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  • 1
    Online Resource
    Online Resource
    Hindawi Limited ; 2017
    In:  Shock and Vibration Vol. 2017 ( 2017), p. 1-15
    In: Shock and Vibration, Hindawi Limited, Vol. 2017 ( 2017), p. 1-15
    Abstract: Buckling of tubulars has been the subject of many researches in the past. However, the models in previous research always followed the same assumptions: the friction and rotation effects are ignored. The assumptions are relatively far from the reality. This paper focuses on the rotational drill string in horizontal well. The differential equation of the dynamic buckling is established considering some various factors, including friction, the drill string-borehole interaction, and rotation, and the equations of the critical load of the sinusoidal buckling and the spiral buckling are derived. Furthermore, the friction curve of the drill string and the critical load of the dynamic buckling during rotation are obtained. In addition, the influence of the rotational speed on the dynamic buckling and the axis orbit of the dynamic buckling are also gained. The results show that the critical load of the sinusoidal buckling has nothing to do with the rotational speed while the amplitude and the frequency of the dynamic buckling become larger with the increase of the rotational speed, and the dynamic buckling presents a completely different state with the development of the axial load at different speed ranges.
    Type of Medium: Online Resource
    ISSN: 1070-9622 , 1875-9203
    Language: English
    Publisher: Hindawi Limited
    Publication Date: 2017
    detail.hit.zdb_id: 2070162-7
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  • 2
    Online Resource
    Online Resource
    MDPI AG ; 2024
    In:  Applied Sciences Vol. 14, No. 7 ( 2024-03-27), p. 2820-
    In: Applied Sciences, MDPI AG, Vol. 14, No. 7 ( 2024-03-27), p. 2820-
    Abstract: In this study, a portable magnetic adsorption amphibious robot which can operate on and below the waterline is developed for special curved environments, such as the pile legs of offshore platforms and the outer walls of ships. An open robot integrated control system based on a domestic chip is developed, and two operating modes of local control operation and remote wireless operation are realized. A permanent magnet adsorption scheme combining a magnetic adsorption track and a synchronous belt wheel is designed, static and dynamic analysis of the wall-climbing operation of the robot is carried out, and a kinematic model of the underwater robot is established. The experimental results show that the robot can effectively complete amphibious tasks and can realize the accurate control of attitude in water, proving it to be an effective tool for amphibious tasks, such as operating on the pile legs of offshore platforms and the outer walls of ships.
    Type of Medium: Online Resource
    ISSN: 2076-3417
    Language: English
    Publisher: MDPI AG
    Publication Date: 2024
    detail.hit.zdb_id: 2704225-X
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  • 3
    Online Resource
    Online Resource
    Frontiers Media SA ; 2022
    In:  Frontiers in Pharmacology Vol. 12 ( 2022-1-27)
    In: Frontiers in Pharmacology, Frontiers Media SA, Vol. 12 ( 2022-1-27)
    Abstract: Kinesin family member 2C ( KIF2C ) is known as an oncogenic gene to regulate tumor progression and metastasis. However, its pan-cancer analysis has not been reported. In this study, we comprehensively analyzed the characteristics of KIF2C in various cancers. We found that KIF2C was highly expressed and corresponded to a poor prognosis in various cancers. We also found a significant correlation between KIF2C and clinicopathological characteristics, particularly in cervical cancer, which is the most common gynecological malignancy and is the second leading cause of cancer-related deaths among women worldwide. KIF2C mutation is strongly associated with the survival rate of cervical cancer, and KIF2C expression was significantly upregulated in cervical cancer tissues and cervical cancer cells. Moreover, KIF2C promoted cervical cancer cells proliferation, invasion, and migration in vitro and as well increased tumor growth in vivo . KIF2C knockdown promotes the activation of the p53 signaling pathway by regulating the expression of related proteins. The rescue assay with KIF2C and p53 double knockdown partially reversed the inhibitory influence of KIF2C silencing on cervical cancer processes. In summary, our study provided a relatively comprehensive description of KIF2C as an oncogenic gene and suggested KIF2C as a therapeutic target for cervical cancer.
    Type of Medium: Online Resource
    ISSN: 1663-9812
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2022
    detail.hit.zdb_id: 2587355-6
    SSG: 15,3
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  • 4
    In: Cancer Science, Wiley, Vol. 112, No. 5 ( 2021-05), p. 1811-1821
    Abstract: Ribosomal proteins (RPs) are important components of ribosomes and related to the occurrence and development of tumors. However, little is known about the effects of the RP network on cervical cancer (CC). In this study, we screened differentially expressed RPL34 in CC by high‐throughput quantitative proteome assay. We found that RPL34 acted as a tumor suppressor and was downregulated in CC and inhibited the proliferation, migration, and invasion abilities of CC cells. Next, we verified that RPL34 regulated the CC through the MDM2‐P53 pathway by using Act D medicine, MDM2 inhibitor, and a series of western blotting(WB)assays. Moreover, an antisense lncRNA, RPL34‐AS1, regulated the expression of RPL34 and participated in the tumorigenesis of CC. RPL34 can reverse the effect of RPL34‐AS1 in CC cells. Finally, by RNA‐binding protein immunoprecipitation (RIP) assay we found that eukaryotic initiation factor 4A3 (EIF4A3), which binds to RPL34‐AS1, regulated RPL34‐AS1 expression in CC. Therefore, our findings indicate that RPL34‐AS1–induced RPL34 inhibits CC cell proliferation, invasion, and metastasis through modulation of the MDM2‐P53 signaling pathway, which provides a meaningful target for the early diagnosis and treatment of CC.
    Type of Medium: Online Resource
    ISSN: 1347-9032 , 1349-7006
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2021
    detail.hit.zdb_id: 2115647-5
    detail.hit.zdb_id: 2111204-6
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  • 5
    In: Journal of Translational Medicine, Springer Science and Business Media LLC, Vol. 21, No. 1 ( 2023-02-25)
    Abstract: Cancer-testis antigens (CTAs) are often expressed in tumor and testicular tissues but not in other normal tissues. To date, there has been no comprehensive study of the expression and clinical significance of CTA genes associated with endometrial cancer (EC) development. Additionally, the clinical relevance, biological role, and molecular mechanisms of the CTA gene TTK protein kinase ( TTK ) in EC are yet to be fully understood. Methods Using bioinformatics methods, we comprehensively investigated the genomic, transcriptomic, and epigenetic changes associated with aberrant TTK overexpression in EC samples from the TCGA database. We further investigated the mechanisms of the lower survival associated with TTK dysregulation using single-cell data of EC samples from the GEO database. Cell functional assays were used to confirm the biological roles of TTK in EC cells. Results We identified 80 CTA genes that were more abundant in EC than in normal tissues, and high expression of TTK was significantly linked with lower survival in EC patients. Furthermore, ROC analysis revealed that TTK could accurately distinguish stage I EC tissues from benign endometrial samples, suggesting that TTK has the potential to be a biomarker for early EC detection. We found TTK overexpression was more prevalent in EC patients with high-grade, advanced tumors, serous carcinoma, and TP53 alterations. Furthermore, in EC tissue, TTK expression showed a strong positive correlation with EMT-related genes. With single-cell transcriptome data, we identified a proliferative cell subpopulation with high expression of TTK and known epithelial–mesenchymal transition (EMT)-related genes and transcription factors. When proliferative cells were grouped according to TTK expression levels, the overexpressed genes in the TTK high group were shown to be functionally involved in the control of chemoresistance. Utilizing shRNA to repress TTK expression in EC cells resulted in substantial decreases in cell proliferation, invasion, EMT, and chemoresistance. Further research identified microRNA-21 (miR-21) as a key downstream regulator of TTK-induced EMT and chemoresistance. Finally, the TTK inhibitor AZ3146 was effective in reducing EC cell growth and invasion and enhancing the apoptosis of EC cells generated by paclitaxel. Conclusion Our findings establish the clinical significance of TTK as a new biomarker for EC and an as-yet-unknown carcinogenic function. This present study proposes that the therapeutic targeting of TTK might provide a viable approach for the treatment of EC.
    Type of Medium: Online Resource
    ISSN: 1479-5876
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2023
    detail.hit.zdb_id: 2118570-0
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  • 6
    Online Resource
    Online Resource
    Frontiers Media SA ; 2022
    In:  Frontiers in Cell and Developmental Biology Vol. 10 ( 2022-9-28)
    In: Frontiers in Cell and Developmental Biology, Frontiers Media SA, Vol. 10 ( 2022-9-28)
    Abstract: Cryptotanshinone (CT), a natural compound derived from Salvia miltiorrhiza Bunge that is also known as the traditional Chinese medicine Danshen, exhibits antitumor activity in various cancers. However, it remains unclear whether CT has a potential therapeutic benefit against ovarian cancers. The aim of this study was to test the efficacy of CT in ovarian cancer cells in vitro and using a xenograft model in NSG mice orthotopically implanted with HEY A8 human ovarian cancer cells and to explore the molecular mechanism(s) underlying CT’s antitumor effects. We found that CT inhibited the proliferation, migration, and invasion of OVCAR3 and HEY A8 cells, while sensitizing the cell responses to the chemotherapy drugs paclitaxel and cisplatin. CT also suppressed ovarian tumor growth and metastasis in immunocompromised mice orthotopically inoculated with HEY A8 cells. Mechanistically, CT degraded the protein encoded by the oncogene c-Myc by promoting its ubiquitination and disrupting the interaction with its partner protein Max. CT also attenuated signaling via the nuclear focal adhesion kinase (FAK) pathway and degraded FAK protein in both cell lines. Knockdown of c-Myc using lentiviral CRISPR/Cas9 nickase resulted in reduction of FAK expression, which phenocopies the effects of CT and the c-Myc/Max inhibitor 10058-F4. Taken together, our studies demonstrate that CT inhibits primary ovarian tumor growth and metastasis by degrading c-Myc and FAK and attenuating the FAK signaling pathway.
    Type of Medium: Online Resource
    ISSN: 2296-634X
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2022
    detail.hit.zdb_id: 2737824-X
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  • 7
    In: Machines, MDPI AG, Vol. 11, No. 5 ( 2023-05-12), p. 549-
    Abstract: A circular saw blade is a commonly used tool in wood processing. The transverse vibration of the saw blade plays an important role in processing quality during cutting and affects its service life as well. In the study, the transverse vibration of the circular saw blade was investigated at the constant rotation by the simulation using ANSYS software when changing the cantilever length of the cantilever woodworking CNC circular saw machine. Meanwhile, the transverse vibration of the circular saw blade without and with load was explored by the eddy current sensors for when the detection point was differently away from the center of the circular saw blade. The time domain, probability density distribution, and power spectrum characteristics of the transverse vibration signal were analyzed, and the simulation values were compared with the actual cutting data. The results revealed that under certain conditions, the maximum transverse vibration value of the circular saw blade was the smallest in the simulation, then the middle in no-load, and the largest in actual cutting. The maximum transverse vibration value of the saw blade was increased with the extension of the cantilevered overhang, but gradually and slightly, indicating the transverse vibration was hardly affected by the change in overhang length of less than 300 mm. The finding provides the reference for the structural optimization design of cantilever CNC circular saw machines and the promotion of its application.
    Type of Medium: Online Resource
    ISSN: 2075-1702
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2704328-9
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  • 8
    Online Resource
    Online Resource
    Elsevier BV ; 2020
    In:  Pathology - Research and Practice Vol. 216, No. 4 ( 2020-04), p. 152854-
    In: Pathology - Research and Practice, Elsevier BV, Vol. 216, No. 4 ( 2020-04), p. 152854-
    Type of Medium: Online Resource
    ISSN: 0344-0338
    RVK:
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2020
    detail.hit.zdb_id: 2039756-2
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  • 9
    Online Resource
    Online Resource
    IOP Publishing ; 2020
    In:  IOP Conference Series: Materials Science and Engineering Vol. 758, No. 1 ( 2020-02-01), p. 012076-
    In: IOP Conference Series: Materials Science and Engineering, IOP Publishing, Vol. 758, No. 1 ( 2020-02-01), p. 012076-
    Abstract: Horizontal well technology is an important means to improve drilling efficiency and oil and gas production, but it is easy to generate the lateral vibration of the drill string. This strong lateral vibration of the drill string will further lead to the whirl of the drill string, which will accelerate the wear of the drill string and further lead to the failure of the drill string. According to the rotor dynamics theory and fluid dynamics, the whirling equation of the drill string in horizontal wells is established. The effects of the weight of the drill string, wall friction, internal and external drilling fluid flow velocity and fluid resistance on the whirling of the drill string are studied. The mechanism of inducing the whirling of the horizontal drill string and the boundary conditions for judging the whirling are analyzed. Based on the existing dynamic simulation test equipment of the horizontal drill string in the laboratory, the experimental research on the whirling characteristics of the horizontal drill string is carried out, and the influence laws of the weight on bit and the rotation speed on the whirling of the drill string are studied. The results show that with the development of axial load, the intense of lateral vibration of drill string increases.
    Type of Medium: Online Resource
    ISSN: 1757-8981 , 1757-899X
    Language: Unknown
    Publisher: IOP Publishing
    Publication Date: 2020
    detail.hit.zdb_id: 2506501-4
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