Transport properties of heterogeneous materials derived from Gaussian random fields: Bounds and Simulation

We investigate the effective conductivity ($\sigma_e$) of a class of amorphous media defined by the level-cut of a Gaussian random field. The three point solid-solid correlation function is derived and utilised in the evaluation of the Beran-Milton bounds. Simulations are used to calculate $\sigma_e$ for a variety of fields and volume fractions at several different conductivity contrasts. Relatively large differences in $\sigma_e$ are observed between the Gaussian media and the identical overlapping sphere model used previously as a `model' amorphous medium. In contrast $\sigma_e$ shows little variability between different Gaussian media.Comment: 15 pages, 14 figure

Academic language socialisation in high school writing conferences

This study examines multilingual high school writers’ individual talk with their teachers in two advanced English language development classes to observe how such talk shapes linguistically diverse adolescents’ writing. Addressing adolescent writers’ language socialization through microethnographic discourse analysis, the author argues that teachers’ oral responses during writing conferences can either scaffold or deter students’ socialization into valued ways of using academic language for school writing. She suggests what forms of oral response provide scaffolding and what forms might limit multilingual adolescent learners’ academic literacy. Constructive interactions engaged students in dialogue about their writing, and students included content or phrasing from the interaction in their texts. Unhelpful interactions failed to foster students’ language development in observable ways. Although teachers attempted to scaffold ideas and language, they often did not guide students’ discovery of appropriate forms or points. These interactions represent restrictive academic language socialization: while some students did create academic texts, they learned little about academic language use

Positive youth development in swimming: clarification and consensus of key psychosocial assets

The purpose of this study was to gain a more cohesive understanding of the assets considered necessary to develop in young swimmers to ensure both individual and sport specific development. This two stage study involved (a) a content analysis of key papers to develop a list of both psychosocial skills for performance enhancement and assets associated with positive youth development, and (b) in-depth interviews involving ten expert swim coaches, practitioners and youth sport scholars. Five higher order categories containing seventeen individual assets emerged. These results are discussed in relation to both existing models of positive youth development and implications for coaches, practitioners and parents when considering the psychosocial development of young British swimmers

Lessons learned from COVID-19 Lockdown: An ASPED/MENA Study on Lifestyle Changes and Quality of Life during Ramadan Fasting in Children and Adolescents living with Type 1 Diabetes

Background: Lockdown was a unique experience that affected many aspects of life, particularly during the challenge of Ramadan fasting (RF). Studying this can increase understanding of the effects of lifestyle changes on quality of life (QoL) for children with type 1 diabetes (T1D) during RF. Methods: A cross-sectional study that assessed the effect of lockdown on lifestyle and QoL on fasting children living with T1D during Ramadan in the Middle East and North Africa region (2020-2021). We compared the child (self) and parent (proxy) reports using PEDQoL v3.0 disease specific questionnaire during lockdown and non-lockdown periods, and assessed correlations with lifestyle changes using regression and gap analyses. Results: A total of 998 reports from 499 children with T1D aged 8-18 years (study=276, control=223), and their parents during RF in lockdown and non-lockdown periods. Fathers were more involved in their children’s care during lockdown (p=0.019). Patients had better compliance with treatment (p= 0.002), a reversed sleep pattern (p= 0.033), increased food intake (p=<0.001) and less exercise (p<0.001). Children and parents perceived better QoL during lockdown (p=<0.001) with no differences between their reports in “Diabetes Symptoms”, “Treatment Adherence” and “Communication” domains. Self and proxy reports were different in all domains during non-lockdown (p-values <0.001- 0.009). In gap analysis, although not statistically significant, the gap was approximated between children’s and parents’ perceptions in all domains during lockdown. Conclusion: COVID-19 lockdown had a positive impact on QoL of children living with T1D during RF, possibly due to lifestyle changes and superior psychosocial family dynamics

A study of empyema thoracis and role of intrapleural streptokinase in its management

BACKGROUND: Clinical spectrum, microbiology and outcome of empyema thoracis are changing. Intrapleural instillation of fibrinolytic agents is being increasingly used for management of empyema thoracis. The present study was carried out to describe the clinical profile and outcome of patients with empyema thoracis including those with chronic empyema and to study the efficacy and safety of intrapleural streptokinase in its management. METHODS: Clinical profile, etiological agents, hospital course and outcome of 31 patients (mean age 40 ± 16 years, M: F 25: 6) with empyema thoracis treated from 1998 to 2003 was analyzed. All patients were diagnosed on the basis of aspiration of frank pus from pleural cavity. Clinical profile, response to therapy and outcome were compared between the patients who received intrapleural streptokinase (n = 12) and those who did not (n = 19). RESULTS: Etiology was tubercular in 42% of the patients (n = 13) whereas the rest were bacterial. Amongst the patients in which organisms could be isolated (n = 13, 42%) Staphylococcus aureus was the commonest (n = 5). Intrapleural streptokinase was instilled in 12 patients. This procedure resulted in increase of drainage of pleural fluid in all patients. Mean daily pleural fluid drainage after streptokinase instillation was significantly higher for patients who received intrapleural streptokinase than those who did not (213 ml vs 57 ml, p = 0.006). Only one patient who was instilled streptokinase eventually required decortication, which had to be done in five patients (16.1%). Mean hospital stay was 30.2 ± 17.6 days whereas two patients died. CONCLUSIONS: Tubercular empyema is common in Indian patients. Intrapleural streptokinase appears to be a useful strategy to preserve lung function and reduce need for surgery in patients with late stage of empyema thoracis

Structure-property correlations in model composite materials

We investigate the effective properties (conductivity, diffusivity and elastic moduli) of model random composite media derived from Gaussian random fields and overlapping hollow spheres. The morphologies generated in the models exhibit low percolation thresholds and give a realistic representation of the complex microstructure observed in many classes of composites. The statistical correlation functions of the models are derived and used to evaluate rigorous bounds on each property. Simulation of the effective conductivity is used to demonstrate the applicability of the bounds. The key morphological features which effect composite properties are discussed

Individual, family and offence characteristics of high risk childhood offenders: comparing non-offending, one-time offending and re-offending Dutch-Moroccan migrant children in the Netherlands

<p>Abstract</p> <p>Background</p> <p>Childhood offenders are at an increased risk for developing mental health, social and educational problems later in life. An early onset of offending is a strong predictor for future persistent offending. Childhood offenders from ethnic minority groups are a vulnerable at-risk group. However, up until now, no studies have focused on them.</p> <p>Aims</p> <p>To investigate which risk factors are associated with (re-)offending of childhood offenders from an ethnic minority.</p> <p>Method</p> <p>Dutch-Moroccan boys, who were registered by the police in the year 2006-2007, and their parents as well as a control group (n = 40) were interviewed regarding their individual and family characteristics. Two years later a follow-up analysis of police data was conducted to identify one-time offenders (n = 65) and re-offenders (n = 35).</p> <p>Results</p> <p>All groups, including the controls, showed substantial problems. Single parenthood (OR 6.0) and financial problems (OR 3.9) distinguished one-time offenders from controls. Reading problems (OR 3.8), having an older brother (OR 5.5) and a parent having Dutch friends (OR 4.3) distinguished re-offenders from one-time offenders. First offence characteristics were not predictive for re-offending. The control group reported high levels of emotional problems (33.3%). Parents reported not needing help for their children but half of the re-offender's families were known to the Child Welfare Agency, mostly in a juridical framework.</p> <p>Conclusion</p> <p>The Moroccan subgroup of childhood offenders has substantial problems that might hamper healthy development. Interventions should focus on reaching these families tailored to their needs and expectations using a multi-system approach.</p