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Article ; Online: Simulation of the interactions between multiple hydraulic fractures and natural fracture network based on Discrete Element Method numerical modeling

Yumei Li

Energy Science & Engineering, Vol 8, Iss 8, Pp 2922-

2020 Volume 2937

Abstract: Abstract Obtaining the most Stimulated Reservoir Volume (SRV) by forming a complex fracture network is the prerequisite for shale gas hydraulic fracturing. In this paper, a coupled DFN–DEM model is presented based on a realistic discrete fracture network ...

Abstract	Abstract Obtaining the most Stimulated Reservoir Volume (SRV) by forming a complex fracture network is the prerequisite for shale gas hydraulic fracturing. In this paper, a coupled DFN–DEM model is presented based on a realistic discrete fracture network from fracturing treatment, to simulate the complex interactions between a created hydraulic fracture and a natural fracture system in shale. The sensitivity analysis of numerical simulation was performed to investigate the effects of hydraulic fracture length, multi‐fracture spacing, and internal friction angle on the stimulation reservoir area. The simulation results revealed that regardless of the DFN distribution and the length of hydraulic fracture, shear failure always tracked on the existing natural fracture plane. The amount and depth of the natural fracture shear into formation increased as the hydraulic fracture grew in length. Moreover, the actual dynamic morphology of fracture network was the radial or dendritic. A drastic change of permeability along the distance from injection may stimulate the fracture networks especially near the wellbore. For the multi‐fracture, the opening of the second fracture was able to stabilize the sheared fractures at the tip of the initial fracture. The shear failure area around the second fracture tended to increase with the growth of the length of the second fracture. Fracture network connectivity in the system is better for the optimal fracture spacing, and then fluid penetration during injection will influence the permeability evolution during stimulation. The stimulation reservoir area of the fracture network and the natural fracture friction angle had a quadratic relationship. Finally, the results by the data from field measurement in Sichuan, China verified that the proposed coupled DFN–DEM model had an accuracy up to 91.7%. The research results provide a reference for predicting the development of fracture network far away for multistage fracturing treatment.
Keywords	DEM ; DFN ; hydraulic fracture ; natural fracture ; stimulation reservoir area ; Technology ; T ; Science ; Q
Subject code	550
Language	English
Publishing date	2020-08-01T00:00:00Z
Publisher	Wiley
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Influence of the Kinship Networks on Farmers’ Willingness to Revitalize Idle Houses

Yao Luo / Yumei Li / Chen Li / Qun Wu

Sustainability, Vol 15, Iss 10285, p

2023 Volume 10285

Abstract: China is vigorously promoting the strategy of rural revitalization, encouraging farmers to revitalize their idle houses and developing rural tourism. In rural China, kinship networks are essential in farmers’ willingness and decision–making tools. It is ... ...

Abstract	China is vigorously promoting the strategy of rural revitalization, encouraging farmers to revitalize their idle houses and developing rural tourism. In rural China, kinship networks are essential in farmers’ willingness and decision–making tools. It is significant to explore the influence of kinship networks on farmers’ willingness to revitalize idle houses. This study constructs a research framework of “kinship networks–revitalization willingness–revitalization action”. It describes farmers’ kinship networks from five aspects: kinship networks structure, kinship networks relationship, kinship networks cognition, kinship networks members’ sense of belonging, and their social participation enthusiasm. Taking Bishan Village, a typical rural tourism–type ancient village, as an example, this study surveyed 197 farmers to demonstrate the influence of kinship networks on farmers willingness to revitalize idle houses. This paper uses a multiple regression model to empirically study the influence of kinship networks on farmers’ willingness to revitalize idle houses. The results show that: (1) In addition to the kinship networks structure having no significant positive impact on farmers’ willingness to revitalize idle houses, kinship networks relationship, kinship networks cognition, kinship networks members’ sense of belonging, and kinship networks members’ social participation enthusiasm all have positive effects on farmers’ willingness. (2) Considering the critical influence of kinship networks on farmers’ willingness to revitalize idle houses, the government should use the structure of kinship networks to formulate relevant policies to guide farmers to increase their willingness to revitalize their idle houses.
Keywords	kinship networks ; revitalize idle houses ; farmers’ willingness ; rural revitalization ; Bishan Village ; Environmental effects of industries and plants ; TD194-195 ; Renewable energy sources ; TJ807-830 ; Environmental sciences ; GE1-350
Subject code	650
Language	English
Publishing date	2023-06-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Terpinen-4-ol Induces Ferroptosis of Glioma Cells via Downregulating JUN Proto-Oncogene

Wenpeng Cao / Yumei Li / Zhirui Zeng / Shan Lei

Molecules, Vol 28, Iss 4643, p

2023 Volume 4643

Abstract: According to previous research, turmeric seeds exhibit anti-inflammatory, anti-malignancy, and anti-aging properties due to an abundance of terpinen-4-ol (T4O). Although it is still unclear how T4O works on glioma cells, limited data exist regarding its ... ...

Abstract	According to previous research, turmeric seeds exhibit anti-inflammatory, anti-malignancy, and anti-aging properties due to an abundance of terpinen-4-ol (T4O). Although it is still unclear how T4O works on glioma cells, limited data exist regarding its specific effects. In order to determine whether or not glioma cell lines U251, U87, and LN229 are viable, CCK8 was used as an assay and a colony formation assay was performed using different concentrations of T4O (0, 1, 2, and 4 μM). The effect of T4O on the proliferation of glioma cell line U251 was detected through the subcutaneous implantation of the tumor model. Through high-throughput sequencing, a bioinformatic analysis, and real-time quantitative polymerase chain reactions, we identified the key signaling pathways and targets of T4O. Finally, for the measurement of the cellular ferroptosis levels, we examined the relationship between T4O, ferroptosis, and JUN and the malignant biological properties of glioma cells. T4O significantly inhibited glioma cell growth and colony formation and induced ferroptosis in the glioma cells. T4O inhibited the subcutaneous tumor proliferation of the glioma cells in vivo. T4O suppressed JUN transcription and significantly reduced its expression in the glioma cells. The T4O treatment inhibited GPX4 transcription through JUN. The overexpression of JUN suppressed ferroptosis in the cells rescued through T4O treatment. Taken together, our data suggest that the natural product T4O exerts its anti-cancer effects by inducing JUN/GPX4-dependent ferroptosis and inhibiting cell proliferation, and T4O will hope-fully serve as a prospective compound for glioma treatment.
Keywords	terpinen-4-ol ; glioma ; ferroptosis ; proliferation ; JUN ; Organic chemistry ; QD241-441
Subject code	570
Language	English
Publishing date	2023-06-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Identification of Core Genes and Pathways in Melanoma Metastasis via Bioinformatics Analysis

Renjian Xie / Bifei Li / Lee Jia / Yumei Li

International Journal of Molecular Sciences, Vol 23, Iss 794, p

2022 Volume 794

Abstract: Metastasis is the leading cause of melanoma-related mortality. Current therapies are rarely curative for metastatic melanoma, revealing the urgent need to identify more effective preventive and therapeutic targets. This study aimed to screen the core ... ...

Abstract	Metastasis is the leading cause of melanoma-related mortality. Current therapies are rarely curative for metastatic melanoma, revealing the urgent need to identify more effective preventive and therapeutic targets. This study aimed to screen the core genes and molecular mechanisms related to melanoma metastasis. A gene expression profile, GSE8401, including 31 primary melanoma and 52 metastatic melanoma clinical samples, was downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) between melanoma metastases and primary melanoma were screened using GEO2R tool. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) analyses of DEGs were performed using the Database for Annotation Visualization and Integrated Discovery (DAVID). The Search Tool for the Retrieval of Interacting Genes (STRING) and Cytoscape with Molecular Complex Detection (MCODE) plug-in tools were utilized to detect the protein–protein interaction (PPI) network among DEGs. The top 10 genes with the highest degrees of the PPI network were defined as hub genes. In the results, 425 DEGs, including 60 upregulated genes and 365 downregulated genes, were identified. The upregulated genes were enriched in ECM–receptor interactions and the regulation of actin cytoskeleton, while 365 downregulated genes were enriched in amoebiasis, melanogenesis, and ECM–receptor interactions. The defined hub genes included CDK1 , COL17A1 , EGFR , DSG1 , KRT14 , FLG , CDH1 , DSP , IVL , and KRT5 . In addition, the mRNA and protein levels of the hub genes during melanoma metastasis were verified in the TCGA database and paired post- and premetastatic melanoma cells, respectively. Finally, KRT5 -specific siRNAs were utilized to reduce the KRT5 expression in melanoma A375 cells. An MTT assay and a colony formation assay showed that KRT5 knockdown significantly promoted the proliferation of A375 cells. A Transwell assay further suggested that KRT5 knockdown significantly increased the cell migration and cell invasion of ...
Keywords	melanoma metastasis ; bioinformatics analysis ; differentially expressed genes ; hub gene ; KRT5 ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
Subject code	570
Language	English
Publishing date	2022-01-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Security-Enhanced Certificate-Based Remote Data Integrity Batch Auditing for Cloud-IoT

Wenhao Wang / Yinxia Sun / Yumei Li

Security and Communication Networks, Vol

2022 Volume 2022

Abstract: The Internet of Things (IoT) plays a crucial role in the generation of new, intelligent information technologies. Generally, the IoT facilities are composed of lightweight devices, and they expand computing and storage resources primarily through the ... ...

Abstract	The Internet of Things (IoT) plays a crucial role in the generation of new, intelligent information technologies. Generally, the IoT facilities are composed of lightweight devices, and they expand computing and storage resources primarily through the cloud. Massive data collected by intelligent devices will be stored in cloud servers, but the vulnerabilities of cloud servers will directly threaten the security and reliability of the IoT. To ensure the integrity of data in the cloud, data owners need to audit the integrity of their outsourced data. Recently, several remote data integrity batch auditing protocols have been proposed to reduce transmission loss and time cost in the auditing process. However, most of them cannot resist collusion attacks. Meanwhile, certificate management problem exists in their system, which brings an enormous burden on the system. In this paper, we construct a certificate-based remote data integrity batch auditing protocol which can issue batch auditing and resist the highest level of collusion attacks—the fully chosen-key attacks for cloud-IoT . Our protocol makes use of a certificate-based cryptosystem which gets rid of the certificate management problem and key escrow problem, with no need for secret channels. Our protocol is proved to be secure in the random oracle model and implemented to show its efficiency. The simulation results illustrate that, in the case of enhanced security, our batch auditing protocol still has computational efficiency and practicability.
Keywords	Technology (General) ; T1-995 ; Science (General) ; Q1-390
Subject code	006
Language	English
Publishing date	2022-01-01T00:00:00Z
Publisher	Hindawi-Wiley
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Pancancer Analysis of the Oncogenic and Prognostic Role of NOL7

Qiaojun Liu / Renjian Xie / Yumei Li

International Journal of Molecular Sciences, Vol 23, Iss 9611, p

A Potential Target for Carcinogenesis and Survival

2022 Volume 9611

Abstract: Despite growing evidence suggesting the critical function of NOL7 in cancer initiation and development, a systematic pancancer analysis of NOL7 is lacking. Herein, we present a comprehensive study of NOL7 which aimed to explore its potential role and ... ...

Abstract	Despite growing evidence suggesting the critical function of NOL7 in cancer initiation and development, a systematic pancancer analysis of NOL7 is lacking. Herein, we present a comprehensive study of NOL7 which aimed to explore its potential role and detailed mechanisms across 33 human tumors based on The Cancer Genome Atlas (TCGA) and Clinical Proteomic Tumor Analysis Consortium (CATPAC) databases. As a result, both gene and protein levels of NOL7 were found to be increased in various tumor tissues, including breast invasive carcinoma (BRCA), colon adenocarcinoma (COAD), hepatocellular carcinoma (LIHC), lung adenocarcinoma (LUAD), and head and neck squamous cell carcinoma (HNSC) as compared with corresponding normal tissues. Meanwhile, dysregulated NOL7 expression was found to be closely related to pathological stage and prognosis in several cancers, including LIHC, ovarian serous cystadenocarcinoma (OV), and bladder urothelial carcinoma (BLCA). The DNA methylation level of NOL7 was found to be decreased in most cancers and to be negatively associated with NOL7 expression. Furthermore, NOL7 expression was determined to be significantly associated with levels of infiltrating cells and immune checkpoint genes, including HMGB1 . Analysis of NOL7 -related genes revealed that RNA metabolism pathways, including “ribosome biogenesis”, “spliceosome”, and “RNA transport”, were mainly involved in the functional mechanism of NOL7 in human cancers. In summary, this pancancer study characterized the relationship between NOL7 expression and clinicopathologic features in multiple cancer types and further showed its potential regulatory network in human cancers. It represents a systemic analysis for further functional and therapeutic studies of NOL7 and highlights its predictive value with respect to the carcinogenesis and prognosis of various cancers, especially LIHC.
Keywords	NOL7 ; pancancer ; oncogenesis ; prognosis ; human tumor ; enrichment analysis ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
Subject code	616
Language	English
Publishing date	2022-08-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Investigation of the factors affecting the self‐propelled force in a multi‐orifice nozzle using a novel simulation method

Yumei Li / Tao Zhang

Energy Science & Engineering, Vol 8, Iss 9, Pp 3136-

2020 Volume 3147

Abstract: Abstract A multi‐orifice nozzle is the primary actuator of radial jet drilling for the stimulation of unconventional and low‐permeability reservoirs. This research developed a 3D flow field simulation model to investigate the self‐propelled force of a ... ...

Abstract	Abstract A multi‐orifice nozzle is the primary actuator of radial jet drilling for the stimulation of unconventional and low‐permeability reservoirs. This research developed a 3D flow field simulation model to investigate the self‐propelled force of a multi‐orifice nozzle based on ANSYS‐CFX. To evaluate the self‐propelled ability of the nozzle, investigation was performed on the effects of the angle, number, the diameter of the forward and backward orifices of the multi‐orifice nozzle, and the diameter of the micro‐hole in the radial well on its self‐propelled ability by sensitivity analysis. The results revealed that the self‐propelled force slightly increased with the angle of forward orifice increasing, and decreased with the angle of backward orifice increasing; and that the self‐propelled force had a tendency to decrease significantly with the number of forward orifices increasing, and increased slightly with the number of backward orifices increasing. The self‐propelled forces for different combinations of forward and backward orifices were obtained by the simulation method, which agreed well with those obtained by the calculation method, with an average accuracy of 95.82%. It was observed that the self‐propelled force increased substantially as the value of K (d2/d1) increased, but tended to slow down when the flow rate was within a certain range. Besides, with the increase in the diameter of the micro‐hole, the self‐propelled force reduced, and increased substantially as the inlet flow rate increased, but tended to slow down as the inlet flow rate further increased. Thus, to ensure the self‐propelled ability of the jet nozzle, a set of optimal structural parameters can be used to generate the target self‐propelled ability. The research improves the working performance of multi‐orifice nozzles and provides theoretical guidance for hydraulic radial jet drilling process.
Keywords	CFX ; multi‐orifice nozzle ; radial jet drilling ; self‐propelled force ; Technology ; T ; Science ; Q
Subject code	621
Language	English
Publishing date	2020-09-01T00:00:00Z
Publisher	Wiley
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: How Could Peers in Online Health Community Help Improve Health Behavior

Yumei Li / Xiangbin Yan

International Journal of Environmental Research and Public Health, Vol 17, Iss 2995, p

2020 Volume 2995

Abstract: Human behavior is the largest source of variance in health-related outcomes, and the increasingly popular online health communities (OHC) can be used to promote healthy behavior and outcomes. We explored how the social influence (social integration, ... ...

Abstract	Human behavior is the largest source of variance in health-related outcomes, and the increasingly popular online health communities (OHC) can be used to promote healthy behavior and outcomes. We explored how the social influence (social integration, descriptive norms and social support) exerted by online social relationships does affect the health behavior of users. Based on an OHC, we considered the effect of three types of social relationships (friendship, mutual support group and competing group) in the OHC. We found that social integration, descriptive norms and social support (information and emotional support) from the OHC had a positive effect on dietary and exercise behavior. Comparing the effects of different social relationships, we found that the stronger social relationship—friendship—had a stronger effect on health behavior than the mutual support group and competing group. Emotional support had a stronger effect on health behavior than informational support. We also found that the effects of social integration and informational support became stronger as membership duration increased, but the effects of the descriptive norms and emotional support became smaller. This study extended the research on health behavior to the online social environment and explored how the social influence exerted by various social relationships in an OHC affected health behavior. The results could be used for guiding users to make use of online social relationships for changing and maintaining healthy behavior, and helping healthcare websites improve their services.
Keywords	online health community ; social relationship ; social influence ; health behavior ; social integration ; descriptive norm ; Medicine ; R
Subject code	300
Language	English
Publishing date	2020-04-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Network analysis of internet gaming disorder, problematic social media use, problematic smartphone use, psychological distress, and meaning in life among adolescents

Yumei Li / Wenlong Mu / Xuying Xie / Sylvia Y.C.L. Kwok

Digital Health, Vol

2023 Volume 9

Abstract: Background Few studies have examined the connections between psychological distress, meaning in life, internet gaming disorder (IGD), problematic smartphone use (PSU), and problematic social media use (PSMU). Methods The central and bridging nodes of IGD, ...

Abstract	Background Few studies have examined the connections between psychological distress, meaning in life, internet gaming disorder (IGD), problematic smartphone use (PSU), and problematic social media use (PSMU). Methods The central and bridging nodes of IGD, PSMU, and PSU symptoms were investigated using network analysis in China among 742 adolescents ( M age = 15.39, SD = 1.68, range = 12–19; 53.23% female). The relationships between IGD, PSMU, and PSU and associated factors were investigated using a Directed Acyclic Graphs method. Results The results suggested that the central symptoms were withdrawal in IGD, mood modification in PSU, and tolerance in PSMU. Mood modification in IGD, mood modification in PSU, withdrawal in PSMU, and functional impairment in PSMU were the bridge symptoms. Males were more likely to experience symptoms of IGD than females, while females were more likely to need meaning than males. Stress is the root factor, while depression, meaning confusion, meaning anxiety, and meaning avoidance were closely associated with IGD, PSMU, and PSU. Conclusions The current research improved the understanding of IGD, PSMU, and PSU symptoms in teenagers and demonstrated the potential of dynamic systems perspectives on problematic use behaviors and stress/meaning-focused interventions.
Keywords	Computer applications to medicine. Medical informatics ; R858-859.7
Subject code	150
Language	English
Publishing date	2023-03-01T00:00:00Z
Publisher	SAGE Publishing
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Pyomelanin produced by Streptomyces sp. ZL-24 and its protective effects against SH-SY5Y cells injury induced by hydrogen peroxide

Yumei Li / Zhengmao Ye / Peng Lu / Lingchao Lu

Scientific Reports, Vol 11, Iss 1, Pp 1-

2021 Volume 10

Abstract: Abstract A soluble melanin pigment produced by Streptomyces sp. ZL-24 was purified and named StrSM. The elemental analysis of StrSM showed it consists of carbon, hydrogen, and oxygen. The spectrum analysis, including ultraviolet–visible absorption ... ...

Abstract	Abstract A soluble melanin pigment produced by Streptomyces sp. ZL-24 was purified and named StrSM. The elemental analysis of StrSM showed it consists of carbon, hydrogen, and oxygen. The spectrum analysis, including ultraviolet–visible absorption spectrum, Fourier-transform infrared spectrum, and pyrolysis–gas chromatography–mass spectrometry, indicated that StrSM might be pyomelanin. High performance liquid chromatography and liquid chromatography–mass spectra analysis of intermediate metabolite showed the presence of homogentisic acid (HGA). Moreover, the enzyme 4-hydroxyphenylpyruvate dioxygenase, involved in HGA biosynthesis, showed high activity during melanin production. Subsequently, a tyrosinase gene (melC2) and hydroxyphenylpyruvate dioxygenase gene double mutant demonstrated StrSM is pyomelanin. In vitro bioactivity assay showed that StrSM had excellent protective capability against SH-SY5Y cell oxidative injury. To our knowledge, the results firstly provide comprehensive data on Streptomyces pyomelanin identification and a promising candidate compound to treat oxidative injury of neurocytes.
Keywords	Medicine ; R ; Science ; Q
Language	English
Publishing date	2021-08-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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