Percolation in Carbon Nanotube Networks

Carbon nanotubes (CNTs) have become increasingly useful in different applications since they were discovered in 1991 by Sumio Iijima [1]. One of their many useful qualities is their electronic properties [2]. These CNTs, when formed into a network, can be used as transistors [3] or biosensors [4]. Transistors are devices that regulate either current flow or voltage and act as a switch; they are a crucial component of computers. Biosensors detect the presence of biomolecules. Efficient transistors and biosensors already exist; however, they are expensive to manufacture compared to these CNT networks. The ability of the CNT networks to be transistors or biosensors relies on the percolation properties of the networks. As long as these networks percolate, current can pass through the network from a source electrode to a drain electrode, which can then be modulated by an electrical or biological signal to make devices such as transistors useful

Poetry With People With Dementia: An Evaluation of a Two Year Project Engaging in Poetry Activities With Older People in Residential and Nursing Homes.

This paper is a summary of an evaluation of the first two years of a three year poetry project for older people with dementia. The project was set up with a poet in residence who mentored six poets to deliver poetry activities to older people and those with dementia in residential and care homes in Herefordshire. The project was developed and run by the Courtyards Hereford. The evaluation was undertake through the use of questionnaires that were given to staff and carers undertaking training workshops and the poets, staff and carers in the homes who facilitated the activities and finally by the residents who took part in the project. The main findings were that participants that responded to the questionnaire for staff and carers it had increased confidence and assisted them in gaining more knowledge about the residents, whilst for residents it had a number of positive effects including enhanced communication, increased self-esteem and enhanced self-worth whilst making them feel less isolated

Comparisons Between Rail-Trail Users and Nonusers and Men and Women\u27s Patterns of Use in a Suburban Community

Background: Physical activity research on trails is limited. We compared rail-trail users and nonusers on demographics, physical activity, and barriers/concerns about trail use; and described use among men and women. Methods: Four hundred thirteen adults completed a physical activity survey during fall 1998. Chi-square statistics and t-tests were used to compare trail users to nonusers, and men and women on trail use. Results: More trail users (79%) performed recreational physical activity ≥ 3 d/wk, compared to nonusers (47%). Walking was the most common activity for trail users and nonusers. Both groups shared concerns about safe access to the trail and certain trail conditions. A higher percentage of female versus male users traveled to the trail by walking, walked on the trail, used the trail with a friend, and perceived that if the trail were not available their activity would decrease. Conclusions: Trail users perform more recreational physical activity than nonusers. Gender differences in trail use patterns should be considered in the design and promotion of trails

Naturally-Occurring Changes in Social-Cognitive Factors Modify Change in Physical Activity During Early Adolescence

Purpose To determine whether naturally-occurring changes in children’s motives and beliefs are associated with the steep decline in physical activity observed from childhood to early adolescence. Methods Latent growth modeling was applied in longitudinal tests of social-cognitive influences, and their interactions, on physical activity in a large cohort of boys and girls evaluated annually between 5th and 7th grades. Results Measurement equivalence of motives and beliefs was confirmed between boys and girls. After adjustment for gender and maturity differences, physical activity declined less in children who reported the least decreases in self-efficacy for overcoming barriers to activity and perceived parental support. Physical activity also declined less in students who persistently felt they had more parental and friend support for activity compared to those who reported the largest decrease in support from friends. After further adjustment for race, the decline in physical activity was less in those who had the largest decrease in perceived barriers and maintained a favorable perception of their neighborhood environment. Changes in enjoyment and social motives were unrelated to change in physical activity. Conclusion Using an objective measure of physical activity, we confirm that naturally-occurring changes in children’s beliefs about barriers to physical activity and their ability to overcome them, as well as perceptions of their neighborhood environment and social support, are concurrent with age-related declines in children’s physical activity. The longitudinal findings confirm these putative social-cognitive mediators as plausible, interacting targets of interventions designed to mitigate the marked decline in physical activity that occurs during the transition between elementary and middle schools

Using process evaluation for program improvement in dose, fidelity and reach: the ACT trial experience

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to demonstrate how formative program process evaluation was used to improve dose and fidelity of implementation, as well as reach of the intervention into the target population, in the "Active by Choice Today" (ACT) randomized school-based trial from years 1 to 3 of implementation.</p> <p>Methods</p> <p>The intervention integrated constructs from Self-Determination Theory and Social Cognitive Theory to enhance intrinsic motivation and behavioral skills for increasing long-term physical activity (PA) behavior in underserved adolescents (low income, minorities). ACT formative process data were examined at the end of each year to provide timely, corrective feedback to keep the intervention "on track".</p> <p>Results</p> <p>Between years 1 and 2 and years 2 and 3, three significant changes were made to attempt to increase dose and fidelity rates in the program delivery and participant attendance (reach). These changes included expanding the staff training, reformatting the intervention manual, and developing a tracking system for contacting parents of students who were not attending the after-school programs regularly. Process outcomes suggest that these efforts resulted in notable improvements in attendance, dose, and fidelity of intervention implementation from years 1 to 2 and 2 to 3 of the ACT trial.</p> <p>Conclusion</p> <p>Process evaluation methods, particularly implementation monitoring, are useful tools to ensure fidelity in intervention trials and for identifying key best practices for intervention delivery.</p

Children\u27s Understanding of the Concept of Physical Activity

This study evaluated 4th-grade students\u27 understanding of the concept of physical activity and assessed the effects of two interventions to enhance the students\u27 understanding of this concept. Students were randomly assigned to 1 of 3 conditions: the video group (n=40) watched a 5-min video describing physical activity; the verbal group (n=42) listened to a generic description of physical activity; the control group received no instruction (n=45). Students completed a 17-item checklist testing their understanding of the concept of physical activity. Compared to controls, students in the verbal and video group demonstrated significantly higher checklist scores, with the video group scoring significantly higher than the verbal group. Only 35.6% of the controls compared to 52.4% and 70.0% of the verbal and video group respectively, could classify \u3e 15 of the checklist items correctly. The results indicate that, without intervention, children have a limited understanding of the concept of physical activity

Tracking of Physical Activity, Physical Inactivity, and Health-Related Physical Fitness in Rural Youth

This study examined the tracking of selected measures of physical activity, inactivity, and fitness in a cohort of rural youth. Students (N=181, 54.7% female, 63.5% African American) completed test batteries during their fifth- (age=10.7±0.7 years), sixth-, and seventh-grade years. The Previous Day Physical Activity Recall (PDPAR) was used to assess 30-min blocks of vigorous physical activity (VPA), moderate-to-vigorous physical activity (MVPA), TV watching and other sedentary activities, and estimated energy expenditure (EE). Fitness measures included the PWC 170 cycle ergometer test, strength tests, triceps skinfold thickness, and BMI. Intraclass correlation coefficients (ICCs) for VPA, MVPA, and after-school EE ranged from 0.63 to 0.78. ICCs ranged from 0.49 to 0.71 for measures of inactivity and from 0.78 to 0.82 for the fitness measures. These results indicate that measures of physical activity, inactivity, and physical fitness tend to track during the transition from elementary to middle school

Statewide Dissemination and Implementation of Physical Activity Standards in Afterschool Programs: Two-Year Results

Background: In 2015, YMCA afterschool programs (ASPs) across South Carolina, USA pledged to achieve the YMCA physical activity standard calling for all children to accumulate 30 min of moderate-to-vigorous physical activity (MVPA) while attending their ASPs. This study presents the final two-year outcomes from the dissemination and implementation efforts associated with achieving this MVPA standard. Methods: Twenty ASPs were sampled from all South Carolina YMCA-operated ASPs (N = 97) and visited at baseline (2015) and first (2016) and second year (2017) follow-up. All ASPs were provided training to increase MVPA during the program by extending the scheduled time for activity opportunities and modifying commonly played games to increase MVPA. The RE-AIM framework was used to evaluate the statewide intervention. Accelerometer-derived MVPA was the primary outcome. Intent-to-treat (ITT) models were conducted summer 2017. Programs were also classified, based on changes in MVPA from 2015 to 2016 and 2016–2017, into one of three categories: gain, maintain, or lost. Implementation, within the three groups, was evaluated via direct observation and document review. Results: Adoption during the first year was 45% of staff attending training, with this increasing to 67% of staff during the second year. ITT models indicated no increase in the odds of accumulating 30 min of MVPA after the first year for either boys (odds ratio [OR] 1.06, 95CI 0.86–1.31) or girls (OR 1.14, 95CI 0.87–1.50), whereas an increase in the odds was observed during the second year for boys (OR 1.31, 95CI 1.04–1.64) and girls (OR 1.50 95CI 1.01–1.80). Programs that lost MVPA (avg. − 5 to − 7.5 min/d MVPA) elected to modify their program in a greater number of non-supportive ways (e.g., reduce time for activity opportunities, less time spent outdoors), whereas ASPs that gained MVPA (avg. + 5.5 to + 10.1 min MVPA) elected to modify their program in more supportive ways. Conclusions: The statewide study demonstrated minimal improvements in overall MVPA. However, child MVPA was dramatically influenced by ASPs who elected to modify their daily program in more supportive than non-supportive ways, with no one program modifying their program consistently across the multi-year initiative. These findings have important implications for organizations seeking to achieve the MVPA standard

Interventions with potential to reduce sedentary time in adults:Systematic review and meta-analysis

Context: Time spent in sedentary behaviours (SB) is associated with poor health, irrespective of the level of physical activity. The aim of this study was to evaluate the effect of interventions which included SB as an outcome measure in adults. Methods: Thirteen databases, including The Cochrane Library, MEDLINE and SPORTDiscus, trial registers and reference lists, were searched for randomised controlled trials until January 2014. Study selection, data extraction and quality assessment were performed independently. Primary outcomes included SB, proxy measures of SB and patterns of accumulation of SB. Secondary outcomes were cardiometabolic health, mental health and body composition. Intervention types were categorised as SB only, physical activity (PA) only, PA and SB or lifestyle interventions (PA/SB and diet). Results: Of 8087 records, 51 studies met the inclusion criteria. Meta-analysis of 34/51 studies showed a reduction of 22 min/day in sedentary time in favour of the intervention group (95% CI −35 to −9 min/day, n=5868). Lifestyle interventions reduced SB by 24 min/day (95% CI −41 to −8 min/day, n=3981, moderate quality) and interventions focusing on SB only by 42 min/day (95% CI −79 to −5 min/day, n=62, low quality). There was no evidence of an effect of PA and combined PA/SB interventions on reducing sedentary time. Conclusions: There was evidence that it is possible to intervene to reduce SB in adults. Lifestyle and SB only interventions may be promising approaches. More high quality research is needed to determine if SB interventions are sufficient to produce clinically meaningful and sustainable reductions in sedentary time