Do children use different forms of verbal rehearsal in serial picture recall tasks? A multi-method study

Use of verbal rehearsal is a key issue in memory development. However, we still lack detailed and triangulated information about the early development and the circumstances in which different forms of rehearsal are used. To further understand significant factors that affect children’s use of various forms of rehearsal, the present study involving 108 primary school children adopted a multi-method approach. It combined a carefully chosen word length effect method with a self-paced presentation time method to obtain behavioural indicators of verbal rehearsal. In addition, subsequent trial-by-trial self-reports were gathered. Word length effects in recall suggested that phonological recoding (converting images to names - a necessary precursor for rehearsal) took place, with evidence of more rehearsal among children with higher performance levels. According to self-paced presentation times, cumulative rehearsal was the dominant form of rehearsal only for children with higher spans on difficult trials. The combined results of self-paced times and word length effects in recall suggest that ‘naming’ as simple form of rehearsal was dominant for most children. Self-reports were in line with these conclusions. Additionally, children used a mixture of strategies with considerable intra-individual variability, yet strategy use was nevertheless linked to age as well as performance levels

Creating topological interfaces and detecting chiral edge modes in a 2D optical lattice

We propose and analyze a general scheme to create chiral topological edge modes within the bulk of two-dimensional engineered quantum systems. Our method is based on the implementation of topological interfaces, designed within the bulk of the system, where topologically-protected edge modes localize and freely propagate in a unidirectional manner. This scheme is illustrated through an optical-lattice realization of the Haldane model for cold atoms, where an additional spatially-varying lattice potential induces distinct topological phases in separated regions of space. We present two realistic experimental configurations, which lead to linear and radial-symmetric topological interfaces, which both allows one to significantly reduce the effects of external confinement on topological edge properties. Furthermore, the versatility of our method opens the possibility of tuning the position, the localization length and the chirality of the edge modes, through simple adjustments of the lattice potentials. In order to demonstrate the unique detectability offered by engineered interfaces, we numerically investigate the time-evolution of wave packets, indicating how topological transport unambiguously manifests itself within the lattice. Finally, we analyze the effects of disorder on the dynamics of chiral and non-chiral states present in the system. Interestingly, engineered disorder is shown to provide a powerful tool for the detection of topological edge modes in cold-atom setups.Comment: 18 pages, 21 figure

Executive functioning and verbal fluency in children with language difficulties

This study provided a detailed analysis of verbal fluency in children with language difficulties, and examined the relative contributions of executive functioning (executive-loaded working memory, switching, inhibition) and language ability to verbal fluency performance. Semantic and phonemic fluency, language, and executive functioning tasks were completed by 41 children with specific language impairment (SLI) and 88 children with typical development. Children with SLI showed difficulties with most aspects of verbal fluency (rates of output, errors, switching) relative to typical children. Language ability predicted nearly every aspect of phonemic fluency performance and some aspects of semantic fluency performance. The relationships between verbal fluency and executive functioning were modest: inhibition was related to error scores on the phonemic fluency task, but relationships with executive-loaded working memory and switching were absent. Educationally, these results emphasise the underlying importance of language abilities in generation tasks like verbal fluency, but point to the importance of inhibition skills for error monitoring. Interventions to improve search and generation abilities have the potential to offer broader benefits in the classroom for children with language difficulties

A novel approach to track finding in a drift tube chamber

A novel track finding approach for drift tube detectors

An adjudicated hermeneutic single-case efficacy design study of experiential therapy for panic/phobia

This paper illustrates the application of an adjudicated form of Hermeneutic Single Case Efficacy Design (HSCED), a critical-reflective method for inferring change and therapeutic influence in single therapy cases. The client was a 61 year-old European-American male diagnosed with panic and bridge phobia. He was seen for 23 sessions of individual Process-Experiential/Emotion-Focused Therapy. In this study, affirmative and skeptic teams of researchers developed opposing arguments regarding whether the client changed over therapy and whether therapy was responsible for these changes. Three judges representing different theoretical orientations then assessed data and arguments, rendering judgments in favor of the affirmative side. We discuss clinical implications and recommendations for the future interpretive case study research

Crossovers from parity conserving to directed percolation universality

The crossover behavior of various models exhibiting phase transition to absorbing phase with parity conserving class has been investigated by numerical simulations and cluster mean-field method. In case of models exhibiting Z_2 symmetric absorbing phases (the NEKIMCA and Grassberger's A stochastic cellular automaton) the introduction of an external symmetry breaking field causes a crossover to kink parity conserving models characterized by dynamical scaling of the directed percolation (DP) and the crossover exponent: 1/\phi ~ 0.53(2). In case an even offspringed branching and annihilating random walk model (dual to NEKIMCA) the introduction of spontaneous particle decay destroys the parity conservation and results in a crossover to the DP class characterized by the crossover exponent: 1/\phi\simeq 0.205(5). The two different kinds of crossover operators can't be mapped onto each other and the resulting models show a diversity within the DP universality class in one dimension. These 'sub-classes' differ in cluster scaling exponents.Comment: 6 pages, 6 figures, accepted version in PR

The dental service and dental health of Northern Newfoundland and Labrador: a twenty year study

Dental Health Care has been provided by the Grenfell Association for the people of Northern Newfoundland and Labrador since the late 1800’s. The capability to provide dental care has been influenced by many factors including a small population living in isolated communities over an enormous geographical area with adverse climatic conditions and long lines of communication. Transportation alone presented a formidable challenge. Based on his early experience with the Association between 1964-69, the author realised, on his return to Canada in 1976 that there was need to identify major problems, adapt existing facilities and change established philosophies, as well as to introduce new systems and methods to improve dental health-care delivery. The main areas of concern were the high prevalence of dental disease, the lack of adequate manpower, appalling working conditions and lack of overall policies. Initially, one of the major tasks was to establish basic equipment at each clinic. Small portable light-weight dental units were designed and constructed by the author, for each dentist with a travelling commitment, these units being readily connected to on-site compressors. Thereafter, a longterm policy of equipment upgrading and replacement was pursued to enable dental staff to undertake a complete range of clinical duties. Later, when new Health Centres and Nursing Stations were established, the author had the opportunity to become involved in their design and layout. The method of dental service financing also contributed to many of the problems. Thus the existing monetary arrangements had to be studied which, in turn, required an understanding of the sources of funding. Hence, following analysis of financial data collected after only the first few months of 1976, it became clear that several issues required urgent action and, as monetary considerations appeared to be the crux or the problem, the author decided to introduce a standard billing system which was applied throughout the region. This was primarily operated by dental assistants to provide continuity between dental staff changes. To reduce financial hardship, fee increases to conform with general dental fees charged elsewhere in Newfoundland were introduced gradually over a five year period. When sufficient data on the work being undertaken via the Provincial Dental Programme became available, Department of Health funding was evaluated. This led to a report and submission to the Department of Health in 1977, which was intended to exert pressure for fairer remuneration of the Grenfell Dental Service. The effect of the measures taken by the author to increase manpower, improve facilities, reduce caries prevalence, introduce preventive measures and modify unfavourable treatment patterns has been evaluated continuously throughout his tenure as Co-ordinator and subsequently as Chief of Dental Services. The establishment of administrative pathways and centralised procedures has also provided evidence of change. In addition, further recommendations regarding future priorities have been formulated to ensure continuous staff recruitment and supporting facilities required to achieve the W.H.O. dental goals set for the year 2000. Happily, with 10 years of the Century remaining, a further mean DMFT reduction of only 0.82 per child is now required to meet the target of 3.0 for 12-yr-olds