Secuencia operativa de componentes mediante sistemas neurodifusos para análisis de confiabilidad

Las redes neuronales y los sistemas difusos se consideran aproximadores universales, por lo que pueden ser combinadas de tal forma que originen métodos más eficientes en cuanto al mapeo de datos entrada - salida. Este artículo propone la implementación de un sistema neurodifuso que permita construir la secuencia operativa de los componentes de un sistema eléctrico de potencia para estudios de confiabilidad

Ubicación óptima de capacitores, reguladores de tensión y generadores distribuidos en sistemas eléctricos de distribución

Context: With the advent of the smart grid paradigm, electrical distribution network (EDN) operators are making efforts to modernize their power grids through the optimal implementation of distributed generators (DGs) and other devices such as capacitors (CAs) and voltage regulators (VRs). The optimal allocation of such devices is a challenging task involving discrete and integer decision variables. Method: This paper presents an approach for the optimal placement of CAs, VRs and DGs in EDNs. The distinctive feature of the proposed model is the fact that it can be used to optimize the allocation of all of these elements together, in pairs, or separately. The optimal implementation of these elements is formulated as a mixed integer nonlinear programming (MINLP) problem, and it is solved by means of a specialized genetic algorithm (SGA). Results: The proposed methodology was tested on the IEEE 69-bus test system. The results were compared with previous works from the specialized literature, showing the effectiveness and robustness of the model. Conclusions: It was found that the appropriate allocation of CAs, VRs, and DGs results in a significant power loss reduction. It was also found that the proposed model is faster than other techniques proposed in the specialized literature. Acknowledgements: The authors gratefully acknowledge the support from the Colombia Científica program, within the framework of the Ecosistéma Científico (Contract No. FP44842- 218-2018). The authors also acknowledge the support of the State University of Londrina and Universidad Tecnológica de Pereira (UTP).Contexto: Con la llegada del paradigma de las redes inteligentes, los operadores de redes de distribución eléctrica (RDE) están haciendo esfuerzos para modernizar sus redes a través de la implementación óptima de generadores distribuidos (GDs) y otros dispositivos como condensadores (CAs) y reguladores de tensión (VRs). La ubicación óptima de estos dispositivos es una tarea desafiante que involucra variables de decisión discretas y enteras. Método: Este artículo presenta una metodología para la colocación óptima de CAs, VRs y GDs en RDEs. La característica distintiva del modelo propuesto es el hecho de que se puede utilizar para optimizar la ubicación de todos estos elementos a la vez, en pares o por separado. La implementación óptima de estos elementos se formula como un problema de programación no lineal de enteros mixta (PNLEM), y se resuelve mediante un algoritmo genético especializado (AGE). Resultados: La metodología propuesta se probó en el sistema de prueba IEEE de 69 barras. Los resultados se compararon con trabajos previos de la literatura especializada, mostrando la efectividad y robustez del modelo. Conclusiones: Se encontró que la ubicación adecuada de CAs, VRs y GDs resulta en una reducción importante de pérdidas de energía. También se encontró que el modelo propuesto es más rápido que otras técnicas propuestas en la literatura especializada. Agradecimientos: Los autores agradecen el financiamiento del programa Colombia Científica, en el marco de la convocatoria Ecosistema Científico (Contrato No. FP44842- 218-2018). Los autores también agradecen el apoyo de la Universidad de Estadual de Londrina y la Universidad Tecnológica de Pereira (UTP)

Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

METODO DE PUNTOS INTERIORES PARA PROGRAMACIÓN LINEAL APLICADO A PROBLEMAS CON ÓPTIMOS ALTERNATIVOS

En problemas de programación lineal que presentan óptimos alternativos es posible determinar la solución más atractiva de acuerdo a determinadas condiciones del problema. En este documento se presenta una modificación al método de Puntos Interiores Primal-Dual para ser aplicado a problemas deoptimización con múltiples soluciones

METODO DE PUNTOS INTERIORES PARA PROGRAMACIÓN LINEAL APLICADO A PROBLEMAS CON ÓPTIMOS ALTERNATIVOS

En problemas de programación lineal que presentan óptimos alternativos es posible determinar la solución más atractiva de acuerdo a determinadas condiciones del problema. En este documento se presenta una modificación al método de Puntos Interiores Primal-Dual para ser aplicado a problemas deoptimización con múltiples soluciones

WFD Pre and Post

Behavioral data on Willingness to Fight and Die scores from pre and post manipulation

Data from: Neuroimaging “will to fight” for sacred values: an empirical case study with supporters of an Al Qaeda affiliate

Violent intergroup conflicts are often motivated by commitments to abstract ideals such as god or nation, so-called “sacred” values that are relatively insensitive to material incentives or disincentives. There is scant knowledge of how the brain processes costly sacrifices for such cherished causes. We studied willingness to fight and die for sacred values using fMRI among supporters of a radical Islamist group from different neighborhoods in and around Barcelona, Spain. We measured brain activity in radicalized individuals as they indicated their willingness to fight and die for sacred and non-sacred values, and as they reacted to peers’ ratings for the same values. We observed diminished activity in dorsolateral prefrontal cortex (dlPFC), inferior frontal gyrus, and parietal cortex while participants conveyed willingness to fight and die for sacred relative to non-sacred values - regions that have previously been implicated in calculating costs and consequences. These differences could not be attributed to differences between sacred and non-sacred values in emotional intensity, familiarity or salience. An overlapping region of dlPFC was active when viewing conflicting ratings of sacred values from peers, to the extent participants were sensitive to peer influence, suggesting that it is possible to induce flexibility in the way people defend sacred values. Our results are consistent with a view that “devoted actors” motivated by an extreme commitment towards sacred in-group values rely on distinctive neurocognitve processes that can be identified