415 research outputs found

    LAser Shock Adhesion Test (LASAT), an innovation dedicated to industry

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    NonWOSAvailable online for free at http://www.ila.org.in/kiran/kiran_19_2.pdfInternational audienc

    Aberrant computational mechanisms of social learning and decision-making in schizophrenia and borderline personality disorder

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    Psychiatric disorders are ubiquitously characterized by debilitating social impairments. These difficulties are thought to emerge from aberrant social inference. In order to elucidate the underlying computational mechanisms, patients diagnosed with major depressive disorder (N = 29), schizophrenia (N = 31), and borderline personality disorder (N = 31) as well as healthy controls (N = 34) performed a probabilistic reward learning task in which participants could learn from social and nonsocial information. Patients with schizophrenia and borderline personality disorder performed more poorly on the task than healthy controls and patients with major depressive disorder. Broken down by domain, borderline personality disorder patients performed better in the social compared to the non-social domain. In contrast, controls and MDD patients showed the opposite pattern and SCZ patients showed no difference between domains. In effect, borderline personality disorder patients gave up a possible overall performance advantage by concentrating their learning in the social at the expense of the non-social domain. We used computational modeling to assess learning and decision-making parameters estimated for each participant from their behavior. This enabled additional insights into the underlying learning and decision-making mechanisms. Patients with borderline personality disorder showed slower learning from social and non-social information and an exaggerated sensitivity to changes in environmental volatility, both in the non-social and the social domain, but more so in the latter. Regarding decision-making the modeling revealed that compared to controls and major depression patients, patients with borderline personality disorder and schizophrenia showed a stronger reliance on social relative to non-social information when making choices. Depressed patients did not differ significantly from controls in this respect. Overall, our results are consistent with the notion of a general interpersonal hypersensitivity in borderline personality disorder and schizophrenia based on a shared computational mechanism characterized by an over-reliance on beliefs about others in making decisions and by an exaggerated need to make sense of others during learning specifically in borderline personality disorder

    Methylation of phenol over high-silica beta zeolite: effect of zeolite acidity and crystal size on catalyst behaviour

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    A systematic investigation was carried out to elucidate several aspects of the gas/solid methylation of phenol over high Si/Al ratio beta-structured zeolite in protonated form, characterised by various techniques, including XRD, SEM, BET, ICP, FTIR, TGA, microcalorimetry, and modeling by ab initio calculations. Data on the characteristics and the kinetic and mechanistic features of the catalytic reaction, as well as on catalyst deactivation, show that these zeolites, besides being very active for the present reaction, lead to cresols and anisole as primary products. As catalyst deactivation proceeds, the selectivity to cresols and anisole increases substantially, accompanied by a rapid decrease in selectivity to polyalkylated species. Medium- to low-strength silanols are the main contributors to catalyst surface acidity. High-strength Lewis acid sites either are virtually absent (especially when metal cations partially substitute for protons) or play a role essentially in catalyst deactivation. Stacking faults in the zeolite framework, generated by the intergrowth of at least two beta polymorphs, lead to an increased concentration of silanol-based Br\uf8nsted acid sites. Deactivation is due to the interaction of phenol and oxygenated products with the silanol-based acid sites and of methanol only with the strong acid sites of both Lewis and Br\uf8nsted nature. Self-oligomerisation\u2013cyclisation of methanol to olefins and aromatics, followed by further alkylation to aromatic C atoms, contributes to catalyst deactivation. At any conversion level and at any temperature, the anisole/cresol ratio is systematically lower for the larger-crystal size zeolite, because the secondary transformations of anisole to cresols by both intramolecular rearrangement and intermolecular alkylation of phenol is favoured by the longer residence time of anisole within the zeolite pores

    Advanced Differentiated Thyroid Cancer. A Complex Condition Needing a Tailored Approach

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    Differentiated thyroid cancers (DTCs) are slow-growing malignant tumours, including papillary and follicular carcinomas. Overall, prognosis is good, although it tends to worsen when local invasion occurs with bulky cervical nodes, or in the case of distant metastases. Surgery represents the main treatment for DTCs. However, radical excision is challenging and significant morbidity and functional loss can follow the treatment of the more advanced forms. Literature on advanced thyroid tumours, both differentiated and undifferentiated, does not provide clear and specific guidelines. This emerges the need for a tailored and multidisciplinary approach. In the present study, we report our single-centre experience of 111 advanced (local, regional, and distant) DTCs, investigating the rate of radical excision, peri-procedural and post-procedural complications, quality of life, persistence, recurrence rates, and survival rates. Results are critically appraised and compared to the existing published evidence review

    Hodgkin's lymphoma: The pathologist's viewpoint

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    Despite its well known histological and clinical features, Hodgkin's lymphoma (HL) has recently been the object of intense research activity, leading to a better understanding of its phenotype, molecular characteristics, histogenesis, and possible mechanisms of lymphomagenesis. There is complete consensus on the B cell derivation of the tumour in most cases, and on the relevance of Epstein-Barr virus infection and defective cytokinesis in at least a proportion of patients. The REAL/WHO classification recognises a basic distinction between lymphocyte predominance HL (LP-HL) and classic HL (CHL), reflecting the differences in clinical presentation and behaviour, morphology, phenotype, and molecular features. CHL has been classified into four subtypes: lymphocyte rich, nodular sclerosing, with mixed cellularity, and lymphocyte depleted. The borders between CHL and anaplastic large cell lymphoma have become sharper, whereas those between LP-HL and T cell rich B cell lymphoma remain ill defined. Treatments adjusted to the pathobiological characteristics of the tumour in at risk patients have been proposed and are on the way to being applied

    Generation of a new mouse model of glaucoma characterized by reduced expression of the AP-2β and AP-2δ proteins

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    We generated 6 transgenic lines with insertion of an expression plasmid for the R883/M xanthine dehydrogenase (XDH) mutant protein. Approximately 20% of the animals deriving from one of the transgenic lines show ocular abnormalities and an increase in intra-ocular pressure which are consistent with glaucoma. The observed pathologic phenotype is not due to expression of the transgene, but rather the consequence of the transgene insertion site, which has been defined by genome sequencing. The insertion site maps to chromosome 1qA3 in close proximity to the loci encoding AP-2\u3b2 and AP-2\u3b4, two proteins expressed in the eye. The insertion leads to a reduction in AP-2\u3b2 and AP-2\u3b4 levels. Down-regulation of AP-2\u3b2 expression is likely to be responsible for the pathologic phenotype, as conditional deletion of the Tfap2b gene in the neural crest has recently been shown to cause defective development of the eye anterior segment and early-onset glaucoma. In these conditional knock-out and our transgenic mice, the morphological/histological features of the glaucomatous pathology are surprisingly similar. Our transgenic mouse represents a model of angle-closure glaucoma and a useful tool for the study of the pathogenesis and the development of innovative therapeutic strategies
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