329 research outputs found
A Determinacy Testing Algorithm for Nondeterminate Flat Concurrent Logic Programming Languages
39 pagesThis paper describes an algorithm for the code generation of determinacy testing
for nondeterminate flat concurrent logic programming languages. Languages such
as Andorra and Pandora require that procedure invocations suspend if there is
more than one candidate clause potentially satisfying the goal. The algorithm
described has been developed specifically for a variant of flat Pandora based on
FGHC, although the concepts are general. We have extended Kliger and Shapiro's
decision-graph construction algorithm to compile "don't know" procedures which
must suspend for nondeterminate goal invocation. The determinacy test is compiled
into a decision graph quite different from those of committed-choice procedures, but
we argue that in most cases, the same low space complexity is retained
Examining the genetic and environmental associations between autistic social and communication deficits and psychopathic callous-unemotional traits
- BACKGROUND: Difficulties in appropriate social interaction are characteristic of both children with autism spectrum disorders and children with callous-unemotional traits (who are at risk of developing psychopathy). Extant experimental studies suggest that the nature of atypical social cognition that characterises these two profiles is not identical. However, 'empathizing' difficulties have been hypothesised for both groups, raising questions about the degree of aetiological separation between social impairments that characterize each disorder. This study explored the relative contribution of independent vs. shared aetiological influences to social and communication impairments associated with autistic traits and callous-unemotional traits, indexed by parent-report in a population-based cohort of twins.
- METHODS: Participants were over 5,000 twin pairs from a UK cohort (the Twins Early Development Study; TEDS), assessed for callous-unemotional traits at 7 years and autistic social and communication impairments at 8 years. Multivariate model-fitting was used to explore the relative contribution of independent vs. overlapping genetic/environmental influences on these traits.
- RESULTS: Both social and communication impairments and callous-unemotional traits were highly heritable, although the genetic and environmental influences accounting for individual differences on each domain were predominantly independent.
- CONCLUSIONS: Extant evidence from experimental and neuro-imaging studies has suggested that, despite some superficially overlapping behaviours, the social difficulties seen in children with autism spectrum disorders and callous-unemotional traits are largely distinct. The current study is the first to demonstrate considerable aetiological independence of the social interaction difficulties seen in children with autism spectrum disorders and those with callous-unemotional traits
Black Mesoporous Silicon as a Contrast Agent for LED-Based 3D Photoacoustic Tomography
Mesoporous silicon (PSi) nanoparticles have been widely studied in different biomedical imaging modalities due to their several beneficial material properties. However, they have not been found to be suitable for photoacoustic imaging due to their poor photothermal conversion performance. In the present study, biodegradable black mesoporous silicon (BPSi) nanoparticles with strong light absorbance were developed as superior image contrast agents for photoacoustic tomography (PAT), which was realized with a light-emitting diode (LED) instead of the commonly used laser. LED-based PAT offers the advantages of low cost, compactness, good mobility, and easy operation as compared to the traditional laser-based PAT modality. Nevertheless, the poor imaging sensitivity of the LED-PAT systems has been the main barrier to prevent their wide biomedical application because the LED light has low optical energy. The present study demonstrated that the imaging sensitivity of the LED-PAT system was significantly enhanced with the PEGylated BPSi (PEGâBPSi) nanoparticles. The PEGâBPSi nanoparticles were clearly detectable with a low concentration of 0.05 mg/mL in vitro and with an LED radiation energy of 5.2 ÎŒJ. The required concentration of the PEGâBPSi nanoparticles was 10 times lesser than that of the reference gold nanoparticles to reach the corresponding level of the imaging contrast. The ex vivo studies demonstrated that the submillimeter BPSi nanoparticle-based absorbers were distinguishable in chicken breast tissues. The strong contrast provided by the BPSi particles indicated that these particles can be utilized as novel contrast agents in PAT, especially in LED-based systems with low light intensity
The &-prolog system: Exploiting independent and-parallelism
The &-Prolog system, a practical implementation of a parallel execution niodel for Prolog exploiting strict and non-strict independent and-parallelism, is described. Both automatic and manual parallelization of programs is supported. This description includes a summary of the system's language and architecture, some details of its execution model (based on the RAP-WAM model), and data on its performance on sequential workstations and shared memory multiprocessors, which is compared to that of current Prolog systems. The results to date show significant speed advantages over state-of-the-art sequential systems
Effects of Key2Teach on students' externalising and social-emotional problem behaviours, mediated by the teacher-student relationship
Teaching students with externalising problem behaviours is difficult for teachers, as it challenges the relationship that teachers engage in with their students. In this study, effects of Key2Teach on externalising and social-emotional problem behaviours and the mediating role of conflict in the teacher-student relationship were studied using a randomised controlled trial (RCT)-design. In two cohorts, 103 teacher-student dyads and peer-students (n = 1643) were assessed two times during a school year. Fifty-three dyads received the intervention (experimental group), whereas 50 dyads received no intervention (control group). Data were collected on teacher-reported externalising and social-emotional problem behaviours in students, and on teacher-student conflict. For dyad-students, results showed a direct effect of Key2Teach on conduct problems and an indirect effect, via teacher-student conflict, for hyperactivity problems. No effects on social-emotional problems were established. For peer-students, results showed indirect effects on externalising problems and direct effects on social-emotional problems. Implications for practice and future research are discussed
The impact of teacher's self-efficacy and classroom externalising problem behaviors on emotional exhaustion:Between- and within-person associations
Teaching can be a challenging profession, which puts teachers at high risk for developing burnout symptoms, such as emotional exhaustion. In this study we aim to investigate the interplay between classroom externalising problem behaviours (as a job demand), teachersâ self-efficacy (as a job resource) and emotional exhaustion over a school year. Conducting three measurements during a school year among 103 Dutch primary education teachers, we examine the sensitivity for, and the individual development of, emotional exhaustion. Findings show that emotional exhaustion, classroom externalising problem behaviours, and teachersâ self-efficacy are stable constructs in teachers. Traditional (between-person) cross-lagged panel models indicate that teachers with low levels of self-efficacy are more likely to develop emotional exhaustion during the school year, compared to their colleagues. We found no evidence that teachers confronted with classroom externalising problem behaviours were more likely to develop emotional exhaustion. Random intercept (within-person) cross-lagged panel models indicate that teachers with high levels of classroom externalising problem behaviours do not show increased emotional exhaustion at a later time point. For self-efficacy and emotional exhaustion, we could not estimate the within-person model due to limited variance in the variables. Implications of these findings and suggestions for further research were discussed
Assessing Inclusion Behaviors and Impact of Inclusion within the Fleet
NPS NRP Executive SummaryThis project supports the Navyâs efforts to promote diversity and inclusion (D&I), which are recognized as strategic imperatives that give the Navy a warfighting advantage against our adversaries. The study utilizes both quantitative and qualitative approaches to understand the major contributing factors to an inclusive and diverse command, accomplishing four research objectives: (1) developing metrics to assess behaviors of inclusion within the fleet; (2) assessing inclusion behaviors within the fleet using the developed metrics; (3) determining the most impactful D&I competencies for building inclusion; and (4) identifying command practices that contribute to greater acceptance of diversity. We develop and introduce a survey instrument to assess Personal Inclusion Factors (individualsâ feelings of being personally included within their command) and Command Core Inclusion Competencies (individualsâ beliefs about how their commands demonstrate practices that promote diversity and inclusion) suitable for a Navy context. The instrument captures best practices and validated metrics for promoting and assessing D&I in organizations and tailors them to the Navy and Sailorsâ work. We fielded this survey to 489 active-duty Navy personnel (enlisted and officers) asking them to report on both their current and past commands. We find that females across all race/ethnicities on average report lower feelings of inclusion and rate commands lower on Core Command Inclusion Competencies than their male counterparts. This gender difference is stronger for sea versus shore commands. Participants also answered open-ended questions about the competencies that they believed were most important for promoting D&I in the fleet. "Inclusive leadership" emerged as a dominant theme; in particular, participants felt most included in commands where leadership valued their perspectives and ideas and where Sailors felt heard on a day-in, day-out basis.N1 - Manpower, Personnel, Training & EducationThis research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.
Assessing Inclusion Behaviors and Impact of Inclusion within the Fleet
NPS NRP Project PosterThis project supports the Navyâs efforts to promote diversity and inclusion (D&I), which are recognized as strategic imperatives that give the Navy a warfighting advantage against our adversaries. The study utilizes both quantitative and qualitative approaches to understand the major contributing factors to an inclusive and diverse command, accomplishing four research objectives: (1) developing metrics to assess behaviors of inclusion within the fleet; (2) assessing inclusion behaviors within the fleet using the developed metrics; (3) determining the most impactful D&I competencies for building inclusion; and (4) identifying command practices that contribute to greater acceptance of diversity. We develop and introduce a survey instrument to assess Personal Inclusion Factors (individualsâ feelings of being personally included within their command) and Command Core Inclusion Competencies (individualsâ beliefs about how their commands demonstrate practices that promote diversity and inclusion) suitable for a Navy context. The instrument captures best practices and validated metrics for promoting and assessing D&I in organizations and tailors them to the Navy and Sailorsâ work. We fielded this survey to 489 active-duty Navy personnel (enlisted and officers) asking them to report on both their current and past commands. We find that females across all race/ethnicities on average report lower feelings of inclusion and rate commands lower on Core Command Inclusion Competencies than their male counterparts. This gender difference is stronger for sea versus shore commands. Participants also answered open-ended questions about the competencies that they believed were most important for promoting D&I in the fleet. "Inclusive leadership" emerged as a dominant theme; in particular, participants felt most included in commands where leadership valued their perspectives and ideas and where Sailors felt heard on a day-in, day-out basis.N1 - Manpower, Personnel, Training & EducationThis research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE 0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)Approved for public release. Distribution is unlimited.
Effect of Key2Teach on Dutch teachers' relationships with students with externalizing problem behavior:A randomized controlled trial
The teacher-student relationship plays an important role in the academic and behavioral development of primary school children with externalizing problem behavior. However, such problem behavior often threatens the quality of the teacher-student relationship. Teacher-focused coaching intervention Key2Teach aims to improve elements of the relationship between teachers and students with externalizing problem behavior and consists of two phases and four building blocks. This intervention provides primary school teachers with insight into their mental representation of the relationship and opportunities to practice functional interaction skills. In a randomized controlled trial (RCT), effects of Key2Teach on different aspects of the relationship between teachers and students with externalizing problem behavior were examined. In two cohorts, 103 dyads consisting of a teacher and a student with externalizing problem behavior in grades 3-6 were assessed three times during a school year. Fifty-three dyads received the intervention (intervention group), whereas 50 dyads received no intervention (control group). Data were collected on teacher-reported teacher-student closeness and conflict, and on teacher interaction skills in various domains. Results show a significant increase in closeness and a decrease in conflict as a result of Key2Teach, with substantial effect sizes. No effects on teacher interaction skills were found. This study indicates that Key2Teach may help teachers to improve elements of the relationship they have with students with externalizing problem behavior. Implications for practice and future research are discussed
GHQ increases among Scottish 15 year olds 1987â2006
BACKGROUND:
Increases in a number of psychosocial disorders have been identified among Western youth in the second half of the Twentieth century. However findings are not consistent, trends are complex, and comparisons over time are hampered by methodological problems.
METHODS:
Data were drawn from three samples identical in respect of age (15 years), school year (final year of statutory schooling) and geographical location (the West of Scotland). Each sample was administered the 12-item General Health Questionnaire, a measure of self-report psychological distress, in 1987 (N = 505), 1999 (N = 2,196) and 2006 (N = 3,194). Analyses were conducted to examine changes in: GHQ 'caseness'; individual items; and factors, derived via confirmatory factor analysis representing (a) 'negative' and 'positive' items, and (b) 'anxiety and depression', 'loss of confidence or self-esteem' and 'anhedonia and social dysfunction'.
RESULTS:
Based on the standard (2/3) cut-off, 'caseness' rates in 1987, 1999 and 2006 were 12.7, 15.1 and 21.5% (males) and 18.8, 32.5 and 44.1% (females). Similar increases were observed with more stringent 'caseness' cut-offs. Examination of individual items showed some to have increased much more markedly over time than others. There were larger increases among females for all except two items and some evidence, among both genders, of steeper increases among 'negative' items compared with 'positive' ones. However, the differences in slope were very small compared with the overall increases in both types.
CONCLUSIONS:
Data from three samples identical in respect of age, school year and geographical location, show marked increases in GHQ-12 'caseness' among females between 1987 and 1999 and among both males and females between 1999 and 2006. Although slightly steeper increases in 'negative' items raise the possibility that endorsing such symptoms may have become more acceptable, these were small in comparison with increases in all dimensions of psychological distress. The next step is to identify causal explanations for the increases reported here
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