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161.
Raul Hakli  Sara Negri 《Synthese》2012,187(3):849-867
Various sources in the literature claim that the deduction theorem does not hold for normal modal or epistemic logic, whereas others present versions of the deduction theorem for several normal modal systems. It is shown here that the apparent problem arises from an objectionable notion of derivability from assumptions in an axiomatic system. When a traditional Hilbert-type system of axiomatic logic is generalized into a system for derivations from assumptions, the necessitation rule has to be modified in a way that restricts its use to cases in which the premiss does not depend on assumptions. This restriction is entirely analogous to the restriction of the rule of universal generalization of first-order logic. A necessitation rule with this restriction permits a proof of the deduction theorem in its usual formulation. Other suggestions presented in the literature to deal with the problem are reviewed, and the present solution is argued to be preferable to the other alternatives. A contraction- and cut-free sequent calculus equivalent to the Hilbert system for basic modal logic shows the standard failure argument untenable by proving the underivability of ${\square\,A}$ from A.  相似文献   
162.
This longitudinal study among ethnic migrants from Russia to Finland (N = 127) examined the relationships between anticipated and perceived discrimination, ethnic and national identities, and outgroup attitudes towards the national majority group. The study included one pre‐migration and two post‐migration assessments. First, associations between the variables studied were tested using a conventional autoregressive sample‐level modelling approach. Second, individual trajectories and the associations between the individual‐level changes in the variables included in the models were tested. Although there were no sample‐level effects over time, there were significant relationships between changes in discrimination and changes in identification and outgroup attitudes at the individual level. The results indicated that changes in perceived discrimination were not reflected in increased ethnic identification. However, participants who perceived higher levels of discrimination after migration than they anticipated before migration were, in the post‐migration stage, more likely to disidentify from and to increasingly show negative attitudes towards the national majority group. The study complements previous research by examining the identity and attitudinal reactions to perceived ethnic discrimination starting from the pre‐migration stage and highlights the value of incorporating both group and individual perspectives to the research on perceived discrimination. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
163.
Although children born preterm or low birth weight (PT LBW) are more likely to exhibit behavior problems compared to children born at term, developmental and family processes associated with these problems are unclear. We examined trajectories of maternal depressive symptoms in relation to toddler compliance and behavior problems in families with PT LBW infants. A total of 177 infants (93 boys, 84 girls) and their mothers enrolled in the study during the infant's NICU stay. Data were collected at five time points across 2 years. Assessments of maternal depressive symptoms were conducted at all time points, and toddler compliance and opposition to maternal requests and behavior problems were assessed at 2 years. Toddlers born earlier with more health problems to mothers whose depressive symptoms increased over time exhibited the most opposition to maternal requests during a cleanup task at 24 months, consistent with multiple risk models. Mothers with elevated depression symptoms reported more behavior problems in their toddlers. The study has implications for family‐based early intervention programs seeking to identify PT LBW infants at highest risk for problem behaviors.  相似文献   
164.
Socially disinhibited or indiscriminate behavior (IB) has traditionally been investigated using caregiver reports. More recently, an observational measure based on the Strange Situation Procedure (M. Ainsworth, M. Blehar, E. Waters, & S. Wall, 1978), the Rating of Infant and Stranger Engagement (RISE; C. Riley, A. Atlas‐Corbett, & K. Lyons‐Ruth, 2005), was validated in home‐reared at‐risk children. The present study aimed to validate the RISE in an institutionally reared sample using the caregiver report, to assess whether IB assessed with the RISE was elevated among the institutionalized children, and to explore potential risk factors associated with IB. The study was conducted among 74 institutionalized toddlers aged 11 to 30 months. Sociodemographic questionnaires were used to assess pre‐admission experiences, and aspects of institutional placement were coded from the children's files in the institution and staff's report. Institutionalized children displayed high frequencies of IB as assessed on the RISE, and this instrument was validated against caregiver report. Pre‐admission experiences of the institutionalized children in their biological families—namely, prenatal risk and maternal emotional neglect risk—predicted IB. Results suggest that the RISE is adequate to use among institutionally reared toddlers and point to aspects of the early familial environment that may be implicated in IB.  相似文献   
165.
Both negative and idealized maternal prenatal representations may constitute a risk for mother–infant interaction. This study analyzed the role of maternal prenatal representations and pre‐ to postnatal representational change in predicting mother–infant emotional availability (EA) among 51 drug‐abusing mothers and their infants who participated in either psychodynamic group therapy (PGT) or received psychosocial support (PSS) and among 50 nonusing comparison dyads. Maternal representations of her child, the child's father, her own mother, self‐as‐mother, and self‐as‐woman were measured during pregnancy and at 4 and 12 months' postpartum with the Interview of Maternal Representations (M. Ammaniti et al., 1992 ; M. Ammaniti, R. Tambelli, & P. Perucchini, 1998). EA was measured with the Emotional Availability Scales, fourth edition (Z. Biringen, 2008 ) at 4 and 12 months. The results showed that drug‐abusing mothers had more negative prenatal representations of the self‐as‐woman and of the child's father. Postnatally, PSS mothers tended to first idealize their child, but later to experience disillusionment of idealization. Both negative and idealized prenatal representations of the self‐as‐mother predicted mother–infant EA problems, but only among the PGT mothers. For all mothers, negative representational change was detrimental for the mother–infant EA whereas for drug‐abusing mothers, also increasing idealization from the prenatal period to the postnatal period was harmful. Clinicians working with drug‐abusing mothers should aim at supporting the development of a realistically positive view of motherhood.  相似文献   
166.
Underlying deficits in self‐regulation and sensory processing are seen in children with regulation disorders (RD) and might lead to emotional and behavioral problems as the child develops. However, little is known about the specific developmental course of RD. This follow‐up study was conducted to investigate the development of a clinical sample of RD children, diagnosed by means of the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood, Revised (DC:0–3R; ZERO TO THREE, 1994), toward specific psychopathology 4 to 10 years later based on parent‐ and teacher‐reports on the Child Behavior Checklist (T.M. Achenbach & L.A. Rescorla, 2007). Parental reports showed that 39 to 69% of children with RD had internalizing, externalizing, and total problems above borderline cutoffs, as compared to norm group data (16%). In addition, higher rates of affective, anxiety, attention deficit/hyperactivity, oppositional defiant, and conduct problems were reported. Analyses between RD subtypes showed significant differences on future attention problems and rule‐breaking behavior, wherein less favorable results were found for the Hypersensitive subtype Type A (fearful/cautious) in comparison to the sensory stimulation‐seeking/impulsive subtype. The current results indicate persistence of emotional and behavioral problems into middle childhood and adolescence in children with preschool RD diagnoses. More attention should be paid to differentiation of psychopathology in these children since developmental outcomes may differ between RD subtypes.  相似文献   
167.
Low-anger individuals are less reactive, both emotionally and behaviourally, to a large variety of situational primes to anger and aggression. Why this is so, from an affective processing perspective, has been largely conjectural. Four studies (total N=270) sought to link individual differences in anger to tendencies exhibited in basic affective processing tasks. On the basis of motivational factors and considerations, it was hypothesised that negative evaluations would differentially activate a psychological alarm system at low levels of anger, resulting in a pause that should be evident in the speed of making subsequent evaluations. Just such a pattern was evident in all studies. By contrast, high-anger individuals did not pause following their negative evaluations. In relation to this affective processing tendency, at least, dramatically different effects were observed among low- versus high-anger individuals. Implications for the personality-processing literature, theories of trait anger, and fast-acting regulatory processes are discussed.  相似文献   
168.
In the present study we elucidate the emotional and executive control interactions that might underlie optimism and pessimism. Participants completed a self-report measure of optimism/pessimism and performed an emotion faces categorisation task and an emotion n-back task in which they indicated whether each of a series of faces had the same or a different emotional expression (happy, sad, neutral) as the face presented two trials before. Trials were structured to measure latency to update emotional content in working memory (WM). More pessimistic individuals formed connections among positive stimuli, and broke connections among positive and sad stimuli, in WM more slowly than did less pessimistic individuals; levels of optimism/pessimism did not affect the rate with which individuals formed and broke connections among neutral representations in WM. It appears, therefore, that levels of pessimism are related to specific affective cognitive mechanisms in WM that may be involved in emotion regulation.  相似文献   
169.
The purpose of this article is to present the current status of the literature related to stress in clinical psychology trainees (CPTs), and to offer research directions for investigating stress in this population and ways to enhance self‐care in these individuals. The following conclusions emerge from the review: (1) CPTs are vulnerable to elevated stress; (2) undue stress can negatively impact CPTs' personal and professional functioning and, in turn, result in less than optimal standards of care for clients; (3) there is a dearth of studies on stress in this population and no published intervention studies; (4) incorporating self‐care strategies into clinical psychology training is recommended; and (5) “third‐wave” cognitive behaviour therapy stress management interventions have been efficacious in comparable populations. In view of the potential costs of elevated stress to trainees themselves and their clients, research on stress and stress management in this population is of a high priority. Broad research agendas are proposed for these two domains. Modifications to clinical training programmes to reduce trainee stress are required and should be evidence‐based and systematically revaluated.  相似文献   
170.
Background. A key learning outcome in problem‐solving domains is the development of procedural flexibility, where learners know multiple procedures and use them appropriately to solve a range of problems (e.g., Verschaffel, Luwel, Torbeyns, & Van Dooren, 2009 ). However, students often fail to become flexible problem solvers in mathematics. To support flexibility, teaching standards in many countries recommend that students be exposed to multiple procedures early in instruction and be encouraged to compare them. Aims. We experimentally evaluated this recommended instructional practice for supporting procedural flexibility during a classroom lesson, relative to two alternative conditions. The alternatives reflected the common instructional practice of delayed exposure to multiple procedures, either with or without comparison of procedures. Sample. Grade 8 students from two public schools (N= 198) were randomly assigned to condition. Students had not received prior instruction on multi‐step equation solving, which was the topic of our lessons. Method. Students learned about multi‐step equation solving under one of three conditions in math class for about 3 hr. They also completed a pre‐test, post‐test, and 1‐month‐retention test on their procedural knowledge, procedural flexibility, and conceptual knowledge of equation solving. Results. Novices who compared procedures immediately were more flexible problem solvers than those who did not, even on a 1‐month retention test. Although condition had limited direct impact on conceptual and procedural knowledge, greater flexibility was associated with greater knowledge of both types. Conclusions. Comparing procedures can support flexibility in novices and early introduction to multiple procedures may be one important reason.  相似文献   
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