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151.
152.
The acetylcholinesterase reversible inhibitorN-octyl-1,2,3,4-tetrahydro-9-aminoacridine (THA-C8) is a new synthesized derivative of tacrine (THA) characterized by an alkyl chain in the molecular structure which ameliorates the penetrability of the compound into the central nervous system. THA-C8 (0.1–5 mg/kg) significantly reduced spontaneous locomotor activity in CD1 mice at a dose of 3 mg/kg. Moreover, THA-C8 (0.2–2 mg/kg) significantly improved shuttle-box avoidance acquisition at doses (0.25, 0.3, 1 mg/kg) not affecting locomotion and that are much lower than the doses reported to be effective for THA in animal models. From the data reported it seems that the new compound could be interesting for therapeutic purposes.  相似文献   
153.
This study was aimed at the examination of ‘mental construction’ in paradise fish by interactive learning, which is suggested as an alternative hypothesis for backward or second-order conditioning. Avoidance of goldfish was established in paradise fish by presenting a harmless goldfish (a novel stimulus) after an aversive event (mild electric shocks) in the dark compartment of a shuttle tank. It was found that this avoidance depended on context pre-exposure. Experiment 1 was designed to study the effect of mild shocks on shuttling activity in a familiar context. Experiment 2 aimed at establishing fear-conditioning to the goldfish in a higher-order conditioning paradigm. In the course of training, unpaired stimuli were presented in the dark compartment of the shuttle tank in such a manner that the presentation of mild shocks (20 mA) preceded the encounter with a harmless fish (goldfish). Experiment 3 demonstrated the role of context pre-exposure in interactive learning. Results indicate that (1) while 60 mA shocks resulted in avoidance of the dark compartment, the 20 mA mild shocks affected exploratory behaviour; (2) after pre-exposure to the training environment, paradise fish avoided the dark compartment containing goldfish provided that subjects had previously encountered mild, explorative shocks there; (3) this conditioned fear, a ‘mental construction’ of a potential danger, was proved to be transferable to another context and was consequently aimed specifically at the goldfish, a living being, rather than the training context; (4) the pre-exposure to the shuttle tank was an important part of this training procedure, that is, only subjects habituated to the shuttle tank avoided the goldfish. Results are discussed in the framework of the Interactive Learning Hypothesis, which has been developed as an ethological approach to a higher-order conditioning paradigm. Received: 15 January 1999 / Accepted after revision: 18 August 1999  相似文献   
154.
Analysis of 1998 statistics for individual performance in the PGA European Tour yielded significant differences between some shot-making skills (drive distance, total driving, greens in regulation, and sand saves) between the top 10 and bottom 10 money winners, replicating (with partially different results) a result found for the 1995 American PGA Tour by Engelhardt.  相似文献   
155.
156.
We investigate the emergence of iconicity, specifically a bouba‐kiki effect in miniature artificial languages under different functional constraints: when the languages are reproduced and when they are used communicatively. We ran transmission chains of (a) participant dyads who played an interactive communicative game and (b) individual participants who played a matched learning game. An analysis of the languages over six generations in an iterated learning experiment revealed that in the Communication condition, but not in the Reproduction condition, words for spiky shapes tend to be rated by naive judges as more spiky than the words for round shapes. This suggests that iconicity may not only be the outcome of innovations introduced by individuals, but, crucially, the result of interlocutor negotiation of new communicative conventions. We interpret our results as an illustration of cultural evolution by random mutation and selection (as opposed to by guided variation).  相似文献   
157.
Legal Audiences     
This paper approaches legal argumentation from a rhetorical perspective. It discusses the nature of the audiences that are (and should be) targeted by judges in the legal process. Judicial opinions reach diverse groups of people with very different attitudes and expectations: other judges, lawyers, litigants, concerned citizens, etc. One important way in which these groups differ is that some of them are more likely to be persuaded by legalistic, precedent or statute-based arguments, while others expect judges to decide on grounds of justice or equity. So, judges face the challenge of determining whether they should select particular groups for special attention, or whether they have alternative rhetorical means to approach the problem of audience diversity. One strategy that is likely to be recommended by rhetorical scholars is that judges should not try to accommodate the various preferences of their actual readership, but that they should rather invoke an idealized audience or some version of Chaïm Perelman’s universal audience. However, the paper tries to show that the universal audience is of limited value for a discussion about how judges ought to proceed in the face of audience diversity. In particular, the idea of a universal audience does not help judges to make the choice between a legalistic or an equity-based approach to legal decision-making. By showing that this is so, the paper also raises doubts about the common thought that to invoke the universal audience in law is to appeal to natural law (as distinct from written, positive law).  相似文献   
158.
The term Latino is often used to describe a largely diverse group of individuals living in the United States. This very broad term minimizes within-group differences due to race, ethnicity, class, country of origin and impact of immigration. We conducted a content analysis of 78 articles from peer reviewed journals in the fields of family therapy and family studies focused on Latinos, published from 2000 to May 2010, to challenge the Theoretical Myth of Sameness. We describe our evaluation and offer a culturally sensitive clinical and research approach with Latinos.  相似文献   
159.
Conventional wisdom holds that power holders act more in line with their dispositions than do people who lack power. Drawing on principles of construct accessibility, we propose that this is the case only when no alternative constructs are activated. In three experiments, we assessed participants' chronic dispositions and subsequently manipulated participants' degree of power. Participants then either were or were not primed with alternative (i.e., inaccessible or counterdispositional) constructs. When no alternatives were activated, the responses of power holders--perceptions of other people (Experiment 1), preferences for charitable donations (Experiment 2), and strategies in an economic game (Experiment 3)--were more in line with their chronically accessible constructs than were the responses of low-power participants. However, when alternatives had been activated, power holders' responses were no longer more congruent with their dispositions than were the responses of low-power participants. We propose a single mechanism according to which power increases reliance on accessible constructs--that is, constructs that easily come to mind-regardless of whether these constructs are chronically or temporarily accessible.  相似文献   
160.
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