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Differences in response rates to a three-wave mail survey were assessed when the covering letters were signed by three versus one researcher. 375 surveys including covering letters signed by three researchers and 375 surveys including covering letters signed by one researcher were sent. A follow-up mailing was used to increase the response rate. 199 surveys were returned (53.5%) in which the covering letter had three researchers, and 218 when the covering letter had one researcher (58.7%), not a significantly different distribution.  相似文献   
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Graphene is a nanomaterial with many promising and innovative applications, yet early studies indicate that graphene may pose risks to humans and the environment. According to ideas of responsible research and innovation, all relevant actors should strive to reduce risks related to technological innovations. Through semi-structured interviews, we investigated the idea of graphene as a risk (or not) held by two types of key actors: graphene researchers and innovation advisors at universities, where the latter are facilitating the movement of graphene from the laboratory to the marketplace. The most common idea found is that graphene is not a risk due to, e.g., low toxicity, low amounts produced/used, and its similarity to harmless materials (being “just carbon”). However, some researchers and advisors also say that graphene is a risk, e.g., under certain conditions or due to a lack of risk-related information. We explain the co-existence of these seemingly contradictory ideas through (1) the semantic ambiguity of the word risk and (2) a risk/no-risk rhetoric, where risks are mentioned rhetorically only to be disregarded as manageable or negligible. We suggest that some of the ideas held by the researchers and innovation advisors constitute a challenge to responsible research and innovation regarding graphene. At the same time, we acknowledge the dilemma that the discourse of responsible innovation creates for the actors: denying graphene risks makes them irresponsible due to a lack of risk awareness, while affirming graphene risks makes them irresponsible due to their everyday engagement in graphene development. We therefore recommend more research into what researchers and innovation advisors should do in practice in order to qualify as responsible.  相似文献   
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Previous research regarding the beneficial effects of auditory stimuli on learning and memory in humans has been inconsistent. In the current study, day-old chicks were used to reduce the impact of individual differences on responses. Chicks were trained on a passive avoidance task and exposed to various auditory stimuli. Exposure to a complex rhythmic sequence for 1 min strongly facilitated chicks' long-term memory. The optimal time of presentation of the stimulus was between 10 min before and 20 min after training. Moreover, the enhancing effect was not generalized to the other auditory stimuli tested. It is suggested that this effect may be due to arousal because arousal hormones are critical to long-term memory formation. This study indicates that the temporal characteristics and type of stimulus may be important considerations when investigating the effects of auditory stimuli on cognitive functioning.  相似文献   
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Prior research on cognitive skill learning has shown that algorithmic and direct memory retrieval strategies are not executed in parallel if the algorithm entails a series of long-term memory (LTM) retrieval steps (as in the case, for example, of mental arithmetic). This phenomenon has been hypothesized to reflect a bottleneck in LTM retrieval processes that forces a strategy choice during an early stage of processing. Here, we investigate simple perceptual–motor algorithms that involve no memory retrieval steps, a largely unexplored case in which parallel strategy execution models remain viable. Pronounced strategy interference was again observed, albeit interference that was different in important respects from that observed for LTM retrieval algorithms. It appears that neither parallel nor choice models, as developed to date, are sufficient as a generalized theory of this skill learning phenomenon. Issues central to the development of a more comprehensive theory are discussed.  相似文献   
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Phoneme awareness is critical for literacy acquisition in English, but relatively little is known about the early development of phonological awareness in ESL (English as a second language) bilinguals when their two languages have different phonological structures. Using parallel tasks in English and Mandarin, we tracked the development of L1 (first language) and L2 (second language) syllable and phoneme awareness longitudinally in English-L1 and Mandarin-L1 prereaders (n=70, 4- and 5-year-olds) across three 6-month intervals. In English, the English-L1 children's performance was better in phoneme awareness at all three time points, but the Mandarin-L1 children's syllable awareness was equivalent to the English-L1 children's syllable awareness by Time 3. In Mandarin, the English-L1 children's phoneme awareness, but not their syllable awareness, was also significantly better than that of the Mandarin-L1 children at all three time points. Cross-lagged correlations revealed that only the English-L1 children applied their L1 syllable and phoneme awareness to their L2 (Mandarin) processing by Time 2 and that the Mandarin-L1 children seemed to require exposure to English (L2) before they developed phoneme awareness in either language. The data provide further evidence that phonological awareness is a language-general ability but that cross-language application depends on the similarity between the phonological structures of a child's L1 and L2. Implications for classroom teaching are briefly discussed.  相似文献   
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Bilateral administration of nitric oxide synthase inhibitors into the intermediate medial hyperstriatal (IMHV) region of the chick brain impairs memory formation for an avoidance task. The aim of the current study was to determine whether this effect was restricted to a particular location in the brain, and whether inhibition was equally effective in both hemispheres. White Leghorn x black Australorp chicks were administered 0.5 mM N(omega)-Nitro-L-arginine methyl ester bilaterally into the lobus parolfactorius (LPO), or unilaterally into the IMHV. Injections into the LPO between 5 min pre-training and 40 min post-training had no effect on retention. In contrast, unilateral injections into the IMHV impaired retention and memory loss occurred from 40 min post-training. The effective administration time was hemisphere-dependent, requiring left hemisphere administration around the time of training and right hemisphere administration between 15 and 25 min post-training. These data suggest that localized nitric oxide activity in each hemisphere of the chick brain is necessary for the consolidation of memory for this task.  相似文献   
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We propose a mechanism of how the desire to maintain friendships can intensify gender differences in educational choice. The required conditions for this mechanism would be that (1) adolescent males and females differ in their overall educational preferences, (2) wanting to stay close to friends motivates some adolescents to adjust their educational choice in line with their friends' choices, and (3) adolescents have a higher share of same-gender, than other-gender, friends. Study 1 confirmed that these criteria were met, and Study 2 found an association between friendship priority and gender typed field of study. In conclusion, adjusting educational choices in order to maintain friendships put adolescents at risk of compromising their true career interests, and also becomes an obstacle to a gender balanced labor market.  相似文献   
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