Spatially-variant noise filtering in magnetic resonance imaging : a consensus-based approach

In order to accelerate the acquisition process in multiple-coil Magnetic Resonance scanners, parallel techniques were developed. These techniques reduce the acquisition time via a sub-sampling of the k-space and a reconstruction process. From a signal and noise perspective, the use of a acceleration techniques modify the structure of the noise within the image. In the most common algorithms, like SENSE, the final magnitude image after the reconstruction is known to follow a Rician distribution for each pixel, just like single coil systems. However, the noise is spatially non-stationary, i.e. the variance of noise becomes x-dependent. This effect can also be found in magnitude images due to other processing inside the scanner. In this work we propose a method to adapt well-known noise filtering techniques initially designed to deal with stationary noise to the case of spatially variant Rician noise. The method copes with inaccurate estimates of variant noise patterns in the image, showing its robustness in realistic cases. The method employs a consensus strategy in conjunction with a set of aggregation functions and a penalty function. Multiple possible outputs are generated for each pixel assuming different unknown input parameters. The consensus approach merges them into a unique filtered image. As a filtering technique, we have selected the Linear Minimum Mean Square Error (LMMSE) estimator for Rician data, which has been used to test our methodology due to its simplicity and robustness. Results with synthetic and in vivo data confirm the good behavior of our approach

Realización de vídeo de enseñanza online y presencial para prácticas por internet y presenciales de la radiografía de muñeca como método para valorar el desarrollo óseo

Se ha realizado un video en el que el alumno visualiza los diferentes estadios de desarrollo que tienen lugar en la osificación de la muñeca y puede aprender cómo utilizar la radiografía de muñeca para determinar el momento de desarrollo del paciente

Geoheritage as an educational resource and educational resources as heritage

El presente trabajo muestra una compilación de experiencias didácticas que emplean el patrimonio geológico como herramienta pedagógica en la enseñanza de las materias relacionadas con las Ciencias de la Tierra. El objetivo de todas ellas es acercar al alumnado al conocimiento y comprensión de los procesos que acontecen en nuestro planeta, con la finalidad de lograr un acercamiento y sensibilización hacia los mismos. Las seis propuestas seleccionadas presentan variedad en cuanto al contexto territorial de desarrollo de las actividades, a los contenidos y niveles trabajados (desde Enseñanza Secundaria hasta estudios universitarios) y a las metodologías utilizadas para la transmisión de dichos contenidos. Dentro de esta diversidad pueden distinguirse dos grupos de actividades diferentes. El primero de ellos se basa en el desarrollo de experiencias pedagógicas en localidades cuyas características geológicas resultan modélicas, únicas y/o espectaculares. Por el contrario, el segundo conjunto de actividades se centra en el trabajo de los recursos geológicos presentes en el entorno próximo del centro educativo. En ellas se explota su valor patrimonial, es decir, su potencial didáctico para abordar el estudio de la historia geológica del territorio. A través de las actividades incluidas en este compendio, se evidencia la validez de ambos tipos de aproximaciones y, al mismo tiempo, se debaten y realzan algunas de las virtudes más destacables de cada una de ellas. De esta manera, este catálogo podría resultar útil e inspirador para posibles planteamientos futuros.This manuscript presents a compilation of didactic experiences, which address the teaching of Earth Sciences through the knowledge of geological heritage. The aim of these proposals is to promote students’ comprehension of the Earth processes so that they may develop a positive attitude towards them. The six activities chosen offer a catalogue with a variety of sites, methodologies, contents and levels. Within this variety, the activities shown can be gathered into two separate groups. On the one hand, the first group collects experiences, which use geological heritage, i.e., the experiences are developed in places whose geological content is exemplary, unique and/or spectacular. On the other hand, the second group is focused on the geologic resources in the neighborhood of the school. These sites have heritage value, that is, an educational value for studying the geologic history of their territory. The activities drawn together show that both viewpoints are useful, and the benefits of each are pointed out. Consequently, this catalogue might be useful and inspiring for forthcoming attempts in this field

Las unidades de deshabituación tabáquica como oportunidad para el diagnóstico de EPOC: el proyecto 1000-200

This study received an unconditional grant from GlaxoSmithKline Laboratories Spain

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Jet properties in PbPb and pp collisions at sN N=5.02 \sqrt{s_{\mathrm{N}\;\mathrm{N}}}=5.02 TeV

Modifications of the properties of jets in PbPb collisions, relative to those in pp collisions, are studied at a nucleon-nucleon center-of-mass energy of s NN − − − − √ =5.02 sNN=5.02 TeV via correlations of charged particles with the jet axis in relative pseudorapidity (Δη), relative azimuth (Δϕ), and relative angular distance from the jet axis Δr=(Δη) 2 +(Δϕ) 2 − − − − − − − − − − − − √ Δr=(Δη)2+(Δϕ)2 . This analysis uses data collected with the CMS detector at the LHC, corresponding to integrated luminosities of 404 μb−1 and 27.4 pb−1 for PbPb and pp collisions, respectively. Charged particle number densities, jet fragmentation functions, and jet shapes are presented as a function of PbPb collision centrality and charged-particle track transverse momentum, providing a differential description of jet modifications due to interactions with the quark-gluon plasma

Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

Peer reviewe

Search for high-mass resonances in dilepton final states in proton-proton collisions at root s=13 TeV

A search is presented for new high-mass resonances decaying into electron or muon pairs. The search uses proton-proton collision data at a centre-of-mass energy of 13TeV collected by the CMS experiment at the LHC in 2016, corresponding to an integrated luminosity of 36 fb(-1). Observations are in agreement with standard model expectations. Upper limits on the product of a new resonance production cross section and branching fraction to dileptons are calculated in a model-independent manner. This permits the interpretation of the limits in models predicting a narrow dielectron or dimuon resonance. A scan of different intrinsic width hypotheses is performed. Limits are set on the masses of various hypothetical particles. For the Z(SSM)' (Z(psi)') particle, which arises in the sequential standard model (superstring-inspired model), a lower mass limit of 4.50 (3.90) TeV is set at 95% confidence level. The lightest Kaluza-Klein graviton arising in the Randall-Sundrum model of extra dimensions, with coupling parameters k/(M) over bar (Pl) of 0.01, 0.05, and 0.10, is excluded at 95% con fi dence level below 2.10, 3.65, and 4.25TeV, respectively. In a simpli fi ed model of dark matter production via a vector or axial vector mediator, limits at 95% con fi dence level are obtained on the masses of the dark matter particle and its mediator.Peer reviewe

Evidence for associated production of a Higgs boson with a top quark pair in final states with electrons, muons, and hadronically decaying τ leptons at s=13 \sqrt{s}=13 TeV

Results of a search for the standard model Higgs boson produced in association with a top quark pair (tt¯H) in final states with electrons, muons, and hadronically decaying τ leptons are presented. The analyzed data set corresponds to an integrated luminosity of 35.9 fb−1 recorded in proton-proton collisions at s√=13 TeV by the CMS experiment in 2016. The sensitivity of the search is improved by using matrix element and machine learning methods to separate the signal from backgrounds. The measured signal rate amounts to 1.23 − 0.43 + 0.45 times the production rate expected in the standard model, with an observed (expected) significance of 3.2σ (2.8σ), which represents evidence for tt¯H production in those final states. An upper limit on the signal rate of 2.1 times the standard model production rate is set at 95% confidence level