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1.
Sci Rep ; 14(1): 8110, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582944

RESUMO

In view of the problem of poor coupling adaptability and easy rib spalling of coal wall in large mining height comprehensive mining, based on the effective inhibition effect of face guard mechanism on coal wall spalling, the structural characteristics and bearing capacity of different structural forms of the face guard mechanism are compared and analyzed. According to the surrounding rock adaptability of the face guard mechanism, established a numerical analysis model for rigid-flexible coupling of the face guard mechanism under different spalling forms. In order to accurately simulate the stress state of the protective mechanism, a variable stiffness spring damping system is used to replace the hydraulic cylinder. The load-bearing performance and response characteristics of the face guard mechanism under rib spalling coupling conditions were analyzed by applying uniform normal load and impact load to the face guard. The findings indicated that, the integral-type face guard mechanism has a better effect on suppressing rib spalling. When the face guard mechanism bears the static load of the coal wall, the entire response process of the face guard jack can be divided into three stages: initial support, increasing resistance bearing, constant resistance bearing; both the impact load position and the coupling state of the rib spalling will affect the characteristics of force transmission at the face guard mechanism's hinge point, the hinge point between the extensible canopy and the primary face guard is most sensitive to biased load. The research results can provide reference for optimizing the face guard mechanism of large mining height hydraulic support and improving the reliability of coal wall support.

2.
Molecules ; 28(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37630210

RESUMO

The interface models of diamond-coated WC-Co cemented carbide (DCCC) were constructed without intermediate layers and with different interface terminals, such as intermediate layers of TiC, TiN, CrN, and SiC. The adhesion work of the interface model was calculated based on the first principle. The results show that the adhesion work of the interface was increased after adding four intermediate layers. Their effect on improving the interface adhesion performance of cemented carbide coated with diamond was ranked in descending order as follows: SiC > CrN > TiC > TiN. The charge density difference and the density of states were further analyzed. After adding the intermediate layer, the charge distribution at the interface junction was changed, and the electron cloud at the interface junction overlapped to form a more stable chemical bond. Additionally, after adding the intermediate layer, the density of states of the atoms at the interface increased in the energy overlapping area. The formant formed between the electronic orbitals enhances the bond strength. Thus, the interface bonding performance of DCCC was enhanced. Among them, the most obvious was the interatomic electron cloud overlapping at the diamond/SiCC-Si/WC-Co interface, its bond length was the shortest (1.62 Å), the energy region forming the resonance peak was the largest (-5-20 eV), and the bonding was the strongest. The interatomic bond length at the diamond/TiNTi/WC-Co interface was the longest (4.11 Å), the energy region forming the resonance peak was the smallest (-5-16 eV), and the bonding was the weakest. Comprehensively considering four kinds of intermediate layers, the best intermediate layer for improving the interface bonding performance of DCCC was SiC, and the worst was TiN.

3.
Molecules ; 28(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37110818

RESUMO

This study performed first-principle-based calculations of the interface adhesion work in interface models of three terminal systems: CrAlSiNSi/WC-Co, CrAlSiNN/WC-Co, and CrAlSiNAl/WC-Co. The results proved that the CrAlSiNSi/WC-Co and CrAlSiNAl/WC-Co interface models had the highest and lowest interface adhesion work values (4.312 and 2.536 J·m-2), respectively. Thus, the latter model had the weakest interface bonding property. On this basis, rare earth oxides CeO2 and Y2O3 were doped into the Al terminal model (CrAlSiNAl/WC-Co). Then, doping models of CeO2 and Y2O3 doped on the WC/WC, WC/Co, and CrAlSiNAl/WC-Co interfaces were established. The adhesion work value was calculated for the interfaces in each doping model. When CeO2 and Y2O3 were doped in the WC/WC and CrAlSiNAl/WC-Co interfaces, four doping models were constructed, each model contains interfaces withreduced adhesion work values, indicating deteriorated interface bonding properties. When the WC/Co interface was doped with CeO2 and Y2O3, the interface adhesion work values of the two doping models are both increased, and Y2O3 doping improved the bonding properties of the Al terminal model (CrAlSiNAl/WC-Co) more significantly than CeO2 doping. Next, the charge density difference and the average Mulliken bond population were estimated. The WC/WC and CrAlSiNAl/WC-Co interfaces doped with CeO2 or Y2O3, with decreased adhesion work, exhibited low electron cloud superposition and reduced values of charge transfer, average bond population, and interatomic interaction. When the WC/Co interface was doped with CeO2 or Y2O3, superposition of the atomic charge densities of electron clouds was consistently observed at the CrAlSiNAl/WC-Co interface in the CrAlSiNAl/WC/CeO2/Co and CrAlSiNAl/WC/Y2O3/Co models; the atomic interactions were strong, and the interface bonding strength increased. When the WC/Co interface was doped with Y2O3, the superposition of atomic charge densities and the atomic interactions were stronger than for CeO2 doping. In addition, the average Mulliken bond population and the atomic stability were also higher, and the doping effect was better.

4.
Micromachines (Basel) ; 14(2)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36838131

RESUMO

Based on the first-principles method, TiAlSiN/WC-Co interface models with graphene doped into the matrix, coating, and the coating/matrix are constructed. The interface adhesion work is calculated and modeled to study the interface bonding properties from the atomic microscopic point of view. The results show that the interface bonding properties of TiAlSiN/WC-Co can be improved when the matrix is doped with the main surface of intrinsic graphene, and the interface bonding property of TiAlSiNN/WC-Co can be improved when the coating and coating/matrix are doped separately with the main surface of intrinsic graphene or single vacancy defective graphene. Furthermore, the model electronic structures are analyzed. The results show that there exist strong Si/Co and N/Co covalent bonds in the interfaces when the matrix is doped with the main surface of intrinsic graphene, which causes the adhesion work of TiAlSiN/WC/msGR/Co to be greater than that of TiAlSiN/WC-Co. Additionally, when the graphene is doped into the coating, in the interface of TiAlSiN/msGR/TiAlSiNN/WC-Co, there exist strong N/Co covalent bonds that increase the interface adhesion work. Additionally, more charge transfer and orbital hybridization exist in the coating/matrix interface doped with the main surface of intrinsic graphene or single vacancy defective graphene, which explains the essential mechanism that the adhesion work of TiAlSiNN/msGR/WC-Co is greater than that of TiAlSiNN/WC-Co, and the adhesion work of TiAlSiNN/svGR/WC-Co is greater than that of TiAlSiNN/WC-Co.

5.
Biomed Res Int ; 2022: 4541571, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795311

RESUMO

ZC3H12C is an important member of the CCCH-zinc finger protein family and is mainly involved in host immune and inflammatory diseases. However, its abnormal expression and prognostic value in cancer have not yet been established. Through comparative analysis of the Cancer Genome Atlas (TCGA) database, we found that ZC3H12C is the most relevant to the prognosis, grade, and stage of renal clear cell carcinoma (ccRCC) across 33 cancers. With the help of patient transcription and clinical data from the TCGA and GEO (GSE53757, GSE36895) databases, we determined that in the immune environment of patients with ccRCC, ZC3H12C was clearly negatively correlated with Tregs and was significantly positively correlated with monocytes. In addition, protein phosphorylation and DNA methylation analysis also showed that ZC3H12C negatively regulates the role of cancer in ccRCC. Our research may provide new insights into ccRCC immunotherapy and bring forth novel biomarkers and therapeutic targets.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/patologia , Humanos , Neoplasias Renais/patologia , Prognóstico
6.
Med Sci Monit ; 28: e937005, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35726168

RESUMO

BACKGROUND The Integrated Liver Inflammatory Score (ILIS), which includes 5 serum indicators (albumin, bilirubin, neutrophil count, alpha-fetoprotein [AFP], and alkaline phosphatase [ALP]), is a novel inflammation-based predictive model associated with poor survival in hepatocellular carcinoma (HCC) patients. Our study aimed to assess the prognostic value of ILIS in HCC patients undergoing radical hepatectomy and establish a nomogram and artificial neural network based on their ILIS scores. MATERIAL AND METHODS This multicenter retrospective study included patients from 2 institutions from 2007 to 2017. Independent risk factors associated with Recurrence-free survival (RFS) and overall survival (OS) were identified through univariate and multifactor analysis in the training and validation groups, respectively. Afterward, column line graphs and artificial neural networks (ANN) were constructed and validated using the validation group. RESULTS A total of 432 patients were included in this study (275 in the training group and 157 in the validation group). In both cohorts, ILIS was correlated with pathological features such as tumor size, degree of differentiation, Child-Pugh class classification, and BCLC staging. Moreover, ILIS was identified as an independent risk factor for OS. ILIS-based nomograms and artificial neural networks also showed the prognostic value of ILIS. CONCLUSIONS Preoperative ILIS is an independent and effective predictor of prognosis in HCC patients treated with radical hepatectomy, as shown by the fact that higher ILIS are associated with worse patient prognosis. We have also established nomograms and ANNs that predict HCC prognosis with high accuracy.


Assuntos
Carcinoma Hepatocelular , Hepatite , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Hepatectomia/métodos , Humanos , Neoplasias Hepáticas/patologia , Prognóstico , Estudos Retrospectivos
7.
Front Cell Dev Biol ; 9: 802745, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34966746

RESUMO

Gastric cancer (GC) is one of the most common malignancies in the world. It is also the fifth most common cancer in China. In recent years, a large number of studies have proved that non-coding RNAs (ncRNAs) can regulate cell proliferation, invasion, metastasis, apoptosis, and angiogenesis. NcRNAs also influence the therapeutic resistance of gastric cancer. NcRNAs mainly consist of miRNAs, lncRNAs and circRNAs. In this paper, we summarized ncRNAs as biomarkers and therapeutic targets for gastric cancer, and also reviewed their role in clinical trials and diagnosis. We sum up different ncRNAs and related moleculars and signaling pathway in gastric cancer, like Bcl-2, PTEN, Wnt signaling. In addition, the potential clinical application of ncRNAs in overcoming chemotherapy and radiotherapy resistance in GC in the future were also focused on.

8.
Biomed Res Int ; 2021: 7405322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34676262

RESUMO

Several studies have suggested that coatomer protein complex subunit beta 2 (COPB2) may act as an oncogene in various cancer types. However, no systematic pan-cancer analysis has been performed to date. Therefore, the present study analyzed the potential oncogenic role of COPB2 using TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus) datasets. The majority of the cancer types overexpressed the COPB2 protein, and its expression significantly correlated with tumor prognosis. In certain tumors, such as those found in breast and ovarian tissues, phosphorylated S859 exhibited high expression. It was found that mutations of the COPB2 protein in kidney and endometrial cancers exhibited a significant impact on patient prognosis. It is interesting to note that COPB2 expression correlated with the number of cancer-associated fibroblasts in certain tumors, such as cervical and endocervical cancers and colon adenocarcinomas. In addition, COPB2 was involved in the transport of substances and correlated with chemotherapy sensitivity. This is considered the first pan-tumor study, which provided a relatively comprehensive understanding of the mechanism by which COPB2 promotes cancer growth.


Assuntos
Proteína Coatomer/genética , Terapia de Alvo Molecular/métodos , Neoplasias/genética , Proteína Coatomer/metabolismo , Biologia Computacional , Bases de Dados Genéticas , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Prognóstico , Taxa de Sobrevida
9.
Biomed Res Int ; 2021: 8201377, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616846

RESUMO

METHODS: The expression level of GRWD1 in human cancer tissues was analyzed using the Tumor Immune Evaluation Resource (ver. 2.0, TIMER2), Gene Expression Profiling Interactive Analysis (ver. 2, GEPIA2), and UALCAN databases. The Kaplan-Meier plotter was utilized to analyze the survival data. Spearman's correlation analysis was used to find out the correlation between the expression level of GRWD1 and predictive biomarkers, such as tumor mutation burden (TMB) and microsatellite instability (MSI). Furthermore, the MEXPRESS website was used to study the potential relationship between DNA methylation level of GRWD1 and pathological staging. We utilized the "immune" module provided on the TIMER2 website to explore the relationship between the expression level of GRWD1 and immune infiltration in all types of cancer in TCGA. Pearson's correlation analysis was used to investigate the correlation between the expression level of GRWD1 and the expression levels of immune checkpoint-related genes. For protein expression analysis, we used the CPTAC module provided by the UALCAN portal to compare the total protein and phosphorylated protein level of GRWD1 in adjacent normal and tumor tissues. RESULTS: GRWD1 was overexpressed in tissues of most types of cancer, in which the expression levels of GRWD1 in the kidney chromophobe (KICH), kidney renal papillary cell carcinoma (KIRP), and kidney renal clear cell carcinoma (KIRC) tissues showed an opposite trend, and the expression level of GRWD1 was correlated to only the KIRC tumor stage. The results of survival analysis showed that the expression level of GRWD1 was significantly associated with overall survival in six types of cancer and disease-free survival (DFS) in three types of cancer. Importantly, the increased expression level of GRWD1 was strongly correlated with prognosis of KIRC patients. There was a positive relationship between the expression level of GRWD1 and immune cell infiltration in several types of cancer, and the expression level of GRWD1 was also positively correlated with TMB, MSI, and DNA methylation in some types of cancer. The results of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that "ubiquitin mediated proteolysis," "spliceosome," and "nucleotide excision repair" were involved in the effect of GRWD1 expression on tumor pathogenesis. CONCLUSION: This pancancer analysis provided a comprehensive overview of the carcinogenic effects of GRWD1 on a variety of human cancers. The results of bioinformatics analysis indicated GRWD1 as a promising biomarker for detection, prognosis, and therapeutic assessment of diverse types of cancer, and GRWD1 could act as a tumor suppressor in KIRC.


Assuntos
Proteínas de Transporte/genética , Ácido Glutâmico/metabolismo , Neoplasias/genética , Repetições WD40/genética , Proteínas de Transporte/metabolismo , Metilação de DNA/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/imunologia , Neoplasias/patologia , Fosforilação , Mapas de Interação de Proteínas/genética , Análise de Sobrevida
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