Cold metal forming processes have been widely used for manufacturing of their high production rates and increased yield strength after forming process. For the use in service, increased yield strength of the cold-formed products should be known. The new yield strength can be found by several methods. Mechanical tests such as compression or tensile test are direct methods to obtain new yield strength if the product shape is appropriate. Finite element simulations may be another way to get accurate results for new yield strength distribution. Also Vickers hardness number can be used for prediction of yield strengths by available conversion models. The aim of this study is to compare the results of all these methods. During the study two different materials (austenitic stainless steel and carbon steel) cold formed by drawing and extrusion are investigated. FE simulations have been conducted to predict product properties. For this purpose flow curves obtained from compression and tensile tests are used in FE-models based on elasto-plastic, isotropic hardening material. Results show that both materials are highly anisotropic and have much lower yield strength values than found in simulations. Similarly none of the models correlating Vickers hardness numbers and yield strengths are successful since they are designed for an isotropic hardening material. This study basically presents the deviation of a real material behavior from isotropic material behavior.

A fécula de açafrão (Curcuma longa L.) apresenta grande potencial para a indústria de alimentos, pois está presente em abundância nos rizomas do açafrão, podendo assim, ser considerada uma fonte alternativa aos amidos já comercializados. Muitos amidos tem passado por modificações físicas, como a aplicação da irradiação gama, para que este adquira novas características e aumente sua aplicabilidade. O objetivo desta pesquisa foi estudar a influência de diferentes doses de radiação sobre a fécula de açafrão (Curcuma longa L.) e avaliar sua aplicação tecnológica em bolo de cenoura. A composição centesimal não foi influenciada significativamente pelas doses de radiação. No entanto, a textura dos géis foi afetada, bem como as soluções gelatinizadas. A solução não gelatinizada apresentou comportamento dilatante e a gelatinizada foi caracterizada como pseudoplástica. Em relação a substituição parcial da farinha de trigo pela fécula de açafrão sob todas as doses estudadas, o resultado se mostrou viável na elaboração do bolo de cenoura, indicando que esta fécula pode ser aplicada em diversos alimentos, sem provocar a rejeição do produto final. / The saffron starch (Curcuma longa L.) presents great potential for the food industry, as it is present in abundance in the saffron rhizomes, and can therefore be considered an alternative source to already commercialized starches. Many starches have undergone physical modifications, such as the application of gamma irradiation, so that it acquires new characteristics and increases its applicability. The objective of this research was to study the influence of different doses of radiation on safflower starch (Curcuma longa L.) and to evaluate its technological application in carrot cake. The centesimal composition was not significantly influenced by radiation doses. However, the texture of the gels was affected, as well as the gelatinized solutions. The non-gelatinized solution presented dilating behavior and the gelatinized solution was characterized as pseudoplastic. Regarding the partial substitution of wheat flour for saffron starch under all doses studied, the result was viable in the preparation of the carrot cake, indicating that this starch can be applied in several foods without causing the rejection of the final product.

Indiana University-Purdue University Indianapolis (IUPUI) / Peripheral arterial disease is caused by plaque buildup in the peripheral arteries. Standard treatments are available when the blockage is proximal and focal, however when distal and diffuse the same type of the treatment options are not beneficial due to the diseased locations. Restoration of blood flow and further salvaging of the limb in these patients can occur in a retrograde manner through the venous system, called retroperfusion or arteriovenous reversal. Retroperfusion has been explored over the last century, where early side to side artery to venous connections had issues with valve competency prohibiting distal flows, edema buildup, and heart failure. However, more recent clinical studies create a bypass to a foot vein to ensure distal flows, and though the results have been promising, it requires a lengthy invasive procedure. It is our belief that the concerns of both retroperfusion approaches can be overcome in a minimally invasive/catheter based approach in which the catheter is engineered to a specific resistance that avoids edema and the perfusion location allows for valves to be passable and flow to reach distally. In this approach, the pressure flow relations were characterized in the retroperfused venous system in ex-vivo canine legs to locate the optimal perfusion location followed by in-vivo validation of canines. Six canines were acutely injured for 1-3 hours by surgical ligation of the terminal aorta and both external iliac arteries. Retroperfusion was successfully performed on five of the dogs at the venous popliteal bifurcation for approximately one hour, where flow rates at peak pressures reached near half of forward flow (37±3 vs. 84±27ml/min) and from which the slope of the P/F curves displayed a retro venous vasculature resistance that was used to calculate the optimal catheter resistance. To assess differences in regional perfusion, microspheres were passed during retroperfusion and compared to baseline microspheres passed arterially prior to occlusion in which the ratio of retroperfusion and forward perfusion levels were near the ratio of reversed and forward venous flow (0.44) throughout the limb. Decreases in critical metabolites during injury trended towards normal levels post-retroperfusion. By identifying the popliteal bifurication as a perfusion site to restore blood flow in the entirety of the distal ischemic limb, showing reversal of injury, and knowing what catheter resistances to target for further chronic studies, steps towards controlled retroperfusion and thus more efficient treatment options can be made for severe PAD patients.