Anatomy of the pQCD Approach to the Baryonic Decays Λb→pπ,pK\Lambda_b \to p\pi, p K

We calculate the CP-averaged branching ratios and CP-violating asymmetries for the two-body charmless hadronic decays $\Lambda_b \to p \pi, pK$ in the perturbative QCD (pQCD) approach to lowest order in $\alpha_s$. The baryon distribution amplitudes involved in the factorization formulae are considered to the leading twist accuracy and the distribution amplitudes of the proton are expanded to the next-to-leading conformal spin (i.e., "P" -waves), the moments of which are determined from QCD sum rules. Our work shows that the contributions from the factorizable diagrams in $\Lambda_b \to p \pi, pK$ decays are much smaller compared to the non-factorizable diagrams in the conventional pQCD approach. We argue that this reflects the estimates of the $\Lambda_b \to p$ transition form factors in the $k_T$ factorization approach, which are found typically an order of magnitude smaller than those estimated in the light-cone sum rules and in the non-relativistic quark model. As an alternative, we adopt a hybrid pQCD approach, in which we compute the factorizable contributions with the $\Lambda_b \to p$ form factors taken from the light cone QCD sum rules. The non-factorizable diagrams are evaluated utilizing the conventional pQCD formalism which is free from the endpoint singularities. The predictions worked out here are confronted with the recently available data from the CDF collaboration on the branching ratios and the direct CP asymmetries for the decays $\Lambda_b \to p \pi$, and $\Lambda_b \to p K$. The asymmetry parameter $\alpha$ relevant for the anisotropic angular distribution of the emitted proton in the polarized $\Lambda_b$ baryon decays is also calculated for the two decay modes.Comment: 47 pages, 9 figures, 8 tables; typos and references corrected; version corresponds to the one accepted for publication in Phys. Rev.

The effect of anterior surgery for the patients with thoraclumbar-segment bursting fracture

目的  评价经前路手术治疗脊柱胸腰段爆裂性骨折的疗效。方法  对18例脊柱胸腰段爆裂性骨折的患者行前路手术治疗，手术后做6~48个月（平均14.6个月）的随访研究。结果  所有病例达到植骨融合，脊柱的高度、生理弧度恢复并保持较好，内固定无松动、断裂，除1例神经功能分级为A的患者神经功能没有明显恢复外，其他病例的神经功能都有1~3级的恢复。没有发生严重并发症的病例。结论  前路减压、植骨、内固定治疗脊柱胸腰段爆裂性骨折能彻底减压，充分植骨，稳定脊柱，有较好疗效。Obsjective: To evaluate the effect of anterior surgery for the patients with  thoraclumbar-segment bursting fracture. Methods: 13 patients with thoraclumbar-segment burstingfracture were treated through anterior surgery. After operation, the patients were followed-up for 6-24 months (average 15 months).According to Frankel’s grading of preoperation neurological lesions, 1 case was classified into A grade, 4cases into B grade, 8 cases into C grade, 4 cases into D grade, 1cases into Egrade. Results: All of the interbody autogenous strut graftings achieved solid fusion. The height and physiologic curve of vertebral column for all of the cases were recovered and maitained very well. Loosening and breaking for the internal fixations did not been found. Excepting the case of Frankel’s grade A, others achieved 1-3 grade recovering for nerve function. No serious complications were found. Conclusion: The treatment from anterior surgery for the patients with thoraclumbar-segment bursting fracture could achieve thorough decompressing, sufficient grafting-bone fusioning, stabling vertebral column and satisfactory outcome

Cross-View Hierarchy Network for Stereo Image Super-Resolution

Stereo image super-resolution aims to improve the quality of high-resolution stereo image pairs by exploiting complementary information across views. To attain superior performance, many methods have prioritized designing complex modules to fuse similar information across views, yet overlooking the importance of intra-view information for high-resolution reconstruction. It also leads to problems of wrong texture in recovered images. To address this issue, we explore the interdependencies between various hierarchies from intra-view and propose a novel method, named Cross-View-Hierarchy Network for Stereo Image Super-Resolution (CVHSSR). Specifically, we design a cross-hierarchy information mining block (CHIMB) that leverages channel attention and large kernel convolution attention to extract both global and local features from the intra-view, enabling the efficient restoration of accurate texture details. Additionally, a cross-view interaction module (CVIM) is proposed to fuse similar features from different views by utilizing cross-view attention mechanisms, effectively adapting to the binocular scene. Extensive experiments demonstrate the effectiveness of our method. CVHSSR achieves the best stereo image super-resolution performance than other state-of-the-art methods while using fewer parameters. The source code and pre-trained models are available at https://github.com/AlexZou14/CVHSSR.Comment: 10 pages, 7 figures, CVPRW, NTIRE202

Topological magnons in one-dimensional ferromagnetic Su-Schrieffer-Heeger model with anisotropic interaction

Topological magnons in a one-dimensional (1D) ferromagnetic (FM) Su-Schrieffer-Heeger (SSH) model with anisotropic exchange interactions are investigated. Apart from the inter-cellular isotropic Heisenberg interaction, the intercellular anisotropic exchange interactions, i.e. Dzyaloshinskii-Moriya interaction (DMI) and pseudo-dipolar interaction (PDI), also can induce the emergence of the non-trivial phase with two degenerate in-gap edge states separately localized at the two ends of the 1D chain, while the intracellular interactions instead unfavors the topological phase. The interplay among them has synergistic effects on the topological phase transition, very different from that in the two-dimensional (2D) ferromagnet. These results demonstrate that the 1D magnons possess rich topological phase diagrams distinctly different from the electronic version of the SSH model and even the 2D magnons. Due to the lower dimensional structural characteristics of this 1D topological magnonic system, the magnonic crystals can be constructed from bottom to top, which has important potential applications in the design of novel magnonic devices.Comment: 22 pages, 11 figure

CXCR4 Antagonist AMD3100 Modulates Claudin Expression and Intestinal Barrier Function in Experimental Colitis

Ulcerative colitis is a gastrointestinal disorder characterized by local inflammation and impaired epithelial barrier. Previous studies demonstrated that CXC chemokine receptor 4 (CXCR4) antagonists could reduce colonic inflammation and mucosal damage in dextran sulfate sodium (DSS)-induced colitis. Whether CXCR4 antagonist has action on intestinal barrier and the possible mechanism, is largely undefined. In the present study, the experimental colitis was induced by administration of 5% DSS for 7 days, and CXCR4 antagonist AMD3100 was administered intraperitoneally once daily during the study period. For in vitro study, HT-29/B6 colonic cells were treated with cytokines or AMD3100 for 24 h until assay. DSS-induced colitis was characterized by morphologic changes in mice. In AMD3100-treated mice, epithelial destruction, inflammatory infiltration, and submucosal edema were markedly reduced, and the disease activity index was also significantly decreased. Increased intestinal permeability in DSS-induced colitis was also significantly reduced by AMD3100. The expressions of colonic claudin-1, claudin-3, claudin-5, claudin-7 and claudin-8 were markedly decreased after DSS administration, whereas colonic claudin-2 expression was significantly decreased. Treatment with AMD3100 prevented all these changes. However, AMD3100 had no influence on claudin-3, claudin-5, claudin-7 and claudin-8 expression in HT-29/B6 cells. Cytokines as TNF-α, IL-6, and IFN-γ increased apoptosis and monolayer permeability, inhibited the wound-healing and the claudin-3, claudin-7 and claudin-8 expression in HT-29/B6 cells. We suggest that AMD3100 acted on colonic claudin expression and intestinal barrier function, at least partly, in a cytokine-dependent pathway