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221.
In two experiments, thirsty rats consumed a compound of sucrose and a non-preferred flavor. In Experiment 1, a conditioned preference was observed in the experimental group when animals were tested both thirsty and hungry, but not when they were tested just thirsty. Animals in the control group, which experienced the flavor and the sucrose unpaired, never showed a preference. Experiment 2 replicated the absence of a preference in the experimental group when rats were tested thirsty, but provided evidence that a flavor-taste association had been formed during training. After conditioning, sucrose was paired with LiCl in group Dev whereas it was unpaired in group NonDev. The sucrose devaluation produced a decrease in CS preference in group Dev, and an increment in group NonDev. Taken together, these results show that preference for a non-preferred flavor can be readily observed after pairings with the positive consequences of the US (calories or absence of an expected illness) rather than with a palatable flavor.  相似文献   
222.
The main purpose of this essay is not to give a full-scale and systematic exploration of the historical process concerning the acceptance of Habermas’ works in the Chinese-spoken world but to examine the historical effect of Habermas in the Chinese-spoken context and try to find a proper way to establish a good relationship between Habermas and the Chinese-spoken world by discussing the introduction, study, and application of Habermas’ most famous work, The Structural Transformation of the Public Sphere, by Chinese scholars in recent years. Translated from Xiandai zhexue, 2005:1  相似文献   
223.
目前,语言产生领域的多数研究都集中在口语词语产生方面,许多研究者针对不同的语言系统的特色,对功能词进行了大量跨语言的研究。汉语量词是汉藏语系独有的功能词,本研究采用词图干扰范式,以名词短语和简单名词两种不同的图片命名任务,探讨了汉语量词的产生过程。实验结果发现,在名词短语命名任务下,存在量词的一致性效应;在名词命名的任务下,则不存在这种一致性效应。研究还发现语义干扰效应在两种不同命名任务下出现了分离。语义干扰效应只在命名名词的任务下出现,在命名名词短语的任务下未被发现。  相似文献   
224.
Owing to their very high strength, nanocrystalline metals have been extensively studied over the recent years. The direct Hall–Petch law, empirically proportioning the material strength to the inverse square root of its grain size has been shown to break down below a grain size of the order of tenths of nanometers. This phenomenon has been widely rationalized as a gradual switch from intragrain mediated deformation mechanisms to grain boundary mediated deformation mechanisms. This transition has been observed in many finite element simulations, despite the intrinsic restriction of necessarily limiting the nanocrystalline representative assembly to only a few grains. Such a limitation is generally overlooked, and its influence on an uniaxial tension test – when compared to a complete sample of millions of grains – ignored. We propose here to quantify the approximation done by considering a finite number of grains by means of a simple analytical model based on the early work of Stevens [R.N. Stevens, Philos. Mag. 23 (1971) p. 265]. The finite element approximation is demonstrated to be relatively good, even down to only three grains in width, and a method to “correct” the stress-strain curves of small representative volumes is proposed.  相似文献   
225.
Since the 1930s it has been widely acknowledged that agricultural crop diversity is being lost at an alarming rate. The international response to this genetic erosion has principally taken the form of ex situ genebanks. In these facilities and in the international regulatory frameworks that now surround them, it is genetic diversity that is the focus of conservation efforts. This focus, however, passes over the many other important diversities—both biological and social (or ‘biosocial’)—that exist in, and depend on, agricultural environments. These diversities cannot be conserved in genebanks. In addition to failing to actually conserve agricultural diversity (in any full sense of the term), ex situ banking projects also produce important potential inequalities—in terms of which material is banked and who has access to it. If, however, we refuse to accept an exclusive focus on the genetic components of plants, and instead insist on a brand of conservation that includes whole biosocial, more-than-human communities, then the role of banked resources must be radically rethought. Genebanks might instead take the place of central nodes in networks of diversity sharing, helping to keep plant varieties growing and circulating. This focus, in turn, requires that we also pay more critical attention to the various economic, legal and other mechanisms that prevent or stifle the flow and development of plant genetic resources in/to agricultural communities—especially those of peasant and indigenous farmers that play such a crucial role in conserving the world's (agro)biodiversity.  相似文献   
226.
The mechanical softening behaviour of micrometre-scale metals (free-standing metal foils and wires) with decreasing either the geometrical or the microstructural scale (i.e. the smaller, the weaker) has recently been reported. Here, we present a mechanism-based model to understand the softening behaviour, which is based on competition between the effects of surface grain relaxation and the interior grain strengthening effect. The model describes well the yield stress of Cu foils with different ratios of the thickness to grain size.  相似文献   
227.
ABSTRACT

Several studies have established the impact of conceptually similar context on the emergence of “Context-Effect” (CE). None of these studies included the Re-pair/rearrange condition at the test, which prevented them from being conclusive about the exact process (binding/ensemble or familiarity) that was affected by the conceptually similar context. To this end, in the present study faces (target to be remembered) were presented in the context of either words (W) or picture (P) scenes, and at test Re-pair was added as one of the context conditions. At test two groups were presented with the same context as in study (consistent condition) (WW & PP), and two groups with the inconsistent condition (WP & PW). Results showed no familiarity effect when only the conceptual match was preserved (i.e., inconsistent condition) and both effects of binding and familiarity when both conceptual and perceptual match were present (i.e., consistent condition). Thus, the semantic association between a face and context could serve as recognition cues even when modality has been changed, but the label remained constant.  相似文献   
228.
ABSTRACT

The effect of Retrieval Practice refers to the phenomenon that taking a practice test is more effective for learning than re-study, probably due to the benefit from processes underlying successful retrievals during practice. However, it is rarely studied whether other processes (e.g., metacognitive monitoring) during retrieval practice may also play an important role. In two experiments, we examined whether the effectiveness of retrieval was affected by subjects’ confidence in their retrieval success. Subjects studied word-pairs and rated their confidence after each practice test trial (cued-recall in Exp.1, multiple choice in Exp.2), or re-study trial. In both experiments, we observed the classic retrieval practice effect. Moreover, in Exp.2, the benefits differed as a function of subjects’ confidence in their retrieval performance: the effect of retrieval practice only emerged for high-confidence trials with higher than 56% confidence. In summary, the retrieval practice only facilitates the retention of correct answers with high confidence.  相似文献   
229.
ABSTRACT

Although previous research on retrieval practice (RP) has predominantly featured stimuli with discrete right-or-wrong answers, continuous measures offer potentially greater sensitivity in assessing the effects of RP on memory precision. The present study used a colour gradient (125 points ranging from magenta to yellow) as a continuous response variable. The colours of different images were learned through either RP or restudy and either one or three cycles of practice after initial study. On a delayed final test, participants’ memory was assessed for each item’s colour. Participants also created per-item intervals representing the region where they believed the correct colour most likely to have been. We found that repeated rounds of RP enhanced the correspondence between responses and the correct colour. In addition, RP led to participants creating more accurate (correct answers were more likely to be within the participant-specified intervals) and more precise (narrower) intervals relative to restudy, suggesting that RP enhances the precision of memories.  相似文献   
230.
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