118 research outputs found

    A Model of DC-DC Converter with Switched-Capacitor Structure for Electric Vehicle Applications

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    In this paper, a DC-DC converter with an innovative topology for automotive applications is proposed. The goal of the presented power converter is the electrical storage system management of an electric vehicle (EV). The presented converter is specifically compliant with a 400 V battery, which represents the high-voltage primary source of the system. This topology is also able to act as a bidirectional power converter, so that in this case, the output section is an active stage, which is able to provide power as, for example, in the case of a low-voltage battery or a supercapacitor. The proposed topology can behave either in step-down or in step-up mode, presenting in both cases a high gain between the input and output voltage. Simulation results concerning the proposed converter, demonstrating the early feasibility of the system, were obtained in a PowerSIM environment and are described in this paper

    Dynamic reconfiguration of electrical connections for partially shaded PV modules: Technical and economical performances of an Arduino-based prototype

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    The partial shading phenomenon is a well known problem of photovoltaic plants. Partial shading leads to undesirable effects such the electrical mismatch, the generation of hot spots, and generally the decrease of production of electric energy. To mitigate the last effect, a dynamic reconfiguration of the electrical connections between modules was taken into account. In this paper, starting from an already developed system for a small-scale photovoltaic plant reconfiguration, the study of the economical benefits of the employment of a reconfigurator are traced. Five different incentive policies of diverse Countries have been considered to evaluate the increase of Net Present Value of system with and without a reconfigurator

    Recycling of a multilayer barrier food packaging through the use of a nanofiller: Effect of post-consumer plastic bag conditions

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    Barrier food packaging films result very difficult to recycle since they are multilayer films composed by at least two different materials. In this context, aim of this study was to assess the use of a nanofiller for the mechanical recycling of multilayer barrier plastic bags used for food vacuum packaging. In particular, graphene nanoplatelets (GnPs) were used as nanofiller studying the effect of their concentration on the properties of the nanocomposites obtained by using polyamide (PA)/polyethylene (PE) bags as polymeric matrix. Moreover, the effect of plastic bags life conditions on the nanocomposite properties were evaluated by exposing the multilayer films to accelerated weathering or to contact with a fatty food simulant (olive oil). The results indicated that the incorporation of GnPs led to an enhancement of the morphology of the polymer blends, consequently resulting in nanocomposites with increased stiffness without a drastic reduction in ductility. The nanocomposites produced using post-consumer bags exhibited lower properties compared to materials produced using pre-consumer bags. However, even in this case, the addition of GnPs contributed to an improvement in the properties demonstrating that the use of this nanofiller can be a viable method to recycle multilayer packaging

    Experimental study on B-spline-based modulation schemes applied in multilevel inverters for electric drive applications

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    This work presents the design, simulation, and experimental validation of new B-Spline-based modulation techniques applied to a Multilevel Power Inverter (MPI), particularly focusing the attention on the harmonic content of the output voltages of the inverter. Simulation and experimental results are proposed and discussed, mainly describing the potential benefits, such as the increase of the multi-level operation of the converter, and drawbacks (low-order harmonics) related to the adoption of B-Spline functions for multilevel inverters applied in the field of electrical drives

    Randomized placebo-controlled trial comparing desloratadine and montelukast in monotherapy and desloratadine plus montelukast in combined therapy for chronic idiopathic urticaria

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    BACKGROUND: H 1 -receptor antagonists are considered to be particularly effective in reducing pruritus, and they are therefore recommended as first-line treatment in patients with chronic idiopathic urticaria (CIU). Recently, antileukotriene receptors have been used in patients with CIU, either administered as monotherapy or combined with H 1 -receptor antagonists. OBJECTIVE: We compared the clinical efficacy of 5 mg of desloratadine administered once daily either as monotherapy or combined with a leukotriene antagonist, 10 mg of montelukast daily, and 10 mg of montelukast administered daily as monotherapy for the treatment of patients affected by CIU with placebo. METHODS: One hundred sixty patients aged 18 to 69 years (mean +/- SD, 43.9 +/- 13.4 years) with a history of moderate CIU were selected. A randomized, double-blind, double-dummy, placebo-controlled, parallel-group study design was used. Patients were treated with 5 mg of desloratadine once daily (n = 40), 10 mg of montelukast once daily (n = 40), 5 mg of desloratadine (n = 40) in the morning plus montelukast in the evening, or matched placebo (n = 40). Assessment of treatment efficacy was based on scores of daily cutaneous symptoms evaluated reflectively and instantaneously. RESULTS: Only the group treated with desloratadine as monotherapy or as combined therapy concluded the whole study. Twenty-seven of the 40 patients in the montelukast group and 35 of the 40 patients in the placebo group discontinued the treatment. As reflective evaluation, all groups showed significant differences compared with the placebo group in terms of total symptom score, number of hives, and size of largest hive. In addition to the pruritus, only the groups treated with desloratadine as monotherapy or combined therapy showed significant differences compared with those receiving placebo, whereas there were no differences between the montelukast and placebo groups. Finally, no differences were found between the desloratadine group and the desloratadine plus montelukast group. The instantaneous evaluation demonstrated similar results regarding the desloratadine group and the desloratadine plus montelukast group versus the placebo group, whereas there were no significant differences between the group treated with montelukast alone and the placebo group for pruritus and size of largest hive. No differences were found between the group treated with desloratadine alone and the desloratadine plus montelukast group. CONCLUSIONS: The results of this comparative study demonstrate that desloratadine is highly effective for the treatment of patients affected by CIU. In addition, the regular combined therapy of desloratadine plus montelukast does not seem to offer a substantial advantage with respect to desloratadine as monotherapy in patients affected by moderate CIU

    NMR Metabolomics for Stem Cell type discrimination

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    Cell metabolism is a key determinant factor for the pluripotency and fate commitment of Stem Cells (SCs) during development, ageing, pathological onset and progression. We derived and cultured selected subpopulations of rodent fetal, postnatal, adult Neural SCs (NSCs) and postnatal glial progenitors, Olfactory Ensheathing Cells (OECs), respectively from the subventricular zone (SVZ) and the olfactory bulb (OB). Cell lysates were analyzed by proton Nuclear Magnetic Resonance (1H-NMR) spectroscopy leading to metabolites identification and quantitation. Subsequent multivariate analysis of NMR data by Principal Component Analysis (PCA), and Partial Least Square Discriminant Analysis (PLS-DA) allowed data reduction and cluster analysis. This strategy ensures the definition of specific features in the metabolic content of phenotypically similar SCs sharing a common developmental origin. The metabolic fingerprints for selective metabolites or for the whole spectra demonstrated enhanced peculiarities among cell types. The key result of our work is a neat divergence between OECs and the remaining NSC cells. We also show that statistically significant differences for selective metabolites characterizes NSCs of different ages. Finally, the retrived metabolome in cell cultures correlates to the physiological SC features, thus allowing an integrated bioengineering approach for biologic fingerprints able to dissect the (neural) SC molecular specificitie

    Challenges for the Goal of 100% Renewable Energy Sources to Fit the Green Transition

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    The increasing penetration of Renewable Energy (RE) into the electrical market is desirable in terms of sustainability. Nevertheless, it is a challenge that all the interested actors shall address from both the technical and economical points of view. This paper provides an overview of the main challenges and solutions towards the technological transition to an electrical system with 100% renewable energy sources in terms of innovations and operative limits of the traditional systems. These innovative paradigms will also address the social impact and government policies

    Randomized placebo-controlled trial comparing fluticasone aqueous nasal spray in mono-therapy, fluticasone plus cetirizine, fluticasone plus montelukast and cetirizine plus montelukast for seasonal allergic rhinitis

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    BACKGROUND: Corticosteroids are considered to be particularly effective in reducing nasal congestion and are therefore recommended as first-line treatment in allergic rhinitis patients with moderate to severe and/or persistent symptoms. OBJECTIVE: We compared the clinical efficacy of fluticasone propionate aqueous nasal spray (FPANS) 200 microg given once daily, administered in mono-therapy or combined therapy with a H1 receptor antagonist (cetirizine, CTZ) or with a leukotriene antagonist (montelukast, MSK), and the combined therapy of CTZ plus MSK in the treatment of patients affected by allergic rhinitis to Parietaria during natural pollen exposure. In addition, we examined the effect of the treatment on eosinophil counts and eosinophil cationic protein (ECP) in nasal lavage performed at beginning of season, during season and at the end of the season. METHODS: One hundred patients aged 12-50 years (mean+/-SD 31.8+/-9.6) with a history of moderate to severe Parietaria pollen-induced seasonal allergic rhinitis were selected. A randomized, double-blind, double dummy, placebo (PLA)-controlled, parallel-group study design was used. Patients were treated FPANS 200 microg once daily (n=20) or with FPANS 200 microg once daily, plus CTZ (10 mg) in the morning (n=20), or with FPANS 200 microg once daily, plus MSK (10 mg) in the evening (n=20) or with CTZ (10 mg) in the morning plus MSK in the evening (n=20) or matched PLA (n=20). Assessment of efficacy was based on scores of daily nasal symptoms and on eosinophil counts and ECP in nasal lavage. RESULTS: All treatments showed significant differences (P<0.001) compared with PLA in terms of total symptom, rhinorrhea, sneezing and nasal itching scores. Concerning nasal congestion on waking and daily only the groups treated with FPANS in mono-therapy or in combined therapy showed significant differences compared with PLA. Comparing the group treated with FPANS alone and the groups treated with FPANS plus CTZ, we found significant differences for total symptom score (P=0.04) and for nasal itching (P=0.003). The comparison between FPANS plus CTZ and FPANS plus MSK showed significant difference for nasal itching (P=0.003). Finally, there were significant differences between the group treated with FPANS and the group treated with CTZ plus MSK for total symptom score (P=0.009), for nasal congestion on waking (P<0.001) and nasal congestion daily (P<0.001). Also the comparisons between the group treated with FPANS plus CTZ and the group treated with CTZ plus MSK demonstrated significant differences (P<0.001) for total symptom, for nasal congestion on waking and for nasal congestion on daily, for rhinorrhea (P=0.04) and for nasal itching (P=0.003) scores. Concerning the comparison between the group treated with FPANS plus MSK and the group treated with CTZ plus MSK we found significant differences for total symptom score (P=0.005), for nasal congestion on waking (P<0.001) and for nasal congestion on daily (P<0.001). No other differences were observed between the groups. Concerning blood eosinophil counts, significant differences were found between the treatments with FPANS in mono-therapy or in combined therapy with PLA group during and at the end of the season (P=0.0003 and P<0.0001, respectively). Concerning eosinophils and ECP in nasal lavage, all treatments showed significant differences (P<0.001) compared with PLA. Besides, there were significant differences (P<0.001) between the groups treated with FPANS alone or in combined therapy and the group treated with CTZ plus MSK. CONCLUSION: The results of this comparative study demonstrate that FPANS is highly effective for treating patients affected by allergic rhinitis, with efficacy exceeding that of CTZ plus MSK in combined therapy. In addition, the regular combined therapy of FPANS plus CTZ or plus MSK would not seem to offer substantial advantage with respect to FPANS in mono-therapy in patients affected by seasonal allergic rhinitis

    Late-onset Parkinsonism in NFκB/c-Rel-deficient mice.

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    Activation of the nuclear factor \u3baB/c-Rel can increase neuronal resilience to pathological noxae by regulating the expression of pro-survival manganese superoxide dismutase (MnSOD, now known as SOD2) and Bcl-xL genes. We show here that c-Rel-deficient (c-rel(-/-)) mice developed a Parkinson's disease-like neuropathology with ageing. At 18 months of age, c-rel(-/-) mice exhibited a significant loss of dopaminergic neurons in the substantia nigra pars compacta, as assessed by tyrosine hydroxylase-immunoreactivity and Nissl staining. Nigral degeneration was accompanied by a significant loss of dopaminergic terminals and a significant reduction of dopamine and homovanillic acid levels in the striatum. Mice deficient of the c-Rel factor exhibited a marked immunoreactivity for fibrillary \u3b1-synuclein in the substantia nigra pars compacta as well as increased expression of divalent metal transporter 1 (DMT1) and iron staining in both the substantia nigra pars compacta and striatum. Aged c-rel(-/-) mouse brain were characterized by increased microglial reactivity in the basal ganglia, but no astrocytic reaction. In addition, c-rel(-/-) mice showed age-dependent deficits in locomotor and total activity and various gait-related deficits during a catwalk analysis that were reminiscent of bradykinesia and muscle rigidity. Both locomotor and gait-related deficits recovered in c-rel(-/-) mice treated with l-3,4-dihydroxyphenylalanine. These data suggest that c-Rel may act as a regulator of the substantia nigra pars compacta resilience to ageing and that aged c-rel(-/-) mice may be a suitable model of Parkinson's disease
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