Experimental and statistical study of three adherence tests for an epoxy-amine/aluminum alloy system: Pull-Off, Single Lap Joint and Three-Point Bending tests

The mechanical resistance of a bonded joint depends on the adhesive interaction onto the substrate and the mechanical properties of the adhesive itself. Many existing tests can be useful for measuring the adherence or evaluating mechanical adhesive response. All these tests do not provide the same information: in particular, adherence measurements can be split into initiation tests and propagation ones. In this paper, three adherence tests have been considered for the evaluation of the fracture initiation between a poly-epoxide adhesive (a mixture of pure epoxy and amine) and an aluminum surface (AA 2024-T3), namely the Pull-Off, Single Lap Joint (SLJ) and Three-Point Bending tests. Various surface preparation protocols before bonding have been tested and optimized for aluminum substrates, including mechanical and chemical surface treatments, followed by the application of an appropriate primer before bonding. This study paves the way for the future development of adhesive systems as it provides reliable surface preparation protocols for aluminum surfaces and gives an insight into the choice of an adequate adherence test dedicated to high-performance adhesives. The load at break (FMax), the experimental error, the failure mode and statistical studies according to the Weibull model and Principal Component Analysis (PCA) were studied on each surface preparation configuration. It has been shown that the application of a primer, especially a sol-gel product increases the load at break and provides more reliable results. Then, this paper shows that the two tests can quantify the failure initiation and distinguish the different surface preparation efficiency, are the Single Lap Joint test (mode II or mode I + II) and the Three-Point Bending test (mode I), with an increase of the results reliability with the latter one. The Pull-Off test (mode I) is useful as a routine checking, and particularly interesting because its response does not depend on the substrate thickness, even though it cannot highlight the difference between all surface preparations

Relationship between childhood physical abuse and clinical severity of treatment-resistant depression in a geriatric population

Introduction: We assessed the correlation between childhood maltreatment (CM) and severity of depression in an elderly unipolar Treatment-Resistant Depression (TRD) sample. Methods: Patients were enrolled from a longitudinal cohort (FACE-DR) of the French Network of Expert TRD Centres. Results: Our sample included 96 patients (33% of the overall cohort) aged 60 years or above, with a mean age of 67.2 (SD = 5.7). The majority of the patients were female (62.5%). The Montgomery and Asberg Depression Rating Scale (MADRS) and Quick Inventory Depression Scale-Self Report (QIDS-SR) mean scores were high, 28.2 (SD = 7.49) [MADRS score range: 0–60; moderate severity≥20, high severity≥35] and 16.5 (SD = 4.94) [IDS-SR score range: 0–27; moderate severity≥11, high severity≥16], respectively. Mean self-esteem scores were 22.47 (SD = 6.26) [range 0–30]. In an age- and sex-adjusted model, we found a positive correlation between childhood trauma (CTQ scores) and depressive symptom severity [MADRS (β = 0.274; p = 0.07) and QIDS-SR (β = 0.302; p = 0.005) scores]. We detected a statistically significant correlation between physical abuse and depressive symptom severity [MADRS (β = 0.304; p = 0.03) and QIDS-SR (β = 0.362; p = 0.005) scores]. We did not observe any significant correlation between other types of trauma and depressive symptom severity. We showed that self-esteem (Rosenberg scale) mediated the effect of physical abuse (PA) on the intensity of depressive symptoms [MADRS: b = 0.318, 95% BCa C.I. [0.07, 0.62]; QIDS-SR: b = 0.177, 95% BCa C.I. [0.04, 0.37]]. Preacher & Kelly’s Kappa Squared values of 19.1% (k2 = 0.191) and 16% (k2 = 0.16), respectively for the two scales, indicate a moderate effect. Conclusion: To our knowledge, this is the first study conducted in a geriatric TRD population documenting an association between childhood trauma (mainly relating to PA) and the intensity of depressive symptoms

Tritium dating of dripwater from Villars Cave (SW-France)

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Shared Decision-Making: a Systematic Review Focusing on Mood Disorders

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Occurrence of side effects in treatment-resistant depression: role of clinical, socio-demographic and environmental characteristics

International audienceIntroduction: Treatment-resistant depression (TRD) is a disabling psychiatric condition characterized by the failure of two antidepressants (ADs). Since the occurrence of side effects (SEs) appears to be one of the main determinants of early discontinuation of pharmacological treatments contributing to a pseudo-resistance, the purpose of this study was to determine the parameters associated with the occurrence of SEs under ADs in a cohort of patients with TRD.Methods: An observational, cross-sectional, multicentre study was carried out using data from the French network of Expert Centers for TRD. For the 108 patients enrolled in the study, the statistical analyses focused on the overall occurrence and on the profile of the SEs (9 categories, 32 items).Results: SEs were influenced by age and sex and were positively associated with the intensity of anxious, depressive and suicidal symptoms, a history of childhood trauma (sexual abuse, emotional abuse and neglect), and negatively associated with self-esteem, and assessment of overall functioning.Conclusion: Using variables accessible in common practice, these results fall within the dynamic of a more tailored approach to medicine that could allow, through integrated pharmacological management, the continuation of antidepressant treatments, and therefore limit the risk of therapeutic failure

Le projet collectif de recherche « Grotte de Cussac » (Dordogne, France) : étude d’une cavité ornée à vestiges humains du Gravettien

CD p. 325-342International audienc

Diurnal symptoms of sleepiness and dysfunction predict future suicidal ideation in a French cohort of outpatients (FACE-DR) with treatment resistant depression: A 1-year prospective study about sleep markers

International audienceBackground: Patients suffering from treatment-resistant depression (TRD) are at risk of suicide. Sleep and circadian rhythm alterations are widely recognized as core symptoms of major depressive disorder and are associated with suicidal ideation. Thus, sleep and circadian rhythm alterations may be targeted to prevent suicide.Methods: Patients were recruited from a prospective cohort of the French network of TRD expert centers. Mood, sleep and circadian rhythms were assessed at baseline; suicidal risk was assessed both at baseline and during a one-year follow-up with standardized subjective questionnaires.Results: Excessive daytime sleepiness (adjusted odds ratio aOR = 1.7(1-3.3), p = 0.04) and daytime dysfunction (aOR = 1.81(1.16-2.81), p = 0.0085) increased the risk of suicidal thoughts over the one-year follow-up period in patients with TRD after adjustment on age, gender, depression, trauma, anxiety, impulsivity, current daily tobacco smoking and body mass index. Hypnotics intake is associated with a reduced risk of suicidal ideation at one-year follow-up after the same adjustments (OR = 0.73(0.56-0.95), p = 0.019). Other associations between sleep quality or circadian rhythms and suicidal ideations at either baseline or one year did not remain significant in multivariate analyses after the same adjustments.Limitations: Sleep assessments were based on self-reported questionnaires rather than objective measures.Conclusions: Daytime sleepiness and dysfunction are predictors of suicidal ideations, whereas hypnotics intake is associated with a reduced risk of suicidal ideations. Diurnal symptoms of sleep disturbances are therefore red flags to target for preventing suicide in depressed patients, and hypnotics seem efficient in preventing suicide for patients with TRD

Le projet collectif de recherche « Grotte de Cussac » (Dordogne, France) : étude d’une cavité ornée à vestiges humains du Gravettien

CLOTTES J. (dir.) 2012.-L'art pléistocène dans le monde / Pleistocene art of the world / Arte pleistoceno en el mundo Actes du Congrès IFRAO, Tarascon-sur-Ariège, septembre 2010-Symposium « Art pléistocène en Europe » Le projet collectif de recherche « Grotte de Cussac » (Dordogne, France) : étude d'une cavité ornée à vestiges humains du Gravettie

Le projet collectif de recherche « Grotte de Cussac » (Dordogne, France) : étude d’une cavité ornée à vestiges humains du Gravettien

International audienceCLOTTES J. (dir.) 2012.-L'art pléistocène dans le monde / Pleistocene art of the world / Arte pleistoceno en el mundo Actes du Congrès IFRAO, Tarascon-sur-Ariège, septembre 2010-Symposium « Art pléistocène en Europe » Le projet collectif de recherche « Grotte de Cussac » (Dordogne, France) : étude d'une cavité ornée à vestiges humains du Gravettie

Our reference: JQI 6008

International audienceIn this article, we present a first synthesis of the chronology of Cussac Cave (Dordogne, SW France). This deep cavern (1.6 km), discovered in 2000, is very well preserved (e.g. intact floors) and thus favorable to research, especially given its rare association of parietal art and human remains, deposited in at least three locations. The scientific team working since 2009 presents here a first diachronic reconstruction of the natural (geological, biological) and anthropogenic (cultural, spiritual) elements relevant to the sectors of the cave accessible for study.In addition to the nuclear dating methods commonly used in karst contexts and decorated sites (U–Th and 14C for speleothems, 14C-AMS for organic materials, bone and charcoal), we drew upon other disciplines to determine the relative chronology of the events that occurred in the cave: geosciences (karstology, sedimentary geology, geoarchaeology), biological anthropology, paleontology, zooarchaeology, anthracology, ichnology, lithic and osseous technology, and of course, the study of parietal art. Their integrated study enabled us to define a coherent and global chronological framework.The results confirm that bears frequented the cavity several times before any human incursions. Humans later ventured into the cave after it had already undergone several phases of karstogenesis, collapse, sedimentation, erosion and concretion formation. The nuclear methods and relative dating methods employed concur in favor of the hypothesis of human incursions only during the Middle Gravettian period, approximately 28–29,000 cal BP, to carry out spiritual, graphic and sepulchral activities. After the cave was abandoned by Gravettian people, some final sedimentary and biological events occurred (partial flooding, concretion formation, presence of mesofauna and microfauna, etc.), but were insufficient to significantly modify the decorated and sepulchral sanctuary. Later human frequentations (Late Glacial, Late Magdalenian, Late Neolithic) are quantitatively anecdotal and, most importantly, were limited to the cave porch and vestibular areas, which were sealed-off from the internal zone by rockfall debris and Late Glacial or Holocene concretion formations