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Cardiovascular disease attributed to about 800,000 deaths per year and is the leading cause of all-cause mortality in the U.S. Previous studies indicate that reducing sedentary time or increasing physical activity (PA) can independently reduce cardiometabolic risk (CMR). Further, studies have shown that higher levels of moderate-to-vigorous PA can attenuate the negative effects of sedentary behavior on CMR.
In this study, we evaluated the association between sedentary time, light-intensity PA (LPA), and moderate-vigorous PA (MVPA) and CMR biomarkers (high density lipoprotein level, low density lipoprotein level, triglycerides, fasting glucose, total cholesterol, blood pressure, and body mass index). Additionally, we examined if the detrimental association between sedentary time and CMR biomarkers is partially or fully attenuated by MVPA. Baseline objective physical activity and cardiometabolic risk data from a two-arm-cluster randomized trial (Stand&Move@work) were used in this study. Multilevel models clustered by worksite evaluated the fixed effects and interaction between MVPA and sedentary time on CMR. Data from 630 sedentary working adults (from 24 worksites) were included in the analysis. The sample was mainly middle aged (44.6±11.2) females (74%) with race distributions as follows; 70.5% white, 13.8% hispanic, 4.1% black, 5.1% asian, and 2.1% other. Our study showed detrimental trends consistent with previous studies between sedentary behavior and cardiometabolic outcomes including HDL, LDL, and total cholesterol. MVPA demonstrated beneficial associations with lipoproteins including HDL, LDL, total cholesterol, and triglycerides. We observed that high levels of MVPA may be able to partially attenuate the negative effects of highly sedentary behavior on fasting glucose, total cholesterol, and LDL levels. Overall, sedentary behavior indicated deleterious associations with cardiometabolic outcomes. Future directions for this study could examine a more at-risk population or a highly active population for further assessment of CMR biomarkers and the effects of behavior.
In this study, we evaluated the association between sedentary time, light-intensity PA (LPA), and moderate-vigorous PA (MVPA) and CMR biomarkers (high density lipoprotein level, low density lipoprotein level, triglycerides, fasting glucose, total cholesterol, blood pressure, and body mass index). Additionally, we examined if the detrimental association between sedentary time and CMR biomarkers is partially or fully attenuated by MVPA. Baseline objective physical activity and cardiometabolic risk data from a two-arm-cluster randomized trial (Stand&Move@work) were used in this study. Multilevel models clustered by worksite evaluated the fixed effects and interaction between MVPA and sedentary time on CMR. Data from 630 sedentary working adults (from 24 worksites) were included in the analysis. The sample was mainly middle aged (44.6±11.2) females (74%) with race distributions as follows; 70.5% white, 13.8% hispanic, 4.1% black, 5.1% asian, and 2.1% other. Our study showed detrimental trends consistent with previous studies between sedentary behavior and cardiometabolic outcomes including HDL, LDL, and total cholesterol. MVPA demonstrated beneficial associations with lipoproteins including HDL, LDL, total cholesterol, and triglycerides. We observed that high levels of MVPA may be able to partially attenuate the negative effects of highly sedentary behavior on fasting glucose, total cholesterol, and LDL levels. Overall, sedentary behavior indicated deleterious associations with cardiometabolic outcomes. Future directions for this study could examine a more at-risk population or a highly active population for further assessment of CMR biomarkers and the effects of behavior.
ContributorsMeyer, Emily Camille (Author) / Buman, Matthew (Thesis director) / Toledo, Meynard (Committee member) / Pereira, Mark (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The International Space Station (ISS) utilizes recycled water for consumption, cleaning and air humidity control. The Environmental Control and Life Support Systems (ECLSS) have been rigorously tested at the NASA Johnson Space Center. Despite the advanced engineering of the water recovery system, bacterial biofilms have been recovered from this potable water source. Microbial contamination of potable water poses a potential threat to crew members onboard the ISS. Because astronauts have been found to have compromised immune systems, bacterial strains that would not typically be considered a danger must be carefully studied to better understand the mechanisms enabling their survival, including polymicrobial interactions. The need for a more thorough understanding of the effect of spaceflight environment on polymicrobial interactions and potential impact on crew health and vehicle integrity is heightened since 1) several potential pathogens have been isolated from the ISS potable water system, 2) spaceflight has been shown to induce unexpected alterations in microbial responses, and 3) emergent phenotypes are often observed when multiple bacterial species are co- cultured together, as compared to pure cultures of single species. In order to address these concerns, suitable growth media are required that will not only support the isolation of these microbes but also the ability to distinguish between them when grown as mixed cultures. In this study, selective and/or differential media were developed for bacterial isolates collected from the ISS potable water supply. In addition to facilitating discrimination between bacteria, the ideal media for each strain was intended to have a 100% recovery rate compared to traditional R2A media. Antibiotic and reagent susceptibility and resistance tests were conducted for the purpose of developing each individual medium. To study a wide range of targets, 12 antibiotics were selected from seven major classes, including penicillin, cephalosporins, fluoroquinolones, aminoglycosides, glycopeptides/lipoglycopeptides, macrolides/lincosamides/streptogramins, tetracyclines, in addition to seven unclassified antibiotics and three reagents. Once developed, medium efficacy was determined by means of growth curve experiments. The development of these media is a critical step for further research into the mechanisms utilized by these strains to survive the harsh conditions of the ISS water system. Furthermore, with an understanding of the complex nature of these polymicrobial communities, specific contamination targeting and control can be conducted to reduce the risk to crew members. Understanding these microbial species and their susceptibilities has potential application for future NASA human explorations, including those to Mars.
ContributorsKing, Olivia Grace (Author) / Nickerson, Cheryl (Thesis director) / Barrila, Jennifer (Committee member) / Ott, Mark (Committee member) / School of Sustainability (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
While type 2 diabetes (T2D) rates have soared, the number of Americans classified as ‘prediabetic’ has also increased. Despite this, current preventative approaches are costly and often not without undue side-effects. Instead, behavioral lifestyle approaches hold promise in reducing conversion rates of T2D as the latest treatment option that could mitigate and transform disease management. However, present interventions do not possess the scope necessary for implementation in a realistic, scalable way that can target the large at-risk population.
The application (app) “BeWell24” mitigates this diabetes risk through targeting sleep, physical activity, sedentary behavior, and diet, and is being delivered through mHealth technology to attenuate the higher-risk of the prediabetic Veteran population. In order for full scale dissemination, this thesis examines a provider perspective of the ‘Post-intervention interview guide’, performed with a Phoenix Veterans Affairs Health Care System (PVAHCS) provider. It then suggests revisions to the interview guide based on the provider’s interview and existing literature. This thesis also emphasizes the rationale behind these proposed changes to be organized in line with the iPARIHS framework (integrated Promoting Action on Research Implementation in Health Services).
Overall, the provider responded positively to BeWell24 and the ‘Post-intervention interview guide’, with constructive suggestions for each question in the interview guide. The main theme of the provider’s answers and comments were to prioritize efficiency and preserve standard clinical flow. A revised interview guide is provided, which prospectively presents as a more brief and focused interview organized by the iPARIHS framework. This revised interview guide could aid in the clarity of provider responses, specifically for the prospective interviews of the ongoing larger BeWell24 study and future studies.
The application (app) “BeWell24” mitigates this diabetes risk through targeting sleep, physical activity, sedentary behavior, and diet, and is being delivered through mHealth technology to attenuate the higher-risk of the prediabetic Veteran population. In order for full scale dissemination, this thesis examines a provider perspective of the ‘Post-intervention interview guide’, performed with a Phoenix Veterans Affairs Health Care System (PVAHCS) provider. It then suggests revisions to the interview guide based on the provider’s interview and existing literature. This thesis also emphasizes the rationale behind these proposed changes to be organized in line with the iPARIHS framework (integrated Promoting Action on Research Implementation in Health Services).
Overall, the provider responded positively to BeWell24 and the ‘Post-intervention interview guide’, with constructive suggestions for each question in the interview guide. The main theme of the provider’s answers and comments were to prioritize efficiency and preserve standard clinical flow. A revised interview guide is provided, which prospectively presents as a more brief and focused interview organized by the iPARIHS framework. This revised interview guide could aid in the clarity of provider responses, specifically for the prospective interviews of the ongoing larger BeWell24 study and future studies.
ContributorsWojtas, Abby Ann (Author) / Buman, Matthew (Thesis director) / Larouche, Miranda (Committee member) / Epstein, Dana (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Blood donations today undergo extensive screening for transfusion transmitted infections (TTI) since the discovery of the first infectious agent in the early 1900s. Nucleic Acid Testing (NAT) is a serological test used widely in disease detection. NAT is known to rapidly and effectively detect pathogenic genomic material in blood by reducing the "window period" of infection. However, NAT produces false negative results for disease positive samples posing a risk of disease transmission. Therefore, NAT is used in conjunction with the Enzyme-Linked Immunosorbent Assay (ELISA) to mitigate these risks. However, the ELISA assay also poses the same risk as NAT. This study proposes immunosignaturing as an alternative serological test that may combat this risk and investigates whether it would be more effective than other standardized serological tests in disease detection. Immunosignaturing detects antibodies by utilizing a microarray of randomized peptide sequences. Immunosignaturing provides information about an individual's immune health from the pattern of reactivity of antibody-peptide binding. Unlike ELISA and NAT, immunosignaturing can be programmed to detect any disease and detect multiple diseases simultaneously. Using ELISA, NAT, and immunosignaturing, immune profiles of asymptomatic patients were constructed for 10 different classes of blood borne diseases. A pattern of infection was identified for each disease and the sensitivity and specificity of these assays were assessed relative to each other. Results indicate that immunosignaturing can be a viable diagnostic tool in blood testing. Immunosignatures demonstrated increased sensitivity and specificity compared to ELISA and NAT in discerning disease positive and negative samples within and across different classes of disease.
ContributorsSharma, Megumi (Author) / McFadden, Grant (Thesis director) / Nickerson, Cheryl (Committee member) / Green, Alex (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Mobile health or "mHealth" defines a broad spectrum of medical or public health practice supported by mobile devices. The patient's perception of mobile health applications is the key point in confronting whether or not patients will utilize the tools at their disposal As such, the primary aim of this study was to examine participant feedback through quantitative and qualitative measures using the Therapy Evaluation Questionnaire and a patient interview, respectively, to further understand the patient rated acceptability of using BeWell24 and SleepWell24 for improving health outcomes. For BeWell24, it was hypothesized that patients who received the Multicomponent version would report higher acceptability scores than those randomized to the Health Education version. Furthermore, in regard to SleepWell24, it was hypothesized that the SleepWell24 patient would provide positive feedback and suggestions regarding their own experience with the SleepWell24 app. Data from this thesis was pulled from two ongoing randomized controlled trials currently being conducted at the Phoenix Veteran Affairs Health Care Service (PVACHS) and Mayo Clinic hospitals. Means, standard deviations, frequencies, and percentages were commuted to summarize demographics and TEQ scores. In addition, key concepts from a qualitative interview with a SleepWell24 participant were derived. The results showed a greater acceptability of the multicomponent versions of BeWell24 and SleepWell24 but a lower TEQ score of perceived usability. mHealth implementations pose a potential to become an important part of the health sector for establishing innovative approaches to delivering care, and while benefits have been highly praised, it is clear that the perceptions of mHealth must be positive if the technology is to transcend into a practical clinical setting.
ContributorsJimenez, Asael (Author) / Buman, Matthew (Thesis director) / Epstein, Dana (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Sleep diaries and actigraphy are two common methods used to assess sleep subjectively and objectively, respectively. Compared to the gold standard of sleep assessment, polysomnography, sleep diaries and actigraphic methods are more cost-effective and simpler to use. This study aimed to compare the sleep parameters derived from actigraphy and sleep diaries (total sleep time, sleep onset latency, number of awakenings, wake after sleep onset, percentage of time awake, and sleep efficiency). Based on results from previous similar studies, it was hypothesized that the sleep diaries would overestimate the total sleep time parameter and underestimate wake parameters. Twenty healthy young adults without sleep problems volunteered to participate. The participants wore an Actiwatch 2 on their wrist and filled out a sleep diary every morning for the duration of six days. A high intraclass correlation coefficient value between subjective and objective sleep was found for the parameter total sleep time, even though total sleep time was found to be slightly overestimated by the sleep diaries. Sleep onset latency, wake after sleep onset, number of awakenings, percentage of time awake, and sleep efficiency were underestimated by the sleep diaries and did not have high correlation values. Based off of the ICC results, there does not seem to be a strong correlation between the Actiwatch 2 and the sleep diaries, but looking at the Bland Altman plots, there seems to be agreement between the methods.
ContributorsRameshkumar, Aarthi (Author) / Buman, Matthew (Thesis director) / Petrov, Megan (Committee member) / Diaz-Piedra, Carolina (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2016-12
Description
Recent research has confirmed and revealed many physical and mental benefits of yoga. The practice of yoga has spread throughout the western world, where it is widely used for the purpose of exercise and fitness. Due to its rise in popularity, there is a need for research regarding the energy expenditure required for different types of yoga. The majority of the literature cites yoga as being an effective exercise for light intensity activity, but there are not as many studies attempting to determine if there are postures and sequences that can meet the requirements for moderate physical activity. In addition, there is a need to validate mobile devices with which to measure energy expenditure (EE) that are compatible with the dynamic movements that occur during yoga. The purpose of this study was to measure energy expenditure of twenty-two yoga practitioners of varying experience during a 30-minute Vinyasa flow yoga practice and from this data collection determine: if an ashtanga-based vinyasa yoga class meets the criteria for moderate intensity physical activity, the reliability between the Actigraph and Oxycon Mobile and the validity of an Actigraph GT3X device worn on the hip in estimating energy expenditure for ashtanga-based vinyasa flow yoga. The Actigraph GT3X and the Oxycon mobile were used to measure energy expenditure. Mean values for energy expenditure recorded by the Oxycon and Actigraph were 3.19 ± 0.42 METs and 1.16 ± 0.23 METs respectively, exhibiting a significant difference in data collection. There was no correlation between the values recorded by the two devices, indicating that the Actigraph was not consistent with the Oxycon Mobile (previously validated for measurement of EE). Results of this study indicate that this Vinyasa flow yoga sequence does satisfy the criteria for moderate intensity physical activity as defined by ACSM with an average EE of 3.19 ± 0.42 METs, and that the Actigraph GT3X is not an accurate device for measurement of EE for yoga.
ContributorsHand, Lindsay Gabrielle (Author) / Huberty, Jennifer (Thesis director) / Buman, Matthew (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
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
Traditional Reinforcement Learning (RL) assumes to learn policies with respect to reward available from the environment but sometimes learning in a complex domain requires wisdom which comes from a wide range of experience. In behavior based robotics, it is observed that a complex behavior can be described by a combination of simpler behaviors. It is tempting to apply similar idea such that simpler behaviors can be combined in a meaningful way to tailor the complex combination. Such an approach would enable faster learning and modular design of behaviors. Complex behaviors can be combined with other behaviors to create even more advanced behaviors resulting in a rich set of possibilities. Similar to RL, combined behavior can keep evolving by interacting with the environment. The requirement of this method is to specify a reasonable set of simple behaviors. In this research, I present an algorithm that aims at combining behavior such that the resulting behavior has characteristics of each individual behavior. This approach has been inspired by behavior based robotics, such as the subsumption architecture and motor schema-based design. The combination algorithm outputs n weights to combine behaviors linearly. The weights are state dependent and change dynamically at every step in an episode. This idea is tested on discrete and continuous environments like OpenAI’s “Lunar Lander” and “Biped Walker”. Results are compared with related domains like Multi-objective RL, Hierarchical RL, Transfer learning, and basic RL. It is observed that the combination of behaviors is a novel way of learning which helps the agent achieve required characteristics. A combination is learned for a given state and so the agent is able to learn faster in an efficient manner compared to other similar approaches. Agent beautifully demonstrates characteristics of multiple behaviors which helps the agent to learn and adapt to the environment. Future directions are also suggested as possible extensions to this research.
ContributorsVora, Kevin Jatin (Author) / Zhang, Yu (Thesis advisor) / Yang, Yezhou (Committee member) / Praharaj, Sarbeswar (Committee member) / Arizona State University (Publisher)
Created2021
Description
Mycobacterial infections, as represented by leprosy and tuberculosis, have persisted as human pathogens for millennia. Their environmental counterparts, nontuberculous mycobacteria (NTM), are commodious infectious agents endowed with extensive innate and acquired antimicrobial resistance. The current drug development process selects for antibiotics with high specificity for definitive targets within bacterial metabolic and replication pathways. Because these compounds demonstrate limited efficacy against mycobacteria, novel antimycobacterial agents with unconventional mechanisms of action were identified. Two highly resistant NTMs, Mycobacterium abscessus (Mabs) a rapid-growing respiratory, skin, and soft tissue pathogen, and Mycobacterium ulcerans (MU), the causative agent of Buruli ulcer, were selected as targets. Compounds that indicated antimicrobial activity against other highly resistant pathogens were selected for initial screening. Antimicrobial peptides (AMPs) have demonstrated activity against a variety of bacterial pathogens, including mycobacterial species. Designed antimicrobial peptides (dAMPs), rationally-designed and synthetic contingents, combine iterative features of natural AMPs to achieve superior antimicrobial activity in resistant pathogens. Initial screening identified two dAMPs, RP554 and RP557, with bactericidal activity against Mabs. Clay-associated ions have previously demonstrated bactericidal activity against MU. Synthetic and customizable aluminosilicates have also demonstrated adsorption of bacterial cells and toxins. On this basis, two aluminosilicate materials, geopolymers (GP) and ion-exchange nanozeolites (IE-nZeos), were screened for antimicrobial activity against MU and its fast-growing relative, Mycobacterium marinum (Mmar). GPs demonstrated adsorption of MU cells and mycolactone, a secreted, lipophilic toxin, whereas Cu-nZeos and Ag-nZeos demonstrated antibacterial activity against MU and Mmar. Cumulatively, these results indicate that an integrative drug selection process may yield a new generation of antimycobacterial agents.
ContributorsDermody, Roslyn June (Author) / Haydel, Shelley E (Thesis advisor) / Bean, Heather (Committee member) / Nickerson, Cheryl (Committee member) / Stephanopoulos, Nicholas (Committee member) / Arizona State University (Publisher)
Created2022