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71.
An unusual case of dislocation of the midfoot through the calcaneocuboid and naviculocuneiform joints is presented. The prognosis is excellent for most midfoot dislocations, as long as they are recognized and treated early.  相似文献   
72.
BACKGROUND: Patients treated for primary hyperparathyroidism run an increased risk of death. The aim of this study was to analyse several factors that may influence their risk of death. METHODS: General, laboratory, physical and clinical variables, altogether 34 variables, were defined as possible risk factors for death and were studied in a patient series of 845 patients operated on during the period 1953-82. Mean follow-up time was 10.5 years (SD 5.9); 253 patients were deceased at follow-up. Cox's proportional hazard model was used. RESULTS: We found seven variables with independent influence on the risk of death: age, sex, diabetes, cardiovascular disease, glomerular filtration rate, renal tubular concentration capacity and amount of diseased parathyroid tissue. The remaining 27 variables were separately tested, one at a time, using the same method and with the influence of age and sex eliminated. In this test situation, the year of surgery, peak serum calcium, serum creatinine level, body mass index, hypertension, psychiatric symptoms and a history of crisis were all significantly related to the risk of death. The analyses also gave information on the direction and magnitude of the effect of the variables on the risk of death. CONCLUSION: Primary hyperparathyroidism itself is a risk factor for death, but it was concluded that well-preserved renal function at surgery seems to have a protective role. We also found that the greater the amount of diseased parathyroid tissue the lesser the renal function and, furthermore, that hyperparathyroidism of substantial degree or long duration may bring about renal impairment that is not necessarily disclosed by the creatinine value alone.  相似文献   
73.
A forward‐propagation learning rule (FPL) has been proposed for a neural network (NN) to learn an inverse model of a controlled object. A feature of FPL is that the trajectory error propagates forward in NN and appropriate values of two learning parameters are required to be set. FPL has only been simulated to several kinds of controlled objects such as a two‐link arm in a horizontal plane. In this work, we applied FPL to AIBO and showed the validity of FPL on a real controlled object. At first, we tested a learning experiment of an inverse dynamic of a two‐link arm in a sagittal plane with viscosity and Coulomb friction by computer simulation. In this simulation, a low‐pass filter (LPF) was applied to realized trajectories because coulomb friction vibrates them. From the simulation results, we found that the learning process is stable by some adequate sets of the learning parameters although it is more sensitive to the values of the parameters owing to friction and gravity terms. Finally, we tested applying FPL to motor control of AIBO's leg. The inverse dynamics model was acquired by FPL with only about 150 learning iterations. From these results, the validity of the FPL was confirmed by the real robot control experiments. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(4): 38–48, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20456  相似文献   
74.
MgB2 superconducting wires were produced by the Mg diffusion method. Scanning electron microscopy (SEM), optical microscopy, dispersive X-ray analysis (EDS), and XRD diffraction were used to study the physical structure and content of the wires. Magnetic properties (T c m, H c1, H c2, J c by the Bean model) were obtained with a SQUID magnetometer, and transport properties (T c r , H c2, resistivity and residual resistivity ratio) were measured using a standard four-lead configuration. The V-I characteristics of the wires close to the critical temperature showed a staircase response, which was attributed to the presence of weak links, creating phase slip centers. The origin of those weak links is discussed in relation to their formation and structure.  相似文献   
75.
The dielectric properties of ceramics pressurelessly sintered from nano (10-100 nm) and fine (0.8-1.0 μm) aluminum nitride powders have been studied. High-purity aluminum nitride sintered from nanopowder of nearly-theoretical density has been found to exhibit a low dielectric constant ε = 6.3 and low loss, tgδ = 0.011 at 3.32 GHz. Ceramics sintered from a fine aluminum nitride powder doped with yttrium oxide have revealed ε = 7.7 and tgδ = 0.021 at 3.23 GHz. The dielectric properties have allowed us to use ceramics sintered from fine aluminum nitride powder as a material for microwave windows for the diagnosis and treatment of tumors of the larynx and breast.  相似文献   
76.
77.
People regulate their affect either to feel good or to achieve instrumental success. The present experiments show that when driven by performance goals, people can be motivated to experience unpleasant affect when it is trait-consistent, because of its instrumental benefits (e.g., M. Tamir & M. D. Robinson, 2004). In 4 studies, individuals high in neuroticism were more likely than those low in neuroticism to choose to increase their level of worry, as indicated by self-reported preferences (Study 1) and by behavioral choices in experimental settings (Studies 2-4). As predicted, such preferences were evident when expecting to perform demanding tasks but not when expecting an undemanding task (Study 2). Study 4 suggests that such preferences for short-term unpleasant affect may be beneficial to performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
This paper addresses the issue of fault estimation and accommodation for a discrete‐time switched system with actuator faults. Here, we assume that the sojourn probabilities are known a priori. By using the reduced‐order observer method, the sojourn probability approach, and the Lyapunov technique, a fault estimation algorithm is obtained for the considered system. The main objective of this work is to design a dynamic output feedback fault‐tolerant controller based on the obtained fault estimation information such that the closed‐loop discrete‐time switched system with available sojourn probabilities is robustly mean‐square stable and satisfies a prescribed mixed and passivity disturbance attenuation level in the presence of actuator faults. More precisely, a dynamic output feedback fault‐tolerant controller is established in terms of linear matrix inequalities. Finally, numerical examples are provided to illustrate the usefulness and effectiveness of the proposed design technique.  相似文献   
79.
In this paper, the authors investigated the reflection and absorption characteristics of a general photovoltaic (PV) module. As a result, the electromagnetic waves could be attenuated only 6 dB in typical PV module. However, if the PV module is installed in the outer wall of buildings, electromagnetic interference is caused by the surroundings. To reduce this electromagnetic interference, the authors suggested a method to absorb electromagnetic wave using multiple PV modules that have deference impedance, and simulation was performed. As a result, it was confirmed that using a typical PV module and the PV module including electronic device, the reflection waves of those PV modules could be attenuated up to 12 dB.  相似文献   
80.
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