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This paper focuses on the control design of DC-DC converters delivering power into energy distribution networks. The scenario where the destabilizers of the system called constant power loads (CPLs) are presented. The idea of the proposed scheme is to take advantage of the so-called persistency of excitation conditions, which is used to elaborate a controller without the need for large mathematical models. The proposed data-driven approach can guarantee stability by solving a set of Lyapunov Linear Matrix Inequalities (LMIs). The stabilizing control scheme was designed using the linear difference systems and quadratic difference forms (QdF) concepts of behavioral system theory. Besides, a comparison between simulation and experimental results are presented to validate the theoretical design and illustrate the benefits of this scheme.

In this paper is studied and presented the solution for the instability problem caused by the interconnection of DC converters with constant power loads (CPLs). A linear and a nonlinear energy-based approaches are proposed. Without the presence of CPLs, the stability of the DC-DC power converter is intrinsic, while with CPLs the stability must be induced, a task that is not easy with traditional control approaches. This paper shows that the stabilization of the power converter can be achieved in pure physical terms, using power and energy as the primary objectives, which can be done in a linear and a nonlinear approach. Also, considering the energy as the perspective for the problem provides a physical explanation to the stability issues, furthermore, it provides a clear practical solution, because now it is possible to link the parameters of the controller to nominal specifications that are used for power converter design. In this way, the strategies based on the power and energy are now based on known approaches, which is a difference to known approaches, whose stability are based on frequency domain, eigenvalue and immittance criteria. Experimental results are presented to corroborate the theoretical analysis.

Traditional fermentations have been widely studied from the microbiological point of view, but little is known from the functional perspective. In this work, nitrogen fixation by free-living nitrogen-fixing bacteria was conclusively demonstrated in pozol, a traditional Mayan beverage prepared with nixtamalized and fermented maize dough. Three aspects of nitrogen fixation were investigated to ensure that fixation actually happens in the dough: (i) the detection of acetylene reduction activity directly in the substrate, (ii) the presence of potential diazotrophs, and (iii) an in situ increase in acetylene reduction by inoculation with one of the microorganisms isolated from the dough. Three genera were identified by sequencing the 16S rRNA and nifH genes as Kosakonia, Klebsiella, and Enterobacter, and their ability to fix nitrogen was confirmed. IMPORTANCE Nitrogen-fixing bacteria are found in different niches, as symbionts in plants, in the intestinal microbiome of several insects, and as free-living microorganisms. Their use in agriculture for plant growth promotion via biological nitrogen fixation has been extensively reported. This work demonstrates the ecological and functional importance that these bacteria can have in food fermentations, reevaluating the presence of these genera as an element that enriches the nutritional value of the dough.

This paper introduces a novel modeling approach for short-circuit studies incorporating superconducting fault current limiters (ScFCLs). The conventional formulation for short circuit studies, based on symmetrical components, has been extended to include the nonlinear limiting features of the ScFCL. Indeed, this is a novel iterative modeling method that has been derived from the classical calculations of short circuits. The operating point of the ScFCL is computed in the abc reference frame, while the solution of the whole network, including all of its components, is achieved using symmetrical components. The ScFCL model, which includes various parallel-connected superconducting tapes, is derived for the positive, negative, and zero sequences. Given that the resistance of the ScFCL is nonlinear and depends on the current flow, an iterative process is used to carry out short-circuit calculations. To validate the proposed method, radial and meshed distribution networks were studied. The solutions derived from the proposed approach and the ones obtained from the electromagnetic transient software Alternative Transients Program-Electromagnetic Transients Program were compared with both solutions agreeing very well with each other. The standard IEEE 14-bus test system, slightly modified to include two ScFCLs, was additionally simulated to demonstrate the practicality of the new approach in larger networks.

This study deals with the faults' detection and classification in AC transmission lines based on power spectral density (PSD), introducing PSD in time and frequency for analysing transient information under faulted conditions. The discrete wavelet transform is used for scaling current signals in time-frequency at different decomposition levels by approximation and detail coefficients. Then, a wavelet-covariance matrix is shaped with the aim to obtain its PSD, being this the key to detect and classifying faults. Results show that the proposed method attains the detection in a short time and the classification is accomplished via the Hellinger distance, whose straightforward implementation is carried out in this study. The classification process is compared adopting different classifiers to cope with a set of signals in a time frame. Finally, the proposal is extensively assessed using real and simulated signals stemming from multiple fault cases of radial and interconnected power grids.

Background: The ACGME instituted duty hour restrictions in 2003, necessitating re-organization and re-structuring of resident schedules and educational opportunities. In response, many programs created night float rotations. After noting decreased resident attendance at conferences and didactics with this model, our institution implemented interventions to offer teaching overnight. These teaching initiatives have evolved significantly over time; however, resident perception of their impact has not been evaluated. Thus, our primary objective was to evaluate resident perception of an evening curriculum focused on acute management of common overnight issues. Our secondary objective was to explore how nocturnal education has evolved and elucidate factors …

Distribution networks are currently the main focus of modernization in electric power systems. For instance, to deal with emerging and increasingly challenging scenarios (e.g., high penetration of renewables, distributed generation, electric vehicle proliferation, etc.), new smart grid technologies are being deployed over distribution networks. This is the case of micro phasor measurement units ( μ PMUs), which can be seen as a modern high-precision version of the legacy transmission system PMU. Motivated by the benefits, as well as the costs associated with μ PMU deployment, in this work we introduce a new methodology to determine optimal μ PMU placement, considering grid topology changes. Firstly, a technique to minimize power losses across the grid by changing its topology is presented. Afterward, a technique to estimate the grid states – full numerical observability – with the minimum number of μ PMUs is disclosed, introducing the concept of bus “virtualization” through pseudo-measurements. This work is based on a multi-objective approach, acting on genetic algorithms, and validated over a distribution network with a variant structure, which is optimally instrumented. It is shown that the proposed methodology can maintain low approximation errors despite topology variations. Also, the virtualization approach enables full numerical observability even when using fewer measurement units, i.e., the observability constraint is eliminated and the number of μ PMUs can be solely related to the estimation error.

This work proposes a new method based on the Hermite transform with the aim of identifying transient events in power transformers caused by energizations and current transformer (CT) saturation. The Hermite transform is a signal processing technique that allows the representation of signals in the time–frequency domain as well as at multiple resolution levels. Gaussian derivatives analyze the signals in the proposed scheme according to the Hermite transform theory. The newly introduced approach is based on a differential scheme considering three functions, the first one to analyze the positive half-cycle and the second one for the negative half-cycle. The latter is a new blocking function for the detection of transient conditions, that is, the operation command is disabled; otherwise, the third function will confirm if the condition is an internal fault. To validate the performance of the proposed method, several fault conditions are addressed, such as load switching, internal and external faults, current transformer saturation, and single-phase-to-ground faults. Results show the effectiveness of the proposed method, which improves the differential protection performance to discriminate transient conditions from internal faults.

This paper presents a protection scheme for alternating current transmission lines based on the traveling wave propagation. The analyzed protection scheme uses measurements in only one terminal by using the distributed parameter theory. The method analyzes the fault location using the correlation between two traveling waves, backward and forward waves. Results demonstrate that the correlation method can accurately estimate the fault distance, and this is carried out by using the first two wavefronts of the arrived signals at the measurement terminal. The algorithm is validated through the IEEE 9-bus test system, considering different faults simulated in the software ATP-EMTP. The studied method’s effectiveness is assessed and compared with the MODWT, showing both techniques good results for the fault location process.

This paper introduces a novel approach to detect and locate faults in AC transmission lines. The fault location process is carried out using wavelet correlation modes and taking into account the short-circuit theory. To validate the new proposal, several tests were conducted in ATP-EMTP software considering a wide variety of simulations. Additionally, the fault location is done using a new mother wavelet, called wavelet ET that was previously obtained considering the transient information produced by switching transients and faults. The obtained results shows satisfactory during the fault location process which is analyzed in a multi-terminal transmission line. The mean error achieved was lower than 1 % for solid-grounded faults.

An approach to solve the limitations of autologous bone grafting procedures in bone injury treatment is to develop bioactive coatings in the implantation system. The objective of this work is to compare the temperature effect on the stability of hydroxyapatite, graphene, and collagen colloidal suspensions to be used as biocompatible and bioactive coatings on a carbon fiber composite surface. Synthesized hydroxyapatite was assessed by X-ray diffraction. Zeta potential at different temperatures was evaluated. Specimens were characterized using scanning electron microscopy and Raman analysis. The results showed that the best hydroxyapatite/graphene ratio was 85/15, while those of the hydroxyapatite/collagen mixtures were 85/15. A hydroxyapatite/graphene/collagen mixture was synthesized based on these results.

This paper proposes a new time-domain method for fault detection and location in alternating current multi-terminal transmission lines based on wavelet analysis called wavelet correlation modes. Power system protection of multi-terminal transmission lines is a complex task because the infeed effect may affect its performance. The proposed algorithm based on one-terminal measurements enhances the detection time and diminishes the error of the fault location. This approach suits the protection scheme to attain reliable and accurate performance when any fault type is presented at different locations along the transmission line. The applicability of this proposal is validated under different fault scenarios and compared against conventional protection algorithms. The proposed algorithm is implemented in MATLAB software, and all simulations are conducted in the Alternative Transients Program of the Electromagnetic Transients Program (ATP/EMTP) software. The presented results confirm the main advantages of this approach. The new introduced method is tested under different mother wavelets to estimate the fault location.

In this study, a new algorithm for discrimination between internal faults and inrush current conditions in power transformers is presented. First, the proposed algorithm removes the pre-fault conditions of the fault currents. Then, those currents are processed using the discrete wavelet transform to obtain the wavelet matrix. The correlation matrix is computed from wavelet matrix to know the eigenvalues associated with each frequency scale and to reduce the analysed information. This algorithm, which the authors are going to call wavelet correlation modes, is used to identify inrush and internal fault currents in power transformer. To validate the proposed algorithm, simulations are carried out in power systems computer-aided design software, and the obtained signals are analysed in order to evaluate its performance and sensitivity.

A new algorithm to partial discharges (PD) location in transformer windings by means of the discrete wavelets transform (DWT) and the Kullback-Leibler (KL) divergence is presented. When the insulation system of transformers has considerable damage, high levels of PD appear. A PD analysis will help to prevent and to avoid catastrophic faults in the transformer insulation system, and is also useful to quantify the damage level into it. However, it is a complex task, because PD signals have a small magnitude and are presented during some microseconds. In this paper, a lumped parameter model RLC is used to model the transformer winding and to obtain PD reference signals. The DWT is used to process those signals. PD location is finally estimated by means of the minimum entropy concept that minimizes the Kullback-Leibler (KL) divergence between PD signals (test and reference signals). Different time durations and amplitudes to the PD signals were considered. The results of computer simulation confirm the accuracy of the proposed algorithm, with an error less than 5%. Also, the algorithm is validated in a distribution transformer winding. Fil: Guillen, Daniel. Universidad Autónoma de Nuevo León; Mayotte Fil: Idarraga Ospina, Gina. Universidad Autónoma de Nuevo León; Mayotte Fil: Mombello, Enrique Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; Argentina Fil: Cabral, Sergio. Universidade Regional de Blumenau; Brasil

Wavelet Transform (WT) is a powerful technique of signal processing, its applications in power systems have been increasing to evaluate power system conditions, such as faults, switching transients, power quality issues, among others. Electromagnetic transients in power systems are due to changes in the network configuration, producing non-periodic signals, which have to be identified to avoid power outages in normal operation or transient conditions. In this paper a methodology to develop a new adaptive mother wavelet for electromagnetic transient analysis is proposed. Classification is carried out with an innovative technique based on adaptive wavelets, where filter bank coefficients will be adapted until a discriminant criterion is optimized. Then, its corresponding filter coefficients will be used to get the new mother wavelet, named wavelet ET, which allowed to identify and to distinguish the high frequency information produced by different electromagnetic transients.

This paper describes a method based on Lagrange multipliers for efficiently solving the economic dispatch in power systems including point-to-point VSC-HVDC links. The proposed formulation bases on linear models of the AC systems and HVDC links where power losses are properly considered through incremental transmission loss factors. This timely formulation preserves suitable outcome accuracy while showing a greater computational efficiency than what is achieved with classical, nonlinear OPF methods. Its main features are demonstrated using two compelling test cases: a system accommodating one point-to-point VSC-HVDC link and another comprising multi-infeed HVDC connected AC power grids. Results of this approach are compared with those calculated by the nonlinear interior point method. It is confirmed that both fundamentally different approaches are in good agreement since errors smaller than 0.5% were obtained for generation costs, whereas the computational time was reduced by more than 60% with the introduced method. To show the method applicability in realistic power systems, the 10-generator New England Test system incorporating a VSC-HVDC link is studied. The DC link effect on system operation is examined for a 24-hour period dispatch thus demonstrating its usefulness, unrivalled modelling versatility and numerical efficiency with respect to existing approaches.

Resistive Superconducting Fault-Current limiters (r-SFCL) appear as a new attractive technology to address faults in power grids. Based on a new generation of superconductors, referred to as High-Temperature Superconductors (HTS), they could offer economical benefits compared to more conventional technologies. To understand their impact on the electrical networks, two models of r-SFCL, differing by their complexity, were built to conduct short-circuit analysis. Different fault locations in distribution networks were studied in the standard IEEE 13-node and 34-node test feeders. Both models were validated against experimental data and then cross-checked in the IEEE 13-bus distribution system to determine their relative accuracy when used in practical power grids. Subsequently, using the simplest electrical model of r-SFCL, the 34-bus test system incorporating Distributed Generation (DG) was used to analyze short circuits. It was found that the presence of r-SFCL increases the error of the fault location algorithm. However, it was also demonstrated that a single r-SFCL enables the incorporation of several additional DG in a distribution network by reducing the fault current level by at least 45% depending on its design characteristics and the number of added DG. Finally, an improved algorithm is presented. This algorithm takes into account the r-SFCL resistance in order to reduce the fault location error.

The electric arc phenomenon associated with high impedance faults (HIFs) in distribution systems is an exciting subject that directly impacts over the reliability of electrical utilities, because fault currents are very small and present non-linearity and asymmetrical waveforms. Therefore, HIFs may be an undetectable phenomenon by overcurrent protections like fuses, re-closers, and relays. A HIF entails a challenge for its detection and location. In this sense, more realistic high impedance models, as well as reliable signal processing techniques, are needed to extract all transient characteristics aiming to detect HIFs in distribution networks. In this work, an efficient Resistive-HIF model is proposed and implemented into the Alternative Transients Program of the Electromagnetic Transients Program (ATP/EMTP) software to represent the main characteristics of HIFs. The model is compared against well-prove models by using two multiresolution approaches based on the Hermite transform and the Wavelet transform considering different frequency bands.

Objectives To determine the effect of bovine lactoferrin on prevention of late-onset sepsis (LOS) and neurodevelopment delay. Study design Randomized, double-blind, controlled trial in neonates with a birth weight of 500-2000 g in 3 neonatal units in Lima, Peru, comparing bovine lactoferrin 200 mg/kg/day with placebo administered for 8 weeks. The primary outcome was the first episode of culture-proven LOS or sepsis-associated death. Neurodevelopment delay was assessed by the Mullen Scales at 24 months corrected age. Results Of the 414 infants enrolled, 209 received bovine lactoferrin and 205 received placebo. LOS or sepsis-associated death occurred in 22 infants (10.5%) in the bovine lactoferrin group vs 30 (14.6%) in the placebo group; there was no difference after adjusting for hospital and birth weight; hazard ratio 0.73 (95% CI, 0.42-1.26). For infants with birth weights of Conclusions Supplementation with bovine lactoferrin did not decrease the incidence of sepsis in infants with birth weights of Trial registration ClinicalTrials.gov : NCT01525316 .

Power quality (PQ) in microgrids is a relevant topic, particularly with the complex dynamic behaviour of disturbances produced by the electronic components intrinsic in these technologies. In this paper, a qualitative-quantitative hybrid approach named multiscale recurrence quantification decomposition (MSRQD) combined with support vector machines (SVM) is proposed for PQ monitoring in microgrid systems. MSRQD combines variational mode decomposition (VMD) with recurrence quantification analysis (RQA). To validate the effectiveness of the proposed method, it is compared against other methods. In addition, three study cases are conducted in a microgrid test system using simulations, and real measured data of a main distribution feeder to prove the classification capability of the proposed method in a real environment. This novel approach, provides qualitative graphics and quantitative statistical indexes for disturbance localisation, disturbance time evolution and disturbance characterisation, as well as 3D visualisation feature space of perturbations that makes easy the interpretation to the system operator.

For a long time, food microbiota has been studied using traditional microbiological techniques. With the arrival of molecular or culture-independent techniques, a strong understanding of microbiota dynamics has been achieved. However, analyzing the functional role of microbial communities is not an easy task. The application of omics sciences to the study of fermented foods would provide the metabolic and functional understanding of the microbial communities and their impact on the fermented product, including the molecules that define its aroma and flavor, as well as its nutritional properties. Until now, most omics studies have focused on commercial fermented products, such as cheese, wine, bread and beer, but traditional fermented foods have been neglected. Therefore, the information that allows to relate the present microbiota in the food and its properties remains limited. In this review, reports on the applications of omics in the study of traditional fermented foods and beverages are reviewed to propose new ways to analyze the fermentation phenomena.

This paper focuses on the real-time phasor estimation via Taylor-Fourier’s Subspace (TFS) on a low-cost embedded platform. Signal processing is carried out using a sliding window for the sampled signal by the Analog-to-Digital Converter (ADC). A digital Taylor-Fourier filter designed using the TFS, deals with the extraction of the dynamic phasor estimates such as: amplitude, phase angle, frequency, and rate of change of frequency (ROCOF). Then, a Python-based interface is developed to display the real-time monitoring for those parameters. Finally, results exhibit the performance of the implemented phasor estimator attaining reliable estimates for both simulated and real signals, and tracking accurately the changes in amplitude, phase and frequency.

This paper presents the implementation of a simple model of resistive Superconducting Fault Current Limiters (r-ScFCL) based on High Temperature Superconductor (HTS) in the software ATP/EMTP for different transient conditions appearing in distribution networks. The use of fault current limiters (FCL) is rather appealing since they can provide reduction of the short-circuit levels during faults while consuming negligible power in nominal regime. Thus far, a lot of efforts have been dedicated to the design of the equipment and lately only a few works have been focused on the impact of the device in the electrical networks. Topics of interest for the electrical sector cover the study of protection coordination and transient analysis during fault conditions. Both topics ought to be studied from the perspective of power system engineering including new technologies such as ScFCL, for instance. In the present work, part of this effort is carried out. A simplified r-ScFCL model is adopted to evaluate the dynamic performance of a given r-ScFCL under different transient conditions such as faults, transformer energisations and re-closing for distribution systems.

In this study, a novel algorithm for detecting and classifying faults in high-voltage transmission lines is proposed. The algorithm is based on the discrete wavelet transform (DWT) and singular value decomposition (SVD). The DWT is used for extracting the currents’ high-frequency components under fault conditions. Signals under each fault condition are scaled in frequency, in order to build a wavelet matrix. By means of the SVD, the maximum singular value is calculated and employed in this proposal. The attained results exhibit that the maximum singular value represents a good indicator for the issue. This novel approach for detecting and classifying faults in power systems is called maximum wavelet singular value. Phase-to-ground, two-phase to ground, and three-phase faults’ simulations under different fault impedances are carried out by DIgSILENT Power Factory. The analysed fault conditions are evaluated demonstrating that the proposal reduces the computational burden and the time detection.

We aimed to evaluate the impact in sleep quality and musculoskeletal pain of a Medium-Firm Mattress (MFM), and their relationship with objective sleep parameters in a group of institutionalized elders. The sample size included forty older adults with musculoskeletal pain. We did a clinical assessment at baseline and weekly trough the study period of four weeks. We employed the Pittsburgh Sleep Quality Index (PSQI) and Pain Visual Analog Scale (P-VAS). Additionally a sub-group of good sleepers, selected from PSQI baseline evaluation, were studied with actigraphy and randomized to MFM or High Firm Mattress (HFM), in two consecutive nights.We found a significant reduction of cervical, dorsal and lumbar pain. PSQI results did not change. The actigraphy evaluation found a significant shorter sleep onset latency with MFM, and a slightly better, but not statistically significant, sleep efficiency. The medium firmness mattress improved musculoskeletal pain and modified the sleep latency.

This paper discusses the phasor, frequency, and the rate of change of frequency (ROCOF) estimations in Microgrids. This is accomplished using the estimates processed by a real PMU and their comparisons with the digital Cosine filter, adding new metrics for frequency and ROCOF. A real event recorded is employed aiming to estimate the phasor parameters in time-domain signals. A traditional static phasor model algorithm for the digital Cosine filter is taken into account, using a rectangular window lasting two cycles. Both frequency and ROCOF metrics are conceived by drawing an analogy with their estimations if a dynamic phasor model is assumed. The attained results demonstrate that the digital filtering process done by the Cosine filter outperforms the provided estimates by the real PMU and the new metrics suitably track the changes in frequency and ROCOF.

In this paper, a Multi Scale Recurrence Quantification Analysis (MSRQA) method is proposed to clustering harmonics on microgrid systems. MSRQA is composed by the Variational Mode Decomposition algorithm and the Recurrence Quantification Analysis (RQA). MSRQA decomposes a signal into a finite number of Mono-Component Signals (MCSs), then a feature extraction is carry out by the RQA on each MCS. Finally, the identification of the optimal number of clusters based on the features extracted by RQA and the Davies-Bouldin index is carry out on the monitored microgrid system test signals. At the end an index based on the cluster information and the RQA measure is proposed to identify the harmonics present on the dynamic system behavior.

Insulation system conditions in power transformers can be evaluated by means of partial discharge (PD) analyses. In fact, PD analysis is used to detect premature damage in transformer insulation system to avoid catastrophic faults. Detection and location of PD is a complex problem and has been widely studied by several researchers. A new method for PD location in transformer windings based on Wavelet Laplace (WL) is developed in this paper. First, the PD reference signals are obtained from a lumped parameter model (RLC) and those signals are used to determine the WL parameters, then PD signals are analyzed using the WL and each PD reference signal is replaced by its envelope wavelet transform (EWT) coefficients. Then, if a PD signal occurred in any section of the winding, its location will be defined by Hellinger distance between the EWT coefficients and the new PD reference signals. Results are discussed for PD along the winding and between sections of the winding. Fil: Guillen, Daniel. Universidad Autónoma de Nuevo León; México Fil: Idarraga Ospina, Gina. Universidad Autónoma de Nuevo León; México Fil: Mombello, Enrique Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Energía Eléctrica. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Energía Eléctrica; Argentina

α-Glucans are present in virtually all domains of life, and these glucose chains linked by α-1,4- and α-1,6-linked branches form the most important storage carbohydrates in cells. It is likely for this reason that α-glucans are not generally considered as bioactive molecules as β-glucans are. Nevertheless, it is known that depending on their source, many α-glucans play important roles as modulators of immune response. Recent efforts have attempted to elucidate the mechanisms through which α-glucans exert their immunostimulant effects; however, the main challenge is the accurate identification of the receptors of immune cells involved in their recognition. Here, we review the adjuvant properties reported for some polysaccharides and ultimately focus on α-glucans and how their structural characteristics, such as molecular weight, solubility and derivatization, influence their immunostimulatory properties. As a final point, we discuss the potential and associated challenges of using these polysaccharides as adjuvants, particularly in mucosal vaccination.

Interturn faults are a critical problem in power transformers that can eventually escalate into catastrophic faults and probably result in an overall network failure. Also, failures in transformer windings are still a major cause of transformer outages, and failure rates vary widely between different countries and systems, depending on many factors. Therefore, in this work, interturn faults with various levels of severity were imposed on the winding of a 120 VA, 24/125 V dry type transformer to diagnose it. The obtained signals during the experiments are processed using the Wavelet Transform and correlation modes. This technique only takes into account the high frequency information produced during the energization of a winding with interturn faults.

El objetivo del estudio fue describir las características de consulta neurológica y referencia de los niños con parálisis cerebral (PC). Estudio descriptivo retrospectivo. Se evaluaron las historias clínicas de los niños con PC asistentes a consulta externa de la unidad de Neuropediatría del Hospital Nacional Cayetano Heredia entre los años 2011 y 2012. Se incluyeron 81 niños, el 53,1% fueron varones; la PC espástica fue la más frecuente (72,8%), la encefalopatía hipóxico isquémica (28,1%) y las malformaciones cerebrales (28,1%) fueron las principales causas en neonatos a término. La edad media al momento del diagnóstico fue a los 4,1 ± 3,2 años, la epilepsia fue el motivo más frecuente de consulta neuropediátrica. El 58% fue hospitalizado al menos una vez. El tiempo de espera para ser atendido por terapia física tuvo una mediana de 2 meses (rango intercuartílico = 0,8 - 9). Concluimos que el diagnóstico de PC fue tardío, el tiempo de espera para acceder a la atención especializada fue prolongado. Se requieren protocolos y mayor eficiencia para atender en forma adecuada a los niños con PC. The aim of this study was to describe the neurological consultation and baseline characteristics of children with cerebral palsy (CP). The clinical records of children with CP attending an external consultation of the Neuropediatric department of Hospital Nacional Cayetano Heredia between 2011 and 2012 were assessed in this retrospective descriptive study. A total of 81 children were included: 53.1% were boys. Spastic CP was the most frequent (72.8%), hypoxic-isquemic encephalopathy (28.1%) and cerebral malformations (28.1%) were the main causes in term newborn. The average age at the time of diagnosis was 4.1 ± 3.2 years; epilepsy was the most frequent reason for neuropediatric consultation, and 58% were admitted to the hospital at least once. The waiting period to be seen by a physical therapist was around 2 months (interquartile range = 0.8-9). We reached the conclusion that CP was delayed, and the waiting period to access specialized care was prolonged. Protocols and increased efficiency are required to provide adequate medical care to children with CP.

La Epilepsia es una enfermedad crónica que en muchos casos se encuentra ligada a conceptos mágico-religiosos que condicionan rechazo social. Objetivo: Elaborar y validar un cuestionario que permita medir el grado de conocimientos y creencias sobre epilepsia en los padres de familia. Material y métodos: Se realizó un estudio transversal para la construcción de un instrumento válido y confiable. Se determinó la validez cualitativa por medio del análisis de expertos y la validez cuantitativa, (confiabilidad y validez interna), a través del cálculo del KR-20, el índice de correlación intraclase y el índice de discriminación, respectivamente. Resultados: El coeficiente KR- 20 fue de 0,89 y el coeficiente de correlación intraclase 0,986, ambos considerados como valores altos. Además, se obtuvo valores para el índice de discriminación de cada ítem dentro de los límites aceptados. Conclusiones: El instrumento elaborado es válido y confiable. Epilepsy is a chronic disease that is mostly associated with magic-religious concepts that generate social rejection. Objective: To develop and validate a questionnaire that allows measurement of the degree of knowledge and beliefs on epilepsy in parents. Methods: A cross-sectional study was conducted to develop and validate a valid and reliable instrument. Qualitative validity of the instrument was performed by analysis of experts, and quantitative validity (reliability and internal validity) was evaluated by calculating KR-20, index of intra-class correlation and discriminative index. Results: KR-20 coefficient was 0.89 and the intra-class correlation coefficient was 0.986, both were considered high values. In addition, the discriminative index value for each item was within accepted limits. Conclusions: The instrument developed is valid and reliable.

We report a case of non-immune hydrops and intrauterine cytomegalovirus infection is reported. Dropsy was diagnosed by ultrasound at 31 weeks of gestational age. Ultrasonographic features of the intrauterine fetal hydrops and newborn described. Other evaluations and studies to determine associated malformations was performed, which is discarded confirmed the suspected diagnosis of cytomegalovirus infection and fetal hydrops. Se reporta un caso de hidropesía fetal no inmunológica e infección intrauterina por citomegalovirus. La hidropesía fue diagnosticada por ultrasonografía a las 31 semanas de edad gestacional. Se describe las características ecográficas de la hidropesía fetal intraútero y del recién nacido. Se realizó otras evaluaciones y estudios para determinar malformaciones asociadas, las que al se descartadas confirmaron la sospecha diagnóstica de infección por citomegalovirus e hidropesía fetal.

Treatment issues of multiple sclerosis (MS) in Latin America (LA) have recently been addressed. Some particular features of the health systems, patients and medical providers are scarcely described. Moreover, LA patients are rarely included in clinical trials; therefore, data collected from key opinion leaders (KOL) from LA, although unofficial, remain as a needed source of information. In a stand-alone gathering, organized by a pharmaceutical company, in Brazil 2014, according to ‘Compliance Program Guidance for Pharmaceutical Manufacturers', we surveyed the opinion of KOL in MS from 6 LA countries. Neurologists were selected and invited to the gathering based on their academic, research and clinical experience with MS patients and involvement as participants and speakers on regional events. A voluntary anonymous electronic survey was proposed in an interactive lecture (table 1). Important definitions were given previously without further discussion on the topic to avoid biased answers.

Microparticles of diverse compositions are often used as carriers for interesting antigens. In this work, we propose the use of natural microparticulated starch as a vehicle for antigens. The proposed system is composed of raw starch microparticles and a starch-binding domain that when fused to another protein, allows for a stable protein immobilization onto the granule surface. To demonstrate the use of starch as an antigen carrier, a fusion combining fragment C of the tetanus toxin with the starch-binding domain was adsorbed to starch and administered orally to mice in two different doses and, importantly, without the use of any adjuvant. The results showed that the system allows the induction of specific antibodies; moreover mice given this immobilized protein presented a delay in the onset of tetanus symptoms compared to mice administered the non-immobilized protein. The study outlines the viability of this immobilization system as an antigen and protein carrier.

Microparticles have been used as promising carriers for in vivo vaccine delivery. However, the processes for immobilizing peptides or proteins on microparticles usually require the use of undesirable compounds and complex protocols. In this work, we propose a new immobilization and delivery system with raw starch microparticles and a starch binding domain (SBD) tag fusion protein. The heat shock protein alpha crystallin from Mycobacterium tuberculosis was used as model. The immunogenicity of the system was investigated in BALB/c mice inoculated with purified Acr-SBDtag protein (pAcr-SBDtag) and starch immobilized Acr-SBDtag protein (μAcr-SBDtag) by oral and intranasal routes. We demonstrated mucosal immunization with the μAcr-SBDtag protein induced systemic antibodies that were predominantly immunoglobulin G2a (IgG2a). An analysis of the cytokines from spleen cells and lung homogenates revealed that loaded microparticles induced the secretion of interferon-γ (INF-γ), suggesting an adjuvant effect from the immobilization. The immune responses induced by immobilized protein were primarily affected by the route of administration. These results demonstrate that the system exhibits the necessary characteristics to improve antigen release and presentation to antigen presenting cells (APCs) in the mucosae. Because no extra adjuvants were used, we posit that the system may be suitable for delivery and presentation to the field of subunit vaccine development.

Se presenta el caso de una niña de 12 años de edad con siete meses de evolución de signos focales e hipertensión endocraneana progressiva. Con ayuda de la TAC se diagnosticó tumoración quística gigante compatible a hidatidosis cerebral. Se realizó craneotomía y extirpación del quiste sin complicaciones. La hidatidosis cerebral es rara, su diagnóstico es clínico-tomográfico y el tratamiento siempre es quirúrgico. Case report of a 12 years old female child who developed in the last seven months focal neurological signs and progressive intracranial hypertension. CT scan showed a giant cystic tumor, and cerebral hydatidosis has been diagnosed. The hydatic cyst was surgically removed without complications. Cerebral hydatidosis is rare, its diagnosis is clinical and tomographic, and the treatment is always surgical.

Se presentan setenta niños diagnósticados de MEC TBC entre enero de 1982 y diciembre de 1991. El análisis demostró una ocurrencia de 9.4 casos por año, siendo los escolares el grupo etáreo más afectado así como el contacto tuberculoso, el hacinamiento y la desnutrición los antecedentes más importantes. El tiempo con compromiso de conciencia transcurrido previo a la hospitalización fue el factor que determinó el estadío clínico de ingreso y la condición de alta. La letalidad encontrada fue de 14.3%.

We present the case of a three year old girl who showed two adverse reactions to DPH, one of them a large cervical lymphatic hyperplasia, which responded to discontinuation of the drug. Laboratory test were normal and histological examination showed non specific adenitis. We discuss this unusual case and the importance of the cervical adenopathy differential diagnosis.

Objetivo: Conocer la prevalencia de migraña en los estudiantes de Medicina de una universidad en Lima- Perú, y determinar la relación de acuerdo al año de estudios, edad, sexo, antecedente familiar de migraña, rinitis alérgica, consumo de tabaco y su presentación clínica. Materiales y métodos: Se realizó un estudio transversal, encuestándose al total de la población de estudiantes de Medicina de una Universidad en Lima - Perú empleando el auto-cuestionario validado ‘Alcoi-95’. Resultados: Se incluyeron 697 estudiantes de los cuales el 52,2% fueron mujeres. La edad promedio de la población fue de 21,5 años. La prevalencia de migraña fue de 31,1%, siendo mayor en los alumnos de primer año (45,6%) y en el grupo etario de 15 a 20 años (40,4%). Los casos de migraña se encontraron significativamente asociados con el antecedente familiar de migraña y el sexo masculino. Conclusiones: La migraña es una enfermedad prevalente en los estudiantes de Medicina de esta universidad, especialmente en los primeros años de estudios. Se encontró una asociación con el género masculino y el antecedente familiar de migraña.

Insoluble polysaccharides can be degraded by a set of hydrolytic enzymes formed by catalytic modules appended to one or more non-catalytic carbohydrate-binding modules (CBM). The most recognized function of these auxiliary domains is to bind polysaccharides, bringing the biocatalyst into close and prolonged vicinity with its substrate, allowing carbohydrate hydrolysis. Examples of insoluble polysaccharides recognized by these enzymes include cellulose, chitin, beta-glucans, starch, glycogen, inulin, pullulan, and xylan. Based on their amino acid similarity, CBMs are grouped into 55 families that show notable variation in substrate specificity; as a result, their biological functions are miscellaneous. Carbohydrate or polysaccharide recognition by CBMs is an important event for processes related to metabolism, pathogen defense, polysaccharide biosynthesis, virulence, plant development, etc. Understanding of the CBMs properties and mechanisms in ligand binding is of vital significance for the development of new carbohydrate-recognition technologies and provide the basis for fine manipulation of the carbohydrate-CBM interactions.