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For decades, understanding the complexity of behaviors, motivations, and values has interested researchers across various disciplines. So much so that there are numerous terms, frameworks, theories, and studies devoted to understanding these complexities and how they interact and evolve into actions. However, little research has examined how employee behaviors translate

For decades, understanding the complexity of behaviors, motivations, and values has interested researchers across various disciplines. So much so that there are numerous terms, frameworks, theories, and studies devoted to understanding these complexities and how they interact and evolve into actions. However, little research has examined how employee behaviors translate into the work environment, particularly regarding perceived organizational success. This study advances research by quantitatively assessing how a greater number of individual employees’ pro-environmental behaviors are related to the perceived success of environmentally sustainable workplace activities. We have concluded that the more pro-environmental behaviors an employee embodies, the more positively they perceive the success of their local government's sustainable purchasing policy. Additionally, other factors matter, including organizational behaviors, like training, innovation, and reduction of red tape.

ContributorsFox, Angela (Author) / Darnall, Nicole (Thesis advisor) / Bretschneider, Stuart (Committee member) / Behravesh, Shirley-Ann (Committee member) / School of Sustainability (Contributor)
Created2022-04-19
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BACKGROUND: The City of Phoenix initiated the HeatReady program in 2018 to prepare for extreme heat, as there was no official tool, framework, or mechanism at the city level to manage extreme heat. The current landscape of heat safety culture in schools, which are critical community hubs, has received less

BACKGROUND: The City of Phoenix initiated the HeatReady program in 2018 to prepare for extreme heat, as there was no official tool, framework, or mechanism at the city level to manage extreme heat. The current landscape of heat safety culture in schools, which are critical community hubs, has received less illumination. HeatReady Schools—a critical component of a HeatReady City—are those that are increasingly able to identify, prepare for, mitigate, track, and respond to the negative impacts of schoolgrounds heat. However, minimal attention has been given to formalize heat preparedness in schools to mitigate high temperatures and health concerns in schoolchildren, a heat-vulnerable population. This study set out to understand heat perceptions, (re)actions, and recommendations of key stakeholders and to identify critical themes around heat readiness. METHODS: An exploratory sequential mixed-methods case study approach was used. These methods focused on acquiring new insight on heat perceptions at elementary schools through semi-structured interviews using thematic analysis and the Delphi panel. Participants included public health professionals and school community members at two elementary schools—one public charter, one public—in South Phoenix, Arizona, a region that has been burdened historically with inequitable distribution of heat resources due to environmental racism and injustices. RESULTS: Findings demonstrated that 1) current heat safety resources are available but not fully utilized within the school sites, 2) expert opinions support that extreme heat readiness plans must account for site-specific needs, particularly education as a first step, and 3) students are negatively impacted by the effects of extreme heat, whether direct or indirect, both inside and outside the classroom. CONCLUSIONS: From key informant interviews and a Delphi panel, a list of 30 final recommendations were developed as important actions to be taken to become “HeatReady.” Future work will apply these recommendations in a HeatReady School Growth Tool that schools can tailor be to their individual needs to improve heat safety and protection measures at schools.

ContributorsShortridge, Adora (Author) / Walker, William VI (Author) / White, Dave (Committee member) / Guardaro, Melissa (Committee member) / Hondula, David M. (Committee member) / Vanos, Jennifer (Committee member) / School of Sustainability (Contributor)
Created2022-04-18
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Description

Nutrient availability and ratios can play an important role in shaping microbial communities of freshwater ecosystems. The Cuatro Ciénegas Basin (CCB) in Mexico is a desert oasis where, perhaps paradoxically, high microbial diversity coincides with extreme oligotrophy. To better understand the effects of nutrients on microbial communities in CCB, a

Nutrient availability and ratios can play an important role in shaping microbial communities of freshwater ecosystems. The Cuatro Ciénegas Basin (CCB) in Mexico is a desert oasis where, perhaps paradoxically, high microbial diversity coincides with extreme oligotrophy. To better understand the effects of nutrients on microbial communities in CCB, a mesocosm experiment was implemented in a stoichiometrically imbalanced pond, Lagunita, which has an average TN:TP ratio of 122 (atomic). The experiment had four treatments, each with five spatial replicates – unamended controls and three fertilization treatments with different nitrogen:phosphorus (N:P) regimes (P only, N:P = 16 and N:P = 75 by atoms). In the water column, quantitative PCR of the 16S rRNA gene indicated that P enrichment alone favored proliferation of bacterial taxa with high rRNA gene copy number, consistent with a previously hypothesized but untested connection between rRNA gene copy number and P requirement. Bacterial and microbial eukaryotic community structure was investigated by pyrosequencing of 16S and 18S rRNA genes from the planktonic and surficial sediment samples. Nutrient enrichment shifted the composition of the planktonic community in a treatment-specific manner and promoted the growth of previously rare bacterial taxa at the expense of the more abundant, potentially endemic, taxa. The eukaryotic community was highly enriched with phototrophic populations in the fertilized treatment. The sediment microbial community exhibited high beta diversity among replicates within treatments, which obscured any changes due to fertilization. Overall, these results showed that nutrient stoichiometry can be an important factor in shaping microbial community structure.

ContributorsLee, Zarraz (Author) / Poret-Peterson, Amisha (Author) / Siefert, Janet L. (Author) / Kaul, Drishti (Author) / Moustafa, Ahmed (Author) / Allen, Andrew E. (Author) / Dupont, Chris L. (Author) / Eguiarte, Luis E. (Author) / Souza, Valeria (Author) / Elser, James (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor) / School of Earth and Space Exploration (Contributor)
Created2017-05-30
Description

Cell-sediment separation methods can potentially enable determination of the elemental composition of microbial communities by removing the sediment elemental contribution from bulk samples. We demonstrate that a separation method can be applied to determine the composition of prokaryotic cells. The method uses chemical and physical means to extract cells from

Cell-sediment separation methods can potentially enable determination of the elemental composition of microbial communities by removing the sediment elemental contribution from bulk samples. We demonstrate that a separation method can be applied to determine the composition of prokaryotic cells. The method uses chemical and physical means to extract cells from benthic sediments and mats. Recovery yields were between 5% and 40%, as determined from cell counts. The method conserves cellular element contents to within 30% or better, as assessed by comparing C, N, P, Mg, Al, Ca, Ti, Mn, Fe, Ni, Cu, Zn, and Mo contents in Escherichia coli. Contamination by C, N, and P from chemicals used during the procedure was negligible. Na and K were not conserved, being likely exchanged through the cell membrane as cations during separation. V, Cr, and Co abundances could not be determined due to large (>100%) measurement uncertainties. We applied this method to measure elemental contents in extremophilic communities of Yellowstone National Park hot springs. The method was generally successful at separating cells from sediment, but does not discriminate between cells and detrital biological or noncellular material of similar density. This resulted in Al, Ti, Mn, and Fe contamination, which can be tracked using proxies such as metal:Al ratios. With these caveats, we present the first measurements, to our knowledge, of the elemental abundances of a chemosynthetic community. The communities have C:N ratios typical of aquatic microorganisms, are low in P, and their metal abundances vary between hot springs by orders of magnitude.

ContributorsNeveu, Marc (Author) / Poret-Peterson, Amisha (Author) / Lee, Zarraz (Author) / Anbar, Ariel (Author) / Elser, James (Author) / College of Liberal Arts and Sciences (Contributor) / School of Earth and Space Exploration (Contributor) / School of Life Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-07-01
Description

ASU’s waste diversion goal is 90% by the fiscal year 2025 and will require collaboration across many departments and programs to be successful. Reducing plastic use, especially single-use plastic, is critical in reaching 90% waste diversion in the supply chain. To reduce supply chain single-use plastics, ASU will need the

ASU’s waste diversion goal is 90% by the fiscal year 2025 and will require collaboration across many departments and programs to be successful. Reducing plastic use, especially single-use plastic, is critical in reaching 90% waste diversion in the supply chain. To reduce supply chain single-use plastics, ASU will need the cooperation of suppliers on efforts like piloting plastic free packaging programs, packaging take back programs, alternative packaging opportunities, or promoting alternative products that contain little-to-no single-use plastic. Creating a proposed approach through identifying strategic external partners, a high-level approach to implementation, and obstacles will impact how future goals and policies are set. Determining impact and added value of the project will help cultivate support from leadership, internal stakeholders, and suppliers. The project focus will include multiple deliverables, but the final output will be a timeline that maps out what plastic streams to eliminate and when to help ASU reach their waste diversion goals. It begins with “low-hanging fruit” like straws and plastic bags and ends with a university free from all non-essential single-use plastic.

ContributorsHarper, Trevor (Author) / Hegde, Sakshi (Author) / McCrossan, Nico (Author) / Knaggs, Cecilia (Author) / Pyne, Chloe (Author) / School of Sustainability (Contributor)
Created2022-05
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Description

ASU’s waste diversion goal is 90% by the fiscal year 2025 and will require collaboration across many departments and programs to be successful. Reducing plastic use, especially single-use plastic, is critical in reaching 90% waste diversion in the supply chain. To reduce supply chain single-use plastics, ASU will need the

ASU’s waste diversion goal is 90% by the fiscal year 2025 and will require collaboration across many departments and programs to be successful. Reducing plastic use, especially single-use plastic, is critical in reaching 90% waste diversion in the supply chain. To reduce supply chain single-use plastics, ASU will need the cooperation of suppliers on efforts like piloting plastic free packaging programs, packaging take back programs, alternative packaging opportunities, or promoting alternative products that contain little-to-no single-use plastic. Creating a proposed approach through identifying strategic external partners, a high-level approach to implementation, and obstacles will impact how future goals and policies are set. Determining impact and added value of the project will help cultivate support from leadership, internal stakeholders, and suppliers. The project focus will include multiple deliverables, but the final output will be a timeline that maps out what plastic streams to eliminate and when to help ASU reach their waste diversion goals. It begins with “low-hanging fruit” like straws and plastic bags and ends with a university free from all non-essential single-use plastic.

ContributorsHarper, Trevor (Author) / Hegde, Sakshi (Author) / Knaggs, Cecilia (Author) / McCrossan, Nico (Author) / Pyne, Chloe (Author) / School of Sustainability (Contributor)
Created2022-05
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Description

ASU’s waste diversion goal is 90% by the fiscal year 2025 and will require collaboration across many departments and programs to be successful. Reducing plastic use, especially single-use plastic, is critical in reaching 90% waste diversion in the supply chain. To reduce supply chain single-use plastics, ASU will need the

ASU’s waste diversion goal is 90% by the fiscal year 2025 and will require collaboration across many departments and programs to be successful. Reducing plastic use, especially single-use plastic, is critical in reaching 90% waste diversion in the supply chain. To reduce supply chain single-use plastics, ASU will need the cooperation of suppliers on efforts like piloting plastic free packaging programs, packaging take back programs, alternative packaging opportunities, or promoting alternative products that contain little-to-no single-use plastic. Creating a proposed approach through identifying strategic external partners, a high-level approach to implementation, and obstacles will impact how future goals and policies are set. Determining impact and added value of the project will help cultivate support from leadership, internal stakeholders, and suppliers. The project focus will include multiple deliverables, but the final output will be a timeline that maps out what plastic streams to eliminate and when to help ASU reach their waste diversion goals. It begins with “low-hanging fruit” like straws and plastic bags and ends with a university free from all non-essential single-use plastic.

ContributorsHarper, Trevor (Author) / Hegde, Sakshi (Author) / McCrossan, Nico (Author) / Knaggs, Cecilia (Author) / Pyne, Chloe (Author) / School of Sustainability (Contributor)
Created2022-05
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Description
Open-ended evolution (OEE) is relevant to a variety of biological, artificial and technological systems, but has been challenging to reproduce in silico. Most theoretical efforts focus on key aspects of open-ended evolution as it appears in biology. We recast the problem as a more general one in dynamical systems theory,

Open-ended evolution (OEE) is relevant to a variety of biological, artificial and technological systems, but has been challenging to reproduce in silico. Most theoretical efforts focus on key aspects of open-ended evolution as it appears in biology. We recast the problem as a more general one in dynamical systems theory, providing simple criteria for open-ended evolution based on two hallmark features: unbounded evolution and innovation. We define unbounded evolution as patterns that are non-repeating within the expected Poincare recurrence time of an isolated system, and innovation as trajectories not observed in isolated systems. As a case study, we implement novel variants of cellular automata (CA) where the update rules are allowed to vary with time in three alternative ways. Each is capable of generating conditions for open-ended evolution, but vary in their ability to do so. We find that state-dependent dynamics, regarded as a hallmark of life, statistically out-performs other candidate mechanisms, and is the only mechanism to produce open-ended evolution in a scalable manner, essential to the notion of ongoing evolution. This analysis suggests a new framework for unifying mechanisms for generating OEE with features distinctive to life and its artifacts, with broad applicability to biological and artificial systems.
Created2017-04-20
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Description

Cataclysmic Variables (CVs) are close binary star systems with one component a white dwarf (WD) and the other a larger cooler star that fills its Roche Lobe. The cooler star is losing mass through the inner Lagrangian point of the binary and some unknown fraction of this material is accreted

Cataclysmic Variables (CVs) are close binary star systems with one component a white dwarf (WD) and the other a larger cooler star that fills its Roche Lobe. The cooler star is losing mass through the inner Lagrangian point of the binary and some unknown fraction of this material is accreted by the WD. One consequence of the WDs accreting material, is the possibility that they are growing in mass and will eventually reach the Chandrasekhar Limit. This evolution could result in a Supernova Ia (SN Ia) explosion and is designated the Single Degenerate Progenitor (SD) scenario. This paper is concerned with the SD scenario for SN Ia progenitors. One problem with the single degenerate scenario is that it is generally assumed that the accreting material mixes with WD core material at some time during the accretion phase of evolution and, since the typical WD has a carbon-oxygen CO core, the mixing results in large amounts of carbon and oxygen being brought up into the accreted layers. The presence of enriched carbon causes enhanced nuclear fusion and a Classical Nova explosion.

Both observations and theoretical studies of these explosions imply that more mass is ejected than is accreted. Thus, the WD in a Classical Nova system is losing mass and cannot be a SN Ia progenitor. However, the composition in the nuclear burning region is important and, in new calculations reported here, the consequences to the WD of no mixing of accreted material with core material have been investigated so that the material involved in the explosion has only a Solar composition. WDs with a large range in initial masses and mass accretion rates have been evolved. I find that once sufficient material has been accreted, nuclear burning occurs in all evolutionary sequences and continues until a thermonuclear runaway (TNR) occurs and the WD either ejects a small amount of material or its radius grows to about 10[superscript 12] cm and the evolution is ended. In all cases where mass ejection occurs, the mass of the ejecta is far less than the mass of the accreted material. Therefore, all the WDs are growing in mass. It is also found that the accretion time to explosion can be sufficiently short for a 1.0M[subscript ⊙] WD that recurrent novae can occur on a low mass WD. This mass is lower than typically assumed for the WDs in recurrent nova systems. Finally, the predicted surface temperatures when the WD is near the peak of the explosion imply that only the most massive WDs will be significant X-ray emitters at this time.

Created2014-02-25
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The occurrence of nonliquid and liquid physical states of submicron atmospheric particulate matter (PM) downwind of an urban region in central Amazonia was investigated. Measurements were conducted during two intensive operating periods (IOP1 and IOP2) that took place during the wet and dry seasons of the GoAmazon2014/5 campaign. Air masses

The occurrence of nonliquid and liquid physical states of submicron atmospheric particulate matter (PM) downwind of an urban region in central Amazonia was investigated. Measurements were conducted during two intensive operating periods (IOP1 and IOP2) that took place during the wet and dry seasons of the GoAmazon2014/5 campaign. Air masses representing variable influences of background conditions, urban pollution, and regional- and continental-scale biomass burning passed over the research site. As the air masses varied, particle rebound fraction, an indicator of physical state, was measured in real time at ground level using an impactor apparatus. Micrographs collected by transmission electron microscopy confirmed that liquid particles adhered, while nonliquid particles rebounded. Relative humidity (RH) was scanned to collect rebound curves.

When the apparatus RH matched ambient RH, 95 % of the particles adhered as a campaign average. Secondary organic material, produced for the most part by the oxidation of volatile organic compounds emitted from the forest, produces liquid PM over this tropical forest. During periods of anthropogenic influence, by comparison, the rebound fraction dropped to as low as 60 % at 95 % RH. Analyses of the mass spectra of the atmospheric PM by positive-matrix factorization (PMF) and of concentrations of carbon monoxide, total particle number, and oxides of nitrogen were used to identify time periods affected by anthropogenic influences, including both urban pollution and biomass burning. The occurrence of nonliquid PM at high RH correlated with these indicators of anthropogenic influence. A linear model having as output the rebound fraction and as input the PMF factor loadings explained up to 70 % of the variance in the observed rebound fractions. Anthropogenic influences can contribute to the presence of nonliquid PM in the atmospheric particle population through the combined effects of molecular species that increase viscosity when internally mixed with background PM and increased concentrations of nonliquid anthropogenic particles in external mixtures of anthropogenic and biogenic PM.

ContributorsBateman, Adam P. (Author) / Gong, Zhaoheng (Author) / Harder, Tristan H. (Author) / de Sa, Suzane S. (Author) / Wang, Bingbing (Author) / Castillo, Paulo (Author) / China, Swarup (Author) / Liu, Yingjun (Author) / O'Brien, Rachel E. (Author) / Palm, Brett B. (Author) / Shiu, Hung-Wei (Author) / Cirino, Glauber G. (Author) / Thalman, Ryan (Author) / Adachi, Kouji (Author) / Alexander, M. Lizabeth (Author) / Artaxo, Paulo (Author) / Bertram, Allan K. (Author) / Buseck, Peter (Author) / Gilles, Mary K. (Author) / Jimenez, Jose L. (Author) / Laskin, Alexander (Author) / Manzi, Antonio O. (Author) / Sedlacek, Arthur (Author) / Souza, Rodrigo A. F. (Author) / Wang, Jian (Author) / Zaveri, Rahul (Author) / Martin, Scot T. (Author) / College of Liberal Arts and Sciences (Contributor) / School of Earth and Space Exploration (Contributor) / School of Molecular Sciences (Contributor)
Created2017-02-06