Search results for "Diffusion"

Antibacterial activity of different root canal sealers against Enterococcus faecalis

2017

Background The aim of the present study was to compare in vitro the antimicrobial activity of different root canal sealers against Enterococcus faecalis, prior and subsequent to setting. Material and methods Agar diffusion test (ADT) was used for evaluating the antibacterial activity of non-set sealer while the direct contact test (DCT) was used for after setting. Results ADT: Except for TotalFill BC Sealer all the others sealers tested showed antibacterial activity. BioRoot™RCS, MTA Fillapex and Sealapex Root Canal Sealer showed the lowest antibacterial activity, a significant increase in antibacterial effect for both Pulp Canal Sealer™ and AH plus sealers were found. Significantly higher …

Nonlinear data description with Principal Polynomial Analysis

2012

Principal Component Analysis (PCA) has been widely used for manifold description and dimensionality reduction. Performance of PCA is however hampered when data exhibits nonlinear feature relations. In this work, we propose a new framework for manifold learning based on the use of a sequence of Principal Polynomials that capture the eventually nonlinear nature of the data. The proposed Principal Polynomial Analysis (PPA) is shown to generalize PCA. Unlike recently proposed nonlinear methods (e.g. spectral/kernel methods and projection pursuit techniques, neural networks), PPA features are easily interpretable and the method leads to a fully invertible transform, which is a desirable property…

How and Why Some Issues Spread Fast In Social Media

2015

This paper brings together current insights from various disciplines into the spreading of social media post. By a structured literature review of peer-reviewed literature 39 recent articles on diffusion in social media were located. The search spanned 10 years, although all the papers were published after 2009, indicating that the examination and observation of spread patterns in social media is still in an early stage. The analys is focused on spread patterns and factors that may explain how rapidly issues spread in the online environment. Based on the findings, from an organizational perspective a model is constructed and directions for future research are suggested. The model focuses on…

Comparative evaluation of data preprocessing software tools to increase efficiency and accuracy in diffusion kurtosis imaging

2016

High performance of intravoxel incoherent motion diffusion MRI in detecting viral hepatitis-b induced liver fibrosis.

2019

Background: Recently a small cohort study demonstrated that intravoxel incoherent motion (IVIM) diffusion MRI can detect early stage liver fibrosis. Using modified IVIM data acquisition parameters, the current study aims to confirm this finding. Methods: Twenty-six healthy volunteers, three patients of chronic viral hepatitis-b but without fibrosis and one mild liver steatosis subject, and 12 viral hepatitis-b patients with fibrosis (stage 1–2=7, stage 3–4=5) were included in this study. With a 1.5-T MR scanner and respiration-gating, IVIM diffusion imaging was acquired using a single-shot echo-planar sequence with a b -value series of 2, 0, 1, 15, 20, 30, 45, 50, 60, 80, 100, 200, 300, 600…

Sport and Quality of Life

2022

Negli ultimi trent’anni lo sport ha assunto un significato molto rilevante nella vita delle persone e, seppure con notevoli differenze, sia nei paesi a sviluppo economico avanzato, sia in quelli in via di sviluppo. A livello individuale, esso ha costituito un’area di investimento identitario quando ha assunto la forma di sport spettacolo del quale fruire, alimentando la pratica del tifo e il fandom o costituendo il modello di uno stile di vita vincente; ma anche quando ha assunto la forma di pratica del tempo libero attraverso la quale tenersi in forma, facendo crescere, in questo caso, la diffusione di una cultura della salute e del benessere. Si tratta di due modalità di approcciare al co…

La distribution des tuiles estampillées de la VIIIe légion Augusta autour de Mirebeau-sur-Bèze (Côte-d'Or, France)

2011

The 8th Augustan Legion was installed at Mirebeau-sur-Bèze (Côte-d'Or) after 70 AD following the troubles that arose with the Lingons. It remained there until the time of Domitian, a period of roughly twenty years, during which time the soldiers produced tiles stamped with the name of the legion. Analysis of the dispersion of the tiles in the region around Mirebeau shows that they followed the communication routes. Consideration of the contexts in which these tiles were used, their number on each site and the resources necessary to manufacture them reveals that the 8th Legion may have played a significant role in the diffusion and adoption of tiled roofs, a construction technique that was t…

Cation Diffusion and Segregation at the Interface between Samarium-Doped Ceria and LSCF or LSFCu Cathodes Investigated with X-ray Microspectroscopy

2017

The chemical compatibility between electrolytes and electrodes is an extremely important aspect governing the overall impedance of solid-oxide cells. Because these devices work at elevated temperatures, they are especially prone to cation interdiffusion between the cell components, possibly resulting in secondary insulating phases. In this work, we applied X-ray microspectroscopy to study the interface between a samarium-doped ceria (SDC) electrolyte and lanthanum ferrite cathodes (La0.4Sr0.6Fe0.8Cu0.2O3(LSFCu); La0.9Sr0.1Fe0.85Co0.15O3(LSCF)), at a submicrometric level. This technique allows to combine the information about the diffusion profiles of cations on the scale of several micromet…

Influence of the U3O7 domain structure on cracking during the oxidation of UO2

2010

Abstract Cracking is observed when a UO 2 single crystal is oxidised in air. Previous studies led to the hypothesis that cracking occurs once a critical depth of U 3 O 7 oxidised layer is reached. We present some μ-Laue X-ray diffraction results, which evidence that the U 3 O 7 layer, grown by topotaxy on UO 2 , is made of domains with different crystalline orientations. This observation was used to perform a modelling of oxidation coupling chemical and mechanical parameters, which showed that the domain patterning induces stress localisation. This result is discussed in comparison with stress localisation observed in thin layer deposited on a substrate and used to propose an interpretation…

The Influence of Oxygen Affinity of Blood and Cerebral Blood Flow on Cerebral Oxygen Supply

1969

The quantity of oxygen transported, per unit of time, by the blood to the brain, is determined by the blood flow, the oxygen capacity, and the oxygen affinity of the blood. The O2-exchange between the blood and the tissue cells depends mainly on the oxygen transport characteristics of the blood and the O2 diffusion conditions in the blood and tissue.