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221.
Although variability in behavioral traits within animal populations is well documented, the mechanisms maintaining that variability are still insufficiently known. In this study, we examined whether differences in thermal environment during egg incubation can permanently organize nonsocial behavior across different contexts and situations in a lizard species. We incubated eggs of the Yucatan banded gecko, Coleonyx elegans (Squamata: Gekkota: Eublepharidae) at 3 constant temperatures (26, 28, and 30 °C) and raised juveniles separately under the same conditions until adulthood. We then subjected them to 3 behavioral tests within 2 different contexts: an open-field test and a test of antipredator behavior (stressful context) as well as a test of feeding behavior (nonstressful context). Individuals of both sexes incubated at 30 °C were consistently less active and showed lower frequencies of several stereotypic behaviors in the stressful contexts than did individuals incubated at 26 and 28 °C. The test of feeding behavior revealed no significant effect of incubation temperature on geckos' behavior. Thus, our study demonstrates that developmental plasticity may play an important role in producing variability in stress-induced behavior in lizards.  相似文献   
222.
This study examined the temporal relationship between body evaluation and coital onset. In a population-based longitudinal study, 1449 Norwegian girls and boys between 12 and 15 years of age were followed at 4 waves over a span of 13 years. Body evaluation was used in order to predict coital onset besides romantic appeal and psychological problems. For girls early in adolescence, body evaluation did not influence the probability of coital onset during the first 2-year period. In the subsequent 5-year period, body dissatisfaction increased the probability for coital onset when romantic appeal was held constant. Body evaluation did not influence the odds of coital onset among boys. The findings imply that the pattern of association between body evaluation and coital onset differs according to the timing of coital onset for girls. Future research needs to distinguish body image from romantic appeal in relation to first time sexual experiences.  相似文献   
223.
Reports an error in "Longitudinal Changes in Behavioral Approach System Sensitivity and Brain Structures Involved in Reward Processing During Adolescence" by Sne?ana Uro?evi?, Paul Collins, Ryan Muetzel, Kelvin Lim and Monica Luciana (Developmental Psychology, Advanced Online Publication, Mar 5, 2012, np). Figure 2 was distorted in production. The correct version is presented in the erratum. (The following abstract of the original article appeared in record 2012-05404-001.) Adolescence is a period of radical normative changes and increased risk for substance use, mood disorders, and physical injury. Researchers have proposed that increases in reward sensitivity (i.e., sensitivity of the behavioral approach system [BAS]) and/or increases in reactivity to all emotional stimuli (i.e., reward and threat sensitivities) lead to these phenomena. The present study is the first longitudinal investigation of changes in reward (i.e., BAS) sensitivity in 9- to 23-year-olds across a 2-year follow-up. Support was found for increased reward sensitivity from early to late adolescence, and evidence was found for decline in the early 20s. This decline is combined with a decrease in left nucleus accumbens (Nacc) volume, a key structure for reward processing, from the late teens into the early 20s. Furthermore, we found longitudinal increases in sensitivity to reward to be predicted by individual differences in the Nacc and medial orbitofrontal cortex (OFC) volumes at baseline in this developmental sample. Similarly, increases in sensitivity to threat (i.e., behavioral inhibition system sensitivity) were qualified by sex, with only females participants experiencing this increase, and predicted by individual differences in lateral OFC volumes at baseline. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
224.
[Correction Notice: An Erratum for this article was reported in Vol 48(5) of Developmental Psychology (see record 2012-09244-001). Figure 2 was distorted in production. The correct version is presented in the erratum.] Adolescence is a period of radical normative changes and increased risk for substance use, mood disorders, and physical injury. Researchers have proposed that increases in reward sensitivity (i.e., sensitivity of the behavioral approach system [BAS]) and/or increases in reactivity to all emotional stimuli (i.e., reward and threat sensitivities) lead to these phenomena. The present study is the first longitudinal investigation of changes in reward (i.e., BAS) sensitivity in 9- to 23-year-olds across a 2-year follow-up. Support was found for increased reward sensitivity from early to late adolescence, and evidence was found for decline in the early 20s. This decline is combined with a decrease in left nucleus accumbens (Nacc) volume, a key structure for reward processing, from the late teens into the early 20s. Furthermore, we found longitudinal increases in sensitivity to reward to be predicted by individual differences in the Nacc and medial orbitofrontal cortex (OFC) volumes at baseline in this developmental sample. Similarly, increases in sensitivity to threat (i.e., behavioral inhibition system sensitivity) were qualified by sex, with only females participants experiencing this increase, and predicted by individual differences in lateral OFC volumes at baseline. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
225.
226.
Kosta Došen 《Studia Logica》1989,48(2):219-234
This paper presents duality results between categories of neighbourhood frames for modal logic and categories of modal algebras (i.e. Boolean algebras with an additional unary operation). These results extend results of Goldblatt and Thomason about categories of relational frames for modal logic.  相似文献   
227.
Summary Occlusion of one eye and functional hemidecortication by cortical spreading depression (CSD) were used to examine the relative importance of crossed and uncrossed visual projections for pattern discrimination learning in hooded and albino rats. Whereas functionally hemidecorticate albino rats were unable to learn in 200 trials a horizontal-vertical discrimination when using the eye contralateral to the depressed hemisphere, hooded rats needed under similar conditions three times as many trials to criterion (167) than when using opposite eye and hemisphere (59). An engram established in intact animals with both eyes could be retrieved in functionally hemidecorticate rats of both strains even with the eye ipsilateral to the intact hemicortex, but retraining required about twice as many trials as when using the contralateral eye. Retrieval of monocularly acquired engrams was less efficient under similar conditions. Pattern discrimination formed through crossed or uncrossed visual projections during monocular occlusion and contralateral or ipsilateral CSD was completely lateralized, since relearning with naive eye and hemisphere proceeded at the same rate as the original learning. On the contrary, a black-white discrimination trained with the eye contralateral to the depressed hemisphere could be partly retrieved by the untrained eye and hemisphere. It is concluded that the ipsilateral visual projection is more effective in hooded than in albino rats and that it can be more efficiently used for retrieval than for acquisition.This research was partly supported by the Foundations' Fund for Research in Psychiatry, Grant G69-453.  相似文献   
228.
Substructural logics are logics obtained from a sequent formulation of intuitionistic or classical logic by rejecting some structural rules. The substructural logics considered here are linear logic, relevant logic and BCK logic. It is proved that first-order variants of these logics with an intuitionistic negation can be embedded by modal translations into S40type extensions of these logics with a classical, involutive, negation. Related embeddings via translations like the double-negation translation are also considered. Embeddings into analogues of S4 are obtained with the help of cut climination for sequent formulations of our substructural logics and their modal extensions. These results are proved for systems with equality too.  相似文献   
229.
This is a review, with historical and critical comments, of a paper by I. E. Orlov from 1928, which gives the oldest known axiomatization of the implication-negation fragment of the relevant logic R. Orlov's paper also foreshadows the modal translation of systems with an intuitionistic negation into S4-type extensions of systems with a classical, involutive, negation. Orlov introduces the modal postulates of S4 before Becker, Lewis and Gödel. Orlov's work, which seems to be nearly completely ignored, is related to the contemporancous work on the axiomatization of intuitionistic logic.  相似文献   
230.
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