This study elaborates some examples of a simple evolutionary stochastic rate process where the population rate of change depends on the distribution of properties—so different cohorts change at different rates. We investigate the effect on the evolution arising from parametrized perturbations of uniformity for the initial inhomogeneity. The information geometric neighbourhood system yields also...

Introduction: Efficient mitigation of the radiofrequency (RF) inhomogeneity at high field using coil arrays relies on the accurate knowledge of the individual B1 maps. Based on these maps, algorithms using diverse k-space trajectories can return RF waveforms which homogenize the flip angle (FA). The algorithms initially aimed at counteracting the B1 inhomogeneity only [1, 2], until the spatial ...

Brain image segmentation is one of the most important parts of clinical diagnostic tools. However, accurate segmentation of brain images is a very difficult task due to the noise, inhomogeneity and sometimes deviation in brain images. Wells model incorporates the brain image segmentation and inhomogeneity correction into one framework to overcome influences from the intensity inhomogeneity and ...

Radiofrequency (RF) field inhomogeneity is an unavoidable problem in MRI, and it becomes severe at high magnetic fields due to the dependence of B1 on the sample. It leads to nonuniformities in image intensity and contrast, causing difficulties in quantitative interpretation and image segmentation. In this work, it is observed that with the fast low-angle shot (FLASH) sequence, which is often u...

We investigate the influence of inhomogeneity in the pairing coupling constant U r on dirty BCS superconductors, focusing on Tc, the order parameter r , and the energy gap Eg r . Within mean-field theory, we find that when the length scale of the inhomogeneity is comparable to or larger than the coherence length, the ratio 2Eg /Tc is significantly reduced from that of a homogeneous superconduct...

We study the robustness and stability of the yeast cell regulatory network by using a general inhomogeneous discrete model. We find that inhomogeneity, on average, enhances the stability of the biggest attractor of the dynamics and that the large size of the basin of attraction is robust against changes in the parameters of inhomogeneity. We find that the most frequent orbit, which represents t...

Inhomogeneous media identification is the problem of determining the physical properties of an unknown inhomogeneity from its response to various interrogating modalities. This response, recorded in measured data, comes as a result of the interaction of the inhomogeneity with an exciting physical field. Inhomogeneous media identification is mathematically modeled as the problem of determining t...

The continuum model of dipolar solvation dynamics is reviewed. The effects of non-spherical molecular shapes, of non-Debye dielectric relaxation of the polar solvent and of dielectric inhomogeneity of the solvent around the solute dipole are investigated. Several new theoretical results are presented. It is found that our generalized continuum model, which takes into account the dielectric inho...

Introduction Understanding the cause of hair curliness is one of major isuues in the cosmetics field. We studied the nanostructure of curly hair fibers, and detected the lateral inhomogeneity of the arrangement of the intermediate filaments (IFs) in the cortex, which was associated with the fiber curvature [1]. In this study, the correlation between the macroscopic curliness and the microscopic...