The effect of viewing time, time to encounter, and practice on perception of aircraft separation on a cockpit display of traffic information

The concept of a cockpit display of traffic information (CDTI) includes the integration of air traffic, navigation, and other pertinent information in a single electronic display in the cockpit. Two studies were conducted to develop a clear and concise display format for use in later full-mission simulator evaluations of the CDTI concept. Subjects were required to monitor a CDTI for specified periods of time and to make perceptual judgments concerning the future position of a single intruder aircraft in relationship to their own aircraft. Experimental variables included: type of predictor information displayed on the two aircraft symbols; time to encounter point; length of time subjects viewed the display; amount of practice; and type of encounter (straight or turning). Results show that length of viewing time had little or no effect on performance; time to encounter influenced performance with the straight predictor but did not with the curved predictor; and that learning occurred under all conditions

Physical activity and sedentary behaviours in Greek-Cypriot children and adolescents: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>There are no data on physical activity and sedentary behaviours of Greek-Cypriot children and adolescents, and no study to date examined the association between these two behaviours in this population. The purpose of this study was to document the prevalence of physical activity and sedentary behaviours among Greek-Cypriot adolescents and examine the association between physical activity and a range of sedentary behaviours. Logistic regression analyses were performed to examine the association between physical activity and sedentary behaviours.</p> <p>Methods</p> <p>A cross-sectional study among 1,966 Greek-Cypriot children and adolescents was conducted in 2008/2009. Data were collected by means of a questionnaire across primary, middle, high and technical/vocational schools.</p> <p>Results</p> <p>Overall 52.3% and 52.4% of the participants met physical activity and television viewing guidelines respectively. Boys and younger children were more likely to meet guidelines. Boys who attended sports clubs for two or more times per week were more likely to be physically active (OR = 3.4), and those who listened to music for one or less than one hour per day were less likely to be physically active (OR = 0.6). Girls who attended sports clubs for two or more times per week and who watched television for two or less than two hours per day were more likely to be physically active, (OR = 3.0 and OR = 1.5 respectively). Girls who reported travelling by car/bus/motorbike for one or less than one hour per day were more likely to actively travel to school (OR = 1.8).</p> <p>Conclusions</p> <p>Findings from this study provide limited support for the displacement hypothesis whereby sedentary behaviours displace physically active time. About 50.0% of Greek children and adolescents in Cyprus meet existing physical activity and television viewing guidelines. Encouraging children to attend sports clubs for at least two times per week may markedly improve their physical activity levels.</p

Ultrafast Momentum Imaging of Pseudospin-Flip Excitations in Graphene

The pseudospin of Dirac electrons in graphene manifests itself in a peculiar momentum anisotropy for photo-excited electron-hole pairs. These interband excitations are in fact forbidden along the direction of the light polarization, and are maximum perpendicular to it. Here, we use time- and angle-resolved photoemission spectroscopy to investigate the resulting unconventional hot carrier dynamics, sampling carrier distributions as a function of energy and in-plane momentum. We first show that the rapidly-established quasi-thermal electron distribution initially exhibits an azimuth-dependent temperature, consistent with relaxation through collinear electron-electron scattering. Azimuthal thermalization is found to occur only at longer time delays, at a rate that depends on the substrate and the static doping level. Further, we observe pronounced differences in the electron and hole dynamics in n-doped samples. By simulating the Coulomb- and phonon-mediated carrier dynamics we are able to disentangle the influence of excitation fluence, screening, and doping, and develop a microscopic picture of the carrier dynamics in photo-excited graphene. Our results clarify new aspects of hot carrier dynamics that are unique to Dirac materials, with relevance for photo-control experiments and optoelectronic device applications.Comment: 23 pages, 12 figure

A qualitative exploration of English black adults’ views of strength and balance activities in mid-life

BACKGROUND: Public health guidelines state that all adults should undertake muscle and bone strengthening and balance training activities at least twice a week to support their physical function and maintain independent health. This is intended to maintain strength in adulthood and offset natural declines in bone density and muscle mass. Most older adults do not meet this guideline with low levels of compliance among older black people. This study explored the experiences of physical activity relating to strength and balance activities, amongst black men and women living in England, aged 50–70. METHODS: Participants were recruited by phone via a network of research recruitment specialists across England. In-depth qualitative interviews were conducted with 25 black people aged 50–70 living in England. An inductive thematic analysis was conducted. RESULTS: We found there was only a very general understanding of the importance of maintaining body strength and balance, and low salience: strength and balance activities were not seen to be an important part of participants’ lives. Most participants only wanted to be strong enough to get on with ‘normal life’ and not to build strength or balance. Participants aged 50–70 were likely to think they were too young to worry about strength and balance, which tended to be mentioned only if someone had experienced a problem. Participants reported that NHS staff, especially physiotherapists are a key source of information on the topic and could therefore be useful in future prevention strategies. CONCLUSION: Public health recommendations stress the importance of increasing participation in regular strength and balance activities as people age, to reduce the risk of falls and maintain independence. This study has shown that among the black middle-aged adults we interviewed, the knowledge and salience of this message is low. Public health approaches should be taken to communicate the importance of enhancing strength and balance as people approach older age, including communication and education programmes led by health professionals, who were viewed with authority amongst these participants

Associations between physical activity parenting practices and adolescent girls’ self-9 perceptions and physical activity intentions

Background: The present study investigated cross-sectional associations between maternal and paternal logistic and modelling physical activity support and the self-efficacy, self-esteem and physical activity intentions of 11-12 year old girls. Method: 210 girls reported perceptions of maternal and paternal logistic and modelling support and their self-efficacy, self-esteem and intention to be physically active. Data were analysed using multivariable regression models. Results: Maternal logistic support was positively associated with participants’ self-esteem, physical activity self-efficacy and intention to be active. Maternal modelling was positively associated with self-efficacy. Paternal modelling was positively associated with self-esteem and self-efficacy but there was no evidence that paternal logistic support was associated with the psychosocial variables. Conclusions: Activity-related parenting practices were associated with psychosocial correlates of physical activity among adolescent girls. Logistic support from mothers, rather than modelling support or paternal support may be a particularly important target when designing interventions aimed at preventing the age-related decline in physical activity among girls

Action 3:30R: Process evaluation of a cluster randomised feasibility study of a revised teaching assistant-led extracurricular physical activity intervention for 8 to 10 year olds

Background: Numerous interventions to increase children's physical activity levels are published, yet, few studies report indicators of external validity. Process evaluations are critical for assessing intervention implementation, sustainability and effectiveness. A mixed-methods process evaluation, using the RE-AIM framework, was conducted to evaluate the internal and external validity of Action 3:30R, a revised teaching assistant-led after-school intervention which aimed to increase physical activity in children aged 8-10 years and was underpinned by Self-determination Theory (SDT). Methods: Data were collected and reported in line with the five components of RE-AIM (Reach, Effectiveness, Adoption, Implementation and Maintenance). Quantitative measures included logbooks, registers and self-reported teaching-efficacy, autonomy support, child enjoyment and perceived exertion questionnaires. Questionnaire data were collected at three points throughout the 15-week intervention. Observations by trained researchers were also conducted to assess fidelity to the intervention manual and its underpinning theory. Post-intervention focus groups with pupils and interviews with teaching assistants (TAs), school staff and external stakeholders explored the implementation and potential sustainability of Action 3:30R from stakeholders' perspectives. Results: Action 3:30R appealed to a broad range of pupils, including girls and less-active pupils. The Action 3:30R TA training was implemented as intended and was perceived as valuable professional development. Releasing staff for training was a barrier in two of the six intervention schools, which were unable to deliver the intervention as a result. Pupils enjoyed the intervention, and the Action 3:30R core principles underpinned by SDT were implemented with high fidelity, as was the intervention itself. Scheduling conflicts with other clubs and lack of parental support were perceived as the main barriers to recruitment and attendance. Lack of space and season were cited as the main barriers affecting the quality of delivery. The study shows evidence of maintenance, as one intervention school decided to continue Action 3:30R beyond the study. Funding and continued TA training were suggested as factors which may affect the maintenance of Action 3:30R. Conclusions: Action 3:30R is an enjoyable, autonomy-supportive after-school programme, which engages a range of pupils and offers TAs valuable training. RE-AIM provided helpful structure and is recommended for intervention evaluations. Trial registration: ISRCTN34001941. Prospectively registered 01/12/2016

Examining a conceptual model of parental nurturance, parenting practices and physical activity among 5-6 year olds

AbstractRationaleParenting is an often-studied correlate of children's physical activity, however there is little research examining the associations between parenting styles, practices and the physical activity of younger children.ObjectiveThis study aimed to investigate whether physical activity-based parenting practices mediate the association between parenting styles and 5–6 year-old children's objectively-assessed physical activity.Methods770 parents self-reported parenting style (nurturance and control) and physical activity-based parenting practices (logistic and modeling support). Their 5–6 year old child wore an accelerometer for five days to measure moderate-to-vigorous physical activity (MVPA). Linear regression was used to examine direct and indirect (mediation) associations. Data were collected in the United Kingdom in 2012/13 and analyzed in 2014.ResultsParent nurturance was positively associated with provision of modeling (adjusted unstandardized coefficient, β = 0.11; 95% CI = 0.02, 0.21) and logistic support (β = 0.14; 0.07, 0.21). Modeling support was associated with greater child MVPA (β = 2.41; 0.23, 4.60) and a small indirect path from parent nurturance to child's MVPA was identified (β = 0.27; 0.04, 0.70).ConclusionsPhysical activity-based parenting practices are more strongly associated with 5–6 year old children's MVPA than parenting styles. Further research examining conceptual models of parenting is needed to understand in more depth the possible antecedents to adaptive parenting practices beyond parenting styles

Poly[3-methyl­pyridinium [(μ2-di­hydrogen phosphito)bis­(μ3-hydrogen phosphito)dizinc]]

Peer reviewe

Sexual exploitation in children: Nature, prevalence and distinguishing characteristics reported in young adulthood

The aim of this study was to explore the nature and extent of sexual exploitation in a university student sample, whilst being clear that sexual exploitation is sexual abuse. Overall, 47% of participants (96 out of 204) reported having been approached by an adult in a sexual manner when they were under the age of 16. The study predicted that a number of individual characteristics would increase a young person’s vulnerability for sexual exploitation. These included low self-esteem, external locus of control, social loneliness and insecure attachment. Results indicated lower levels of self-esteem among those who had been approached sexually, although it is not clear in terms of causality. There were no differences in scores for locus of control or loneliness. Relationship anxiety was significantly linked with children having engaged in sexual behaviours with an adult. The implications of these findings are discussed in terms of emerging individual characteristics relating to a risk of sexual exploitation