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91.
Five studies examined the hypotheses that when people experience positive affect, those low in self-esteem are especially likely to dampen that affect, whereas those high in self-esteem are especially likely to savor it. Undergraduate participants' memories for a positive event (Study 1) and their reported reactions to a success (Study 2) supported the dampening prediction. Results also suggest that dampening was associated with worse mood the day after a success (Study 2), that positive and negative affect regulation are distinct, that self-esteem is associated with affect regulation even when Neuroticism and Extraversion are controlled (Studies 3 and 4), and that self-esteem may be especially important for certain types of positive events and positive affect regulation (Study 5). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Groshek Frank; Kerfoot Erin; McKenna Vanessa; Polackwich Alan S.; Gallagher Michela; Holland Peter C. 《Canadian Metallurgical Quarterly》2005,119(1):202
In Pavlovian appetitive conditioning, rats often acquire 2 classes of conditioned responses: those whose form is determined by the reinforcer, and those whose form is determined by characteristics of the conditioned stimulus (CS). Consistent with the results of previous lesion studies, reversible inactivation of amygdala central nucleus function during pairings of an auditory CS with food prevented the acquisition of conditioned orienting responses specific to auditory CSs, whereas food-related conditioned behaviors were acquired normally. Neither inactivation nor posttraining neurotoxic lesions of the central nucleus affected the expression of previously acquired conditioned orienting. Thus, although the central nucleus is critical to the acquisition of information required for conditioned orienting to auditory cues, it is not needed for maintaining this information for later use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Several animal studies have shown that there is a positive correlation between locomotor activity in response to a novel environment and acquisition of drug self-administration behavior. This finding led to the assumption that animals with heightened reactivity to novel environments are more sensitive to the rewarding effects of drugs compared with animals with reduced reactivity. But are these individuals really more responsive to drugs, or could they have enhanced sensitivity to rewards in general or even simply be better learners? In the previous issue of this journal, J. M. Mitchell, C. L. Cunningham, and G. P. Mark (2005) (see record 2005-03585-010), investigated these important matters. They reported that the locomotor response to a novel environment does not predict responding for cocaine but reflects overall differences in the ability to learn operant tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Summary This paper analyzes Internet diffusion among various organizations, based on daily observation of second- level domain name
registrations under the “.it”ccTLD. In particular, we analyzed domain names registered by organizations in the non-profit
sector.<span style='font-size:12.0pt;mso-ansi-language: HU'>The penetration rate, calculated according to the number of organizations,
was computed for various widely separated geographic levels (regions). A concentration analysis was performed in order to
determine whether the geographical distribution of Internet use in Italy is less concentrated with respect to both the number
of existing institutions and income distribution, suggesting a diffusive effect.<span lang=EN-US style='font-size:12.0pt;
mso-ansi-language:EN-US'>Regression analysis was performed using demographic, social, economic and infrastructure indicators.
Results show that<span style='font-size:12.0pt;mso-ansi-language:HU'>a “social digital divide”exists, both in terms of geographical
distribution (i.e., in macro-areas - Northern, Central, and Southern Italy - and at the regional level) and in terms of the
legal status of the organizations, and that this digital divide will probably decrease in the future. 相似文献
95.
Passer Michael W.; Kelley Harold H.; Michela John L. 《Canadian Metallurgical Quarterly》1978,36(9):951
Conducted studies to determine empirically the dimensions underlying attributions made for negative behavior in a close interpersonal relationship (a marriage). 96 university students rated the similarity of 13 causes given either by the enactor of a negative behavior (i.e., the actor) or by the person affected by the behavior (the partner or spouse). A multidimensional scaling analysis of these data yielded 2 dimensions in each condition. The interpretation of these dimensions was guided by data from 68 additional Ss who rated the 13 causes on bipolar scales (e.g., temporary–permanent). Dimension 1 in both conditions was interpreted as "positive vs negative attitude toward spouse." Dimension 2 of the actor condition was interpreted as "intentional vs unintentional" and Dimension 2 of the partner condition as "actor's traits vs circumstances or states." These dimensions are discussed in relation to the a priori causal distinctions made in current attribution writings and previous findings concerning actor–observer biases. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
97.
Bucci David J.; Chiba Andrea A.; Gallagher Michela 《Canadian Metallurgical Quarterly》1995,109(1):180
Male and female Long-Evans rats were tested in the Morris water maze at age 6 mo. A place training procedure, in which rats learned the position of a camouflaged platform, was followed by cue training, in which rats escaped to a visible platform. No sex difference was found in place learning ability. Search accuracy on probe trials, when the platform was unavailable, was also equivalent for the male and female groups. These results contrast with previous studies of rodents at younger ages, which have reported a male advantage in spatial learning. It is suggested that the age at which rats are assessed may be an important factor, possibly reflecting a different course in the relatively protracted maturation of the hippocampus in male and female rats. The results of this investigation are also discussed with reference to studies of sex differences for spatial abilities in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Bonanomi Cristian Balletti Simone Lecca Michela Anisetti Marco Rizzi Alessandro Damiani Ernesto 《Multimedia Tools and Applications》2020,79(13-14):8599-8626
Multimedia Tools and Applications - In this paper we present a dataset of images to test the performance of image processing algorithms, in particular demosaicing and denoising methods. Despite the... 相似文献
99.
Mono-material in the manufacturing of oil-based plastic bottles has been so far not considered because of the poor flexibility of polyethylene terephthalate (PET). The undercuts of PET caps (i.e., the threads of the screw caps) would be torn-off during the ejection step of the injection/compression molding processes that are commonly used to fabricate them. In this respect, the present work deals with the design and development of innovative biodegradable polyester-based blends with high flexibility, intended for the manufacturing of screw-cap, being this element the most critical in the implementation of the complete bottle. The blend is based on polylactic acid and it is tailored for injection molding of tamper-evident screw plastic caps by the addition of another biodegradable polyester, that is, polybutylene adipate-co-terephthalate. The effect of the addition of a barrier agent, polyvinyl alcohol, on the overall behavior of the blends was also studied in the perspective of the implementation of caps featuring barrier properties against water vapor and oxygen. The same material could be, however, easily tailored for the fabrication of the bottle body and printed label to get to the mono-material bottle. Twin-screw corotating extrusion of the compound, injection molding of the plastic material for the fabrication of the screw caps, and evaluation of the thermophysical and mechanical properties of the screw caps are hereinafter discussed. The biodegradable polyester-based blends are found to be suitable for injection molding of the tamper-evident screw caps, exhibiting adequate flexibility during ejection from the mold. The screw caps can also boast appreciable mechanical strength and impact resistance as well as good thermal stability. 相似文献
100.
Taxanes represent one of the most promising classes of anticancer agents. Unfortunately, their clinical success has been limited by the insurgence of cellular resistance, mainly mediated by the expression of the MDR phenotype or by microtubule alterations. However, the remarkable relevance of paclitaxel and docetaxel in clinical oncology stimulated intensive efforts in the last decade to identify new derivatives endowed with improved activities towards resistant tumor cells, resulting in a huge number of novel natural and synthetic taxanes. Among them, several structurally different derivatives were found to exhibit a promising behavior against the MDR phenotype in terms of either MDR inhibiting properties, or enhanced cytotoxicity compared to parental drugs, or both. On the other hand, only in more recent years have the first taxanes retaining activity against resistant cancer cells bearing alterations of the tubulin/microtubule system emerged. This review describes the main molecular mechanisms of resistance to paclitaxel and docetaxel identified so far, focusing on the advances achieved in the development of new taxanes potentially useful for the treatment of resistant tumors. 相似文献