292 research outputs found

    Rodent malaria-resistant strains of the mosquito, Anopheles gambiae, have slower population growth than -susceptible strains

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    <p>Abstract</p> <p>Background</p> <p>Trade-offs between anti-parasite defence mechanisms and other life history traits limit the evolution of host resistance to parasites and have important implications for understanding diseases such as malaria. Mosquitoes have not evolved complete resistance to malaria parasites and one hypothesis is that anti-malaria defence mechanisms are costly.</p> <p>Results</p> <p>We used matrix population models to compare the population growth rates among lines of <it>Anopheles gambiae </it>that had been selected for resistance or high susceptibility to the rodent malaria parasite, <it>Plasmodium yoelii nigeriensis</it>. The population growth rate of the resistant line was significantly lower than that of the highly susceptible and the unselected control lines, regardless of whether mosquitoes were infected with <it>Plasmodium </it>or not. The lower population growth of malaria-resistant mosquitoes was caused by reduced post blood-feeding survival of females and poor egg hatching.</p> <p>Conclusion</p> <p>With respect to eradicating malaria, the strategy of releasing <it>Plasmodium</it>-resistant <it>Anopheles </it>mosquitoes is unlikely to be successful if the costs of <it>Plasmodium</it>-resistance in the field are as great as the ones measured in this study. High densities of malaria-resistant mosquitoes would have to be maintained by continuous release from captive breeding facilities.</p

    Having Our Say: Examining Career Trajectories of Black Male Educators in P-12 Education

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    Achieving a diverse and inclusive workforce within P-12 education is critical to ensure that students receive a robust, quality educational experience. However, overcoming the shortage of educators of color has been a major dilemma for our nation's schools for decades. And, despite students of color comprising over 50% of current classroom populations and the United States Census Bureau's prediction that people of color will become the "majority-minority" in the overall United States population by 2043, these trends fail to correlate with representations of educators of color in P-12 education, especially for new cohorts of Black male teachers. In fact, according to the National Center for Education Statistics (NCES), male educators comprise only 23% of the public school workforce and, more troubling, Black male teachers represent less than 2% of the total teacher population

    What do we want to get out of this?:a critical interpretive synthesis of the value of process evaluations, with a practical planning framework

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    BACKGROUND: Process evaluations aim to understand how complex interventions bring about outcomes by examining intervention mechanisms, implementation, and context. While much attention has been paid to the methodology of process evaluations in health research, the value of process evaluations has received less critical attention. We aimed to unpack how value is conceptualised in process evaluations by identifying and critically analysing 1) how process evaluations may create value and 2) what kind of value they may create. METHODS: We systematically searched for and identified published literature on process evaluation, including guidance, opinion pieces, primary research, reviews, and discussion of methodological and practical issues. We conducted a critical interpretive synthesis and developed a practical planning framework. RESULTS: We identified and included 147 literature items. From these we determined three ways in which process evaluations may create value or negative consequences: 1) through the socio-technical processes of ‘doing’ the process evaluation, 2) through the features/qualities of process evaluation knowledge, and 3) through using process evaluation knowledge. We identified 15 value themes. We also found that value varies according to the characteristics of individual process evaluations, and is subjective and context dependent. CONCLUSION: The concept of value in process evaluations is complex and multi-faceted. Stakeholders in different contexts may have very different expectations of process evaluations and the value that can and should be obtained from them. We propose a planning framework to support an open and transparent process to plan and create value from process evaluations and negotiate trade-offs. This will support the development of joint solutions and, ultimately, generate more value from process evaluations to all. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12874-022-01767-7

    Reply: Cognitive behavioural therapy sessions approach ineffective for anxiety and depression in COPD: is the door closed for good?

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    Our trial does not support using a CBA approach to alleviate mild/moderate anxiety and/or depression in people with moderate/severe COPD. New approaches are needed to relieve the substantial mental health burden in these patients with complex needs. https://bit.ly/3TkkDt

    Supported self-management for people with type 2 diabetes:a meta-review of quantitative systematic reviews

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    OBJECTIVES: Self-management support aims to give people with chronic disease confidence to actively manage their disease, in partnership with their healthcare provider. A meta-review can inform policy-makers and healthcare managers about the effectiveness of self-management support strategies for people with type 2 diabetes, and which interventions work best and for whom. DESIGN: A meta-review of systematic reviews of randomised controlled trials (RCTs) was performed adapting Cochrane methodology. SETTING AND PARTICIPANTS: Eight databases were searched for systematic reviews of RCTs from January 1993 to October 2016, with a pre-publication update in April 2017. Forward citation was performed on included reviews in Institute for Scientific Information (ISI) Proceedings. We extracted data and assessed quality with the Revised-Assessment of Multiple Systematic Reviews (R-AMSTAR). PRIMARY AND SECONDARY OUTCOME MEASURES: Glycaemic control as measured by glycated haemoglobin (HbA1c) was the primary outcome. Body mass Index, lipid profiles, blood pressure and quality of life scoring were secondary outcomes. Meta-analyses reporting HbA1c were summarised in meta-forest plots; other outcomes were synthesised narratively. RESULTS: 41 systematic reviews incorporating data from 459 unique RCTs in diverse socio-economic and ethnic communities across 33 countries were included. R-AMSTAR quality score ranged from 20 to 42 (maximum 44). Apart from one outlier, the majority of reviews found an HbA1c improvement between 0.2% and 0.6% (2.2-6.5 mmol/mol) at 6 months post-intervention, but attenuated at 12 and 24 months. Impact on secondary outcomes was inconsistent and generally non-significant. Diverse self-management support strategies were employed; no single approach appeared optimally effective (or ineffective). Effective programmes tended to be multi-component and provide adequate contact time (>10 hours). Technology-facilitated self-management support showed a similar impact as traditional approaches (HbA1c MD -0.21% to -0.6%). CONCLUSIONS: Self-management interventions using a range of approaches improve short-term glycaemic control in people with type 2 diabetes including culturally diverse populations. These findings can inform researchers, policy-makers and healthcare professionals re-evaluating the provision of self-management support in routine care. Further research should consider implementation and sustainability.MC is supported by the Scottish School of Primary Care (academic fellowship in general practice)

    Fit for purpose : do we have the right tools to sustain NTD elimination?

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    Priorities for NTD control programmes will shift over the next 10-20 years as the elimination phase reaches the ‘end game’ for some NTDs, and the recognition that the control of other NTDs is much more problematic. The current goal of scaling up programmes based on preventive chemotherapy (PCT) will alter to sustaining NTD prevention, through sensitive surveillance and rapid response to resurgence. A new suite of tools and approaches will be required for both PCT and Intensive Disease Management (IDM) diseases in this timeframe to enable disease endemic countries to: 1. Sensitively and sustainably survey NTD transmission and prevalence in order to identify and respond quickly to resurgence. 2. Set relevant control targets based not only on epidemiological indicators but also entomological and ecological metrics and use decision support technology to help meet those targets. 3. Implement verified and cost-effective tools to prevent transmission throughout the elimination phase. Liverpool School of Tropical Medicine (LSTM) and partners propose to evaluate and implement existing tools from other disease systems as well as new tools in the pipeline in order to support endemic country ownership in NTD decision-making during the elimination phase and beyond
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