Search results for "WB"
showing 10 items of 1688 documents
Localización de interiores mediante radiofrecuencia: Estudio, análisis y propuestas de mejora
2019
El sistema de posicionamiento global (GPS) es el sistema más utilizado en aplicaciones de localización en exteriores, pero es ineficiente para la localización en interiores. En los últimos años, los sistemas de posicionamiento en interiores se han desarrollado ampliamente. Para ello se han utilizado varias tecnologías inalámbricas, como ZigBee, WLAN y banda ultra ancha (UWB). Los principales métodos de medición de la señal inalámbrica en los sistemas de localización en interiores son el tiempo de llegada (TOA), la diferencia de tiempo de llegada (TDOA), el ángulo de llegada (AOA) y la indicación de intensidad de señal recibida (RSSI). Los sistemas de posicionamiento TOA, TDOA y AOA requiere…
Epidemiology of congenital diaphragmatic hernia in Europe: a register-based study.
2015
INTRODUCTION: Published prevalence rates of congenital diaphragmatic hernia (CDH) vary. This study aims to describe the epidemiology of CDH using data from high-quality, population-based registers belonging to the European Surveillance of Congenital Anomalies (EUROCAT).METHODS: Cases of CDH delivered between 1980 and 2009 notified to 31 EUROCAT registers formed the population-based case series. Prevalence over time was estimated using multilevel Poisson regression, and heterogeneity between registers was evaluated from the random component of the intercept.RESULTS: There were 3373 CDH cases reported among 12 155 491 registered births. Of 3131 singleton cases, 353 (10.4%) were associated wit…
Anorectal malformations and pregnancy-related disorders: a registry-based case-control study in 17 European regions
2013
Objective To identify pregnancy-related risk factors for different manifestations of congenital anorectal malformations (ARMs).Design A population-based case-control study.Setting Seventeen EUROCAT (European Surveillance of Congenital Anomalies) registries, 1980-2008.Population The study population consisted of 1417 cases with ARM, including 648 cases of isolated ARM, 601 cases of ARM with additional congenital anomalies, and 168 cases of ARM-VACTERL (vertebral, anal, cardiac, tracheo-esophageal, renal, and limb defects), along with 13371 controls with recognised syndromes or chromosomal abnormalities.Methods Multiple logistic regression analyses were used to calculate adjusted odds ratios …
Effectiveness of microwave based digestion procedures for the demineralization of human milk and infant formulas prior to fluorometric determination …
1996
The use of two types of microwave oven, one domestic (A) and the other specially designed for laboratory (B) for microwave-based digestion, to destroy the organic matter in milk and infant formulas prior to fluorometric determination of selenium is studied in order to check their applicability and reliability. In both systems the best results were obtained using the acid mixture HNO3—H2O2, and additional treatment with perchloric acid (60%) in a Thermoblock. The application of two different microwave-based digestion procedures to infant formulas was free of interferences. In the case of human milk, it was necessary to use the standard addition method. Values obtained for detection and quant…
Isocratic high-performance liquid chromatographic determination of tryptophan in infant formulas.
1996
The application to infant formulas of a method for tryptophan determination by isocratic HPLC with UV detection at 254 nm, after derivatization with phenyl isothiocyanate, was studied. Protein was hydrolysed by barium hydroxide at 120 degrees C for 8 h, followed by derivatization with phenyl isothiocyanate, HPLC and UV detection at 254 nm. The optimum chromatographic conditions (pH, ionic strength of elution solvent and eluent ratio) were established. The analytical parameters (linearity, precision, accuracy of derivatization and limits of detection and quantification) were determined. The values obtained demonstrated that the method is useful for determining the tryptophan content of infan…
Rapid developmental switch in the mechanisms driving early cortical columnar networks
2006
The immature cerebral cortex self-organizes into local neuronal clusters long before it is activated by patterned sensory inputs. In the cortical anlage of newborn mammals, neurons coassemble through electrical or chemical synapses either spontaneously or by activation of transmitter-gated receptors. The neuronal network and the cellular mechanisms underlying this cortical self-organization process during early development are not completely understood. Here we show in an intact in vitro preparation of the immature mouse cerebral cortex that neurons are functionally coupled in local clusters by means of propagating network oscillations in the beta frequency range. In the newborn mouse, this…
Physiological and metabolic actions of mycophenolate mofetil on cultured newborn rat cardiomyocytes in normoxia and in simulated ischemia
2004
Mycophenolate mofetil (MMF) is a new immunosuppressive drug used to reduce acute rejection after heart transplantation. As with other immunosuppressive drugs, MMF therapy is associated with several adverse effects. However, the direct effects of MMF on myocardial tissue has not been yet evaluated. The aim of the work was thus to evaluate the effects of MMF on isolated cardiomyocytes (CM) in normal conditions and in an in vitro model of simulated ischemia (SI; substrate-free hypoxia) and reperfusion (R; reoxygenation). Myocyte-enriched cultures were prepared from newborn rat heart ventricles. The transmembrane potentials were recorded using conventional microelectrodes and the cell contracti…
Orbital volume and shape in Treacher Collins syndrome
2018
Orbito-palpebral reconstruction is a challenge in Treacher Collins syndrome (TCS). This study investigates orbital phenotypes in TCS using cephalometry and orbital shape analysis. Eighteen TCS and 52 control patients were included in this study, using the Dr Warehouse database. Orbital cephalometry was based on 20 landmarks, 10 planes, 16 angles, and 22 distances. Orbits were segmented. Registration-based, age-specific mean models were generated using semi-automatic segmentation, and aligned and compared using color-coded distance maps - mean absolute distance (MAD), Hausdorff distance (HD), and Dice similarity coefficient (DSC). Symmetry was assessed by mirroring and DSC computing. Central…
Sonographic biometry of liver and spleen size in childhood.
1983
In 194 healthy children of all ages, sonographic measurements of the liver and spleen were performed on standardized section planes and normal values established. These measurement values showed an approximately linear increase in the course of development and correlated best with the body length. For a rapid orientational evaluation of the liver size, sonographic nomograms of the individual measurements were developed. The spleen size was determined by volume calculation. On the basis of an index of liver size, which was calculated from the individual measurements, a diagram for simultaneous determination of liver and spleen size could be developed. These nomograms permit objective morphom…
Evaluation of the pulse wave arrival time as a marker for blood pressure changes in critically ill infants and children
1995
Objective. Pulse arrival time (PAT), which is the interval between the R wave of the electrocardiogram (ECG) and the arrival of the pulse wave peripherally, has been reported to be suitable for use as an indirect measure of blood pressure change. The purpose of this study was to evaluate, in critically ill infants and children, the degree to which 1/PAT covaries with systolic, diastolic, and mean blood pressure, as well as heart rate.Methods. A laboratory device was used to calculate PAT in real time from the ECG and the plethysmographic curve of pulse oximetry used for routine monitoring. Calculated PAT and corresponding blood pressures and heart rate were stored on hard disk. A total of 1…