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71.
72.
Electrically controllable all-fiber PMD emulator using a compact array of thin-film microheaters 总被引:2,自引:0,他引:2
Hauer M.C. Yu Q. Lyons E.R. Lin C.H. Au A.A. Lee H.P. Willner A.E. 《Lightwave Technology, Journal of》2004,22(4):1059-1065
An electrically controllable, all-fiber polarization-mode dispersion (PMD) emulator is constructed using thin-film microheaters to temperature tune the birefringence of 30 PM-fiber sections spliced at 45/spl deg/ angles. Compact packaging is achieved by mounting the fiber heaters onto an array of silicon V-grooves. The advantages of this electrically tunable emulator design are low loss, negligible PDL, simple construction, no internal reflections, and no moving parts. 相似文献
73.
The bladder wall penetration kinetics of intravesical doxorubicin were examined in radical cystectomy patients, to provide insight into drug concentrations at target tumor sites. The dosing solution (40 mg/20 ml) was instilled just prior to the start of surgery and maintained for 60-115 min until just prior to bladder excision. The data showed considerable inter-patient variability in the peak plasma concentration (24-fold), urine concentration (7- fold), and tissue concentration (28-fold). The urine concentration at the time of tissue harvest was about 17% of the concentration in the dosing solution. This was due to the dilution by post-catheterization residual urine and urine produced during treatment. The doxorubicin concentration dropped by 32-fold across the urothelium, and declined semi-logarithmically with respect to depth in the capillary-perfused tissues beneath the urothelium with a 50% decrease over about 500 micromole. In three of six patients from whom tumor tissue was obtained, the doxorubicin concentration was higher than the adjacent non-tumor-bearing tissues of comparable tissue depth, whereas the reverse was seen in the remaining three tumors. The plasma concentrations were 0.02, 0.03, 0.05, 0.27, and 0.69% of the concentrations in the tumors, urothelium, lamina propria, superficial and deep muscle layers, respectively. These data indicate: (a) a considerable intra- and inter-patient variability in bladder tissue concentrations, in part due to the variability in the urine concentration; (b) the urothelium is an effective barrier to doxorubicin penetration; and (c) a targeting advantage of intravesical therapy for the treatment of superficial bladder cancer yielding superficial bladder tissue concentrations at least 2000-fold higher than in the systemic circulation. A comparison of the data of doxorubicin with our previously published data on mitomycin C shows similar bladder tissue pharmacokinetics for the two drugs, suggesting that there is no pharmacokinetic preference for either drug. 相似文献
74.
Davis James H.; Hulbert Lorne; Au Wing Tung; Chen Xiao-ping; Zarnoth Paul 《Canadian Metallurgical Quarterly》1997,73(4):703
Six-person mock civil juries awarded significantly larger amounts for damages than did 12-person juries, and individuals preferred even larger average awards. A reversal of the "deep-pockets bias" observed earlier, an explanation involving temporal fluctuation in normative standards, during the time interval between the studies, was supported by independent data showing temporal trends in actual civil trial awards. A computational model of consensus that assumed a strong majority of those members with the most similar (closest) personal preferences decided on the median of their preferences accurately predicted award magnitude. Computer simulations explored the effects of critical faction size (majority, etc.) and location within the group, features that might in turn depend on task environment, cultural dynamics, and social context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Coagulase-negative staphylococcus (C-NS) are regarded as normal flora of the lids and conjunctiva. The ability of these organisms to cause conjunctivitis and blepharitis can be overlooked or disregarded. To elucidate the role of individual C-NS species in these eye diseases we compared Staphylococcus sp. isolated from the conjunctiva and lids of 50 healthy volunteers with 248 strains of Staphylococcus isolated from patients with staphylococcal conjunctivitis or blepharitis. S. epidermidis was the most frequent species isolated from the conjunctiva and lids of both groups. S. aureus was isolated only from infected patients. No individual C-NS species was found to be significantly associated with eye disease, but the colony count of C-NS after isolation was a useful indicator of conjunctivitis and blepharitis. The ability of Staphylococcus to ferment mannitol or mannose was associated with isolates only from infected patients. 相似文献
76.
This paper presents the results of a study on the introduced, free-ranging patas monkey population of Southwestern Puerto Rico (SWPR). It describes information on the population size, social group composition, diet, daily ranging patterns, and patas home range during a 3 year period. The patas monkey population in the study area consisted of approximately 120 individuals in four heterosexual groups and several all-male bands. Within their home ranges (26.8 km2), the population density was 4.47 individuals/km2. Home range size among the population's four heterosexual groups varied from 3.72 km2 to 15.39 km2, and minimum daily distance traveled ranged from 0.8-2.0 km. In general, the social structure and mating system of this population parallels what has been described for African populations. However, habitat use, ranging behavior, and the quality of intergroup interactions suggests that patas of this population exhibit territorial behavior. 相似文献
77.
78.
Application of Strong Fluctuation Random Medium Theory to Scattering from Vegetation-Like Half Space
A model for vegetation scatter is developed using the theory of electromagnetic wave propagation in random medium with strong permittivity fluctuations. In applying the strong fluctuation theory, the singularity of the dyadic Green's function is taken into account. Backscattering coefficients are computed using the distorted Born approximation and illustrated as a function of incidence angle, frequency and moisture content of the vegetation. The mixing formula of the de Loor [28] was used in estimating the permittivity of leaves. The correlation function of Fung and Fung [18], and Fung and Ulaby [19] is used for the random medium. 相似文献
79.
Tsang Leung Blanchard Andrew J. Newton Richard W. Kong Jin Au 《Geoscience and Remote Sensing, IEEE Transactions on》1982,(4):482-485
A simple approximate relation between backscattering coefficient and emissivity measurements is derived. The relation is applicable to active and passive microwave remote sensing of earth terrain where volume scattering plays a dominant role. From the relation, one can obtain a rough estimate of the backscattering coefficient from the emissivity and vice versa. Such estimation is useful in checking experimental measurements and also helps to ascertain the validity of theoretical models. It also safeguards against obtaining arbitrarily high values for both backscattering coefficients and emissivities. 相似文献
80.