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Breslavsky, D. V., O. K. Morachkovsky, and N. V. Shyriaieva. "Nonlinear vibrations and long-term strength of turbine blades." Thesis, National Technical University "Kharkov Polytechnic Institute", 2010. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41290.
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The method of a durability estimation of rotating turbomachinery blades at forced flexural-flexural-torsional vibrations is offered. The method is based on the methods of Continuous Damage Mechanics and the accurate strain analysis of the pre-twisted blades at the nonlinear vibrations with moderate displacements. The method to solve the strain analysis problem and turbomachinery blades high-cycle fatigue damage estimation as a result of nonlinear vibrations is presented.
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Hodgson, D. A. "The short and long term electric strength of polyethylene insulation." Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384272.
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Lin, Qiaoxing. "Strength degradation and damage micromechanism of granite under long-term loading." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37115406.
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Lin, Qiaoxing, and 林僑興. "Strength degradation and damage micromechanism of granite under long-term loading." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37115406.
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Perret, Olivier. "Strength and Stability of Cross-Laminated-Timber Walls at Short and Long Term." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1246/document.
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Ce mémoire de thèse aborde le problème du flambement de murs en bois lamellé-croisé. Ces panneaux de bois, constitués de planches collées perpendiculairement, sont de plus en plus utilisés dans la construction. La tendance actuelle du marché est de concevoir des immeubles de grande hauteur, ce qui soulève la question de la résistance en compression de ces murs. Il s'avère que le bois est fortement anisotrope. En particulier, la raideur et la résistance en cisaillement perpendiculaire aux fibres, également appelé cisaillement roulant, sont beaucoup plus faibles que dans la direction parallèle aux fibres. Ce fort contraste nécessite un critère de conception plus élaboré que les outils classiques utilisés dans l'ingénierie du bois. Ce travail est organisé en deux parties. Dans la première partie, la raideur équivalente de cisaillement transverse d'un panneau de bois lamellé-croisé est étudiée. Des bornes sont établies par une approche théorique. Ces bornes sont validées par un nouveau dispositif expérimental qui permet la mesure de la raideur en cisaillement roulant avec une variabilité plus faible que le test textit{single-lap} classiquement utilisé. Dans la deuxième partie, ces données sont utilisées dans l'analyse du flambement de panneaux en bois lamellé-croisé en raffinant progressivement le problème. Dans un premier temps, la charge critique de flambement linéaire d'une plaque épaisse sans imperfections est établie. Cette charge critique est basée sur une nouvelle théorie de plaque d'ordre supérieur et montre que la charge critique de flambement basée sur une théorie de plaque mince (Kirchhoff-Love) ne peut pas estimer correctement la résistance de murs en bois lamellé-croisé. Dans un second temps, l'influence des imperfections est étudiée en adaptant l'approche classique de Ayrton et Perry à une poutre de Timoshenko. Cette extension a révélé qu'un nouveau critère de résistance doit être satisfait lors du flambement qui est spécifique aux murs en bois lamellé-croisé. Dans un dernier temps, cette analyse est étendue aux charges permanentes en supposant une loi de fluage simple qui conduit à un nouveau critère de conception simple qui pourrait facilement être adopté dans les codes de conception actuels<br>This PhD thesis addresses the issue of CLT wall buckling. These wooden panels, made of boards which are glued cross-wise, are more and more used in construction. The current trend of the market is to design high-rise buildings which raises the issue of the compressive strength of such walls. It turns out that wood is a highly anisotropic material. Especially, the shear stiffness and strength perpendicular to the grain (rolling shear) are much weaker than in the direction parallel to the grain. This high contrast requires more elaborate design criteria than classical tools used in timber engineering. This work is organized in two main parts. First, the equivalent rolling-shear behavior of a CLT layer is investigated. Bounds are established for the stiffness of an equivalent layer using a theoretical approach. These bounds are validated by means of a new experimental set-up which allows the measurement of the rolling shear stiffness with less variability than the classical single lap shear test. In the second part, this data is used in the buckling analysis of CLT walls with increasing refinements. First, the linear buckling load of a thick plate without imperfection is established. This load is based on a new higher-order plate theory and reveals that the critical load based on a thin plate theory (Kirchhoff-Love) cannot predict correctly the strength of CLT walls. Then, the influence of imperfections is introduced adapting the classical approach from Ayrton and Perry to the case of a Timoshenko beam. This extension reveals that a new design criterion has to be satisfied under buckling which is specific to CLT. Finally, this analysis is extended to long term loads assuming a simple creep law and leading to a new simple design criterion which may be easily introduced in current design codes
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Aslan, Ozlem. "Predicting Long Term Strength Of Roller Compacted Concrete Containing Natural Pozzolan By Steam Curing." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607727/index.pdf.
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Roller Compacted Concrete (RCC) is new technology gaining popularity in the recent years due to its low cost, rapid construction, and using opportunity of by-products. RCC is widely used in the world. However, the use of RCC has been restricted to construction of few cofferdams, and limited to local use in dam construction up to date.
In this thesis, two types of cement, two types of natural pozzolan, aggregates with varying gradations, and a type of water reducing chemical admixture were used. Prior to carrying out the tests, the chemical and physical properties of materials were determined. Additionally, steam curing was applied to the test specimens in order to get long term compressive strength at early ages. Differences between steam cured specimens and normal cured specimens have been discussed in the discussion part.
In the study, the results indicate that usage of water reducing chemical admixture improves compressive strength of RCC. Moreover, it is revealed that usage of fine material is essential to obtain desired results since the amount of cementitious materials is considerably low in RCC. Steam curing is known as its property of providing long term compressive strength at early ages. It was observed that application of steam curing in CEM I type cement used RCC mixtures generated expected results. However, in CEM IV type cement used RCC mixtures compressive strength results did not behave in the same manner.
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Kotrappa, Neel. "The Efficacy of Long-Term Kinesio Tape on Grip Strength in a Healthy Population." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/cmc_theses/976.
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Kinesio® Tape was invented in 1973, and since has been used in various clinical and therapy settings to prevent and heal a multitude of physical conditions. Kinesio® Tape is a 100% cotton-based elastic tape that when applied to the skin pulls the skin upwards and creates more space by lifting the fascia and soft tissue, thus increasing blood flow and decreasing edema. The tape was also purported to facilitate the strengthening of weakened muscles through neuromuscular facilitation. The objective behind this study was to determine the long-term effects of applied forearm Kinesio® Tape on maximal grip strength when paired with an exercise program. The study took place at the CMS Athletic Training Center, and was designed to be a matched-pairs, single group, repeated measures experiment. Thirty- two healthy members of the Claremont College community voluntarily participated in this study. There was 16 male and 16 female participants (average age: 21.46 ± 1.76 years; average height 174.92 ± 9.40 cm; average body weight 69.17 ± 9.20 kg). The maximal grip strength of both the dominant and non-dominant hands was measured using a JAMAR Hydraulic Hand Dynamometer. Each of the 32 subjects also participated in an exercise program for two weeks and provided a grip strength measurement at the end of each week. Maximal grip strength values were assessed using a standard paired-samples t-test. Results revealed a significant difference in grip strength in the dominant arm (exercise with Kinesio® Tape) compared to the non-dominant arm (exercise only). When combined with a relatively low to medium level exercise program, Kinesio® Tape significantly increased grip strength when compared to an exercise program alone in a healthy population.
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Pentland, Wendy E. "Upper extremity function in long term paraplegia and implications for independence." Thesis, Curtin University, 1992. http://hdl.handle.net/20.500.11937/2435.
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The intent of this study was to describe the effects of long term paraplegia and wheelchair use on upper limb function. Bilateral upper extremity isokinetic and grip strength, pain, and active range of motion were compared in 52 men with paraplegia (mean age 44 years: mean duration of spinal cord injury (SCI) 17 years) and 52 age and activity-level matched able-bodied men. The impact of upper limb pain on activities of daily living (ADL) performance was examined in the paraplegic sample. Strength was not significantly different between the two samples except for bilateral shoulder flexion (able-bodied stronger) and bilateral elbow extension (paraplegia stronger). Strength changed similarly with age in the two groups. The effect of duration of SCI on strength, excluding age, was significant for grip strength only. Duration of paraplegia and activity-level were better predictors of strength than age in 9 of 14 muscle groups, whereas in the able-bodied, age was the best strength predictor. Limited bilateral shoulder internal rotation and non-dominant external rotation were associated with paraplegia. Upper limb pain in the past week was associated with paraplegia (shoulder p<.001; elbow p<.00l; wrist/hand p<.00l). Reported pain prevalences for the paraplegic sample were: shoulder 39%, elbow 31%, wrist/hand 40%. The paraplegic subjects' pain intensity ratings revealed them to be experiencing mild to moderate levels of upper limb pain. Shoulder pain was associated with duration of injury, exclusive of age (p<.05). Measurement of the impact of upper limb pain On 18 activities of daily living (ADL) tasks revealed pain to be experienced by the majority of subjects with paraplegia (mobility tasks 60%; self-care tasks 5 8 % ; general activities tasks 60%). However, only 23-35% had made changes in their routines, and 6-16% had sought assistance with ADL due to upper limb pain. When age was excluded, it appeared that duration of SCI was more associated with pain during ADL, but this was significant only for pain during self-care tasks. The tasks most reported to cause upper limb pain were work/school, sleep, wheelchair transfers, outdoor wheeling, and driving. These results suggest that preventative and management steps are required to ensure continued independence and quality of life in this group over time. The effect of duration of SCI suggests that limitations in upper limb function may be seen in this population at relatively young ages.
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Layne, Andrew S., W. Guy Hornsby, D. E. Corriher, et al. "Long Term Athlete Monitoring: Changes in Isometric Strength and Explosiveness in Division I NCAA Athletes." Digital Commons @ East Tennessee State University, 2009. https://dc.etsu.edu/etsu-works/4109.
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Pentland, Wendy E. "Upper extremity function in long term paraplegia and implications for independence." Curtin University of Technology, School of Physiotherapy, 1992. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=15684.
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The intent of this study was to describe the effects of long term paraplegia and wheelchair use on upper limb function. Bilateral upper extremity isokinetic and grip strength, pain, and active range of motion were compared in 52 men with paraplegia (mean age 44 years: mean duration of spinal cord injury (SCI) 17 years) and 52 age and activity-level matched able-bodied men. The impact of upper limb pain on activities of daily living (ADL) performance was examined in the paraplegic sample. Strength was not significantly different between the two samples except for bilateral shoulder flexion (able-bodied stronger) and bilateral elbow extension (paraplegia stronger). Strength changed similarly with age in the two groups. The effect of duration of SCI on strength, excluding age, was significant for grip strength only. Duration of paraplegia and activity-level were better predictors of strength than age in 9 of 14 muscle groups, whereas in the able-bodied, age was the best strength predictor. Limited bilateral shoulder internal rotation and non-dominant external rotation were associated with paraplegia. Upper limb pain in the past week was associated with paraplegia (shoulder p<.001; elbow p<.00l; wrist/hand p<.00l). Reported pain prevalences for the paraplegic sample were: shoulder 39%, elbow 31%, wrist/hand 40%. The paraplegic subjects' pain intensity ratings revealed them to be experiencing mild to moderate levels of upper limb pain. Shoulder pain was associated with duration of injury, exclusive of age (p<.05). Measurement of the impact of upper limb pain On 18 activities of daily living (ADL) tasks revealed pain to be experienced by the majority of subjects with paraplegia (mobility tasks 60%; self-care tasks 5 8 % ; general activities tasks 60%). However, only 23-35% had made changes in their routines, and 6-16% had sought assistance with ADL due to upper limb pain. ++<br>When age was excluded, it appeared that duration of SCI was more associated with pain during ADL, but this was significant only for pain during self-care tasks. The tasks most reported to cause upper limb pain were work/school, sleep, wheelchair transfers, outdoor wheeling, and driving. These results suggest that preventative and management steps are required to ensure continued independence and quality of life in this group over time. The effect of duration of SCI suggests that limitations in upper limb function may be seen in this population at relatively young ages.
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Qamar, Muhammad Mustafa. "Long-term strength training reverses the effects of aging on skeletal muscle of health elderly men." Thesis, Örebro universitet, Institutionen för hälsovetenskap och medicin, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-27486.
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Introduction: Aging is related to a gradual decline in skeletal muscle mass, which is associated with morphological modifications such as reduced muscle fiber cross-sectional area and satellite cell content. Data also suggest that a short-term strength training period can be an effective instrument to rejuvenate these morphological parameters and to restore muscle mass. Therefore, the aim of this study is to investigate the effects of one year progressive strength training on fiber type-specific morphological parameters (fiber type composition, fiber area, satellite cell content, myonuclear number and domain) in skeletal muscle of elderly men. Methods: Thirteen healthy elderly men (age range, 66-77 years) were randomly assigned into training (T) (n=7) and control (C) (n=6) groups. 52 weeks of progressive strength training was performed. Before and after the training, muscles biopsies were collected from the middle part of the vastus lateralis by percutaneous needle biopsy technique. Muscle biopsies were examined for muscle fiber type composition, fiber type-specific hypertrophy and alterations in satellite cell content, myonuclear content and domain using immuno-histochemistry. Results: At baseline, myonuclear content and mean fiber area was larger in type I fibers compared to type II fibers (p<0.05). No statistically significant differences were found in fiber type composition, mean fiber area, satellite cell content and myonuclear domain between T and C groups at baseline. By the end of the training period, fiber area was increased by 59% (p<0.05) in type I and 71% (p<0.05) in type II. Satellite cell content, myonuclear content and myonuclear domain were increased after training in type I by 58% (p<0.05), 33% (p<0.05), and 20% (p<0.05), respectively. Similar increases in satellite cell content (+65%; p <0.05), myonuclear content (+36%; p <0.05) and myonuclear domain (+25%; p<0.05) were seen in type II fibers. Conclusion: The current study reported that long-term strength training is an excellent tool to prevent sarcopenia. It is demonstrated that skeletal muscle in elderly is capable to enhance satellite cell and myonuclear content, which contributed to muscle hypertrophy.<br><p>presentation was made in august 2012 and thesis is approved and got result as well in november 2012</p><p>For an enhanced reading experience go to a later version: http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-31017.</p><br>This study was a part of a larger research project studying adaptations to strength, endurance and combined training
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Waldron, Christopher Joseph. "Investigation of Long-Term Prestress Losses in Pretensioned High Performance Concrete Girders." Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/29672.
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Effective determination of long-term prestress losses is important in the design of prestressed concrete bridges. Over-predicting prestress losses results in an overly conservative design for service load stresses, and under-predicting prestress losses, can result in cracking at service loads. Creep and shrinkage produce the most significant time-dependent effect on prestress losses, and research has shown that high performance and high strength concretes (HPC and HSC) exhibit less creep and shrinkage than conventional concrete. For this reason, the majority of traditional creep and shrinkage models and methods for estimating prestress losses, over-predict the prestress losses of HPC and HSC girders.
Nine HPC girders, with design compressive strengths ranging from 8,000 psi to 10,000 psi, and three 8,000 psi lightweight HPC (HPLWC) girders were instrumented to determine the changes in strain and prestress losses. Several creep and shrinkage models were used to model the instrumented girders. For the HPLWC, each model over-predicted the long-term strains, and the Shams and Kahn model was the best predictor of the measured strains. For the normal weight HPC, the models under-estimated the measured strains at early ages and over-estimated the measured strains at later ages, and the B3 model was the best-predictor of the measured strains. The PCI-BDM model was the most consistent model across all of the instrumented girders.
Several methods for estimating prestress losses were also investigated. The methods correlated to high strength concrete, the PCI-BDM and NCHRP 496 methods, predicted the total losses more accurately than the methods provided in the AASHTO Specifications. The newer methods over-predicted the total losses of the HPLWC girders by no more than 8 ksi, and although they under-predicted the total losses of the normal weight HPC girders, they did so by less than 5 ksi.<br>Ph. D.
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Gervais, Olivier. "Effects of Long-Term Selection for Non-Destructive Deformation in White Leghorns." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/217200.
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Quinlan, Shayan Lian. "The long-term effects of shoe flexibility on a child’s foot development and gross motor skill performance." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/27614.
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A barefoot childhood results in improved foot morphology, as well as superior gross motor skills, compared to a shod childhood. Acute effects of conventional shoes are detrimental to children’s foot and ankle biomechanics. There is no consensus amongst foot health professionals on how the midfoot part of the shoe should be made for children. To date, no research into the long-term effects of shoe design on children’s foot health has been conducted. This thesis aimed to establish: a link, if any in the literature between toe flexor strength and balance in children, a flexible shoe comparative to a standard school shoe via laboratory 3D motion capture testing, a new reliable toe flexor strength testing protocol for children, the long-term effects of wearing flexible versus stiff school shoes on foot and gross motor skill development in children aged 9-12-years (randomised controlled trial – RCT), and finally, children’s shoe design preferences. These aims were achieved by establishing that toe flexor strength is correlated to balance in older adults (> 60 years) in the literature, and this same correlation exists in children (RCT results). Flexible shoes resulted in substantially more mid-foot power output with plantarflexion compared to standard school shoes in the laboratory. The novel dynamometer setup and protocol was highly reliable for test-retesting of children’s toe flexor strength. The longitudinal RCT provided the first evidence that flexible shoes over time substantially improve children’s semi-dynamic balance and moderately improve foot muscle size and strength. Children prefer flexible and cushioned shoes for comfort. The overarching aim of this thesis was to benefit children; and children’s shoe manufacturers, foot health professionals and parents should consider increased shoe flexibility as a beneficial and preferred aspect of shoe design for children’s comfort, improved foot strength and gross motor skill development.
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Puhke, Raivo. "Adaptive changes of myosin isoforms in response to long-term strength training in skeletal muscle of middle-aged persons /." Online version, 2006. http://dspace.utlib.ee/dspace/bitstream/10062/1129/5/puhkeraivo.pdf.
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Lee, Won-Jun. "Relationship between lower body strength and bone mineral density in postmenopausal women with long-term exercise training." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1177979.
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The purpose of this study was (1) to compare the lower body strength, power, and the bone mineral density (BMD) of the proximal femur in a group of trained postmenopausal women who have been in low intensity exercise program for a long time with age-matched sedentary controls, and (2) to evaluate the magnitude of the correlation between muscle function and site-specific BMD in these postmenopausal women. Healthy postmenopausal women (n = 17) between the age of 60 and 80 were divided into two groups: 9 exercisers (mean ± SE, 74.8 ± 3.2 years) who had been in an exercise training program for at least 5 years and 8 control (mean ± SE, 71.6 ± 3.4 years) who had not been in any exercise program for at least 5 years. The exercise group performed three one hour sessions a week of aerobic and resistance training for an average of 9.9 years. The exercise training consisted of 30 minutes walking and one or two sets of twelve to fifteen repetitions focused on large muscle groups. The BMD of the proximal femoral region was assessed using dual-energy x-ray absorptiometry (DEXA). By using a Cybex Leg Press machine, 1-repetition maximum (1-RM) tests were performed for lower body strength and power of lower body were obtained by a seated chair rise. Statistical analysis demonstrated no statistical differences between the left and right region of the femur BMD for either group, with the averaged BMD being 0.858 g/cm2 for the controls and 0.853 g/cm2 for the exercisers. The trochanter BMD for the exercisers were 7 % (left) and 6 % (right) higher than the controls although these values were not statistically significant. The 1RM leg press strength ranged from 29.5 to 47.6 kg (mean ± SE, 40.21 ± 2.62 kg) in controls and from 31.8 to 61.2 kg (mean ± SE, 45.93 ± 3.72 kg) in exercisers. Although the exerciser group lifted 14.2 % more weight than the control group, the difference was not statistically significant. The results of power test ranged from 14.59 to 31.21 kg • m/sec (mean ± SE, 22.94 ± 5.67 kg • m/sec) in controls and from 13.63 to 38.60 (mean ± SE, 28.88 ± 6.81 kg • m/sec). The power did not differ significantly between the two groups. However, it is noted that between group differences approached significance at p < 0.07. Correlations between body composition and femoral neck BMD were also determined. Neither weight, nor BMI was significantly correlated with femoral neck BMD in the exercise and control group. Lower body strength and power did not correlate with the BMD of the femoral neck, Ward's triangle, or trochanter in either group. Although the BMD of the proximal femoral region did not differ between two groups the higher mean age (+ 3.2 years) of the exercise group suggested that a low intensity exercise training program can increase power and strength and maintain BMD in postmenopausal women. However, the low intensity of resistance training program utilized by the exercise group was no more effective in maintaining BMD than an active lifestyle.<br>School of Physical Education
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Oldham, R. H. "The influence of water on long-term strength properties of coal measures rocks associated with mining excavations." Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355420.
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Damiani, Thomas Miles. "A model to predict the long-term strength of e-glass fiber composites subjected to environmental exposure." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1517.
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Thesis (M.S.)--West Virginia University, 2000.<br>Title from document title page. Document formatted into pages; contains xiii, 86 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 81-84).
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Mitsui, Yuta. "Study on relationships between frictional strength and long-term fault behavior including evolution of pore fluid pressure." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/135410.
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Dook, Jan. "The effect of long term training on the bone mineral density and muscle strength of perimenopausal athletes." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1994. https://ro.ecu.edu.au/theses/1093.
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The aim of this research was to determine if long term training (20 years+) in a high impact weight bearing sport (netball/basketball: NB/88), a low impact weight-bearing sport (running/ field hockey: GEN) and a non weight-bearing sport, swimming (SWI) produced a positive relationship with regional bone mineral density (BMD) and muscle strength. Method: Three groups of perimenopausal athletes (n=20) plus a control group (CON) (n=20) had Total Body BMD and body composition measured by DEXA (Hologic QDR 2000) and isometric strength of dominant arm flexors and leg extensors by a strain tensiometer connected to a strength chair. Differences between groups were determined by ANOVA followed by Scheffe Test and correlations by Pearson r. General characteristics, including age, height, weight and calcium intake showed no statistical differences.
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Esposito, Alessandro. "Creep deflection of low-strength reinforced concrete flexural members strengthened with carbon fiber composite sheets." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10340/.
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The low-strength concrete is defined as a concrete where the compressive cubic strength is less than 15 MPa. Since the beginning of the last century, many low-strength concrete buildings and bridges have been built all over the world. Being short of deeper study, composite sheets are prohibited in strengthening of low-strength reinforced concrete members (CECS 146; ACI 440). Moreover, there are few relevant information about the long-term behavior and durability of strengthened RC members.
This fact undoubtedly limits the use of the composite materials in the strengthening applications, therefore, it is necessary to study the behaviours of low-strength concrete elements strengthened with composite materials (FRP) for the preservation of historic constructions and innovation in the strengthening technology.
Deformability is one of criteria in the design of concrete structures, and this for functionality, durability and aesthetics reasons. Civil engineer possibly encounters more deflection problems in the structural design than any other type of problem. Many materials common in structural engineering such as wood, concrete and composite materials, suffer creep; if the creep phenomenon is taken into account, checks for serviceability limit state criteria can become onerous, because the creep deformation in these materials is in the same order of magnitude as the elastic deformation.
The thesis presents the results of an experimental study on the long-term behavior of low-strength reinforced concrete beams strengthened with carbon fiber composite sheets (CFRP). The work has investigated the accuracy of the long-term deflection predictions made by some analytical procedures existing in literature, as well as by the most widely used design codes (Eurocode 2, ACI-318, ACI-435).
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Kavanaugh, Ashley A. "Longitudinal Changes in Strength and Explosive Performance Characteristics in NCAA Division I Women’s Volleyball Athletes." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2315.
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The purpose of this dissertation was to determine if a periodized strength and conditioning program resulted in long-term adaptations in NCAA Division I women’s volleyball athletes, and if these changes related to the team’s competitive performance. Specifically, this dissertation serves to: 1.) describe the changes in body composition and performance variables of 2 female volleyball athletes over a 4-year collegiate career, 2.) determine the degree and magnitude of change in performance variables after about 1, 2, and 3 years of periodized resistance training, and 3.) infer if volleyball performance characteristics are related to a team’s competitive success. The following are major findings of this dissertation. 1.) Positive changes in vertical jump height, strength, and explosiveness may be possible throughout 4 years of collegiate volleyball training even with increased body mass and percent body fat. Moreover, impaired ability to perform heavy lower-body resistance training exercises due to chronic injury negatively impacts long-term physical performance adaptations over 4 years. 2.) A combination of traditional resistance training exercises and weightlifting variations at various loads, in addition to volleyball practice, appear to be effective at increasing maximal strength by 44% and vertical jump height by 20%-30% in NCAA Division I women’s volleyball athletes after about two and half years of training. Furthermore, these characteristics can be improved in the absence of additional plyometric training outside of normal volleyball-specific practice. 3.) A rating percentage index RPI ranking ratio and unweighted match score ratio appear to be better predictors of overall team competitive season success than a weighted match score ratio. On the contrary, a weighted match score ratio may be better for determining an association between team match performance and volleyball-specific fitness. A considerable amount of research is needed to develop a volleyball-specific performance index that best quantifies team performance and whether or not a measurable association exists between improved fitness characteristics and increased overall team competitive success. The findings of this dissertation provide evidence that analyzing and monitoring volleyball-related performance variables over time can assist the sport performance group in making training based decisions as well as promote the successful development of an athlete.
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Daftary, Ameet Shirish. "Effect of Long Term Steroids on Cough Efficiency and Respiratory Muscle Strength in Patients with Duchenne Muscular Dystrophy." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1170363103.
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Butler, Tiffiny A. "THE EFFECTS OF POST PUBERTAL FOOD RESTRICTION ON BONE ARCHITECTURE, STRENGTH, AND MEDULLARY ADIPOSE COMPOSITION." Diss., Temple University Libraries, 2013. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/244901.
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Kinesiology<br>Ph.D.<br>The purpose of this investigation was to determine the effects of post pubertal caloric restriction on bone architecture, strength, and medullary adipose quantity. A randomized control comparison design was utilized and the study was conducted in a laboratory setting. All procedures were approved by the Institutional Animal Care and Use Committee (IACUC) at Temple University (protocol number 3396). Female Sprague Dawley rats (23days-of-age, n=120) were randomly assigned into seven groups, baseline (BL) (n=18), control (C) (n=17), caloric restriction (FR) (n=17), control recovery (RC) (n=17), caloric restriction recovery (RFR) (n=17), control ovariectomy (COVX) (n=17) and food restricted ovariectomy (FROVX) (n=17). On day 65, a 6 week 30% caloric restriction protocol was administered. Following food restriction, a subset of the control and food restricted groups were sacrificed (n=34) and the remaining animals (n=68) control recovery (RC) and food restricted recovery (RFR) groups had a 10 week recovery with ad lib food. Recovery groups, RC and RFR: were sacrificed after the 10 week recovery period at 183 days of age (n=34). The remaining animals were ovariectomized (OVX) and grouped into control ovariectomy (COVX) and food restricted ovariectomy (FROVX). Six weeks post OVX the animals were sacrificed at 270 days of age. After sacrifice blood was taken by cardiac puncture, bones were harvested, cleaned of soft tissue, fixed and prepared for analysis. Anthropometric measurements were taken including retroperitineal and gonadal fat pad weights as well as adrenal glands, ovaries, uteri, and tricep surae muscle group weights. Main Outcome Measures: The outcome variables for this study were bone mechanical competence, trabecular and cortical bone mass and architecture, marrow adipocyte number as well as serum markers of bone formation and resorption. Insulin - like growth factor - 1 (IGF-1) and C- terminal telopeptide (CTX) was measured to determine bone formation and resorption. Statistical Analysis: One-way Analysis of Variance (ANOVA) was performed to determine differences between all groups. Tukey's honestly significant difference (HSD) post hoc analysis was conducted to determine differences between groups. Student's t - tests were used to detect differences between age groups (acute, recovery, post-OVX) A p value was set at less than or equal to 0.05 for all statistical tests. All statistical analysis was performed using (GraphPad Prism version 5.00 for Windows, GraphPad Software, San Diego California USA). Variables were normalized with a linear regression-based correction using body weight. All variables with an R2 level greater than 0 were normalized to avoid choosing an arbitrary R2 value as a cut-off for normalization. Results: Body weight was 18% lower than control animals following caloric restriction. Weight loss was due to fat mass predominately; muscle mass was maintained relative to body weight. Bone length and growth rates were diminished however no differences were found following refeeding. No differences were found in bone strength at any time point. However relative to body weight peak moment and stiffness were significantly higher following caloric restriction. Cortical bones mass and cross sectional moment of inertia were enhanced in the femoral diaphysis with bone mass greater post OVX in the calorically restricted group (FR-OVX). No significant differences were found in ash percent in the femur was found between any groups at any time point however vertebral bone mineral density in acute FR and post OVX time points in FROVX was significantly greater indicating an enhanced bone quality in the restricted. No change in trabecular quantity or quality were observed in the distal femur between groups however vertebral trabecular architecture was enhanced in number and thickness in acute FR and post OVX time points in FROVX. No significant difference in number of marrow adipocytes were found at any time point. Serum CTX decreased significantly in acute in FR and increased at recovery in RFR and post OVX in FROVX. Serum IGF - 1 decreased in the acute FR with IGF - 1 significantly greater after recovery in RFR. Conclusions: Evidence was found to suggest that moderate caloric restriction (nutrient replete) post puberty was positive for bone. Bone quantity was increased with relative cortical area and bone area relative to body weight increased in the FR group. Significant increases in FROVX bone quantity post OVX suggests that bone mass gains during caloric restriction attenuated cortical bone loss at maturity post OVX. Bone quality increases in cross sectional moment of inertia relative to body weight may have accounted for the transient increase in FR bone strength in the femur. Decreases in acute CTX and IGF- 1 levels indicates that bone formation and resorption were decreased during development that may have been the mechanism for bone loss attenuated post OVX in calorically restricted. Growth rate slowing during caloric restriction may have decreased the rate of formation and resorption during a crucial time of peak bone mass accrual and bone modeling. This decrease in one modeling may have been mechanism that preserved bone quantity during acute caloric restriction. Increases in femur quality in polar moment of inertia coupled with a decrease in bone length changed the shape of the bone making it more robust. A shorter bone with a thicker cortex with no change in mineral content may have been the mechanism in the transient increase in bone strength in the femur. Quality changes in mineral density in vertebrae acting as a mineral storage back up as a last resort if quantity and quality changes were not sufficient in maintain bone strength. Moderate caloric restriction transiently increased strength, by increasing bone mass relative to body, altering bone geometry and increased vertebral mineral density.<br>Temple University--Theses
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Altunsoz, Omur Serdal. "Determine The Effects Of Long Term Playing Soccer On The Degeneration Of Lumbar Spine." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607487/index.pdf.
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The main purpose of this study was to determine whether playing soccer at high
intensity training for a long period causes degeneration of the lumbar spine or not.
This degeneration may occur without any symptoms or low back pain. Results of the
present study were discussed in the framework of lumbar disc degeneration, trunk
strength, lumbar and hip bone mineral density, trunk flexibility, activity MET scores
for active and veteran soccer groups. There have been four subject groups in this
study (15 active soccer players, 15 sedentary participants, 14 veteran soccer players,
13 sedentary participants). The BMD was measured in anterior-posterior view with a
second-generation dual energy X-ray absorptiometry (DEXA) device. Isokinetic
trunk strength data were recorded with the Biodex System Dynamometer (Biobex
Medical Inc, Shirly, NY) at the 60º<br>/sec and 120º<br>/sec. Plain lateral radiographs were
taken. The presence of degenerative changes of each lumbar vertebra was determined
by using the Kellgren and Lowrence Score. A modified Schober test was used to
measure lumbar flexion. Findings of the study demonstrated that veteran soccer
players displayed greater lumbar disc degeneration than other groups. Moreover,
v
active soccer group had more BMD than other groups, but the veteran group&<br>#8217<br>s BMD
results were not different while comparing the control participants. Isokinetic test
findings of the current study, trunk extension strength at 60/sec was significantly
higher in active 1st group players than 2nd group participants, but there were no
significant differences between the 1st group and 2nd group in terms of trunk flexion
strength and agonist/antagonist ratio at 60/sec. In conclusion, Findings of the study
support the main hypothesis that playing soccer at high intensity training at a long
period of time may cause lumbar spine degeneration. Degeneration may occur
without low back symptoms. Moreover, results supported the idea that Soccer can be
accepted an impact loading sport that are to keep or accelerate bone mineral density.
At last, having abnormal trunk extension strength while playing actively may cause
lumbar disc degeneration on the spine at later years. A similar study should be
carried out with a larger number of subjects, and longitudinal studies should be
designed to examine the factors that effect the degeneration on the lumbar spine.
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Li, Y. "Resource allocation for coordinated multipoint joint transmission system and received signal strength based positioning in long term evolution network." Thesis, University of Liverpool, 2017. http://livrepository.liverpool.ac.uk/3009494/.
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The Long-Term Evolution Advanced (LTE-A) system are expected to provide high speed and high quality services, which are supported by emerging technologies such as Coordinated Multipoint (CoMP) transmission and reception. Dynamic resource allocation plays a vital role in LTE-A design and planning, which is investigated in this thesis. In addition, Received Signal Strength (RSS) based positioning is also investigated in orthogonal frequency division multiplexing (OFDM) based wireless networks, which is based on an industry project. In the first contribution, a physical resource blocks (PRB) allocation scheme with fuzzy logic based user selection is proposed. This work considers three parameters and exploit a fuzzy logic (FL) based criterion to categorize users. As a result, it enhances accuracy of user classification. This work improves system capacity by a ranking based PRBs allocation schemes. Simulation results show that proposed fuzzy logic based user selection scheme improves performance for CoMP users. Proposed ranking based greedy allocation algorithm cut complexity in half but maintain same performance. In the second contribution, a two-layer proportional-fair (PF) user scheduling scheme is proposed. This work focused on fairness between CoMP and Non-CoMP users instead of balancing fairness in each user categories. Proposed scheme jointly optimizes fairness and system capacity over both CoMP and Non-CoMP users. Simulation results show that proposed algorithm significantly improves fairness between CoMP and Non-CoMP users. In the last contribution, RSS measurement method in LTE system is analyzed and a realizable RSS measurement method is proposed to fight against multipath effect. Simulation results shows that proposed method significantly reduced measurement error caused by multipath. In RSS based positioning area, this is the first work that consider exploiting LTE’s own signal strength measurement mechanism to enhance accuracy of positioning. Furthermore, the proposed method can be deployed in modern LTE system with limited cost.
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Harrison, Alex. "The Bobsled Push Start: Influence on Race Outcome and Push Athlete Talent Identification and Monitoring." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etd/3313.
Full textAbstract:
Bobsled is an Olympic sport that has progressed from rudimentary in the 1800’s to highly technological replete with biomechanical analyses and investment in engineering from the world’s top engineers. Little to no investigation has been carried out on all the tracks and the interrelationship between various measures of starts and sled-travel down-track. Further, little quality research has been produced in the athletic characteristics required for high-level competition in bobsled.
The present manuscript investigates the reliability of, and interrelationship between, start time, start velocity, split times, and finish times in World Cup 2- and 4-man bobsled competition. A strong relationship between the three variables is found, but further research is needed to elucidate the actual effects of the push start on the sled’s travel down-track because of several confounding variables.
The present manuscript also investigates the tests commonly performed by the USA Bobsled and Skeleton federation as a means of talent identification and athlete monitoring. Strength and power tests may have more validity for discriminating between higher-level push athletes, so long as a sufficient threshold of running speed is present. Speed tests only discriminate well between lower level push athletes. Recommendations are made for modifying the current testing battery in such a way as to better identify talent and better monitor traveling athletes and informing coaching decisions about athlete preparedness for fast bobsled push starts.
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Shaheen, Ehab T. "Long Term Performance of Corrugated HDPE Pipes Produced with Post-Consumer Recycled Materials Under Constant Deflection." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1541422245636659.
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Mahal, Raj-Deep Singh. "A standardized approach to determine the effect of thermocycling and long term storage on the shear bond strength of orthodontic brackets cemented to bovine enamel." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0021/MQ53415.pdf.
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Aboualmal, Abdulhadi M. A. "Analysis and modelling of the impact of anomalous propagation on terrestrial microwave links in a subtropical region, based on long-term measurements : statistical analysis of long-term meteorological and signal strength measurements in a subtropical region and investigation of the impact of anomalous refractivity profiles on radio propagation in terrestrial microwave wireless systems." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/14804.
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Prevailing propagation phenomena in certain areas play a vital role in deciding terrestrial wireless systems performance. Vertical refractivity profile below 1 km is a critical parameter for designing reliable systems; noting that there is a shortage of upper-air data worldwide. Anomalous phenomena may cause severe signal fading and interference beyond the horizon. The objectives of this thesis are to investigate dominant refractive conditions in the subtropical Arabian Gulf region, develop new approaches and empirical models for evaluating vertical refractivity profiles and relevant propagation parameters in the low troposphere, and to examine the impact of frequently experienced anomalous phenomena on terrestrial microwave links. Twenty-three years of meteorological measurements, from 1990 to 2013, are utilized using spatially separated surface stations and a single radiosonde in the United Arab Emirates (UAE). Profiles of sea level, surface and upper refractivity components are statistically analysed. Three major atmospheric layers; namely 65 m, 100 m and 1 km above the ground are studied to analyse relevant propagation parameters such as sub-refraction, super-refraction, anomalous propagation probability parameter β0 and point refractivity gradient not exceeded for 1% of time. The effective earth radius factor k is investigated using a new weighted averaged approach. In addition, the seasonal structure of atmospheric ducting is dimensioned within 350 m layer above ground. Finally, microwave measurement campaign is conducted using multiple radio links operating in UAE using various frequency bands. The link budget simulations are compared with the signal strength measurements. Fading scenarios are studied against the observed anomalous conditions and several recommendations are concluded.
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Heikkinen, J. (Juuso). "Recovery of calf muscle isokinetic strength after acute Achilles tendon rupture." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526216195.
Full textAbstract:
Abstract Achilles tendon rupture (ATR) conservative treatment result usually good clinical outcome, but despite the treatment method calf muscle strength deficit persist. Recent evidence suggests that surgery might surpass conservative treatment in restoring strength after ATR, but structural explanations for surgery-related improved strength remain uncertain. The purposes of this thesis were to compare calf muscle isokinetic strength recovery, calf muscle volume, fatty degeneration and AT elongation after conservative treatment or after open surgical repair of ATR. An additional aim was to assess the role of fascial augmentation in terms of calf muscle isokinetic strength recovery, AT elongation, calf muscle volume atrophy and fatty degeneration, and their relationship with calf muscle isokinetic strength in long-term follow-up after ATR surgery. Surgery resulted in 10% to 18% greater plantar flexion strength (P = 0.037) compared to conservative treatment. The mean differences between affected and healthy soleus muscle volumes were -18% after surgery and -25% after conservative treatment (P = 0.042). At 18 months, AT were, on average 19 mm longer in patients treated conservatively compared to surgery (P < 0.001). At 18 months, patients with greater (2–3) fatty degeneration had lower soleus muscle volumes and plantar flexion strength in the healthy leg. In long term, augmentation did not affect any of the strength variables, but the injured side showed 12% to 18% strength deficit compared with the healthy side (P < 0.001). The AT was, on average, 12 mm longer in the affected leg than in the healthy leg (P < 0.001). The mean soleus muscle volume was 13% lower in the affected leg than in the healthy leg (P < 0.001). The mean volumes of the medial- and lateral gastrocnemius muscles were 12% and 11% lower in the affected leg than in the healthy leg, respectively (P < 0.001). AT elongation correlated substantially with plantar strength deficit (ρ = 0.51, P < 0.001) and with both gastrocnemius (ρ = 0.46, P = 0.001) and soleus muscle atrophy (ρ = 0.42, P = 0.002). Calf muscle fatty degeneration was more common in the affected leg compared healthy leg (P ≤ 0.018). In conclusion, surgery of ATR restored calf muscle isokinetic strength earlier and more completely than conservative treatment. Conservative treatment resulted in greater soleus muscle atrophy and AT elongation compared surgery, which may partly explain the surgery related better strength results. Augmentation provided no long-term benefits compared with simple suturation, and a 12 to 18% plantar flexion strength deficit compared to the healthy side persisted. AT elongation may explain the smaller calf muscle volumes, greater fatty degeneration, and plantar flexion strength deficit observed in long-term follow-up after surgical repair of ATR<br>Tiivistelmä Akillesjännerepeämän (ATR) konservatiivisella ja leikkaushoidolla hoidolla saavutetaan hyvät kliiniset tulokset. Viimeisimmät tutkimukset kuitenkin viittaavat leikkaushoidolla saavutettavan paremmat voimat kuin konservatiivisella hoidolla, mutta rakenteelliset selitykset leikkaushoidon paremmalle pohjelihaksen voimille ovat epäselviä. Työn tarkoituksena oli verrata pohjelihaksen isokineettisten voimien palautumista, pohjelihastilavuuksia, rasvadegeneraatiota ja akillesjänteen (AT) pidentymistä ATR:n konservatiivisen- ja leikkaushoidon jälkeen. Tarkoituksena oli arvioida lihaskalvovahvikkeen merkitystä pohjelihaksen isokineettisten voimien palautumisessa pitkäaikaisseurannassa. Lisäksi tutkimme AT pidentymisen, pohjelihastilavuuksien ja rasvadegeneraation suhdetta pohjelihaksen isokineettisiin voimiin ATR:n leikkaushoidon jälkeen 14 v seurannassa. Leikkaushoidolla saavutettiin 10–18 % paremmat pohjelihaksen voimat verrattuna konservatiiviseen hoitoon. Leikkaushoidon jälkeen soleuslihasten tilavuuksien puoliero terveen jalan hyväksi oli 18 % ja konservatiivisen hoidon jälkeen 25 %. 18 kk kohdalla konservatiivisesti hoidettujen AT oli 19 mm pidempi verrattuna leikkauksella hoidettuihin. 18 kk kohdalla potilaat, joilla vamma jalan soleuslihaksen rasva-degeneraatio oli korkea (2–3), kärsivät suuremmasta soleuslihaksen atrofiasta ja pohjelihaksen voima puolierosta. Voimat eivät muuttuneet 12 kk ja 14 v kontrollien välillä. Lihaskalvovahvikkeella ei ollut merkitystä voimien palautumisessa pelkkään suoraan ompeluun verrattuna, mutta vammapuoli jäi 10–18 % heikommaksi verrattuna terveeseen jalkaan. Vammajalan akillesjänne oli 12 mm pidempi terveeseen jalkaan verrattuna. Vammajalan kolmipäisen pohjelihaksen tilavuus oli 11–13 % pienempi verrattuna terveeseen jalkaan. Akillesjänteen pituus korreloi pohjelihaksen voimapuolieron sekä pohjelihasatrofian kanssa. Akillesjännerepeämän leikkaushoidolla pohjelihaksen isokineettiset voimat palautuvat nopeammin ja täydellisemmin kuin konservatiivisella hoidolla. Leikkaushoitoon verrattuna konservatiivinen hoito johtaa suurempaan soleuslihaksen atrofiaan ja akillesjänteen pidentymään, mikä selittää osittain leikkaushoidon paremmat voimatulokset. 14 v seurannassa lihaskalvovahvikkeesta ei ole etua akillesjännerepeämän leikkaushoidossa. Akillesjännerepeämän leikkaushoidosta huolimatta potilaalle jää terveeseen jalkaan verrattuna 10–18 % pohjelihasten voimapuoliero. Akillesjänteen pidentyminen mahdollisesti selittää pohjelihasten atrofian, rasvadegeneraation ja pysyvän pohjelihasten voimapuolieron akillesjännerepeämän leikkaushoidon jälkeen 14 v seurannassa
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Kalhor, Roozbeh. "Accelerated Testing Method to Estimate the Lifetime of Polyethylene Pipes." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/79944.
Full textAbstract:
The ability to quickly develop predictions of the time-to-failure under different loading levels allows designers to choose the best polymeric material for a specific application. Additionally, it helps material producers to design, manufacture, test, and modify a polymeric material more rapidly. In the case of polymeric pipes, previous studies have shown that there are two possible time-dependent failure mechanisms corresponding to ductile and brittle failure. The ductile mechanism is evident at shorter times-to-failure and results from the stretching of the amorphous region under loading and the subsequent plastic deformation. Empirical results show that many high-performance polyethylene (PE) materials do not exhibit the brittle failure mechanism. Hence, it is critical to understand the ductile mechanism and find an approach to predict the corresponding times-to-failure using accelerated means. The aim of this study is to develop an innovative rupture lifetime acceleration protocol for PE pipes which is sensitive to the structure, orientation, and morphology changes introduced by changing processing conditions. To accomplish this task, custom fixtures are developed to admit tensile and hoop burst tests on PE pipes. A pressure modified Eyring flow equation is used to predict the rupture lifetime of PE pipes using the measured mechanical properties under axial tensile and hydrostatic pressure loading in different temperatures and strain rates. In total, the experimental method takes approximately one week to be completed and allows the prediction of pipe lifetimes for service lifetime in excess of 50 years.<br>Master of Science
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MaGee-Rodgers, Tamiko R. "Character Strengths of Nursing Home Administrators Who Lead Exemplary Long-Term Care." Thesis, Indiana Wesleyan University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10930255.
Full textAbstract:
<p> The growth in the older adult population will result in an increasing number of individuals with functional and cognitive limitations. The demand for nursing home administrators will grow proportionately with the aging population and the need for effective leadership within nursing homes is and will continue to be imperative as the population ages. Identifying top-rated nursing homes that provide quality care is essential to understanding the operations of successful long-term care facilities. Nursing home administrators (NHAs) are tasked with leading and directing provision of skilled, intermediate and rehabilitation care on a 24-hour basis while ensuring high quality operations. Identifying the character strengths of nursing home administrators who lead exemplary nursing homes may benefit other nursing home leaders who lead lower rated or underperforming facilities. In this qualitative study, 19 nursing home administrators who lead exemplary facilities across Indiana completed the Value in Action Inventory Strengths (VIA-IS) questionnaire and engaged in face-to-face interviews. Analysis of the interview data via NVivo indicated how the use of character strengths is crucial to effective leadership within long-term care. Creativity, fairness, bravery, perspective, and judgment were identified by a majority of study participants as essential to decisionmaking and problem solving, especially in a heavily regulated environment. Humor, hope, courage, and spirituality were acknowledged as contributing to a positive and optimistic environment. Humor, hope, courage, and spirituality were also noted as coping mechanisms when faced with stress and adversity. Honesty, kindness, love, teamwork, and gratitude were emphasized by the study participants as essential to relationship development and formation of trust with staff, residents, and families. This study allowed participants the opportunity to reflect on their own character strengths and leadership both personally and professionally. This reflection resulted in increased self-awareness and appreciation of their staff, residents, and roles as nursing home administrators. </p><p>
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Sá, Renata Bacelar Cantanhede de 1981. "Estudo da união dentina-sistemas adesivos que não contém HEMA = avaliação do selamento dentinário, micropermeabilidade e da resistência de união à dentina imediata e à longo prazo = Adhesion study of dentin-HEMA-free adhesive systems : evaluation of dentin sealing, micropermeability and immediately and long-term dentin bond strength." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287799.
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Orientador: Marcelo Giannini<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba<br>Made available in DSpace on 2018-08-28T03:49:14Z (GMT). No. of bitstreams: 1
Sa_RenataBacelarCantanhedede_D.pdf: 1663244 bytes, checksum: ddbd6a5d390052ef93aca63cbdf510ab (MD5)
Previous issue date: 2015<br>Resumo: Este estudo avaliou o efeito de agentes cross-linking e a utilização de sistemas adesivos (SA) que não contém o monômero HEMA. No capítulo 1 foram avaliadas a resistência de união (RU) e o selamento dentinário (SD) após 24 horas e 6 meses de armazenamento em água. Para RU, foram avaliados 4 SA: um autocondicionante e um convencional contendo o monômero HEMA (Scotchbond Universal/SU e Prime & Bond Elect/PB), um autocondicionante e um convencional sem HEMA (G-Aenial/GA e All-Bond 3/AB) respectivamente. Cada SA foi subdividido em grupos baseados na biomodificação da dentina: controle (sem aplicação de agentes cross-linking), glutaraldeído 5% e proantocianidina 6,5% (PA). Após a aplicação dos adesivos com ou sem o uso de agentes cross-linking e aplicação do compósito, os dentes foram seccionados para obtenção de espécimes, os quais foram avaliados com o teste de microtração. O agente cross-linking que produziu os melhores resultados (PA) foi selecionado para o estudo de SD. Os espécimes foram preparados da mesma forma como descrito anteriormente. As mensurações de permeabilidade dentinária (PD) foram realizadas com a simulação da pressão pulpar através de uma coluna de água de 140 cm em 5 tempos (PD mínima: P min, PD máxima: P máx, PD após o uso do PA: PPA, PD após aplicação dos SA: PSA e PD após 6 meses: Parmazenado). Para o grupo controle, a mensuração difere na remoção da etapa correspondente a PPA, continuando com PSA e Parmazenado, respectivamente. No capítulo 2 foram avaliadas a RU, SD e micropermeabilidade de 4 SA: um convencional contendo HEMA (Adper Single Bond 2/SB), um adesivo de 3 passos que não contem HEMA no solução adesiva hidrófoba (AB) e dois autocondicionantes sem HEMA (GA e BeautiBond/BB). Os dentes foram preparados da mesma forma descrita no primeiro capítulo. A micropermeabilidade foi avaliada através da infiltração do corante amarelo de lúcifer na camada híbrida. Todas as metodologias foram avaliadas após 24 horas e 1 ano de armazenamento em saliva artificial. As mensurações de SD foram expressas em %. Os dados foram analisados com metodologia de modelos mistos para medidas repetidas para o primeiro capítulo e ANOVA 2 fatores e teste de Tukey (?=0,05). A RU produzida por PB, SU e AB não apresentou diferença entre eles e GA apresentou os menores valores em 24 horas. Todos SA apresentaram maiores RU com a aplicação do agente cross-linking PA em 24 horas, independentemente de possuírem HEMA na composição. Após armazenamento por 6 meses, SU e AB apresentaram redução da RU. PA e SA reduziram a permeabilidade da dentina e da interface dentina-resina, respectivamente. No segundo capítulo, AB apresentou maior RU seguido de SB e dos autocondicionantes (BB e GA) em 24 horas. GA apresentou o menor valor de RU após um ano, pois teve redução com o armazenamento. No SD em 24 horas, SB e AB selaram a dentina como a Pmin, enquanto BB não apresentou a mesma capacidade, porém manteve-se estável por um ano. Na avaliação da micropermeabilidade, ausência do HEMA não influenciou os resultados. Os resultados sugerem que a aplicação apenas do agente cross-linking PA pode produzir o selamento da dentina e aumentar a RU. Na segunda parte do estudo, o adesivo AB mostrou os melhores resultados nas análises de RU, SD e micropermeabilidade<br>Abstract: This study evaluated the effects of cross-linking agents and adhesive systems (AS) that not contain the monomer HEMA. In the chapter 1 the microtensile bond strength (BS) and dentin sealing (DS) after 24 hours and 6 months of water storage were evaluated. For BS teste, 4 groups AS were evaluated: a self-etch and one total-etch HEMA-containing adhesives (Scotchbond Universal/SU and Prime & Bond Elect/PB), one self-etch and one total-etch HEMA-free adhesives (G-Aenial/GA and All-Bond 3/AB). Each AS was divided into sub-groups based on dentin biomodification: control (no cross-linking agent application), 5% glutaraldehyde and 6.5% proanthocyanidin (PA). After adhesives application with or not cross-linking agent use, teeth were sectioned to obtain specimens, which were evaluated in microtensile bond strength test. The most promising dentin biomodification strategy (PA) was selected for DS study. The specimens were prepared in the same way as previous described. Permeability (PD) measurements study was carried out using a simulated pulpal pressure of 140 cm water column at 5 times of evaluation (minimum PD: Pmin, maximum PD: Pmax, PD after PA: PPA, PD after AS application: PAS and PD after 6 months: Pstored). For the control group, the measurements differ from PPA removal, continuing with PAS and Pstored, respectively. In the chapter 2, BS, DS and micropermeability of 4 AS: one total-etch HEMA-containing (Adper Single Bond 2/SB), one three-step etch-and-rinse adhesive that does not contain HEMA in hydrophobic solution (AB) and two self-etch HEMA-free (GA and BeautiBond/BB). The teeth were prepared in the same way as described in the chapter one. For micropermeability analysis the yellow lucifer was used and detected its penetration into the hybrid layer. All methods were tested after 24 hours and after 1 year of artificial saliva storage. DS measurements were expressed as %. The data were submitted to multiple comparisons using PROC MIXED for chapter one and two-way ANOVA and by Tukey¿s test (?=0.05) for chapter two. The BS of PB, SU and AB did not differ among them and GA showed the lowest values at 24 hours. PA cross-linking agent increased the BS for all at 24 hours, regardless the presence of HEMA. Storage for 6 months significantly decreased the BS for SU and AB. PA and AS decrease the permeability of the dentin and dentin-resin interface, respectively. In the chapter two, AB showed the highest values BS followed by SB and self-etch adhesives (BB and GA) at 24 hours. GA showed the lowest BS after one year because it was reduced. For DS, SB and AB sealed the dentin as Pmin, while BB and did not present the same ability, however kept stable after one year. The micropermeability revealed that the absence of HEMA did not influence the outcomes. Results suggested that PA cross-linking application alone was able to seal the dentin and increase the BS. In the second chapter, AB adhesive showed the best results in BS, DS and micropermeability analyses<br>Doutorado<br>Materiais Dentarios<br>Doutora em Materiais Dentários<br>2011/11415-1, BEPE 2013/02386-3<br>FAPESP
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Büttner, Till, Allessandra Keil, Jeanette Orlowsky, and Michael Raupach. "Einsatz von Polymeren in Textilbeton – Entwicklung polymermodifizierter Betone und Einflüsse auf die Dauerhaftigkeit." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244045457582-60801.
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Die bei Textilbetonen überwiegend zum Einsatz kommenden Bewehrungen aus AR-Glas weisen infolge der Glaskorrosion einen signifikanten Tragfähigkeitsverlust auf. Im Rahmen des Teilprojektes D5 des SFB 532 wurden die Faktoren, die die Dauerhaftigkeit des Werkstoffes beeinflussen, evaluiert und in einen Modellansatz umgesetzt. Anhand dieser Untersuchungen konnten Möglichkeiten zur Reduktion des langfristigen Festigkeitsverlustes aufgezeigt werden. Eine dieser Möglichkeiten ist die Polymermodifikation des Betons, die im Wesentlichen einen Einfluss auf den Wassertransport innerhalb des Betonquerschnitts hat. Im Rahmen des Teilprojektes B4 des SFB 532 wurden polymermodifizierte Betone entwickelt und hinsichtlich ihres Wasseraufnahmeverhaltens untersucht. Im Anschluss wird die Wirkungsweise polymermodifizierter Betone hinsichtlich der Einflüsse auf die Dauerhaftigkeit von TRC beschrieben.
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Chaparro, Francisco Javier. "Biocompatible Electrospun Vehicles To Enhance the Effectiveness Of Anti-Fertility Strategies And Their Biomimetic Properties As Blood Vessel Scaffolds." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1514986344784852.
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McCullough, Kelly A. "Quality of life : its relationship to the identification and incorporation of life strengths in case management of long-term care clients." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1178342.
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The purpose of this study was to explore the effect an intervention, based on responses from a Life Strengths Interview questionnaire (LSI), has on the quality of life of elderly persons receiving private pay home care. A total of 12 subjects for this study were recruited from Cardinal Health Systems (CHS) Home Care service. This research employed a basic pretest posttest quasiexperimental design, with one experimental group and one control group. Subject selection was not randomized; however, subjects were randomly assigned to either the experimental or control group. Subjects in the experimental group completed the LSI pre-test and subjects in both groups completed the Quality of Life Index (QLI) pre-test and post-test, as well as a posttest care questionnaire. Data from eight subjects were coded and entered into a database; however, due to the small sample size, statistical analysis of responses from the QLI could not be performed. The primary thematic issues identified through qualitative data analysis indicate that home health aide services positively contribute to client quality of life, and that private-pay clients of CHS Homecare are currently satisfied with their quality of care. Qualitative results gathered by this study support future research efforts to explore the relationship between home care services and client quality of life. More specifically, this study can serve as a pilot for researchers interested in exploring the effects of a LSI intervention on clients receiving home care.<br>Fisher Institute for Wellness and Gerontology
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Савула, Р. С. "Забезпечення працездатності магістральних газопроводів в процесі тривалої експлуатації у гірській місцевості". Thesis, Івано-Франківський національний технічний університет нафти і газу, 2013. http://elar.nung.edu.ua/handle/123456789/4643.
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Дисертація присвячена дослідженням, спрямованим на забезпечення працездатності магістральних газопроводів в процесі тривалої експлуатації у гірській місцевості за рахунок удосконалення методів аналізу напружено-деформованого стану і оцінки міцності труб з урахуванням деградації матеріалу, відхилення від прямолінійності траси і наявності локальних пластичних деформацій. Досліджені структурні зміни, які відбуваються в сталях магістральних газопроводів в процесі тривалої експлуатації. Оцінено вплив процесів старіння трубної сталі та локальних пластичних деформацій магістральних газопроводів на фізико-механічні властивості експлуатованої сталі. Одержані кількісні оцінки механічних характеристик трубних сталей дають можливість уточнення допустимих умов експлуатації трубопроводів з урахуванням дії як технологічних, так і температурних навантажень. Проаналізовано процеси пружно-пластичного деформування труб під час укладання магістральних газопроводів у траншею на викривленій трасі і в процесі капітального ремонту ділянки трубопроводу з заміною котушки та визначені моменти, які повинні розвивати центрувальні пристрої. Досліджено вплив залишкових напружень, обумовлених локальним пластичним деформуванням магістрального трубопроводу, на напружено-деформований стан труби. Проведені експериментальні дослідження пружно-пластичного деформування і міцності труби в лабораторних умовах з метою перевірки допущень, прийнятих у теоретичних дослідженнях, а також вивчення закономірностей зміни коерцитивної сили трубної сталі 17ГІС в процесі експлуатації.<br>Диссертация посвящена исследованиям, направленным на обеспечение работоспособности магистральных газопроводов в процессе длительной эксплуатации в горной местности за счёт усовершенствования методов анализа напряжённо-деформированного состояния и оценки прочности труб с учётом деградации материала, отклонения от прямолинейности трассы и наличия локальных пластических деформаций. Исследованы структурные изменения, происходящие в сталях магистральных газопроводов в процессе длительной эксплуатации. Получили дальнейшее развитие экспериментальные исследования влияния длительной эксплуатации магистральных трубопроводов на физико-механические свойства трубных статей на основании проведения микроспектрального анализа материала и комплексных исследований характеристик прочности, пластичности, циклической трещиностой-кости, сопротивляемости сероводородному коррозионному растрескиванию под напряжением, водородом инициированного растрескивания, а также коррозионной стойкости стали. Изучена чувствительность микротвёрдости, склонности к водородом инициированного растрескивания, коррозионной стойкости, влияния сероводородной среды по отношению к статическим характеристикам прочности и пластичности длительно эксплуатированной трубной стали при налички локальных пластических деформаций. Получены количественные оценки механических характеристик трубных сталей дают возможность уточнения допустимых условий эксплуатации трубопроводов с учётом действия как технологических, так и температурных нагрузок.
Проанализированы процессы упругопластического деформирования труб во время укладки магистральных газопроводов в траншею на искривлённой трассе и в процессе капитального ремонта участка трубопровода с заменой катушки. Определены моменты, которые должны развивать центрирующие приспособления. Установлена зависимость между изгибающим моментом и кривизной оси трубы с учётом упрочнения материала в процессе упругопластического деформирования. Исследовано совместное влияние искривления оси трубопровода и изменения температуры на характеристики напряжённого состояния трубы. Исследовано влияние остаточных напряжений, обусловленных локальным пластическим деформированием магистрального трубопровода, на напряжённо-деформированное состояние трубы. Путём компьютерного моделирования локального упругопластического деформирования трубы как цилиндрической оболочки, взаимодействующей с шарообразным абсолютно твёрдым телом (индентором). установлено. что я центральной точке контакта индентора з трубой эквивалентное напряжение в материале, которое па начальном этапе деформирования трубы достигаег предела текучести, после приложения к трубе внутреннего давления уменьшается приблизительно в 1,5 раза. В го же время, напряжения на контуре вмятины, которые в процессе вдавливания индентора не достиг ают предела текучести, вследствие приложения внутреннего давления значительно возрастают и могут достичь предела текучести материала. Проведенные экспериментальные исследования упругопластического деформирования и прочности трубы в лабораторных условиях с целью проверки допущений, принятых в теоретических исследованиях, а также изучения закономерностей изменения коэрцитивной силы трубной стали 17ГІС в процессе эксплуатации. Усовершенствовано методику экспериментального определения напряжённо-деформированного состояния тела трубы с использованием неразрушающих магнитных методов и установлено влияние локальных пластических деформаций на прочность оболочечной конструкции.<br>The thesis is devoted to research, which is aimed at ensuring efficiency of gas main pipeline during long-term operation in the highlands by improving the methods of the stress-strain state analysis and strength assessment based on the degradation of pipe material, deviation from linearity route and the presence of local plastic deformation. The structural changes that occur in steel gas mains during prolonged use are researched. The effect of the tubular steel aging process and plastic deformations of local gas mains on physical and operated steel mechanical properties is estimated. The obtained quantitative estimates of the mechanical characteristics of steel pipe enable specification of acceptable conditions of pipelines in view of both process and temperature loads. The process of elastic-plastic deformation during pipe laying gas mains in a trench on the curved track is analysed, as well as during major repairs of pipeline replacement coil and defined points that should develop centering device. In this work is researched the influence of residual stresses due to local plastic pipeline deformation on the stress-strain pipe state. Experimental study of elastic-plastic deformation was held, as well as study of the tube strength in the laboratory to test the assumptions adopted in theoretical studies and the study of patterns of coercive strength change of tubular steel 17H IS during operation.
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Hodul, Jakub. "Vývoj speciálních sanačních hmot na beton pro extrémní namáhání s využitím druhotných surovin." Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-401596.
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The doctoral thesis deals with finding the use of some waste and secondary raw materials in the production of special polymer remediation materials for concrete, which could be applied even in constructions, where extreme mechanical and chemical load is occurred. The aim of this doctoral thesis is experimental examination of the possibility of using selected types of waste, including hazardous waste which represent the highest risk to environment, and secondary raw materials as a substitute for the currently used primary fillers in order to reduce the ecological footprint of the product itself. Some types of secondary raw materials, such as filter fly ash contaminated by flue gas denitrification process, are no longer used as a concrete admixture or partial cement substitution due to unwanted release of toxic ammonia (NH3). Mainly for this reason, the thesis deals with the progressive utilization of such types of secondary raw materials as well as with another currently unused waste into polymeric patching, grouting and anchoring materials while preserving or improving the final properties compared to reference materials using only primary raw materials. The result of this thesis is to find out suitable formulations for efficient preparation of special polymeric remediation materials for concrete containing waste and secondary raw materials as fillers. The partial aim of the thesis and a the scientific contribution is an observation of the developed materials internal structure using a modern device, CT tomography, an influence of the filler type on the long-term durability, and last but not least the observation of the rate of pollutants incorporation, found in hazardous waste, into the polymeric matric with the aid of EDX and FTIR analysis.
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Литвиненко, Тетяна Василівна. "The compaction of road embankment soils by ensuring their long-term strength." Thesis, 2016. http://er.nau.edu.ua/handle/NAU/22764.
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The thesis is devoted to improving the optimal compaction criteria of road embankment soils, which provide their long-term strength. The first unit contains the analysis of modern soil compaction methods, subgrade deformation causes in the embankment, finite element method (FEM) solves of soil compaction tasks, regulatory framework of quality control disadvantages, and others.
The second unit is stated a new author's method and the laboratory tests results of water migration in compacted silty loam embankment, including the stabilized (or final) clay soil moisture values, depending on their type (number plasticity), soil skeleton density, embankment height and time «rest» of the subgrade before it’s operation are presented. Water migration patterns in clay soil, placed in plastic tubes (it is simulated the soil multilayer consolidation of road embankment) through time is researched.
In the third unit as a result of statistical processing by least squares method the research laboratory and field data, the empirical dependence of compacted clay soil stabilized moisture for their multilayer consolidation in relation to soil skeleton density and plasticity number values is obtained. Empirical dependence parameter corresponds to maximum molecular moisture capacity at what it is advisable to do the subgrade clay soils multilayer consolidation for their long-term strength ensuring. The embankment thickness of multilayer consolidation and subgrade «rest» time after 2 months did not significantly affect the stabilized soil moisture.
In the fourth unit the field observation of clay soils compaction with multilayer rolling at five objects is performed. Full-scale experiment found that multilayer loams moisture consolidation by plastic limit of these soils during the «rest» time after subgrade erection and before its operation is reduced to a maximum molecular moisture capacity. General form of receiving from laboratory tests dependence of compacted loams stabilized moisture for their multilayer consolidation in relation to soil skeleton density in road embankment and plasticity number is approved.
The fifth unit contains the FEM modeling correct conditions of clay soils compaction process being a part of road embankments; suggestions for the optimal compaction criteria of road embankment soils; thesis results implementation. With high statistical indicators values the empirical equation of the relationship between clay soil skeleton density in each compacted layer and the initial clay soil skeleton density within the layer after its dumping and leveling, initial thickness of filled and planned to horizontal level subgrade by grader or bulldozer layer, reduction of each clay soil layer surface under the smooth roller is obtained.
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Shay, Barbara L. "Serotonin 5-HT2 receptors and mechanisms of long-term modulation of spinal reflex strength." 2003. http://hdl.handle.net/1993/20003.
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Ralho, Ana Catarina Loureiro. "Effect of long-term water aging on dentin bond strength of different adhesive systems." Master's thesis, 2019. http://hdl.handle.net/10316/89918.
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Trabalho Final do Mestrado Integrado em Medicina Dentária apresentado à Faculdade de Medicina<br>Introduction: The durability and stability of dentin adhesion in long term and after aging still remains questionable. In vitro models can simulate the aging of restorations and predict their durability. The goal of this study was to evaluate the effect of water aging on dentin bond strength comparing different adhesive systems after six years of storage.Materials and methods: Samples were prepared six years ago from 25 non-carious human molars. Dentin flat surfaces were obtained from these teeth which were sanded with sequence of silicon-carbide sandpaper to create a uniform smear layer. The teeth were randomly divided into five groups according to the adhesive systems used: Xeno® V+ (Dentsply DeTrey, Konstanz, Germany); Xeno® III (Dentsply DeTrey, Konstanz, Germany), Clearfil™ SE Bond (Kuraray Medical Inc., Okayama, Japan), OptiBond™ FL (Kerr, Orange, CA, USA) and Prime&Bond® NT (Dentsply DeTrey, Konstanz, Germany). The adhesive systems were applied according to the manufacturers' instructions and resin-composite build-ups were then applied. After being stored in distilled water at 37ºC, the samples were cut to obtain sticks. The samples were stored in water according to ISO/TS 11405:2015. Six years later, the sticks were tested in a tensile mode on a universal test machine at 0.5 mm/min. The data were analyzed by Kruskal Wallis test and a post-hoc pairwise comparison test using Bonferroni correction (p<0.05). The failure mode was also analyzed with an optical microscope.Results: Bond strength values increased from the Xeno® V+ (3.74±4.45 MPa), to Xeno® III (17.54±11.11 MPa), to ClearfilTM SE Bond (26.20±8.19 MPa), to Prime&Bond® NT (26.65±8.55 MPa) and to OptiBondTM FL (30.06±5.47 MPa), in this order. Etch-and-rinse and two-step self-etching adhesive systems registered higher bond strength, without statistically significant differences between them. Xeno® V+ generated very low bond strength with significant differences from all other groups. Adhesive failures were related with the lower bond strength values and cohesive failures with higher microtensile bond strengths.Conclusion: Etch-and-rinse and two-step self-etching adhesive systems presented high levels of dentin bond strength, after six years of water aging.<br>Introdução: Atualmente, a durabilidade e a estabilidade da adesão à dentina a longo prazo e após envelhecimento são ainda questionáveis. Modelos in vitro podem simular o envelhecimento de restaurações e prever a durabilidade da adesão. O objetivo deste estudo foi avaliar o efeito do envelhecimento em água na força de adesão à dentina, de diferentes sistemas adesivos. Materiais e métodos: As amostras foram preparadas há seis anos, a partir de 25 molares humanos não-cariados. Destes dentes foram obtidas superfícies planas de dentina que foram lixadas com uma sequência de lixas de carboneto de silício de diferentes grãos, para criar uma smear layer uniforme. Os dentes foram divididos aleatoriamente em cinco grupos de acordo com os sistemas adesivos utilizados: Xeno® V+ (Dentsply, DeTrey, Konstanz, Alemanha); Xeno® III (Dentsply, DeTrey, Konstanz, Alemanha); ClearfilTM SE Bond (Kuraray Medical Inc., Okayama, Japão), OptiBondTM FL (Kerr, Orange, CA, EUA) e Prime&Bond® NT (Dentsply, DeTrey, Konstanz, Alemanha). Os sistemas adesivos foram aplicados de acordo com o fabricante e, em seguida, as coroas dos dentes foram reconstruídas em resina composta. Depois de armazenadas em água destilada a 37ºC, as amostras foram cortadas para obter bastonetes. Os espécimes foram armazenados em água, de acordo com as normas ISO/TS 11405:2015. Seis anos depois, os bastonetes foram testados num modo de tração numa máquina de testes universal a 0,5 mm/min. Os dados foram analisados pelo teste de Kruskal Wallis e um teste de comparação post-hoc usando a correção de Bonferroni (p<0.05). O modo de falha foi também analisado com um microscópio ótico. Resultados: Os valores da força de adesão aumentaram do Xeno® V+ (3,74±4,45 MPa), para Xeno® III (17,54±11,11 MPa), ClearfilTM SE Bond (26,20±8,19 MPa), Prime&Bond® NT (26,65±8,55 MPa) e OptiBondTM FL (30,06±5,47 MPa), nesta ordem. Os sistemas adesivos total-etch e os self-etch de dois passos registaram maiores forças de adesão, no entanto, sem diferenças estatisticamente significativas entre eles. O Xeno® V+ gerou forças de adesão muito baixas, com diferenças significativas em relação aos outros grupos. Falhas adesivas foram relacionadas com menores valores de forças de adesão. Conclusão: Sistemas adesivos total-etch e self-etch de dois passos apresentaram valores de forças de adesão maiores, após seis anos de envelhecimento em água.
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Du, Plessis Louwrens Hermias. "The long term effects of chiropractic adjustment therapy on the activity and strength of the biceps brachii muscle." Thesis, 2014. http://hdl.handle.net/10210/9908.
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M.Tech. (Chiropractic)<br>Aim: The aim of this study was to determine the effects of chiropractic adjustment therapy (CAT) to the cervical spine on the reflex motorneuron excitability of C5 and C6 nerves on the biceps brachii muscle bilaterally. This study was also aimed at measuring the subsequent increase in strength of the biceps brachii muscle. Method: A selection of 30 participants, male or female and between the ages of 18 and 40 were recruited. Participants had to meet all the inclusion criteria and present with no contra-indications. Only one group was used as each participant served as their own control. Participants were seen seven times over a period of three weeks. The measurements were taken during the 1st, 4th and 7th consultations. On the 2nd, 3rd, 5th and 6th consultations only treatment was applied. On the 7th consultation only data was collected and no treatment was done. Results: Statistically significant improvement of dynamometry and electromyographic measurements were noted over the consultation periods on both sides. No conclusion could be made regarding the comparison of dynamometer and sEMG measurements of the biceps brachii between each consultation and between each side (left and right) over the study period. Conclusion: Based on the results obtained in this research it may be deduced that CAT may have an effect on the neurological system and further more an effect by increasing motorneuron excitability at sites distant to the spine itself. These results are important to the Chiropractic profession as it shows that CAT does not only produce a segmental response, but that there are wide spread effects on structures distant to the spinal column. The extent of the effects CAT can elicit on the nervous system requires further investigation.
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Wu, F. "Strategies to address the long-term maintenance of bone mineral density in younger women." Thesis, 2016. https://eprints.utas.edu.au/23445/2/Wu_whole_thesis_ex_pub_mat.pdf.
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Long-term maintenance of bone mineral density (BMD) in premenopausal women is critical to preventing osteoporosis and osteoporotic fractures. This thesis aimed to investigate potential strategies to optimise long-term bone health in younger women in a cohort of women who 12 years previously had participated in a 2-year randomised controlled trial (RCT) of an osteoporosis education intervention. In the original trial, women were randomised at baseline to receive group education (the Osteoporosis Prevention and Self-management course (OPSMC)) or an information leaflet. All women also received individualised feedback of either being or not being at higher risk of fracture in later life (high and normal risk groups). The risk was based on BMD measured by Dual-energy X-ray absorptiometry (DXA) according to whether or not each participant’s mean T-score at spine and hip was less than 0 (high and normal risk groups, respectively).
For this thesis, we performed a further 10-year follow-up, i.e. 12 years from baseline of the original RCT. We measured osteoporosis knowledge, self-efficacy, BMD at the femoral neck (FN) and lumbar spine (LS); calcium intake and calcium supplement use, physical activity and smoking status as in the original RCT. In addition, we measured serum 25-hydroxyvitamin D (25(OH)D), lower limb muscle strength (LMS), timed up and go test (TUG), functional reach test (FRT), lateral reach test (LRT) and step test (ST); total physical activity (accelerometer counts/minute of wear time), and time spent sedentary, in light and moderate-to-vigorous physical activity (MVPA).
Longitudinal data were used to investigate the long-term effects for the RCT interventions on BMD and osteoporosis preventive behaviours. Cross-sectional data were used to examine associations between the modifiable factors of vitamin D levels, LMS and physical activity and BMD and balance measures.
Key findings were:
Longitudinal data:
1. From baseline to 12 years, neither feedback of high fracture risk nor the OPSMC had an effect on the change in osteoporosis knowledge or self-efficacy.
2. From 2 to 12 years, the high fracture risk group had a smaller decrease in FN BMD (β=0.023 (95% CI: 0.005-0.042) g/cm²) but similar LS BMD change as the normal risk group. They also had a more favourable pattern of smoking behaviour change and were more likely to use calcium supplements and be recent users of vitamin D supplements. The OPSMC group had a more favourable pattern of smoking behaviour change compared to the leaflet group.
Cross-sectional data at 12 years:
3. There were significant cut-points for associations of 25(OH)D levels with FN BMD, LS BMD, TUG, ST, FRT and LMS (ranging from 29-33 nmol/L) but not LRT. Below these cut-points, there were beneficial associations between higher 25(OH)D level and each outcome while above the cut-points there were no beneficial associations.
4. Weaker LMS was associated with poorer performance on all balance tests. Significant cut-points of LMS were identified for all balance tests (29-50 kg) but excepting ST, these did not persist after excluding potentially influential data points.
5. Total physical activity was beneficially associated with FN BMD, LMS and TUG. MVPA was also beneficially associated with FN BMD, LMS, ST and TUG, and these associations (except for FN BMD) persisted after further adjusting for sedentary time. Sedentary time was detrimentally associated with TUG but not after further adjustment for MVPA.
In conclusion, feedback of high fracture risk to younger women was associated with long-term improvements in osteoporosis preventive behaviours and attenuated FN BMD loss and could be considered as a strategy to improve long-term bone health and prevent osteoporosis. Furthermore, we identified other potential strategies for maintaining BMD and balance in middle-aged women, namely:
• Maintaining adequate serum 25(OH)D noting that the current cut-off defining vitamin D deficiency of 50 nmol/L may be higher than needed for some musculoskeletal outcomes but appears warranted overall.
• Improving LMS.
• Increasing time spent in MVPA.
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Cheng, Wei-Kang, and 程維康. "The Influence of Bottom Ash Ratio and Cement Ratio on the Long-term Strength of Controlled Low Strength Material Using Trench Excavation Sandy Soils." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/60779442726753020798.
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碩士<br>朝陽科技大學<br>營建工程系碩士班<br>96<br>The research was conducted to investigate the short term (28 days) and long term (60 days) strength of the controlled low strength material (CLSM) using the re-cycled materials including the sandy soils from pipe trench excavation and bottom ash from furnace of power plants. The sandy soil from trench excavations was washed and sieved to exclude sizes larger than 3/8” before the specimens were prepared with parameters of selected water cement ratios (3.2, 2.7,2.18,1.71,1.41, and 1.1) and bottom ash ratios (0, 20, 40, 60, 80, and 100%).
The initial setting time of the CLSM specimens tested ranged from 12 to 36 hours which satisfy the specifications for the field operation. The results of the tests indicate that when the water cement ratio (w/c ratio) is less than 2.14, the 28-day strength of the CLSM increases more significantly up to 403% of that for w/c ratio=3.2. In addition, the 28-day strength reached the maximum when bottom ash ratio is around 50%, which is up to 141% of that for 0%bottom ash. This implies that decreasing the w/c ratio may be a main factor for increasing the short term strength of the CLSM, using the test results of w/c ratios of 2.7, 1.71 and 1.1 and bottom ash ratios of 60, 80 and 100%. The test results also indicated that the long term strength is still under development within 60 days with an increase from 3.9% to 29.95% of the 28-day strength. The significant long term strength development in some cases should be considered in the practical applications of the CLSM.
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Abela, MRL. "Exercising long-term : adherence to novel training modalities in older Australians - effects on strength, balance and functional capacity." Thesis, 2014. http://hdl.handle.net/10453/34520.
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University of Technology, Sydney. Faculty of Health.<br>NO FULL TEXT AVAILABLE. This thesis contains 3rd party copyright material. The hardcopy may be available for consultation at the UTS Library.<br>NO FULL TEXT AVAILABLE. This thesis contains 3rd party copyright material. ----- Age-related reductions in muscle strength, balance and functional capacity can be offset with exercise, however, whilst a plethora of exercise programs exist for older individuals, adherence is often poor. Understanding the types of exercise programs that appeal to older individuals, as well as the factors that predict exercise adherence was the rationale behind this thesis.
Study one investigated adherence between three types of home-based exercise programs, as well as identifying the predictors of exercise adherence among older individuals who were at an elevated risk of falling. Community-dwelling older adults aged >70 years (n=317) were recruited and divided into three groups consisting of gentle exercise (GE), structured strength and balance training (SSB) or a novel “unstructured” group that incorporated exercise into their daily lifestyle (LIFE). After six months of training, retention to the program was 81%, and overall adherence for the entire sample was 43%. Health status was the major predictor for non-adherence (OR=1.96, 95% CI=1.18-3.25) and other factors significantly associated with higher exercise adherence included parameters from biological, psychological, functional and behavioural domains. The LIFE and GE groups recorded significantly higher adherence (25.5%) compared to the SSB group and since the GE group was used as a control condition, it appears that the LIFE approach enhanced adherence to exercise in older adults.
Following the identification of numerous barriers to home-based exercise participation for older individuals and discovering that lifestyle programs can yield higher adherence, study two examined the effects of a novel form of training, Nintendo Wii Fit, on strength, balance and functional performance. This novel training regime was compared to a program which integrated exercise into daily life (IEDL) and was based upon the LIFE program in study one. The main outcome measures for this study included exercise adherence, strength, balance and functional performance. Nineteen community-dwelling women aged >70 years were recruited and randomised into the Wii group or the IEDL group. Following 10 weeks of training, adherence to the Wii Fit (88%) and IEDL (85%) groups was comparable. Additionally, the Wii Fit group displayed significantly higher balance confidence (17.3%) and knee extensor strength (33.1%) compared to the IEDL group. A number of improvements were recorded within the Wii Fit group for functional performance, knee flexion and extension strength and power, ankle dorsiflexion and static balance. Within-group improvements for similar parameters were recorded for the IEDL group, however, their magnitudes were often lower.
It appears that novel, home-based exercise programs can improve exercise adherence among older populations without compromising performance outcomes. The findings from this research provide allied health professionals with additional choices to traditional exercise programs for elderly populations.
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Balogun, SA. "Long-term risk factors for, and the impact of age-related muscle loss on the musculoskeletal health of older adults." Thesis, 2018. https://eprints.utas.edu.au/28678/1/Balogun_whole_thesis.pdf.
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Loss of skeletal muscle mass and function with ageing is a major public health concern with substantial financial implications. This thesis aims to examine the risk factors for age-related muscle changes over 10 years and the impact that these changes have on falls risk, fracture, mortality, and health-related quality of life (HRQoL) in community-dwelling older adults.
Data from a population-based sample of older adults aged 50–80 years (51% women; mean age 63±7.4 years) studied at baseline, 2.5, 5, and 10 years were analysed. Appendicular lean mass (ALM) and bone mineral density (BMD) were assessed by Dual-energy X-ray Absorptiometry (DXA). Handgrip strength (HGS) and lower-limb muscle strength (LMS) were measured using dynamometer, and muscle quality was calculated (muscle strength/muscle mass). Physical activity [steps/day] was assessed using a pedometer and the intensity of physical activity was measured using an accelerometer. Falls risk was measured using the Physiological Profile Assessment, fractures were self-reported and mortality was ascertained from the death registry. Serum 25-hydroxyvitamin D [25(OH)D] was assessed by radioimmunoassay, and HRQoL, knee pain and dysfunction were assessed using standardised questionnaires.
Traditionally, analysis has focused on examining how loss of muscle mass, strength and muscle quality differ between individuals (between-person comparison). Less well recognised is how variability in risk factors over time within the same individual (within-person comparison) are associated with muscle loss. The first study of this thesis described the longitudinal associations of between-person and a dynamic within-person variability in serum 25(OH)D, physical activity and knee pain and dysfunction with muscle mass, strength and muscle quality over 10 years. Both between-person and within-person increases in physical activity were associated with a higher muscle mass, strength and muscle quality. Within-person and between-person increases in knee pain and dysfunction were associated with a lower muscle strength and quality but not muscle mass. Between-person effects showed that higher average 25(OH)D was associated with higher 10-year average muscle mass, strength and muscle quality; whereas, within person increases in 25(OH)D was associated with a higher muscle strength and quality but not muscle mass.
The second study compared the performance of low muscle mass, muscle strength and muscle quality assessed at baseline with falls risk, incident fracture and mortality over 10 years. All baseline muscle strength and muscle quality measures were significantly associated with higher falls risk score at 10 years. Low handgrip and ALM/body mass index (BMI) were the only significant predictors of fracture and mortality respectively.
The third study described the longitudinal association of between-person and within-person variability in serum 25(OH)D, physical activity, knee pain and dysfunction with falls risk over 10 years. Knee pain and dysfunction above an individual’s usual level of pain increases the risk of falling, whereas, increasing one’s own moderate-to-vigorous physical activity level further reduced their risk of falling. Between-person but not within-person associations were observed between 25(OH)D and falls risk.
The fourth study examined the associations between low muscle mass, upper- and lower-limb muscle strength with HRQoL over 10 years. Participants with low LMS and low HGS (in women only) at baseline had a clinically meaningful difference in 10-year HRQoL compared to those with normal strength. There was a weaker but still significant association between low muscle mass and 10-year HRQoL.
The final study described the relationship between low muscle mass or strength, in the presence of osteopenia, with fracture and mortality risk. Incident fracture risk was significantly higher in participants with both osteopenia and dynapenia (osteodynapenia) compared to those without dynapenia or osteopenia. Mortality risk was significantly higher in participants with both osteopenia and sarcopenia (osteosarcopenia) compared to those without sarcopenia or osteopenia. However, osteosarcopenia and osteodynapenia did not lead to a significantly greater fracture or mortality risk compared to having these conditions on their own.
In conclusions, in addition to traditional between-person associations, variability in physical activity, 25(OH)D, knee pain and dysfunction within an individual over time relate to muscle changes and falls risk. Within-person effects were generally weaker compared to between-person estimates. Furthermore, muscle strength, which can be easily measured in clinical practice, appears more important than muscle mass for identifying individuals with a higher falls risk, fractures and poorer quality of life. However, muscle mass appears to be a better predictor of mortality risk. Low BMD combined with low muscle mass or strength does not significantly increase the risk of fracture or mortality compared to having low BMD or low muscle mass/strength alone, suggesting that combined assessments may not add additional risk for fracture and mortality.
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Gorash, Yevgen [Verfasser]. "Development of a creep damage model for non-isothermal long term strength analysis of high temperature components operating in a wide stress range / von Yevgen Gorash." 2008. http://d-nb.info/99468701X/34.
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CHIU, SHU-CHING, and 邱淑卿. "The Effectiveness of Chair Muscle Strength Training on Sarcopenic Obesity, Body Composition, Physical Performances, and Quality of Life among Sarcopenic Obese Residents in Long-term Care Facilities." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/65807343510119475062.
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博士<br>國立臺北護理健康大學<br>護理研究所<br>105<br>Background: With the arrival of an aging society, the issues of age-related sarcopenic obesity have become growing concerns. If this group of people can be assisted in reducing their aging rate and maintaining physical functions, then their quality of life can improve and the waste of social resources can decrease.
Purpose: This study explored the effectiveness of chair muscle strength training on sarcopenic obesity, body composition, physical performances, and quality of life among sarcopenic obese residents in long-term care facilities.
Methods: This study utilized a quasi-experimental research design. The subjects divided to 33 persons of experimental group and 31 people of comparison group. The experiment group implemented chair muscle strength training twice a week for 3 months compared with the control group that had usual care. We collected variables of body composition, physical performances (grip/pinch strength and daily living activity functions) and quality of life from before and after intervention among sarcopenic obese residents. The statistical methods uses were descriptive analysis, chi square, t test, generalized estimating equation (GEE), and difference-in-differences (DID).
Results: There were 64 participants of sarcopenic obesity, with a mean age of 79.52 (SD=7.74) years old and 54.7% were females. The finding showed that number of sarcopenic obese residents among experimental group decrseased 8.9% than comparison group after 3 months. The study employed GEE analysis for percentage skeletal muscle mass, and grouptime was non-significant (B=0.97, p>0.05); furthermore, analysis of the experiment group using DID showed significant improvement (B=0.95, p=0.035). On the other hand, after 3 months of training, grip strength (B=7.16, p=0.001) and pinch strength (B=1.46, p=0.014) exhibited a significant difference compared with the control group. The right grip strength of the experiment group increased 1.71kg (p=0.003) and the left grip strength improved 1.35kg (p=0.028) compared to the baseline. However, there were no statistical differences for the total scores of the functional independent measure, self-care, and general health with GEE grouptime analysis. Moreover, DID analysis discovered that the experiment group significantly increased those three scores 0.24, 2.76, and 1.73 points respectively, compared to the baseline (p<0.05). Finally, apart from age, gender, educational level, and the scores of Cumulative Illness Rating Scale (CIRS), the hand load level and the Borg rating scores both influenced the effect of a person’s total grip.
Conclusion: For institutional residents, 3 months of chair muscle strength training can increase grip and pinch strength. We suggest arranging activities of muscle strength training regularly among long-term care facilities elderly in order to maintain lean mass, physical functions, and quality of life.
Clinical Relevance: Regularly arranging twice a week chair muscle strength training is a beneficial activity for residents in long-term facilities. Grip strength is one master index for an effective outcome measurement to assess a sarcopenic obese person’s physical function.
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Comba, Lukáš. "Opravy kompozitních rekonstrukcí v prevenci ztrát zubních tkání. Dlouhodobá odolnost vazby kompozit-kompozit v různých prostředích." Doctoral thesis, 2020. http://www.nusl.cz/ntk/nusl-434924.
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in english Introduction: Composite restorations in the oral cavity are exposed to an aggressive environment and mechanical challenge that gradually impairs their physical and mechanical properties. This may result in an enhanced wear rate, loss of esthetic properties and an increased risk of a restoration fracture or its marginal failure with a negative impact on the restoration's durability. Worn or failed restorations are usually completely replaced, which increases the irreversible loss of dental hard tissues. Repair of composite restorations by their partial replacement is therefore a minimally invasive, preventive and less time-consuming alternative to their complete replacement and increases their longevity. In the oral cavity, the adhesive bond between the existing composite restoration and the repair composite resin is exposed to various chemical substances and mechanical stress, e.g. surfactants in toothpastes, which can initiate its degradation. By decreasing the surface tension, the penetration of water into the adhesive joint can be enhanced, accelerating the hydrolysis of the adhesive and reducing the composite repair strength. The major and not yet fully resolved issue of composite repairs is how to achieve a strong and durable bond between the existing and repair composite materials....