282 research outputs found

    Film Thickness and Friction Relationship in Grease Lubricated Rough Contacts

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    The relationship between the film generation and the coefficient of friction in grease lubricated contacts was investigated. Ball-on-disc tests were performed under different operating conditions: entrainment speed, lubricant temperature and surface roughness. The tests were performed with fully formulated greases and their base oils. The greases were formulated with different thickener types and also different base oils natures and viscosities. Film thickness measurements were performed in ball-on-glass disc tests, and Stribeck curves were measured in ball-on-steel disc tests with discs of different roughness. The role of the thickener and the base oil nature/viscosity on the film thickness and coefficient of friction was addressed and the greases’ performance was compared based on their formulation.info:eu-repo/semantics/publishedVersio

    Corrosion resistance in artificial perspiration of Cr-based decorative coatings

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    We aim at developing hexavalent chromium-free coatings for frequently touched decorative parts. Cr(N,O) and multilayered CrN/CrO coatings were deposited by means of reactive magnetron sputtering. All samples presented good adhesion to the substrates enhanced by an epoxy layer designed to enhance PVD coating adhesion. Similar substrates are found in the automotive industry and can be used in appliances where a metallic finish is desired by the consumer. Corrosion behavior was induced, using artificial sweat to simulate long exposure to human touch for 96 h. In potentiodynamic polarization tests, the coatings were revealed to be nobler than the substrate alone. Cr displayed a non-existent passivation region, while gCrN exhibited a quick passivation of the surface and its respective breakdown and several current fluctuations, indicating the occurrence of pitting, which was confirmed by SEM micrography after the corrosion. Regarding EIS results, all films depicted a diminution of impedance modulus (|Z|) after 96 h, which indicates a diminution of corrosion resistance against artificial sweat. Nitride films exhibited the worst anticorrosive features. On the other hand, Cr and CrO exhibited the highest |Z| values. These results are corroborated by low the corrosion rates of both coatings. The equivalent electrical circuit allows us to confirm oxide formation in the outermost layer of the films due to electrolyte/surface interaction, indicating a self-protecting mechanism. Nitride films showed the lowest values and less corrosion resistance, confirming the results obtained in polarization potentiodynamic tests. The coatings developed in this work, namely Cr and CrO, showed a promising corrosion resistance behavior that could endure a lifetime of frequent human touch in various decorative applications either automotive or general appliances.This work was supported by COMPETE 2020 a Portuguese and European Union initiative through the Project POCI-01-0247-FEDER-072607, R&D and production of logos for the automotive industry. This research was sponsored by Norte2020, through European Social Fund (FSE), under the National Doctoral Program in “Surfaces Engineering and Protection”, NORTE-08-5369-FSE-000047. This research is sponsored by national funds through FCT—Fundação para a Ciência e a Tecnologia, under the Ph.D. Research Scholarship with Reference No. 2020.09436.BD. Author Maria José Lima acknowledges FCT for the research contract 2021.00675.CEECIND. This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of Strategic Funding (co-financed via UIDB/00285/2020 and UIDB/04650/2020) and LA/P/0112/2020

    An analysis of tacrolimus-related complications in the first 30 days after liver transplantation

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    OBJECTIVES: Orthotopic liver transplantation has improved survival in patients with end-stage liver disease; however, therapeutic strategies that achieve ideal immunosuppression and avoid early complications are lacking. To correlate the dose and level of Tacrolimus with early complications, e.g., rejection, infection and renal impairment, after liver transplantation. From November 2011 to May 2013, 44 adult liver transplant recipients were studied in this retrospective comparative study. RESULTS: The most frequent indication for liver transplantation was hepatitis C cirrhosis (47.7%), with a higher prevalence observed in male patients (68.18%). The ages of the subjects ranged from 19-71 and the median age was 55.5 years. The mean length of the hospital stay was 16.1±9.32 days and the mean Model for End-stage Liver Disease score was 26.18±4.28. There were five cases of acute cellular rejection (11.37%) and 16 cases of infection (36.37%). The blood samples that were collected and analyzed over time showed a significant correlation between the Tacrolimus blood level and the deterioration of glomerular filtration rate and serum creatinine (

    Achados hematológicos na síndrome de Noonan

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    OBJETIVO: A síndrome de Noonan é uma patologia de múltiplas anomalias congênitas e, dentre os achados clínicos, a diátese hemorrágica está incluída. O propósito deste estudo é determinar a freqüência de anormalidades hemostáticas nos pacientes afetados. MÉTODO: Nós estudamos 30 pacientes afetados pela síndrome quanto aos aspectos hematológicos que consistiu de tempo de sangramento, tempo de protrombina, tempo de tromboplastina parcial ativada, tempo de trombina, contagem de plaquetas e dosagem do fator de coagulação XI. RESULTADOS: Um resultado laboratorial anormal foi observado em 9 desses pacientes (30%). Apesar dos achados mais comuns terem sido as deficiências dos fatores de coagulação, especialmente do fator XI, também observamos anormalidades no número e na função plaquetária. CONCLUSÕES: Anormalidades hemostáticas são observadas com certa freqüência em pacientes com síndrome de Noonan (30% em nossa amostra). Enfatizamos, portanto, a importância de uma investigação hematológica mais detalhada nesses pacientes, especialmente antes da realização de um procedimento invasivo, o qual é requerido com certa freqüência na síndrome.OBJECTIVE: Noonan syndrome is a multiple congenital anomaly syndrome, and bleeding diathesis is considered part of the clinical findings. The purpose of this study was to determine the frequency of hemostatic abnormalities in a group of Noonan syndrome patients. METHOD: We studied 30 patients with clinical diagnosis of Noonan syndrome regarding their hemostatic status consisting of bleeding time, prothrombin time, activated partial thromboplastin time and thrombin time tests, a platelet count, and a quantitative determination of factor XI. RESULTS: An abnormal laboratory result was observed in 9 patients (30%). Although coagulation-factor deficiencies, especially factor XI deficiency, were the most common hematological findings, we also observed abnormalities of platelet count and function in our screening. CONCLUSIONS: Hemostatic abnormalities are found with some frequency in Noonan syndrome patients (30% in our sample). Therefore, we emphasize the importance of a more extensive hematological investigation in these patients, especially prior to an invasive procedure, which is required with some frequency in this disorder

    Are motivational and self-regulation factors associated with 12 months’ weight regain prevention in the NoHoW study? An analysis of European adults

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    © The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom‑ mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the dataPurpose: Preventing weight regain can only be achieved by sustained changes in energy balance-related behaviors that are associated with weight, such as diet and physical activity. Changes in motivation and self-regulatory skills can support long-term behavioral changes in the context of weight loss maintenance. We propose that experiencing a supportive climate care is associated with enhanced satisfaction of basic psychological needs, intrinsic goals, and autonomous motivation. These factors are expected to be associate with the utilization of self-regulation skills, leading to more sustained behavior changes and ultimately preventing weight regain. This hypothesis was tested in this ancillary analysis of the NoHoW trial, where the study arms were pooled and followed for 12 months. Methods: The NoHoW was a three-center, large-scale weight regain prevention full factorial trial. In this longitudinal study, data were collected in adults who lost > 5% weight in the past year (N = 870, complete data only, 68.7% female, 44.10 ± 11.86 years, 84.47 ± 17.03 kg) during their participation in a 12-month digital behavior change intervention. Weight and validated measures of motivational- and self-regulatory skills-related variables were collected at baseline, six- and 12 months. Change variables were used in Mplus' path analytical models informed by NoHoW's logic model. Results: The bivariate correlations confirmed key mediators' potential effect on weight outcomes in the expected causal direction. The primary analysis showed that a quarter of the variance (r2 = 23.5%) of weight regain prevention was achieved via the mechanisms of action predicted in the logic model. Specifically, our results show that supportive climate care is associated with needs satisfaction and intrinsic goal content leading to better weight regain prevention via improvements in self-regulatory skills and exercise-controlled motivation. The secondary analysis showed that more mechanisms of action are significant in participants who regained or maintained their weight. Conclusions: These results contribute to a better understanding of the mechanisms of action leading to behavior change in weight regain prevention. The most successful participants used only a few intrinsic motivation-related mechanisms of action, suggesting that habits may have been learned. While developing a digital behavior change intervention, researchers and practitioners should consider creating supportive climate care to improve needs satisfaction and intrinsic goal contents. Trial registration: ISRCTN, ISRCTN88405328 , registered 12/22/2016.The NoHoW study has received funding from the European Union’s Horizon 2020 Research and Innovation Programme (grant agreement number 643309).info:eu-repo/semantics/publishedVersio

    Business intelligence e o processo de gerenciamento de riscos em uma instituição pública: Business intelligence and the risk management process in a public institution

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    O Gerenciamento de risco é uma área de conhecimento utilizada por muitas organizações públicas e privadas e proporciona a análise e o mapeamento de possíveis eventos, que possam gerar danos no ambiente organizacional. Neste trabalho, buscou-se o conceito de gestão de risco para caracterizar o funcionamento de um sistema de controle de uma empresa pública, que possui uma ferramenta de Business Intelligence (BI) que possibilita analisar e identificar as causas e o nível de risco do ambiente tecnológico. A  gestão dos processos que envolvem a organização é realizada com o objetivo de prevenir danos, ataques e  prejuízos financeiros. O estudo demonstrou que a visualização de informações por meio de dashboard com gráficos e tabelas, auxilia de forma significativa a camada de apresentação para melhorar o processo de tomada de decisão dos gestores

    Marco activo de recursos de innovación docente: Madrid

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    Una guía de espacios e instituciones para actividades educativas complementarias en enseñanza secundaria y Formación Profesional
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