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141.
Evidence of learning and generalization of visual regularities in a newborn organism is provided in the present research. Domestic chicks have been trained to discriminate visual triplets of simultaneously presented shapes, implementing AAB versus ABA (Experiment 1), AAB versus ABB and AAB versus BAA (Experiment 2). Chicks distinguished pattern-following and pattern-violating novel test triplets in all comparisons, showing no preference for repetition-based patterns. The animals generalized to novel instances even when the patterns compared were not discriminable by the presence or absence of reduplicated elements or by symmetry (e.g., AAB vs. ABB). These findings represent the first evidence of learning and generalization of regularities at the onset of life in an animal model, revealing intriguing differences with respect to human newborns and infants. Extensive prior experience seems to be unnecessary to drive the process, suggesting that chicks are predisposed to detect patterns characterizing the visual world.  相似文献   
142.
143.
Gian Aldo Antonelli 《Synthese》1996,107(2):167-204
In this paper we argue that Revision Rules, introduced by Anil Gupta and Nuel Belnap as a tool for the analysis of the concept of truth, also provide a useful tool for defining computable functions. This also makes good on Gupta's and Belnap's claim that Revision Rules provide a general theory of definition, a claim for which they supply only the example of truth. In particular we show how Revision Rules arise naturally from relaxing and generalizing a classical construction due to Kleene, and indicate how they can be employed to reconstruct the class of the general recursive functions. We also point at how Revision Rules can be employed to access non-minimal fixed points of partially defined computing procedures.I thank Nuel Belnap, Rich Thomason, Ken Manders, and Jamie Tappenden for much helpful advice given while I was trying to get clear on the ideas presented here. I also thank two anonymous referees for helpful comments and criticisms on an earlier version of this paper.  相似文献   
144.
Aldo Ursini 《Studia Logica》1979,38(3):297-311
This paper treats a kind of a modal logic based on the intuitionistic propositional logic which arose from the provability predicate in the first order arithmetic. The semantics of this calculus is presented in both a relational and an algebraic way.Completeness theorems, existence of a characteristic model and of a characteristic frame, properties of FMP and FFP and decidability are proved.  相似文献   
145.
Two chromatically identical patterns, a diamond and a ladder, were shown on a computer touchscreen. Domestic hens were reinforced for pecking at the pattern that was the highest up on a grid that provided pictorial depth information, i.e. on the pattern that to a human appears as being the furthest away. Every tenth trial was a non-rewarded probe trial with the two patterns partially overlapping. In the absence of other cues depth stratification can occur on the basis of a minimization of interpolated occluding contours. In humans the diamond is usually perceived to be in front of the ladder because shorter interpolated contours are needed to account for the occlusive effect of the diamond on the ladder. The hens pecked more often at the ladder during the probe trials. The results suggest that the avian and mammalian visual systems operate along similar principles when dealing with the problem of solving occlusion indeterminacy in chromatically homogeneous patterns. Received: 26 March 1999 / Accepted after revision: 17 September 1999  相似文献   
146.
Clinical burnout is one of the leading causes of work absenteeism in high‐ and middle‐income countries. There is hence a great need for the identification of effective intervention strategies to increase return‐to‐work (RTW) in this population. This review aimed to assess the effectiveness of tertiary interventions for individuals with clinically significant burnout on RTW and psychological symptoms of exhaustion, depression and anxiety. Four electronic databases (Ovid MEDLINE, PsychINFO, PubMed and CINAHL Plus) were searched in April 2016 for randomized and non‐randomized controlled trials of tertiary interventions in clinical burnout. Article screening and data extraction were conducted independently by two reviewers. Pooled odds ratios (ORs) and hazard ratios (HRs) were estimated with random‐effects meta‐analyses. Eight articles met the inclusion criteria. There was some evidence of publication bias. Included trials were of variable methodological quality. A significant effect of tertiary interventions compared with treatment as usual or wait‐list controls on time until RTW was found, HR = 4.5, 95% confidence interval (CI) = 2.15–9.45; however, considerable heterogeneity was detected. The effect of tertiary interventions on full RTW was not significant, OR = 1.33, 95% CI = 0.59–2.98. No significant effects on psychological symptoms of exhaustion, depression or anxiety were observed. In conclusion, tertiary interventions for individuals with clinically significant burnout may be effective in facilitating RTW. Successful interventions incorporated advice from labor experts and enabled patients to initiate a workplace dialogue with their employers.  相似文献   
147.
Background  In the last 30 years, there has been little innovation in workstations. The desktop metaphor has become the standard user interface, with its pros (e.g., ease of learning) and cons (e.g., interaction constraints for skilled users, lack of context awareness). Objectives  In this paper, we present itsme, an Italian initiative to design the next-generation workstation. Interaction design is the basis of the project, as well as the involvement of a wide community of contributing users. Results  The early design phases of the project led to the definition of a new metaphor for personal computing, based on stories and venues. The metaphor is being adopted for the development of a novel front-end for the Linux operating system, aimed at fulfilling the needs and desires of knowledge workers.
Claudio ModeriniEmail: URL: http://www.itsme.it
  相似文献   
148.
Extraversion and Neuroticism are two fundamental dimensions of human personality that influence cognitive functioning in healthy subjects. Little is known about personality changes that may occur in patients with multiple sclerosis (MS) nor about, in particular, their neurofunctional basis. The aim of this study is to determine the impact of personality characteristics on brain activity in patients with MS. Eighteen patients with clinically definite relapsing-remitting MS without any evidence of psychiatric or cognitive disorders and thirteen healthy controls matched for age, gender and education were investigated using functional magnetic resonance imaging (fMRI) during the execution of an “n-back” task. No differences were detected on the behavioral tests between the two groups, although the MS patients had lower total IQ and showed a trend towards higher Extraversion and Neuroticism scores than did the controls. fMRI analyses demonstrated that Extraversion scores were positively associated with brain activity in the fronto-parietal network including the superior parietal lobule and dorsolateral prefrontal cortex in both groups during the high load condition of the n-back task. Given the overlapping neural systems found in the two groups, we suggest that the neural activity associated with specific personality dimension is a neurophysiological characteristic preserved in patients with MS at an early stage in the course of their disease.  相似文献   
149.
Several vertebrate species, including humans, following passive spatial disorientation appear to be able to reorient themselves by making use of the geometric shape of the environment (i.e., metric properties of surfaces and directional sense). In some circumstances, reliance on such purely geometric information can overcome the use of local featural cues (landmarks). The relative use of geometric and non-geometric information seems to depend upon, among other factors, the size of the experimental space. Evidence in non-human animals and in human infants for primacy in encoding either geometric or landmark information depending on the size of the environment is reviewed, together with possible theoretical accounts of this phenomenon.  相似文献   
150.
This study examined overall hopelessness, explored differences in various variables (e.g. burnout) between men reporting no/mild hopelessness and moderate/severe hopelessness, and scrutinized factors associated with hopelessness. The study design was cross-sectional, and the participants were 517 men randomly selected from the general population. About 12% of men reported moderate/severe hopelessness, and men with moderate/severe hopelessness were more often older, divorced/widowed, low educated, employed in blue-collar positions, on sick leave/other/unemployment/retirement, and financially strained. They also reported more depression, posttraumatic symptoms, and burnout. Only unemployment/retirement, depression, and posttraumatic symptoms were independently associated with an increased risk for moderate/severe hopelessness in the regression analysis, with unemployment and retirement as the most important factors. In conclusion, this study seems to corroborate previous findings and may provide new insights into men's experiences and predictors of hopelessness. More research into the predictors of hopelessness in men is warranted.  相似文献   
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