Sensitivity-Based Model of Low Voltage Distribution Systems with Distributed Energy Resources

A key issue in Low Voltage(LV) distribution systems is to identify strategies for the optimal management and control in the presence of Distributed Energy Resources (DERs). To reduce the number of variables to be monitored and controlled, virtual levels of aggregation, called Virtual Microgrids (VMs), are introduced and identified by using new models of the distribution system. To this aim, this paper, revisiting and improving the approach outlined in a conference paper, presents a sensitivity-based model of an LV distribution system, supplied by a Medium/Low Voltage (MV/LV) substation and composed by several feeders, which is suitable for the optimal management and control of the grid and for VM definition. The main features of the proposed method are: it evaluates the sensitivity coefficients in a closed form; it provides an overview of the sensitivity of the network to the variations of each DER connected to the grid; and it presents a limited computational burden. A comparison of the proposed method with both the exact load flow solutions and a perturb-and-observe method is discussed in a case study. Finally, the method is used to evaluate the impact of the DERs on the nodal voltages of the network

Improving scheduled maintenance by missing data reconstruction: A double-loop Monte Carlo approach

This article describes a Monte Carlo-based approach for reconstructing missing information in a dataset used by General Electric for reliability analysis, which contains data coming from field observations at inspection of gas turbine components. The approach is based on a combination of maximum likelihood estimation technique to estimate the failure model parameters, Fisher information matrix to estimate the confidence intervals on the estimated parameters, and a double-loop Monte Carlo approach to estimate the missing equivalent starts (i.e. data of turbine state without the relative equivalent starts). The proposed methodology reduces the uncertainty in the estimation of the parameters of the turbine. The results of the application of the novel approach to a real industrial dataset are discussed along with a sensitivity analysis for the quantification of the robustness of the methodology to deal with different sizes of datasets

The chimeric ALT-vastus lateralis free flap in reconstruction of advanced BRONJ of the maxilla.

Introduction Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a dangerous complication of bisphosphonates, a class of pharmaceutical agents used in numerous bone disor- ders. No gold standard therapy exists, but recent literature suggests that, in advanced stages, the best results are achieved with aggressive debridement. In this paper, we report our experience of treatment of stage 3 BRONJ of the maxilla with extensive surgical debridement and reconstruction with a chimeric ALT-Vastus lateralis flap. Methods Five selected patients with stage 3 BRONJ underwent partial maxillectomy with dis- ease-free margins followed by immediate reconstruction with a chimeric ALT-Vastus lateralis free flap. Results Only two patients experienced minor complications. All other patients healed unevent- fully within two weeks and donor site morbidity was minimal. Conclusions Our data suggest that aggressive debridement and reconstruction with a chimeric ALT -Vastus lateralis flap is an effective option for the treatment of stage III BRONJ of the maxilla

Do we need more than just powerful blood pressure reductions? New paradigms in end-organ protection

Antihypertensive therapy can lower the risk of cardiovascular morbidity and mortality. Yet, partly because of inadequate dosing, wrong pharmacological choices, and poor patient adherence, hypertension control remains suboptimal in the majority of hypertensive patients. Achieving greater blood pressure control requires a multifaceted approach that raises awareness of hypertension, uses effective therapies, and improves adherence. Particular classes of antihypertensive therapy have beneficial actions beyond blood pressure and studies have evaluated differences in cardiovascular protection among classes. The LIFE and HOPE studies showed between-class differences that may be due to effects other than blood pressure-lowering. In the ONTARGET study, telmisartan and ramipril provided similar cardiovascular protection but adherence was higher with telmisartan, which was better tolerated. This difference in compliance is likely to be important for long-term therapy. The selection of an agent for cardiovascular protection should depend on an appreciation of its composite properties, including any beneficial effects on tolerability and increased patient adherence, as these are likely to be advantageous for the long-term management of hypertension. This review examines the evidence that the effects beyond blood pressure provided by some antihypertensive agents can also lower the risk of cardiovascular, cerebrovascular, and renal events in patients with hypertension

New standards in hypertension and cardiovascular risk management: focus on telmisartan

Blockade of the renin–angiotensin system is an important approach in managing high blood pressure, and has increasingly been shown to affect cardiovascular disease processes mediated by angiotensin II throughout the cardiovascular and renal continua. Telmisartan is an angiotensin II receptor blocker (ARB) displaying unique pharmacologic properties, including a longer half life than any other ARB, that result in large and sustained reductions of blood pressure. In patients with mild-to-moderate hypertension, telmisartan has proved superior to other antihypertensive agents (valsartan, losartan, ramipril, perindopril, and atenolol) in controlling blood pressure particularly towards the end of the dosing interval. There is also clinical evidence that telmisartan reduces left ventricular hypertrophy, reduces arterial stiffness and the recurrence of atrial fibrillation, and confers renoprotection. The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET®) study has demonstrated that telmisartan has similar cardiovascular protective effects to ramipril in a large, high-risk patient population but was better tolerated. The powerful and sustained blood pressure control apparent in clinical trials, together with cardiovascular protection and tolerability demonstrated in ONTARGET® means that telmisartan may be a preferred option for patients with hypertension

TAVI: New trials and registries offer further welcome evidence - U.S. CoreValve, CHOICE, and GARY

The introduction of transcatheter aortic valve implantation (TAVI) has resulted in a paradigm shift in the treatment of patients with severe aortic stenosis. Data from the recent U.S CoreValve Trial suggest, for the first time, that TAVI is associated with a significantly higher rate of survival at one year compared to surgical aortic valve replacement (SAVR) in the treatment of high-risk patients affected by severe aortic stenosis. The present review discusses this study and the current evidence about TAVI, for the treatment of severe aortic stenosis, from major trials and real world registries

A case of massive subcutaneous emphysema and transient ischemic attack due to argon plasma coagulation following endoscopic pilonidal sinus treatment

Pilonidalsinusisasmallholeaffectingtheskinandsubcutaneoustissue,whichusuallycontainshairandskindebris,resultinginthecreationoftheso-calledpilonidalcyst.Theendoscopicpilonidalsinustreatment(EPSiT)isaminimallyinvasiveprocedureconsistingoftheremovalofhairsandcauterizationofthecavityunderdirectendoscopicvision.Inourinstitution,weusedtoendthisprocedurewithargonplasmacoagulation(APC).Here,wediscussacaseof22-year-oldmanaffectedbypilonidaldisease,whodevelopedamassivesubcutaneousemphysemaandsuspectedtransientischemicattacksecondarytogasreabsorptionafteranEPSiTinwhichAPCwassedforthecoagulation

Trend of estimated glomerular flitration rate in a large cohort of HIV mother-to -child infected patients, an observational multicenter study from 2010 to 2018

Background: People vertically infected with HIV (PVI-HIV) are a special population, due to exposition since birth to HIV and antiretroviral therapy (ART). Among ART, Tenofovir disoproxil fumarate (TDF) was widely used in recent years, but there are few data on safety in these patients; in particular, data about estimated glomerular filtration rate (eGFR) trend in this population. Aim of our study is to evaluate eGFR trend in a multicentre cohort of PVI-HIV exposed to TDF

Effectiveness of equine-assisted activities and therapies for improving adaptive behavior and motor function in autism spectrum disorder

Equine-assisted activities and therapies (EAAT) have been suggested to improve adaptive behavior, and possibly motor function, in autism spectrum disorder (ASD). This study investigated the effects of EAAT on adaptive behavior and motor function in 15 children with ASD (13 males) aged 7-15 years as well as the impact of EAAT on the magnitude of stress in the parent-child system and the evolution in the child interaction with both the trained therapist and the therapeutic animal through the 20 weekly sessions of EAAT. EAAT were associated with greater adaptive behavior and coordination (all p 64 0.01) as well as a progressive improvement in the child's abilities to respond to the increasing complexity of such form of positive behavioral support (all p < 0.001). However, EAAT did not prove to be effective in reducing parental distress. Collectively, preliminary evidence presented here may have important public health implications and gives reason to hope that EAAT could possibly be an effective option in ASD, warranting further investigation of its potential benefits in clinical trials among larger samples