229 research outputs found
Migration policies and sex selectivity in Kuwait
"November 1990."Includes bibliographical references (leaves 30-33)Research supported by the Social Science Research Council, the Ford Foundation, and the National Endowment for the Humanitie
The Effects of Western Dwarf Mistletoe (Arceuthobium campylopodum) on Radial Growth of Ponderosa Pine (Pinus ponderosa) in Managed Stands in Eastern Oregon
Dwarf mistletoes (Arceuthobium spp.) are native flowering plants that parasitize a range of conifer species throughout western North America. Dwarf mistletoes are considered destructive forest pathogens, but recent research indicates that mistletoes play a key role in structuring plant communities by increasing structural diversity and providing wildlife habitat. The primary objective of my research is to quantify the structural and functional differences between infected and uninfected forest communities.
I investigated the effects of mistletoe (Arceuthobium campylopodum ) on host community dynamics and the interaction between mistletoe infection and fire in old-growth ponderosa pine (Pinus ponderosa) forests. Fifty study plots were established in Crater Lake National Park and Lava Cast Forest, Oregon. I compared fuel composition, broom formation, and flammability between infected and uninfected stands. I also compared mortality rates following prescribed fire treatments and variation in climate response between infected and uninfected trees.
My results indicate that mistletoe increases fine fuel accumulations. It is a weak predictor of fine fuels compared to stand structure measures such as basal area. I also found evidence that infected branches do not persist lower in the crown or live longer than uninfected branches, but it is difficult to accurately age old-growth branches. Prescribed fire results show that plots infected with mistletoe burned at higher temperatures for shorter periods than uninfected plots. There is no difference in fuel reduction between the two groups. Post-fire mortality rate was 35%, but there was no difference in mortality between uninfected and infected plots. Burn chamber tests indicate that infected branches lost a greater proportion of their mass during burns, primarily as needle combustion. Results from the climate response study show that mature trees infected with dwarf mistletoe have higher radial growth rates, exhibit greater sensitivity, and respond more strongly to climate variation. The results of this work indicate that the influence of dwarf mistletoe on ponderosa pine fire ecology is complex and often indirect. My results suggest that managers should consider mistletoe abundance when modeling fire behavior in unmanaged ponderosa pine stands, but do not need to consider different prescriptions for fire treatments in intensively managed stands
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Multi-year school-based implementation and student outcomes of an evidence-based risk reduction intervention
Background Intervention effects observed in efficacy trials are rarely replicated when the interventions are broadly disseminated, underscoring the need for more information about factors influencing real-life implementation and program impact. Using data from the ongoing national implementation of an evidence-based HIV prevention program [Focus on Youth in The Caribbean (FOYC)] in The Bahamas, this study examines factors influencing teachers’ patterns of implementation, the impact of teachers’ initial implementation of FOYC, and subsequent delivery of the booster sessions on students’ outcomes. Methods Data were collected from the 80 government elementary and 34 middle schools between 2011 and 2014, involving 208 grade 6, 75 grade 7, and 58 grade 8 teachers and 4411 students initially in grade 6 and followed for 3 years. Student outcomes include HIV/AIDS knowledge, reproductive health skills, self-efficacy, and intention to use protection. Data from teachers includes implementation and modification of the curriculum, attitudes towards the prevention program, comfort level with the curriculum, and attendance at training workshops. Structural equation modeling and mixed-effect modeling analyses were applied to examine the impact of teachers’ implementation. Results Teachers’ attitudes towards and comfort with the intervention curriculum, and attendance at the curriculum training workshop had a direct effect on teachers’ patterns of implementation, which had a direct effect on student outcomes. Teachers’ attitudes had a direct positive effect on student outcomes. Teachers’ training in interactive teaching methods and longer duration as teachers were positively associated with teachers’ comfort with the curriculum. High-quality implementation in grade 6 was significantly related to student outcomes in grades 6 and 7 post-implementation. Level of implementation of the booster sessions in grades 7 and 8 were likewise significantly related to subsequent student outcomes in both grades. Conclusions High-quality initial implementation of a prevention program is significantly related to better program outcomes. Poor subsequent delivery of booster sessions can undermine the positive effects from the initial implementation while strong subsequent delivery of booster sessions can partially overcome poor initial implementation
Fostering community engagement, participation and empowerment for mental health of adults living in rural communities: a systematic review
Introduction: Poor mental health is an under-recognised burden in rural locations. This is evident in suicide rates that are 40% higher in rural communities than in urban ones, despite a similar prevalence of mental disorders. The level of readiness and engagement of rural communities to adapt or even acknowledge poor mental health can impact effective interventions. For interventions to be culturally appropriate, community engagement should include individuals, their support networks and relevant stakeholders. Community participation guides people living in rural communities to be aware of and take responsibility for community mental health. Community engagement and participation foster empowerment. This review examines how community engagement, participation and empowerment were used in the development and implementation of interventions aimed at improving mental health of adults residing in rural communities.
Methods: Databases CINAHL, EmCare, Google Scholar, Medline, PsychInfo, PubMed and Scopus were systematically searched from database inception to July 2021. Eligible studies included adults living in a rural cohort where community engagement was used to develop and implement a mental health intervention.
Results: From 1841 records identified, six met the inclusion criteria. Methods were both qualitative and quantitative, including participatory-based research, exploratory descriptive research, community-built approach, community-based initiative and participatory appraisal. Studies were located in rural communities of the USA, UK and Guatemala. Sample size ranges was 6-449 participants. Participants were recruited using prior relationships, project steering committee, local research assistants and local health professionals. All six studies underwent various strategies of community engagement and participation. Only two articles progressed to community empowerment where locals influenced one another independently. The underlying purpose of each study was to improve community mental health. The duration of the interventions ranged from 5 months to 3 years. Studies on the early stages of community engagement discovered a need to address community mental health. Studies where interventions were implemented resulted in improved community mental health.
Conclusion: This systematic review found similarities in community engagement when developing and implementing interventions for community mental health. Community engagement should involve adults residing in rural communities when developing interventions - if possible, both with a diverse gender representation and a background in health. Community participation can include upskilling adults living in rural communities and providing appropriate training materials to do so. Community empowerment was achieved when the initial contact with rural communities was through local authorities and there was support from community management. Future use of the strategies of engagement, participation and empowerment could determine if they can be replicated across rural communities for mental health
Bahamas National Implementation Project: Proposal for Sustainability of an Evidence-based HIV Prevention Intervention in a School Setting
BACKGROUND: Sustained implementation of school-based prevention programs is low. Effective strategies are needed to enhance both high-level implementation fidelity and sustainability of prevention programs.
OBJECTIVE: This proposed study aims to determine if the provision of either biweekly monitoring and feedback and site-based assistance and mentorship or both to at-risk and moderate-performing teachers with monitoring through an enhanced decision-making platform by the Ministry of Education (MOE) and Ministry of Health (MOH) based on the real-time implementation data will increase national implementation fidelity and result in sustained implementation over time.
METHODS: This study will target government schools including 200 grade 6 teachers in 80 primary schools and 100 junior/middle high school teachers (and their classes) on 12 Bahamian islands. Teacher and school coordinator training will be conducted by the MOE in year 1, followed by an optimization trial among teachers in the capital island. Informed by these results, an implementation intervention will be conducted to train using different levels of educational intensity all at-risk and moderate-performing teachers. Subsequently selected training and implementation strategies will be evaluated for the national implementation of Focus on Youth in the Caribbean and Caribbean Informed Parents and Children Together in years 2 to 5.
RESULTS: It is hypothesized that a more intensive training and supervision program for at-risk and moderate-performing teachers will enhance their implementation fidelity to the average level of the high-performing group (85%), an HIV prevention program delivered at the national level can be implemented with fidelity in grade 6 and sustained over time (monitored annually), and student outcomes will continue to be highly correlated with implementation fidelity and be sustained over time (assessed annually through grade 9). The proposed study is funded by the National Institute of Child Health and Human Development from August 1, 2018, through May 31, 2023.
CONCLUSIONS: The study will explore several theory-driven implementation strategies to increase sustained teacher implementation fidelity and thereby increase the general public health impact of evidence-based interventions. The proposed project has potential to make significant contributions to advancing school-based HIV prevention research and implementation science and serve as a global model for the Fast Track strategy.
INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/14816. Xiaoming Li, Sharon Marshall, Glenda Rolle, Nikkiah Forbes, Bonita Stanton. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 21.08.2020
Factors influencing implementation dose and fidelity thereof and related student outcomes of an evidence-based national HIV prevention program
When Things Are Not as They Appear: Assessing the Adequacy of Cluster Randomization When Outcome Events Are Rare at Baseline
The present study randomly assigned 15 Bahamian elementary schools to one of three intervention conditions. To assess the adequacy of cluster randomization, we examined two concerns identified by the local research team: inequality of gender distribution and environmental risk among groups. Baseline significant differences in risk and protective behaviors were minimal. There were significantly more males in the intervention group. Males had higher rates of risk behavior at all assessments. Poor school performance was also higher among the intervention condition and was significantly associated with increased rates of many but not all risk behaviors. Prior to adjusting for gender and school performance, several risk behaviors appeared to be higher after intervention among intervention youth. Adjusting for gender and school performance eradicated the group differences in risk behavior rates. Results demonstrate the importance of adequate randomization where outcomes of interest are rare events at baseline or differ by gender and there is an unequal gender distribution and the importance of the local research team's knowledge of potential inequalities in environmental risk (i.e., school performance). Not considering such individual differences could impact the integrity of trial outcomes
Healthy eating and lifestyle in pregnancy (HELP): a cluster randomised trial to evaluate the effectiveness of a weight management intervention for pregnant women with obesity on weight at 12 months postpartum
Objective: To assess whether a weight management intervention for pregnant women with obesity was effective in reducing body mass index (BMI) 12 months after giving birth. Methods: Pragmatic, cluster randomised controlled trial (RCT) with embedded cost-effectiveness analysis. 598 women with a BMI of ≥30 kg/m2 (between 12 and 20 weeks gestation) were recruited from 20 secondary care maternity units in England and Wales. BMI at 12 months postpartum was the primary outcome. A range of clinical and behavioural secondary outcomes were examined. Interventions: Women attending maternity units randomised to intervention were invited to a weekly weight management group, which combined expertise from a commercial weight loss programme with clinical advice from midwives. Both intervention and control participants received usual care and leaflets on diet and physical activity in pregnancy. Results: Mean (SD) BMI at 12 months postpartum was 36.0 kg/m2 (5.2) in the control group, and 37.5 kg/m2 (6.7) in the intervention group. After adjustment for baseline BMI, the intervention effect was −0.02 (95% CI −0.04 to 0.01). The intervention group had an improved healthy eating score (3.08, 95% CI 0.16 to 6.00, p < 0.04), improved fibre score (3.22, 1.07 to 5.37, p < 0.01) and lower levels of risky drinking at 12 months postpartum compared to the control group (OR 0.45, 0.27 to 0.74, p < 0.002). The net incremental monetary benefit was not statistically significantly different between arms, although the probability of the intervention being cost-effective was above 60%, at policy-relevant thresholds. Conclusions: There was no significant difference between groups on the primary outcome of BMI at 12 months. Analyses of secondary outcomes indicated improved healthy eating and lower levels of risky drinking. Trial registration: Current Controlled Trials ISRCTN25260464
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