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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Facilitating Multiple Cue Use Eliminates Age Differences in Episodic Metamemory for Emotional Words

Flurry, Ethan 06 August 2021 (has links)
Older adults' ability to make accurate metamemory judgments indicates that aging spares metamemory (Eakin & Hertzog, 2006; 2012a; but see Souchay et al., 2006). However, age differences in metamemory accuracy for emotional information, particularly lists of positive and neutral words, indicate potential age-related impairment of metamemory (Tauber & Dunlosky, 2012; Flurry & Eakin, manuscript in preparation). These age differences may be explained by potential cue overshadowing effects (Price & Yates, 1993) in which older adults primarily used the salient cue, emotional valence, and overlooked additional cues that were diagnostic of memory. We hypothesized that age differences in metamemory for emotional words may be eliminated when older adults have a second salient and diagnostic cue to inform judgments of learning (JOLs). We manipulated multiple cues, emotional valence and endorsement (Craik & Tulving, 1975), using a category inclusion task in which participants responded "yes" or "no" to endorse positive words (e.g. "champion") or neutral words (e.g. "sphere") as category members (e.g. "is an achievement"). Age comparisons in free recall and JOL magnitude between levels of emotional valence (positive, neutral) and levels of endorsement (yes, no) indicate that both younger and older adults' JOL magnitudes responded to emotional valence and endorsement effects in which memory was higher for positive than neutral words, and "yes" versus "no" words. JOL accuracy results demonstrate that both age groups' JOLs were significantly accurate above chance within each level of valence and endorsement. Age comparisons in JOL accuracy suggest that including a second salient cue eliminated previously reported age differences in metamemory for positive and neutral words. These results demonstrate that older adults can use multiple cues to make accurate JOLs in the presence of a salient cue. This finding supports a conclusion that previously reported age differences in metamemory for emotional words can be attributed to cue overshadowing effects that diminished older adults' ability to use multiple cues. This conclusion has implications on the aging and metamemory literature such that additional age differences reported in episodic metamemory may also be attributed to conditions that hindered multiple cue use by older adults.
102

The Relationship Between Physical Activity and the Social Network in Older Adults

Thuma, Emily Elise 07 August 2014 (has links)
No description available.
103

Mental health, life periods and physical health correlates, a study of American society

timilsina, kailash 11 October 2013 (has links)
No description available.
104

An existential-phenomenological exploration of an end-of-life doula

Trzeciak-Kerr, M. M. 09 April 2016 (has links)
<p> The purpose of this study was to record and analyze how an end-of-life (EOL) doula and EOL doula care-recipient&rsquo;s [doulee&rsquo;s] family members perceive and describe their personal doula lived experiences during their participation in an EOL doula program. Additionally, it sought to gain clarity on how an EOL doula can augment current palliative and hospice care services to improve and more accurately meet the needs and wants identified by the EOL doulees as reported by the EOL doulee&rsquo;s family members and the EOL doulas that accompanied them. To accomplish this, 15 co-researchers, 11 EOL doulas and 4 doulee family members, from JFCS, Inc. were interviewed wherein they shared their personal doula lived experiences. </p><p> The interviews were analyzed through existential-phenomenological thematic analysis and generated 10 major themes: (a) Just being there, being present, and spending time; (b) No one should die alone; (c) It is important to be a good listener; (d) An EOL doula can work together with hospice because his or her role is different; (e) An EOL doula can provide spiritual support; (f) An EOL doula needs to have certain personality traits; (g) An EOL doula remains open to engage in activities wanted or needed by the EOL doulee; (h) An EOL doula needs to be aware of his or her comfort level with the different phases of dying; (i) An EOL doula can also provide support to the EOL doulee&rsquo;s family and loved ones; and (j) The EOL doula program has comprehensive and ongoing trainings and supervision for all EOL doulas.</p>
105

The relationship between basal cortisol levels and cognitive functioning across the adult lifespan

Saelzler, Ursula 27 May 2016 (has links)
Age-related declines in cognitive functioning have been well documented, however, there are vast individual differences in the age of onset and magnitude of these changes. This observation has spurred the investigation of the potential risk factors for cognitive decline. Chronic elevations of the steroid hormone cortisol have been shown to compromise hippocampal- and frontal cortex- dependent cognitive tasks in rodents, non-human primates and Cushing’s disease patients. Several studies have extended these findings to investigate possible associations between cortisol and cognition in aging human populations. However, these previous examinations of the role of cortisol in cognitive aging have been hampered by the predominant use of single time-point measures of cortisol, small sample sizes, limited age ranges and/or constrained cognitive testing batteries. The present cross-sectional study investigated the relationship between basal cortisol levels, indexed by a 24-hr free cortisol to creatinine ratio, and cognitive functioning on twelve cognitive outcomes in a sample of 1,853 non-demented adults aged 18 to 93 years. The results showed that elevated cortisol levels had small but significant negative effects on verbal learning and working memory performance across the lifespan and significant negative effects limited to older age on a measure of speeded processing. Longitudinal investigation is warranted to examine if within-person changes in cortisol level predict cognitive change.
106

Omega-3 fatty acids to combat sarcopenia

Lalia, Antigoni 15 June 2016 (has links)
<p> <b>Background:</b> Age-related sarcopenia leads to frailty, physical disability and loss of independence. Although exercise is an effective strategy to counteract the prevailing loss of muscle mass, older adults exhibit blunted anabolic responses, and are often unable to adopt an active lifestyle due to comorbidities associated with aging. Long chain polyunsaturated fatty acids (n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid, are non-pharmaceutical nutrients which have surfaced for their potential anabolic properties on skeletal muscle and may be particularly beneficial in the context of sarcopenia. </p><p> <b>Objective:</b> First, to determine if EPA and DHA increase muscle protein synthesis in older adults. Second, to determine if n-3 PUFA increase the anabolic response to an acute resistance exercise stimulus in older adults. Third, to assess if their effect is mediated through improved mitochondrial function, which is known to be impaired with aging. </p><p> <b>Methods:</b> Twelve old, sedentary, healthy women and men (65-85 years) were given 3.9 grams/day purified EPA/DHA for 4 months. 12 young adults (18-35 years) were included as a comparison group for baseline measurements. Muscle protein fractional synthesis rate (FSR) was measured before and after treatment for mixed muscle, and subcellular fractions of myofibrillar, mitochondrial and sarcoplasmic proteins. We infused a stable isotope tracer of [ring-<sup> 13</sup>C<sub>6</sub>] phenylalanine and monitored incorporation of the amino acid into muscle proteins, at the fasting, post absorptive state, and 16 hours following an acute bout of unaccustomed resistance exercise, using mass spectrometry. Muscle mitochondrial function was assessed <i>ex vivo </i> from skeletal muscle biopsies. Further mechanistic information was generated through large scale and individual mRNA gene expression, inflammatory markers, and protein phosphorylation signaling of the anabolic pathway. </p><p> <b>Results:</b> Protein synthesis was similar between age groups at baseline and post exercise, despite the robust decline in mRNA gene expression with aging. EPA/DHA supplementation increased total lean mass, and increased mitochondrial and sarcoplasmic FSR at baseline. Following acute exercise, mixed muscle and subcellular FSR did not change significantly, but participants were segregated into responders and non-responders. EPA/DHA further potentiated the anabolic response of mitochondrial FSR to levels greater than that in the young. There was no improvement in mitochondrial oxidative capacity and efficiency, but there was a significant decrease in ROS emissions. </p><p> <b>Conclusion:</b> In healthy older adults, EPA/DHA exhibited significant anabolic effect in baseline skeletal muscle mitochondrial and sarcoplasmic FSR, which was dissociated from mitochondrial oxidative capacity. The anabolic response to exercise was variable between responders and non-responders where some individuals presented with marked increase in mixed muscle and subcellular FSR. This observation sets the ground for identifying the phenotypic traits of the elderly who are likely to benefit from the therapeutic use of n-3 PUFA to combat sarcopenia of aging.</p>
107

The association between physical activity, sitting time, and chronic disease in the Women's Health Initiative

Gorczyca, Anna M. 04 June 2016 (has links)
<p> Background: Data related to change in physical activity (PA) and sitting time (ST) and the association with mortality after first myocardial infarction (MI) in postmenopausal women are incomplete. A majority of the studies looking at sitting time and colorectal cancer (CRC) did not include physical activity as a potential confounder which is a significant limitation. We investigated the association between change in physical activity and sitting time among survivors of a first MI and all-cause, coronary heart disease (CHD), and cardiovascular disease mortality as well as the independent and joint associations of sitting time and physical activity with risk of incident colorectal cancer in postmenopausal women enrolled in the Women&rsquo;s Health Initiative Observational Study. </p><p> <i>Methods:</i> The WHI-OS cohort included 93,676 postmenopausal women, 50-79 years of age, enrolled between 1993 and 1998. Self-reported ST was reported at baseline, year 3 and year 6. Self-reported PA was reported at baseline and every year thereafter. All-cause, CHD and CVD mortality as well as incident colorectal cancer were the primary outcomes. Cox proportional hazard models were used to estimate hazard ratios and 95% confidence intervals. </p><p> <i>Results:</i> Over a 13-year follow-up, 838 had a clinical MI during follow-up and adequate data on exposures. The risk of all-cause mortality was: 0.43 (0.28-0.70) for the increased activity group and 0.54 (0.38-0.76) for the active, no change group. Women who had pre-MI levels of sitting time &lt; 8 hrs/d had an 11% increased risk (HR= 1.11, 95% CI: 1.01, 1.23) of all-cause mortality for every 1 hr/d increase in sitting time. In the CRC analysis, 74,870 participants were included. Inactivity (&le; 1.7 MET-hrs/wk) was associated with increased risk of rectal cancer and marginally significant increase in CRC (HR=2.23, 95% CI: 1.32 &ndash; 3.79) and (HR=1.20, 95% CI: 0.98 &ndash; 1.48), respectively. </p><p> <i>Conclusions:</i> In conclusion, our findings support the hypothesis that meeting the recommended physical activity guidelines pre- and post-MI has a protective role against mortality in postmenopausal women. Also increased sitting time post-MI was associated with an increased risk of all-cause mortality. Lack of PA was associated with increased risk of rectal cancer and marginally significant increase in CRC.</p>
108

The relationships between sleep disturbance and falls among Veterans who have experienced strokes

Knechel, Nancy Alice 17 February 2016 (has links)
<p> Falls result in more than 2.4 million injuries each year and are the most common adverse events after a stroke. Sleep disturbance is common after stroke and may be a risk factor for falls. The purpose of this study was to determine the predictive value of sleep disturbance for falls among Veterans who experienced ischemic strokes. The study was a secondary analysis of the data from the Diagnosis and <u>T</u>reatment <u>of </u><u>Sleep</u> Apnea in Cerebrovascular Disease (GoToSleep) Study, a longitudinal multi-site randomized controlled strategy trial. The sample included 187 post-stroke Veterans, with a mean age of 70 years, which was predominately male (96.8%) and White (81.3%). The mean Charlson Comorbidity Index score was 2.5, and mean number of comorbid conditions was 6.3. The sample did not have significant stroke-related disability (NIHSS <i> M</i>= 1.9), or physical dependence (Modified Rankin Scale <i>M </i>= 1.0) Data included PSG, medical record review, questionnaires (Epworth Sleepiness Scale, Berlin, Saint Louis University Mental Status), and self-reported falls and injuries. Seventy-two participants had CPAP treatment. Univariate frequency distributions with summary statistics for central tendency and variability, t-tests, Chi-square tests, Fisher's Exact tests, Pearson correlations, and binary and multivariate logistic regression analyses were conducted. Fallers had shorter sleep duration, more frequent awakenings, longer time in bed, more N1 sleep, more spontaneous arousals and respiratory-event related arousals (RERAs), and Periodic Limb Movements (PLMs) per hour than non-fallers. Only the associations between frequency of awakenings per hour and PLM index and falls remained statistically significant in the fully adjusted multivariate model that accounted for approximately 13% of variance beyond the clinical and demographic variables. The odds of a fall increased by 40% for each awakening and 2% for each PLM per hour. After controlling for use of continuous positive airway pressure (CPAP) treatment among the patients with significant sleep apnea, the effects of the sleep variables were not statistically significant. This suggests that treatment of sleep disordered breathing may reduce the odds of falling. Future research is needed to improve confirm and extend these findings, understand the biobehavioral mechanisms for these relationships, and to evaluate the effects of sleep treatment on falls risk.</p>
109

Aging and task representation updating

Frank, David J. 08 October 2015 (has links)
<p>FRANK, DAVID J., Ph.D. Aging and Task Representation Updating. (2015) Directed by Dr. Dayna R. Touron. 96 pp. Older adults? performance decrements can sometime be traced back to inferior strategic choices compared to their younger counterparts. Additionally, older adults often fail to revise their strategic choices with task experience (Bieman-Copland & Charness, 1994; Brigham & Pressley, 1988; Lovett & Schunn, 1999; Price, Dunlosky, & Hertzog, 2008; Touron & Hertzog, 2004a, 2004b; Touron, Hoyer, & Cerella, 2004). Metacognitive models of strategy selection suggests that beliefs, prior knowledge, goals, and task representation influence strategic decisions (e.g., Winne & Hadwin, 1998). No studies to date have attempted to compare task representation in older and younger adults to determine whether older adults? poor strategic choices might be driven by an impoverished understanding of the tasks they are asked to engage in. In two studies we used a pathfinder methodology to elicit conceptual knowledge about a novel chemistry task. In both studies, more conceptual knowledge was related to superior task performance in both younger and older adults. However, we found no evidence of age-related deficits in task representation, formation, or utilization. Surprisingly, participants? task representation scores did not improve following task practice. However, performance improved over trials, even for items that had to be learned with task practice, suggesting that task representation updating did occur. These findings provide indirect evidence of task representation updating in both younger and older adults. However, no age deficits in the ability to update task representations were found. Exploratory analyses suggest that performance in younger adults was related to motivational issues, whereas performance in older adults was driven by higher levels of processing speed and crystallized intelligence.
110

Cutaneous and cerebral microvascular response to the ingestion of flavanols in young and older humans : role of nitric oxide

Harrison, Michelle Lorraine 25 September 2014 (has links)
These studies explored interactions between flavanols and nitric oxide in order to investigate implications for vascular health. Study 1 investigated acute effects of flavanol consumption on cutaneous microvascular endothelial function in young and older individuals along with chronic exposure in older individuals. This was accomplished by assessing skin blood flow response to local heating (thermal reactivity, TR); skin was clamped at 34°C and 40°C and values were normalized to those attained at 43°C. Older individuals demonstrated an attenuated TR at baseline during the entire local heating phase (58.4 ± 2.5% versus 49.3 ± 2.6%, p<0.05). Acutely following flavanol ingestion there was a significant increase in TR (52.4 ± 2.1% versus 56.1 ± 2.0%, p=0.05) that was not different with age. There was no effect of chronic flavanol exposure on TR in older individuals; however, there was a significant decrease in mean arterial pressure (95 ± 3 mmHg versus 91 ± 3 mmHg, p<0.001). These results contribute to research regarding flavanols increasing NO bioavailability; acutely via an improvement in cutaneous microvascular endothelial function and chronically via a reduction in blood pressure. Study 2 investigated the acute effects of flavanol consumption on cerebrovascular endothelial function in young and older individuals along with chronic flavanol exposure in older individuals. This was accomplished by assessing basal cerebral blood flow indices (cerebral vascular conductance index, CVCi) and CBF response to hypercapnia (cerebral vasomotor reactivity; CVMR). At baseline older individuals demonstrated a reduced CVCi (0.85 ± 0.04 cm/s*mmHg versus 0.55 ± 0.04 cm/s*mmHg p=0.001) and CVMR (8.6 ± 0.6 versus 6.9 ± 0.4, p=0.05). An unexpected finding was that flavanol ingestion led to an acute decrease in CVCi (0.71 ± 0.04 cm/s*mmHg versus 0.62 ± 0.04 cm/s*mmHg p<0.05) and CVMR (8.6 ± 0.6 versus 6.1 ± 0.5, p=0.001) that was not different with age. In older individuals, chronic exposure led to a significant increase in CVCi (0.60 ± 0.05 cm/s*mmHg versus 0.72 ± 0.06 cm/s*mmHg, p<0.05) but had no effect on CVMR. These data provide evidence for an improvement in cerebral hemodynamics following chronic exposure in older individuals. / text

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