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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Spationtemporal population genomics of marine species : invasion, expansion, and connectivity

Bors, Eleanor Kathleen January 2017 (has links)
Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Biology; and the Woods Hole Oceanographic Institution), 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references. / Every genome tells a story. This dissertation contains four such stories, focused on shared themes of marine population dynamics and rapid change, with an emphasis on invasive marine species. Biological invasions are often characterized by a range expansion, during which strong genetic drift is hypothesized to result in decreased genetic diversity with increased distance from the center of the historic range, or the point of invasion. In this dissertation, population genetic and genomic tools are used to approach complex and previously intractable fundamental questions pertaining to the non-equilibrium dynamics of species invasions and rapid range expansions in two invasive marine species: the lionfish, Pterois volitans; and the shrimp, Palaemon macrodactylus. Using thousands of loci sequenced with restriction enzyme associated DNA sequencing in these two systems, this research tests theoretical predictions of the genomic signatures of range expansions. Additionally, the first chapter elucidates patterns of population genetic connectivity for deep-sea invertebrates in the New Zealand region demonstrating intimate relationships between genetics, oceanographic currents, and life history traits. Invasive shrimp results extend our understanding of marine population connectivity to suggest that human-mediated dispersal may be as important - if not more important - than oceanographic and life history considerations in determining genetic connectivity during specific phases of marine invasions. In invasive populations of lionfish, measures of genomic diversity, including a difference between observed and expected heterozygosity, were found to correlate with distance from the point of introduction, even in the absence of spatial metapopulation genetic structure. These results indicate a signal of rapid range expansion. The final study in this dissertation uses an innovative temporal approach to explore observed genomic patterns in the lionfish. In all, this dissertation provides a broad perspective through the study of multiple species undergoing superficially parallel processes that, under more intense scrutiny, are found to be mechanistically unique. It is only through comparative approaches that predictable patterns of population dynamics will emerge. / by Eleanor Kathleen Bors. / Ph. D.
62

Sobrevida e fatores prognósticos em pacientes com adenocarcinoma primário de reto

Mussnich, Heloisa Guedes January 2000 (has links)
O câncer colorretal é a terceira neoplasia mais freqüente no mundo ocidental. No reto encontram-se 30 a 57% dos casos, sendo 80% destes passíveis de alcançar pelo exame digital do reto. Apesar de inúmeros avanços diagnósticos e terapêuticos, ainda são detectados tardiamente. A sobrevida em 5 anos mantém-se em torno de 50%, e os aspectos clínicopatológicos são os critérios prognósticos disponíveis. O presente estudo objetiva avaliar a sobrevida e os fatores clínico-patológicos relacionados aos tumores de reto em nosso meio. Os prontuários de 112 pacientes com adenocarcinoma primário e único de reto submetidos a cirurgia eletiva, num período de 7 anos (1988 a 1995), foram revisados retrospectivamente quanto a: idade, sexo, CEA pré-operatório, tipo e curabilidade da cirurgia, recidiva, seguimento, sobrevida e histopatologia do tumor. Para análise da sobrevida utilizou-se o método de Kaplan-Meyer. Nas análises bivariada e estratificada, um valor de P <0,05 foi considerado significativo. O coeficiente de correlação de Kendall foi utilizado para comparação dos sistemas de estadiamento. No modelo multivariado, utilizou-se um IC de 90%. A média de idade foi de 62,03±14,37 anos, com 52% dos casos do sexo feminino.Sessenta e dois por cento dos tumores encontravam-se no reto distal. Foram submetidos a amputação do reto 56,3% dos casos, e os demais, a retossigmoidectomia, sendo 25 procedimentos não-curativos. Sessenta e quatro pacientes (57%) apresentaram recidiva tumoral (14,3% locorregional, 32,1% à distância, e 10,7% ambas). Quarenta e cinco pacientes (40%) faleceram da neoplasia. O tempo mediano de seguimento foi de 35,27 meses (14,5 – 57,63). A sobrevida em 5 anos foi de 51%, tendo reduzido proporcionalmente ao avanço dos estágios histopatológicos da doença (P<0,001). O sistema de estadiamento de Dukes/Astler- Coller se correlacionou significativamente com o sistema TNM (τ=0,91). O adenocarcinoma 6 moderadamente diferenciado foi o mais freqüente (73,2%). A maioria dos tumores (68,2%) estendia-se até os tecidos perirretais; apenas 3,8% eram restritos à mucosa. Sessenta e sete pacientes tinham linfonodos positivos (29,4%, N1; e 30,3%, N2). Na classificação de Dukes/Astler-Coller, 14 eram estágio D; 55, C1 e C2; 15, B2; e 28, B1 e A. A localização do tumor no reto médio ou distal não influenciou a ocorrência dos óbitos, as recidivas, nem a curabilidade da cirurgia. Os tumores menos diferenciados (P=0,009), com maior penetração na parede (P=0,013), com envolvimento linfonodal (N2>N1, P<0,001), com cirurgia nãocurativa (P=0,002) e os que apresentaram recidiva (P<0,001) influenciaram significativamente a mortalidade. A classificação de Dukes/Astler-Coller e a diferenciação tumoral (P=0,089) foram fatores prognósticos independentes, bem como a penetração do tumor na parede retal (P=0,091) e o comprometimento linfonodal (P<0,001), quando excluída a classificação histopatológica. Os achados deste estudo estão de acordo com a literatura. Além da diferenciação tumoral, os fatores prognósticos identificados correspondem aos níveis de classificação dos sistemas de estadiamento vigentes, concordando com a observação de que estes ainda são os critérios prognósticos disponíveis. Este relato corrobora a predominância dos tumores em estágios avançados ao diagnóstico e a ausência de valor prognóstico da localização do tumor no reto. / Colorectal cancer is the third most common neoplasia in the Western world. About 30 to 57% of cases occur in the rectum, and, among these, 80% can be reached by digital rectal examination. However, most of them are diagnosed in advanced stages. Five-year survival rate is maintained at about 50% and clinicopathological features are still the prognostic criteria available. To evaluate survival and clinicopathological factors, the records of 112 patients submitted to elective resection of adenocarcinoma of the rectum from 1988 to 1995 were reviewed. Data were analysed as for: age, gender, preoperative serum level of CEA, type and curability of surgery, recurrence, follow-up, survival and tumor histopathology. Kaplan- Meyer method was used to analyse survival. Statistical significance on bivariate and stratified analysis was considered for a P value less than 0,05. Kendall correlation coefficient was used to compare histopathologic classifications. In the multivariate model, a 90% confidence interval was considered significant. Mean (SD) age was 62 (14) years and 52% of patients were female. Sixty-two percent of rectal tumors were distally located. Abdominoperineal resection was performed in 56% of cases and the remaining patients underwent low anterior resection. Twenty-five (22%) of these were non-curative procedures.Overall, recurrence was observed in 64 (57%) patients: local in 14%, distant in 32% and both in 10%. Forty-five patients (40%) died from disease. Median (range) follow-up was 35 (14 - 57) months. Fiveyear survival rate was 51% and reduced significantly by tumor progression (histopathologic stages; P<0,001). Both stage systems were well correlated (τ=0,91). Moderately differentiated adenocarcinoma was the most frequent tumor grade (73%). Most tumors (68%) extended to perirectal tissues, only 4% were confined to the mucosa. Positive lymph nodes were observed in 67 patients (30% each, N1 and N2). Fourteen patients were Dukes/Astler-Coller D stage; 55 were C1 or C2; 15 were B2; and 28 were B1 or A. Tumor location had no influence on deaths, recurrences or curability. On bivariate analysis, tumor grade (P=0,009), depth (P=0,013) or recurrence (P<0,001), lymph node involvement (N2>N1, P<0,001), noncurative procedure (P=0,002) related with poorer outcome. On multivariate analyses, Dukes/Astler-Coller stages and tumor grade (P=0,089) were found to be independent prognostic factors, as well as depth of invasion and lymph node involvement, when excluding Dukes staging (P=0,091 and <0,001, respectively). These findings are similar to those reported in the literature. Besides tumor grade, prognostic factors identified meet classification levels on current staging systems. Accordingly, these criteria are still the prognostic factors available. The present report corroborates the predominance of advanced stage tumours at diagnosis and the lack of prognostic value of tumor location in the rectum.
63

Sobrevida e fatores prognósticos em pacientes com adenocarcinoma primário de reto

Mussnich, Heloisa Guedes January 2000 (has links)
O câncer colorretal é a terceira neoplasia mais freqüente no mundo ocidental. No reto encontram-se 30 a 57% dos casos, sendo 80% destes passíveis de alcançar pelo exame digital do reto. Apesar de inúmeros avanços diagnósticos e terapêuticos, ainda são detectados tardiamente. A sobrevida em 5 anos mantém-se em torno de 50%, e os aspectos clínicopatológicos são os critérios prognósticos disponíveis. O presente estudo objetiva avaliar a sobrevida e os fatores clínico-patológicos relacionados aos tumores de reto em nosso meio. Os prontuários de 112 pacientes com adenocarcinoma primário e único de reto submetidos a cirurgia eletiva, num período de 7 anos (1988 a 1995), foram revisados retrospectivamente quanto a: idade, sexo, CEA pré-operatório, tipo e curabilidade da cirurgia, recidiva, seguimento, sobrevida e histopatologia do tumor. Para análise da sobrevida utilizou-se o método de Kaplan-Meyer. Nas análises bivariada e estratificada, um valor de P <0,05 foi considerado significativo. O coeficiente de correlação de Kendall foi utilizado para comparação dos sistemas de estadiamento. No modelo multivariado, utilizou-se um IC de 90%. A média de idade foi de 62,03±14,37 anos, com 52% dos casos do sexo feminino.Sessenta e dois por cento dos tumores encontravam-se no reto distal. Foram submetidos a amputação do reto 56,3% dos casos, e os demais, a retossigmoidectomia, sendo 25 procedimentos não-curativos. Sessenta e quatro pacientes (57%) apresentaram recidiva tumoral (14,3% locorregional, 32,1% à distância, e 10,7% ambas). Quarenta e cinco pacientes (40%) faleceram da neoplasia. O tempo mediano de seguimento foi de 35,27 meses (14,5 – 57,63). A sobrevida em 5 anos foi de 51%, tendo reduzido proporcionalmente ao avanço dos estágios histopatológicos da doença (P<0,001). O sistema de estadiamento de Dukes/Astler- Coller se correlacionou significativamente com o sistema TNM (τ=0,91). O adenocarcinoma 6 moderadamente diferenciado foi o mais freqüente (73,2%). A maioria dos tumores (68,2%) estendia-se até os tecidos perirretais; apenas 3,8% eram restritos à mucosa. Sessenta e sete pacientes tinham linfonodos positivos (29,4%, N1; e 30,3%, N2). Na classificação de Dukes/Astler-Coller, 14 eram estágio D; 55, C1 e C2; 15, B2; e 28, B1 e A. A localização do tumor no reto médio ou distal não influenciou a ocorrência dos óbitos, as recidivas, nem a curabilidade da cirurgia. Os tumores menos diferenciados (P=0,009), com maior penetração na parede (P=0,013), com envolvimento linfonodal (N2>N1, P<0,001), com cirurgia nãocurativa (P=0,002) e os que apresentaram recidiva (P<0,001) influenciaram significativamente a mortalidade. A classificação de Dukes/Astler-Coller e a diferenciação tumoral (P=0,089) foram fatores prognósticos independentes, bem como a penetração do tumor na parede retal (P=0,091) e o comprometimento linfonodal (P<0,001), quando excluída a classificação histopatológica. Os achados deste estudo estão de acordo com a literatura. Além da diferenciação tumoral, os fatores prognósticos identificados correspondem aos níveis de classificação dos sistemas de estadiamento vigentes, concordando com a observação de que estes ainda são os critérios prognósticos disponíveis. Este relato corrobora a predominância dos tumores em estágios avançados ao diagnóstico e a ausência de valor prognóstico da localização do tumor no reto. / Colorectal cancer is the third most common neoplasia in the Western world. About 30 to 57% of cases occur in the rectum, and, among these, 80% can be reached by digital rectal examination. However, most of them are diagnosed in advanced stages. Five-year survival rate is maintained at about 50% and clinicopathological features are still the prognostic criteria available. To evaluate survival and clinicopathological factors, the records of 112 patients submitted to elective resection of adenocarcinoma of the rectum from 1988 to 1995 were reviewed. Data were analysed as for: age, gender, preoperative serum level of CEA, type and curability of surgery, recurrence, follow-up, survival and tumor histopathology. Kaplan- Meyer method was used to analyse survival. Statistical significance on bivariate and stratified analysis was considered for a P value less than 0,05. Kendall correlation coefficient was used to compare histopathologic classifications. In the multivariate model, a 90% confidence interval was considered significant. Mean (SD) age was 62 (14) years and 52% of patients were female. Sixty-two percent of rectal tumors were distally located. Abdominoperineal resection was performed in 56% of cases and the remaining patients underwent low anterior resection. Twenty-five (22%) of these were non-curative procedures.Overall, recurrence was observed in 64 (57%) patients: local in 14%, distant in 32% and both in 10%. Forty-five patients (40%) died from disease. Median (range) follow-up was 35 (14 - 57) months. Fiveyear survival rate was 51% and reduced significantly by tumor progression (histopathologic stages; P<0,001). Both stage systems were well correlated (τ=0,91). Moderately differentiated adenocarcinoma was the most frequent tumor grade (73%). Most tumors (68%) extended to perirectal tissues, only 4% were confined to the mucosa. Positive lymph nodes were observed in 67 patients (30% each, N1 and N2). Fourteen patients were Dukes/Astler-Coller D stage; 55 were C1 or C2; 15 were B2; and 28 were B1 or A. Tumor location had no influence on deaths, recurrences or curability. On bivariate analysis, tumor grade (P=0,009), depth (P=0,013) or recurrence (P<0,001), lymph node involvement (N2>N1, P<0,001), noncurative procedure (P=0,002) related with poorer outcome. On multivariate analyses, Dukes/Astler-Coller stages and tumor grade (P=0,089) were found to be independent prognostic factors, as well as depth of invasion and lymph node involvement, when excluding Dukes staging (P=0,091 and <0,001, respectively). These findings are similar to those reported in the literature. Besides tumor grade, prognostic factors identified meet classification levels on current staging systems. Accordingly, these criteria are still the prognostic factors available. The present report corroborates the predominance of advanced stage tumours at diagnosis and the lack of prognostic value of tumor location in the rectum.
64

Sobrevida e fatores prognósticos em pacientes com adenocarcinoma primário de reto

Mussnich, Heloisa Guedes January 2000 (has links)
O câncer colorretal é a terceira neoplasia mais freqüente no mundo ocidental. No reto encontram-se 30 a 57% dos casos, sendo 80% destes passíveis de alcançar pelo exame digital do reto. Apesar de inúmeros avanços diagnósticos e terapêuticos, ainda são detectados tardiamente. A sobrevida em 5 anos mantém-se em torno de 50%, e os aspectos clínicopatológicos são os critérios prognósticos disponíveis. O presente estudo objetiva avaliar a sobrevida e os fatores clínico-patológicos relacionados aos tumores de reto em nosso meio. Os prontuários de 112 pacientes com adenocarcinoma primário e único de reto submetidos a cirurgia eletiva, num período de 7 anos (1988 a 1995), foram revisados retrospectivamente quanto a: idade, sexo, CEA pré-operatório, tipo e curabilidade da cirurgia, recidiva, seguimento, sobrevida e histopatologia do tumor. Para análise da sobrevida utilizou-se o método de Kaplan-Meyer. Nas análises bivariada e estratificada, um valor de P <0,05 foi considerado significativo. O coeficiente de correlação de Kendall foi utilizado para comparação dos sistemas de estadiamento. No modelo multivariado, utilizou-se um IC de 90%. A média de idade foi de 62,03±14,37 anos, com 52% dos casos do sexo feminino.Sessenta e dois por cento dos tumores encontravam-se no reto distal. Foram submetidos a amputação do reto 56,3% dos casos, e os demais, a retossigmoidectomia, sendo 25 procedimentos não-curativos. Sessenta e quatro pacientes (57%) apresentaram recidiva tumoral (14,3% locorregional, 32,1% à distância, e 10,7% ambas). Quarenta e cinco pacientes (40%) faleceram da neoplasia. O tempo mediano de seguimento foi de 35,27 meses (14,5 – 57,63). A sobrevida em 5 anos foi de 51%, tendo reduzido proporcionalmente ao avanço dos estágios histopatológicos da doença (P<0,001). O sistema de estadiamento de Dukes/Astler- Coller se correlacionou significativamente com o sistema TNM (τ=0,91). O adenocarcinoma 6 moderadamente diferenciado foi o mais freqüente (73,2%). A maioria dos tumores (68,2%) estendia-se até os tecidos perirretais; apenas 3,8% eram restritos à mucosa. Sessenta e sete pacientes tinham linfonodos positivos (29,4%, N1; e 30,3%, N2). Na classificação de Dukes/Astler-Coller, 14 eram estágio D; 55, C1 e C2; 15, B2; e 28, B1 e A. A localização do tumor no reto médio ou distal não influenciou a ocorrência dos óbitos, as recidivas, nem a curabilidade da cirurgia. Os tumores menos diferenciados (P=0,009), com maior penetração na parede (P=0,013), com envolvimento linfonodal (N2>N1, P<0,001), com cirurgia nãocurativa (P=0,002) e os que apresentaram recidiva (P<0,001) influenciaram significativamente a mortalidade. A classificação de Dukes/Astler-Coller e a diferenciação tumoral (P=0,089) foram fatores prognósticos independentes, bem como a penetração do tumor na parede retal (P=0,091) e o comprometimento linfonodal (P<0,001), quando excluída a classificação histopatológica. Os achados deste estudo estão de acordo com a literatura. Além da diferenciação tumoral, os fatores prognósticos identificados correspondem aos níveis de classificação dos sistemas de estadiamento vigentes, concordando com a observação de que estes ainda são os critérios prognósticos disponíveis. Este relato corrobora a predominância dos tumores em estágios avançados ao diagnóstico e a ausência de valor prognóstico da localização do tumor no reto. / Colorectal cancer is the third most common neoplasia in the Western world. About 30 to 57% of cases occur in the rectum, and, among these, 80% can be reached by digital rectal examination. However, most of them are diagnosed in advanced stages. Five-year survival rate is maintained at about 50% and clinicopathological features are still the prognostic criteria available. To evaluate survival and clinicopathological factors, the records of 112 patients submitted to elective resection of adenocarcinoma of the rectum from 1988 to 1995 were reviewed. Data were analysed as for: age, gender, preoperative serum level of CEA, type and curability of surgery, recurrence, follow-up, survival and tumor histopathology. Kaplan- Meyer method was used to analyse survival. Statistical significance on bivariate and stratified analysis was considered for a P value less than 0,05. Kendall correlation coefficient was used to compare histopathologic classifications. In the multivariate model, a 90% confidence interval was considered significant. Mean (SD) age was 62 (14) years and 52% of patients were female. Sixty-two percent of rectal tumors were distally located. Abdominoperineal resection was performed in 56% of cases and the remaining patients underwent low anterior resection. Twenty-five (22%) of these were non-curative procedures.Overall, recurrence was observed in 64 (57%) patients: local in 14%, distant in 32% and both in 10%. Forty-five patients (40%) died from disease. Median (range) follow-up was 35 (14 - 57) months. Fiveyear survival rate was 51% and reduced significantly by tumor progression (histopathologic stages; P<0,001). Both stage systems were well correlated (τ=0,91). Moderately differentiated adenocarcinoma was the most frequent tumor grade (73%). Most tumors (68%) extended to perirectal tissues, only 4% were confined to the mucosa. Positive lymph nodes were observed in 67 patients (30% each, N1 and N2). Fourteen patients were Dukes/Astler-Coller D stage; 55 were C1 or C2; 15 were B2; and 28 were B1 or A. Tumor location had no influence on deaths, recurrences or curability. On bivariate analysis, tumor grade (P=0,009), depth (P=0,013) or recurrence (P<0,001), lymph node involvement (N2>N1, P<0,001), noncurative procedure (P=0,002) related with poorer outcome. On multivariate analyses, Dukes/Astler-Coller stages and tumor grade (P=0,089) were found to be independent prognostic factors, as well as depth of invasion and lymph node involvement, when excluding Dukes staging (P=0,091 and <0,001, respectively). These findings are similar to those reported in the literature. Besides tumor grade, prognostic factors identified meet classification levels on current staging systems. Accordingly, these criteria are still the prognostic factors available. The present report corroborates the predominance of advanced stage tumours at diagnosis and the lack of prognostic value of tumor location in the rectum.
65

Spatial Analysis of the Invasion of Red Lionfish, Pterois volitans/miles, in the Western Atlantic Ocean and Caribbean Sea

Johnston, Matthew W. 09 December 2010 (has links)
Pterois volitans and Pterois miles, two species of lionfish from the South Pacific and Indian Ocean, have become prolific invaders of reef, hard bottom, mangrove, and sea grass habitats along the United States Atlantic coast and Caribbean. Their route and timing of introduction is poorly understood. However, historical sightings and captures have been robustly documented since their introduction. This study presents an in-depth analysis of these records based on spatial location, dates of arrival, and physical factors present at capture sights. A stage map was created showing the progression of the invasion as a series of current-driven and proximity-based recruitment periods based on the observed invasion pattern. Using a model that was developed for this study, the relationship between depth, salinity, temperature, and current was examined, finding the latter to be the most influential parameter for transport to new areas. Temperature and extreme depth are perceived as the only limiting factors in the invasion. This predictive model can be applied to other species and locations.
66

Exploring the Relationship between Strategic Thinking and Absorptive Capacity: A Proposed Typology

Srivastava, Saurabh 12 1900 (has links)
Absorptive capacity plays an important role in the organizational adaptation process. Prior research on absorptive capacity focuses on its role in organizational outcomes such as financial performance, innovation, new product development, etc. Recently, scholars have called for research on factors that influence absorptive capacity. Because absorptive capacity plays a vital role in achieving organizational outcomes, it behooves us to improve our understanding of absorptive capacity and its antecedents to serve both researchers and practitioners. In this investigation, strategic thinking is posited to be a key antecedent of absorptive capacity. Capability theory suggests that strategic thinking is a metaphysical (higher order) capability that influences an organization's absorptive capacity. Combining this argument with Miles and Snow's typology of organizational adaptation process, it is posited that the relationship between strategic thinking and absorptive capacity can be clustered into different "groups." Prospectors, defenders, and analyzers, characterized in Miles and Snow's typology of firms are viewed as distinctive groups that exhibit different relationships between strategic thinking and absorptive capacity. Results from an empirical examination suggest that strategic thinking is positively related to absorptive capacity. The results also suggest that the relationship between these two constructs is different between these groups and that the strategic thinking of prospectors has a weaker relationship with absorptive capacity than other type of firms.
67

Florida's Workers Compensation Law: The Pendulum Swings

Hirsch, Ursula 01 January 2017 (has links)
The intent of this paper is to discuss how the recent court rulings on the current workers compensation statutes will impact the rules to Florida’s workers compensation laws. Workers Compensation system is a social justice system that protects both the employer and employee. Employees that are injured while in the course and scope of their employment give up the right to sue, making workers compensation an exclusive remedy. In exchange for giving up that right, the injured worker receives statutory benefits in a no-fault system. This paper covers the legislative changes over the years that have impacted the constitutionality of the system and discusses how these changes have failed to uphold the legislative intent and design of the entire system. It covers the decisions rendered by the Florida Supreme Court and discusses the implications of those decisions.
68

Vehicle Fuel Economy And Vehicle Miles Traveled: An Empirical Investigation Of Jevons’ Paradox

Munyon, Vinola Vincent 14 November 2014 (has links)
No description available.
69

Towards a Neighborhood-Scale Carbon Calculator

McKinley, Samuel Andrew 10 August 2009 (has links)
No description available.
70

VIRGINIA TRANSPORTATION FUNDING: AN ANALYSIS OF ENHANCING THE SECONDARY HIGHWAY SYSTEM CONSTRUCTION ALLOCATION MODEL USING BRIAN D. TAYLOR’S GEOGRAPHICAL EQUITY CRITERIA

Point, Wendell 08 November 2012 (has links)
The focus of this research is Virginia’s Secondary Highway Construction System funding allocations and its impact on statewide deficient lane miles reduction. The research question guiding this study is: “Which of the four allocation models -- the current Secondary Highway System allocation model or one of three alternatives of this model based on Brian D. Taylor’s geographic equity categories (outcome, opportunity, and market) best maximizes statewide deficient lane miles reductions?” Taylor defines each of these geographic equity categories (independent variables for this study) for all levels of government. While Taylor’s research focus has been on equity as it relates to transit and congestion pricing, this study applied his construct to highways. As a result of scanning subjects related to transportation, the need for this study became apparent. Since the 1980’s, Virginia’s highway allocation formula has not changed (Virginia Department of Transportation, 2005). The Virginia General Assembly has sponsored follow-up studies through a series of resolutions over the years (Auditor of Pubic Accounts, 2004). To date, none of the legislatively sponsored research findings have prompted an update of Virginia’s highway allocation formula (Virginia Transportation Research Council, 2008). There is a significant academic and professional literature on federal transportation politics and specific transportation engineering issues. However, there is very limited research on the development of state level highway transportation funding methodologies. This study used the quantitative research approach, which is concerned with determining the relationship between one factor (an independent variable) and another (a dependent or outcome variable) in a population (Walker, 2005, Newman, 1998, and Geddes, 1990). Therefore, this study employed the quantitative research approach to study cause and effect (Mulhall, 2004, Loughborough, 1995, and Collier 1995) relationships of Virginia’s Secondary construction allocations to individual counties and statewide deficient lane miles reductions overall. The .20 portion of the formula for area was examined because this data rarely changes due to locality annexations. Conversely, the .80 portion of the formula was excluded from the analysis because of the demographic variability due to population shifts. As such, the Federal Highway Administration and states update population statistics from the decennial census with the apportionment of funds for formula based programs such as Virginia’s Secondary Highway Construction program (Federal Register, 2002). This researcher concluded that of the four geographic allocation models, the geographic opportunity equity maximized an additional 4.15 statewide deficient lane miles reductions over the baseline model. This study recommends using the geographic opportunity equity model when allocating Virginia’s Secondary Highway Construction funds to maximize the statewide deficient lane miles reductions above the baseline model, the geographic market equity model and the geographic outcome equity model.

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