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81.
The author examined macroscopic behavioral patterns in a crowd of pedestrians in a large crosswalk from the perspective of micro–macro linkage in collective behavior. Study 1 developed a macrolevel index to evaluate by field observation a "banded structure" of a pedestrian crowd. The index distinguished 2 patterns of crowd behavior: one with a firmly established structure and one without a clear structure. To examine the formation of the structure, Study 2 used a computer simulation model of pedestrian behavior with a close relationship between the microlevel behavior of individuals and macrolevel behavior of crowds. The micro-macro linkage is expressed through feeding the macrolevel index developed in Study 1 back into a behavioral model for each pedestrian. The results show that models without the linkage between the 2 levels tend to simulate disorganized crowd behavior. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
82.
Metallurgical and Materials Transactions B - Normal spectral emissivity of molten Cu-Fe alloy with different compositions was measured at the wavelength of 807 nm using an electromagnetic...  相似文献   
83.
We consider the effects of spin-phonon coupling within the slave-boson mean-field treatment of the extended t-J model. With no additional assumptions the theory is found to give a semi-quantitative account of the frequency and linewidth anomalies observed for certain phonon modes in Y Ba2Cu3O7 at the superconducting transition. We report also investigations of the role of this coupling in affecting thermodynamic properties and spin dynamics.  相似文献   
84.
In this report, we introduce a new entry of high-performance polymer-based monolithic capillary column for mainly small molecules. This capillary column was prepared using a newly introduced epoxy monomer with diamines. Simply heat-induced polycondensation in an appropriate porogenic solvent afforded a really homogeneous co-continuous monolithic structure having submicrometer-size skeletons with micrometer-size through-pores. We were also able to prepare chiral monolithic columns using a chiral epoxy monomer as well as a chiral diamine. A 21.5-cm-long, 100-mum-i.d. column afforded up to 40 000 theoretical plate numbers (N) for alkylbenzenes in 60% aqueous acetonitrile as a reversed-phase-mode stationary phase. Due to a quite low column pressure drop, a 150-cm-long column was prepared. This long column afforded up to 200 000 plates for alkylbenzenes with only a 4-MPa column pressure drop. In contrast, in 100% acetonitrile, this column has "HILIC" property to show up to 60 000 plates for methanol with a 17.5-cm-long column. In this mode, we were able to separate nucleic acids. In addition, we have prepared a chiral column with both of the chiral epoxy monomers and an amine. This column was able to chirally discriminate a racemic alcohol in a reversed-phase mode.  相似文献   
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The plasma pharmacokinetics of danofloxacin administered at 1.25 mg kg-1 body weight by the intravenous and intramuscular routes were determined in sheep. Tissue distribution was also determined following administration by the intramuscular route at 1.25 mg kg-1 body weight. Danofloxacin had a large volume of distribution at steady state (Vdss) of 2.76 +/- 0.16 h (mean +/- S.E.M.) L kg-1, an elimination half-life (t1/2 beta) of 3.35 +/- 0.23 h, and a body clearance (C1) of 0.63 +/- 0.04 L kg-1 h-1. Following intramuscular administration it achieved a maximum concentration (Cmax) of 0.32 +/- 0.02 microgram mL-1 at 1.23 +/- 0.34 h (tmax) and had a mean residence time (MRT) of 5.45 +/- 0.19 h. Danofloxacin had an absolute bioavailability (F) of 95.71 +/- 4.41% and a mean absorption time (MAT) of 0.81 +/- 0.20 h following intramuscular administration. Mean plasma concentrations of > 0.06 microgram mL-1 were maintained for more than 8 h following intravenous and intramuscular administration. Following intramuscular administration highest concentrations were measured in plasma (0.43 +/- 0.04 microgram mL-1), lung (1.51 +/- 0.18 micrograms g-1), and interdigital skin (0.64 +/- 0.18 microgram g-1) at 1 h, duodenal contents (0.81 +/- 0.40 microgram mL-1), lymph nodes (4.61 +/- 0.35 micrograms g-1), and brain (0.06 +/- 0.00 microgram mL-1) at 2 h, jejunal (10.50 +/- 4.31 micrograms mL-1) and ileal (5.25 +/- 1.67 micrograms mL-1) contents at 4 h, and colonic contents (8.94 +/- 0.65 micrograms mL-1) at 8 h.  相似文献   
88.
Studies in vitro suggested that inflammatory cytokines could cause myocardial dysfunction. However, the detailed mechanism for the cytokine-induced myocardial dysfunction in vivo remains to be examined. We thus examined this point in our new canine model in vivo, in which microspheres with and without IL-1beta were injected into the left main coronary artery. Left ventricular ejection fraction (LVEF) was evaluated by echocardiography for 1 wk. Immediately after the microsphere injection, LVEF decreased to approximately 30% in both groups. While LVEF rapidly normalized in 2 d in the control group, it was markedly impaired in the IL-1beta group even at day 7. Pretreatment with dexamethasone or with aminoguanidine, an inhibitor of inducible nitric oxide synthase, prevented the IL-1beta-induced myocardial dysfunction. Nitrotyrosine concentration, an in vivo marker of the peroxynitrite production by nitric oxide and superoxide anion, was significantly higher in the myocardium of the IL-1beta group than in that of the control group or the group cotreated with dexamethasone or aminoguanidine. There was an inverse linear relationship between myocardial nitrotyrosine concentrations and LVEF. These results indicate that IL-1beta induces sustained myocardial dysfunction in vivo and that nitric oxide produced by inducible nitric oxide synthase and the resultant formation of peroxynitrite are substantially involved in the pathogenesis of the cytokine-induced sustained myocardial dysfunction in vivo.  相似文献   
89.
OBJECTIVE: To determine the distribution and significance of microcalcifications in histologic sections of the prostate. DESIGN: Retrospective review of all histologic slides of completely embedded prostates from surgical specimens. MATERIALS: Randomly selected material included 266 radical prostatectomy and 10 cystoprostatectomy prostates without prostate cancer. Nonrandomly selected specimens included 26 radical prostatectomy specimens with a Gleason pattern 5 component, 24 cases with collagenous micronodules, and 8 cases previously noted to have microcalcifications within foci of prostate cancer. RESULTS: Four patterns of microcalcifications were noted in association with prostate cancer: (1) dystrophic calcification in the comedo-type necrosis of Gleason pattern 5, (2) intraluminal calcification in cribriform-type Gleason pattern 3 prostate cancer, (3) intraluminal calcification in small acinar adenocarcinoma, and (4) stromal calcification within collagenous micronodules associated with prostate cancer. Microcalcifications were noted in 32% of prostates without cancer; 1.9% of randomly selected prostates demonstrated microcalcifications associated with prostate cancer. CONCLUSIONS: Microcalcifications are less common in association with prostate cancer than with benign prostatic ducts and acini. However, intraluminal microcalcifications associated with an atypical small glandular proliferation should not be taken as unequivocal evidence of a benign process.  相似文献   
90.
The wavelength and composition dependencies of normal spectral emissivities for liquid Ag-Cu alloys have been measured over a wavelength range between 450 and 1500 nm at temperatures from 1273 to 1423 K in a cold crucible furnace. The spectral emissivities abruptly increase in the visible region with decreasing wavelength. The wavelength at the abrupt increase in the emissivity shifts to a shorter wavelength as the concentration of silver in the alloy increases. This suggests that the abrupt increases are attributed to the direct interband transition, and the energy gap between the d band and the Fermi level increases with an increase in silver concentration in the alloy. To the contrary, the spectral emissivities in the infrared region were found to exhibit weak negative wavelength dependencies, which are attributed to the intraband transition. The composition dependencies of spectral emissivities observed in the infrared region have been explained by the Drude model.  相似文献   
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