Application and refinement of molecular ecology techniques for amphibian conservation

Wildlife conservation has become increasingly difficult due to habitat loss habitat fragmentation and land use change. Thus conservationists have embraced advances in molecular ecology such as landscape genetics and microbial bioinformatics that employ genetic techniques to further understand the relationship between individuals and their environment. In landscape genetics model inferences can be used to identify features that facilitate or resist gene flow providing a framework for anticipating the impacts of land use changes on a species’ ability to disperse. However the factors that affect the transferability of landscape genetics inferences are poorly understood and little is known about the effect of sampling density and study area size on landscape genetics inferences. To address these understudied factors I performed a series of landscape genetics analyses using populations of the Mississippi slimy salamander (Plethodon mississippi) in Mississippi and Alabama. Regional replication revealed the importance of habitat configuration on the relationship between land use and gene flow among salamander populations and the transferability of landscape genetics inferences to neighboring areas. Analysis of hierarchically nested datasets of different sampling densities and study area sizes identified differences due to study area size however no clear effect was seen as a result of different sampling densities. Conservation practitioners can also use microbial ecology to better understand the relationship between wildlife species and their environment. The mutualistic relationship between amphibians and their cutaneous microbial community can strengthen the amphibian’s ability to fight fungal pathogens. However in order to inform management strategies such as probiotic inoculation researchers must first understand the method in which amphibian cutaneous microbiomes are shaped. I compared salamander relatedness salamander cutaneous microbiomes and the microbiomes of salamanders’ immediate soil environment which revealed no relationship between kinship and similarity of skin microbiomes. Further comparison of skin and soil microbiomes provided evidence that the presence of antifungal taxa in a salamander’s environment does not guarantee incorporation of the taxa into salamander cutaneous microbiomes. The results of this research fill knowledge gaps within the fields of landscape genetics and amphibian cutaneous microbial ecology and provide a greater understanding of the relationship between P. mississippi and its environment

The effect of sampling density and study area size on landscape genetics inferences for the Mississippi slimy salamander (Plethodon mississippi)

In landscape genetics, it is largely unknown how choices regarding sampling density and study area size impact inferences upon which habitat features impede vs. facilitate gene flow. While it is recommended that sampling locations be spaced no further apart than the average individual\u27s dispersal distance, for low-mobility species, this could lead to a challenging number of sampling locations, or an unrepresentative study area. We assessed the effects of sampling density and study area size on landscape genetic inferences for a dispersal-limited amphibian, Plethodon mississippi, via analysis of nested datasets. Microsatellite-based genetic distances among individuals were divided into three datasets representing sparse sampling across a large study area, dense sampling across a small study area, or sparse sampling across the same small study area. These datasets were a proxy for gene flow (i.e., the response variable) in maximum-likelihood population effects models that assessed the nature and strength of their relationship with each of five land-use classes (i.e., potential predictor variables). Comparisons of outcomes were based on the rank order of effect, sign of effect (i.e., gene flow resistance vs. facilitation), spatial scale of effect, and functional relationship with gene flow. The best-fit model for each dataset had the same sign of effect for hardwood forests, manmade structures, and pine forests, indicating the impacts of these land-use classes on dispersal and gene flow in P. mississippi are robust to sampling scheme. Contrasting sampling densities led to a different inferred functional relationship between agricultural areas and gene flow. Study area size appeared to influence the scale of effect of manmade structures and the sign of effect of pine forests. Our findings provided evidence for an influence of sampling density, study area size, and sampling effort upon inferences. Accordingly, we recommend iterative subsampling of empirical datasets and continued investigation into the sensitivities of landscape genetic analyses using simulations

Smarter Task Assignment or Greater Effort: the impact of incentives on team performance

We use an experiment to study the impact of team-based incentives, exploiting rich data from personnel records and management information systems. Using a triple difference design, we show that the incentive scheme had an impact on team performance, even with quite large teams. We examine whether this effect was due to increased effort from workers or strategic task reallocation. We find that the provision of financial incentives did raise individual performance but that managers also disproportionately reallocated efficient workers to the incentivised tasks. We show that this reallocation was the more important contributor to the overall outcome.Incentives, Public Sector, Teams, Performance

Finding the "Indian" in Amy Beach's Theme and Variations for Flute and String Quartet, op. 80.

Music that is categorized as part of the Indianist movement in American music (ca. 1890-1925) typically evokes Native American culture, ritual, story, or song through compositional gestures. It may also incorporate Native American tunes. Amy Beach (1867-1944) is considered to have composed five Indianist works, but her Theme and Variations for Flute and String Quartet, op. 80 has not been included as one of them. This thesis rethinks categorization of the piece, seeking the "Indian" in it through examination of its gestures, instrumentation, and relationship to contemporary Indianist compositions

The Impact of Capturing Kids\u27 Hearts on New Teachers’ Perceptions of Classroom Management

The present action research study explored how incorporating the classroom management model of Capturing Kids’ Hearts (CKH) impacted first year teachers’ perceptions of classroom management. The problem of practice indicated first year teachers historically had large numbers of discipline referrals. The guiding questions were 1) What is the impact of Capturing Kids’ Hearts on first-year teachers’ perceptions of classroom management? And 2) How can participant feedback after CKH preparation be used to improve current classroom management policy at BHS? The primary purpose of this action research was to determine the impact of CKH professional development on four first-year teachers’ perceptions of classroom management. The secondary purpose was to enable the new teacher participants to implement innovative ways to manage their classrooms within the policy guidelines at BHS. The tertiary purpose was to enable administrators to improve existing classroom management policies so that they are more conducive to the needs of new teachers. Quantitative data was collected via pre- and postsurveys. New teachers responded to the 21-item survey prior to attending CKH and again after completion of the workshop. Participants included four first-year teachers at a large, suburban high school in central South Carolina. Research findings for this study included: 1. New teachers may not feel confident with classroom management learned solely in pre-service training. Practical strategies and techniques taught by CKH may help improve this finding. Data suggests that CKH improved new teacher’s perception regarding useful strategies and helped to decrease the level of worry regarding classroom management. This can correlate to increased self-efficacy. 2. Although most new teachers understand the importance of relationships, CKH can help teachers see the importance and relevance of building better relationships through the sharing of experiences, and allowing students the opportunity to collaborate with the teacher in the development of social contracts. By improving relationships in this manner, classroom management should improve. An action plan was developed based on the findings of this study

The Association Between Sedentary Behaviors During Weekdays and Weekend with Change in Body Composition in Young Adults

Background: High sedentary time has been considered an important chronic disease risk factor but there is only limited information on the association of specific sedentary behaviors on weekdays and weekend-days with body composition. The present study examines the prospective association of total sedentary time and specific sedentary behaviors during weekdays and the weekend with body composition in young adults. Methods: A total of 332 adults (50% male; 27.7 ±3.7 years) were followed over a period of 1 year. Time spent sedentary, excluding sleep (SED), and in physical activity (PA) during weekdays and weekend-days was objectively assessed every 3 months with a multisensor device over a period of at least 8 days. In addition, participants reported sitting time, TV time and non-work related time spent at the computer separately for weekdays and the weekend. Fat mass and fat free mass were assessed via dual x-ray absorptiometry and used to calculate percent body fat (%BF). Energy intake was estimated based on TDEE and change in body composition. Results: Cross-sectional analyses showed a significant correlation between SED and body composition (0.18 ≤ r ≤ 0.34). Associations between body weight and specific sedentary behaviors were less pronounced and significant during weekdays only (r ≤ 0.16). Nevertheless, decrease in SED during weekends, rather than during weekdays, was significantly associated with subsequent decrease in %BF (β = 0.06, p \u3c0.01). After adjusting for PA and energy intake, results for SED were no longer significant. Only the association between change in sitting time during weekends and subsequent %BF was independent from change in PA or energy intake (β%BF = 0.04, p = 0.01), while there was no significant association between TV or computer time and subsequent body composition. Conclusions: The stronger AIMS Public Health Volume 3, Issue 2, 375-388. prospective association between sedentary behavior during weekends with subsequent body composition emphasizes the importance of leisure time behavior in weight management

The Association Between Sedentary Behaviors During Weekdays and Weekend with Change in Body Composition in Young Adults

Background: High sedentary time has been considered an important chronic disease risk factor but there is only limited information on the association of specific sedentary behaviors on weekdays and weekend-days with body composition. The present study examines the prospective association of total sedentary time and specific sedentary behaviors during weekdays and the weekend with body composition in young adults. Methods: A total of 332 adults (50% male; 27.7 ±3.7 years) were followed over a period of 1 year. Time spent sedentary, excluding sleep (SED), and in physical activity (PA) during weekdays and weekend-days was objectively assessed every 3 months with a multisensor device over a period of at least 8 days. In addition, participants reported sitting time, TV time and non-work related time spent at the computer separately for weekdays and the weekend. Fat mass and fat free mass were assessed via dual x-ray absorptiometry and used to calculate percent body fat (%BF). Energy intake was estimated based on TDEE and change in body composition. Results: Cross-sectional analyses showed a significant correlation between SED and body composition (0.18 ≤ r ≤ 0.34). Associations between body weight and specific sedentary behaviors were less pronounced and significant during weekdays only (r ≤ 0.16). Nevertheless, decrease in SED during weekends, rather than during weekdays, was significantly associated with subsequent decrease in %BF (β = 0.06, p \u3c0.01). After adjusting for PA and energy intake, results for SED were no longer significant. Only the association between change in sitting time during weekends and subsequent %BF was independent from change in PA or energy intake (β%BF = 0.04, p = 0.01), while there was no significant association between TV or computer time and subsequent body composition. Conclusions: The stronger AIMS Public Health Volume 3, Issue 2, 375-388. prospective association between sedentary behavior during weekends with subsequent body composition emphasizes the importance of leisure time behavior in weight management

The many weak instruments problem and Mendelian randomization.

Instrumental variable estimates of causal effects can be biased when using many instruments that are only weakly associated with the exposure. We describe several techniques to reduce this bias and estimate corrected standard errors. We present our findings using a simulation study and an empirical application. For the latter, we estimate the effect of height on lung function, using genetic variants as instruments for height. Our simulation study demonstrates that, using many weak individual variants, two-stage least squares (2SLS) is biased, whereas the limited information maximum likelihood (LIML) and the continuously updating estimator (CUE) are unbiased and have accurate rejection frequencies when standard errors are corrected for the presence of many weak instruments. Our illustrative empirical example uses data on 3631 children from England. We used 180 genetic variants as instruments and compared conventional ordinary least squares estimates with results for the 2SLS, LIML, and CUE instrumental variable estimators using the individual height variants. We further compare these with instrumental variable estimates using an unweighted or weighted allele score as single instruments. In conclusion, the allele scores and CUE gave consistent estimates of the causal effect. In our empirical example, estimates using the allele score were more efficient. CUE with corrected standard errors, however, provides a useful additional statistical tool in applications with many weak instruments. The CUE may be preferred over an allele score if the population weights for the allele score are unknown or when the causal effects of multiple risk factors are estimated jointly.This is the final version. It was first published by Wiley at onlinelibrary.wiley.com/doi/10.1002/sim.6358/abstrac

A home-based exercise intervention to increase physical activity among people living with HIV: study design of a randomized clinical trial

Background While combination antiretroviral therapy has extended the life expectancy of those infected with human immunodeficiency virus (HIV), there is a high prevalence of comorbidities that increase the risk of cardiovascular morbidity and mortality among people living with HIV/AIDS (PLWHA). The side effects associated with antiretroviral therapy (ART) lead to multiple metabolic disorders, making the management of these metabolic issues and risk of cardiovascular disease (CVD) in those treated with ART a critical issue. Clinical research trials, primarily clinical exercise, rarely include this population due to unique challenges in research methods with underserved minority populations living with a life threatening illness like HIV/AIDS. This paper describes the rationale and design of a randomized clinical trial evaluating the feasibility of a home-based exercise program designed to increase physical activity (PA) and reduce the risk of CVD in PLWHA. Methods/design PLWHA being treated with ART will be randomly assigned to one of two groups: a home-based PA intervention or standard care. All participants will receive an educational weight loss workbook and pedometer for self-monitoring of PA. Only those in the intervention group will receive additional elastic Thera-bands® for strength training and behavioral telephone based coaching. Discussion This study will evaluate the feasibility of a home-based program designed to increase PA among PLWHA. Further, it will evaluate the effectiveness of such a program to decrease modifiable risk factors for CVD as a secondary outcome. This study was funded by the NIH/NINR R21 Grant 1R21NRO11281