Search results for "PERSISTENCE"
showing 10 items of 243 documents
Gendered power relations in the digital age : an analysis of Japanese women’s media choice and use within a global context
2021
This study investigates the persistence of gendered choice and use of media, particularly in Japanese domestic settings. It shows how women’s significant presence in the digital media environment does not necessarily translate into substantial changes in gendered power dynamics in choosing and using particular media for certain purposes at home. This project’s authors, researchers from Argentina, Finland, Israel, Japan, and the US, analyzed interview data from Japan by drawing on the Foucauldian concept of micro-level power, which is categorized into three main types: personal authority, media affordances, and space-time constellations. Through this process, we interviewed 77 individuals, r…
Reconciling conflicting predictions about transience and persistence of management concepts in management fashion theory and new institutionalism
2021
PurposeAlthough drawing from neoinstitutional theoretical apparatus and ontology, management fashion theory is understood as a theory that explains the transitory nature of popular ideas and practices while institutional theory explains their stabilization, persistence and further institutionalization. In a nutshell, it seems that being opposed to each other, these two theories describe and predict different, incommensurable diffusion trajectories and organizational behaviour patterns. The purpose of this paper is to unify these two competing perspectives.Design/methodology/approachThis paper makes an attempt toward further unification of management fashion theory with new institutionalism …
FUNCIONES EJECUTIVAS Y MOTIVACIÓN DE NIÑOS CON TRASTORNO DE ESPECTRO AUTISTA (TEA) Y TRASTORNO POR DÉFICIT DE ATENCIÓN CON HIPERACTIVIDAD (TDAH)
2016
Resumen Objetivos. Comparar el perfil de niños con trastorno del espectro autista (TEA) y niños con trastorno por déficit de atención con hiperactividad (TDAH), presentación combinada, en componentes del funcionamiento ejecutivo (FE) y en comportamientos que están asociados al aprendizaje. Método. Participaron en esta investigación 16 niños con un diagnóstico clínico de TDAH y 16 niños con un diagnóstico clínico de TEA con alto nivel de funcionamiento que habían sido diagnosticados en servicios de Neuropediatría de la Comunidad Valenciana. Las edades estaban comprendidas entre 7 y 11 años. El 94% eran varones y se encontraban escolarizados en aulas ordinarias, estando equiparados los dos …
Flexibility of phenylene oligomers revealed by single molecule spectroscopy
2006
The rigidity of a p-phenylene oligomer (p-terphenyl) has been investigated by single molecule confocal fluorescence microscopy. Two different rylene diimide dyes attached to the terminal positions of the oligomer allowed for wavelength selective excitation of the two chromophores. In combination with polarization modulation the spatial orientation of the transition dipoles of both end groups could be determined independently. We have analyzed 597 single molecules in two different polymer hosts, polymethylmethacrylate and Zeonex. On average we find a 22 degrees deviation from the linear gas phase geometry (T = 0 K), indicating a rather high flexibility of the p-phenylene oligomer independent…
Semi-flexible polymer chains in quasi-one-dimensional confinement: a Monte Carlo study on the square lattice
2013
Single semi-flexible polymer chains are modeled as self-avoiding walks (SAWs) on the square lattice with every 90° kink requiring an energy eb. While for eb = 0 this is the ordinary SAW, varying the parameter qb = exp(−eb/kBT) allows the variation of the effective persistence length p over about two decades. Using the pruned-enriched Rosenbluth method (PERM), chain lengths up to about N = 105 steps can be studied. In previous work it has already been shown that for contour lengths L = Nb (the bond length b is the lattice spacing) of order p a smooth crossover from rods to two-dimensional self-avoiding walks occurs, with radii R ∝ p1/4L3/4, the Gaussian regime predicted by the Kratky–Porod m…
Semiflexible polymers confined in a slit pore with attractive walls: two-dimensional liquid crystalline order versus capillary nematization
2017
Semiflexible polymers under good solvent conditions interacting with attractive planar surfaces are investigated by Molecular Dynamics (MD) simulations and classical Density Functional Theory (DFT). A bead-spring type potential complemented by a bending potential is used, allowing variation of chain stiffness from completely flexible coils to rod-like polymers whose persistence length by far exceeds their contour length. Solvent is only implicitly included, monomer-monomer interactions being purely repulsive, while two types of attractive wall-monomer interactions are considered: (i) a strongly attractive Mie-type potential, appropriate for a strictly structureless wall, and (ii) a corrugat…
Interfaces in polymer blends
2000
We investigate the structure and thermodynamics of interfaces in dense polymer blends using Monte Carlo (MC) simulations and self-consistent field (SCF) calculations. For structurally symmetric blends we find quantitative agreement between the MC simulations and the SCF calculations for excess quantities of the interface (e.g., interfacial tension or enrichment of copolymers at the interface). However, a quantitative comparison between profiles across the interface in the MC simulations and the SCF calculations has to take due account of capillary waves. While the profiles in the SCF calculations correspond to intrinsic profiles of a perfectly flat interface the local interfacial position f…
Topological effects in ring polymers. II. Influence of persistence length
1999
The interplay of topological constraints and persistence length of ring polymers in their own melt is investigated by means of dynamical Monte Carlo simulations of a three dimensional lattice model. We ask if the results are consistent with an asymptotically regime where the rings behave like (compact) {\em lattice animals} in a self-consistent network of topological constraints imposed by neighbouring rings. Tuning the persistence length provides an efficient route to increase the ring overlap required for this mean-field picture to hold: The {\em effective} Flory exponent for the ring size decreases down to $\nu \stackrel{<}{\sim} 1/3$ with increasing persistence length. Evidence is provi…
Röntgenkleinwinkelstreuung an isotaktischem und syndiotaktischem Polymethylmethacrylat in Lösung
1964
Die Form der Streukurven von gelosten Polymethylmethacrylaten (PMMA) ist eine Funktion der Taktizitat. In der Streukurve des syndiotaktischen PMMA last sich der Einflus einer Periodizitat erkennen. Eine quantitative Deutung gelingt durch Uberlagerung einer Helixstreukurve mit einer Knauelstreukurve. Dabei mus gesetzt werden H = 21 A, R = 4 A und a = 13 A (H und R sind die Identitatsperiode bzw. der Radius der Helix, a ist die Persistenzlange des Knauels.) Die Streukurve des isotaktischen PMMA zeigt nahezu den Verlauf, der fur Fadenknauel nach Kratky et al. [2–5] zu erwarten ist. Jedoch ist ein Intensitatsdefizit zu beobachten, das durch plausible Annahmen gedeutet wird. Als Persistenzlange …
Characteristic Length Scales and Radial Monomer Density Profiles of Molecular Bottle-Brushes: Simulation and Experiment
2010
Extensive Monte Carlo simulations are presented for bottle-brush polymers under good solvent conditions, using the bond fluctuation model on the simple cubic lattice. Varying the backbone length (from Nb = 67 to Nb = 259 effective monomers) as well as the side chain length (from N = 6 to N = 48), for a physically reasonable grafting density of one chain per backbone monomer, we find that the structure factor describing the total scattering from the bottle-brush provides an almost perfect match for some combinations of (Nb, N) to experimental data of Rathgeber et al. [J. Chem. Phys. 2005, 122, 124904], when we adjust the length scale of the simulation to reproduce the experimental gyration r…