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Operational parameters of a Tunnel Boring Machine (TBM) under different geological properties have significant influence on muck removal performance. To improve the muck removal performance for Yinsong Tunnel TMB, tuff and granite properties were surveyed by geological detection in the tunnel project, and the optimization of advancement and rotational speed of cutterhead was investigated. The muck model was established by discrete element method (DEM), considering the shape characteristic of muck. The whole muck removal process was simulated, then the influence of the advancement speed and rotational speed on muck removal performance in tuff and granite stratum was studied via numerical simulations. Based on simulation results, the muck removal performance evaluation system of TBM is built using fuzzy mathematics and evaluation theory. Ultimately, optimal operation parameters in the tunnel project is obtained after comprehensive evaluation. The results indicated that the optimum advancement speed should be 7 r/min in both tuff and granite stratum, while the optimal rotational speed was 6 r/min in granite and 5.5 r/min in tuff respectively. Based on TBM engineering application, the size characteristic of muck was obtained from on-site muck specimen analysis and the muck removal performance of TBM under different operation and rock conditions was compared to validate the simulation method. These findings could provide guidance for TBM operation to improve muck removal performance in different geological conditions.

Heavy metal toxicity poses major environmental and health problems. Owing to the high costs of conventional methods to decontaminate soil, sediments and water, there is great scientific and commercial interest in alternate low-cost methods. The use of the plant with special abilities to accumulate contaminants in above-ground biomass to clean up contaminated soil is an efficient and environmental sound method for soil remediation. Lots of field surveys were conducted to find more metal-scavenging plants from the metallophyte species. At the same time, attempts have been made to elucide the physiological and biochemical mechanisms these plants use to accumulative and compartmentalize excess metals, which induces the recent upsurge of interest in exploring the heavy metal localization patterns in these special plant species, Viola principis H. de Boiss （Pubescent Violet） could thrive in soils with polymetallic contamination, and accumulate high concentrations of Pb, Cd and As in its shoot. The heavy metal concentrations in leaves reached Cd 1201 μg ·g^-1, Pb 2350 μg ·g^-1, As 1032 μg ·g^-1. Synchrotron radiation X-ray fluorescence （SRXRF） micro-analysis revealed that higher concentrations of Pb and As were observed in the vascular bundle sheath cells, mesophll, and trichome base compartment. Less of Pb and As was distributed in the xylem than in vascular bundle sheath. The concentrations of Pb in the cuticle of the epidermis were not higher than those in epidermis vacuolar, so did the concentrations of As.

Adipose-derived stem cells (ADSCs) have been demonstrated to improve the microenvironment after a stroke. Increasing studies have confirmed that hypoxia pretreatment of ADSCs resulted in a better therapeutic effect, but the mechanism of treatment is unclear. We isolated ADSCs and exosomes. Then, constructed a middle cerebral artery occlusion (MCAO) mice model. High-throughput sequencing was used to identify the differential expression of circRNA. Immunofluorescence and ELISAs were used to detect the therapeutic effects of ADSC exosomes on MCAO. The luciferase reporter assay was used to detect the interaction relationships among circRNA-Ptpn4, miR-153-3p, and Nrf2. This study showed that exosomes from hypoxia pretreatment of ADSCs had significant effects in promoting functional recovery following in vivo MCAO, through suppressed inflammatory factor expression, and shifting the microglial from M1 to M2 polarization activation. The results showed that circRNA-Ptpn4 was highly expressed during hypoxia pretreatment of ADSCs exosomes. Exosomes from circ-Ptpn4-modified ADSCs had a greater ability to promote functional recovery. The circ-Ptpn4 delivered from ADSC exosomes induced microglia/macrophage polarization from M1 to M2 by suppressing miR-153-3p and enhancing Nrf2 expressions. Taken together, the results showed that exosomes from circRNA-Ptpn4 modified ADSC treatment repaired nerve damage caused by cerebral infarction by inducing microglial M1/M2 polarization.

The antioxidant activity of chitosan (CS) and three water-soluble derivatives was analyzed comparatively by in vitro and in vivo experiments, including hydroxypropyl chitosan (HPCS), quaternary ammonium salt of chitosan (HACC), and carboxymethyl chitosan (CMCS). The results show that chitosan and its water-soluble derivatives have a scavenging ability on DPPH radicals, superoxide radicals, and hydroxyl radicals, and a reducing ability. A remarkable difference (p < 0.05) was found for HACC and HPCS compared with CS on DPPH radicals, hydroxyl radicals, and reducing ability. The antioxidant ability of the four chitosan samples was in the order of HPCS > HACC > CMCS > CS. Furthermore, antioxidant activity of all samples increased gradually in a concentration-dependent manner. The in vivo result indicates that oral CS and its derivatives samples result in a decrease in lipid peroxides (LPO) and free fatty acids (FFA) levels in serum with an increase in superoxide dismutase (SOD) activity. Especially for the HPCS and HACC groups, the LPO, FFA, and SOD activity in serum was different significantly in comparison with the high-fat controlgroup (HF) (p < 0.05). These results indicate that chitosan and its derivatives can be used as good antioxidants, and the antioxidant activity might be related to the molecular structure of chitosan derivatives.

Lycium ruthenicum is an excellent eco-economic shrub. Numerous researches have been conducted for the function of its fruits but scarcely focused on the somaclonal variation and DNA methylation. An efficient micropropagation protocol from leaves and stems of L . ruthenicum was developed in this study, in which not only the leaf explants but also the stem explants of L . ruthenicum were dedifferentiated and produced adventitious buds/multiple shoots on one type of medium. Notably, the efficient indirect organogenesis of stem explants was independent of exogenous auxin, which is contrary to the common conclusion that induction and proliferation of calli is dependent on exogenous auxin. We proposed that sucrose supply might be the crucial regulator of stem callus induction and proliferation of L . ruthenicum . Furthermore, results of methylation-sensitive amplified polymorphism (MSAP) showed that DNA methylation somaclonal variation (MSV) of CNG decreased but that of CG increased after acclimatization. Three types of micropropagated plants (from leaf calli, stem calli and axillary buds) were epigenetically diverged more from each other after acclimatization and the ex vitro micropropagated plants should be selected to determine the fidelity. In summary, plants micropropagated from axillary buds and leaves of L . ruthenicum was more fidelity and might be suitable for preservation and propagation of elite germplasm. Also, leaf explants should be used in transformation. Meanwhile, plants from stem calli showed the highest MSV and might be used in somaclonal variation breeding. Moreover, one MSV hotspot was found based on biological replicates. The study not only provided foundations for molecular breeding, somaclonal variation breeding, preservation and propagation of elite germplasm, but also offered clues for further revealing novel mechanisms of both stem-explant dedifferentiation and MSV of L . ruthenicum .

Oxidative dehydrogenation of propane (ODHP) is a promising route for propylene production, but achieving high selectivity towards propylene while minimizing CO x byproducts remains a significant challenge for conventional metal oxide catalysts. Here we propose a solution to this challenge by employing atomically dispersed dual-atom catalysts (M 1 M' 1 -TiO 2 DACs). Ni 1 Fe 1 -TiO 2 DACs exhibit an ultralow CO x selectivity of 5.2% at a high propane conversion of 46.1% and 520 °C, with stable performance for over 1000 hours. Mechanistic investigations reveal that these catalysts operate via a cooperative Langmuir-Hinshelwood mechanism, distinct from the Mars-van Krevelen mechanism typical of metal oxides. This cooperative pathway facilitates efficient conversion of propane and oxygen into propylene at the dual-atom interface. The superior selectivity arises from facile olefin desorption from the dual-atom sites and suppressed formation of electrophilic oxygen species, which are preferentially adsorbed on Fe 1 sites rather than oxygen vacancies. This work highlights the potential of dual-atom catalysts for highly selective ODHP and provides insights into their unique catalytic mechanism. Propane oxidative dehydrogenation offers a promising path for propylene production, but selective propylene formation with minimal COx remains challenging. Here, the authors introduce dual-atom catalysts achieving just 5.2% COx selectivity at 46.1% propane conversion (520 °C) with stable performance for over 1000 hours.

Background Using microbes and their metabolites as material to develop new biological fungicides is still vital for pesticide development. Our preliminary study found that the endophytic fungi Arthrinium sp. 2–65 of Thymus mongolicus (Ronniger) Ronniger showed a certain inhibitory effect on pathogenic fungi. Results In this study, the antifungal activity of Arthrinium sp. 2–65 was evaluated. The ethyl acetate extract of Arthrinium sp. 2–65 exhibited significant inhibitory activity against pathogenic fungi, especially Botrytis cinerea . The main compounds of Arthrinium sp. 2–65 metabolites were isolated and purified, and the two compounds were identified by infrared spectroscopy (IR), high-performance liquid chromatography (HPLC), 1 H nuclear magnetic resonance (NMR), 13 C NMR, and high-resolution mass spectrometry (HRMS) as 2-hexyl-3-methylmaleic anhydride (A) and 2-carboxymethyl-3- n -hexylmaleic acid anhydride (B). Conclusions The main compounds (A and B) isolated and characterised from the fermentation broth of Arthrinium sp. 2–65 showed satisfactory inhibitory effects against pathogenic fungi, especially B. cinerea . These compounds could be used as potential molecules for the development of novel pesticides to control grey mould.

The purpose of this study was to investigate the clinical efficacy of antibiotic-loaded bone cement (ALBC) combined with Negative pressure wound therapy (NPWT) aspiration technique in the treatment of multidrug-resistant diabetic foot ulcers (MDRO-DFUs). A retrospective analysis of the clinical data of 80 patients with MDROs-DFU who were used Vacuum sealing drainage (VSD) as NPWT excipient and met the inclusion criteria from January 2019 to January 2024 at our hospital. Patients were divided into an experimental group and a control group, with 40 cases in each. The control group received conventional treatment, routine debridement, and NPWT treatment, while the experimental group received ALBC treatment in addition to the treatment plan of the control group. Measurements of blood inflammatory indicators, foot hemodynamic indicators, wound bacterial clearance time, wound healing time, and hospital stay were taken before and after treatment for both groups. Inflammatory indexes, Vascular endothelial growth factor(VEGF), and internal diameter of dorsalis pedis arteriosus of both groups after treatment were significantly better than those before treatment, and the improvement of the experimental group was more obvious than that of the control group; the experimental group had a significantly shorter time of trauma bacterial turnover, healing time of trauma, and hospitalization time compared with that of the control group (P<0.05).

The hydrofluoric acid modified biochar (HF-BC) was obtained, aiming to improve its performance for activating persulfate (PS) to make acid orange 7 (AO7) degraded in water solution. Results showed that the surface area, micropore volume, carboxyl and phenolic hydroxyl group content of HF-BC increased by 171%, 172%, 23.8% and 50%, respectively, compared to unmodified biochar (BC). The decolorization of AO7 in HF-BC/PS and BC/PS systemwas much more rapid and efficient than that in HF-BC, BC and PS alone system. For the HF-BC/PS system, the AO7 was removal of 99.8%, much higher than that of BC/PS system, probably because of its better surface characteristics. Moreover, for the HF-BC/PS system, it was the higher PS concentration and HF-BC dosage that caused greater AO7 degradation rates, and lower pH was favorable for the degradation. Our results provided a novel method to design biochar as an activator for persulfate-based remediation of dye wastewater. Abbreviations: HF-BC, hydrofluoric acid modified biochar; BC, unmodified biochar; AO7, Acid orange 7; PS, persulfate