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Abstract With the application of new technologies for coal mine gas control, it has been increasingly urgent to apply the fixed‐point closed sampling (FPCS) technology for accurate measurement of coal seam gas content. In this study, gas desorption during FPCS was analyzed. In addition, gas desorption experiments and COMSOL simulations were conducted on coal particles. Furthermore, the gas desorption law during FPCS was compared with that under atmospheric pressure. The results show that Sun's formula can effectively characterize the gas desorption law during FPCS, and the i value remains unchanged when the gas desorption curve is fitted with Sun's formula. On this basis, a specific method for calculating gas loss during FPCS by using Sun's formula was proposed. The research findings are expected to provide a theoretical basis for accurate measurement of coal seam gas content by means of FPCS.

Abstract Objective Buccal mucosa cancer (BMC) is one of the most common oral cancers and has poor prognosis. The study aimed to develop and validate nomograms for predicting the 1‐, 3‐, and 5‐year overall survival (OS) and cancer‐specific survival (CSS) of BMC patients. Methods We collected and reviewed information on BMC patients diagnosed between 2004 and 2019 from the Surveillance Epidemiology and End Results database. Two nomograms were developed and validated to predict the OS and CSS based on predictors identified by univariate and multivariate Cox regression. An extra external validation was further performed using data from Sun Yat‐sen Memorial Hospital (SYSMH). Results A total of 3154 BMC patients included in this study were randomly assigned to training and validation groups in a 2:1 ratio. Independent prognostic predictors were identified, confirmed, and fitted into nomograms for OS and CSS, respectively. The C‐indices are 0.767 (Training group OS), 0.801 (Training group CSS), 0.763 (Validation group OS), and 0.781 (Validation group OS), respectively. Moreover, the nomograms exhibited remarkable precision in forecasting and significant clinical significance, as evidenced by receiver operating characteristic (ROC) curves, calibration curves, and decision curve analyses (DCA). The final validation using our data from SYSMH also showed high accuracy and substantial clinical benefits within the nomograms. The C‐indices are 0.849 (SYSMH group OS) and 0.916 (SYSMH group CSS). These indexes are better than tumor, node, and metastasis stage based on prediction results. Conclusions The nomograms developed with great performance predicted 1‐, 3‐, and 5‐year OS and CSS of BMC patients. Use of the nomograms in clinical practices shall bring significant benefits to BMC patients.

Localized topological modes with high robustness to various perturbations are receiving increasing attention. Recently, zero-order topological vortex modes have been designed in phononic structures, in analogy with zero-energy fermionic states modulated by Jackiw-Rossi binding mechanism. Such localized modes may have potential applications for biosensing, bioimaging and on-chip communication. In this work, we propose a pillared phononic plate with a Kekulé distortion of pillars position to bind topological modes at a vortex core via dispersion engineering. The phase winding and amplitude diagrams of the topological vortex mode are observed experimentally. It is found that existence of vibration peaks and corresponding mode patterns are strongly robust against the random perturbation of resonant frequencies of pillars at the vortex core. We further design a topological resonant sensor for mass sensitivity. The frequency of the topological vortex mode is almost linearly sensitive to added small mass at the vortex core in terms of mass values and positions. The proposed pillared plates provide a platform for potential applications such as energy localization and harvesting, remote health monitoring.

Abstract The natural frequency of coal is one of the important technical parameters for the application of the permeability enhancement technology of coal and rock forced vibration. Aiming at exploring the dominant frequency of the permeability enhancement technology of coal vibration excited by vibration wave, the model of coal vibration excited by simple harmonic wave (SHW) was constructed. Furthermore, considering the three main control parameters, i.e., excitation force, coal sample size and mechanical parameters, the response characteristics of coal vibration excited by SHW were simulated and calculated. The calculation results demonstrate that when the frequency of excitation force equals the natural frequency of coal, the vibration occurs and the peak values of response parameters all increase significantly. The peak acceleration response of coal increases with the increase of excitation force, whereas it decreases with the increase of coal size. Under the same SHW excitation force, the mechanical parameters of coal determine the vibration response characteristics of coal, and the natural frequency of coal is proportional to the elastic modulus. Finally, the variation law of natural frequency response characteristics of coal vibration excited by SHW was verified by the response experiment on coal vibration under SHW excitation and related test results. The research results can serve as a theoretical basis for the application of the permeability enhancement technology of coal vibration excited by vibration wave.

How crop domestication mediates root functional traits and trait plasticity in response to neighboring plants is unclear, but it is important for selecting potential species to be grown together to facilitate P uptake. We grew two barley accessions representing a two-stage domestication process as a sole crop or mixed with faba bean under low and high P inputs. We analyzed six root functional traits associated with P acquisition and plant P uptake in five cropping treatments in two pot experiments. The spatial and temporal patterns of root acid phosphatase activity were characterized in situ with zymography at 7, 14, 21, and 28 days after sowing in a rhizobox. Under low P supply, wild barley had higher total root length (TRL), specific root length (SRL), and root branching intensity (RootBr) as well as higher activity of acid phosphatase (APase) in the rhizosphere, but lower root exudation of carboxylates and mycorrhizal colonization (MC), relative to domesticated barley. In response to neighboring faba bean, wild barley exhibited larger plasticity in all root morphological traits (TRL, SRL, and RootBr), while domesticated barley showed greater plasticity in root exudates of carboxylates and colonization by mycorrhiza. Wild barley with greater root morphology-related trait plasticity was a better match with faba bean than domesticated barley, indicated by higher P uptake benefits in wild barley/faba bean than domesticated barley/faba bean mixtures under low P supply. Our findings indicated that the domestication of barley disrupts the intercropping benefits with faba bean through the shifts of root morphological traits and their plasticity in barley. Such findings provide valuable information for barley genotype breeding and the selection of species combinations to enhance P uptake.

Introduction: The initial velocity of gas diffusion (ΔP) of coal is an important index to characterize the outburst risk of coal, and temperature is an important factor affecting the determination of initial velocity of gas diffusion. However, how to control the temperature during ΔP determination remains a significant challenge. Methods: In this paper, an experimental system for ΔP testing under temperature-controlled conditions was constructed, and the effect of temperature on the ΔP determination results was further explored by accurately controlling the temperature of the testing system. Results: The results show that the temperature change will affect the determination result of ΔP in the range of 13°C–40°C, and the determination results do not show obvious regularity. Discussion: The main reasons for the analysis are as follows: during the determination of ΔP, although the higher the temperature is, the faster the speed of gas diffusion and the greater the amount of gas diffusion and the pressure produced in the first 60 s, but the smaller the amount of gas adsorption before release. There is a situation of mutual offset between the two, resulting in the fluctuation of ΔP determination results. It is concluded that the temperature change will affect the determination of the initial velocity of gas diffusion, and when ΔP is measured, the temperature of the experimental system should be consistent with the actual temperature of the sampled coal body as far as possible, so as to increase the reliability of the measured results for the prediction of coal and gas outburst. This paper provides an experimental basis for clarifying the industry standard of temperature related to ΔP.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignant tumors with a poor prognosis. Type X collagen α 1 chain (COL10A1), a member of the collagen family, is a gene associated with the progression of a variety of human tumors, but the specific function and molecular mechanism of COL10A1 in pancreatic cancer remain unclear. Our study found that COL10A1 is highly expressed in pancreatic cancer cells and tissues, and its high expression is related to poor prognosis and some clinicopathological features, such as tumor size and differentiation. Biological functional experiments showed that overexpression of COL10A1 enhanced the proliferation and migration of PDAC cells. Interestingly, discoid protein domain receptor 2 (DDR2), the receptor of COL10A1, is regulated by COL10A1. We found that the COL10A1-DDR2 axis activates the mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway, which leads to epithelial-mesenchymal transformation (EMT) and accelerates the progression of pancreatic cancer. In summary, COL10A1 regulates PDAC cell proliferation and MEK/ERK signaling pathways by binding to DDR2 to promote migration, invasion and EMT. Our study suggested that COL10A1 might be a critical factor in promoting PDAC progression. More research is needed to confirm COL10A1 as a potential biomarker and therapeutic target for PDAC.

Abstract Joule heats which are generated by coals in an applied electric field are directly correlated with variation resistivity of electrical parameters of coals. Moreover, the joule heating effect is closely related with microstructural changes and relevant products of coal surface. In the present study, a self-developed applied direct current (DC) field was applied onto an experimental system of coals to investigate variation resistivity of electrical parameters of highly, moderately and lowly metamorphic coal samples. Moreover, breakdown voltages and breakdown field intensities of above three coal samples with different metamorphic grades were tested and calculated. Variation resistivity of electrical parameters of these three coal samples in 2 kV and 4 kV DC fields were analyzed. Results show that internal current of all coal samples increases continuously and tends to be stable gradually after reaching the “inflection point” at peak. The relationship between temperature rise effect on anthracite coal surface in an applied DC field and electrical parameters was discussed. The temperature rise process on anthracite coal surface is composed of three stages, namely, slowly warming, rapid warming and slow cooling to stabilize. The temperature rise effect on anthracite coal surface lags behind changes of currents which run through coal samples. There’s uneven temperature distribution on anthracite coal surface, which is attributed to the heterogeneity of coal samples. In the experiment, the highest temperature on anthracite coal surface 65.8 ℃ is far belower than the lowest temperature for pyrolysis-induced gas production of coals 200 ℃. This study lays foundations to study microstructural changes and relevant products on coal surface in an applied DC field.

Protective layer mining (PLM) is one of the most effective regional measures against gas outburst, and the most preferred technique to prevent and control gas outburst. This paper attempts to disclose the effect of close-range PLM in Hezhuang Coal mine, Western Henan Coalfield. Firstly, coal seam I7 was selected as the lower protective layer, and coal seam II1 was taken as the overlying coal seam. Considering the situation of actual production, a simulation model for lower PLM was established on Fast Lagrangian Analysis of Continua in 3 Dimensions (FLAC3D). The established model was adopted to simulate the mining of the working face 11030# of the lower protective layer (I7) at the mining depth of 50, 100, 200 and 250 m, respectively. Through the simulation, the authors summarized the laws of stress evolution and deformation of the working face 11030# of the overlying coal seam (II1) in the upper part of the stope. The research results are as follows: After the lower PLM, the stress distribution of 11030# II1 in the strike direction can be divided into three parts from the open-off cut to the stopping line: original stress zone, pressure relief zone and stress concentration zone; the stress distribution of 11030# II1 in the dip direction can also be divided into the three parts from the top to the bottom. However, the stress distribution in the dip direction is less uniform than that in the strike direction. Meanwhile, the 11030# II1 had an unobvious deformation in the original stress zone, compressive deformation in the stress concentration zone, and expansive deformation in the pressure relief zone; the maximum expansive deformation was observed in the middle of the pressure relief zone. The research results lay the theoretical basis for engineering application of lower PLM.

How to endow diverse functions for lightweight structures without increasing mass has always been a major challenge (e.g., to have simultaneous high static stiffness and extreme-low dynamic stiffness in one structure) from both fundamental science and engineering application. In this work, Archimedean spiral metastructures are proposed for low-frequency vibration isolation by combining a double-layer corrugated sandwich core and two spiral metamaterial plates, which the former provides lightweight and high static load-bearing properties, and the latter possesses deep-subwavelength bandgaps. Both of the two proposed metastructures made of resin and Aluminum show efficient vibration isolation below 150 Hz where the corresponding flexural wavelengths are about 40 times the lattice constant, being a highly compact design for deep-subwavelength vibration control. We further develop a machine learning method to realize on-demand inverse design of the metastructures with targeted bandgap properties. The experimental and numerical results of the bandgaps are highly consistent, and further validate the accuracy of the machine-learning prediction. The slits between the Archimedean spiral arms make the metastructures be possible to further integrate sound absorption and isolation functions in future. The proposed metastructures provide a promising way for potential functional integration devices for vibration and noise control in industries such as aerospace engineering.

The characteristics of pores in anthracite from Guhanshan Coal Mine in the Jiaozuo mining area were tested by the mercury injection method. According to the pore size, pores in the coal sample were classified into gas seepage pores and gas adsorption pores which were in line with the stochastic fractal model and the dendric fractal model, respectively. Besides, the fractal characteristics of adsorption pores were analyzed by using a dendric fractal model, and the influence law of the tortuosity fractal dimension Dt on the gas adsorption capacity was obtained. The research results show that the amount of mercury injected into each experimental coal sample is directly proportional to its porosity, but has no obvious correlation with specific surface area. Seepage pores with sizes over 65 nm fit the stochastic fractal model, and their fractal dimension D increases with the increase of specific surface area. Adsorption pores with sizes of below 65 nm fit the dendric fractal model, and their tortuosity fractal dimension Dt is positively correlated with the specific surface area. Through the gas adsorption experiment on coal samples, it is found that a larger Dt corresponds to a stronger gas adsorption capacity. The research results can provide a theoretical basis for elucidating the gas adsorption characteristics of anthracite from a microscopic point of view.

Gliomas are malignant tumors that originate from the central nervous system. The aldehyde dehydrogenase family has been documented to affect cancer progression; however, its role in gliomas remains largely unexplored. Bulk RNA-seq analysis and single-cell RNA-Seq analysis were performed to explore the role of the aldehyde dehydrogenases family in gliomas. Training cohort contained The Cancer Genome Atlas data, while data from Chinese Glioma Genome Atlas and Gene Expression Omnibus were set as validation cohorts. Our scoring system based on the aldehyde dehydrogenases family suggested that high-scoring samples were associated with worse survival outcomes. The enrichment score of pathways were calculated by AUCell to substantiate the biofunction prediction results that the aldehyde dehydrogenases family affected glioma progression by modulating tumor cell proliferation, migration, and immune landscape. Tumor immune landscape was mapped from high-scoring samples. Moreover, ALDH3B1 and ALDH16A1, two main contributors of the scoring system, could affect glioblastoma cell proliferation and migration by inducing cell-cycle arrest and the epithelial-mesenchymal transition. Taken together, the aldehyde dehydrogenases family could play a significant role in the tumor immune landscape and could be used to predict patient prognosis. ALDH3B1 and ALDH16A1 could influence tumor cell proliferation and migration.

The difficulty in enhancing the low permeability of deep coal seams is the key problem restricting gas extraction. The technology of coal rock resonance and permeability enhancement excited by vibration wave is hailed as a new technology to enhance coal seam permeability. In particular, the effect of resonance and permeability enhancement is remarkable when the excitation frequency is exactly the same as the natural frequency of coal. In order to promote the application of the technology, the first step is to explore the variation characteristics of coal natural frequency and its influencing factors. In this study, two mathematical models of coal natural frequency were established, and the variations and influencing factors of coal natural frequency were discussed through an experiment on the natural frequency of coal. The results show that coal vibration has multiorder natural frequency which grows with the increase of the order. In addition, the natural frequency of coal is closely related to its elastic modulus, density, size, mass, stiffness, and other physical and mechanical parameters. The larger the coal size and mass are, the lower the natural frequency would be. The natural frequency parallel to the bedding plane is higher than that perpendicular to the bedding plane. For the saturated coal sample, moisture changes its density and reduces its elastic modulus. Consequently, its natural frequency is lower than that of the dried coal sample. The difference of organic matter and mineral content coal of different rank affects the physical and mechanical properties of coal, which leads to the difference in natural frequency of different-rank coals. The natural frequencies of different-rank coal show bituminous > anthracite > lignite. The natural frequencies of coal samples under different influencing factors are all tens of Hz. Thus, the vibration excitation of coal under the low-frequency condition is the focus of future research. The study can provide a theoretical basis for the technology of coal resonance and permeability enhancement excited by vibration wave.

BackgroundLong non-coding RNAs (lncRNAs) have been indicated to play critical roles in gastric cancer (GC) tumorigenesis and progression. However, their roles in GC remain to be further elucidated.MethodsRT-qPCR and fluorescence in situ hybridzation (FISH) were conducted to detect the expression of lncRNA NEAT1 in GC tissues and cell lines. Gene Set Enrichment Analysis (GSEA) was performed to screen out potential phenotypes and pathways that NEAT1 may participate in. NEAT1-silenced AGS and MGC803 cells were constructed and a series of functional experiments to investigate the roles of NEAT1 in GC angiogenesis both in vitro and in vivo. RNA pull down and luciferase reporter assays were utilized to illustrate the mechanisms underlying the functions of NEAT1 in GC.ResultsWe observed that NEAT1 was upregulated in most GC specimens and cell lines. NEAT1 high was correlated with poor prognosis of GC patients. In vitro experiments showed that NEAT1 promoted GC angiogenesis by enhancing proliferation, migration, and tube formation ability of endothelial cells. Mechanism researches revealed that NEAT1 could competitively sponge miR-17-5p which targeted TGFβR2 directly. Subsequently, activate TGFβ/Smad pathway by following with upregulation of a series of classical proangiogenic factors especially VEGF.ConclusionThe study unveiled that the LncRNA NEAT1/miR-17-5p/TGFβR2 axis is a novel mechanism in GC angiogenesis. Disrupting this axis may be a potential strategy for GC treatment.

The mechanical analog to the topological insulators brings anomalous elastic wave properties which diversifies classic wave functions for potential broad applications. To obtain topological mechanical wave states with good quality at desired frequency ranges, it needs repetitive trials of different geometric parameters with traditional forward designs. In this work, we develop an inverse design of topological edge states for flexural wave using machine learning method which is promising for instantaneous design. Nonlinear mapping function from input targets to output desired parameters are adopted in artificial neural networks where the data sets for training are generated by the plane wave expansion method. Topological edge states are then realized and compared for different bandgap width conditions with such inverse designs, proving that wide bandgap can promote the confinement of the topological edge states. Finally, direction selective propagations with sharp turns are further demonstrated as anomalous wave behaviors. The machine learning inverse design of topological states for flexural wave provides an efficient way to design practical devices with targeted needs for potential applications such as signal processing, sensing and energy harvesting.

Adsorption characteristics of coalbed methane (CBM) are significant to investigate the absorption of coal, shale, and porous media. In particular, adsorption characteristics of CH4, CO2, and H2O play an important role in predicting CBM output and geologic sequestration potentials of CO2 in research fields of CO2-enhanced CBM recovery (CO2-ECBM) and sequestration of CO2. In this work, adsorption characteristics of CH4, CO2, and H2O in lignite molecules were simulated through the grand canonical Monte Carlo (GCMC) method and molecular dynamics (MD) method. Research results demonstrated that given the same temperature and pressure, the ultimate adsorption capacity of lignite per unit to H2O is the highest, followed by those of CO2 and CH4 successively. All isothermal adsorption curves conform to the “I-type” characteristics. In the saturated molecular configuration, gas molecules show different distribution patterns at two sides of the lignite molecule chain. Lignite has typical physical adsorption to CH4 and CO2, with adsorption energy provided by nonbonding energy. However, lignite has both physical adsorption and chemical adsorption to H2O, with adsorption energy provided by both nonbonding energy and hydrogen bond energy. High temperature is against adsorption of CH4, CO2, and H2O. Temperature might inhibit adsorption of gas molecules. Research conclusions lay foundations for the exploitation and development of CBM and relevant studies on sequestration of CO2.

In this study, the full-size pore structure characteristics of six different-rank coal samples were investigated and analyzed from three perspectives, namely, pore shape, pore volume, and pore specific surface area, by performing a high-pressure mercury injection experiment and a low-temperature nitrogen adsorption experiment. Next, the full-size pore volumes and pore specific surface areas of the six coal samples were accurately characterized through a combination of the two experiments. Furthermore, the relationships between volatile matter content and pore volume and between volatile matter content and pore specific surface area were fitted and analyzed. Finally, the influences of metamorphic degree on pore structure were discussed. The following conclusions were obtained. The pore shapes of different-rank coal samples differ significantly. With the increase of metamorphic degree, the full-size pore volume and pore specific surface area both decrease first and then increase. Among the pores with various sizes, micropores are the largest contributor to the full-size pore volume and pore specific surface area. The fitting curves between volatile matter content and pore volume and between volatile matter content and pore specific surface area can well reflect the influence and control of metamorphic degree on pore volume and pore specific surface area, respectively. With the increase of volatile matter content, the pore volume and the pore specific surface area both vary in a trend resembling a reverse parabola.

A novel carbon dioxide (CO2) gas sensor based on capillary array is presented. The capillary array is composed of 51 capillaries and modified by fluorescent dye 8-hydroxy-1,3,6-pyrenetrisulfonic acid trisodium salt (HPTS, PTS−) and tetraoctylammonium cation (TOA+) doped porous ethyl cellulose. A Y-fiber is used to transmit exciting light and fluorescence. A fiber optic pigtail-contained spectrophotometer is used to collect and deal with optical signals. Due to its structural features, each capillary has the two rolling-up layers of inner and outer sensing films, which make the 2 cm long capillary array has large sensing area about 12.81 cm2 and the fluorescence signal easily be collected. The sensing probe has advantages such as small volume, compact structure and large sensing area. The results demonstrate that the sensor has a linear response in the CO2 volume ratio range from 0 to 10%. Keywords: Carbon dioxide chemical sensor, Fluorescence sensor, Capillary array

Determining the width of the stress relief zone on roadway surrounding rocks is the premise to optimize drilling borehole effect and increase gas extraction efficiency. In this study, a new width measurement method of the stress relief zone on the roadway surrounding rocks was proposed, which determined the width according to gas pressure attenuation speeds in roadway boreholes at different depths. Then, the variation curve of the gas pressure in boreholes at different depths with the time was gained through a field test. On this basis, laws of the gas pressure attenuation and the gas transmission and loss in boreholes at different depths were explored through a numerical simulation based on COMSOL Multiphysics, thus concluding the stress on roadway surrounding rocks, the distribution of plastic zones, and the stress-permeability relation. The scientificity of the proposed method was illustrated theoretically. Finally, the proposed method was verified by the field test data and numerical simulation results of the gas extraction at different sealing depths. Research results demonstrate that the pressure in boreholes attenuates in the logarithmic function pattern. The attenuation speed decreases with the increase of the drilling depth. The width of the stress relief zone on roadway surrounding rocks in the studied area was determined to be about 11 m according to the proposed method. Both the numerical simulation and the field test of the gas extraction efficiency prove the feasibility and validity of the proposed method in determining the sealing depth of the borehole for the gas extraction. Research conclusions are of important significance to enrich width measurement methods of the stress relief zone on roadway surrounding rocks and to optimize sealing parameters of underground boreholes for gas extraction.

Developing an efficient non-noble catalyst for CO oxidation with high catalytic activity remains a challenge for practical applications. In this work, CuO nanorods decorated reduced graphene oxide (RGO) nanocatalysts were prepared via a facile one-step hydrothermal method. The structure and morphology of the as-prepared samples were characterized by XRD, Raman spectroscopy, SEM, TEM, and X-ray photoelectron spectroscopy (XPS). The analysis results show that CuO nanorods were successfully deposited on the surface of RGO sheets with the length of 250–500 nm. The catalytic properties of the as-prepared catalysts for CO oxidation were evaluated by using a microreactor-gas chromatograph (GC) system. The as-prepared RGO–CuO nanocatalysts exhibited high activity for CO oxidation, and the 10 wt % reduced graphene oxide content catalyst can achieve CO total oxidation at 165 °C.

Serial capture affinity purification (SCAP) is a powerful method to isolate a specific protein complex. When combined with cross-linking mass spectrometry and computational approaches, one can build an integrated structural model of the isolated complex. Here, we applied SCAP to dissect a subpopulation of WDR76 in complex with SPIN1, a histone reader that recognizes trimethylated histone H3 lysine4 (H3K4me3). In contrast to a previous SCAP analysis of the SPIN1:SPINDOC complex, histones and the H3K4me3 mark were enriched with the WDR76:SPIN1 complex. Next, interaction network analysis of copurifying proteins and microscopy analysis revealed a potential role of the WDR76:SPIN1 complex in the DNA damage response. Since we detected 149 pairs of cross-links between WDR76, SPIN1, and histones, we then built an integrated structural model of the complex where SPIN1 recognized the H3K4me3 epigenetic mark while interacting with WDR76. Finally, we used the powerful Bayesian Integrative Modeling approach as implemented in the Integrative Modeling Platform to build a model of WDR76 and SPIN1 bound to the nucleosome. [ABSTRACT FROM AUTHOR]