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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.
51

Wild Embrace

Hatch, Timothy 01 June 2016 (has links)
WILD EMBRACE is a collection of poetry that explores the themes of abuse, survival, and fragility. The speaker of these poems, older and distanced from the abuse, asks what it means to be a survivor, and explores our obligation of compassion that, as human beings, we owe one another. While much of the work in this collection is rooted in personal experience, it is not intended to be read as memoir or autobiography. Many of these poems may have begun as lived experience, but between memory, the transcription of memory, and their final form on the printed page, they have been run through a variety of embellishment, artistic license, and shifting narrative forms. The poems in this collection attempt to capture a heightened emotional truth that can’t be attained by mere reporting of fact. WILD EMBRACE sifts through the ashes of suffering and loss, and constructs a mythology as personal as it is collective.
52

To Find a Stairwell

Porter, Cait 01 January 2019 (has links)
To Find a Stairwell is an exploration and written supplement to my painted works and how it relates to loss, depression, and compulsive tendencies. Through examples of my own paintings and the research and influences leading my education is an articulate web chronicling two years of work from a focus in abstract painting to a place where representation and abstraction intersect.
53

Steuern in Fragilen Staaten : Empfehlungen für die Entwicklungszusammenarbeit

Petersen, Hans-Georg January 2010 (has links)
Fragile states are characterized by institutions which do not have the political will or ability to reduce poverty in the interests of their citizen, to establish basic social security, to promote a successful development process, and to guarantee security and human rights. The regional disintegration processes after the period of imperialism and the fall of the iron curtain have created many new states, which still are politically unstable and unable for a sustainable development. In the literature such states are describes as "weak", "failing or failed", "collapsed", "conflict or post-conflict" - dependant on the extent of the particular state failure. Several indicators try to describe such states and partly allow for projections of the future development. Then the role of taxation is discussed in detail before recommendations for the development cooperation are presented. Obviously taxation plays a key role for the democratization process in fragile states.
54

Diversity and Ecosystem Functioning : Redundancy and Resilience in Freshwater Bacterial Communities

Peter, Hannes January 2011 (has links)
Bacteria are immensely diverse and hold key-positions in essentially all biogeochemical cycles. In freshwater ecosystems, bacteria degrade and mineralize organic compounds, linking the pool of dissolved organic matter to higher trophic levels. Aware of the global biodiversity loss, ecologists have started identifying the relationship of diversity and ecosystem functioning. Central to this is the question if species can functionally replace other species, hence being functionally redundant. Functional redundancy might allow communities to maintain functioning when diversity is lost. Due to their large numbers and great diversity, bacterial communities have been suspected to harbor large amounts of redundancy. The central aim of this thesis is to investigate the coupling of diversity and ecosystem functioning of bacterial communities and to understand how environmental perturbation affects this relationship. I manipulated the diversity of complex communities by a dilution technique, and measured the performance of bacterioplankton and biofilm-forming communities at different diversities. Reduction of bacterial diversity differently affected different functions, and that the presence or absence of certain species might be causing this pattern. However, for ecosystems to function, the interplay of multiple functions, i.e. multifunctionality, has to be sustained over long periods of time. In bacterial biofilm communities reduced diversity affected multifunctionality, as reflected by extracellular enzyme activities. A continuous cultivation system was used to address the importance of diversity for resistance and resilience upon environmental perturbation. The analysis of co-occurrence of bacterial taxa showed that the communities form a dense network before the perturbation and that these patterns are disturbed by the environmental perturbation. The final chapter of the thesis presents experimental evidence for the positive effects of temporal and spatial refuges for bacterial communities and the functions they provide. Overall, I found several indications for a lower amount of functional redundancy as previously assumed and it becomes apparent from this thesis that a multifunctional perspective and the consideration of environmental heterogeneity is pivotal.
55

Seismic Response And Vulnerability Assessment Of Tunnels:a Case Study On Bolu Tunnels

Ucer, Serkan 01 September 2012 (has links) (PDF)
The aim of the study is to develop new analytical fragility curves for the vulnerability assessment of tunnels based on actual damage data of tunnels obtained from past earthquakes. For this purpose, additional important damage data belonging to Bolu Tunnels, Turkey was utilized as a case study. Bolu Tunnels constitute a very interesting case from the earthquake hazard point of view, since two major earthquakes, 17 August 1999 Marmara and 12 November 1999 D&uuml / zce, occurred during the construction of the tunnels. The August 17, 1999 earthquake was reported to have had minimal impact on the Bolu Tunnels. However, the November 12, 1999 earthquake caused some sections of both tunnels to collapse. The remaining sections of the tunnels survived with various damage states which were subsequently documented in detail. This valuable damage data was thoroughly utilized in this study. To develop analytical fragility curves, the methodology described by Argyroudis et al. (2007) was followed. Seismic response of the Tunnels was assessed using analytical, pseudo-static and full-dynamic approaches. In this way, it was possible to make comparisons regarding the dynamic analysis methods of tunnels to predict the seismically induced damage. Compared to the pseudo-static and full-dynamic methods, the predictive capability of the analytical method is found to be relatively low due to limitations inherent to this method. The pseudo-static and full-dynamic solution results attained appear to be closer to each other and better represented the recorded damage states in general. Still, however, the predictive capability of the pseudo-static approach was observed to be limited for particular cases with reference to the full-dynamic method, especially for the sections with increasingly difficult ground conditions. The final goal of this study is the improvement of damage indexes corresponding to the defined damage states which were proposed by Argyroudis et al. (2005) based on the previous experience of damages in tunnels and engineering judgment. These damage indexes were modified in accordance with the findings from the dynamic analyses and actual damage data documented from Bolu Tunnels following the D&uuml / zce earthquake. Three damage states were utilized to quantify the damage in this study.
56

Fragility fractures in fragile people : epidemiology of the age quake

Bergström, Ulrica January 2009 (has links)
Osteoporosis-related fracture is already today a major public health problem and the number of hip fractures is expected to double to 2030. Sweden has one of the highest hip fracture incidences worldwide. This may be explained by several factors: e.g. age, genetic, climatologic, geographic and a relative vitamin D deficiency, secondary to the limited sunlight exposure especially during winter months. Intrinsic and extrinsic factors contribute to a fracture, although a prior low energy fracture is one of the strongest predictors for a subsequent one and this should be a target for secondary fracture prevention in an orthopaedic setting. Since 1993 all injured patients admitted to the emergency floor and all in-hospital fractures at Umeå University Hospital, Sweden, were registered according to the Injury Data Base, former EHLASS. There were 31,173 fracture events (one or more fractures at the same time), of which 13,931 were in patients’ ≥ 50 years old. The fracture database was co analyzed with the Northern Sweden Health and Disease Study cohort in a nested case-control study for investigations of associations between osteoporotic fracture and serum markers, lifestyle data, nutrition etc. We found that there were differences in fracture pattern depending on age and sex. Both injury mechanism and fracture site were strongly dependent of age. The most severe fragility fracture, hip fracture, had a decreasing incidence. However, the incidence curve was right-shifting leading to an increase, both in numbers and in incidence of hip fractures among the oldest female. To identify people at high risk for fractures, re-fracture patients are useful. No less than 21% of the fracture patients had suffered more than one fracture event, accounting for 38% of all fracture events. The total risk ratio for a subsequent fracture was 2.2 (2.1-2.3 95% CI). In males the highest risk for re fracture was in the age cohort 70-79 years (RR 2.7, 2.3-3.2 95% CI), in females > 90 years (RR 3.9, 3.2-4.8 95% CI). Another possible risk factor in this subarctic population is the lack of sunlight, leading to a vitamin D deficit. The overall adjusted risk of sustaining a hip fracture in this population was 2.7 (95%CI:1.3-5.4) in subjects with a serum 25 hydroxyvitamin D below 50 nmol/l. The association was, however, different according to age at baseline. Thus in subjects aged 60 years and above at baseline, the adjusted odds ratio of sustaining a hip fracture was 6.2 (1.2-32.5 95%CI) for the group of individuals with a serum 25OHD below 50 nmol/l, whereas no significant association was found in the youngest age group. In the next 30 years the ongoing demographic changes will accelerate. The World War II baby boomers will cause an age quake. We can already see signs heralding a new fracture pattern: an increasing cohort of mobile but fragile elderly, with considerable co-morbidity is now at risk for fragility fractures. In fracture patients, clinical information is sufficient to pinpoint patients with a high risk for re-fractures. It is therefore clinically important to use the information provided by the fracture event. We suggest that trauma units and primary care units should screen for risk factors and inform patients about the treatment options, and to organize fracture liaison services. This seems to be especially cost-efficient for our oldest and frailest patients. Secondary prophylaxis and follow-up treatment after cardiovascular disorders are now a matter of course worldwide, but the screening for risk factors, in order to prevent a second fracture, is often neglected. This is one of the most important issues of fracture care in the future in order to improve general health.
57

Physical activity, bone density, and fragility fractures in women

Englund, Undis January 2009 (has links)
Scandinavia has among the highest incidence of fragility fractures in the world. The reasons for this are unknown, but might involve differences in genetic and/or environmental factors, such as sunlight exposure and levels of physical activity. Weight-bearing exercise is thought to have a beneficial effect on bone health in the young, but few studies have evaluated whether exercise in older subjects affects bone density and protects against fragility fractures. The initial objective of this thesis was to evaluate whether a combined weight-bearing training programme twice a week would be beneficial as regards bone mineral density (BMD) and neuromuscular function in older women. Forty-eight community living women with a mean age of 73 years were recruited for this 12-month prospective, randomised controlled trial, and were randomly assigned to an intervention group (n=24) or a control group (n=24). The intervention group displayed significant increments in BMD at the Ward’s triangle, maximum walking speed, and isometric grip strength compared to the control group. The second objective was to investigate if training effects were retained in older women five years after the cessation of training. The 40 women who completed the first study included in this thesis were invited to take part in a follow-up assessment five years later, and 34 women (~79 years) agreed to participate. During these five years both groups had sustained significant losses in hip BMD and in all neuromuscular function tests, and the previous exercise-induced intergroup differences were no longer seen. The third and fourth objective of this thesis was to investigate whether exercise and weight-bearing leisure activities in middle-aged women are associated with a decreased risk of sustaining hip or wrist fractures at a later stage. A cohort of women participating in the Umeå Fracture and Osteoporosis (UFO) study, a longitudinal, nested case-control study investigating associations between bone markers, lifestyle, and osteoporotic fractures, was used for the purpose of this investigation. Eighty-one hip fracture cases and 376 wrist fracture cases, which had reported lifestyle data before they sustained their fracture, were identified. These cases were compared with age-matched controls identified from the same cohort. Using conditional logistic regression analysis with adjustments for height, BMI, smoking, and menopausal status, results showed that moderate frequency of leisure physical activities such as gardening and berry/mushroom picking, were associated with reduced hip fracture risk (OR 0.28; 95% CI 0.12 – 0.67), whereas active commuting (especially walking) along with dancing and snow shoveling in leisure time, reduced the wrist fracture risk (OR 0.48; 95% CI 0.27 – 0.88, OR 0.42; 95% CI 0.22 – 0.80 and OR 0.50; 95% CI 0.32 – 0.79 respectively). In summary, this thesis suggests that weight-bearing physical activity is beneficial for BMD and neuromuscular functions such as muscle strength and gait in older women, and that a physically active lifestyle, with outdoor activities, in middle age is associated with reduced risk of both hip and wrist fractures. Possible mechanisms underlying this association include improved muscle strength, coordination, and balance, resulting in a decreased risk of falling and perhaps also direct skeletal benefits.
58

Nuovi genitori e fragilità relazionali. Riflessioni pedagogiche e prospettive d'intervento.

MALTESE, GIUSTINA 05 March 2012 (has links)
La ricerca mira ad individuare alcune fragilità relazionali ed educative che sembrano contraddistinguere i “nuovi” genitori, oggi, in modo da tentare di formulare adeguate strategie pedagogico-educative d’intervento. Per il raggiungimento di tale obiettivo, si è proceduto, inizialmente, con l’analisi delle trasformazioni socio-culturali che hanno investito la nostra società. Ciò ha permesso di individuare ed esaminare due categorie: quella sociologica della “vulnerabilità” e quella pedagogica della “fragilità”. Successivamente, per meglio comprendere le fragilità educative e relazionali vissute dai “nuovi” genitori, si è ritenuto indispensabile procedere con la somministrazione di un questionario rivolto ai genitori con figli in età prescolare (0-3 anni). / The aim and objective of my research is to identify some relational and educational fragility of the “new” parents. Moreover, I would like to formulate appropriate strategies for pedagogical and educational intervention. To achieve that aim I have identified and investigated two categories: the sociological category of “vulnerability” and the pedagogical category of “fragility”. In order to better understand this educational and relational fragility. I have proceed with the administration of a questionnaire. This questionnaire is directed to parents with sons in preschool age (0-3 years).
59

Dynamics in orientationally disordered solids

Martínez García, Julio César 15 July 2011 (has links)
The key features of dynamics of ultraslowing glass forming systems are their universality in diversity. Its origin is recognized as one of the greatest challenges of condensed matter physics and materials engineering in the XXI century. Similar phenomena are observed on approaching the glass transition in low molecular weight supercooled liquids, polymers, colloidal fluids as well as in solids, for instance in orientationally disordered crystals, spin glass-like magnetic, vortex glasses. Pre-vitreous dynamics is also proposed as a general reference for the category of complex liquids/soft matter systems. The upsurge of the primary relaxation time or related dynamical properties is the basic physical phenomena of the still mysterious previtreous behavior. This means a much more pronounced slowing down than the Arrhenius pattern observed far above the glass transition temperature. Portraying this behavior constitutes one of key checkpoints for theoretical models developed to unwind the glass transition puzzle. However, none of the aforementioned features can answer the understanding that governs the increase of relaxation time in liquids upon cooling. In this thesis we focus on the above questions studying the dynamics of some materials for which their molecules can retain a translational order being orientationally disordered between them upon cooling, which are referred to plastic phases or orientationally disordered (OD) crystalline phases. The work presented in this thesis potentially extends the knowledge of dynamics of OD phases and orientationally glasses (OG), a research topic which has gained interest during the last decades. Through this study, especial attention has been devoted to the phenomenological equations accounting to the temperature dependence of the mean relaxation time describing the orientational dynamics .The study was carried out by the use of BDS as well as two complementary experimental techniques. We show distortion-sensitive and derivative-based empirical analysis of the validity of leading equations for portraying the previtreous evolution of primary relaxation time. A new method for studying the dynamics of glass forming systems is introduced and the minimization procedure is validated and discussed. We present the results divided in two topics, the dynamics of the pure compounds and mixed crystals and the derivative analysis through different existing models. In the first topic we focus on the dynamics of the pure compounds and mixed crystals formed between cycloheptanol and cyclooctanol as well as the a-relaxation dynamics of 1-cyano-adamantane and its mixtures with 1-chloro-adamantane. The second topic is divided in two groups of models, linearized and non-linearized models. In the linearized models we show the application of the derivative based, distortion-sensitive analysis to liquid crystals (LC) and OD phases. We also discuss the results concerning to the cases of the olygomeric liquid epoxy resin (EPON828), neopentylalcohol and neopentylglycol mixture, isooctylcyanobiphenyl and propylene carbonate. The possible empirical correlations between one of the linearized models with the universal pattern for the high frequency wing of the loss curve for primary relaxation time for LCs and OD phases is also shown. In the final part we show that the form of the equation recently introduced by Mauro et al. does not allow a similar straightforward linearization procedure. Unlike the previous models, the involved parameters are not correlated with the slope and the intercept of a linear function. In order to solve this problem, we have introduced the concept of the enthalpy space. The evidences of the existence of crossovers as well as quantitative descriptions are discussed. We show also a new procedure for detecting the crossover in a very easy way. A new kind of crossovers which seems to be impossible to be detected by the classical Stickel transformation is presented. / La principal característica de la dinámica de sistemas vítreos viscosos, es su universalidad en la diversidad. Su origen es uno de los mayores desafíos de la física de la materia condensada y de la ingeniería de materiales en el siglo XXI. La fenomenología típica de las fases vítreas se observan cerca de la transición vítrea en líquidos subenfriados de bajo peso molecular, polímeros, fluidos coloidales, así como en los sólidos con fases orientacionalmente desordenadas. La imposibilidad de explicar las causas del gran aumento del tiempo de relajación al enfriar un líquido, constituye uno de los problemas más importantes no resueltos en materia condensada. Con el objetivo de dar respuesta a dicha interrogante, se han propuesto modelos termodinámicos y dinámicos que han resultado inconsistentes. En esta tesis nos centramos en dicha problemática, estudiando la dinámica orientacional de algunos materiales que al ser enfriados pueden conservar un orden traslacional mientras que se conserva el desorden orientacional de las moléculas que los forman. Dichas fases se conocen como fases plásticas u orientacionalmente desordenadas (OD). El trabajo presentado en esta tesis amplía el conocimiento de la dinámica de dichas fases, un tema de investigación cuyo interés ha aumentado durante las últimas décadas. Se ha dedicado una atención especial a las ecuaciones fenomenológicas que describen la dependencia del tiempo de relajación con la temperatura. El estudio se ha llevado a cabo mediante el uso de espectroscopía dieléctrica de banda ancha, así como mediante el uso de técnicas experimentales complementarias. Se ha introducido un nuevo método para el estudio de la dinámica de los sistemas que dan lugar a fases vítreas. El método ha sido validado y discutido. Los resultados de esta tesis se presentan divididos en dos temas, por un lado, la dinámica de compuestos puros y de los cristales mixtos y, por otro, el análisis mediante el método derivativo aplicado a los diferentes modelos físicos existentes. En el primer tema nos centramos en la dinámica de los compuestos puros y los cristales mixtos formados por cicloheptanol y ciclooctanol, así como la dinámica de la relajación alfa en 1-ciano-adamantano y sus mezclas con 1-cloro-adamantano. El segundo tema se divide en dos grupos de modelos, los modelos lineales y no lineales. En los modelos lineales se muestra la aplicación del procedimiento de derivativo en los cristales líquidos (CL) y las fases OD. También se discuten los resultados relativos a los casos de la resina líquida (EPON828), la mezcla neopentil-alcohol y neopentil-glicol, el carbonato de propileno, así como el CL isooctilcianobifenil. Se discute también la existencia de posibles correlaciones empíricas entre uno de los modelos lineales con el patrón universal para la parte de alta frecuencia de la curva de pérdidas dieléctricas de la relajación primaria para las fases CL y OD. En la parte final se muestra que la forma de la ecuación introducida recientemente por Mauro et al. no permite la linearización mediante el método derivativo. A diferencia de los modelos anteriores, los diferentes parámetros no están correlacionados con la pendiente y el origen de coordenadas de una función lineal. Para resolver este problema, hemos introducido el concepto del espacio entálpico. Se analiza también la existencia de cambios de comportamiento dinámicos y se aportan descripciones cuantitativas. Se muestra también un nuevo procedimiento para detectar los cambios dinámicos de una manera fácil, que permite incluso detectar aquéllos que son obviados mediante el método clásico de Stickel.
60

Building Seismic Fragilities Using Response Surface Metamodels

Towashiraporn, Peeranan 20 August 2004 (has links)
Building fragility describes the likelihood of damage to a building due to random ground motions. Conventional methods for computing building fragilities are either based on statistical extrapolation of detailed analyses on one or two specific buildings or make use of Monte Carlo simulation with these models. However, the Monte Carlo technique usually requires a relatively large number of simulations in order to obtain a sufficiently reliable estimate of the fragilities, and it quickly becomes impractical to simulate the required thousands of dynamic time-history structural analyses for physics-based analytical models. An alternative approach for carrying out the structural simulation is explored in this work. The use of Response Surface Methodology in connection with the Monte Carlo simulations simplifies the process of fragility computation. More specifically, a response surface is sought to predict the structural response calculated from complex dynamic analyses. Computational cost required in a Monte Carlo simulation will be significantly reduced since the simulation is performed on a polynomial response surface function, rather than a complex dynamic model. The methodology is applied to the fragility computation of an unreinforced masonry (URM) building located in the New Madrid Seismic Zone. Different rehabilitation schemes for this structure are proposed and evaluated through fragility curves. Response surface equations for predicting peak drift are generated and used in the Monte Carlo simulation. Resulting fragility curves show that the URM building is less likely to be damaged from future earthquakes when rehabilitation is properly incorporated. The thesis concludes with a discussion of an extension of the methodology to the problem of computing fragilities for a collection of buildings of interest. Previous approaches have considered uncertainties in material properties, but this research incorporates building parameters such as geometry, stiffness, and strength variabilities as well as nonstructural parameters (age, design code) over an aggregation of buildings in the response surface models. Simulation on the response surface yields the likelihood of damage to a group of buildings under various earthquake intensity levels. This aspect is of interest to governmental agencies or building owners who are responsible for planning proper mitigation measures for collections of buildings.

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