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This article tackles secondary voltage recovery problem in islanded microgrids with the aim of reducing communication frequency among distributed generation (DG) units, while maintaining desired performance and saving communication network workload. To pursue this objective, a distributed proportional-integral-derivative controller is first introduced, whose sampled-data implementation is enabled by leveraging the finite-difference approximation for the derivative action, which leads to a distributed proportional-integral-retarded (PIR) controller with a small enough sampling period . Then, the resulting fully distributed PIR control law is combined with a dynamic event-triggered mechanism (DETM), which embeds Zeno-freeness property and avoids the requirement of continuous transmission in triggering process. Thus, the communication burden is significantly mitigated and the waste of communication resources is avoided. By exploiting Lyapunov-Krasovkii method, we derive exponential stability conditions expressed as linear matrix inequalities (LMIs), whose solution allows evaluating the maximum sampling period and DETM parameters preserving the stability of the microgrid. A thorough numerical analysis, carried out on the standard IEEE 14-bus test system, confirms the theoretical derivation.
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The accurate analysis of Electrocardiogram waveform plays a crucial role for supporting cardiologist in detecting and diagnosing the heartbeat disorders. To improve their detection accuracy, this work is devoted to the design of a novel classification algorithm which is composed of a cascade of two convolutional neural network (CNN), i.e a Binary CNN allowing the detection of the arrhythmic heartbeat and a Multiclass CNN able to recognize the specific disorder. Moreover, by combining the cascade architecture solution with a rule-based data splitting, which leverages the subject-exclusive and balances among the classes criteria, it is possible predicting the health status of unseen patients. Numerical results, carried out considering Massachusetts Institute of Technology-Beth Israel Hospital arrhythmia database, disclose a classification accuracy of 96.2 % . Finally, a cross-database performance evaluation and a comparison analysis w.r.t. the current state-of-art further disclose the effectiveness and the efficiency of the proposed solution, as well as its benefits in terms of patient health status prediction.
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BACKGROUND: Neonatal infections represent one of the six main types of healthcare-associated infections and have resulted in increasing mortality rates in recent years due to preterm births or problems arising from childbirth. Although advances in obstetrics and technologies have minimized the number of deaths related to birth, different challenges have emerged in identifying the main factors affecting mortality and morbidity. Dataset characterization: We investigated healthcare-associated infections in a cohort of 1203 patients at the level III Neonatal Intensive Care Unit (ICU) of the "Federico II" University Hospital in Naples from 2016 to 2020 (60 months). METHODS: The present paper used statistical analyses and logistic regression to identify an association between healthcare-associated blood stream infection (HABSIs) and the available risk factors in neonates and prevent their spread. We designed a supervised approach to predict whether a patient suffered from HABSI using seven different artificial intelligence models. RESULTS: We analyzed a cohort of 1203 patients and found that birthweight and central line catheterization days were the most important predictors of suffering from HABSI. CONCLUSIONS: Our statistical analyses showed that birthweight and central line catheterization days were significant predictors of suffering from HABSI. Patients suffering from HABSI had lower gestational age and birthweight, which led to longer hospitalization and umbilical and central line catheterization days than non-HABSI neonates. The predictive analysis achieved the highest Area Under Curve (AUC), accuracy and F1-macro score in the prediction of HABSIs using Logistic Regression (LR) and Multi-layer Perceptron (MLP) models, which better resolved the imbalanced dataset (65 infected and 1038 healthy).
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Infección Hospitalaria , Unidades de Cuidado Intensivo Neonatal , Inteligencia Artificial , Peso al Nacer , Atención a la Salud , Femenino , Humanos , Recién Nacido , EmbarazoRESUMEN
The development of autonomous connected vehicles, moving as a platoon formation, is a hot topic in the intelligent transportation system (ITS) research field. It is on the road and deployment requires the design of distributed control strategies, leveraging secure vehicular ad-hoc networks (VANETs). Indeed, wireless communication networks can be affected by various security vulnerabilities and cyberattacks leading to dangerous implications for cooperative driving safety. Control design can play an important role in providing both resilience and robustness to vehicular networks. To this aim, in this article, we tackle and solve the problem of cyber-secure tracking for a platoon that moves as a cohesive formation along a single lane undergoing different kinds of cyber threats, that is, application layer and network layer attacks, as well as network induced phenomena. The proposed cooperative approach leverages an adaptive synchronization-based control algorithm that embeds a distributed mitigation mechanism of malicious information. The closed-loop stability is analytically demonstrated by using the Lyapunov-Krasovskii theory, while its effectiveness in coping with the most relevant type of cyber threats is disclosed by using PLEXE, a high fidelity simulator which provides a realistic simulation of cooperative driving systems.
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Intradermal therapy, known as mesotherapy, is a technique used to inject a drug into the surface layer of the skin. In particular, it involves the use of a short needle to deposit the drug in the dermis. The intradermal microdeposit modulates the drug's kinetics, slowing absorption and prolonging the local mechanism of action. It is successfully applied in the treatment of some forms of localized pain syndromes and other local clinical conditions. It could be suggested when a systemic drug-sparing effect is useful, when other therapies have failed (or cannot be used), and when it can synergize with other pharmacological or nonpharmacological therapies. Despite the lack of randomized clinical trials in some fields of application, a general consensus is also reached in nonpharmacological mechanism of action, the technique execution modalities, the scientific rationale to apply it in some indications, and the usefulness of the informed consent. The Italian Mesotherapy Society proposes this position paper to apply intradermal therapy based on scientific evidence and no longer on personal bias.
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Analgésicos/administración & dosificación , Dermis/metabolismo , Mesoterapia/métodos , Dolor/prevención & control , Absorción Cutánea , Analgésicos/farmacocinética , Animales , Predicción , Humanos , Inyecciones Intradérmicas , Italia , Mesoterapia/instrumentación , Mesoterapia/tendencias , Guías de Práctica Clínica como Asunto , Resultado del TratamientoRESUMEN
Coronary artery disease is one of the most prevalent chronic pathologies in the modern world, leading to the deaths of thousands of people, both in the United States and in Europe. This article reports the use of data mining techniques to analyse a population of 10,265 people who were evaluated by the Department of Advanced Biomedical Sciences for myocardial ischaemia. Overall, 22 features are extracted, and linear discriminant analysis is implemented twice through both the Knime analytics platform and R statistical programming language to classify patients as either normal or pathological. The former of these analyses includes only classification, while the latter method includes principal component analysis before classification to create new features. The classification accuracies obtained for these methods were 84.5 and 86.0 per cent, respectively, with a specificity over 97 per cent and a sensitivity between 62 and 66 per cent. This article presents a practical implementation of traditional data mining techniques that can be used to help clinicians in decision-making; moreover, principal component analysis is used as an algorithm for feature reduction.
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Enfermedad de la Arteria Coronaria , Algoritmos , Enfermedad de la Arteria Coronaria/diagnóstico , Análisis Discriminante , Europa (Continente) , Humanos , Análisis de Componente PrincipalRESUMEN
OBJECTIVES: In the context of the gradual development of artificial intelligence in health care, the clinical decision support systems (CDSS) play an increasing crucial role in improving the quality of the therapeutic and diagnostic efficiency in health care. The fuzzy logic (FL) provides an effective means for dealing with uncertainties in the health decision-making process; therefore, FL-based CDSS becomes a very powerful tool for data and knowledge management, being able to think like an expert clinician. This work proposes an FL-based CDSS for the evaluation of renal function in posttransplant patients. METHOD: Based on the data provided by the Department of Nephrology of the University Hospital Federico II of Naples, a statistical sample is selected according to appropriate inclusion criteria. Four fuzzy inference systems are implemented monitoring the renal function by the level of proteinuria and the glomerular filtration rate (GFR). RESULTS: The systems show an accuracy of more than 90% and the outputs are provided through easy to read graphics, so that physicians can intuitively monitor the patient's clinical status, with the objective to improve drugs dosage and reduce medication errors. CONCLUSIONS: We propose that the CDSSs for the assessment and follow-up of kidney-transplanted patients built in this study are applicable to clinical practice.
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Sistemas de Apoyo a Decisiones Clínicas , Lógica Difusa , Inteligencia Artificial , Humanos , Riñón/fisiología , Monitoreo FisiológicoRESUMEN
The superficial injection needling botulinum (SINB) technique is the dermal injection of microdoses of botulin toxin, not by traditional syringe but with needling technique that consists in multiple microdroplets by electrical device. The intention is to decrease sweat and sebaceous gland activity to improve skin texture and sheen and to target the superficial layer of muscles that find attachment to the undersurface of the dermis causing visible rhytides. The technique is for treatment of face and neck by the injection of the botulin toxin into the dermis or in subdermal plane to improve skin texture, smoothen horizontal creases, and decrease vertical banding of the neck as well as to achieve better apposition of the platysma to the jawline and neck, improving contouring of the cervicomental angle. The botox solution is hyperconcentrated when compared to traditional dilution or compared to microbotox or mesobotox. Furthermore, the injection technique is different because spreading superficial microdroplets are not performed, but small, homogeneous, and controlled amounts of solution are injected. Each 0.8-mL syringe contains 50 units of onabotulinumtoxinA. The solution is delivered intradermally, using an electrical needling pen and setting the depth penetration of the needles at 3 to 3.5 mm. The 2 conjugated techniques play a 2-fold action on the skin. The technique was applied to a group of 63 patients dealing with face, forehead, cheekbones, and neck.
La technique d'injection superficielle de botuline à l'aiguille (SINB d'après l'acronyme anglais) consiste à procéder à l'injection dermique de microdoses de toxine botulique, non pas à l'aide de la seringue habituelle, mais d'une technique à l'aiguille constituée de multiples microgouttes injectées par un dispositif électrique. On vise ainsi à réduire l'activité sudoripare et sébacée pour améliorer la texture et la brillance de la peau et cibler la couche superficielle des muscles attachés à la face inférieure du derme, responsables de rhytides visibles. La technique vise le traitement de la face et du cou par l'injection de toxine botulique dans le derme ou le plan sous-cutané pour améliorer la texture de la peau, lisser les plis horizontaux, réduire les bandes verticales du cou, obtenir une meilleure apposition du muscle peaucier sur les maxillaires et le cou et ainsi améliorer le contour de l'angle cervicomentonnier. La solution de botox est hyperconcentrée par rapport à la dilution habituelle ou à la dilution au microbotox ou au mésobotox. De plus, la technique d'injection est différente puisqu'on n'étend pas de microgouttes superficielles, mais qu'on injecte de petites quantités de solutions homogènes et contrôlées. Chaque seringue de 0,8 mL contient 50 unités d'onabotulinum toxine A. La solution est administrée par voie intradermique au moyen d'un stylo injecteur électrique dont la profondeur d'insertion se situe entre 3,0 et 3,5 mm. Les deux techniques conjuguées ont une double action sur la peau. La technique a été utilisée dans un groupe de 63 patients, sur le visage, le front, les pommettes et le cou.
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Systems biology aims at building computational models of biological pathways in order to study in silico their behaviour and to verify biological hypotheses. Modelling can become a new powerful method in molecular biology, if correctly used. Here we present step-by-step the derivation and identification of the dynamical model of a biological pathway using a novel synthetic network recently constructed in the yeast Saccharomyces cerevisiae for In-vivo Reverse-Engineering and Modelling Assessment. This network consists of five genes regulating each other transcription. Moreover, it includes one protein-protein interaction, and its genes can be switched on by addition of galactose to the medium. In order to describe the network dynamics, we adopted a deterministic modelling approach based on non-linear differential equations. We show how, through iteration between experiments and modelling, it is possible to derive a semi-quantitative prediction of network behaviour and to better understand the biology of the pathway of interest.
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Simulación por Computador , Redes Reguladoras de Genes/fisiología , Modelos Genéticos , Saccharomyces cerevisiae/fisiología , Algoritmos , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II/genética , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Dinámicas no Lineales , Organismos Modificados Genéticamente/fisiología , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Reproducibilidad de los Resultados , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Biología Sintética , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Systems and Synthetic Biology use computational models of biological pathways in order to study in silico the behaviour of biological pathways. Mathematical models allow to verify biological hypotheses and to predict new possible dynamical behaviours. Here we use the tools of non-linear analysis to understand how to change the dynamics of the genes composing a novel synthetic network recently constructed in the yeast Saccharomyces cerevisiae for In-vivo Reverse-engineering and Modelling Assessment (IRMA). Guided by previous theoretical results that make the dynamics of a biological network depend on its topological properties, through the use of simulation and continuation techniques, we found that the network can be easily turned into a robust and tunable synthetic oscillator or a bistable switch. Our results provide guidelines to properly re-engineering in vivo the network in order to tune its dynamics.
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Relojes Biológicos/genética , Genes de Cambio/genética , Saccharomyces cerevisiae/genética , Simulación por Computador , Retroalimentación Fisiológica , Regulación Fúngica de la Expresión Génica , Genes Fúngicos/genética , Factores de TiempoRESUMEN
Systems biology approaches are extensively used to model and reverse engineer gene regulatory networks from experimental data. Conversely, synthetic biology allows "de novo" construction of a regulatory network to seed new functions in the cell. At present, the usefulness and predictive ability of modeling and reverse engineering cannot be assessed and compared rigorously. We built in the yeast Saccharomyces cerevisiae a synthetic network, IRMA, for in vivo "benchmarking" of reverse-engineering and modeling approaches. The network is composed of five genes regulating each other through a variety of regulatory interactions; it is negligibly affected by endogenous genes, and it is responsive to small molecules. We measured time series and steady-state expression data after multiple perturbations. These data were used to assess state-of-the-art modeling and reverse-engineering techniques. A semiquantitative model was able to capture and predict the behavior of the network. Reverse engineering based on differential equations and Bayesian networks correctly inferred regulatory interactions from the experimental data.