Introducing Preference Heterogeneity into a Monocentric Urban Model: an Agent-Based Land Market Model

This paper presents an agent-based urban land market model. We first replace the centralized price determination mechanism of the monocentric urban market model with a series of bilateral trades distributed in space and time. We then run the model for agents with heterogeneous preferences for location. Model output is analyzed using a series of macro-scale economic and landscape pattern measures, including land rent gradients estimated using simple regression. We demonstrate that heterogeneity in preference for proximity alone is sufficient to generate urban expansion and that information on agent heterogeneity is needed to fully explain land rent variation over space. Our agent-based land market model serves as computational laboratory that may improve our understanding of the processes generating patterns observed in real-world data

The Implications of Skewed Risk Perception for a Dutch Coastal Land Market: Insights from an Agent-Based Computational Economics Model

Dutch coastal land markets are characterized by high amenity values but are threatened by potential coastal hazards, leading to high potential damage costs from flooding. Yet, Dutch residents generally perceive low or no flood risk. Using an agent-based land market model and Dutch survey data on risk perceptions and location preferences, this paper explores the patterns of land development and land rents produced by buyers with low, highly skewed risk perceptions. We find that, compared to representative agent and uniform risk perception models, the skewed risk perception distribution produces substantially more, high-valued development in risky coastal zones, potentially creating economically significant risks triggered by the current Dutch flood protection polic

HIV/AIDS-associated beliefs and practices relating to diet and work in southeastern Uganda

To explore beliefs relating to diet, work, and HIV/AIDS among the Busoga of rural southeastern Uganda, a cross-sectional survey of 322 adults was conducted in 2007 in Mayuge district, Uganda. Of these adults, 56 were HIV-infected, 120 had a family member with HIV/AIDS, and 146 were in households without HIV-infected members. More than 74.2% of the adults knew someone with HIV/AIDS, and more than 90% correctly identified transmission modes and prevention methods of HIV. In total, 93.2% believed that a person with HIV should work fewer hours to conserve energy but all the three participant groups reported the same working hours. Also, 91.6% believed that a person with HIV infection should eat special nutritious foods, and the participants with HIV infection reported eating more fruits (p=0.020) and vegetables (p=0.012) than other participants. The participants expressed a consistent set of health beliefs about practices relating to HIV/AIDS

HIV/AIDS-associated beliefs and practices relating to diet and work in southeastern Uganda

To explore beliefs relating to diet, work, and HIV/AIDS among the Busoga of rural southeastern Uganda, a cross-sectional survey of 322 adults was conducted in 2007 in Mayuge district, Uganda. Of these adults, 56 were HIV-infected, 120 had a family member with HIV/AIDS, and 146 were in households without HIVinfected members. More than 74.2% of the adults knew someone with HIV/AIDS, and more than 90% correctly identified transmission modes and prevention methods of HIV. In total, 93.2% believed that a person with HIV should work fewer hours to conserve energy but all the three participant groups reported the same working hours. Also, 91.6% believed that a person with HIV infection should eat special nutritious foods, and the participants with HIV infection reported eating more fruits (p=0.020) and vegetables (p=0.012) than other participants. The participants expressed a consistent set of health beliefs about practices relating to HIV/AIDS

Land system science and sustainable development of the earth system: A global land project perspective

Land systems are the result of human interactions with the natural environment. Understanding the drivers, state, trends and impacts of different land systems on social and natural processes helps to reveal how changes in the land system affect the functioning of the socio-ecological system as a whole and the tradeoff these changes may represent. The Global Land Project has led advances by synthesizing land systems research across different scales and providing concepts to further understand the feedbacks between social-and environmental systems, between urban and rural environments and between distant world regions. Land system science has moved from a focus on observation of change and understanding the drivers of these changes to a focus on using this understanding to design sustainable transformations through stakeholder engagement and through the concept of land governance. As land use can be seen as the largest geo-engineering project in which mankind has engaged, land system science can act as a platform for integration of insights from different disciplines and for translation of knowledge into action

Effect of Concrete Wasteform Properties on Radionuclide Migration

The objective of this investigation was to initiate numerous sets of concrete-soil half-cell tests to quantify 1) diffusion of I and Tc from concrete into uncontaminated soil after 1 and 2 years, 2) I and Re (set 1) and Tc (set 2) diffusion from fractured concrete into uncontaminated soil, and 3) evaluate the moisture distribution profile within the sediment half-cell. These half-cells will be section in FY2009 and FY2010. Additionally, 1) concrete-soil half-cells initiated during FY2007 using fractured prepared with and without metallic iron, half of which were carbonated using carbonated, were sectioned to evaluate the diffusion of I and Re in the concrete part of the half-cell under unsaturated conditions (4%, 7%, and 15% by wt moisture content), 2) concrete-soil half cells containing Tc were sectioned to measure the diffusion profile in the soil half-cell unsaturated conditions (4%, 7%, and 15% by wt moisture content), and 3) solubility measurements of uranium solid phases were completed under concrete porewater conditions. The results of these tests are presented

Interim Report: Uranium Stabilization Through Polyphosphate Injection - 300 Area Uranium Plume Treatability Demonstration Project

This report presents results from bench-scale treatability studies conducted under site-specific conditions to optimize the polyphosphate amendment for implementation of a field-scale technology demonstration to treat aqueous uranium within the 300 Area aquifer of the Hanford site. The general treatability testing approach consists of conducting studies with site sediment and under site conditions, in order to develop an effective chemical formulation for the polyphosphate amendments and evaluate the transport properties of these amendments under site conditions. Phosphorus-31 (31P) NMR was utilized to determine the effects of Hanford groundwater and sediment on the degradation of inorganic phosphates. Static batch tests were conducted to optimize the composition of the polyphosphate formulation for the precipitation of apatite and autunite, as well as to quantify the kinetics, loading and stability of apatite as a long-term sorbent for uranium. Dynamic column tests were used to further optimize the polyphosphate formulation for emplacement within the subsurface and the formation of autunite and apatite. In addition, dynamic testing quantified the stability of autunite and apatite under relevant site conditions. Results of this investigation provide valuable information for designing a full-scale remediation of uranium in the 300 aquifer

Biological, clinical and population relevance of 95 loci for blood lipids.

Plasma concentrations of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides are among the most important risk factors for coronary artery disease (CAD) and are targets for therapeutic intervention. We screened the genome for common variants associated with plasma lipids in >100,000 individuals of European ancestry. Here we report 95 significantly associated loci (P < 5 x 10(-8)), with 59 showing genome-wide significant association with lipid traits for the first time. The newly reported associations include single nucleotide polymorphisms (SNPs) near known lipid regulators (for example, CYP7A1, NPC1L1 and SCARB1) as well as in scores of loci not previously implicated in lipoprotein metabolism. The 95 loci contribute not only to normal variation in lipid traits but also to extreme lipid phenotypes and have an impact on lipid traits in three non-European populations (East Asians, South Asians and African Americans). Our results identify several novel loci associated with plasma lipids that are also associated with CAD. Finally, we validated three of the novel genes-GALNT2, PPP1R3B and TTC39B-with experiments in mouse models. Taken together, our findings provide the foundation to develop a broader biological understanding of lipoprotein metabolism and to identify new therapeutic opportunities for the prevention of CAD