13,214 research outputs found

    A closer look at multiple-clone Plasmodium vivax infections: detection methods, prevalence and consequences

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    The naturally occurring clonal diversity among field isolates of the major human malaria parasite Plasmodium vivax remained unexplored until the early 1990s, when improved molecular methods allowed the use of blood samples obtained directly from patients, without prior in vitro culture, for genotyping purposes. Here we briefly review the molecular strategies currently used to detect genetically distinct clones in patient-derived P. vivax samples, present evidence that multiple-clone P. vivax infections are commonly detected in areas with different levels of malaria transmission and discuss possible evolutionary and epidemiological consequences of the competition between genetically distinct clones in natural human infections. We suggest that, when two or more genetically distinct clones are present in the same host, intra-host competition for limited resources may select for P. vivax traits that represent major public health challenges, such as increased virulence, increased transmissibility and antimalarial drug resistance.CNPqMount Sinai School of Medicin

    Quantificando os efeitos do aquecimento global e das condições socioeconômicas locais na transmissão de malária

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    OBJETIVO: Apresenta-se um modelo matemático mostrando como esse instrumento pode ser importante para descrever a transmissão de malária. MÉTODOS: Baseado no modelo proposto previamente, foram quantificados os efeitos de dois fatores que podem afetar a transmissão da malaria: a temperatura ambiente e as condições socioeconômicas locais. RESULTADOS/CONCLUSÕES: A quantificação foi feita estudando o modelo proposto no estado estacionário e na sua dinâmica. Dependendo do nível de risco de malária, os principais efeitos na transmissão de malária são devidos à temperatura ambiente ou às condições socioeconômicas.OBJECTIVE: To show how a mathematical model can be used to describe and to understand the malaria transmission. METHODS: The effects on malaria transmission due to the impact of the global temperature changes and prevailing social and economic conditions in a community were assessed based on a previously presented compartmental model, which describes the overall transmission of malaria. RESULTS/CONCLUSIONS: The assessments were made from the scenarios produced by the model both in steady state and dynamic analyses. Depending on the risk level of malaria, the effects on malaria transmission can be predicted by the temperature ambient or local social and-economic conditions

    Assessing The Effects Of Global Warming And Local Social And Economic Conditions On The Malaria Transmission.

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    To show how a mathematical model can be used to describe and to understand the malaria transmission. The effects on malaria transmission due to the impact of the global temperature changes and prevailing social and economic conditions in a community were assessed based on a previously presented compartmental model, which describes the overall transmission of malaria. The assessments were made from the scenarios produced by the model both in steady state and dynamic analyses. Depending on the risk level of malaria, the effects on malaria transmission can be predicted by the temperature ambient or local social and-economic conditions.34214-2

    Uncovering dimensions of the impact of blockchain technology in supply chain management

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    Supply chains around the globe are faced with difficulties and disruptions due to the worldwide pandemic situation and digital solutions are needed. There is significant research interest in the implementation of blockchain technology (BCT) for supply chain management (SCM). A challenge that remains is analyzing the interactions of BCT in different areas of SCM. This study aims to identify the influential dimensions of the impact of BCT adoption in SCM and to discuss the synergetic and counter-synergetic effects between these dimensions. Advantages, disadvantages, and constraints of adopting BCT in the SCM context are explored through a systematic literature review, which provides the foundation for identifying the dimensions of impact. The interactions between these dimensions are conceptually discussed. This study introduces three dimensions of the impact of implementing BCT in SCM: ‘operations and processes’, ‘supply chain relationships’, and ‘innovation and data access’. These dimensions are interrelated and have overlapping areas within them, which leads to synergetic and counter-synergetic effects. The overlaps and synergies of the three dimensions of impact are illustrated, and the virtuous and vicious cycles of BCT adoption in SCM cases are highlighted. This study assists scholars and practitioners by clarifying the synergetic relationships within the dimensions of the impact of BCT in SCM and by providing considerations to prevent undesirable effects and expand desired ones.info:eu-repo/semantics/publishedVersio

    Use of blockchain technology to manage the supply chains: Comparison of perspectives between technology providers and early industry adopters

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    Following the interest in blockchain technology (BCT) business solutions and the nascent stage of technology in supply chain (SC) practices, this research compares views from business practitioners who are experienced in real cases of BCT adoption with the views of technology consultants proficient in the complexities of BCT to analyze the benefits and challenges BCT holds for SCs. Based on the comparison of the two sides, the joint views that both adopters and technology consultants share is the ability that BCT holds to speed up processes across SCs through decentralized data access, thus decreasing human errors and reducing paperwork. However, technology consultants perceive the need to increase BCT awareness levels of businesses, to prevent BCT implementation just for reasons such as ‘recordkeeping’ and to reduce misconceptions in areas such as cryptocurrency applications. The findings also revealed that technology consultants insist on the careful evaluation and definition of records to be kept on BCT platforms prior to the adoption process, in order to avoid unnecessary data input. Currently, according to early industry adopters’ cases, most business attempts of BCT adoption use private networks, so technology consultants promote business entities on developing plans towards open-access public networks.info:eu-repo/semantics/publishedVersio

    Magnetic Resonance Image In The Diagnosis And Evaluation Of Extra-prostatic Extension And Involvement Of Seminal Vesicles Of Prostate Cancer: A Systematic Review Of Literature And Meta-analysis.

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    Systematic review of literature and meta-analysis to evaluate the results of magnetic resonance image 1.5T with endorectal coil in the diagnosis and evaluation of extra-prostatic extension and involvement of seminal vesicles of prostate cancer, compared to the histopathological results of the radical prostatectomy specimen. It was conducted a systematic review of literature and meta-analyses of all studies data published after 2008. In those studies, the patients with prostate cancer with indication to radical prostatectomy were submitted to magnetic resonance image (MRI) at pre-operatory period and the results were compared to those of histopathological studies after the surgery. The selected terms for research included prostate cancer, magnetic resonance, radical prostatectomy, and prostate cancer diagnosis, in the databases EMBASE, LILACS, PUBMED/MEDLINE and Cochrane Library. The data were collected using a specific qualitative instrument and the meta-analysis data were presented in the forest plot graphics, homogeneity test and sROC curves and funnel plot. A total of seven studies were included, with a total of 603 patients. Among these studies, six evaluated the value of MRI for the detection of prostate cancer, and the median sensitivity of meta-analysis was 0.6 and specificity 0.58, but with heterogeneity among the studies. Three studies evaluated extra-prostatic extension with a median sensitivity of 0.49, specificity 0.82 and heterogeneity only for sensitivity. Three studies evaluated invasion of seminal vesicles, with median sensitivity of 0.45 and specificity 0.96, with heterogeneity in both analysis. Magnetic resonance of 1.5T with endocoil showed low values of sensitivity and specificity for the diagnosis and staging of prostate cancer. The reviewed studies showed a significant heterogeneity among them. The best observed result was MRI specificity for invasion of seminal vesicles. More studies are necessary to evaluate new techniques and parameters before recommending the routine use of MRI in clinical practice.39215516
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