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81.
82.
It is believed that mammalian chemosensory irritants are not aversive to birds and vice versa. Nevertheless, few avian repellents have been tested against mammals. For that reason, we evaluated the efficacy of 1.0% w/v methyl anthranilate, orthoaminoacetophenone, 2-amino-4,5-methoxyacetophenone, 2-methoxyacetophenone, and veratryl amine as mouse repellents in 3-hr no-choice drinking tests. Relative to ingestion of plain water, all test substances significantly reduced (P < 0.05) intake. Orthoaminoaceto-phenone was the most effective repellent, with intake reduced to levels statistically indistinguishable from zero. 相似文献
83.
Strategic sensemaking and organizational performance: linkages among scanning, interpretation, action, and outcomes. 总被引:2,自引:0,他引:2
This study investigated the strategic "sensemaking" processes of scanning, interpretation, and action and how those activities are linked to organizational performance. Using path analyses on data from 156 hospitals, we tested the direct and indirect effects among these sensemaking processes and performance outcomes and developed a model of their relationships. In a more general sense, the research represents an attempt to provide insight not only into relationships between cognition and action, but also into the links between those fundamental processes and organizational performance outcomes. 相似文献
84.
85.
The far infrared (30–110 cm?1) emission spectrum of the lower stratosphere has been measured from balloon altitudes with a high resolution (0.06 cm?1) rapid-scanning Michelson interferometer on two flights in 1976. The quality and resolution of the spectra obtained from two altitudes have permitted a careful search for emission lines from environmentally important molecules such as HCl, NO2, OH, H2O2, and CO, among the more prominent and well-known features due to H2O, O3 and O2. Column densities have been determined for H2O and O3 and upper limit estimates have been made from tentative identifications of several other constituents. However, the large angular field of view observed by the instrument prevented the determination of concentration profiles from atmospheric limb scans to the horizon. The possible future directions of this technique are outlined on the basis of operating experience over a 6 year programme. The viability of this method of monitoring the concentrations of minor constituents in the stratosphere is discussed with respect to other equivalent techniques. 相似文献
86.
Michael E. Sigman Mary R. Williams Joseph A. Castelbuono Joseph G. Colca C. Douglas Clark 《仪器科学与技术》2013,41(4):375-393
Abstract The mass spectra calculated by summing the intensities of each nominal mass over all chromatographic times, the summed ion spectra, were calculated for a set of 440 commercially available ignitable liquids that had been analyzed by gas chromatography–mass spectrometry. Each ignitable liquid is generally comprised of a mixture of chemicals, and the mixtures may be very complex in some cases, e.g., petroleum distillates, gasoline, etc. The summed ion spectra were evaluated to determine if they contained sufficient information content to allow their use for rapid and accurate identification of the ignitable liquid in a database or library. The summed ion nominal mass spectra were encoded in one bit per channel at 1% transition intensity and a set of 96,580 unique pairwise comparisons were made between spectra, resulting in an average of approximately 50 differing channels per comparison. A subset of 62 summed ion spectra were further compared by a similarity metric and found by cluster analysis to group closely along the ASTM ignitable liquid classification scheme. Receiver operator characteristic analysis of the use of the similarity index in combination with the summed ion spectra was shown to provide 99% probability of correct liquid identification and 95% probability of correct ASTM classification by primary and sub-class. Interlaboratory tests found 95% probability of correct liquid identification and 85% probability of correct ASTM classification at the primary class level. These results demonstrate the use of the summed ion spectrum as a first step in the rapid identification of an ignitable liquid by database or library searching. 相似文献
87.
A method has been developed whereby a fraction of rat brain mitochondria (synaptic mitochondria) was isolated from synaptosomes. This brain mitochondrial fraction was compared with the fraction of "free" brain mitochondria (non-synaptic) isolated by the method of Clark & Nicklas (1970). (J. Biol. Chem. 245, 4724-4731). Both mitochondrial fractions are shown to be relatively pure, metabolically active and well coupled. 2. The oxidation of a number of substrates by synaptic and non-synaptic mitochondria was studied and compared. Of the substrates studied, pyruvate plus malate was oxidized most rapidly by both mitochondrial populations. However, the non-synaptic mitochondria oxidized glutamate plus malate almost twice as rapidly as the synaptic mitochondria. 3. The activities of certain tricarboxylic acid-cycle and related enzymes in synaptic and non-synaptic mitochondria were determined. Citrate synthase (EC 4.1.3.7), isocitrate dehydrogenase (EC 1.1.1.41) and malate dehydrogenase (EC 1.1.1.37) activities were similar in both fractions, but pyruvate dehydrogenase (EC 1.2.4.1) activity in non-synaptic mitochondria was higher than in synaptic mitochondria and glutamate dehydrogenase (EC 1.4.1.3) activity in non-synaptic mitochondria was lower than that in synaptic mitochondria. 4. Comparison of synaptic and non-synaptic mitochondria by rate-zonal separation confirmed the distinct identity of the two mitochondrial populations. The non-synaptic mitochondria had higher buoyant density and evidence was obtained to suggest that the synaptic mitochondria might be heterogeneous. 5. The results are also discussed in the light of the suggested connection between the heterogeneity of brain mitochondria and metabolic compartmentation. 相似文献
88.
The authors develop an eigth-order model for bending of transversally isotropic plates and use integral transforms and a collocation
method to form a line-spring model for a cracked plate. The eigth-order model allows satisfaction of the three standard plate
bending boundary conditions; the normal moment, twisting moment, and transverse shear force, and an additional shear stress
resultant that allows analysis of transverse normal stresses near the crack tip. The line-spring model is used to develop
geometry correction factors for bending of finite-thickness plates, accounting for transverse shear deformation and pressurization
of the plate near the crack tip. The line-spring model is then applied to the problem of a plate with a reinforced crack,
and the results are used to validate an interpolation solution based on an energy method. While not explicitly analysed, the
models are applicable to many problems, including bending of bonded repairs, fracture and fatigue of composite and layered
materials, surface cracks, crack tip plasticity and crack closure or crack face interaction. 相似文献
89.
Hanson William E.; Creswell John W.; Clark Vicki L. Plano; Petska Kelly S.; Creswell J. David 《Canadian Metallurgical Quarterly》2005,52(2):224
With the increased popularity of qualitative research, researchers in counseling psychology are expanding their methodologies to include mixed methods designs. These designs involve the collection, analysis, and integration of quantitative and qualitative data in a single or multiphase study. This article presents an overview of mixed methods research designs. It defines mixed methods research, discusses its origins and philosophical basis, advances steps and procedures used in these designs, and identifies 6 different types of designs. Important design features are illustrated using studies published in the counseling literature. Finally, the article ends with recommendations for designing, implementing, and reporting mixed methods studies in the literature and for discussing their viability and continued usefulness in the field of counseling psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Mapping vegetation in Yellowstone National Park using spectral feature analysis of AVIRIS data 总被引:1,自引:0,他引:1
Raymond F Kokaly Don G DespainRoger N Clark K.Eric Livo 《Remote sensing of environment》2003,84(3):437-456
Knowledge of the distribution of vegetation on the landscape can be used to investigate ecosystem functioning. The sizes and movements of animal populations can be linked to resources provided by different plant species. This paper demonstrates the application of imaging spectroscopy to the study of vegetation in Yellowstone National Park (Yellowstone) using spectral feature analysis of data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). AVIRIS data, acquired on August 7, 1996, were calibrated to surface reflectance using a radiative transfer model and field reflectance measurements of a ground calibration site. A spectral library of canopy reflectance signatures was created by averaging pixels of the calibrated AVIRIS data over areas of known forest and nonforest vegetation cover types in Yellowstone. Using continuum removal and least squares fitting algorithms in the US Geological Survey's Tetracorder expert system, the distributions of these vegetation types were determined by comparing the absorption features of vegetation in the spectral library with the spectra from the AVIRIS data. The 0.68 μm chlorophyll absorption feature and leaf water absorption features, centered near 0.98 and 1.20 μm, were analyzed. Nonforest cover types of sagebrush, grasslands, willows, sedges, and other wetland vegetation were mapped in the Lamar Valley of Yellowstone. Conifer cover types of lodgepole pine, whitebark pine, Douglas fir, and mixed Engelmann spruce/subalpine fir forests were spectrally discriminated and their distributions mapped in the AVIRIS images. In the Mount Washburn area of Yellowstone, a comparison of the AVIRIS map of forest cover types to a map derived from air photos resulted in an overall agreement of 74.1% (kappa statistic=0.62). 相似文献