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991.
Armstrong Donkoh Paul J Moughan Patrick C H Morel 《Journal of the science of food and agriculture》1995,67(3):359-366
The aim was to compare a recently developed peptide alimentation method and the protein-free and regression methods for determining endogenous ileal nitrogen (N) and amino acid excretion in the rat, and to apply the endogenous loss estimates to determine the true ileal digestibility of a meat and bone meal (MBM). Preliminary investigations determined the effect of the time of sampling of digesta after a meal (slaughter method) for rats given a protein-free or an enzymically hydrolysed casein (EHC) based diet, on ileal digesta and endogenous N excretion. There was a significant (P < 0.05) effect of the time of sampling on the amount of digesta collected and the endogenous N excretion for both the EHC and protein-free fed rats. The amount of digesta collected from the terminal 20 cm of ileum and the endogenous N excretion for both the EHC and protein-free fed rats were greatest and least variable at 3 h post-feeding. In the main study, endogenous ileal amino acid excretions were determined in the growing rat fed an EHC-based diet (n = 6) and with subsequent treatment of the digesta using ultrafiltration or in six rats given a protein-free diet or by extrapolation from data for 30 animals given five diets which contained graded levels of MBM as the sole protein source. For the EHC treatment, the ileal digesta precipitate plus retentate was used to determine the endogenous flows. The ultrafiltration step excludes unabsorbed dietary amino acids from the measure of endogenous loss. Chromic oxide was the reference marker in all diets. The endogenous N flows determined by the protein-free and regression methods were similar but both significantly (P < 0.01) lower than those for rats fed the EHC-based diet. The mean endogenous ileal N flows determined by the peptide alimentation method, the protein-free and regression approaches were 1866, 1103 and 1019 μg g?1 freeze dry matter intake, respectively. The endogenous amino acid flows at the terminal ileum were lower when determined using the traditional protein-free or regression methods. The true ileal digestibility coefficients for MBM were considerably higher based on the EHC versus protein-free endogenous flows. 相似文献
992.
993.
Paul H. Cheney 《Information & Management》1984,7(4):209-214
Several individual characteristics of computer programmers (self- esteem, level of experience, and mathematical aptitude); four organizational factors (perceived supervisory initiated structure, perceived supervisor consideration, perceived level of performance feedback, and perceived degree of participation in organizational decisions); and five task characteristics (skill variety, task variety, task significance, autonomy, and feedback) are related to computer programmer productivity and job satisfaction. Measurement was accomplished via questionnaires; least squares multiple regression was used to test the hypotheses. 相似文献
994.
Zarbatany Lynne; Hartmann Donald P.; Gelfand Donna M.; Vinciguerra Paul 《Canadian Metallurgical Quarterly》1985,21(1):97
Tested the notion that observed sex differences in children's altruistic reputations that favor girls are due to sex-biased items found in commonly used peer-assessment measures. A gender-fair assessment of altruistic reputation was attempted by including items that were empirically derived examples of masculine, feminine, and gender-neutral prosocial behaviors. These items were based on prosocial incidents reported by 65 5th graders. 123 additional 5th graders were asked to respond to the new items by nominating 2 classmates most likely to engage in prosocial behavior or by indicating which sex was most likely to perform the behaviors. Results show that, overall, females were judged to be more altruistic than males. However, endorsement differed across item content: Males were selected more often for masculine items and females more often for feminine and sex-neutral items. In general, males endorsed males for helpful behaviors and females endorsed females. The gender-rating form of the test produced responses more closely related to the empirically based item-gender-content classes than did the peer-nomination form. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Paul F. Basch 《Journal of chemical ecology》1986,12(8):1679-1686
An understanding of reproductive function is important for control of parasitic helminths. In cestodes and trematodes virtually nothing is known about regulatory and coordinating mechanisms that control maturation, gamete formation, egg production, and related processes. Neurosecretory neurons have been reported in various species but specific modes of action of neurohormones have yet to be demonstrated. The role of ecdysone is being investigated. 相似文献
996.
997.
Personality trait structure as a human universal. 总被引:1,自引:0,他引:1
Patterns of covariation among personality traits in English-speaking populations can be summarized by the five-factor model (FFM). To assess the cross-cultural generalizability of the FFM, data from studies using 6 translations of the Revised NEO Personality Inventory (P. T. Costa & R. R. McCrae, 1992) were compared with the American factor structure. German, Portuguese, Hebrew, Chinese, Korean, and Japanese samples (N?=?7,134) showed similar structures after varimax rotation of 5 factors. When targeted rotations were used, the American factor structure was closely reproduced, even at the level of secondary loadings. Because the samples studied represented highly diverse cultures with languages from 5 distinct language families, these data strongly suggest that personality trait structure is universal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Foued Ameur Paul Fischer Klaus-U. Höffgen Friedhelm Meyer auf der Heide 《Acta Informatica》1996,33(7):621-630
A pac-learning algorithm is -space bounded, if it stores at most examples from the sample at any time. We characterize the -space learnable concept classes. For this purpose we introduce the compression parameter of a concept class and design our Trial and Error Learning Algorithm. We show : is -space learnable if and only if the compression parameter of is at most . This learning algorithm does not produce a hypothesis consistent with the whole sample as previous approaches e.g. by Floyd,
who presents consistent space bounded learning algorithms, but has to restrict herself to very special concept classes. On
the other hand our algorithm needs large samples; the compression parameter appears as exponent in the sample size. We present
several examples of polynomial time space bounded learnable concept classes: – all intersection closed concept classes with
finite VC–dimension. – convex -gons in . – halfspaces in . – unions of triangles in . We further relate the compression parameter to the VC–dimension, and discuss variants of this parameter.
Received May 24, 1994 / July 4, 1995 相似文献
999.
A robotic vision system for object identification and manipulation using synergetic pattern recognition 总被引:5,自引:0,他引:5
This paper discusses the application of the synergetic pattern recognition method to a robotic vision system for workpiece identification and manipulation in automated flexible manufacturing environments. The original synergetic algorithm is extended to allow its pattern attention parameters to have different values. Stability analysis of the extended recognition model indicates that the prototype patterns are the only stable patterns and undesired spurious patterns cannot exist. A simple scheme for tuning attention parameters is developed. Simulation results show that the number of object misclassification is reduced significantly with this extension. In addition, an image preprocessing procedure enables synergetic recognition to be simultaneously invariant to spatial pattern translation, rotation, and scaling; while an approach for recovering position, orientation, and size information is also proposed. Simple and efficient task-directed and object-specific strategies for robotic workpiece manipulation are now easy to implement based on these results and procedures. 相似文献
1000.
Experiments were conducted to test the hypothesis that alleiopathic effects of ferulic acid (FA) may be altered by the temperature conditions of the growth environment. Growth of grain sorghum and soybean seedlings over a 10-day treatment period showed that a significant interaction effect occurred between environmental temperatures and FA treatments. Sorghum grown with an average day temperature of 37 °C and soybeans grown at 34 °C had greater dry weight reductions caused by FA than when the respective environments were 8 °C and 11 °C lower. The threshold concentration for inhibition of sorghum growth was 0.2 mM FA under the hot conditions and 0.4 mM FA with the cooler conditions. Soybeans were more sensitive than sorghum, and these inhibition thresholds for the hot and cool environments were 0.1 and 0.25 mM FA. These results demonstrate that temperature stress enhances allelochemical inhibition and indicate that interactions with the environment are an important consideration for understanding allelopathy. 相似文献