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We consider two topological interpretations of the modal diamond—as the closure operator (C-semantics) and as the derived set operator (d-semantics). We call the logics arising from these interpretations C-logics and d-logics, respectively. We axiomatize a number of subclasses of the class of nodec spaces with respect to both semantics, and characterize exactly which of these classes are modally definable. It is demonstrated that the d-semantics is more expressive than the C-semantics. In particular, we show that the d-logics of the six classes of spaces considered in the paper are pairwise distinct, while the C-logics of some of them coincide. Mathematics Subject Classifications (2000): 03B45, 54G99. Presented by Michael Zakharyaschev  相似文献   
244.
Information obtained at interview from 1,646 parasuicide patients in 14 regions in 13 European countries participating in the WHO/EURO Multicentre Study on Suicidal Behaviour was used to study self-reported intentions involved in parasuicide. Comparisons were made across cultures, genders, and age groups. Although some statistically significant differences were found, the effect sizes were very small. The main finding from this study is thus that parasuicide patients in different countries tend to indicate that similar types of intentions are involved in their acts of parasuicide, and that the intentions do not vary greatly with gender or age. The hypothesis that rates of suicide and parasuicide vary between regions with the frequency with which suicidal intention is indicated by the patients was also tested, but was supported only for women and in relation to national suicide rates. The findings from this study are likely to be generalizable to other settings and have implications for clinical practice.  相似文献   
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Journal of Child and Family Studies - Non-suicidal self-injury (NSSI) is described as the intentional destruction of one’s own bodily tissue without lethal intent and is a common behavior...  相似文献   
246.
Response times (RTs) were measured in a postgrouping visual identification task. Shapes composed of multiple elements were distinguished by color, motion, orientation, and spatial frequency alone or in pairwise conjunctions. The largest amount of redundancy gain, requiring coactivation as revealed by a race model analysis, was obtained with color-motion conjunctions. In contrast, RTs for a pregrouping detection task using the same target shape as in the identification task, distinguished by color, motion, or a conjunction of these features, showed no evidence for coactivation. The results provide psychophysical evidence for coactivation of color and motion signals in cortical regions specialized for grouping and object identification, as opposed to separate processing of these features in cortical area V1, believed to limit performance in visual search and pregrouping detection.  相似文献   
247.
Leo Esakia  Benedikt L?we 《Studia Logica》2012,100(1-2):163-173
Hamkins and L?we proved that the modal logic of forcing is S4.2. In this paper, we consider its modal companion, the intermediate logic KC and relate it to the fatal Heyting algebra H ZFC of forcing persistent sentences. This Heyting algebra is equationally generic for the class of fatal Heyting algebras. Motivated by these results, we further analyse the class of fatal Heyting algebras.  相似文献   
248.
Our study sought to characterize mood disordered suicide ideators and attempters 50 years and older admitted to a psychiatric ward either for a recent suicide attempt or for ongoing suicidal ideation. We enrolled 50 patients with suicide ideation consecutively admitted to an inpatient department and 50 patients admitted for a suicide attempt made in the last 48 hours. Suicide attempters more frequently had low social support and an age of onset of mood disorder of 46 years and older, and less frequently had a history of suicidal behaviors in the family members and pharmacological treatment, despite the fact that the groups did not differ with regard to antidepressants prescribed. The groups were not distinguishable based on several variables assumed to be risk factors for suicide behavior, such as proximal life events and stressors or alcohol use disorders. In both samples, comorbidity with organic diseases, the presence of stressful life events in the past 12 months, and a diagnosis of major depression were frequently reported. In conclusion, the presence of low social support and the absence of a pharmacotherapy may increase suicidal behaviors in patients at risk.  相似文献   
249.
The association was examined between 98 third-grade pupils' expressed self-image scores and inferred self-image ratings from teachers. Significant self-other agreements were found with sexes combined. With sexes separated, significant self-other agreements were found for the 52 girls, but not for the 46 boys.  相似文献   
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