Modeling the Influence of Environment and Intervention on Cholera in Haiti

We propose a simple model with two infective classes in order to model the cholera epidemic in Haiti. We include the impact of environmental events (rainfall, temperature and tidal range) on the epidemic in the Artibonite and Ouest regions by introducing terms in the transmission rate that vary with environmental conditions. We fit the model on weekly data from the beginning of the epidemic until December 2013, including the vaccination programs that were recently undertaken in the Ouest and Artibonite regions. We then modified these projections excluding vaccination to assess the programs' effectiveness. Using real-time daily rainfall, we found lag times between precipitation events and new cases that range from 3.4 to 8.4 weeks in Artibonite and 5.1 to 7.4 in Ouest. In addition, it appears that, in the Ouest region, tidal influences play a significant role in the dynamics of the disease. Intervention efforts of all types have reduced case numbers in both regions; however, persistent outbreaks continue. In Ouest, where the population at risk seems particularly besieged and the overall population is larger, vaccination efforts seem to be taking hold more slowly than in Artibonite, where a smaller core population was vaccinated. The models including the vaccination programs predicted that a year and six months later, the mean number of cases in Artibonite would be reduced by about two thousand cases, and in Ouest by twenty four hundred cases below that predicted by the models without vaccination. We also found that vaccination is best when done in the early spring, and as early as possible in the epidemic. Comparing vaccination between the first spring and the second, there is a drop of about 40% in the case reduction due to the vaccine and about 10% per year after that

Relational Trust within an Urban Public Comprehensive High School District in Northern California

The 2013 adoption of the Local Control Funding Formula and Local Control Accountability Plan provides local communities and districts with educational decision-making and provides a roadmap of how to improve outcomes in low-performing districts. One of the eight-priority areas California public school districts are held accountable to make progress on an annual basis is improving school climate. Building strong trust based relationships prepares schools to address a myriad of complex challenges. This dissertation examined the key facets that build relational trust between high school teachers and principals within a hierarchical role relationship in a public comprehensive high school district in Northern California. This mixed methods study stretched previous research to understand how secondary principals and teachers conceptualize relational trust. Survey and one-on-one interview data suggest gender, ethnicity, and years of experience are not significantly related to the conceptualization of relational trust and that high school teachers largely feel the same way, regardless of gender, ethnicity, or years of experience. Of note, principals and high school teachers may view the importance of the five facets of relational trust in a dissimilar manner. Principals are encouraged to understand that 10 out of 11 high school teacher groups, while also recognizing that past experiences have a profound influence on the trust building process, ranked reliability as the most important facet in the trust building process

Reduction of voluntary dehydration during effort in hot environments

During an experimental marching trip the daily positive fluid balance was preserved by providing a wide choice of beverages during the hours of the day. It was found that the beverage most suitable for drinking in large quantities during periods of effort was a cold drink with sweetened (citrus) fruit taste. Carbonated drinks, including beer, but milk also, were found unsuitable for this purpose