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Relating crustal deformation to stress conditions has long been a subject of interest to the geologic community as rock failure has important implications for storage and extraction of petroleum and mineral deposits, as well as sequestration efforts. The ability to relate patterns of rock deformation to stress conditions also permits geologists to better understand structural evolution. This dissertation focuses on interpreting and modeling crustal stress conditions from outcrop to regional scale associated with late Cretaceous to early Eocene deformation across the Colorado Plateau.The first part of this dissertation focuses on salt-related stress perturbations adjacent to the Salt Valley salt wall in the Paradox Basin of southern Utah. Under Late Cretaceous-early Eocene tectonic loading, the salt wall underwent active diapirism via ductile flow because of its inability to sustain differential stress due to inherent mechanical weakness. This phenomenon generated local stress perturbations from regional tectonic conditions in the rock mass adjacent to the deforming salt wall. The first two studies presented in this dissertation improve our ability to interpret and predict stress conditions and the associated rock failure in the perturbed stress environment around salt bodies under tectonic loading. This includes evidence and implications for use of a non-linear failure criterion to describe brittle rock failure, as opposed to the commonly used linear Coulomb failure criterion. The second part of this dissertation focuses on regional tectonic stress and associated Laramide deformation across the Colorado Plateau. Laramide deformation is evidenced by basement-cored uplifts bound by doubly plunging monoclinal folds. Blind basement fault geometries are estimated with trishear fault-propagation models and generalized area-depth calculations. The blind basement fault model is used as inputs into a geomechanical model to evaluate regional Laramide stress conditions respons

Prior laboratory studies suggest that scarcity increases delay discounting (devaluation of delayed outcomes) and disturbs other decision-making processes. Recent evidence on the effect of COVID-19 on delay discounting is mixed. In addition, no study has examined the effect of COVID-19-related scarcity on probability discounting (devaluation of probabilistic outcomes). The present study examined cross-sectional associations between COVID-19-related scarcity, delay discounting, and probability discounting. During April 2020, 1012 participants with low income were recruited on Amazon Mechanical Turk (MTurk) and completed measures of delay and probability discounting of money and food (grocery gift card), COVID-19-related financial impacts, stress, and food security. Regression analyses indicate that compared to those with no COVID-19 related financial impacts, those with severe COVID-19 related financial impacts had greater delay discounting of money and greater delay discounting of food. In addition, greater food insecurity in the past month was associated with greater delay discounting of food but not money. COVID-19 related financial impact was not associated with probability discounting of money or probability discounting of food. Combined with laboratory experiments, the present study provides additional support for the idea that scarcity or income shock may increase delay discounting, particularly during the onset of COVID-19.

Background The Supplemental Nutrition Assistance Program (SNAP) supports Americans with lower income to purchase dietary products at authorized retailers. This research aimed to evaluate SNAP-authorized retailers’ public commitments in support of nutrition security and to examine differences between traditional grocers and nontraditional (e.g., convenience, drug, dollar) SNAP-authorized retailers’ public commitments. Methods Prominent United States (U.S.) SNAP-authorized retailers nationally and in two U.S. states (California and Virginia) were identified based on number of store locations (n = 61). Public information available in grey literature were reviewed and scored using the Business Impact Assessment for Obesity and population-level nutrition (BIA-Obesity) tool. SNAP-authorized retailers were classified as traditional (e.g., grocery) or nontraditional (e.g., non-grocery) retailers. Total BIA-Obesity from 0 to 615, representing low to optimal support) and category scores were calculated for corporate strategy, relationships with external organizations, product formulation, nutrition labeling, product and brand promotion, and product accessibility. Descriptive statistics were used to describe BIA-Obesity scores overall and by category. Mann–Whitney U was used to test for potential differences in median BIA-Obesity total scores between traditional and nontraditional SNAP-authorized retailers (a priori, p < 0.05). Results Average total BIA-Obesity scores for SNAP-authorized retailers ranged from 0 to 112 (16.5 ± 23.3). Total BIA-Obesity scores for traditional SNAP-authorized retailers (32.7 ± 33.6; median 25) were higher than nontraditional SNAP-authorized retailer scores (11.2 ± 16; median 5) (p = 0.008). For BIA-Obesity categories, average scores were highest for the category relationships with external organizations (8.3 ± 10.3) and lowest for promotion practices (0.6 ± 2.1). Conclusions Results of this research underscore a dearth of available evidence and su

The Supplemental Nutrition Assistance Program (SNAP) is one of the largest welfare safety nets in the United States. The purpose of SNAP is to provide low-income eligible families with sufficient funds to reach the cost of a nutritious diet. To mitigate the effects of COVID-19, the maximum SNAP benefits were temporarily increased through September 2021 by a total of 20.3%. On October 1, 2021 the maximum SNAP benefits were permanently increased by 21% from the pre-pandemic levels. A sizeable literature had shown that the pre-pandemic maximum benefit levels were insufficient to reach the full cost of a nutritious diet because individuals spent an insufficient amount of time in food production. This viewpoint considers the question: Are those increases in the maximum SNAP benefits enough to reach the full cost of a nutritious diet when we account for possible changes in home food production labor? In light of the recent pandemic-induced labor market disruptions, this research assesses the needs for additional time inputs to the pre-pandemic food production time amounts given different levels of maximum SNAP benefit adjustments in order to reach the ‘full’ cost of a nutritious diet. We evaluate the feasibility of meeting those additional time needs in the context of reallocating portions of the ‘windfall’ of time normally devoted to working and commuting before the pandemic. Focusing on single headed households we find the temporary 20.3% and the permanent 21% increase both would have to be matched by an increase of about 9 hrs per week in food production in order to reach the full cost of a nutritious diet. This increase seems very unlikely based on historical time allocation patterns. More is needed to be done to increase SNAP benefit adequacy either through further increases to benefit levels and/or through education and outreach efforts designed to improve skills of home meal preparation and time management.

Background The Supplemental Nutrition Assistance Program (SNAP) supports Americans with lower income to purchase dietary products at authorized retailers. This research aimed to evaluate SNAP-authorized retailers’ public commitments in support of nutrition security and to examine differences between traditional grocers and nontraditional (e.g., convenience, drug, dollar) SNAP-authorized retailers’ public commitments. Methods Prominent United States (U.S.) SNAP-authorized retailers nationally and in two U.S. states (California and Virginia) were identified based on number of store locations (n = 61). Public information available in grey literature were reviewed and scored using the Business Impact Assessment for Obesity and population-level nutrition (BIA-Obesity) tool. SNAP-authorized retailers were classified as traditional (e.g., grocery) or nontraditional (e.g., non-grocery) retailers. Total BIA-Obesity from 0 to 615, representing low to optimal support) and category scores were calculated for corporate strategy, relationships with external organizations, product formulation, nutrition labeling, product and brand promotion, and product accessibility. Descriptive statistics were used to describe BIA-Obesity scores overall and by category. Mann–Whitney U was used to test for potential differences in median BIA-Obesity total scores between traditional and nontraditional SNAP-authorized retailers (a priori, p < 0.05). Results Average total BIA-Obesity scores for SNAP-authorized retailers ranged from 0 to 112 (16.5 ± 23.3). Total BIA-Obesity scores for traditional SNAP-authorized retailers (32.7 ± 33.6; median 25) were higher than nontraditional SNAP-authorized retailer scores (11.2 ± 16; median 5) (p = 0.008). For BIA-Obesity categories, average scores were highest for the category relationships with external organizations (8.3 ± 10.3) and lowest for promotion practices (0.6 ± 2.1). Conclusions Results of this research underscore a dearth of available evidence and su

Axially stacked quantum dots (QDs) in nanowires (NWs) have important applications in nanoscale quantum devices and lasers. However, there is lack of study of defect-free growth and structure optimization using the Au-free growth mode. We report a detailed study of self-catalyzed GaAsP NWs containing defect-free axial GaAs QDs (NWQDs). Sharp interfaces (1.8-3.6 nm) allow closely stack QDs with very similar structural properties. High structural quality is maintained when up to 50 GaAs QDs are placed in a single NW. The QDs maintain an emission line width of

Axially stacked quantum dots (QDs) in nanowires (NWs) have important applications in nanoscale quantum devices and lasers. However, there is lack of study of defect-free growth and structure optimization using the Au-free growth mode. We report a detailed study of self-catalyzed GaAsP NWs containing defect-free axial GaAs QDs (NWQDs). Sharp interfaces (1.8-3.6 nm) allow closely stack QDs with very similar structural properties. High structural quality is maintained when up to 50 GaAs QDs are placed in a single NW. The QDs maintain an emission line width of

The Shanxi Rift is a ~1000 km long active rift zone in North China defined by en-echelon NE-SW–trending basins and uplifts. The Taihangshan and Luliangshan (‘shan’ = mountains) constitute the eastern and west-central rift shoulders of the Shanxi Rift. The southern and northern margins of the Shanxi Rift are delimited by the E-SE–striking Qinling fault and the E-trending Yanshan, respectively. The rift zone is thought to have initially formed during the Late Miocene to Pliocene based on the age of alluvial-fluvial-lacustrine and loess deposits that infill the grabens and half-grabens. The age and thickness of these synrift sediments are understood from sparse well control and 2D seismic data, but much of this subsurface data is inaccessible and poorly documented in the international literature; therefore, addressing the timing and magnitude of uplift for the rift-flank uplifts remains challenging. The geology of the footwall blocks is defined by Neoarchean–Paleoproterozoic basements rocks unconformably overlain by Proterozoic metasedimentary rocks and Paleozoic–Mesozoic strata. These rocks are folded and faulted as part of the NE-SW trending Taihang-Luliangshan fold belt, formed during the Middle-Late Jurassic–Early Cretaceous (ca. 160-135 Ma) Yanshanian orogenic event. Shortening at this time is recognized throughout much of North China and was likely a consequence of flat-slab subduction of the Izanagi (i.e., paleo-Pacific) plate under the eastern margin of Asia, although far-field deformation associated with terrane amalgamation in Eurasia may have also played an important role. Shortening transitioned to a phase of extension in North China at ca. 135-130 Ma, which led to the development of high-magnitude extensional core complexes in North China from ca. 130-100 Ma, widespread magmatism, and the formation of Early–Late Cretaceous backarc basins near the trench margin, such as in the East China Sea and Korean Peninsula. This phase of Early–Late Cretaceous extensio

The San Andreas plate boundary zone in southern California is characterized by a broad network of interlacing faults, working within different provinces of activity to accommodate modern Pacific – North America plate boundary motion. These tectonic provinces vary in their fault morphology from transpressional east-west trending faults of the Transverse Ranges, to transtensional northwest trending faults of the southern Mojave in the Eastern California Shear Zone (ECSZ), to the main dextral Southern San Andreas Fault (SSAF) running through the center of it all. Characterizing how strain accumulation translates to earthquake deformation along different areas of a plate boundary fault system is a critical goal for better understanding how faults can work together to accommodate plate boundary motion and for assessing the seismic hazards along individual faults in the system. Achieving this goal, however, requires integrating different perspectives and evidence from all aspects of the active tectonics field, from field-based measurements of paleoseismic offsets and chronologies through tectonic geomorphology and paleoseismic trenching, to modern space-based observations of crustal velocities and strain rates using Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) measurements, to measurements of crustal seismicity and seismic waveform analysis of recent events, to synthesis modeling studies based on crustal dynamics. In this dissertation, I have endeavored to complete an interdisciplinary analysis of fault motion and crustal deformation in southern California, in order to better characterize the current slip rates of faults in and around San Gorgonio Pass and in particular, to deepen our understanding of the possible mechanisms of slip and strain transfer that must exist between the SSAF system and the southern ECSZ system. In this effort, I have sought to quantify the effect of ongoing viscoelastic postseismic displacements on the mod

Background Previous studies have associated elevated mortality risk in central Appalachia with coal-mining activities, but few have explored how different non-coal factors influence the association within each county. Consequently, there is a knowledge gap in identifying effective ways to address health disparities in coal-mining counties. To specifically address this knowledge gap, this study estimated the effect of living in a coal-mining county on non-malignant respiratory diseases (NMRD) mortality, and defined this as “coal-county effect.” We also investigated what factors may accentuate or attenuate the coal-county effect. Methods An ecological epidemiology protocol was designed to observe the characteristics of three populations and to identify the effects of coal-mining on community health. Records for seven coal-mining counties (n = 19,692) were obtained with approvals from the Virginia Department of Health Office of Vital Statistics for the years 2005 to 2012. Also requested were records from three adjacent coal counties (n = 10,425) to provide a geographic comparison. For a baseline comparison, records were requested for eleven tobacco-producing counties (n = 27,800). We analyzed the association of 57,917 individual mortality records in Virginia with coal-mining county residency, county-level socioeconomic status, health access, behavioral risk factors, and coal production. The development of a two-level hierarchical model allowed the coal-county effect to vary by county-level characteristics. Wald tests detected sets of significant factors explaining the variation of impacts across counties. Furthermore, to illustrate how the model estimations help explain health disparities, two coal-mining county case studies were presented. Results The main result revealed that coal-mining county residency increased the probability of dying from NMRD. The coal-county effect was accentuated by surface coal mining, high smoking rates, decreasing health insurance coverage

Background Altering food store environments is a promising approach to encourage healthy product purchases by consumers to improve their diet quality and health. Food store owners and managers are intermediaries to ensure that environmental changes are enacted. Despite their role as gatekeepers to implement and sustain healthy food environment changes, no systematic review has been published that examines food store owner and manager (retailer) data. Thus a review of retailer information available within the expansive United States (US) food environment literature was the purpose of this research. Methods The PRISMA protocol was used. A search strategy, including published articles from years 1980–2017, was applied to six databases to locate relevant articles that addressed the perspective of food store retailers in the US. Data were extracted, organized, and agreed upon between two authors based on pre-designed constructs: (1) a social-ecological model to capture factors that influence retailer decision making; and (2) a marketing-mix and choice-architecture framework to examine perspectives of applied (or the prospective application of) strategies at the store-level. Study quality was assessed using quality criteria checklists for qualitative and quantitative research. Results Thirty-one articles met inclusion criteria and most studies (n = 22) were qualitative and conducted in urban food stores (n = 23). Multiple social-ecological factors influenced retailer decision making and ability or willingness to use marketing-mix and choice-architecture strategies to improve consumers’ healthy choices to support dietary quality. These factors included: conflicting training outcomes to enhance retailers’ knowledge and skills (individual, n = 9); the importance of trust (interpersonal, n = 8); views about marketing-mix and choice-architecture strategies in the food environment (n = 25); consumer demand or demographics (community, n = 19); supplier and food store management

Background Previous studies have associated elevated mortality risk in central Appalachia with coal-mining activities, but few have explored how different non-coal factors influence the association within each county. Consequently, there is a knowledge gap in identifying effective ways to address health disparities in coal-mining counties. To specifically address this knowledge gap, this study estimated the effect of living in a coal-mining county on non-malignant respiratory diseases (NMRD) mortality, and defined this as “coal-county effect.” We also investigated what factors may accentuate or attenuate the coal-county effect. Methods An ecological epidemiology protocol was designed to observe the characteristics of three populations and to identify the effects of coal-mining on community health. Records for seven coal-mining counties (n = 19,692) were obtained with approvals from the Virginia Department of Health Office of Vital Statistics for the years 2005 to 2012. Also requested were records from three adjacent coal counties (n = 10,425) to provide a geographic comparison. For a baseline comparison, records were requested for eleven tobacco-producing counties (n = 27,800). We analyzed the association of 57,917 individual mortality records in Virginia with coal-mining county residency, county-level socioeconomic status, health access, behavioral risk factors, and coal production. The development of a two-level hierarchical model allowed the coal-county effect to vary by county-level characteristics. Wald tests detected sets of significant factors explaining the variation of impacts across counties. Furthermore, to illustrate how the model estimations help explain health disparities, two coal-mining county case studies were presented. Results The main result revealed that coal-mining county residency increased the probability of dying from NMRD. The coal-county effect was accentuated by surface coal mining, high smoking rates, decreasing health insurance coverage

Background Altering food store environments is a promising approach to encourage healthy product purchases by consumers to improve their diet quality and health. Food store owners and managers are intermediaries to ensure that environmental changes are enacted. Despite their role as gatekeepers to implement and sustain healthy food environment changes, no systematic review has been published that examines food store owner and manager (retailer) data. Thus a review of retailer information available within the expansive United States (US) food environment literature was the purpose of this research. Methods The PRISMA protocol was used. A search strategy, including published articles from years 1980–2017, was applied to six databases to locate relevant articles that addressed the perspective of food store retailers in the US. Data were extracted, organized, and agreed upon between two authors based on pre-designed constructs: (1) a social-ecological model to capture factors that influence retailer decision making; and (2) a marketing-mix and choice-architecture framework to examine perspectives of applied (or the prospective application of) strategies at the store-level. Study quality was assessed using quality criteria checklists for qualitative and quantitative research. Results Thirty-one articles met inclusion criteria and most studies (n = 22) were qualitative and conducted in urban food stores (n = 23). Multiple social-ecological factors influenced retailer decision making and ability or willingness to use marketing-mix and choice-architecture strategies to improve consumers’ healthy choices to support dietary quality. These factors included: conflicting training outcomes to enhance retailers’ knowledge and skills (individual, n = 9); the importance of trust (interpersonal, n = 8); views about marketing-mix and choice-architecture strategies in the food environment (n = 25); consumer demand or demographics (community, n = 19); supplier and food store management

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

Robust interpretations of rock thermal histories are critical for resolving the timing and rates of geologic processes, especially as low-temperature thermochronology has become a common tool for investigating the evolution of landscapes and mountain belts and the feedbacks between geodynamic processes. Most interpretations of thermochronologic cooling ages, however, attribute rock cooling entirely to rock exhumation - a common but tenuous assumption in many settings where thermochronology is used to investigate links between tectonics, climate, and landscape evolution, because these places often have history of magmatism. Exploring the complexities - and advantages - of interpreting low-temperature thermochronologic data in magmatic terranes is the principal theme of this work. Using simple analytical approximations as well as the finite-element code Pecube, we characterize the cooling age patterns inside and around plutons emplaced at upper and middle crustal levels and identify the advective and conductive scaling relationships that govern these patterns. We find that the resetting aureole width, the difference between reset and unreset cooling ages in country rocks, and the lag time between pluton crystallization age and pluton cooling age all scale with exhumation rate because this rate sets the advective timescale of cooling. Cooling age-elevation relationships in these steadily exhuming models have changes in slope that would masquerade as changes in exhumation or erosion rates in real datasets, if the thermal effects of the plutons were not accounted for. This is the case both in the country rocks immediately next to upper crustal plutons and, surprisingly, in the country rocks kilometers above mid-crustal plutons with no surface expression. Together with a lag-time analysis useful for the practical question of when it is appropriate to interpret a cooling age as an exhumation rate in crystalline rocks, this work improves our framework for evaluating the eff

This proposal focused on establishing the conditions necessary to induce lymphatic endothelial cell (EC) tube morphogenesis in 3D collagen matrices with the long-term goal of establishing separate networks of lymphatic tubes and co-existing, but not interconnecting networks of blood EC-lined tubes. In addition, we hoped that pericytes, which support blood EC tube networks, but not lymphatic vessel networks, would selectively recruit to one versus the other type of tube. Overall, we made progress, but did not identify the conditions that supported lymphatic tube morphogenesis over the long-term. We did identify some conditions that permitted early survival and some tube formation, but generally this did not persist over the long-term and there were not extensive tube networks observed., Final Summary Darpa grant- DARPA proposal 07-21-Open-BAA-FP-135.

We provide a series of algorithms demonstrating that solutions according to the fundamental game-theoretic solution concept of closed under rational behavior (CURB) sets in two-player, normal-form games can be computed in polynomial time (we also discuss extensions to n-player games). First, we describe an algorithm that identifies all of a player's best responses conditioned on the belief that the other player will play from within a given subset of its strategy space. This algorithm serves as a subroutine in a series of polynomial-time algorithms for finding all minimal CURB sets, one minimal CURB set, and the smallest minimal CURB set in a game. We then show that the complexity of finding a Nash equilibrium can be exponential only in the size of a game's smallest CURB set. Related to this, we show that the smallest CURB set can be an arbitrarily small portion of the game, but it can also be arbitrarily larger than the supports of its only enclosed Nash equilibrium. We test our algorithms empirically and find that most commonly studied academic games tend to have either very large or very small minimal CURB sets.

Schistosomiasis japonica is a major parasitic disease threatening millions of people in China. Though overall prevalence was greatly reduced during the second half of the past century, continued persistence in some areas and cases of re-emergence in others remain major concerns. As many regions in China are approaching disease elimination, obtaining quantitative data on Schistosoma japonicum parasites is increasingly difficult. This study examines the distribution of schistosomiasis in eastern China, taking advantage of the fact that the single intermediate host serves as a major transmission bottleneck. Epidemiological, population-genetic and high-resolution ecological data are combined to construct a predictive model capable of estimating the probability that schistosomiasis occurs in a target area ("spatially explicit schistosomiasis risk"). Results show that intermediate host genetic parameters are correlated with the distribution of endemic disease areas, and that five explanatory variables--altitude, minimum temperature, annual precipitation, genetic distance, and haplotype diversity-discriminate between endemic and non-endemic zones. Model predictions are correlated with human infection rates observed at the county level. Visualization of the model indicates that the highest risks of disease occur in the Dongting and Poyang lake regions, as expected, as well as in some floodplain areas of the Yangtze River. High risk areas are interconnected, suggesting the complex hydrological interplay of Dongting and Poyang lakes with the Yangtze River may be important for maintaining schistosomiasis in eastern China. Results demonstrate the value of genetic parameters for risk modeling, and particularly for reducing model prediction error. The findings have important consequences both for understanding the determinants of the current distribution of S. japonicum infections, and for designing future schistosomiasis surveillance and control strategies. The results also high

The effectiveness of the Expanded Food and Nutrition Education Program in achieving its goals at the national, regional, and state level is unknown. Using US Department of Agriculture (USDA) data from all states and territories for the years 2000–2006, the impact of program and participant characteristics and returns to scale on the three outcome indicators used by the USDA are estimated. Program and participant characteristics do not seem to be as important as the amount of money spent on the program. Generally speaking, there are constant and increasing returns to scale for two of the three federal outcome indices for most states but not all.

The effectiveness of the Expanded Food and Nutrition Education Program in achieving its goals at the national, regional, and state level is unknown. Using US Department of Agriculture (USDA) data from all states and territories for the years 2000–2006, the impact of program and participant characteristics and returns to scale on the three outcome indicators used by the USDA are estimated. Program and participant characteristics do not seem to be as important as the amount of money spent on the program. Generally speaking, there are constant and increasing returns to scale for two of the three federal outcome indices for most states but not all.

Schistosomiasis japonica is a major parasitic disease threatening millions of people in China. Though overall prevalence was greatly reduced during the second half of the past century, continued persistence in some areas and cases of re-emergence in others remain major concerns. As many regions in China are approaching disease elimination, obtaining quantitative data on Schistosoma japonicum parasites is increasingly difficult. This study examines the distribution of schistosomiasis in eastern China, taking advantage of the fact that the single intermediate host serves as a major transmission bottleneck. Epidemiological, population-genetic and high-resolution ecological data are combined to construct a predictive model capable of estimating the probability that schistosomiasis occurs in a target area ("spatially explicit schistosomiasis risk"). Results show that intermediate host genetic parameters are correlated with the distribution of endemic disease areas, and that five explanatory variables--altitude, minimum temperature, annual precipitation, genetic distance, and haplotype diversity-discriminate between endemic and non-endemic zones. Model predictions are correlated with human infection rates observed at the county level. Visualization of the model indicates that the highest risks of disease occur in the Dongting and Poyang lake regions, as expected, as well as in some floodplain areas of the Yangtze River. High risk areas are interconnected, suggesting the complex hydrological interplay of Dongting and Poyang lakes with the Yangtze River may be important for maintaining schistosomiasis in eastern China. Results demonstrate the value of genetic parameters for risk modeling, and particularly for reducing model prediction error. The findings have important consequences both for understanding the determinants of the current distribution of S. japonicum infections, and for designing future schistosomiasis surveillance and control strategies. The results also high

The effectiveness of the Expanded Food and Nutrition Education Program in achieving its goals at the national, regional, and state level is unknown. Using US Department of Agriculture (USDA) data from all states and territories for the years 2000–2006, the impact of program and participant characteristics and returns to scale on the three outcome indicators used by the USDA are estimated. Program and participant characteristics do not seem to be as important as the amount of money spent on the program. Generally speaking, there are constant and increasing returns to scale for two of the three federal outcome indices for most states but not all.

The effectiveness of the Expanded Food and Nutrition Education Program in achieving its goals at the national, regional, and state level is unknown. Using US Department of Agriculture (USDA) data from all states and territories for the years 2000–2006, the impact of program and participant characteristics and returns to scale on the three outcome indicators used by the USDA are estimated. Program and participant characteristics do not seem to be as important as the amount of money spent on the program. Generally speaking, there are constant and increasing returns to scale for two of the three federal outcome indices for most states but not all.

This thesis addresses two challenges in extracting patterns from social data generated by modern sensor systems and electronic mechanisms. First, that such data often combine spatial, temporal, and relational evidence, requiring models that properly utilize the regularities of each domain. Second, that data from open-ended systems often contain a mixture between entities and relationships that are known a priori, others that are explicitly detected, and still others that are latent but significant in interpreting the data. Identifying the final category requires unsupervised inference techniques that can detect certain structures without explicit examples. I present new algorithms designed to address both issues within three frameworks: relational clustering, probabilistic graphical models, and kernel-conditional density estimation. These algorithms are applied to several datasets, including geospatial traces of international shipping traffic and a dynamic network of publicly declared supply relations between US companies. The inference tasks considered include community detection, path prediction, and link prediction. In each case, I present theoretical and empirical results regarding accuracy and complexity, and compare efficacy to previous techniques., Supported in part by ONR under contract N00014-06-1-0104, N00014-08-1-1186, ARL under contract W911NF-08-R-0013, ARI under contract W91WAW-07-C-0063 and ARO under contract W911NF-07-1-0317.

Food intake and obesity related phenotypes are greatly affected by economic factors and yet very little is known about the interaction of economic factors, genetics, behavior, and obesity phenotypes. Recent human population research suggests that a decreasing price of high fat food relative to low fat food has contributed to the current obesity epidemic in humans. The two key elements in this argument are choice and costs. We incorporate these key elements in a closed economy mouse model to study the interactions of economics, genetics, and obesity related phenotypes, using normal mice, and mice with a mutation in the hypothalamus-expressed Tub gene, which has a phenotype of adult onset obesity. Results for both genotypes indicate that as the price of the high fat food falls, consumption of that food increases and consumption of the low fat food declines, but not enough to offset the increase in high fat food so total intake and weight increases, with no statistically-significant differences between genotypes. These results are in contrast to previous literature based on an ad lib, no choice food setting. In addition, in our closed economy model, the Tub mutant showed a numerical and statistically significant increase in body fat percentage and glucose intolerance, whereas these increases were only numerical for the normal mice. Both genotypes showed numerical but statistically insignificant increases in leptin and ghrelin levels. These results show that accounting for choice in neuroeconomic studies is important to understanding the complex regulation of intake, body weight and other related phenotypes.

BACKGROUND Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC), with about 800,000 people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that, long-term, the Three Gorges Dam (TGD) will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes. METHODOLOGY/PRINCIPAL FINDINGS We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages of the three transmission modes below the TGD across four provinces (Hunan, Jiangxi, Hubei and Anhui) to determine whether there was any immediate impact of the TGD on schistosomiasis transmission. Eight sentinel villages were selected to represent both province and transmission mode. The primary end point measured was human incidence. Here we present the results of this five-year longitudinal cohort study. Results showed that the incidence of human S. japonicum infection declined considerably within individual villages and overall mode over the course of the study. This is also reflected in the yearly odds ratios (adjusted) for infection risk that showed significant (P<0.01) downward trends in all modes over the follow-up period. CONCLUSIONS/SIGNIFICANCE The decrease in human S. japonicum incidence observed across all transmission modes in this study can probably be attributed to the annual human and bovine PZQ chemotherapy. If an increase in schistosome transmission had occurred as a result of the TGD, it would be of negligible size compared to the treatment induced decline seen here. It appears therefore that there has been virtually no immediate impact of the TGD on schistosomiasis transmission downstream of the dam.

Food intake and obesity related phenotypes are greatly affected by economic factors and yet very little is known about the interaction of economic factors, genetics, behavior, and obesity phenotypes. Recent human population research suggests that a decreasing price of high fat food relative to low fat food has contributed to the current obesity epidemic in humans. The two key elements in this argument are choice and costs. We incorporate these key elements in a closed economy mouse model to study the interactions of economics, genetics, and obesity related phenotypes, using normal mice, and mice with a mutation in the hypothalamus-expressed Tub gene, which has a phenotype of adult onset obesity. Results for both genotypes indicate that as the price of the high fat food falls, consumption of that food increases and consumption of the low fat food declines, but not enough to offset the increase in high fat food so total intake and weight increases, with no statistically-significant differences between genotypes. These results are in contrast to previous literature based on an ad lib, no choice food setting. In addition, in our closed economy model, the Tub mutant showed a numerical and statistically significant increase in body fat percentage and glucose intolerance, whereas these increases were only numerical for the normal mice. Both genotypes showed numerical but statistically insignificant increases in leptin and ghrelin levels. These results show that accounting for choice in neuroeconomic studies is important to understanding the complex regulation of intake, body weight and other related phenotypes.

In the Basin and Range province of southwestern North America, Oligocene and Miocene normal faults are superimposed upon the Late Cretaceous-early Tertiary magmatic arc. This study examines tilted fault blocks containing dismembered pieces of porphyry systems, including pieces below and peripheral to ore bodies, that are exposed at the modern surface. Features in the magmatic-hydrothermal porphyry systems are used to place constraints on the style of extension in Arizona, and reconstructions of extension are used to examine the deep and peripheral portions of porphyry systems to provide a more complete understanding of porphyry systems as a whole. The Eagle Pass, Tea Cup, and Sheep Mountain porphyry systems of Arizona are examined in this study. In all the study areas, previous interpretations of the style of extension involved strongly listric normal faults. However, similar amounts of tilting observed in hanging wall and footwall rocks, as well as structure contour maps of fault planes, require that down dip curvature on faults was minimal (<1°/km. Instead, extension is shown here to have occurred as sets of nearly planar, "domino-style" normal faults were superimposed upon one another, including in the Pinaleño metamorphic core complex. Reconstructions of Tertiary extension reveal that sodic (-calcic) alteration is occurs 2-4 km peripheral to, and greisen alteration is found structurally below and overlapping with, potassic alteration. In addition, a preliminary reconstruction of extension across the Laramide magmatic arc reveals that the geometry, as revealed by known porphyry systems, is of similar scale to that of other magmatic arcs. These results help further the debate surrounding competing models of continental extension, and combine with previous work to provide a more complete understanding of the geometries of Arizona porphyry systems at the district and arc scale.

BackgroundOncomelania hupensis robertsoni is the sole intermediate host for Schistosoma japonicum in western China. Given the close co-evolutionary relationships between snail host and parasite, there is interest in understanding the distribution of distinct snail phylogroups as well as regional population structures. Therefore, this study focuses on these aspects in a re-emergent schistosomiasis area known to harbour representatives of two phylogroups - the Deyang-Mianyang area in Sichuan Province, China. Based on a combination of mitochondrial and nuclear DNA, the following questions were addressed: 1) the phylogeography of the two O. h. robertsoni phylogroups, 2) regional and local population structure in space and time, and 3) patterns of local dispersal under different isolation-by-distance scenarios.ResultsThe phylogenetic analyses confirmed the existence of two distinct phylogroups within O. h. robertsoni. In the study area, phylogroups appear to be separated by a mountain range. Local specimens belonging to the respective phylogroups form monophyletic clades, indicating a high degree of lineage endemicity. Molecular clock estimations reveal that local lineages are at least 0.69-1.58 million years (My) old and phylogeographical analyses demonstrate that local, watershed and regional effects contribute to population structure. For example, Analyses of Molecular Variances (AMOVAs) show that medium-scale watersheds are well reflected in population structures and Mantel tests indicate isolation-by-distance effects along waterways.ConclusionsThe analyses revealed a deep, complex and hierarchical structure in O. h. robertsoni, likely reflecting a long and diverse evolutionary history. The findings have implications for understanding disease transmission. From a co-evolutionary standpoint, the divergence of the two phylogroups raises species level questions in O. h. robertsoni and also argues for future studies relative to the distinctness of the respective parasite

BackgroundOncomelania hupensis robertsoni is the sole intermediate host for Schistosoma japonicum in western China. Given the close co-evolutionary relationships between snail host and parasite, there is interest in understanding the distribution of distinct snail phylogroups as well as regional population structures. Therefore, this study focuses on these aspects in a re-emergent schistosomiasis area known to harbour representatives of two phylogroups - the Deyang-Mianyang area in Sichuan Province, China. Based on a combination of mitochondrial and nuclear DNA, the following questions were addressed: 1) the phylogeography of the two O. h. robertsoni phylogroups, 2) regional and local population structure in space and time, and 3) patterns of local dispersal under different isolation-by-distance scenarios.ResultsThe phylogenetic analyses confirmed the existence of two distinct phylogroups within O. h. robertsoni. In the study area, phylogroups appear to be separated by a mountain range. Local specimens belonging to the respective phylogroups form monophyletic clades, indicating a high degree of lineage endemicity. Molecular clock estimations reveal that local lineages are at least 0.69-1.58 million years (My) old and phylogeographical analyses demonstrate that local, watershed and regional effects contribute to population structure. For example, Analyses of Molecular Variances (AMOVAs) show that medium-scale watersheds are well reflected in population structures and Mantel tests indicate isolation-by-distance effects along waterways.ConclusionsThe analyses revealed a deep, complex and hierarchical structure in O. h. robertsoni, likely reflecting a long and diverse evolutionary history. The findings have implications for understanding disease transmission. From a co-evolutionary standpoint, the divergence of the two phylogroups raises species level questions in O. h. robertsoni and also argues for future studies relative to the distinctness of the respective parasite

This dissertation is composed of three essays; the first two examine the decisionmaking of potato producing households in Bolivia and the third examines well-being changes among Zimbabwe households. The first essay entitled “The role of risk mitigation in production efficiency: A case study of potato cultivation in the Bolivian Andes” estimates the costs of self-managing environmental risk through activity and environmental diversification. Risk management has the potential to reduce income variability but at the cost of increasing production inefficiency, which we measure employing a stochastic production frontier. Among variables capturing environmental diversification, discontinuity between fields has the most detrimental effect on production efficiency. Activity diversification, measured by the ratio of potato to total crop revenue, has a stronger impact on inefficiency and yield losses than any of the environmental diversification variables. The second essay entitled “Determinants of market participation decisions and marketing choices in Bolivia” examines three decisions related to potato market participation: market entry, volume sold, and market choice. The first two are analyzed using a Heckman selection model. Results indicate that isolation, measured by population density and distance to markets, negatively impacts market entry. The most important determinant of quantity sold is land holding. Market choices are judged according to second-order stochastic dominance (SOSD). Market choices meeting the SOSD criterion are referred to as optimal marketing strategies as they have the higher expected payoff for a minimal income variance. Results suggest that the probability of selecting an optimal marketing strategy increases with quantity sold, access to market information, and access to liquidity while it decreases with distance to markets. The third essay entitled “A profile of changes in well-being in Zimbabwe, 2001- 2007/8, using an asset index methodology”

Urbanization is a global multidimensional process paired with increasing uncertainty due to climate change, migration of people, and changes in the capacity to sustain ecosystem services. This article lays a foundation for discussing transitions in urban governance, which enable cities to navigate change, build capacity to withstand shocks, and use experimentation and innovation in face of uncertainty. Using the three concrete case cities-New Orleans, Cape Town, and Phoenix-the article analyzes thresholds and cross-scale interactions, and expands the scale at which urban resilience has been discussed by integrating the idea from geography that cities form part of "system of cities" (i.e., they cannot be seen as single entities). Based on this, the article argues that urban governance need to harness social networks of urban innovation to sustain ecosystem services, while nurturing discourses that situate the city as part of regional ecosystems. The article broadens the discussion on urban resilience while challenging resilience theory when addressing human-dominated ecosystems. Practical examples of harnessing urban innovation are presented, paired with an agenda for research and policy.

Conservation easements are among the fastest growing techniques for protecting land and open space. Conservation easements are legal agreements between a landowner and a conservation organization that limits or restricts entirely the right to develop a property in order to protect important conservation values associated with the property. At the heart of the conservation easement movement is the assumption that easements will protect ecologically important lands in perpetuity. However, there is little evidence that conservation easements can protect land permanently. Very few land trusts have experience in dealing with the myriad of challenges associated with long-term enforcement of conservation easements. This study sought to examine scenic easements acquired for the Blue Ridge Parkway in the 1930's and 40's and to develop an understanding of the challenges faced by the Parkway in attempting to enforce the terms of scenic easements drafted nearly 70 years ago. The scenic easements acquired for the Blue Ridge Parkways represent the first wide spread use of conservation easements in the country. The Parkway's early architects had few examples of easement programs to assist them in acquiring and managing these early forms of conservation easement nor did the NPS have the network of conservation organizations that exists today. This study reviews the process utilized by the Commonwealth of Virginia and the State of North Carolina to acquire scenic easements for the Blue Ridge Parkway and assesses the deeds used to convey the scenic easements from the states to the federal government. Further, this study evaluates and examines the number and types of violations of easement terms experienced by the Parkway and the various factors that may have contributed to violations of scenic easement restrictions and requests to alter/amend easements. This study also evaluates the various strategies used by the National Park Service to exchange and release scenic easements. Finally

Increasingly, data available to network analysts includes not only relationships between actors but measurements of entity attributes and relations through time and space. Integrating this information with existing dynamic network analysis techniques demands new models and tools. This paper introduces two extensions to the ORA dynamic network analysis platform intended to meet this need. The first, OraGIS, provides geospatial visualization and clustering algorithms. The second, Loom, assists in the analysis of agent movements through a discrete state space "such as a set of named locations" over time. We discuss the capabilities of both tools and their integration with the traditional analytics in the ORA platform., Sponsored in part by Office of Naval Research Dynamic Network Analysis program Grant no. N00014-06-1-0104 and by the National Science Foundation Grant no. DGE-9972762.

Previous work has shown that activities and places of interest can be extracted from GPS traces of human movements using behavioral models based on conditional random fields (CRFs). In this paper, we adapt and extend this work in two ways. First, we apply the framework to analysis of a vehicle-tracking maritime environment, analyzing GPS data from a 5 day surveillance of merchant marine ships conducting exercises in the English channel. Secondly, we expand the model to perform a broader population analysis segmenting the population into several classes with distinct behavioral models. Empirical results show that our algorithm is successful in inferring locations of interest, but makes only coarse distinction in activity inference. In clustering behaviors, it successfully divides agents with highly localized activities from those servicing distant ports., Sponsored in part by National Science Foundation (NSF).

A series of quantitative and structural analyses are applied to geospatial data regarding the movement of Merchant Marine vessels in the English Channel. CASOS has been tasked with developing new computational techniques for analyzing data about Merchant Marine behavior under a Social Network Analysis framework. In this paper we describe an experiment doing so for geospatial data from AIS transponders in 1700+ Merchant Marine vessels during exercise in the English Channel. Our analysis has three phases: Spatial clustering algorithms are used to detect places of interest and relationships between entities the data. Extracted relational information is analyzed in network form. A suite of network analytic measures are applied to find patterns on the network and individual node levels. We apply an intervention analysis which models an intervention (surveying ships at ports) and suggests a strategy for allocating surveillance. The analysis framework is unusual in taking a relational perspective to spatial data, and novel in its principled treatment of the relationship between spatial, two mode, and one mode network representations of data, and in its approach to proposing intervention strategy., Sponsored in part by National Science Foundation (NSF).

Schistosomiasis japonica is a zoonosis of major public health importance in southern China. We undertook a drug intervention to test the hypothesis that buffalo are major reservoirs for human infection in the marshlands/lake areas, where one million people are infected. We compared human and buffalo infection rates and intensity in an intervention village (Jishan), where humans and buffalo were treated with praziquantel, and a control village (Hexi), where only humans were treated, in the Poyang Lake region. Over the four-year study, human incidence in Jishan decreased but increased in Hexi. Adjustment of incidence by age, sex, water exposure, year, and village further confirmed the decreased human infection in Jishan. Chemotherapy for buffaloes resulted in a decrease in buffalo infection rates in Jishan, which coincided with the reduction in human infection rates there in the last two years of the study. Mathematical modeling predicted that buffalo are responsible for 75% of human transmission in Jishan.

Major college recruitment of high school athletes is a very competitive process. There are one hundred and seventeen Division I - A NCAA schools for athletes to choose among. Up to this point, coaches and administrators have speculated what is important to the prospective student-athlete in an attempt to improve certain potential factors like facilities, equipment, coaching changes, etc. The purpose of this study was to determine what factors were important in the decision-making process of prospective student-athletes and discover, as freshman, were they satisfied with their ultimate decision. Eighty-Eight freshmen student-athletes responded to the questionnaire in the months May through July of 2005. The questionnaire was grouped into three main areas of content: Team History, Facilities and Equipment, and Departmental Services. These areas were investigated by means of utilizing a Likert scale and analyzing data by scholarship status, by gender and by team affiliation. The results revealed that the most important factors in one's decision-making process are Education, Coaches, Success of the Program, and Facilities. From these factors, besides Education itself, the main area of focus for a prospective student-athlete is related to Team History, followed by Facilities and Equipment, with Departmental Services being the final area of concern. Also revealed by this study is the fact that there are some differences between the factors a scholarship student-athlete considers and the factors a non-scholarship student-athlete considers in their decision-making process. Finally, this study showed that of those polled, they were satisfied with their decision to participate in collegiate athletics.