166 research outputs found

    New dispatching paradigm in power systems including EV charging stations and dispersed generation: A real test case

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    Electric Vehicles (EVs) are becoming one of the main answers to the decarbonization of the transport sector and Renewable Energy Sources (RES) to the decarbonization of the electricity production sector. Nevertheless, their impact on the electric grids cannot be neglected. New paradigms for the management of the grids where they are connected, which are typically distribution grids in Medium Voltage (MV) and Low Voltage (LV), are necessary. A reform of dispatching rules, including the management of distribution grids and the resources there connected, is in progress in Europe. In this paper, a new paradigm linked to the design of reform is proposed and then tested, in reference to a real distribution grid, operated by the main Italian Distribution System Operator (DSO), e-distribuzione. First, in reference to suitable future scenarios of spread of RES-based power plants and EVs charging stations (EVCS), using Power Flow (PF) models, a check of the operation of the distribution grid, in reference to the usual rules of management, is made. Second, a new dispatching model, involving DSO and the resources connected to its grids, is tested, using an Optimal Power Flow (OPF) algorithm. Results show that the new paradigm of dispatching can effectively be useful for preventing some operation problems of the distribution grids

    EV charging stations and RES-based DG: A centralized approach for smart integration in active distribution grids

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    Renewable Energy Sources based (RES-based) Dispersed Generation (DG) and Electrical Vehicles (EVs) charging systems diffusion is in progress in many Countries around the word. They have huge effects on the distribution grids planning and operation, particularly on MV and LV distribution grids. Many studies on their impact on the power systems are ongoing, proposing different approaches of managing. The present work deals with a real application case of integration of EVs charging stations with ES-based DG. The final task of the integration is to be able to assure the maximum utilization of the distribution grid to which both are connected, without any upgrading action, and in accordance with Distribution System Operators (DSOs) needs. The application of the proposed approach is related to an existent distribution system, owned by edistribuzione, the leading DSO in Italy. Diverse types of EVs supplying stations, with diverse diffusion scenarios, have been assumed for the case study; various Optimal Power Flow (OPF) models, based on diverse objective functions, reflecting DSO necessities, have been applied and tried. The obtained results demonstrate that a centralized management approach by the DSO, could assure the respect of operation limits of the system in the actual asset, delaying or avoiding upgrading engagements and charges

    Mesoglycan for pain control after open excisional HAEMOrrhoidectomy (MeHAEMO). An observational multicentre study on behalf of the Italian Society of Colorectal Surgery (SICCR)

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    Background: Excisional haemorrhoidectomy is the gold standard technique in patients with III and IV degree haemorrhoidal disease (HD). However, it is associated with a significant rate of post-operative pain. The aim of our study was to evaluate the efficacy of mesoglycan in the post-operative period of patients who underwent open excisional diathermy haemorrhoidectomy (OEH). Methods: This was a retrospective multicentre observational study. Three hundred ninety-eight patients from sixteen colorectal referral centres who underwent OEH for III and IV HD were enrolled. All patients were followed-up on the first post-operative day (T1) and after 1 week (T2), 3 weeks (T3) and 6 weeks (T4). BMI, habits, SF-12 questionnaire, VAS at rest (VASs), after defecation (VASd), and after anorectal digital examination (VASe), bleeding and thrombosis, time to surgical wound healing and autonomy were evaluated. Results: In the mesoglycan group, post-operative thrombosis was significantly reduced at T2 (p < 0.05) and T3 (p < 0.005), and all patients experienced less post-operative pain at each time point (p < 0.001 except for VASe T4 p = 0.003). There were no significant differences between the two groups regarding the time to surgical wound healing or post-operative bleeding. There was an early recovery of autonomy in the mesoglycan group in all three follow-up periods (T2 p = 0.016; T3 p = 0.002; T4 p = 0.007). Conclusions: The use of mesoglycan led to a significant reduction in post-operative thrombosis and pain with consequent early resumption of autonomy. Trial registration NCT0448169

    State of the art of immunoassay methods for B-type natriuretic peptides: An update

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    The aim of this review article is to give an update on the state of the art of the immunoassay methods for the measurement of B-type natriuretic peptide (BNP) and its related peptides. Using chromatographic procedures, several studies reported an increasing number of circulating peptides related to BNP in human plasma of patients with heart failure. These peptides may have reduced or even no biological activity. Furthermore, other studies have suggested that, using immunoassays that are considered specific for BNP, the precursor of the peptide hormone, proBNP, constitutes a major portion of the peptide measured in plasma of patients with heart failure. Because BNP immunoassay methods show large (up to 50%) systematic differences in values, the use of identical decision values for all immunoassay methods, as suggested by the most recent international guidelines, seems unreasonable. Since proBNP significantly cross-reacts with all commercial immunoassay methods considered specific for BNP, manufacturers should test and clearly declare the degree of cross-reactivity of glycosylated and non-glycosylated proBNP in their BNP immunoassay methods. Clinicians should take into account that there are large systematic differences between methods when they compare results from different laboratories that use different BNP immunoassays. On the other hand, clinical laboratories should take part in external quality assessment (EQA) programs to evaluate the bias of their method in comparison to other BNP methods. Finally, the authors believe that the development of more specific methods for the active peptide, BNP1–32, should reduce the systematic differences between methods and result in better harmonization of results

    Has VZV epidemiology changed in Italy? Results of a seroprevalence study

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    The aim of the study was to evaluate if and how varicella prevalence has changed in Italy. In particular a seroprevalence study was performed, comparing it to similar surveys conducted in pre-immunization era. During 2013–2014, sera obtained from blood samples taken for diagnostic purposes or routine investigations were collected in collaboration with at least one laboratory/center for each region, following the approval of the Ethics Committee. Data were stratified by sex and age. All samples were processed in a national reference laboratory by an immunoassay with high sensitivity and specificity. Statutory notifications, national hospital discharge database and mortality data related to VZV infection were analyzed as well. A total of 3707 sera were collected and tested. In the studied period both incidence and hospitalization rates decreased and about 5 deaths per year have been registered. The seroprevalence decreased in the first year of life in subjects passively protected by their mother, followed by an increase in the following age classes. The overall antibody prevalence was 84%. The comparison with surveys conducted with the same methodology in 1996–1997 and 2003–2004 showed significant differences in age groups 1–19 y. The study confirms that in Italy VZV infection typically occurs in children. The impact of varicella on Italian population is changing. The comparison between studies performed in different periods shows a significant increase of seropositivity in age class 1–4 years, expression of vaccine interventions already adopted in some regions
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