175 research outputs found
Propuesta de sistema para el estudio de la autopercepción de la persona en el entorno digital
En el presente estudio se tiene como objetivo evaluar la autopercepción de las
características de personalidad en personas mayores de 18 años inmersas en el
entorno digital de un videojuego multiplayer online battle arena (MOBA), mediante
la propuesta de una adaptación del test de personalidad de Millon III a este entorno.
Posteriormente a la determinación de aquellos factores que participan en el proceso
de autopercepción de la persona, se ha hecho el descarte de algunos indicadores
e items del test original que no se podrán en la adaptación del test por involucrar
aspectos psicométricos y dependencias que se han considerado inadaptables, pero
que no alteran ni modifican los resultados de ningún otro indicador o medición de
estos, haciendo uso de la segunda edición de las directrices de la comisión
internacional para la traducción y adaptación de los test. Se ha aplicado tanto el
test original, como el test adaptado a un sector inmerso del juego para
posteriormente poder evaluar los resultados, los cuales definirán los niveles de
autopercepción según sus indicadores
Complex diffusion-weighted image estimation via matrix recovery under general noise models
We propose a patch-based singular value shrinkage method for diffusion
magnetic resonance image estimation targeted at low signal to noise ratio and
accelerated acquisitions. It operates on the complex data resulting from a
sensitivity encoding reconstruction, where asymptotically optimal signal
recovery guarantees can be attained by modeling the noise propagation in the
reconstruction and subsequently simulating or calculating the limit singular
value spectrum. Simple strategies are presented to deal with phase
inconsistencies and optimize patch construction. The pertinence of our
contributions is quantitatively validated on synthetic data, an in vivo adult
example, and challenging neonatal and fetal cohorts. Our methodology is
compared with related approaches, which generally operate on magnitude-only
data and use data-based noise level estimation and singular value truncation.
Visual examples are provided to illustrate effectiveness in generating denoised
and debiased diffusion estimates with well preserved spatial and diffusion
detail.Comment: 26 pages, 9 figure
Store-and-Forward Teledermatology Using Mobile Phones: Clinical Efficacy in a Rural Primary Healthcare Centre Free Clinic Setting
Background: Technological advances increase the feasibility of mobile-phone teledermatology (mdermatology). By saving time and costs, underserved areas lacking dermatologists may benefit greatly. Objectives: To assess the clinical efficacy of mobile-phone store-and-forward mdermatology compared to face-to-face consultation. Methods: Patients from a rural health centre in Batangas were randomised to either mdermatology or face-to-face group. In the mdermatology group, a general practitioner (GP) assessed patients, took photographs using a cell phone camera and sent these via e-mail accessed via the GP’s mobile phone to the mdermatologist’s mobile phone. In the face-to-face group, the GP assessed patients and then referred them to the face-to-face dermatologist. Both the mdermatologist and face-to-face dermatologist provided assessments and plans for patients in their respective groups. Clinical outcomes were assessed after two and four weeks. Results: A total of 123 patients were included, with 60 participants in the mdermatology group and 63 in the face-to-face group. In both groups, most participants improved. There were no significant differences in clinical outcomes assessed by GPs (p=0.074), dermatologists (p=0.172), or participants (p=0.405). The diagnostic strength of agreement between the GP and the dermatologist differed between the two groups (Cohen’s κ=0.5775 vs. 0.2735), but management concordance was similar (p=0.775). Conclusion: Store-and-forward teledermatology using mobile phones in the dermatologic management of patients in a rural primary healthcare centre free clinic setting is feasible. This study did not find mobile teledermatology inferior to face-to-face consultation
Influencia de un escáner de mesa, usado para digitalizar, en la determinación de dosis por película radiocrómica
Introduction: The precision in determination of the dose using radiochromic films as a dosimeter is influenced by three main aspects: the dose delivery capacity of the radiation unit, the response of the film when exposed to radiation, and the capacity of the scanner to digitize the films and transform them into intensity values. This work focuses on the last aspect. Objective: To establish a methodology for the evaluation of the variability of the dose due to the repeatability of scans and the position of the film in the scanning area, under calibration conditions of radiochromic films for three different resolutions. Methods: Pieces of EBT3 radiochromic films were irradiated at 11 different dose values, which were scanned at 3 different resolutions, creating a calibration curve for each resolution. These curves are used to determine dose variations due to film position in the scan area and scan repeatability; for this purpose, we measured 5 dose values per film, for each of 9 images by resolution, with a total of 27 images. Results: In the three resolutions studied, uncertainties below 1% were found due to variation in the position of the film in the scanning area and uncertainty below 2% in the case of scan repeatability. Conclusions: The values obtained from the sources of uncertainty studied were not negligible; therefore, they must be included in the total uncertainty budget of the radiochromic film dose measurement process. Working with dose values eliminates the dependence on the resolution.Introducción: La precisión en la determinación de la dosis utilizando películas radiocrómicas como dosímetro, se encuentra influenciada por: la capacidad del equipo emisor de radiación ionizante al dar la dosis deseada, la respuesta de la película al ser expuesta a la radiación y a la capacidad del escáner para digitalizar las películas y transformarlas en valores de intensidad. Este trabajo se enfoca en este último aspecto. Objetivo: Establecer una metodología para la evaluación de la variabilidad de la dosis debido a la repetibilidad de escaneos y a la posición de la película en el área de escaneo, en condiciones de calibración de las películas radiocrómicas para tres resoluciones distintas. Métodos: Irradiamos piezas de películas radiocrómicas EBT3 a 11 valores diferentes de dosis, las cuales escaneamos a tres resoluciones diferentes, creando una curva de calibración para cada resolución. Estas curvas se utilizan para determinar las variaciones en la dosis debido a la posición de la película en el área de escaneo y a la repetibilidad de escaneo; lo anterior, a partir de cinco valores de dosis medidos por película, para cada una de las nueve imágenes tomadas por resolución, siendo en total 27 imágenes. Resultados: Para las tres resoluciones estudiadas, determinamos: las curvas de calibración, incertidumbres por debajo del 1% debido a la variación de la posición de la película en el área de escaneo e incertidumbre por debajo del 2% para el caso de repetibilidad de escaneos. Conclusión: Los valores obtenidos de las fuentes de incertidumbre no fueron despreciables: deben incluirse en el presupuesto total de incertidumbre de la medición. Al usar valores de dosi,s y no intensidad o densidad óptica, se elimina la dependencia de la resolución
Emerging functional connectivity differences in newborn infants vulnerable to autism spectrum disorders
3-3-1 Models at Electroweak Scale
We show that in 3-3-1 models there exist a natural relation among the
coupling constant , the electroweak mixing angle , the
mass of the , and one of the vacuum expectation values, which implies that
those models can be realized at low energy scales and, in particular, even at
the electroweak scale. So that, being that symmetries realized in Nature, new
physics may be really just around the corner.Comment: 10 pages, version to be published in Physics Letters
Investigating altered brain development in infants with congenital heart disease using tensor-based morphometry
Cortactin regulates cofilin and N-WASp activities to control the stages of invadopodium assembly and maturation
Invadopodia are matrix-degrading membrane protrusions in invasive carcinoma cells. The mechanisms regulating invadopodium assembly and maturation are not understood. We have dissected the stages of invadopodium assembly and maturation and show that invadopodia use cortactin phosphorylation as a master switch during these processes. In particular, cortactin phosphorylation was found to regulate cofilin and Arp2/3 complex–dependent actin polymerization. Cortactin directly binds cofilin and inhibits its severing activity. Cortactin phosphorylation is required to release this inhibition so cofilin can sever actin filaments to create barbed ends at invadopodia to support Arp2/3-dependent actin polymerization. After barbed end formation, cortactin is dephosphorylated, which blocks cofilin severing activity thereby stabilizing invadopodia. These findings identify novel mechanisms for actin polymerization in the invadopodia of metastatic carcinoma cells and define four distinct stages of invadopodium assembly and maturation consisting of invadopodium precursor formation, actin polymerization, stabilization, and matrix degradation
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