Decentralized Voltage Optimization Based on the Auxiliary Problem Principle in Distribution Networks with DERs

This paper addresses the problem of optimizing the voltage profile of radially-operated distribution systems by acting on the active and reactive powers provided by distributed energy resources (DERs). A novel voltage optimization procedure is proposed by adopting a decentralized control strategy. To this aim, a centralized voltage optimization problem (VOP), minimizing the distance of all the nodal voltages from their reference values, is firstly formulated as a strictly-convex quadratic program. Then, the centralized VOP is rewritten by partitioning the network into voltage control zones (VCZs) with pilot nodes. To overcome the lack of strictly convexity determined by the reduction to the pilot nodes, the dual centralized VOP working on the augmented Lagrangian function is reformulated and iteratively solved by the method of multipliers. Finally, a fully-distributed VOP solution is obtained by applying a distributed algorithm based on the auxiliary problem principle, which allows for solving in each VCZ a quadratic programming problem of small dimension and to drive the VCZ solutions toward the overall optimum by an iterative coordination process that requires to exchange among the VCZs only scalar values. The effectiveness and feasibility of the proposed method have been demonstrated via numerical tests on the IEEE 123-bus system

Experimental investigation on the influence of the aspect ratio on the in-plane/out-of-plane interaction for masonry infills in RC frames

Abstract The analysis of the behaviour of masonry infills under out-of-plane (OOP) and in-plane (IP) loading is paramount to correctly assess the seismic performance of reinforced concrete (RC) frames. A very important issue about this topic is certainly the IP/OOP interaction, namely the analysis of how the IP damage, which affects infills during earthquakes, can influence their OOP behaviour (and vice-versa). Some studies about this topic were developed in the last years; nevertheless, only a dozen of tests currently exists in the literature to experimentally explore this key issue. This work first presents an experimental campaign carried out on square infill walls in RC frames to investigate about the OOP behaviour of the masonry infills, and about the IP/OOP interaction. On the whole, four specimens have been tested under OOP monotonic loading. Three of them have been first damaged under cyclic IP actions, with different extent; the remaining one, used as a reference, was tested under OOP loading only. The experimental campaign is described in detail in terms of specimens' characteristics, material properties, adopted setup and instrumentation layout. The experimental results are analysed in terms of IP and OOP force-displacement responses, vertical arch strength contribution evolutions, and damage state evolutions, and compared with prediction proposals from the literature. Then, the influence of the infill aspect ratio (width (w)-to-height (h) ratio) on the IP/OOP interaction is investigated by means of the comparison between data presented herein (collected on infills with w/h = 1) and a companion experimental campaign previously performed on nominally identical infills except that for the aspect ratio of the specimens (in that case, higher than the unit). It has been observed that under given IP drift levels, square infills presented lower IP damage levels with respect to rectangular infills (with w/h > 1), thus generally producing a less pronounced detrimental effect of the IP imposed drift on the OOP strength. Nevertheless, none of the predictions from literature takes into account the role of the aspect ratio on the IP/OOP interaction, generally resulting in conservative predictions, to be improved in future works

Experimental analysis of Textile Reinforced Mortars strengthening strategies against the out-of-plane collapse of masonry infill walls

Out-of-plane (OOP) collapse of masonry infill panels in existing reinforced concrete (RC) buildings due to seismic events is a key issue for life safety and seismic economic loss estimation. Few studies in the literature deal with this topic and, above all, with possible strengthening strategies against the OOP collapse. This work presents the main results of an experimental campaign about different strengthening solutions to mitigate the OOP collapse of masonry infills in RC buildings. The investigated strengthening techniques were based on the application of a thin mortar plaster and fiber-reinforced polymer nets with different connection typologies with the surrounding RC frame. The specimens were realized with traditional horizontal hollow clay bricks and were tested through the application of a semi-cyclic OOP displacement pattern by means of uniformly distributed small pneumatic jacks. Tests data and results are presented and commented in terms of OOP force-displacement responses and damage evolution. Details about the effectiveness of each retrofitting solution are provided and compared to support the selection of the best strategy for future applications

Outcome of Very Late Relapse in Patients with Hodgkin's Lymphomas

Recurrences of Hodgkin's Lymphoma (HL) 5 years after the initial therapy are rare. The aim of this study is to report a single centre experience of the clinical characteristics, outcome, and toxicity of pts who experienced very late relapses, defined as relapses that occurred 5 or more years after the achievement of first complete remission. Of 532 consecutive pts with classical HL treated at our Institute from 1985 to 1999, 452 pts (85%) achieved a complete remission. Relapse occurred in 151 pts: 135 (29.8%) within 5 years and 16 over 5 years (3.5%, very late relapses). Very late relapses occurred after a median disease-free interval of 7 years (range: 5–18). Salvage treatment induced complete remission in 14 pts (87.5%). At a median of 4 years after therapy for very late relapse, 10 pts (63%) are still alive and free of disease and 6 (37%) died (1 from progressive HL, 1 from cardiac disease, 1 from thromboembolic disease, 1 from HCV reactivation, and 2 from bacterial infection). The probability of failure-free survival at 5 years was 75%. The majority of deaths are due to treatment-related complications. Therapy regimens for very late relapse HL are warranted to minimize complications

Seismic Loss Estimation in Pre-1970 Residential RC Buildings: The Role of Infills and Services in Low–Mid-Rise Case Studies

The lessons learned after recent earthquakes have highlighted the key role played by infills and services in damage and loss of Reinforced Concrete (RC) buildings. Their influence in seismic performance and loss estimation of selected RC building case studies is thoroughly analyzed here. The case study selection aims to be representative of existing buildings built in Italy before 1970, and covers a different number of stories and design typologies. The seismic responses of the case-study buildings are numerically analyzed by means of non-linear static pushover analysis (PO) considering a lumped plasticity approach with a quadri-linear flexural response for beam/column elements (properly calibrated for RC elements reinforced with plain bars) and a tri-linear compressive-only axial response with diagonal concentric struts for infill panels (empirically derived from experimental data on hollow clay masonry walls). Economic loss estimation is carried out via a component-based methodology that relies on the main repairing activities and resultant costs required for the refurbishment of infills and services for different damage levels. Accordingly, a damage analysis is performed herein, given the intensity measure, based on a comparison between Interstory drift demand from PO analysis and drift-based fragility functions specific for masonry infills. Loss curves, relating the total building repair cost to peak ground acceleration (PGA), are presented and compared for the analyzed case study buildings to show their trends and quantify the incidence of infills and services with respect to the reconstruction cost. A comparison between these outcomes and those recently found in the literature emphasizes the robustness of the considered approach and the reliability of the hypotheses about damage and loss assessment

factors underlying the development of chronic temporal lobe epilepsy in autoimmune encephalitis

Abstract Purpose Limbic encephalitis (LE) is an autoimmune condition characterized by amnestic syndrome, psychiatric features and seizures. Early diagnosis and prompt treatment are crucial to avoid long-term sequelae, including psycho-cognitive deficits and persisting seizures. The aim of our study was to analyze the characteristics of 33 LE patients in order to identify possible prognostic factors associated with the development of chronic epilepsy. Methods This is a retrospective cohort study including adult patients diagnosed with LE in the period 2010–2017 and followed up for ≥12 months. Demographics, seizure semiology, EEG pattern, MRI features, CSF/serum findings were reviewed. Results All 33 LE patients (19 M/14F, mean age 61.2 years) presented seizures. Thirty subjects had memory deficits; 22 presented behavioural/mood disorders. Serum and/or CSF auto-antibodies were detected in 12 patients. In 31 subjects brain MRI at onset showed typical alterations involving temporal lobes. All patients received immunotherapy. At follow-up, 13/33 had developed chronic epilepsy; predisposing factors included delay in diagnosis (p = .009), low seizure frequency at onset (p = .02), absence of amnestic syndrome (p = .02) and absence/rarity of inter-ictal epileptic discharges on EEG (p = .06). Conclusions LE with paucisymptomatic electro-clinical presentation seemed to be associated to chronic epilepsy more than LE presenting with definite and severe "limbic syndrome"

Tsunami risk communication and management: Contemporary gaps and challenges

Very large tsunamis are associated with low probabilities of occurrence. In many parts of the world, these events have usually occurred in a distant time in the past. As a result, there is low risk perception and a lack of collective memories, making tsunami risk communication both challenging and complex. Furthermore, immense challenges lie ahead as population and risk exposure continue to increase in coastal areas. Through the last decades, tsunamis have caught coastal populations off-guard, providing evidence of lack of preparedness. Recent tsunamis, such as the Indian Ocean Tsunami in 2004, 2011 Tohoku and 2018 Palu, have shaped the way tsunami risk is perceived and acted upon. Based on lessons learned from a selection of past tsunami events, this paper aims to review the existing body of knowledge and the current challenges in tsunami risk communication, and to identify the gaps in the tsunami risk management methodologies. The important lessons provided by the past events call for strengthening community resilience and improvement in risk-informed actions and policy measures. This paper shows that research efforts related to tsunami risk communication remain fragmented. The analysis of tsunami risk together with a thorough understanding of risk communication gaps and challenges is indispensable towards developing and deploying comprehensive disaster risk reduction measures. Moving from a broad and interdisciplinary perspective, the paper suggests that probabilistic hazard and risk assessments could potentially contribute towards better science communication and improved planning and implementation of risk mitigation measures

Quality of care provided by Multiple Sclerosis Centers during Covid-19 pandemic: Results of an Italian multicenter patient-centered survey

Background: Covid-19 pandemic impacted on management of people with Multiple Sclerosis (pwMS). Level of satisfaction of pwMS regarding the care received by the staff of Multiple Sclerosis Centers (MSCs) during the pandemic was not fully investigated. In a large patient-centered multicenter study, the therapeutic adherence and quality of care of MSCs was assessed. Methods: In April-May 2021, an online survey was widespread by 16 Italian MSCs. Frequencies, percentages and/or means and standard deviations were calculated to describe the sample. ANOVAs were performed to evaluate the effect of sociodemographic and clinical variables on overall pwMS' rating of MSC assistance. Results: 1670 pwMS completed the survey (67.3% women). During the pandemic, 88% did not change their disease modifying therapy schedule, and 89.1% reached their MSCs with no or little difficulties. Even if only 1.3% of participants underwent a tele-health follow-up visit with their MSC staff, the 80.1% believed that tele-health services should be improved regardless of pandemic. 92% of participants were satisfied of how their MSC took charge of their needs; ANOVAs revealed an effect of disease duration on pwMS' level of satisfaction on MSCs management during the pandemic. Conclusions: The results revealed an efficient MSCs response to Covid-19 pandemic and provided the basis for the implementing of tele-health services that would further improve the taking charge of patients, particularly those with longer disease, higher disability, and/or living far from their MSC

Short-term triple therapy with azithromycin for Helicobacter pylori eradication: Low cost, high compliance, but low efficacy

<p>Abstract</p> <p>Background</p> <p>The Brazilian consensus recommends a short-term treatment course with clarithromycin, amoxicillin and proton-pump inhibitor for the eradication of <it>Helicobacter pylori </it>(<it>H. pylori)</it>. This treatment course has good efficacy, but cannot be afforded by a large part of the population. Azithromycin, amoxicillin and omeprazole are subsidized, for several aims, by the Brazilian federal government. Therefore, a short-term treatment course that uses these drugs is a low-cost one, but its efficacy regarding the bacterium eradication is yet to be demonstrated. The study's purpose was to verify the efficacy of <it>H. pylori </it>eradication in infected patients who presented peptic ulcer disease, using the association of azithromycin, amoxicillin and omeprazole.</p> <p>Methods</p> <p>Sixty patients with peptic ulcer diagnosed by upper digestive endoscopy and <it>H. pylori </it>infection documented by rapid urease test, histological analysis and urea breath test were treated for six days with a combination of azithromycin 500 mg and omeprazole 20 mg, in a single daily dose, associated with amoxicillin 500 mg 3 times a day. The eradication control was carried out 12 weeks after the treatment by means of the same diagnostic tests. The eradication rates were calculated with 95% confidence interval.</p> <p>Results</p> <p>The eradication rate was 38% per intention to treat and 41% per protocol. Few adverse effects were observed and treatment compliance was high.</p> <p>Conclusion</p> <p>Despite its low cost and high compliance, the low eradication rate does not allow the recommendation of the triple therapy with azithromycin as an adequate treatment for <it>H. pylori </it>infection.</p

Experimental assessment and numerical modelling of exterior non-conforming beam-column joints with plain bars

The seismic performance of existing Reinforced Concrete (RC) frames is significantly influenced by the behaviour of beam-column intersections, especially in non-conforming buildings with poor structural details and completely unreinforced joints. In literature, a very limited number of studies deals with specimens reinforced with plain hook-ended longitudinal bars, widespread in Italian and Mediterranean building stock, or with the analysis of local aspects, such as the experimental evaluation of joint shear strains. The almost totality of the models proposed in literature for simulating the cyclic behaviour of RC joints was developed and calibrated by means of tests performed on elements with deformed bars, and, thus, these models may be not adequate for elements with hook-ended plain bars, especially due to the peculiarities in terms of failure mode and interaction mechanisms between concrete and steel. This study analyses the experimental cyclic behaviour of four full-scale exterior unreinforced RC beam-column joints with plain reinforcing bars in beams and columns, which differ for joint aspect ratio and beam longitudinal reinforcement ratio. First, experimental global and local responses of such tests – including energy dissipation capacity and observed damage evolution – are analysed. The main deformation mechanisms ascribable to the joint – namely rotation at the interface between beam/columns and joint, and shear deformation of the joint panel – are experimentally evaluated to provide a realistic support for the numerical modelling of this typology of beam-column joints. Then main joint shear strength models existing in codes and literature are compared with the experimental results. Finally, the numerical modelling of the specimens is carried out under monotonic loading to reproduce the envelope of the experimental responses. The joint panel constitutive parameters are defined to reproduce the experimental joint shear stress-strain relationships. Additionally, modelling of bond-slip is particularly taken into account due to the poor quality of steel-concrete interaction in the specific case of plain reinforcing bars