A thermomechanical fracture modeling and simulation for functionally graded solids using a residual-strain formulation

This paper addresses mixed-mode crack growth in two-dimensional functionally graded solids under thermomechanical loads, and investigates the effect of mechanical and thermal loads as well as the T-stress on their crack growth behavior. A novel residual strain-based formulation in the interaction integral method is developed and used for the accurate evaluation of mixed-mode stress intensity factors and/or the T-stress. Simulation of mixed-mode crack propagation in functionally graded materials including solid oxide fuel cells under thermomechanical loads is performed by means of the finite element method and the generalized interaction integrals in conjunction with a remeshing algorithm. An iterative procedure is used for crack growth simulation including the calculation of mixed-mode stress intensity factors and/or the T-stress by means of the generalized interaction integral method, determination of crack growth direction and crack initiation condition based on selected fracture criteria, and local automatic remeshing along the crack path. The present approach employs a user-defined crack increment at the beginning of the simulation. Crack trajectories and fracture parameters obtained by the present simulation for thermomechanical loads are assessed for some numerical examples in comparison with those for mechanical loads.     

Putative role of dihydropyrimidine dehydrogenase in the toxic side effect of 5-fluorouracil in colorectal cancer patients

Dihydropyrimidine dehydrogenase (DPD) is the first and rate limiting enzyme in the catabolism of 5-fluorouracil (5-FU). It has been reported from various laboratories that the plasma concentration of 5-FU was influenced by DPD activities in various normal human organs (e.g. liver or lymphocytes). Since the congenital deficiency in DPD caused severe, in some cases lethal, FU-related toxicity, it was decided to collect data about the DPD activity in colorectal cancer patients in order to investigate the possible correlation between the enzyme activity and appearance of the side effects of 5-FU. Assuming that DPD activity in lymphocytes represents the 5-FU catabolic capacity of the organism, DPD activity was determined in the lymphocytes of 48 patients with colorectal cancer after surgery during the therapeutic course with 5-FU and folinic acid. On the basis of the enzyme activity, patients were divided into three categories: low (DPD <5.03 pmol/min/10(6) lymphocytes); medium (DPD = 5.04-13.25 pmol/min/10(6) lymphocytes), and high (DPD > 13.26 pmol/min/10(6) lymphocytes) activity groups. By evaluating the toxic side effects during the 5-FU + folinic acid treatment, the following results were obtained. In the low DPD activity group, 9 of 11 patients had 5-FU-related side effects (mucositis, diarrhea, myelotoxicity, angina pectoris, hypertension). In 3 patients, no change of the therapy was needed, in 3 patients symptoms could be reversed by dose reduction of 5-FU while in 3 patients interruption of 5-FU therapy was needed. In the medium DPD activity group, mild toxicity (diarrhea, transitory hypertension) occurred in 5 of 29 and in the high activity group (diarrhea) in 1 of 8 patients, respectively. In these last two groups, no dose reduction of 5-FU was necessary. The present study furnished further evidence for the possible correlation between the 5-FU side effects and DPD function. Consequently, it is recommended to measure DPD activity prior to 5-FU based chemotherapy, which might be helpful in avoiding drug-related toxicity by adjusting the dose of 5-FU individually.     

Techniques,challenges and future prospects for cell-based meat

Food Science and Biotechnology - In response to a growing population and rising food demand, the food industry has come up with a wide array of alterations, innovations, and possibilities for...     

Experimental and Numerical Investigation of the Deformation and Fracture Mode of Microcantilever Beams Made of Cr(Re)/Al2O3 Metal–Matrix Composite

Metallurgical and Materials Transactions A - This work presents a combined experimental and computational study of the deformation and fracture of microcantilever specimens made of...     

膳食、肠道微生物与人体健康

膳食与宿主的代谢、免疫系统密切相关。大量报道表明膳食显著影响肠道菌群的组成和功能,进一步影响宿主生理。基于肠道菌群膳食干预的健康调控策略已成为研究热点。本文作者综述了近年来国内外高水平团队的相关研究成果,介绍了膳食模式、膳食成分、功能膳食补充剂对肠道微生物及人体健康研究的相互关系,为相关膳食干预策略的开发提供一些借鉴和参考。     

Big Cloud Innovation for Sustainable Wireless Management

Wireless Personal Communications -     

A Novel Method to Detect and Prevent SQLIA Using Ontology to Cloud Web Security

Wireless Personal Communications - Many modern day web applications deal with huge amount of secured and high impact data. As a result security plays a major role in web application development....     

Dissolution,Solubility, XRD,and DSC Studies on Flurbiprofen-Nicotinamide Solid Dispersions

Flurbiprofen-nicotinamide solid dispersions were prepared by the fusion method. The solid dispersions were evaluated for dissolution rate. The drug-carrier interaction in the liquid and solid states were studied by using phase solubility analysis, phase diagram, X-ray diffraction (XRD), and differential scanning calorimentry (DSC). Solid dispersions gave fast and rapid dissolution of flurbiprofen compared with the pure drug and the physical mixture. Phase diagram and DSC indicated that flurbiprofen and nicotinamide form a eutectic mixture. The aqueous solubility of flurbiprofen was enhanced in the presence of nicotinamide.     

Incidence of chromosomal abnormalities in 153 pregnancies with ultrasound detected fetal abnormalities

We report a caroticocavernous fistula (CCF) treated by an endovascular procedure in a young woman with Ehlers-Danlos syndrome type IV, with severe bilateral carotid and vertebral artery dysplasia. The CCF, which appeared after minor trauma, was successfully occluded by a detachable balloon introduced into the venous side by an arterial approach. Six previously published cases are reviewed, five successfully treated. The difficulties and risks of the endovascular procedure due to the vascular changes, are emphasised. The possibility of the venous approach is discussed.