Search results for " correlation"

Dye-Labeled Poly(organosiloxane) Microgels with Core−Shell Architecture

1999

Poly(organosiloxane) microgels are highly cross-linked rather monodisperse spherical particles of radius about 10 nm. Using a functionalized silane comonomer, i.e., (chlorobenzyl)trimethoxysilane, model particles suitable for studies in colloid physics are available:  photoreactive and fluorescent dyes can be covalently bound within the microgels to prepare tracers for diffusion studies using forced Rayleigh scattering (FRS) and fluorescence correlation spectroscopy (FCS). For the application as tracer particles, it is important not to influence the diffusion behavior by the coupled chromophores. Therefore, functionalized precursors with a core−shell architecture are used to minimize labeli…

Isometric endurance test of the cervical flexor muscles - Reliability and normative reference values.

2017

Abstract Objective To obtain reference values for the isometric endurance test (IET) of the cervical flexor muscles, investigate its reproducibility, and compare the results with the maximal isometric strength test (MIST) of the cervical flexor muscles. Design Cross-sectional non-comparative study with single group repeated measurements. Methods Altogether 219 healthy females aged 20–59 years volunteered to participate in the study. The IET was performed in the supine position and MIST seated. The reproducibility was evaluated by the intraclass correlation coefficient (ICC) and an analysis described by Bland and Altman. The relationship between the two measuring methods was evaluated by Pea…

Experimental investigation on the effectiveness of basalt-fibre strengthening systems for confining masonry elements

L’impiego di materiali compositi per il rinforzo di colonne in muratura è diventato una pratica ampiamente diffusa nel corso degli ultimi decenni. Questa tecnica, che consiste generalmente nell’applicazione di materiali polimerici fibrorinforzati (Fibre Reinforced Polymer-FRP), ha mostrato buone potenzialità, essendo in grado di garantire notevoli incrementi di resistenza e duttilità dell’elemento rinforzato, grazie ad un’azione di confinamento passivo. Tuttavia, l’impiego di compositi a matrice polimerica presenta alcuni limiti legati soprattutto alle prestazioni delle resine epossidiche, che a causa della loro natura sintetica danno luogo a problemi di compatibilità con il supporto murari…

Perdió el libro que se compró / había comprado pocos días antes: Reflexiones iniciales en torno al saber gramatical sobre los tiempos verbales del pa…

2007

Carmen.Rdez-Gonzalo@uv.es La alternancia entre los tiempos verbales del pasado en textos escritos exige tener en cuenta diferencias aspectuales poco presentes en el español hablado. Según López García (2005: 162), el sistema de cinco tiempos simples (vengo, venía, vine, vendría, vendré) cubre las necesidades expresivas de los hispanohablantes, aunque los niños emplean menos y muchos hablantes adultos raramente usan otras formas. Los problemas se plantean cuando en lugar de hablar español necesitamos escribirlo y leerlo. Esta necesidad cambia por completo el inventario de tiempos ya que, para articular un texto es preciso dejar muy claro que unos acontecimientos ocurren antes o después de ot…

CCSD-CTOCD static dipole shielding polarizability for quantification of the chiral NMR effects in oxaziridine derivatives

2014

Chiral discrimination by nuclear magnetic resonance (NMR) spectroscopy might be achieved through the pseudo-scalar derived from the dipole shielding polarizability tensor. Coupled Cluster Singles and Doubles-Quadratic Response (CCSD-QR) calculations inside the continuous translation of the origin of the current density formalism have been carried out to determine the effects of basis set, electron correlation, and gauge translation on the determination of this magnitude in oxaziridine derivatives. Inclusion of electronic correlation is needed for adequately describing the pseudo-scalar for the heavier nuclei, making CCSD a rigorous and affordable method to compute these high order propertie…

Hidden Pursuits: Evaluating Gaze-selection via Pursuits when the Stimuli's Trajectory is Partially Hidden

2018

The idea behind gaze interaction using Pursuits is to leverage the human's smooth pursuit eye movements performed when following moving targets. However, humans can also anticipate where a moving target would reappear if it temporarily hides from their view. In this work, we investigate how well users can select targets using Pursuits in cases where the target's trajectory is partially invisible (HiddenPursuits): e.g., can users select a moving target that temporarily hides behind another object? Although HiddenPursuits was not studied in the context of interaction before, understanding how well users can perform HiddenPursuits presents numerous opportunities, particularly for small interfa…

Automatic left ventricle volume calculation with explainability through a deep learning weak-supervision methodology

2021

[EN] Background and objective: Magnetic resonance imaging is the most reliable imaging technique to assess the heart. More specifically there is great importance in the analysis of the left ventricle, as the main pathologies directly affect this region. In order to characterize the left ventricle, it is necessary to extract its volume. In this work we present a neural network architecture that is capable of directly estimating the left ventricle volume in short axis cine Magnetic Resonance Imaging in the end-diastolic frame and provide a segmentation of the region which is the basis of the volume calculation, thus offering explain-ability to the estimated value. Methods: The network was des…

A methodology to assess the intrinsic discriminative ability of a distance function and its interplay with clustering algorithms for microarray data …

2013

Abstract Background Clustering is one of the most well known activities in scientific investigation and the object of research in many disciplines, ranging from statistics to computer science. Following Handl et al., it can be summarized as a three step process: (1) choice of a distance function; (2) choice of a clustering algorithm; (3) choice of a validation method. Although such a purist approach to clustering is hardly seen in many areas of science, genomic data require that level of attention, if inferences made from cluster analysis have to be of some relevance to biomedical research. Results A procedure is proposed for the assessment of the discriminative ability of a distance functi…

Fluorescence Decay Time of Single Semiconductor Nanocrystals

2002

We present fluorescence decay measurements of single ZnS covered CdSe nanocrystals. It is shown that the fluorescence decay time is fluctuating during the investigation leading to a multiexponential decay even for a single nanocrystal. In combination with measurements of the fluorescence blinking behavior we find that a high fluorescence intensity is correlated with a long fluorescence decay time. This is consistent with a model of fluctuating nonradiative decay channels leading to variable dynamic quenching processes of the excited state.

Realistic investigations of correlated electron systems with LDA + DMFT

2006

Conventional band structure calculations in the local density approximation (LDA) [1–3] are highly successful for many materials, but miss important aspects of the physics and energetics of strongly correlated electron systems, such as transition metal oxides and f-electron systems displaying, e.g., Mott insulating and heavy quasiparticle behavior. In this respect, the LDA + DMFT approach which merges LDA with a modern many-body approach, the dynamical mean-field theory (DMFT), has proved to be a breakthrough for the realistic modeling of correlated materials. Depending on the strength of the electronic correlation, a LDA + DMFT calculation yields the weakly correlated LDA results, a strong…