794 research outputs found

    New Multiphase CP and DP 1000 MPa strength level grades for improved performance after hot forming

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    Pure martensitic steels have after hot forming limited performance in terms of rest ductility which limits the application in crash relevant parts. New steel grades were designed in the EU project HOTFORM including the corresponding process routes. These steel grades have ferritic-martensitic dual phase (DP) and martensitic-bainitic complex phase (CP) microstructures after hot forming process. The laboratory tests show an improved formability after hot forming. The basic concepts of the new alloys are explained. Furthermore, for validation of upscaling purposes a semi-industrial test is carried out and the results are discussed. The main application is for vehicle safety. This is evaluated by comparing the crash performance of these hot formed grades with cold rolled DP1000 and CP1000 for crash cans in a drop tower test.The research leading to these results was carried out in the framework of HOTFORM project with a financial grant of the Research Programme RFCS (Research Funds for Coal and Steel) under grant agreement (RFSR-CT-2015-00017)

    Characterization of a Medium Mn-Ni Steel Q&P Treated by a High Partitioning Temperature Cycle

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    In this work, a medium Mn-Ni steel was treated through Quenching and Partitioning (Q&P) with a partitioning temperature (PT) of 650 °C, which corresponded to the start of the austenite reverse transformation (ART) phenomenon. The influence of the quenching temperature (QT) and partitioning time (Pt) on austenite stabilization and mechanical properties was investigated. A strong influence of the quenching temperature was observed. Results were compared with those obtained after a Q&P treatment with 400 °C partitioning temperature. The Q&P cycle with quenching to room temperature and a high partitioning temperature produced a steel with a high retained austenite (RA) volume fraction and exceptional strength–ductility balance. The analysis of the mechanical stability of the retained austenite revealed a significant stress-induced transformation. Nevertheless, the austenite, which was stable at stresses above the yield stress, provided significant TRIP-assisted ductility. Bending, hole expansion and post-stamping properties were also evaluated for the most promising conditions.This research was funded by the Research Fund for Coal and Steel, grant number 70985

    The indirect effect of cognitive reserve on the relationship between age and cognition in pathological ageing: A cross-sectional retrospective study in an unselected and consecutively enrolled sample

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    Cognitive reserve (CR) allows individuals to maintain cognitive functionality even in the presence of pathologies. The compensation hypothesis suggests that CR plays an indirect role between age and cognitive decline, contrasting the negative effect of ageing on cognition. We test this hypothesis in an unselected and consecutively enrolled sample of memory clinic attendees (n = 134) who completed the CR Index questionnaire and three neuropsychological tests assessing global cognition (MMSE, FAB, CDT). Participants were divided into two groups based on standard diagnostic criteria (DSM-5): those who were cognitively impaired (n = 92) and those who were preserved (n = 42). A principal component analysis was used to extract a composite measure of global cognitive functioning from the three neuropsychological tests, and mediation analysis was used to examine the relationship between CR, age and global cognitive functioning in the two groups. Results revealed that: (i) age had a significant direct negative effect on the global cognitive score in both groups; (ii) the three socio-behavioural proxies of CR together suppress the direct negative relationship between age and global cognitive score in cognitively impaired patients but not in cognitively preserved participants. This study confirms the association between CR, age and cognition and allows us to validate its role in a population with cognitive impairment and extend findings to a low-to-middle educated population. These results hold important implications for public health and wellness promotion, emphasising the beneficial role of maintaining healthy and active physical, cognitive and social lifestyles

    Brainstem lesions in permanent vegetative state

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    Vegetative state has mainly been associated with widespread damage of cortex, white matter and/or thalamus, whereas brainstem findings are usually absent or include focal, slight and non-haemorrhagic lesions. Functional integrity of the brainstem is considered to be necessary for preservation of sleep/wake cycle (arousal and wakefulness), particularly midline structures of the upper pons and midbrain. Awareness, instead, mainly relies on the integrity of the cerebral cortex, white matter, basal ganglia and thalamus. We present here the neuroanatomical study of a case of post-traumatic permanent vegetative state which is characterized by a quite complex damage also at the level of the brainstem. After a car accident a young woman was referred to Neurosurgical Unit in coma and paraplegia due to head injury and C2 fracture. Spontaneous sleep/wake cycle recovered in the following months. Magnetic resonance, performed one month after the trauma, showed injuries of midbrain, thalamus and left frontal lobe. The patient died more than 15 years after the trauma. Macroscopic examination showed generalized hypotrophy of cerebral hemispheres, cerebellum and brainstem. Partial degeneration of the basal ganglia and severe volumetric reduction of the hemispheric white matter were observed. Wide and bilateral thalamic necrosis and degeneration was found. Transverse sections of the brainstem showed degeneration of the descending and ascending systems of motor and sensitive fibres, and neuronal loss in the inferior olivary complex, pontine nuclei, red nucleus and substantia nigra. In the midbrain, areas of necrosis with reactive astrogliosis extended from the mesencephalic aqueduct towards the interpeduncular fossa, affecting the periaqueductal grey matter, and the dorsal and median raphe nuclei. On the basis of the neuroanatomic description of the damaged areas, we discuss the role of the midbrain reticular activating system and possible plasticity responses in the mechanisms of arousal/wakefulness

    Analysis of tapered front-coupling X-ray waveguides.

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    The coupling and propagation of electromagnetic waves through planar X-ray waveguides (WG) with vacuum gap and Si claddings are analyzed in detail, starting from the source and ending at the detector. The general case of linearly tapered WGs (i.e. with the entrance aperture different from the exit one) is considered. Different kinds of sources, i.e. synchrotron radiation and laboratory desk-top sources, have been considered, with the former providing a fully coherent incoming beam and the latter partially coherent beams. It is demonstrated that useful information about the parameters of the WG can be derived, comparing experimental results with computer simulation based on analytical solutions of the Helmholtz equation which take into account the amplitude and phase matching between the standing waves created in front of the WG, and the resonance modes propagating into the WG

    Exploring a tissue engineering strategy as a novel approach for haemophilic arthropathy treatment

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    Among the most disabling complications of Haemophilia, repeated and sponta- neous intra-articular haemorrhages may cause irreversible damage to the joint. This leads to haemophilic arthropathy, a polyarticular disease characterized by joint stiff- ness, chronic pain and a severely limited range of motion. Occurrence of haemophilic arthropathy can be avoided by the prophylactic administration of clotting factors to prevent articular haemorrhages, but it can also be addressed using anti-inflammatory drugs and surgery to alleviate the effects of articular damage, up to arthroplasty as resolute option [1]. However, innovative strategies for the prevention and treatment of this common and serious complication are still required, due to some important limits of current therapies, first of all inhibitor development. In this work, we inves- tigated a tissue engineering approach to regenerate articular focal lesions in Haemo- philic patients by in vitro development of an autologous bio-hybrid prosthesis. For this purpose, we isolated articular chondrocytes from Haemophilic patients (HaeCs) and characterized them for the first time in literature, to verify whether they were altered by blood exposure. Using healthy chondrocytes as control, optical microscope morphological analysis, flow cytometry immunophenotype evaluation and gene expression study by qRT-PCR were performed. After that, an innovative compos- ite scaffold was obtained by combining decellularized Wharton’s Jelly (W’s J) from human umbilical cord with a novel biodegradable polyvinyl alcohol (PVA) hydrogel [2]. Finally, we assessed HaeCs capacity to re-populate biosynthetic scaffolds by Scan- ning Electron Microscopy and MTT assay on cells seeded on supports. Taken togeth- er, our results contributed to define HaeCs phenotype, highlighting the possibility to use these cells for autologous implant. What is more, HaeCs capacity to growth and proliferate on composite scaffolds set the stage for planning the development of autologous tissue substitutes for haemophilic cartilage regeneration

    Off-label long acting injectable antipsychotics in real-world clinical practice: a cross-sectional analysis of prescriptive patterns from the STAR Network DEPOT study

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    Introduction Information on the off-label use of Long-Acting Injectable (LAI) antipsychotics in the real world is lacking. In this study, we aimed to identify the sociodemographic and clinical features of patients treated with on- vs off-label LAIs and predictors of off-label First- or Second-Generation Antipsychotic (FGA vs. SGA) LAI choice in everyday clinical practice. Method In a naturalistic national cohort of 449 patients who initiated LAI treatment in the STAR Network Depot Study, two groups were identified based on off- or on-label prescriptions. A multivariate logistic regression analysis was used to test several clinically relevant variables and identify those associated with the choice of FGA vs SGA prescription in the off-label group. Results SGA LAIs were more commonly prescribed in everyday practice, without significant differences in their on- and off-label use. Approximately 1 in 4 patients received an off-label prescription. In the off-label group, the most frequent diagnoses were bipolar disorder (67.5%) or any personality disorder (23.7%). FGA vs SGA LAI choice was significantly associated with BPRS thought disorder (OR = 1.22, CI95% 1.04 to 1.43, p = 0.015) and hostility/suspiciousness (OR = 0.83, CI95% 0.71 to 0.97, p = 0.017) dimensions. The likelihood of receiving an SGA LAI grew steadily with the increase of the BPRS thought disturbance score. Conversely, a preference towards prescribing an FGA was observed with higher scores at the BPRS hostility/suspiciousness subscale. Conclusion Our study is the first to identify predictors of FGA vs SGA choice in patients treated with off-label LAI antipsychotics. Demographic characteristics, i.e. age, sex, and substance/alcohol use co-morbidities did not appear to influence the choice towards FGAs or SGAs. Despite a lack of evidence, clinicians tend to favour FGA over SGA LAIs in bipolar or personality disorder patients with relevant hostility. Further research is needed to evaluate treatment adherence and clinical effectiveness of these prescriptive patterns

    The Role of Attitudes Toward Medication and Treatment Adherence in the Clinical Response to LAIs: Findings From the STAR Network Depot Study

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    Background: Long-acting injectable (LAI) antipsychotics are efficacious in managing psychotic symptoms in people affected by severe mental disorders, such as schizophrenia and bipolar disorder. The present study aimed to investigate whether attitude toward treatment and treatment adherence represent predictors of symptoms changes over time. Methods: The STAR Network \u201cDepot Study\u201d was a naturalistic, multicenter, observational, prospective study that enrolled people initiating a LAI without restrictions on diagnosis, clinical severity or setting. Participants from 32 Italian centers were assessed at three time points: baseline, 6-month, and 12-month follow-up. Psychopathological symptoms, attitude toward medication and treatment adherence were measured using the Brief Psychiatric Rating Scale (BPRS), the Drug Attitude Inventory (DAI-10) and the Kemp's 7-point scale, respectively. Linear mixed-effects models were used to evaluate whether attitude toward medication and treatment adherence independently predicted symptoms changes over time. Analyses were conducted on the overall sample and then stratified according to the baseline severity (BPRS < 41 or BPRS 65 41). Results: We included 461 participants of which 276 were males. The majority of participants had received a primary diagnosis of a schizophrenia spectrum disorder (71.80%) and initiated a treatment with a second-generation LAI (69.63%). BPRS, DAI-10, and Kemp's scale scores improved over time. Six linear regressions\u2014conducted considering the outcome and predictors at baseline, 6-month, and 12-month follow-up independently\u2014showed that both DAI-10 and Kemp's scale negatively associated with BPRS scores at the three considered time points. Linear mixed-effects models conducted on the overall sample did not show any significant association between attitude toward medication or treatment adherence and changes in psychiatric symptoms over time. However, after stratification according to baseline severity, we found that both DAI-10 and Kemp's scale negatively predicted changes in BPRS scores at 12-month follow-up regardless of baseline severity. The association at 6-month follow-up was confirmed only in the group with moderate or severe symptoms at baseline. Conclusion: Our findings corroborate the importance of improving the quality of relationship between clinicians and patients. Shared decision making and thorough discussions about benefits and side effects may improve the outcome in patients with severe mental disorders
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