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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.
411

Public engagement in rural aging communities

Denker, Amy E. January 1900 (has links)
Master of Regional and Community Planning / Department of Landscape Architecture/Regional and Community Planning / Katherine Nesse / Public engagement in rural, aging communities is often an after thought when creating plans, strategies, or projects in these communities. Initiatives that focus specifically on interacting with aging ruralites through new media is almost non-existent. However, engagement through web-based forums or social media is a growing trend. At the same time, older people have proven that they do not use the internet or social media as frequently as younger generations. To bridge the gap of inexperience with online forms of engagement, I investigate whether educational components introduced through traditional face-to-face forms of public engagement can increase the participation of older residents. To test this, I introduce social media and online engagement to older adults through an educational presentation at a public meeting in Council Grove, Kansas, in cooperation with the Flint Hills Regional Council. I monitored social media and online websites connected to the public meeting prior to and after the meeting to track changes in engagement that occurred due to the meeting. Though there was little change in engagement on the two websites I monitored, the survey results suggest that the people at the meeting appreciated the introduction and did have some familiarity with the internet and the online engagement environments. Unfortunately, this research does not definitively answer the question asked. It suggests that further education presented in future meetings may increase online engagement when implemented at a larger scale.
412

Factors predicting intraindividual cognitive variability in older adults with different degrees of cognitive integrity

Shoji, Kristy Douglas 20 October 2016 (has links)
<p> Given the increasing number of older adults in the population, the fact that about 1 in 10 people over the age of 65 will develop mild cognitive impairment, and the substantial individual, familial, and financial burden associated with such disorders, the need for innovative research examining cognitive impairment in older adults is evident. The present study used a microlongitudinal design to assess cognition and contextual factors that may affect cognition for 14 consecutive days using a daily diary method in older adults with varying degrees of cognitive function. This study design enables investigation of concurrent associations between variables, as well as providing unique information not gleaned from the traditional focus on mean values of cognition. The present study had two broad aims: 1) to compare variability in cognition in older adults with varying degrees of cognitive impairment and 2) to investigate relationships between daily cognitive performance, variability in cognitive performance, and contextual factors that may influence daily cognitive performance and variability in older adults with varying degrees of cognitive impairment. Results suggest there was sufficient intraindividual variability in daily cognition to warrant investigation of within-person associations. Furthermore, the contextual factors of pain, stress, and sleep were predictive of cognitive performance, but with significance and directionality of these associations depending on level of measurement (baseline, daily, or mean values). Finally, associations between contextual factors and cognition were frequently conditional upon baseline cognitive status. The findings highlight the need for continued examination of these associations to expand our understanding of cognition in older adults and to discover potential targets for interventions to attenuate cognitive decline.</p>
413

Volatility and Chemical Aging of Atmospheric Organic Aerosol

Karnezi, Eleni 01 February 2017 (has links)
Organic particulate matter represents a significant fraction of sub-micrometer atmospheric aerosol mass. However, organic aerosol (OA) consists of thousands of different organic compounds making the simulation of its concentration, chemical evolution, physical and chemical properties extremely challenging. The identity of the great majority of these compounds remains unknown. The volatility of atmospheric OA is one of its most important physical properties since it determines the partitioning of these organic compounds between the gas and particulate phases. The use of lumped compounds with averaged properties is a promising solution for the representation of OA in atmospheric chemical transport models. The two-dimensional volatility basis set (2D-VBS) is a proposed method used to describe OA distribution as a function of the volatility and oxygen content of the corresponding compounds. In the first part of the work we evaluate our ability to measure the OA volatility distribution using a thermodenuder (TD). We use a new method combining forward modeling, introduction of ‘experimental’ error and inverse modeling with error minimization for the interpretation of TD measurements. The OA volatility distribution, its effective vaporization enthalpy, the mass accommodation coefficient and the corresponding uncertainty ranges are calculated. Our results indicate that existing TD-based approaches quite often cannot estimate reliably the OA volatility distribution, leading to large uncertainties, since there are many different combinations of the three properties that can lead to similar thermograms. We propose an improved experimental approach combining TD and isothermal dilution measurements. We evaluate this experimental approach using the same model and show that it is suitable for studies of OA volatility in the lab and the field. Measurements combining a thermodenuder (TD) and a High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) took place during summer and winter in Paris, France as part of the collaborative project MEGAPOLI and during the winter of 2013 in the city of Athens. The above volatility estimation method with the uncertainty estimation algorithm is applied to these datasets in order to estimate the volatility distribution for the organic aerosol (OA) and its components during the two campaigns. The concentrations of the OA components as a function of temperature were measured combining data from the thermodenuder and the aerosol mass spectrometer (AMS) with Positive Matrix Factorization (PMF) analysis. Combining the bulk average O:C ratios and volatility distributions of the various factors, our results are placed into the two-dimensional volatility basis set (2D-VBS) framework. The OA factors cover a broad spectrum of volatilities with no direct link between the average volatility and average O:C of the OA components. An intercomparison among the OA components of both campaigns and their physical properties is also presented. The approach combining thermodenuder and isothermal dilution measurements is tested in smog chamber experiments using OA produced during meat charbroiling. The OA mass fraction remaining is measured as a function of temperature in the TD and as a function of time in the isothermal dilution chamber. These two sets of measurements are used together to estimate the volatility distribution of the OA and its effective vaporization enthalpy and accommodation coefficient. In the isothermal dilution experiments approximately 20% of the OA evaporate within 15 min. In the TD almost all the OA evaporated at approximately 200oC. The resulting volatility distributions suggest that around 60-75% of the cooking OA (COA) at concentrations around 500 μg m-3 consists of low volatility organic compounds (LVOCs), 20-30% of semi-volatile organic compounds (SVOCs) and around 10% of intermediate volatility organic compounds (IVOCs). The estimated effective vaporization enthalpy of COA is 100 ± 20 kJ mol-1 and the effective accommodation coefficient is around 0.05. The characteristics of the COA factor from the Athens campaign are compared to those of the OA produced from meat charbroiling in these experiments. In the next step, different parameterizations of the organic aerosol (OA) formation and evolution in the two-dimensional Volatility Basis Set (2D-VBS) framework are evaluated using ground and airborne measurements collected in the 2012 Pan-European Gas AeroSOls-climate-interaction Study (PEGASOS) field campaign in the Po Valley, Italy. A number of chemical schemes are examined, taking into account various functionalization and fragmentation pathways for biogenic and anthropogenic OA components. Model predictions and measurements, both at the ground and aloft, indicate a relatively oxidized OA with little average diurnal variation. Total OA concentration and O:C ratios were reproduced within experimental error by a number of chemical aging schemes. Anthropogenic SOA is predicted to contribute 15-25% of the total OA, while SOA from intermediate volatility compounds oxidation another 20-35%. Biogenic SOA contributions varied from 15 to 45% depending on the modeling scheme. The average OA and O:C diurnal variation and their vertical profiles showed a surprisingly modest sensitivity to the assumed vaporization enthalpy for all aging schemes. This can be explained by the intricate interplay between the changes in partitioning of the semivolatile compounds and their gas-phase chemical aging reactions. The same set of different parameterizations of the organic aerosol (OA) formation and evolution in the two-dimensional Volatility Basis Set (2D-VBS) framework are evaluated using ground measurements collected in the 2013 PEGASOS field campaign in the boreal forest station of Hyytiälä in Southern Finland. The most successful is the simple functionalization scheme of Murphy et al. (2012) while all seven aging schemes have satisfactory results, consistent with the ground measurements. Despite their differences, these schemes predict similar contributions of the various OA sources and formation pathways. Anthropogenic SOA is predicted to contribute 11- 18% of the total OA, while SOA from intermediate volatility compounds oxidation another 18- 27%. The highest contribution comes from biogenic SOA, as expected contributing 40 to 63% depending on the modeling scheme. The primary OA contributes 4% while the SOA resulting from the oxidation of the evaporated POA varies between 4 to 6%. Finally, 5-6% is according to the model the results of long range transport from outside the modeling domain.
414

Memory for associative integrations depends on emotion and age

Murray, Brendan David January 2013 (has links)
Thesis advisor: Elizabeth A. Kensinger / A key feature of human memory is the ability to remember not only discrete pieces of information but also to form novel associations between them. A special type of association, called an "integration", can be formed when the pieces are encoded as a single representation in memory (Wollen, Weber and Lowry, 1972; Murray and Kensinger, 2012). The work presented here investigates what neural mechanisms underlie the formation and subsequent retrieval of integrated mental images in younger adulthood (individuals aged 18-30), whether those mechanisms differ based on the emotional content of the integration, and whether older and younger adults generate and remember emotional integrations differently from one another. I show that younger adults utilize two different routes to form integrations, depending on their emotional content: a rapid, perceptually-supported route that allows for fast integration of emotional pairs but that leads to poor downstream memory for the associates, and a slow, conceptually-supported route for neutral pairs that takes more time but that leads to strong downstream memory. Conversely, older adults utilize slow, controlled processing of emotional integrations that leads to strong memory, but they fail to produce durable memory for non-emotional pairs due to age-related associative deficits. Together, these results highlight differences both within and between age groups in the formation and retrieval of emotional and non-emotional integrations, and suggest a circumstance - integration of emotional pairs - in which older adults can overcome previously reported age-related deficits. / Thesis (PhD) — Boston College, 2013. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Psychology.
415

The Ties That Bind: An Examination of the Role of Neighborhood Social Networks for Older Adults in Post-Katrina New Orleans, Louisiana

Unknown Date (has links)
Many community-dwelling older adults spend a significant amount of time in their homes, neighborhoods, and nearby areas. Much is known about the effects that the physical environment has on older adults, but comparatively less is known about neighborhood social environments. The neighborhood is an important unit for study because it is a microcosm of greater social processes and smaller interpersonal relationships. This doctoral case study examined the characteristics and functions of social relationships for older adults in three socioeconomically different New Orleans, Louisiana neighborhoods that were differently affected by the 2005 Hurricane Katrina disaster. The study also explored differences between older adult-serving networks across neighborhoods. Older adults comprised a majority of storm-related deaths from Hurricane Katrina. Over a decade post-storm, residential life in the study neighborhoods has entered a new normal, but for older adults, recovery has been difficult. The constant throughout the recovery period has been relationships with family, friends, neighbors, and informal ties in the community. Findings suggest that apart from family and friends, relationships with neighbors and those known from informal community settings serve important supportive and social roles for older adults. Participation with older adult-serving networks enables individuals to stay active, social, and intellectually engaged. Formal networks including senior centers and community organizations operate official programs to meet needs, but engage with participants in an informal manner, thereby increasing participation. Findings reveal that having neighborhood-based community resources empowers older adults to socialize with others, maintain their health and wellness, and remain thriving, productive community members near their homes. These resources promote rich social lives and successful aging in the community. Additionally, special districts and partnerships affect the flow of resources and opportunities into neighborhoods, which influence how different networks in different neighborhoods in this study function. Planners and local governments recognize the neighborhood as an important unit of the community and are empowering them to secure resources and meet needs on a small scale. Policymaking bodies are supporting the community in these endeavors by supporting legislation that empowers neighborhoods to leverage resources to help themselves. These efforts are having significant impacts on the greater community as recovery in these neighborhoods progresses. / A Dissertation submitted to the Department of Urban and Regional Planning in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Spring Semester 2018. / February 26, 2018. / aging, disasters, neighborhood, older adults, social networks, social relationships / Includes bibliographical references. / Jeffrey R. Brown, Professor Directing Dissertation; Jean Munn, University Representative; Rebecca Miles, Committee Member; April Jackson, Committee Member.
416

Meeting the Need: A Cross-Sectoral Assessment of Transportation Alternatives for Suburban Older Adults

Unknown Date (has links)
The percentage of older adults residing in America’s auto-oriented suburbs is projected to grow significantly in the coming decades. When these individuals are no longer able to safely drive themselves, they may seek alternative modes of transportation in order to maintain their independence. In many metro areas, robust public transit exists in the urban core but can be relatively sparse in suburban areas, thus creating a service gap. At the same time, a growing number of elder-service nonprofits have begun to offer transportation services for older clients, leveraging unique staff expertise with elder-care issues in order to fill the service gap. The potential for partnerships between nonprofits and public transit agencies is on the rise, fueled primarily by federal grants and skyrocketing demand for transportation. This dissertation examines the state of affairs in elder-service transportation in the suburbs of three American cities from three perspectives: The elder-service nonprofits innovating programs, the transit agencies partnering with these nonprofits, and the older adults who use these services in order to age in place. The investigation relies on interviews, focus groups, and document analysis as source material. Using a process of axial coding and pattern matching, analysis focuses on the ways in which providers function, partner, and meet the needs of suburban older adults. The results show that these nonprofit innovators are delivering specialized and elder-conscious services that are quite popular with riders, while also often remaining deliberately independent of taxpayer support. Interagency partnerships, although viewed positively by managers in both agency types, are thus limited to short-term contracts that dissipate as the nonprofit matures and secures local funding. Where partnerships do occur, results show a need for simplified reporting of designated outcomes and better information-sharing between agencies. Taken together, the results indicate a rich and varied network of resources being committed to address this critical mobility challenge. / A Dissertation submitted to the Department of Urban and Regional Planning in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Spring Semester 2018. / March 1, 2018. / Nonprofit Management, Older Adults, Partnerships, Rider Perspective, Suburbia, Transportation / Includes bibliographical references. / Jeffrey R. Brown, Professor Directing Dissertation; Ralph S. Brower, University Representative; Rebecca Miles, Committee Member; Michael Duncan, Committee Member.
417

Ageing and the continuity of masculine identity in a Scottish men's shed : an ethnographic enquiry

Watt, Jeremy Charles January 2017 (has links)
No description available.
418

Chronological and biological senescence in wild yellow-bellied marmots (Marmota flaviventer)

Kroeger, Svenja Brigitte January 2017 (has links)
Senescence is an intricate, multifaceted process that can vary among populations, individuals, and traits within individuals. However, the relative importance of factors generating observed differences in senescence patterns remains poorly understood. In particular, there is a lack of studies that quantify both age-dependent and state dependent components of senescence, and do so across different environmental conditions. Also, few studies have explicitly tested cumulative reproductive costs, or how early-life conditions like maternal age and state at offspring birth affect offspring adult phenotypes and senescence trajectories. I use individual-based long-term data from wild yellow-bellied marmots, to quantify chronological (age-dependent) and biological (state-dependent) senescence in female reproductive success and season-specific body mass across two different elevational environments. Since previous reproductive history could influence biological age, I also estimate costs of previous short-term and cumulative long-term reproduction on females' current reproductive success. Finally, I test whether maternal age and state at daughter birth affect daughter reproduction and senescence. I demonstrate complex senescence patterns in body mass and reproductive success. First, senescence in body mass has both age-dependent and state-dependent components, and effects are greater at lower elevation than higher elevation and greater in late summer than in spring. Second, at both elevations, females that reproduced frequently and weaned large litters in previous years have reduced current reproductive probability, while there are no short-term effects of previous reproduction. Finally, higher chronological age and closer proximity to death of the mother have positive environment-dependent effects on daughter reproductive trajectories. Overall, my findings reveal the need to investigate senescence patterns across multiple environments and over long time periods to allow capturing certain intra-individual and inter-generational effects. The persistence of maternal effects into daughters' adult lives highlights the complexity of life-history trade-offs, and calls for more studies that consider such long-term transgenerational effects when studying life-history variation and senescence in wild populations.
419

Muscle aging: identification and characterization of age-related changes in aqueous skeletal muscle proteins. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2001 (has links)
by Cai Dong Qing. / "January 2001." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001 / Includes bibliographical references (p. 179-190). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
420

It's not how old you are but how you are old: A review on aging and consumer behavior

Zniva, Robert, Weitzl, Wolfgang 12 1900 (has links) (PDF)
The paper presents a review of 128 studies on the behavior of older consumers published in the last 35 years (from 1980 to 2014) in 35 peer-reviewed journals. The purpose of the procedure is twofold: First, we aim to summarize results on agerelated changes in consumer research. Second, by doing so, we evaluate the relative importance of age-related factors (chronological, biological, psychological, and social age as wells as life events and life circumstances) in research on older consumers. Results of the review show that research on older consumers is still dominated by investigations using chronological age. Influences of other aspects of the aging process, although recommended by previous research reviews and providing valuable insights, are still playing a minor role in the investigation of consumer behavior. Research with alternative age measures is still in an early, exploratory stage and future studies should include specific aspects as well as multitheoretical models of aging.

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