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- Member of: ASU Electronic Theses and Dissertations
Description
Natural history is, and was, dependent upon the collection of specimens. In the nineteenth century, American naturalists and institutions of natural history cultivated and maintained extensive collection networks comprised of numerous collectors that provided objects of natural history for study. Effective networks were collaborative in nature, with naturalists such as Spencer Baird of the Smithsonian trading their time and expertise for specimens. The incorporation of Darwinian and Neo-Lamarckian evolutionary theory into natural history in the middle of the century led to dramatic changes in the relationship between naturalists and collectors, as naturalists sought to reconcile their observations within the new evolutionary context. This dissertation uses the careers of collectors Robert Kennicott, Frank Stephens, Edward W. Nelson, E.A. Goldman, and Edmund Heller as case studies in order to evaluate how the changes in the theoretical framework of late nineteenth century natural history led to advances in field practice by assessing how naturalists trained their collectors to meet new demands within the field. Research focused on the correspondence between naturalists and collectors, along with the field notes and applicable publications by collectors. I argue that the changes in natural history necessitated naturalists training their collectors in the basics of biogeography - the study of geographic distribution of organisms, and systematics - the study of the diversity of life - leading to a collaborative relationship in which collectors played an active role in the formation of new biological knowledge. The project concludes that the changes in natural history with regard to theory and practice gradually necessitated a more professional cadre of collectors. Collectors became active agents in the formation of biological knowledge, and instrumental in the formation of a truly systematic natural history. As a result, collectors became de facto field naturalists, the forerunners of the field biologists that dominated the practice of natural history in the early and middle twentieth century.
ContributorsLaubacher, Matthew (Author) / Green, Monica (Thesis advisor) / Laubichler, Manfred (Thesis advisor) / Wright, Johnson Kent (Committee member) / Arizona State University (Publisher)
Created2011
Description
Once perceived as an unimportant occurrence in living organisms, cell degeneration was reconfigured as an important biological phenomenon in development, aging, health, and diseases in the twentieth century. This dissertation tells a twentieth-century history of scientific investigations on cell degeneration, including cell death and aging. By describing four central developments in cell degeneration research with the four major chapters, I trace the emergence of the degenerating cell as a scientific object, describe the generations of a variety of concepts, interpretations and usages associated with cell death and aging, and analyze the transforming influences of the rising cell degeneration research. Particularly, the four chapters show how the changing scientific practices about cellular life in embryology, cell culture, aging research, and molecular biology of Caenorhabditis elegans shaped the interpretations about cell degeneration in the twentieth-century as life-shaping, limit-setting, complex, yet regulated. These events created and consolidated important concepts in life sciences such as programmed cell death, the Hayflick limit, apoptosis, and death genes. These cases also transformed the material and epistemic practices about the end of cellular life subsequently and led to the formations of new research communities. The four cases together show the ways cell degeneration became a shared subject between molecular cell biology, developmental biology, gerontology, oncology, and pathology of degenerative diseases. These practices and perspectives created a special kind of interconnectivity between different fields and led to a level of interdisciplinarity within cell degeneration research by the early 1990s.
ContributorsJiang, Lijing (Author) / Maienschein, Jane (Thesis advisor) / Laubichler, Manfred (Thesis advisor) / Hurlbut, James (Committee member) / Creath, Richard (Committee member) / White, Michael (Committee member) / Arizona State University (Publisher)
Created2013
Description
This dissertation investigates the condition of skeletal muscle insulin resistance using bioinformatics and computational biology approaches. Drawing from several studies and numerous data sources, I have attempted to uncover molecular mechanisms at multiple levels. From the detailed atomistic simulations of a single protein, to datamining approaches applied at the systems biology level, I provide new targets to explore for the research community. Furthermore I present a new online web resource that unifies various bioinformatics databases to enable discovery of relevant features in 3D protein structures.
ContributorsMielke, Clinton (Author) / Mandarino, Lawrence (Committee member) / LaBaer, Joshua (Committee member) / Magee, D. Mitchell (Committee member) / Dinu, Valentin (Committee member) / Willis, Wayne (Committee member) / Arizona State University (Publisher)
Created2013
Description
Gene-centric theories of evolution by natural selection have been popularized and remain generally accepted in both scientific and public paradigms. While gene-centrism is certainly parsimonious, its explanations fall short of describing two patterns of evolutionary and social phenomena: the evolution of sex and the evolution of social altruism. I review and analyze current theories on the evolution of sex. I then introduce the conflict presented to gene-centric evolution by social phenomena such as altruism and caste sterility in eusocial insects. I review gene-centric models of inclusive fitness and kin selection proposed by Hamilton and Maynard Smith. Based their assumptions, that relatedness should be equal between sterile workers and reproductives, I present several empirical examples that conflict with their models. Following that, I introduce a unique system of genetic caste determination (GCD) observed in hybrid populations of two sister-species of seed harvester ants, Pogonomyrmex rugosus and Pogonomyrmex barbatus. I review the evidence for GCD in those species, followed by a critique of the current gene-centric models used to explain it. In chapter two I present my own theoretical model that is both simple and extricable in nature to explain the origin, evolution, and maintenance of GCD in Pogonomyrmex. Furthermore, I use that model to fill in the gaps left behind by the contributing authors of the other GCD models. As both populations in my study system formed from inter-specific hybridization, I review modern discussions of heterosis (also called hybrid vigor) and use those to help explain the ecological competitiveness of GCD. I empirically address the inbreeding depression the lineages of GCD must overcome in order to remain ecologically stable, demonstrating that as a result of their unique system of caste determination, GCD lineages have elevated recombination frequencies. I summarize and conclude with an argument for why GCD evolved under selective mechanisms which cannot be considered gene-centric, providing evidence that natural selection can effectively operate on non-heritable genotypes appearing in groups and other social contexts.
ContributorsJacobson, Neal (Author) / Gadau, Juergen (Thesis advisor) / Laubichler, Manfred (Committee member) / Pratt, Stephen (Committee member) / Arizona State University (Publisher)
Created2012
Description
While exercising mammalian muscle increasingly relies on carbohydrates for fuel as aerobic exercise intensity rises above the moderate range, flying birds are extraordinary endurance athletes and fuel flight, a moderate-high intensity exercise, almost exclusively with lipid. In addition, Aves have long lifespans compared to weight-matched mammals. As skeletal muscle mitochondria account for the majority of oxygen consumption during aerobic exercise, the primary goal was to investigate differences in isolated muscle mitochondria between these species and to examine to what extent factors intrinsic to mitochondria may account for the behavior observed in the intact tissue and whole organism. First, maximal enzyme activities were assessed in sparrow and rat mitochondria. Citrate synthase and aspartate aminotransferase activity were higher in sparrow compared to rat mitochondria, while glutamate dehydrogenase activity was lower. Sparrow mitochondrial NAD-linked isocitrate dehydrogenase activity was dependent on phosphate, unlike the mammalian enzyme. Next, the rate of oxygen consumption (JO), electron transport chain (ETC) activity, and reactive oxygen species (ROS) production were assessed in intact mitochondria. Maximal rates of fat oxidation were lower than for carbohydrate in rat but not sparrow mitochondria. ETC activity was higher in sparrows, but no differences were found in ROS production between species. Finally, fuel selection and control of respiration at three rates between rest and maximum were assessed. Mitochondrial fuel oxidation and selection mirrored that of the whole body; in rat mitochondria the reliance on carbohydrate increased as the rate of oxygen consumption increased, whereas fat dominated under all conditions in the sparrow. These data indicate fuel selection, at least in part, can be modulated at the level of the mitochondrial matrix when multiple substrates are present at saturating levels. As an increase in matrix oxidation-reduction potential has been linked to a suppression of fat oxidation and high ROS production, the high ETC activity relative to dehydrogenase activity in avian compared to mammalian mitochondria may result in lower matrix oxidation-reduction potential, allowing fatty acid oxidation to proceed while also resulting in low ROS production in vivo.
ContributorsKuzmiak, Sarah (Author) / Willis, Wayne T (Thesis advisor) / Mandarino, Lawrence (Committee member) / Sweazea, Karen (Committee member) / Harrison, Jon (Committee member) / Gadau, Juergen (Committee member) / Arizona State University (Publisher)
Created2012
Description
Meditation app usage is associated with decreases in stress, anxiety, and depression symptoms. Many meditation app subscribers, however, quickly abandon or reduce their app usage. This dissertation presents three manuscripts which 1) determined the behavioral, demographic, and socioeconomic factors associated with the abandonment of a meditation app, Calm, during the COVID-19 pandemic, 2) determined which participant characteristics predicted meditation app usage in the first eight weeks after subscribing, and 3) determined if changes in stress, anxiety, and depressive symptoms from baseline to Week 8 predicted meditation app usage from Weeks 8-16. In Manuscript 1, a survey was distributed to Calm subscribers in March 2020 that assessed meditation app behavior and meditation habit strength, and demographic information. Cox proportional hazards regression models were estimated to assess time to app abandonment. In Manuscript 2, new Calm subscribers completed a baseline survey on participants’ demographic and baseline mental health information and app usage data were collected over 8 weeks. In Manuscript 3, new Calm subscribers completed a baseline and Week 8 survey on demographic and mental health information. App usage data were collected over 16 weeks. Regression models were used to assess app usage for Manuscripts 2 and 3. Findings from Manuscript 1 suggest meditating after an existing routine decreased risk of app abandonment for pre-pandemic subscribers and for pandemic subscribers. Additionally, meditating “whenever I can” decreased risk of abandonment among pandemic subscribers. No behavioral factors were significant predictors of app abandonment among the long-term subscribers. Findings from Manuscript 2 suggest men had more days of meditation than women. Mental health diagnosis increased average daily meditation minutes. Intrinsic motivation for meditation increased the likelihood of completing any meditation session, more days with meditation sessions, and more average daily meditation minutes. Findings from Manuscript 3 suggest improvements in stress increased average daily meditation minutes. Improvements in depressive symptoms decreased daily meditation minutes. Evidence from this three-manuscript dissertation suggests meditation cue, time of day, motivation, symptom changes, and demographic and socioeconomic variables may be used to predict meditation app usage.
ContributorsSullivan, Mariah (Author) / Stecher, Chad (Thesis advisor) / Huberty, Jennifer (Committee member) / Buman, Matthew (Committee member) / Larkey, Linda (Committee member) / Chung, Yunro (Committee member) / Arizona State University (Publisher)
Created2022
Description
How is knowledge created at the intersections between basic science, biotechnology, and industry? Gene drives are an interesting example, as they combine a long-standing interest with a recent technological breakthrough and a new set of commercial applications. Gene drives are genes engineered such that they are preferentially inherited at a frequency greater than the typical Mendelian fifty percent ratio. During the historical and conceptual evolution of gene drives beginning in the 1960s, there have been many innovations and publications. Along with that, gene drive science developed considerable public attention, explosion of new scientists, and variation in the way the topic is discussed. It is now time to look at this new organization of science using a systematic approach to characterize the system that has enabled knowledge to grow in this scientific field. This project breaks new ground in how knowledge advances in genetic engineering science, and how scientists understand what a “gene drive” is through analysis of language, communities, and other social factors. In effect, this research will advance multiple fields and enable a deeper understanding of knowledge and complexity. This project documents patterns of publication, collaborative relationships, linguistic variation, innovation, and knowledge expansion. The results of computational analysis provide an in-depth and complete characterization of the structure, dynamics, and evolution of scientific knowledge found in the gene drive technology. Further, time series analysis of the multiple layers of discourse enabled a diachronic connective mapping of collaborative relationships and tracked linguistic variation and change, highlighting where ambiguous language may appear, improving and creating more cohesive scientific language.
Overall, depicting the structure, dynamics, and evolution of scientific knowledge during a novel eruption of scientific complexity can shed light on the factors that can lead to: (1) improved scientific communication, (2) reduction of scientific progress, (3) new knowledge, and (4) novel collaborative relationships. Therefore, characterizing the current technological, methodological, and social contexts that can influence scientific knowledge.
ContributorsOToole, Cody Lane (Author) / Laubichler, Manfred (Thesis advisor) / Collins, James P (Committee member) / Simeone, Michael (Committee member) / Evans, James (Committee member) / Arizona State University (Publisher)
Created2021
Description
Young adult collegiate women, particularly students with adverse childhood experiences (ACEs) and who have experienced intimate partner violence (IPV) victimization, report a myriad of adverse mental health and academic difficulties. Practicing yoga has demonstrated promising findings among adults as a healing modality in the aftermath of interpersonal violence victimization and traumatization. Less known are the associations between collegiate women’s yoga participation and their mental health, body connection, and academic well-being examined through a yoga feminist- trauma conceptual framework. Among young adult collegiate women, this study examined (1) associations amongst socio-demographics, mental health service use, IPV types, and yoga participation (2) the strength and direction of associations on measures of ACEs, mental health, body connection, and academic well-being, (3) whether yoga participation predicted students’ mental health, body connection, and academic well-being after controlling for confounding variables, including ACEs and IPV victimization, and (4) whether socio-demographics, mental health service use, ACEs, and IPV types predicted yoga participation. This study was observational, cross-sectional, and gathered self-report quantitative data. Eligible participants were current collegiate women enrolled at an urban, public university in the southwestern United States who were 18 to 24 years of age. The main sub-sample (n = 93) included students who were ever in an intimate relationship and practiced yoga within the past year. IRB approval was obtained. Findings demonstrated that yoga participation was not a significant predictor of students’ mental health, body connection, or academic well-being. Socio-demographics, mental health service use, ACEs, and IPV did not predict yoga participation. However, women with greater ACEs fared worse on measures of mental health (i.e., depression and post-traumatic stress disorder symptoms), and women with experiences of IPV harassment reported greater post-traumatic stress disorder symptoms. Further, employed women reported fewer depression symptoms and were less likely to experience emotional IPV. Lastly, students with greater body connection (more awareness) fared better academically. This research supports prior literature on the adverse mental health outcomes among young adult collegiate women with histories of interpersonal violence. Further examination is warranted into employment and body connection, particularly related to yoga, as protective factors of students' health, safety, and academic well-being.
ContributorsKappas Mazzio, Andrea Alexa (Author) / Messing, Jill T (Thesis advisor) / Mendoza, Natasha (Committee member) / Huberty, Jennifer (Committee member) / Arizona State University (Publisher)
Created2022
Description
Scientific researchers have studied microorganisms since the emergence of the single lens microscope in the 17th century. Since then, researchers designed and published many thousands of images to record and share their observations, including hand-drawn diagrams, photomicrographs, and photographs. Images shaped how researchers conceived of microorganisms, their concepts of microorganisms shaped their images, and their images and concepts were shaped by the contexts in which they were working. Over time, the interplay of images and concepts in various research contexts participated in the development of new concepts related to microorganisms, like the “biofilm” concept, or the idea that bacteria exist in nature as complex aggregates attached to surfaces via extracellular polymeric matrices. Many histories of microbiology locate the origin of the biofilm concept in the 1970s, but that date obscures the rich history of research about attached microbial aggregates that occurred throughout the history of microbiology. I discovered how the interplay of images and concepts related to bacteria participated in the development of the biofilm concept by documenting when and why researchers used different visual features to represent changing concepts related to microorganisms. I specifically examined how and why scientists represented evolving concepts related to bacteria during the 17th century (Chapter 1), from the late 17th century to the early 20th century (Chapter 2), and during the first seventy-four years of the 20th century (Chapter 3). I discovered the biofilm concept developed in at least three unique research contexts during the 20th century, and how images reflected and shaped the concept’s development in each case. The narrative and collection of images generated from this work serve as a visual history of the development of scientists’ ideas about the nature of bacteria over 300 years.
ContributorsGuerrero, Anna Clemencia (Author) / Maienschein, Jane (Thesis advisor) / Laubichler, Manfred (Committee member) / Sterner, Beckett (Committee member) / Matlin, Karl (Committee member) / Arizona State University (Publisher)
Created2023
Description
Abortion is a controversial topic internationally. Most current debates about abortion concern when, if at all, it should be legal. However, researchers have shown many times that after an abortion ban, maternal and infant mortalities rise significantly, as women who seek out abortions do so regardless of abortion legality. So, is it possible to reduce abortions in a population without delegalizing abortion and, if so, how? Why do some countries have higher abortion rates than others in the presence of the same law?This dissertation answers both questions. First, I present historical evidence in the first comprehensive comparative analysis of all 15 post-Soviet countries, which have very similar abortion laws originating from the Union of Soviet Socialist Republics (USSR). Second, I use those findings to build the first agent-based model (ABM) of unintended pregnancies in a hypothetical artificial population.
USSR was the only country in the world to complete its demographic transition through abortion instead of modern contraception, and the Soviet government passed the first law in the world to allow abortion upon request in 1920. After the USSR dissolution in 1991, post-Soviet countries maintained very similar abortion laws, but had very different abortion rates for most years. Analysis of fertility data from post-Soviet countries shows that the prevalence of some specific contraceptive methods, namely the rhythm method (r = 0.82), oral pill (r = 0.56), and male condom (r = 0.51) are most strongly correlated with high abortion rates, and that sex education is a factor that reduces the rates in otherwise similar countries (p = 0.02).
The ABM shows that even basic sex education results in fewer abortions than no sex education or abstinence-based sex education (p < 0.01). In scenarios without sex education, basic quality of post-abortion contraceptive counseling (PACC) is better than no PACC or low-quality PACC at reducing abortions (p < 0.01). Still, the higher the quality of sex education or PACC, the fewer abortions in the artificial population. The ABM is adaptive and policy makers can use it as a decision-support tool to make evidence-based policy decisions regarding abortion, and, potentially, other sociobiological phenomena with some adjustments to the code.
ContributorsZiganshina Lienhard, Dina A. (Author) / Maienschein, Jane (Thesis advisor) / Gaughan, Monica (Thesis advisor) / Laubichler, Manfred (Committee member) / Ellison, Karin (Committee member) / Arizona State University (Publisher)
Created2023