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Simple Criterion (simple + criterion)
Selected AbstractsThe effect of interference-fit fasteners on the fatigue life of central hole specimensFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 7 2005A. LANCIOTTI ABSTRACT Fatigue tests were carried out on 2024-T351, thickness 1.6 mm, central hole specimens containing pins installed with five different interference-fit levels. Tests clearly demonstrated the beneficial effect of interference fit on fatigue resistance, up to the maximum value examined, 2.5%. A three-dimensional (3D) finite-element model was used in order to characterize the stress field around the hole. A large specimen, with a 40-mm-diameter hole filled with interference-fit pin, was instrumented by strain gauges and statically tested in order to check FEM results. A very good correlation existed between measured and numerically evaluated strains. FEM results demonstrated the well-known effect of interference-fit fasteners on reducing stress ranges. By increasing the interference level, the stress range was practically unchanged, while the mean stress decreased. Interference-fit produces a biaxial stress state, which must be taken into account for fatigue evaluation. In the present case, a simple criterion, based on hoop strain, predicted the fatigue results quite well with the exception of open hole fatigue test results, which were overestimated. [source] The Dependence of Crystal Structure of Te-Based Phase-Change Materials on the Number of Valence Electrons,ADVANCED MATERIALS, Issue 5 2004M. Luo A simple criterion to identify potential phase-change materials is developed using density functional theory. These compounds rely on the switching between an amorphous and a crystalline state. Here it is demonstrated that suitable alloys have an average valence electron number larger than 4.1 and show p-electron bonding leading to a six-fold coordination, while materials with a smaller number of valence electrons favor sp3 -bonding (see Figure). [source] Pathological prognostic score as a simple criterion to predict outcome in gastric carcinomaJOURNAL OF SURGICAL ONCOLOGY, Issue 1 2010Tadahiro Nozoe MD Abstract Purpose The aim of this study was to establish a simple criterion to predict prognosis of patients with gastric carcinoma. Methods Two hundred four patients with gastric carcinoma, who had been treated with curative resection, were enrolled. One point was added for each category among four pathological factors of depth of tumor, lymph node metastasis, venous invasion, and lymphatic invasion. Pathological Prognostic Score (PPS) was determined by an aggregate of these points for each category. Results There existed a significant difference between survivals of patients with PPS 0 or 1 and 2 or 3 (P,=,0.0002). Similarly, there also existed a significant difference between survivals of patients with PPS 2 or 3 and 4 (P,=,0.010). Conclusions PPS can be quite simple criteria to predict prognosis of gastric carcinoma with a strict stratification. J. Surg. Oncol. 2010;102:11,17. J. Surg. Oncol. 2010;102:73,76. © 2010 Wiley-Liss, Inc. [source] Thrombocytopenia: An important indicator for the application of partial exchange transfusion in polycythemic newborn infants?PEDIATRICS INTERNATIONAL, Issue 4 2000Betül Acunas Abstract Background: The conventional therapeutic approach in polycythemic newborn infants is to apply partial exchange transfusion (PET) when hematocrit value exceeds 70% or when the infant develops symptoms with the exception of plethora. Methods: In order to investigate the possibility of using platelet count as a simple criterion implying the PET requirement, we retrospectively reviewed polycythemic newborn infants with respect to the relationship between thrombocytopenia and severity of symptoms, and the association of platelet count and the PET performance. Thrombocytopenia has been defined as a platelet count <150 000/,L. Results: We studied 18 polycythemic infants with thrombocytopenia (group 1, 35%) and 34 without it (group 2, 65%). Perinatal asphyxia, gestational toxemia and intrauterine growth retardation, which are the three common causative factors leading to polycythemia, were not significantly different in the two groups. No correlation existed between platelet counts and hematocrit values within each group, but there was a very significant difference between the two groups in terms of severity of clinical findings (P<0001); no difference in terms of moderate findings and moderately significant difference with respect to mild symptoms and asymptomatic situation (P<0.05). Partial exchange transfusion was performed in all patients in group 1, while only 12 infants in group 2 (32%) received transfusion and the difference was statistically significant (P<0.05). A significant rise in platelet counts has been achieved only in group 1, while hematocrit values decreased significantly in both groups following PET. Conclusions: This study emphasizes the relationship between thrombocytopenia and the severity of clinical findings and PET performance rate in polycythaemic newborn infants, implying that thrombocytopenia is a possible marker of hyperviscosity, the results of which warrant further investigation. [source] Mechanical Deformation of Compressible Chromatographic ColumnsBIOTECHNOLOGY PROGRESS, Issue 3 2002R. N. Keener A one-dimensional model of mechanical deformation of compressible chromatography columns is presented. The model is based on linear elasticity and continuum mechanics and is compared to a more complete two-dimensional model and one-dimensional porosity profiles measured by NMR imaging methods. The model provides a quantitative description of compression and the effects of wall support during scale-up. A simple criterion for the significance of wall support as a function of both diameter and length is also developed. Although the model accounts only for mechanical deformation, flow compression can be included, and validation presented here suggests that a more complete model may be valuable for anticipating the effects of scale and aspect ratio on pressure-flow behavior of compressible columns. [source] | |||||||||||||