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A new contact model is proposed to improve the simulation of the hydration of granular bentonite mixtures. When these mixtures are abstracted as a discrete set of continuous systems in contact, excessively low predictions of swelling pressures are obtained when simulating the early stages of hydration using a plane axisymmetric approximation. This is especially true for relatively open structured mixtures with an average dry density less than 1.5 Mg/m3. The proposed contact model has allowed improved predictions while maintaining the axisymmetric analysis in the demanding inspection tests analysed. Hence, it is an interesting tool to simulate the whole homogenisation process of open granular bentonite mixtures. However, it is necessary to intensify its validation by analysing new experimental evidence, and to evaluate its development, because given its simplicity it presents some difficulties to reproduce the collapse of the megapores when hydration progresses.

Background/Objectives: Neck circumference (NC) has been proposed as a simple measurement to identify patients with overweight and obesity. It has been found that adipose tissue at the cervical level is associated with the presence of metabolic alterations. The aim of this study was to estimate the association between NC and indicators of Metabolic Syndrome (MS) to subsequently estimate its capacity to identify the risk of MS compared to waist circumference (WC) and Body Mass Index (BMI). Methods: A cross-sectional study was carried out with a sample of 286 children 6–9 years old who attended six public primary schools in Jalisco, Mexico. Pearson’s correlation coefficients along with sensitivity and specificity tests were performed to analyze the relationship between NC and MS indicators. Odds ratio (OR) and concordance analyses were performed considering the Kappa index. Results: NC showed statistically significant correlations with all MS indicators except for LDL cholesterol and total cholesterol. The cut-off points of NC to identify MS according to sex was >27.4 cm for girls and >29.8 cm for boys. The association of NC with values above the cutoff point and the presence of MS was OR: 21.6 (CI: 7.11–65.74). Conclusions: NC represents a simple and cost-effective alternative to identify children at risk of MS when compared to BMI and WC.

Background: Neck circumference (NC) has been proposed as an indicator of upper trunk adiposity and a potential indicator of metabolic risk. The objective was to evaluate NC and its correlation with body fat percentage (BF%) and other indicators of adiposity in children with normal weight, overweight, and obesity. Methods: In a cross-sectional study, 112 children 5 to 10 years of age were included in the outpatient clinic from a public hospital. Measures of weight and height to calculate BMI (kg/m2), NC, mid-upper arm circumference, waist circumference, and tricipital skinfold thickness. Body composition measurements were performed using an electrical bioimpedance device (BIA). The relationship between anthropometric variables and BF% obtained by BIA was determined using Spearman correlation tests. Multivariate models were constructed with BF% as the dependent variable and anthropometric parameters as independent. Results: In the entire group, there was a direct correlation between NC and BF% (r = 0.50, p < 0.001), but lost statistical significance in the case of normal weight. The relationship maintained its significance in subjects from the overweight and obesity groups. In multivariate models, BMI exhibited the highest correlation with BF%, followed by waist circumference and mid-upper arm circumference; for NC, the R2 value was 0.30 (p < 0.001). Conclusions: Neck circumference is useful in the screening of population groups with the advantage of not requiring any specialized instruments for its measurement other than a tape measure. BMI and waist circumference were the best indicators of general and central adiposity, respectively.

This research focuses on the potential for microbial treatment to stabilize compacted soils, which are often utilized in earthwork projects. A silt–clay sand was used to describe a particular kind of soil. The suggested remedy makes use of the soil’s naturally occurring urea and Ca2+, as well as microorganisms introduced to the compaction water. Two alternative initial water-content types were examined: those on the dry side and those close to the ideal Proctor conditions. Bacillaceae microorganisms were used to induce microbial CaCO3 precipitation and improve the hydraulic and mechanical properties of the compacted soil. The samples were biotreated and immediately compacted, so that the precipitation of calcium carbonate during the curing process took place in the contact areas between the particles (biocementation) and in the pore space (bioclogging). A set of techniques were used to study the ageing effects, such as the water-retention curve by dew-points psychrometer, mercury porosimetry intrusion, permeability, ultrasonic pulse velocity, resonant column, and unconfined and tensile-compression tests. During the ageing, it was observed that the bacterial activity consumed water for the hydrolysis of urea and other intermediate reactions to precipitate CaCO3. This process resulted in a retraction of the microstructure and a change in the macrostructure. The bioclogging phenomenon was more evident in the soil microstructure, while the biocementation process was easier to observe in the macrostructure. The suction’s effects on the soil stiffness were studied in detail, and a significant increase was detected. Despite these water-content losses, which caused soil stiffening by increasing the suction, it was still feasible to identify the gradual rise in small-strain stiffness throughout incubation. The unconfined and tensile-compression tests showed a similar progressive increase in terms of peak compressive and peak splitting strength during the incubation. These results are of interest when microbiological treatments are applied in soils to produce cementitious materials, with the present investigation demonstrating a complete study of their geotechnical behaviour.

A new multilevel topology for an open-end winding motor drive is proposed in this article, presenting a similar structure to the cascaded H-bridge multilevel inverter. The proposed topology combines three-phase and single-phase conventional H-bridge voltage source inverters. The topology is flexible, allowing to increase the number of voltage levels through the simple integration of new single-phase H-bridge inverters connected in wye. Based on this topology, it is possible to obtain two different configurations. These modular multilevel topologies can be easily extended, both in terms of voltage level and the number of voltage levels. The topology is characterized by the capability to a supply higher voltage to the motor windings or use lower dc voltages when compared with classical solutions. Well-known modulation schemes, such as the multilevel sinusoidal pulsewidth modulation technique, can be easily adapted to the proposed topology. The operation and characteristics of the two configurations for the proposed multilevel topology are confirmed by several experimental tests realized through a laboratory prototype.

Hardware-in-the-loop (HIL) testing methods by means of HIL units or real-time simulators (RTS), are becoming broadly accepted for validating of control systems in many technical areas. This new approach brings advantages such as the acceleration of the industrial and the research development cycle and offers a risk-free and flexible environment for the testing and the evaluation stages before the control deployment in the physical system. Nevertheless, the realization of such methodology can be very challenging in some large or complex plants. In this scenario, a proper simulation of the physical system, that is, the development of its accurate digital twin, demands a suitable and reliable sectioning of the different components into different parts running in parallel into different HIL units. This is the case of a nanogrid (nG) involving some prosumers with renewable energy resources (RES), and their corresponding multiple power electronic converters. These power electronic converters operate at high switching frequencies, which require a very low simulation time step, as well as a high number of input and output signals in closed-loop operation. This work analyzes in detail how to realize a digital twin of a two-prosumer residential nG including a photovoltaic (PV)-battery assisted three-level T-type (3L T-Type) inverter and managed by a hierarchical grid-forming (GFM) control structure by means of RTS based on the RT Box 1 by Plexim. The analysis allows to test the proposed GFM controls and the control hardware in steady and transient conditions, validating their accurate performance.

Purpose: To evaluate the diagnostic accuracy of machine learning (ML) techniques applied to radiomic features extracted from OCT and OCT angiography (OCTA) images for diabetes mellitus (DM), diabetic retinopathy (DR), and referable DR (R-DR) diagnosis. Design: Cross-sectional analysis of a retinal image dataset from a previous prospective OCTA study (ClinicalTrials.gov NCT03422965). Participants: Patients with type 1 DM and controls included in the progenitor study. Methods: Radiomic features were extracted from fundus retinographies, OCT, and OCTA images in each study eye. Logistic regression, linear discriminant analysis, support vector classifier (SVC)-linear, SVC-radial basis function, and random forest models were created to evaluate their diagnostic accuracy for DM, DR, and R-DR diagnosis in all image types. Main Outcome Measures: Area under the receiver operating characteristic curve (AUC) mean and standard deviation for each ML model and each individual and combined image types. Results: A dataset of 726 eyes (439 individuals) were included. For DM diagnosis, the greatest AUC was observed for OCT (0.82, 0.03). For DR detection, the greatest AUC was observed for OCTA (0.77, 0.03), especially in the 3 × 3 mm superficial capillary plexus OCTA scan (0.76, 0.04). For R-DR diagnosis, the greatest AUC was observed for OCTA (0.87, 0.12) and the deep capillary plexus OCTA scan (0.86, 0.08). The addition of clinical variables (age, sex, etc.) improved most models AUC for DM, DR and R-DR diagnosis. The performance of the models was similar in unilateral and bilateral eyes image datasets. Conclusions: Radiomics extracted from OCT and OCTA images allow identification of patients with DM, DR, and R-DR using standard ML classifiers. OCT was the best test for DM diagnosis, OCTA for DR and R-DR diagnosis and the addition of clinical variables improved most models. This pioneer study demonstrates that radiomics-based ML techniques applied to OCT and OCTA images may be an option for DR screening in patients with type 1 DM. Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.

Abstract Background There is a possibility that excess body fat affects bone mass gain and may compromise skeletal health in obese children. The purpose of the study was to identify the relationship between bone mineral density (BMD) and body composition in normal weight, overweight and obese children. Methods This was a cross-sectional study of 6- to 11-year-old children who attended the hospital's outpatient clinic. They were apparently healthy and had no history of prematurity, low birth weight, or chronic diseases. Body mass index (BMI) was used to identify subjects as normal weight, overweight or obese. BMD and body composition were assessed by dual energy X–ray absorptiometry. The BMD values (total and lumbar spine) were compared between normal weight, overweight and obese children. Correlation coefficients were calculated, and multivariate models were performed. Results Forty-nine children were included: 16 with normal weight, 15 that were overweight and 18 with obesity; the mean age was 8.4 ± 1.7 years. All the participants had a normal BMD (> – 2 SD). BMD was higher in obese children and had a positive correlation with total and trunk lean mass in the three study groups (p

When classifiers face imbalanced class distributions, they often misclassify minority class samples, consequently diminishing the predictive performance of machine learning models. Existing oversampling techniques predominantly rely on the selection of neighboring data via interpolation, with less emphasis on uncovering the intrinsic patterns and relationships within the data. In this research, we present the usefulness of an algorithm named RuLer to deal with the problem of classification with imbalanced data. RuLer is a learning algorithm initially designed to recognize new sound patterns within the context of the performative artistic practice known as live coding. This paper demonstrates that this algorithm, once adapted (Ad-RuLer), has great potential to address the problem of oversampling imbalanced data. An extensive comparison with other mainstream oversampling algorithms (SMOTE, ADASYN, Tomek-links, Borderline-SMOTE, and KmeansSMOTE), using different classifiers (logistic regression, random forest, and XGBoost) is performed on several real-world datasets with different degrees of data imbalance. The experiment results indicate that Ad-RuLer serves as an effective oversampling technique with extensive applicability.

La creciente epidemia de obesidad ha sido uno de los retos más importantes de salud pública en México durante los últimos años. Con apoyo de la Federación Mundial de Obesidad, en 2021 formamos un grupo de profesionales para identificar y resumir las acciones prioritarias en las que puede enfocarse nuestro país para hacer frente a esta epidemia. Al proceso de desarrollo y discusión de este grupo se sumaron más de 1 000 profesionales de la salud para retomar recomendaciones de documentos y guías de alto nivel previamente publicados. En conmemoración del Día Mundial de la Obesidad, en este 2022 se presenta esta postura como insumo para el desarrollo de acciones en el ámbito profesional y de los diferentes sectores, en la que se incluyen 10 recomendaciones de acción, desde la perspectiva poblacional hasta la atención individualizada, y se enfatiza en la importancia de la participación social, de las intervenciones integrales con visión centrada en la persona y de la sostenibilidad planetaria, además de mejorar la educación y las campañas de difusión, propiciar un ambiente promotor de entornos activos y blindar de conflictos de interés los esfuerzos de prevención y control. La postura hace un llamado para abordar la obesidad de manera seria, con base en la evidencia científica, oportuna e integral, con enfoque de curso de vida, de forma ética y sensible, y sin perpetuar las barreras del estigma de peso en la sociedad.

Objetivo: Revisar la evidencia disponible acerca de la introducción temprana de alimentos alergénicos y la posible protección en la aparición de alergia alimentaria en etapas posteriores. Métodos: Se realizó una revisión exploratoria de ensayos clínicos aleatorizados, cuya población de estudio incluyera lactantes menores de 6 meses al momento del reclutamiento con o sin diagnóstico de alergia alimentaria. Se incluyeron como alimentos potencialmente alergénicos el huevo, cacahuate y trigo. Se consultaron las bases de datos: Medline, EBSCO, OVID, Science Direct y JSTOR (Journal Storage), Scielo, LILACS, Redalyc e Imbiomed del mes de agosto a diciembre de 2021. Resultados: Se identificaron 429 artículos, se excluyeron 412 y el análisis final incluyó 9 estudios que cumplieron con los criterios de inclusión. Seis ensayos corresponden a alergia al huevo, dos al cacahuate y uno a trigo. La reducción del riesgo de alergia alimentaria se presentó en niños con riesgo de alergia. Las reacciones adversas fueron comunes, particularmente con la introducción de huevo. Conclusiones: No existe evidencia que la introducción temprana (< 6 meses de edad) de alimentos alergénicos reduzca el riesgo de alergia alimentaria en lactantes sin factores de riesgo.

Distributed energy resources (DER) such as solar photovoltaic (PV) interfaces with the utility grid by high-efficiency power electronic converters. This equipment is sometimes underutilized in terms of its power capacity; thus, the remaining capacity can be used to provide support to the distribution system. In this sense, this work assesses the performance of the three-level T-type quasi-impedance source inverter (3L-T-type qZSI) injecting not only active power to the grid, but also providing support to it by injecting reactive power and acting as an active power filter (APF) simultaneously. The global control strategy of the grid-connected inverter is derived from the instantaneous $i_{d}$ - $i_{q}$ power theory. The combination of an improved deadbeat current controller and a level-shifted carrier-based pulse-width-modulation (PWM) technique, using both the upper shoot-through (UST) and the lower shoot-through (LST) alternating states, allows a successful tracking of the current references. Both the dc-link voltage control and the neutral-point balancing are properly achieved by taking the advantage of the shoot-through (ST) states and the redundant states simultaneously. These control actions are implemented by simple proportional-integral (PI) controllers. The simulation and experimental results demonstrate the above-mentioned functionalities and verify the stability and good dynamic response of the grid-connected 3L-T-type qZSI.

Abstract Background Macrocystic lymphatic malformation is a rare benign skin disorder, especially the anogenital area, which covers less than .5% of the reported cases. It can cause vesicular and papular lesions on the face, trunk, extremities, and, less frequently, anogenital areas. Although there are currently several therapeutic options, surgical excision is the most widely used, considering the lowest recurrence rate. Case presentation In this article, we describe the case of a 15-year-old male patient who presented with herpetiform skin lesions, corresponding to the diagnosis of macrocystic lymphatic malformation, in the lower region of the right buttock. After confirmation of the diagnosis by histopathology, surgical excision was performed with a tensor fascia lata graft, with successful aesthetic and functional results. Conclusions Considering the diagnosis of macrocystic lymphatic malformation is of utmost importance, although its presence is unusual, to differentiate it from other herpetiform lesions. Despite the existence of multiple approaches today, definitive treatment with surgical extraction is necessary, both to improve the cosmetic aspect and to prevent associated complications. It is suggested that histopathological and imaging diagnostic tools be used as a routine element, in order to increase therapeutic success, as well as decrease the risk of recurrences. Evidence-based medicine ranking Level IV

Abstract Background Wild-type yeasts have been successfully used to obtain food products, yet their full potential as fermenting microorganisms for large-scale ethanol fuel production has to be determined. In this study, wild-type ethanologenic yeasts isolated from a secondary effluent were assessed for their capability to ferment saccharified microalgae sugars. Results Yeast species in wastewater were identified sequencing the Internal Transcribed Spacers 1 and 2 regions of the ribosomal cluster. Concurrently, microalgae biomass sugars were saccharified via acid hydrolysis, producing 5.0 ± 0.3 g L−1 of fermentable sugars. Glucose consumption and ethanol production of yeasts in hydrolyzed-microalgae liquor were tested at different initial sugar concentrations and fermentation time. The predominant ethanologenic yeast species was identified as Candida sp., and glucose consumption for this strain and S. cerevisiae achieved 75% and 87% of the initial concentration at optimal conditions, respectively. Relatively similar ethanol yields were determined for both species, achieving 0.45 ± 0.05 (S. cerevisiae) and 0.46 ± 0.05 g ethanol per g glucose (Candida sp.). Conclusion Overall, the results provide a first insight of the fermentation capacities of specific wild-type Candida species, and their potential role in ethanol industries seeking to improve their cost-efficiency.

Regarding the control of micro- and nanogrids, LC- or LCL-filtered power inverters (acting as interfaces with distributed energy resources such as photovoltaic or wind) commonly perform as grid-forming or grid-supporting units to maintain both the frequency and voltage within pre-set standards. Nevertheless, these power inverters are assumed to be connected at the same point of common coupling directly or via radial feeders; thus, the voltage references are the same for each parallel power inverter, thus requiring a virtual impedance loop. In addition, classic power sharing techniques comply with their individual power rates, and circulating currents among distributed generators are not considered. Under these circumstances, energy trading among prosumers and peer-to-peer contracts is not feasible in autonomous AC micro- and nanogrid operations. This paper proposes a reformulated power flow problem, adapted to autonomous droop-controlled AC microgrids, to be used as a secondary control layer. The entire hierarchical control is implemented and experimentally validated in a laboratory-scale nanogrid with energy storage systems, photovoltaic generators and power converters. The obtained results demonstrate the proper performance of the proposed approach, with successful operation of primary and inner controllers.

Microgrids/nanogrids of prosumers must be able to adapt to new business opportunities related to energy trading. Therefore, highly accepted hierarchical control strategies should be modified to allow deliberate energy interchange among prosumers, even when the microgrid they are integrated in, operates islanded. This is the main contribution of this paper, as energy exchange between prosumers is rarely addressed when they are islanded from the main grid. This work proposes a comprehensive hierarchical control strategy for a multibus nanogrid of prosumers, each of them having photovoltaic generation, battery energy storage systems and loads, in such a way that different voltage and power setpoints for each prosumer allow such energy interchange. Power flow inside the nanogrid is controlled to guarantee the technical feasibility of the obtained setpoints. The proposed control strategy is defined and experimentally validated in both islanded and grid-connected modes, by means of a laboratory-scale prototype. In addition, a smooth transition between the two modes is demonstrated. An adequate capability of the power converters to follow setpoints is proved, with acceptable transient behavior.

Although there is a growing interest in developing fast charging methods to enhance the Electric Vehicles’ appeal, the main energy supply is still the single-phase outlet. While single-phase charging may be simpler than three-phase, there are challenges in the integration of the propulsion and charging systems without adding inductive grid filters. Such integration would bring benefits like the simplification and reduction of components, costs, volume or weight. This can be achieved by using the windings of the propulsion machine as grid filters, but the use of the electric motor as a grid inductive filter leads to the generation of pulsating torque during the charging state. This translates into vibration, noise and eventually, damage to the motor and other components of the system. In this work, the authors propose a control strategy that considerably reduces the peaks of pulsating torque generated in any rotor position while using the machine wingdings as filter. Simulation tests have been carried out to validate the control strategy, taking into account the system efficiency. Finally, experiments are conducted to prove that the reduction of the torque pulsation is achieved.

A model for an equivalent electrical circuit designed for a ferrite (3C90) inductor usually used in power converters excited by a non-sinusoidal current appropriate for use in power electronics is proposed. This study, based on 3D finite element analysis, leads to significant precision advantages over 2D analysis for non-symmetric inductors. The frequency range of the analysis for the toroidal core was between 15 kHz and 1 GHz, with different levels of excitation in non-saturation and saturation status focusing on the power loss.

The Child Eating Behaviour Questionnaire (CEBQ) and the Adult Eating Behaviour Questionnaire (AEBQ) measure ‘food approach’ [Food responsiveness (FR); Emotional overeating (EOE); Enjoyment of food (EF); Desire to Drink] and ‘food avoidant’ [Satiety responsiveness (SR); Emotional undereating (EUE); Food fussiness (FF); Slowness in eating (SE)] appetitive traits (ATs) in children and adults, respectively. ‘Food approach’ traits predispose to overweight while ‘food avoidance’ traits provide protection, but little is known about the relationships between parents’ and their offspring’s ATs. The aim was to examine the associations between maternal and child appetitive traits, using the AEBQ-Esp and CEBQ-Mex adapted for use in Mexican populations. Sociodemographic data, weights and heights of mothers and their children (aged 3–13 years), who were recruited from a teaching hospital in Guadalajara, Mexico, were measured. Mothers completed both the AEBQ-Esp and the CEBQ-Mex. The CEBQ-Mex was developed, and its reliability was tested using Cronbach’s alpha and Omega, and Confirmatory Factor Analysis (CFA) was used to assess its validity. Pearson’s correlation coefficients were used to assess associations between mothers’ and children’s Ats. The sample included 842 mother-child dyads (mother’s mean age = 34.8±SD6.9 years, BMI 29.7±6.1 kg/m2; children’s mean age = 8.5 ±SD2.5 years, BMIz 1.5±1.6). Internal reliability was moderate to high [Cronbach alpha = .68-.86; Omega = .71-.87] for the CEBQ-Mex and validity was confirmed for an 8-factor model through CFA [RMSEA = 0.065; CFI = 0.840, NFI = 0.805; IFI = 0.842; and χ2(df = 532) = 2939.51, p < 0.001]. All but one of the children’s appetitive traits showed small to moderate, significant correlations with their mother’s counterpart [FR (r = .22; p.05). ATs tend to run in families, signalling the intergenerational transmission of eating behaviours. These may be useful targets for family-wide interventions to support the development and maintenance of healthy eating behaviours in childhood.

Several main methodologies are used to estimate the core power loss (CPL) in magnetic components. One group is based in the Steinmetz equation (The modified one, the generalized one and the natural equations are the principals). Another one is the separation of losses between hysteresis, eddy current and excess losses. The third group is based mathematical-empirical hysteresis models and the last one is based on the magnetization process. These approaches need a prior test or analysis to calculate the CPL. Tests are usually expensive, or the number of needed tests is excessive for the component design process. 2D analyses are not enough for some magnetic components due to their lack of symmetries. Toroidal core components are ones of the most common components in transformers and power converters. They do not have symmetries in the magnetic field distribution and only 3D models are satisfactory to take into account all the effects and phenomena. An extensive study of 3D model finite element analysis was developed to determine the main losses in magnetic components core, the hysteresis and eddy current losses. A new methodology is presented, per-unit CPL (considering only Hysteresis and Eddy Current Losses) that permits analyzing the impact of the involved factors separately. The proposed per-unit CPL allows the definition of a new equation for determining hysteresis and eddy current losses using only the geometrical and material parameters (core and coils) used to estimate the total CPL.

Smart transformers are considered a crucial part of future smart grids as they will operate as the energy router and be able to control the power flows from and to the microgrids since they are placed in the border. A multi-port transformer can integrate different energy resources, loads and energy storage systems, optimizing the power flows between these elements. Combining both concepts, a multi-port smart transformer is obtained that is able to integrate efficiently distributed and renewable energy resources, electric vehicle chargers, prosumers and energy storage in both AC and DC microgrids. Nevertheless, the operation of these transformers, composed of several modules connected in series to the high-voltage grid is not easy, mainly due to the different power consumed or generated by each module. In this paper this issue is analyzed and different operation strategies for coordinating the series-connected modules at the input side are studied by simulation. The paper will expose how it is possible to extend the proper operation of the system if a reactive power controller is implemented.

This paper presents a methodology for determining the optimal supply chain design with economic, environmental and risk management considerations. A multi-objective model based on mixed integer programming is proposed seeking three objectives: First, to minimize the total cost of transportation and the costs associated to the use of intermediate nodes. Second, to minimize the risks of product losses in transportation. Third, to minimize the environmental impact of CO2 emissions produced by transportation and storage operations. The proposed model is solved with two approaches: First, a commercial solver to compute the Pareto-optimal set of solutions. Second, a simulation-based optimization approach that allows to obtain statistically different but efficient solutions such that the decision-maker will be able to trade-off objectives while considering only Pareto optimal solutions. Experiments on random instances demonstrate the capability of the models and methods.

La clasificación de la vegetación usando información espectral multi-angular ha sido aproximada con esquemas de modelación restringidos o con hipótesis de homogeneidad o estacionariedad. En este trabajo se presenta un esquema de modelación global de los ángulos cenitales y acimutales en la reflectancia de la vegetación, extendiendo los desarrollos al caso de los efectos de cambios en las propiedades ópticas del fondo de la vegetación (suelos) y de la densidad de plantas (follaje). Esta síntesis se realiza en un espacio superior de compactación que depende esencialmente de dos parámetros y engloba todas las variaciones analizadas. El esquema de modelación global desarrollado se aplicó al caso de arreglos de plantas, diferentes densidades de ocho especies con arquetipos contrastantes y suelos desnudos. La modelación se aplicó a las mediciones de factores de reflectancia bi-cónicos, donde los ajustes resultaron óptimos (generalmente con R2 ≥ 0.99 y errores relativos medios menores al 7%). El análisis de los resultados mostró que la información espectral multi-angular para clasificación de especies, bajo condiciones generalizadas, mantiene todavía problemas de confusión en la discriminación de especies. Esto puede explicarse por la síntesis de análisis realizada de las variaciones asociadas a la discriminación.

En los bosques de coníferas de los estados de Puebla, Tlaxcala e Hidalgo, México se han registrado problemas de caída foliar, principalmente, por ataques de Lophodermium spp. Las alteraciones en las condiciones climáticas actuales tendrán un papel importante en la distribución futura del hongo. El objetivo del presente trabajo fue determinar la distribución potencial actual y con escenarios de cambio climático (CC) de Lophodermium spp. en la vegetación de las entidades antes mencionadas. Se aplicó el algoritmo Genetic Algorithm for Rule-set Production (GARP, por sus siglas en inglés) para generar los modelos potenciales de la distribución, a partir de diversas coberturas climáticas (actuales y escenarios de CC), y sitios de presencia del organismo. Los resultados sugieren que las áreas con alto potencial se ubican en la Sierra Norte de Puebla. La superficie de distribución potencial actual con categoría alta es mayor en el periodo de desarrollo (marzo-junio), 83 197 ha, con respecto a la fase de crecimiento (septiembre-diciembre), 74 829 ha. Con el escenario de CC, RCP4.5 (año 2039) la superficie con clase alta se presentó en el periodo de desarrollo, el cual fue de 159 433 ha; en contraste en el escenario RCP8.5 la extensión de la época de crecimiento fue superior, con un valor de 138 810 ha. La etapa de desarrollo del hongo en los escenarios actual y de CC RCP4.5 tuvo superficies con más potencial de presencia del organismo, y en la de crecimiento fue con el escenario RCP8.5.

Neck circumference was studied for the first time in a pediatric population in 2010. Since then, various countries have proposed cutoff values to identify overweight, obesity, and metabolic syndrome. However, no reference values have been established for the Mexican child population. The aim of this study is to provide percentile reference values for the neck circumference of Mexican schoolchildren. Only normal-weight schoolchildren aged 6–11 years were included. Percentiles and growth charts were constructed based on the “Generalized Additive Model for Location, Scale and Shape” (GAMLSS). A total of 1059 schoolchildren (52.9% female) was evaluated. Weight, height, and BMI values were higher for males; however, this difference was not statistically significant. The 50th percentile for females was 24.6 cm at six years old and 28.25 cm at 11 years old, and for males, it was 25.75 cm and 28.76 cm, respectively. Both males and females displayed a pronounced increase in neck circumference between 10 and 11 years of age. The greatest variability was found in the 11-year-old group, with an increase of 5.5 cm for males and 5.4 cm for females. This study presents the first reference values for neck circumference for a Mexican child population.

La nutrición adecuada durante los primeros dos años de vida es fundamental para el desarrollo pleno del potencial de cada ser humano; actualmente se reconoce que este periodo es una ventana crítica para la promoción de un crecimiento y desarrollo óptimos y un buen estado de salud. Por tanto, cumplir con una alimentación adecuada en esta etapa de la vida tiene impacto sobre la salud, estado de nutrición, crecimiento y desarrollo de los niños; no sólo en el corto plazo, sino en el mediano y largo plazo. El presente trabajo ofrece recomendaciones de alimentación complementaria (AC) que se presentan en forma de preguntas o enunciados que consideran temas importantes para quienes atienden niños durante esta etapa de la vida; por ejemplo: inicio de la alimentación complementaria a los 4 o 6 meses de edad; exposición a alimentos potencialmente alergénicos; introducción de bebidas azucaradas; uso de edulcorantes artificiales y productos light; secuencia de introducción de alimentos; modificaciones de consistencia de alimentos de acuerdo a la maduración neurológica; número de días para probar aceptación y tolerancia a los alimentos nuevos; cantidades por cada tiempo de comida; prácticas inadecuadas de alimentación complementaria; mitos y realidades de la alimentación complementaria; hitos del desarrollo; práctica del “Baby Led Weaning” y práctica de vegetarianismo.

This article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage at the load’s terminals and applies only six switches within the modulation period. The second proposal archives for less Total Harmonic Distortion (THD) of the generated load voltage. The third variant of modulation concerns maximizing the voltage transfer ratio, minimizing the number of switching, and the common-mode voltage cancellation. The discussed modulations are based on the concept of sinusoidal voltage quadrature signals, which can be an effective alternative to the classic space-vector approach. In the proposed approach, the geometrical arrangement of basic vectors needed to synthesize output voltages is built from the less number of vectors, which is equal to the number of the matrix converter’s terminals. The PWM duty cycle computation is performed using only a second-order determinant of the voltages coordinate matrix without using trigonometric functions. A new approach to the PWM duty cycles computing and the load voltage synthesis by 5 × 5 and 12 × 12 topologies has been verified using the PSIM simulation software.

In this paper, different Pulse Width Modulation (PWM) strategies for operating with a low-switching frequency, a topology that combines Conventional Matrix Converters (CMCs), and Coupled Reactors (CRs) are presented and discussed. The principles of the proposed strategies are first discussed by a conceptual analysis and later validated by simulation. The paper shows how the combination of CMCs and CRs could be of special interest for sharing the current among these converters’ modules, being possible to scale this solution to be a modular system. Therefore, the use of coupled reactors allows one to implement phase shifters that give the solution the ability to generate a stair-case load voltage with the desired power quality even the matrix converters are operated with a low-switching frequency close to the grid frequency. The papers also address how the volume and weight of the coupled reactors decrease with the growth of the fundamental output frequency, making this solution especially appropriate for high power applications that are supplied at high AC frequencies (for example, in airport terminals, where a supply of 400 Hz is required).

This manuscript explores fuzzy rule learning for sound synthesizer programming within the performative practice known as live coding. In this practice, sound synthesis algorithms are programmed in real time by means of source code. To facilitate this, one possibility is to automatically create variations out of a few synthesizer presets. However, the need for real-time feedback makes existent synthesizer programmers unfeasible to use. In addition, sometimes presets are created mid-performance and as such no benchmarks exist. Inductive rule learning has shown to be effective for creating real-time variations in such a scenario. However, logical IF-THEN rules do not cover the whole feature space. Here, we present an algorithm that extends IF-THEN rules to hyperrectangles, which are used as the cores of membership functions to create a map of the input space. To generalize the rules, the contradictions are solved by a maximum volume heuristics. The user controls the novelty-consistency balance with respect to the input data using the algorithm parameters. The algorithm was evaluated in live performances and by cross-validation using extrinsic-benchmarks and a dataset collected during user tests. The model’s accuracy achieves state-of-the-art results. This, together with the positive criticism received from live coders that tested our methodology, suggests that this is a promising approach.

Sensorless control of electrical drives is still a difficult task, especially in the lower speed region. Moreover, when the machine has a low saliency such as in the case of Surface Mounted Permanent Magnet Synchronous Motor (SMPMSM), high frequency injection techniques are even more challenging. In this paper, an enhanced demodulation algorithm for the sensorless control of a SMPMSM is proposed. The new scheme uses the high frequency injection in the Synchronous Reference Frame (SRF) and employs also the negative sequence content of the measured current for improved accuracy. This allows an improved performance with a lower amplitude of the injected signal, thus reducing the noise and additional losses in the motor. It is found that, by using both components with the algorithm developed the estimation ripple can be greatly reduced and the system can operate properly with a voltage injection of only 2.17% of the rated motor voltage, which is lower than most found in the literature, specially for low saliency machines. Simulations tests are carried out for the validation of the proposed method and experimental results in a 6.7 kW SMPMSM confirm its usefulness and correct operation with a reduced voltage injection, both in no-load and load conditions, for different low speeds, including start-up.

El trabajo refleja procedimientos asociados al diseño, modelación computacional y construcción de etapas de potencia en banda L empleando transistores de nitrito de Galio (HEMT GaN). En la ponencia se exponen, además, aspectos relacionados con simulación de procesos estáticos y dinámicos, acoplamientos de impedancias y polarización secuencial para los amplificadores de potencia basados en transistores de GaN dado al gran empleo que tiene en la actualidad para el desarrollo de las industrias como la automovilística y la aeronáutica, debido a las posibilidades y facilidades que brindan. Se incluyen resultados prácticos de construcción de una etapa de potencia de 5W con transistor de GaN.

Se desarrolló un secador solar directo con un diseño basado en dispositivos deshidratadores rudimentarios de uso regular, en granjas cacaoteras de Tabasco; con el objetivo de evaluar su desempeño en la obtención de cacao seco con- forme a la NMX-F-352-S-1980, mediante una exposición a luz solar durante cuatro días. Re- sultados: disminución paulatina del contenido de humedad hasta en un 7.50%, en promedio, en un producto con valor comercial a insertarse en el mercado.

Se presenta una experiencia multidisciplinar de innovación educativa y renovación metodológica cuyo objetivo ha sido la incorporación del enfoque pedagógico Flipped Classroom en el aula. La implementación de nuevas herramientas TIC durante el proceso educativo ha permitido garantizar el éxito de la experiencia. Se fundamenta en un proceso de investigación-acción en equipo docente interdisciplinar aplicado durante el curso 2015/16 sobre estudiantes de la Escuela de Ingeniería y Arquitectura y de la Facultad de Educación de la Universidad de Zaragoza. En las asignaturas se maneja diferente software y herramientas gratuitas mediante smartphones, tablets y ordenadores portátiles, analizando su repercusión. La actuación desarrollada resulta muy positiva para el alumnado, el profesorado y las asignaturas implicadas, siendo aplicables a diferentes contextos educativos.

Objective: To demonstrate that a nutritional support intervention, via naso-enteral tube-feeding or gastrostomy, has a significant impact on the nutritional status and body composition in severely malnourished children with cerebral palsy spastic quadriplegia Methods: Thirteen patients with moderate/severe malnutrition and cerebral palsy spastic quadriplegia who were fed via naso-enteral tube-feeding or gastrostomy were included in a cohort study. Anthropometric measurements and estimated body composition by bioelectric impedance analysis were obtained. ANOVA and Wilcoxon tests were used. Results: During the four weeks of nutritional recovery, an average weight increase of 2700 g was achieved. There were significant increases in anthropometric indicators, including BMI and weight/length (p < 0.01). The increase in arm fat area was significantly higher than the increase in arm muscle area (104.5 vs 17.5%). Conclusion: Intensive nutritional support for four weeks had a significant effect on the nutritional status and body composition of severe and moderately malnourished children with cerebral palsy spastic quadriplegia.

Based on the assumption that vehicles served by petrol stations will be replaced by Electric Vehicles (EV) in the future, EV public charging station facilities, with off-board fast chargers, will be progressively built. The power demand of these installations is expected to cause great impact on the grid, not only in terms of peak power demanded but also in terms of power quality, because most battery chargers behave as non-linear loads. This paper presents the proposal of a novel comprehensive global control strategy for the power electronic converters associated with bidirectional three-phase EV off-board fast chargers. The Charging Station facility Energy Management System (CS-EMS) sends to each individual fast charger the active and reactive power setpoints. Besides, in case the charger has available capacity, it is assigned to compensate a fraction of the harmonic current demanded by other loads at the charging facility. The proposed approach works well under distorted and unbalanced grid voltages. Its implementation results in improvement in the power quality of each fast charger, which contributes to improvement in the power quality at the charging station facility level, which can even provide ancillary services to the distribution network. Simulation tests are conducted, using a 100 kW power electronic converter model, under different load and grid conditions, to validate the effectiveness and the applicability of the proposed control strategy.

The proliferation of residential photovoltaic (PV) prosumers leads to detrimental impacts on the low-voltage (LV) distribution network operation such as reverse power flow, voltage fluctuations and voltage imbalances. This is due to the fact that the strategies for the PV inverters are usually designed to obtain the maximum energy from the panels. The most recent approach to these issues involves new inverter-based solutions. This paper proposes a novel comprehensive control strategy for the power electronic converters associated with PV installations to improve the operational performance of a four-wire LV distribution network. The objectives are to try to balance the currents demanded by consumers and to compensate the reactive power demanded by them at the expense of the remaining converters’ capacity. The strategy is implemented in each consumer installation, constituting a decentralized or distributed control and allowing its practical implementation based on local measurements. The algorithms were tested, in a yearly simulation horizon, on a typical Portuguese LV network to verify the impact of the high integration of the renewable energy sources in the network and the effectiveness and applicability of the proposed approach.

Microgrids of prosumers are a trendy approach within the smart grid concept, as a way to increase distributed renewable energy penetration within power systems in an efficient and sustainable way. Single prosumer individual management has been previously discussed in literature, usually based on economic profit optimization. In this paper, two novel approaches are proposed: firstly, a different objective function, relative to the mismatch between generated and demanded power, is tested and compared to classical objective function based on energy price, by means of a genetic algorithm method; secondly, this optimization procedure is applied to batteries’ coordinated scheduling of all the prosumers composing a community, instead of single one, which better matches the microgrid concept. These approaches are tested on a microgrid with two household prosumers, in the context of Spanish regulation for self-consumption. Results show noticeably better performance of mismatch objective function and coordinated schedule, in terms of self-consumption and self-sufficiency rates, power and energy interchanges with the main grid, battery degradation and even economic benefits.

The expected increase in the penetration of electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) will produce unbalanced conditions, reactive power consumption and current harmonics drawn by the battery charging equipment, causing a great impact on the power quality of the future smart grid. A single-phase semi-fast electric vehicle battery charger is proposed in this paper. This ac on-board charging equipment can operate in grid-to-vehicle (G2V) mode, and also in vehicle-to-grid (V2G) mode, transferring the battery energy to the grid when the vehicle is parked. The charger is controlled with a Perfect Harmonic Cancellation (PHC) strategy, contributing to improve the grid power quality, since the current demanded or injected has no harmonic content and a high power factor. Hall-effect current and voltage transducers have been used in the sensor stage to carry out this control strategy. Experimental results with a laboratory prototype are presented.

El propósito del estudio fue evaluar el estado nutricio de vitamina A en preescolares con padecimientos oculares que acuden al Hospital Civil de Guadalajara. En estudio transversal analítico se incluyeron por conveniencia 100 sujetos (24-71 meses) con padecimiento ocular. El consumo de vitamina A (VA), energía y macro nutrimentos se estimó con una encuesta dietética de recordatorio de 24 horas (EDR-24h). Mediante cromatografía líquida de alta presión (HPLC) se determinó la concentración sérica de retinol y se realizó una citología de impresión conjuntival (CIC) por un patólogo entrenado en la técnica. Se estimaron los índices talla/edad y peso/talla (Puntaje z) y se utilizaron las pruebas de ANOVA, U de Mann Whitney y de correlación de Spearman. Fueron niñas 44,1% y varones 55.9%. Los padecimientos oculares más frecuentes fueron: estrabismo (41,9%), conjuntivitis (19,4%) y padecimientos congénitos (17,2%). Según la EDR-24 h el consumo de vitamina A fue de 374 µg/día ± 706; la concentración de Retinol sérico 30 µg/dL ± 7,6 y CIC fue normal en 75,6%. Sólo 3.2% a 3,5% presentaron deficiencia de VA (concentración de retinol y CIC). No hubo asociación entre padecimientos oculares y deficiencia de VA. Hubo correlación positiva entre consumo de vitamina A e índice peso/talla (r = 0,244). En conclusión, la mayoría de los preescolares cubrió la ingestión recomendada de vitamina A, la deficiencia de esta vitamina fue baja y no se asoció a padecimientos oculares.SUMMARY The purpose was to evaluate the nutritional status of vitamin A in preschool children with ocular diseases attending to the Hospital Civil of Guadalajara. In a cross sectional design 100 preschool children between 24 and 71 mo of age with ocular diseases were included. Vitamin A intake was evaluated by 24 h dietetic recall, plasma Retinol concentration by high pressure liquid chromatography (HPLC); and, conjunctiva impression cytology (CIC) was carried out by a trained pathologist. ANOVA and U Mann Whitney tests, and also Spearman correlations were estimated. There were 44.1% females and 55,9% males. Strabismus was the most common disease (41,9%), conjunctivitis (19,4%), and congenital diseases (17,2%). The mean intake of Vitamin A was 374 µg/d ± 706 and the serum concentration of retinol was of 30 µg/dL ± 7,6; CIC was normal in 75,6%. The percentage of vitamin A deficiency was 3,2% according to the serum concentration of Retinol and 3,5% to the CIC criteria. It was not association between the nutritional status of vitamin A and ocular diseases. A positive correlation between vitamin A intake and weight/height index (r = 0,244) was found. In conclusion, most preschool children covered the dietary reference intake recommendation of vitamin A; deficiency of this vitamin was lower and, it was not associated to ocular diseases.

El propósito fue identificar los factores asociados a retraso en el crecimiento en niños de una región semi-rural en Arandas, Jalisco, México. En estudio transversal analítico se incluyeron 432 niños de 12 a 120 meses. Se analizaron variables sociales, demográficas, económicas, dietéticas y patológicas. Se utilizó la puntuación Z del índice talla/edad (< -1 DE y < - 2 DE) para evaluar el déficit de crecimiento. Con la prueba de chi cuadrada y la razón de momios (IC 95%) se estimaron los factores de riesgo y protección. Los factores de riesgo fueron: > tres niños en la familia [RM 1.71 (1.01, 2.87)], consumo de sodas azucaradas > 4 veces por semana [RM 2.36 (1.19-4.73), ingreso familiar mensual < 200 USA dólares [RM 3.5 (1.28, 9.76)] y gasto per cápita en alimentación < 10% de un salario mínimo (100 USA dólares al mes) [RM 1.81 (1.06, 3.09)]; edad < 24 meses [RM 2.02 (1.09, 3.75)], adición de azúcar al biberón [RM 8.56 (1.84, 54.9)], modificación de la dieta durante la diarrea [RM 2.40 (1.02, 5.77)] ingestión de leche < 4 veces a la semana [RM 2.71 (1.55, 4.73)] y casi significativo: consumo de frijoles [RM 1.75 (0.98, 3.13)]. Factores de protección: familia nuclear [RM 0.28 (0.09, 0.85)] y dilución adecuada de la fórmula de alimentación [RM 0.71 (0.60, 0.85)]. En el modelo de regresión los factores de riesgo fueron: consumo de sodas, frijoles y adición de azúcar u otros edulcorantes al biberón.The purpose was to identify risk factors associated to deficit on linear growth in children from a semi-rural population in Arandas, Jalisco, Mexico. In a cross sectional study 432 children, 12 to 120 months old were included. Social, demographic, economical, dietetic and pathological characteristics and deficit in the height /age index (< - 1 and - 2 z score) were considered. A chi square test and Odds Ratio (CI 95%) to identify the risk and protection factors were also obtained. Risk factors for height/age deficit were: > 3 children in the family [OR 1.71 (1.01, 2.87)], soft drinks consumption > 4 times a week [OR 2.36 (1.19-4.73)], family’s monthly income < 200 USA dollars [OR 3.5 (1.28, 9.76)] and per capita food expenses < 10% of a minimum salary (100 USA dollars a month) [OR 1.81 (1.06, 3.09)]; age < 24 months [OR 2.02 (1.09, 3.75)], adding sweeteners to the bottle [OR 8.56 (1.84, 54.9)], diet modification during diarrhea [OR 2.40 (1.02, 5.77)], milk intake < 4 times a week [OR 2.71 (1.55, 4.73)] and nearly significant, bean consumption [1.75 (0.98, 3.13). Protection factors: nuclear family [OR 0.28 (0.09, 0.85)] and an adequate infant formula dilution [OR 0.71 (0.60, 0.85)]. In multivariate models associated factors to deficit of height were higher consumption of soft drinks, beans and the addition of sweeteners to the bottle. In addition to socioeconomic variables, lower consumption of high quality food and proteins and higher intake of legumes were important risk factors for mild and moderate deficit height/age.

El niño con desnutrición grave tiene una disfunción de la respuesta inmune que puede aumentar de manera significativa la morbilidad y la mortalidad por infecciones. Por ello, el objetivo del presente estudio fue demostrar el efecto del apoyo nutricio intensivo en la concentración en suero y celular de IL-2 y sub-poblaciones de células CD4+, y CD8+ T en niños con desnutrición proteínico-energética grave. En un ensayo clínico se incluyeron 10 niños con desnutrición primaria grave, menores de 48 meses de edad, quienes recibieron una fórmula sin lactosa por alimentación enteral continua por dos semanas y dos semanas más ad libitum. Se obtuvieron la concentración sérica y celular de IL-2 y las sub-poblaciones de linfocitos CD4+ y CD8+ en los casos y en un grupo control (n = 13). Con la prueba t de student pareada se compararon los valores inicial vs. final de los sujetos y se utilizó la prueba U-Mann-Whitney para la comparación con el grupo control. Se rechazó la hipótesis nula con una p < 0,05. Se observó un incremento notable inicial vs. final en el porcentaje de expresión celular de IL-2 (p < 0,001) y en la concentración sérica de esta citocina (p = 0,001). Por tanto, cuatro semanas de apoyo nutricio intensivo fueron suficientes para mostrar un incremento significativo en la producción de IL-2, independientemente de los nutrimentos involucrados, aunque aparentemente este incremento dependió de la gravedad de la DPE.Effect of the nutritional recovery on the concentration of Interleukin-2 in severely malnourished children. The severely malnourished child has dysfunction of the immune response that may increase the risk of morbidity or mortality due to infectious diseases, therefore, the purpose of this study was to demonstrate the effect of intensive nutritional support on the cellular and serum concentration of IL-2 and CD4+, as well as CD8+ T cells in children with severe protein energy malnutrition. A clinical assay was carried out in a tertiary care hospital. 10 severely malnourished children < 48 months of age who received formula without lactose via enteral feeding for two weeks and ad libitum for an additional two weeks were included. Cellular and serum concentrations of IL- 2 and the subpopulation of CD4+ and CD8+ were obtained. A control group (n = 13) was included. A paired student t test for initial-final determinations and the Mann-Whitney Test for comparison with control group were used, and null hypothesis was rejected with a p value < 0,05. There was a noteworthy increase in the comparison between the initial vs. final percentage of the cellular expression of IL-2 (p < 0,001) and in the serum concentration of IL-2 (p = 0,001). Therefore, four weeks of nutritional recovery significantly restored the production of IL-2, independently of the nutrients involved in the process, although, the rate of restoration seems to depend on the severity of the children primary PEM.

El propósito fue identificar hábitos de alimentación en adolescentes embarazadas y sus conceptos culturales con mayor influencia. Se estudiaron 54 sujetos de 12 a 19 años de edad de la ciudad de Guadalajara, se obtuvieron datos socioeconómicos, dietéticos, frecuencia de consumo de alimentos y se exploraron sus conceptos culturales en alimentación; con prueba chi cuadrado se estimó la asociación entre variables. El consumo de grasas fue bajo en adolescentes tardías vs. temprana/media 57 vs. 71 g/d (p = 0,05), el de hierro, calcio y zinc fue deficiente en la etapa temprana/media, mientras que el de ácido fólico fue muy bajo en la etapa tardía. La tortilla de maíz fue el cereal y alimento más consumido (93-96%). Las frituras y refrescos (62 y 55%) prevalecieron en la etapa temprana/media. De las costumbres locales, los tacos, pozole y hamburguesas fueron los más referidos (74,1%). Refirieron perjudiciales a las grasas (36,7%), “comida chatarra” (30%), chile (26,7%), refrescos embotellados (23,3%), comidas preparadas (26,7%) y sal (10%). Creían que las verduras (77%), frutas (60%), leche (21%), caldos (17%) y carnes (12,5%) eran benéficos durante el embarazo. 96% consideraba que los caldos de pollo y de frijol eran nutritivos (mito) y que había alimentos prohibidos (tabúes) durante el embarazo: chile (48%), “producto” chatarra (20%) y sal (16%). El prejuicio fue más común en adolescentes tardías (60.9%) (p = 0,03]. Los hábitos de alimentación erráticos y la confusión conceptual propician una ingestión baja de nutrimentos y colocan a estas adolescentes embarazadas en riesgo nutricio.The purpose of this study was to identify the food habits of pregnant adolescents and their perception about which, of her cultural concepts, have higher influence. 54 subjects between 12 and 19 years old from Guadalajara City were included and socioeconomic, dietetic data, as food frequency consumption and cultural concepts about feeding were also explored. Chi square was used for identifying association between variables. The fat intake was lower in late vs. Early and middle stage of adolescence (57 vs. 71 g/d, p = 0.05). The iron, calcium and zinc intake was also deficient in the early/middle stage; meanwhile, the folic acid consumption was very low in the late stage of adolescence. Corn tortillas were the most consumed cereal and food (93-96%); junk food and sodas (62 and 55%) prevailed in the early/middle stage. About local costumes, “tacos”, “pozole” and burgers were the most referred (74,1%). They also mentioned that fat (36,7%), junk food (30%), chili (26,7%), sodas (23,3%), processed meals (26,7%) and salt (10%) were harmful. They also believed that vegetables (77%), fruits (60 %), milk (21%), broths (17%), and meat (12,5%) were beneficial; and, 96% considered that chicken and bean broths were nutritious (myth). There were some prohibited foods (taboos) during pregnancy: chili (48%), junk food (20%), and salt (16%). Prejudices were more common among later adolescents (60,9%) (p = 0.03). The erratic food habits and the conceptual confusion of these adolescents cause a low intake of nutrients and place them in a nutritional risk.

OBJETIVO: Evaluar el riesgo de dislipidemia asociado a obesidad en niños y adolescentes. MATERIAL Y MÉTODOS: En un estudio transversal analítico se incluyeron 62 niños y adolescentes obesos (IMC > centila 95 y pliegue cutáneo tricipital > centila 90) y 70 no obesos (IMC centilas 5-85), con edades de 5 a 15 años, sin enfermedades crónicas. Se investigaron características personales y antecedentes familiares de enfermedades crónicas y se determinó el perfil sérico de lípidos. Se calculó el riesgo de presentar alteraciones en el perfil sérico de lípidos en niños con obesidad mediante la razón de momios (RM) y se realizó análisis multivariado. RESULTADOS: La edad promedio para todo el grupo fue de 9.8 ± 2.7 años; 63 individuos eran del sexo femenino y 69 del masculino. La presencia de obesidad se asoció a riesgo de valores anormales de colesterol, triglicéridos, LDL, HDL y dislipidemia (>1 valor anormal) (RM 4.47-15.0). En obesos el análisis multivariado mostró que la pertenencia al sexo femenino se asoció significativamente a dislipidemia. CONCLUSIONES: La obesidad en niños y adolescentes se asocia a riesgo elevado de presentar dislipidemia; este riesgo es mayor en las mujeres.OBJECTIVE: To assess the risk of dislypidemia associated with obesity in children and adolescents. MATERIAL AND METHODS: A cross sectional study was conducted with 62 obese children (BMI > 95 centile and tricipital skinfold thickness > 90 centile) and 70 non-obese children (BMI 5-85 centile) ages 5-15 years, without chronic diseases. Subjects' characteristics and family background of chronic diseases were collected and a lipid profile was determined. The risk of lipid alterations in the obese children was calculated using odds ratio (OR) and multivariate analysis. RESULTS: Mean age was 9.8 ± 2.7 years in both groups; 63 girls and 69 boys were included. Obesity was associated with abnormal values for cholesterol, triglycerides, LDL, HDL and dislypidemia (> 1 abnormal value) (OR 4.47-15.0). In obese children and adolescents the multivariate analysis showed that female gender was associated with dislypidemia. CONCLUSION: Obesity in children and adolescents is associated with high risk of dislypidemia; the risk is higher among females.

Objetivo. Estimar la prevalencia de deficiencia de hierro, yodo y parasitosis en niños que asisten al Instituto Alteño para el Desarrollo de Jalisco (Inadej), Arandas, Jalisco, México. Material y métodos. Estudio transversal efectuado entre 1997 y 1999 con 432 niños de 12 a 120 meses de edad, de nuevo ingreso al Inadej. Se determinaron variables hematológicas, yodo en orina y presencia de parásitos. Se utilizaron las pruebas Ji cuadrada y t de Student en variables no paramétricas y paramétricas. Resultados. Hubo más anemia (20 vs 7.4% p=0.007) y deficiencia de hierro (60.9 vs 44.4% p=0.02) en prescolares que en escolares. El 29% presentaron deficiencia de yodo (10.5% moderada o grave) y 47.2% parasitosis. Predominaron G. lamblia y E. histolytica. Bajo salario, sexo masculino y no tener seguridad social se asociaron con parasitosis. Conclusiones. La elevada prevalencia de deficiencia de hierro, yodo y parasitosis obliga al sector salud estatal a ejecutar medidas eficaces para abatir estas enfermedades prevenibles.Objective. To estimate the prevalence of iron deficiency, iodine deficiency and parasitosis in children attending the Instituto Alteño para el Desarrollo de Jalisco ((Highlands Institute for Development of Jalisco State, INADEJ), Arandas, Jalisco, Mexico. Material and Methods. A cross-sectional study was conducted between 1997 and 1999, among 432 children aged 12 to 120 months attending the INADEJ. Measurements included hematological values, urine iodine concentration, and presence of parasites. Student's t test chi square tests were used for parametric and non-parametric analysis. Results. The prevalence figures of anemia (20 vs 7.4%, p=0.007) and iron deficiency (60.9 vs 44.4%, p=0.02) were higher in preschool than in school children. Iodine deficiency was found in 29% (10.5% moderate or severe) and parasitosis in 47.2% of children, mainly E. histolytica (30.2%) and G. lamblia (28.9%). Low income, male gender and lack of social security policy holding were associated to parasitosis. Conclusions. The high prevalence rates of iron deficiency, iodine deficiency, and parasitosis, should be addressed by state health services with effective interventions to restrain these preventable diseases.

Objetivo. Valorar el estado de nutrición de niños que asisten al Instituto Alteño para el Desarrollo de Jalisco en Arandas, Jalisco, y discutir los criterios de clasificación de la desnutrición en México. Material y métodos. Estudio transversal, desarrollado con 775 niños de 12 a 120 meses de edad y que asisten al Instituto Alteño para el Desarrollo de Jalisco (Inadej) y 432 encuestas a niños de nuevo ingreso al Inadej. Se calcularon los índices peso/edad, talla/edad y peso/talla, y se investigaron características sociodemográficas y económicas y hábitos de alimentación; asimismo se compararon los criterios de la Organización Mundial de la Salud (OMS) y de la Norma Oficial Mexicana (NOM-SSA) para definir la prevalencia de desnutrición. Resultados. Hubo baja escolaridad en ambos padres (3.6 años). El ingreso familiar fue de $198 dólares mensuales y cada miembro recibió 0.56 dólar/día para las tres comidas. La prevalencia de desnutrición fue mayor en los tres índices con el uso de la NOM-SSA que con el criterio de la OMS (peso/edad 91.7 vs. 30.9%; talla/edad 66.9 vs. 17.3%; peso/talla 62.5 vs. 9.5% respectivamente). Conclusiones. El índice peso/edad y la NOM SSA sobrestiman la prevalencia de desnutrición y no discriminan entre niños genéticamente pequeños, con desnutrición aguda o desnutrición crónica o pasada. Es más útil el criterio de la OMS. Se deben incluir los índices peso/talla (desnutrición reciente) y talla/edad (desnutrición crónica) para comparación internacional.Objective. To assess the nutritional status of children attending the Instituto Alteño para el Desarrollo de Jalisco (Highlands Institute for Development of Jalisco State, Inadej) in Arandas, Jalisco and to discuss the classification criteria of infant malnutrition in Mexico. Material and Methods. A cross-sectional study was conducted in 775 children aged between twelve and one hundred and twenty months, who attended Inadej, including 432 children recently registered in INADEJ. Measurements included weight/age, height/age, and weight/height indices. The prevalence of malnutrition was compared using the WHO's criteria and the Mexican Official Norm Classification (NOM-SSA) criteria. The weight/age, height/age and weight/ height indices were compared using the chi-squared test. Results. Parents' schooling level was low (mean=3.6 years); the mean family income was U.S. $198.00 dollars per month, with each family member receiving 0.56 dollars per day for three daily meals. The prevalence of malnutrition was significantly higher with any of the three indices when using the NOM-SSA criteria, as compared to the WHO criteria (weight/age 91.7 vs. 30.9%; height/age 66.9 vs 17.3%; and weight/height 62.5 vs. 9.5%, respectively). Conclusions. The weight/age index and the NOM-SSA criteria overestimate the prevalence of malnutrition and are not able to tell apart children with familial small size, nor those with acute and/or chronic or past malnutrition. The WHO criteria were found to be more useful; the weight/height (recent malnutrition) and height/age (chronic malnutrition) indices should be used for international comparisons.