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A 14-year-old boy with a history of atrial tachycardia presented to the emergency department with acute right foot weakness. One month prior to presentation, he had a self-resolving diarrheal illness and bacterial pneumonia treated with antibiotics. Two weeks later, he endorsed a dull headache, increased irritability, and neck pain. One week prior to presentation, he developed intermittent urinary retention and episodes of flushing and redness of his right face. He fell 5 days prior to presentation and in the ensuing days, he complained of bilateral hip pain and paresthesias that progressively spread to involve bilateral thighs. On the day of presentation, the patient noticed weakness of his right ankle and foot. There was no history of fever. He denied joint pain, swelling, rash, or facial droop, but he did endorse mild sound sensitivity.

Fault detection and location is a challenging issue in microgrid protection, which is increasingly more complex in the presence of distributed generators based on renewable energy, due to their inherent intermittency. In this context, a novel data-driven approach for fault detection and location in microgrids is proposed, by using graph theory representation and micro-synchrophasors also known as μ PMUs. This proposal adopts the conviction to provide an accurate fault location even under variations in short-circuit levels caused by the intermittency of distributed generators. This is in sharp contrast with traditional short-circuit rating-based methods, which are not always advisable due to the intermittent nature of power sources. This work proposes the use of a modelling specification in terms of equilibrium equations, that can reveal not only the underlying physical laws of the netowork, but also the occurrence and location of short circuits based on phasor data. The intermittency of distributed generation is modelled in the proposed approach, which permits to yield trustworthy information either distributed generators are involved in a fault or not. As a consequence, the fault location errors are significantly reduced during the fault location process. The theoretical findings of this proposal are validated via simulation results and experiments using commercial micro-synchrophasors and hardware-in-the-loop emulation of a realistic microgrid.

Objectives The aim of this study was to investigate the feasibility of saliva sampling as a non-invasive and safer tool to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and to compare its reproducibility and sensitivity with nasopharyngeal swab samples (NPS). The use of sample pools was also investigated. Methods A total of 2107 paired samples were collected from asymptomatic healthcare and office workers in Mexico City. Sixty of these samples were also analyzed in two other independent laboratories for concordance analysis. Sample processing and analysis of virus genetic material were performed according to standard protocols described elsewhere. A pooling analysis was performed by analyzing the saliva pool and the individual pool components. Results The concordance between NPS and saliva results was 95.2% (kappa 0.727, p = 0.0001) and 97.9% without considering inconclusive results (kappa 0.852, p = 0.0001). Saliva had a lower number of inconclusive results than NPS (0.9% vs 1.9%). Furthermore, saliva showed a significantly higher concentration of both total RNA and viral copies than NPS. Comparison of our results with those of the other two laboratories showed 100% and 97% concordance. Saliva samples are stable without the use of any preservative, and a positive SARS-CoV-2 sample can be detected 5, 10, and 15 days after collection when the sample is stored at 4 °C. Conclusions The study results indicate that saliva is as effective as NPS for the identification of SARS-CoV-2-infected asymptomatic patients. Sample pooling facilitates the analysis of a larger number of samples, with the benefit of cost reduction.

Introduction Polymerase chain reaction (PCR) testing of cerebrospinal fluid (CSF) is a sensitive and specific method in diagnosing herpes simplex virus (HSV) encephalitis. However there are increasing reports of false negative HSV PCR. Case description We present a patient in the 9th decade of life with abnormal behavior and focal seizures with MRI showing a right temporal T2 hyperintense non-enhancing lesion with electrographic evidence of right lateralized periodic discharges. CSF analysis and PCR for HSV-1 and 2 yielded negative results twice, and therefore acyclovir was discontinued. Patient initially improved following correction of hyponatremia. Patient however deteriorated and imaging revealed a new right parietal lesion. Third CSF sample showed lymphocytic pleocytosis with positive HSV-1 PCR. Patient improved following antiviral treatment. Discussion Acyclovir treatment should continue in high clinical suspicion scenarios despite negative HSV PCR. We further discuss causes of PCR false negatives and challenges it poses for patient care., Neuroscience; Nervous System; Viral Disease; Neurology; Diagnostics; neurovirology, MRI, infectious disease, EEG

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.

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 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.

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.

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.

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 .

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.

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.

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

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.

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.

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.

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.

We studied clinical and EEG features of 36 cases with congenital malformations of the CNS. Patients were followed at the outpatient clinic of Hospital Cayetano Heredia and of Hogar Clinica San Juan de Dios in Lima-Peru, from January 1984 to June 1992. Eighty percent of the patients had convulsive syndromes and mental retardation. The most frequent malformation was agenesis of corpus callosum, and it was not possible to find a "typical" EEG pattern. The second were porencephalic cysts, with a good clinical-EEG correlation. There were two typical cases of schizencephaly, one of hemimegalencephaly with good prognosis, and one of holoprosencephaly. The results are compared to those obtained for a series we previously reported. Data discussed take into account reports on the subject registered in the literature. It is concluded that EEG is an useful method to evaluate possible CNS malformations in developing countries. Estudiamos aspectos clínicos e del EEG de 36 casos de malformaciones congénitas del sistema nervioso central. Los pacientes fueron seguidos en los consultorios externos del Hospital Cayetano Heredia y del Hogar Clínica San Juan de Dios en Lima-Peru, desde enero 1984 hasta junio 1992. Ochenta por ciento de los pacientes presentaron sindrome convulsivo y retardo mental. La anormalidad mas frecuente correspondió a agenesia de cuerpo calloso y no fue posible identificar un patron EEG "típico". El segundo lugar correspondió a quistes porencefálicos, con buena correlación clínico-EEG. Ademas, hubieron dos casos clínicamente típicos de esquizencefalia, una hemimegalencefalia con buen prognóstico y un caso de holoprosencefalia. Se comparan los resultados con aquellos de casos previamente revisados. Se discuten los dados frente a la literatura acerca de los patrones EEG mas frecuentemente relatados. Se concluye en la utilidad del EEG en países en desarrollo para hacer posible un alto grado de sospecha de una malformación del SNC aun en ausencia de CAT-scan.