Decreasing Infant Mortality as a Global Demographic Change: A Challenge to Psychology

Decreasing infant mortality is taken up as a demographic phenomenon which constitutes one aspect of a broader conceptualization of “Global Change”. At the root of the global environmental problems faced today is the population issue. With sharp increases in the rates of infant and child survival, the question of what happens to those who survive assumes greater importance. With new policy shifts focusing on early childhood care and development, psychologists' expertise is now being called upon. Psychological knowledge is required especially in the cross-culturally valid conceptualization and assessment of human development. When made applicable to large numbers of children and parents, such knowledge can be used for detection and screening of risk cases and for establishing the environmental factors promoting psychosocial development.     

Algebraic logic for classical conjunction and disjunction

In this paper we study the relations between the fragment L of classical logic having just conjunction and disjunction and the variety D of distributive lattices, within the context of Algebraic Logic. We prove that these relations cannot be fully expressed either with the tools of Blok and Pigozzi's theory of algebraizable logics or with the use of reduced matrices for L. However, these relations can be naturally formulated when we introduce a new notion of model of a sequent calculus. When applied to a certain natural calculus for L, the resulting models are equivalent to a class of abstract logics (in the sense of Brown and Suszko) which we call distributive. Among other results, we prove that D is exactly the class of the algebraic reducts of the reduced models of L, that there is an embedding of the theories of L into the theories of the equational consequence (in the sense of Blok and Pigozzi) relative to D, and that for any algebra A of type (2,2) there is an isomorphism between the D-congruences of A and the models of L over A. In the second part of this paper (which will be published separately) we will also apply some results to give proofs with a logical flavour for several new or well-known lattice-theoretical properties.Dedicated to our master, Francesc d'A. Sales, on his 75th birthday     

A cut-free gentzen-type system for the logic of the weak law of excluded middle

The logic of the weak law of excluded middleKC _p is obtained by adding the formula A A as an axiom scheme to Heyting's intuitionistic logicH _p . A cut-free sequent calculus for this logic is given. As the consequences of the cut-elimination theorem, we get the decidability of the propositional part of this calculus, its separability, equality of the negationless fragments ofKC _p andH _p , interpolation theorems and so on. From the proof-theoretical point of view, the formulation presented in this paper makes clearer the relations betweenKC _p ,H _p , and the classical logic. In the end, an interpretation of classical propositional logic in the propositional part ofKC _p is given.     

Factor structure of items from the personality Adjective Check List in a sample of normal adolescents

We present the results of a principal-components analysis of the Personality Adjective Check List (PACL) at the item level, rather than at the scale level. The PACL was constructed by Strack (1987) to evaluate the personality scales proposed by Millon (1981). Data were obtained from a sample of normal adolescents. A scree test was applied to determine the number of factors to be extracted, and the retained factors were then rotated using a varimax procedure. Using the data from this second analysis, congruence coefficients were calculated by correlating the factor weights from the two analyses of men and women. Results reveal the existence in the whole sample of five unipolar personality factors, which we have called: Aggressive, Conscientious, Inhibited, Impulsive and Gregarious. These are not similar to those obtained from a sample of normal adults.     

Inferences by exclusion in the great apes: the effect of age and species

This study investigated the ability of chimpanzees, gorillas, orangutans, and bonobos to make inferences by exclusion using the procedure pioneered by Premack and Premack (Cognition 50:347–362, 1994) with chimpanzees. Thirty apes were presented with two different food items (banana vs. grape) on a platform and covered with identical containers. One of the items was removed from the container and placed between the two containers so that subjects could see it. After discarding this item, subjects could select between the two containers. In Experiment 1, apes preferentially selected the container that held the item that the experimenter had not discarded, especially if subjects saw the experimenter remove the item from the container (but without seeing the container empty). Experiment 3 in which the food was removed from one of the containers behind a barrier confirmed these results. In contrast, subjects performed at chance levels when a stimulus (colored plastic chip: Exp. 1; food item: Exp. 2 and Exp. 3) designated the item that had been removed. These results indicated that apes made inferences, not just learned to use a discriminative cue to avoid the empty container. Apes perceived and treated the item discarded by the experimenter as if it were the very one that had been hidden under the container. Results suggested a positive relationship between age and inferential ability independent of memory ability but no species differences.This contribution is part of the special issue “Animal Logics” (Watanabe and Huber 2006).     

Attitudes toward physical education and class preferences of Turkish adolescents in terms of school gender composition

The purpose of this study was to examine attitudes toward physical education (PE and PE class preferences of high school Turkish students in terms of school gender composition; 213 girls and 249 boys from coeducational public schools, and 196 girls and 210 boys from single-sex vocational schools participated in the study. The Attitudes Toward Physical Education Scale was administered and the results of 2 x 2 (Gender x School Type) ANOVA indicated that students in coeducational schools in general, and boys had more favorable attitudes. Additionally, chi-square analysis demonstrated significant differences in PE class preferences between students from single-sex and coeducational schools and between girls and boys.     

Unwilling versus unable: infants' understanding of intentional action

Infants experienced a female adult handling them toys. Sometimes, however, the transaction failed, either because the adult was in various ways unwilling to give the toy (e.g., she teased the child with it or played with it herself) or else because she was unable to give it (e.g., she accidentally dropped it). Infants at 9, 12, and 18 months of age reacted with more impatience (e.g., reaching, looking away) when the adult was unwilling to give them the toy than when she was simply unable to give it. Six-month-olds, in contrast, showed no evidence of this differentiation. Because infants' behavioral responses were appropriately adapted to different kinds of intentional actions, and because the adult's actions sometimes produced results that did not match her goal (when having accidents or failed attempts), these findings provide especially rich evidence that infants first begin to understand goal-directed action at around 9 months of age.     

Piagetian conservation of discrete quantities in bonobos (Pan paniscus), chimpanzees (Pan troglodytes), and orangutans (Pongo pygmaeus)

This study investigated whether physical discreteness helps apes to understand the concept of Piagetian conservation (i.e. the invariance of quantities). Subjects were four bonobos, three chimpanzees, and five orangutans. Apes were tested on their ability to conserve discrete/continuous quantities in an over-conservation procedure in which two unequal quantities of edible rewards underwent various transformations in front of subjects. Subjects were examined to determine whether they could track the larger quantity of reward after the transformation. Comparison between the two types of conservation revealed that tests with bonobos supported the discreteness hypothesis. Bonobos, but neither chimpanzees nor orangutans, performed significantly better with discrete quantities than with continuous ones. The results suggest that at least bonobos could benefit from the discreteness of stimuli in their acquisition of conservation skills.