Online Single Particle Chemical Characterization Of Aerosol Populations in Remote Environments

Atmospheric aerosols have significant impacts on air quality, climate, and human health, yet analytical and logistical challenges have limited our ability to measure these aerosol particles, particularly in remote regions. In this dissertation, individual atmospheric particles were chemically characterized in rural northern Michigan and remote northern Alaska for the first time. To enable this measurements, Chapter 2 details the construction and characterization of an updated aircraft-capable aerosol time-of-flight mass spectrometer (A-ATOFMS), capable of measuring size-resolved chemical composition of 0.07 – 1.6 µm individual particles up to 40 Hz with lower mass (~25 kg saved) and power (~600 W saved) consumption than the previous A-ATOFMS. Chapter 3 discusses size-resolved chemical composition of atmospheric aerosols in northern Michigan while the site was influenced by Canadian wildfire, urban, and local forest air masses. Throughout the study, long-range transported biomass burning aerosols were the cores of particles primarily consisting, by mass, of secondary organic aerosol from the oxidation of volatile organic compounds emitted from both wildfires and forests. In Chapter 4, we identified 14 periods of ultrafine particle growth at the same field site. Urban air mass influence during the daytime led to the highest observed growth rates, likely due to increased atmospheric oxidant levels producing condensable material. Nighttime wildfire air masses were likely influenced by increased SO2 and NO2 in the plumes leading to NO3 radical oxidation. TEM-EDX showed contributions from sulfur, carbon, and oxygen down to 20 nm particles, suggesting contributions from H2SO4 and SOA. As particle growth was previously thought to be suppressed in this isoprene-rich forest, these measurements represent a source of particles not previously considered in this environment. Chapters 5 – 6 discuss the results from field campaigns conducted in the Alaskan Arctic. In Chapter 5, I show results of A-ATOFMS and scanning electron microscopy with energy-dispersive x-ray spectroscopy (SEM-EDX) analyses of atmospheric particles transported to Utqiaġvik, AK from the Prudhoe Bay oil fields, located hundreds of kilometers to the east, in comparison to the pristine Arctic Ocean background. During Arctic Ocean influence, fresh sea spray aerosol (SSA) was the primary contributor to aerosol number concentrations, compared to transported organic carbon and aged SSA particles during Prudhoe Bay air masses. Chapter 6 details the 2016 field campaign within the Prudhoe Bay oil fields, where we deployed the A-ATOFMS to characterize local oil field combustion plumes and the overall oil field background aerosol population; these were the first single particle measurements within an Arctic oil field. Diesel and natural gas combustion were the major influences on the aerosol population, with unique amine-containing particles identified from the processing of natural gas. Overall, the results from these field campaigns, aided by the newly constructed A-ATOFMS, provided new insights into the chemical composition of local and transported atmospheric particles on rural and remote environments influenced by the changing climate.PHDChemistryUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/140981/1/gunsch_1.pd

The Effect of Wetland Size and Surrounding Land Use on Wetland Quality Along an Urbanization Gradient in the Rocky River Watershed

An intensive floristic evaluation of 17 Cleveland Metroparks (CMP) wetlands in the Rocky River Watershed (RRW) was undertaken to determine whether wetland size or anthropogenic disturbance in the surrounding landscape is a better predictor of wetland quality in this protected parkland. Wetland study sites were selected in three reservations, Hinckley, Mill Stream Run, and Rocky River. My research adds valuable information to the CMP wetland database and will contribute to its wetland management policies. Wetland quality was determined using the following floristic indices: species richness, non-native species, wetland species, mean coefficient of conservatism (C of C), floristic quality assessment index (FQAI), and an FQAI weighted with the wetland indicator status (FQAI-WIS). Wetland perimeter and area were calculated from shape files created by a 12-channel global positioning system (GPS) receiver and data logger. The extent of anthropogenic disturbance was measured within 100 m, 250 m, 500 m, and 1000 m buffers surrounding the wetlands using a landscape development intensity (LDI) index. This LDI index was based on 1) the percentage of each land use and land cover (LULC) category found in the buffer zones and 2) LDI coefficients for each LULC category that reflect the amount of energy associated with human activities. Linear regressions (p = 0.05) were run to evaluate the relationship between the predictor variables (perimeter, area, perimeter/area ratio, and LDI) and the response variables (floristic indices). Results showed a significant positive correlation between wetland species and perimeter. However, when the site with the largest perimeter was removed from the data set, this correlation no longer existed. Results also showed a significant negative correlation between 1) mean coefficient of conservatism and 250 m LDI, 2) FQAI and 250 m LDI, 3) FQAI and 500 m LDI, and 4) FQAI-WIS and 250 m LDI. While these regressions were significant, the R2 range from 0.27 to 0.31 indicated weak correlations

The Effect of Wetland Size and Surrounding Land Use on Wetland Quality Along an Urbanization Gradient in the Rocky River Watershed

An intensive floristic evaluation of 17 Cleveland Metroparks (CMP) wetlands in the Rocky River Watershed (RRW) was undertaken to determine whether wetland size or anthropogenic disturbance in the surrounding landscape is a better predictor of wetland quality in this protected parkland. Wetland study sites were selected in three reservations, Hinckley, Mill Stream Run, and Rocky River. My research adds valuable information to the CMP wetland database and will contribute to its wetland management policies. Wetland quality was determined using the following floristic indices: species richness, non-native species, wetland species, mean coefficient of conservatism (C of C), floristic quality assessment index (FQAI), and an FQAI weighted with the wetland indicator status (FQAI-WIS). Wetland perimeter and area were calculated from shape files created by a 12-channel global positioning system (GPS) receiver and data logger. The extent of anthropogenic disturbance was measured within 100 m, 250 m, 500 m, and 1000 m buffers surrounding the wetlands using a landscape development intensity (LDI) index. This LDI index was based on 1) the percentage of each land use and land cover (LULC) category found in the buffer zones and 2) LDI coefficients for each LULC category that reflect the amount of energy associated with human activities. Linear regressions (p = 0.05) were run to evaluate the relationship between the predictor variables (perimeter, area, perimeter/area ratio, and LDI) and the response variables (floristic indices). Results showed a significant positive correlation between wetland species and perimeter. However, when the site with the largest perimeter was removed from the data set, this correlation no longer existed. Results also showed a significant negative correlation between 1) mean coefficient of conservatism and 250 m LDI, 2) FQAI and 250 m LDI, 3) FQAI and 500 m LDI, and 4) FQAI-WIS and 250 m LDI. While these regressions were significant, the R2 range from 0.27 to 0.31 indicated weak correlations

The Defiance College Undergraduate Major in Digital Forensic Science: Setting the Bar Higher

This paper provides background information to accompany the panel discussion on Curriculum Design and Implementation in Computer Forensics Education. It is specifically focused on the content and delivery of Defiance College’s undergraduate (B.S.) program majoring in Digital Forensic Science (DFS). The genesis and evolution of the Defiance College DFS program are described, along with its successes, challenges and known opportunities for improvement. The desired outcomes of the panel discussion include articulating the necessary components of an undergraduate program, refining expectations of knowledge and skills required of students upon graduation, and suggesting strategies for achieving those expectations despite inevitable resource limitations and diverse student demographics. Keywords: education, undergraduate, digital forensics, computer forensics, pedagogy, skills developmen

Community Composition of Aquatic Invertebrates along Dissolved Oxygen Gradients in Lake Huron Coastal Wetland Wet Meadows

Wetlands are an ecotone between terrestrial and aquatic environments and therefore support a diverse and unique flora and fauna. Macroinvertebrates make up a substantial portion of the biodiversity. The relationship between aquatic invertebrate community composition and the association with submergent and emergent macrophyte biomass is relatively well documented. However, the constraints imposed by conditions in wet meadow zones – areas that are intermittently flooded but whose soils are typically water-saturated and anoxic are less well understood. I investigated the relative importance of dissolved oxygen along the water depth gradient and its influenced on invertebrate community composition in comparison to the uniform vegetation found in the wet meadow zones of 10 wetlands in Lake Huron of the Laurentian Great Lakes.In 2017, I evaluated macrophyte community composition, sampled zoobenthos and fishes, and recorded diel dissolved oxygen trends along multiple transects in 10 coastal wetland wet meadows varying in geomorphology and exposure to agricultural activity in the contributing watersheds. The duration of hypoxia (DO \u3c 4.0 mg/L) was a negative function of water depth along 30-m transects varying from 30-100 cm deep within each wet meadow site. Differences in the environmental factors were reflected in the relative abundance of oxygen-sensitive zoobenthos, being greater in areas that experienced a shorter duration of diel hypoxia and anoxia. However, overall invertebrate community composition was most greatly influenced by the major environmental differences between ecoregions and among wetlands within ecoregions. Thus, wet meadow community composition can be inferred from synoptic benthic samples collected from a wetland without concern for biases related to sampling depth

Comparação entre técnicas de IA e desenvolvimento de um filtro de mensagens

TCC(graduação) - Universidade Federal de Santa Catarina. Centro Tecnológico. Engenharia de Controle e Automação.O presente trabalho foi realizado na empresa Cellmídia, fundada e com sede em Florianópolis, nele é apresentado o serviços oferecidos pela empresa, que fazem parte do escopo do trabalho. Também é apresentado de forma superficial o a teoria de Inteligência Artificail, bem como os algumas metodologias referentes ao assunto, para que o leitor leigo nessa área possa entender o trabalho por completo. No desenvolvimento do trabalho é apresentado a implementação de dois classificadores de mensagens, um baseado na teoria de Árvore de decsão e outro em Redes Bayesianas. Seguindo de uma resultado comparativo entre as duas metodologias. Finalizando o trabalho temos os resultados de todo o trabalho desenvolvido, assim também como as conclusões e perpectivas futuras referentes ao desenvolvimento realizado.This work was carried out in the company Cellmídia, founded and based in Florianopolis, it presents the services offered by the company, forming part of the scope of work. Is also presented in a superficial way the the theory Artificail Intelligence, as well as some methodologies pertinent to the discussion for the lay reader can understand this area work altogether. In developing this work is presented the implementation of two classifiers messages, based on the theory of a tree and another decsão Baysianas Network. Following a comparative result between the two methodologies. Finishing the job we have the results of all the work, also the conclusions and future perspectives for the development to be performed

Contributions of transported Prudhoe Bay oil field emissions to the aerosol population in Utqiaġvik, Alaska

Loss of sea ice is opening the Arctic to increasing development involving oil and gas extraction and shipping. Given the significant impacts of absorbing aerosol and secondary aerosol precursors emitted within the rapidly warming Arctic region, it is necessary to characterize local anthropogenic aerosol sources and compare to natural conditions. From August to September 2015 in Utqiaġvik (Barrow), AK, the chemical composition of individual atmospheric particles was measured by computer-controlled scanning electron microscopy with energy-dispersive X-ray spectroscopy (0.13-4 μm projected area diameter) and real-time single-particle mass spectrometry (0.2-1.5 μm vacuum aerodynamic diameter). During periods influenced by the Arctic Ocean (70 % of the study), our results show that fresh sea spray aerosol contributed ∼ 20 %, by number, of particles between 0.13 and 0.4 μm, 40-70 % between 0.4 and 1 μm, and 80-100 % between 1 and 4 μm particles. In contrast, for periods influenced by emissions from Prudhoe Bay (10 % of the study), the third largest oil field in North America, there was a strong influence from submicron (0.13-1 μm) combustion-derived particles (20-50 % organic carbon, by number; 5-10 % soot by number). While sea spray aerosol still comprised a large fraction of particles (90 % by number from 1 to 4 μm) detected under Prudhoe Bay influence, these particles were internally mixed with sulfate and nitrate indicative of aging processes during transport. In addition, the overall mode of the particle size number distribution shifted from 76 nm during Arctic Ocean influence to 27 nm during Prudhoe Bay influence, with particle concentrations increasing from 130 to 920 cm-3 due to transported particle emissions from the oil fields. The increased contributions of carbonaceous combustion products and partially aged sea spray aerosol should be considered in future Arctic atmospheric composition and climate simulations