7 research outputs found

    The Effect of Maximum Coarse Aggregate Size on the Compressive Strength of Concrete Produced in Ghana

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    An experiment was conducted to determine the effect of different sizes of machine crushed gneisses used in Ghana for concrete production on the compressive strength of concrete. Coarse aggregate samples of maximum sizes of 10mm, 14mm and 20mm were used to produce concrete at constant water/cement ratio of 0.63. In all the experiments, the concreting procedures and materials were kept constant whiles the maximum coarse aggregate sizes were varied. A total of 36 concrete cubes were crushed at 7, 14, 21 and 28 days to determine their compressive strengths.The results show that the smallest coarse aggregate size gave the highest compressive strength and lowest slump at constant water/cement ratio.  A regression analysis also shows that the relationship between the maximum coarse aggregate size and the compressive strength follows a polynomial with R2= 1; indicating that the model is reliable. The optimum maximum coarse aggregate size for the best compressive strength of 28 day concrete was therefore found to be 8mm for the water/cement ratio of 0.63. The analysis further shows that as heterogeneity increases the compressive strength of concrete reduces. Keywords: Gneiss, compressive strength, aggregate sizes, slump, heterogeneity.

    Modifiable and emerging risk factors for type 2 diabetes in Africa: a systematic review and meta-analysis protocol

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    BACKGROUND: Type 2 diabetes mellitus (T2DM) remains a public health problem in low-income countries, including African countries. Risk factors of this disease in Africa are still unclear. This study will examine the modifiable and emerging risk factors associated with T2DM in Africa. METHODOLOGY: The study will include a systematic review and meta-analysis of published and unpublished empirical studies, reporting quantitative data only. We will conduct a search on scientific databases (e.g. Global Health), general online search engines (e.g. Google Scholar) and key websites for grey literature using a combination of key countries/geographic terms, risk factors (e.g. overweight/obesity) and T2DM (including a manual search of the included reference lists). We will use the Comprehensive Meta-Analysis Software (CMA) version 2.0 for data management and analysis. This protocol follows the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). DISCUSSION: The systematic review and meta-analysis will provide a robust and reliable evidence base for policy makers and future research. This may help with identifying and implementing more cost-effective diabetes prevention strategies and improved resource allocation.<br /

    Racism in Australia : a protocol for a systematic review and meta-analysis

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    Background: Racism has been identified as a major source of injustice and a health burden in Australia and across the world. Despite the surge in Australian quantitative research on the topic, and the increasing recognition of the prevalence and impact of racism in Australian society, the collective evidence base has yet to be comprehensively reviewed or meta-analysed. This protocol describes the first systematic review and meta-analysis of racism in Australia at the national level, focussing on quantitative studies. The current study will considerably improve our understanding of racism, including its manifestations and fluctuation over time, variation across settings and between groups, and associations with health and socio-economic outcomes. Methods: The research will consist of a systematic literature review and meta-analysis. Searches for relevant studies will focus on the social and health science databases CINAHL, PsycINFO, PubMed and Scopus. Two reviewers will independently screen eligible papers for inclusion and extract data from included studies. Studies will be included in the review and meta-analysis where they meet the following criteria: (1) report quantitative empirical research on self-reported racism in Australia, (2) report data on the prevalence of racism, or its association with health (e.g. mental health, physical health, health behaviours) or socio-economic outcomes (e.g. education, employment, income), and (3) report Australian data. Measures of racism will focus on study participants’ self-reports, with a separate analysis dedicated to researcher-reported measures, such as segregation and differential outcomes across racial/ethnic groups. Measures of health and socio-economic outcomes will include both self-reports and researcher-reported measures, such as physiological measurements. Existing reviews will be manually searched for additional studies. Study characteristics will be summarised, and a meta-analysis of the prevalence of racism and its associations will be conducted using random effects models and mean weighted effect sizes. Moderation and subgroup analyses will be conducted as well. All analyses will use the software CMA 3.0. Discussion: This study will provide a novel and comprehensive synthesis of the quantitative evidence base on racism in Australia. It will answer questions about the fluctuation of racism over time, its variation across settings and groups, and its relationship with health and socio-economic outcomes. Findings will be discussed in relation to broader debates in this growing field of research and will be widely disseminated to inform anti-racism research, action and policy nationally. Systematic review registration: PROSPERO CRD42021265115

    Sociocultural factors and perceptions associated with type 2 diabetes among sub-Saharan African migrants in Melbourne, Victoria

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    Aim: To explore how non-diabetic sub-Saharan African migrants residing in Melbourne, construct and interpret type 2 diabetes mellitus (T2DM) and its risk factors and to provide an evidence-based theoretical framework to inform community-based prevention programs. Methods: Seven focus group discussions (two with women only, two with men only and three of mixed gender) were carried out among Ghanaian, Zimbabwean, Sudanese and Burundian migrants living in Melbourne (n = 61; age range: 18 to 61 years). Results: Three distinct themes emerged: not paying much attention to the threat of T2DM and othering; T2DM being outside the individuals\u27 control; and entrapment within rich industrialised culture and lifestyle. Participants perceived T2DM to be a disease of the wealthy caused by intake of too much sugar and sedentary behaviour, which were particularly compounded by lifestyle-related changes upon migration to an industrialised country. However, they also perceived T2DM to be associated with bad luck. Conclusions: Culturally competent prevention and education programs are needed to increase health literacy and dispel religious and cultural myths about T2DM among sub-Saharan African migrants

    Optimising the implementation of digital-supported interventions for the secondary prevention of heart disease: a systematic review using the RE-AIM planning and evaluation framework

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    Abstract Background mHealth technologies are now widely utilised to support the delivery of secondary prevention programs in heart disease. Interventions with mHealth included have shown a similar efficacy and safety to conventional programs with improvements in access and adherence. However, questions remain regarding the successful wider implementation of digital-supported programs. By applying the Reach-Effectiveness-Adoption-Implementation-Maintenance (RE-AIM) framework to a systematic review and meta-analysis, this review aims to evaluate the extent to which these programs report on RE-AIM dimensions and associated indicators. Methods This review extends our previous systematic review and meta-analysis that investigated the effectiveness of digital-supported programs for patients with coronary artery disease. Citation searches were performed on the 27 studies of the systematic review to identify linked publications that reported data for RE-AIM dimensions. All included studies and, where relevant, any additional publications, were coded using an adapted RE-AIM extraction tool. Discrepant codes were discussed amongst reviewers to gain consensus. Data were analysed to assess reporting on indicators related to each of the RE-AIM dimensions, and average overall reporting rates for each dimension were calculated. Results Searches found an additional nine publications. Across 36 publications that were linked to the 27 studies, 24 (89%) of the studies were interventions solely delivered at home. The average reporting rates for RE-AIM dimensions were highest for effectiveness (75%) and reach (67%), followed by adoption (54%), implementation (36%) and maintenance (11%). Eleven (46%) studies did not describe relevant characteristics of their participants or of staff involved in the intervention; most studies did not describe unanticipated consequences of the intervention; the ongoing cost of intervention implementation and maintenance; information on intervention fidelity; long-term follow-up outcomes, or program adaptation in other settings. Conclusions Through the application of the RE-AIM framework to a systematic review we found most studies failed to report on key indicators. Failing to report these indicators inhibits the ability to address the enablers and barriers required to achieve optimal intervention implementation in wider settings and populations. Future studies should consider alternative hybrid trial designs to enable reporting of implementation indicators to improve the translation of research evidence into routine practice, with special consideration given to the long-term sustainability of program effects as well as corresponding ongoing costs. Registration PROSPERO—CRD42022343030
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