111 research outputs found

    Compréhension du fonctionnement de l'appel à la peur et du role médiateur de la réactance situationnelle en communication préventive de l'anorexie

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    Anorexia prevention or more widely disorder eating behavior, has a strong social and societal interest. It also presents an academic interest, since this context is under-represented in research. Existing anorexia prevention campaigns use the strategy of fear appeal, despite a non-consensual literature on the level of fear appeal to adopt and the exact functioning of the mechanism. The existing literature also suggests, to explain failure of fear appeal, that there is a situational reactance, even though this has never been validated. Four experiments on young women students, public particularly sensitive to this context, allow us to understand and validate the mechanism of fear appeal in successive mediations and while integrating situational reactance. Through these experiments, it is shown that the message with fear appeal creates a cognitive and emotional state of fear, and perceived severity that will oppositely influence situational reactance. The latter influences the perceived efficacy of recommendation, which in turn determines the success or failure of the message. In parallel, the mediator, but secondary role, of self-efficacy on the perceived efficacy of the recommendation is revealed, as well as the moderator of perceived susceptibility. Furthermore, each study attempts to handle, in addition to the level of fear appeal, various components and characteristics of the message, whose effects on the fear appeal mechanism solve in part, some existing conflicts in the literature. Thus, the role of the components, visual and verbal, on the level of fear felt is examined (studies 1 and 2). The effect of the wording of the recommendation (study 2), as well as the effect of the type of argument (study 3) on the process of fear appeal are analyzed. Finally, the addition of the disgust on fear appeal and the validation process by a behavioral measure yet refine understanding the mechanism of fear appeal (study 4). To conclude, the key preventive effective communication with anorexia use of fear appeals are given and results are discussed and complemented with possible future research directions, some of which are used to overcome the limitations mentioned on this research.A prévention de l'anorexie, et plus largement des troubles de comportement alimentaire, revêt un intérêt social et sociétal fort. Elle comporte également un intérêt académique, ce contexte étant sous-représenté en recherche. Les communications existantes sur la prévention de l'anorexie utilisent la stratégie de l'appel à la peur, malgré une littérature non consensuelle sur le niveau d'appel à adopter et sur le fonctionnement exact du mécanisme. La littérature propose également, pour expliquer l'échec de l'appel à la peur, l'existence d'une réactance situationnelle, sans que celle-ci n'ait jamais été validée. Quatre expérimentations auprès de jeunes femmes étudiantes, public particulièrement sensible dans ce contexte, permettent de comprendre et valider le fonctionnement de l'appel à la peur par médiations successives et en intégrant la réactance situationnelle. Il est montré que le message avec appel à la peur crée un état cognitivo-émotionnel composé de peur et de sévérité perçue qui vont influer de manière opposée sur la réactance situationnelle. Cette dernière influence à son tour la perception d'efficacité de la recommandation, qui déterminera ensuite le succès ou l'échec du message. En parallèle, le rôle médiateur, mais secondaire, de l'auto-efficacité sur l'efficacité perçue de la recommandation est révélé, de même que celui modérateur de la vulnérabilité perçue. En complément de ce résultat, chacune des études s'attache à manipuler, en plus du niveau d'appel à la peur, différentes composantes et caractéristiques du message, dont les effets sur le mécanisme d'appel à la peur permettent de résoudre, en partie, certains conflits existants dans la littérature. Ainsi, le rôle des composantes, visuelle et verbale, sur le niveau ressenti de peur est examiné (études 1 et 2). L'effet de la formulation de la recommandation (étude 2), de même que l'effet du type d'argument (étude 3) sur le processus de l'appel à la peur sont analysés. Enfin, l'ajout du dégoût à l'appel à la peur et la validation du fonctionnement du processus par une mesure comportementale affinent encore la compréhension des mécanismes d'action de l'appel à la peur (étude 4). Pour conclure, les clés d'une communication préventive de l'anorexie efficace avec recours à l'appel à la peur sont données et les résultats discutés et complétés par des voies de recherche possibles, dont certaines permettent de pallier les limites mentionnées pour la présente recherche

    Perspectivas y experiencias en el empleo de tecnologias no convencionales en el tratamiento de residuales liquidos

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    Parte de los residuales que genera la industria y la actividad social son corrientes acuosas, que pueden contener compuestos tóxicos y poco biodegradables, donde el tratamiento biológico analiza la importancia de las técnicas no convencionales en el tratamiento de residuales y la descontaminación de aguas. Entre los procesos novedosos se encuentran el ultrasonido, la oxidación catalítica y los reactores con biomembranas. El ultrasonido se emplea en la degradación de compuestos refractarios que no pueden ser tratados por métodos biológicos, en mejorar la degradación biológica y en la desintegración de lodos. La oxidación catalítica es más prometedora desde el punto de vista económico, para el tratamiento de aguas residuales con contaminantes persistentes. El empleo del carbón activado como catalizador en el tratamiento de residuales por oxidación catalítica abre un camino importante en el uso extensivo de este proceso. Los biorreactores de membranas ofrecen un grupo de ventajas relacionadas con la calidad y su reutilización, la reducción de lodos, la estabilidad del permeado con independencia de picos de carga y menores requerimientos de espacio. Estas tecnologías pueden emplearse combinadas entre sí o con los procesos convencionales. La elección del esquema de tratamiento dependerá de las características del residual a tratar o del agua a recuperar, de los volúmenes y de los requisitos que se establezcan para el agua tratada

    Application of sludge-based carbonaceous materials in a hybrid water treatment process based on adsorption and catalytic wet air oxidation

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    This paper describes a preliminary evaluation of the performance of carbonaceous materials prepared from sewage sludges (SBCMs) in a hybrid water treatment process based on adsorption and catalytic wet air oxidation; phenol was used as the model pollutant. Three different sewage sludges were treated by either carbonisation or steam activation, and the physico-chemical properties of the resultant carbonaceous materials (e.g. hardness, BET surface area, ash and elemental content, surface chemistry) were evaluated and compared with a commercial reference activated carbon (PICA F22). The adsorption capacity for phenol of the SBCMs was greater than suggested by their BET surface area, but less than F22; a steam activated, dewatered raw sludge (SA_DRAW) had the greatest adsorption capacity of the SBCMs in the investigated range of concentrations (<0.05 mol L−1). In batch oxidation tests, the SBCMs demonstrated catalytic behaviour arising from their substrate adsorptivity and metal content. Recycling of SA_DRAW in successive oxidations led to significant structural attrition and a hardened SA_DRAW was evaluated, but found to be unsatisfactory during the oxidation step. In a combined adsorption–oxidation sequence, both the PICA carbon and a selected SBCM showed deterioration in phenol adsorption after oxidative regeneration, but a steady state performance was reached after 2 or 3 cycles

    High-Resolution 1.5-Tesla Magnetic Resonance Imaging for Tissue-Engineered Constructs: A Noninvasive Tool to Assess Three-Dimensional Scaffold Architecture and Cell Seeding

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    International audienceTissue-engineered scaffolds are made of biocompatible polymers with various structures, allowing cell seeding, growth, and differentiation. Noninvasive imaging methods are needed to study tissue-engineered constructs before and after implantation. Here, we show that high-resolution magnetic resonance imaging (MRI) performed on a clinical 1.5-T device is a reliable technique to assess three-dimensional structures of porous scaffolds and to validate cell-seeding procedures. A high-temperature superconducting detection coil was used to achieve a resolution of 30Â30Â30 mm 3 when imaging the scaffolds. Three types of structures with tuneable architectures were prepared from naturally derived polysaccharides and evaluated as scaffolds for mesenchymal stem cell (MSC) culture. To monitor cell seeding, MSCs were magnetically labeled using simple incubation with anionic citrate-coated iron-oxide nanoparticles for 30 min. Iron uptake was quantified using single-cell magnetophoresis, and cell proliferation was checked for 7 days after labeling. Three-dimensional (3D) microstructures of scaffolds were assessed using MRI, revealing lamellar or globular porous organization according to the scaffold preparation process. MSCs with different iron load (5, 12 and 31 pg of iron per cell) were seeded on scaffolds at low density (132 cells=mm 3) and detected on 3D gradient-echo MR images according to phase distortions and areas of intensely low signal, whose size increased with cell iron load and echo time. Overall signal loss in the scaffold correlated with the number of seeded cells and their iron load. Different organizations of cells were observed depending on the scaffold architecture. After subcutaneous implantation in mice, scaffolds seeded with labeled cells could be distinguished in vivo from scaffold with nonlabeled cells by observation of signal and phase heterogeneities and by measuring the global signal loss. High-resolution 1.5-T MRI combined with efficient intracellular contrast agents shows promise for noninvasive 3D visualization of tissue-engineered constructs before and after in vivo implantation

    Role of the urinary concentrating process in the renal effects of high protein intake

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    Role of the urinary concentrating process in the renal effects of high protein intake. High protein diet is known to increase glomerular filtration rate (GFR) and induce kidney hypertrophy. The mechanisms underlying these changes are not understood. Since the mammalian kidney comprises different nephron segments located in well-delineated zones, it is conceivable that the hypertrophy does not affect all kidney zones and all nephron segments uniformly. The present experiments were designed to study the chronic effects of high or low isocaloric protein diets (HP = 32% or LP = 10% casein, respectively) on kidney function and morphology in Sprague-Dawley rats. HP diet induced significant increases in kidney mass, GFR, free water clearance, and maximum urine concentrating ability. Kidney hypertrophy was characterized by: 1. a preferential increase in thickness of the inner stripe of the outer medulla (IS) (+ 54%, P < 0.001, while total kidney height, from cortex to papillary tip, increased only by 18%); 2. a marked hypertrophy of the thick ascending limbs (TAL) in the inner stripe (+40% epithelium volume/unit tubular length, P < 0.05) but not in the outer stripe nor in the cortex; 3. an increase in heterogeneity of glomeruli between superficial (S) and deep (D) nephrons (D/S = 1.47 in HP vs. 1.17 in LP, P < 0.05). In contrast, normal kidney growth with age and kidney hypertrophy induced by uninephrectomy were not accompanied by preferential enlargement of IS structures. The morphologic changes induced by high protein intake parallel those we previously reported in rats fed a normal diet (25% protein) but in which the operation of the urine concentrating mechanism was chronically stimulated by ADH infusion or by reduction in water intake. This similarity and the dramatic increase in free water reabsorption induced by HP diet suggest that high protein intake affects kidney function and morphology by increasing the level of operation of the urine concentrating process. The preferential increase in TAL epithelium disclosed in this study, and the recent demonstration by others of a decreased salt concentration in the early distal tubule of HP rats raises the possibility that the protein-induced increase in GFR is mediated by a depression of tubuloglomerular feedback resulting from an increased salt transport in the medullary TAL in relation with an increase in free water generation

    X-ray magnetic circular dichroïsm provides strong evidence for tetrahedral iron in ferrihydrite

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    International audience[1] Ferrihydrite is an important iron oxyhydroxide for earth and environmental sciences, biology, and technology. Nevertheless, its mineral structure remains a matter of debate. The stumbling block is whether a significant amount of tetrahedrally coordinated iron is present. Here we present the first X-ray magnetic circular dichroïsm (XMCD) measurements performed on a well characterized synthetic sample of 6-line fer-rihydrite, at both K and L 2,3 energy edges of iron. XMCD results demonstrate unambiguously the presence of tetrahedrally coordinated Fe(III) in the mineral structure, in quantities compatible with the latest extended X-ray absorption fine structure (EXAFS) analyses suggesting a concentration of 20–30%. Moreover , we find an antiferromagnetic coupling between tetrahedral and octahedral sublattices, with the octa-hedral sublattice parallel to the external magnetic field. Components: 5100 words, 3 figures

    The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on fermented foods

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    An expert panel was convened in September 2019 by The International Scientific Association for Probiotics and Prebiotics (ISAPP) to develop a definition for fermented foods and to describe their role in the human diet. Although these foods have been consumed for thousands of years, they are receiving increased attention among biologists, nutritionists, technologists, clinicians and consumers. Despite this interest, inconsistencies related to the use of the term ‘fermented’ led the panel to define fermented foods and beverages as “foods made through desired microbial growth and enzymatic conversions of food components”. This definition, encompassing the many varieties of fermented foods, is intended to clarify what is (and is not) a fermented food. The distinction between fermented foods and probiotics is further clarified. The panel also addressed the current state of knowledge on the safety, risks and health benefits, including an assessment of the nutritional attributes and a mechanistic rationale for how fermented foods could improve gastrointestinal and general health. The latest advancements in our understanding of the microbial ecology and systems biology of these foods were discussed. Finally, the panel reviewed how fermented foods are regulated and discussed efforts to include them as a separate category in national dietary guidelines

    The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on fermented foods

    Get PDF
    An expert panel was convened in September 2019 by The International Scientific Association for Probiotics and Prebiotics (ISAPP) to develop a definition for fermented foods and to describe their role in the human diet. Although these foods have been consumed for thousands of years, they are receiving increased attention among biologists, nutritionists, technologists, clinicians and consumers. Despite this interest, inconsistencies related to the use of the term ‘fermented’ led the panel to define fermented foods and beverages as “foods made through desired microbial growth and enzymatic conversions of food components”. This definition, encompassing the many varieties of fermented foods, is intended to clarify what is (and is not) a fermented food. The distinction between fermented foods and probiotics is further clarified. The panel also addressed the current state of knowledge on the safety, risks and health benefits, including an assessment of the nutritional attributes and a mechanistic rationale for how fermented foods could improve gastrointestinal and general health. The latest advancements in our understanding of the microbial ecology and systems biology of these foods were discussed. Finally, the panel reviewed how fermented foods are regulated and discussed efforts to include them as a separate category in national dietary guidelines

    Neuroendocrine Differentiation in Conventional Colorectal Adenocarcinomas: Incidental Finding or Prognostic Biomarker?

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    Background Colorectal mixed adenoneuroendocrine carcinomas (MANECs) are clinically highly aggressive neoplasms. MANECs are composed of variable adenocarcinoma components combined with morphologically distinct neuroendocrine carcinoma components, which are confirmed by synaptophysin immunohistochemistry, the gold standard marker of a neuroendocrine differentiation. However, the biological behavior of adenocarcinomas that express synaptophysin but do not show a typical neuroendocrine morphology remains unclear. Methods We investigated synaptophysin expression in 1002 conventional colorectal adenocarcinomas and correlated the results with clinicopathological characteristics and patient survival and compared the survival characteristics of synaptophysin expression groups to MANECs. Results Synaptophysin expression in conventional colorectal adenocarcinomas was associated with a shortened disease-free survival (p = 0.037), but not with overall survival or disease-specific survival (DSS) in univariate analyses and without any survival impact in multivariate analyses. Patients with "true" MANECs, on the other hand, showed a significantly shorter survival than all conventional adenocarcinomas with or without synaptophysin expression in uni- and multivariate analyses (e.g., multivariate DSS: p < 0.001, HR: 5.20). Conclusions Our study demonstrates that synaptophysin expression in conventional colorectal adenocarcinomas, in contrast to MANECs, is not associated with a significantly poorer clinical outcome when compared to adenocarcinomas without synaptophysin expression. Furthermore, our data suggest that conventional adenocarcinomas with a diffuse synaptophysin expression should not be classified as MANECs, also strongly arguing that synaptophysin testing should be reserved for carcinomas with an H&E morphology suggestive of a neuroendocrine differentiation.Simple Summary Colorectal MANECs are highly aggressive carcinomas defined by a distinct neuroendocrine morphology and positivity for synaptophysin in the neuroendocrine component. It is unclear whether a neuroendocrine differentiation in conventional adenocarcinomas without a suggestive morphology is of clinical relevance. We tested 1002 conventional colorectal carcinomas with a non-neuroendocrine morphology for synaptophysin expression and correlated the results with clinicopathological characteristics as well as patient survival and compared the survival characteristics of synaptophysin expression groups to those of true MANECs. We found no survival differences between synaptophysin expression groups within conventional colorectal adenocarcinomas. MANECs, on the other hand, showed significantly worse survival characteristics. Our data suggest that synaptophysin expression in conventional colorectal adenocarcinomas is of minor prognostic relevance and that conventional adenocarcinomas with a diffuse synaptophysin expression should not be classified as MANECs. Abstract Background: Colorectal mixed adenoneuroendocrine carcinomas (MANECs) are clinically highly aggressive neoplasms. MANECs are composed of variable adenocarcinoma components combined with morphologically distinct neuroendocrine carcinoma components, which are confirmed by synaptophysin immunohistochemistry, the gold standard marker of a neuroendocrine differentiation. However, the biological behavior of adenocarcinomas that express synaptophysin but do not show a typical neuroendocrine morphology remains unclear. Methods: We investigated synaptophysin expression in 1002 conventional colorectal adenocarcinomas and correlated the results with clinicopathological characteristics and patient survival and compared the survival characteristics of synaptophysin expression groups to MANECs. Results: Synaptophysin expression in conventional colorectal adenocarcinomas was associated with a shortened disease-free survival (p = 0.037), but not with overall survival or disease-specific survival (DSS) in univariate analyses and without any survival impact in multivariate analyses. Patients with “true” MANECs, on the other hand, showed a significantly shorter survival than all conventional adenocarcinomas with or without synaptophysin expression in uni- and multivariate analyses (e.g., multivariate DSS: p < 0.001, HR: 5.20). Conclusions: Our study demonstrates that synaptophysin expression in conventional colorectal adenocarcinomas, in contrast to MANECs, is not associated with a significantly poorer clinical outcome when compared to adenocarcinomas without synaptophysin expression. Furthermore, our data suggest that conventional adenocarcinomas with a diffuse synaptophysin expression should not be classified as MANECs, also strongly arguing that synaptophysin testing should be reserved for carcinomas with an H&E morphology suggestive of a neuroendocrine differentiation
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