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151.
Muscle wasting, known to develop in patients with chronic kidney disease (CKD), is a deleterious consequence of numerous complications associated with deteriorated renal function. Muscle wasting in CKD mainly involves dysregulated muscle protein metabolism and impaired muscle cell regeneration. In this narrative review, we discuss the cardinal role of the insulin-like growth factor 1 and myostatin signaling pathways, which have been extensively investigated using animal and human studies, as well as the emerging concepts in microRNA- and gut microbiota-mediated regulation of muscle mass and myogenesis. To ameliorate muscle loss, therapeutic strategies, including nutritional support, exercise programs, pharmacological interventions, and physical modalities, are being increasingly developed based on advances in understanding its underlying pathophysiology.  相似文献   
152.
Depositing gate metal across a step undercut between the Schottky barrier layer and the insulator-like layer is employed to obtain a reduced gate length of 0.4 mum with an additional 0.6-mum field plate from a 1-mum gate window. Most dc and ac characteristics including current density (IDSS=451mA/mm), transconductance (gm,max=225mS/mm), breakdown voltages (VBD(DS)/V BD(GD)=22/-25.5V), gate-voltage swing (GVS=2.24V), cutoff, and maximum oscillation frequencies (ft/fmax=17.2/32GHz) are improved as compared to those of a 1-mum gate device without field plate. At a VDS of 4.0 V, a maximum power added efficiency of 36% with an output power of 13.9 dBm and a power gain of 8.7 dB are obtained at a frequency of 1.8 GHz. The saturated output power and the linear power gain are 316 mW/mm and 13 dB, respectively  相似文献   
153.
Globalization has inevitably forced firms to pursue outsourcing as a strategy to reduce operating costs and improve their competitiveness in the global marketplace. However, a successful outsourcing activity depends on the selection of the appropriate provider. Unlike previous multiple criteria decision-making (MCDM) methods that assume the criteria are independent, we propose a novel hybrid model, combining a Decision Making Trial and Evaluation Laboratory (DEMATEL) and Analytical Network Process (ANP) method called DANP, which addresses the dependent relationships between the various criteria to better reflect the real-world situation. At the same time, instead of ranking the alternatives, we apply a modified grey relation method to select and improve the criterion-gaps to the aspiration levels. To demonstrate the usefulness and effectiveness of the proposed model, we use data from a Taiwanese company.  相似文献   
154.
We extended the application of Roger's model for evaluating the institutional forces influencing the adoption intention of RFID by retailer's suppliers. Drawing on institutional theory, we examined how different institutional forces experienced by retailer's suppliers were related to their relational investment on inter-organizational information sharing. Data collected from 130 major Taiwanese suppliers was used in our empirical analyses. We found that relational investment was the most critical adoption factor, which also indirectly enhanced organizational readiness for technological adoption intention. From a Taiwanese perspective, our findings should be helpful in understanding what factors significantly impact the adoption of RFID technology.  相似文献   
155.
156.
In the present paper, two major analyses are achieved. In the first, experimental procedures were accomplished to measure tensile mechanical properties of copper (Cu) wire (= 1 mil) before/after electric flame-off (EFO). Characteristics of free air ball (FAB), heat affected zone (HAZ) and thermal stable zone (TSZ) in as-drawn wire have been carefully investigated by microhardness, self-design pull test fixture, nanoindentation and atomic force microscopy (AFM). A 2nd EFO real-time technique has been conducted to reduce the strength of Cu wire and increase the bonding region. Secondary, with the obtained experimental material data, a comprehensive finite element wirebonding model based on explicit time integration software ANSYS/LS-DYNA is developed to predict the overall strain/stress distributions on the aluminum (Al) bond pad. Finite element analysis (FEA) results demonstrate that plastic deformation on Al bond pad around smashed FAB can be reduced by increasing the surface roughness on FAB. A series of comprehensive parametric studies were conducted in this research.  相似文献   
157.
A novel method to improve the cycling capacity degradation of Mg2Ni-based hydrogen storage alloy by means of composite materials has been proposed. The new composites Mg2Ni-x mol% Mg3AlNi2 (x = 0, 15, 30, 60, 100) were prepared by means of combining electric resistance melting with isothermal evaporation casting process (IECP). Phase analysis and microstructure were investigated by SEM and TEM observations. Results showed that the cycling stability of the alloy with Mg3AlNi2 was superior to that of Mg2Ni. XPS analysis revealed that the formation of an Al oxide film during cycling could enhance the anti-corrosion of the surface of the composites. Among the obtained capacity retaining rates, Mg2Ni-15 mol% Mg3AlNi2 composite had the best anti-corrosion performance. This composite has kept 76% of its maximum discharge capacity (50 mA hg?1) at 25th cycle compared to 20% for Mg2Ni. The enhancement of the cycling stability of the electrode alloy with 15 mol% Mg3AlNi2 can be ascribed to the decrease in the rate of pulverization of the alloy during cycling, which is considered as the factor in the improvement of the electrochemical properties of the Mg3AlNi2-containing alloys.  相似文献   
158.
We show how we use the Deforming-Spatial-Domain/Stabilized Space–Time (DSD/SST) formulation for accurate 3D computation of the aerodynamics of a wind-turbine rotor. As the test case, we use the NREL 5MW offshore baseline wind-turbine rotor. This class of computational problems are rather challenging, because they involve large Reynolds numbers and rotating turbulent flows, and computing the correct torque requires an accurate and meticulous numerical approach. We compute the problem with both the original version of the DSD/SST formulation and a recently introduced version with an advanced turbulence model. The DSD/SST formulation with the advanced turbulence model is a space–time version of the residual-based variational multiscale method. We compare our results to those reported recently, which were obtained with the residual-based variational multiscale Arbitrary Lagrangian–Eulerian method using NURBS for spatial discretization and which we take as the reference solution. While the original DSD/SST formulation yields torque values not far from the reference solution, the DSD/SST formulation with the variational multiscale turbulence model yields torque values very close to the reference solution.  相似文献   
159.
Obtaining reliable estimates of the statistical properties of complex macromolecules by computer simulation is a task that requires high computational effort as well as the development of highly efficient simulation algorithms. We present here an algorithm combining local moves, the pivot algorithm, and an adjustable simulation lattice box for simulating dilute systems of bottle-brush polymers with a flexible backbone and flexible side chains under good solvent conditions. Applying this algorithm to the bond fluctuation model, very precise estimates of the mean square end-to-end distances and gyration radii of the backbone and side chains are obtained, and the conformational properties of such a complex macromolecule are studied. Varying the backbone length (from Nb=67 to Nb=1027), side chain length (from N=0 to N=24 or 48), the scaling predictions for the backbone behavior as well as the side chain behavior are checked. We are also able to give a direct comparison of the structure factor between experimental data and the simulation results.  相似文献   
160.
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