Plasma pH can be altered during pregnancy and at labor. Membrane excitability of smooth muscle including uterine muscle is suppressed by the activation of K+ channels. Because contractility of uterine muscle is regulated by extracellular pH and humoral factors, K+ conductance could be connected to factors regulating uterine contractility during pregnancy. Here, we showed that TASK-2 inhibitors such as quinidine, lidocaine, and extracellular acidosis produced contraction in uterine circular muscle of mouse. Furthermore, contractility was significantly increased in pregnant uterine circular muscle than that of non-pregnant muscle. These patterns were not changed even in the presence of tetraetylammonium (TEA) and 4-aminopyridine (4-AP). Finally, TASK-2 inhibitors induced strong myometrial contraction even in the presence of L-methionine, a known inhibitor of stretchactivated channels in myometrium. When compared to non-pregnant myometrium, pregnant myometrium showed increased immunohistochemical expression of TASK-2. Therefore, TASK-2, seems to play a key role during regulation of myometrial contractility in the pregnancy and provides new insight into preventing preterm delivery.

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Use of correct values of material properties is important in structural analysis. When incorrect values are used in the analysis, engineers may end up with misleading conclusions. The magnitudes of elastic modulus and strength are usually measured from experiments at room temperature. When these values are used in the thermal stress analysis of structures, the results may not be reliable because the magnitudes of elastic modulus and strength depend on temperature. The temperature distribution of HVAC (Heating, Ventilation and Air Conditioning) system was analyzed. The material properties were measured using MTS810 material test system and MTS 651 environmental chamber at different levels of temperature. They were used in the thermal stress analysis of HVAC system. It was found that the results of thermal stress analysis were significantly different from the results using material properties which were measured from experiments at room temperature.

Durability and reliability must be considered in the design of structural components. For this purpose, the failure probability is found using probabilistic analysis. A component in an automotive structure usually has many different designs depending on vehicle models. Even in the same vehicle model, the design of the component changes once in a few years. It is important to build up database so that engineers share knowledge in the design of components. The purpose of this study is to develop ontologies in the probabilistic analysis of structures. The ontologies can be used to capture and share knowledge for design process. They also help engineers make decisions on choosing appropriate software and algorithm for the probabilistic analysis of structures.

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