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With the advancement of technology and the application of new sensors in the electric distribution grid, in order to increase its automation, meeting the idea of smart grids, a concept that has been expanding through the years. This article describes some of the solutions and results that ENEL Distribution São Paulo has achieved, through its R&D (Research and Development) Urban Futurability project, to make its electricity distribution grid automated and in line with trends and future technologies. The project includes the installation of sensors for monitoring and protecting both the overhead and underground electricity distribution grid and medium and low voltage, digitalization of the primary substation and improvements in the communication infrastructure, seeking their complete automation. The project was applied in one of the largest urban centers in the world, the city of São Paulo, Brazil, with a diversity of load profiles, both residential and commercial, being a great place to test new technologies in different scenarios. With the increased application of automation in the electricity distribution grid, ENEL Distribution São Paulo seeks to provide its customers with a better service, with a safer and more reliable electricity distribution grid, monitored practically in real time and with state-of-the-art technologies. Therefore, the end consumers benefit from an electric distribution grid with greater availability and decreased number of interruptions.

This work proposes a mixed-integer linear programming model for the operational cost function of lithium-ion batteries that should be applied in a microgrid centralized controller. Such a controller aims to supply loads while optimizing the leveled cost of energy, and for that, the cost function of the battery must compete with the cost functions of other energy resources, such as distribution network, dispatchable generators, and renewable sources. In this paper, in order to consider the battery lifetime degradation, the proposed operational cost model is based on the variation in its state of health (SOH). This variation is determined by experimental data that relate the number of charge and discharge cycles to some of the most important factors that degrade the lifespan of lithium-ion batteries, resulting in a simple empirical model that depends on the battery dispatch power and the current state of charge (SOC). As proof-of-concept, hardware-in-the-loop (HIL) simulations of a real microgrid are performed considering a centralized controller with the proposed battery degradation cost function model. The obtained results demonstrate that the proposed cost model properly maintains the charging/discharging rates and the SOC at adequate levels, avoiding accelerating the battery degradation with use. For the different scenarios analyzed, the battery is only dispatched to avoid excess demand charges and to absorb extra power produced by the non-dispatchable resources, while the daily average SOC ranges from 48.86% to 65.87% and the final SOC converges to a value close to 50%, regardless of the initial SOC considered.

Through the transformation that the electrical sector has been passing by, improvements in asset management and the guarantee of sustainable and quality services have become essential aspects for power companies. Thus, the digitalization of energy utilities presents itself as an important and crucial process. A concept that involves a variety of innovative trends is the digital twin. It consists of a 3D virtual replica of existing physical objects and real-time monitoring of certain measures. By developing a digital twin in the electrical power grid, a virtual replica of the network is obtained providing network virtual maps, 3D asset models, dynamic and real-time data of grid assets, and IoT sensing. All these data can feed a platform where AI-based models and advanced field operation technologies and solutions will be applied. With a Network Digital Twin©development, applications involving on-field activities can be improved through augmented reality (AR) and virtual reality (VR) to enhance workforce operations. This paper discusses the best practices for the development of a digital twin for the electrical power sector. These practices were found during the development of a project carried out by Enel Distribuição São Paulo, applying a living lab concept in the densest region of Brazil. The results of this paper present 3D images captured with specialized tools, and how they influence the workforce activities of human interface operation. Furthermore, financial and operational returns are presented through a cost–benefit analysis for each relevant aspect.

This paper presents a new family of high power factor for electronic ballasts applied to fluorescent lamps. From the proposed structures, two topologies are presented without the ballast inductor, because the boost inductor, in addition to performing power factor correction, also has the function of limiting and stabilizing the lamp current, besides making it to start. The main characteristics of these topologies are the reduction in the production costs owing to fewer components, the low harmonic distortion in the input current, the lower current in the switches, and the lower DC bus voltage. To verify the proposed design methodology and to provide the condition of unity power factor and stabilization of the lamp current, the experimental results of one prototype is presented.

This work proposes a mixed-integer linear programming model for the operational cost function of lithium-ion batteries that should be applied in a microgrid centralized controller. Such a controller aims to supply loads while optimizing the leveled cost of energy, and for that, the cost function of the battery must compete with the cost functions of other energy resources, such as distribution network, dispatchable generators, and renewable sources. In this paper, in order to consider the battery lifetime degradation, the proposed operational cost model is based on the variation in its state of health (SOH). This variation is determined by experimental data that relate the number of charge and discharge cycles to some of the most important factors that degrade the lifespan of lithium-ion batteries, resulting in a simple empirical model that depends on the battery dispatch power and the current state of charge (SOC). As proof-of-concept, hardware-in-the-loop (HIL) simulations of a real microgrid are performed considering a centralized controller with the proposed battery degradation cost function model. The obtained results demonstrate that the proposed cost model properly maintains the charging/discharging rates and the SOC at adequate levels, avoiding accelerating the battery degradation with use. For the different scenarios analyzed, the battery is only dispatched to avoid excess demand charges and to absorb extra power produced by the non-dispatchable resources, while the daily average SOC ranges from 48.86% to 65.87% and the final SOC converges to a value close to 50%, regardless of the initial SOC considered. [ABSTRACT FROM AUTHOR]

Through the transformation that the electrical sector has been passing by, improvements in asset management and the guarantee of sustainable and quality services have become essential aspects for power companies. Thus, the digitalization of energy utilities presents itself as an important and crucial process. A concept that involves a variety of innovative trends is the digital twin. It consists of a 3D virtual replica of existing physical objects and real-time monitoring of certain measures. By developing a digital twin in the electrical power grid, a virtual replica of the network is obtained providing network virtual maps, 3D asset models, dynamic and real-time data of grid assets, and IoT sensing. All these data can feed a platform where AI-based models and advanced field operation technologies and solutions will be applied. With a Network Digital Twin©development, applications involving on-field activities can be improved through augmented reality (AR) and virtual reality (VR) to enhance workforce operations. This paper discusses the best practices for the development of a digital twin for the electrical power sector. These practices were found during the development of a project carried out by Enel Distribuição São Paulo, applying a living lab concept in the densest region of Brazil. The results of this paper present 3D images captured with specialized tools, and how they influence the workforce activities of human interface operation. Furthermore, financial and operational returns are presented through a cost–benefit analysis for each relevant aspect. [ABSTRACT FROM AUTHOR]

Surfaced-enhanced Ramon scattering (SERS) spectra of pyrazine are analyzed on the basis of the properties of the electronic states of the metal-adsorbate surface complex. Ab initio CIS calculations have been carried out for the Ag[sub 2]-pyrazine complex, which have enabled us to find two excited singlets, namely CT[sub 0];[sup 1]B[sub 1] and CT[sub 1];[sup 1]A[sub 2], with properties quite similar to those of the pyrazine radical anion in its electronic [sup 2]B[sub 3u] and [sup 2]A[sub u] states, respectively, and with energies falling in the range of the exciting photons usually employed in Raman spectroscopy. SERS spectra of pyrazine are compatible with a resonance Raman enhancement mechanism involving electronic transitions between the ground state S[sub 0];[sup 1]A[sub 1] and both CT levels of the surface complex. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The potential-energy surfaces of ethyl azide relevant to its thermal decomposition have been studied theoretically. The geometries of minima and transition states on the S[sub 0] surfaces, as well as the lowest energy points in the seam of crossing of the triplet and singlet surfaces, have been optimized with the complete active space self-consistent field (CAS-SCF) method, and their energies, re-calculated with second-order multireference perturbation (CAS/MP2) theory and corrected by the zero-point energy (ZPE). The reaction mechanism is described by the following steps: (1) CH[sub 3]CH[sub 2]N[sub 3]→CH[sub 3]CH[sub 2]N+N[sub 2], (2a) CH[sub 3]CH[sub 2]N→H[sub 2]+CH[sub 3]CN; (2b) CH[sub 3]CH[sub 2]N→CH[sub 3]CHNH. The CN-N[sub 2] fission of ethyl azide is the rate limiting step (1), leading to ethylnitrene either along a spin-allowed path (1a) or along an alternative spin-forbidden one (1b). Both 1a and 1b channels show barriers of similar heights for CN-N[sub 2] bond fission, ΔE=42 kcal/mol, ΔE being the energy difference between the minimum of the ground singlet state potential-energy surface of ethyl azide and either the singlet transition state (TS1) or the lowest energy point of the intersystem crossing (ISC1), respectively. The decomposition of ethanimine formed in step (2b) has been studied as well and high energetic transition states have been identified for its decomposition. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Focuses on the determination of thermal decomposition of methyl azide using the complete active space self-consistent field method and Moller-Plesset theory. Predicted occurrence of the reaction in two steps via nitrene intermediate; Calculated energy barrier height for both processes.

De un total de 118 pacientes que ingresaron a la consulta prenatal durante el tercer mes de gestación, tenemos resultados preliminares de 76. A cada una de ellas se les practico reacción de Sabin y Feldman y toxoplasmina al tercer y octavo meses de embarazo. Se recuperaron las placentas de aquellas madres que demostraron ascenso serológico y previa digestión artificial, se inoculó parte de las placentas a ratones de laboratorio. Se encontró que el 53.19% de las mujeres están desprovistas de anticuerpos al iniciar la gestación; y un 27.63% mostro actividad serológica: Se logro aislar toxoplasmas en 5 de 7 pacientes estudiadas. Se pudo también demostrar parásitos en el liquido cefalorraquídeo de un niño asintomático, nacido vivo, de una madre que presentaba Toxoplasmas en la placenta.

In this paper, a coordinated-distributed model predictive control (CDMPC) scheme is proposed for discrete-time, linear, unconstrained dynamic systems. The proposed control scheme incorporates a coordinator that communicates with local CDMPC controllers. With the assistance of the coordinator, the local CDMPC controllers adjust their calculated control actions iteratively to achieve the optimal plant-wide operation. A ‘prediction-driven’ algorithm is used to coordinate the local CDMPC controllers. Convergence of the prediction-driven algorithm is shown along with a stability analysis of the closed-loop system under coordinated–distributed control. A simulation example is used to illustrate the effectiveness of the proposed coordinated–distributed control scheme. [ABSTRACT FROM AUTHOR]

Adrenocortical oncocytic neoplasms (oncocytomas) are extremely rare; only approximately 159 cases have been described so far. The majority are nonfunctional and benign. We describe an unusual case of a functional oncocytoma secreting an excess of glucocorticoids (cortisol) and androgens (androstenedione and DHEAS), a pattern of plurihormonal cosecretion previously not reported in men, presenting with endocrine manifestations of Cushing’s syndrome. The neoplasm was considered to be of uncertain malignant potential (borderline) according to the Lin-Weiss-Bisceglia criteria. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the internalization of magnetic nanoparticles (NPs) into dendritic cells (DCs) in order to assess both the final location of the particles and the viability of the cultured cells. The particles, consisting of a metallic iron core covered with carbon, showed no toxic effects on the DCs and had no effect in their viability. We found that mature DCs are able to incorporate magnetic nanoparticles in a range of size from 10nm to ca. 200nm, after 24h of incubation. We describe a method to separate cells loaded with NPs, and analyze the resulting material by electron microscopy and magnetic measurements. It is found that NPs are internalized in lysosomes, providing a large magnetic signal. Our results suggest that loading DCs with properly functionalized magnetic NPs could be a promising strategy for improved vectorization in cancer diagnosis and treatment. [Copyright &y& Elsevier]

The objective of the study was to evaluate the influence of the male gender in the clinical presentation and outcome of systemic lupus erythematosus in a prospective inception cohort of Latin-American patients. Of the 1214 SLE patients included in the GLADEL cohort, 123 were male. Demographic characteristics as well as clinical manifestations, laboratory profile, activity and damage scores were evaluated at onset and during the course of the disease and compared with female patients. The median age at onset of the male patients was 27 and that at diagnosis 29.2 years. Delay to diagnosis was shorter in males (134 versus 185 days, P = 0.01). At onset, men more frequently showed fever (42.3 versus 27.0%, P = 0.001) and weight loss (23.6 versus 11.8%, P = 0.001). During disease course the incident of symptoms was: fever, 67.8 versus 55.6%, P = 0.012; weight loss, 47.2 versus 24.3%, P = 0.001; arterial hypertension, 37.4 versus 25.8%, P = 0.007; renal disease (persistent proteinuria and/or cellular casts), 58.5 versus 44.6%, P = 0.004); and hemolytic anemia, 19.5 versus 10.9%, P = 0.008. The laboratory results showed that: men more frequently had IgG anticardiolipin antibodies (68.2 versus 49%, P = 0.02) and low C3 (61.3 versus 48.1%, P = 0.03); 5/123 men died (4%) compared with 29/1091 women (2.7%). In conclusion, 10% of GLADEL's cohort patients were male. They showed a distinctive profile with shorter delay to diagnosis, higher incidence of fever, weight loss, arterial hypertension, renal disease, hemolytic anemia, IgG anticardiolipin antibodies and low C3. Although not statistically significant, mortality was higher in men. [ABSTRACT FROM AUTHOR]

A systematic method to fit calculated to observed vibrational frequencies has been developed and implemented in a computer program. The procedure consists of the refinement of a scaled quantum mechanical force field (SQMFF) previously obtained according to Pulay's method. The key step in the process is the generation of an intermediate matrix, CΛC[sup T], which is then refined. The above step produces only small corrections to the scaled force constants, yielding a considerable improvement of the fitted frequencies. This scheme of refinement can be carried out using any kind of coordinates. To show the reliability and performance of the proposed method, the force fields of two very different systems, as benzene and tetranitromethane, have been chosen as example tests. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A new general procedure to interpret surface-enhanced Raman scattering (SERS) spectra has been developed in order to clarify the controversy concerning the relevant enhancement mechanism of this type of spectra. The analysis consists of detecting the presence of the charge transfer (CT) enhancement mechanism by correlating the most enhanced SERS bands with the ab initio calculated geometries (ΔQ) and vibrational frequencies (Δv) of the isolated molecule and its radical anion. This CT mechanism is assumed to be identical to that of resonance Raman between the electronic ground state of the metal-adsorbate complex and charge transfer excited states. We consider that these excited states arise when one electron is transferred from the metal to pyrazine. For this reason, they have been labeled from the point of view of pyrazine on the basis on the symmetry of the doublet states of its radical anion. The SERS spectra of pyrazine recorded on silver surface at several electrode potentials have been analyzed on the basis of the Franck-Condon and Herzberg-Teller contributions related to [sup 2]B[sub 3u]-[sup 1]A[sub g] and [sup 2]A[sub u]-[sup 1]A[sub g] transitions. A great deal of experimental facts related to the relative enhancement of in-plane A[sub g], B[sub 3g], and B[sub 1u] modes as well as out-of-plane B[sub 3u], B[sub 2g], and A[sub u] vibrations has been explained. Likewise, it is possible to account for the observation of Raman inactive fundamentals as well as the influence of the forbidden [sup 2]A[sub u]-[sup 1]A[sub g] transition on the SERS spectra if the symmetry of the metal-adsorbate complex and the nonplanarity of the [sup 2]A[sub u] state are taken into account. All the results point out that the CT mechanism is mainly responsible for the SERS features of this molecule studied here. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]