46 research outputs found

    Insecticidal activity of four medicinal plant extracts against Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)

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    Methanol extracts from four medicinal plants, Peganum harmala (Zygophyllaceae), Ajuga iva (Labiateae), Aristolochia baetica (Aristolochiaceae) and Raphanus raphanistrum (Brassicaceae) werestudied for their insecticidal effects on the stored grain pest Tribolium castaneum (Herbst). Response varied with plant species. Larvae growth was significantly inhibited when they were fed with extracts incorporated into the diet. Good insecticidal activity against T. castaneum larvae and adults wasachieved with extract of P. harmala seeds, followed by extract of A. iva, Ari. baetica and R. raphanistrum aerial parts. The extracts of the four plants disrupted the developmental cycle of the insect. Extracts of P. harmala, A. iva and Ari. baetica inhibited F1 progeny production. These naturally occurring plant extracts could be useful for managing populations of T. castaneu

    Einstien-Multidimensional Extrapolation methods

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    In this paper, we present a new framework for the recent multidimensional extrapolation methods: Tensor Global Minimal Polynomial (TG-MPE) and Tensor Global Reduced Rank Extrapolation (TG-RRE) methods. We develop a new approach to the one presented in \cite{17}. The proposed framework highlights, in addition their polynomial feature, the connection of TG-MPE and TG-RRE with nonlinear Krylov subspace methods. A unified algorithm is proposed for their implemention. Theoretical results are given and some numerical experiments on linear and nonlinear problems are considered to confirm the performance of the proposed algorithms

    A Method for Semidefinite Quasiconvex Maximization Problem

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    We introduce so-called semidefinite quasiconvex maximization problem. We derive new global optimality conditions by generalizing [9]. Using these conditions, we construct an algorithm which generates a sequence of local maximizers that converges to a global solution. Also, new applications of semidefinite quasiconvex maximization are given. Subproblems of the proposed algorithm are semidefinite linear programming

    Research collaboration in Tehran University of Medical Sciences: two decades after integration

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    Background: In 1985 medical schools were integrated into the Ministry of Health, and the Ministry of Health and Medical Education was created in Iran. Under this infrastructure education, research and service provision are unified, and it is expected that collaboration between researchers and decision makers become easier in such an integrated context. The question here is how the researchers behavior in the biggest medical university of the country towards collaboration is, i.e. how much do decision makers participate in different stages of research? Which factors affect it? Methodology: The samples under study were all Tehran University of Medical Sciences (TUMS) completed research projects that had gotten grants in 2004 and were over by the time this study was done. Two questionnaires were designed for this study: i) the research checklist which was filled for 301 projects, ii) the researcher's questionnaire, which was sent to principle investigators, 208 of which were collected. Multiple linear regression analysis was used for evaluating the potential factors affecting individuals 'collaboration score'. Results: Only 2.2 percent of TUMS' projects initiated in 2004 have had collaboration as a joint PI or co-investigator from non-academic organizations. The principle investigators mean collaboration score was 2.09, where 6 was the total score. So the collaboration score obtained was 35%. The 'type of research' had significant association with the collaboration score which is shown in the linear regression; collaboration was seen more in clinical (p = 0.007) and health system researches (p = 0.001) as compared to basic research. Conclusion: The present study shows that not many individuals collaborated as co-investigators from outside the university. This finding shows that research policy makers need to introduce interventions in this field. And assessment of barriers to collaboration and its facilitating factors should be considered in order to make it actually happen. © 2009 Majdzadeh et al; licensee BioMed Central Ltd

    The clinical effectiveness of individual behaviour change interventions to reduce risky sexual behaviour after a negative human immunodeficiency virus test in men who have sex with men: systematic and realist reviews and intervention development

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    Background: Men who have sex with men (MSM) experience significant inequalities in health and well-being. They are the group in the UK at the highest risk of acquiring a human immunodeficiency virus (HIV) infection. Guidance relating to both HIV infection prevention, in general, and individual-level behaviour change interventions, in particular, is very limited. Objectives: To conduct an evidence synthesis of the clinical effectiveness of behaviour change interventions to reduce risky sexual behaviour among MSM after a negative HIV infection test. To identify effective components within interventions in reducing HIV risk-related behaviours and develop a candidate intervention. To host expert events addressing the implementation and optimisation of a candidate intervention. Data sources: All major electronic databases (British Education Index, BioMed Central, Cumulative Index to Nursing and Allied Health Literature, EMBASE, Educational Resource Index and Abstracts, Health and Medical Complete, MEDLINE, PsycARTICLES, PsycINFO, PubMed and Social Science Citation Index) were searched between January 2000 and December 2014. Review methods: A systematic review of the clinical effectiveness of individual behaviour change interventions was conducted. Interventions were examined using the behaviour change technique (BCT) taxonomy, theory coding assessment, mode of delivery and proximity to HIV infection testing. Data were summarised in narrative review and, when appropriate, meta-analysis was carried out. Supplemental analyses for the development of the candidate intervention focused on post hoc realist review method, the assessment of the sequential delivery and content of intervention components, and the social and historical context of primary studies. Expert panels reviewed the candidate intervention for issues of implementation and optimisation. Results: Overall, trials included in this review (n = 10) demonstrated that individual-level behaviour change interventions are effective in reducing key HIV infection risk-related behaviours. However, there was considerable clinical and methodological heterogeneity among the trials. Exploratory meta-analysis showed a statistically significant reduction in behaviours associated with high risk of HIV transmission (risk ratio 0.75, 95% confidence interval 0.62 to 0.91). Additional stratified analyses suggested that effectiveness may be enhanced through face-to-face contact immediately after testing, and that theory-based content and BCTs drawn from ‘goals and planning’ and ‘identity’ groups are important. All evidence collated in the review was synthesised to develop a candidate intervention. Experts highlighted overall acceptability of the intervention and outlined key ways that the candidate intervention could be optimised to enhance UK implementation. Limitations: There was a limited number of primary studies. All were from outside the UK and were subject to considerable clinical, methodological and statistical heterogeneity. The findings of the meta-analysis must therefore be treated with caution. The lack of detailed intervention manuals limited the assessment of intervention content, delivery and fidelity. Conclusions: Evidence regarding the effectiveness of behaviour change interventions suggests that they are effective in changing behaviour associated with HIV transmission. Exploratory stratified meta-analyses suggested that interventions should be delivered face to face and immediately after testing. There are uncertainties around the generalisability of these findings to the UK setting. However, UK experts found the intervention acceptable and provided ways of optimising the candidate intervention. Future work: There is a need for well-designed, UK-based trials of individual behaviour change interventions that clearly articulate intervention content and demonstrate intervention fidelity

    Multi-level analysis of electronic health record adoption by health care professionals: A study protocol

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    <p>Abstract</p> <p>Background</p> <p>The electronic health record (EHR) is an important application of information and communication technologies to the healthcare sector. EHR implementation is expected to produce benefits for patients, professionals, organisations, and the population as a whole. These benefits cannot be achieved without the adoption of EHR by healthcare professionals. Nevertheless, the influence of individual and organisational factors in determining EHR adoption is still unclear. This study aims to assess the unique contribution of individual and organisational factors on EHR adoption in healthcare settings, as well as possible interrelations between these factors.</p> <p>Methods</p> <p>A prospective study will be conducted. A stratified random sampling method will be used to select 50 healthcare organisations in the Quebec City Health Region (Canada). At the individual level, a sample of 15 to 30 health professionals will be chosen within each organisation depending on its size. A semi-structured questionnaire will be administered to two key informants in each organisation to collect organisational data. A composite adoption score of EHR adoption will be developed based on a Delphi process and will be used as the outcome variable. Twelve to eighteen months after the first contact, depending on the pace of EHR implementation, key informants and clinicians will be contacted once again to monitor the evolution of EHR adoption. A multilevel regression model will be applied to identify the organisational and individual determinants of EHR adoption in clinical settings. Alternative analytical models would be applied if necessary.</p> <p>Results</p> <p>The study will assess the contribution of organisational and individual factors, as well as their interactions, to the implementation of EHR in clinical settings.</p> <p>Conclusions</p> <p>These results will be very relevant for decision makers and managers who are facing the challenge of implementing EHR in the healthcare system. In addition, this research constitutes a major contribution to the field of knowledge transfer and implementation science.</p
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