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Population attributable risk (PAR) estimates have been used in suicide research to evaluate the impact of psychosocial and socioeconomic risk factors, including affective disorders, traumatic life events, and unemployment. A parallel concept of preventive fraction (PF), allowing for estimation of the impact of protective factors and effectiveness of preventive interventions, is practically unknown in suicidology. The study authors discuss the application of both concepts to suicide research and prevention, and review literature on the subject. Despite several methodological and conceptual limitations, both PAR and PF are valuable instruments to inform development and evaluation of suicide prevention programs.  相似文献   
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This paper describes approaches taken at the International Rehabilitation and Research Centre in Copenhagen to helping torture victims and their families cope with the exposure to and aftermath of torture.  相似文献   
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The most difficult problem that Leniewski came across in constructing his system of the foundations of mathematics was the problem of defining definitions, as he used to put it. He solved it to his satisfaction only when he had completed the formalization of his protothetic and ontology. By formalization of a deductive system one ought to understand in this context the statement, as precise and unambiguous as possible, of the conditions an expression has to satisfy if it is added to the system as a new thesis. Now, some protothetical theses, and some ontological ones, included in the respective systems, happen to be definitions. In the present essay I employ Leniewski's method of terminological explanations for the purpose of formalizing ukasiewicz's system of implicational calculus of propositions, which system, without having recourse to quantification, I first extended some time ago into a functionally complete system. This I achieved by allowing for a rule of implicational definitions, which enabled me to define any propositionforming functor for any finite number of propositional arguments.To the memory of Jerzy Supecki  相似文献   
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In the paper there are introduced and discussed the concepts of an indexed category with quantifications and a higher level indexed category to present an algebraic characterization of some version of Martin-Löf Type Theory. This characterization is given by specifying an additional equational structure of those indexed categories which are models of Martin-Löf Type Theory. One can consider the presented characterization as an essentially algebraic theory of categorical models of Martin-Löf Type Theory. The paper contains a construction of an indexed category with quantifications from terms and types of the language of Martin-Löf Type Theory given in the manner of Troelstra [11]. The paper contains also an inductive definition of a valuation of these terms and types in an indexed category with quantifications.  相似文献   
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Universality of generalized Alexandroff's cube plays essential role in theory of absolute retracts for the category of , -closure spaces. Alexandroff's cube. is an , -closure space generated by the family of all complete filters. in a lattice of all subsets of a set of power .Condition P(, , ) says that is a closure space of all , -filters in the lattice ( ), .Assuming that P (, , ) holds, in the paper [2], there are given sufficient conditions saying when an , -closure space is an absolute retract for the category of , -closure spaces (see Theorems 2.1 and 3.4 in [2]).It seems that, under assumption that P (, , ) holds, it will be possible to givean uniform characterization of absolute retracts for the category of , -closure-spaces.Except Lemma 3.1 from [1], there is no information when the condition P (, , ) holds or when it does not hold.The main result of this paper says, that there are examples of cardinal numbers, , , such that P (, , ) is not satisfied.Namely it is proved, using elementary properties of Lebesgue measure on the real line, that the condition P (, 1, 2 ) is not satisfied.Moreover it is shown that fulfillment of the condition is essential assumption in, Theorems 2.1 and 3.4 from [1] i.e. it cannot be eliminated.  相似文献   
8.
The main theorem says that a consequence operator is an effective part of the consequence operator for the classical prepositional calculus iff it is a consequence operator for a logic satisfying the compactness theorem, and in which every finitely axiomatizable theory is decidable.  相似文献   
9.
In the kibbutz today, there are no ideological or economic barriers to prevent a couple from deciding to divorce. Both husband and wife are assured continued economic security and equal opportunities for co-parenting, thus reducing fears of disruption in the daily contact with the children. In spite of these favorable circumstances, marital breakups in the kibbutz are less frequent than in the larger cities in Israel. In recent years, however, at a time when a stronger and more intensive family life has gained legitimacy within the kibbutz structure, there is a marked tendency toward a rise in the rate of divorce. In this article we analyze the possible causes of the variations in the frequency of divorce within the kibbutz framework.The authors express appreciation to Esther Mivtzari, a psychologist on the staff of the Kibbutz Child and Family Clinic and a member of the religious kibbutz Ein-Tzurim, for assistance in gathering data on divorce in the religious kibbitzum.  相似文献   
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This study focuses on Divorce-Prone individuals and the question of why some persons fail in one marriage after another. The authors studied 12 individuals who had each been divorced two or more times. They found that the cases fell into one of three broad and overlapping groups. The groups have been called the Self-Involved Narcissists, the Compliant Depressed, and the Casualties of Life's Vicissitudes. The individuals and the groups demonstrate a different etiology, different treatment problems, and a very different prognosis.  相似文献   
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