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Using ANSYS/LS-DYNA finite element software, a rock RHT damage constitutive model is used to conduct numerical simulation experiments on the dynamic compression of coal SHPB under different strain rates for the Furong Baijiao coal in Yibin, Sichuan. Firstly, based on the determination method of RHT constitutive model parameters for relevant rocks and the RHT parameter values for Riedel concrete, the optimal parameters of the coal RHT dynamic compression constitutive model are determined through 3 levels of 27 sets of orthogonal experiments under different dynamic strain rates and sensitivity analysis of 13 uncertainty parameters. Secondly, based on the comparison and analysis of numerical simulation experiments and indoor experiments, it is found that the stress-strain curves obtained from the two types of experiments were in good agreement. The numerical simulation test results meet the two assumptions of one-dimensional stress and stress uniformity in SHPB compression test, and the numerical simulation test has a certain degree of reliability. Finally, the RHT damage constitutive model is used to explore the dynamic mechanical properties of coal energy evolution law during the asymptotic deformation and failure process: The research results indicate that the RHT damage constitutive model can better simulate the dynamic deformation and failure process of, and the corresponding mechanical properties and energy evolution process are consistent with the laboratory tests; The RHT model parameters of coal show an increasing trend with the increase of strain rate, and the sensitivity is greatly different. As the strain rate increases from 29.12 s−1 to 95.69 s−1, RHT parameters gc*、N、ft*、n and pco are most sensitive to the final simulation effect of coal, while the parameters pco、ξ、fs*、pco and Q0 are the least sensitive; With the increase of strain rate, the resistance to deformation of coal is obviously enhanced, the degree of fragmentation is more intense, and the peak compressive strength and dynamic strength factor DIF value increase exponentially; The dynamic energy evolution process of coal has obvious stages. Dynamic characteristic stress division based on the obvious stages of dynamic energy evolution process of coal. It is found that the corresponding characteristic energy increases first, then decreases, and then tends to be stable. The dynamic elastic energy storage capacity and limit energy storage capacity of coal should also be enhanced with the increase of strain rate.

Abstract Background This study aimed to explore the clinical significance of immunogenic cell death (ICD) in acute myeloid leukemia (AML) and its relationship with the tumor immune microenvironment characteristics. It also aimed to provide a potential perspective for bridging the pathogenesis of AML and immunological research, and to provide a theoretical basis for precise individualized treatment of AML patients. Methods Firstly, we identified two subtypes associated with ICD by consensus clustering and explored the biological enrichment pathways, somatic mutations, and tumor microenvironment landscape between the ICD subtypes. Additionally, we developed and validated a prognostic model associated with ICD-related genes. Finally, we conducted a preliminary exploration of the construction of disease regulatory networks and prediction of small molecule drugs based on five signature genes. Results Differentially expressed ICD-related genes can distinguish AML into subgroups with significant differences in clinical characteristics and survival prognosis. The relationship between the ICD- high subgroup and the immune microenvironment was tight, showing significant enrichment in immune-related pathways such as antibody production in the intestinal immune environment, allograft rejection, and Leishmaniasis infection. Additionally, the ICD- high subtype showed significant upregulation in a variety of immune cells such as B_cells, Macrophages_M2, Monocytes, and T_cells_CD4. We constructed a prognostic risk feature based on five signature genes (TNF, CXCR3, CD4, PIK3CA and CALR), and the time-dependent ROC curve confirmed the high accuracy in predicting the clinical outcomes. Conclusion There is a strong close relationship between the ICD- high subgroup and the immune microenvironment. Immunogenicity-related genes have the potential to be a prognostic biomarker for AML.

The passively Q-switched mode-locked (QML) operation of a Tm:CaGdAlO4 (Tm:CALGO) bulk laser pumped by a wavelength-tunable Ti:sapphire oscillator using molybdenum disulfide (MoS2) as a saturable absorber was demonstrated. By using an output coupler with 3% transmittance, Q-switched mode-locked operation can be achieved with 3.56 W absorbed pump power. At a pump power of 6.77 W, laser pulses with the maximum average power of 1.44 W were obtained, corresponding to a slope efficiency of 21.3%. The laser delivered pulses centered at 1927 nm with a repetition frequency of 131.6 MHz. The experimental results confirm the promising application of the MoS2 in high-power Q-switched mode-locked solid-state lasers at 2 µm.

Exosomal biomarker detection holds great importance in the field of in vitro diagnostics, offering a non-invasive and highly sensitive approach for early disease detection and personalized treatment. Here, we proposed an “APPROACH” strategy, combining aptamer-mediated proximity ligation assay (PLA) with rolling circle amplification (RCA) and time-resolved Förster resonance energy transfer (TR-FRET) for the sensitive and semi-homogenous detection of exosomal biomarkers. PLA probes consisted of a cholesterol-conjugated oligonucleotide, which anchored to the membrane of an exosome, and a specific aptamer oligonucleotide that recognized a target protein of the exosome; the proximal binding of pairs of PLA probes to the same exosome positioned the oligonucleotides in the vicinity of each other, guiding the hybridization and ligation of two subsequently added backbone and connector oligonucleotides to form a circular DNA molecule. Circular DNA formed from PLA underwent rolling circle amplification (RCA) for signal amplification, and the resulting RCA products were subsequently quantified by TR-FRET. The limits of detection provided by APPROACH for the exosomal biomarkers CD63, PD-L1, and HER2 were 0.46 ng∙μL−1, 0.77 ng∙μL−1, and 1.1 ng∙μL−1, respectively, demonstrating excellent analytical performance with high sensitivity and quantification accuracy. Furthermore, the strategy afforded sensitive detection of exosomal CD63 with a LOD of 1.56 ng∙μL−1 in complex biological matrices, which underscored its anti-interference capability and potential for in vitro detection. The proposed strategy demonstrates wide-ranging applicability in quantifying diverse exosomal biomarkers while exhibiting robust analytical characteristics, including high sensitivity and accuracy.

Tobramycin (TOB) is a broad-spectrum aminoglycoside extensively used as veterinary medicine to treat bacterial infections. However, TOB residue in food and environment may cause great threat to human health. Here, we report, for the first time, the upconversion nanoparticles (UCNPs) for TOB detection based on Förster resonance energy transfer (FRET). The upconversion (UC) luminescence from core-shell structured UCNPs was effectively quenched after addition of MnO2 nanosheets due to the efficient energy transfer from the UCNPs to MnO2 nanosheets. When interacting with TOB, the UC luminescence was restored and increased as a result of coupling between TOB and aptamer, with MnO2 nanosheets dropping off the latter one. The UCNPs@SiO2-MnO2 aptasensors for TOB detection have a good selectivity and sensitivity in a linear range of 10–180 ng mL−1 with a limit of detection (LOD) of 3.04 ng mL−1. The sensors were tested for TOB detection in real samples of liquid milk and fishes and the results are very good and satisfactory. These type of aptasensors are promising for practical applications as they have a high sensitivity, selectivity, low LOD, and are autofluorescence-free.

Introduction: Precisely determining the characteristic stress value of a rock progressive failure process has important theoretical and practical significance for reasonably defining the rock deformation and failure stage, mechanical mechanism, and design parameters.Methods: Based on the energy characteristics in the process of rock deformation and failure, this paper proposes a new method of rock characteristic stress (EGR) around the index of elastic energy storage capacity, elastic energy growth rate, and dissipative energy growth rate. First, the rationality of the new method is verified by the indoor uniaxial and triaxial loading test data of coal and marble. Second, five different determination methods, namely, lateral strain method, lateral strain difference method, crack strain method, energy dissipation rate method, and volumetric strain method, are compared to further verify the scientific nature of the new method. Finally, the method is applied to the conventional triaxial unloading confining pressure test and true triaxial loading and unloading test of marble, and the new method is fully extended to verify its universality.Results: The results show that the theoretical basis of the EGR characteristic stress determination method is rigorous and sufficient, and the value process is objective and reasonable. Compared with different methods, the EGR method can accurately define the process of rock asymptotic failure, and its corresponding characteristic stress level is well-consistent and in a reasonable range.Discussion: The EGR method is applicable to the conventional triaxial unloading confining pressure test and true triaxial loading and unloading test and has good universality.

To ensure the stability of an overlying roadway in close proximity to a 1000-m deep coal seam, this work, through theoretical analysis and numerical simulation, studies the deformation and failure mechanism, failure types, and prevention methods of the overlying roadway while mining a lower coal seam. Based on the study of mining conditions and overburdened space structures formed through mining, the deformation and failure law of the roadway in the strike and dip directions is obtained. Moreover, the stress evolution law of roadway deformation and failure is obtained by studying the influence of different mining stages and filling rates of the lower face on the mining of the overlying roadway. Results show that there are two types of potential roadway deformation and failure: (1) roadway section reduction failure and (2) roadway strike step subsidence failure. The fundamental cause of the deformation and failure of the overlying roadway is the influence of the large buried depth, strong mining stress, and unequal distance between the coal seam and roadway. The direct causes are the sudden increase in the stress of the roadway surrounding the rock and the subsidence of the key strata. In the mining process, when the mining range of the working face is more than 400 m, the roadway section reduction failure and strike ladder subsidence failure superimpose each other, inducing further roadway failure. Therefore, a scheme of partial filling and strengthening of the roadway along the working face is designed. Field measurements revealed that the above scheme can meet the stability requirements of the overlying roadway and the high efficiency and yield of the underlying working face. The results provide some references for the safe mining of coal in the 1000-m deep coal seam.

With the increase of mining depth, the gas management problem in coal and gas outburst mine is more prominent. At the same time, gas is used as a clean resource to mine together with coal which is to realize the simultaneous extraction of coal and gas more practical significance. The relation between coal mining and gas extraction is mutually reinforcing and restricting. It is of great theoretical significance and application value to study simultaneous extraction of coal and gas technique optimization. The Qidong Coal Mine of the Wanbei Coal and Electricity Group is a coal and gas outburst mine. The spacing of the coal seam is small, the occurrence conditions are complex, and the mining is difficult. This study used theoretical analysis, numerical simulation, and engineering analogy to investigate the coordinated mining technology of coal and gas in outburst coal seams. [ABSTRACT FROM AUTHOR]

Background: The exact mechanisms and targeted therapies for atopic dermatitis (AD), contact dermatitis (CD), and psoriasis (PS) remain unknown. Objectives: This study aimed to identify the biomarkers related to immune and novel therapeutic drugs for AD, CD, and PS. Methods: The GSE153007 dataset including 12 AD, 9 CD, and 14 PS samples and 40 control samples, which was obtained from the Gene Expression Omnibus database and analyzed. The immune infiltration level of each sample was then evaluated using the single-sample gene set enrichment analysis (ssGSEA). Then, we screened for immune-related differentially expressed genes (DEGs) that overlapped. The Database for Annotation, Visualization, and Integrated Discovery database was used to perform the gene ontology (GO) biological process. Furthermore, using search tool for the retrieval of interaction gene (STRING), the protein-protein interaction (PPI) was predicted on immune-related DEGs. We also searched the DGIdb database for novel therapeutic drugs for AD, CD, and PS. Results: According to ssGSEA results, most immune cells were highly infiltrated in the disease group. GO analysis indicated that AD, CD, and PS were enriched in signal transduction, inflammatory response, immune response, and innate immune response. We further found hub genes related to AD (CD4, ITGAM), CD (CD8A, CD86), and PS (CD4, CD8A) from PPI network. Moreover, the drug prediction indicated that drugs targeting CSF1R was the most effective for AD, whereas drugs targeting FCGR3A and CD86 were more effective for CD and PS. Conclusion: These immune-associated genes such as FCGR3A, CD86, and CSF1R might be regarded as therapeutic targets for patients with AD, CD, and PS.

The seeds of Vaccaria segetalis (Neck.) are from a traditional medicinal plant Garcke, also called Wang-Bu-Liu-Xing in China. According to the Chinese Pharmacopoeia, the seeds of V. segetalis can be used for treating urinary system diseases. This study was designed to investigate the underlying mechanism of VSP (polysaccharides from Vaccaria segetalis) against urinary tract infections caused by uropathogenic Escherichia coli (UPEC). Here, both in vitro and in vivo infection models were established with the UPEC strain CFT073. Bacterial adhesion and invasion into bladder epithelial cells were analyzed. We found that VSP reduced the adhesion of UPEC to the host by inhibiting the expression of bacterial hair follicle adhesion genes. VSP also reduced the invasion of UPEC by regulating the uroplakins and Toll-like receptors of host epithelial cells. In addition, the swarming motility and flagella-mediated motility genes flhC, flhD and Flic of UPEC were diminished after VSP intervention. Taken together, our findings reveal a possible mechanism by which VSP interferes with the adhesion and invasion of UPEC.

BACKGROUND Global harmonious high-quality geochemical data and accompanying maps are reference baselines for quantifying future human-induced or natural environmental changes. OBJECTIVES To ensure the accuracy of geochemical reference values and analysis data, advices were made for laboratory analysis. METHODS The analytical data of Cd, Hg and W from China, USA, Europe and Australia were compared and two analysis data collected 15 years apart from one laboratory in China were also compared. RESULTS All of the cadmium analysis data were consistent with a correlation coefficient of 0.96. Mercury was poorly consistent with a correlation coefficient of 0.74, and tungsten was not comparable with a correlation coefficient of 0.56. The analysis results of cadmium were highly consistent because the analysis method was the same and the detection limit was comparable. The consistency of mercury was poor, especially the low-content mercury, which was significantly different due to different analysis methods and detection limits. Tungsten was not comparable due to different laboratory analysis methods. The prerequisite for recognition of environmental changes (RCenv > REsmpl+RDlab) was that the change value must be larger than the value of field sampling error (REsmpl) and laboratory analysis error (RDlab). Therefore, sampling error and laboratory analysis error must be minimized. CONCLUSIONS Six general guidelines are proposed. (1) The original sample is separated through a 10-mesh sieve and processed to a particle size of less than 200 mesh using a pollution-free method. (2) A total of 71 elements plus other parameters should be determined by well-established multiple analysis methods, e.g., fused glass bead-XRF for major elements and 4-acids ICP-MS and ICP-OES for minor elements in combination with other methods. (3) The method detection limits must be lower than crustal abundance of the chemical elements and reportable data percentage must be more than 90%. (4) The geochemical reference materials used for quality control should contain the reported certified CRM values for all elements. (5) Analytical relative errors for the triplicate samples should be less than 40% (RD ≤ 40%) if concentration of the element is less than 3 times detection limits, and less than 20% (RD ≤ 20%) for the elements with concentration more than 3 times detection limits as well as major elements, Fe-group elements and toxic metals. (6) The total contents of major elements SiO2, Al2O3, Fe2O3, FeO, MnO, MgO, CaO, Na2O, K2O, TiO2, P2O5, H2O+, CO2, SO2 and organic matters or those of SiO2, Al2O3, Fe2O3, FeO, MnO, MgO, CaO, Na2O, K2O, TiO2, P2O5 and LOI should be at 99.3%-100.7%.

Abstract Background Haemonchus contortus, a blood-feeding parasite, is constantly surrounded by large quantities of heme released from the catabolism of host red blood cells. To cope with the toxicity of free heme, H. contortus needs to uptake and detoxify the heme, a process believed to be paramount for parasite survival. Methods A heme-responsive gene Hc-hrg-2 was identified which is the homologue of Ce-hrg-2. The transcriptional levels in all developmental stages and heme-responsive ability of Hc-hrg-2 were analyzed by qRT-PCR. Immunofluorescence analysis and cell transfections were performed to analyze the expression pattern of Hc-HGR-2. Statistical analyses were performed with GraghPad Prism 6.0 using Student’s t-test. Results To investigate the heme homeostasis of H. contortus, we first identified a heme-responsive gene Hc-hrg-2, a homolog of Ce-hrg-2 that is involved in heme transport in the hypodermis of Caenorhabditis elegans. Using qRT-PCR, we showed that Hc-hrg-2 mRNA was expressed throughout all life-cycle stages of H. contortus with the highest level in the third-stage larvae (L3s). Notably, transcription of Hc-hrg-2 in the exsheathed L3s was significantly upregulated in the presence of high concentration of heme. We found that Hc-HRG-2 protein was mainly located in the hypodermal tissues of adult H. contortus in vivo and the endoplasmic reticulum in the transfected mammalian cells. Our in vitro assay demonstrated that Hc-HRG-2 is a heme-binding protein with glutathione S-transferase activity and heme had a significant effect on its enzymatic activity when a model substrate 1-chloro-2, 4-dinitrobenzene (CDNB) was used. Conclusions Hc-hrg-2 is a heme-responsive gene and engaged in heme homeostasis regulation in hypodermal tissues during the free-living stages of H. contortus.

Hazardous weather has become a major cause of flight delays in recent years. With the development of satellite navigation systems, the study of flight-path optimization under hazardous weather conditions has become especially important. In this study, radar data were used as the basis for the initial flight-restricted area under hazardous weather conditions, and the Graham algorithm was used to delineate the dynamic flight-restricted area by comprehensively considering the hazardous weather boundary changes along with the speed and direction. Then, under the grid environment model, the range of influence, size, and distribution characteristics of the flight-restricted area was examined, and the path optimization model was created according to constraints related to the path distance, corner size, and number of turning points. An improved F-RRT∗ algorithm was developed to solve the model. The algorithm can overcome the problems of traditional path planning algorithms, such as strong randomness, poor guidance, slow convergence speed, unsmooth paths, and poor tracing smoothness. Finally, a simulation analysis was conducted on the Guiyang–Guangzhou route in China as an example. This study can address the drawbacks of existing research on route change and provide sufficient theoretical support and reference for the implementation of specific route change plans in the future.

An atmospheric window is greatly significant in the radiative cooling field. In this study, we preliminarily design a thermally tunable metamaterial emitter that can be used as an internal and external emission switch for a mid-infrared atmospheric window (3.5–5 and 8–14 μm). The proposed emitter has a multilayer metal–dielectric–metal micropyramid structure with thermochromic VO2 spacers. Its broadband emission and thermal tunability are due to the resonance of the hybridization of separate magnetic polaritons, surface plasmon polaritons, and the thermal phase-transition characteristics of VO2. The structure has a warming effect at the temperature below the phase-change temperature. On the contrary, it has a cooling effect at the temperature above the phase-change temperature. These phenomena show the emitter’s potential application in smart temperature control systems.

The geological conditions of coal mines in China are complicated. In recent years, with the continuous increase of intensity and depth of coal mining, coal and rock dynamic disasters are becoming more and more serious, and an important factor threatening the safety of coal mining. The accurate monitoring and early warning of coal and rock dynamic disasters are of great significance for disaster prevention. A large number of experiments conducted on both laboratory and field scales have demonstrated that the energy accumulated in rock material under loading can be released in the forms of acoustic emission (AE), electromagnetic radiation (EMR), etc. Therefore, AE and EMR, as the real-time, dynamic and continuous geophysical monitoring methods, have been widely used and played important roles in the field of monitoring and early-warning of coal and rock dynamic disasters in mines. To further study the time-frequency characteristics of AE and EMR and the relationships between these characteristics and load, and to provide the experimental basis for the monitoring and early warning of coal and rock dynamic disasters, an acoustic-electric full-waveform synchronous acquisition system of coal and rock fracture under loading was constructed in this paper. Using this system, the full-waveforms of AE and EMR of failure processes of coal samples under uniaxial compression were collected. The correlations among AE energy, EMR energy and load drop were studied, and the spectral characteristics of AE and EMR were analyzed. The results show that, (1) obvious acoustic-electric signals are emitted during the process of coal failure under loading. EMR is the paroxysmal signal, only accompanied by load drop and higher intensity AE. (2) Compared with AE, EMR has a higher correlation with load drop. There are high positive correlations among the cumulative values, relating to the cumulative released energy of coal fracture under loading, of AE energy, EMR energy and load drop. (3) The superiority frequency band of EMR is narrower than that of AE, with the former mainly concentrated in 1-25 kHz and the latter mainly in 1-280 kHz. Influenced by the initiation and propagation of the same crack, AE and EMR have similar low frequency components in the spectrum and main-frequency distribution.

Abstract Background Probiotic therapy can reduce the incidence of NEC. Therapeutic use of probiotics after NEC diagnosis reduces the severity of NEC in preterm infants or full-term infants is unclear. To evaluate the effect of probiotics on preventing the deterioration of necrotizing enterocolitis (NEC) from stage I to II/III. Methods A retrospective matched cohort study was performed. Included patients were ultimately divided into two groups: the probiotic treatment group (probiotics were used ≥4 days) and the no probiotic treatment group. The differences in deterioration trends between the two groups were compared. Additionally, the risk factors associated with the deterioration of NEC were further analyzed with a case-control study. Results A total of 231 infants met the inclusion criteria. Eighty-one pairs were matched according to similar gestational age and birth weight. Before matching, we found that the rate of deterioration of NEC from stage I to II/III in the group with probiotic treatment was similar to that in the group without probiotic treatment (23.1% [25/108] vs 26.0% [32/123], P = 0.614). After matching, the rate of deterioration of NEC between the two groups still had no significant difference (21.0% [17/81] vs 27.2% [22/81], P = 0.358). Logistic regression analysis showed that sepsis after NEC was an independent risk factor for NEC deteriorating from stage I to II/III (OR 2.378, 95% CI 1.005–5.628, P = 0.049). Conclusion Probiotics may not prevent the deterioration of NEC from stage I to II/III in infants, but this conclusion should be treated with caution.

ObjectiveThe aim of this study is the identification of hub genes associated with idiopathic pulmonary arterial hypertension (IPAH).Materials and MethodsGSE15197 gene expression data was downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified by screening IPAH patients and controls. The 5,000 genes with the greatest variances were analyzed using a weighted gene co-expression network analysis (WGCNA). Modules with the strongest correlation with IPAH were chosen, followed by a functional enrichment analysis. Protein–protein interaction (PPI) networks were constructed to identify hub gene candidates using calculated degrees. Real hub genes were found from the overlap of DEGs and candidate hub genes. microRNAs (miRNAs) targeting real hub genes were found by screening miRNet 2.0. The most important IPAH miRNAs were identified.ResultsThere were 4,395 DEGs identified. WGCNA indicated that green and brown modules associated most strongly with IPAH. Functional enrichment analysis showed that green and brown module genes were mainly involved in protein digestion and absorption and proteoglycans in cancer, respectively. The top ten candidate hub genes in green and brown modules were identified, respectively. After overlapping with DEGs, 11 real hub genes were identified: EP300, MMP2, CDH2, CDK2, GNG10, ALB, SMC2, DHX15, CUL3, BTBD1, and LTN1. These genes were expressed with significant differences in IPAH versus controls, indicating a high diagnostic ability. The miRNA–gene network showed that hsa-mir-1-3p could associate with IPAH.ConclusionEP300, MMP2, CDH2, CDK2, GNG10, ALB, SMC2, DHX15, CUL3, BTBD1, and LTN1 may play essential roles in IPAH. Predicted miRNA hsa-mir-1-3p could regulate gene expression in IPAH. Such hub genes may contribute to the pathology and progression in IPAH, providing potential diagnostic and therapeutic opportunities for IPAH patients.