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Abstract: This paper is concerned with the extrapolation algorithm of Numerov''s scheme for semilinear and strongly nonlinear two-point boundary value problems. The asymptotic error expansion of the solution of Numerov''s scheme is obtained. Based on the asymptotic error expansion, Richardson''s extrapolation is constructed, and so the accuracy of the numerical solution is greatly increased. Numerical results are presented to demonstrate the efficiency of the extrapolation algorithm. [Copyright &y& Elsevier]

This paper is concerned with a numerical method for the time-fractional Benjamin–Bona–Mahony (BBM) equation whose solution typically exhibits a weak singularity at the initial time. Lyu and Vong (2019) presented a linearized difference method of second-order in space and third-order in time. We improve their result by proposing a linearized and compact difference method which is fourth-order in space while keeping third-order in time. By using discrete energy analysis, the unconditional convergence of the proposed method is rigorously proved and the optimal H 1 -norm error estimate is obtained. Numerical results confirm the theoretical convergence result. [ABSTRACT FROM AUTHOR]

The electronic properties in particular the occupation number of 5f electrons and the valence state of Am ions in americium trichloride (AmCl3) are studied by using density functional theory (DFT) merged with dynamical mean‐field theory (DMFT). We find that j = 5/2, j = 7/2 manifolds both are in the insulating regimes, resulting in the semiconducting band gap of about 0.837 eV, together with the weak Am 5f‐conduction electrons hybridization and the localized 5f‐derived spectra feature in the vicinity of the Fermi level. The weighted summation for the occupation probabilities of 5fn (n = 3–7) atomic configurations suggests that 5f electrons have the inter‐configuration fluctuation with an average occupation number of 5f electrons n5f ~ 5.182, corresponding to the valence state of Am3.818+ in AmCl3. The 5fn‐mixing‐driven inter‐configuration fluctuation might originate from the complicated quantum mechanics processes such as the dual nature of 5f electrons and the flexible electronic configuration of Am ions. Finally, the so‐called quasiparticle band structure is also predicted. [ABSTRACT FROM AUTHOR]

Aims: The influence of the moss layer on soil structure and soil water retention is not well understood. Therefore, this study aims to investigate the changes in soil structure and soil water retention under moss layer and to reveal the influencing factors of these changes. Methods: 3D networks of moss layer and soil macropores were quantified using CT scanning and image analysis techniques, and soil water retention characteristics were explored through soil water retention curves (SWRCs) and VG model. Results: The length densities of the soil macropores under the thin moss and thick moss layers were approximately 2.7 and 1.6 times higher than that under no moss cover. The soil water retention under the thin and thick moss layers were greater than those under no moss cover, with the highest plant-available water capacity under the thin moss layer. The maximum water-holding capacity of the moss layer was significantly positively correlated with the field water-holding capacity of the soil and negatively correlated with the equivalent diameter of the macropores, while the storage capacity of the moss layer was significantly and negatively correlated with the maximum effective water content of the soil. The field capacity (FC) and permanent wilting point (PWP) were significantly and positively correlated with the soil organic matter. Conclusions: The effect of the moss layer on water retention may be mainly realized by influencing the pore distribution and organic matter accumulation. The moss layer had a positive ecohydrological effect on soil water retention and even water conservation in forest soils. [ABSTRACT FROM AUTHOR]

Previous studies found cDC1s to be protective in early stage anti-GBM disease through Tregs, but pathogenic in late stage Adriamycin nephropathy through CD8+ T cells. Flt3 ligand is a growth factor essential for cDC1 development and Flt3 inhibitors are currently used for cancer treatment. We conducted this study to clarify the role and mechanisms of effects of cDC1s at different time points in anti-GBM disease. In addition, we aimed to utilize drug repurposing of Flt3 inhibitors to target cDC1s as a treatment of anti-GBM disease. We found that in human anti-GBM disease, the number of cDC1s increased significantly, proportionally more than cDC2s. The number of CD8+ T cells also increased significantly and their number correlated with cDC1 number. In XCR1-DTR mice, late (day 12–21) but not early (day 3–12) depletion of cDC1s attenuated kidney injury in mice with anti-GBM disease. cDC1s separated from kidneys of anti-GBM disease mice were found to have a pro-inflammatory phenotype (i.e. express high level of IL-6, IL-12 and IL-23) in late but not early stage. In the late depletion model, the number of CD8+ T cells was also reduced, but not Tregs. CD8+ T cells separated from kidneys of anti-GBM disease mice expressed high levels of cytotoxic molecules (granzyme B and perforin) and inflammatory cytokines (TNF-α and IFN-γ), and their expression reduced significantly after cDC1 depletion with diphtheria toxin. These findings were reproduced using a Flt3 inhibitor in wild type mice. Therefore, cDC1s are pathogenic in anti-GBM disease through activation of CD8+ T cells. Flt3 inhibition successfully attenuated kidney injury through depletion of cDC1s. Repurposing Flt3 inhibitors has potential as a novel therapeutic strategy for anti-GBM disease. • cDC1s are pathogenic in anti-GBM disease through activating CD8+ T cells. • Flt3 inhibitor depleted cDC1s selectively, resulting in attenuation of kidney injury. • Flt3 inhibition is a novel therapy for anti-GBM disease, with accelerated translational potential through drug repurposing. [ABSTRACT FROM AUTHOR]

Beidou is the regional satellite navigation system in China, consisting of three kinds of orbiting satellites, MEO, GEO and IGSO, with the orbital altitudes of 21500-36000km. For improving the accuracy of satellites orbit determination, calibrating microwave measuring techniques and providing better navigation service, all Beidou satellites are equipped with laser retro-reflector arrays (LRAs) to implement high precision laser ranging. The paper presents the design of LRAs for Beidou navigation satellites and the method of inclined installation of LRAs for GEO satellites to increase the effective reflective areas for the regional ground stations. By using the SLR system, the observations for Beidou satellites demonstrated a precision of centimeters. The performances of these LRAs on Beidou satellites are very excellent. [ABSTRACT FROM AUTHOR]

The electronic properties, in particular, the occupation number of 5f electrons and the valence state of U ions in uranium sesquinitride (U 2 N 3 ) are studied by using density functional theory (DFT) calculations merged with dynamical mean-field theory (DMFT). The results demonstrate that j=5/2 and j=7/2 manifolds are in the weakly correlated metallic and weakly correlated insulating regimes, respectively. The quasi-particle weights indicate that LS coupling scheme is more feasible for 5f electrons, which are not in the orbital-selective localized state. The weighted summation of the occupation probabilities of 5f n (n=0,1,2,3,4) atomic configurations suggests that 5f electrons have the inter-configuration fluctuation, or the mixed-valence state for U ions, together with an average occupation number of 5f electrons n 5f ∼2.234, which is in good agreement with the electron localization function (ELF) and occupation analysis based on other DFT-based calculations. The 5f n -mixing-driven inter-configuration fluctuation might originate from the dual nature of 5f electrons, and the flexible electronic configuration of U ions. Finally, the so-called quasiparticle band structure is also discussed., (© 2023 Wiley-VCH GmbH.)

Purpose: To investigate the effect of microRNA-125b (miR-125b) on osteogenic differentiation of periodontal ligament stem cell (PDLSCs)., Methods: The surface factor of isolated PDLSCs was detected by flow cytometry. After transfected with miR-125b or anti-miR125b in PDLSCs, MTT and LDH were used to detect cell viability and cytotoxicity; ALP activity and calcium level were detected by ALP assay kit and calcium colorimetric assay kit. Western blot and RT-qPCR were used to determine the expression of osteogenesis-related genes. The interaction between miR-125b and connexin 43 (Cx43) was detected by dual luciferase gene reporter assay. The data were analyzed with SPSS 17.0 software., Results: The cultured PDLSCs showed the characteristics of mesenchymal stem cells. After transfected with miR-125b in PDLSCs, the cell viability was decreased, cytotoxicity was increased; ALP activity, calcium level and the expression of osteogenesis-related genes were significantly decreased. On the contrary, cell viability, ALP activity, calcium level and the expression of osteogenesis-related genes in PDLSCs were increased after anti-miR-125b transfection. Dual luciferase gene reporter assay showed that miR-125b could target Cx43. In addition, the effect of miR-125b on osteogenic differentiation of PDLSCs was reversed after Cx43 overexpression., Conclusions: miR-125b may inhibit osteogenic differentiation of PDLSCs by targeting Cx43.

Purpose: To study the effect of ribosomal S6 kinase (Rsk2) gene on proliferation and osteogenic differentiation of human periodontal ligament cells (hPDLCs) and underlying mechanism., Methods: Premolar surgically extracted were collected, the periodontal ligament was separated and hPDLCs were primarily cultured. Cells of 4 to 6 passage were used in the experiment. The silencing efficiency of small interfering RNA (siRNA) on Rsk2 in hPDLCs was detected by RT-PCR and Western blot. MTT assay was used to detect the effect of Rsk2 siRNA on cell proliferation. Alkaline phosphatase (ALP) kit was used to detect ALP activity. P38MAPK signal pathway inhibitor SB203580 was used to detect hPDLCs after transfection. Western blot was used to detect the effect of Rsk2 siRNA on MAPK signaling pathway p38 protein phosphorylation. The expressions of Runt-related transcription factor-2 (Runx2), osteocalcin (OCN) and osteogenic protein BMP2 were detected by RT-PCR and Western blot. The data were analyzed using SPSS18.0 software package., Results: The expression of Rsk2 was down-regulated by hPDLCs transfected with Rsk2 siRNA, the difference was statistically significant (P<0.05). Rsk2 siRNA significantly reduced phosphorylation of p38 protein (P<0.05), inhibition of hPDLCs proliferation (P<0.05), decreased ALP activity (P<0.01); the expression of Runx2, OCN and BMP2 was different, and the difference was statistically significant (P<0.05). After SB203580 treatment, hPDLCs transfected with Rsk2 siRNA showed increased cell proliferation, ALP activity, Runx2, OCN and BMP2 expression; compared with Rsk2 siRNA transfected hPDLCs, the difference was statistically significant., Conclusions: Rsk2 siRNA inhibits hPDLCs proliferation and osteogenic differentiation through p38MAPK signaling pathway.