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•The anisotropic effect of interface kinetics on particle growth is studied.•The asymptotic solution shows initially reversible inward growth of a particle.•The anisotropy of interface kinetics depresses growth along some directions.•The anisotropy of interface kinetics results in petal-like patterns of the particle.

• Anneal hardening phenomenon has been observed in dilute Al-doped al x cocrfemnni (x = 0, 0.1) high-entropy alloys, where peak hardness is reached at an annealing temperature of 500 °C (recrystallization temperature). • Dislocation substructure strengthening is identified to explain the observed annealing hardening phenomenon. • The dilute addition of al reduces the hardness/strength of the base alloy, this al induced softening could be associated with the presence of short-range cluster. Anneal hardening has been one of the approaches to improve mechanical properties of solid solution alloys with the face-centered cubic (FCC) structure, whereby a considerable strengthening can be attained by annealing of cold-worked alloys below the recrystallization temperature (T rx). Microscopically, this hardening effect has been ascribed to several mechanisms, i.e. solute segregation to defects (dislocation and stacking fault) and short-range chemical ordering, etc. However, none of these mechanisms can well explain the anneal hardening recently observed in phase-pure and coarse-grained FCC-structured high-entropy alloys (HEAs). Here we report the observations, using high-resolution electron channeling contrast imaging and transmission electron microscopy, of profuse and stable dislocation substructures in a cold-rolled CoCrFeMnNi HEA subject to an annealing below T rx. The dislocation substructures are observed to be thermally stable up to T rx , which could arise from the chemical complexity of the high-entropy system where certain elemental diffusion retardation occurs. The microstructure feature is markedly different from that of conventional dilute solid solution alloys, in which dislocation substructures gradually vanish by recovery during annealing, leading to a strength drop. Furthermore, dilute addition of 2 at.% Al leads to a reduction in both microhardness and yield strength of the cold-rolled and subsequently annealed (≤500 °C) HEA. This Al induced softening effect, could be associated with the anisotropic formation of dislocation substructure, resulting from enhanced dislocation planar slip due to glide plane softening effect. These findings suggest that the strength of HEAs can be tailored through the anneal hardening effect from dislocation substructure strengthening. [ABSTRACT FROM AUTHOR]

This paper presents a genetic-based approach to multi-criteria position and configuration optimisation of mobile manipulator systems. Optimisation criteria include obstacle avoidance, least joint torque norm, manipulability and joint torque distribution. Due to the competition among various criteria, the multi-criteria optimisation problem typically exhibits many local minima. The emphasis of the paper is put on using genetic algorithms to search for global optimum and solve the minilnax problem for torque distribution. Various simulations for a system including a three-link lnanipulator mounted on a mobile platform show that the proposed genetic algorithm approach performs better than conventional methods.

Purpose: Previous studies have demonstrated that partial outlet obstruction and acute overdistension of the rabbit bladder rapidly stimulate the activation of similar patterns of gene expression. Since bladder overdistension has been shown to reduce the blood flow of the bladder and since unilateral ischemia of rabbit bladder has been found to induce similar physiologic and histologic changes to the bladder as found in association with partial outlet obstruction, we tested whether experimental ischemia of the rabbit bladder could induce the same molecular response. Materials and Methods: Unilateral ischemia was created by surgically ligating the major arteries entering the rabbit bladder to one side. Bladders were recovered from control rabbits and from rabbits at 1 hour, 8 hours, 1, 3, or 7 days after unilateral ischemia and were divided into ischemic and nonischemic portions. These tissues were used for in vitro ^3^5S-methionine and^3 H-thymidine incorporation assays. Ribonucleic acids extracted from these tissues were examined by Northern blot assay for the expression of a number of different mRNA transcripts. Results: 1) Bladder DNA synthesis was elevated 4-fold at 24 hours after ischemia; 2) protein synthesis was increased 2-fold at 8 and 24 hours after ischemia; 3) early response genes (c-fos and c-jun) mRNAs were induced by 1 hour of ischemia; hsp-70 mRNA was highly induced by 8 hours of ischemia, and bFGF mRNA was elevated 3- to 5-fold by 8 hours of ischemia. Conclusion: The early molecular response of rabbit bladder to ischemia is similar to responses observed in bladder overdistension or partial outlet obstruction.