28 results on '"Chenchen Geng"'
Search Results
2. The risk of thyroid cancer and sex differences in Hashimoto’s thyroiditis, a meta-analysis
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Yali Le, Chenchen Geng, Xiaoqian Gao, and Ping Zhang
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Hashimoto’s thyroiditis ,Thyroid cancer ,Meta-analysis ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Abstract Background and objective The prevalence of thyroid cancer (TC) has exhibited an upward trajectory in recent years. An accelerating amount of evidence shows a significant association between Hashimoto’s thyroiditis (HT) and TC. The present study encompasses a meticulously designed systematic review and meta-analysis with the aim of scrutinizing the risk of TC and clarifying sex disparities in HT. Methods A comprehensive search was conducted across reputable online databases, including PubMed, Cochrane Library, EMBASE, and Web of Science. English-language publications on the correlation between HT and TC were examined without temporal restrictions. Two authors independently screened the articles and extracted pertinent data. The collected data underwent statistical analysis using the STATA software, enabling the calculation of the pooled Odds Ratio (OR) and 95% confidence intervals (CI). Additionally, a supplementary analysis was conducted on studies incorporating sex-specific data to determine the OR (female vs. male) and the sex-based prevalence of TC in HT. Results A total of 2,845 records were obtained, and 26 retrospective studies were included in this meta-analysis. The results indicated a significant role for HT in TC (OR: 2.22, 95% CI: 1.85–2.67). Supplementary analysis indicated that the prevalence of TC in HT patients was lower in women (0.31, 95% CI: 0.17–0.45) than in men (0.37, 95% CI: 0.21–0.53). However, the result was not statistically significant. Conclusion This systematic review and meta-analysis provide evidence that HT is associated with increasing odds of TC. Regular review of HT patients holds positive clinical significance.
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- 2024
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3. GREB1L overexpression is associated with good clinical outcomes in breast cancer
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Ke Dong, Chenchen Geng, Xiaohong Zhan, Zhi Sun, Qian Pu, Peng Li, Haiyun Song, Guanghui Zhao, and Haidong Gao
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Breast cancer ,GREB1L ,Hedgehog ,Prognosis ,Medicine - Abstract
Abstract Background Breast cancer is the most common malignant tumor among women worldwide. GREB1L is a protein-coding gene. Previous studies have shown that GREB1L plays a vital role in lung and gastric adenocarcinoma. Currently, there is no relevant report about its role in breast cancer. Methods The Cancer Genome Atlas database was used to compare the expression level of GREB1L between tumor and normal tissues. The TISIDB website was used for prognosis analysis. The LinkedOmics database was used to predict the potential biological mechanism of GREB1L in breast cancer. Immunohistochemistry was used to detect the GREB1L expression level in breast tissue. Western blotting was used to detect the GREB1L expression level in cell lines. Transwell assays, CCK-8 cell proliferation assays, and colony formation assays were used to detect the migration, invasion, proliferation, and colony formation abilities of cells. Subcutaneous xenograft models were used to detect the in vivo tumor formation abilities of cells. Results GREB1L is highly expressed in breast cancer tissues and breast cancer cells. KEGG enrichment analysis suggested that GREB1L participates in the regulation of the Hedgehog signaling pathway; changes in GREB1L expression affected the migration and invasion abilities of MCF7 and MDA-MB-231 cells. Although changes in GREB1L expression did not affect their proliferation and colony formation abilities in vitro and in vivo, they affected the expression of tumor metastasis-related genes in vivo. The overexpression of GREB1L in breast cancer predicted a favorable prognosis. Conclusion These results showed that GREB1L is involved in the development of breast cancer, and it may be a potential molecular marker for predicting the prognosis of breast cancer.
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- 2023
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4. Research and experiment on global path planning for indoor AGV via improved ACO and fuzzy DWA
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Zhen Zhou, Chenchen Geng, Buhu Qi, Aiwen Meng, and Jinzhuang Xiao
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ant colony algorithm ,fuzzy control ,global path planning ,agv ,dynamic window approach ,Biotechnology ,TP248.13-248.65 ,Mathematics ,QA1-939 - Abstract
In order to obtain an optimal trajectory for indoor AGV, this paper combined an improved ACO and fuzzy DWA (IACO-DWA) algorithm, which can provide an optimal path with collision-free under higher optimization efficiency. The highlights of this paper are detailed as follows: Firstly, an improved adaptive pseudo-random transition strategy is adopted in the state transition probability with an angle factor. A reward and punishment mechanism is introduced in the pheromone updating strategy, then a path optimization strategy called IACO is proposed for the more optimized path. Secondly, IDWA adopted three fuzzy controllers of direction, security and adjustment coefficients through evaluating directional and safety principles, then improving the angular velocity by processing the linear velocity with linear normalization. By adapting to the changes of the environment, the IDWA parameters can be dynamically adjusted to ensure the optimal running speed and reasonable path of AGV. Thirdly, aiming to deal with the path-planning problem in complex environments, we combined IACO with IDWA, the hybrid algorithm involves dividing the globally optimal path obtained from IACO planning into multiple virtual sub-target points. IDWA completes the path planning by switching between these local target points, thereby improving the efficiency of the path planning. Finally, simulations is verified by Matlab and experiment results on the QBot2e platform are given to verify IACO-DWA algorithm's effectiveness and high performance.
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- 2023
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5. An adaptive tunable Janus emitter with controllable unidirectional emission for thermal management in enclosed spaces
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Feifei Ren, Huan Guan, Hang Wei, Jinxin Gu, Shuhui Liang, Chenchen Geng, Jianjun Li, Shuliang Dou, and Yao Li
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Janus emitter ,Negative emittance modulation ,Positive emittance modulation ,Heat insulation and release ,Thermal management ,Energy industries. Energy policy. Fuel trade ,HD9502-9502.5 ,Renewable energy sources ,TJ807-830 - Abstract
The heating and cooling of enclosure space consume a large part of the global energy and contribute to the rise of extreme weather and the greenhouse effect. The radiative cooling and heating function by emitting infrared waves is a passive thermal management strategy, yet most of the research ignored the effect of inner radiance on the object temperature in enclosed spaces. Herein, a tunable Janus emitter with two types of multilayer configuration consisting of VO2/SiO2/ITO was designed and achieved controllable unidirectional emission for thermal management of enclosed spaces. The Fabry-Perot cavity helps create asymmetrical infrared emission on the separate sides, as well as tunable emissions are produced on both sides when the metal-insulating transition of VO2 occurs. This design results in not only remarkable thermal management within enclosed spaces, but also controllable heat insulation and release ability for outdoor spaces. This work may provide new strategies for energy saving, personal thermal management, and other facilities.
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- 2023
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6. Establishment and validation of a nomogram to predict structural incomplete response in papillary thyroid carcinoma patients: a retrospective study
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Chenchen Geng, Shuxu Tian, Xiaoqian Gao, Xiaoguang Li, Qi Ru, and Ping Zhang
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Medicine (General) ,R5-920 - Abstract
Objective To identify risk factors related to structural incomplete response (SIR) in papillary thyroid carcinoma (PTC) and develop a nomogram for PTC patients. Methods In this respective study, clinical, ultrasonic, and pathological data of PTC patients treated at our institute between 2016 and 2020 were analyzed. Patients were randomly split into training and validation sets at a ratio of 7:3. Multivariate Cox regression analysis was conducted to determine independent prognostic factors. On the basis of these factors, a nomogram was built to predict SIR. P value, concordance index, calibration plots and decision curve analysis were used to evaluate the model. Results Multivariate Cox regression analysis showed that BRAF V600E status, lymph node metastasis, sex, tumor size, margin, and surgical procedure were independent prognostic factors. In the validation set, the concordance index of the nomogram was 0.774 (95% confidence interval: 0.703–0.845). Calibration plots at 3 and 5 years showed no apparent difference between predicted SIR probability and the actual SIR proportion. Additionally, the nomogram had good net clinical benefit according to the decision curve analysis compared with cases that were treat-all or treat-none. Conclusion We build a nomogram to predict individualized outcomes and help postoperative surveillance in PTC patients.
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- 2023
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7. Overexpression of miR-297b-5p in Mouse Insulin-Secreting Cells Promotes Metformin-Mediated Protection Against Stearic Acid-Induced Senescence by Targeting Igf1r
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Qingrui Zhao, Shenghan Su, Yuqing Lin, Xuebei Li, Lingfeng Dan, Chunxiao Yang, Chenchen Geng, Romano Regazzi, Xiaohan Li, Yimeng Dong, Changhao Sun, Xia Chu, and Huimin Lu
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stearic acid ,β-cell senescence ,mirna ,metformin ,type 2 diabetes ,Biochemistry ,QD415-436 ,Biology (General) ,QH301-705.5 - Abstract
Background: A long-term consumption of saturated fat significantly increases the concentration of saturated fatty acids in serum, which accelerates the appearance of senescence markers in β-cells and leads to their dysfunction. An understanding of the mechanisms underlying β-cell senescence induced by stearic acid and the exploration of effective agents preventing it remains largely unclear. Here, we aimed to investigate the protective effect of metformin against stearic acid-treated β-cell senescence and to assess the involvement of miR-297b-5p in this process. Methods: To identify senescence, we measured senescence-associated β-galactosidase activity and the expression of senescence-related genes. Gain and loss of function approaches were applied to explore the role of miR-297b-5p in stearic acid-induced β-cell senescence. Bioinformatics analysis and a luciferase activity assay were used to predict the downstream targets of miR-297b-5p. Results: Stearic acid markedly induced senescence and suppressed miR-297b-5p expression in mouse β-TC6 cells, which were significantly alleviated by metformin. After transfection of miR-297b-5p mimics, stearic acid-evoked β-cell senescence was remarkably prevented. Insulin-like growth factor-1 receptor was identified as a direct target of miR-297b-5p. Inhibition of the insulin-like growth factor-1 receptor prevented stearic acid-induced β-cell senescence and dysfunction. Moreover, metformin alleviates the impairment of the miR-297b-5p inhibitor in β-TC6 cells. Additionally, long-term consumption of a high-stearic-acid diet significantly increased senescence and reduced miR-297b-5p expression in mouse islets. Conclusions: These findings imply that metformin alleviates β-cell senescence by stearic acid through upregulating miR-297b-5p to suppress insulin-like growth factor-1 receptor expression, thereby providing a potential target to not only prevent high fat-diet-induced β-cell dysfunction but also for metformin therapy in type 2 diabetes.
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- 2023
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8. DPP4 Is a Potential Prognostic Marker of Thyroid Carcinoma and a Target for Immunotherapy
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Xiaoqian Gao, Yali Le, Chenchen Geng, Zhen Jiang, Guanghui Zhao, and Ping Zhang
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Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
DPP4 (dipeptidyl peptidase 4) is expressed in many cancers, but the relationship between DPP4 and thyroid carcinoma (THCA) is incompletely understood. We aim to explore the expression of DPP4 in THCA and the correlation between DPP4 expression with the prognosis of THCA and antitumor immunity. We systematically analyzed data from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Gene Expression Omnibus (GEO) databases and explored DPP4 expression, its impact on prognosis, and its relationship with antitumor immunity in THCA. Next, we collected 18 pairs of fresh THCA and adjacent paracancerous tissues and performed RT-qPCR to validate the DPP4 mRNA level. Concurrently, immunohistochemistry (IHC) analysis was performed on 12 pairs of paraffin-embedded tissues of medullary thyroid carcinoma (MTC) and paracancerous tissues to validate the DPP4 protein level. Bioinformatics analysis showed that DPP4 mRNA expression in THCA was significantly higher than that in paracancerous tissues (p
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- 2022
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9. Roles of TiO2 buffer layer for preparation of high performance VO2 thin films with Monoclinic polymorph
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Cong Zhang, Chaoyang Kang, Haitao Zong, Shanshan Liang, Chenchen Geng, and Ming Li
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Physics ,QC1-999 - Abstract
Vanadium dioxide (VO2) thin films with pure Monoclinic phase could be transformed from B-phase by inserting TiO2 buffer layers on transparent amorphous glass substrates at the low temperature of 400 °C. This crystalline transformation might be ascribed to oxygen-deficient environment induced by the TiO2 buffer layer and the template effect of TiO2 layer for M-VO2 phase. The simplicity in phase regulation of the present method and the superior optical and electrical properties of the films may allow its wide applications in thermo-opto-electro sensing devices. Keywords: Vanadium dioxide, TiO2 buffer layers, Photoelectric properties
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- 2018
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10. Excellent near-infrared transmission of Zr-based thin film metallic glasses
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Haitao Zong, Chenchen Geng, Chaoyang Kang, Guohua Cao, Lixin Li, Baoqing Zhang, and Ming Li
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Physics ,QC1-999 - Abstract
Zr50Cu50, Zr47Cu44Al9, Zr46.3Cu43.4Al8.3Nb2 and Zr41.2Ti13.8Cu17.5Ni5Be22.5 thin film metallic glasses (TFMGs) were prepared by pulsed laser deposition (PLD) on glass substrates at room temperature. The effect of thickness on the electrical and optical properties of the Zr-based TFMGs was investigated. It was found that the resistivity of the Zr-based TFMGs basically decreased as the thickness varied from 10 nm to 40 nm. Interestingly, while the transmittance in the visible region decreased significantly with the increase of thickness, the transmittance in the near-infrared range still remained at a high level of larger than 80%. Through the characterization of electrical properties, the high transmittance of the Zr-based TFMGs in the near-infrared range was attributed to their rather low carrier concentration. Our findings provided the possibility for TFMGs to be used as transparent electrodes in the field of near infrared sensors and solar cells. Keywords: Thin film metallic glass, Zr-based alloys, Transmittance, Near infrared
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- 2018
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11. Excellent glass forming ability and plasticity in high entropy Zr20Ti20Hf20M20Be20 (M = Cu, Ni, Co) alloys
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Haitao Zong, Chenchen Geng, Chaoyang Kang, Guohua Cao, Linyan Bian, Lixin Li, Baoqing Zhang, and Ming Li
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Physics ,QC1-999 - Abstract
We reported here the studies of a series of Zr20Ti20Hf20M20Be20 (M = Cu, Ni and Co) quinary high entropy bulk metallic glasses. Glasses with critical diameters (Dc) of 3 mm, 8 mm and 5 mm, respectively has been successfully fabricated by copper mold casting. Strikingly, a plastic strain of 11.6% is achieved in the Zr20Ti20Hf20Cu20Be20 metallic glass. The dynamic fragility the Zr20Ti20Hf20Cu20Be20 alloy is determined from calorimetric measurements. The excellent plasticity is explained to be attributed to relatively higher fragility. Keywords: High entropy alloys, Bulk metallic glasses, Glass forming ability, Mechanical property and fragility
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- 2018
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12. Thermodynamic Analysis of Supercritical CO2 Power Cycle with Fluidized Bed Coal Combustion
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Chenchen Geng, Yingjuan Shao, Wenqi Zhong, and Xuejiao Liu
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Heat ,QC251-338.5 - Abstract
Closed supercritical carbon dioxide (S-CO2) Brayton cycle is a promising alternative to steam Rankine cycle due to higher cycle efficiency at equivalent turbine inlet conditions, which has been explored to apply to nuclear, solar power, waste heat recovery, and coal-fired power plant. This study establishes 300MW S-CO2 power system based on modified recompression Brayton cycle integrated with coal-fired circulating fluidized bed (CFB) boiler. The influences of two stages split flow on system performance have been investigated in detail. In addition, thermodynamic analysis of critical operating parameters has been carried out, including terminal temperature difference, turbine inlet pressure/temperature, reheat stages, and parameters as well as compressor inlet pressure/temperature. The results show that rational distribution of split ratio to the recompressor (SR1) achieves maximal cycle efficiency where heat capacities of both sides in the low temperature recuperator (LTR) realize an excellent matching. The optimal SR1 decreases in the approximately linear proportion to high pressure turbine (HPT) inlet pressure due to gradually narrowing specific heat differences in the LTR. Secondary split ratio to the economizer of CFB boiler (SR2) can recover moderate flue gas heat caused by narrow temperature range and improve boiler efficiency. Smaller terminal temperature difference corresponds to higher efficiency and brings about larger cost and pressure drops of the recuperators, which probably decrease efficiency conversely. Single reheat improves cycle efficiency by 1.5% under the condition of 600°C/600°C/25Mpa while efficiency improvement for double reheat is less obvious compared to steam Rankine cycle largely due to much lower pressure ratio. Reheat pressure and main compressor (MC) inlet pressure have corresponding optimal values. HPT and low pressure turbine (LPT) inlet temperature both have positive influences on system performance.
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- 2018
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13. A New Approach for Evaluating Palatine Tonsillar Hypertrophy in Children Based on Ultrasound: A Pilot Study
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Chenchen Geng, Shuxu Tian, Qian Song, Liu Yang, Ye Li, Huihui Wang, Xueping Tian, and Ling Ge
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Adolescent ,Radiological and Ultrasound Technology ,Child, Preschool ,Palatine Tonsil ,Humans ,Pilot Projects ,Radiology, Nuclear Medicine and imaging ,Hypertrophy ,Child ,Retrospective Studies ,Ultrasonography - Abstract
To develop a novel ultrasound (US) plane to diagnose palatine tonsillar hypertrophy objectively in children.Tonsillar ultrasonography of children (age 2-14 years) who had a clinical diagnosis of tonsillar hypertrophy or not were analyzed retrospectively. Clinical data (including gender, age, body mass index (BMI)), and volume (V) of tonsils measured by the US, were recorded. Furthermore, we found a new US plane to diagnose tonsillar hypertrophy and named it the submental oblique cross-section. In this plane, diameters of the left tonsil, right tonsil, and central oropharynx were designated as T1, T2, and O. Then, we calculated the ratio by the formula (T1 + T2)/O.A total of 172 cases (85 hypertrophy and 87 non-hypertrophy) were included in this study. There were no significant differences in gender (P = .844), age (P = .666), and BMI (P = .089) between the groups. In the non-hypertrophy group, the V of both sides had a positive linear correlation with age or BMI. In contrast, there was no linear correlation between ratio and age or BMI. The area under the curve (AUC) of ratio and V was 0.970 (95%CI: 0.947-0.993) and 0.835 (95%CI: 0.778-0.893) by receiver operating characteristic (ROC) analysis, respectively. The optimal cutoff value of ratio for diagnosis of tonsillar hypertrophy was 2.293 (sensitivity = 88.2%, specificity = 95.4%).We established a new US section to evaluate tonsillar hypertrophy. This approach could be easily acquired and provide a reference value to guide clinical practice.
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- 2022
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14. VO2-Based Infrared Radiation Regulator with Excellent Dynamic Thermal Management Performance
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Jinxin Gu, Hang Wei, Feifei Ren, Huan Guan, Shuhui Liang, Chenchen Geng, Long Li, Jiupeng Zhao, Shuliang Dou, and Yao Li
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General Materials Science - Published
- 2022
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15. Design of stapled peptide-based PROTACs for MDM2/MDMX atypical degradation and tumor suppression
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Si, Chen, Xiang, Li, Yinghua, Li, Xing, Yuan, Chenchen, Geng, Songyan, Gao, Jinyang, Li, Bohan, Ma, Zhe, Wang, Wuyuan, Lu, and Hong-Gang, Hu
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Neoplasms ,Humans ,Medicine (miscellaneous) ,Antineoplastic Agents ,Cell Cycle Proteins ,Proto-Oncogene Proteins c-mdm2 ,Tumor Suppressor Protein p53 ,Peptides ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) - Published
- 2022
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16. Stapled Peptides Targeting SARS-CoV-2 Spike Protein HR1 Inhibit the Fusion of Virus to Its Cell Receptor
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Si Chen, Chenchen Geng, Mengjun Zheng, Jie Qing, Wei-Dong Zhang, Yaxin Tang, Yan Zou, Huaxing Shen, Haoran Peng, Xiang Li, Honggang Hu, and Wei Cong
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chemistry.chemical_classification ,Fusion ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Spike Protein ,Lipid bilayer fusion ,Acute respiratory disease ,Peptide ,Membrane Fusion ,Virus ,Cell biology ,chemistry ,Spike Glycoprotein, Coronavirus ,Drug Discovery ,Molecular Medicine ,Receptor ,Pandemics ,Protein Binding - Abstract
The pandemic of acute respiratory disease in 2019 caused by highly pathogenic and infectious SARS-CoV-2 has seriously endangered human public safety. The 6-HB (HR1-HR2 complex) formation occurring in the process of spike protein-mediated membrane fusion could serve as a conserved and potential target for the design of fusion inhibitors. Based on the HR2 domain of 6-HB, we designed and synthesized 32 stapled peptides using an all-hydrocarbon peptide stapling strategy. Owing to the improved proteolytic stability and higher helical contents, the optimized stapled peptides termed SCH2-1-20 and SCH2-1-27 showed better inhibitory activities against pseudo and authentic SARS-CoV-2 compared to the linear counterpart. Of note, SCH2-1-20 and SCH2-1-27 were proved to interfere with S protein-mediated membrane fusion. Structural modeling indicated similar binding modes between SCH2-1-20 and the linear peptide. These optimized stapled peptides could serve as potent fusion inhibitors in treating and preventing SARS-CoV-2, and the corresponding SAR could facilitate further optimization.
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- 2021
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17. Experimental study on devolatilization characteristics of lignite during pressurized oxy-fuel combustion: Effects of CO2 and H2O
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Chenchen Geng, Wenqi Zhong, Zhoufeng Bian, and Xuejiao Liu
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Fuel Technology ,General Chemical Engineering ,Organic Chemistry ,Energy Engineering and Power Technology - Published
- 2023
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18. Ultra-High Transmission Broadband Tunable VO2 Optical Limiter.
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Huan Guan, Feifei Ren, Shuhui Liang, Jinxin Gu, Chenchen Geng, Hang Wei, Shuliang Dou, Jiupeng Zhao, and Yao Li
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EYE protection ,VANADIUM dioxide ,OXYGEN consumption ,APPROPRIATE technology ,PHOTODETECTORS - Abstract
An optical limiter (OL) is a nonlinear device that protects sensitive photodetectors or human eyes from high-intensity illumination. However, current OLs have low open-state transmittance and a limited turndown ratio in some cases. In this study, first it is demonstrated that combining the insulator-to-metal transition (IMT) of vanadium dioxide (VO2) with anti-reflection layers can enable both high and broadband open-state transmittance (>-0.9 dB at the peak wavelength) while preserving a large turndown ratio (>21.8 dB). Furthermore, optothermal simulation is conducted to analyze the performance of the VO
2 OL under ultrafast laser irradiation. The result reveals that IMT of the VO2 OL occurs at 0.23 µs when the incident laser intensity is 90 kW cm-2 . These benefits offer a promising alternative to OLs in technologies ranging from sensor protection to human eye defense. [ABSTRACT FROM AUTHOR]- Published
- 2023
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19. Tuning the electrical and optical properties of ZrxOy/VO2 thin films by controlling the stoichiometry of ZrxOy buffer layer
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Zunbo Yu, Huanhuan Liu, Guohua Cao, Chaoyang Kang, Haitao Zong, Ming Li, Chenchen Geng, Cong Zhang, and Jiangbin Wu
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Materials science ,business.industry ,Transition temperature ,General Physics and Astronomy ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,Substrate (electronics) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Pulsed laser deposition ,Phase (matter) ,Transmittance ,Optoelectronics ,Thin film ,0210 nano-technology ,business ,Layer (electronics) ,Monoclinic crystal system - Abstract
High-performance vanadium dioxide (VO2) thin films with high luminous transmittance and solar modulation ability were successfully fabricated on ZrxOy/glass substrate by pulsed laser deposition. By controlling the growth temperature of the buffer layer, the stoichiometry and crystal structure of ZrxOy buffer layer can be converted from cubic Zr2O phase to monoclinic ZrO2 phase. Through such a transformation, the luminous transmittance (Tlum), solar modulation ability (ΔTsol), the transition temperature and the width of thermal hysteresis loop have been tuned without diminishing the thermochromic property. It is found that the insertion of ZrO2 layer results in a remarkable enhancement of the luminous transmittance and the solar modulation ability when compared to single-layer VO2 film. The findings in the present work may provide some new strategies for the commercialization of VO2 films in the field of smart energy-efficient windows.
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- 2019
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20. Clinical value of ultrasonic imaging in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis
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Xiaoguang Li, Qiu Zhang, Ruijie Sun, Li Li, Haitong Gong, Xiaoqian Gao, Chenchen Geng, Guzi Wang, and Dayu Liu
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0301 basic medicine ,Cancer Research ,medicine.medical_specialty ,Medullary cavity ,Palpation ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Lymph node ,medicine.diagnostic_test ,business.industry ,ultrasound ,Ultrasound ,Cancer ,Hypopharyngeal cancer ,Blood flow ,Articles ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,cervical lymph node metastasis ,Radiology ,diagnostic value ,business ,hypopharyngeal cancer - Abstract
Clinical value of ultrasonic imaging in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis was investigated. Eighty-nine patients who were diagnosed with hypopharyngeal cancer in Qilu Hospital of Shandong University (Qingdao) from January 2014 to June 2016 were retrospectively analyzed. Sixty-eight patients were diagnosed with hypopharyngeal cancer with cervical lymph node metastasis by pathological sections. Twenty-one patients did not have cervical lymph node metastasis. All the patients were diagnosed by palpation and ultrasound. The lymph node ultrasound images were quantified by computer, and the long/short diameter ratio, the maximum systolic velocity, blood flow resistance of the metastatic and non-metastatic patients were compared. The diagnostic efficacy of palpation and ultrasound was analyzed in the diagnosis of hypopharyngeal cancer with cervical lymph node metastasis. A correlation analysis was carried out between the image features of ultrasound and lymph node metastasis. The long/short diameter ratio, maximum systolic velocity and resistance index of patients with lymph node metastasis were significantly higher than those without lymph node metastasis, with a significant difference (P
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- 2019
21. Kirigami‐Inspired Reconfigurable Thermal Mimetic Device
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Hang Wei, Jinxin Gu, Feifei Ren, Chenchen Geng, Huan Guan, Shuhui Liang, Qingpu Fan, Jiupeng Zhao, Chengyu Wang, Shuliang Dou, and Yao Li
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Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2022
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22. Self-templated method to fabricate VO2 nanoparticles with ultrahigh luminous transmittance for energy-efficient thermochromic windows
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Chenchen Geng, Shuliang Dou, Jiupeng Zhao, Feifei Ren, Jinxin Gu, Hang Wei, Huan Guan, Shuhui Liang, Long Li, Yao Li, and Zhaoshuo Tian
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General Physics and Astronomy ,Surfaces and Interfaces ,General Chemistry ,Condensed Matter Physics ,Surfaces, Coatings and Films - Published
- 2022
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23. A universal approach to fabricating infrared-shielding smart coatings based on vanadium dioxide
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Hang Wei, Xiao Yan, Jinxin Gu, Feifei Ren, Xuejin Dong, Huan Guan, Chenchen Geng, Shuhui Liang, Qingpu Fan, Long Li, Shuliang Dou, and Yao Li
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Renewable Energy, Sustainability and the Environment ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Published
- 2022
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24. Transformation of crystalline structure and photoelectric properties in VO2/glass thin films by inserting TiO2 buffer layers
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Chenchen Geng, Guohua Cao, Cong Zhang, Shanshan Liang, Chaoyang Kang, Liwei Zhang, Ming Li, and Haitao Zong
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Phase transition ,Materials science ,General Physics and Astronomy ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,Crystal structure ,Substrate (electronics) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Buffer (optical fiber) ,0104 chemical sciences ,Surfaces, Coatings and Films ,Pulsed laser deposition ,Amorphous solid ,Chemical engineering ,Thin film ,0210 nano-technology ,Layer (electronics) - Abstract
Vanadium dioxide (VO2) with reversible metal–insulator transition (MIT) is a promising energy-saving material for next-generation smart windows and infrared devices. However, the specific applications are largely limited by controllable preparation with different polymorphs on common glass substrates. Herein, VO2 thin films were prepared on transparent amorphous glass substrates by inserting TiO2 buffer layers using pulsed laser deposition (PLD) technique. The results showed that B-VO2 film would be formed on the amorphous glass substrate at 400 °C. While after inserting TiO2 buffer layer, pure M-VO2 films with clear phase transition properties were obtained. Based on the analysis of X-ray Diffraction (XRD) and Energy Dispersive Spectrometer (EDS) characterization, the crystalline transformation was attributed to the template effect of TiO2 layer and Ti ions diffusion. The characteristics of VO2/TiO2/glass thin films were closely associated with the thickness of TiO2 buffer layer. With 60 nm TiO2 buffer layer, the VO2/TiO2/glass film showed the sharpest resistance change with more than 2.5-order of magnitude across the MIT, and the T-vis value is as high as 53% with the ΔTsol up to 5.2%. Our current results demonstrated the importance of TiO2 buffer layer to the formation of M-VO2 film on amorphous glass substrate, which was very meaningful for the production of energy efficient smart windows in the future.
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- 2019
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25. Excellent near-infrared transmission of Zr-based thin film metallic glasses
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Chaoyang Kang, Guohua Cao, Haitao Zong, Baoqing Zhang, Ming Li, Lixin Li, and Chenchen Geng
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010302 applied physics ,Amorphous metal ,Materials science ,business.industry ,Near-infrared spectroscopy ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,lcsh:QC1-999 ,Characterization (materials science) ,Pulsed laser deposition ,Electrical resistivity and conductivity ,0103 physical sciences ,Electrode ,Transmittance ,Optoelectronics ,Thin film ,0210 nano-technology ,business ,lcsh:Physics - Abstract
Zr50Cu50, Zr47Cu44Al9, Zr46.3Cu43.4Al8.3Nb2 and Zr41.2Ti13.8Cu17.5Ni5Be22.5 thin film metallic glasses (TFMGs) were prepared by pulsed laser deposition (PLD) on glass substrates at room temperature. The effect of thickness on the electrical and optical properties of the Zr-based TFMGs was investigated. It was found that the resistivity of the Zr-based TFMGs basically decreased as the thickness varied from 10 nm to 40 nm. Interestingly, while the transmittance in the visible region decreased significantly with the increase of thickness, the transmittance in the near-infrared range still remained at a high level of larger than 80%. Through the characterization of electrical properties, the high transmittance of the Zr-based TFMGs in the near-infrared range was attributed to their rather low carrier concentration. Our findings provided the possibility for TFMGs to be used as transparent electrodes in the field of near infrared sensors and solar cells. Keywords: Thin film metallic glass, Zr-based alloys, Transmittance, Near infrared
- Published
- 2018
26. Roles of TiO2 buffer layer for preparation of high performance VO2 thin films with Monoclinic polymorph
- Author
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Shanshan Liang, Cong Zhang, Chenchen Geng, Chaoyang Kang, Haitao Zong, and Ming Li
- Subjects
010302 applied physics ,Materials science ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Buffer (optical fiber) ,lcsh:QC1-999 ,Amorphous solid ,Vanadium dioxide ,Chemical engineering ,Present method ,Phase (matter) ,0103 physical sciences ,Thin film ,0210 nano-technology ,Layer (electronics) ,lcsh:Physics ,Monoclinic crystal system - Abstract
Vanadium dioxide (VO2) thin films with pure Monoclinic phase could be transformed from B-phase by inserting TiO2 buffer layers on transparent amorphous glass substrates at the low temperature of 400 °C. This crystalline transformation might be ascribed to oxygen-deficient environment induced by the TiO2 buffer layer and the template effect of TiO2 layer for M-VO2 phase. The simplicity in phase regulation of the present method and the superior optical and electrical properties of the films may allow its wide applications in thermo-opto-electro sensing devices. Keywords: Vanadium dioxide, TiO2 buffer layers, Photoelectric properties
- Published
- 2018
27. Experimental study on oxy-fuel combustion behavior of lignite char and carbon transfer mechanism with isotopic tracing method
- Author
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Chenchen Geng, Zhoufeng Bian, Wenqi Zhong, and Yingjuan Shao
- Subjects
Work (thermodynamics) ,Materials science ,General Chemical Engineering ,Diffusion ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Atmospheric temperature range ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Combustion ,01 natural sciences ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,Chemical engineering ,chemistry ,Fluidized bed ,Environmental Chemistry ,Particle ,Char ,0210 nano-technology ,Carbon - Abstract
In this work, the conventional combustion in O2/Ar and O2/CO2 atmospheres at temperatures of 700–1000 °C and isotopic tracing experiments at 700–800 °C were conducted respectively in a micro fluidized bed reactor to clarify the conversion characteristics of lignite char and influence mechanism of elevated CO2 concentrations. The isotopic method employing C18O18O provides an intuitive insight into the CO2 gasification behavior by tracking the evolution of the 18O atom throughout the oxy-fuel combustion. The results reveal that char conversion rate significantly reduces when the atmosphere is switched from O2/Ar to O2/CO2 at low temperature range (e.g. 700–800 °C), primarily caused by thermo-physical properties of CO2. However, at higher temperature range (e.g. 950–1000 °C), the C-O2 reaction is limited by the external O2 diffusion and the C-CO2 reaction contributes to the carbon consumption, resulting in a higher combustion rate, especially at O2-deficient conditions. The presence of the atomic 18O in the product C18O16O originating from C18O18O confirms that CO2 is indeed involved in the whole oxy-fuel combustion process and the overall reaction could be described as C + C18O18O+16O16O → 2C18O16O. Besides, total contributions to carbon conversion by the C-CO2 reaction decrease as O2 concentrations and particle sizes increasing.
- Published
- 2020
- Full Text
- View/download PDF
28. Influence of the thickness of ZrO2 buffer layer on the electrical and optical properties of VO2 films
- Author
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Chenchen Geng, Jingchao Yang, Ming Li, Haitao Zong, Jiangbin Wu, Chaoyang Kang, Guohua Cao, and Huanhuan Liu
- Subjects
Materials science ,Analytical chemistry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Buffer (optical fiber) ,Electronic, Optical and Magnetic Materials ,Pulsed laser deposition ,Amorphous solid ,010309 optics ,Tetragonal crystal system ,0103 physical sciences ,Thin film ,0210 nano-technology ,Layer (electronics) ,Sheet resistance ,Monoclinic crystal system - Abstract
In this study, high-quality thermochromic vanadium dioxide (VO2) thin films were grown on ZrO2/glass by pulsed laser deposition and were investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), double beam spectrophotometry and Hall Effect measurement system. Based on XRD results, it can be inferred that the crystal structure of ZrO2 buffer layer can be transformed between monoclinic and tetragonal structures with the increase of buffer layer thickness. Photoelectric performance tests showed that the introduction of ZrO2 buffer layer considerably reduced the phase transition temperature (Tc) and hysteresis loop width (ΔH) of the VO2 films and allowed the visible light transmittance (Tlum) and solar modulation ability (ΔTsol) of the films to be tuned effectively. Especially, when the thickness of the ZrO2 buffer layer was 50 nm, the Tc of the VO2 films reached the minimum value of 48 °C. When the ZrO2 buffer layer thickness increased to 125 nm, the sheet resistance change of the VO2 film attained two orders of magnitude, and their Tlum-90°C and ΔTsol were as high as 50.01% and 7.88%, respectively. These results showed that the ZrO2 buffer layer considerably affected the growth of VO2 films on amorphous glass substrates and was beneficial for the application of VO2 in energy-saving smart windows.
- Published
- 2019
- Full Text
- View/download PDF
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