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91.
Lipid metabolism of male Fisher 344 rats aged 2–24 months was studied. Serum and liver cholesterol levels did not display the age-related gradual increase seen in other rat strains. An increase in the serum plus liver cholesterol pool from 2 to 6 months was followed by a plateau through 18 months and then another increase at 24 months of age. The triglyceride pool increased from 2 to 6 months and then remained unchanged through 24 months of age. Cholesterol synthesis from acetate decreased 50% between 2 and 9 months and fell only slightly through 24 months of age. Assay of 3-hydroxy-3-methyl glutaryl Coenzyme A (HMG-CoA) reductase showed a similar pattern but did not decrease further after 9 months of age. Cholesterol 7α hydroxylase activity was not significantly altered by age. These age- and strain-related differences present an opportunity for a comparative study of the aging process using the parameters of lipid metabolism as indicators.  相似文献   
92.
Explores the impact of physical abnormalities on interpersonal relationships and investigates 1 technique available to the stigmatized to influence that impact. This technique is to indicate that the abnormality may be freely discussed or that it is a forbidden topic. The 60 male undergraduate Ss were introduced to an ostensibly naive student who was in reality a confederate and appeared either as an amputee in a wheelchair or as only slightly crippled. The shocks Ss were induced to administer the confederate were less painful when he was severely than when he was slightly crippled. It was concluded that all stigmata do not have the same interpersonal consequences and that the most marked effects occur for behaviors of which Ss have little awareness. (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
This study investigates the writing stylechange of two Turkish authors, Çetin Altanand Yaar Kemal, in their old and newworks using respectively their newspapercolumns and novels. The style markers are thefrequencies of word lengths in both text andvocabulary, and the rate of usage of mostfrequent words. For both authors, t-tests andlogistic regressions show that the length ofthe words in new works is significantly longerthan that of the old. The principal componentanalyses graphically illustrate the separationbetween old and new texts. The works arecorrectly categorized as old or new with 75 to100% accuracy and 92% average accuracy usingdiscriminant analysis-based cross validation. The results imply higher time gap may havepositive impact in separation andcategorization. For Altan a regressionanalysis demonstrates a decrease in averageword length as the age of his column increases. One interesting observation is that for oneword each author has similar preference changesover time.  相似文献   
94.
A method for recovering the three-dimensional structure of moving rigid and jointed objects from several single camera views is presented. The method is based on the fixed axis assumption: all movement consists of translations and rotations about an axis that is fixed in direction for short periods of time. This assumption makes it possible to recover the structure of any group of two or more rigidly connected points. The structure of jointed objects is recovered by analyzing them as collections of rigid parts, and then unifying the structures proposed for the parts. The method presented here has been tested on several sets of data, including movies used to demonstrate human perception of structure from motion.  相似文献   
95.
Pure cellulose was converted to oil by direct thermochemical aqueous-phase liquefaction. A model for yields from conversion was determined by regression of data from autoclave experiments. The conditions for optimum yield were found to be 315 °C, using 0.9 g equivalents/l of carbonate ion, and CO at 1.72 MPa (gauge pressure). Temperature had the most significant effect on yield. Analysis of the cellulose-derived product indicated a much larger fraction of aromatic carbon than had been thought possible previously. Compared to petroleum crude oil, the cellulose-derived oil had a greater fraction of high-molecular-weight components, a greater distillation residuum, greater viscosity, and greater oxygen content. Distillates of the cellulose-derived oil also contained significantly more oxygen than petroleum, but could potentially replace kerosene or related fuels.  相似文献   
96.
This is the final report of a panel set up by the U.S. Department of Energy (DOE) Fusion Energy Sciences Advisory Committee (FESAC) in response to a charge letter from Dr. Ray Orbach (Appendix A). In that letter, Dr. Orbach asked FESAC for an assessment of the present status of inertial fusion energy (IFE) research carried out in contributing programs. These programs include the heavy ion (HI) beam, the high average power laser (HAPL), and Z-Pinch drivers and associated technologies, including fast ignition (FI). This report, presented to FESAC on March 29, 2004, and subsequently approved by them (Appendix B), presents FESAC's response to that charge.  相似文献   
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Accurate maps representing seagrass spatial distribution are essential components for effective monitoring and management of coastal vegetated habitats. Satellite and acoustic remote sensing provide valuable spatial data for seagrass mapping, though few studies have evaluated the complementarity of these methods. In this study, the complementarity of seagrass mapping was assessed through comparison of acoustic and satellite remote-sensing data sets. QuickBird® satellite imagery representing the seagrass landscape of the Richibucto estuary, New Brunswick, Canada, was classified through an object-based procedure and evaluated against a single-beam sonar data set. Acoustic percentage cover values were classified into binary presence/absence format through the application of a decision threshold, allowing comparison with satellite data using the error matrix and derived metrics. Though the binary satellite classification resulted in relatively high accuracy compared with independent ground reference data, agreement between satellite and acoustic data sets was limited. Local differences in seagrass prevalence and patchiness affected classification accuracy, highlighting the potential for under- or overestimating seagrass cover when applying bay-scale classification to areas with different landscape structure. These results emphasize the importance of landscape context in seagrass mapping. Satellite and acoustic remote sensing were seen to fundamentally differ in their depiction of the landscape. Comparison of multiple remote-sensing methods allowed for assessment of complementarity as well as ecologically relevant insight to seagrass spatial dynamics, with implications for mapping and monitoring of seagrass habitats.  相似文献   
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