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In 2010, a monthly sampling regimen was established to examine ecological differences in Saguaro Lake and Lake Pleasant, two Central Arizona reservoirs. Lake Pleasant is relatively deep and clear, while Saguaro Lake is relatively shallow and turbid. Preliminary results indicated that phytoplankton biomass was greater by an order of magnitude

In 2010, a monthly sampling regimen was established to examine ecological differences in Saguaro Lake and Lake Pleasant, two Central Arizona reservoirs. Lake Pleasant is relatively deep and clear, while Saguaro Lake is relatively shallow and turbid. Preliminary results indicated that phytoplankton biomass was greater by an order of magnitude in Saguaro Lake, and that community structure differed. The purpose of this investigation was to determine why the reservoirs are different, and focused on physical characteristics of the water column, nutrient concentration, community structure of phytoplankton and zooplankton, and trophic cascades induced by fish populations. I formulated the following hypotheses: 1) Top-down control varies between the two reservoirs. The presence of piscivore fish in Lake Pleasant results in high grazer and low primary producer biomass through trophic cascades. Conversely, Saguaro Lake is controlled from the bottom-up. This hypothesis was tested through monthly analysis of zooplankton and phytoplankton communities in each reservoir. Analyses of the nutritional value of phytoplankton and DNA based molecular prey preference of zooplankton provided insight on trophic interactions between phytoplankton and zooplankton. Data from the Arizona Game and Fish Department (AZGFD) provided information on the fish communities of the two reservoirs. 2) Nutrient loads differ for each reservoir. Greater nutrient concentrations yield greater primary producer biomass; I hypothesize that Saguaro Lake is more eutrophic, while Lake Pleasant is more oligotrophic. Lake Pleasant had a larger zooplankton abundance and biomass, a larger piscivore fish community, and smaller phytoplankton abundance compared to Saguaro Lake. Thus, I conclude that Lake Pleasant was controlled top-down by the large piscivore fish population and Saguaro Lake was controlled from the bottom-up by the nutrient load in the reservoir. Hypothesis 2 stated that Saguaro Lake contains more nutrients than Lake Pleasant. However, Lake Pleasant had higher concentrations of dissolved nitrogen and phosphorus than Saguaro Lake. Additionally, an extended period of low dissolved N:P ratios in Saguaro Lake indicated N limitation, favoring dominance of N-fixing filamentous cyanobacteria in the phytoplankton community in that reservoir.
ContributorsSawyer, Tyler R (Author) / Neuer, Susanne (Thesis advisor) / Childers, Daniel L. (Committee member) / Sommerfeld, Milton (Committee member) / Arizona State University (Publisher)
Created2011
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Description
It is well known that deficiencies in key chemical elements (such as phosphorus, P) can reduce animal growth; however, recent empirical data have shown that high levels of dietary nutrients can also reduce animal growth. In ecological stoichiometry, this phenomenon is known as the "stoichiometric knife edge," but its underlying

It is well known that deficiencies in key chemical elements (such as phosphorus, P) can reduce animal growth; however, recent empirical data have shown that high levels of dietary nutrients can also reduce animal growth. In ecological stoichiometry, this phenomenon is known as the "stoichiometric knife edge," but its underlying mechanisms are not well-known. Previous work has suggested that the crustacean zooplankter Daphnia reduces its feeding rates on phosphorus-rich food, causing low growth due to insufficient C (energy) intake. To test for this mechanism, feeding rates of Daphnia magna on algae (Scenedesmus acutus) differing in C:P ratio (P content) were determined. Overall, there was a significant difference among all treatments for feeding rate (p < 0.05) with generally higher feeding rates on P-rich algae. These data indicate that both high and low food C:P ratio do affect Daphnia feeding rate but are in contradiction with previous work that showed that P-rich food led to strong reductions in feeding rate. Additional experiments are needed to gain further insights.
ContributorsSchimpp, Sarah Ann (Author) / Elser, James (Thesis director) / Neuer, Susanne (Committee member) / Peace, Angela (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Sustainability (Contributor)
Created2014-05
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Description
Microzooplankton, mainly heterotrophic unicellular eukaryotes (protists), play an important role in the cycling of nutrients and carbon in the sunlit (euphotic) zone of the world’s oceans. Few studies have investigated the microzooplankton communities in oligotrophic (low-nutrient) oceans, such as the Sargasso Sea. In this study, I investigate the seasonal and

Microzooplankton, mainly heterotrophic unicellular eukaryotes (protists), play an important role in the cycling of nutrients and carbon in the sunlit (euphotic) zone of the world’s oceans. Few studies have investigated the microzooplankton communities in oligotrophic (low-nutrient) oceans, such as the Sargasso Sea. In this study, I investigate the seasonal and interannual dynamics of the heterotrophic protists, particularly the nanoflagellate, dinoflagellate, and ciliate communities, at the Bermuda Atlantic Time Series site and surrounding areas in the Sargasso Sea. In addition, I test the hypotheses that the community is controlled though bottom-up and top-down processes. To evaluate the bottom-up hypothesis, that the protists are controlled by prey availability, I test whether the protist abundance co-varies with the abundance of potential prey groups. Predation experiments with zooplankton were conducted and analyzed to test top-down control on the protists. I found distinguishable trends in biomass of the different protist groups between years and seasons. Nanoflagellates and dinoflagellates had higher biomass during the summer (28 ± 5 mgC/m2 and 44 ± 21 mgC/m2) than during the winter (17 ± 8 mgC/m2 and 30 ± 11 mgC/m2). Ciliates displayed the opposite trend with a higher average biomass in the winter (15 ± 9 mgC/m2) than in summer (5 ± 2 mgC/m2). In testing my bottom-up hypothesis, I found weak but significant positive grazer/prey relationships that indicate that nanoflagellates graze on picophytoplankton in winter and on the pico-cyanobacterium Prochlorococcus in summer. I found evidence that ciliates graze on Synechococcus in winter. I found weak but significant negative correlation between dinoflagellates and Prochlorococcus in summer. The predation experiments testing the top-down hypothesis did not show a clear top-down control, yet other studies in the region carried out during our investigation period support predation of the protists by the zooplankton. Overall, my results suggest a combination of bottom-up and top-down controls on these heterotrophic protists, however, further investigation is necessary to reveal the detailed trophic dynamics of these communities.
ContributorsWolverton, Megan (Author) / Neuer, Susanne (Thesis advisor) / Hartnett, Hillary (Committee member) / Elser, James (Committee member) / Arizona State University (Publisher)
Created2016
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Description

Extreme heat is the deadliest weather and climate-related hazard in the United States, and the threat it poses to urban residents is rising. City planners increasingly recognize these risks and are taking action to mitigate them. However, the COVID-19 pandemic has disrupted many plans. Building on a

Extreme heat is the deadliest weather and climate-related hazard in the United States, and the threat it poses to urban residents is rising. City planners increasingly recognize these risks and are taking action to mitigate them. However, the COVID-19 pandemic has disrupted many plans. Building on a previous survey which queried city planners from across the United States about how concerned they were about extreme heat, and their heat management efforts. This thesis examines how these perceptions and efforts have changed in the face of the COVID-19 pandemic. In general, it was found that public spaces which would typically have been used to shelter individuals from extreme heat conditions were closed to mitigate close-contact and to encourage social distancing. Furthermore, priorities were changed as the presence of the virus became commonplace, with plans being altered, delayed, or shelved to diverge more time and effort towards the crisis at hand. Working environments and conditions also changed, which in several cases led to technological shortcomings, resulting in further delays. Finally, most planners had attained a surface-level understanding of which socio-economic groups were most impacted by both COVID-19 and extreme heat, in congruence with the current literature written on the topic. Generally, it appears that planners feel that the impact of COVID-19 on heat planning efforts has been limited.

ContributorsNorris, Walker Yale (Author) / Meerow, Sara (Thesis director) / Keith, Ladd (Committee member) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsQian, Michael (Co-author) / Cosgrove, Samuel (Co-author) / English, Corinne (Co-author) / Agee, Claire (Co-author) / Mattson, Kyle (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / School of Accountancy (Contributor) / Department of Finance (Contributor) / Department of Information Systems (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsEnglish, Corinne (Co-author) / Cosgrove, Samuel (Co-author) / Mattson, Kyle (Co-author) / Agee, Claire (Co-author) / Qian, Michael (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / Department of Information Systems (Contributor) / Department of Supply Chain Management (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsAgee, Claire (Co-author) / English, Corinne (Co-author) / Mattson, Kyle (Co-author) / Qian, Michael (Co-author) / Cosgrove, Samuel (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / Department of Finance (Contributor) / Department of Supply Chain Management (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsMattson, Kyle (Co-author) / Agee, Claire (Co-author) / English, Corinne (Co-author) / Cosgrove, Samuel (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / Department of Marketing (Contributor) / Department of Supply Chain Management (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

Healthcare facilities are essential for any community, and they must stay up-to-date with the latest equipment and technology. They provide necessary resources for keeping populations healthy and safe. In order to provide healthcare services, these healthcare facilities must be adequately equipped with appropriate physical capital as well as software to

Healthcare facilities are essential for any community, and they must stay up-to-date with the latest equipment and technology. They provide necessary resources for keeping populations healthy and safe. In order to provide healthcare services, these healthcare facilities must be adequately equipped with appropriate physical capital as well as software to meet the demands of their patients. Healthcare capital equipment planning involves building up a facility with all it’s equipment and is a part of the healthcare supply chain. Attainia is a healthcare capital equipment planning software used to assist equipment planners in organizing the procurement of equipment for their projects. Attainia has a large amount of data about the capital equipment supply chain through the Attainia equipment catalog. Analysis of this catalog data reveals different patterns in the spending patterns of capital equipment planners as well as trends in the supplier offerings. Since Attainia itself is a software, Attainia’s users have experience with implementing and integrating software into healthcare IT solutions. Their experiences give some insight into the complex nature of software implementations at healthcare facilities. The COVID-19 pandemic has affected healthcare facilities all over the world. Impacting the supply chain and hitting hospitals’ finances, COVID-19 has drastically changed many parts of the healthcare system. This paper will examine some of these ongoing effects from COVID-19 along with analysis on capital equipment planning, supply chain, and healthcare software implementation.

ContributorsShah, Shailee (Author) / Pye, Jessica (Thesis director) / Roumina, Kavous (Committee member) / School of International Letters and Cultures (Contributor) / Department of Information Systems (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

The SARS-CoV-2 (Covid-19) virus has had severe impacts on college students' ways of life. To examine how students were coping and perceiving the Covid-19 pandemic, a secondary analysis of an online survey across the three Arizona public universities investigated students’ knowledge about Covid-19, engagement with preventive strategies, pandemic preparedness and

The SARS-CoV-2 (Covid-19) virus has had severe impacts on college students' ways of life. To examine how students were coping and perceiving the Covid-19 pandemic, a secondary analysis of an online survey across the three Arizona public universities investigated students’ knowledge about Covid-19, engagement with preventive strategies, pandemic preparedness and gauged their risk perception. Results from our analysis indicate that the students were knowledgeable about Covid-19 and were changing their habits and engaging with preventive measures. Results further suggest that students were prepared for the pandemic in terms of resources and were exhibiting high-risk perceptions. The data also revealed that students who were being cautious and engaging with preventive behaviors had a higher risk-perception than individuals who were not. As for individuals who were prepared for the pandemic in terms of supplies, their risk perception was similar to those who did not have supplies. Individuals who were prepared and capable of providing a single caretaker to tend to their sick household members and isolate them in a separate room had a higher risk perception than those who could not. These results can help describe how college students will react to a future significant event, what resources students may be in need of, and how universities can take additional steps to keep their students safe and healthy. The results from this study and recommendations will provide for a stronger and more understanding campus community during times of distress and can improve upon already established university protocols for health crises and even natural disasters.

ContributorsNaqvi, Avina Itrat (Co-author) / Shaikh, Sara (Co-author) / Jehn, Megan (Thesis director) / Adams, Marc (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05