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The local structures and the g factors of two Cu2+ centers in YBa2Cu3O7–δ are theoretically studied by using the perturbation formulas of the g factors for a tetragonal and an orthorhombically elongated octahedral 3d9 clusters. The crystal-field parameters in these formulas are determined from the superposition model and the local distortions due to the Jahn–Teller effect. Based on the calculations, for the tetragonal Cu2+ center in YBa3Cu2O7, the Cu-O bonds are found to suffer the axial elongation of about 0.032 Å along the c-axis due to the Jahn–Teller effect. For the orthorhombic Cu2+ center in Y2BaCuO5, the Cu-O bonds is found to experience the axial elongation δZ (≈ 0.078 Å) along the c-axis and the planar bond length variation δX (≈ 0.012 Ǻ) in the perpendicular (ab) plane, responsible for the axial anisotropy Δg (= gz − (gx + gy)/2 = 0.168) and the perpendicular anisotropy δg (= gx – gy = 0.081). The theoretical g factors are in good agreement with the experimental data. The local structures of both Cu2+ centers are discussed. [ABSTRACT FROM AUTHOR]

Cold pilgering has been considered as the preferred rolling fabrication technology for difficult-to-deform tubular materials such as high-strength titanium alloy tubes. However, the tooling geometry may induce complex deformation and significantly influence crystallographic texture which is closely related to the dimension assuring and properties tailoring of tube products. In this study, taking high-strength Ti-3Al-2.5V tubes as the case material, the tooling design–related spatial deformation behaviors and crystallographic texture evolution of tube in cold pilgering are focused. A macro-meso scaled computation platform is established by combining the three-dimensional finite element (3D-FE) model with the viscoplastic self-consistent (VPSC) crystal plasticity model to predict both the inhomogeneous macrodeformation and microtexture evolution in cold pilgering. Two basic tooling parameters in pilgering, viz., E1 representing exponent of roller groove curve and mandrel curve and E2 representing exponent of groove clearance, are chosen as the design variables. The cold pilgering under different tooling parameters are simulated and analyzed. The results show that (1) The rolling force decreases with the increase of E1 , while the effect of E2 on the rolling force is not significant, and smaller E1 and larger E2 have advantage for preventing surface defects of the tube product; (2) The E1 of 2.8 and E2 of 2.0 are more conducive to the wall thinning–dominated deformation of tube; (3) Taking the contractile strain ratio (CSR) as an indicator for characterizing crystallographic texture–related mechanical properties, the appropriate values of E1 and E2 for desirable radial texture of tube product are obtained. [ABSTRACT FROM AUTHOR]

Purpose: To study the feasibility and clinical value of dynamic contrast-enhanced (DCE) computed tomography (CT) for early evaluation of targeted therapy efficacy in non-small cell lung cancer (NSCLC). Methods: We measured tumor diameter, peak height (PH), time to peak (TP), tumor mass-aortic peak height ratio (M/A), and blood perfusion (BP) in 20 patients with advanced NSCLC using DCE-CT before and 7 days after treatment. Therapy efficacy was assessed with conventional CT 4-6 weeks post-treatment. Results: Patients were grouped into those with partial response (PR), stable disease (SD), and progressive disease (PD) according to the therapy efficacy assessment at 4-6 weeks post-treatment. The PR group primary tumor diameter ( P = 0.0007) and BP ( P = 0.0225) were reduced at 7 days post-treatment; the SD group DCE-CT value changes were not significant. The PD group M/A ( P = 0.0443) and BP ( P = 0.0268) were increased 7 days post-treatment. The BP decrease group had significantly longer progression-free survival than the BP increase group (median, 54 vs. 6 weeks). Conclusion: DCE-CT can evaluate targeted therapy efficacy at 7 days post-treatment. Decreased primary tumor diameter and BP indicate tumor sensitivity to therapy; increased BP with unchanged tumor diameter suggests the tumor is not sensitive to therapy. Reduced BP suggests treatment effectiveness. [ABSTRACT FROM AUTHOR]

The in silico mapping (ISM) technique and its extension represent major advances for novel gene discovery in germplasm resources of inbred lines. However, the techniques suffer from a relatively high false-positive rate (FPR) and they do not consider the effect of linkage disequilibrium (LD) markers around the identified quantitative trait locus (QTL). In addition, it has not yet been established whether it is optimal to use absolute trait differences as the response variable. To address these problems, this article presents the multiple loci ISM (MLISM) approach, which uses all markers on the entire genome, along with a penalized maximum likelihood. The method proposed here was verified by a series of simulation experiments with a maize pedigree population of inbred lines of known ancestry. Results from the simulated studies show that the best response variable is the trait product. The MLISM FPR is substantially decreased and the proportion of the number of false QTL to the number of LD markers around the identified QTL is adequately reduced. The MLISM method, with the trait product as the response variable, is an improvement on the existing methods for novel QTL mapping in germplasm resources of inbred lines. [ABSTRACT FROM AUTHOR]