Since a significantly greater percentage of body weight is supported by the non-paretic limb following stroke, a greater amount of fatigue may be present during daily activities. This may affect the ability of these individuals to maintain a stable upright posture. The presence of falls following a stroke has been attributed in part to this asymmetrical stance post-stroke. Therefore the purpose of this study was to assess the effect of quadriceps muscle fatigue on bi-pedal posture in individuals who had a stroke and an age-matched control group. Although individuals after stroke displayed greater postural sway under the paretic limb than the non-paretic limb or control subjects, results of this study show that sustaining an isometric knee extension of the non-paretic limb induces changes in postural control for individuals after stroke, but that these changes do not markedly differ from those of healthy age-matched controls.

Bakgrund: Fatigue är en biverkan hos kvinnor med bröstcancer som genomgår adjuvantbehandling. Sjuksköterskan kan genom sina omvårdnadsåtgärder hjälpa dessa kvinnor atthantera och minska biverkningar av fatigue. Begreppet empowerment och Orems teori omhjälp till självhjälp kan ses som en grund för sjuksköterskan i detta omvårdnadsarbete.Syfte: Att beskriva hur kvinnor med bröstcancer, under adjuvant behandling, kan hantera ochminska symptomet fatigue med hjälp av sjuksköterskans omvårdnadsinsatser, grundat i begreppet empowerment och hjälp till självhjälp.Metod: Litteraturbaserad studie med grund i tolv kvalitativa och kvantitativa artiklar.Resultat: Förekomsten av fatigue finns kvar men olika metoder kan ge minskade nivåer.Motion och rörelse kan lindra graden av fatigue. Muskelavslappningsövningar gav minskadenivåer och minskad upplevelse av fatigue. En balanserad sömn och minskad stress gavpositiva effekter på upplevd fatigue.Slutsats: Det finns olika omvårdnadsinsatser sjuksköterskan kan genomföra, dels själv menockså tillsammans med andra professioner. Tillsammans med patienten kan sjuksköterskankartlägga graden av fatigue och skräddarsy en individuell omvårdnadsplan. Motionsprogramoch gruppinterventioner med empowerment som grund kan stärka och hjälpa dessa kvinnorhantera fatigue. / Background: Fatigue is a side effect for women with breast cancer undergoing adjuvant therapy. The nurse can through nursing interventions help these women to manage and reduce side effects of fatigue. The concept of empowerment and the Orem theory of self-help can beviewed as a basis for the nurse in nursing. Purpose: To describe how women with breast cancer during adjuvant treatment, manage and reduce symptom of fatigue with the help of nursing care interventions, founded in the concept of empowerment and self-help. Method: Literature-based study based on twelve qualitative and quantitative articles. Results: The incidence of fatigue remains, but different methods can reduce levels. Exercise and movement can alleviate the degree of fatigue. Musclerelaxation exercises resulted in decreased levels and decreased perception of fatigue. A balanced sleep and reduced stress resulted in positive effects on perceived fatigue. Conclusion: There are several of nursing interventions that are possible to implement both for nurses alone and also with other professions. Together can nurses and their patients determine the degree of fatigue and tailor an individual care plan. Exercise program and group interventions with empowerment as a basis can be used to strengthen and help these women manage fatigue.

<p>Fatigue is a common and debilitating symptom for adult patients with end-stage renal disease on hemodialysis and has been associated with decreased survival and quality of life. Patients on hemodialysis must find ways to manage their fatigue and mitigate its effects on their lives. Currently, there is no description of the experience of fatigue for American hemodialysis patients, nor is there any description of the ways in which they manage their fatigue. The purpose of this qualitative descriptive work was to describe the experience and self-management of fatigue as well as how fatigue changes over time from one dialysis session to the next. Several themes were identified which included: the nature of fatigue, cycles of fatigue, management of fatigue, consequences of fatigue, and correlates of fatigue. Further, hemodialysis patients experience two types of fatigue, post-dialysis fatigue, fatigue that occurs acutely after the dialysis session and resolves after sleep or rest, and constant fatigue, a persistent, underlying fatigue that patients experience at all times and worsens after the dialysis session usually requiring a prolonged period of recovery.</p> / Dissertation

Atherosclerotic plaque caps are composed of a composite soft tissue material that becomes subjected to cyclic loading under stenotic flow conditions. The cyclic loading causes the plaque cap to fatigue and eventually fail. The hypothesis of this work is that arteries and plaque caps may fatigue which may be predicted by a stress vs. number of cycles (S-N) curve. The S-N curve has not been determined for almost any biological soft tissue. The Specific Aim of the thesis is to quantify an S-N curve for normal arterial soft tissue collected from cyclic tension testing. Coronary arteries from porcine hearts will be tested as a material that closely models the plaque cap in non-linear elastic behavior. The S-N curve will be developed through failure testing with multiple cycles at stresses between 0.5 and 5 MPa.

Fatigue cracking is one of the primary modes of distress in asphalt pavements that has an important economic impact. Fatigue resistance characterization of an asphalt mixture is a complex issue due to: (i) composite nature of the material, (ii) gradation of aggregate particles, (iii) variation of asphalt film thickness, (iv) air voids distributions, (v) asphalt binder nonlinear viscoelastic behavior, (vi) effects of binder oxidative aging as a function of time, and (vii) micro crack healing during rest periods. Different methods to assess fatigue cracking in asphalt materials are available in the literature. However, there is no methodology to characterize fatigue cracking behavior of asphalt materials that is independent of the mode of loading (controlled-strain or controlled-stress). The objective of this research is to develop a new methodology to characterize fatigue cracking of the fine aggregate matrix (FAM) portion of asphalt mixtures using dynamic mechanical analyses (DMA). This is accomplished through different, but related, approaches. The first approach relies on identifying the various mechanisms of energy dissipation during fatigue cracking that are manifested in: (i) nonlinear viscoelastic deformation, (ii) fracture, and (iii) permanent deformation. Energy indices were derived to quantify each of these energy dissipation mechanisms and to quantify fatigue cracking irrespective of the mode of loading. The first outcome of the approach is a fatigue damage parameter (crack growth index) that provides comparable results for a given material even when tested under different modes of loading and different load (strain or stress) amplitudes. The developed fatigue characterization method has a lower coefficient of variation when compared to conventional parameters (number of load cycles to failure or cumulative dissipated energy). The crack growth index parameter was also qualitatively and quantitatively compared to three dissipated energy methods available in the literature. The second outcome of this research is a constitutive model that can describe both asphalt mixtures’ nonlinear viscoelastic response and fatigue damage in one formulation. Nonlinear viscoelastic as well as damage parameters were obtained for both modes of loading. This second approach has the advantage that the constitutive model can be implemented in a numerical framework to describe the response of asphalt mixtures under various boundary conditions.

The dislocation structure evolution of polycrystalline copper at constant strain amplitude during low cycle fatigue develops loop patches, vein structure, persistent slip bands, dislocation walls, dislocation cells, and cells with misorientation dislocation step-by-step by increasing fatigue cycles. However, the dislocation structure evolution will change in low cycle fatigue under reduced loading amplitude. The polycrystalline copper of 99.99 at% purity and 60&#x00B5;m in grain size was used in the low cycle fatigue test. First, the test is controlled at £G£`/2= ¡Ó0.4%, ¡Ó0.2%, and ¡Ó0.1% strain amplitude until the specimens crack. And control the fatigue test after 2500 cycles at ¡Ó0.4% strain amplitude. Then we can observe the dislocation structure of above specimens by electron microscope. After 2500 cycles at ¡Ó0.4% strain amplitude, change the strain amplitude from ¡Ó0.4% to ¡Ó0.2%. We chose the steps of low cycle fatigue test under reduced loading amplitude at 1000, 10000, and 30000 cycles. By the same token, change the strain amplitude from ¡Ó0.4% to ¡Ó0.2%. We chose the steps of low cycle fatigue test under reduced loading amplitude at 1000, and 50000 cycles. Then observe the dislocation structure of above specimens by electron microscope, and we can know the dislocation morphology of evolution process under reduced loading amplitude. After 2500 cycles at ¡Ó0.4% strain amplitude, change the strain amplitude from ¡Ó0.4% to ¡Ó0.2% and from ¡Ó0.4% to ¡Ó0.1%. After 1000 cycles, the dislocation wall can be observed at grain boundary. After 10000 cycles under changed loading amplitude from ¡Ó0.4% to ¡Ó0.2%, we can observe that the dislocation cells are broken and evolve loop patches. And after 50000 cycles under changed loading amplitude from ¡Ó0.4% to ¡Ó0.1%, large area of dislocation walls and some loop patches can be observed.

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Abstract The thesis is aimed to simulate the flip chip in chip scale package (FCCSP) by finite element method incorporated with software ANSYS due to thermally cyclic loading. The difference between two-dimensional and tree-dimensional structures is conferred. The position and height of solder bump in FCCSP and cyclic temperature are considered as parameters. The effects of above-mentioned parameters on package¡¦s fatigue models and fatigue damage are studied. The results show that the two-dimensional structure can help us to understand the position of the maximum displacement and the maximum equivalent strain. However, the values of numerical result in the two- dimensional structure are not very accurate. The fatigue fracture will first take place at the top of the most outside solder bump far away from the center of the whole package. If the height of solder bump is lower, the fatigue fracture of solder bump is faster. If the duration time of high and low temperatures is longer, the fatigue fracture due to creep of solder bump becomes faster. When the height of solder bump is change, the change of fatigue damage with plastic strain of solder bump will more obvious than the change of fatigue damage due to creep of solder bump. The extension of duration time of high and low temperatures will increase fatigue damage due to creep of solder bump, but not change the fatigue damage with plastic strain of solder bump. When the height of solder bump is reduced or the duration time of high and low temperatures is extended will increase fatigue damage subjected to cyclic temperature.

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The purpose of thesis is aimed to analyze fracture and fatigue behaviors of notched composite laminates by numerical method. Types of notch are both central notch 4mm£rand double-edged crack. We employed finite element method analysis with ANSYS to perform the numerical analysis. We adopted Tsai-Wu failure criterion to approach failure of central notch laminates by a step increment method and considered the effect of failure area gradually expanded, thus we obtained the ultimate stress of a laminate. In the work of fatigue testing and evaluation, we used Miner¡¦s rule to predict the extension of fatigue damage zone, and compared it with experimental results. In the analysis of a double-edged crack laminate, it is first assumed mix mode failure. Then, we calculated the stress intensity factors of various crack length by extrapolation, and developed a function of configuration correction factor. Finally, this study can be concluded as follows. The accuracy of ultimate stress prediction with step-by-step increment analysis is satisfactorily well. The outcome failure area of a laminate is closely corresponding with the observation of experiment. In predicting the fatigue damage zone, the predicted initial damage zone is close to experimental observation, but it is inconsistent with the actual damage extension due to crack propagation. Stress intensity factors and configuration correction factors are directly in proportion to the square root of crack length. It is corresponding with fracture mechanics. However there are some errors in quasi-isotropic laminates due to the existing of ¡Ó45¢Xplies.