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81.
A group of rhesus monkeys, consisting of 8 matrilines of up to 4 generations each and 9 unrelated adult males, was studied for 2 yrs. Group size varied between 75 and 91 individuals. Data collection consisted of ad lib recording of agonistic interactions. Results indicate that adult male interference in agonistic episodes was strongly biased against adolescent and adult male participants, whereas adult female interference was biased in favor of kin and in support of younger animals against older animals. Although natal males also were biased in favor of their kin, their selective targeting of sexually mature males was independent of kinship. Adolescent males targeted adult males, but only in defense of kin. It is suggested that this selective interference against adolescent and adult males by adult males has the potential to profoundly modify male agonistic participation in intragroup encounters after puberty. Because female support is influenced primarily by kinship, females less consistently interfere against male agonistic participants. Adult males may therefore play an important role in the socialization of male agonistic expression. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Grady Cheryl L.; Bernstein Lori J.; Beig Sania; Siegenthaler Amy L. 《Canadian Metallurgical Quarterly》2002,17(1):7
Age-related differences in brain activity mediating face recognition were examined using positron emission tomography. Participants encoded faces using a pleasant-unpleasant judgement, a right-left orientation task, and intentional learning. Scans also were obtained during recognition. Both young and old groups showed significant effects of encoding task on recognition accuracy, but older adults showed reduced accuracy overall. Increased brain activity in older adults was similar to that seen in young adults during conditions associated with deeper processing, but was reduced during the shallow encoding and recognition conditions. Differential correlations of brain activity and behavior were found that suggest older adults use unique neural systems to facilitate face memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
84.
Comparative psychologists study the "mind" of animals by studying what animals do and what animals are capable of doing. Different investigators address questions of proximal cause, motivation, physiological mechanism, evolutionary and ontogenetic considerations, as well as functional consequences. Some use animal subjects to explore universal theories of behavior; others focus on the diversity of behavior itself. A number of theoretical positions guide the different approaches. Some theories have been proven woefully inadequate, even fatally flawed, but no discipline thrives solely on the validity of a single theory. Let us preserve the data and discard discredited hypotheses, but let us continue to advance our discipline and refrain from wallowing in remorse over erroneous earlier ideas. Ideas are exciting but data endure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
There is increasing concern about the misuse of drugs among the elderly. We assessed misuse, including drug usage, drug interactions across pharmacologic classes, and multiple drugs in the same pharmacologic class, in a community sample of sixty-five 74-year-olds, and evaluated its relation to stress and coping processes and psychological and somatic health. Assessments were made repeatedly over a 6-month period. Results indicated that misuse was multidimensional and widespread. Misusers did not differ from nonmisusers on antecedent psychosocial variables, nor did they report more hassles or cope differently than nonmisusers. However, misusers and nonmisusers differed on their subjective experience of stressful encounters; misusers experienced their hassles as more intense, and they experienced more threat emotions and more dissatisfaction with their coping than did nonmisusers. Misuse was also associated with long-term psychological satisfaction, psychological symptoms, and somatic health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Solana F. Takamadate C. Bernstein I. M. Thompson W. 《Metallurgical and Materials Transactions A》1987,18(6):1023-1028
Metallurgical and Materials Transactions A - The ability of retained austenite to affect stress corrosion cracking susceptibility has been examined in two steels, containing mechanically stable and... 相似文献
87.
For pt.I see ibid., vol.13, no.2, p.316-22 (1998). This paper presents the results of laboratory aging tests on polymeric cable terminations. The goals of the laboratory aging were two-fold: (1) develop an accelerated aging test that can simulate the changes produced in the field, and (2) provide an assessment on the magnitude of aging induced changes on the electrical performance of terminations. Monitoring leakage current and material changes during laboratory tests were useful for assessing the variations possible in aging due to experimental parameters used. It has been shown that a laboratory aging test that is based on evaluating the termination's leakage current suppression capability and the ability to withstand a moderate level of discharge activity is suitable not only for assessing the long term performance, but also for ranking the electrical performance in accordance with field exposure 相似文献
88.
Byung‐Eul Jun Dennis S. Bernstein N. Harris McClamroch 《International Journal of Adaptive Control and Signal Processing》2010,24(3):203-210
This paper proposes a procedure for identifying the inertia matrix of a rotating body. The procedure based on Euler's equation governing rotational motion assumes errors‐in‐variables models in which all measurements, torque as well as angular velocities, are corrupted by noises. In order for consistent estimation, we introduce an extended linear regression model by augmenting the regressors with constants and the parameters with noise‐contributed terms. A transformation, based on low‐pass filtering, of the extended model cancels out angular acceleration terms in the regressors. Applying the method of least correlation to the model identifies the elements of the inertia matrix. Analysis shows that the estimates converge to the true parameters as the number of samples increases to infinity. Monte Carlo simulations demonstrate the performance of the algorithm and support the analytical consistency. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
89.
Parameter Sweep Workflows for Modelling Carbohydrate Recognition 总被引:1,自引:0,他引:1
Tamas Kiss Pamela Greenwell Hans Heindl Gabor Terstyanszky Noam Weingarten 《Journal of Grid Computing》2010,8(4):587-601
Carbohydrate recognition is a phenomenon critical to a number of biological functions in humans. Understanding the dynamic
behaviour of oligosaccharides should help in the discovery of the mechanisms which lead to specific and selective recognition
of carbohydrates by proteins. Computer programs which can provide insight into such biological recognition processes have
significant potential to contribute to biomedical research if the results of the simulation can prove consistent with the
outcome of conventional wet laboratory experiments. In order to validate these simulation tools and support their wider uptake
by the bio-scientist research community, high-level easy to use integrated environments are required to run massively parallel
simulation workflows. This paper describes how the ProSim Science Gateway, based on the WS-PGRADE Grid portal, has been created
to execute and visualise the results of complex parameter sweep workflows for modelling carbohydrate recognition. 相似文献
90.
The mechanism responsible for post-soft breakdown leakage current increase in ultra-thin oxides depends on the nature of the conducting filament formed at the instant of dielectric breakdown. The conductance of the filament formed during soft breakdown has been observed to be either stable until hard breakdown occurs or to increase continually with time. The acceleration factors for predicting hard breakdown are different in each case. Recent experimental results suggest that the “hardness” of the first breakdown influences the type of conducting filament formed during the soft breakdown event the time in which hard breakdown subsequently occurs. Electron current-induced defect formation appears to be the driving force for the eventual hard breakdown event. 相似文献