Browsing by Subject "longitudinal"

Now showing 1 - 5 of 5
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    Data from "Diverse Bacterial Communities Exist on Canine Skin and are Impacted by Cohabitation and Time"
    (2016-11-17) Johnson, Timothy; Torres, Sheila; Danzeisen, Jessica; Clayton, Jonathan; Ward, Tonya; Knights, Dan; Huang, Hu; joh04207@umn.edu; Johnson, Timothy
    This related study sampled 40 dogs from 20 households over the course of three seasons. Three skin sites were examined. The goal of the study was to determine if a core skin microbiome exists in dogs across time and body site, and if cohabitation impacts sharing of the skin microbiome. This dataset is a part of the Torres_Johnson Canine Microbiome Study.
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    Longitudinal changes in Go/No-Go and Stop Signal Task performance and relationships with gray matter architecture in adolescent development
    (2023-08) Weiss, Hannah
    This dissertation explores the development of response inhibition in adolescence to better understand risk-taking behaviors and risk for psychopathology. The first aim is to evaluate the longitudinal developmental trajectory of motor response inhibition among healthy adolescents and young adults using two tasks. The second aim is to explore relationships between regional gray matter architecture with individual differences and development of response inhibition. Research in this area has predominantly relied upon cross-sectional studies, used only one response inhibition task, lacked exploration of non-linear models, and rarely explored structural brain correlates of response inhibition. To address these limitations, this dissertation incorporated a longitudinal cohort sequential design (baseline ages 11 – 24, N = 148, up to four timepoints two years apart) to assess performance on two response inhibition tasks. Analyses included nonlinear models, retest stability estimates, and examination of between- and within-subjects associations of response inhibition with gray matter architecture. In Study 1, response inhibition as measured by the Stop Signal and Go/No-Go tasks demonstrated an inverse age trajectory with steepest improvements in early adolescence followed by stabilization. Neither task demonstrated sex effects, and each had fair retest stability. Building upon Study 1, Study 2 found that gray matter architecture of the inferior frontal gyrus was related to response inhibition. Distinct associations among gray matter measures, response inhibition tasks, and specific subregions of the inferior frontal gyrus were found. Collectively, this work characterizes the normative pattern of development of response inhibition in adolescence and identifies early adolescence as a specific period of plasticity and potential vulnerability that may be associated with gray matter development in the inferior frontal gyrus. It suggests that motor response inhibition is not a likely candidate for explaining peaks in risk-taking that occur in later adolescence. This work provides evidence for similarities and differences between the Go/No-Go and Stop Signal tasks and demonstrates strengths and weaknesses of each that may guide future research.
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    Perceived Impact of a Longitudinal Leadership Program for All Pharmacy Students
    (University of Minnesota, College of Pharmacy, 2014) Mort, Jane R.; Strain, Joe D.; Helgeland, David L.; Seefeldt, Teresa M.
    Objective: To describe a longitudinal leadership program involving all students and report the perceived impact. Design: The program included a first year Leadership Interview, a third year Report of Leadership, and a fourth year Professional Business Meeting Attendance. Activities involved guided reflection. Assessment: Students (n=138) indicated the activities helped them recognize the importance of leadership and their leadership potential (e.g., 72.5% and 62.3% of students due to meeting attendance, respectively). Students participated in leadership activities that they would not have pursued otherwise, either in response to the activity (27.7% due to interview) or as a requirement of the activity (51.1% for leadership report). Students reported developing specific leadership skills through the activities. Most students planned to be involved in a district/regional (72.5%), state (84.1%), and national (51.4%) meeting in the five years following graduation. Conclusion: Students reported a positive impact on leadership perceptions and participation. The report is a preliminary step in the development and assessment of a longitudinal curricular initiative involving all pharmacy students.
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    Precursors and Consequences of Partner Buffering of Attachment Insecurity for Agents in Romantic Relationships: An Examination of Two Longitudinal Studies
    (2022-06) Eller, Jami
    Insecurely attached people have less satisfying relationships, experience poorer psychological and physical health, and struggle to cope with stressful situations. Attachment insecurity, however, is modifiable. Indeed, individuals (agents) in romantic relationships can provide soothing comfort and tailored support that “buffers” or diminishes their partners’ (targets’) distress and insecurity. These supportive responses by agents are called buffering behaviors. Thus far, research has primarily examined how these responses allay insecurity and distress, thereby enhancing wellbeing and increasing security in many targets. Partner buffering, however, is a dyadic process that involves both targets and agents. Although some research has investigated targets, little is known about partner buffering from the agent’s perspective. Specifically, we do not know: (1) why some agents are more effective at buffering their partners than are other agents, or (2) what the long-term costs of engaging in buffering are for agents. Using data from two existing longitudinal studies, I documented whether and how certain personal and relational experiences shape agents' proclivity to engage in buffering behaviors (Studies 1 & 2), along with the long-term repercussions of buffering on agents’ individual and relationship wellbeing (Study 2). The current research suggests that agents are best equipped to engage in tailored and effective buffering behaviors when they (1) can regulate themselves, (2) have developed adequate social skills, and (3) are committed to maintaining their current relationship. Moreover, agents tend to benefit from engaging in buffering behaviors when their buffering is effective and when it is reciprocated.
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    The Social Pattern and Causes of Dementia Prevalence Decline in the United States
    (2022-07) Lee, Mark
    Age-adjusted dementia prevalence has significantly declined in the United States over the last 25 years, despite little advancement in the biomedical treatment of Alzheimer’s Disease or improvement in proximal dementia risk factors. In this dissertation, I analyze data from the Health and Retirement Study (HRS) to improve current understanding of the descriptive trends and causal mechanisms underlying dementia prevalence decline. In my first study, I rebut the argument that dementia decline in the HRS is an artefact of unmeasured panel conditioning. I show that practice effects do not bias the estimated secular trend in dementia prevalence after accounting for selective panel attrition. In my second study, I argue that cohort trends in early life risk factors offer a more plausible explanation of the observed dementia improvement than period trends, which have been emphasized in previous research. In my third study, I empirically test the contribution of early life risk factors to cohort trends in dementia prevalence. I find that age- and sex-adjusted dementia prevalence declined 2.3 percentage points per 10-year increase in birth year for cohorts born 1892-1952. The majority (72%) of this trend was explained by increases in educational attainment for more recent cohorts. Proximal risk factors had little influence net of education and other early life factors. The trend in dementia decline was steeper for Black than White Americans, and the causal mechanisms also differed by race. In my fourth study, I document cohort trends in midlife cognitive aging. I find that, compared with those born 1942-1947, those born 1954-1959 entered midlife with lower cognitive function, but exhibited greater maintenance of cognition over time. This suggests that dementia prevalence may continue to improve as this latter-born cohort ages. Overall, this research reinforces the importance of social improvement (especially educational expansion) across the 20th century for cognitive health improvements in the 21st century. This work indicates that interventions to reduce or delay dementia and ameliorate racial disparities should be expanded to include social determinants of health across the life course.