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71.
The intra- and interspecific aggressive behavior of Formica polyctena, a species of the Formica rufa group, was analyzed and quantified both in the laboratory and in the field. This behavior was used as a potential taxonomic tool for gaining a better understanding of the phyletic relationships among the species within the group. No overt aggression was recorded toward members of the same species. To examine interspecific relationships, F. polyctena was first confronted with F. cunicularia, to ascertain its aggressiveness toward a distantly related species. All such encounters led immediately to overt and prolonged attacks with virtually no initial mutual inspection. This suggests that recognition of strangeness of the unrelated species is almost immediate in F. polyctena, as previously observed in F. lugubris and F. rufa toward the same antagonist. Subsequently, F. polyctena was contrasted with F. lugubris and F. rufa (also belonging to the F. rufa group) in order to compare these related species. Fierce attacks accompanied by all the elements of conflict behavior were observed in all encounters. Moreover, the degree of aggression in the field was higher than in laboratory-paired ants, possibly because of a territorial effect. These data and our previous and similar research indicate that the relationships between F. lugubris and F. rufa are closer than between these two species and F. polyctena. In considering different viewpoints on this problem, the validity of the aggression test is discussed and the opportunity to compare levels of aggressiveness among strictly sympatric samples of red wood ant species gathered from the same ecological environment are considered. 相似文献
72.
Francesco Berto Rohan French Graham Priest David Ripley 《Journal of Philosophical Logic》2018,47(4):693-713
A counterpossible conditional is a counterfactual with an impossible antecedent. Common sense delivers the view that some such conditionals are true, and some are false. In recent publications, Timothy Williamson has defended the view that all are true. In this paper we defend the common sense view against Williamson’s objections. 相似文献
73.
Francesco Maria Ferrari 《Axiomathes》2018,28(2):125-154
The main aim of this work is to evaluate whether Boolos’ semantics for second-order languages is model-theoretically equivalent to standard model-theoretic semantics. Such an equivalence result is, actually, directly proved in the “Appendix”. I argue that Boolos’ intent in developing such a semantics is not to avoid set-theoretic notions in favor of pluralities. It is, rather, to prevent that predicates, in the sense of functions, refer to classes of classes. Boolos’ formal semantics differs from a semantics of pluralities for Boolos’ plural reading of second-order quantifiers, for the notion of plurality is much more general, not only of that set, but also of class. In fact, by showing that a plurality is equivalent to sub-sets of a power set, the notion of plurality comes to suffer a loss of generality. Despite of this equivalence result, I maintain that Boolos’ formal semantics does not committ (directly) second-order languages (theories) to second-order entities (and to set theory), contrary to standard semantics. Further, such an equivalence result provides a rationale for many criticisms to Boolos’ formal semantics, in particular those by Resnik and Parsons against its alleged ontological innocence and on its Platonistic presupposition. The key set-theoretic notion involved in the equivalence proof is that of many-valued function. But, first, I will provide a clarification of the philosophical context and theoretical grounds of the genesis of Boolos’ formal semantics. 相似文献
74.
Papaleo F Silverman JL Aney J Tian Q Barkan CL Chadman KK Crawley JN 《Learning & memory (Cold Spring Harbor, N.Y.)》2011,18(8):534-544
BDNF regulates components of cognitive processes and has been implicated in psychiatric disorders. Here we report that genetic overexpression of the BDNF mature isoform (BDNF-tg) in female mice impaired working memory functions while sparing components of fear conditioning. BDNF-tg mice also displayed reduced breeding efficiency, higher anxiety-like scores, high self-grooming, impaired prepulse inhibition, and higher susceptibility to seizures when placed in a new empty cage, as compared with wild-type (WT) littermate controls. Control measures of general health, locomotor activity, motor coordination, depression-related behaviors, and sociability did not differ between genotypes. The present findings, indicating detrimental effects of life-long increased BDNF in mice, may inform human studies evaluating the role of BDNF functional genetic variations on cognitive abilities and vulnerability to psychiatric disorders. 相似文献
75.
We investigated the effect of subliminally presented happy or angry faces on evaluative judgments when the facial muscles of participants were free to mimic or blocked. We hypothesized and showed that subliminally presented happy expressions lead to more positive judgments of cartoons compared to angry expressions only when facial muscles were not blocked. These results reveal the influence of socially driven embodied processes on affective judgments and have also potential implications for phenomena such as emotional contagion. (PsycINFO Database Record (c) 2011 APA, all rights reserved). 相似文献
76.
Journal of Philosophical Logic - We propose a solution to the problem of logical omniscience in what we take to be its fundamental version: as concerning arbitrary agents and the knowledge attitude... 相似文献
77.
Guido Governatori Francesco Olivieri Antonino Rotolo Simone Scannapieco 《Journal of Philosophical Logic》2013,42(6):799-829
In this paper we propose an extension of Defeasible Logic to represent and compute different concepts of defeasible permission. In particular, we discuss some types of explicit permissive norms that work as exceptions to opposite obligations or encode permissive rights. Moreover, we show how strong permissions can be represented both with, and without introducing a new consequence relation for inferring conclusions from explicit permissive norms. Finally, we illustrate how a preference operator applicable to contrary-to-duty obligations can be combined with a new operator representing ordered sequences of strong permissions. The logical system is studied from a computational standpoint and is shown to have linear computational complexity. 相似文献
78.
79.
Di Nocera F Couyoumdjian A Ferlazzo F 《Quarterly journal of experimental psychology (2006)》2006,59(1):204-221
This paper introduces a perspective accounting for errors that may occur as a result of the human interaction with the three-dimensional (3D) space. Particularly, we are interested in errors that are caused by cognitively crossing the boundary between peripersonal and extrapersonal space. Several behavioural, neurophysiological, and neuropsychological perspectives are reviewed in order to develop the theoretical framework on which our ideas are founded. We argue that cognitively crossing the boundary implies switching from one frame of reference to another, which, as a consequence, implies specific costs. The results of five experiments (overall involving 76 participants) support our hypothesis, suggesting the existence of different action-oriented spatial frames of reference. 相似文献
80.
Across three experiments, participants made speeded elevation discrimination responses to vibrotactile targets presented to
the thumb (held in a lower position) or the index finger (upper position) of either hand, while simultaneously trying to ignore
visual distractors presented independently from either the same or a different elevation. Performance on the vibrotactile
elevation discrimination task was slower and less accurate when the visual distractor was incongruent with the elevation of
the vibrotactile target (e.g., a lower light during the presentation of an upper vibrotactile target to the index finger) than when they were congruent, showing that people cannot completely ignore vision
when selectively attending to vibrotactile information. We investigated the attentional, temporal, and spatial modulation
of these cross-modal congruency effects by manipulating the direction of endogenous tactile spatial attention, the stimulus
onset asynchrony between target and distractor, and the spatial separation between the vibrotactile target, any visual distractors,
and the participant’s two hands within and across hemifields. Our results provide new insights into the spatiotemporal modulation
of crossmodal congruency effects and highlight the utility of this paradigm for investigating the contributions of visual,
tactile, and proprioceptive inputs to the multisensory representation of peripersonal space. 相似文献