data. Model-fitting is performed using the EM algorithm and a fuzzy allocation
of rows and columns to corresponding clusters is obtained. The clustering ability of the
models is evaluated in a simulation study and demonstrated using two real data sets
The Effect of Urban Street Gang Densities on Small Area Homicide Incidence in a Large Metropolitan County, 1994–2002
The presence of street gangs has been hypothesized as influencing overall levels of violence in urban communities through a process of gun–drug diffusion and cross-type homicide. This effect is said to act independently of other known correlates of violence, i.e., neighborhood poverty. To test this hypothesis, we independently assessed the impact of population exposure to local street gang densities on 8-year homicide rates in small areas of Los Angeles County, California. Homicide data from the Los Angeles County Coroners Office were analyzed with original field survey data on street gang locations, while controlling for the established covariates of community homicide rates. Bivariate and multivariate regression analyses explicated strong relationships between homicide rates, gang density, race/ethnicity, and socioeconomic structure. Street gang densities alone had cumulative effects on small area homicide rates. Local gang densities, along with high school dropout rates, high unemployment rates, racial and ethnic concentration, and higher population densities, together explained 90% of the variation in local 8-year homicide rates. Several other commonly considered covariates were insignificant in the model. Urban environments with higher densities of street gangs exhibited higher overall homicide rates, independent of other community covariates of homicide. The unique nature of street gang killings and their greater potential to influence future local rates of violence suggests that more direct public health interventions are needed alongside traditional criminal justice mechanisms to combat urban violence and homicides
The economic impact of alcohol consumption: a systematic review
<p>Abstract</p> <p>Background</p> <p>Information on the economic impact of alcohol consumption can provide important evidence in supporting policies to reduce its associated harm. To date, several studies on the economic costs of alcohol consumption have been conducted worldwide. This study aims to review the economic impact of alcohol worldwide, summarizing the state of knowledge with regard to two elements: (1) cost components included in the estimation; (2) the methodologies employed in works conducted to date.</p> <p>Methods</p> <p>Relevant publications concerning the societal cost of alcohol consumption published during the years 1990-2007 were identified through MEDLINE. The World Health Organization's global status report on alcohol, bibliographies and expert communications were also used to identify additional relevant studies.</p> <p>Results</p> <p>Twenty studies met the inclusion criteria for full review while an additional two studies were considered for partial review. Most studies employed the human capital approach and estimated the gross cost of alcohol consumption. Both direct and indirect costs were taken into account in all studies while intangible costs were incorporated in only a few studies. The economic burden of alcohol in the 12 selected countries was estimated to equate to 0.45 - 5.44% of Gross Domestic Product (GDP).</p> <p>Conclusion</p> <p>Discrepancies in the estimation method and cost components included in the analyses limit a direct comparison across studies. The findings, however, consistently confirmed that the economic burden of alcohol on society is substantial. Given the importance of this issue and the limitation in generalizing the findings across different settings, further well-designed research studies are warranted in specific countries to support the formulation of alcohol-related policies.</p
Openness in Education as a Praxis: From Individual Testimonials to Collective Voices
Why is Openness in Education important, and why is it critically needed at this moment? As manifested in our guiding question, the significance of Openness in Education and its immediate necessity form the heart of this collaborative editorial piece. This rather straightforward, yet nuanced query has sparked this collective endeavour by using individual testimonies, which may also be taken as living narratives, to reveal the value of Openness in Education as a praxis. Such testimonies serve as rich, personal narratives, critical introspections, and experience-based accounts that function as sources of data. The data gleaned from these narratives points to the understanding of Openness in Education as a complex, multilayered concept intricately woven into an array of values. These range from aspects such as sharing, access, flexibility, affordability, enlightenment, barrier-removal, empowerment, care, individual agency, trust, innovation, sustainability, collaboration, co-creation, social justice, equity, transparency, inclusivity, decolonization, democratisation, participation, liberty, and respect for diversity. This editorial, as a product of collective endeavour, invites its readers to independently engage with individual narratives, fostering the creation of unique interpretations. This call stems from the distinctive character of each narrative as they voice individual researchers’ perspectives from around the globe, articulating their insights within their unique situational contexts
- …