Clasificación de elementos importantes en sistemas eléctricos de potencia según medidas de centralidad en redes y transformación linegraph

Network theory techniques have recently contributed to the analysis of electrical power systems, enabling faster computational solutions. Taking advantage of the topological information of a network, it becomes possible to characterize its elements both locally (individual network components) and globally (interactions and behavior of the components). Identifying the crucial elements within an electrical system involves classifying each component based on its interaction with the entire network, considering, possibly, various operating conditions. Current network centrality measures predominantly focus on nodes, which represent connection buses in the system, to quantify the significance of individual elements. In this study, we employ the linegraph technique to transform links into nodes. Subsequently, we calculate and categorize the links (representing lines and transformers) of different electrical networks found in the literature using three centrality measures. Moreover, our methodology allows for the aggregation or combination of the indices from each measure, leading to a unified classification based on the importance of links in the considered electrical power systems. Analyzing diverse networks reveals a consistent empirical distribution of centrality indices, resulting in similar classifications of significant elements regardless of network size.El análisis de sistemas eléctricos de potencia se ha apoyado, recientemente, en la aplicación de técnicas de la teoría de redes, con la finalidad de obtener soluciones computacionalmente más rápidas. A partir de la información topológica de una red, es posible definir características desde lo local (elementos de la red) hasta lo global (comportamiento e interacción de los elementos). La identificación de elementos importantes de un sistema eléctrico, consiste en clasificar cada uno de los elementos desde su interacción con toda la red, y, posiblemente, tomando en cuenta diversas condiciones de operación del sistema. Las medidas de centralidad en redes, que permiten asignar importancia cuantitativa a los elementos de un sistema, están definidas en su mayoría para los nodos (representan buses de conexión) de las mismas. En este trabajo, a partir de la transformación de enlaces a nodos, según la técnica linegraph, se calculan y clasifican los enlaces (representan líneas y transformadores) de diversas redes eléctricas de la literatura, de acuerdo con tres medidas de centralidad. Adicionalmente, el procedimiento presentado permite agregar o combinar los índices de cada medida, y obtener una única clasificación según su importancia para los enlaces de los sistemas eléctricos de potencia considerados. La diversidad de redes analizadas permite concluir que la distribución empírica de los índices de centralidad es similar, y origina una clasificación de elementos importantes semejantes, independiente de la dimensión de la red

Modelo multiobjetivo para la selección de estrategias óptimas de mantenimiento en sistemas multicomponentes: una aplicación en líneas de transmisión de energía eléctrica

A multi-objective model is proposed for defining optimal maintenance strategies, in systems composed of several interconnected elements. The optimal maintenance strategies derived correspond to a set of efficient actions, focused on maximizing the reliability of the system, and minimizing the associated costs. Optimization is carried out by using evolutionary algorithms type NSGA-II. For the evaluation of the system reliability, a procedure based on Monte Carlo simulation is used, which allows analyzing systems with different performance functions and for component configurations different from the classical ones (series, parallel, k-out-of-N). The proposal is applied to assess electrical power system components, specifically the insulator chains of the transmission lines. Several scenarios illustrate the proposed model. The strategies selected by the model prioritize the most important elements based on costs and/or maintenance. These strategies make up an approximate Pareto front, in which the decision-maker can choose the most suitable strategy according to their interests.En este artículo se formula un modelo multiobjetivo para seleccionar estrategias de mantenimiento óptimas en sistemas formados por varios elementos interconectados. Las aquí planteadas corresponden al conjunto de acciones eficientes, centradas en maximizar la confiabilidad del sistema y, a su vez, minimizar los costos asociados. La optimización se realiza mediante el uso de algoritmos evolutivos tipo NSGA-II. Para evaluar la confiabilidad del sistema se utiliza un procedimiento basado en simulación de Monte Carlo, que permite analizar sistemas con distintas funciones de desempeño y para configuraciones de componentes diferentes a las clásicas (serie, paralelo, k-out-of-N). La propuesta se analiza para los componentes de un sistema eléctrico de potencia, específicamente las cadenas de aisladores de las líneas de transmisión, y varios escenarios de cálculo. Las estrategias seleccionadas por el modelo priorizan los elementos más importantes, según costo o mantenimiento, y conforman un frente de Pareto aproximado donde el decisor puede seleccionar la más adecuada, de acuerdo con sus intereses

Clasificación de elementos importantes en sistemas eléctricos de potencia según medidas de centralidad en redes y transformación linegraph

El análisis de sistemas eléctricos de potencia se ha apoyado, recientemente, en la aplicación de técnicas de la teoría de redes, con la finalidad de obtener soluciones computacionalmente más rápidas. A partir de la información topológica de una red, es posible definir características desde lo local (elementos de la red) hasta lo global (comportamiento e interacción de los elementos). La identificación de elementos importantes de un sistema eléctrico, consiste en clasificar cada uno de los elementos desde su interacción con toda la red, y, posiblemente, tomando en cuenta diversas condiciones de operación del sistema. Las medidas de centralidad en redes, que permiten asignar importancia cuantitativa a los elementos de un sistema, están definidas en su mayoría para los nodos (representan buses de conexión) de las mismas. En este trabajo, a partir de la transformación de enlaces a nodos, según la técnica linegraph, se calculan y clasifican los enlaces (representan líneas y transformadores) de diversas redes eléctricas de la literatura, de acuerdo con tres medidas de centralidad. Adicionalmente, el procedimiento presentado permite agregar o combinar los índices de cada medida, y obtener una única clasificación según su importancia para los enlaces de los sistemas eléctricos de potencia considerados. La diversidad de redes analizadas permite concluir que la distribución empírica de los índices de centralidad es similar, y origina una clasificación de elementos importantes semejantes, independiente de la dimensión de la red

Pharmacology of (2S,4Z)-N-[(2S)-2-hydroxy-2-phenylethyl]-4-(methoxyimino) -1-[(2 -methyl[1,1 -biphenyl]-4-yl)carbonyl]-2-pyrrolidinecarboxamide, a new potent and selective nonpeptide antagonist of the oxytocin receptor.

ABSTRACT We have discovered a new, potent, selective, and orally active oxytocin receptor antagonist, (2S,4Z)-N-[(2S)-2-hydroxy-2-phenylethyl]-4-(methoxyimino)-1-[(2Ј-methyl[1,1Ј-biphenyl]-4-yl)carbonyl]-2-pyrrolidinecarboxamide (compound 1). We report the biochemical, pharmacological, and pharmacokinetic characterization in vitro and in vivo of this compound. Premature birth is a major problem in obstetrics affecting about 10% of all births and being the largest cause of perinatal morbidity and mortality. The impact on society is significant in terms of costs of neonatal intensive care and for the emotional and social stress to the family. The physiopathology of human preterm labor is complex and multifactorial. Preterm increase of uterine activity is a common complication of pregnancy and accounts for many cases of preterm labor. Pharmacological interventions aimed at maintaining uterine quiescence (tocolysis) have been, and are likely to remain, the cornerstone of pharmaceutical management of preterm labor. However, current tocolytic agents (␤-mimetics, magnesium sulfate, calcium channel blockers, or prostaglandin synthesis inhibitors) suffer from a minimal effectiveness and show important fetal and maternal side effects. Therefore, it is obvious that a safe and effective oral treatment delaying spontaneous preterm birth would have tremendous clinical benefits. The peptide hormone oxytocin (OT) is a potent contractor of the human uterus. OT mediates its effect through activation of the G protein-coupled oxytocin receptor (OT-R) that is expressed in myometrial cells. OT-R is coupled to phospholipase C activation, leading to intracellular synthesis of inositol phosphates and mobilization of calcium. In turn, the rise in intracellular calcium concentration promotes a cascade of events, including phosphorylation of myosin, that then acts on actin and induces uterine muscle cell contraction. Before onset of labor and in the term myometrium, the OT-R density Article, publication date, and citation information can be found a

Mineralocorticoid receptor antagonists for heart failure: a real-life observational study

Mineralocorticoid receptor antagonists (MRAs) have been demonstrated to improve outcomes in reduced ejection fraction heart failure (HFrEF) patients. However, MRAs added to conventional treatment may lead to worsening of renal function and hyperkalaemia. We investigated, in a population-based analysis, the long-term effects of MRA treatment in HFrEF patients.Aims Mineralocorticoid receptor antagonists (MRAs) have been demonstrated to improve outcomes in reduced ejection fraction heart failure (HFrEF) patients. However, MRAs added to conventional treatment may lead to worsening of renal function and hyperkalaemia. We investigated, in a population-based analysis, the long-term effects of MRA treatment in HFrEF patients. Methods and results We analysed data of 6046 patients included in the Metabolic Exercise Cardiac Kidney Index score dataset. Analysis was performed in patients treated (n= 3163) and not treated (n= 2883) with MRA. The study endpoint was a composite of cardiovascular death, urgent heart transplantation, or left ventricular assist device implantation. Ten years\u2019survival was analysed through Kaplan\u2013Meier, compared by log-rank test and propensity score matching. At 10 years\u2019follow-up, the MRA-untreated group had a significantly lower number of events than the MRA-treated group (P<0.001). MRA-treated patients had more severe heart failure (higher New York Heart Association class and lower left ventricular ejection fraction, kidney function, and peak VO2). At a propensity-score-matching analysis performed on 1587 patients, MRA-treated and MRA-untreated patients showed similar study endpoint values. Conclusions In conclusion, MRA treatment does not affect the composite of cardiovascular death, urgent heart transplanta- tion or left ventricular assist device implantation in a real-life setting. A meticulous patient follow-up, as performed in trials, is likely needed to match the positive MRA-related benefits observed in clinical trials

A survey of clinical features of allergic rhinitis in adults

Background: Allergic rhinitis (AR) has high prevalence and substantial socio-economic burden. Material/Methods: The study included 35 Italian Centers recruiting an overall number of 3383 adult patients with rhinitis (48% males, 52% females, mean age 29.1, range 18\u201345 years). For each patient, the attending physician had to fill in a standardized questionnaire, covering, in particular, some issues such as the ARIA classification of allergic rhinitis (AR), the results of skin prick test (SPT), the kind of treatment, the response to treatment, and the satisfaction with treatment. Results: Out of the 3383 patients with rhinitis, 2788 (82.4%) had AR: 311 (11.5%) had a mild intermittent, 229 (8.8%) a mild persistent, 636 (23.5%) a moderate-severe intermittent, and 1518 (56.1%) a moderate-severe persistent form. The most frequently used drugs were oral antihistamines (77.1%) and topical corticosteroids (60.8%). The response to treatment was judged as excellent in 12.2%, good in 41.3%, fair in 31.2%, poor in 14.5%, and very bad in 0.8% of subjects. The rate of treatment dissatisfaction was significantly higher in patients with moderate-to-severe AR than in patients with mild AR (p<0.0001). Indication to allergen immunotherapy (AIT) was significantly more frequent (p<0.01) in patients with severe AR than with mild AR. . Conclusions: These fndings confirm the appropriateness of ARIA guidelines in classifying the AR patients and the association of severe symptoms with unsuccessful drug treatment. The optimal targeting of patients to be treated with AIT needs to be reassessed

DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR&nbsp;=&nbsp;2.05, 95%CI&nbsp;=&nbsp;1.39–3.02, p&nbsp;&lt;&nbsp;0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR&nbsp;=&nbsp;0.42, 95%CI&nbsp;=&nbsp;0.18–0.99, p&nbsp;=&nbsp;0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P &lt; .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

Evacetrapib and Cardiovascular Outcomes in High-Risk Vascular Disease

BACKGROUND: The cholesteryl ester transfer protein inhibitor evacetrapib substantially raises the high-density lipoprotein (HDL) cholesterol level, reduces the low-density lipoprotein (LDL) cholesterol level, and enhances cellular cholesterol efflux capacity. We sought to determine the effect of evacetrapib on major adverse cardiovascular outcomes in patients with high-risk vascular disease. METHODS: In a multicenter, randomized, double-blind, placebo-controlled phase 3 trial, we enrolled 12,092 patients who had at least one of the following conditions: an acute coronary syndrome within the previous 30 to 365 days, cerebrovascular atherosclerotic disease, peripheral vascular arterial disease, or diabetes mellitus with coronary artery disease. Patients were randomly assigned to receive either evacetrapib at a dose of 130 mg or matching placebo, administered daily, in addition to standard medical therapy. The primary efficacy end point was the first occurrence of any component of the composite of death from cardiovascular causes, myocardial infarction, stroke, coronary revascularization, or hospitalization for unstable angina. RESULTS: At 3 months, a 31.1% decrease in the mean LDL cholesterol level was observed with evacetrapib versus a 6.0% increase with placebo, and a 133.2% increase in the mean HDL cholesterol level was seen with evacetrapib versus a 1.6% increase with placebo. After 1363 of the planned 1670 primary end-point events had occurred, the data and safety monitoring board recommended that the trial be terminated early because of a lack of efficacy. After a median of 26 months of evacetrapib or placebo, a primary end-point event occurred in 12.9% of the patients in the evacetrapib group and in 12.8% of those in the placebo group (hazard ratio, 1.01; 95% confidence interval, 0.91 to 1.11; P=0.91). CONCLUSIONS: Although the cholesteryl ester transfer protein inhibitor evacetrapib had favorable effects on established lipid biomarkers, treatment with evacetrapib did not result in a lower rate of cardiovascular events than placebo among patients with high-risk vascular disease. (Funded by Eli Lilly; ACCELERATE ClinicalTrials.gov number, NCT01687998 .)