archives@tulane.edu / Gestational diabetes mellitus (GDM) increases the lifetime risk of developing type 2 diabetes mellitus (T2DM) in the mother; however, biological mechanisms remain relatively unknown, and known risk factors have shown to be incomplete. Both epidemiological and experimental research suggest that environmental exposure to particulate matter (PM2.5) may initiate and further progress chronic diseases such as T2DM. This study investigates the association between PM2.5 exposure and the risk of T2DM among women with a history of GDM. Associations between prevalent and incident T2DM with PM2.5 utilized two PM2.5 metrics: 1) annual average PM2.5 concentration and 2) annual average modeled PM2.5 exposure, calculated from daily PM2.5 concentration levels provided by the USRA/NASA Marshal Space Flight Center. Data from the Southern Community Cohort Study, who at recruitment reported a previous diagnosis of GDM, for whom T2DM, risk factor, and follow-up information were available, was provided. In total, 2403 participants were included in the analysis of prevalent T2DM, and 1036 participants were included in the analysis of incident T2DM. Associations between proximity to roadways and race with PM2.5 metrics were also conducted. Participants that live close to roadways were exposed to higher annual average PM2.5 concentrations and annual average modeled PM2.5 exposures. When stratified by race, non-Black participants were exposed to higher averages. After adjustment, a significant association was observed between annual average PM2.5 concentration and incident T2DM (hazards ratio (HR)= 1.022, 95% confidence interval (CI): 1.003, 1.040). No association was observed between annual average PM2.5 concentrations and prevalent T2DM. Annual average modeled PM2.5 exposure was not associated with either prevalent or incident T2DM. Results were partly consistent with previous literature. Additional studies with a greater range of air pollution exposures, including higher levels, additional pollutants, and more tailored exposure models, are warranted to investigate hypothesized associations. / 0 / Ashley Bell

The fine and ultra fine size of diesel particulate mater (DPM) are of great health concern and significantly contribute to the overall cancer risk. In addition, diesel particles may contribute a warming effect on the planet's climate. The composition of these particles is composed principally of elemental carbon (EC) with adsorbed organic compounds, sulfate, nitrate, ammonia, metals, and other trace elements. The purpose of this study was to depict the seasonality and modeling of particulate matter in the Southeastern US produced by the diesel fueled sources (DFSs). The modeling results came from four one-month cases including March, June, September, and December to represent different seasons in 2003 by linking Models-3/CMAQ and SMOKE. The 1999 National Emissions Inventory Version 3 (NEI99) was used in this analysis for point, area, and non-road sources, whereas the National Mobile Inventory Model (NMIM) was used to create the on-road emissions. Three urban areas, Atlanta, Birmingham, and Nashville were selected to analyze the DPM emissions and concentrations. Even though the model performance was not very strong, it could be considered satisfactory to conduct seasonal distribution analysis for DPM. Important hourly DPM seasonality was observed in each city, of which higher values occurred at the morning traffic rush hours. The EC contributions of primary DPM were similar for all three sites (~ 74%). The results showed that there is no significant daily seasonality of DPM contribution to PM2.5 for any of these three cities in 2003. The annual DPM contribution to total PM2.5 for Atlanta, Nashville, and Birmingham were 3.7%, 2.5%, and 2.2%, respectively.

Indiana University-Purdue University Indianapolis (IUPUI) / This study looked at the time period of June through mid-October, 2013, based on the results of earlier studies that the strongest correlation between the PM2.5 and AOD data sets occurs during the summer and fall. Terra satellite data was used in this study due to availability of images for the geographic area of the state of Indiana during the time period of the study. PM2.5 measurements from 12 IDEM continuous monitoring sites, which were collected at noon local time, were compared with MODIS AOD data. Despite the limitations of useful data and smaller data sets, this study shows encouraging results, and illustrates that there is a relationship between remotely sensed MODIS AOD data and fine particulate matter (PM2.5) data collected from ground sensors within the geographic region of the state of Indiana. It is believed that this topic should be studied further and expanded upon.

The discharge of sediment-laden rivers into the Mississippi Sound increases the turbidity of coastal waters. The concentration of suspended particulates is an important parameter in the analysis of coastal water quality factors. The spatiotemporal resolution associated with satellite sensors makes remote sensing an ideal tool to monitor suspended particulate concentrations. Accordingly, the presented research evaluated the validity of published algorithms that relate remote sensing reflectance (Rrs) with suspended particulate matter for the Mississippi Sound. Additionally, regression analysis was used to correlate in situ SPM concentrations with coincident observations of visible and near-infrared band reflectance collected by the MODIS Aqua sensor in order to develop a predictive model for SPM. The most robust algorithm yielded an RMSE of 15.53% (n = 86) in the determination of SPM concentrations. The application of this algorithm allows for the rapid assessment of water quality issues related to elevated SPM concentrations in the Mississippi Sound.

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京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22060号 / 工博第4641号 / 新制||工||1724(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高野 裕久, 教授 米田 稔, 准教授 上田 佳代 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Three- different groups of materials were chosen to investigate the uniaxial compaction of particulate solids. Dentritic and cubic sodium chloride were chosen as plastically deforming, dicalcium phosphcte and sugar as fragmentary and styrocell, homopolymer and copolyrinier as non-compactable materials. The uniaxial compaction of the materials was continuously followed by measurement. of 1-.h e applied force, the force transmitted radially to the die wall and the upper punch displacement. The data obtained was presented in the form of Mohr circles, stress pathways (shear-mean compaction stress planes) and a three dimensional representation in mean compaction stress, shear stress and volume change. The yield loci evaluated from Mohr circles and shear-mean compaction stress relationships of compactable and non-compactable materials were found to be similar in shape. The unloading stress profiles were however more informative. All unloading shear-mean compaction stres's curves of the compactable materials cross the mean compaction stress axis to give negative values of shear stress and reach a minimum value of T min' which was material and compaction p.,- essure dependent. The unloading curves of non-compactable materials gaye approximately zero shear. The parameters evaluated from the characteristic stress profiles were correlated to the tensile strength and hardness of compacts. Mathematical expressions have been proposed for the shear-mean compaction stress relationships of the materials investigated. TI he materials were characterised before and after compaction in terms of specific surface aroa, porosity and mechanical strength of compacts with ccrnpaction pressure. / Sudan Government and the Institution of Chemical Engineers.

Exhaust emissions in a vehicle has to flow through an exhaust aftertreatment in a diesel vehicle. In a diesel engine, the exhaust emissions are treated with Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF), and Selective Catalytic Reduction (SCR). Every engine produces a different kind of soot depending on the drive cycle. In this thesis, a study was made on the soot oxidation in DPF so as to reduce the net fuel consumption and hence optimising the engine.This project focuses on DPF, where the soot and ash are trapped on the walls of the filter when the emissions flow through the DPF. Over a period of time, the soot accumulates and causes the pressure inside the filter to increase. To reduce the backpressure due to soot accumulation, soot has to be removed from the filter which is done by a regeneration process in which soot is oxidized. To understand the soot oxidation in the DPF, we study the chemical kinetics of the soot.The soot reacts with NO2, O2, and N2 in a Thermogravimetric Analysis (TGA) instrument, in isothermal conditions. Two soot samples, SORT-1 and FORCED 360 were analyzed with TGA, the rate equations were derived from using Arrhenius type kinetics and the data was processed by MATLAB. The rate at which the soot is oxidized by NO2 and O2 for SORT-1 is higher than for FORCED 360. This trend is observed similarly when both the soot samples react with only O2. When soot oxidation reaction takes place with O2 and NO2 they require a lower temperature of 250 °C-400 °C than compared to samples reacting with only O2 with a temperature of 350 °C - 500 °C. To understand the conditions that affect soot oxidation, the concentration of oxygen was varied and it was found that at higher oxygen concentration the soot oxidized is almost constant. Then soot kinetics were analysed by finding the rate of the reaction, the order of the reaction, and finally the activation energy. The order of the reaction for FORCED 360 and SORT-1 vary and slope of the graph, logarithm of reaction constant vs logarithm of mass shows a non-linearity in the former due to the slower rate of the reaction in SORT-1 than in FORCED 360. The activation energy was found to be 39.3 kJ/mol for SORT-1 and FORCED 360 is 60.8 kJ/mol. / Avgasutsläpp i ett fordon måste strömma genom avgasefterbehandling i ett dieselfordon. I en dieselmotor behandlas avgasutsläppen med dieseloxidationskatalysator (DOC), dieselpartikelfilter (DPF) och selektiv katalytisk reduktion (SCR). Varje motor producerar olika typer av sot beroende på körcykeln. I denna avhandling gjordes en undersökning av sotoxidationen i DPF för att minska nettobränsleförbrukningen och därmed optimera motorn. Detta projekt fokuserar på DPF, där sot och aska fångas på filterväggarna när utsläppen flyter genom dieselpartikelfiltret. Under en tidsperiod ackumuleras sot och får trycket inuti filtret att öka. För att minska mottrycket på grund av sotansamling måste sot avlägsnas från filtret, vilket görs genom en regenereringsprocess där sot oxideras. För att förstå sotoxidationen i DPF studerar vi sotens kemiska kinetik. Sotet reagerar med NO2, O2 och N2 i ett instrument för termogravimetrisk analys (TGA) under isotermiska förhållanden. Två sotprover, SORT-1 och FORCED 360 analyserades med TGA, hastighetsekvationerna härleddes från användning av Arrhenius-typskinetik och data bearbetades av MATLAB. Den hastighet med vilken sot oxideras av NO2 och O2 för SORT-1 är högre än för FORCED 360. Denna trend observeras på liknande sätt när båda sotproverna reagerar med endast O2. När reaktion genom sotoxidation äger rum med O2 och NO2 kräver de en lägre temperatur på 250 ° C - 400 ° C än jämfört med prover som bara reagerar med O2 med en temperatur på 350 ° C - 500 ° C. För att förstå de förhållanden som påverkar sotoxidation varierades syrekoncentrationen och det visade sig att vid högre syrekoncentration var sotet oxiderat nästan konstant. Därefter analyserades sotkinetiken genom att hitta reaktionshastigheten, reaktionsordningen och slutligen aktiveringsenergin. Reaktionsordningen för FORCED 360 och SORT-1 varierar och lutningen i diagrammet, logaritmen för reaktionskonstanten mot logaritmen av massan visar en icke-linjäritet i den tidigare på grund av den långsammare reaktionshastigheten i SORT-1 än i FORCED 360. Aktiveringsenergin konstaterades vara 39,3 kJ / mol för SORT-1 och för FORCED 360, 60,8 kJ / mol.

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