20,285 research outputs found
Multipartite purification protocols: upper and optimal bounds
A method for producing an upper bound for all multipartite purification
protocols is devised, based on knowing the optimal protocol for purifying
bipartite states. When applied to a range of noise models, both local and
correlated, the optimality of certain protocols can be demonstrated for a
variety of graph and valence bond states.Comment: 15 pages, 16 figures. v3: published versio
Psychological type preferences of female Bible College students in England
A sample of 122 female students attending a Pentecostal Bible College in England completed Form G (Anglicised) of the Myers-Briggs Type Indicator (MBTI). The data demonstrated preferences for extraversion over introversion, for sensing over intuition, for feeling over thinking, and for judging over perceiving. The predominant type was ISFJ (16%), followed by ESFJ (12%). Comparison with the population norms demonstrated an over-representation of intuitives among this sample of Bible College students
An efficient implementation of an implicit FEM scheme for fractional-in-space reaction-diffusion equations
Fractional differential equations are becoming increasingly used as a modelling tool for processes with anomalous diffusion or spatial heterogeneity. However, the presence of a fractional differential operator causes memory (time fractional) or nonlocality (space fractional) issues, which impose a number of computational constraints. In this paper we develop efficient, scalable techniques for solving fractional-in-space reaction diffusion equations using the finite element method on both structured and unstructured grids, and robust techniques for computing the fractional power of a matrix times a vector. Our approach is show-cased by solving the fractional Fisher and fractional Allen-Cahn reaction-diffusion equations in two and three spatial dimensions, and analysing the speed of the travelling wave and size of the interface in terms of the fractional power of the underlying Laplacian operator
Fourier spectral methods for fractional-in-space reaction-diffusion equations
Fractional differential equations are becoming increasingly used as a powerful modelling approach for understanding the many aspects of nonlocality and spatial heterogeneity. However, the numerical approximation of these models is computationally demanding and imposes a number of computational constraints. In this paper, we introduce Fourier spectral methods as an attractive and easy-to-code alternative for the integration of fractional-in-space reactiondiffusion equations. The main advantages of the proposed schemes is that they yield a fully diagonal representation of the fractional operator, with increased accuracy and efficiency when compared to low-order counterparts, and a completely straightforward extension to two and three spatial dimensions. Our approach is show-cased by solving several problems of practical interest, including the fractional Allen–Cahn, FitzHugh–Nagumo and Gray–Scott models,together with an analysis of the properties of these systems in terms of the fractional power of the underlying Laplacian operator
Mixed mode pattern in Doublefoot mutant mouse limb - Turing reaction-diffusion model on a growing domain during limb development
It has been suggested that the Turing reaction–diffusion model on a growing domain is applicable during limb development, but experimental evidence for this hypothesis has been lacking. In the present study, we found that in Doublefoot mutant mice, which have supernumerary digits due to overexpansion of the limb bud, thin digits exist in the proximal part of the hand or foot, which sometimes become normal abruptly at the distal part. We found that exactly the same behaviour can be reproduced by numerical simulation of the simplest possible Turing reaction–diffusion model on a growing domain. We analytically showed that this pattern is related to the saturation of activator kinetics in the model. Furthermore, we showed that a number of experimentally observed phenomena in this system can be explained within the context of a Turing reaction–diffusion model. Finally, we make some experimentally testable predictions
Cosmid Cloning of Five \u3cem\u3eZymomonas trp\u3c/em\u3e Genes by Complementation of \u3cem\u3eEscherichia coli\u3c/em\u3e and \u3cem\u3ePseudomonas putida trp\u3c/em\u3e Mutants
A library of Zymomonas mobilis genomic DNA was constructed in the broad-host-range cosmid pLAFR1. The library was mobilized into a variety of Escherichia coli and Pseudomonas putida trp mutants by using the helper plasmid pRK2013. Five Z. mobilis trp genes were identified by the ability to complement the trp mutants. The trpF, trpB, and trpA genes were on one cosmid, while the trpD and trpC genes were on two separate cosmids. The organization of the Z. mobilis trp genes seems to be similar to the organization found in Rhizobium spp., Acinetobacter calcoaceticus, and Pseudomonas acidovorans. The trpF, trpB, and trpA genes appeared to be linked, but they were not closely associated with trpD or trpC genes
Elasticity of a contact-line and avalanche-size distribution at depinning
Motivated by recent experiments, we extend the Joanny-deGennes calculation of
the elasticity of a contact line to an arbitrary contact angle and an arbitrary
plate inclination in presence of gravity. This requires a diagonalization of
the elastic modes around the non-linear equilibrium profile, which is carried
out exactly. We then make detailed predictions for the avalanche-size
distribution at quasi-static depinning: we study how the universal (i.e.
short-scale independent) rescaled size distribution and the ratio of moments of
local to global avalanches depend on the precise form of the elastic kernel.Comment: 15 pages, 11 figure
Psychological type preferences of male British Assemblies of God Theological College students: tough-minded or tender-hearted?
Psychological type theory proposes that people make decisions through using one of two dichotomous judging functions (thinking and feeling). People who prefer thinking make judgements based on impersonal logic and tend to be objective and tough-minded, while people who prefer feeling make judgements based on personal values and tend to be compassionate and tender-hearted. This study explores the notion that the judging functions are key predictors of individual differences in terms of religiosity. The psychological type preferences of a sample of 190 male Assemblies of God bible college students were assessed using Form G (Anglicised) of the Myers-Briggs Type Indicator. The data revealed preferences for thinking over feeling, and the implications of this finding are explored
Simulation of cell movement through evolving environment: a fictitious domain approach
A numerical method for simulating the movement of unicellular organisms which respond to chemical signals is presented. Cells are modelled as objects of finite size while the extracellular space is described by reaction-diffusion partial differential equations. This modular simulation allows the implementation of different models at the different scales encountered in cell biology and couples them in one single framework. The global computational cost is contained thanks to the use of the fictitious domain method for finite elements, allowing the efficient solve of partial differential equations in moving domains. Finally, a mixed formulation is adopted in order to better monitor the flux of chemicals, specifically at the interface between the cells and the extracellular domain
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