Preliminary Study of Pesticide Drift into the Maya Mountain Protected Areas of Belize

In Belize, Central America, many farms surrounding the Protected Areas of the Maya Mountains rely heavily on the application of agrochemicals. The purpose of this study was to test whether orographic drift of glyphosate and organophosphates into the nearby Maya Mountain Protected Areas occurred by collecting phytotelmic water from seven sites over 3 years. Regardless of location within the Maya Mountain Protected Areas, glyphosate was present; organophosphates were more common at ridge sites. Although glyphosate concentrations were low, due to the number of threatened species and the human use of stream water outside the Maya Mountain Protected Areas, better understanding of these effects is warranted

Finite element methods for the incompressible Stokes equations with variable viscosity

Finite element error estimates are derived for the incompressible Stokes equations with variable viscosity. The ratio of the supremum and the infimum of the viscosity appears in the error bounds. Numerical studies show that this ratio can be observed sometimes. However, often the numerical results show a weaker dependency on the viscosity

Employer Reports of Skills Gaps in the Workforce

Skills gaps in the workforce are a common conversation in the current value proposition of higher education. Colleges are expected to help students prepare for a world-class workforce while maintaining the integrity of the academic mission. Employers have similar but different opinions on the preparation of college graduates. This exploratory study took an in-depth look at the perceptions of sixteen employers in a region of the Midwest on questions about the perception of hiring managers about the skills gap in the workforce. Questions focused on work readiness, common challenges, and opportunities that exist to combat these hiring challenges. The themes that emerged from the study provide a foundation for future research with employers and conversations on skills gap in addition to providing guidance to colleges. Five themes emerged from the study: corporate strategy, role of the university, experience, applicant skills, and career management. Recommendations include developing formal relationships between the employer and the university, supporting lifelong learning for new hires, hiring based on the potential for learning and offering more internships. The participants presented ideas and suggestions for best practices and noted how to best connect students to opportunities. Advisor: Marilyn Grad

Batrachochytrium dendrobatidis Shows High Genetic Diversity and Ecological Niche Specificity among Haplotypes in the Maya Mountains of Belize

The amphibian pathogen Batrachochytrium dendrobatidis (Bd) has been implicated in amphibian declines around the globe. Although it has been found in most countries in Central America, its presence has never been assessed in Belize. We set out to determine the range, prevalence, and diversity of Bd using quantitative PCR (qPCR) and sequencing of a portion of the 5.8 s and ITS1-2 regions. Swabs were collected from 524 amphibians of at least 26 species in the protected areas of the Maya Mountains of Belize. We sequenced a subset of 72 samples that had tested positive for Bd by qPCR at least once; 30 samples were verified as Bd. Eight unique Bd haplotypes were identified in the Maya Mountains, five of which were previously undescribed. We identified unique ecological niches for the two most broadly distributed haplotypes. Combined with data showing differing virulence shown in different strains in other studies, the 5.8 s - ITS1-2 region diversity found in this study suggests that there may be substantial differences among populations or haplotypes. Future work should focus on whether specific haplotypes for other genomic regions and possibly pathogenicity can be associated with haplotypes at this locus, as well as the integration of molecular tools with other ecological tools to elucidate the ecology and pathogenicity of Bd

Physiological, biochemical, anthropometric and biomechanical influences on exercise economy in humans

Inter-individual variation in running and cycling exercise economy (EE) remains unexplained although studied for more than a century. This study is the first to comprehensively evaluate the importance of biochemical, structural, physiological, anthropometric, and biomechanical influences on running and cycling EE within a single study. In 22 healthy males (VO2 max range 45.5 to 72.1 ml.min(-1) .kg(-1) ) no factor related to skeletal muscle structure (% slow twitch fibre content, number of capillaries per fibre), mitochondrial properties (volume density, oxidative capacity, or mitochondrial efficiency) or protein content (UCP3 and MFN2 expression) explained variation in cycling and running EE among subjects. In contrast, biomechanical variables related to vertical displacement correlated well with running EE, but were not significant when taking body weight into account. Thus, running EE and body weight were correlated (R(2) = 0.94; P < 0.001), but was lower for cycling EE (R(2) = 0.23; P < 0.023). To separate biomechanical determinants of running EE we contrasted individual running and cycling EE considering that during cycle ergometer exercise the biomechanical influence on EE would be small because of the fixed movement pattern. Differences in cycling and running exercise protocols, e.g., related to biomechanics, play however only a secondary role in determining EE. There was no evidence for an impact of structural or functional skeletal muscle variables on EE. Body weight was the main determinant of EE explaining 94% of variance in running EE, although more than 50% of the variability of cycling EE remains unexplained

Offspring Hormones Reflect the Maternal Prenatal Social Environment: Potential for Foetal Programming?

Females of many species adaptively program their offspring to predictable environmental conditions, a process that is often mediated by hormones. Laboratory studies have shown, for instance, that social density affects levels of maternal cortisol and testosterone, leading to fitness-relevant changes in offspring physiology and behaviour. However, the effects of social density remain poorly understood in natural populations due to the difficulty of disentangling confounding influences such as climatic variation and food availability. Colonially breeding marine mammals offer a unique opportunity to study maternal effects in response to variable colony densities under similar ecological conditions. We therefore quantified maternal and offspring hormone levels in 84 Antarctic fur seals (Arctocephalus gazella) from two closely neighbouring colonies of contrasting density. Hair samples were used as they integrate hormone levels over several weeks or months and therefore represent in utero conditions during foetal development. We found significantly higher levels of cortisol and testosterone (both P < 0.001) in mothers from the high density colony, reflecting a more stressful and competitive environment. In addition, offspring testosterone showed a significant positive correlation with maternal cortisol (P < 0.05). Although further work is needed to elucidate the potential consequences for offspring fitness, these findings raise the intriguing possibility that adaptive foetal programming might occur in fur seals in response to the maternal social environment. They also lend support to the idea that hormonally mediated maternal effects may depend more strongly on the maternal regulation of androgen rather than cortisol levels

Evaluation of a Long-Term Amphibian Monitoring Protocol in Central America

The Maya Forest Monitoring Project (Mayamon) was established in 1997 as an outgrowth of the Belize working group of the Declining Amphibian Populations Task Force. For several years, Mayamon volunteers have censused anuran populations using a protocol that estimates numbers of individuals on the basis of male vocalization. To date, the protocol has been evaluated only through a series of post hoc power analyses; I performed the first field test to assess the effect of species-specific mating system characteristics, survey length, survey frequency, and pond selection on census results for anuran communities within a tropical moist forest in Belize. Under the current protocol, I estimate that it would take 359 months of sampling to detect the 11 species I detected at this site using vocalization surveys. In addition, I introduce a method using ANCOVA to determine ideal survey length. Arbitrarily setting the ideal detection to 90% yields a required sampling protocol of 21 minutes; the current minimum of 15 minutes yields only an 80% detection rate. This method could be adapted for use with other monitoring programs, allowing both the assessment of current efficacy and the extrapolation of required sampling length to reach a given efficacy. The results of these approaches indicate that the Mayamon protocol methodology should be extended if it is to allow investigators to adequately understand the community dynamics of amphibians

Evaluation of a Long-Term Amphibian Monitoring Protocol in Central America

The Maya Forest Monitoring Project (Mayamon) was established in 1997 as an outgrowth of the Belize working group of the Declining Amphibian Populations Task Force. For several years, Mayamon volunteers have censused anuran populations using a protocol that estimates numbers of individuals on the basis of male vocalization. To date, the protocol has been evaluated only through a series of post hoc power analyses; I performed the first field test to assess the effect of species-specific mating system characteristics, survey length, survey frequency, and pond selection on census results for anuran communities within a tropical moist forest in Belize. Under the current protocol, I estimate that it would take 359 months of sampling to detect the 11 species I detected at this site using vocalization surveys. In addition, I introduce a method using ANCOVA to determine ideal survey length. Arbitrarily setting the ideal detection to 90% yields a required sampling protocol of 21 minutes; the current minimum of 15 minutes yields only an 80% detection rate. This method could be adapted for use with other monitoring programs, allowing both the assessment of current efficacy and the extrapolation of required sampling length to reach a given efficacy. The results of these approaches indicate that the Mayamon protocol methodology should be extended if it is to allow investigators to adequately understand the community dynamics of amphibians