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This dataset includes elemental stoichiometry for Emiliania huxleyi across a range of 12 temperatures from 8.5-28.6C. Global warming will be combined with predicted increases in thermal variability in the future surface ocean, but how temperature dynamics will affect phytoplankton biology and biogeochemistry is largely unknown. Here, we examine the responses of the globally important marine coccolithophore Emiliania huxleyi to thermal variations at two frequencies (1 d and 2 d) at low (18.5 °C) and high (25.5 °C) mean temperatures. Elevated temperature and thermal variation decreased growth, calcification and physiological rates, both individually and interactively. The 1 d thermal variation frequencies were less inhibitory than 2 d variations under high temperatures, indicating that high-frequency thermal fluctuations may reduce heat-induced mortality and mitigate some impacts of extreme high-temperature events. Cellular elemental composition and calcification was significantly affected by both thermal variation treatments relative to each other and to the constant temperature controls. The negative effects of thermal variation on E. huxleyi growth rate and physiology are especially pronounced at high temperatures. These responses of the key marine calcifier E. huxleyi to warmer, more variable temperature regimes have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate.

Vanadium oxide has emerged as a potential electrochemical capacitor material due to its attractive pseudocapacitive performance; however, it is known to suffer from capacitive degradation upon sustained cycling. In this work, the electrochemical cycling behavior of anodically electrodeposited vanadium oxide films with various surface treatments in aqueous solutions is investigated at different pH. Quantitative compositional analysis and morphological studies provide additional insight into the mechanism responsible for capacitive degradation. Furthermore, the capacitance and impedance behavior of vanadium oxide electrochemical capacitor electrodes is compared for both aqueous and nonaqueous electrolyte-solvent systems. Alkali metal chloride and bromide electrolytes were studied in aqueous systems, and nonaqueous systems containing alkali metal bromides were studied in polar aprotic propylene carbonate (PC) or dimethyl sulfoxide (DMSO) solvents. The preferred aqueous and nonaqueous systems identified in the half-cell studies were utilized in symmetric vanadium oxide whole-cells. An aqueous system utilizing a 3.0 M NaCl electrolyte at pH 3.0 exhibited an excellent 96% capacitance retention over 3000 cycles at 10 mV s-1. An equivalent system tested at 500 mV s-1 displayed an increase in capacitance over the first several thousands of cycles, and eventually stabilized over 50,000 cycles. Electrodes cycled in nonaqueous 1.0 M LiBr in PC exhibited mostly non-capacitive charge-storage, and electrodes cycled in LiBr-DMSO exhibited a gradual capacitive decay over 10,000 cycles at 500 mV s-1. Morphological and compositional analyses, as well as electrochemical impedance modeling, provide additional insight into the cause of the cycing behavior. Lastly, reduced graphene oxide and vanadium oxide nanowire composites have been successfully synthesized using electrophoretic deposition for electrochemical capacitor electrodes. The composite material was found to perform with a higher capacitance than electrodes containing only vanadium oxide nanowires by a factor of 4.0 at 10 mV s-1 and 7.5 at 500 mV s-1. The thermally reduced composite material was examined in both symmetric and asymmetric whole cell electrochemical capacitor devices, and although the asymmetric cell achieved both higher energy and power density, the symmetric cell retained a higher capacitance over 50,000 cycles at 200 mV s-1.

Overview This dataset contains the following data and results: (1) National age-adjusted and age-invariant VSL estimates in 2019. (2) Global, regional, income-group, and national source-specific fractional contributions to PM2.5, health costs, and disparities estimated using both MR-BRT and GEMM CRFs, along with classifications of each country into different regions and income groups. (3) National total deaths and health costs, as well as source-specific deaths and costs using both MR-BRT and GEMM CRFs. (4) Gridded fractional source contributions to health costs from ambient PM2.5. The methodology and analysis of these results are described in the following article: Hao Yin, Erin McDuffie, Randall Martin, Michael Brauer, Global Health Costs of Ambient PM2.5 from Combustion Sources: A Modelling Study Supporting Air Pollution Control Strategies. Lancet Planetary Health. https://doi.org/10.1016/S2542-5196(24)00098-6 Data File Descriptions File “1 - Age-adjusted and age-invariant VSL.xlsx” documents age-adjusted and age-invariant VSL estimates for 204 countries in 2019. File “2 - Source-specific fractional contributions to PM2.5, health costs, and disparities.xlsx” summarizes global, regional, income-group, and national source-specific fractional contributions to PM2.5, health costs, and disparities estimated using both MR-BRT and GEMM CRFs, along with classifications of each country into different regions and income groups. File “3 - National total and source-specific deaths and health costs.xlsx” includes national total deaths and health costs, as well as source-specific deaths and costs using both MR-BRT and GEMM CRFs. The raster files for gridded fractional source contributions to health costs from ambient PM2.5 include multiple layers. The first raster file, "4-gridded_health_cost_fuel_vsl_age_contribution.tif" documents the gridded individual source contribution to health costs estimated using the age-adjusted VSL measure at a resolution of 0.01°x0.01°. The second raster file, "5-gridded_health_cost_fuel_vsl_contribution.tif" documents the gridded individual source contribution to health costs estimated using the age-invariant VSL measure at the same resolution. The layer names in these files (#4 and #5) are as follows: (1) Base (all sources included) (2) Solid biofuel (3) Total coal (4) Liquid fuel and natural gas (5) Windblown dust (6) AFCID (AFCID dust) (7) Agricultural waste burning (8) Other fires (9) Other sources The raster file "6-gridded_health_cost_comb_noncomb_vsl_age_contribution.tif " documents the gridded contributions of combustion and non-combustion sources to health costs from PM2.5 using the age-adjusted VSL measure. The raster file "7-gridded_health_cost_comb_noncomb_vsl_contribution.tif" documents the gridded contributions of combustion and non-combustion sources to health costs from PM2.5 using the age-invariant VSL measure. These two raster files (#6 and #7) contain three layers: (1) Base (all sources included) (2) Combustion sources (3) Non-combustion sources For more detailed information on the source definition, please refer to our paper. Hao Yin, Erin McDuffie, Randall Martin, Michael Brauer, Global Health Costs of Ambient PM2.5 from Combustion Sources: A Modelling Study Supporting Air Pollution Control Strategies. Lancet Planetary Health. https://doi.org/10.1016/S2542-5196(24)00098-6

This dataset presents growth rates for Emiliania huxleyi thermal response curve across 12 temperatures from 8.5-28.6C.Global warming will be combined with predicted increases in thermal variability in the future surface ocean, but how temperature dynamics will affect phytoplankton biology and biogeochemistry is largely unknown. Here, we examine the responses of the globally important marine coccolithophore Emiliania huxleyi to thermal variations at two frequencies (1 d and 2 d) at low (18.5 °C) and high (25.5 °C) mean temperatures. Elevated temperature and thermal variation decreased growth, calcification and physiological rates, both individually and interactively. The 1 d thermal variation frequencies were less inhibitory than 2 d variations under high temperatures, indicating that high-frequency thermal fluctuations may reduce heat-induced mortality and mitigate some impacts of extreme high-temperature events. Cellular elemental composition and calcification was significantly affected by both thermal variation treatments relative to each other and to the constant temperature controls. The negative effects of thermal variation on E. huxleyi growth rate and physiology are especially pronounced at high temperatures. These responses of the key marine calcifier E. huxleyi to warmer, more variable temperature regimes have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate.

Buildings account for over 18% of the world's anthropogenic Greenhouse Gas (GHG) emissions. As a result, a technology that can offset GHG emissions associated with buildings has the potential to save over 9 Giga-tons of GHG emissions per year. High temperature fuel cell and absorption chiller (HTFC/AC) technology offers a relatively low-carbon option for meeting cooling and electric loads for buildings while producing almost no criteria pollutants. GHG emissions in the state of California would decrease by 7.48 million metric tons per year if every commercial building in the State used HTFC/AC technology to meet its power and cooling requirements. In order to realize the benefits of HTFC/AC technology on a wide scale, the distributed generation market needs to be exposed to the technology and informed of its economic viability and real-world potential. This work characterizes the economics associated with HTFC/AC technology using select scenarios that are representative of realistic applications. The financial impacts of various input factors are evaluated and the HTFC/AC simulations are compared to the economics of traditional building utilities. It is shown that, in addition to the emissions reductions derived from the systems, HTFC/AC technology is financially preferable in all of the scenarios evaluated. This work also presents the design of a showcase environment, centered on a beta-test application, that presents (1) system operating data gathered using a custom data acquisition module, and (2) HTFC/AC technology in a clear and approachable manner in order to serve the target audience of market stakeholders.

Walking is the main mode of transportation for many of the world's people, particularly those in cities of the majority world. In the metropolitan region of Jakarta, walking in the public realm constitutes the main transportation mode for almost 40 percent of trips--a massive contribution to urban mobility. On the other hand, there is no comprehensive planning for pedestrians in an analogous manner to other modes of transportation. Pedestrian facilities are often dilapidated, damaged, dangerous, or missing completely. Additionally, there is no process for assessing the inventory of pedestrian facilities, planning pedestrian facilities at a region-wide level, or even identifying the location of vernacular pedestrian routes in low-income and informal areas. Provincial pedestrian planning focuses on piecemeal, symbolic spaces such as monumental plazas that serve the nation-building project, but overlooks the functional network of routes that address the daily needs of the city's residents. This dissertation examines the issue of walkability planning in Jakarta by investigating what matters to pedestrians and how pedestrian space is produced. The research employs mixed methods, including pedestrian network groundtruthing, structured streetscape observations, multimodal traffic counts, pedestrian activity mapping, pedestrian surveys and interviews with policy-makers. Data is analyzed through a combination of in-depth qualitative analysis as well as quantitative and statistical analysis. Based on this research, six key elements of walkability planning are proposed for Jakarta: multidisciplinarity, ethnography, accessibility, legibility, integrated activity, and shared streets. A literature review of walkability metrics reveals that walking is a highly multidisciplinary activity, with very different metrics emerging from different fields. In order to effectively encourage pedestrian activity, new multidisciplinary metrics should integrate the perspectives of all of these related disciplines and pedestrian planning should occur through inter-agency coordination. In Jakarta, interviews with policy-makers suggested that pedestrian planning is hindered by the fact that there is no lead agency for pedestrian planning, and there is a lack of cooperation between the different agencies that plan and produce urban public space. Pedestrian planning is also hindered by a discursive framework that is both modally and geographically biased--favoring motorized, long-distance modes of transportation and employing method derived from a Western research and planning norms. In order to overcome this discursive bias, ethnography should become a standard part of urban research, planning and design. The need for ethnography and qualitative analysis was made visible by the mismatch between standard transportation terminology, and prevailing practices observed in pedestrian mapping exercises and raised by pedestrians in on-the-street interviews. For example, standard survey categories do not account for informal or integrated activity patterns like mobile street vending. From surveys conducted with mobile street vendors, it was difficult to separate their pedestrian activities into categories of travel from home to work, business-related travel, and visiting friends and relatives. In fact, it was difficult to even separate their travel from their activities since many vendors carried out business as they made their way through the neighborhood. With a large portion of the population engaged in the informal sector, the discrepancy between assumed and actual behavior severely compromises the quality of transportation-related research that is conducted in Jakarta and many other majority world cities. Ethnographic and qualitative research methods may therefore assist in producing more context-sensitive planning data and outcomes. These context-sensitive methods could include new analytical methods that focus on integrated activity, rather than trip-based or activity-based analysis. In relation to pedestrian activity, context-sensitive planning encompasses new approaches to accessibility that combine the notion of transportation accessibility with disabled access and universal access standards. The need for such an approach was revealed during interviews with policy-makers, who described accessibility in terms of market goods rather than human rights. Within the market for urban public space, ordinary pedestrians were unable to compete with other modes of transportation; within the market for urban impressions, ordinary pedestrian spaces were outcompeted by prominent, symbolic spaces; and within the market for cultural capital, ordinary pedestrians were excluded from planning processes because even the discourse of pedestrian planning was inaccessible to regular residents. In response to this problem of exclusion, integrated accessibility may facilitate inclusion in both planning processes and urban spaces within the city. In particular, integrated accessibility would aim to provide comprehensive routes of travel for all pedestrians, rather than isolated pockets of so-called accessible (yet unreachable) facilities. More context sensitive planning would also be facilitated through greater legibility of fine-grained and vernacular pedestrian networks that were missing from standard planning maps. These fine-grained networks represent highly connected facilities that serve much of Jakarta's pedestrian transportation task. While the current synoptic illegibility of these areas may conveniently allow some communities to avoid state intrusion, it also means that low-income populations are chronically underserved with respect to basic urban planning and services. Increased legibility therefore allows for improvement and maintenance of urban systems like safe, functional pedestrian networks, and it may also play a role in increasing tenure security for Jakarta's significant floating population. In many of these vernacular spaces, new street design approaches would also benefit pedestrians, who tend to use the streets as shared spaces, rather than spaces that are rigidly segregated by mode. Pedestrian activity mapping revealed that only an overwhelming majority of pedestrians used streets as hybrid spaces, with activity types falling into the categories of surface-sensitive, risk-averse, distance-minimizing and stationary pedestrians. More realistic shared street designs would therefore accommodate--rather than ignore--the types of activities that occur along Jakartan streets. Design standards for "great streets" in Jakarta would also emphasize the safe sharing of streets through self-enforcing approaches to speed limits, and the integration of various urban elements like drainage, mobility and public-private interaction. While walkability planning in Jakarta displays many "wicked problem" features, there is much that can be done to improve, if not resolve, conditions for pedestrians within the region. Recommended strategies for walkability planning in Jakarta include a regional walkability plan and environmental policy developed using participatory planning, reformed governance and institutional arrangements, and a constituency building approach. The strategies also include expansion of road designations and an integrated accessibility strategy that draws upon new data sources from a WikiPlaces network map, an integrated activity study and pedestrian network cost-benefit analysis. In addition to Jakarta-specific proposals, a number of proposals are made to advance discourse on walkability more generally. These approaches include decentered analysis of integrated activity, informal economic activity analysis, vernacular placemaking and Asian shared street design. Pedestrians and pedestrian plans traverse diverse physical, administrative and disciplinary spaces in cities of the world. Integrated and multidisciplinary approaches are therefore required to understand and accommodate these key users of public space. In Jakarta, walkability planning has potential to improve urban transportation efficiency while contributing to traffic safety, economic vitality, environmental quality and democratic governance. Successful walkability planning in Jakarta may also provide a model for planning in other cities where Western models of planning are unrealistic, inequitable and inappropriate. Jakartan lessons on walkability planning are particularly relevant, and improvements in walkability are particularly powerful, for cities characterized by relatively low median incomes, high land use densities, a substantial informal sector, rapid urbanization and rapid motorization. By improving walkability planning in Jakarta and other cities of the majority world, policy-makers and planners can move toward more sustainable, socially equitable and efficient cities.

The goal of the work in this dissertation is to understand and overcome the limiting optoelectronic processes in emerging second generation photovoltaic devices. There is an urgent need to mitigate global climate change by reducing greenhouse gas emissions. Renewable energy from photovoltaics has great potential to reduce emissions if the energy to manufacture the solar cell is much lower than the energy the solar cell generates. Two emerging thin film solar cell materials, organic semiconductors and hybrid organic-inorganic perovskites, meet this requirement because the active layers are processed at low temperatures, e.g. 150 °C. Other advantages of these two classes of materials include solution processability, composted of abundant materials, strongly light absorbing, highly tunable bandgaps, and low cost.Organic solar cells have evolved significantly from 1% efficient devices in 1989 to 11% efficient devices today. Although organic semiconductors are highly tunable and inexpensive, the main challenges to overcome are the large exciton binding energies and poor understanding of exciton dynamics. In my thesis, I optimized solar cells based on three new solution processable azadipyrromethene-based small molecules. I used the highest performing molecule to study the effect of increasing the permittivity of the material by incorporating a high permittivity small molecule into the active layer. The studies on two model systems, small donor molecules and a polymer-fullerene bulk heterojunction, show that Frenkel and charge transfer exciton binding energies can be manipulated by controlling permittivity, which impacts the solar cell efficiency.Hybrid organic-inorganic perovskite materials have similar advantages to organic semiconductors, but they are not excitonic, which is an added advantage for these materials. Although photovoltaics based on hybrid halide perovskite materials have exceeded 20% efficiency in only a few years of optimization, the loss mechanisms are not understood but critical to systematically improve the efficiency towards the theoretical limit. Thus, I correlated morphology to local power conversion efficiency determining properties by mapping local short circuit current, open circuit voltage, and dark drift current in state-of-the-art methylammonium lead iodide solar cells with sub-30 nm spatial resolution using photoconductive atomic force microscopy. I found, within individual grains, spatially-correlated heterogeneity in short circuit current and open circuit voltage. This heterogeneity is attributed to a facet-dependent density of trap states. These results imply that controlling crystal grain and facet orientation will enable a systematic optimization of hybrid halide perovskite photovoltaics.

Researchers installed radon mitigation systems in 12 houses in Spokane, Washington and Coeur d'Alene, Idaho during the heating season 1985--1986 and continued to monitor indoor radon quarterly and annually for ten years. The mitigation systems included active sub-slab ventilation, basement over-pressurization, and crawlspace isolation and ventilation. The occupants reported various operational problems with these early mitigation systems. The long-term radon measurements were essential to track the effectiveness of the mitigation systems over time. All 12 homes were visited during the second year of the study, while a second set 5 homes was visited during the fifth year to determine the cause(s) of increased radon in the homes. During these visits, the mitigation systems were inspected and measurements of system performance were made. Maintenance and modifications were performed to improve system performance in these homes.