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In order to solve the problem where the traditional intelligent inspection robot only has a single inspection function, we studied the use of a dry powder (including an ultra-fine dry powder) as a fire-extinguishing medium for the first time. In fire-extinguishing robots, the spray pressure is difficult to control, and there are several other issues. For integrated inspection, an intelligent, nitrogen-driven fire-extinguishing robot using a dry powder in a pressure-controlled spray was developed. On this basis, in order to investigate nitrogen-driven dry powder particle spraying as a gas–solid two-phase mechanism, as well as the flow characteristics and the influence of relevant parameters on the spraying effect, a nitrogen-driven dry powder particle spraying system was established as part of a gas–solid two-phase computational fluid dynamics model. The flow field of the spraying system and the particle motion characteristics were analyzed to explore the micro-mechanisms of the influence of different driving pressures, pipe diameters, and nozzle configurations on the spraying of the dry powder. In order to investigate the macroscopic effect of dry powder spraying where the gas–solid two-phase micro-mechanisms could not be revealed, an experimental platform was set up, and the experiments verified the accuracy of the numerical simulation results. We also investigated the dry powder spraying effect under different driving pressures, pipe diameters, nozzle configurations, and loading ratios. Finally, an orthogonal test was designed based on the results of the single-factor experiments to find the best combination of parameters required to achieve the optimal spraying effect. The research results can provide a theoretical and technical reference for the design and development of nitrogen-driven dry powder spraying systems. [ABSTRACT FROM AUTHOR]

Due to the particularity of raw materials and the complexity of processes, the petroleum and petrochemical industry involves a variety of disaster risks in production, transportation, storage and etc. However, there are three barriers in the emergency rescue of the petroleum and petrochemical industry, scene separation, data isolation and inefficient coordination. No matter the application of existing technology or the proposed method and concept, the situation cannot be broken quickly. By analyzing these problems existing in 5G communication technology, artificial intelligence and petroleum and petrochemical emergency rescue, this paper puts forward the concept of petroleum and petrochemical remote collaborative emergency technology, analyzes the development trend of remote collaborative emergency technology, and prospects the petroleum and petrochemical emergency rescue technology.

AB line and C line of Trans-Asia natural gas pipeline has attained a gas transmission capacity as 55 billion cubic meters per year. In recent years, pipeline transportation throughput accounts for about 20% of Chinese apparent consumption of natural gas. In order to ensure an economic and efficient operation of this transnational pipeline system, this paper conducts a comprehensive study on the joint operation of AB line and C line of Uzbekistan section of Trans-Asia natural gas pipeline. This paper innovatively puts forward “Methods of correction on multi-pressure head and multi-performance curve of centrifugal compressor”, aka. Data difference adjustment method”, to correct the factory performance curve of compressor, to ensure that the simulation accuracy is higher than 95%, and to provide support for operation decision-making. Based on the principle of minimum energy consumption of AB line and C line system of Trans-Asian natural gas pipeline, a set of optimal air intake allocation scheme between AB and C lines is studied and integration method of process operation scheme of AB line and C line are studied to support the optimum operation. Pipeline joint operation method for different hydraulic systems is studied. The pressure control principle by pressure balance method which realizes the joint operation of pipelines from different hydraulic systems is suggested for the first time, by which the pipeline operates stably. This paper studies the best location of 8 bridges reservations in AB line and C line in Uzbekistan, in order to enhance the comprehensively allocation capability of the whole system of transnational pipeline network in an all-round way, and to realize the function of energy conservation under normal conditions and of throughput guarantee under abnormal conditions. With additional bridges, pipeline transportation capacity can be increased up to 26 million m3/day and save energy consumption by up to 660 thousand m3/day under accident conditions. Keywords: Natural gas pipeline, Joint operation, Transmission allocation principle, Energy consumption

The article discusses a new suture method called the multi-gradient buried vertical mattress suture, which is used to close high-tension wounds. The method involves three buried vertical mattress sutures and an intradermal suture to reduce tension on wound edges and scar hyperplasia. However, the method does have the drawback of increased skin pigmentation and scarring at puncture points. The article provides a detailed description of the operative procedure and presents a typical case study to demonstrate the effectiveness of the suture method in reducing skin tension and improving aesthetic outcomes. [Extracted from the article]

To explore the influence of different wax components and the shear effect exerted by the pump and pipe wall in the process of crude oil pipeline transportation on the microbehavior of wax aggregation in crude oil at low temperatures, molecular dynamics models of binary and multivariate systems of crude oil with different wax components are established in this paper. The simulation results are compared with the existing experimental results and the NIST database to verify the rationality and accuracy of the models. By using the established binary model to simulate four crude oil systems containing different wax components, it can be found that the longer the wax molecular chain, the more easily the wax molecules aggregate. The influence of temperature on the aggregation process of wax molecules with different chain lengths is also studied. The lower the temperature, the greater the difference in wax molecular aggregation degree caused by the difference in molecular chain length. Nonequilibrium molecular dynamics is used to simulate the shear process of a multivariate system of crude oil, and the micromechanisms of the shear effect on the aggregation process of wax molecules are studied. Shearing can destroy the stable structure of crude oil, resulting in the orientation and conformational transformation of wax molecules, and obtaining the region of wax molecules sensitive to temperature and shear effects, the temperatures of which are below the wax precipitation point and the shear rate of which is lower than the maximum shear rate to prevent the molecular structure from being destroyed. At the same time, the sensitivity of wax components with different chain lengths to the shear effect is studied. The research results provide theoretical guidance for ensuring the safe and economic operation of waxy crude oil production. [ABSTRACT FROM AUTHOR]

In order to develop methods to further enhance oil recovery after water flooding in low permeability reservoirs by improving oil displacement efficiency, the displacement mechanism of residual oil was studied by the application of different pertinent measures. For in-depth investigation of oil displacement and variations in residual oil saturation, a large number of visual glass model displacement experiments were performed with different methods, such as changing the displacement direction, cyclic water flooding, displacement pressure difference variation and polymer flooding. In this paper, the models were divided into three (low, medium and high) permeability levels, and the residual oil after water flooding was categorized in five different types: cluster, oil film, oil drop, columnar and blind end residual oil. The experimental results showed that cluster residual oil accounted for the largest proportion after water flooding. In addition, with the increase in model permeability, cluster residual oil saturation increased and other types of residual oil saturations decreased. Compared to other methods, polymer flooding showed maximum displacement efficiency for the same displacement pressure and permeability model. The procedure was then followed by changing the displacement direction, cyclic water flooding and changing the displacement pressure difference. The different residual oil types can be activated by different methods, for example, cluster and columnar residual oil by changing the displacement direction, cluster and columnar residual oil by cyclic water flooding, cluster and oil drop residual oil by increasing displacement pressure difference. Moreover, all of the above mentioned five (05) types of residual oil can be activated by polymer flooding. [ABSTRACT FROM AUTHOR]

In this paper, wax deposition in waxy crude oil transportation process was regarded as an irreversible process. Based on the entropy production rate equations, the linear phenomenological equations for the diffusion of wax molecules were derived by using the theory and method of non-equilibrium thermodynamics and heat-mass transfer. Combined with the mass and energy conservation laws, the differential equations of heat and mass transfer in the process of pipeline transportation were established, and the molecular diffusion rate of dissolved wax was solved. On the basis of this, the mathematical model of actual wax deposition rate was established by considering the attachment process and scouring process of the wax molecules. Taking an oil pipeline in Daqing as an example, the change law and influencing factors of the wax molecular diffusion coefficient, the wax deposition rate, and the net wax deposition rate were studied by numerical simulation. The wax deposition rate test results of the laboratory loop test were compared with the theoretical calculation results in order to analyze the accuracy and the adaptability of heat and mass coupling mechanism and to provide a theoretical basis for further study of wax deposition in the process of waxy oil pipeline transportation. [ABSTRACT FROM AUTHOR]

Based on the phase equilibrium model of the paraffin wax precipitation in the process of oil pipeline transportation, theory and method of non-equilibrium thermodynamics were applied to obtain the linear phenomenological equations for the cross-interaction of heat and mass transfer during pipeline transport, which were derived from the irreversible entropy production rate equation. Then, the analysis of the irreversible heat flow and the mass flow were carried out, and the mathematical expressions of the phenomenological coefficient of liquid phase, the phenomenological coefficient of solid phase flow, and the heat flow phenomenological coefficient were obtained. Taking a waxy crude oil transportation pipeline in Daqing Oilfield as an example, based on the analysis of liquid–solid phase equilibrium, the irreversible linear phenomenological mechanism of heat and mass coupling in waxy crude oil pipeline transportation was analyzed in detail from three levels: phenomenological coefficients which reflect characteristic of the effect of force on flow in heat and mass transfer; thermodynamic forces which trigger heat and mass transfer; transmitted heat and mass flow density, providing a theoretical basis for the further study of the wax deposition in the process of pipeline transportation. [ABSTRACT FROM PUBLISHER]

Based on the technological requirements related to waxy crude oil pipeline transportation, both unavoidable and avoidable destroyed exergy are defined. Considering the changing characteristics of flow pattern and flow regime over the course of the oil transportation process, a method of dividing station oil pipelines into transportation intervals is suggested according to characteristic temperatures, such as the wax precipitation point and abnormal point. The critical transition temperature and the specific heat capacity of waxy crude oil are calculated, and an unavoidable destroyed exergy formula is derived. Then, taking the Daqing oil pipeline as an example, unavoidable destroyed exergy in various transportation intervals are calculated during the actual processes. Furthermore, the influential rules under various design and operation parameters are further analyzed. The maximum and minimum unavoidable destroyed exergy are 381.128 kJ/s and 30.259 kJ/s. When the design parameters are simulated, and the maximum unavoidable destroyed exergy is 625 kJ/s at the diameter about 250 mm. With the increase of insulation layer thickness, the unavoidable destroyed exergy decreases continuously, and the minimum unavoidable destroyed exergy is 22 kJ/s at 30 mm. And the burial depth has little effect on the unavoidable destroyed exergy. When the operation parameters are simulated, the destroyed exergy increases, but it is less affected by the outlet pressure. The increase amplitude of unavoidable destroyed exergy will not exceed 2% after the throughput rises to 80 m3/h. When the outlet temperature increases until 65 °C, the loss increase range will not exceed 4%. Thus, this study provides a theoretical basis for the safe and economical transportation of waxy crude oil. [ABSTRACT FROM AUTHOR]

Abstract Energy consumption plays a dominant role in the technical and economic indicators of pipeline operation, and is greatly influenced by operation schemes. However, the conventional energy consumption model is often analyzed from the perspective of "energy" in the process of optimization without addressing the issue of energy quality. Based on energy quality, this paper analyzes exergy loss and exergy efficiency of every component of the crude oil pipeline transportation system. The expression of the exergy loss is determined and the mathematical model of the pipeline transportation system is established with the optimization objective of minimizing the total exergy loss of the system, which is combined the two optimization algorithms of genetic algorithm and multi-objective programming. Using one external oil pipeline in northeast China as an example, the model is used to do hierarchical optimization for the equipment arrangement and operation parameters of each station in the pipeline transportation system. The results found that the total oil transportation cost and the total exergy loss of the pipeline transportation system after optimization have seen an obvious improvement in the effective utilization of energy when compared to pre-optimized levels. The purpose of reducing the operation energy consumption and exergy loss of the system as well as each subsystem simultaneously has been achieved, and the theoretical basis is provided for the energy consumption optimization of oil pipeline transportation system operations. [ABSTRACT FROM AUTHOR]

Challenges in assessing hepatitis B virus (HBV)-specific T cell immunity as an immunological biomarker still remain in chronic hepatitis B (CHB), such as the requirement of large quantities of cells. This study aims to conveniently assess HBV-specific T cells immunity in chronic HBV infected patients. We obtained T cell receptor β chains (TCRβs) from public databases and six acute hepatitis B patients to establish an HBV-specific TCRβs dataset. For some TCRs from one acute patient, their specificities and epitopes were verified. The potential HBV-specific TCRβs from CHB patients were analyzed using GLIPH2 and established dataset. By analyzing two antiviral therapy cohorts including 42 CHB patients, we showed that individuals with better therapy response may depend more on newly emerging potential HBV-specific TCRβs. In a cross-sectional study containing 207 chronic HBV infected patients, the results exhibited that the characteristics of potential HBV-specific clusters were divergent between CHB and hepatocellular carcinoma patients. Our strategy could profile potential HBV-specific TCRβ repertoire using a small blood sample, which will complement traditional methods for assessing the HBV-specific T cell immunity. • A strategy for profiling the potential HBV-specific TCRβ repertoire using a small blood sample. • Chronic hepatitis B patients with better response to therapy depend more on new TCR. • Different HBV-specific TCRβ clusters characteristics between patients with chronic hepatitis B and hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Background: Cisplatin (DDP) is a commonly used chemotherapy agent. However, its resistance to the drug is a major challenge in its clinical application. Earlier research has suggested a connection between HEATR1 and chemoresistance in cancer. However, additional investigation is needed to better understand its involvement in resistance to DDP. In this study, we aimed to determine the regulatory effect of HEATR1 on the resistance of cisplatin in NSCLC., Methods: We collected specimens of both DDP-resistant and non-resistant NSCLC to examine the expression of HEATR1. Additionally, we established cisplatin-resistant cells of NSCLC using the A549 cell line. Cell ability was examined by CCK-8 assay. Cell apoptosis and lipid ROS were examined by flow cytometry. The expressions of HEATR1, p53, SAT1, and ALOX15 were determined by qRT-PCR and Western blot. The tumor xenograft experiment was conducted to assess the impact of silencing HEATR1 on cisplatin resistance in vivo in NSCLC., Results: The expression levels of HEATR1 were found to be significantly elevated in DDP-resistant tissues and cells of NSCLC as compared to non-resistant counterparts. Conversely, the expression levels of p53, SAT1, and ALOX15 were observed to be reduced in DDP-resistant cells. Through the inhibition of HEATR1, the proliferation of DDP-resistant cells was significantly suppressed, while the generation of lipid ROS was enhanced. This effect was achieved by activating ferroptosis and the p53/SAT1/ALOX15 pathway, as demonstrated both in vitro and in vivo. Conversely, the overexpression of HEATR1 exhibited opposite effects. Furthermore, the silencing of p53 and ALOX15 reversed the oncogenic effects of HEATR1 and inhibited ferroptosis in DDP-resistant NSCLC cells, suggesting the involvement of p53 and ALOX15 in HEATR1-mediated DDP resistance., Conclusion: Finally, the findings revealed that HEATR1 silencing reduced DDP resistance in NSCLC by inducing ferroptosis via the p53/SAT1/ALOX15 axis. HEATR1 might become a potential target for overcoming DDP resistance in NSCLC treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Elderly individuals diagnosed with high-grade gliomas frequently experience unfavorable outcomes. We aimed to design two web-based instruments for prognosis to predict overall survival (OS) and cancer-specific survival (CSS), assisting clinical decision-making., Methods: We scrutinized data from the SEER database on 5,245 elderly patients diagnosed with high-grade glioma between 2000-2020, segmenting them into training (3,672) and validation (1,573) subsets. An additional external validation cohort was obtained from our institution. Prognostic determinants were pinpointed using Cox regression analyses, which facilitated the construction of the nomogram. The nomogram's predictive precision for OS and CSS was gauged using calibration and ROC curves, the C-index, and decision curve analysis (DCA). Based on risk scores, patients were stratified into high or low-risk categories, and survival disparities were explored., Results: Using multivariate Cox regression, we identified several prognostic factors for overall survival (OS) and cancer-specific survival (CSS) in elderly patients with high-grade gliomas, including age, tumor location, size, surgical technique, and therapies. Two digital nomograms were formulated anchored on these determinants. For OS, the C-index values in the training, internal, and external validation cohorts were 0.734, 0.729, and 0.701, respectively. We also derived AUC values for 3-, 6-, and 12-month periods. For CSS, the C-index values for the training and validation groups were 0.733 and 0.727, with analogous AUC metrics. The efficacy and clinical relevance of the nomograms were corroborated via ROC curves, calibration plots, and DCA for both cohorts., Conclusion: Our investigation pinpointed pivotal risk factors in elderly glioma patients, leading to the development of an instrumental prognostic nomogram for OS and CSS. This instrument offers invaluable insights to optimize treatment strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Jiang, Ren, Gu, Yao, Wang, Zou, Gan, Gu, Xu, Wang, Liu, Wang and Wei.)

Background: The tumor microenvironment in hepatocellular carcinoma (HCC) is complicated. Tumor-infiltrating T and B cells play a pivotal role in anti-tumor immunity. T cell receptor (TCR) and B cell receptor (BCR) features may reflect the disease-associated antigen response., Methods: By combining bulk TCR/BCR-sequencing, RNA-sequencing, whole exome-sequencing, and human leukocyte antigen-sequencing, we examined the immune repertoire (IR) features of tumor and adjacent non-tumor tissues obtained from 64 HCC patients., Results: High IR heterogeneity with weak similarity was discovered between tumor and non-tumor tissues. Higher BCR diversity, richness, and somatic hypermutation (SHM) were found in non-tumor tissues, while TCRα and TCRβ diversity and richness were comparable or higher in tumor. Additionally, lower immune infiltration was found in tumor than non-tumor tissues; the microenvironment in tumor appeared to keep stably inhibited and changed slightly with tumor progression. Moreover, BCR SHM was stronger, whereas TCR/BCR diversity declined with HCC progression. Importantly, we found that higher IR evenness in tumor and lower TCR richness in non-tumor tissues indicated better survival in HCC patients. Collectively, the results revealed that TCR and BCR exhibited distinct features in tumor and non-tumor tissues., Conclusions: We demonstrated that IR features vary between different tissues of HCC. IR features may represent a biomarker for the diagnosis and treatment of HCC patients, providing references for subsequent immunotherapy research and strategy selection., Competing Interests: Author LT was employed by HRYZ Biotech Co., Shenzhen, China. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Xie, Yan, Zheng, Shi, Tang, Li, Liu, Gan, Wang, Jiang, Liu, Wu and Wang.)

Introduction: The most important chemotherapy treatment for glioma patients is temozolomide. However, the development of drug resistance severely restricts the use of temozolomide. Therefore, elucidating the mechanism of temozolomide resistance, enhancing temozolomide sensitivity, and extending patient survival are urgent tasks for researchers., Methods: Temozolomide resistance hub differential genes were identified using differential analysis and protein interaction analysis from the GEO datasets (GSE100736 and GSE113510). These genes were further studied in glioma patients treated with temozolomide in the TCGA and CGGA databases. Patients from the mRNAseq_325 dataset (CGGA) were considered as the training set to construct a risk model for predicting glioma sensitivity to temozolomide, while patients from the mRNAseq_693 dataset (CGGA) and TCGA-GBM dataset were considered as the validation set to evaluate the performance of models. PCR and western blot were performed to determine the difference in expression of the feature gene DACH1 between glioma cells and temozolomide-resistant glioma cells. The alterations in the sensitivity of tumor cells to temozolomide were also observed after DACH1 was silenced. The patients were then divided into two groups based on the expression of DACH1, and the differences in patient survival rates, molecular pathway activation, and level of immune infiltration were compared., Results: Based on four signature genes (AHR, DACH1, MGMT, and YAP1), a risk model for predicting glioma sensitivity to temozolomide was constructed, and the results of timeROC in both the training and validation sets showed that the model had good predictive performance. The expression of the signature gene DACH1 was significantly downregulated in temozolomide-resistant cells, according to the results of the PCR and western blot experiments. The sensitivity of tumor cells to temozolomide was significantly reduced after DACH1 was silenced. DACH1 probably regulates temozolomide resistance in glioblastoma through the transcriptional dysregulation in cancer and ECM., Discussion: This study constructs a risk model that can predict glioma susceptibility to temozolomide and validates the function of the feature gene DACH1, which provides a promising target for the research of temozolomide resistance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Gu, Li, Yao, Dong, Gan, Zhou, Wang and Wang.)