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A space $X$ is submaximal if any dense subset of $X$ is open. In this paper, we prove that every submaximal topological gyrogroup of non-measurable cardinality is strongly $\sigma$-discrete. Moreover, we prove that every submaximal strongly topological gyrogroup of non-measurable cardinality is hereditarily paracompact., Comment: 14 pages. arXiv admin note: text overlap with arXiv:2011.02633

In this study, the collapse-resistant performance of two, one-third scale composite beam–column substructures, with bolt and welded (WUF) connections and cover plate reinforced (WUFG) connections, were investigated by performing quasi-static tests. The experimental results demonstrated that the cover plate of the WUFG connections contributes to an increased displacement and bearing capacity in comparison with that of the WUF connections. Additionally, in comparison with the corresponding steel substructures, the maximum bearing capacities of the WUF and WUFG increased by approximately 18.0% and 19.9%, respectively. Multi-scale modeling method, which combined different types of elements with a reasonable connection, using the principle of displacement consistency, was calibrated by the experimental results. The results revealed that multi-scale models not only ensured the accuracy of the model calculation results, but also significantly improved the calculation efficiency. Based on the validated models, the influence of the surrounding members on the collapse-resistant performance of the composite beam–column substructure was analyzed. The results indicated that the axial constraint provided by the surrounding members demonstrated a greater impact on the collapse-resistant performance of the beam–column substructures in a certain range. Moreover, the multi-scale models were further extended to study the effect of important parameters on the collapse-resistant performance of the beam–column substructures, including the beam height, the beam span, the boundary condition, and the outermost column section, after which suitable ranges of these parameters were suggested.

Context Folium Ginkgo extract and tetramethylpyrazine sodium chloride injection (Xingxiong injection) is a compound preparation commonly used for treating cerebral ischaemia/reperfusion injury in ischaemic stroke in China. However, its potential mechanisms on ischaemic stroke remain unknown. Objective This study explores the potential mechanisms of Xingxiong injection in vivo or in vitro. Materials and methods Sprague-Dawley (SD) rats were randomly assigned to five groups: the sham (normal saline), the model (normal saline) and the Xingxiong injection groups (12.5, 25 or 50 mL/kg). The rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by reperfusion for 14 d. Xingxiong injection was administered via intraperitoneal (i.p.) injection immediately after ischaemia induction for 14 d. Afterwards, rats were sacrificed at 14 d induced by administration of Xingxiong injection. Results Xingxiong injection significantly reduces infarct volume (23%) and neurological deficit scores (93%) compared with the MCAO/R group. Additionally, Xingxiong injection inhibits the loss in mitochondrial membrane potential (43%) and reduces caspase-3 level (44%), decreases NOX (41%), protein carbonyl (29%), 4-HNE (40%) and 8-OhdG (41%) levels, inhibits the expression of inflammatory factors, such as TNF-α (26%), IL-1β (34%), IL-6 (39%), MCP-1 (36%), CD11a (41%) and ICAM-1 (43%). Moreover, Xingxiong injection can increase p-Akt/Akt (35%) and Nrf2 (47%) protein expression and inhibit NLRP3 (42%) protein expression. Conclusions Xingxiong injection prevents cerebral ischaemia/reperfusion injury via activating the Akt/Nrf2 pathway and inhibiting NLRP3 inflammasome. These findings provide experimental evidence for clinical use of drugs in the treatment of ischaemic stroke.

Cong Su,1,* Ting Wu,2,* Bao Meng,2 Chengcheng Yue,2 Yating Sun,2 Lingling He,2 Tingting Bian,2 Yanyan Liu,3,4 Ying Huang,5 Yanhu Lan,4 Jiabin Li2– 4,6 1Department of Infection Management, The First Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China; 2Department of Infectious Diseases, The First Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China; 3Anhui Center for Surveillance of Bacterial Resistance, Hefei, People’s Republic of China; 4Institute of Bacterial Resistance, Anhui Medical University, Hefei, People’s Republic of China; 5Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China; 6Department of Infectious Diseases, The Chaohu Hospital of Anhui Medical University, Hefei, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jiabin LiDepartment of Infectious Diseases, The First Affiliated Hospital and the Chaohu Hospital of Anhui Medical University, Jixi Road 218, Hefei, 230022, People’s Republic of ChinaEmail lijiabin@ahmu.edu.cnYanhu LanInstitute of Bacterial Resistance, Anhui Medical University, Jixi Road 218, Hefei, 230022, People’s Republic of ChinaEmail zixinhu@163.comBackground: Klebsiella pneumoniae (K. pneumoniae) causes community-acquired and hospital-acquired pneumonia. The mortality rates of invasive infections caused by hypervirulent K. pneumoniae (HvKP) are extremely high. However, the microbiological characteristics and clinical manifestations of K. pneumoniae in AnHui province still remain unclear.Purpose: To show the high prevalence of HvKP infections regarding clinical characteristics and antimicrobial resistance in Anhui province.Patients and Methods: A retrospective analysis was conducted to study the clinical data of 115 strains of K. pneumoniae from July 2019 to March 2020 in The First Affiliated Hospital of AnHui Medical University. The virulence genes, capsular types, carbapenemase genes, and molecular subtypes of these hypervirulent isolates were detected.Results: Overall, 59.1% (68/115) cases were HvKP infections, mainly from the department of intensive care unit (ICU, n=14, 20.6%) and the department of respiratory and critical care (n=13, 19.1%). K2 was the most prevalent capsular serotype (n=26), followed by K1 (n=21). The results of MLST identification of 68 strains showed that ST23 (n=15, 22.1%) was the most common type of ST, followed by ST11 and ST65 (n=12, 17.6%), ST86 (n=9, 13.2%), and ST412 (n=6, 8.8%). Among 68 hvKP strains, 12 isolates were carbapenem resistant, and all except two harboured KPC.Conclusion: The high incidence of carbapenemase producing HvKP in the Anhui province, especially the higher mortality of HvKP, should be paid more attention. Meanwhile, epidemiological surveillance and clinical treatment strategies should be continuously determined and implemented.Keywords: Klebsiella pneumoniae, virulence genes, capsular types, antimicrobial resistance

Local failure of one or more components due to abnormal loading can induce progressive collapse of a building structure. Herein, improved structural robustness is targeted to improve steel frame performance against progressive collapse. A multi-scale analysis model is constructed; then, the anti-collapse performance of a plane steel frame structure with a flush end plate connection is comprehensively analyzed using nonlinear static analysis. To enhance the anti-collapse capability of the steel frame structure, reasonable addition of infill panels in indirect- and direct-influence areas is proposed. Infill panels properly arranged in direct influence area can give full play to the Vierendeel mechanism, and effectively improve combined ability of the remaining structure. And then 1/8–1/6 of the net span is recommended as the length of the infill steel panel for the steel frame structure with flush end plate connection.

The rapid quantitative assessment of a structure’s resistance is critical to the structural design process in order to prevent the occurrence of progressive collapse. In this study, a three-bar component model of a top-seat angle with a double web angle connection was constructed based on the component method by dividing and simplifying its geometry. The proposed component model was then applied to a model of an unequal span substructure. An explicit calculation method and a numerical simulation method were proposed to describe the nonlinear static responses of the unequal span substructure under a scenario of interior column failure. These two methods were carefully validated against previously collected experimental data and were determined to accurately reflect the main responses of the structure, including the load–displacement relationship, development of internal forces, and deformation behaviour. The explicit calculation procedure, conducted using a step-by-step process in an Excel spreadsheet, was successfully applied to rapidly analyse and quantitatively evaluate the resistance of the unequal span steel substructure, which will lay the foundation for the resistance prediction and performance analysis of the whole structure against progressive collapse.

Background Intrauterine adhesion (IUA) is one of the leading causes of infertility and the main clinical challenge is the high recurrence rate. The key to solving this dilemma lies in elucidating the mechanisms of endometrial fibrosis. The aim of our team is to study the mechanism underlying intrauterine adhesion fibrosis and the origin of fibroblasts in the repair of endometrial fibrosis. Methods Our experimental study involving an animal model of intrauterine adhesion and detection of fibrosis-related molecules. The levels of molecular factors related to the endothelial-to-mesenchymal transition (EndMT) were examined in a rat model of intrauterine adhesion using immunofluorescence, immunohistochemistry, qPCR and Western blot analyses. Main outcome measures are levels of the endothelial marker CD31 and the mesenchymal markers alpha-smooth muscle actin (α-SMA) and vimentin. Results Immunofluorescence co-localization of CD31 and a-SMA showed that 14 days after moulding, double positive cells for CD31 and a-SMA could be clearly observed in the endometrium. Decreased CD31 levels and increased α-SMA and vimentin levels indicate that EndMT is involved in intrauterine adhesion fibrosis. Conclusions Endothelial cells promote the emergence of fibroblasts via the EndMT during the endometrial fibrosis of intrauterine adhesions.

Nicotinamide phosphoribosyltransferase (NAMPT) maintains mitochondrial function and protects against cerebral ischemic injury by improving energy metabolism. Notoginsenoside R1 (R1), a unique constituent of Panax notoginseng, has been shown to promote the proliferation and tube formation of human umbilical vein endothelial cells. Whether R1 has proangiogenesis on the activation of NAMPT in ischemic stroke remains unclear. The purpose of this study was to investigate the pharmacodynamic effect and mechanism of R1 on angiogenesis after ischemic stroke. We used male Sprague-Dawley (SD) rats subjected to middle cerebral artery occlusion/reperfusion (MCAO/R). R1 was administered via intraperitoneal (i.p.) injection immediately after ischemia induction. The promotion of R1 on angiogenesis were detected by immunofluorescence staining, 3D stereoscopic imaging and transmission electron microscopy detection. HBMEC cells were pretreated with different concentrations of R1 for 12 h before oxygen-glucose deprivation/reoxygenation (OGD/R) exposure. Afterward, scratch assay, EdU staining and tube formation were determined. Western blot analyses of proteins, including those involved in angiogenesis, NAMPT-SIRT1 cascade, VEGFR-2, and Notch signaling, were conducted. We showed that R1 significantly restored cerebral blood flow, improved mitochondrial energy metabolism and promoted angiogenesis. More importantly, incubation with 12.5-50 μM R1 significantly increased the migration, proliferation and tube formation of HBMECs in vitro. The promotion of R1 on angiogenesis were associated with the NAMPT-NAD