124 research outputs found

    Numerical and Experimental Investigation of the Flow over a Car Prototype for the Shell Eco Marathon

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    The Eco-Marathon is a challenge organized by Shell in which student teams compete in designing energy-efficient vehicles. The event spark debate about the future of mobility and inspire engineers to push the boundaries of fuel efficiency. The aim of the present work consists of the numerical and experimental investigation of the aerodynamic performance of a Shell Eco Marathon prototype designed by a group of students of the University of Cassino, Italy. The car design has been provided by means of detailed 3D CFD modelling with Comsol Multiphysics¼. The numerical tool has been validated against experiments conducted at the Laboratory of Industrial Measurements (LaMI) of the University of Cassino. In particular, a scale model of the car has been investigated in an open chamber wind tunnel by means of the Particle Image Velocimetry (PIV) technique, for different free stream velocities within the range 11 – 23 m/s. Measurements have been associated to a proper uncertainty analysis. The experimental data has been compared to numerical results obtained employing different turbulence models and the validated numerical tool has been applied to the simulation of the full-scale car model, allowing to analyse the wake flow structures, and estimate the overall drag coefficient

    Uveitis and other ocular complications following covid-19 vaccination

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    Coronavirus disease 2019 (COVID-19) vaccines can cause transient local and systemic post-vaccination reactions. The aim of this study was to report uveitis and other ocular complications following COVID-19 vaccination. The study included 42 eyes of 34 patients (20 females, 14 males), with a mean age of 49.8 years (range 18–83 years). The cases reported were three herpetic keratitis, two anterior scleritis, five anterior uveitis (AU), three toxoplasma retinochoroiditis, two Vogt-Koyanagi-Harada (VKH) disease reactivations, two pars planitis, two retinal vasculitis, one bilateral panuveitis in new-onset Behçet’s disease, three multiple evanescent white dot syndromes (MEWDS), one acute macular neuroretinopathy (AMN), five retinal vein occlusions (RVO), one non-arteritic ischemic optic neuropathy (NAION), three activations of quiescent choroidal neovascularization (CNV) secondary to myopia or uveitis, and one central serous chorioretinopathy (CSCR). Mean time between vaccination and ocular complication onset was 9.4 days (range 1–30 days). Twenty-three cases occurred after Pfizer-BioNTech vaccination (BNT162b2 mRNA), 7 after Oxford-AstraZeneca vaccine (ChAdOx1 nCoV-19), 3 after ModernaTX vaccination (mRNA-1273), and 1 after Janssen Johnson & Johnson vaccine (Ad26.COV2). Uveitis and other ocular complications may develop after the administration of COVID-19 vaccine

    Biological and methodological factors affecting VO2max response variability to endurance training and the influence of exercise intensity prescription

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    © 2021 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society. This is an open access article under the terms of the Creative Commons Attribution License. https://creativecommons.org/licenses/by/4.0/Changes in cardiorespiratory fitness (CRF) in response to endurance training (ET) exhibit large variations, possibly due to a multitude of biological and methodological factors. It is acknowledged that ~20% of individuals may not achieve meaningful increases in CRF in response to ET. Genetics, the most potent biological contributor, has been shown to explain ~50% of response variability, whilst age, sex, and baseline CRF appear to explain a smaller proportion. Methodological factors represent the characteristics of the ET itself including the type, volume, and intensity of exercise, as well as the method used to prescribe and control exercise intensity. Notably, methodological factors are modifiable and, upon manipulation, alter response rates to ET, eliciting increases in CRF regardless of an individual’s biological predisposition. Particularly, prescribing exercise intensity relative to a physiological threshold (e.g. ventilatory threshold) is shown to increase CRF response rates compared to when intensity is anchored relative to a maximum physiological value (e.g. maximum heart rate). It is, however, uncertain whether the increased response rates are primarily attributable to reduced response variability, greater mean changes in CRF, or both. Future research is warranted to elucidate whether more homogenous chronic adaptations manifest over time among individuals, as a result of exposure to more homogenous exercise stimuli elicited by threshold-based practices.Peer reviewe

    Evaluation of BAFF, APRIL and CD40L in ocrelizumab-treated pwMS and infectious risk

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    Simple Summary Since B cells have been linked to multiple sclerosis (MS) and its progression as well as T cells, the second-generation anti-CD20 recombinant humanized monoclonal antibody ocrelizumab has been approved for MS treatment. Although ocrelizumab efficiently depletes B cells in peripheral blood, some B cells and CD20 negative plasma cells persist in lymphatic organs, and their survival is regulated by the B-cell-activating factor (BAFF)/a proliferation-inducing ligand (APRIL) system. Moreover, ocrelizumab may result in higher infectious risk. Herein, we investigated plasma BAFF, APRIL and CD40L levels and their relationship with infectious risk in ocrelizumab-treated people with (pw) MS at baseline, at 6 months and at 12 months after starting the treatment, comparing the above-mentioned findings with a control group. At baseline, plasma levels of all three cytokines were higher compared to the control group. In pwMS, the longitudinal assessment showed a significant increase in plasma BAFF levels and a significant reduction in plasma APRIL and CD40L. Moreover, when stratifying pwMS according to the onset of an infectious event during the 12-month follow-up period, significantly higher plasma BAFF levels were found at all time-points in the group with an infectious event than in the group without an infectious event. Hence, BAFF may have a role as a marker of immune dysfunction and infectious risk. Background: The anti-CD20 monoclonal antibody ocrelizumab has been widely employed in the treatment of people with multiple sclerosis (pwMS). However, its B-cell-depleting effect may induce a higher risk of infectious events and alterations in the secretion of B-cell-activating factors, such as BAFF, APRIL and CD40L. Methods: The aim of this study was to investigate plasma BAFF, APRIL and CD40L levels and their relationship with infectious risk in ocrelizumab-treated pwMS at baseline (T0), at 6 months (T6) and at 12 months (T12) after starting the treatment. As a control group, healthy donors (HD) were enrolled too. Results: A total of 38 pwMS and 26 HD were enrolled. At baseline, pwMS showed higher plasma BAFF (p < 0.0001), APRIL (p = 0.0223) and CD40L (p < 0.0001) levels compared to HD. Compared to T0, plasma BAFF levels were significantly increased at both T6 and T12 (p < 0.0001 and p < 0.0001, respectively). Whereas plasma APRIL and CD40L levels were decreased at T12 (p = 0.0003 and p < 0.0001, respectively). When stratifying pwMS according to the development of an infectious event during the 12-month follow-up period in two groups-with (14) and without an infectious event (24)-higher plasma BAFF levels were observed at all time-points; significantly, in the group with an infectious event compared to the group without an infectious event (T0: p < 0.0001, T6: p = 0.0056 and T12: p = 0.0400). Conclusions: BAFF may have a role as a marker of immune dysfunction and of infectious risk

    Natalizumab affects T-cell phenotype in multiple sclerosis: implications for JCV reactivation

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    The anti-CD49d monoclonal antibody natalizumab is currently an effective therapy against the relapsing-remitting form of multiple sclerosis (RRMS). Natalizumab therapeutic efficacy is limited by the reactivation of the John Cunningham polyomavirus (JCV) and development of progressive multifocal leukoencephalopathy (PML). To correlate natalizumab-induced phenotypic modifications of peripheral blood T-lymphocytes with JCV reactivation, JCV-specific antibodies (serum), JCV-DNA (blood and urine), CD49d expression and relative abundance of peripheral blood T-lymphocyte subsets were longitudinally assessed in 26 natalizumab-treated RRMS patients. Statistical analyses were performed using GraphPad Prism and R. Natalizumab treatment reduced CD49d expression on memory and effector subsets of peripheral blood T-lymphocytes. Moreover, accumulation of peripheral blood CD8+ memory and effector cells was observed after 12 and 24 months of treatment. CD4+ and CD8+ T-lymphocyte immune-activation was increased after 24 months of treatment. Higher percentages of CD8+ effectors were observed in subjects with detectable JCV-DNA. Natalizumab reduces CD49d expression on CD8+ T-lymphocyte memory and effector subsets, limiting their migration to the central nervous system and determining their accumulation in peripheral blood. Impairment of central nervous system immune surveillance and reactivation of latent JCV, can explain the increased risk of PML development in natalizumab-treated RRMS subjects

    Cataract surgery with intraocular lens implantation in juvenile idiopathic arthritis-associated uveitis: Outcomes in the era of biological therapy

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    This study compared the outcomes of cataract surgery with intraocular lens (IOL) implantation in patients with juvenile idiopathic arthritis (JIA)-associated chronic anterior uveitis treated with antimetabolite drugs and systemic corticosteroids (Non-Biological Group) versus patients treated with antimetabolites and biological drugs (Biological Group). A cohort of patients with cataract in JIA-associated uveitis undergoing phacoemulsification with IOL implantation was retrospectively evaluated. The main outcome was a change in corrected distance visual acuity (CDVA) in the two groups. Ocular and systemic complications were also recorded. The data were collected preoperatively and at 1, 12, and 48 months after surgery. Thirty-two eyes of 24 children were included: 10 eyes in the Non-Biological Group and 22 eyes in the Biological Group. The mean CDVA improved from 1.19 ± 0.72 logMAR preoperatively to 0.98 ± 0.97 logMAR at 48 months (p = 0.45) in the Non-Biological Group and from 1.55 ± 0.91 logMAR preoperatively to 0.57 ± 0.83 logMAR at 48 months (p = 0.001) in the Biological Group. The postoperative complications, including synechiae, cyclitic membrane, IOL explantation, glaucoma, and macular edema, were not statistically different between the two groups. An immunosuppressive treatment with biological drugs can improve the visual outcome after cataract surgery in patients with JIA-associated uveitis, but it does not significantly reduce postoperative ocular complications

    The functional trait spectrum of European temperate grasslands

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    Questions: What is the functional trait variation of European temperate grasslands and how does this reflect global patterns of plant form and function? Do habitat specialists show trait differentiation across habitat types?. Location: Europe. Methods: We compiled 18 regeneration and non-regeneration traits for a continental species pool consisting of 645 species frequent in five grassland types. These grassland types are widely distributed in Europe but differentiated by altitude, soil bedrock and traditional long-term management and disturbance regimes. We evaluated the multivariate trait space of this entire species pool and compared multi-trait variation and mean trait values of habitat specialists grouped by grassland type. Results: The first dimension of the trait space accounted for 23% of variation and reflected a gradient between fast-growing and slow-growing plants. Plant height and SLA contributed to both the first and second ordination axes. Regeneration traits mainly contributed to the second and following dimensions to explain 56% of variation across the first five axes. Habitat specialists showed functional differences between grassland types mainly through non-regeneration traits. Conclusions: The trait spectrum of plants dominating European temperate grasslands is primarily explained by growth strategies which are analogous to the trait variation observed at the global scale, and secondly by regeneration strategies. Functional differentiation of habitat specialists across grassland types is mainly related to environmental filtering linked with altitude and disturbance. This filtering pattern is mainly observed in non-regeneration traits, while most regeneration traits demonstrate multiple strategies within the same habitat type.EL, BJA, MTI, AM, PI and CB acknowledge the research leading to these results has received funding from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007–2013 under REA grant agreement no. 607785, as a part of the NAtive Seed Science TEchnology and Conservation (NASSTEC) Initial Training Network (ITN). BJA was further funded by the Marie Curie Clarín‐COFUND program of the Principality of Asturias and the European Union (ACB17‐26). BJA and HB acknowledge support from the German Centre for Integrative Biodiversity Research (iDiv) Halle–Jena–Leipzig funded by the German Research Foundation (DFTG FZT 118) through the sPlot research platform. PI acknowledges support from the Rural & Environment Science & Analytical Services Division of the Scottish Government. KÖ thanks RO1567‐IBB03/2018 for financial support
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