The objective of this research is the development of a new constitutive model to describe the behavior of cohesive soils under time dependent loading. In the work presented here, the modified SIMPLE DSS model is expanded to account for the effects of strain rate on clays in simple shear conditions. The response of clay soils is highly dependent on the rate of strain for both effective stress path and stress-strain behavior. The undrained shear strength is strongly influenced by strain rate both in monotonic and cyclic simple shear tests. Nevertheless, the few available experimental results cover a very limited range of loading conditions and rates. The existing literature established that the soil response display a unique relationship between shear strength and log scale of strain rate. To include the effects of strain rate, the modified simple effective stress model starts with two assumptions: (1) a specific shear strength corresponds to a specific strain rate in a unique relation; and (2) the effect of strain rate does not change the failure envelope. The proposed model is developed from the original SIMPLE DSS model, based on an effective stress formulation in a reduced stress space, and utilizing concepts related to the framework of bounding surface plasticity. The proposed model evaluationwas carried out comparing model simulations with results of simple shear tests on Boston Blue Clay and San Francisco Young Bay Mud. The model capability is useful especially in strain rate dependent responses for both monotonic and cyclic behavior, including irregular loading and step-changed condition. It was found that undrained shear strength in simple shear is directly related to strain rate effects and the responses in cyclic test show the more rate dependent behavior than those in monotonic test. The proposed model is able to predict the increase in undrained shear strength for higher strain rate.

Muscle strain injuries affect a wide range of physically active people around the world and are reaching epidemic proportions. Despite the variety of treatment options available in rehabilitation, there are no clear guidelines for electrical stimulation that provide effective reproducible results that address the underlying cause of these injuries. For instance, electrotherapy is inefficient at stimulating muscles, because of imprecise parameters and an ability to target particular muscles. The difference between this study and previous research is the precise delivery of electrical stimulation (intramuscular) at two different frequencies (2 Hz and 50 Hz) and comparing it a control group. Objective: To determine the difference on muscle strength and functional status between three treatments modalities for sub acute and chronic hamstring strains. Design: A randomized experimental design was used to compare the effects of low (2 Hz), high (50 Hz) and no-electrical (control) intramuscular stimulation on muscle strength and mental and functional status (AMSMC HEALTH STATUS INDEX). Each group consisted of 18 subjects. Main Outcome: The difference in treatment modalities was evaluated by comparing the muscle strength test (Biodex Dynamometer) results and the AMSMC HEALTH STATUS INDEX results in pretest and post-test conditions. Results: The AMSMC HEALTH STATUS INDEX, but not muscle strength test (Biodex), changed significantly after 2-Hz electrical intramuscular stimulation (pre-test µ = 66.56, Std= 11.92, post-test µ= 92.89, Std= 6.25), whereas no statistically significant changes in health status index and muscle strength test occurred with 50-Hz (pre-test = 69.22, Std= 11.31, post-test µ= 70.22, Std= 12.27)) and no-electrical stimulation groups (pre-test µ= 69.11, post-test µ= 73.39, Std= 13.18).

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Abstract There has been much interest in colossal magnetoresistance in doped maganite peroviskite meterials.(La,A)MnO3 thin film have been fabricated by off-axis RF magnetron sputtering techhique. The Growth mechanical of (La,A)MnO3 A=Ca,Sr in Different growth temperatures on substrate and different annealing temperatures reveals the observably different results on its structure and electrical transport properties. Due to the lattice mismatch between substrates and bulk,strain has been a important factors of magnetic resistance and electrical properties. Different thickness of La0.67Ca0.33MnO3 thin film were grown on (001)SrTiO3 and(001)MgO substrates at growth temperature 750 degree C ,it has shown systematic variations to film thickness in magnetic and electrical transport properties.

While it is clear that myocardium responds to mechanical stimuli, it is unknown whether myocytes transduce stress or strain. It is also unknown whether myofibers maintain lateral connectivity or move freely over one another when myocardium is deformed. Due to the lack of information about the relationship between macroscopic and cellular deformations, we sought to develop an experimental method to examine myocyte deformations and to determine their degree of affinity. A set of protocols was established for specimen preparation, image acquisition, and analysis, and two experiments were performed according to these methods. Results indicate that myocyte deformations are non-affine; therefore, some cellular rearrangement must occur when myocardium is stretched.

The objective of this research is the development of a new constitutive model to describe the behavior of cohesive soils under time dependent loading. In the work presented here, the modified SIMPLE DSS model is expanded to account for the effects of strain rate on clays in simple shear conditions. The response of clay soils is highly dependent on the rate of strain for both effective stress path and stress-strain behavior. The undrained shear strength is strongly influenced by strain rate both in monotonic and cyclic simple shear tests. Nevertheless, the few available experimental results cover a very limited range of loading conditions and rates. The existing literature established that the soil response display a unique relationship between shear strength and log scale of strain rate. To include the effects of strain rate, the modified simple effective stress model starts with two assumptions: (1) a specific shear strength corresponds to a specific strain rate in a unique relation; and (2) the effect of strain rate does not change the failure envelope. The proposed model is developed from the original SIMPLE DSS model, based on an effective stress formulation in a reduced stress space, and utilizing concepts related to the framework of bounding surface plasticity. The proposed model evaluationwas carried out comparing model simulations with results of simple shear tests on Boston Blue Clay and San Francisco Young Bay Mud. The model capability is useful especially in strain rate dependent responses for both monotonic and cyclic behavior, including irregular loading and step-changed condition. It was found that undrained shear strength in simple shear is directly related to strain rate effects and the responses in cyclic test show the more rate dependent behavior than those in monotonic test. The proposed model is able to predict the increase in undrained shear strength for higher strain rate.

The folded and thrusted Mesozoic clastic sequence of the Canadian Rocky Mountain foothills forms important hydrocarbon reservoirs. Understanding the distribution of natural fractures, their evolution, and timing of formation relative to the evolution of the fold-and-thrust system could potentially improve exploration and development outcomes in these otherwise tight unconventional reservoirs. However, the formation of fractures and their timing relative to folding and thrusting have remained unclear. I investigated the relation between folding and fracture formation in the Upper Cretaceous Cardium Sandstone by combining field structural observations and kinematic modeling of the fold-and-thrust belt evolution. I explored the relationship between fracture intensity and fracture strain with structural position by analyzing fracture spacing or frequency and aperture data collected along outcrop and micro-scanlines in the backlimb, in the forelimb close to the crest, and in the steeper dipping forelimb away from the crest of the Red Deer River anticline. Fracture frequency and aperture data collected both at the outcrop and micro scales indicate that variation in fracture strain is small across these three structural domains of the fold, with somewhat lower fracture intensity in the forelimb close to the crest. These fracture strain measurements are qualitatively consistent with calculated horizontal strain in the tectonic transport direction obtained through kinematic numerical models that simulate fold development associated with slip along the underlying Burnt Timber thrust. The models predict roughly similar amount of horizontal extension in both the back and forelimbs, and somewhat lower extension in the upper forelimb during early development of the Red Deer River anticline. Fracture formation early during fold development is consistent with the field structural observations of shear reactivation during later stages of folding. This combined kinematic modeling and field structural study demonstrates that deforming fold and thrust belts can undergo a complex evolution of bed-parallel extension in both space and time, resulting in spatially variable fracture formation in such structurally complex subsurface reservoirs. / text

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