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In order to effectively mitigate the oxidation reactions of coal (RC) and gangue (RG) at low temperatures, a comprehensive study was conducted on the mineral composition, structural characteristics, and oxidation behaviors of RC and RG from the same coal seam. Additionally, the thermodynamic attributes of their oxidation processes were evaluated. The results indicate that the mineral composition of RC and RG is similar, primarily comprising kaolinite. However, there are substantial differences in structural characteristics, with RG exhibiting a more stable structure, smaller aromatic layer spacing, and higher degree of graphitization. Additionally, the molecular arrangement is densely packed and orderly, displaying characteristics akin to those of " highly metamorphic coal-like ". RC has a high content of aromatic hydrocarbons and aliphatic hydrocarbons, with long side chains, rendering it more susceptible to oxidation and possessing stronger combustion activity. Upon entry into the oxidation process, RG exhibits a lower initial exothermic temperature due to its strong thermal conductivity and large thermal diffusion coefficient. However, it simultaneously has fewer active functional groups and a higher ash content, limiting its sustained exothermic capacity and prolonging the processes of slow endothermic and rapid exothermic reactions. Conversely, RC, with its high carbon content and abundant active substances, releases heat during oxidation that is 1.7–3.5 times greater than that of RG. Importantly, when RC and RG oxidize together, they exhibit a synergistic effect, promoting the reaction. In the slow endothermic stage, the average activation energy required for CG is 2.64 kJ·mol−1 lower than that for RC. In the rapid exothermic and slow exothermic stages, the actual heat release of CG exceeds the theoretical heat release by 15.95–64.71 J·g−1 and 13.88–56.77 J·g−1, respectively. [ABSTRACT FROM AUTHOR]

The crushing behavior of foamed concrete is utilized to assess the arresting properties of the Engineered Materials Arresting System (EMAS). In this study, polypropylene fibers (PPF) are used to improve the crushing behavior of foamed concrete with and without wet-dry cycles. The results indicate that the compressive strength, initial crushing stress and maximum energy absorption efficiency of foamed concrete with 0.6 % PPF is increased by 71.89 %, 60.85 % and 9.52 %, respectively. After 30 wet-dry cycles, the above three parameters are reduced to 0.21 MPa, 0.71 MPa, and 0.42, respectively, for foamed concrete without fibers, and 0.28 MPa, 0.97 MPa, and 0.44 for foamed concrete with 0.6 % PPF. The analysis based on the tire/foam interface model reveals the potential reduction of the arresting force on the landing gear caused by wet-dry cycles while the fiber reinforcement could partially offset this deterioration. Adding PPF to foamed concrete for EMAS construction has the potential to optimize cement costs and enhance arresting properties. • Crushing behavior of foamed concrete was utilized to assess the arresting properties of EMAS. • Polypropylene fibers (PPF) were used to improve the crushing behavior of foamed concrete with and without wet-dry cycles. • In the range of 0.2–1.0 % PPF fiber content, the best improvement is achieved at 0.6 % fiber content. [ABSTRACT FROM AUTHOR]

Background: Rabies is a fatal zoonotic disease whose pathogenesis has not been fully elucidated, and vaccination is the only effective method for protecting against rabies virus infection. Most inactivated vaccines are produced using Vero cells, which are African green monkey kidney cells, to achieve large-scale production. However, there is a potential carcinogenic risk due to nonhuman DNA contamination. Thus, replacing Vero cells with human diploid cells may be a safer strategy. In this study, we developed a novel 2BS cell-adapted rabies virus strain and analysed its sequence, virulence and immunogenicity to determine its application potential as a human diploid cell inactivated vaccine. Methods and results: The 2BS cell-adapted rabies virus strain 2aG4-B40 was established by passage for 40 generations and selection of plaques in 2BS cells. RNA sequence analysis revealed that mutations in 2BS cell-adapted strains were not located at key sites that regulate the production of neutralizing antibodies or virulence in the aG strain (GQ412744.1). The gradual increase in virulence (remaining above 7.0 logLD50/ml from the 40th to 55th generation) and antigen further indicated that these mutations may increase the affinity of the adapted strains for human diploid cells. Identification tests revealed that the 2BS cell-adapted virus strain was neutralized by anti-rabies serum, with a neutralization index of 19,952. PrEP and PEP vaccination and the NIH test further indicated that the vaccine prepared with the 2aG4-B40 strain had high neutralizing antibody levels (2.24 to 46.67 IU/ml), immunogenicity (protection index 270) and potency (average 11.6 IU/ml). Conclusions: In this study, a 2BS cell-adapted strain of the 2aG4 rabies virus was obtained by passage for 40 generations. The results of sequencing analysis and titre determination of the adapted strain showed that the mutations in the adaptive process are not located at key sequence regions of the virus, and these mutations may enhance the affinity of the adapted strain for human diploid cells. Moreover, vaccines made from the adapted strain 2aG4-B40 had high potency and immunogenicity and could be an ideal candidate rabies virus strain for inactivated vaccine preparation. [ABSTRACT FROM AUTHOR]

• The investigation of surface mid-frequency waviness and machine tool vibration from diverse sources is conducted through micro-planning experiments. The research delves into the influence of cutting conditions on vibration and mid-frequency waviness. • The influence of various components within the cutting force on vibration and mid-frequency waviness in UPM is elucidated through the acquisition, processing, and analysis of cutting force data. • The study discovered a discrepancy in the influence of cutting force on the vibration of stationary and moving components. Cutting force serves as the main excitation source for the vibration of the stationary part, while it exhibits an impedance role in the vibration of the moving part. • The research revealed that the stability and attenuation of the waviness caused by the stationary and moving parts vibration are different spatially and temporally. In addition to the dynamic characteristics of the machine tool, cutting conditions significantly influences the vibration of the cutting system and mid-frequency waviness of the workpiece surface in ultra-precision machining (UPM). In this work, the effects of cutting conditions on machining vibration and surface waviness were investigated by high-speed micro-planning experiments. The origin of vibration and waviness were elucidated by frequency-domain processing of the vibration signal and surface waviness analysis. The dynamic characteristics of machine tool are determined using modal test and analysis. The results revealed that the cutting force has different contributions to the workpiece vibration and tool vibration. In the time domain, distinct differences can be found in stability and attenuation of various waviness components. The divergent effects of cutting force components in different vibration forms are confirmed through a novel cutting force model of micro-planing. The investigation can further reveal the formation mechanisms of cutting system vibration and surface waviness during the micro-cutting process, which can provide practical guidance for suppressing mid-frequency waviness on machined surfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] • Potent and selective HDAC6 inhibitors based on the Tetrahydro- β -carboline scaffold. • Computational simulations suggested the key interactions between representative 11d and HDAC6. • 11d exhibited promising neurite outgrowth-promoting activity and neuroprotective activity. Histone deacetylase 6 (HDAC6) has drawn more and more attention for its potential application in Alzheimer's disease (AD) therapy. A series of tetrahydro- β -carboline (TH β C) hydroxamic acids with aryl linker were synthesized. In enzymatic assay, all compounds exhibited nanomolar IC 50 values. The most promising compound 11d preferentially inhibited HDAC6 (IC 50 , 8.64 nM) with approximately 149-fold selectivity over HDAC1. Molecular simulation revealed that the hydroxamic acid of 11d could bind to the zinc ion by a bidentate chelating manner. In vitro, 11d induced neurite outgrowth of PC12 cells without producing toxic effects and showed obvious neuroprotective activity in a model of H 2 O 2 -induced oxidative stress. [ABSTRACT FROM AUTHOR]

• Self-sensing property of cement-based sensors under flexural load is unsatisfactory. • PVA fibers increase the electrical resistivity of cement-based sensors. • PVA fibers enhance stress–strain sensing of cement-based sensors under flexural load. Cement-based sensors have great potential for structural health monitoring, especially carbon fiber filled functional sensors. In order to improve the sensing efficiency of carbon fiber reinforced cement-based sensors under cyclic flexural loading, polyvinyl alcohol (PVA) fibers were incorporated into cement-based sensors. The PVA fibers, although increasing the electrical resistivity, significantly improved the strain and stress self-sensing properties of carbon fiber reinforced cement-based sensors under cyclic flexural loading. This study provides a new way to accurately measure the parameters of cement-based sensors under cyclic flexural loading. [ABSTRACT FROM AUTHOR]