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The objective of this study was to investigate the bacterial adhesion under different wall shear stresses in turbulent flow and using a diverse bacterial consortium. A better understanding of the mechanisms governing microbial adhesion can be useful in diverse domains such as industrial processes, medical fields or environmental biotechnologies. The impact of wall shear stress-four values ranging from 0.09 to 7.3 Pa on polypropylene (PP) and polyvinyl chloride (PVC)-was carried out in rotating annular reactors to evaluate the adhesion in terms of morphological and microbiological structures. A diverse inoculum consisting of activated sludge was used. Epifluorescence microscopy was used to quantitatively and qualitatively characterize the adhesion. Attached bacterial communities were assessed by molecular fingerprinting profiles (CE-SSCP). It has been demonstrated that wall shear stress had a strong impact on both quantitative and qualitative aspects of the bacterial adhesion. ANOVA tests also demonstrated the significant impact of wall shear stress on all three tested morphological parameters (surface coverage, number of objects and size of objects) (p-values < 2.10-16). High wall shear stresses increased the quantity of attached bacteria but also altered their spatial distribution on the substratum surface. As the shear increased, aggregates or clusters appeared and their size grew when increasing the shears. Concerning the microbiological composition, the adhered bacterial communities changed gradually with the applied shear.

BackgroundThe increasing incidence and heterogeneous behavior of intestinal neuroendocrine tumors (iNETs) pose a clinicopathological challenge. Our goal was to decribe the prognostic value of the new WHO 2010 grading and the AJCC/UICC TNM staging systems for iNETs. Moreover, outcomes of patients treated with somatostatin analogs were assessed.MethodsWe collected epidemiological and clinicopathological data from 93 patients with histologically proven iNETs including progression and survival outcomes. The WHO 2010 grading and the AJCC/UICC TNM staging systems were applied for all cases. RECIST criteria were used to define progression. Kaplan-Meier analyses for progression free survival (PFS) and overall survival (OS) were performed.ResultsMean follow-up was 58.6 months (4-213 months). WHO 2010 grading yielded PFS and disease-specific OS of 125.0 and 165.8 months for grade 1 (G1), 100.0 and 144.2 months for G2 and 15.0 and 15.8 months for G3 tumors (p = 0.004 and p = 0.001). Using AJCC staging, patients with stage I and II tumors had no progression and no deaths. Stage III and IV patients demonstrated PFS of 138.4 and 84.7 months (p = 0.003) and disease-specific OS of 210.0 and 112.8 months (p = 0.017). AJCC staging also provided informative PFS (91.2 vs. 50.0 months, p = 0.004) and OS (112.3 vs. 80.0 months, p = 0.005) measures with somatostatin analog use in stage IV patients.ConclusionOur findings underscore the complementarity of WHO 2010 and AJCC classifications in providing better estimates of iNETS disease outcomes and extend the evidence for somatostatin analog benefit in patients with metastatic disease.

This article offers a cross study of the relationship to knowledge regarding the natural sciences and the humanities and social sciences, from the point of view of secondary school students in Quebec. It is an extension of studies in science education and humanities which tends to strengthen civic engagement and the teaching and learning of socio-controversial issues at the secondary level, in order to enhance various facets of the relationship to knowledge and to the act of learning of young people. Several studies have analyzed the relationship to knowledge of students about natural sciences. However, very little research has attempted to characterize the relationship to knowledge toward humanities and social sciences then to draw distinctions with respect to relationship to knowledge in the natural sciences. This study aims to analyze the relationship to knowledge about each of the two areas and then identify possible links between them. To do this, we appeal to a conceptualization incorporating the viewpoints of two contrasting disciplinary fields, within epistemic, identity and social dimensions of the concept of relationship to knowledge. In terms of method, two data collection instruments are mobilized: a questionnaire name "bilan de savoirs" and the semi-structured interview. The sample includes 41 secondary V students of Quebec state, who responded to the questionnaire. After, 10 students participated to the interviews in order to deepen the answers given previously and address new aspects. The results allow to draw parallels but also distinctions between the relationship to knowledge in respect of the natural sciences and humanities and social sciences. Finally, the results lead us to formulate proposals for teacher education in which the practice of interdisciplinarity in secondary schools is encouraged.

To cope with complex environmental issues that have a direct impact on cultural and natural environments, education for empowerment seems to be an unavoidable avenue (Schreiner, Henriksen & Kirkeby Hansen, 2005). However, to allow transformations in terms of educational discourses and practices, it seems necessary to clarify and define the limits of the conceptual tools identified as relevant by researchers in the field (Stevenson, Brody, Dillon & Wals, 2013). In this article, inspired be the theoretical frame of a doctoral research in progress, the concepts of empowerment, agency and self-efficacy beliefs will be further explored. They will then be connected to highlight the concept of sense of empowerment for a transformative and critical environmental education.