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1.
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies.  相似文献   
2.
We present simulation results of the vortex dynamics in a trapped Bose-Einstein condensate in the presence of a rotating optical lattice. Changing the potential amplitude and the relative rotation frequency between the condensate and the optical lattice, we find a rich variety of dynamical phases of vortices. In particular, when the optical lattice rotates faster than the condensate, the competition between the pinning force and the interactions by nucleated interstitial vortices leads to the melting of vortex lattice, yielding a vortex liquid phase.  相似文献   
3.
A focus on the importance of leisure in the development of student nurses has been neglected in the 1990s. This study considers 444 prospective nurses on conventional, diploma and degree courses in two areas of England. It examines their activities associated with socializing, their social support networks and their use of clubs, sports and hobbies before entering nursing. It is evident that students enter nurse training with a wide variety of leisure experiences. Changing recruitment patterns and the structure of nurse training has an effect on the leisure needs of prospective nurses which must be addressed.  相似文献   
4.
A strontium tantalum sulfide, SrTa2S5, has a hexagonal structure with lattice constants of a =3.32 and c=24.1 Å. With decreasing temperature the electrical resistivity decreases monotonically and exhibits an abrupt superconducting transition at 3.16 K (midpoint). The diamagnetic susceptibility is observed below Tc. The magnetic susceptibility is nearly independent of temperature above Tc and shows Pauli paramagnetism.  相似文献   
5.
Kikuchi  Kenichi 《Behaviormetrika》1996,23(2):187-203

When we select No students from N applicants on the basis of a composite score of subtests, it is important to evaluate the contribution of each subtest. The swap-rate, which is defined as the proportion of the applicants who actually pass the examination but would fail if the j-th subtest were not included in the component to rank the applicants, is one of the measures of the contribution of the j-th subtest.

In this article, first, we derive the characteristics and limiting properties of the population swap-rate. Next, using the properties of the order statistics and the extended hypergeometric distribution, we derive an approximation to the asymptotic variance of the sample swap-rate when the number of applicants is large. Finally, we propose the use of our analytic approximation to the variance of the sample swap-rate in the real data problem and show that it is very efficient.

  相似文献   
6.
A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at PRF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at PRF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window.  相似文献   
7.
With the advancement of high‐frequency switching devices, electromagnetic interferences (EMI) have become problems in power electronic converter designs. It is necessary for an electromagnetic compatibility (EMC) design to prospect and consider its possible EMI levels. This paper describes how to compute effects from a power converter to an object point to reduce conduction EMI noises effectively by an appropriate design. Modeling techniques for converter elements are discussed for a model in the conduction emission frequency band by the parameter tuning method and for line constants by an analytical derivation. Then a derived model is simulated for harmonic distributions of loop currents and their magnetic fields. © 2002 Scripta Technica, Electr Eng Jpn, 139(1): 44–50, 2002: DOI 10.1002/eej.1145  相似文献   
8.
9.
The EGS4 code, developed at Stanford Linear Accelerator Center, simulates electron-photon cascading phenomena. The original code is inherently sequential: processing one particle at a time. This paper reports on a series of experiments in parallelizing different versions of EGS4. Our parallel experiments were run on a 30-processor Sequent Balance B21 and a 6-processor Symmetry S27. We have considered the following approaches for parallel execution of this application code:
1. (1) Original sequential version modified for parallel processing: 1 processor;
2. (2) Version 1 run multiprocessed: 1 to 29 processors;
3. (3) Sequential version modified for large-grain parallel processing: 1 procssor;
4. (4) Version 3 run using the Sequent Microtasking Library: 1 to 29 processors.

For each approach, we discuss the relative advantages and disadvantages in the areas of coding effort, understandability and portability, as well as performance, and outline a new parallelization approach we are currently pursuing based on Large-Grain Data Flow techniques.  相似文献   

10.
In recent years the requirement for the reduction of energy consumption has been increasing to solve the problems of global warming and the shortage of petroleum resources. For example, in the power generation field, as thermal power generation occupied 60% of the power generation demand, considerable improvement of the thermal efficiency is required. This paper describes the pressure drop characteristics of finned tube banks used for heat exchangers in thermal power generation that were clarified by testing serrated finned tube banks with different fin heights for improved heat transfer and conventional spiral finned tube banks with different fin heights, and an equation to predict pressure drop which is necessary for the heat exchanger design is proposed. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(3): 179–193, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20112  相似文献   
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