Ixodes Scapularis In North Dakota: Phenology, Population Genetics, And Local Host Reservoir Competency In An Emerging Vector Population

Tick surveillance in eastern North Dakota has revealed the presence of established I. scapularis populations in fragmented forest habitats previously regarded as unsuitable for this species. Understanding I. scapularis phenology, the reservoir competency of local vertebrate hosts, and population structure of blacklegged ticks in this region is essential to determining potential human risk of Lyme disease. Tick surveys were conducted throughout North Dakota by flagging and small mammal trapping. 1,701 ticks were collected, including 297 I. scapularis exhibiting a relatively low Borrelia burgdorferi infection rate (ca. 3-5%). Seasonal abundance varied greatly among life stages, with adult I. scapularis being most common in the early summer months (May-June) and juvenile I. scapularis abundance increasing later (July-August). Nearly half of all small mammals captured were red-backed voles (Myodes gapperi), and were parasitized by immature blacklegged ticks. To determine whether voles served as reservoirs for Lyme disease F-1 voles were injected with B. burgdorferi s.s. and at 2 and 4 weeks, the voles were infested with larval deer ticks. Engorged ticks were allowed to molt to nymphs and the nymphs were re-fed on naïve laboratory mice to determine if the larval ticks got infected and, as nymphs, were able to transmit the borrelia. Analyses of the mitochondrial DNA of deer ticks collected from North Dakota revealed a high haplotype diversity (Hd=0.80), and genetic structure suggests colonization from multiple sources. Populations fit theoretical models of population expansion using multiple test statistics, indicating potential increase in human tick exposure and Lyme disease incidence

Inhibition of Fructose-1,6-bisphosphatase by Aminoimidazole Carboxamide Ribotide Prevents Growth of Salmonella enterica purH Mutants on Glycerol

The enzyme fructose-1,6-bisphosphatase (FBP) is key regulatory point in gluconeogenesis. Mutants of Salmonella enterica lacking purH accumulate 5-amino-4-imidazole carboxamide ribotide (AICAR) and are unable to utilize glycerol as sole carbon and energy sources. The work described here demonstrates this lack of growth is due to inhibition of FBP by AICAR. Mutant alleles of fbp that restore growth on glycerol encode proteins resistant to inhibition by AICAR and the allosteric regulator AMP. This is the first report of biochemical characterization of substitutions causing AMP resistance in a bacterial FBP. Inhibition of FBP activity by AICAR occurs at physiologically relevant concentrations and may represent a form of regulation of gluconeogenic flux in Salmonella enterica

Thermal Control of an Electronic Enclosure Utilizing a Vapor Chamber

This thesis addresses the problem of extracting heat from sealed electronic enclosures. Typical industry practice is to use various air-to-air and air-to-liquid heat exchangers. These techniques are known to require costly custom designs. This thesis points out how one can apply heat pipe technology in the form of a vapor chamber to solve this type of problem. The details on the design and testing of two prototype vapor chambers are cited. Included in the text are typical industrial applications that require sealed enclosures to protect their associated electronic control hardware. Also mentioned is some historical background on heat pipes

The Utility of Trouble: Maximizing the Value of Our Human Services Dollars

Outlines recommendations to standardize service delivery areas and consolidate area offices of the state's seven largest human services agencies, as well as to close antiquated institutions. Projects benefits such as improved accessibility and savings