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Patients with heart failure (HF) and preserved ejection fraction (HFpEF), in contrast to those with reduced ejection fraction, are older, have more comorbidities, and are not candidates for effective therapeutic measures. Therefore, they are at high risk for hospital admission and mortality. This study evaluated the benefit of a comprehensive continuous care program (UMIPIC program) in patients with HFpEF.We prospectively analyzed data on 2401 patients with HFpEF attended to in internal medicine departments who form part of the RICA registry. They were divided into 2 groups: one was followed-up on in the UMIPIC program (UMIPIC group, n: 1011) and another received conventional care (RICA group, n: 1390). A total of 753 patients in each group were selected by propensity score matching and admissions and mortality were assessed during 12 months of follow-up after an episode of hospitalization due to HF.Compared to the RICA group, the UMIPIC group had a lower rate of HF admissions (19.2% versus 36.5%, respectively; hazard ratio [HR] = 0.56; 95% confidence interval [CI]: 0.45-0.68; p 0.001) and mortality (12.6% versus 28%, respectively; HR = 0.40; 95% CI: 0.31-0.51; p 0.001). There were no differences in hospitalizations for non-HF causes.Implementation of the UMIPIC program, which is based on comprehensive continuous care, for patients with HFpEF and a high degree of comorbidity reduces both admissions and mortality in the first year of follow-up.

Published data on vitamin D and the quality of life of asthma patients are scarce and disparate. The ACVID clinical trial, published in 2020, showed the efficacy of calcifediol in improving asthma control in asthma patients with vitamin D deficiency. Data on vitamin D and quality of life measured by the Mini-AQLQ questionnaire were analysed: supplemented patients showed improved quality of life compared with a placebo group, and the initial mini-AQLQ scores were improved for both groups.

Over the past decades researchers have described what happens to the water when a polarizing external field is applied to it and changes the bonding forces existing in it. Water evaporation, an essential process in nature, has been targeted in a great number of studies. In this paper, static magnetic fields ranging from 30-to-200 mT were applied to circulating purified water to study their effect on how the evaporation rate changed under different ambient conditions. A statistical approach was employed to verify the significance of the magnetically induced effect. Our results showed that by applying a static magnetic field to the water, the evaporation rate increased at lower temperatures, yielding an evaporation increase for magnetized water of up to at 6 °C. We found too that the circulation of the water did not contribute significantly to the evaporation rate. We used an empirical triadic model to correlate the applied magnetic field with the ambient parameters of temperature and humidity., This work was supported in part by the Ministerio de Ciencia, Innovación y Universidades (ID: PGC2018-096994-B-C22), the Ministerio de Economía y Competitividad -Infraestructura FEDER- (ID: EQC2018-004395-P), and by Funding for open access charge: Universidad de Huelva/ CBUA.

Photovoltaics (PVs) provide new opportunities for radial distribution systems (RDSs) that feed electric vehicle charging stations (EVCSs). However, the accurate assessment of the combined technical impact is problematic because of the uncertainties of sources/loads. In previous research, we developed a technique to assess the impact of PV generation. This new study presents a general analytical technique (GAT) that evaluates the combined impact for an extended time frame. Specifically, the GAT effectively assesses the fulfilment of technical requirements for weekly RDS operating variables as specified in regulations. As our main objective is to improve the assessment accuracy of the EV and PV interaction in RDSs, the weekly assessment was extended to a one-year time period, during which it is possible to capture the total uncertainty. Also, correlation of input variables is handled. The computational cost of the GAT is lower than that associated with Monte-Carlo simulation, which is used to confirm the GAT accuracy. Although the results focus on an RDS located in Spain, GAT is applicable to any RDS and is scalable to different penetration levels. The numerical results show the impact of different correlated and non-correlated case studies on the voltage profile, apparent power flow in lines, and real loss.

espanolLos Simpson es la serie de ficcion televisiva que ha redibujado el termino de exito. Tras treinta anos en antena, continua cautivando audiencias de todo el mundo, con un humor acido y osado, asi como con unos guiones y tramas argumentales, que ironizan sobre cualquier asunto de calado social. La presente investigacion estudia, la alusion a cuestiones de genero, machismo, feminismo, igualdad y reparto de roles, presentes en episodios emitidos entre 1989 y 1997, correspondientes a las ocho primeras temporadas, mediante las tecnicas cualitativas del analisis de discurso y de personajes. Como resultados, se observa que Marge es una mujer sumisa, prototipo de la ama de casa de los 60, no obstante, aplicando un modelo de educacion diferente del recibido, trata de formar a su hija Lisa en valores y con patrones de conducta, que le permitan ser una mujer autonoma e independiente, preparada para desarrollarse plenamente en un contexto distinto al de la segunda decada del siglo XX. Se concluye, que la relacion existente entre Marge y Lisa, madre e hija respectivamente, y el vinculo que ambas establecen con el resto de personajes, plasma el cambio de paradigma de la mujer del siglo XX a la del siglo XXI. EnglishThe Simpsons is the television fiction series that has redrawn the term of success. After thirty years on the air, he continues to captivate audiences around the world, with an acid and daring humor, as well as with some scripts and plot lines, which ironic about any issue of social significance. The present investigation studies the allusion to questions of gender, machismo, feminism, equality and distribution of roles, present in episodes broadcast between 1989 and 1997, corresponding to the first eight seasons, using the qualitative techniques of discourse and character analysis. As results, it is observed that Marge is a submissive woman, prototype of the housewife of the 60s, however, applying a different model of education from the one received, she tries to train her daughter Lisa in values and with behavior patterns, which allow her to be an autonomous and independent woman, prepared to develop fully in a context different from that of the second decade of the 20th century. It is concluded that the relationship between Marge and Lisa, mother and daughter respectively, and the bond that both establish with the rest of the characters, reflects the paradigm shift of women from the 20th century to that of the 21st century.

Photovoltaic (PV) systems are gradually replacing conventional synchronous generators. However, reduced system inertia and lack of dynamic grid support from PV are the main issues that could have a detrimental impact on the transient response in power systems when critical contingencies arise. In this study, the authors modelled and analysed transient and small-signal stability for a representative transmission system with realistic loading scenarios and high PV penetration levels. First, system eigenvalues were calculated to identify critical modes. Thereafter, the results of the small-signal analysis were further expanded by performing transient simulations after critical contingencies. Such contingencies detrimentally excited the critical modes of the system. To carry out this analysis, they implemented a positive-sequence dynamic model of a utility-scale PV unit (USPVU) in the open programming environment MATLAB/Simulink. This dynamic model is based on a Western Electricity Coordinating Council (WECC) generic model (full converter model), which is suitable for electromechanical transient studies. Also included was the model of the PV array, dc-dc converter, and associated control systems. The most critical factors pertaining to the detrimental or beneficial impact of USPVUs on stability were the unit commitment and dispatch strategy and the protection/control strategy during voltage swell and dip events for equivalent PV penetration and loading scenarios.

The case is presented of a 3 year-old girl with mitochondrial disease (subacute necrotizing encephalomyelopathy of Leigh syndrome), v-stage chronic kidney disease of a diffuse mesangial sclerosis, as well as developmental disorders, and diagnosed with hyperthyroidism Graves-Basedow disease. Six weeks after starting the treatment with neo-carbimazole, the patient reported a serious case of agranulocytosis. This led to stopping the anti-thyroid drugs, and was treated successfully with 131I ablation therapy. The relevance of the article is that Graves' disease is uncommon in the paediatric age range (especially in children younger than 6 years old), and developing complications due to a possible late diagnosis. Agranulocytosis as a potentially serious adverse effect following the use of anti-thyroid drugs, and the few reported cases of ablation therapy with 131I at this age, makes this case unique.

The case is presented of a 3 year-old girl with mitochondrial disease (subacute necrotizing encephalomyelopathy of Leigh syndrome), v-stage chronic kidney disease of a diffuse mesangial sclerosis, as well as developmental disorders, and diagnosed with hyperthyroidism Graves-Basedow disease. Six weeks after starting the treatment with neo-carbimazole, the patient reported a serious case of agranulocytosis. This led to stopping the anti-thyroid drugs, and was treated successfully with 131I ablation therapy. The relevance of the article is that Graves’ disease is uncommon in the paediatric age range (especially in children younger than 6 years old), and developing complications due to a possible late diagnosis. Agranulocytosis as a potentially serious adverse effect following the use of anti-thyroid drugs, and the few reported cases of ablation therapy with 131I at this age, makes this case unique.

Secondary radial distribution networks (SRDNs) have been increasingly affected by the uncertainties of harmonic sources associated with photovoltaic (PV) systems. The quantitative assessment of uncertainty propagation causing harmonic distortion and voltage unbalance can be successively handled by probabilistic or affine formulations of harmonic load flows (HLFs). This study developed a general analytical technique (GAT) for solving iterative multiphase HLFs in SRDNs with PV uncertainties. This technique merges the point-estimate method (PEM) and complex affine arithmetic (AA), combined with Legendre series approximation (LGSA). It also models the input correlation. One advantage of this GAT is that the iterative harmonic penetration (IHP) method, modeled for HLF, accounts for the interaction of background harmonic voltage with the PV harmonic current. The first prerequisite was evidently an uncertainty model for PV harmonic current. This paper presents the results for a real unbalanced three-phase SRDN and compares them with those obtained with the Monte-Carlo simulation (MCS). These confirmed the accuracy of GAT as well as its lower computational cost. The numerical results obtained showed that the GAT outperformed the incomplete GAT (IGAT), which is solely based on PEM and Cornish-Fisher expansion, thanks to the ability of AA to bound the outputs used in the LGSA.

Load and generation variations and the random nature of harmonics in non-linear devices (NLDs) are the source of multiple uncertainties that can be handled in harmonic load flows (HLFs) by probabilistic or interval formulations. The paper presents a new combined analytical technique (CAT) for iterative HLFs in the presence of correlated input uncertainties from photovoltaic (PV) systems in radial distribution systems (RDSs). This technique merges the point-estimate method (PEM), a probabilistic formulation, and complex affine arithmetic (AA), an interval formulation. It then uses the information derived in Legendre series approximation (LGSA) to approximate harmonic voltage distributions. Unlike other methods, this CAT includes iterative harmonic penetration (IHP), which provides a way to deal with the interaction of background harmonic voltage on PV harmonic current. The CAT was examined in a real ENDE 100 RDS system. Thanks to PEM and AA, the CAT significantly reduced the computational burden, an evident improvement over the Monte-Carlo simulation (MCS). Furthermore, the simulation results showed that it accurately reconstructed the harmonic voltage distributions (magnitude and phase angle). The iterative approach also underlines the relevance of background harmonic interaction. The CAT outperformed the incomplete CAT (ICAT), which was based solely on a probabilistic HLF formulation.

In this work, the combination of dispersive micro solid-phase extraction (DµSPE) with laser-induced breakdown spectroscopy (LIBS) was evaluated for simultaneous preconcentration and detection of Zn, Cd, Mn, Ni, Cr and Pb in aqueous samples. Two adsorbent materials were tested in the microextraction step, namely graphene oxide and activated carbon. In both cases, the microextraction process consisted in the dispersion of a small quantity of adsorbent in the sample solution containing the analytes. However, while the use of activated carbon required a previous chelation of the metals, this step was avoided with the use of graphene oxide. After extraction, the analytes retained in the adsorbents were analysed by LIBS. Several experimental factors affecting the extraction of the metals (adsorbent amount, pH and extraction time) were optimized by means of the traditional univariate approach. Under optimum microextraction conditions, the analytical features of the proposed DµSPE-LIBS methods were assessed, leading to limits of detection below 100 µg kg−1 and 50 µg kg−1 with the use of activated carbon and graphene oxide, respectively, as adsorbents in the DµSPE process. Trueness evaluation of the most sensitive procedure was carried out by spike and recovery experiments in a real sample of tap water, leading to recovery values in the range 98–110%. This work was supported by the Spanish Ministry of Economy and Competitiveness, (Spain) (Project no. CTQ2016-79991-R and fellowship number BES-2012-058759 (FPI-MICINN)); the Regional Government of Valencia (Spain) (Project no. PROMETEO/2013/038); and the University of Alicante, (Spain) (Grant no. UAUSTI16-04).

Producción Científica, A real end-to-end SDN based GPON scenario to provide a fast, efficient and accurate QoS management is proposed. It is designed to support a novel network management model that permits residential users to control their bandwidth network resources., Ministerio de Ciencia e Innovación (Projects TEC2014-53071-C3-2-P, TEC2015-71932-REDT, TEC2017-84423-C3-1-P and TEC2015-67834-R)

In this study, a method for solving a probabilistic three-phase power flow in radial distribution networks and taking into account the technical constraints of the system is presented. Regulation of voltage is one of the main problems to be taken into account in networks with distributed generation. The present study introduces a probabilistic model to determine the performance of the distribution system. This study considers the random nature of lower heating value of biomass and loads. This study presents a new hybrid technique combining the shuffled frog leaping algorithm with probabilistic three-phase power flow that is solved by Monte Carlo method. Feasible results are achieved in a few iterations. The results show that the proposed technique can be applied to keep the voltages within the limits specified at each node of a distribution network with biomass power plants. The outcomes are attained using the unbalanced distribution system IEEE-13 node and connecting biomass power plants at some nodes. This study shows that the power losses and voltage unbalance are reduced as a result of the inclusion of distributed generation.

This research describes a way to analyze voltage unbalance sensitivity for different maximum sizes of a single-phase photovoltaic system (SPPVS) with multiple PV penetration levels in a typical secondary radial distribution network (SRDN) in Spain. This analysis effectively assesses current requirements as specified in regulations concerning maximum size to be connected. It thus helps distribution network operators to define optimal limits, depending on their context. A stochastic assessment method is proposed to account for any random combination of SPPVSs in an SRDN. In addition, this method evaluates weekly voltage unbalance during a one-year time period, on the basis of 10-min intervals. More specifically, the voltage unbalance in SRDNs with SPPVSs is assessed for each 10-min interval by means of a probabilistic radial three-phase load flow (RTPLF). The results obtained show the maximum sizes of the SPPVS to be connected as a function of the PV penetration level in the SRDN, where high PV penetrations can produce voltage unbalance problems.

Feeding biomass-fueled gas engines (BFGEs) with olive tree pruning residues offers new opportunities to decrease fossil fuel use in road vehicles and electricity generation. BFGEs, coupled to radial distribution systems (RDSs), provide renewable energy and power that can feed electric vehicle (EV) charging stations. However, the combined impact of BFGEs and EVs on RDSs must be assessed to assure the technical constraint fulfilment. Because of the stochastic nature of source/load, it was decided that a probabilistic approach was the most viable option for this assessment. Consequently, this research developed an analytical technique to evaluate the technical constraint fulfilment in RDSs with this combined interaction. The proposed analytical technique (PAT) involved the calculation of cumulants and the linearization of load-flow equations, along with the application of the cumulant method, and Cornish-Fisher expansion. The uncertainties related to biomass stock and its heating value (HV) were important factors that were assessed for the first time. Application of the PAT in a Spanish RDS with BFGEs and EVs confirmed the feasibility of the proposal and its additional benefits. Specifically, BFGEs were found to clearly contribute to the voltage constraint fulfilment. The computational cost of the PAT was lower than that associated with Monte-Carlo simulations (MCSs)., This work is supported by the Spanish National Plan for Scientific, Technical and Innovation Research (Grant No. ENE2013-46205).

—This article shows a method to optimize the reliability of an electric power system by the introduction of distributed generation. The reliability index of the system is determined as the failure probability of the system. A hybrid method that uses a binary shuffled frog-leaping algorithm and probabilistic load flow is proposed to search a large number of combinations for location and size of biomass power plants and photovoltaic units. The combination with the best performance minimizes the reliability index (probability of failure) of the system.

This article presents a method to optimize the reliability of an electric power system by the introduction of distributed generation using biomass as fuel. The reliability index of the system is determined as the failure probability of the system. Probabilistic load flow is used to calculate the reliability index. This probabilistic load flow is solved by the method combined of cumulants and Gram–Charlier expansion. To determine the reliability index a number of contingencies should be simulated, the more the number of contingencies, the more accurate the index is. This probabilistic method uses the random variables as starting data, so both generators and loads are modelled as random variables. Generators considered for distributed generation are biomass fuelled gas engines, that are very abundant in Spain. This paper applies a new method utilizing Shuffled Frog-Leaping Algorithm and probabilistic load flow to solve this problem. Acceptable solutions are reached in a small number of iterations. Numerical applications are presented and considered regarding the power system IEEE 14-bus and including biomass fuelled gas engines at several nodes. The results obtained show the improvement of the reliability index due to the presence of distributed generation.

This paper presents a new hybrid method that combines jumping frog and particle swarm optimization and probabilistic three-phase load flow to improve unbalanced voltages in distribution systems with photovoltaic generators. This paper applies a new three-phase probabilistic load flow based on the Monte Carlo simulation. The voltage regulation is one of the principal problems to be addressed in photovoltaic distributed generation. The proposed method defines the nodes where photovoltaic grid-connected system is connected and their mean power output minimizing the maximum value of voltage unbalances at the nodes. Numerical applications are presented using the unbalanced distribution system IEEE 13-nodes and including photovoltaic generators at several nodes. The results obtained show the decrease in the unbalance factor due to the presence of distributed generation.

This paper shows that in order to solve a probabilistic three phase load flow in radial distribution networks, it is necessary to apply effective techniques that take into account their technical constraints. Among these constraints, voltage regulation is one of the principal problems to be addressed in distributed generation. To evaluate the performance of this distribution system, this paper has developed a probabilistic model that takes into account the random nature of lower heat value of biomass and load. This paper applies a new method utilizing shuffled frog-leaping algorithm and three phase probabilistic load flow combined with the Monte Carlo method to solve this problem. The proposed method determines the nodes where biomass fueled gas engines are connected and their mean power output in order to minimize the voltage unbalances at the nodes. Acceptable solutions are reached in a small number of iterations. Results prove that the proposed method can be applied for the keeping of voltages within desired limits at all load buses of a distribution system with biomass fueled gas engines. Numerical applications are presented and considered regarding the unbalanced distribution system IEEE 13-nodes. The results obtained show the decrease of the unbalance factor due to the presence of distributed generation.

Summary Genealogical and live body weight monthly records from 790 sheep of the Chiapas breed born between 1991 and 2004 were used to characterize the growth curve and estimate (co)variance components for the parameters (A, k and b) of the Gompertz function. The pedigree structure consisted of 790 sheep, including 45 rams and 379 ewes. Estimation of (co)variance components for each growth parameter was achieved using a univariate animal model with the restricted maximum likelihood (REML) method. Estimated values of heritability were: A (adult weight) 0.21 ± 0.06; b (integration constant) 0.25 ± 0.07; k (maturity rate) 0.16 ± 0.06; age at the inflexion estimated as (ln(b)/k) 0.24 ± 0.07; and absolute growth rate as [k*(0.368*A)* ln(A/0.368*A)] 0.22 ± 0.07. The growth of males was 24% (P < 0.05) faster than that of females; adult weight was 25 ± 0.7 kg for males and 23 ± 0.7 kg for females; absolute growth was 59 ± 2 g and 44 ± 2 g per day for males and females respectively. The Chiapas breed of sheep is a small animal with a slow growth curve, probably due to its adaptation to the environmental conditions where it lives. Growth curve can be modified through selection.

The assessment of the technical impact of photovoltaic-distributed generation (PV-DG) units on radial distribution systems (RDSs) is complex because of the probabilistic nature of their output power and the diversity of potential sites where they can be installed. This type of evaluation thus requires a multivariate probabilistic analysis involving non-Gaussian correlated random variables. In a previous study, we applied an analytical technique to assess this technical impact for a single 10-min period. In the research presented in this paper, this technique was improved so that it could be applied during a full year, assuming 10-min intervals for PV and load profiles. This is the time period required to accurately assess the effects of stochastic PV inputs, and to determine the improvement of power quality (PQ) parameters, based on current regulations. This article describes a case study for a rural RDS located in the region of Andalusia in the south of Spain with spatially correlated PV-DG units. Our objective was to improve the analytical technique and also the accuracy of probabilistic methods. In our opinion, this can enhance the operation and planning of PV-DG in RDSs and provides a better understanding of the effects of spatial PV dependence structures.

This paper shows that in order to solve a probabilistic three phase load flow in radial distribution networks, it is necessary to apply effective techniques that take into account their technical constraints. Among these constraints, voltage regulation is one of the principal problems to be addressed in photovoltaic distributed generation. This paper applies a new method utilizing Shuffled Frog-Leaping Algorithm and three phase probabilistic load flow combined with the Monte Carlo method to solve this problem. The objective function used is the power losses expected value. Acceptable solutions are reached in a small number of iterations. Results prove that the proposed method can be applied for the keeping of voltages within desired limits at all load nodes of a photovoltaic grid-connected system. To evaluate the performance of photovoltaic system this paper has developed a probabilistic model that takes into account the random nature of solar irradiance and load. Numerical applications are presented and considered regarding the unbalanced distribution system IEEE 13-nodes and including photovoltaic generators at several nodes. The results obtained show the decrease of the power losses due to the presence of distributed generation.

This article presents a developed method to improve the representation of a voltage-controlled bus in the current injection load flow method. This improvement is based on a hybrid current and power mismatches formulation, where the load bus equations are represented by current mismatches and voltage-controlled buses bus equations are based on power mismatches. In this method, the advantages of the Newton–Raphson method and current injection mismatches method are collected. The total number of equations is reduced, where only one equation is required for each voltage-controlled bus. This article also describes direct modeling of voltage/power control devices in the developed load flow method. The static synchronous compensator can be represented as a voltage-controlled bus node in terms of power mismatch. The static series synchronous compensator and unified power flow controller are modeled by series impedance and two current injections at the corresponding nodes. In the case of unified power flo...

This paper shows that the technical constraints must be considered in radial distribution networks, where the voltage regulation is one of the primary problems to be dealt in distributed generation systems based on biomass fueled engine. Loads and distributed generation production are modeled as random variables. Results prove that the proposed method can be applied for the keeping of voltages within desired limits at all load buses of a distribution system with biomass fueled gas engines. To evaluate the performance of this distribution system, this paper has developed a probabilistic model that takes into account the random nature of lower heat value of biomass and load. The Cornish–Fisher expansion is used for approximating quantiles of a random variable. This work introduces a hybrid method that utilizes a new optimization method based on swarm intelligence and probabilistic radial load flow. It is demonstrated the reduction in computation time achieved by the more efficient probabilistic load flow in comparison to Monte Carlo simulation. Acceptable solutions are reached in a smaller number of iterations. Therefore, convergence is more rapidly attained and computational cost is significantly lower than that required for Monte Carlo methods.

Background Postpartum haemorrhage (PPH) is an unpredictable obstetric emergency that requires a multidisciplinary approach. Pelvic arterial embolization (PAE) is considered as a second-line treatment, although the published results have not been reviewed systematically since 2007. Objectives To evaluate success and complication rates of PAE to treat PPH in the study hospital between 2009 and 2015, and to perform a systematic review of the literature on the reported efficacy and safety of PAE for the management of PPH. Search strategy A systematic review of articles on PAE in English or Spanish was conducted using Medline and the Cochrane Library. Selection criteria All published articles assessing success and complication rates of PAE in cases of PPH. The search was restricted to articles published in English or Spanish between 2000 and 2015, with at least 25 cases. Data collection and analysis Obstetric variables, maternal haemodynamic state, pre-/postembolization management, technique-related variables, post-PAE evolution and complications were recorded in the case series study. Study characteristics, success rates and PAE-related complication rates were recorded in the systematic review. Main results The case series included 29 patients. The majority of these patients were primiparous, with singleton term pregnancies and spontaneous labour. Caesarean section was performed in 62.1% of patients undergoing PAE for PPH. PAE was successful in 89.6% [95% confidence interval (CI) 78.3–100] of cases. Twenty studies were included in the systematic review, providing data from 1739 patients. PAE was successful in 89.4% (95% CI 87.9–90.9) of cases. The mortality rate was 0.9%, and other major complications were uncommon (1.8%). Conclusions PAE was found to be a minimally invasive, highly successful and safe technique for the management of PPH. It should be considered in PPH refractory to initial treatment.

This paper shows that in order to solve a probabilistic load flow in radial distribution networks, it is necessary to apply effective techniques that take into account their technical constraints. Among these constraints, voltage regulation is one of the principal problems to be addressed in photovoltaic distributed generation. Probabilistic load flows can be solved by analytical techniques as well as the Monte Carlo method. Our research study applied an analytical method that combined the cumulant method with the Cornish–Fisher expansion to solve this problem. The Monte Carlo method is used to compare the results of analytical method proposed. To evaluate the performance of photovoltaic distributed generation, this paper describes a probabilistic model that takes into account the random nature of solar irradiance. Therefore, load and photovoltaic distributed generation are modelled as independent/dependent random variables. The results obtained show that the technique proposed gave a better performance than the Monte Carlo method. This technique provided satisfactory solutions with a smaller number of iterations. Therefore, convergence was rapidly attained and computational cost was lower than that required for the Monte Carlo method. Besides, the results revealed how the Cornish–Fisher expansion had a better performance than the Gram–Charlier expansion, when input random variables were non-Gaussian.

This article shows that technical constraints must be considered in radial distribution networks, where voltage regulation is one of the primary problems in distributed generation photovoltaic systems. Loads and distributed generation production are modeled as random variables. Results prove that the proposed method can be applied for keeping voltages within desired limits at all load buses of a photovoltaic grid-connected system. To evaluate the performance of a photovoltaic system, this article has developed a probabilistic model that takes into account the random nature of solar irradiance and load. This work introduces a new method utilizing discrete particle swarm optimization and probabilistic radial load flow. Computer simulation reduction demonstrates better performance of the new probabilistic load flow in comparison to the Monte Carlo simulation. Acceptable solutions are reached in a smaller number of iterations. Therefore, convergence is rapidly attained, and computational cost is low ...

Resumen La utilizacion de la oxcarbazepina como tratamiento anticomicial se ha relacionado con numerosos casos de hiponatremia (sodio [Na] serico Los mecanismos etiopatogenicos son variados y las causas mas promulgadas son la liberacion inadecuada y/o una mayor sensibilidad de la vasopresina tubular, asi como el incremento de agua y la perdida secundaria de Na. Presentamos un caso de una mujer de 67 anos con una hiponatremia secundaria (Na serico

Introduccion El sincope es una patologia frecuente, en ocasiones de dificil diagnostico, de modo que un importante porcentaje queda sin filiar tras realizar pruebas diagnosticas, a veces innecesarias. Metodo Se realiza un analisis retrospectivo de los pacientes ingresados por sincope en un servicio de Medicina Interna del Hospital Clinico Universitario de Zaragoza durante dos anos. Resultados De un total de 2.878 pacientes ingresados en el servicio durante los anos 1999 y 2000, 79 lo fueron por sincope (2,74 %); 45 (57%) hombres y 34 (43%) mujeres, con una edad media de 68,8 anos. Veintisiete pacientes (34%) habian presentado episodios previos de sincope al ingreso. Tras una estancia media de 9,5 dias se llego al diagnostico etiologico en 53 (67%) casos: en 25 pacientes (31,6%) el sincope fue neurologicamente mediado, en 16 (20,25%) fue cardiologico, en 4 (5,06%) neurologico y 8 (10,1%) secundarios a otras causas. A 54 pacientes (68,8%) se les realizo al menos una prueba cardiologica (41 Holter, 32 ecocardiogramas, 6 pruebas de la mesa basculante, 3 maniobras de masaje del seno carotideo, 3 ergometrias, 3 estudios electrofisiologicos, 2 coronariografias y 3 gammagrafias pulmonares de ventilacion/perfusion). A 51 pacientes (64%) se les realizo al menos una prueba neurologica (31 electroencefalogramas [EEG], 42 tomografias axiales computarizadas [TAC], 2 resonancias magneticas nucleares [RMN], 1 doppler transcraneal y 3 electroneuromiogramas). De los registros Holter realizados solo 4 fueron diagnosticos, al igual que 3 de los ecocardiogramas y solo 2 de las TAC realizadas. Ningun EEG fue util para el diagnostico etiologico del sincope. Conclusiones Existe una sobreutilizacion de algunas pruebas diagnosticas (EEG, Holter y TAC cerebral), a pesar de lo cual en un importante porcentaje de casos de sincope no se llega a un diagnostico etiologico (33%). Se propone el uso de algoritmos diagnosticos basados en una minuciosa historia clinica, exploracion fisica y valoracion de ECG que permitirian emitir una hipotesis diagnostica a partir de la cual poder comenzar el estudio con un uso lo mas racional posible de las exploraciones complementarias.