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In the paper, the eccentric compression behavior of the truss-reinforced cross-shaped concrete-filled steel tubular (CCFST) column is investigated. A total of eighteen CCFST columns were tested under eccentric compression, and the key test variables included the reinforced truss node spacing (s = 140 mm and 200 mm), slenderness ratio (λ = 9.2, 16.6, and 23.1), and eccentricity ratio (η = 0, 0.08, and 0.15). The failure mode, deformation characteristic, stress distribution, strain distribution at the mid-span of the steel tube, and the eccentric compression bearing capacity were assessed. The results show that due to the addition of reinforced truss, the steel plates near the mid-span of eccentrically compressed CCFST columns experienced multi-wave buckling rather than single-wave buckling after the peak load was reduced to 85%, and the failure mode of concrete also changed from single-section to multi-section collapse failure. Comparisons were made with the unstiffened specimen. The ductility coefficient of the stiffened specimen with eccentricity ratios of 0.08–0.15 and node spacings of 140 mm~200 mm increased by 70~83%, approaching that of the multi-cell specimens with an increasing steel ratio of 1.8%. In addition, by comparing the test results with the calculation results of four domestic and international design codes, it was found that the Chinese codes CECS159-2018 and GB50936-2014, and the Eurocode 4 (2004) can be better employed to predict the compression bearing capacity of truss-reinforced CCFST columns. [ABSTRACT FROM AUTHOR]

Background: Copper (Cu) homeostasis are important processes in the cause of metabolic diseases, but the association between Cu and obesity remains unclear. Methods: Participants were drawn from the 2011–2016 National Health and Nutrition Examination Survey (NHANES). Weighted logistic regression assessed the associations of serum Cu concentrations (tertiles) with obesity and central obesity in individuals without comorbidities. Obesity was defined as a BMI ≥30.0 kg/m2, and central obesity was defined as a waist circumference ≥80 cm for women and ≥95 cm for men. Results: This cross-sectional study included 1,665 adults without comorbidities, representing 24,744,034 people (mean age 35.1 years, 48.5% female). High serum Cu levels (tertile 3: ≥19.19 μmol/L) were associated with higher odds of obesity (adjusted odds ratio [OR]: 4.48, 95% CI[confidence interval]: 2.44–8.32) and central obesity (OR: 2.36, 95% CI: 1.19–4.66) compared to low serum Cu levels (tertile 1: ≤15.64 μmol/L). The dose-response curve showed a nonlinear association between Cu levels and obesity (P-nonlinear = 0.02) and a linear association with central obesity (P-nonlinear = 0.21). Conclusion: This study suggests that higher serum Cu levels are associated with increased odds of obesity in healthy American adults. [ABSTRACT FROM AUTHOR]

Anionic defects of H− (H∙O) and oxygen vacancies with trapped electrons (V∙O) have been built in the lattice of a hydrothermally derived perovskite (Ba5Nb4O15, BNO) by CaH2 reduction in Ar flow at 600 °C for 12 h. The formed anionic defects in the CaH2-reduced BNO (CaBNO) have been found to improve drastically the ammonia synthesis activity of Ru/CaBNO by donating electrons from both H∙O and/or V∙O to Ru atoms. The stoichiometry of H∙O and V∙O has been determined by TPR and TPO method, respectively. The H∙O defects have been proved to react with N2 under ammonia synthesis conditions via TPD, XPS measurements and isotope (D2) reaction, which provides secondary pathways for ammonia synthesis. Kinetic studies revealed that oxygen vacancies accept spilledover H atoms from Ru particles to alleviate the H2 poisoning effect. Cs-promoter has been demonstrated to accelerate the formation of anionic defects in CaBNO under ammonia synthesis reactions. Anionic defects (V∙O and H∙O) formed in the lattice of Ba5Nb4O15 perovskite via CaH2-reduction drastically promote the ammonia synthesis activity of Cs-Ru/CaBNO catalyst [ABSTRACT FROM AUTHOR]

Objective: To analyze the clinical effect of urokinase on the prevention of thrombosis in children with primary nephrotic syndrome. Methods: A total of 370 children diagnosed with primary nephrotic syndrome (PNS) in the Children's Hospital of Soochow University and Zibo Maternal and Child Health Hospital from January 2018 to December 2022 were selected as the research objects. The patients were divided into a urokinase adjuvant therapy group and non-urokinase adjuvant therapy group according to the application of drugs. The clinical data of the children were collected, including sex, age, drug application, bleeding during treatment, and telephone follow-up, to record whether thromboembolism occurred in the acute stage and remission stage. The clinical pattern of PNS, renal biopsy, histopathological type, and related laboratory indexes before and after treatment were recorded. Results: A total of 313 patients were treated with urokinase and 57 patients were not. More thrombotic events was observed in non-urokinase group compared to the urokinase group(2 versus 0 episodes, p = 0.02). The thrombotic events observed included one patient had pulmonary embolism combined with right ventricular thrombosis, and another had intracranial venous thrombosis. More minor bleeding events occurred in urokinase group compared to the non-urokinase group(7 versus 1 episodes, p = 1.0). No major bleeding events occurred in either group. Conclusion: The rational prophylactic use of urokinase anticoagulation in children with PNS can prevent the formation of thromboembolism and has good safety. [ABSTRACT FROM AUTHOR]

In order to avoid joint failure of half grouted sleeve connection due to bond-slip, a method of applying the anchor plate in half grouted sleeve is proposed to improve reliability and mechanical properties of half-grouted sleeve connection. Using the ABAQUS software, considering the bond-slip between the steel bar and the grouting material and the plastic damage of the grouting material, a finite element simulation specimen group with different diameters of steel bars and with or without anchor plates is set up, and the specimen group is monotonically carried out by means of displacement loading. The results show that the bond strength between steel bar and grout increases and the elongation displacement of half grouted sleeve connection decreases with the increase of anchorage length of steel bar under the same diameter. Under the same length of anchorage, with the increase of steel bar diameter, the relative slip between steel bar and grouting material increases, and the elongation displacement of half grouted sleeve connection increases. At the same time, the restriction effect is more obvious with additional anchor plate. Adding the anchor plate avoids the pull-out failure mode of steel bar when the anchorage length of steel bar is equal or less than 8d (d is the diameter of steel bar). The bonding action range of steel bar-grout interface without anchor plate connection is limited. The anchor plate plays a bearing role, and the stress of the steel bar on the side away from the load end is significantly reduced. Therefore, the performance of half grouted sleeve connections can be improved by means of anchor plates. [ABSTRACT FROM AUTHOR]

To improve the concrete confinement and mechanical properties of concrete-filled steel tube (CFST) columns, a new configuration of steel-tube-confined concrete-filled steel tube (T-CFST) columns has recently been developed, in which an outer steel tube is employed externally, and the additional tube does not sustain the axial load directly. This preliminary experimental study revealed that, due to the effective concrete confinement by the outer steel tube, the T-CFST column achieves higher compressive strength and more ductile deformation compared to the CFST columns of the same steel ratio. In this study, two finite element (FE) models were developed for the T-CFST cross-section and stub column, respectively. The numerical study results revealed that the concrete can be constrained by the outer steel tube at the beginning of loading and the outer steel tube hoop stress can reach its yield strength at the column's compressive strength, showing its effective confinement to the concrete. Numerous data were generated by the developed FE model to cover a wide range of parameters. Based on that, the calculation methods for the stress components of the inner and outer steel tubes are proposed. Finally, a suitable prediction method is proposed, utilizing the superposition method to determine the compressive strength of the T-CFST stub column, and the results of the calculation method and FE model agree well with each other. This research is the basis for promoting further research of T-CFST columns. [ABSTRACT FROM AUTHOR]

Anionic defects of H− (H∙O) and oxygen vacancies with trapped electrons (V∙O) have been built in the lattice of a hydrothermally derived perovskite (Ba5Nb4O15, BNO) by CaH2 reduction in Ar flow at 600 °C for 12 h. The formed anionic defects in the CaH2-reduced BNO (CaBNO) have been found to improve drastically the ammonia synthesis activity of Ru/CaBNO by donating electrons from both H∙O and/or V∙O to Ru atoms. The stoichiometry of H∙O and V∙O has been determined by TPR and TPO method, respectively. The H∙O defects have been proved to react with N2 under ammonia synthesis conditions via TPD, XPS measurements and isotope (D2) reaction, which provides secondary pathways for ammonia synthesis. Kinetic studies revealed that oxygen vacancies accept spilledover H atoms from Ru particles to alleviate the H2 poisoning effect. Cs-promoter has been demonstrated to accelerate the formation of anionic defects in CaBNO under ammonia synthesis reactions. Anionic defects (V∙O and H∙O) formed in the lattice of Ba5Nb4O15 perovskite via CaH2-reduction drastically promote the ammonia synthesis activity of Cs-Ru/CaBNO catalyst [ABSTRACT FROM AUTHOR]

Background: Immunoglobulin A vasculitis with nephritis (IgAVN) is the most common vasculitis in children. Due to a lack of evidence, treatment recommendations are based on expert opinion, resulting in variation. The aim of this study was to describe the clinical presentation, treatment and outcome of an extremely large cohort of children with biopsy-proven IgAVN in order to identify prognostic risk factors and signals of treatment efficacy., Methods: Retrospective data were collected on 1148 children with biopsy-proven IgAVN between 2005 and 2019 from 41 international paediatric nephrology centres across 25 countries and analysed using multivariate analysis. The primary outcome was estimated glomerular filtration rate (eGFR) and persistent proteinuria at last follow-up., Results: The median follow-up was 3.7 years (interquartile range 2-6.2). At last follow-up, 29% of patients had an eGFR <90 mL/min/1.73 m2, 36% had proteinuria and 3% had chronic kidney disease stage 4-5. Older age, lower eGFR at onset, hypertension and histological features of tubular atrophy and segmental sclerosis were predictors of poor outcome. There was no evidence to support any specific second-line immunosuppressive regimen being superior to others, even when further analysing subgroups of children with reduced kidney function, nephrotic syndrome or hypoalbuminemia at onset. Delayed start of immunosuppressive treatment was associated with a lower eGFR at last follow-up., Conclusion: In this large retrospective cohort, key features associated with disease outcome are highlighted. Importantly, there was no evidence to support that any specific immunosuppressive treatments were superior to others. Further discovery science and well-conducted clinical trials are needed to define accurate treatment and improve outcomes of IgAVN., (© The Author(s) 2024. Published by Oxford University Press on behalf of the ERA.)