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Abstract Moisture content of rock/coal can change its mechanical properties and absorption capacities, which can directly affect gas diffusivity, change the stress distribution and hence cause significant impacts on the overall gas or coal extraction process. Observation of the water penetration process and water distribution in the coal matrix will be beneficial for the understanding of the fluid-solid coupling mechanism in hydraulic fracturing, aquifer cracking and coal seam infusion. However, the observation of water penetration process and the determination of water distribution mode were hard to be non-destructively achieved as coal is a non-uniform, inhomogeneous and un-transparent material. µ-CT imaging, which is based on variation of X-ray attenuation related to the density and atomic composition of the scanned objects, enables a four-dimensional (spatial-temporal) visualise of the heterogeneous and anisotropic coal samples. The primary aim of this paper is extending the application of µ-CT imaging to explore the moisture penetration and distribution within coal samples during water infusion process, which has been reported by very little literature. The working principle and procedures of CT imaging was firstly introduced. Then, the determination equation of moisture distribution based on density profile was established. The CT determined moisture content has been compared with weighting method for verification. The paper has demonstrated that µ-CT can be used for non-destructively imaging the moisture distribution within coal samples.

IntroductionThe genus Sanicula L. is a taxonomically complicated taxa within Apiaceae, as its high variability in morphology. Although taxonomists have performed several taxonomic revisions for this genus, the interspecific relationships and species boundaries have not been satisfactorily resolved, especially for those endemic to China. This study mainly focused on S. giraldii var. ovicalycina, S. tienmuensis var. pauciflora, and S. orthacantha var. stolonifera and also described two new members of the genus.MethodsWe newly sequenced sixteen plastomes from nine Sanicula species. Combined with eleven plastomes previously reported by us and one plastome downloaded, we performed a comprehensively plastid phylogenomics analysis of 21 Sanicula taxa. Results and DiscussionThe comparative results showed that 21 Sanicula plastomes in their structure and features were highly conserved and further justified that two new species were indeed members of Sanicula. Nevertheless, eleven mutation hotspot regions were still identified. Phylogenetic analyses based on plastome data and the ITS sequences strongly supported that these three varieties were clearly distant from three type varieties. The results implied that these three varieties should be considered as three independent species, which were further justified by their multiple morphological characters. Therefore, revising these three varieties into three independent species was reasonable and convincing. Moreover, we also identified and described two new Sanicula species (S. hanyuanensis and S. langaoensis) from Sichuan and Shanxi, China, respectively. Based on their distinct morphological characteristics and molecular phylogenetic analysis, two new species were included in Sanicula. In summary, our study impelled the revisions of Sanicula members and improved the taxonomic system of the genus.

Coal rock dynamic disasters such as rockburst and gas outbursts pose severe threats to the safe and efficient mining of coal mines in China; however, the mechanical mechanisms of those disasters are still unknown. Therefore, the evolution law and constitutive model of damage and fracture of coal rock was emphatically studied, starting from the rockburst-gas disaster that occurred at the coal mine roadway. Firstly, the X-ray high-precision micro-CT scanning experiment was performed, and the high-resolution 3D digital core of burst-prone coal was built utilizing 3D reconstruction technology. Furthermore, the box-counting dimension method and the 3D visual image processing software AVIZO were used to calculate the characteristic parameters of mineral bands and crack structures inside the coal sample. Secondly, a damage-fracture constitutive model considering three-parameter Weibull distribution, gas influence, and effective stress was proposed, based on CT scanning reconstruction and statistical strength theory. Thirdly, the triaxial compression experiments of gas-bearing coal were conducted, the model parameters were calculated using experimental results, the model was verified, and the damage evolution law of the progressive failure process of coal rock was revealed. Specifically, the experimental results of micro-CT scanning reconstruction and fractal calculation show that the surface area ratio and fractal dimension of the mineral bands are 0.0035−0.0137 and 1.1214−1.2342 respectively, while that of the fracture structures are 0.0006−0.0040 and 1.0651−1.1454 respectively. The surface area ratio and fractal dimension of mineral bands are generally larger than those of fracture structures, indicating that the number of discontinuous structures of burst-prone coal is significant, and its distribution is complex. Furthermore, the experimental results show that stress-strain curves are characterized by the class I curve; shear fracture usually occurs under triaxial compressive loads. The peak strength and peak strain increase with the rise in confining pressure. Moreover, the determination method of seven parameters within the damage fracture model is given, and those parameters and damage variable are solved based on experimental results. The calculation results show that this model can accurately reflect the progressive failure characteristics of coal rock, such as compressive deformation, quasi-linear elastic deformation, plastic deformation, peak strength, and post-peak softening. Additionally, in the first two stages, the damage variable of coal rock is less than 0.2. When it enters the plastic stage, especially in the post-peak step, the damage variable increases sharply until the failure occurs. Hence, the concept of damage threshold is proposed; here, the damage threshold of 0.2 is recommended as the early warning value of damage fracture of coal rock. The findings will further promote the development of damage mechanics and provide a theoretical basis for the prevention and control of coal and rock dynamic disasters.

BackgroundIruplinalkib is a second-generation anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI) with efficacy in patients with ALK-positive crizotinib-resistant advanced non-small cell lung cancer (NSCLC), which is independently developed by a Chinese pharmaceutical company. This study examined the cost-effectiveness of iruplinalkib versus alectinib in the Chinese healthcare setting.MethodsA partitioned survival model was developed to project the economic and health outcomes. Efficacy was derived using unanchored matching-adjusted indirect comparison (MAIC). Cost and utility values were obtained from the literature and experts’ opinions. Deterministic and probabilistic sensitivity analyses (PSA) were carried out to evaluate the model’s robustness.ResultsTreatment with iruplinalkib versus alectinib resulted in a gain of 0.843 quality-adjusted life years (QALYs) with incremental costs of $20,493.27, resulting in an incremental cost-effectiveness ratio (ICER) of $24,313.95/QALY. Parameters related to relative efficacy and drug costs were the main drivers of the model outcomes. From the PSA, iruplinalkib had a 90% probability of being cost-effective at a willingness-to-pay threshold of $37,863.56/QALY.ConclusionCompared to alectinib, iruplinalkib is a cost-effective therapy for patients with ALK-positive crizotinib-resistant advanced NSCLC.

Abstract The gas content is crucial for evaluating coal and gas outburst potential in underground coal mining. This study focuses on investigating the in-situ coal seam gas content and gas sorption capacity in a representative coal seam with multiple sections (A1, A2, and A3) in the Sydney basin, where the CO2 composition exceeds 90%. The fast direct desorption method and associated devices were described in detail and employed to measure the in-situ gas components (Q 1, Q 2, and Q 3) of the coal seam. The results show that in-situ total gas content (Q T) ranges from 9.48 m3/t for the A2 section to 14.80 m3/t for the A3 section, surpassing the Level 2 outburst threshold limit value, thereby necessitating gas drainage measures. Among the gas components, Q 2 demonstrates the highest contribution to Q T, ranging between 55% and 70%. Furthermore, high-pressure isothermal gas sorption experiments were conducted on coal samples from each seam section to explore their gas sorption capacity. The Langmuir model accurately characterizes CO2 sorption behavior, with fit coefficients (R 2) greater than 0.99. Strong positive correlations are observed between in-situ gas content and Langmuir volume, as well as between residual gas content (Q 3) and sorption hysteresis. Notably, the A3 seam section is proved to have a higher outburst propensity due to its higher Q 1 and Q 2 gas contents, lower sorption hysteresis, and reduced coal toughness f value. The insights derived from the study can contribute to the development of effective gas management strategies and enhance the safety and efficiency of coal mining operations.

Soluble sugars, as an indispensable source of energy, play crucial roles in plant growth and development. However, to date, scant information about the sucrose metabolism-related gene families is available in kiwifruit (Actinidia rufa Planch). Here, we systematically identified the members of various gene families encoding crucial enzymes or transporters involved in sucrose metabolism, re-analyzed their expression patterns under different fruit development stages, and determined the regulatory mechanism involving key transcription factors. A total of sixty-two genes from six gene families (thirty-one ArINVs, two ArSPPs, four ArSPSs, nine ArSUSs, six ArSUCs/SUTs, and ten ArSWEETs) were identified in the A. rufa genome. The characterization of these members, including gene structure, motifs, conserved domains, and cis-acting elements, were analyzed. Phylogenetic analysis revealed that these gene families could be categorized into six distinct subgroups. These six gene families have undergone strong purifying selection during domestication. In addition, expression analysis of the 62 genes indicated that differential expression patterns are highly regulated by developmental processes. Specifically, we identified 11 transcription factors that were rigorously correlated (r > 0.98) with key gene expression profiles. This represents a comprehensive analysis of the genes involved in sucrose metabolism in kiwifruit, which provides useful information for further functional analysis of these genes.

Twenty-seven specimens were tested to investigate the uniaxial compression behaviour of an innovative standing support for underground space applications. The innovative standing support consisted of an external fibre reinforced polymer (FRP) jacket and the infill column made of cementitious grout, tailings and coal wash rejects. Effects of the FRP layers number and water to the cementitious grout (w/g) ratio were evaluated. Test results indicated that lower w/g ratios produced stronger infill columns. With FRP confinement, the standing support demonstrated strain-hardening loading characteristics with a significant improvement in both strength and ductility. The highest strength and strain of the specimens achieved was 58.4 MPa and 11.8% respectively. Compared with the unconfined specimens, the confinement with four FRP layers increased the specimen strength and associated strain up to 3.6 and 27.0 times respectively. A correlation between the compressive strength of the infill material and the ultrasonic pulse velocity was also investigated. Furthermore, a simple design-oriented model was proposed to predict the peak strength and the corresponding strain of the innovative standing support.

Abstract Carmustine (BCNU), a vital type of chloroethylnitrosourea (CENU), inhibits tumor cells growth by inducing DNA damage at O 6 position of guanine and eventually forming dG-dC interstrand cross-links (ICLs). However, the clinical application of BCNU is hindered to some extent by the absence of tumor selectivity, poor stability and O 6-alkylguanine-DNA alkyltransferase (AGT) mediated drug resistance. In recent years, tumor microenvironment has been widely utilized for advanced drug delivery. In the light of the features of tumor microenvironment, we constructed a multifunctional hypoxia/esterase-degradable nanomicelle with AGT inhibitory activity named HACB NPs for tumor-targeting BCNU delivery and tumor sensitization. HACB NPs was self-assembled from hyaluronic acid azobenzene AGT inhibitor conjugates, in which O 6-BG analog acted as an AGT inhibitor, azobenzene acted as a hypoxia-responsive linker and carboxylate ester bond acted as both an esterase-sensitive switch and a connector with hyaluronic acid (HA). The obtained HACB NPs possessed good stability, favorable biosafety and hypoxia/esterase-responsive drug-releasing ability. BCNU-loaded HACB/BCNU NPs exhibited superior cytotoxicity and apoptosis-inducing ability toward the human uterine cervix carcinoma HeLa cells compared with traditional combined medication of BCNU plus O 6-BG. In vivo studies further demonstrated that after a selective accumulation in the tumor site, the micelles could respond to hypoxic tumor tissue for rapid drug release to an effective therapeutic dosage. Thus, this multifunctional stimulus-responsive nanocarrier could be a new promising strategy to enhance the anticancer efficacy and reduce the side effects of BCNU and other CENUs.

Abstract Recent reports suggest that salidroside protects cardiomyocytes from oxidative injury and stimulates glucose uptake by skeletal muscle cells. Despite these findings, the therapeutic potential of salidroside in the treatment of obesity and insulin resistance remains uncertain and requires further investigation. In the present study, the treatment effect of salidroside on the onset and development of the obese phenotype and insulin resistance as well as the underlying mechanisms was investigated using long‐term high‐fat diet‐induced obese mice supplemented with salidroside. We used biochemical kits to determine serum biochemical parameters (including triacylglycerol, total cholesterol, high‐density lipoprotein cholesterol, low‐density lipoprotein cholesterol, fasting glucose, and insulin). The results show that salidroside‐supplemented animals showed better glucose tolerance and insulin sensitivity, decreased blood lipids, and weight gain (p

The genus Rorippa belongs to the family Brassicaceae, and its members usually have high medicinal value. The genus consists of approximately 75 species and mainly grows in the Northern Hemisphere, occurring in every continent except Antarctica. The taxonomy and phylogenetic relationships of Rorippa are still unsettled, largely due to complex morphological variations in Rorippa, which were caused by frequent hybridization events. Here, we sequenced four complete plastid genomes of Rorippa species by Illumina paired-end sequencing. The four new plastid genomes of Rorippa ranged in total size from 154,671 bp for R. palustris to 154,894 bp for R. sylvestris. There are 130 genes in the four plastomes, embodying 8 rRNA, 37 tRNA, and 85 protein-coding genes. Combining with six published plastid genomes, we carried on comparative and phylogenetic analyses. We found that the ten Rorippa plastid genomes were conservative in gene number and order, total size, genomic structure, codon usage, long repeat sequence, and SSR. Fourteen mutational hotspot regions could be selected as candidate DNA barcoding to distinguish Rorippa plants. The phylogenetic trees clearly identified that ten Rorippa species displayed monophyletic relationships within the tribe Cardamineae based on plastomes and nrDNA ITS sequences. However, there are significant cytonuclear discordances in the interspecific relationships within Rorippa, as well as the intergeneric relationships between Rorippa and its related genera. We inferred that the cytonuclear discordance is most likely a result of interspecific hybridization within Rorippa, as well as intergeneric hybridization with its related genera. These plastid genomes can offer precious information for studies of species authentication, evolutionary history, and the phylogeny of Rorippa.

Colorectal carcinoma (CRC) is a major global health concern, with cancer metastasis being the main cause of patient mortality, and current CRC treatments are challenged by drug resistance. Although natural compounds, especially in foods like hawthorn proanthocyanidin extract (HPOE), have good anticancer activity, their effects on CRC metastasis remain unknown. Therefore, our objective was to investigate the impact and potential mechanisms of HPOE on the movement and infiltration of cells in the HCT116 CRC cells. Firstly, scratch-healing experiments confirmed the anti-migratory and anti-invasive capabilities of HPOE. Then, network pharmacology identified 16 possible targets, including MMP-9. Subsequently, RT-qPCR and Western blotting experiments confirmed that HPOE downregulated epithelial-mesenchymal transition-related factors (N-cadherin and MMP-9) and inhibited Wnt/β-catenin pathway activation. Finally, these results were experimentally validated using the Wnt pathway activator Licl and inhibitor XAV939. It was confirmed that HPOE had a certain inhibitory effect on the activation of the Wnt signaling pathway caused by the activator Licl and could enhance the inhibitory effect of the inhibitor XAV939. Our findings provide a basis for developing functional foods or dietary supplements, especially positioning HPOE as a functional food raw material for adjuvant treatment of CRC, given its ability to inhibit metastasis through the Wnt/β-catenin pathway.

Well-developed pores and cracks in coal reservoirs are the main venues for gas storage and migration. To investigate the multi-scale pore fractal characteristics, six coal samples of different rankings were studied using high-pressure mercury injection (HPMI), low-pressure nitrogen adsorption (LPGA-N2), and scanning electron microscopy (SEM) test methods. Based on the Frankel, Halsey and Hill (FHH) fractal theory, the Menger sponge model, Pores and Cracks Analysis System (PCAS), pore volume complexity (Dv), coal surface irregularity (Ds) and pore distribution heterogeneity (Dp) were studied and evaluated, respectively. The effect of three fractal dimensions on the gas adsorption ability was also analyzed with high-pressure isothermal gas adsorption experiments. Results show that pore structures within these coal samples have obvious fractal characteristics. A noticeable segmentation effect appears in the Dv1 and Dv2 fitting process, with the boundary size ranging from 36.00 to 182.95 nm, which helps differentiate diffusion pores and seepage fractures. The D values show an asymmetric U-shaped trend as the coal metamorphism increases, demonstrating that coalification greatly affects the pore fractal dimensions. The three fractal dimensions can characterize the difference in coal microstructure and reflect their influence on gas adsorption ability. Langmuir volume (VL) has an evident and positive correlation with Ds values, whereas Langmuir pressure (PL) is mainly affected by the combined action of Dv and Dp. This study will provide valuable knowledge for the appraisal of coal seam gas reservoirs of differently ranked coals.

Glioma is extremely difficult to be completely excised by surgery due to its invasive nature. Thus, chemotherapy still is the mainstay in the treatment of glioma after surgery. However, the natural blood-brain barrier (BBB) greatly restricts the penetration of chemotherapeutic agents into the central nervous system. As a front-line anti-glioma agent in clinical, carmustine (BCNU) exerts antitumor effect by inducing DNA damage at the O6 position of guanine. However, the therapeutic effect of BCNU was largely decreased because of the drug resistance mediated by O6-alkylguanine-DNA alkyltransferase (AGT) and insufficient local drug concentrations. To overcome these obstacles, we synthesized a BCNU-loaded hypoxia-responsive nano-micelle with BBB penetrating capacity and AGT inhibitory activity, named as T80-HA-AZO-BG/BCNU NPs. In this nano-system, Tween 80 (T80) serves as a functional coating on the surface of the micelle, promoting transportation across the BBB. Hyaluronic acid (HA) with active tumor-targeting capability was linked with the hydrophobic O6-benzylguanine (BG) analog via a hypoxia-sensitive azo bond. Under hypoxic tumor microenvironment, the azo bond selectively breaks to release O6-BG as AGT inhibitor and BCNU as DNA alkylating agent. The synthesized T80-HA-AZO-BG/BCNU NPs showed good stability, favorable biocompatibility and hypoxia-responsive drug-releasing ability. T80 modification improved the transportation of the micelle across an in vitro BBB model. Moreover, T80-HA-AZO-BG/BCNU NPs exhibited significantly enhanced cytotoxicity against glioma cell lines with high AGT expression compared with traditional combined medication of BCNU plus O6-BG. We expect that the tumor-targeting nano-micelle designed for chloroethylnitrosourea will provide new tools for the development of effective glioma therapy.

Elastic full waveform inversion (EFWI) is a powerful technique. However, its strong non-linearity makes it susceptible to converging towards local extremes during the iterative process due to various factors like insufficient low-frequency information or an inadequate initial model. The existing elastic envelope inversion can offer a promising initial model for EFWI when low-frequency information is unavailable, reducing the dependence on both the initial model and low-frequency data. However, its accuracy is affected by the quality of the source wavelet, potentially causing the EFWI to run in the wrong direction if there is a discrepancy between the simulated wavelet and the field wavelet. To address these issues and enhance the reconstruction of large-scale information in the model, we propose a novel approach called source-independent elastic envelope inversion, employing the convolution method. By combining this method with source-independent multiscale EFWI, we effectively establish P- and S-wave velocity models even in situations with inaccurate wavelet information. The results of testing on a portion of the Marmousi2 model demonstrate the effectiveness of this technique for both full-band and low-frequency missing data scenarios.

Abstract Under the effects of complex geological and stress environments, burst hazards continue to be a major challenge for underground space utilization and deep resources exploration as its occurrence can lead to personnel causalities, equipment damage and structural collapse. Considering the stress path experienced by in-situ coal body, cyclic loading appears in quite various forms for instance shearer cutting, overlying strata breakage, hydro-fracturing and blasting, during tunnel, mining and underground space utilizing process. The stability of the underground coal body subject to periodic loading/unloading stress is extremely important for maintain the function of designed engineering structure for waste storage, safe mining, roadway development, gas recovery, carbon sequestration and so on. The mechanical properties of hard rock subject to cyclic fatigue loads has been intensively investigated by many researchers as the rock burst induced by supercritical loads has long been a safety risk and engineering problems for civil and tunneling engineering under deep overburden. More recently, the mechanical properties of coal samples under cyclic fatigue loads is investigated from the aspect of hysteresis, energy dissipation and irreversible damage as the burst hazards of brittle coal is rising in many countries. However, the crack propagation and fracture pattern of brittle coal need more research to understand the micro mechanism of burst incubation subject to cyclic fatigue loads as brittle coal can store more elastic strain energy and rapidly release the energy when its ultimate strength once reached. This research studied the internal crack status corresponding to different cyclic fatigue loading stage of brittle coal samples. The AE monitoring was applied during the uniaxial and cyclic loading process of brittle coal samples to record the crack intensity of samples at different loading stages. The damage evolution curve corresponding to loading status was then determined. The fracture pattern of coal samples determined by micro-CT scan was observed and discussed. It has been found by this paper that brittle coal of uniaxial compression tests demonstrated sudden failure caused by major splitting fracture while that of cyclic fatigue tests experienced progressive failure with mixture fracture network.

The global production of quinoa has been increasing in recent years. In plant-based foods, ultrasound stress has received increasing attention, owing to its ability to enhance the production of primary and secondary metabolites. We studied the effects of ultrasonic stress at the pre-germination stage on the γ-aminobutyric acid (GABA) accumulation and characteristics of nutrition and function in quinoa. The results showed that ultrasonic conditions of 100 W for 4 min promoted an increase in GABA content by 9.15-fold, to 162.47 ± 6.69 mg/100 g·DW, compared to that of untreated quinoa, through promoting a 10.2% and 71.9% increase in the water absorption and glutamate decarboxylase activity of quinoa, respectively. Meanwhile, compared to untreated quinoa, ultrasonic stress at the pre-germination stage enhanced the total phenolic, total flavonoid, and total saponin contents of quinoa by 10.2%, 33.6%, and 90.7%, to 3.29 mg GA/g·DW, 104.0 mg RE/100 g·DW, and 7.13 mg/g, respectively, without decreasing its basic nutritional quality. Ultrasonic stress caused fissures on the surface of quinoa starch particles. Additionally, germination under ultrasonic stress increased the n3 polyunsaturated fatty acids by 14.4%. Furthermore, ultrasonic stress at the pre-germination stage promoted the scavenging of 2,2-diphenyl1-picrylhydrazyl radicals and inhibitions of α-amylase, α-glucosidase, and pancreatic lipase by 14.4%, 14.9%, 24.6%, and 20.0% in vitro, compared to untreated quinoa. The results indicated that the quinoa sprouted via ultrasonic stress could represent a promising method through which to develop nutritionally balanced whole grains rich in GABA, with hypoglycemic and hypolipidemic activities, which could provide theoretical support for the development of functional whole-grain foods based on quinoa.

The lump-grout (LG) material consisted of coarse lumps and pumpable grout has been developed as an alternative infill material to cementitious grout (CG) material in secondary standing support for underground mines. This paper aims to further explore the compressive behaviour of the LG material under variable lateral confinements. A total of 30 LG specimens and 15 CG specimens, either under the active confinement via a Hoek cell or the passive confinement with a fibre-reinforced polymer (FRP) jacket, were prepared and tested. The main test variables included the confining pressure (i.e., 0, 2, 4, 6, 8, 12, 16 MPa) applied by a Hoek cell and the FRP jackets made of variable FRP composites (i.e., CFRP, GFRP and UHMWPE FRP). Test results demonstrated that both the compressive strength and the axial deformation of the LG material were obviously enhanced attributed to effective lateral confinement. The stress path independence assumption was also verified from this research, which provided a feasible access to build the relationship between the active- and passive confinement to the LG material. The in-depth comparison with the CG material, the LG material is much suitable as the infill material for the standing support, in terms of its cost-effectiveness and environmentally friendly.

Abstract For the structural characteristics of power transmission equipment such as bushings, the plug‐in structure is mostly used for current‐carrying connections owing to the large size and long distance at high voltage levels. The contact element strip is the key component of the current‐carrying structure, carrying the combined electrical–thermal effect. Its electrical current‐carrying performance is important. In recent years, discharge failures caused by the overheating failure of electrical connections have occurred from time to time. However, there have been relatively few studies on the failure mechanism of the electrical connection structures of high‐voltage power transmission equipment, such as bushings. In this study, from the perspective of corrosion reaction kinetics, a two‐dimensional phase‐field model of high‐temperature corrosion is established to obtain the carrier concentration distribution in the film. The effects of temperature, gas partial pressure, film thickness, and applied electric field on the growth rate of corrosion reaction film were calculated using the finite element method. At the same time, with the contact element strips used in the bushing as the test object, a corrosion test was carried out in SF6 atmosphere to simulate the high‐temperature corrosion caused by the uneven current carrying of the contacts in actual operating conditions. Combined with the effect of temperature on the film growth rate, the contact area was the most severely corroded location. The simulation can provide a qualitative analysis for the contact degradation test and a new method for studying the factors affecting the corrosion mechanism of contact element strips.

Abstract Background Sleeve lobectomy is recognized as an alternative surgical operation to pneumonectomy because it preserves the most pulmonary function and has a considerable prognosis. In this study, we aimed to investigate the implications of residual status for patients after sleeve lobectomy. Methods In this retrospective cohort study, we summarized 58 242 patients who underwent surgeries from 2015 to 2018 in Shanghai Chest Hospital and found 456 eligible patients meeting the criteria. The status of R2 was excluded. The outcomes were overall survival (OS) and recurrence‐free survival (RFS). We performed a subgroup analysis to further our investigation. Results After the propensity score match, the baseline characteristic was balanced between two groups. The survival analysis showed no significant difference of overall survival and recurrence‐free survival between R0 and R1 groups (OS: p = 0.053; RFS: p = 0.14). In the multivariate Cox analysis, we found that the margin status was not a dependent risk factor to RFS (p = 0.119) and OS (p = 0.093). In the patients of R1, N stage and age were closely related to OS, but we did not find any significant risk variable in RFS for R1 status. In the subgroup analysis, R1 status may have a worse prognosis on patients with more lymph nodes examination. On further investigation, we demonstrated no differences among the four histological types of margin status. Conclusion In our study, we confirmed that the margin status after sleeve lobectomies was not the risk factor to prognosis. However, patients with more lymph nodes resection should pay attention to the margin status.

Abstract Increasing evidence demonstrates that long noncoding RNAs (lncRNAs) play an important role in several pathogenic processes of the kidney. However, functions of lncRNAs in ischemic acute kidney injury (AKI) remain undefined. In this study, global lncRNA profiling indicated that many lncRNA transcripts were deregulated in kidney after ischemia reperfusion (IR). Among them, we identified IRAR (ischemia-reperfusion injury associated RNA) as a potential lncRNA candidate, which was mostly expressed by the tubular epithelial cells (TECs) after IR, involved in the development of AKI. GapmeR-mediated silencing and viral-based overexpression of IRAR were carried out to assess its function and contribution to IR-induced AKI. The results revealed that in vivo silencing of IRAR significantly reduced IR-induced proinflammatory cells infiltration and AKI. IRAR overexpression induced chemokine CCL2, CXCL1 and CXCL2 expression both in mRNA and protein levels in TECs, while, silencing of IRAR resulted in downregulation of these chemokines. RNA immunoprecipitation and RNA pulldown assay validated the association between IRAR and CCL2, CXCL1/2. Further examination revealed that specific ablation of CCL2 in TECs reduced macrophages infiltration and proinflammatory cytokine production, attenuated renal dysfunction in IR mice. Inhibition of CXC chemokine receptor 2 (receptor of CXCL1/2) reduced neutrofils infiltration, but had no overt effect on kidney function. To explore the mechanism of IRAR upregulation in kidney during IR, we analyzed promoter region of IRAR and predicted a potential binding site for transcription factor C/EBP β on IRAR promoter. Silencing of C/EBP β reduced IRAR expression in TECs. A dual-luciferase reporter assay and chromatin immunoprecipitation (ChIP) confirmed that IRAR was a transcriptional target of the C/EBP β. Altogether, our findings identify IRAR as a new player in the development of ischemic AKI through regulating chemokine production and immune cells infiltration, suggesting that IRAR is a potential target for prevention and/or attenuation of AKI.

Abstract Background The genus Ligusticum belongs to Apiaceae, and its taxonomy has long been a major difficulty. A robust phylogenetic tree is the basis of accurate taxonomic classification of Ligusticum. We herein used 26 (including 14 newly sequenced) plastome-scale data to generate reliable phylogenetic trees to explore the phylogenetic relationships of Chinese Ligusticum. Results We found that these plastid genomes exhibited diverse plastome characteristics across all four currently identified clades in China, while the plastid protein-coding genes were conserved. The phylogenetic analyses by the concatenation and coalescent methods obtained a more robust molecular phylogeny than prior studies and showed the non-monophyly of Chinese Ligusticum. In the concatenation-based phylogeny analyses, the two datasets yielded slightly different topologies that may be primarily due to the discrepancy in the number of variable sites. Conclusions Our plastid phylogenomics analyses emphasized that the current circumscription of the Chinese Ligusticum should be reduced, and the taxonomy of Ligusticum urgently needs revision. Wider taxon sampling including the related species of Ligusticum will be necessary to explore the phylogenetic relationships of this genus. Overall, our study provided new insights into the taxonomic classification of Ligusticum and would serve as a framework for future studies on taxonomy and delimitation of Ligusticum from the perspective of the plastid genome.

Abstract There have been significant advancements in medical techniques in the present epoch, with the emergence of some novel operative substitutes. However, the treatment of tracheal defects still faces tremendous challenges and there is, as yet, no consensus on tracheal and carinal reconstruction. In addition, surgical outcomes vary in different individuals, which results in an ambiguous future for tracheal surgery. Although transplantation was once an effective and promising method, it is limited by a shortage of donors and immune rejection. The development of bioengineering has provided an alternative for the treatment of tracheal defects, but this discipline is full of ethical controversy and hindered by limited cognition in this area. Meanwhile, progression of this technique is blocked by a deficiency in ideal materials. The trachea together with the carina is still the last unpaired organ in thoracic surgery and propososal of a favorable scheme to remove this dilemma is urgently required. In this review, four main tracheal reconstruction methods, especially surgical techniques, are evaluated, and a thorough interpretation conducted.

Given a finite group $G$, let $\pi(G)$ denote the set of all primes that divide the order of $G$. For a prime $p\in \pi(G)$, we define $p$-singular elements as those elements of $G$ whose order is divisible by $p$. We denote the proportion of $p$-singular elements in $G$ by ${\mu_p}(G)$. Let $\mu(G) := {\{\mu_p}(G) | p\in \pi(G)\}$ be the set of all proportions of $p$-singular elements for each prime $p$ that divides $|G|$. In this paper we prove if a finite group $G$ has the same set of proportions as a Mathieu simple group $M$, then $G$ is isomorphic to $M$.

As an important electrical connection component in electrical equipment, the strap contact is directly related to the long-term operation stability of equipment. The electrical contact resistance (ECR) of the electrical connection structure is an important indicator for evaluating the reliability of the electrical contact system. In this research, the theoretical calculation of ECR of the strap contacts used by the G-W theoretical model and the fractal theoretical model is improved and compared. After comparison with the experimental measurement values, the rationality and accuracy of the two theoretical models are discussed. The results show that when the load is small (1–3 N), the maximum error of G-W model is 41%, while the fractal model method has a maximum error of 9%. When the load is large (4–10 N), the results of the two are almost the same, and the errors are both within 14%. In summary, the error range of the fractal model is smaller and the change trend is closer to the experimental value, which is suitable for a relatively better ECR analytical calculation theory. The research results can provide a theoretical basis for research on the electrical contact performance of the electrical contact structure of electrical equipment.

Ground surface settlement under subway tunnel construction is one of the main sources of urban ground surface settlement, which may threaten the safety of existing buildings. Therefore, it is necessary to study the influence of subway tunnel construction on the safety and stability of surface subsidence. In the current study, the ground settlement originating from the operation of a tunnel-boring machine (TBM) while excavating a double-line tunnel that underpasses existing buildings is studied. To this end, numerical simulations were carried out and experimental data were analyzed. The boring parameters for the underpass interval section were derived by simulating the construction process and analyzing the TBM parameters in a real project. Then, the influence of thrust force, grouting pressure, and frictional force was considered on the surface settlement. For spatial locations between the existing buildings and the tunnel in the underpass area, the width of the ground surface settlement caused by different excavation sequences of the TBM two-line tunnel was analyzed. The obtained results demonstrate that the performed calculations are consistent with the monitoring data. It is found that the width and depth of the ground surface settlement trough are affected by the distance between the existing buildings and the TBM construction tunnel. However, the settlement location is independent of the excavated sequence but depends on the location of the TBM tunnel and the existing building.

This research reviewed the mechanics and gas desorption properties of intact coal, and tested the crushing work ratios of different intact coals, and then, studied the stress conditions for the failure or crushing of intact coal and the gas demand for the pulverization of intact coal particles. When a real-life outburst case is examined, the required minimum stress for intact coal outburst is estimated. The study concludes that the crushing work ratios of three intact coal samples vary from 294.3732 to 945.8048 J/m2. For the real-life case, more than 2300 MJ of transport work is needed, and 10062.09, 7046.57 and 5895.47 m3 of gas is required when the gas pressure is 1, 2 and 3 MPa, respectively. The crushing work exceeds the transport work and even reaches 13.96 times of the transport work. How to provide such an enormous crushing work is an energy-limiting factor for the outburst in intact coal. The strain energy is needed for the crushing work, and the required minimum stress is over 54.35 MPa, even reaching 300.44 MPa. These minimum stresses far exceed the in-situ vertical and horizontal stresses that can be provided at the 300–700 m mining depth range.

We propose that despite the general positive impact of maintaining political connections, internet utilization generates a disconnecting effect on the impacts of political connections on firm innovation. Using a unique survey dataset of Chinese private enterprises, the present study found that private firm owners’ internet use moderates the relationship between political connections and firm innovation. The present study therefore enriches the literature on the effects of political connections and resource-based view by discovering that internet technology disconnects firms’ political connections and substitutes for the function of political connections on information search and resource acquisition.

Graphene and its derivatives have been a burning issue in the last 10 years. Although many reviews described its application in electrochemical detection, few were focused on food detection. Herein, we reviewed the recent progress in applying graphene and composite materials in food detection during the past 10 years. We pay attention to food coloring materials, pesticides, antibiotics, heavy metal ion residues, and other common hazards. The advantages of graphene composites in electrochemical detection are described in detail. The differences between electrochemical detection involving graphene and traditional inherent food detection are analyzed and compared in depth. The results proved that electrochemical food detection based on graphene composites is more beneficial. The current defects and deficiencies in graphene composite modified electrode development are discussed, and the application prospects and direction of graphene in future food detection are forecasted.

Affected by an insufficient understanding of oxidation characteristics and the CO production mechanism in low-rank coal goaf, the safety management of coal spontaneous combustion (CSC) faces severe challenges. In this study, in-depth research was conducted using ambient temperature oxidation (ATO), temperature-programmed, in situ FTIR experiments and DFT simulation after analyzing the oxidation scenario characteristics of low-metamorphic coal goaf. The results show the oxidation of low-rank coal goaf includes two processes of ATO in the dissipation zone and CSC in the oxidation zone. The CO production of ATO increases with a decrease in coal metamorphic degree, and the risk of CSC is influenced by ATO, with an inhibitory effect before the critical temperature, and an encouraging effect after that. The CO production mechanism of low metamorphic coal goaf from ATO to CSC is established. Before the critical temperature, CO mainly comes from the primary aldehyde functional groups, then peroxide-free radicals participate in the reaction, resulting in the production of a large number of secondary aldehyde functional groups, which leads to the sudden change in CO output. The problem of the abnormal, continuous exceedance of CO in the tailgate corner can be solved by developing an ATO inhibitor, which plays an inhibiting role at ambient temperature and decomposes in the event of CSC.

This paper presents the development of an innovative standing support for underground mines. The main feature of this standing support is its exterior container, a combination of polyvinyl chloride (PVC) with large rupture strain and fibre-reinforced polymer (FRP) with high strength-to-weight ratio. To demonstrate the advantages of this cementitious grout filled PVC-FRP tubular (PFT) standing support, a series of compression tests were conducted. Test variables included the strength of cementitious grout infill material and the thickness of FRP jacket. Compression tests were also conducted on cementitious grout-filled PVC tubular (PT) support and cementitious grout-filled FRP tubular (FT) support. These tests showed that PFT support presents a typical strain-hardening behaviour together with an outstanding axial deformation ability (>20% of the overall height of the support). In addition, the maximum compressive strength of PFT support is much higher than that of the corresponding PT support and FT support. Furthermore, using thicker FRP jacket or high strength cementitious grout material can enhance the load carrying capacity of PFT support. These comparative results indicated that the high performance of PFT support is mainly attributed to the combination of confining constituents (i.e. PVC and FRP) and infill material.

Aristolochic acid nephropathy (AAN) is a type of drug-induced nephropathy and is correlated with a potentially progression of kidney fibrosis. However, whether miR-382 is implicated in macrophage activation in AA-induced kidney fibrosis remains elusive. Here, cell-sorting experiments defined a significant miR-382 enrichment in renal macrophage after AAN 14 days. Then, we found that treatment of AA induced a significant switch in the phenotype of macrophage both in vivo and in vitro. Furthermore, miR-382 knockout (KO) mice and miR-382-/- bone marrow-derived macrophage (BMDM) were subjected to AA induction. We found that both systemic KO and macrophage-specific miR-382 depletion notably suppressed M2-like macrophage activation as well as kidney interstitial fibrosis. Additionally, adoptive transfer of miR-382 overexpression BMDMs into mice promoted AA-induced kidney injury. Moreover, in cultured macrophage, upregulation of miR-382 promoted M2-related gene expression, accompanied by downregulation of signal regulatory protein α (SIRP-α) and activation of signal transducer and activator of transcription 3 (STAT3). The interaction between miR-382 and SIRP-α was evaluated via dual-luciferase assay. Knockdown of SIRP-α upregulated phosphorylated STAT3 at S727 and Y705. Pharmacological inhibition of STAT3 was performed both in vivo and in vitro. Inhibition of STAT3 attenuated AA-induced kidney fibrosis, in parallel to lesser macrophage M2 polarization. Coculture experiments further confirmed that overexpressed miR-382 in macrophage promoted injuries of tubular cells. Luminex bio-chip detection suggested that IL-4 and CCL-5 were critical in the cross talk between macrophages and tubular cells. Taken together, our data suggest that miR-382 is a critical mediator in M2-like macrophage polarization and can be a promising therapeutic target for kidney fibrosis.

Esophageal cancer ranks as the sixth most common cause of cancer death worldwide. Due to the limited efficacy of conventional therapeutic strategies, including surgery, chemotherapy, and radiotherapy, treatments are still far from satisfactory in terms of survival, prompting the search for novel treatment methods. Immune checkpoints play crucial roles in immune evasion mediated by tumor cells, and successful clinical outcomes have been achieved via blocking these pathways. However, only a small fraction of patients can benefit from current immune checkpoint inhibitors targeting programmed cell death ligand-1 (PD-L1) and cytotoxic T-lymphocyte-associated protein-4. Unfortunately, some patients show primary and/or acquired resistance to immune checkpoint inhibitors. Until now, novel immune checkpoint pathways have rarely been studied in esophageal cancer, and there is a great need for biomarkers to predict who will benefit from existing strategies. Herein, we primarily discuss the roles of new immune checkpoints as predictive biomarkers and therapeutic targets for esophageal cancer. In addition, we summarize the ongoing clinical trials and provide future research directions targeting these pathways.

Abstract Background The genus Ligusticum consists of approximately 60 species distributed in the Northern Hemisphere. It is one of the most taxonomically difficult taxa within Apiaceae, largely due to the varied morphological characteristics. To investigate the plastome evolution and phylogenetic relationships of Ligusticum, we determined the complete plastome sequences of eight Ligusticum species using a de novo assembly approach. Results Through a comprehensive comparative analysis, we found that the eight plastomes were similar in terms of repeat sequence, SSR, codon usage, and RNA editing site. However, compared with the other seven species, L. delavayi exhibited striking differences in genome size, gene number, IR/SC borders, and sequence identity. Most of the genes remained under the purifying selection, whereas four genes showed relaxed selection, namely ccsA, rpoA, ycf1, and ycf2. Non-monophyly of Ligusticum species was inferred from the plastomes and internal transcribed spacer (ITS) sequences phylogenetic analyses. Conclusion The plastome tree and ITS tree produced incongruent tree topologies, which may be attributed to the hybridization and incomplete lineage sorting. Our study highlighted the advantage of plastome with mass informative sites in resolving phylogenetic relationships. Moreover, combined with the previous studies, we considered that the current taxonomy system of Ligusticum needs to be improved and revised. In summary, our study provides new insights into the plastome evolution, phylogeny, and taxonomy of Ligusticum species.

A new species Tongoloa arguta (Apiaceae) is described and illustrated in this article. The new species grows in alpine bushes and meadows in south-western China. It resembles T. silaifolia, but differs from the latter by the length of the stem, ultimate segments of leaf and rays of the umbel. Phylogenetic analysis, based on nuclear ribosomal DNA internal transcribed spacer (ITS) sequences, is provided, as well as comparative morphology between related species.

Abstract To satisfy the demand of industrial production, selecting strains suitable for fermentation initiation is necessary. In this study, the effects of mixed‐starter culture including Leuconostoc, Lactobacillus, and Weissella on the quality of Sichuan pickle were discussed. Results showed that mixed‐starter culture can accelerate fermentation and had the highest efficiency for nitrite degradation, that is, the maximum nitrite concentration was 8.97 g/kg on day 1 and decreased to 1.88 mg/kg after 3 days. The mixed‐starter culture improved the sensory properties of pickles, which easily produced acids but had reduced amounts of total acids. The pickle products fermented by the mixed‐starter culture contained increased lactic acid (17.52 g/kg), mannitol (0.62%), umami (35.85), and sweet (11.36) amino acids on day 4. The strains Weissella paramesenteroides C2‐2 and Lactobacillus brevis ZP11‐2 grew well in the mixed‐starter culture fermentation.

Solving environmental problems relies upon cultivating pro-environmental behavior in the society. While the internet has been widely used to facilitate information transmission and communication, it's important to understand its function in promoting pro-environmental behavior. Using the data from the China General Social Survey 2013, the relationship between the use of internet and the individual's pro-environmental behavior is investigated, and overall positive effects are found. The results show that, the influence of internet use is more pronounced on the private pro-environmental behavior when further dividing pro-environmental behavior into private and public types. Moreover, the positive effect of internet use on pro-environmental behavior is more pronounced among low-income and female groups, compared to middle to high income and male counterparts, respectively, when considering the heterogeneity across different groups of individuals. We further explore the plausible channels of providing information, encouraging participation in pro-environmental campaigns and improving social relationships through which internet use facilitates pro-environmental behavior.

Chloroethylnitrosoureas (CENUs) are an important family of chemotherapies in clinical treatment of cancers, which exert antitumor activity by inducing the formation of DNA interstrand crosslinks (dG-dC ICLs). However, the drug resistance mediated by O6-alkylguanine-DNA alkyltransferase (AGT) and absence of tumor-targeting ability largely decrease the antitumor efficacy of CENUs. In this study, we synthesized an azobenzene-based hypoxia-activated combi-nitrosourea prodrug, AzoBGNU, and evaluated its hypoxic selectivity and antitumor activity. The prodrug was composed of a CENU pharmacophore and an O6-benzylguanine (O6-BG) analog moiety masked by a N,N-dimethyl-4-(phenyldiazenyl)aniline segment as a hypoxia-activated trigger, which was designed to be selectively reduced via azo bond break in hypoxic tumor microenvironment, accompanied with releasing of an O6-BG analog to inhibit AGT and a chloroethylating agent to induce dG-dC ICLs. AzoBGNU exhibited significantly increased cytotoxicity and apoptosis-inducing ability toward DU145 cells under hypoxia compared with normoxia, indicating the hypoxia-responsiveness as expected. Predominant higher cytotoxicity was observed in the cells treated by AzoBGNU than those by traditional CENU chemotherapy ACNU and its combination with O6-BG. The levels of dG-dC ICLs in DU145 cells induced by AzoBGNU was remarkably enhanced under hypoxia, which was approximately 6-fold higher than those in the AzoBGNU-treated groups under normoxia and those in the ACNU-treated groups. The results demonstrated that azobenzene-based combi-nitrosourea prodrug possessed desirable tumor-hypoxia targeting ability and eliminated chemoresistance compared with the conventional CENUs.

We aimed to evaluate the inhibitory effect and mechanism of plantaricin YKX on S. aureus. The mode of action of plantaricin YKX against the cells of S. aureus indicated that plantaricin YKX was able to cause the leakage of cellular content and damage the structure of the cell membranes. Additionally, plantaricin YKX was also able to inhibit the formation of S. aureus biofilms. As the concentration of plantaricin YKX reached 3/4 MIC, the percentage of biofilm formation inhibition was over 50%. Fluorescent dye labeling combined with fluorescence microscopy confirmed the results. Finally, the effect of plantaricin YKX on the AI-2/LuxS QS system was investigated. Molecular docking predicted that the binding energy of AI-2 and plantaricin YKX was −4.7 kcal/mol and the binding energy of bacteriocin and luxS protein was −183.701 kcal/mol. The expression of the luxS gene increased significantly after being cocultured with plantaricin YKX, suggesting that plantaricin YKX can affect the QS system of S. aureus.

Given the difficulty of early warning of coal spontaneous combustion caused by continuous abnormal exceedance of CO in the tailgate corner of a low metamorphic coal seam and taking the 1305-working face of the Dananhu No.1 coal mine in Hami, Xinjiang as an example, this paper studies the abnormal CO-exceedance phenomenon based on field measurements, experimental research, and numerical simulation. The research shows that the abnormal CO-exceedance phenomenon is not caused by spontaneous combustion oxidation but by ambient-temperature oxidation of coal in the goaf. Factors, such as higher amounts of residual coal and higher degrees of fragmentation of the goaf, provide opportunities for the ambient-temperature oxidation of residual coal in the 1305 goaf. The 1305 coal oxidation characteristics at ambient temperature are examined, and the abnormal CO-exceedance mechanism is analyzed in depth. A CO-early-warning-limit model in the tailgate corner for coal spontaneous combustion in the 1305 goaf is established, and the scientific problems needing to be solved by further research are also discussed. The relevant research results have an important guiding significance for improving scholars’ understandings of CO exceedance in similar low metamorphic coal seams and the early warning of coal spontaneous combustion.

The temperature of advanced components in aviation and aerospace fields is difficult to obtain timely. In this study, we aimed to investigate microwave backscattering technology combined with the theory of substrate integrated waveguide and resonant cavity to design a wireless passive temperature sensor and explore its potential in this field. We employed silicon carbide and aluminum ceramic as the substrate to make sensors. The interrogation antenna was designed to test the sensor, which could completely cover the working frequency of the sensor and had good radiation characteristics. Based on the test results, the silicon carbide sensor was capable of bearing a temperature limit of about 1000 °C compared to the alumina sensor. From 25 °C to 500 °C, its sensitivity was 73.68 kHz/°C. Furthermore, the sensitivity was 440 kHz/°C in the range of 501 °C to 1000 °C. Moreover, we observed the surface of this sensor by using the scanning electron microscope, and the results showed that the damage to the sensor surface film structure caused by long-term high temperature is the major reason for the failure of the sensor. In conclusion, the performance of the silicon carbide sensor is superior to the alumina sensor.

Cnidium monnieri is an economically important traditional Chinese medicinal plant. In this study, the complete chloroplast (cp) genome of C. monnieri was determined using the Illumina paired-end sequencing, the GetOrganelle de novo assembly strategy, as well as the GeSeq annotation method. Our results showed that the cp genome was 147,371 bp in length with 37.4% GC content and included a large single-copy region (94,361 bp) and a small single-copy region (17,552 bp) separated by a pair of inverted repeat regions (17,729 bp). A total of 129 genes were contained in the cp genome, including 85 protein-coding genes, 36 tRNA genes, and eight rRNA genes. We also investigated codon usage, RNA editing, repeat sequences, simple sequence repeats (SSRs), IR boundaries, and pairwise Ka/Ks ratios. Four hypervariable regions (trnD-trnY-trnE-trnT, ycf2, ndhF-rpl32-trnL, and ycf1) were identified as candidate molecular markers for species authentication. The phylogenetic analyses supported non-monophyly of Cnidium and C. monnieri located in tribe Selineae based on the cp genome sequences and internal transcribed spacer (ITS) sequences. The incongruence of the phylogenetic position of C. monnieri between ITS and cpDNA phylogenies suggested that C. monnieri might have experienced complex evolutions with hybrid and incomplete lineage sorting. All in all, the results presented herein will provide plentiful chloroplast genomic resources for studies of the taxonomy, phylogeny, and species authentication of C. monnieri. Our study is also conducive to elucidating the phylogenetic relationships and taxonomic position of Cnidium.

To investigate the bedding influence on coal mechanical behaviour in underground environments such as coal or rock burst, simulations of dynamic SHPB tests of pre-stressed coal specimens with different bedding angles were carried out using a particle flow code 2-dimensional (PFC2D). Three impact velocities of 4, 8 and 12 m/s were selected to study dynamic behaviours of coal containing bedding planes under different dynamic loads. The simulation results showed that the existence of bedding planes leads to the degradation of the mechanical properties and their weakening effect significantly depends on the angle θ between the bedding planes and load direction. With θ increaseing from 0° to 90°, the strength first decreased and subsequently increased and specimens became most vulnerable when θ was 30° or 45°. Five failure modes were observed in the specimens in the context of macro-cracks. Furthermore, energy characteristics combined with ultimate failure patterns revealed that maximum accumulated energy and failure intensity have a positive relation with the strength of specimen. When bedding planes were parallel or perpendicular to loading direction, specimens absorbed more energy and experienced more violent failure with increased number of cracks. In contrast, bedding planes with θ of 30° or 45° reduced the specimens’ ability of storing strain energy to the lowest with fewer cracks observed after failure. Keywords: Static–dynamic coupled loads, SHPB, Coal bedding angle, Strain energy, PFC2D

Coal burst is the violent failure of overstressed coal, and it is often accompanied by sound, coal ejection and seismic events. It is subsequently recognized as a serious safety risk of Australia after double fatalities coal burst happened at Austar Coal Mine. Considering the increasing trend of coal burst severity and frequency with mining depth, it is an urgent task to develop the coal burst risk assessment methods for Australia underground coal mines. Coal burst propensity index method is a widely used method of burst risk evaluation of coal as it is summed up from the coal burst research and practice of many countries. This paper presents the experimental and theoretical research of coal burst propensity index method for coal burst risk assessment in Australia. The definition of four indexes including elastic strain energy index (WET), bursting energy index (KE), dynamic failure time (DT) and uniaxial compression strength (RC) is introduced in the first part. Then, the standard laboratory test process and test parameter of coal burst propensity index is presented. DT test is conducted with 0.3 mm/min displacement control loading rate while other test is with 0.5 mm/min. Besides, modified data processing and risk classification method of test are proposed. Differentiate analysis of stress-strain curve is adopted in the data processing of DT and KE index. A four level risk classification form of burst risk is recommended for Australian underground coal mines. Finally, two likely improvement methods of WET test, including volumetric strain indicator method and theoretical calculation method, are discussed. Keywords: Coal burst, Coal burst propensity, Risk evaluation, Underground mining

Hard rock Tunnel Boring Machines (TBMs) engaging disc cutters as cutting tools have been employed in considerable underground coal mines to accommodate the requirement of more stone drivage as operations are going deeper. This study conducted a set of disc cutter indentation tests to explore the influence of confining stresses on rock fragmentation, thrust force, and penetration energy on sandstone, which is commonly encountered in underground coal mines. The test results show that there exists a critical confining stress, under which the maximum thrust force and penetration energy keep increasing with confining stress mounting while the maximum thrust force and penetration energy will decrease or flatten if it is surpassed. By combining with previous studies and comparing the critical confining stress values to the rock mechanical properties’ values, the critical value is most likely to be of cohesion. For subsurface rock fragmentation, the Constant Cross Section (CCS) disc cutter indentation has denser cracks and their orientations are more lateral than those under the V shape one; the V shape disc cutter indentation is less sensitive to confining stresses, with no notable increase of crack number and crack reorientation with increasing confinement. Thus, the CCS disc cutter is more favorable than the V shape one from the perspective of rock fragmentation under confining stresses.

In this study, stress solution for rock mass containing two rectangular openings was calculated based on the Schwarz alternating method to investigate the stress distribution in rock mass around openings with different layouts. In addition, large-scale numerical models were further established for the two-opening system by means of the PFC-FLAC coupling method, in which the stress evolution, failure patterns, and acoustic emission (AE) events were presented. With the combination of analytical and numerical solutions, the interaction mechanism between two openings under different layouts was discussed from the perspective of stress and failure. The result shows that the confining stress within a certain range contributes to relieving tensile stress concentration around openings. The stress condition within the connecting area and coalescence pattern between two adjacent openings is dominated by their layout. Compared with small-size rock specimens in laboratory tests, the failure patterns around openings show a better agreement with the stress concentration characteristics determined by analytical stress solutions.

Coal and gas outburst is the extreme instability caused by stress, gas, and coal. In this review article, dominant factors and inducing factors of outburst were summarized; geologic features of typical outburst cases and the effects of tectonic movement on outbursts were analyzed; the outburst stages with considerations to geologic factors were divided. It was found that inducing factors, including buried depth, tectonic movement, gas composition, coal seam conditions, overlying/underlying rock conditions, and mining mode, control the outburst by influencing the dominant factors (stress, gas, and coal). Among them, tectonic movement is the key of outburst. Influenced by tectonic movement, the primary structure of coals is damaged/pulverized due to the tectonic stress and unique tectonic mode, resulting in the formation of tectonic coals. When external dynamic factors are changed, tectonic coals are crucial to outburst control for its evolution of porous structure as well as the unique mechanical behaviors and gas flowing responses. Besides, the preparation stage of outburst includes the tectonic process and mining process. The former one refers to the restructuring process of the original coal-bearing strata by tectonic movement, while the mining process is the prerequisite of outburst and it refers to the disturbance of human mining activities to the initial coal seams. It is suggested that more work is required on geological factors of outburst, and a few research areas are proposed for future research.

Renal ischemia-reperfusion (I/R) can induce oxidative stress and injury via the generation of reactive oxygen species (ROS). Renal proximal tubular cells are susceptible to oxidative stress, and the dysregulation of renal proximal tubular cellular homeostasis can damage cells via apoptotic pathways. A recent study showed that the generation of ROS can increase perilipin 2 (Plin2) expression in HepG2 cells. Some evidence has also demonstrated the association between Plin2 expression and renal tumors. However, the underlying mechanism of Plin2 in I/R-induced acute kidney injury (AKI) remains elusive. Here, using a mouse model of I/R-induced AKI, we found that ROS generation was increased and the expression of Plin2 was significantly upregulated. An in vitro study further revealed that the expression of Plin2, and the generation of ROS were significantly upregulated in primary tubular cells treated with hydrogen peroxide. Accordingly, Plin2 knockdown decreased apoptosis in renal proximal tubular epithelial cells treated with hydrogen peroxide, which depended on the activation of peroxisome proliferator-activated receptor α (PPARα). Overall, the present study demonstrated that Plin2 is involved in AKI; knockdown of this marker might limit apoptosis via the activation of PPARα. Consequently, the downregulation of Plin2 could be a novel therapeutic strategy for AKI.

Spontaneous combustion of residual coal in longwall goaf is a long standing hazard. Airflow leakage into goaf is a major driver to the hazard and this issue deteriorates where longwalls are operating in multiple seams and shallow covers because mining-induced cracks are very likely to draw fresh airflow into goaf due to presence of pressure differential between longwall face and surface. To study the problem more critically, a ventilation simulation package “Ventsim” is used to conduct a case study from Bulianta colliery. It was found that isolating and pressurizing active longwall panel can mitigate the problem and the pressure differential can be adjusted by varying performance of auxiliary fan and resistance of ventilation regulator. A booster ventilation system can also mitigate the problem by adjusting fan duties. Ventilation simulation is a powerful tool to study spontaneous combustion control in underground coal mine. Keywords: Ventilation simulation, Spontaneous combustion, Longwall operation, Pressure differential, Ventsim

In this study, the triangle interpolation method for the calculation of mapping functions of plates containing an opening with arbitrary shapes is investigated with an improved method for point adjudgment during iterations. Afterwards, four kinds of openings with typical shapes are considered and the mapping functions for them are calculated, based on which the influence of calculation parameters such as iteration time and the number of terms on the accuracy of mapping function is discussed. Finally, the stress around an inverted U-shaped opening and around an arched opening under different far-field stress conditions is calculated and the effect of opening shape and lateral pressure coefficient on stress distribution and rock mechanical behaviors is further analyzed combined with the discrete element method (DEM) numerical simulation. The result shows that the stability and failure pattern of the rock mass is correlated with the stress around the opening, which is affected by the opening shape. The existence of opening also greatly reduces the enhancing influence of confining stress on rock specimen.

Large scale open cut coal mining operations have significant impacts to groundwater in surrounding areas in both active and post-mining phases. The prediction of water inflows into a surface mine excavation is one of the many components involved in mine design phase. Groundwater performance also reacts to mining activities from the operational, economic and safety implications perspective. Under NSW planning legislation, as part of the comprehensive risk assessment, a groundwater impact assessment has to be conducted for a coal project to predict and mitigate the impacts in consideration of the government requirements. In this paper, the groundwater assessment modelling of mine pits was discussed in predicting of groundwater inflows and reviewing analytical and numerical approaches. A methodology of groundwater impact assessment for an open cut mine in NSW with a three-dimensional groundwater flow model Modflow Surfact demonstrated its functions in simulating the project’s impacts on the groundwater regime. The key findings with mitigations are discussed and recommended in the paper to reduce impacts on groundwater and fulfil regulation requirements in NSW. Keywords: Open cut coal mine, Groundwater impact assessment, Mining exposure area, Groundwater modelling methodology