Search results for "SELE"
showing 10 items of 4721 documents
Clickstream Data Analysis: A Clustering Approach Based on Mixture Hidden Markov Models
2023
Nowadays, the availability of devices such as laptops and cell phones enables one to browse the web at any time and place. As a consequence, a company needs to have a website so as to maintain or increase customer loyalty and reach potential new customers. Besides, acting as a virtual point-of-sale, the company portal allows it to obtain insights on potential customers through clickstream data, web generated data that track users accesses and activities in websites. However, these data are not easy to handle as they are complex, unstructured and limited by lack of clear information about user intentions and goals. Clickstream data analysis is a suitable tool for managing the complexity of t…
Phase-selective low molecular weight organogelators derived from allylated D-mannose
2022
In the last decades, synthesis and design of low molecular weight organogelators has gained increasing attention due to their versatile use in, for example, cosmetics, biomedicine and oil spill remediation. In this work, three potential gelators have been prepared from allylated d-mannose. Both the gelators and the corresponding gels formed were thoroughly characterized by crystallography, FTIR spectroscopy, SEM, rheometry and NMR spectroscopy, in solution and in solid state. The results showed that two of the compounds phase-selectively form gels with hydrocarbon solvents. The most promising gelator compound is alkene terminated, with the unsaturated end functionality not critical for gel …
Prediction of harmful variants on mitochondrial genes : Test of habitat-dependent and demographic effects in a euryhaline fish
2017
Both effective population size and life history may influence the efficacy of purifying selection, but it remains unclear if the environment affects the accumulation of weakly deleterious nonsynonymous polymorphisms. We hypothesize that the reduced energetic cost of osmoregulation in brackish water habitat may cause relaxation of selective constraints at mitochondrial oxidative phosphorylation (OXPHOS) genes. To test this hypothesis, we analyzed 57 complete mitochondrial genomes of Pungitius pungitius collected from brackish and freshwater habitats. Based on inter- and intraspecific comparisons, we estimated that 84% and 68% of the nonsynonymous polymorphisms in the freshwater and brackish …
Factor selection procedures in a Google Earthtm aided landslide susceptibility model: application to the Beiro river basin (Spain)
2011
A procedure to select the controlling factors connected to the slope instability has been defined. It allowed to assess the landslide susceptibility in the Rio Beiro basin (about 10 km2) over the north-eastern area of the city of Granada (Spain). Field and remote (Google EarthTM) recognition techniques allowed to generate a landslide inventory consisting in 127 phenomena. Univariate tests, using both association coefficients and validation results of single parameter susceptibility models, allowed to select among 15 controlling factors the ones that resulted as good predictor variables; these have been combined for unique conditions analysis and susceptibility maps were finally prepared. In…
Differences in estimates of change of bone accrual and body composition in children because of scan mode selection with the prodigy densitometer.
2004
Abstract Girls of age 10–13 yr with Tanner stage I–III maturation status ( n = 155) were measured using the Prodigy (GE Lunar) densitometer. Bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were assessed for the whole body, lumbar spine, and proximal femur using the Thin (T) and Standard (S) scan modes at years 1 and 3 of the study. The differences obtained between the T and S mode at year 1 were 1–2% for the lumbar spine and proximal femur and 5–11% for the whole body. For those girls whose default mode changed from T at year 1 to S mode at year 3, the estimated gain in BA, BMC, and BMD was 3.4%, 7.6%, and 3.1% respectively, lower than that obtained when scanning …
Revista electrónica de investigación y evaluación educativa
2014
Resumen tomado de la publicación Título, resumen y palabras clave en inglés y español La igualación equipercentil es un método estadístico en el cual los puntajes crudos de dos versiones de una prueba se consideran igualados si ellos corresponden al mismo rango percentilar en un grupo de examinados. En la igualación equipercentil se presenta una curva para describir las diferencias de dificultad de versión a versión. Se tiene como objetivo estimar la igualación equipercentil sin suavizado de las versiones 3 y 4, con la versión 2, por área temática del Examen de Habilidades y Conocimientos Básicos (EXHCOBA) que utiliza la Universidad Autónoma de Baja California (UABC) para la selección de as…
Raw data for the publication "Effect of graphene substrate type on formation of Bi2Se3 nanoplates", Sci. Rep. 9, 4791, 2019. https://doi.org/10.1038/…
2020
This dataset contains the raw AFM and SEM measurement data used for the study of stages of formation of Bi2Se3 nanoplates on different substrates and for the statistical analysis of sizes and thicknesses of the nanoplates. The results are published in Sci. Rep. 9, 4791, 2019. https://doi.org/10.1038/s41598-019-41178-1
Characterisation of single semiconductor nanowires by non-destructive spectroscopies
2015
Los nanohilos semiconductores (NWs, de su nombre inglés, nanowires) tienen una amplia gama de aplicaciones en el campo de la optoelectrónica (emisores de luz y diodos láser), nano-electrónica (circuitos lógicos y transistores de efecto de campo), y detección y producción de energía (células solares). En términos generales, los NWs pueden ser descritos como nanoestructuras de forma alargada con diámetros que van típicamente de decenas a cientos de nanómetros, y con longitudes que oscilan desde pocas hasta las decenas de micras. Dicha morfología ofrece dos ventajas principales en comparación con las capas: su alta relación superficie-volumen y su mayor calidad cristalina, ambas beneficiosas p…
A Catalyst Designed for the Enantioselective Construction of Methyl- and Alkyl-Substituted Tertiary Stereocenters
2015
Tertiary methyl-substituted stereocenters are present in numerous biologically active natural products. Reported herein is a catalytic enantioselective method for accessing these chiral building blocks using the Mukaiyama-Michael reaction between silyl ketene thioacetals and acrolein. To enable remote enantioface control on the nucleophile, a new iminium catalyst, optimized by three-parameter tuning and by identifying substituent effects on enantioselectivity, was designed. The catalytic process allows rapid access to chiral thioesters, amides, aldehydes, and ketones bearing an α-methyl stereocenter with excellent enantioselectivities, and allowed rapid access to the C4-C13 segment of (-)-b…
Validación de la biopsia selectiva de ganglio centinela como método de estadificación axilar postneoadyuvancia en pacientes con cáncer de mama y axil…
2021
La biopsia selectiva de ganglio centinela (BSGC) es la técnica de elección para la estadificación axilar en pacientes con cáncer de mama que no reciben tratamiento neoadyuvante (NA), así como en aquellas con axila negativa (N0) al diagnóstico que reciben NA. En pacientes con afectación axilar al diagnóstico (N+) que reciben NA, la realización de BSGC todavía sigue generando debate, debido fundamentalmente a la mayor tasa de falsos negativos (TFN) reportada en los primeros estudios realizados, recomendando todavía la mayoría de guías actuales la realización de linfadenectomía axilar (LA). Algunos procedimientos recientemente descritos, como el marcaje del ganglio inicialmente afecto y su loc…