549 research outputs found
LAser Shock Adhesion Test (LASAT), an innovation dedicated to industry
NonWOSAvailable online for free at http://www.ila.org.in/kiran/kiran_19_2.pdfInternational audienc
Methylation of phenol over high-silica beta zeolite: effect of zeolite acidity and crystal size on catalyst behaviour
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
Aberrant computational mechanisms of social learning and decision-making in schizophrenia and borderline personality disorder
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
Hodgkin's lymphoma: The pathologist's viewpoint
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
Advanced Differentiated Thyroid Cancer. A Complex Condition Needing a Tailored Approach
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
Circulating extracellular vesicles are endowed with enhanced procoagulant activity in SARS-CoV-2 infection
Activation of the JAK/STAT pathway leads to proliferation of ST14A central nervous system progenitor cells
We were interested in whether central nervous system progenitor cells possess the signal transduction machinery necessary to mediate cytokine functions and whether this machinery can become activated upon stable expression of a particular cytokine receptor. For this purpose we utilized a previously obtained conditionally immortalized striatum-derived nestin-positive cell line (ST14A). We found that ST14A cells express Jak2, but not Jak1 or Tyk2. An identical pattern of expression was found in embryonic striatal tissue. To evaluate the susceptibility of these cytokine specific cytoplasmic transducers to activation, ST14A cells were stably transfected with the alpha and beta (AIC2A) chains of the murine interleukin-3 receptor. Four independent lines expressing both the alpha and beta receptor subunits were obtained. We found that cells from each of these lines were induced to proliferate upon exposure to interleukin-3. Dose response curve, antibody blocking experiments and binding studies revealed that the response was mediated by the reconstituted high affinity interleukin-3 receptor. Immunoprecipitation studies on these cells showed that Jak2 and Stat5 were being phosphorylated after stimulation of the reconstituted receptor. These results indicate that members of the JAK/STAT family of proteins are expressed in central nervous system progenitor cells and are susceptible to activation through stimulation of an exogenously expressed cytokine receptor, ultimately leading to cell proliferation
Building capacity to provide innovative interventions for early psychosis in mental health professionals
Abstract
Despite international guidelines, cognitive behavioural therapy for early psychosis (CBTep) is still under-used in daily clinical practice, mainly due to the lack of specific skills among mental health professionals. The aim of the study was to evaluate the feasibility and efficacy of a CBTep training course and to investigate the impact of trainees' variables on the level of skills acquisition. An intensive and graded CBTep training programme consisting of 112 hours of plenary lectures, 30 hours of group supervision and 3 months of practical training was offered to mental health professionals of 65 Italian community Mental Health Centers (CMHCs). CBT expert psychologists were used as the comparison group. Participants underwent pre-planned exams to test the level of skills acquisition and were requested to complete a satisfaction survey. The vast majority of participants (93%) completed the training with medium–high evaluation scores and reported to be highly satisfied with the course. CMHCs staff members achieved high scores in the examinations and no major differences between them and CBT expert psychologists were found in most of the final exam scores. Our results support the feasibility and the efficacy of the training to build specific CBTep capacity in a large cohort of professionals working in Italian Generalist Mental Health Services.
Key learning aims
(1)
To understand the capacity building of a short training programme in CBT for early psychosis dedicated to community mental health professionals.
(2)
To consider the optimal characteristics of a CBT training programme for early psychosis.
(3)
To reflect on the feasibility of a CBT training programme for early psychosis in the context of Italian Community Mental Health Services
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