bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychophysiological correlates of empathy and prosocial behaviors in preschool children with behavior problems
Authors: Zahn-Waxler Carolyn , Cole Pamela M. , Welsh Jean Darby , Fox Nathan A.
Published: March 2009

This study focused on empathic and prosocial orientations in preschool children who vary in externalizing problems. Children were categorized as low, moderate, or high risk for developing disruptive behavior disorders, depending on severity of current behavior problems. Hypothetical and real encounters with others in distress were used to examine children's affect, behavior, autonomic activity, and social cognitions. When children witnessed someone in distress, empathic concern and prosocial behaviors were present at similar levels for all risk groups. However, moderate and high-risk children were less able than low-risk children to remain positively engaged with distress victims. Girls showed more prosocial behavior than boys, and boys showed more anger than girls. During sadness mood inductions to assess autonomic activity, risk groups did not differ on heart rate or vagal tone. Girls showed higher skin conductance than boys, with high-risk girls showing the highest levels. Higher heart rate (and heart rate deceleration) predicted empathic concern and prosocial behavior, whereas lower heart rate was associated with aggression and avoidance, irrespective of risk. Although biological correlates of emotions and behaviors that reflect caring versus indifference to others' distress are identified, they do not support an early direct link to externalizing psychopathologies.
Vagal tone protects children from marital conflict
Authors: Katz Lynn Fainsilber , Gottman John M.
Published: March 2009

In a previous article we reported linkages between marital hostility and children's externalizing behavior problems (Katz & Gottman, 1993). In this paper we examined whether individual differences in children's ability to regulate emotion (as indexed by vagal tone, a physiological measure of parasympathetic nervous system activity) could buffer children from the deleterious effects of marital hostility. Observational data was collected on 56 families during marital interaction when the children were 5 years-old. Baseline recordings of children's cardiac interbeat interval were also obtained for computations of vagal tone. Teacher ratings of children's behavior problems were obtained 3 years later when the children were on average 8 years old. Results indicated that children with low vagal tone showed a strong link between the amount of marital hostility displayed by their parents and subsequent displays of children's externalizing behavior. There was no relationship between marital hostility and children's externalizing for children with high vagal tone, suggesting that high vagal tone can buffer children from the negative effects of marital hostility.
Self-competence and emotional understanding in high-functioning children with autism
Authors: Capps Lisa , Sigman Marian , Yirmiya Nurit
Published: March 2009

This study examined the relationships between perceived self-competence, intellectual ability, emotional understanding, and parent report of social adaptation in 18 nonretarded children with autism. Children who perceived themselves as less socially competent demonstrated stronger intellectual capabilities, greater understanding of others' emotional experiences, and were better able to access their own emotional experiences than were those who perceived themselves as more socially competent. According to their parents, children who reported less social competence also displayed more socially adaptive behavior, and expressed more interest and less sadness and fear than did those who reported greater social competence. Discussion focuses on potential effects of this heightened capacity for emotional understanding on self-esteem and implications for intervention with highly intelligent persons with autism.
Discrepancies between self- and other-report of psychiatric symptomatology: Effects of dismissing attachment strategies
Authors: Dozier Mary , Lee Spring W.
Published: March 2009

This study examined the relationship between psychiatric symptomatology and the representations of attachment relationships held by adults with serious psychopathological disorders. Psychiatric symtomatology was assessed by self-report and three sets of expert ratings. Seventy-six persons with serious psychopathological disorders were included as participants. As expected, persons relying on hyperactivating strategies of attachment reported generally more psychiatric symptoms than did those relying on deactivating strategies of attachment. However, the three sets of experts rated persons relying on deactivating strategies as more symptomatic than others. More specifically, interviewers who conducted Quality of Life Interviews rated dismissing subjects as exhibiting looser thinking than others. Interviewers who conducted Attachment Interviews rated dismissing subjects as experiencing more delusions, hallucinations, and suspiciousness, and case managers rated dismissing subjects as generally more psychotic. These findings suggest that, although greater preoccupation with attachment issues is associated with more acknowledgment of distress generally and symptoms specifically, greater reliance on deactivating strategies may be associated with greater symptomatology observed by others.
The first two years of school: Teacher-child relationships and deflections in children's classroom adjustment
Authors: Pianta Robert C. , Steinberg Michael S. , Rollins Kristin B.
Published: March 2009

Teacher reports of children's competence and problem behaviors are an important source of information on psychopathology. The school context is also an agent of developmental change. This study examines teacherchild relationships and deflections in child adjustment over the school-entry to grade 2 period in 436 children. The Student-Teacher Relationship Scale (STRS) was related to two indices of deflections in predicted child adjustment: (a) residual scores obtained from regressing teacher reports from grade 1 on kindergarten teacher reports, and (b) false positive predictions of retention or referral for special education in the K-l period.

Children with whom kindergarten teachers reported a positive relationship were rated in spring of grade I as better adjusted than was predicted on the basis of identical ratings from the fall of the kindergarten year; the converse was also true. False-positive retention/referral predictions had more positive relationships with kindergarten teachers than did true positives. A second set of analyses examined second grade teacher ratings of child adjustment and child-teacher relationships in two groups of children with different child-teacher relationship histories in kindergarten. Children with warm, close, communicative relationships with kindergarten teachers were better adjusted and had more positive child-teacher relationships in second grade than those with angry, dependent child-teacher relationships in kindergarten. Results supported the view that children's relationships with teachers are an important component of adaptation in school, and that they can play a role in deflecting the course of development in the school context.
A Vygotskian critique of self-instructional training
Authors: Diaz Rafael M. , Berk Laura E.
Published: March 2009

Self-instructional training, a widely used intervention for treating the learning and behavioral difficulties of impulsive, attention deficit-hyperactivity disordered, and learning disabled children, has repeatedly failed to promote self-control or improve academic performance. In light of this failure, we critically examine four assumptions underlying self-instructional training: (a) children with learning and behavior problems show a lack and/or deficient use of self-regulatory private speech; (b) modeling of self-verbalizations will increase children's spontaneous production of private speech; (c) speech and action are intrinsically coordinated; and (d) internalization refers to subvocalization of private speech. We argue that self-instructional training interventions need to be thoroughly grounded in Soviet developmental theory of verbal self-regulation and in systematic research on the social origins and development of children's private speech. A new research agenda is suggested.
Attention: Prenatal alcohol and continuities of vigilance and attentional problems from 4 through 14 years
Authors: Streissguth Ann P. , Bookstein Fred L. , Sampson Paul D. , Barr Helen M.
Published: March 2009

This study examined the longitudinal components of vigilance performance and attentional behaviors across the ages of 4, 7, and 14 years of life as they relate to prenatal alcohol exposure assessed by maternal self-report in midpregnancy for a cohort of 512 children. The vigilance score most salient for prenatal alcohol across this 10-year developmental period was Standard Deviation of Reaction Time (SDRT). Also salient were False Alarms (FA) on the AX task, impulsive errors reflecting difficulty in withholding a response. All 19 of the children with poorest scores on a Vigilance Latent Variable (LV) at 14 years had scored low on a similarly-defined Vigilance LV at age 7 years. Cross-lagged correlations revealed that the 7-year Vigilance LV not only predicted second-grade teacher ratings of attention a year later (r= – .38), but also predicted fourth-fifth-grade teacher ratings of attention (r= – .36). These data reveal considerable consistency across time in the impact of prenatal alcohol on child/adolescent vigilance performance and attention between 4 and 14 years of age.
Maternal reports of child behavior problems and personal distress as predictors of dysfunctional parenting
Authors: Dumas Jean E. , Wekerle Christine
Published: March 2009

A community sample of 96 mother-child dyads participated in a study evaluating the extent to which directly observed differences in maternal parenting behavior could be predicted on the basis of both global and proximal maternal reports of child behavior problems and personal distress. To allow for simultaneous testing of a set of relations and make tentative causal inferences, a structural equation modeling approach was used. When the analysis was conducted on the entire sample, results indicated that global and to a lesser extent proximal measures of child behavior problems and personal distress made modest contributions to dysfunctional parenting, with neither child behavior problems or personal distress playing a more important role than the other. When the sample was divided into low (n = 54) and high (n = 42) socioeconomic disadvantage (SED) families, a different picture emerged. In low disadvantage families, parenting was most strongly predicted by mothers' proximal reports of their children's behavior; whereas in high disadvantage families, parenting was best predicted by mothers' proximal reports of their own personal distress. Results are interpreted in light of Wahler and Dumas' (1989) attentional hypothesis. It suggests that mothers who do not experience chronic sources of distress (such as SED) attend and respond to their children's behavior in a fairl accurate and consistent manner, but that mothers who experience chronic distress are unable to attend effectively to their children, responding to them often in light of the many stressors to which they are exposed, rather than in light of the children's actual behavior.
Childhood internalizing problems: Prediction from kindergarten, effect of maternal overprotectiveness, and sex differences
Authors: Bowen François , Vitaro Frank , Kerr Margaret , Pelletier Daniel
Published: March 2009

Research on the development of childhood internalizing problems has largely failed to consider that there may be different developmental paths for boys and girls. Additionally, studies have begun with elementary school children who are well beyond their first social experiences. This study follows 144 boys and 125 girls from kindergarten (for most children the time of first social experiences) to fifth grade. We identify the best predictors of fifth grade internalizing problems from kindergarten measure of anxiety-withdrawal, shyness, adaptability, and popularity. We also test whether maternal overprotectiveness moderates the link between kindergarten predictors and fifth-grade internalizing problems. Throughout, we consider boys and girls separately. Peer-rated unpopularity was the best predictor of later problems for both boys and girls, followed by peer-rated shyness for boys and teacher-rated anxiety-withdrawal for girls. Maternal overprotectiveness was more important for boys than girls. For boys overprotectiveness reduced the predictive link between some kindergarten variables and some fifth-grade outcomes; for girls overprotectiveness did not significantly moderate the predictive link. We discuss the advantages of different perspectives (peers, teachers, and mothers) for predicting internalizing problems. We also discuss the roles of early temperament, early social experience, and maternal overprotectiveness versus close temporal experience in developing internalizing problems.
Differences in mothers' and fathers' relationships with siblings: Links with children's behavior problems
Authors: Stocker Clare M.
Published: March 2009

Differences in mothers' and fathers' relationships with siblings and children's behavior problems were studied in a sample of 63 8-year-olds and their families. Mothers and fathers independently provided information about their relationships with siblings, and mothers rated children's adjustment and temperament. Children whose relationships with mothers and fathers were more conflictual and less close than their siblings' relationships had more emotional temperaments and more behavior problems than did other children in the sample. Mothers' and fathers' differential relationships with children were examined in combination. Children had the fewest behavior problems if both parents were closer to them than to their sibling, and they had the most behavior problems if both parents were closer to their sibling than to them. In families in which the mother was closer to one sibling and the father was closer to the other sibling, children had adjustment outcomes that fell in between the other two groups but did not differ significantly from them.
Maternal differential treatment of siblings and children's behavioral problems: A longitudinal study
Authors: McGuire Shirley , Dunn Judy , Plomin Robert
Published: March 2009

Researchers have examined links between maternal differential treatment of siblings and children's adjustment; however, little is known about the longitudinal nature of these associations. The goal of this study was to examine the relationship between maternal differential treatment of the siblings, direct parenting of older siblings, and older siblings' behavior problems across middle childhood. Eighty-two families were interviewed twice in their homes when the siblings averaged 4.7 and 7.7 years of age and, again when they averaged 7.9 and 10.5 years of age. Mothers completed questionnaires about parenting and older siblings' adjustment during the summer after the older siblings' 7th and 11th birthdays. Teachers completed questionnaires about the older siblings' adjustment and returned them through the mail. There was significant stability in the mothers' reports of differential treatment and significant associations between mothers' reports of maternal differential discipline and differential attention and mothers' and teachers' reports of older siblings' externalizing problems across time. Direct parenting measures were not correlated with differential treatment or older siblings' behavior problems across time.
Aggression, depression, and stressful life events predicting peer rejection in children
Authors: Little Stephanie A. , Garber Judy
Published: March 2009

This short-term prospective study examined the contribution of aggression and depression, stressful life events, and their interactions to the prediction of peer rejection. Subjects were 497 fifth- and sixth-grade children who completed questionnaires at two time points separated by approximately 3 months. Levels of peer rejection and aggression were assessed by peer nominations; level of depressive symptoms and number of stressful life events were measured by self-report questionnaires. Controlling for sex and baseline level of peer rejection, aggression directly predicted peer rejection. In contrast, depressive symptoms interacted with life stress to predict peer rejection. Examination of the Depression × Stress interaction revealed that depressive symptoms in children who had experienced high levels of life stress were not associated with increased levels of peer rejection, whereas depressive symptoms in children with low levels of stress were predictive of subsequent peer rejection. Several interpretations of these findings and directions for future research are suggested.
The regulation of sleep and arousal: Development and psychopathology
Authors: Dahl Ronald E.
Published: March 2009

Throughout early development, a child spends more time asleep than in any waking activity. Yet, the specific role of sleep in brain maturation is a complete mystery. In this article, the developmental psychobiology of sleep regulation is conceptualized within the context of close links to the control of arousal, affect, and attention. The interactions among these systems are considered from an ontogenetic and evolutionary biological perspective. A model is proposed for the development of sleep and arousal regulation with the following major tenets:

1. Sleep and vigilance represent opponent processes in a larger system of arousal regulation.

2. The regulation of sleep, arousal, affect, and attention overlap in physiological, neuroanatomical, clinical, and developmental domains.

3. Complex interactions among these regulatory systems are modulated and integrated in regions of the prefrontal cortex (PFC).

4. Changes at the level of PFC underlie maturational shifts in the relative balance across these regulatory systems (such as decreases in the depth/length of sleep and increased capacity for vigilance and attention), which occur with normal development.

5. The effects of sleep deprivation (including alterations in attention, emotions, and goal-directed behaviors) also involve changes at the level of PFC integration across regulatory systems.

This model is then discussed in the context of developmental pathology in the control of affect and attention, with an emphasis on sleep changes in depression.
Physiological regulation in high-risk infants: A model for assessment and potential intervention
Authors: Porges Stephen W.
Published: March 2009

The model presented identifies the importance of neural regulation of autonomic state as an antecedent substrate for emotional, cognitive, and behavioral regulation. It is proposed that individual differences in neural regulation of autonomic state are related to normal and abnormal development. Establishing nervous system regulation of autonomic state is the infant's initial task of self-regulation. Survival for the high-risk infant is based primarily on physiological self-regulation. Although the methods described focus on the high-risk neonate, the model provides insight into normal development and may be generalized to the study of older children and adults with behavioral and psychological problems. Moreover, the model may contribute to assessment and intervention strategics for normal and abnormal development.
Emotional security as a regulatory process in normal development and the development of psychopathology
Authors: Cummings E. Mark , Davies Patrick
Published: March 2009

Emotional security is a central concept in many accounts of normal development and the development of psychopathology. However, the construct has rarely been subject to precise explication, and the conceptualization of emotional security as deriving from qualities of family functioning as a whole requires development. Emotional security as a regulatory system is defined and related to current approaches to emotions as regulatory processes. Although our model is built upon attachment theory, the emphasis is shifted from the evolutionary/ethological origins of attachment theory to the regulation of emotional well being and security as a goal in itself. Emotional security is conceptualized from a contextualistic perspective, emphasizing the interplay between socioemotional and biological processes. Felt-security as a goal is defined from an organizational perspective, reflecting the entire pattern of the individual's reactions to events in relation to emotional security as a goal, as opposed to simply those reactions that are “conscious” or reported as “feelings.” Component regulatory systems are specified (e.g., processes of emotion regulation, regulation of exposure to family affect), with illustrations centering on the impact of marital and parent-child relations on children's security.
The double-edged sword: Emotional regulation for children at risk
Authors: Thompson Ross A. , Calkins Susan D.
Published: March 2009

The capacity to manage emotion is based on the growth of self-regulatory capacities in the early years, but is also affected by situational demands, influences from other people, and the child's goals for regulating emotion in a particular setting. For most children growing up in supportive contexts, the growth of emotional regulation is associated with enhanced psychosocial well-being and socioemotional competence. But for children who are at risk for the development of psychopathology owing to environmental stresses or intrinsic vulnerability (or their interaction), emotional regulation often entails inherent trade-offs that make nonoptimal strategics of managing emotion expectable, perhaps inevitable, in a context of difficult environmental demands and conflicting emotional goals. This analysis discusses how emotional regulation in children at risk may simultaneously foster both resiliency and vulnerability by considering how emotion is managed when children (a) are living with a parent who is depressed, (b) witness or experience domestic violence, or (c) are temperamentally inhibited when encountering novel challenges. In each case, the child's efforts to manage emotion may simultaneously buffer against certain stresses while also enhancing the child's vulnerability to other risks and demands. This double-edged sword of emotional regulation in conditions of risk for children cautions against using “optimal” emotional regulation as an evaluative standard for such children or assuming that emotional regulation necessarily improves psychosocial well-being. It also suggests how the study of emotional regulation must consider the goals for regulating emotion and the contexts in which those goals are sought.
The connection of observed hostile family conflict to adolescents' developing autonomy and relatedness with parents
Authors: Allen Joseph P. , Hauser Stuart T. , O'Connor Thomas G. , Bell Kathy L. , Eickholt Charlene
Published: March 2009

This study examined the link between hostile conflict in families with adolescents and adolescents' efforts to establish autonomy and relatedness in interactions with parents in both normal and psychiatrically impaired groups. Longitudinal, observational data were obtained by coding family interaction tasks involving 53 adolescents and their two parents at age 14 and age 16 years. Measures were obtained for hostile adolescent-parent conflict, hostile marital conflict, and indices of adolescents' success or difficultly in establishing autonomy and relatedness in interactions with parents. Relative increases in adolescent-parent hostile conflict from age 14 to 16 years were predicted by adolescents' behaviors actively undermining autonomy in disagreements with parents at age 14 years. Hostile marital conflict observed by the adolescent at age 14 years predicted adolescent withdrawal from the hostile parent over time, a prediction that was not mediated by observed parenting behaviors. Difficulties in establishing autonomy and relatedness were linked to prior history of psychiatric difficulty. A developmental view of conflict as both reflecting and predicting difficulties in adolescents' establishing autonomy and relatedness in interactions with parents is proposed.
Slowed orienting of covert visual-spatial attention in autism: Specific deficits associated with cerebellar and parietal abnormality
Authors: Townsend Jeanne , Courchesne Eric , Egaas Brian
Published: March 2009

The most commonly reported finding from structural brain studies in autism is abnormality of the cerebellum. Autopsy and magnetic resonance imaging (MR) studies from nine independent research groups have found developmental abnormality of the cerebellar vermis or hemispheres in the majority of the more than 240 subjects with autism who were studied. We reported previously that patients with autism and those with acquired damage to the cerebellum were slow to shift attention between and within sensory modalities. In this study, we found that patients with autism who come from a group with significant cerebellar abnormality were also slow to orient attention in space.

A subgroup of these patients who have additional or corollary parietal abnormality, like previously studied patients with acquired parietal damage, were also slow to detect and respond to information outside an attended location. Posner, Walker, Friedrich, and Rafal (1984) showed that patients with parietal lesions were slow to respond to contralesional information if they were attending an ipsilesional location. This study has replicated that finding in patients with autism who have developmental bilateral parietal abnormality, and found a strong correlation between the attentional deficits and the amount of neuroanatomic parietal abnormality in these patients. This is the first time in the study of autism that there is evidence for a statistically significant association of the size of a specific brain structural abnormality with a specific behavioral deficit.

These findings illustrate that in autism different patterns of underlying brain pathology may result in different patterns of functional deficits. In conjunction with previous studies of patients with acquired lesions, these data have implications for the brain bases of normal attention. The cerebellum may affect the speed with which attentional resources can be activated, while the parietal cortex affects the ability to use those resources for efficient information processing at locations outside an attended focus. Deficits in the speed and efficiency with which neural activity can be modulated to facilitate processing can clearly influence cognitive function. Such deficits may contribute to the behavioral disabilities that characterize autism.
Premorbid competence, thought-action orientation, and outcome in psychiatric patients with mild mental retardation
Authors: Glick Marion , Zigler Edward
Published: March 2009

In a sample of 112 psychiatric inpatients with mild mental retardation, lower premorbid social competence was significantly related to symptom expression in action compared to thought. Both of these variables were correlated with length of current hospitalization. Premorbid social competence and thought-action orientation have been major variables in developmental research on psychopathology in patients without mental retardation. These results indicate that these variables can be applied to differentiate developmental level among inpatients with mild mental retardation and that these developmental distinctions are related to other clinical variables, as has been found for inpatients without mental retardation. The findings also attest to the heterogeneity in developmental level among inpatients with mild mental retardation.
Developmental pathways in depression: Multiple meanings, antecedents, and endpoints
Authors: Harrington Richard , Rutter Michael , Fombonne Eric
Published: March 2009

This article presents an overview of work conducted at the Institute of Psychiatry over the past 30 years on childhood depression. The work began with the basic question of definition and measurement. Epidemiological studies showed that depressive symptoms were quite common in children and were a good, if nonspecific, indicator of psychological disturbance. Further work in both epidemiological and clinical samples provided some evidence for the validity of a depressive syndrome. However, this work also showed that these depressive syndromes represented a heterogeneous group of phenomena. The validity of major depressive disorder in children was therefore tested further in longitudinal and family-genetic studies. These studies supported the validity of the concept but confirmed that there was heterogeneity in respect to both developmental stage at the time of onset and comorbidity with conduct disorder. We concluded that there are probably several different kinds of depressive syndromes in children. Some are strongly linked with depressive disorders in adulthood, but others are probably better conceptualized as part of another psychopathological problem altogether.
Adult mental health and social outcomes of adolescent girls with depression and conduct disorder
Authors: Bardone Anna M. , Moffitt Terrie E. , Caspi Avshalom , Dickson Nigel , Silva Phil A.
Published: March 2009

Follow-up studies of adolescent depression and conduct disorder have pointed to homotypic continuity, but less information exists about outcomes beyond mental disorders and about the extent to which adolescents with different disorders experience different versus similar difficulties during the transition to adulthood. We assessed the continuity of adolescent disorder by following girls in a complete birth cohort who at age 15 were depressed (n = 27), conduct disordered (n = 37), or without a mental health disorder (n = 341) into young adulthood (age 21) to identify their outcomes in three domains: mental health and illegal behavior, human capital, and relationship and family formation. We found homotypic continuity; in general, depressed girls became depressed women and conduct disordered girls developed antisocial personality disorder symptoms by age 21. Conduct disorder exclusively predicted at age 21: antisocial personality disorder, substance dependence, illegal behavior, dependence on multiple welfare sources, early home leaving, multiple cohabitation partners, and physical partner violence. Depression exclusively predicted depression at age 21. Examples of equifinality (where alternate pathways lead to the same outcome) surfaced, as both adolescent disorders predicted at age 21: anxiety disorder, multiple drug use, early school leaving, low school attainment, any cohabitation, pregnancy, and early child bearing.
A category-theoretic account of program modules
Authors: Moggi Eugenio
Published: March 2009

The type-theoretic explanation of modules proposed to date (for programming languages like ML) is unsatisfactory, because it does not capture that the evaluation of type-expressions is independent from the evaluation of program expressions. We propose a new explanation based on ‘programming languages as indexed categories’ and illustrate how ML can be extended to support higher order modules, by developing a category-theoretic semantics for a calculus of modules with dependent types. The paper also outlines a methodology, which may lead to a modular approach in the study of programming languages.
Equational axioms for regular sets
Authors: Bloom S. L. , Ésik Z.
Published: March 2009

We show that, aside from the semiring equations, three equations and two equation schemes characterize the semiring of regular sets with the Kleene star operation.
Some monoidal closed categories of stable domains and event structures
Authors: Zhang Guo-Qiang
Published: March 2009

This paper introduces the following new constructions on stable domains and event structures: the tensor product; the linear function space; and the exponential. These give rise to a monoidal closed category of dI-domains and to stable event structures, which can be used to interpret intuitionistic linear logic. Finally, the usefulness of the category of stable event structures for modeling concurrency and its relation to other models are discussed.
Program specification and data refinement in type theory
Authors: Luo Zhaohui
Published: March 2009

The study of type theory may offer a uniform language for modular programming, structured specification and logical reasoning. We develop an approach to program specification and data refinement in a type theory with a strong logical power and nice structural mechanisms to show that it provides an adequate formalism for modular development of programs and specifications. Specification of abstract data types is considered, and a notion of abstract implementation between specifications is defined in the type theory and studied as a basis for correct and modular development of programs by stepwise refinement. The higher-order structural mechanisms in the type theory provide useful and flexible tools (specification operations and parameterized specifications) for modular design and structured specification. Refinement maps (programs and design decisions) and proofs of implementation correctness can be developed by means of the existing proof development systems based on type theories.
Fully abstract translations between functional languages
Authors: Riecke Jon G.
Published: March 2009

We examine the problem of finding fully abstract translations between programming languages, i.e., translations that preserve code equivalence and nonequivalence. We present three examples of fully abstract translations: one from call-by-value to lazy PCF, one from call-by-name to call-by-value PCF, and one from lazy to call-by-value PCF. The translations yield lower bounds on decision procedures for proving equivalences of code. We define a notion of ‘functional translation’ that captures the essence of the proofs of full abstraction, and show that some languages cannot be translated into others.
The mix rule
Authors: Fleury Arnaud , Retoré Christian
Published: March 2009

We have found both a proofnet criterion and a sequent calculus for the multiplicative fragment with units ( ⊗1,℘,0, atoms), but without the ┴-boxes of Girard (1987), which differentiate between 1 and ┴. We have also proved that for any of our proofnets there is a corresponding sequential proof.
A categorical look at tree automata and context-free languages
Authors: Rosenthal Kimmo I.
Published: March 2009

In this article, we indicate how the category theoretical approach to tree automata, due to Betti and Kasangian, can be fruitfully combined with Walters’ categorical approach to context-free grammars to provide a simple way of establishing the well-known correspondence between context-free languages and the behaviors of non-deterministic tree automata. The connecting link between the two notions is provided by the theory of relational presheaves.
Primitive recursion, equality, and a universal set
Authors: Pfender M. , Kröplin M. , Pape D.
Published: March 2009

Within a categorical framework for primitive recursion, equality between p.r. maps is shown to be definable by suitable p.r. equality predicates. Equivalence is shown between a direct categorical formalization of classical p.r. functions and p.r. maps in the sense of Lawvere and Freyd. An extension of the theory is shown to admit a ‘universal set’ containing all objects of the extended theory of subobjects.
Simulating expansions without expansions
Authors: Cosmo Roberto Di , Kesner Delia
Published: March 2009

We add extensional equalities for the functional and product types to the typed λ-calculus with, in addition to products and terminal object, sums and bounded recursion (a version of recursion that does not allow recursive calls of infinite length). We provide a confluent and strongly normalizing (thus decidable) rewriting system for the calculus that stays confluent when allowing unbounded recursion. To do this, we turn the extensional equalities into expansion rules, and not into contractions as is done traditionally. We first prove the calculus to be weakly confluent, which is a more complex and interesting task than for the usual λ-calculus. Then we provide an effective mechanism to simulate expansions without expansion rules, so that the strong normalization of the calculus can be derived from that of the underlying, traditional, non-extensional system. These results give us the confluence of the full calculus, but we also show how to deduce confluence directly form our simulation technique without using the weak confluence property.
Dynamic labeled 2-structures
Authors: Ehrenfeucht A. , Rozenberg G.
Published: March 2009

The notion of adynamic labeled 2-structure(dℓ2s) is introduced and investigated. It generalizes the notion of a labeled 2-structure (ℓ2s) (Ehrenfeucht and Rozenberg 1990), by making it possible to change the (label) relationships between the nodes. This is achieved by storing in the nodes of a ℓ2s output and input functions that can change the outgoing and incoming labels, respectively. The notion of a clan, which is central in the theory of ℓ2s's is transferred to the framework of dℓ2s's, and the basic properties of clans of dℓ2s's are investigated.
Interaction Systems I: The theory of optimal reductions
Authors: Asperti Andrea , Laneve Cosimo
Published: March 2009

We introduce a new class of higher order rewriting systems, called Interaction Systems (IS's). IS's are derived from Lafont's (Intuitionistic) Interaction Nets (Lafont 1990) by dropping the linearity constraint. In particular, we borrow from Interaction Nets the syntactical bipartitions of operators into constructors and destructors and the principle of binary interaction. As a consequence, IS's are a subclass of Klop's Combinatory Reduction Systems (Klop 1980), where the Curry-Howard analogy still ‘makes sense’. Destructors and constructors, respectively, correspond to left and right logical introduction rules: interaction is cut and reduction is cut-elimination.

Interaction Systems have been primarily motivated by the necessity of extending the practice of optimal evaluators for λ-calculus (Lamping 1990; Gonthier et al. 1992a) to other computational constructs such as conditionals and recursion. In this paper we focus on the theoretical aspects of optimal reductions. In particular, we generalize the family relation in Lévy (1978; 1980), thus defining the amount of sharing an optimal evaluator is required to perform. We reinforce our notion of family by approaching it in two different ways (generalizing labelling and extraction in Levy (1980)) and proving their coincidence. The reader is referred to Asperti and Laneve (1993c) for the paradigmatic description of optimal evaluators of IS's.
Efficient recursive subtyping
Authors: Kozen Dexter , Palsberg Jens , Schwartzbach Michael I.
Published: March 2009

Subtyping in the presence of recursive types for the λ-calculus was studied by Amadio and Cardelli in 1991 (Amadio and Cardelli 1991). In that paper they showed that the problem of deciding whether one recursive type is a subtype of another is decidable in exponential time. In this paper we give an 0(n2) algorithm. Our algorithm is based on a simplification of the definition of the subtype relation, which allows us to reduce the problem to the emptiness problem for a certain finite automaton with quadratically many states.

It is known that equality of recursive types and the covariant Bohm order can be decided efficiently by means of finite automata, since they are just language equality and language inclusion, respectively. Our results extend the automata-theoretic approach to handle orderings based on contravariance.
Algebraic implementation of abstract data types: a survey of concepts and new compositionality results
Authors: Orejas Fernando , Navarro Marisa , Sánchez Ana
Published: March 2009

In this paper we try to shed some light on the similarities and differences in the different approaches denning the notions of implementation and implementation correctness. For obvious reasons, we do not discuss all existing approaches individually. Instead, a formal framework is introduced in order to discuss the most important ones. Additionally, we discuss some issues, which in our opinion are often misunderstood, concerning transitivity of implementation correctness and its role in the software development process. In particular, on the one hand, we show that for reasonable notions of implementation, it is almost impossible to prove transitivity of implementation correctness at the specification level. On the other hand, we show that this is not really important if the programming language satisfies the properties of horizontal and vertical composition.
Axiomatizing permutation equivalence
Authors: Laneve Cosimo , Montanari Ugo
Published: March 2009

We axiomatizepermutation equivalencein term rewriting systems and Klop’s orthogonal Combinatory Reduction Systems (Klop 1980). The axioms for the former are provided by the general approach proposed by Meseguer (Meseguer 1992). The latter need extra axioms modelling the interplay between reductions and the operation of substitution.

As a consequence of this work, the definition of permutation equivalence is rid of residual calculi, which are heavy in general.
Mirror, mirror in my hand: a duality between specifications and models of process behaviour
Authors: Fiadeiro J. L. , Costa J. F.
Published: March 2009

Since Pnueli’s seminal paper in 1977, Temporal Logic has been used as a formalism for specifying and verifying the correctness of reactive systems. In this paper, we show that, besides its expressive power, Temporal Logic enjoys a very strong structural property: it is categorical on processes. That is, we show how temporal specifications (as theories) can be embedded in categories of process behaviour, and out of this adjunction we build an institution that is categorical in the sense of Meseguer. This characterisation means that temporal logic is, in a sense, ‘sound and complete’ with respect to process specification and interconnection techniques.
Coherence of subsumption, minimum typing and type-checking in F ≤
Authors: Curien Pierre-Louis , Ghelli Giorgio
Published: March 2009

A subtyping relation ≤ between types is often accompanied by a typing rule, called subsumption: if a term a has type T and T≤U, then a has type U. In presence of subsumption, a well-typed term does not codify its proof of well typing. Since a semantic interpretation is most naturally defined by induction on the structure of typing proofs, a problem of coherence arises: different typing proofs of the same term must have related meanings. We propose a proof-theoretical, rewriting approach to this problem. We focus on F≤, a second-order lambda calculus with bounded quantification, which is rich enough to make the problem interesting. We define a normalizing rewriting system on proofs, which transforms different proofs of the same typing judgement into a unique normal proof, with the further property that all the normal proofs assigning different types to a given term in a given environment differ only by a final application of the subsumption rule. This rewriting system is not defined on the proofs themselves but on the terms of an auxiliary type system, in which the terms carry complete information about their typing proof. This technique gives us three different results:

— Any semantic interpretation is coherent if and only if our rewriting rules are satisfied as equations.

— We obtain a proof of the existence of a minimum type for each term in a given environment.

— From an analysis of the shape of normal form proofs, we obtain a deterministic typechecking algorithm, which is sound and complete by construction.
Sound and complete axiomatisations of call-by-value control operators
Authors: Hofmann Martin
Published: March 2009

We formulate a typed version of call-by-value λ-calculus containing variants of Felleisen's control operators A and C that provide explicit access to continuations and logically extend the propositions-as-types correspondence to classical propositional logic. We give an equational theory for this calculus, which is shown to be sound and complete with respect to a class of categorical models based on continuation-passing-style semantics.
Order-enrichment for categories of partial maps
Authors: Fiore Marcelo P.
Published: March 2009

Motivated by a desire to treat non-termination directly in the semantics of computation, the notion of approximation between programs is studied in the context of categories of partial maps. In particular, contextual approximation and specialisation are considered and shown to coincide. Moreover, after exhibiting the approximation between total maps as a primitive notion, from an arbitrary (or axiomatic) approximation order on total maps a computationally natural approximation order on partial maps is derived. The main technical contribution is a characterisation of when this approximation order between partial maps is domain-theoretic (in the sense that the category of partial mapsCpo-enriches) provided that the approximation order between total maps is also.
Temporal Structures
Authors: Casley Ross , Crew Roger F. , Meseguer José , Pratt Vaughan
Published: March 2009

We combine the principles of the Floyd-Warshall-Kleene algorithm, enriched categories, and Birkhoff arithmetic, to yield a useful class of algebras of transitive vertex-labeled spaces. The motivating application is a uniform theory of abstract or parametrized time in which to any given notion of time there corresponds an algebra of concurrent behaviors and their operations, always the same operations but interpreted automatically and appropriately for that notion of time. An interesting side application is a language for succinctly naming a wide range of datatypes.
Representing Control: a Study of the CPS Transformation
Authors: Danvy Oliver , Filinski Andrzex
Published: March 2009

This paper investigates the transformation of λν-terms into continuation-passing style (CPS). We show that by appropriate η-expansion of Fisher and Plotkin's two-pass equational specification of the CPS transform, we can obtain a static and context-free separation of the result terms into “essential” and “administrative” constructs. Interpreting the former as syntax builders and the latter as directly executable code, We obtain a simple and efficient one-pass transformation algorithm, easily extended to conditional expressions, recursive definitions, and similar constructs. This new transformation algorithm leads to a simpler proof of Plotkin's simulation and indifference results.

We go on to show how CPS-based control operators similar to, more general then, Scheme's call/cc can be naturally accommodated by the new transformation algorithm. To demonstrate the expressive power of these operators, we use them to present an equivalent but even more concise formulation of the efficient CPS transformation algorithm. Finally, we relate the fundamental ideas underlying this derivation to similar concepts from other work on program manipulation; we derive a one-pass CPS transformation of λn-terms; and we outline some promising areas for future research.