Jialin Huang

The microstructures of cryogenically ball-milled Cu were investigated by high-resolution electron microscopy. It was found that the grain-size reduction is a dislocation-controlled continuous process which consists of the formation of small-angle grain boundaries , a gradual increase in misorientations as a result of accumulation of more dislocations and, finally, the formation of large-angle GBs. The GBs were generally curved, wavy or faceted, and heavily strained, which are typical characteristics of nanostructured materials. In addition, extrinsic dislocations were found in many GBs, indicating that most are in a high-energy non-equilibrium configuration, which is consistent with observations in equal-channel angular pressing processed Cu, Ni, and Al-Mg, repetitive corrugation and straightening processed Cu and room-temperature ball-milled Cu. These results support a still-disputed concept that GBs in nanostructured metals processed by severe plastic deformation are mostly in non-equilibrium states

In this study, the authors utilize mountain pass lemma, variational methods, regularization technique, and the Lyapunov function method to derive the unique existence of the positive classical stationary solution of a single-species ecosystem. Particularly, the geometric characteristic of saddle point in the mountain pass lemma guarantees that the equilibrium point is the ground state stationary solution of the ecosystem. Based on the obtained uniqueness result, the authors use the Lyapunov function method to derive the globally exponential stability criterion, which illuminates that under some suitable conditions, a certain internal competition is conducive to the global stability of the population, and a certain amount of family planning is conducive to the overall stability of the population. Most notably, the regularity technique of weak stationary solution employed in this study can also be applied to some existing literature related with time-delays reaction-diffusion systems for the purpose of regularization of weak solutions. Finally, an illuminative numerical example shows the effectiveness of the proposed methods.

To evaluate the success rate of CT-guided bone biopsies in metastatic castration-resistant prostate cancer and to investigate associated technical, imaging, and clinical parameters affecting diagnostic yields.Eighty CT-guided bone biopsy specimens were obtained from 72 men enrolled in a multicenter trial to identify mechanisms of resistance in mCRPC. Successful biopsy was determined by histologic confirmation of tumor cells and successful isolation of RNA for molecular analysis.The overall success rate of CT-guided bone biopsies was 69% based on histology and 64% based on isolation of molecular material for RNA sequencing. Biopsies performed in lesions with areas of radiolucency had significantly higher diagnostic yields compared with lesions of predominantly dense sclerosis and lesions of predominantly subtle sclerosis. Success rates increased in lesions with density ≤ 475 HU and in lesions with ill-defined margins. Alkaline phosphatase was the only clinical parameter to correlate significantly with diagnostic yield.Image-guided bone tumor biopsies can be successfully used to acquire cellular and molecular material for analyses in patients with osteoblastic prostate cancer metastases. Diagnostic yields are significantly increased in lesions with areas of radiolucency, density ≤ 475 HU, ill-defined margins, and interval growth and in patients with alkaline phosphatase > 110 U/L.