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51.
We present some recent technical results of us on the incompleteness of classical analysis and then discuss our work on the Arnol'd decision problems for the stability of fixed points of dynamical systems.Partially supported by FAPESP and CNPq (Brazil, Philosophy Section).  相似文献   
52.
In rats, amygdala benzodiazepine-like immunoreactivity decreases by 29% immediately after the animals step down from the platform of an inhibitory avoidance apparatus and decreases by a further 45% immediately after they receive a training footshock. The decrease is attributable to a release of diazepam or diazepam-like molecules. The immediate post-training intraamygdala injection of the central benzodiazepine antagonist flumazenil (10 nmole/amygdala) causes memory facilitation, and that of the GABA-A agonist muscimol (0.005 to 0.5 nmole) causes retrograde amnesia. Pretraining ip flumazenil administration (2.0 and 5.0 mg/kg) attenuates the effect of post-training muscimol by a factor of at least 100. The higher dose of pretraining flumazenil also causes memory facilitation. The data suggest that post-training consolidation is down-regulated by a GABA-A mechanism in the amygdala modulated by endogenous benzodiazepines released during training and at the time of consolidation.  相似文献   
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As part of a continuous process to explore the factors that might weaken or corrupt traditional peer review, in this paper, we query the ethics, fairness and validity of the request, by editors, of authors to suggest peer reviewers during the submission process. One of the reasons for the current crisis in science pertains to a loss in trust as a result of a flawed peer review which is by nature biased unless it is open peer review. As we indicate, the fact that some editors and journals rely on authors’ suggestions in terms of who should peer review their paper already instills a potential way to abuse the trust of the submission and publishing system. An author-suggested peer reviewer choice might also tempt authors to seek reviewers who might be more receptive or sympathetic to the authors’ message or results, and thus favor the outcome of that paper. Authors should thus not be placed in such a potentially ethically compromising situation, especially as a mandatory condition for submission. However, the fact that they do not have an opt-out choice during the submission process—especially when using an online submission system that makes such a suggestion compulsory—may constitute a violation of authors’ rights.  相似文献   
55.
Person-centered care offers a promising way to manage clinicians’ conscientious objection to providing services they consider morally wrong. Health care centered on persons, rather than patients, recognizes clinicians and patients on the same stratum. The moral interests of clinicians, as persons, thus warrant as much consideration as those of other persons, including patients. Interconnected moral interests of clinicians, patients, and society construct the clinician as a socially embedded and integrated self, transcending the simplistic duality of private conscience versus public role expectations. In this milieu of blurred boundaries, person-centered care offers a constructive way to accommodate conscientious objection by clinicians. The constitutionally social nature of clinicians commits and enables them, through care mechanisms such as self-care, to optimize the quality of health care and protect the welfare of patients. To advance these conditions, it is recommended that the medical profession develop a person-centered culture of care, along with clinician virtues and skills for person-centered communication.  相似文献   
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The aim of the present study was to test if the nigrostriatal pathway is an essential component for a water maze cued task learning and if it works independently of the hippocampal memory system. This hypothesis was tested using an animal model of Parkinson's disease in which male Wistar rats were lesioned in the substantia nigra pars compacta (SNc) by the intranigral infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), thus causing a partial depletion of striatal dopamine. SNc-lesioned and sham-operated animals were implanted bilaterally with guide cannulae above the dorsal hippocampus in order to be tested after the administration of 0.4 microl 2% lidocaine or saline into this structure. The animals were tested in a spatial or in a cued version of the water maze, memory tasks previously reported to model hippocampal-dependent spatial/relational and striatal-dependent S-R learning, respectively. Hippocampal inactivation, but not SNc lesion, impaired learning and memory in the spatial version of the water maze. An opposite situation was observed with the cued version. No significant interaction was observed between the SNc lesion and hippocampal inactivation conditions affecting scores in the spatial or in the cued version of the water maze. These results suggest that the nigrostriatal pathway is an essential part of the memory system that processes S-R learning and that it works independently of the hippocampal memory system that processes spatial/relational memories.  相似文献   
58.
Schrödinger logics are logical systems in which the principle of identity is not true in general. The intuitive motivation for these logics is both Erwin Schrödinger's thesis (which has been advanced by other authors) that identity lacks sense for elementary particles of modern physics, and the way which physicists deal with this concept; normally, they understandidentity as meaningindistinguishability (agreemment with respect to attributes). Observing that these concepts are equivalent in classical logic and mathematics, which underly the usual physical theories, we present a higher-order logical system in which these concepts are systematically separated. A classical semantics for the system is presented and some philosophical related questions are mentioned. One of the main characteristics of our system is that Leibniz' Principle of the Identity of Indiscernibles cannot be derived. This fact is in accordance with some authors who maintain that quantum mechanics violates this principle. Furthermore, our system may be viewed as a way of making sense some of Schrödinger's logical intuitions about the nature of elementary particles.The authors very much would like to thank the anonymous referee for his quite interesting suggestions, which contributed significantly to improve the paper.Presented byJan Zygmunt;  相似文献   
59.
S. Jakowski introduced the discussive prepositional calculus D 2as a basis for a logic which could be used as underlying logic of inconsistent but nontrivial theories (see, for example, N. C. A. da Costa and L. Dubikajtis, On Jakowski's discussive logic, in Non-Classical Logic, Model Theory and Computability, A. I. Arruda, N. C. A da Costa and R. Chuaqui edts., North-Holland, Amsterdam, 1977, 37–56). D 2has afterwards been extended to a first-order predicate calculus and to a higher-order logic (cf. the quoted paper). In this paper we present a natural version of D 2, in the sense of Jakowski and Gentzen; as a consequence, we suggest a new formulation of the discussive predicate calculus (with equality). A semantics for the new calculus is also presented.  相似文献   
60.
It is shown that the notions of aggressive behavior as ‘intentional emission of noxious stimulation’ (Buss, 1961, 1963, 1966, 1971) and that of ‘injuriating goal response’ (Dollard, Doob, Miller, Mower and Sears, 1939) are identical. The usefulness of these theories to predict S's reaction to the reception of a given noxious stimulation is questioned. It is suggested that S's reactions to noxious stimulation may or may not be aggressive, depending on whether the noxious stimulation S receives is interpreted as being a behavior justified by the nom in the situation, or as reflecting an aggressive intent of O. It is hypothesized that the norms established in the situation depend on (i) victim's perception of the noxious stimulation received as being instrumental for O's goal attainment, (ii) victim's perception of the value of O's goal, and (iii) the value of victim's own goal. The establishment of norms regulating the exchange of noxious stimulation between Ss is operationalized in two experiments. Aggression, defined as an infringement of these norms, is measured. In Experiment I, participate 56 female students, and in Experiment 2, 80 male students. Subject is alternately victim (he performs a sensorimotor task and receives an electric shock) and aggressor (he shocks the other S). In Experiment I it is found that Ss counteraggress faster and more frequently if they interpret the shock received from the partner as an infringement of the norm. In Experiment 2, Ss do not counteraggress more frequently, but they do counteraggress faster and evaluate O more negatively. It is concluded that the results clearly contradict current positions and favor the authors' cognitive reformulation of the determinants of aggressive behavior.  相似文献   
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