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- All Subjects: Particulate matter
- All Subjects: Biochemistry
Description
Americans spend upwards of 90% of their time indoors, hence indoor air quality (IAQ) and the impact of IAQ on human health is a major public health concern. IAQ can be negatively impacted by outdoor pollution infiltrating indoors, the emission of indoor pollutants, indoor atmospheric chemistry and poor ventilation. Energy saving measures like retrofits to seal the building envelope to prevent the leakage of heated or cooled air will impact IAQ. However, existing studies have been inconclusive as to whether increased energy efficiency is leading to detrimental IAQ. In this work, field campaigns were conducted in apartment homes in Phoenix, Arizona to evaluate IAQ as it relates to particulate matter (PM), carbonyls, and tobacco specific nitrosamines (TSNA).
To investigate the impacts of an energy efficiency retrofit on IAQ, indoor and outdoor air quality sampling was carried out at Sunnyslope Manor, a city-subsidized senior living apartment complex. Measured indoor formaldehyde levels before the building retrofit exceeded reference exposure limits, but in the long term follow-up sampling, indoor formaldehyde decreased for the entire study population by a statistically significant margin. Indoor PM levels were dominated by fine particles and showed a statistically significant decrease in the long term follow-up sampling within certain resident subpopulations (i.e. residents who reported smoking and residents who had lived longer at the apartment complex). Additionally, indoor glyoxal and methylglyoxal exceeded outdoor concentrations, with methylglyoxal being more prevalent pre-retrofit than glyoxal, suggesting different chemical pathways are involved. Indoor concentrations reported are larger than previous studies. TSNAs, specifically N'-nitrosonornicotine (NNN), 4-(methyl-nitrosamino)-4-(3-pyridyl)-butanal (NNA) and 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone (NNK) were evaluated post-retrofit at Sunnyslope Manor. Of the units tested, 86% of the smoking units and 46% of the non-smoking units had traces of at least one of the nitrosamines.
To investigate the impacts of an energy efficiency retrofit on IAQ, indoor and outdoor air quality sampling was carried out at Sunnyslope Manor, a city-subsidized senior living apartment complex. Measured indoor formaldehyde levels before the building retrofit exceeded reference exposure limits, but in the long term follow-up sampling, indoor formaldehyde decreased for the entire study population by a statistically significant margin. Indoor PM levels were dominated by fine particles and showed a statistically significant decrease in the long term follow-up sampling within certain resident subpopulations (i.e. residents who reported smoking and residents who had lived longer at the apartment complex). Additionally, indoor glyoxal and methylglyoxal exceeded outdoor concentrations, with methylglyoxal being more prevalent pre-retrofit than glyoxal, suggesting different chemical pathways are involved. Indoor concentrations reported are larger than previous studies. TSNAs, specifically N'-nitrosonornicotine (NNN), 4-(methyl-nitrosamino)-4-(3-pyridyl)-butanal (NNA) and 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone (NNK) were evaluated post-retrofit at Sunnyslope Manor. Of the units tested, 86% of the smoking units and 46% of the non-smoking units had traces of at least one of the nitrosamines.
ContributorsFrey, Sarah E (Author) / Herckes, Pierre (Thesis advisor) / Fraser, Matthew P (Thesis advisor) / Destaillats, Hugo (Committee member) / Chizmeshya, Andrew (Committee member) / Arizona State University (Publisher)
Created2014
Description
Lipids perform functions essential to life and have a variety of structures that are influenced by the organisms and environments that produced them. Lipids tend to resist degradation after cell death, leading to their widespread use as biomarkers in geobiology, though their interpretation is often tricky. Many lipid structures are shared among organisms and function in many geochemical conditions and extremes. I argue it is useful to interpret lipid distributions as a balance of functional necessity and energy cost. This work utilizes a quantitative thermodynamic framework for interpreting energetically driven adaptation in lipids.
Yellowstone National Park is a prime location to study biological adaptations to a wide range of temperatures and geochemical conditions. Lipids were extracted and quantified from thermophilic microbial communities sampled along the temperature (29-91°C) and chemical gradients of four alkaline Yellowstone hot springs. I observed that decreased alkyl chain carbon content, increased degree of unsaturation, and a shift from ether to ester linkage caused a downstream increase in the average oxidation state of carbon (ZC) I hypothesized these adaptations were selected because they represent cost-effective solutions to providing thermostable membranes.
This hypothesis was explored by assessing the relative energetic favorability of autotrophic reactions to form alkyl chains from known concentrations of dissolved inorganic species at elevated temperatures. I found that the oxidation-reduction potential (Eh) predicted to favor formation of sample-representative alkyl chains had a strong positive correlation with Eh calculated from hot spring water chemistry (R2 = 0.72 for the O2/H2O redox couple). A separate thermodynamic analysis of bacteriohopanepolyol lipids found that predicted equilibrium abundances of observed polar headgroup distributions were also highly correlated with Eh of the surrounding water (R2= 0.84). These results represent the first quantitative thermodynamic assessment of microbial lipid adaptation in natural systems and suggest that observed lipid distributions represent energetically cost-effective assemblages along temperature and chemical gradients.
Yellowstone National Park is a prime location to study biological adaptations to a wide range of temperatures and geochemical conditions. Lipids were extracted and quantified from thermophilic microbial communities sampled along the temperature (29-91°C) and chemical gradients of four alkaline Yellowstone hot springs. I observed that decreased alkyl chain carbon content, increased degree of unsaturation, and a shift from ether to ester linkage caused a downstream increase in the average oxidation state of carbon (ZC) I hypothesized these adaptations were selected because they represent cost-effective solutions to providing thermostable membranes.
This hypothesis was explored by assessing the relative energetic favorability of autotrophic reactions to form alkyl chains from known concentrations of dissolved inorganic species at elevated temperatures. I found that the oxidation-reduction potential (Eh) predicted to favor formation of sample-representative alkyl chains had a strong positive correlation with Eh calculated from hot spring water chemistry (R2 = 0.72 for the O2/H2O redox couple). A separate thermodynamic analysis of bacteriohopanepolyol lipids found that predicted equilibrium abundances of observed polar headgroup distributions were also highly correlated with Eh of the surrounding water (R2= 0.84). These results represent the first quantitative thermodynamic assessment of microbial lipid adaptation in natural systems and suggest that observed lipid distributions represent energetically cost-effective assemblages along temperature and chemical gradients.
ContributorsBoyer, Grayson Maxwell (Author) / Shock, Everett (Thesis advisor) / Hartnett, Hilairy (Committee member) / Herckes, Pierre (Committee member) / Arizona State University (Publisher)
Created2018
Description
Microfluidic systems have gained popularity in the last two decades for their potential applications in manipulating micro- and nano- particulates of interest. Several different microfluidics devices have been built capable of rapidly probing, sorting, and trapping analytes of interest. Microfluidics can be combined with separation science to address challenges of obtaining a concentrated and pure distinct analyte from mixtures of increasingly similar entities. Many of these techniques have been developed to assess biological analytes of interest; one of which is dielectrophoresis (DEP), a force which acts on polarizable analytes in the presence of a non-uniform electric fields. This method can achieve high resolution separations with the unique attribute of concentrating, rather than diluting, analytes upon separation. Studies utilizing DEP have manipulated a wide range of analytes including various cell types, proteins, DNA, and viruses. These analytes range from approximately 50 nm to 1 µm in size. Many of the currently-utilized techniques for assessing these analytes are time intensive, cost prohibitive, and require specialized equipment and technical skills.
The work presented in this dissertation focuses on developing and utilizing insulator-based dielectrophoresis (iDEP) to probe a wide range of analytes; where the intrinsic properties of an analyte will determine its behavior in a microchannel. This is based on the analyte’s interactions with the electrokinetic and dielectrophoretic forces present. Novel applications of this technique to probe the biophysical difference(s) between serovars of the foodborne pathogen, Listeria monocytogenes, and surface modified Escherichia coli, are investigated. Both of these applications demonstrate the capabilities of iDEP to achieve high resolution separations and probe slight changes in the biophysical properties of an analyte of interest. To improve upon existing iDEP strategies a novel insulator design which streamlines analytes in an iDEP device while still achieving the desirable forces for separation is developed, fabricated, and tested. Finally, pioneering work to develop an iDEP device capable of manipulating larger analytes, which range in size 10-250 µm, is presented.
The work presented in this dissertation focuses on developing and utilizing insulator-based dielectrophoresis (iDEP) to probe a wide range of analytes; where the intrinsic properties of an analyte will determine its behavior in a microchannel. This is based on the analyte’s interactions with the electrokinetic and dielectrophoretic forces present. Novel applications of this technique to probe the biophysical difference(s) between serovars of the foodborne pathogen, Listeria monocytogenes, and surface modified Escherichia coli, are investigated. Both of these applications demonstrate the capabilities of iDEP to achieve high resolution separations and probe slight changes in the biophysical properties of an analyte of interest. To improve upon existing iDEP strategies a novel insulator design which streamlines analytes in an iDEP device while still achieving the desirable forces for separation is developed, fabricated, and tested. Finally, pioneering work to develop an iDEP device capable of manipulating larger analytes, which range in size 10-250 µm, is presented.
ContributorsCrowther, Claire Victoria (Author) / Hayes, Mark A. (Thesis advisor) / Gile, Gillian H (Committee member) / Ros, Alexandra (Committee member) / Herckes, Pierre (Committee member) / Arizona State University (Publisher)
Created2018
Description
Biological fluids contain information-rich mixtures of biochemicals and particles such as cells, proteins, and viruses. Selective and sensitive analysis of these fluids can enable clinicians to accurately diagnose a wide range of pathologies. Fluid samples such as these present an intriguing challenge to researchers; they are packed with potentially vital information, but notoriously difficult to analyze. Rapid and inexpensive analysis of blood and other bodily fluids is a topic gaining substantial attention in both science and medicine. Current limitations to many analyses include long culture times, expensive reagents, and the need for specialized laboratory facilities and personnel. Improving these tests and overcoming their limitations would allow faster and more widespread testing for disease and pathogens, potentially providing a significant advantage for healthcare in many settings.
Both gradient separation techniques and dielectrophoresis can solve some of the difficulties presented by complex biological samples, thanks to selective capture, isolation, and concentration of analytes. By merging dielectrophoresis with a gradient separation-based approach, gradient insulator dielectrophoresis (g-iDEP) promises benefits in the form of rapid and specific separation of extremely similar bioparticles. High-resolution capture can be achieved by exploiting variations in the characteristic physical properties of cells and other bioparticles.
Novel implementation and application of the technique has demonstrated the isolation and concentration of blood cells from a complex biological sample, differentiation of bacterial strains within a single species, and separation of antibiotic-resistant and antibiotic-susceptible bacteria. Furthermore, this approach allows simultaneous concentration of analyte, facilitating detection and downstream analysis. A theoretical description of the resolving capabilities of g-iDEP was also developed. This theory explores the relationship between experimental parameters and resolution. Results indicate the possibility of differentiating particles with dielectrophoretic mobilities that differ by as little as one part in 100,000,000, or electrophoretic mobilities differing by as little as one part in 100,000. These results indicate the potential g-iDEP holds in terms of both separatory power and the possibility for diagnostic applications.
Both gradient separation techniques and dielectrophoresis can solve some of the difficulties presented by complex biological samples, thanks to selective capture, isolation, and concentration of analytes. By merging dielectrophoresis with a gradient separation-based approach, gradient insulator dielectrophoresis (g-iDEP) promises benefits in the form of rapid and specific separation of extremely similar bioparticles. High-resolution capture can be achieved by exploiting variations in the characteristic physical properties of cells and other bioparticles.
Novel implementation and application of the technique has demonstrated the isolation and concentration of blood cells from a complex biological sample, differentiation of bacterial strains within a single species, and separation of antibiotic-resistant and antibiotic-susceptible bacteria. Furthermore, this approach allows simultaneous concentration of analyte, facilitating detection and downstream analysis. A theoretical description of the resolving capabilities of g-iDEP was also developed. This theory explores the relationship between experimental parameters and resolution. Results indicate the possibility of differentiating particles with dielectrophoretic mobilities that differ by as little as one part in 100,000,000, or electrophoretic mobilities differing by as little as one part in 100,000. These results indicate the potential g-iDEP holds in terms of both separatory power and the possibility for diagnostic applications.
ContributorsJones, Paul Vernon (Author) / Hayes, Mark (Thesis advisor) / Ros, Alexandra (Committee member) / Herckes, Pierre (Committee member) / Arizona State University (Publisher)
Created2015
Description
To investigate the impacts of an energy efficiency retrofit, indoor air quality and resident health were evaluated at a low‐income senior housing apartment complex in Phoenix, Arizona, before and after a green energy building renovation. Indoor and outdoor air quality sampling was carried out simultaneously with a questionnaire to characterize personal habits and general health of residents. Measured indoor formaldehyde levels before the building retrofit routinely exceeded reference exposure limits, but in the long‐term follow‐up sampling, indoor formaldehyde decreased for the entire study population by a statistically significant margin. Indoor PM levels were dominated by fine particles and showed a statistically significant decrease in the long‐term follow‐up sampling within certain resident subpopulations (i.e. residents who report smoking and residents who had lived longer at the apartment complex).
ContributorsFrey, S.E. (Author) / Destaillats, H. (Author) / Cohn, S. (Author) / Ahrentzen, S. (Author) / Fraser, M.P. (Author)
Created2015
Description
Quantifying halogen presence and speciation in particulate matter is crucial given the role atmospheric particulates play in transport and cycling. While some halogens (fluorine and chlorine) are often included in aerosol studies, iodine and bromine have rarely been examined, especially outside of a marine environment. Focus on this environment is, in part, due to the existence of biogenic marine sources for both halogens. However, examining iodine and bromine in an urban environment has the potential to provide key insights into the transport and processing of these species in the atmosphere. As Tempe is set within a desert environment, bromine concentration is expected to be relatively high due to its presence in Earth’s crust, while iodine is expected to exist in higher concentrations near the coast. To detect presence and concentration, ICP-MS analysis was performed on samples taken in Tempe, AZ as well as sites in Bakersfield, CA and Davis, CA, which yielded preliminary results in line with these expectations. A secondary set of samples were taken in Tempe, AZ during dust storms, haboobs, and winter holidays. CIC was used to determine the organic fraction. In doing so, this study aims to identify species present in an urban environment as well as potential transportation pathways.
ContributorsLoera, Lourdes (Author) / Herckes, Pierre (Thesis director) / Richert, Ranko (Committee member) / Fraser, Matthew (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor) / School of Human Evolution & Social Change (Contributor)
Created2023-05
Description
Atmospheric particulate matter (PM) has a pronounced effect on our climate, and exposure to PM causes negative health outcomes and elevated mortality rates in urban populations. Reactions that occur in fog can form new secondary organic aerosol material from gas-phase species or primary organic aerosols. It is important to understand these reactions, as well as how organic material is scavenged and deposited, so that climate and health effects can be fully assessed. Stable carbon isotopes have been used widely in studying gas- and particle-phase atmospheric chemistry. However, the processing of organic matter by fog has not yet been studied, even though stable isotopes can be used to track all aspects of atmospheric processing, from particle formation, particle scavenging, reactions that form secondary organic aerosol material, and particle deposition. Here, carbon isotope analysis is used for the first time to assess the processing of carbonaceous particles by fog.
This work first compares carbon isotope measurements (δ13C) of particulate matter and fog from locations across the globe to assess how different primary aerosol sources are reflected in the atmosphere. Three field campaigns are then discussed that highlight different aspects of PM formation, composition, and processing. In Tempe, AZ, seasonal and size-dependent differences in the δ13C of total carbon and n-alkanes in PM were studied. δ13C was influenced by seasonal trends, including inversion, transport, population density, and photochemical activity. Variations in δ13C among particle size fractions were caused by sources that generate particles in different size modes.
An analysis of PM from urban and suburban sites in northeastern France shows how both fog and rain can cause measurable changes in the δ13C of PM. The δ13C of PM was consistent over time when no weather events occurred, but particles were isotopically depleted by up to 1.1‰ in the presence of fog due to preferential scavenging of larger isotopically enriched particles. Finally, the δ13C of the dissolved organic carbon in fog collected on the coast of Southern California is discussed. Here, temporal depletion of the δ13C of fog by up to 1.2‰ demonstrates its use in observing the scavenging and deposition of organic PM.
This work first compares carbon isotope measurements (δ13C) of particulate matter and fog from locations across the globe to assess how different primary aerosol sources are reflected in the atmosphere. Three field campaigns are then discussed that highlight different aspects of PM formation, composition, and processing. In Tempe, AZ, seasonal and size-dependent differences in the δ13C of total carbon and n-alkanes in PM were studied. δ13C was influenced by seasonal trends, including inversion, transport, population density, and photochemical activity. Variations in δ13C among particle size fractions were caused by sources that generate particles in different size modes.
An analysis of PM from urban and suburban sites in northeastern France shows how both fog and rain can cause measurable changes in the δ13C of PM. The δ13C of PM was consistent over time when no weather events occurred, but particles were isotopically depleted by up to 1.1‰ in the presence of fog due to preferential scavenging of larger isotopically enriched particles. Finally, the δ13C of the dissolved organic carbon in fog collected on the coast of Southern California is discussed. Here, temporal depletion of the δ13C of fog by up to 1.2‰ demonstrates its use in observing the scavenging and deposition of organic PM.
ContributorsNapolitano, Denise (Author) / Herckes, Pierre (Thesis advisor) / Fraser, Matthew (Committee member) / Shock, Everett (Committee member) / Arizona State University (Publisher)
Created2018
Description
-Please adjust the format of the abstract. m-3 should be typed as "m to the minus 3" with the "minus 3" in superscript
-see the additional "abstract.pdf" document for formatting
In arid environments like Phoenix, many professional and residential outdoor spaces are cooled by the use of misting systems. These systems spray a fine mist of water droplets that cool down the surrounding air through the endothermic evaporation process. When the water droplets evaporate, they leave behind dissolved material that is present in the water, generating ambient particulate matter (PM). Thus, misting systems are a point source of PM. Currently there is no information on their impact on air quality in close proximity to these systems, or on the chemical composition of the particulate matter generated by the evaporating mist.
In this project, PM concentrations are found to increase on average by a factor of 8 from ambient levels in the vicinity of a residential misting system in controlled experiments. PM concentrations in public places that use misting systems are also investigated. The PM10 concentrations in public places ranged from 0.102 ± 0.010 mg m-3 to 1.47 ± 0.15 mg m-3, and PM2.5 ranged from 0.095 ± 0.010 mg m-3 to 0.99 ± 0.10 mg m-3. Air quality index (AQI) values based on these concentrations indicate that these levels of PM range from unhealthy to hazardous in most cases. PM concentrations tend to decrease after remaining relatively constant with increasing distance from misting systems. Chemical data reveal that chloride and magnesium ions may be used as tracers of aerosolized water from misting systems. The average chloride concentration was 71 µg m-3 in misting samples and below the detection limit for Cl- (< 8.2 µg m-3) in ambient samples. The average magnesium concentration was 11.7 µg m-3 in misting samples and 0.23 µg m-3 in ambient samples.
-see the additional "abstract.pdf" document for formatting
In arid environments like Phoenix, many professional and residential outdoor spaces are cooled by the use of misting systems. These systems spray a fine mist of water droplets that cool down the surrounding air through the endothermic evaporation process. When the water droplets evaporate, they leave behind dissolved material that is present in the water, generating ambient particulate matter (PM). Thus, misting systems are a point source of PM. Currently there is no information on their impact on air quality in close proximity to these systems, or on the chemical composition of the particulate matter generated by the evaporating mist.
In this project, PM concentrations are found to increase on average by a factor of 8 from ambient levels in the vicinity of a residential misting system in controlled experiments. PM concentrations in public places that use misting systems are also investigated. The PM10 concentrations in public places ranged from 0.102 ± 0.010 mg m-3 to 1.47 ± 0.15 mg m-3, and PM2.5 ranged from 0.095 ± 0.010 mg m-3 to 0.99 ± 0.10 mg m-3. Air quality index (AQI) values based on these concentrations indicate that these levels of PM range from unhealthy to hazardous in most cases. PM concentrations tend to decrease after remaining relatively constant with increasing distance from misting systems. Chemical data reveal that chloride and magnesium ions may be used as tracers of aerosolized water from misting systems. The average chloride concentration was 71 µg m-3 in misting samples and below the detection limit for Cl- (< 8.2 µg m-3) in ambient samples. The average magnesium concentration was 11.7 µg m-3 in misting samples and 0.23 µg m-3 in ambient samples.
ContributorsKnight, William Louis (Co-author) / Knight, William (Co-author) / Herckes, Pierre (Thesis director) / Fraser, Matthew (Committee member) / Hamilton, Kerry (Committee member) / School of Sustainability (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Particulate matter (PM) air pollution is a known factor to exacerbate cardiopulmonary diseases. We previously demonstrated that PM mediated endothelial injury and barrier disruption via modulation of the endothelial cytoskeleton and cell-cell junctions, while the effects of PM exposure on cell-cell communication and gap junction activity are still unknown. This study is focused on the characterization of PM-mediated endothelial dysfunction via Connexin 43 (Cx43), the most abundant Gap junction protein expressed in lung endothelial cells (ECs). PM exposure induces a time-dependent elevation of Cx43 in human lung ECs, at both mRNA and protein levels. N-acetyl-cysteine (NAC), an ROS scavenger, significantly suppresses PM-induced Cx43 expression. Membrane-associated and ER/ Golgi apparatus Cx43 protein are elevated upon PM challenge. In addition, PM also activates the gap junction activity, indicated by the transportation of green fluorescence dye between two adjacent ECs. Moreover, GAP27, a selective Cx43 channel inhibitor, attenuates PM-reduced human lung EC barrier disruption, measured by trans-endothelial electrical resistance (TER) with an electric cell-substrate impedance sensing system. Moreover, knock-down the expression of Cx43 by its selective siRNA alleviates PM-induced MLC phosphorylation. These results highly suggest that Cx43 plays a key role in PM-mediated endothelial barrier disruption and signal transduction. Cx43 may deputy as a therapeutic target in PM-mediated cardiopulmonary disorders.
ContributorsKheshtchin-Kamel, Nabia (Author) / Welcome, Natalie (Thesis director) / Wang, Ting (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12