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Lately, Jiang and Hu (H.B. Jiang, B.Q. Hu, On ( O , G ) -fuzzy rough sets based on overlap and grouping functions over complete lattices, Int. J. Approx. Reason. 144 (2022) 18-50.) put forward ( O , G ) -fuzzy rough sets via overlap and grouping functions over complete lattices. Meanwhile, they showed the characterizations of O -upper and G -lower L -fuzzy rough approximation operators in ( O , G ) -fuzzy rough set model based on some of specific L -fuzzy relations and studied the topological properties of proposed model. Nevertheless, we discover that the partial results given by Jiang and Hu could be further optimized. So, as a replenish of the above article, in this research, based on G -lower L -fuzzy rough approximation operator in ( O , G ) -fuzzy rough set model, we further explore several new conclusions on the relationship between G -lower L -fuzzy rough approximation operator and different L -fuzzy relations. In particular, the equivalent descriptions of relationship between G -lower L -fuzzy rough approximation operator and O -transitive ( O -Euclidean) L -fuzzy relations are investigated, which are not involved in above literature and can make the theoretical results of this newly fuzzy rough set model more perfect.

SUMMARYStrain partitioning between strike-slip faults in mountains and thrust faults in the foreland is a typical mountain building process to accommodate oblique plate convergence. Studying the geometry and movement of such strain-partitioned fault systems is key to understanding the mountain building process and related seismic hazards. The 2022 Mw 6.6 Menyuan earthquake is the largest strike-slip earthquake to have ruptured the northern Qilian Shan fault system in the modern geodetic era. We combined satellite and field observations to determine the fault geometry and coseismic slip distribution in the Menyuan earthquake, and link the distribution of coseismic slip with the pattern of interseismic strain accumulation within the northern Qilian Shan from our geodetic slip model. We find that the Menyuan earthquake ruptured a 25 km-long section of the left-lateral Longlongling Fault between the surface and 7 km depth. The maximum slip was 4 m at 3–4 km depth. Damage to a high-speed railway tunnel recorded a fault offset of 2.7 m at a depth of 200 m compared to 2.5–3.0 m on the surface, suggesting that dispersion of the rupture through unconsolidated shallow sediments was limited, at least at the tunnel site. We also determined the pattern of interseismic deformation prior to the earthquake using Interferometric Synthetic Aperture Radar and Global Navigation Satellite System data. We found the interseismic geodetic data can be explained by the oblique movement of a low-angle décollement beneath the Qilian Shan rather than a strain partitioning fault system. We suggested that the strike-slip faults and foreland thrusts are separated by a creeping décollement, which would act as a barrier to stop the cascading rupture of the strike-slip and thrust fault.

Rough sets, as a powerful tool to deal with uncertainties and inaccuracies in data analysis, have been continuously concerned and studied by many scholars since it was put forward, especially the research on various rough set models. On the other hand, overlap and grouping functions, as two newly aggregation operators and mathematical model to handle the problems involving in information fusion, have been successfully applied in many real-life problems. In this paper, based on overlap and grouping functions, we propose a new fuzzy rough set model named (GO, O)-fuzzy rough sets and consider its characterizations along with topological properties. Properly speaking, firstly, we utilize QL-operators (and also QL-implications) constructed from overlap and grouping functions and fuzzy negations to define the lower approximation operator in (GO, O)-fuzzy rough set model named GO-lower fuzzy rough approximation operator and the upper approximation operator in (GO, O)-fuzzy rough set model is considered as the O-upper fuzzy rough approximation operator in (IO, O)-fuzzy rough set model proposed by Qiao recently. Secondly, we discuss lots of basic properties of (GO, O)-fuzzy rough sets, especially for the properties of GO-lower fuzzy rough approximation operator. Thirdly, we focus on the relationship between (GO, O)-fuzzy rough sets and concrete fuzzy relations. Finally, we give the topological properties of the upper and lower approximation operators in (GO, O)-fuzzy rough set model.

Quantifying surface deformation due to earthquake-related surface rupturing is a critical research focus. Localized offsets on the primary fault can be obtained via field measurements of dislocated landforms. However, effectively quantifying distributed deformation, which can extend for tens to hundreds of meters around the fault zone, has only become possible with the development of remote sensing technology and optical pixel correlation techniques. In this study, we correlated pre- and post-earthquake GaoFen (GF)-2 and -7 images that were ortho-rectified by a digital elevation model generated from GF-7 stereo images to obtain surface horizontal deformation of the 2022 Mw 6.6 Menyuan earthquake. The surface rupture had a total length of 28 km along two segments separated by a stepover; in this study, we focused on the northern segment (23.5 km), which was distributed along the Lenglongling fault (LLLF). The total surface offset measured by our study had the maximum value of 4.0 m and a mean value of 1.9 m. The mean offset measured by field observations captured just 50% of the mean offset from optical pixel correlation. Overall, 57% of off-fault deformation (OFD) occurred on the LLLF, which is a mature fault, owing to soft near-surface materials. Comparison of the surface offset measured by pixel correlation data in our study and near ground slip from joint inversion of Interferometric Synthetic Aperture Radar and pixel correlation data suggests that OFD played a significant role in accommodating the shallow slip. The results of this study offer new insight into the characteristics of surface deformation.

Hydrogen evolution reaction (HER), as an effective method to produce green hydrogen, is greatly impeded by inefficient mass transfer, i.e., bubble adhesion on electrode, bubble dispersion in the vicinity of electrode, and poor dissolved H 2 diffusion, which results in blocked electrocatalytic area and large H 2 concentration overpotential. Here, we report a superaerophilic/superaerophobic (SAL/SAB) cooperative electrode to efficiently promote bubble transfer by asymmetric Laplace pressure and accelerate dissolved H 2 diffusion through reducing diffusion distance. Benefiting from the enhanced mass transfer, the overpotential for the SAL/SAB cooperative electrode at −10 mA cm −2 is only −19 mV, compared to −61 mV on the flat Pt electrode. By optimizing H 2 SO 4 concentration, the SAL/SAB cooperative electrode can achieve ultrahigh current density (−1867 mA cm −2 ) at an overpotential of −500 mV. We can envision that the SAL/SAB cooperative strategy is an effective method to improve HER efficiency and stimulate the understanding of various gas-involved processes.

Funding Information: This work was supported by the Ningbo S&T Innovation 2025 Major Special Program (2020Z059 and 2020Z107), the BoXin project (BX20190339), the Natural Science Foundation of Ningbo (Nos. 2019A610442 and 202003N4351), the China Postdoctoral Science Foundation (Nos. 2019M662127and 2019M662124), and the Hundred Talents Programs in Chinese Academy of Science. The DFT calculation was supported by the High-Performance Computing Center of Collaborative Innovation Center of Advanced Microstructures, Nanjing University. Publisher Copyright: © Fast and stable production of hydrogen peroxide (H2O2) through electrochemical pathways is crucial for wastewater treatment applications. With this objective, herein, we report an integrated and superaerophilic electrode composed of atomically dispersed Ni-O-C site-enriched carbon nanosheets (IS-NiOC electrode) for electrochemical oxygen reduction to produce H2O2. Both experimental and theoretical results have proven that atomically dispersed Ni-O-C sites enable a low overpotential (260 mV at 0.1 mA cm-2) and high selectivity (>90% at 0.0-0.5 V vs reversible hydrogen electrode (RHE)) in a neutral electrolyte. Compared with a commercial gas-diffusion electrode, the IS-NiOC electrode offers stronger affinity to oxygen bubbles and more robust three-phase contact points, resulting in high current density (∼106 mA cm-2 at 0.25 V vs RHE) and superior stability (∼200 h). These merits allow the application of the IS-NiOC electrode in an electro-Fenton-like process, which enables fast degradation of representative organic pollutants in both a steady state and a flow state.

In the field of cultural relic protection, the migration of moisture will cause a series of adverse effects, such as disruption and crater eruption. Assessment of water migration status is the key to early warning and prevention of these problems. In an attempt for a solution, the whole process of moisture migration in rammed earth is studied by using the moisture migration initiation criterion based on entropy. We analyzed and compared the entropy change law of the infrared radiation temperature in the two main migration stages, and we made a judgment on whether the moisture state is in the steady equilibrium or in the process of dynamic migration. The results show that the moisture migration status can be identified quickly and in real time by using the moisture migration initiation criterion based on entropy. The results of this study provide a new method for judging the state of moisture migration in geotechnical engineering, especially in the field of cultural relic protection, which has very important practical significance.

Review question / Objective: According to the current randomized clinical trials (RCT) of acupuncture therapy for Alzheimer's disease (AD), to evaluate their methodology, the quality of evidence and the report are evaluated and summarize evidence of important outcomes of randomized clinical trials. We aim to provide accurate clinical decision-making for acupuncture treatment of Alzheimer's disease. Condition being studied: According to the current randomized clinical trials (RCT) of acupuncture therapy for Alzheimer's disease (AD), to evaluate their methodology, the quality of evidence and the report are evaluated and summarize evidence of important outcomes of randomized clinical trials. We aim to provide accurate clinical decision-making for acupuncture treatment of Alzheimer's disease.

SUMMARY: The aim of the present study was to evaluate the changes of alveolar bone in aged rats. The mandibles of the 4- month and 22-month aged rats were scanned by micro-CT. After the reconstruction of the alveolar bone,the distance between the cemento enamel junction (CEJ) and the alveolar bone crest (ABC) was measured. The micro architectures of the inter-radicular alveolar bone were analyzed. The 22-month rats experienced the reduction in alveolar crest height in the buccal side and the lingual side, and significant increase in alveolar bone loss compared with the 4-month rats. The 22-month rats had a porous microarchitecture, the trabecular arrangement was obviously dissociated with the expanded inter-bone spaces of marrow, and the bone histomorphometry analysis showed the decreased bone volume/tissue volume and trabecular thickness in the 22-month rats. These results suggest that alveolar bone loss and alveolar trabecular bone deterioration might contribute to the weakening of molar support in the elderly.

As a key risk source for tunnel engineering, the entrance section of tunnel is extremely easy to collapse. By analyzing the collapse of the entrance section of Taojiakuang Tunnel, the deformation characteristics before the tunnel collapsed were obtained. From the aspects of construction method and advanced support, three kinds of working conditions were considered to optimize the original design. From the perspective of safety and economy, the original advanced support design is unreasonable, and the conversion of the center cross diagram method to the center diagram method is not appropriate. For construction of tunnel entrances in weak broken rock, it is necessary to use the appropriate excavation method. When changing construction method, it is necessary to carry out sufficient demonstration and then re-construction to prevent the initial deformation of the surrounding rock from being too large and causing the tunnel to collapse. When encountering a weak broken zone, especially a rock formation boundary, it is necessary to increase the length of the advance support. The study provides a technical reference for similar projects.

A study of understanding the effect of morphology during the electrochemical CO2 reduction on bismuth catalysts is presented. Three types of pristine bismuth catalysts with designed morphologies were synthesized via the hydrothermal method and their catalytic activity and selectivity towards electrochemical CO2 reduction were analyzed and discussed. In comparison with bismuth nanowires and nanospheres, two-dimensional bismuth nanosheets with a thickness of 10 nm show enhanced selectivity for formate formation due to the highest (012) facet texture coefficient value. The highest Faradaic efficiency of 85% for the formation of formate was achieved at −0.85 V vs. RHE and a stability electrolysis test conducted at the same potential showed only 8% activity loss over 8 h. These results reveal the importance of the nanoengineering strategy for developing the next generation of non-precious metal electrocatalyst for CO2 reduction.

In this work, we present a supramolecular template-derived synthesis approach combined with a carbon electronic structure tailoring strategy to prepare N-doped carbon (NC) nanosheets with delicately tuned nitrogen dopant levels and types for selective CO2 electrocatalytic reduction. By this method, the NC nanosheets are able to electrochemically reduce CO2 to CO with an unprecedentedly superior Faradaic efficiency (FE) of 92% at a moderate overpotential as low as −0.36 V and showed great long-term stability with a remnant FECO around 85% after 10 h of electrolysis. The improved performance of NC nanosheets is mainly attributed to the synergetic effect of the electronic interaction of pyridinic nitrogen with adjacent C atoms in the interfacial nanoregime and the concomitant pore structure, high conductivity, as well as surface wettability. The capability to modulate the catalytic site electron densities opens up further opportunities for the rational re-engineering of carbon-based catalysts with accelerate...

The lithium–sulfur (Li–S) battery is considered as a promising battery chemistry for next-generation energy storage on the merits of low cost and high energy density. However, the sluggish redox ki...

Solar-powered desalination is a promising way to resolve the worldwide water crisis for its low consumption and simple facility. Considering the fragility and aggregations of traditional materials, which may decrease efficiency, we herein introduce a robust tungsten carbide (WC) nanoarray film as a stable and efficient photothermal material, whose absorption is over 97.5% throughout almost the whole solar spectrum range (220-2200 nm) due to nanoarray structure and thus enhanced localized surface plasmon resonance. Besides, for the first time, we modified the film with sandwich wettability. It accelerates evaporation by reducing waters reflection of light, enlarging hydrophobic-hydrophilic boundaries, and depressing heat dissipation. Combining high absorption with unique wettability, the WC nanoarray film offers high solar-to-vapor efficiency of 90.8% and produces drinking water at the rate of (1.06 ± 0.10) kg m−2 h−1 from man-made seawater and (0.98 ± 0.18) kg m−2 h−1 from heavy metal sewage under one sun (AM 1.5) while 98% performance remains after 1 h × 100 times reutilization.

Fast and stable production of hydrogen peroxide (H2O2) through electrochemical pathways is crucial for wastewater treatment applications. With this objective, herein we report an integrated and superaerophilic electrode composed of atomically dispersed Ni-O-C sites enriched carbon nanosheets (IS-NiOC electrode) for electrochemical oxygen reduction to produce H2O2. Both experimental and theoretical results have proven that atomically dispersed Ni-O-C sites enable a low overpotential (260 mV at 0.1 mA cm− 2) and high selectivity (> 90% at 0.0 ~ 0.5 V vs. RHE) in neutral electrolyte. Compared with a commercial gas-diffusion electrode, the IS-NiOC electrode offers stronger affinity to oxygen bubbles and more robust three-phase contact points, resulting in high current density (~ 106 mA cm− 2 at 0.25 V vs. RHE) and superior stability (~ 200 h). These merits allow the application of the IS-NiOC electrode in an electro-Fenton-like process, which enables fast degradation of representative organic pollutants in both steady state and flow state.

Funding Information: This work was supported by the Academy of Finland (the Profi 5 project). This work made use of the Aalto University RawMaterials (Aalto-RAMI) and Nanomicroscopy Center (Aalto-NMC) infrastructures. Mr. Lijun Fan acknowledges the financial support from the China Scholarship Council (No. 201806250102). The authors would like to thank Dr. Hongjiao Li for fruitful discussions. Funding Information: This work was supported by the Academy of Finland (the Profi 5 project). This work made use of the Aalto University RawMaterials (Aalto‐RAMI) and Nanomicroscopy Center (Aalto‐NMC) infrastructures. Mr. Lijun Fan acknowledges the financial support from the China Scholarship Council (No. 201806250102 ). The authors would like to thank Dr. Hongjiao Li for fruitful discussions. Publisher Copyright: © 2021 The Authors Developing highly efficient and robust electrocatalysts for oxygen evolution reaction (OER) is critical to renewable energy technologies. Here, we report an effective strategy to enhance the OER activity of a perovskite electrocatalyst through improving the electrical conductivity introduced by the structural transition. La0.7Sr0.3Fe1−xNixO3−δ (denoted as LSFN-x) with increasing Ni content is found to crystallize in a higher symmetry structure and exhibit improved OER catalytic performance. The optimized cubic LSFN-0.4 catalyst delivers a 90–times higher specific activity than its non-doped parent rhombohedral compound La0.7Sr0.3FeO3−δ at an overpotential of 340 mV, with an overpotential of only 320 mV for 10 mA cm−2 and a low Tafel slope of 35 mV dec−1 in 0.1 M KOH, while maintaining excellent durability during 1000 continuous cycles and 50 h-water-splitting in a laboratory-scale electrolyzer. The enhanced OER catalytic performance of LSFN-0.4 is highly correlated with its increased conductivity as well as the increased oxygen vacancy concentration.

Background: In the field of antibacterial, nanomaterials are favored by researchers because of their unique advantages. Medicinal plants, especially traditional Chinese medicine, are considered to be an important source of new chemicals with potential therapeutic effects, as well as an important source for the discovery of new antibiotics. MRSA is endangering people's lives as a kind of multidrug-resistant Staphylococcus aureus, which is resistant to tetracycline, amoxicillin, norfloxacin and other first-line antibiotics. It is a hotspot to find good anti-drug-resistant bacteriae, nature-originated nanomaterials with good biocompatibility. Objective: We reported the formation of phytochemical nanoparticles (NPs) by the self-assembly of berberine (BBR) and 3,4,5-methoxycinnamic acid (3,4,5-TCA) from Chinese herb medicine, which had good antibacterial activity against MRSA. Method and Results: We found that NPs had good antibacterial activity against MRSA; especially, its antibacterial activity was better than first-line amoxicillin, norfloxacin and its self-assembling precursors on MRSA. When the concentration reached 0.1 μmol/mL, the inhibition rate of NPs reached 94.62%, which was higher than that of BBR and the other two antibiotics (p < 0.001). It was observed by Field-Emission Scanning Electron Microscopy (FESEM) that NPs could directly adhere to the bacterial surface, which might be an important aspect of the antibacterial activity of NPs. Meanwhile, we further analyzed that the self-assembly was formed by hydrogen bonds and π-π stacking through Ultraviolet-Visible (UV-vis), Fourier Transform Infrared Spectroscopy (FTIR), hydrogen Nuclear Magnetic Spectrum (1H NMR), and powder X-ray Diffraction (pXRD). NPs’ morphology was observed by FESEM and TEM. The particle size and surface charge were characterized by Dynamic Light Scattering (DLS); and the surface charge was -31.6 mv, which proved that the synthesized NPs were stable. Conclusion: We successfully constructed a naturally self-assembled nanoparticle, originating from traditional Chinese medicine, which had a good antibacterial activity for MRSA. It is a promising way to obtain natural nanoparticles from medicinal plants and apply them to antibacterial therapy.

Oxygen reduction efficiency holds the key for renewable energy technologies including fuel cells and metal-air batteries, which involves coupling diffusion-reaction-conduction processes at the interface of catalyst/electrolyte, and thus rational electrode design facilitating mass transportation stands as a key issue for fast oxygen reduction reaction (ORR). Herein, we report a Janus electrode with asymmetric wettability prepared by partly modifying aerophobic nitrogen doped carbon nanotube arrays with polytetrafluoroethylene (PTFE) as a high performance catalytic electrode for ORR. The Janus electrode with opposite wettability on adjacent sides maintains stable gas reservoir in the aerophilic side while shortening O2 pathway to catalysts in the aerophobic side, resulting in superior ORR performance (22.5 mA/cm2 @ 0.5 V) than merely aerophilic or aerophilic electrodes. The Janus electrode endows catalytic performance even comparable to commercial Pt/C in the alkaline electrolyte, exploiting a previously unrecognized opportunity that guides electrode design for the gas-consumption electrocatalysis.

The rational structure and composition manipulation for the efficient, affordable bifunctional electrocatalysts of the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR) is critical for renewable-energy technologies including fuel cells and metal–air batteries. Metal oxide nanoarray electrodes are considered to be alternative options for this issue, although they always suffer from poor conductivity and limited ORR performance in terms of onset potential and diffusion current. In this study, we develop an alternative strategy to prepare a novel bifunctional catalyst by coating three-dimensional CoOx nanoarrays with a porous nitrogen-doped carbon layer (NC). The porous NC not only provides a conductive coating to benefit the charge transfer and retains the channels for electrolyte diffusion, but also greatly enhances the electrochemical surface area, which endows the electrode with higher activity for both the OER and ORR in terms of onset potential and diffusion current. When employed as an air cathode in rechargeable zinc–air batteries over 100 cycles, the electrode exhibits durable performance superior to those of Pt/C and IrO2/C. The results fully demonstrate the great potential of the strategy in electrode construction.

A high temperature protective coating was prepared onto the surface of 20CrMnTi steel by brushing technique, and the heated billet was subjected to hot forging. Compared with an uncoated sample, the effect of coating on high-temperature oxidation behavior of steel was investigated by scanning electron microscopy-energy dispersive spectroscopy and X-ray diffraction. Before hot forging, an oxide layer of 153 μm was formed on the surface of the uncoated sample; however, no oxide layer was formed on the surface of the coated sample. After hot forging, the thickness of scale on the surface of uncoated gear forging is 89 μm while the thickness of coating on the surface of coated gear forging is 39 μm. It is concluded that such a coating material not only enhances the dimensional accuracy but also improves the surface quality of the gear.

Betulinic acid (BA) is a star member of the pentacyclic triterpenoid family, which exhibits great prospects for antitumor drug development. In an attempt to develop novel antitumor candidates, 21 BA-nitrogen heterocyclic derivatives were synthetized, in addition to four intermediates, 23 of which were first reported. Moreover, they were screened for in-vitro cytotoxicity against four tumor cell lines (Hela, HepG-2, BGC-823 and SK-SY5Y) by a standard methylthiazol tetrazolium (MTT) assay. The majority of these derivatives showed much stronger cytotoxic activity than BA. Remarkably, the most potent compound 7e (the half maximal inhibitory concentration (IC50) of which was 2.05 ± 0.66 μM) was 12-fold more toxic in vitro than BA-treated Hela. Furthermore, multiple fluorescent staining techniques and flow cytometry collectively revealed that compound 7e could induce the early apoptosis of Hela cells. Structure–activity relationships were also briefly discussed. The present study highlighted the importance of introducing nitrogen heterocyclic rings into betulinic acid in the discovery and development of novel antitumor agents.

The fabrication of cost effective and efficient electrocatalysts with functional building blocks to replace noble metal ones is of great importance for energy related applications yet remains a great challenge. Herein, we report the fabrication of a hierarchical structure containing CNTs/graphene/transition-metal hybrids (h-NCNTs/Gr/TM) with excellent bifunctional oxygen electrocatalytic activity. The synthesis was rationally designed by the growth of shorter nitrogen-doped CNTs (S-NCNTs) on longer NCNTs arrays (L-NCNTs), while graphene layers were in situ generated at their interconnecting sites. The hybrid material shows excellent OER and ORR performance, and was also demonstrated to be a highly active bifunctional catalyst for Zn–air batteries, which could be due to rapid electron transport and full exposure of active sites in the hierarchical structure.

Tungsten carbide is one of the most promising electrocatalysts for the hydrogen evolution reaction, although it exhibits sluggish kinetics due to a strong tungsten-hydrogen bond. In addition, tungsten carbide’s catalytic activity toward the oxygen evolution reaction has yet to be reported. Here, we introduce a superaerophobic nitrogen-doped tungsten carbide nanoarray electrode exhibiting high stability and activity toward hydrogen evolution reaction as well as driving oxygen evolution efficiently in acid. Nitrogen-doping and nanoarray structure accelerate hydrogen gas release from the electrode, realizing a current density of −200 mA cm−2 at the potential of −190 mV vs. reversible hydrogen electrode, which manifest one of the best non-noble metal catalysts for hydrogen evolution reaction. Under acidic conditions (0.5 M sulfuric acid), water splitting catalyzed by nitrogen-doped tungsten carbide nanoarray starts from about 1.4 V, and outperforms most other water splitting catalysts., Water electrolysis can generate carbon-neutral hydrogen gas from water, yet the required catalysts are often expensive, scarce, and poor at gas release. Here, the authors prepared nitrogen-doped carbon tungstide nanoarrays with high water-splitting activities and bubble-releasing surfaces.

This study investigated the removal of sulfonated humic acid (SHA) from water through a hybrid electrocoagulation–ultrafiltration treatment process. The effects of major operating parameters including electrocoagulation time, current density, and initial pH on the electrocoagulation performance were evaluated. The increase in current density and operating time as well as decrease of pH improved the SHA removal efficiency. The operating conditions of electrocoagulation process were optimized through Box–Behnken design to maximize SHA removal. The optimum conditions for electrocoagulation included time of 7 min, current density of 10 mA/cm2, and pH of 5. Effective SHA removal was further achieved in the hybrid electrocoagulation–ultrafiltration treatment process. The performances of three molecular weight cutoff membranes were examined. The results showed that the SHA removal efficiency increased with the increasing initial concentration of SHA and decreased with the increasing transmembrane pressure. The S...

The osteogenic capacities of bone marrow-derived stromal cells (BMSCs) diminish during replicative senescence, and these changes affect the success of therapeutic application of BMSCs. In this study, we sought to explore the molecular mechanisms underlying the osteogenic differentiation capacities that occur during replicative senescence. It is well known that Oct4 is a key transcription factor essential for maintaining differentiation capacities of the stem cells. In this study, we found that BMSCs at passage 6 (replicative senescent BMSCs) showed marked decreases in the osteogenic differentiation potential and the level of Oct4. These were accompanied by reduced levels of Snf5 and histone H3 lysine-4 trimethylation (H3K4me3) in the Oct4 promoter. In BMSCs at passage 2, knockdown of Snf5 diminished expression of Oct4 and disrupted the up-regulation of alkaline phosphatase (ALP) and runt-related transcription factor 2 (Runx2) after osteogenic differentiation induction, which was accompanied by a reduction in Snf5 and H3K4me3 binding to the Oct4 promoter. These findings indicate that the decreased level of Snf5 binding to the promoter region of the Oct4 gene down-regulated the expression of Oct4, which may be the mechanism underlying the decline in osteogenic capacities in replicative senescent BMSCs.