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The Application of Reliability allocation methodology, from preliminary test data, to design a Definitive test plan. Application to Mechanical Heart Replacement Technology
The objective of this paper is to demonstrate the utility and relevance of the use of reliability allocation methodology in the design of reliability test plans for the qualification of new medical systems. This approach makes use of all of the information collected in the preliminary product development phases. Firstly, this methodology provides a resolution to optimizing the reliability allocation process for the design of a reliability test plan, with a view to cost containment and, secondly, demonstrates the applicability to the demanding constraints provided by the medical sector, and in particular, those in the field of Mechanical Heart Replacement Therapy. The Carmat Total Artificial Heart was the subject of this study, possibly the most demanding of reliability requirements, as it replaces the heart of patients with irreversible bi-ventricular heart failure and who are, consequently, totally reliable on the device for survival
Modèles anciens et nouvelle leçon de vie : la uirtus, des premiers apologistes latins à Lactance, le « Cicéron chrétien
Les mécanismes cognitifs d’acceptation d’une innovation alimentaire de discontinuité : le cas des insectes en France
Dans un contexte de mutation des modes de consommation alimentaire, les innovations de discontinuité constituent en enjeu considérable pour l’industrie. L’objectif de cet article est d’identifier les processus cognitifs d’acceptation d’une innovation alimentaire de discontinuité à travers l’étude des mécanismes de classification et d’encodage de la catégorisation. Une étude qualitative appliquée à la consommation humaine d’insectes permet d’identifier ces mécanismes en fonction du degré de transformation des produits, et leurs effets sur l’acceptation par les consommateurs. Ces résultats permettent notamment d’enrichir la théorie du comportement décisionnel et visent à éclairer les fabricants sur les leviers marketing à actionner pour faire accepter une innovation alimentaire de discontinuité
Quelles synergies pour améliorer l'orientation et l'accompagnement à l'emploi dans l'insertion par l'économique ?
Is less more or a bore? Package design simplicity and brand perception: an application to Champagne
Packaging design as a medium for brand communication has a strong impact on the point-of-purchase decision. Therefore, marketers need a keen understanding of how packaging design influences brand perception. Although many studies have investigated the impact of design elements like color or typeface, few have examined the impact of holistic variables like the degree of elaborateness. This study proposes to fill this gap by investigating the influence of the degree of simplicity/complexity in package design on brand perception. The topic is first investigated through a multidisciplinary approach mobilizing the fields of semiotics, art history and marketing. Then, we conduct an experiment in which three bottles of Champagne operationalizing three levels of simplicity/complexity are tested with a sample of 305 consumers. The results indicate that the simplicity/complexity of a package design has a significant impact on brand perception, with simplicity being associated with modernity, reliability, authenticity, success and sobriety and complexity with seniority, joy, imagination, charm, femininity and sophistication
Work-Related Stressors and Increased Risk of Benzodiazepine Long-Term Use: Findings From the CONSTANCES Population-Based Cohort
OBJECTIVES: To examine whether stressful job exposure to the public could be associated with having long-term benzodiazepine use.
METHODS: From the participants included between 2012 and 2016 in the French population-based CONSTANCES cohort, 13 934 men and 19 261 women declared a daily job exposure to the public and rated the frequency of stressful exposure. We examined benzodiazepine long-term use by using drug reimbursement administrative registries. Logistic regressions provided odds ratios (ORs) of benzodiazepine long-term use, with stratification for gender and adjustment for age, education, and area deprivation index. Occupational grade, job strain, depression, self-rated health, and alcohol use disorder were additional stratification variables.
RESULTS: Benzodiazepine long-term use was positively associated with stressful exposure to the public ("often or always" vs "rarely or never") in men (OR = 2.2; 95% confidence interval [CI] = 1.8, 2.8) and women (OR = 1.6; 95% CI = 1.4, 1.9), with dose-dependent relationships (P trends < .001). Adjustments and analyses in subgroups without other individual or environmental vulnerability factors led to similar results.
CONCLUSIONS: Stressful job exposure to the public increases the risk of benzodiazepine long-term use. Prevention programs aiming at reducing the burden of benzodiazepine long-term use would benefit in targeting this specific population
Maternal ageing impairs mitochondrial DNA kinetics during early embryogenesis in mic
STUDY QUESTION: Does ageing affect the kinetics of the mitochondrial pool during oogenesis and early embryogenesis?
SUMMARY ANSWER: While we found no age-related change during oogenesis, the kinetics of mitochondrial DNA content and the expression of the factors involved in mitochondrial biogenesis appeared to be significantly altered during embryogenesis.
WHAT IS KNOWN ALREADY: Oocyte mitochondria are necessary for embryonic development. The morphological and functional alterations of mitochondria, as well as the qualitative and quantitative mtDNA anomalies, observed during ovarian ageing may be responsible for the alteration of oocyte competence and embryonic development.
STUDY DESIGN, SIZE, DURATION: The study, conducted from November 2016 to November 2017, used 40 mice aged 5-8 weeks and 45 mice aged 9-11 months (C57Bl6/CBA F(1)). A total of 488 immature oocytes, with a diameter ranging from 20 μm to more than 80 μm, were collected from ovaries, and 1088 mature oocytes or embryos at different developmental stages (two PN, one-cell, i.e. syngamy, two-cell, four-cell, eight-cell, morula and blastocyst) were obtained after ovarian stimulation and, for embryos, mating.
PARTICIPANTS/MATERIALS, SETTING, METHODS: Mitochondrial DNA was quantified by quantitative PCR. We used quantitative reverse transcriptase PCR (RT-PCR) (microfluidic method) to study the relative expression of three genes involved in the key steps of embryogenesis, i.e. embryonic genome activation (HSPA1) and differentiation (CDX2 and NANOG), two mtDNA genes (CYB and ND2) and five genes essential for mitochondrial biogenesis (PPARGC1A, NRF1, POLG, TFAM and PRKAA). The statistical analysis was based on mixed linear regression models applying a logistic link function (STATA v13.1 software), with values of P < 0.05 being considered significant.
MAIN RESULTS AND THE ROLE OF CHANCE: During oogenesis, there was a significant increase in oocyte mtDNA content (P < 0.0001) without any difference between the two groups of mice (P = 0.73). During the first phase of embryogenesis, i.e. up to the two-cell stage, embryonic mtDNA decreased significantly in the aged mice (P < 0.0001), whereas it was stable for young mice (young/old difference P = 0.015). The second phase of embryogenesis, i.e. between the two-cell and eight-cell stages, was characterized by a decrease in embryonic mtDNA for young mice (P = 0.013) only (young/old difference P = 0.038). During the third phase, i.e. between the eight-cell and blastocyst stage, there was a significant increase in embryonic mtDNA content in young mice (P < 0.0001) but not found in aged mice (young/old difference P = 0.002). We also noted a faster expression of CDX2 and NANOG in the aged mice than in the young mice during the second (P = 0.007 and P = 0.02, respectively) and the third phase (P = 0.01 and P = 0.008, respectively) of embryogenesis. The expression of mitochondrial genes CYB and ND2 followed similar kinetics and was equivalent for both groups of mice, with a significant increase during the third phase (P < 0.01). Of the five genes involved in mitochondrial biogenesis, i.e. PPARGC1A, NRF1, POLG, TFAM and PRKAA, the expression of three genes decreased significantly during the first phase only in young mice (NRF1, P = 0.018; POLGA, P = 0.002; PRKAA, P = 0.010), with no subsequent difference compared to old mice. In conclusion, during early embryogenesis in the old mice, we suspect that the lack of a replicatory burst before the two-cell stage, associated with the early arrival at the minimum threshold value of mtDNA, together with the absence of an increase of mtDNA during the last phase, might potentially deregulate the key stages of early embryogenesis.
LARGE SCALE DATA: N/A.
LIMITATIONS, REASONS FOR CAUTION: Because of the ethical impossibility of working on a human, this study was conducted only on a murine model. As superovulation was used, we cannot totally exclude that the differences observed were, at least partially, influenced by differences in ovarian response between young and old mice.
WIDER IMPLICATIONS OF THE FINDINGS: Our findings suggest a pathophysiological explanation for the link observed between mitochondria and the deterioration of oocyte quality and early embryonic development with age.
STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the University of Angers, France, by the French national research centres INSERM and the CNRS and, in part, by PHASE Division, INRA. There are no competing interests
The development of gerontechnology for hospitalized frail elderly people: The ALLEGRO hospital-based geriatric living lab
Our objective was to bridge the gap between gerontechnology developers and hospitalized frail elderly people, in order to promote open gerontechnology innovation in hospitals. We designed a hospital-based living lab that provides reflexive "idea incubator workshops" that gather both the users and the developers of technology, supplemented with an "experimental hospital room" for the testing of devices by older inpatients. The ALLEGRO living lab was delivered in 2018 at the Geriatric Department of Angers University Hospital, France. The workshops and experimental hospital room should help frail older inpatients to participate in the co-design and co-development of new technologies to improve hospital care and promote successful aging