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- Creators: Debussy, Claude, 1862-1918
- Status: Published
Description
Microbially induced calcium carbonate precipitation (MICP) is attracting increasing attention as a sustainable means of soil improvement. While there are several possible MICP mechanisms, microbial denitrification has the potential to become one of the preferred methods for MICP because complete denitrification does not produce toxic byproducts, readily occurs under anoxic conditions, and potentially has a greater carbonate yield per mole of organic electron donor than other MICP processes. Denitrification may be preferable to ureolytic hydrolysis, the MICP process explored most extensively to date, as the byproduct of denitrification is benign nitrogen gas, while the chemical pathways involved in hydrolytic ureolysis processes produce undesirable and potentially toxic byproducts such as ammonium (NH4+). This thesis focuses on bacterial denitrification and presents preliminary results of bench-scale laboratory experiments on denitrification as a candidate calcium carbonate precipitation mechanism. The bench-scale bioreactor and column tests, conducted using the facultative anaerobic bacterium Pseudomonas denitrificans, show that calcite can be precipitated from calcium-rich pore water using denitrification. Experiments also explore the potential for reducing environmental impacts and lowering costs associated with denitrification by reducing the total dissolved solids in the reactors and columns, optimizing the chemical matrix, and addressing the loss of free calcium in the form of calcium phosphate precipitate from the pore fluid. The potential for using MICP to sequester radionuclides and metal contaminants that are migrating in groundwater is also investigated. In the sequestration process, divalent cations and radionuclides are incorporated into the calcite structure via substitution, forming low-strontium calcium carbonate minerals that resist dissolution at a level similar to that of calcite. Work by others using the bacterium Sporosarcina pasteurii has suggested that in-situ sequestration of radionuclides and metal contaminants can be achieved through MICP via hydrolytic ureolysis. MICP through bacterial denitrification seems particularly promising as a means for sequestering radionuclides and metal contaminants in anoxic environments due to the anaerobic nature of the process and the ubiquity of denitrifying bacteria in the subsurface.
ContributorsHamdan, Nasser (Author) / Kavazanjian, Edward (Thesis advisor) / Rittmann, Bruce E. (Thesis advisor) / Shock, Everett (Committee member) / Arizona State University (Publisher)
Created2013
Description
This dissertation is presented in two sections. First, I explore two methods of using stable isotope analysis to trace environmental and biogeochemical processes. Second, I present two related studies investigating student understanding of the biogeochemical concepts that underlie part one. Fe and Hg are each biogeochemically important elements in their own way. Fe is a critical nutrient for phytoplankton, while Hg is detrimental to nearly all forms of life. Fe is often a limiting factor in marine phytoplankton growth. The largest source, by mass, of Fe to the open ocean is windblown mineral dust, but other more soluble sources are more bioavailable. To look for evidence of these non-soil dust sources of Fe to the open ocean, I measured the isotopic composition of aerosol samples collected on Bermuda. I found clear evidence in the fine size fraction of a non-soil dust Fe source, which I conclude is most likely from biomass burning. Widespread adoption of compact fluorescent lamps (CFL) has increased their importance as a source of environmental Hg. Isotope analysis would be a useful tool in quantifying this impact if the isotopic composition of Hg from CFL were known. My measurements show that CFL-Hg is isotopically fractionated, in a unique pattern, during normal operation. This fractionation is large and has a distinctive, mass-independent signature, such that CFL Hg can be uniquely identified from other sources. Misconceptions research in geology has been a very active area of research, but student thinking regarding the related field of biogeochemistry has not yet been studied in detail. From interviews with 40 undergraduates, I identified over 150 specific misconceptions. I also designed a multiple-choice survey (concept inventory) to measure understanding of these same biogeochemistry concepts. I present statistical evidence, based on the Rasch model, for the reliability and validity of this instrument. This instrument will allow teachers and researchers to easily quantify learning outcomes in biogeochemistry and will complement existing concept inventories in geology, chemistry, and biology.
ContributorsMead, Chris (Author) / Anbar, Ariel (Thesis advisor) / Semken, Steven (Committee member) / Shock, Everett (Committee member) / Herckes, Pierre (Committee member) / Hartnett, Hilairy (Committee member) / Arizona State University (Publisher)
Created2014
Description
Stable isotopes were measured in the groundwaters of the Salt River Valley basin in central Arizona to explore the utility of stable isotopes for sourcing recharge waters and engineering better well designs. Delta values for the sampled groundwaters range from -7.6‰ to -10‰ in 18O and -60‰ to -91‰ in D and display displacements off the global meteoric water line indicative of surficial evaporation during river transport into the area. Groundwater in the basin is all derived from top-down river recharge; there is no evidence of ancient playa waters even in the playa deposits. The Salt and Verde Rivers are the dominant source of groundwater for the East Salt River valley- the Agua Fria River also contributes significantly to the West Salt River Valley. Groundwater isotopic compositions are generally more depleted in 18O and D with depth, indicating past recharge in cooler climates, and vary within subsurface aquifer layers as sampled during well drilling. When isotopic data were evaluated together with geologic and chemical analyses and compared with data from the final well production water it was often possible to identify: 1) which horizons are the primary producers of groundwater flow and how that might change with time, 2) the chemical exchange of cations and anions via water-rock interaction during top-down mixing of recharge water with older waters, 3) how much well production might be lost if arsenic-contributing horizons were sealed off, and 4) the extent to which replacement wells tap different subsurface water sources. In addition to identifying sources of recharge, stable isotopes offer a new and powerful approach for engineering better and more productive water wells.
ContributorsBond, Angela Nicole (Author) / Knauth, Paul (Thesis advisor) / Hartnett, Hilairy (Committee member) / Shock, Everett (Committee member) / Arizona State University (Publisher)
Created2010
Description
Contaminants of emerging concern (CECs) present in wastewater effluent can threat its safe discharge or reuse. Additional barriers of protection can be provided using advanced or natural treatment processes. This dissertation evaluated ozonation and constructed wetlands to remove CECs from wastewater effluent. Organic CECs can be removed by hydroxyl radical formed during ozonation, however estimating the ozone demand of wastewater effluent is complicated due to the presence of reduced inorganic species. A method was developed to estimate ozone consumption only by dissolved organic compounds and predict trace organic oxidation across multiple wastewater sources. Organic and engineered nanomaterial (ENM) CEC removal in constructed wetlands was investigated using batch experiments and continuous-flow microcosms containing decaying wetland plants. CEC removal varied depending on their physico-chemical properties, hydraulic residence time (HRT) and relative quantities of plant materials in the microcosms. At comparable HRTs, ENM removal improved with higher quantity of plant materials due to enhanced sorption which was verified in batch-scale studies with plant materials. A fate-predictive model was developed to evaluate the role of design loading rates on organic CEC removal. Areal removal rates increased with hydraulic loading rates (HLRs) and carbon loading rates (CLRs) unless photolysis was the dominant removal mechanism (e.g. atrazine). To optimize CEC removal, wetlands with different CLRs can be used in combination without lowering the net HLR. Organic CEC removal in denitrifying conditions of constructed wetlands was investigated and selected CECs (e.g. estradiol) were found to biotransform while denitrification occurred. Although level of denitrification was affected by HRT, similar impact on estradiol was not observed due to a dominant effect from plant biomass quantity. Overall, both modeling and experimental findings suggest considering CLR as an equally important factor with HRT or HLR to design constructed wetlands for CEC removal. This dissertation provided directions to select design parameters for ozonation (ozone dose) and constructed wetlands (design loading rates) to meet organic CEC removal goals. Future research is needed to understand fate of ENMs during ozonation and quantify the contributions from different transformation mechanisms occurring in the wetlands to incorporate in a model and evaluate the effect of wetland design.
ContributorsSharif, Fariya (Author) / Westerhoff, Paul (Thesis advisor) / Halden, Rolf (Committee member) / Fox, Peter (Committee member) / Herckes, Pierre (Committee member) / Arizona State University (Publisher)
Created2013
Description
Black carbon (BC) is the product of incomplete combustion of biomass and fossil fuels. It is found ubiquitously in nature and is relevant to studies in atmospheric science, soil science, oceanography, and anthropology. Black carbon is best described using a combustion continuum that sub-classifies BC into slightly charred biomass, char, charcoal and soot. These sub-classifications range in particle size, formation temperature, and relative reactivity. Interest in BC has increased because of its role in the long-term storage of organic matter and the biogeochemistry of urban areas. The global BC budget is unbalanced. Production of BC greatly outweighs decomposition of BC. This suggests that there are unknown or underestimated BC removal processes, and it is likely that some of these processes are occurring in soils. However, little is known about BC reactivity in soil and especially in desert soil. This work focuses on soot BC, which is formed at higher temperatures and has a lower relative reactivity than other forms of BC. Here, I assess the contribution of soot BC to central AZ soils and use the isotopic composition of soot BC to identify sources of soot BC. Soot BC is a significant (31%) fraction of the soil organic matter in central AZ and this work suggests that desert and urban soils may be a storage reservoir for soot BC. I further identify previously unknown removal processes of soot BC found naturally in soil and demonstrate that soil soot BC undergoes abiotic (photo-oxidation) and biotic reactions. Not only is soot BC degraded by these processes, but its chemical composition is altered, suggesting that soot BC contains some chemical moieties that are more reactive than others. Because soot BC demonstrates both refractory and reactive character, it is likely that the structure of soot BC; therefore, its interactions in the environment are complex and it is not simply a recalcitrant material.
ContributorsHamilton, George (Author) / Hartnett, Hilairy E (Thesis advisor) / Herckes, Pierre (Committee member) / Hall, Sharon (Committee member) / Arizona State University (Publisher)
Created2013
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
In enzyme induced carbonate precipitation (EICP), calcium carbonate (CaCO3) precipitation is catalyzed by plant-derived urease enzyme. In EICP, urea hydrolyzes into ammonia and inorganic carbon, altering geochemical conditions in a manner that promotes carbonate mineral precipitation. The calcium source in this process comes from calcium chloride (CaCl2) in aqueous solution. Research work conducted for this dissertation has demonstrated that EICP can be employed for a variety of geotechnical purposes, including mass soil stabilization, columnar soil stabilization, and stabilization of erodible surficial soils. The research presented herein also shows that the optimal ratio of urea to CaCl2 at ionic strengths of less than 1 molar is approximately 1.75:1. EICP solutions of very high initial ionic strength (i.e. 6 M) as well as high urea concentrations (> 2 M) resulted in enzyme precipitation (salting-out) which hindered carbonate precipitation. In addition, the production of NH4+ may also result in enzyme precipitation. However, enzyme precipitation appeared to be reversible to some extent. Mass soil stabilization was demonstrated via percolation and mix-and-compact methods using coarse silica sand (Ottawa 20-30) and medium-fine silica sand (F-60) to produce cemented soil specimens whose strength improvement correlated with CaCO3 content, independent of the method employed to prepare the specimen. Columnar stabilization, i.e. creating columns of soil cemented by carbonate precipitation, using Ottawa 20-30, F-60, and native AZ soil was demonstrated at several scales beginning with small columns (102-mm diameter) and culminating in a 1-m3 soil-filled box. Wind tunnel tests demonstrated that surficial soil stabilization equivalent to that provided by thoroughly wetting the soil can be achieved through a topically-applied solution of CaCl2, urea, and the urease enzyme. The topically applied solution was shown to form an erosion-resistant CaCO3 crust on fine sand and silty soils. Cementation of erodible surficial soils was also achieved via EICP by including a biodegradable hydrogel in the stabilization solution. A dilute hydrogel solution extended the time frame over which the precipitation reaction could occur and provided improved spatial control of the EICP solution.
ContributorsHamdan, Nasser M (Author) / Kavazanjian Jr., Edward (Thesis advisor) / Rittmann, Bruce (Thesis advisor) / Shock, Everett (Committee member) / Arizona State University (Publisher)
Created2015
Description
Geopolymers, a class of X-ray amorphous, ceramic-like aluminosilicate materials are produced at ambient temperatures through a process called geopolymerization. Due to both low energy requirement during synthesis and interesting mechanical and chemical properties, geopolymers are grabbing enormous attention. Although geopolymers have a broad range of applications including thermal/acoustic insulation and waste immobilization, they are always prepared in monolithic form. The primary aim of this study is to produce new nanostructured materials from the geopolymerization process, including porous monoliths and powders.
In view of the current interest in porous geopolymers for non-traditional applications, it is becoming increasingly important to develop synthetic techniques to introduce interconnected pores into the geopolymers. This study presents a simple synthetic route to produce hierarchically porous geopolymers via a reactive emulsion templating process utilizing triglyceride oil. In this new method, highly alkaline geopolymer resin is mixed with canola oil to form a homogeneous viscous emulsion which, when cured at 60 °C, gives a hard monolithic material. During the process, the oil in the alkaline emulsion undergoes a saponification reaction to decompose into water-soluble soap and glycerol molecules which are extracted to yield porous geopolymers. Nitrogen sorption studies indicates the presence of mesopores, whereas the SEM studies reveals that the mesoporous geopolymer matrix is dotted with spherical macropores. The method exhibits flexibility in that the pore structure of the final porous geopolymers products can be adjusted by varying the precursor composition.
In a second method, the geopolymerization process is modified to produce highly dispersible geopolymer particles, by activating metakaolin with sodium silicate solutions containing excess alkali, and curing for short duration under moist conditions. The produced geopolymer particles exhibit morphology similar to carbon blacks and structured silicas, while also being stable over a wide pH range.
Finally, highly crystalline hierarchical faujasite zeolites are prepared by yet another modification of the geopolymerization process. In this technique, the second method is combined with a saponification reaction of triglyceride oil. The resulting hierarchical zeolites exhibit superior CO2-sorption properties compared to equivalent commercially available and currently reported materials. Additionally, the simplicity of all three of these techniques means they are readily scalable.
In view of the current interest in porous geopolymers for non-traditional applications, it is becoming increasingly important to develop synthetic techniques to introduce interconnected pores into the geopolymers. This study presents a simple synthetic route to produce hierarchically porous geopolymers via a reactive emulsion templating process utilizing triglyceride oil. In this new method, highly alkaline geopolymer resin is mixed with canola oil to form a homogeneous viscous emulsion which, when cured at 60 °C, gives a hard monolithic material. During the process, the oil in the alkaline emulsion undergoes a saponification reaction to decompose into water-soluble soap and glycerol molecules which are extracted to yield porous geopolymers. Nitrogen sorption studies indicates the presence of mesopores, whereas the SEM studies reveals that the mesoporous geopolymer matrix is dotted with spherical macropores. The method exhibits flexibility in that the pore structure of the final porous geopolymers products can be adjusted by varying the precursor composition.
In a second method, the geopolymerization process is modified to produce highly dispersible geopolymer particles, by activating metakaolin with sodium silicate solutions containing excess alkali, and curing for short duration under moist conditions. The produced geopolymer particles exhibit morphology similar to carbon blacks and structured silicas, while also being stable over a wide pH range.
Finally, highly crystalline hierarchical faujasite zeolites are prepared by yet another modification of the geopolymerization process. In this technique, the second method is combined with a saponification reaction of triglyceride oil. The resulting hierarchical zeolites exhibit superior CO2-sorption properties compared to equivalent commercially available and currently reported materials. Additionally, the simplicity of all three of these techniques means they are readily scalable.
ContributorsMedpelli, Dinesh (Author) / Seo, Dong-Kyun (Thesis advisor) / Herckes, Pierre (Committee member) / Petuskey, William (Committee member) / Arizona State University (Publisher)
Created2015
Description
The focus of this thesis is to study dissolved organic carbon composition and reactivity along the Colorado and Green Rivers. Dissolved organic carbon (DOC) in large-scale, managed rivers is relatively poorly studied as most literature has focused on pristine unmanaged rivers. The Colorado River System is the 7th largest in the North America; there are seventeen large dams along the Colorado and Green River. DOC in rivers and in the lakes formed by dams (reservoirs) undergo photo-chemical and bio-degradation. DOC concentration and composition in these systems were investigated using bulk concentration, optical properties, and fluorescence spectroscopy. The riverine DOC concentration decreased from upstream to downstream but there was no change in the specific ultraviolet absorbance at 254 nm (SUVA254). Total fluorescence also decreased along the river. In general, the fluorescence index (FI) increased slightly, the humification index (HIX) decreased, and the freshness index (β/α) increased from upstream to downstream. Photo-oxidation and biodegradation experiments were used to determine if the observed changes in DOC composition along the river could be driven by these biogeochemical alteration processes.
In two-week natural sunlight photo-oxidation experiments the DOC concentration did not change, while the SUVA254 and TF decreased. In addition, the FI and ‘freshness’ increased and HIX decreased during photo-oxidation. Photo-oxidation can explain the upstream to downstream trends for TF, FI, HIX, and freshness observed in river water. Serial photo-oxidation and biodegradation experiments were performed on water collected from three sites along the Colorado River. Bulk DOC concentration in all samples decreased during the biodegradation portion of the study, but DOC bioavailability was lower in samples that were photo-oxidized prior to the bioavailability study.
The upstream to downstream trends in DOC concentration and composition along the river can be explained by a combination of photo-chemical and microbial degradation. The bulk DOC concentration change is primarily driven by microbial degradation, while the changes in the composition of the fluorescent DOC are driven by photo-oxidation.
In two-week natural sunlight photo-oxidation experiments the DOC concentration did not change, while the SUVA254 and TF decreased. In addition, the FI and ‘freshness’ increased and HIX decreased during photo-oxidation. Photo-oxidation can explain the upstream to downstream trends for TF, FI, HIX, and freshness observed in river water. Serial photo-oxidation and biodegradation experiments were performed on water collected from three sites along the Colorado River. Bulk DOC concentration in all samples decreased during the biodegradation portion of the study, but DOC bioavailability was lower in samples that were photo-oxidized prior to the bioavailability study.
The upstream to downstream trends in DOC concentration and composition along the river can be explained by a combination of photo-chemical and microbial degradation. The bulk DOC concentration change is primarily driven by microbial degradation, while the changes in the composition of the fluorescent DOC are driven by photo-oxidation.
ContributorsBowman, Margaret (Author) / Hartnett, Hilairy E (Thesis advisor) / Hayes, Mark A. (Committee member) / Herckes, Pierre (Committee member) / Arizona State University (Publisher)
Created2015
Description
The taxonomic and metabolic profile of the microbial community inhabiting a natural system is largely determined by the physical and geochemical properties of the system. However, the influences of parameters beyond temperature, pH and salinity have been poorly analyzed with few studies incorporating the comprehensive suite of physical and geochemical measurements required to fully investigate the complex interactions known to exist between biology and the environment. Further, the techniques used to classify the taxonomic and functional composition of a microbial community are fragmented and unwieldy, resulting in unnecessarily complex and often non-consilient results.
This dissertation integrates environmental metagenomes with extensive geochemical metadata for the development and application of multidimensional biogeochemical metrics. Analysis techniques including a Markov cluster-based evolutionary distance between whole communities, oligonucleotide signature-based taxonomic binning and principal component analysis of geochemical parameters allow for the determination of correlations between microbial community dynamics and environmental parameters. Together, these techniques allow for the taxonomic classification and functional analysis of the evolution of hot spring communities. Further, these techniques provide insight into specific geochemistry-biology interactions which enable targeted analyses of community taxonomic and functional diversity. Finally, analysis of synonymous substitution rates among physically separated microbial communities provides insights into microbial dispersion patterns and the roles of environmental geochemistry and community metabolism on DNA transfer among hot spring communities.
The data presented here confirms temperature and pH as the primary factors shaping the evolutionary trajectories of microbial communities. However, the integration of extensive geochemical metadata reveals new links between geochemical parameters and the distribution and functional diversification of communities. Further, an overall geochemical gradient (from multivariate analyses) between natural systems provides one of the most complete predictions of microbial community functional composition and inter-community DNA transfer rates. Finally, the taxonomic classification and clustering techniques developed within this dissertation will facilitate future genomic and metagenomic studies through enhanced community profiling obtainable via Markov clustering, longer oligonucleotide signatures and insight into PCR primer biases.
This dissertation integrates environmental metagenomes with extensive geochemical metadata for the development and application of multidimensional biogeochemical metrics. Analysis techniques including a Markov cluster-based evolutionary distance between whole communities, oligonucleotide signature-based taxonomic binning and principal component analysis of geochemical parameters allow for the determination of correlations between microbial community dynamics and environmental parameters. Together, these techniques allow for the taxonomic classification and functional analysis of the evolution of hot spring communities. Further, these techniques provide insight into specific geochemistry-biology interactions which enable targeted analyses of community taxonomic and functional diversity. Finally, analysis of synonymous substitution rates among physically separated microbial communities provides insights into microbial dispersion patterns and the roles of environmental geochemistry and community metabolism on DNA transfer among hot spring communities.
The data presented here confirms temperature and pH as the primary factors shaping the evolutionary trajectories of microbial communities. However, the integration of extensive geochemical metadata reveals new links between geochemical parameters and the distribution and functional diversification of communities. Further, an overall geochemical gradient (from multivariate analyses) between natural systems provides one of the most complete predictions of microbial community functional composition and inter-community DNA transfer rates. Finally, the taxonomic classification and clustering techniques developed within this dissertation will facilitate future genomic and metagenomic studies through enhanced community profiling obtainable via Markov clustering, longer oligonucleotide signatures and insight into PCR primer biases.
ContributorsAlsop, Eric Bennie (Author) / Raymond, Jason (Thesis advisor) / Anbar, Ariel (Committee member) / Farmer, Jack (Committee member) / Shock, Everett (Committee member) / Walker, Sarah (Committee member) / Arizona State University (Publisher)
Created2014