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61.
Hypersurface isolated singularities are considered in the context of algebraic analysis. A method for computing relative ?ech cohomology representations of algebraic local cohomology classes supported at the isolated singular point is described. An effective method to test membership and a method to compute the normal form for the Jacobi ideal are presented. The main purpose of this paper is to provide an effective algorithm for computing annihilating ideals, in the ring of partial differential operators, of the algebraic local cohomology class that generates the dual vector space to the local Milnor algebra. 相似文献
62.
Tropospheric aerosol optical properties derived from lidar, sun photometer, and optical particle counter measurements 总被引:1,自引:0,他引:1
Tropospheric aerosols have been observed for the period from November 1990 to April 1992 with a lidar, a sun photometer, and an optical particle counter. Variations of aerosol optical thickness derived from the lidar and the sun photometer data and measurements are presented. The simultaneous measurements of these instruments also allowed us to estimate the extinction-to-backscatter ratio (S(1)), which ranged from 20 to 70. Comparison of optical thicknesses derived from both instruments clearly shows the effect of Mt. Pinatubo's eruption and the temporal variation of optical thickness in the stratosphere over 12 km. The possible range of the complex refractive index for the columnar mean aerosols can be deduced from the probable range of S(1) derived by the use of an S(1) diagram as a function of complex refractive index (m). The imaginary part of m can be estimated provided that the real part of m is known. 相似文献
63.
A challenging task that must be accomplished for every legged robot is creating the walking and running behaviors needed for it to move. In this paper we describe our system for autonomously evolving dynamic gaits on two of Sony's quadruped robots. Our evolutionary algorithm runs on board the robot and uses the robot's sensors to compute the quality of a gait without assistance from the experimenter. First, we show the evolution of a pace and trot gait on the OPEN-R prototype robot. With the fastest gait, the robot moves at over 10 m/min, which is more than forty body-lengths/min. While these first gaits are somewhat sensitive to the robot and environment in which they are evolved, we then show the evolution of robust dynamic gaits, one of which is used on the ERS-110, the first consumer version of AIBO. 相似文献
64.
Kei Ikeda-Murakami Naoto Tani Tomoya Ikeda Yayoi Aoki Takaki Ishikawa 《International journal of molecular sciences》2022,23(3)
Caffeine, a common ingredient in energy drinks, crosses the blood–brain barrier easily, but the kinetics of caffeine across the blood–cerebrospinal fluid barrier (BCSFB) has not been investigated. Therefore, 127 autopsy cases (Group A, 30 patients, stimulant-detected group; and Group B, 97 patients, no stimulant detected group) were examined. In addition, a BCSFB model was constructed using human vascular endothelial cells and human choroid plexus epithelial cells separated by a filter, and the kinetics of caffeine in the BCSFB and the effects of 4-aminopyridine (4-AP), a neuroexcitatory agent, were studied. Caffeine concentrations in right heart blood (Rs) and cerebrospinal fluid (CSF) were compared in the autopsy cases: caffeine concentrations were higher in Rs than CSF in Group A compared to Group B. In the BCSFB model, caffeine and 4-AP were added to the upper layer, and the concentration in the lower layer of choroid plexus epithelial cells was measured. The CSF caffeine concentration was suppressed, depending on the 4-AP concentration. Histomorphological examination suggested that choroid plexus epithelial cells were involved in inhibiting the efflux of caffeine to the CSF. Thus, the simultaneous presence of stimulants and caffeine inhibits caffeine transfer across the BCSFB. 相似文献
65.
H Takamura Y Endo I Ninomiya Y Yonemura T Sasaki 《Canadian Metallurgical Quarterly》1995,53(7):1678-1682
To investigate the interrelationship between integrin VLA3 overexpression and liver metastasis, immunohistochemical studies of VLA3 were made in 73 cases of gastric cancer (66 cases without liver metastasis, 7 cases with liver metastasis) and 15 cases of colorectal cancer (3 cases without liver metastasis, 12 cases with liver metastasis). The rate of integrin VLA3 expression in 69 primary gastric and colorectal cancers without liver metastasis was 41%, that was higher than that (0%) in the 19 primary tumors of gastric and colorectal cancers with liver metastasis. In contrast, the positive rate for integrin VLA3 staining in 19 cases involving liver metastasis of gastric and colorectal cancers was 58% (11/19), which was higher than that (0%) in primary tumors. These findings suggest that VLA3 may play an important role in the process of liver metastasis of gastric and colorectal cancers. 相似文献
66.
The morphological effects of micafungin, a member of a new class of antifungal agents candins, on growing hyphae of Aspergillus fumigatus were studied by the use of Nomarski microscopy, scanning electron microscopy and thin-section electron microscopy. Micafungin at concentrations of 0.001-0.1 microg ml(-1) strongly inhibited the in vitro growth of this fungus and induced striking changes in the hyphal morphology, depending on the drug concentration and the length of the incubation period. The changes observed included increased formation of branches on the lateral walls, disruption of the tips of both hyphal cells and branches, and crushing and collapse of whole hyphae. In addition, micafungin was also effective in damaging membranous structures, including disruption of the cell membrane, partial loss of nuclear membranes and expansion of endoplasmic reticula. From these results, it was concluded that micafungin primarily affected the normal formation of cell walls and septa of growing hyphae. The inhibition of apical growth of hyphae accompanied by excessive lateral branching that was followed by disruption of both hyphal tips and branch tips ultimately led to the destruction of whole hyphae. This cytological effect of micafungin on the hyphal growth of A. fumigatus can explain its potent anti-Aspergillus activity. 相似文献
67.
Paul?Yue Shen-En?ChenEmail author Yayoi?Nishihama 《Journal of Nondestructive Evaluation》2005,24(2):55-66
Ceramic candle filters are stiff cylindrical structures arranged in rosettes in a hot gas vessel. Custom-made with strong
composite materials, these filters are designed to withstand heating and cooling cycles of very high temperature gradients
during coal energy production processes. To ensure consistency in the manufactured filters, noncontact dynamic characterization
using laser vibrometry is proposed as a factory quality control technique. To evaluate the proposed technique, a sensitivity
study using both contact and noncontact vibration measurements is first conducted. The shift in natural vibration frequencies
is used as a quality indicator for likely manufacturing variables. Six candle filters are tested using dynamic impact tests.
Contact and noncontact results are compared with theoretical natural frequency values, which show that laser results were
“noisier” due to dropout from speckle noises. The results are used to establish the sensitivity of the technique, which indicates
that dynamic characterization is a valid nondestructive testing technique for quality assurance of the ceramic filters, provided
that the manufactured filters have a quality variation greater than 3.21%. 相似文献
68.
Yuichi Sato Motoya Kanda Hirokazu Niki Mitsushi Ueno Kenji Murata Tamotsu Shirogami Tsutomu Takamura 《Journal of power sources》1983,9(2):147-159
Because of internal shorting due to zinc (Zn) dendrite formation at the Zn electrode, nickel-zinc (NiZn) secondary cell cycle life is somewhat less than the NiCd cell cycle life. To solve this problem, a new kind of separator was developed which consisted of nylon non-woven cloth coated with poly(vinyl alcohol) (PVA) containing boric acid. This separator has a high ionic conductivity, but is resistant to zincate ion penetration. A large number of additives, effective for Zn dendrite suppression, was also tested. From them, bismuth oxide (Bi2O3) was selected and added, together with calcium hydroxide (Ca(OH)2), to the Zn electrode. A charging method, applying an intermittent anodic pulse, was found to be effective to reduce the Zn electrode shape change and prolong the cycle life of this cell. By using these materials and investigating a cell construction containing an electrolytic solution and hydrogen gas absorber, sizes AA, C, and D sealed NiZn cells were developed whose charging and discharging cycle life achieved over 500 cycles, for a size C cell. 相似文献
69.
"In an attempt to clarify the effects of social isolation on the motivations of the child, the aggressive behavior of 48 children in a 10-minute modified doll play situation was studied in relation to other experimental conditions of isolation and interaction with adult experimenters, order of conditions, sex of child, and sex of experimenter. The major findings were: (a) the children showed a significantly greater frequency of aggressive behavior in doll play preceded by isolation than in doll play preceded by interaction experience; (b) boys were more aggressive than girls." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.