Invasive species are capable of causing considerable damage to natural ecosystems, agricultures and economies throughout the world. These invasive species must be identified and adequate control measures should be investigated to prevent and reduce the negative effects associated with exotic species. A recent introduction of an exotic ant, Paratrechina sp. nr. pubens, has caused tremendous economic and ecological damage to southern Texas. Morphometric and phylogenetic procedures were used to identify this pest ant, P. sp. nr. pubens, to Southern Texas. The populations in Texas were found to be slightly different but not discriminating from P. pubens populations described in previous literature. Analysis of the distribution and expansion of P. sp. nr. pubens found numerous geographically discrete populations and moderately expanding territories. These expansion rates were determined to be ~20 and ~30 m per mo for a neighborhood and industrial area, respectively. Several laboratory and field control strategies were implemented for control of this intensely pestiferous species. Dinotefuran exhibited high laboratory efficacy against P. sp. nr. pubens, while treatments using novaluron were inconclusive. The use of expanded-use Termidor� demonstrated trends in these data that suggest it as the treatment of choice. Other field treatments, such as Termidor and Top Choice�, Termidor and Advance Carpenter Ant BaitTM, and Transport� and Talstar� G, did not attain the success found in the expanded-use Termidor treatment. Most treatments examined were determined ineffective against high populations of P. sp. nr. pubens. Additional and more intensive population management regimes should be investigated. Abating further P. sp. nr. pubens population proliferation to other regions will only be realized from additional control research supplemented with state and federal interdiction policies.

Feral swine (Sus scrofa domesticus) are spreading across North America at an alarming rate. Four Canadian provinces and 39 states within the continental United States now report standing populations of feral pigs. Estimates place the number of feral hogs in Texas >2M, accounting for more than half of the United States population. It is known that feral swine impact local ecology following establishment, with regard to shifts in local flora and fauna. The overall objective of this research was to investigate the role of feral swine in tick-borne pathogen transmission in Texas. The underpinning objectives were to establish host records for tick species parasitizing feral swine, determine the species assemblages associated with feral swine among different ecoregions of Texas, determine by immunoassay to which tick-borne bacteria feral pigs were being exposed, and detect the DNA of tick-borne bacteria by polymerase chain reaction assay in the event of poor or early immune response by the host. Feral pigs (N=432) were harvested from June 2008 to June 2010 using box and corral traps and by aerial gunning. Seven species of ticks, Amblyomma americanum, A. cajennense, A. maculatum, Dermacentor albipictus, D. halli, and D. variabilis; and Ixodes scapularis, were collected. Immature stages of A. cajennense and A. americanum were collected as well. All classes of feral pigs, gender by age, were infested with ticks. Serum was collected through a multi-organizational effort from 2006 to 2010 and tested by ELISA for previous exposure to tick-borne pathogens in the genera Rickettsia and Ehrlichia (N=888) and Borrelia (N=849). Prevalence percentages by immunoassay were 27.59 percent, 13.18 percent and 2.12 percent for Rickettsia, Ehrlichia, and Borrelia, respectively. Samples positive by ELISA for exposure to Borrelia were further screened by Western Blot for exposure to Borrelia turicatae. The results were equivocal in most cases. Blood samples (N=233) were collected from 2008 to 2010 and analyzed by polymerase chain reaction for the detection of the DNA of these same three genera of bacteria. Two of the samples were positive by PCR for the presence of Borrelia DNA. Texas feral swine are serving as hosts for at least seven species of ticks and are interacting with tick-borne pathogen transmissions cycles in Texas.

Because software development is increasingly expensive and timeconsuming, software reuse gains importance. Aspect-oriented software development modularizes crosscutting concerns which enables their systematic reuse. Literature provides a number of AOP patterns and best practices for developing reusable aspects based on compelling examples for concerns like tracing, transactions and persistence. However, such best practices are lacking for systematically reusing invasive aspects. In this paper, we present the ‘callback mismatch problem’. This problem arises in the context of abstraction mismatch, in which the aspect is required to issue a callback to the base application. As a consequence, the composition of invasive aspects is cumbersome to implement, difficult to maintain and impossible to reuse. We motivate this problem in a real-world example, show that it persists in the current state-of-the-art, and outline the need for advanced aspectual composition mechanisms to deal with this.

Thesis (M.Sc.)--York University, 2007. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 114-162). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR32029

Reproduction de : Thèse d'exercice : Médecine : Nancy 1 : 2004. / Titre provenant de l'écran-titre.

Thèse d'exercice : Médecine. Pneumologie : Nantes : 2007. / Bibliogr.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 2002. / Title from PDF t.p. (viewed on Dec. 10, 2005). Vita. Includes bibliographical references (p. 70-78).

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Title from first page of PDF file (viewed Febrary 1, 2010). Includes bibliographical references (p. 140-143). Issued in print and online. Available via ProQuest Digital Dissertations.

Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes bibliographical references (p. 119-137).

Introduced species cause both considerable ecological and economic damage every year. However, not much is known about how certain species are able to establish and spread beyond the site of initial introduction, whereas others do not. Species undergoing range expansion following an introduction may prove to be a valuable resource to invasion biology, but may also be informative in light of species' responses to changing environments (i.e. global climate change). Here, I took advantage of an ongoing range expansion of an introduced vertebrate species. House sparrows (Passer domesticus) were introduced to Mombasa, Kenya in the 1950s and have subsequently expanded their range northwest-ward and now occupy most major cities in Kenya. By comparing older, established populations (i.e. those in Mombasa) with more recently colonized populations at the range edge, it might be possible to determine some of the mechanisms that underlie range expansion in some species and/or populations. In Chapter 1, the background and ideas that motivated the rest of the dissertation is summarized. In Chapter 2, I studied how exploration and glucocorticoids (a hormone released in response to stressors) changed throughout the range expansion. Exploration was greater at the range edge, which is likely to ensure greater discovery of novel resources. Glucocorticoids released in response to restraint were also highest at the range edge, which might facilitate resolution of stressors in unpredictable environments. However, chronically elevated levels of glucocorticoids are often considered maladaptive, unless an individual can appropriately cope with them. Therefore, in Chapter 3, I characterized glucocorticoid receptors (i.e. mineralocorticoid receptor (MR) and glucocorticoid receptor (GR)) in the hippocampus, an area responsible for negative feedback of glucocorticoids as well as induction of behavioral and physiological response to stressors. I found that MR density was lower relative to GR density at the range edge compared to the site of introduction (Mombasa). I speculate this pattern is a mechanism to resolve the elevated levels of glucocorticoids at the range edge. Taken together, these results indicate that individuals at the range edge have a strong glucocorticoid response to stressors to induce a rapid, strong response to resolve stressors. Subsequently, in Chapter 4, I examined the potential mechanisms of phenotypic change among Kenyan house sparrows. Typically, following an introduction event, genetic diversity undergoes a bottleneck and is greatly reduced compared to the source population; as such, genetic evolution as the main driver of changing phenotypes throughout the range expansion is unlikely. We therefore hypothesized that epigenetic mechanisms (e.g. DNA methylation) may compensate for the expected reduced genetic diversity following an introduction. Although there was no pattern of epigenetic variation among cities (i.e. variation did not increase nor decrease further from the site of introduction), epigenetic variation increased as genetic inbreeding increased (a sign of reduced genetic diversity and bottlenecks), suggesting epigenetic modifications may compensate for reduced genetic diversity following an introduction event. Overall, patterns of phenotypic variation emerged dependent on age of the population- these patterns may prove to be important in other vertebrate range expansions as well. Surprisingly, epigenetic diversity did not correlate with phenotypic variation among populations; however, within-individual studies may reveal epigenotypes are related to certain behavioral or physiological phenotypes. In the future, studies should be designed to address how phenotypic differences arise despite relatively low genetic diversity and overall high genetic admixture among individuals. In Kenyan house sparrows, maintenance of high levels of flexibility and differential developmental influences may be important factors that lead to varying phenotypes dependent on time since colonization.