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51.
Two patients with diabetes mellitus sustained spontaneous calcaneus fracture after deep heel burns. Both cases had avulsion type fracture of the os calcis. The authors discuss the incidence and possible etiology with literature review.  相似文献   
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We solve Eliashberg equations in the case of strong anisotropic electron-phonon coupling and low energy cutoff. In a simplified model representing the Fermi Surface of (CuO2)n planes, we exhibit ad-wave solution as well as a generalizeds-wave one.  相似文献   
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Calcium release from the sarcoplasmic reticulum (SR) depending on depolarization of the transverse tubular membrane (TTM) caused by rapid ionic replacement was measured in skeletal muscle triadic vesicles using a stopped-flow apparatus and Fura-2, a membrane-impermeable Ca2+ indicator. Calcium release was triggered by an increase in the magnitude of depolarization. This Ca2+ release was inhibited by ruthenium red, digoxin and dantrolene, and enhanced by caffeine. Thus, Ca2+ release was found to occur through the SR Ca2+ release channel via TTM depolarization and to be able to cause skeletal muscle contraction. Calcium release curves could be divided into two phases. In contrast to other previous studies, in the fast phase the amount of released Ca2+ increased with an increase in the magnitude of depolarization but the Ca2+ release rate did not; on the other hand, in the slow phase the Ca2+ release rate increased but the amount of Ca2+ did not. Furthermore, the Ca2+ release rate was controlled by the luminal Ca2+ concentration of the SR only in the fast phase. These independent dual kinetics of Ca2+ release were explained by the calsequestrin regulation model.  相似文献   
55.
This case report describes a localized interproximal soft-tissue lesion in the anterior maxillary area that may have been caused by a composite curing light. Following clinical examination and histological analysis, the diagnosis of acute osteomyelitis was made. Palliative treatment and debridement resulted in complete resolution.  相似文献   
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The Frascati tokamak upgrade Thomson-scattering system is used for the measurement of electron-temperature and electron-density spatial profiles along the vertical diameter of the tokamak at 19 spatial points up to 10 times in a single plasma discharge, with a spatial resolution that ranges from 2 cm in the central region to 4 cm in the plasma edge. The radiation source is a Nd:YLF laser that operates at 1053 nm, with a divergence of 0.4 mrad full angle, and is capable of delivering a burst of 10 pulses with energies of 4.5 J/pulse; the interpulse time can be regulated from 20 to 100 ms. The scattered radiation is collected by two objectives: the first looks at the plasma center, and the second at the plasma edge. Bundles of optical fibers in the focal plane of the objectives carry the scattered light from the tokamak hall to a set of 19 interference-filter polychromators, whose transmission is 70%, and the rejection of the stray light at the laser wavelength is 1/10(7). The detectors are avalanche photodiodes ith a noise-equivalent power of the order of 10(-13) W/(Hz)(?) at 1053 nm. The spectral calibration of the polychromators is presented. The absolute calibration of the scattering system for the electron-density measurement has been carried out by the use of Raman scattering on hydrogen and deuterium. Examples of the results of the temporal evolution of T(e) and n(e) spatial profiles are presented for ohmic plasma heating, lower-hybrid current drive, and a pellet-injection experiment. The electron-temperature and electron-density profiles measured through Thomson scattering are compared with the temperatures measured through the use of electron-cyclotron emission and the density profiles obtained from the interferometer data.  相似文献   
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Wireless Personal Communications - The present work explores the scope of cognitive radio networks (CRNs) to support the spectrum demand on future diverse application specific wireless services...  相似文献   
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Ghosh  Sutanu  Acharya  Tamaghna  Maity  Santi P. 《Wireless Networks》2019,25(7):3867-3881

This paper explores an end-to-end outage probability experienced in a bidirectional relay assisted communication where the relay is assumed to be equipped with an RF energy harvesting circuit. First, the closed-form expression for the outage of the system is derived. This is followed by the formulation of an unconstrained optimization problem to achieve minimum outage probability with respect to the relay placement and consequent time allocation for energy harvesting. The system model is further extended in an underlay cognitive radio framework to study the impact of a primary user outage constraint on the end-to-end outage performance of the two-way communications. The accuracy of analytical results is validated through simulation results. The impact of various system parameters like relay position, time allocation factor, target rate of transmission on the outage probability is also observed. In addition, it is also shown that spectral efficiency of the communication system using hybrid power-time switching relaying protocol is much superior to similar one-way and two-way relay assisted communication system with power splitting relaying protocol.

  相似文献   
60.
The microstructural evolution, non‐Ohmic properties, and giant dielectric properties of CaCu3Ti4?xGexO12 ceramics (x=0‐0.10) are systematically investigated. The Rietveld refinement confirms the existence of a pure CaCu3Ti4O12 phase in all samples. Significantly enlarged grain sizes of CaCu3Ti4?xGexO12 ceramics are associated with the liquid phase sintering mechanism. Enhanced dielectric permittivity from 6.90×104 to 1.08×105 can be achieved by increasing Ge4+ dopant from x=0‐0.10, whereas the loss tangent is remarkably reduced by a factor of ≈10. NonOhmic properties are enhanced by Ge4+ doping ions. Using impedance and admittance spectroscopies, the underlying mechanisms for the dielectric and nonlinear properties are well described. The improved nonlinear properties and reduced loss tangent are attributed to the enhanced resistance and conduction activation energy of the grain boundaries. The largely enhanced permittivity is closely associated with the enlarged grain sizes and the increase in the Cu+/Cu2+ and Ti3+/Ti4+ ratios, which are calculated from the X‐ray absorption near‐edge structure.  相似文献   
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