278 research outputs found

    Forest Development over a Twenty-Year Chronosequence of Reforested Urban Sites

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    Urbanization causes a variety of negative ecological impacts, impairing forests, streams, and other ecosystems. While urban forests are the subject of increasing research attention, planted urban forests are less well-understood than remnant forests; however, these systems may be distinct in terms of ecosystem structure and function. The current study investigates a chronosequence of reforested urban sites in Lexington, KY, USA, with a focus on overstory and understory woody plant community characteristics. Monitoring plots were established in each of the 20 sites; tree height, dbh, and species were surveyed for the overstory, and species and height were surveyed for the understory. Canopy height increased non-linearly with time since planting, rapidly increasing in years 6–10, but remaining relatively steady after year 15. While the overstory was dominated by planted native species, the understory was predominately non-native species, some of which are considered invasive. Overall, the nonlinear logistic relationship of canopy height to time since planting may be driven by species-specific effects—with trees such as ash (Fraxinus spp. L.) and black locust (Robinia pseudoacacia L.) important during the early years after planting, but declining over time due to pests and other pressures. Alternatively, this complex relationship of canopy height with time may be driven by uncontrolled factors such as site quality, landscape position, planted species, etc. The significance of invasive species in the understory suggests that the long-term health of these sites will be compromised without intentional ongoing maintenance to ensure continued forest development toward desired native community characteristics

    Physical Examination is the Best Predictor of the Need for Abdominal Surgery in Children Following Motor Vehicle Collision

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    BACKGROUND: Exploratory laparotomy in children after motor vehicle collision (MVC) is rare. In the absence of definitive hemorrhage or free abdominal air on radiographic imaging, predictors for operative exploration are conflicting. OBJECTIVE: The purpose of this study was to explore objective findings that may aid in determining which children require operative abdominal exploration after MVC. METHODS: Data from 2010-2014 at an American College of Surgeons-certified level 1 pediatric trauma center were retrospectively reviewed. Demographics, vital signs, laboratory data, radiologic studies, operative records, associated injuries, and outcomes were analyzed and p < 0.05 was considered statistically significant. RESULTS: Eight hundred sixty-two patients 0-18 years of age presented to the hospital after an MVC during the study period. Seventeen patients (2.0%) required abdominal exploration and all were found to have intraabdominal injuries. Respiratory rate was the only vital sign that was significantly altered (p = 0.04) in those who required abdominal surgery compared with those who did not. Physical examination findings, such as the seat belt sign, abdominal bruising, abdominal wound, and abdominal tenderness, were present significantly more frequently in those requiring abdominal surgery (p < 0.0001). Each finding had a negative predictive value for the need for operative exploration of at least 0.98. There were no significant differences in trauma laboratory values or radiographic findings between the 2 groups. CONCLUSION: Data from this study solidify the relationship between specific physical examination findings and the need for abdominal exploration after MVC in children. In addition, these data suggest that a lack of the seat belt sign, abdominal bruising, abdominal wounds, or abdominal tenderness are individually predictive of patients who will not require surgical intervention

    Coleman - de Luccia instanton of the second order in a brane world

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    The second order Coleman - de Luccia instanton and its action in the Randall - Sundrum type II model are investigated and the comparison with the results in Einstein's general relativity is done in the present paper.Comment: 4 pages, accepted in IJT

    General Aviation Weather Encounter Case Studies

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    This study presents a compilation of 24 cases involving general aviation (GA) pilots’ weather encounters over the continental U.S. The project team interviewed pilots who had experienced a weather encounter, and we examined their backgrounds, flight experience, and weather encounter details. Results from meteorological data analysis for each weather encounter were consistent with findings of larger GA weather accident studies in terms of the types of hazards encountered and flight phase during which the encounters occurred. Investigation of pilot weather products and the sources from which they were obtained revealed a lack of uniformity of pre-flight data sources and underutilization of available en route flight information services. The team used these results to develop a set of pilot weather education and training recommendations intended to reduce the number and severity of weather encounters

    Impact of a brief group intervention to enhance parenting and the home learning environment for children aged 6-36 months: A cluster randomised controlled trial

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    This is the final version of the article. Available from the publisher via the DOI in this record.This study evaluated the effectiveness of a group parenting intervention designed to strengthen the home learning environment of children from disadvantaged families. Two cluster randomised controlled superiority trials were conducted in parallel and delivered within existing services: a 6-week parenting group (51 locations randomised; 986 parents) for parents of infants (aged 6-12 months), and a 10-week facilitated playgroup (58 locations randomised; 1200 parents) for parents of toddlers (aged 12-36 months). Each trial had three conditions: intervention (smalltalk group-only); enhanced intervention with home coaching (smalltalk plus); and 'standard'/usual practice controls. Parent-report and observational measures were collected at baseline, 12 and 32 weeks follow-up. Primary outcomes were parent verbal responsivity and home learning activities at 32 weeks. In the infant trial, there were no differences by trial arm for the primary outcomes at 32 weeks. In the toddler trial at 32-weeks, participants in the smalltalk group-only trial showed improvement compared to the standard program for parent verbal responsivity (effect size (ES) = 0.16; 95% CI 0.01, 0.36) and home learning activities (ES = 0.17; 95% CI 0.01, 0.38) but smalltalk plus did not. For the secondary outcomes in the infant trial, several initial differences favouring smalltalk plus were evident at 12 weeks, but not maintained to 32 weeks. For the toddler trial, differences in secondary outcomes favouring smalltalk plus were evident at 12 weeks and maintained to 32 weeks. These trials provide some evidence of the benefits of a parenting intervention focused on the home learning environment for parents of toddlers but not infants. TRIAL REGISTRATION: 8 September 2011; ACTRN12611000965909 .This research was commissioned and funded by the Victorian Government Department of Education and Early Childhood Development (DEECD), and designed and conducted at the Parenting Research Centre. NH, EW, SB, AS, MT, MY and JN were employees of the Parenting Research Centre when this study was conducted. EW was part-funded by the Centre for Research Excellence in Child Language at Murdoch Childrens Research Institute (NHMRC grant 1023493). NH, EW, SB and JN are funded by the Australian Communities Foundation (Coronella sub-fund) at La Trobe University. OU is supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula at the Royal Devon and Exeter NHS Foundation Trust. Views expressed are those of the authors and not necessarily those of DEECD, NIHR, NHS or the Department of Health

    Enhancing the early home learning environment through a brief group parenting intervention: study protocol for a cluster randomised controlled trial.

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    BACKGROUND: The quality of the home learning environment has a significant influence on children's language and communication skills during the early years with children from disadvantaged families disproportionately affected. This paper describes the protocol and participant baseline characteristics of a community-based effectiveness study. It evaluates the effects of 'smalltalk', a brief group parenting intervention (with or without home coaching) on the quality of the early childhood home learning environment. METHODS/DESIGN: The study comprises two cluster randomised controlled superiority trials (one for infants and one for toddlers) designed and conducted in parallel. In 20 local government areas (LGAs) in Victoria, Australia, six locations (clusters) were randomised to one of three conditions: standard care (control); smalltalk group-only program; or smalltalk plus (group program plus home coaching). Programs were delivered to parents experiencing socioeconomic disadvantage through two existing age-based services, the maternal and child health service (infant program, ages 6-12 months), and facilitated playgroups (toddler program, ages 12-36 months). Outcomes were assessed by parent report and direct observation at baseline (0 weeks), post-intervention (12 weeks) and follow-up (32 weeks). Primary outcomes were parent verbal responsivity and home activities with child at 32 weeks. Secondary outcomes included parenting confidence, parent wellbeing and children's communication, socio-emotional and general development skills. Analyses will use intention-to-treat random effects ("multilevel") models to account for clustering. RECRUITMENT AND BASELINE DATA: Across the 20 LGAs, 986 parents of infants and 1200 parents of toddlers enrolled and completed baseline measures. Eighty four percent of families demonstrated one or more of the targeted risk factors for poor child development (low income; receives government benefits; single, socially isolated or young parent; culturally or linguistically diverse background). DISCUSSION: This study will provide unique data on the effectiveness of a brief group parenting intervention for enhancing the early home learning environment of young children from disadvantaged families. It will also provide evidence of the extent to which additional one-on-one support is required to achieve change and whether there are greater benefits when delivered in the 1st year of life or later. The program has been designed for scale-up across existing early childhood services if proven effective. TRIAL REGISTRATION: 8 September 2011; ACTRN12611000965909 .This research was commissioned and funded by the Victorian Government Department of Education and Early Childhood (now the Department of Education and Training, DET). JN, MT, SB, TH, VH, EW and NH were employees of the Parenting Research Centre when this study was designed and conducted. JN, SB, EW & NH are currently supported by the Australian Communities Foundation through the Roberta Holmes Transition to Contemporary Parenthood Program (Coronella sub-fund); EW was part-funded by the Centre for Research Excellence in Child Language at Murdoch Children’s Research Institute (NHMRC grant 1023493). OU is funded by the UK National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) for the South West Peninsula at the Royal Devon and Exeter NHS Foundation Trust. The views expressed in this publication are those of the authors and not necessarily those of the funding bodies

    The Skyrme Energy Functional and Naturalness

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    Recent studies show that successful relativistic mean-field models of nuclei are consistent with naive dimensional analysis and naturalness, as expected in low-energy effective field theories of quantum chromodynamics. The nonrelativistic Skyrme energy functional is found to have similar characteristics.Comment: 8 pages, REVTeX 3.0 with epsf.sty, plus 2 figure

    The agreement between parent-reported and directly measured child language and parenting behaviors

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    Parenting behaviors are commonly targeted in early interventions to improve children\u27s language development. Accurate measurement of both parenting behaviors and children\u27s language outcomes is thus crucial for sensitive assessment of intervention outcomes. To date, only a small number of studies have compared parent-reported and directly measured behaviors, and these have been hampered by small sample sizes and inaccurate statistical techniques, such as correlations. The Bland-Altman Method and Reduced Major Axis regression represent more reliable alternatives because they allow us to quantify fixed and proportional bias between measures. In this study, we draw on data from two Australian early childhood cohorts (N = 201 parents and slow-to-talk toddlers aged 24 months; and N = 218 parents and children aged 6-36 months experiencing social adversity) to (1) examine agreement and quantify bias between parent-reported and direct measures, and (2) to determine socio-demographic predictors of the differences between parent-reported and direct measures. Measures of child language and parenting behaviors were collected from parents and their children. Our findings support the utility of the Bland-Altman Method and Reduced Major Axis regression in comparing measurement methods. Results indicated stronger agreement between parent-reported and directly measured child language, and poorer agreement between measures of parenting behaviors. Child age was associated with difference scores for child language; however, the direction varied for each cohort. Parents who rated their child\u27s temperament as more difficult tended to report lower language scores on the parent questionnaire, compared to the directly measured scores. Older parents tended to report lower parenting responsiveness on the parent questionnaire, compared to directly measured scores. Finally, speaking a language other than English was associated with less responsive parenting behaviors on the videotaped observation compared to the parent questionnaire. Variation in patterns of agreement across the distribution of scores highlighted the importance of assessing agreement comprehensively, providing strong evidence that simple correlations are grossly insufficient for method comparisons. We discuss implications for researchers and clinicians, including guidance for measurement selection, and the potential to reduce financial and time-related expenses and improve data quality. Further research is required to determine whether findings described here are reflected in more representative populations
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