Confirmación del método de ayuda diagnóstica de la dinámica cardiaca de aplicación clínica desarrollado con base en la teoría de la probabilidad

A partir de la teoría de probabilidad y los sistemas dinámicos se desarrolló previamente una nueva metodología de ayuda diagnóstica para el Holter con base en la teoría de la probabilidad. El propósito de este trabajo es evaluar su concordancia diagnóstica en casos normales y con enfermedad aguda. Se tomaron 15 Holters normales y 100 con diferentes patologías cardiacas de pacientes mayores a 20 años. Se establecieron rangos de frecuencias cardiacas y de número de latidos por hora y se calculó la probabilidad de estos rangos. Los valores obtenidos se analizaron de acuerdo con los parámetros diagnósticos establecidos en la metodología previamente desarrollada para diferenciar normalidad de enfermedad. Finalmente se evaluó sensibilidad, especificidad y coeficiente Kappa de la evaluación física matemática respecto al diagnóstico convencional para los casos normales y con enfermedad aguda.Los Holter con enfermedad aguda presentaron entre 6 y 13 rangos de frecuencias y los normales entre 13 y 21 rangos. La probabilidad máxima de latidos por hora en normalidad presentó cuatro casos con probabilidad menor o igual a 0,217 o mayor o igual a 0,304, mientras que para enfermedad aguda todos tuvieron valores mayores o iguales a 0,304. De los Holter, 5 con enfermedad aguda, y 2 normales presentaron un número de latidos menor a 3.000. La suma de las probabilidades de las dos frecuencias más probables se encontró entre 0,203 y 0,379 para los normales y entre 0,333 y 0,652 para los Holters con patologías agudas. Los valores de sensibilidad y especificidad fueron de 100% Y 73,3% y el coeficiente Kappa de 0,86. Se confirmó que la metodología desarrollada con base en la teoría de la probabilidad revela una autoorganización del sistema cardiaco que permite diferenciar normalidad de enfermedad aguda y evidenciar la evolución entre ambos a nivel clínico

3D Visualization of the Iron Oxidation State in FeO/Fe3O4 Core-Shell Nanocubes from Electron Energy Loss Tomography

The physicochemical properties used in numerous advanced nanostructured devices are directly controlled by the oxidation states of their constituents. In this work we combine electron energy-loss spectroscopy, blind source separation, and computed tomography to reconstruct in three dimensions the distribution of Fe and Fe ions in a FeO/FeO core/shell cube-shaped nanoparticle with nanometric resolution. The results highlight the sharpness of the interface between both oxides and provide an average shell thickness, core volume, and average cube edge length measurements in agreement with the magnetic characterization of the sample

Mis casos clínicos de especialidades odontológicas

Libro que muestra la atención de casos clínicos particulares referente a las diferentes especialidades odontológicasLibro que muestra la atención de casos clínicos particulares referente a las diferentes especialidades odontológicasUniversidad Autónoma de Campeche Universidad Autónoma del Estado de Hidalgo Universidad Autónoma del Estado de Méxic

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

Water Dynamics in Hydrated Carboxylated Cellulose Nanofibril Membranes

Cellulose nanofibrils (CNF) are a class of materials with good mechanical properties, surface functionality and bio-/environmental friendliness. They have been used in many applications as loading material or function materials, where water-cellulose interaction determines the materials performance. Especially, CNF with carboxylated groups can be used as the separation membrane in polymer electrolyte membrane fuel cell. The water dynamics is closely related to the proton conductivity. The Non-destructive quasi-elastic neutron scattering (QENS) is used to characterized water movement in hydrated membrane made of CNF prepared by TEMPO-oxidation with different surface charges. However, neither surface charge nor the nanoconfinement due to membrane swelling has large impact on water dynamics mechanism. A slow diffusive motion is found with the diffusion coefficient close to bulk water and that in hydrated Nafion membrane regardless the surface charge, while a fast motion is rather localized with a correlation time increasing as temperature increase, which might related to the hydrogen bond network formation between water and CNF

Tuning the Magnetic Alignment of Cellulose Nanocrystals from Perpendicular to Parallel Using Lepidocrocite Nanoparticles

The magnetic alignment of cellulose nanocrystals (CNC) and lepidocrocite nanorods (LpN), pristine and in hybrid suspensions has been investigated using contrast-matched small-angle neutron scattering (SANS) under in situ magnetic fields (0 – 6.8 T) and polarized optical microscopy. The pristine CNC (diamagnetic) and pristine LpN (paramagnetic) align perpendicular and parallel to the direction of field, respectively. The alignment of both the nanoparticles in their hybrid suspensions depends on the relative amount of the two components (CNC and LpN) and strength of the applied magnetic field. In the presence of 10 wt% LpN and fields < 1.0 T, the CNC align parallel to the field. In the hybrid containing lower amount of LpN (1 wt%), the ordering of CNC is partially frustrated in all range of magnetic field. At the same time, the LpN shows both perpendicular and parallel orientation, in the presence of CNC. This study highlights that the natural perpendicular ordering of CNC can be switched to parallel by weak magnetic fields and the incorporation of paramagnetic nanoparticle as LpN, as well it gives a method to influence the orientation of LpN.<br /

Highly proton conductive membranes based on carboxylated cellulose nanofibres and their performance in proton exchange membrane fuel cells

The performance of thin carboxylated cellulose nanofiber-based (CNF) membranes as proton exchange membranes in fuel cells has been measured in-situ as a function of CNF surface charge density (600 and 1550 µmol g-1), counterion (H+or Na+), membrane thickness and fuel cell relative humidity (RH 55 to 95 %). The structural evolution of the membranes as a function of RH, as measured by Small Angle X-ray scattering, shows that water channels are formed only above 75 % RH. The amount of absorbed water was shown to depend on the membrane surface charge and counter ions (Na+or H+). The high affinity of CNF for water and the high aspect ratio of the nanofibers, together with a well-defined and homogenous membrane structure, ensures a proton conductivity exceeding 1 mS cm-1at 30 °C between 65 and 95 % RH. This is two orders of magnitude larger than previously reported values for cellulose materials and only one order of magnitude lower than Nafion 212. Moreover, the CNF membranes are characterized by a lower hydrogen crossover than Nafion, despite being ≈ 30 % thinner. Thanks to their environmental compatibility and promising fuel cell performance the CNF membranes should be considered for new generation proton exchange membrane fuel cells.</p

Neither Sphere nor Cube - Analyzing the Particle Shape Using Small-Angle Scattering and the Superball Model

Accurate characterization of the nanocrystal shape with high statistical relevance is essential for exploiting the strongly shape-dependent properties of cuboidal nanoparticles towards applications. This work presents the development of a new small-angle scattering form factor based on the superball geometry. The superball quantifies the characteristic rounding of corners and edges of cuboidalnanoparticles with a single parameter. Applied to small-angle scattering data of sufficiently monodisperse nanoparticles, the superball form factor enables differentiation between the effects of extendedparticle size distribution and irregular particle shape. The quantitative application of the superball form factor is validated against microscopy data for a series of monodisperse nanoparticles and implemented into the user-friendly, open source software Sasview

Inducing Nematic Ordering of Cellulose Nanofibers using Osmotic Dehydration

The formation and characterization of nematically-ordered CNF materials (maximum order parameter f ≈ 0.8) has been studied by polarized optical microscopy, small angle x-ray scattering (SAXS), and rheological measurements as a function of CNF concentration. The wide range of CNF concentrations, from 0.5 wt% to 4.9 wt%, is obtained using osmotic dehydration with PEG. At concentrations >1.05 wt% the CNF suspension crosses an isotropic-anisotropic transition that is accompanied by a dramatic increase of the optical birefringence. The resulting nanostructures are depicted by a hierarchical model with mass fractal structures that converge into co-existing nematically-ordered regions and network-like regions, in which the correlation distances decrease upon increasing concentration. The use of rapid, upscaleble osmotic dehydration is an effective method to increase the concentration of CNF suspensions while partly circumventing the gel formation. The facile formation of highly ordered fibers can result in materials with interesting macroscopic properties.</div