324 results on '"Zhitao Chen"'
Search Results
2. Investigating the causal association between obesity and risk of hepatocellular carcinoma and underlying mechanisms
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Zhitao Chen, Chenchen Ding, Kailei Chen, Yangjun Gu, Xiaoxia Qiu, and Qiyong Li
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Obesity ,Hepatocellular carcinoma ,Mendelian randomization ,Body mass index ,Body fat percentage ,Immune cell infiltration ,Medicine ,Science - Abstract
Abstract Obesity is a global health concern and independent risk factor for cancers including hepatocellular carcinoma (HCC). However, evidence on the causal links between obesity and HCC is limited and inconclusive. This study aimed to investigate the causal relationship between obesity-related traits and HCC risk and explore underlying mechanisms using bioinformatics approaches. Two-sample Mendelian randomization analysis was conducted leveraging publicly available genome-wide association study summary data on obesity traits (body mass index, body fat percentage, waist circumference, waist-to-hip ratio, visceral adipose tissue volume) and HCC. Associations of obesity with primary mechanisms (insulin resistance, adipokines, inflammation) and their effects on HCC were examined. Differentially expressed genes in obesity and HCC were identified and functional enrichment analyses were performed. Correlations with tumor microenvironment (TME) and immunotherapy markers were analyzed. Genetically predicted higher body mass index and body fat percentage showed significant causal relationships with increased HCC risk. Overall obesity also demonstrated causal links with insulin resistance, circulating leptin levels, C-reactive protein levels and risk of severe insulin resistant type 2 diabetes. Four differentially expressed genes (ESR1, GCDH, FAHD2A, DCXR) were common in obesity and HCC. Enrichment analyses indicated their roles in processes like RNA capping, viral transcription, IL-17 signaling and endocrine resistance. They exhibited negative correlations with immune cell infiltration and immunotherapy markers in HCC. Overall obesity likely has a causal effect on HCC risk in Europeans, possibly via influencing primary mechanisms. The identified differentially expressed genes may be implicated in obesity-induced hepatocarcinogenesis through regulating cell cycle, inflammation and immune evasion. Further research on precise mechanisms is warranted.
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- 2024
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3. PPIH acts as a potential predictive biomarker for patients with common solid tumors
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Jun Ye, Jianchao Ying, Haixia Chen, Zhiping Wu, Chaolin Huang, Chuan Zhang, Zhitao Chen, and Haini Chen
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PPIH ,Common solid tumors ,Predictive biomarker ,Combined diagnosis ,TCGA ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Our previous studies have indicated that mRNA and protein levels of PPIH are significantly upregulated in Hepatocellular Carcinoma (LIHC) and could act as predictive biomarkers for patients with LIHC. Nonetheless, the expression and implications of PPIH in the etiology and progression of common solid tumors have yet to be explored, including its potential as a serum tumor marker. Methods We employed bioinformatics analyses, augmented with clinical sample evaluations, to investigate the mRNA and protein expression and gene regulation networks of PPIH in various solid tumors. We also assessed the association between PPIH expression and overall survival (OS) in cancer patients using Kaplan-Meier analysis with TCGA database information. Furthermore, we evaluated the feasibility and diagnostic efficacy of PPIH as a serum marker by integrating serological studies with established clinical tumor markers. Results Through pan-cancer analysis, we found that the expression levels of PPIH mRNA in multiple tumors were significantly different from those in normal tissues. This study is the first to report that PPIH mRNA and protein levels are markedly elevated in LIHC, Colon adenocarcinoma (COAD), and Breast cancer (BC), and are associated with a worse prognosis in these cancer patients. Conversely, serum PPIH levels are decreased in patients with these tumors (LIHC, COAD, BC, gastric cancer), and when combined with traditional tumor markers, offer enhanced sensitivity and specificity for diagnosis. Conclusion Our findings propose that PPIH may serve as a valuable predictive biomarker in tumor patients, and its secreted protein could be a potential serum marker, providing insights into the role of PPIH in cancer development and progression.
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- 2024
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4. Beyond graft function impairment after liver transplantation: the prolonged cold ischemia time impact on recurrence of hepatocellular carcinoma after liver transplantation—a single-center retrospective study
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Jia Yu, Tang Yunhua, Yiwen Guo, Yuqi Dong, Jin long Gong, Tielong Wang, Zhitao Chen, Maogen Chen, Weiqiang Ju, and Xiaoshun He
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Gepatocellular carcinoma ,Liver transplantation ,Prolonged cold ischemia time ,Tumor recurrence ,Allograft dysfunction ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Purpose Hepatocellular carcinoma (HCC) is one of the malignant tumors responsible for high mortality and recurrence rates. Although liver transplantation (LT) is an effective treatment option for HCC, ischemia-reperfusion injury (IRI) is a contributor to HCC recurrence after LT. Moreover, prolonged cold ischemia time (CIT) is a risk factor for IRI during LT, and there is insufficient clinical evidence regarding the impact of CIT on HCC recurrence after LT. Patients and Methods This retrospective study analyzed 420 patients who underwent LT for HCC between February 2015 and November 2020 at The First Affiliated Hospital, Sun Yat-sen University. The duration of CIT was defined as the time from clamping of the donor aorta until portal reperfusion. Results A total of 133 patients (31.7%) experienced tumor recurrence after LT, and CIT > 568 min was the independent risk factor for HCC recurrence (OR, 2.406; 95% CI [1.371–4.220]; p = 0.002). Multivariate Cox’s regression analysis revealed that the recipients’ gender, exceeding Milan criteria, poor differentiation, and alpha-fetoprotein (AFP) ≥400 ng/ml in CIT > 568 min group were independent risk factors for disease-free survival. The peak 7-day postoperative alanine aminotransferase (ALT) level (p 568 min group compared to the CIT ≤ 568 min group. Moreover, the amount of fresh frozen plasma (FFP) infusion during the operation increased (p = 0.02), and the time of mechanical ventilation postoperative was longer (p = 0.045). Conclusion An effective strategy to improve the prognosis is to reduce CIT; this strategy lowers the recurrence of HCC in patients undergoing LT, especially those within the Milan criteria.
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- 2024
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5. The dysregulation of biliary tract microflora is closely related to primary choledocholithiasis: a multicenter study
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Min Xiao, Yankun Zhou, Zhengfei Wang, Wenchao Dai, Di Wang, Zhenmiao Wan, Zhitao Chen, Qiyong Li, and ShuSen Zheng
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Bile microbiota ,Choledocholithiasis ,Gallbladder polyp ,Actinobacteriota ,Enterococcus ,Medicine ,Science - Abstract
Abstract Bile microecology changes play an important role in the occurrence and development of choledocholithiasis. At present, there is no clear report on the difference of bile microecology between asymptomatic patients with gallbladder polyps and choledocholithiasis. This study compared bile microecology between gallbladder polyp patients and patients with choledocholithiasis to identify risk factors for primary choledocholithiasis. This study was conducted in 3 hospitals in different regions of China. Bile samples from 26 patients with gallbladder polyps and 31 patients with choledocholithiasis were collected by laparoscopic cholecystectomy and endoscopic retrograde choledocholithiasis cholangiography (ERCP), respectively. The collected samples were used for 16S ribosomal RNA sequencing and liquid chromatography mass spectrometry analysis. The α-diversity of bile microecological colonies was similar between gallbladder polyp and choledocholithiasis, but the β-diversity was different. Firmicutes, Proteobacteri, Bacteroidota and Actinobacteriota are the most common phyla in the gallbladder polyp group and choledocholithiasis group. However, compared with the gallbladder polyp patients, the abundance of Actinobacteriota has significantly lower in the choledocholithiasis group. At the genera level, the abundance of a variety of bacteria varies between the two groups, and Enterococcus was significantly elevated in choledocholithiasis group. In addition, bile biofilm formation—Pseudomonas aeruginosa was more metabolically active in the choledocholithiasis group, which was closely related to stone formation. The analysis of metabolites showed that a variety of metabolites decreased in the choledocholithiasis group, and the concentration of beta-muricholic acid decreased most significantly. For the first time, our study compared the bile of gallbladder polyp patients with patients with choledocholithiasis, and suggested that the change in the abundance of Actinobacteriota and Enterococcus were closely related to choledocholithiasis. The role of Pseudomonas aeruginosa biofilm in the formation of choledocholithiasis was discovered for the first time, and some prevention schemes for choledocholithiasis were discussed, which has important biological and medical significance.
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- 2024
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6. Enhancing mechanical properties and crack resistance of high-strength SHCC/ECC for durable transportation through ethylene-vinyl acetate polymer modification
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Yanlin Huo, Tianan Liu, Dong Lu, Xiaoyu Han, Huayang Sun, Zhitao Chen, Yazhao Li, Jinguang Huang, and Yingzi Yang
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Strain-hardening cementitious composites (SHCC) ,Engineered cementitious materials (ECC) ,Ethylene-vinyl acetate (EVA) ,Ductility enhancement ,Interfacial bond ,Transit Infrastructure ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Strain-hardening cementitious composites (SHCC) possess excellent ductility and toughness, making them suitable for reinforcement and repair projects of transit infrastructures, such as tunnel linings, bridges, and highways. Especially, polyethylene (PE) fiber is admixed to SHCC for fabricating high-strength PE-SHCC. However, the hydrophobic nature of PE fibers results in relatively weak interfacial frictional bond strength with cementitious matrix, ultimately leading to larger crack widths and wider gaps. This poses durability and safety concerns for the practical applications of PE-SHCC in transit infrastructure. In this study, ethylene-vinyl acetate (EVA) dispersible polymer is selected to address this problem. The effect of admixing EVA on mechanical and direct tensile properties of PE-SHCC is investigated. The compressive strength, first crack strength and matrix fracture toughness of PE-SHCC tended to decrease after EVA modification, however, the tensile strength and tensile strain increased significantly with doping. After that, the single fiber pullout test combined with flaw size/distribution analysis is performed to explore the improvement mechanism of PE-SHCC after EVA modification. It was found that the addition of EVA could significantly improve the interfacial transition zone (ITZ), increase the interfacial friction between PE fibers and matrix, and optimise the defect distribution within the matrix. The recommended dosage of EVA is 3–6 % comprehensive consideration of the tensile strength, strain energy, crack width, and mechanical strengths of the EVA-modified PE-SHCC. The enhancement of mechanical strengths and crack resistance in PE-SHCC contributes to the development of transit infrastructure towards greater reliability, durability, and resilience.
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- 2024
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7. Development and validation of a model for early survival prediction following liver transplantation based on donor and recipient characteristics
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Zhonghao Xie, Xiaohong Lin, Yan Wang, Zhitao Chen, Ping Zeng, Xiaoshun He, Weiqiang Ju, and Maogen Chen
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Liver transplantation ,inflammatory cytokines ,early allograft dysfunction ,fatty liver ,prediction model ,Medicine - Abstract
Background Circulating cytokine levels not only correlate with the progression of liver disease but also serve as indicators for the infection status of the body. Growing evidence points to the connection between donor cytokines and graft function following transplantation. This study set out to explore the clinical significance of donor cytokines in predicting liver transplantation prognosis.Methods Data from 172 deceased donor liver transplantations conducted between 2017 and 2022, with available donor serum cytokine information, were collected. The subjects were randomly divided into estimation (n = 120) and validation (n = 52) groups to establish and validate the model. The newly developed SA10 score was compared against established models EAD, MEAF, L-GrAFT7, and L-GrAFT10.Results Donor IL-10, along with donor age and recipient AST peak value within the first 7 days post-operation, was identified as an independent factor associated with recipient survival and was incorporated into the SA10 score. SA10 exhibited robust predictive capability, particularly for 1-month survival (AUC = 0.90, 95% CI = 0.84–0.96), outperforming EAD (AUC = 0.75, 95% CI = 0.60–0.90, p = 0.04) and L-GrAFT7 (AUC = 0.65, 95% CI = 0.49–0.81, p
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- 2024
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8. The enhancement of astaxanthin production in Phaffia rhodozyma through a synergistic melatonin treatment and zinc finger transcription factor gene overexpression
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Jianping Jia, Zhitao Chen, Qingqing Li, Feifei Li, Siru Liu, and Guoliang Bao
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Phaffia rhodozyma ,astaxanthin ,melatonin ,anti-stress ,signal transduction ,RNA-seq ,Microbiology ,QR1-502 - Abstract
Astaxanthin has multiple physiological functions and is applied widely. The yeast Phaffia rhodozyma is an ideal source of microbial astaxanthin. However, the stress conditions beneficial for astaxanthin synthesis often inhibit cell growth, leading to low productivity of astaxanthin in this yeast. In this study, 1 mg/L melatonin (MT) could increase the biomass, astaxanthin content, and yield in P. rhodozyma by 21.9, 93.9, and 139.1%, reaching 6.9 g/L, 0.3 mg/g DCW, and 2.2 mg/L, respectively. An RNA-seq-based transcriptomic analysis showed that MT could disturb the transcriptomic profile of P. rhodozyma cell. Furthermore, differentially expressed gene (DEG) analysis show that the genes induced or inhibited significantly by MT were mainly involved in astaxanthin synthesis, metabolite metabolism, substrate transportation, anti-stress, signal transduction, and transcription factor. A mechanism of MT regulating astaxanthin synthesis was proposed in this study. The mechanism is that MT entering the cell interacts with components of various signaling pathways or directly regulates their transcription levels. The altered signals are then transmitted to the transcription factors, which can regulate the expressions of a series of downstream genes as the DEGs. A zinc finger transcription factor gene (ZFTF), one of the most upregulated DEGs, induced by MT was selected to be overexpressed in P. rhodozyma. It was found that the biomass and astaxanthin synthesis of the transformant were further increased compared with those in MT-treatment condition. Combining MT-treatment and ZFTF overexpression in P. rhodozyma, the biomass, astaxanthin content, and yield were 8.6 g/L, 0.6 mg/g DCW, and 4.8 mg/L and increased by 52.1, 233.3, and 399.7% than those in the WT strain under MT-free condition. In this study, the synthesis and regulation theory of astaxanthin is deepened, and an efficient dual strategy for industrial production of microbial astaxanthin is proposed.
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- 2024
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9. Planar Compound Eye Lens for Enhanced Light Extraction Efficiency in AlGaN‐Based Deep Ultraviolet LEDs
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Qilong Tan, Jie Zhao, Qixin Li, Huan Liu, Bin Dong, Chenguang He, Zhitao Chen, Wen Zhou, and Ningyang Liu
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deep‐ultraviolet LEDs ,light extraction efficiency ,planar compound eye lens ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
Total internal reflection prevents photons from escaping deep‐ultraviolet (DUV) LED, resulting in serious energy waste and reduced service life. To lift the limitation of extraction ability of AlGaN‐based DUV LEDs, an inspiration was drawn from biological visual systems with wide field, which have obtained highly optimized features through evolution. By reconfiguring planar compound eye lens (PCEL) on the n‐AlGaN surface utilizing bio‐inspired features acquired from praying mantis, light extraction efficiency (LEE) enhancement over 180% is demonstrated both for transverse electric (TE) and magnetic fields by finite difference‐time domain (FDTD) simulation. Owing to its ultrathin planar structure and compatibility of material, PCEL provides a pathway to improve energy utilization efficiency of DUV‐LED utilizing one‐step nanoimprint.
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- 2024
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10. Stretchable and durable HD-sEMG electrodes for accurate recognition of swallowing activities on complex epidermal surfaces
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Ding Zhang, Zhitao Chen, Longya Xiao, Beichen Zhu, RuoXuan Wu, ChengJian Ou, Yi Ma, Longhan Xie, and Hongjie Jiang
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Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Abstract Surface electromyography (sEMG) is widely used in monitoring human health. Nonetheless, it is challenging to capture high-fidelity sEMG recordings in regions with intricate curved surfaces such as the larynx, because regular sEMG electrodes have stiff structures. In this study, we developed a stretchable, high-density sEMG electrode array via layer-by-layer printing and lamination. The electrode offered a series of excellent human‒machine interface features, including conformal adhesion to the skin, high electron-to-ion conductivity (and thus lower contact impedance), prolonged environmental adaptability to resist water evaporation, and epidermal biocompatibility. This made the electrode more appropriate than commercial electrodes for long-term wearable, high-fidelity sEMG recording devices at complicated skin interfaces. Systematic in vivo studies were used to investigate its ability to classify swallowing activities, which was accomplished with high accuracy by decoding the sEMG signals from the chin via integration with an ear-mounted wearable system and machine learning algorithms. The results demonstrated the clinical feasibility of the system for noninvasive and comfortable recognition of swallowing motions for comfortable dysphagia rehabilitation.
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- 2023
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11. Enhancing GaN/AlxGa1−xN-Based Heterojunction Phototransistors: The Role of Graded Base Structures in Performance Improvement
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Lingxia Zhang, Hualong Wu, Chenguang He, Kang Zhang, Yunzhou Liu, Qiao Wang, Longfei He, Wei Zhao, and Zhitao Chen
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ultraviolet photodetector ,GaN/AlGaN phototransistors ,graded base ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
This research explores the architecture and efficacy of GaN/AlxGa1−xN-based heterojunction phototransistors (HPTs) engineered with both a compositionally graded and a doping-graded base. Employing theoretical analysis along with empirical fabrication techniques, HPTs configured with an aluminum compositionally graded base were observed to exhibit a substantial enhancement in current gain. Specifically, theoretical models predicted a 12-fold increase, while experimental evaluations revealed an even more pronounced improvement of approximately 27.9 times compared to conventional GaN base structures. Similarly, HPTs incorporating a doping-graded base demonstrated significant gains, with theoretical predictions indicating a doubling of current gain and experimental assessments showing a 6.1-fold increase. The doping-graded base implements a strategic modulation of hole concentration, ranging from 3.8 × 1016 cm−3 at the base–emitter interface to 3.8 × 1017 cm−3 at the base–collector junction. This controlled gradation markedly contributes to the observed enhancements in current gain. The principal mechanism driving these improvements is identified as the increased electron drift within the base, propelled by the intrinsic electric field inherent to both the compositionally and doping-graded structures. These results highlight the potential of such graded base designs in enhancing the performance of GaN/AlxGa1−xN HPTs and provide crucial insights for the advancement of future phototransistor technologies.
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- 2024
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12. The role of meteorological factors on influenza incidence among children in Guangzhou China, 2019–2022
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Zhitao Chen, Yanhui Liu, Haiyan Yue, Jinbin Chen, Xiangzhi Hu, Lijuan Zhou, Boheng Liang, Guozhen Lin, Pengzhe Qin, Wenru Feng, Dedong Wang, and Di Wu
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meteorological factors ,influenza ,distributed lag non-linear models ,children ,incidence ,Public aspects of medicine ,RA1-1270 - Abstract
ObjectiveAnalyzing the epidemiological characteristics of influenza cases among children aged 0–17 years in Guangzhou from 2019 to 2022. Assessing the relationships between multiple meteorological factors and influenza, improving the early warning systems for influenza, and providing a scientific basis for influenza prevention and control measures.MethodsThe influenza data were obtained from the Chinese Center for Disease Control and Prevention. Meteorological data were provided by Guangdong Meteorological Service. Spearman correlation analysis was conducted to examine the relevance between meteorological factors and the number of influenza cases. Distributed lag non-linear models (DLNM) were used to explore the effects of meteorological factors on influenza incidence.ResultsThe relationship between mean temperature, rainfall, sunshine hours, and influenza cases presented a wavy pattern. The correlation between relative humidity and influenza cases was illustrated by a U-shaped curve. When the temperature dropped below 13°C, Relative risk (RR) increased sharply with decreasing temperature, peaking at 5.7°C with an RR of 83.78 (95% CI: 25.52, 275.09). The RR was increased when the relative humidity was below 66% or above 79%, and the highest RR was 7.50 (95% CI: 22.92, 19.25) at 99%. The RR was increased exponentially when the rainfall exceeded 1,625 mm, reaching a maximum value of 2566.29 (95% CI: 21.85, 3558574.07) at the highest rainfall levels. Both low and high sunshine hours were associated with reduced incidence of influenza, and the lowest RR was 0.20 (95% CI: 20.08, 0.49) at 9.4 h. No significant difference of the meteorological factors on influenza was observed between males and females. The impacts of cumulative extreme low temperature and low relative humidity on influenza among children aged 0–3 presented protective effects and the 0–3 years group had the lowest RRs of cumulative extreme high relative humidity and rainfall. The highest RRs of cumulative extreme effect of all meteorological factors (expect sunshine hours) were observed in the 7–12 years group.ConclusionTemperature, relative humidity, rainfall, and sunshine hours can be used as important predictors of influenza in children to improve the early warning system of influenza. Extreme weather reduces the risk of influenza in the age group of 0–3 years, but significantly increases the risk for those aged 7–12 years.
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- 2024
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13. Pan-cancer analysis revealing the multidimensional expression and prognostic and immunologic roles of TGFB1 in cancer
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Zhitao Chen, Chenchen Ding, Jun Chen, Shusen Zheng, and Qiyong Li
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Medicine (General) ,R5-920 - Abstract
Objective This study aimed to perform an integrated pan-cancer analysis to characterize the expression patterns, prognostic value, genetic alterations, and immunologic roles of transforming growth factor beta 1 (TGFB1) across diverse human cancer types. Methods Bioinformatics analyses were conducted using multiple public databases including The Cancer Genome Atlas, Genotype-Tissue Expression, Clinical Proteomic Tumor Analysis Consortium, TIMER2, GEPIA2, cBioPortal, StringDB, and others. Differential expression, survival, immune correlation, and protein interaction network analyses were performed. Results TGFB1 was overexpressed in several tumor types compared with that in normal tissues. High TGFB1 expression was associated with an advanced stage and poorer prognosis in certain cancers. TGFB1 mutations occurred in 1.3% of 10,967 cases surveyed. TGFB1 expression correlated with tumor-infiltrating immune cells and immunotherapy-related genes. Conclusions This comprehensive multi-omics analysis revealed the complex expression and prognostic landscape of TGFB1 across cancers. TGFB1 is emerging as a potential immunotherapeutic target in certain contexts. Further research should elucidate its multifaceted tumor-promoting and tumor-suppressive mechanisms. Our pan-cancer analysis provides new insights into TGFB1 as a prognostic biomarker and immunotherapeutic target in human cancers, and our findings may guide future preclinical and clinical investigations of TGFB1-directed therapies.
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- 2024
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14. Understanding the roles of Li2CO3 in a sulphoaluminate cement system at negative temperatures
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Yanlin Huo, Sile Hu, Dong Lu, Xiaoyu Han, Huayang Sun, Xiaobing Ma, Tianan Liu, Chen Zhang, Zhitao Chen, Jinguang Huang, and Yingzi Yang
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Sulphoaluminate cement (CSA) ,Li2CO3 ,Hydration ,Mechanical properties ,Negative temperature ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
To overcome the slow development of mechanical strengths of sulphoaluminate cement (CSA) in winter construction, this paper investigates the effects of different amounts of admixing Li2CO3 on the setting time, compressive strength, and cooling curve of CSA paste in negative temperatures (−5 °C, −10 °C, and −20 °C). The influence of admixing Li2CO3 on the hydration process and microstructure of CSA paste in a negative temperature environment is also studied using X-ray diffraction (XRD)-Rietveld quantitative analysis, Thermogravimetry (TG) analysis, and Scanning electron microscopy (SEM) observation. The results show that adding Li2CO3 into CSA can significantly improve the mechanical properties at an early age, shorten the curing time, and reduce the freezing point under negative temperatures. The XRD-Rietveld and TG analysis indicates that adding Li2CO3 can increase the consumption of C4A3S̅ and promote the generation of AFt at negative temperatures. It is recommended that the optimum dosage of Li2CO3 should be 0.16 wt% when used as an admixture for CSA systems in negative temperatures.
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- 2023
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15. Elucidating the causal association between gut microbiota and intrahepatic cholangiocarcinoma through Mendelian randomization analysis
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Zhitao Chen, Weiguang Shi, Kailei Chen, Chicheng Lu, Xinyuan Li, and Qiyong Li
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intrahepatic cholangiocarcinoma ,Mendelian randomization ,gut microbiota ,bioinformatics analysis ,tumor immune microenvironment ,Microbiology ,QR1-502 - Abstract
BackgroundIntrahepatic cholangiocarcinoma (ICC) is an aggressive liver cancer with poor prognosis. The gut microbiota has been linked to ICC, but evidence for causality is lacking. Elucidating causal gut microbiota-ICC links could inform prevention and treatment strategies.Materials and methodsWe performed a bidirectional two-sample Mendelian randomization (MR) study to investigate causal associations between gut microbiota and ICC risk. Genome-wide significant single nucleotide polymorphisms (SNPs) associated with gut microbiota abundances were utilized as instrumental variables (IVs). Multiple methods assessed causality and sensitivity analyses evaluated result robustness. Bioinformatics analysis of genetic loci linked to gut microbiota and ICC examined potential mechanisms.ResultsGenetically predicted increases in Veillonellaceae, Alistipes, Enterobacteriales, and Firmicutes were suggestively associated with higher ICC risk, while increases in Anaerostipes, Paraprevotella, Parasutterella, and Verrucomicrobia appeared protective. Bioinformatics analysis revealed differentially expressed genes near gut microbiota-associated loci may influence ICC through regulating pathways and tumor immune microenvironment.ConclusionOur findings provide suggestive evidence for causal links between specific gut microbiota and ICC risk.
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- 2023
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16. Salicylic acid treatment and overexpression of a novel polyamine transporter gene for astaxanthin production in Phaffia rhodozyma
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Jianping Jia, Feifei Li, Yifei Luan, Siru Liu, Zhitao Chen, and Guoliang Bao
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Phaffia rhodozyma ,astaxanthin ,phytohormone ,antioxidant ,signal transduction ,polyamine transporter ,Biotechnology ,TP248.13-248.65 - Abstract
Phaffia rhodozyma represents an excellent microbial resource for astaxanthin production. However, the yeast’s low astaxanthin productivity poses challenges in scaling up industrial production. Although P. rhodozyma originates from plant material, and phytohormones have demonstrated their effectiveness in stimulating microbial production, there has been limited research on the effects and mechanisms of phytohormones on astaxanthin biosynthesis in P. rhodozyma. In this study, the addition of exogenous salicylic acid (SA) at a concentration as low as 0.5 mg/L significantly enhanced biomass, astaxanthin content, and yield by 20.8%, 95.8% and 135.3% in P. rhodozyma, respectively. Moreover, transcriptomic analysis showed that SA had discernible impact on the gene expression profile of P. rhodozyma cells. Differentially expressed genes (DEGs) in P. rhodozyma cells between the SA-treated and SA-free groups were identified. These genes played crucial roles in various aspects of astaxanthin and its competitive metabolites synthesis, material supply, biomolecule metabolite and transportation, anti-stress response, and global signal transductions. This study proposes a regulatory mechanism for astaxanthin synthesis induced by SA, encompassing the perception and transduction of SA signal, transcription factor-mediated gene expression regulation, and cellular stress responses to SA. Notably, the polyamine transporter gene (PT), identified as an upregulated DEG, was overexpressed in P. rhodozyma to obtain the transformant Prh-PT-006. The biomass, astaxanthin content and yield in this engineered strain could reach 6.6 g/L, 0.35 mg/g DCW and 2.3 mg/L, 24.5%, 143.1% and 199.0% higher than the wild strain at the SA-free condition, respectively. These findings provide valuable insights into potential targets for genetic engineering aimed at achieving high astaxanthin yields, and such advancements hold promise for expediting the industrialization of microbial astaxanthin production.
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- 2023
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17. Novel ceRNA network construction associated with programmed cell death in acute rejection of heart allograft in mice
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Yiwen Guo, Yixi Zhang, Jia Yu, Yuqi Dong, Zhitao Chen, Chuchen Zhu, Xitao Hong, Zhonghao Xie, Min Zhang, Shuai Wang, Yichen Liang, Xiaoshun He, Weiqiang Ju, and Maogen Chen
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ceRNA ,heart transplant ,acute rejection (AR) ,lncRNA ,microRNA ,mRNA ,Immunologic diseases. Allergy ,RC581-607 - Abstract
BackgroundT cell-mediated acute rejection(AR) after heart transplantation(HT) ultimately results in graft failure and is a common indication for secondary transplantation. It’s a serious threat to heart transplant recipients. This study aimed to explore the novel lncRNA-miRNA-mRNA networks that contributed to AR in a mouse heart transplantation model.MethodsThe donor heart from Babl/C mice was transplanted to C57BL/6 mice with heterotopic implantation to the abdominal cavity. The control group was syngeneic heart transplantation with the same kind of mice donor. The whole-transcriptome sequencing was performed to obtain differentially expressed mRNAs (DEmRNAs), miRNAs (DEmiRNAs) and lncRNAs (DElncRNAs) in mouse heart allograft. The biological functions of ceRNA networks was analyzed by GO and KEGG enrichment. Differentially expressed ceRNA involved in programmed cell death were further verified with qRT-PCR testing.ResultsLots of DEmRNAs, DEmiRNAs and DElncRNAs were identified in acute rejection and control after heart transplantation, including up-regulated 4754 DEmRNAs, 1634 DElncRNAs, 182 DEmiRNAs, and down-regulated 4365 DEmRNAs, 1761 DElncRNAs, 132 DEmiRNAs. Based on the ceRNA theory, lncRNA-miRNA-mRNA regulatory networks were constructed in allograft acute rejection response. The functional enrichment analysis indicate that the down-regulated mRNAs are mainly involved in cardiac muscle cell contraction, potassium channel activity, etc. and the up-regulated mRNAs are mainly involved in T cell differentiation and mononuclear cell migration, etc. The KEGG pathway enrichment analysis showed that the down-regulated DEmRNAs were mainly enriched in adrenergic signaling, axon guidance, calcium signaling pathway, etc. The up-regulated DEmRNAs were enriched in the adhesion function, chemokine signaling pathway, apoptosis, etc. Four lncRNA-mediated ceRNA regulatory pathways, Pvt1/miR-30c-5p/Pdgfc, 1700071M16Rik/miR-145a-3p/Pdgfc, 1700071M16Rik/miR-145a-3p/Tox, 1700071M16Rik/miR-145a-3p/Themis2, were finally validated. In addition, increased expression of PVT1, 1700071M16Rik, Tox and Themis2 may be considered as potential diagnostic gene biomarkers in AR.ConclusionWe speculated that Pvt1/miR-30c-5p/Pdgfc, 1700071M16Rik/miR-145a-3p/Pdgfc, 1700071M16Rik/miR-145a-3p/Tox and 1700071M16Rik/miR-145a-3p/Themis2 interaction pairs may serve as potential biomarkers in AR after HT.
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- 2023
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18. Mechanical properties of concrete at low and ultra-low temperatures- a review
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Yanlin Huo, Huayang Sun, Dong Lu, Zhitao Chen, and Yingzi Yang
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Concrete ,Low temperature ,Ultra-low temperature ,Mechanical properties ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Abstract As infrastructure construction advances toward the cold and highland environment, concrete preparation technology and service performance in the cold climate is receiving much attention. The freezing of pore water inside concrete leads to significant changes in its mechanical properties at negative temperatures. Therefore, to ensure the safety of civil engineering structures in cold regions, it is necessary to fully understand the change law and enhancement mechanism of the mechanical properties of concrete and be able to predict mechanical properties at a negative temperature. Since the 1970s, scholars have studied concrete’s negative temperature mechanical properties in different water-content states. This paper presents a comprehensive review of the changes in mechanical properties of concrete at low and ultra-low temperatures and further elucidates the evolution of its compressive strength, tensile strength, flexural strength, elastic modulus, and stress-strain relationship at low temperatures. It was found that the main factors affecting the mechanical properties of concrete at low temperatures were temperature and moisture content. The strength of concrete increases significantly with the decrease in temperature and the increase in moisture content. To better understand and predict the mechanical properties of concrete at low temperatures, the best model was suggested by analyzing the prediction models of different researchers and considering the dispersion of the data. Further, based on the G. Wiedemann pore model, the changes in the internal structure of concrete at low temperatures are described in detail, and the mechanism of its mechanical property enhancement is analyzed.
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- 2022
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19. Advanced hepatocellular carcinoma with MET-amplified contained excellent response to crizotinib: a case report
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Yangjun Gu, Min Xiao, Zhitao Chen, and Qiyong Li
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hepatocellular carcinoma ,next-generation sequencing ,MET ,targeted therapy ,comprehensive cancer therapy ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
IntroductionHepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide. Several novel therapeutic strategies have been developed to prolong the survival of patients with advanced HCC. However, therapeutic decision-making biomarkers owing to the extensive heterogeneity of HCC. Next-generation sequencing (NGS) is generally used in treatment decisions to help patients benefit from genome-directed targeting.Case presentationA 56 year-old male with type-B hepatitis for more than 20 years was admitted to our department and underwent laparoscopic left lateral hepatic lobectomy for hepatocellular carcinoma. Unfortunately, the tumor recurred 1 year later. Despite multiple treatments, the tumor continued to progress and invaded the patient’s 5th thoracic vertebras, leading to hypoesthesia and hypokinesia below the nipple line plane 2 years later. NGS revealed MET amplification, and crizotinib, an inhibitor of MET, was recommended. After administration for a month, tumor marker levels decreased, and the tumor shrunk. The patient has remained in remission since that time.ConclusionsWe report that a patient with high MET amplification benefited from its inhibitor, which was recommended by NGS. This indicates the potential clinical decision support value of NGS and the satisfactory effect of MET inhibitors.
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- 2023
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20. Utilization of hepatitis B surface antigen-positive donors in liver transplantation for recipients with hepatocellular carcinoma: a retrospective and propensity score matching analysis
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Zhitao Chen, Yihao Ma, Yuqi Dong, Chuanbao Chen, Hanyu Wang, Tielong Wang, Jia Yu, Xitao Hong, Maogen Chen, Xiaoshun He, and Weiqiang Ju
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Liver transplantation ,Propensity score matching ,Hepatitis B antigen-positive donor ,Hepatocellular carcinoma ,Progression-free survival ,Overall survival ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Introduction The use of extended criteria donor (ECD) grafts such as donor with infection of hepatitis B virus (HBV) is a potential solution for organ shortage. In this study, we aimed to evaluate the safety and long-term survival of utilization of hepatitis B surface antigen-positive (HBsAg+) donor livers in HCC patients using propensity score matching (PSM) analysis. Methods Forty-eight donors with HBsAg-positive and 279 donors with HBsAg-negative were transplanted and enrolled in this study. PSM analysis were used to eliminate selection bias. Perioperative data and survival were collected and analyzed. Results PSM generated 44 patient pairs. When comparing intra- and post-operative data, no significant difference was found between groups (P > 0.05). Patients with a HBsAg-positive donor had significantly worse progression-free survival (1-year: 65.9% vs. 90.9%; 3-year: 18.1% vs. 70.4%, P = 0.0060) and overall survival (1-year: 84.1% and 95.4%; 3-year: 27.2% vs. 79.5%, P = 0.0039). In multivariate analysis, donor HBsAg-positivity was an independent risk factor for survival and occurrence (P = 0.005 and 0.025, respectively). Conclusion In conclusion, with adequate antiviral prophylaxis and treatment, utilization of HBsAg positive liver grafts did not increase the incidence of early-stage complications. However, patient with an HBsAg-positive graft had poorer progression-free survival and overall survival.
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- 2023
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21. Accelerated aging of unencapsulated flexible GaInP/GaAs/InGaAs solar cells by means of damp heat and thermal cycling tests
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Xiaoxu Wu, Junhua Long, Qiangjian Sun, Xia Wang, Zhitao Chen, Menglu Yu, Xiaolong Luo, Xuefei Li, Huyin Zhao, and Shulong Lu
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Flexible III-V solar cells ,GaAs solar cells ,Damp heat ,Thermal cycling ,Recombination ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The extended damp heat and thermal cycling tests were performed on unencapsulated flexible thin-film GaInP/GaAs/InGaAs solar cells to assess the long-term stability. The solar cells were subjected to 85 °C/85% damp heat test for more than 1000 h and 420 cycles of thermal cycling test between −60 °C and 75 °C, respectively. The performance attenuations of flexible solar cells were less than 2% in both cases, which were due to the slow decline of the open-circuit voltage with aging time. The slight decrease in open voltage was attributed to the increase in reverse saturation current due to the enhanced recombination, which was in good agreement with the calculation based on the two-diode model. The good performance of the unencapsulated flexible GaInP/GaAs/InGaAs solar cells in severe environment indicated the stable and reliable device fabrication art in the experiment.
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- 2023
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22. Correction: Stretchable and durable HD-sEMG electrodes for accurate recognition of swallowing activities on complex epidermal surfaces
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Ding Zhang, Zhitao Chen, Longya Xiao, Beichen Zhu, RuoXuan Wu, ChengJian Ou, Yi Ma, Longhan Xie, and Hongjie Jiang
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Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 - Published
- 2023
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23. Association between gut microbiota and hepatocellular carcinoma from 2011 to 2022: Bibliometric analysis and global trends
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Zhitao Chen, Chenchen Ding, Yangjun Gu, Yahui He, Bing Chen, Shusen Zheng, and Qiyong Li
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gut microbiota ,hepatocellular carcinoma ,bibliometric analysis ,publications ,average citation ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
BackgroundHepatocellular carcinoma (HCC) is a primary malignant tumor responsible for approximately 90% of all liver cancers in humans, making it one of the leading public health problems worldwide. The gut microbiota is a complex microbial ecosystem that can influence tumor formation, metastasis, and resistance to treatment. Therefore, understanding the potential mechanisms of gut microbiota pathogenesis is critical for the prevention and treatment of HCC.Materials and methodsA search was conducted in the Web of Science Core Collection (WoSCC) database for English literature studies on the relationship between gut microbiota and HCC from 2011 to 2022. Bibliometric analysis tools such as VOSviewer, CiteSpace, and R Studio were used to analyze global trends and research hotspots in this field.ResultsA total of 739 eligible publications, comprising of 383 articles and 356 reviews, were analyzed. Over the past 11 years, there has been a rapid increase in the annual number of publications and average citation levels, especially in the last five years. The majority of published articles on this topic originated from China (n=257, 34.78%), followed by the United States of America (n=203, 27.47%), and Italy (n=85, 11.50%). American scholars demonstrated high productivity, prominence, and academic environment influence in the research of this subject. Furthermore, the University of California, San Diego published the most papers (n=24) and had the highest average citation value (value=152.17) in the study of the relationship between gut microbiota and HCC. Schnabl B from the USA and Ohtani N from Japan were the authors with the highest number of publications and average citation value, respectively.ConclusionIn recent years, research on the gut microbiota’s role in HCC has made rapid progress. Through a review of published literature, it has been found that the gut microbiota is crucial in the pathogenesis of HCC and in oncotherapy.
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- 2023
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24. Investigation of actual exposure to facial sheet mask preceding its risk assessment
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Lihong Zhou, Jian Chen, Tian Chen, Huailong Chang, Wenguang Cui, Yuanyuan She, Zhu Li, Wenhua Tang, Dengfeng Yuan, Zhitao Chen, and Jin Su
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Medicine ,Science - Abstract
Abstract The present study aimed to reveal the amount per application of facial sheet masks and its influencing factors in Chinese population to form the base for an accurate exposure assessment. A total of 175 healthy subjects aged 18 years or older were recruited and divided into two subgroups: one group of 35 subjects were asked to apply same mask for 5, 10, 15, 20, 25, and 30 min respectively, and the other 140 subjects were instructed to apply one of four types of facial sheet masks presented in the market for 15 min. Furthermore, phenoxyethanol and methylparaben were measured to reflect actual exposure to chemicals. The sharp increase in the relative exposure to phenoxyethanol (CAS NO.122-99-6) and methylparaben at 25 min and longer suggests applying facial sheet masks for longer than 20 min may drive the exposure to hazardous chemicals to increase significantly. The 90th percentile of amount per application for plant-cellulose, bamboo charcoal fiber, bio-cellulose, and binchotan charcoal fiber-based masks was 5.753, 5.371, 5.017, and 4.821 g respectively. In addition, men and subjects with sebaceous skin demonstrated lower amount per application compared to women and subjects with dry skin, respectively. Finally, our data showed that the larger the contacting area between face and mask, the more amount per application. We concluded that the appropriate time of application should be less than 20 min. And mask fabrics, gender, sebum content, and contacting area could significantly impact the risk assessment of facial sheet masks. Our data for the first time provides insights into a realistic risk assessment of facial sheet masks in Chinese population.
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- 2022
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25. Stress Analysis of Flexible GaInP/GaAs/InGaAs Solar Cells Based on Cu Thin‐Film Substrates
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Zhitao Chen, Junhua Long, Qiangjian Sun, Xia Wang, Xiaoxu Wu, Xufei Li, Menglu Yu, Xiaolong Luo, Huyin Zhao, Yuechun Fu, and Shulong Lu
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III–V solar cells ,Cu substrates ,flexible solar cell stresses ,GaAs solar cells ,Environmental technology. Sanitary engineering ,TD1-1066 ,Renewable energy sources ,TJ807-830 - Abstract
The stress of GaInP/GaAs/InGaAs triple‐junction (3J) solar cells with different thicknesses of Cu thin‐film substrates is analyzed. X‐ray diffractometer and metallographic examination show that the unstable as‐deposited Cu film undergoes room‐temperature self‐annealing, which results in grain growth and changes the internal stress of the Cu film over time. A suitable Cu thickness (18 μm) for 3J solar cells is obtained, whose internal stress can offset the stress caused by the epitaxial mismatch. The flexible 3J solar cell with 18 μm Cu film has the lowest curvature of 8.24 m−1 under the combined effect of thermal stress and lattice mismatch stress. The photovoltaic conversion efficiency reaches 35.02% with the open‐circuit voltage of 3.03 V under AM1.5G spectrum. Cu films with a thickness of 14–28 μm have little effect on the optoelectronic properties of the final device. Reducing the curvature of lattice‐mismatched GaInP/GaAs/InGaAs solar cell devices is beneficial for realizing large‐scale flexible solar cell modules.
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- 2023
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26. Study of dry etched N-polar (Al)GaN surfaces obtained by inductively coupled plasma etching
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Xiaoming Ge, Xuebing Yin, Qiaoyu Zeng, Qi Feng, Xiaohui Wang, Quantong Li, Zhitao Chen, and Chengguo Li
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Al(Ga)N ,N-polar ,ICP etching ,surface roughness ,byproducts ,Physics ,QC1-999 - Abstract
We report the Cl-based inductively coupled plasma etching of N-polar Al(Ga)N layers obtained from layer transfer. It is found that debris appeared on the etched N-polar surface after exposing in air for a short period whereas the etched Al-/Ga-polar surface was clean and smooth. The debris can be completely self-vanished on the N-polar Al0.4Ga0.6N surface after exposing in air for a few hours but still remained on the N-polar GaN surface even after over 1 month. The surface chemical analysis results suggested that the debris is the result of Cl-related byproduct generated during the etching process. Byproducts like Al(Ga)Clx and its derivatives are believed to cover on the N-polar surface after the inductively coupled plasma etching and increase the etched surface roughness significantly. The formation and disappearance of debris are attributed to the formation of Al(Ga)Clx⋅ 6H2O crystals when Al(Ga)Clx absorbs moisture in the air and its spontaneous decomposition on the N-polar surface, respectively. Adding O2/SF6 in the process helps remove Al(Ga)Clx byproducts but at the cost of roughened surface/reduced etch rate. With an additional cleaning process after etching, an uniform and smooth N-polar GaN surface with a low root-mean-square surface roughness of 0.5–0.6 nm has been successfully obtained at a reasonable etch rate (∼150 nm/min). The results can provide valuable guidance for the fabrication of high-performance N-polar GaN devices.
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- 2022
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27. Research on Intelligent Monitoring of Fire Safety and Fire Rescue Plan for Tunnel Operation under Quasi-Unattended Background
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Hao Li, Zhitao Chen, Yanming Lu, Peng Li, Qi-Ang Wang, Zichen Liu, and Shu Li
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tunnels ,fire safety ,intelligent monitoring ,fire rescue plan ,emergency management ,Building construction ,TH1-9745 - Abstract
Tunnel structures account for la large proportion of the structures in mountain highway transportation systems. Most tunnels are located in remote areas in which the geological conditions are complex and harsh and in which the layout of the management facilities along the way is complex. Thus, the management and maintenance costs of various facilities are expensive, the cost of fire safety operations and management is high, and disaster prevention and rescue have a difficult time meeting the objective requirements. Therefore, it is urgent to carry out research on quasi-unmanned operations and intelligent remote monitoring. This study firstly proposes a fire safety intelligent monitoring framework for quasi-unattended tunnels. By making full use of various intelligent sensor monitoring data in the tunnel, the tunnel operation status can be grasped in real time. Then, a fire safety evaluation model can be established through the analytic hierarchy process (AHP), and, based on the monitoring data, the AHP model parameters can be evaluated to realize the real-time evaluation and management of tunnel fire safety. Finally, on the basis of the fire safety intelligent monitoring system and the fire safety evaluation system, an adaptive fire rescue plan formulation scheme is proposed for the quasi-unattended tunnels so as to provide guaranteed support for the rapid automatic response of tunnel fire protection and to provide technical data support for the design and realization of intelligent and efficient tunnel management
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- 2023
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28. Epitaxial Lift-Off of Flexible GaN-Based HEMT Arrays with Performances Optimization by the Piezotronic Effect
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Xin Chen, Jianqi Dong, Chenguang He, Longfei He, Zhitao Chen, Shuti Li, Kang Zhang, Xingfu Wang, and Zhong Lin Wang
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AlGaN/AlN/GaN heterojunction ,Epitaxial lift-off ,Flexible membrane ,Two-dimensional electron gas ,Piezotronic effect ,Technology - Abstract
Abstract High-electron-mobility transistors (HEMTs) are a promising device in the field of radio frequency and wireless communication. However, to unlock the full potential of HEMTs, the fabrication of large-size flexible HEMTs is required. Herein, a large-sized (> 2 cm2) of AlGaN/AlN/GaN heterostructure-based HEMTs were successfully stripped from sapphire substrate to a flexible polyethylene terephthalate substrate by an electrochemical lift-off technique. The piezotronic effect was then induced to optimize the electron transport performance by modulating/tuning the physical properties of two-dimensional electron gas (2DEG) and phonons. The saturation current of the flexible HEMT is enhanced by 3.15% under the 0.547% tensile condition, and the thermal degradation of the HEMT was also obviously suppressed under compressive straining. The corresponding electrical performance changes and energy diagrams systematically illustrate the intrinsic mechanism. This work not only provides in-depth understanding of the piezotronic effect in tuning 2DEG and phonon properties in GaN HEMTs, but also demonstrates a low-cost method to optimize its electronic and thermal properties.
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- 2021
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29. Restricted TcR β chain CDR3 clonotype is associated with resolved acute hepatitis B subjects
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Dangsheng Xiao, Ju Wang, Zhitao Chen, Xiuyuan Jin, Yirui Xie, Dong Yan, and Jiezuan Yang
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T cell receptor ,Complementarity-determining region 3 ,Resolved acute hepatitis B ,HBsAg seroconversion ,High throughput sequencing ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background T cells play an important role in the prognosis of hepatitis B virus (HBV) infection, and are involved in the seroconversion of a patient from HBsAb negative to positive. To compare the T-cell receptor β-chain variable region (TcRBV) complementarity-determining region 3 (CDR3) in subjects with or without hepatitis B surface antigen (HBsAg) convert to hepatitis B surface antibody (HBsAb), the TcRBV was determined using high throughput sequencing (HTS). Methods The clonotype and diversity of CDR3 in peripheral blood mononuclear cells of subjects with resolved acute hepatitis B (AHB, HBsAb+, HBsAg-) (n = 5), chronic hepatitis B (CHB, HBsAb-, HBsAg+) (n = 5), and healthy controls (HC, HBsAb-, HBsAg-) (n = 3) were determined and analyzed using HTS (MiSeq). Results The overlapping rate of CDR3 clones of any two samples in AHB group was 2.00% (1.74% ~ 2.30%), CHB group was 1.77% (1.43% ~ 2.61%), and HC group was 1.82% (1.62% ~ 2.12%), and there was no significant difference among the three groups by Kruskal-Wallis H test. However, among the top 10 cumulative frequencies of clonotypes, only the frequency of clonotype (TcRBV20–1/BD1/BJ1–2) in AHB group was lower than that of HC group (P 0.05). Conclusions Thus, there are 57 TcRBV clonotypes that may be related to HBsAg seroconversion of AHB subjects, but the diversity of TcRBV CDR3 is not significantly related to the HBsAb positive status.
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- 2021
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30. Ischemic-Free Liver Transplantation Reduces the Recurrence of Hepatocellular Carcinoma After Liver Transplantation
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Yunhua Tang, Tielong Wang, Weiqiang Ju, Fangcong Li, Qi Zhang, Zhitao Chen, Jinlong Gong, Qiang Zhao, Dongping Wang, Maogen Chen, Zhiyong Guo, and Xiaoshun He
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ischemia reperfusion injury ,hepatocellular carcinoma ,ischemic-free liver transplantation ,prognosis ,propensity-matched analysis ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Ischemia reperfusion injury (IRI) is an adverse factor for hepatocellular carcinoma (HCC) recurrence after liver transplantation. Ischemic-free liver transplantation (IFLT) is a novel transplant procedure that can largely reduce or even prevent IRI, but the clinical relevance of IFLT and the recurrence of HCC after liver transplantation are still unknown. This retrospective study compared survival outcomes, HCC recurrence, perioperative data and IRI severity following liver transplantation (LT). 30 patients received IFLT and 196 patients received conventional liver transplantation (CLT) were chosen for the entire cohort between June 2017 and August 2020. A 1:3 propensity score matching was performed, 30 IFLT recipients and 85 matched CLT patients were enrolled in propensity-matched cohorts. An univariate and multivariate Cox regression analysis was performed, and showed surgical procedure (CLT vs IFLT) was an independent prognostic factor (HR 3.728, 95% CI 1.172-11.861, P=0.026) for recurrence free survival (RFS) in HCC patients following liver transplantation. In the Kaplan–Meier analysis, the RFS rates at 1 and 3 years after LT in recipients with HCC in the IFLT group were significantly higher than those in the CLT group both in the entire cohort and propensity-matched cohort (P=0.006 and P=0.048, respectively). In addition, patients in the IFLT group had a lower serum lactate level, lower serum ALT level and serum AST level on postoperative Day 1. LT recipients with HCC in the IFLT group had a lower incidence of early allograft dysfunction than LT recipients with HCC in the CLT group. Histological analysis showed no obvious hepatocyte necrosis or apoptosis in IFLT group. In conclusion, IFLT can significantly reduce IRI damage and has the potential to be a useful strategy to reduce HCC recurrence after liver transplantation.
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- 2021
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31. Prognostic Biomarkers and Immunotherapeutic Targets Among CXC Chemokines in Pancreatic Adenocarcinoma
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Jiacheng Huang, Zhitao Chen, Chenchen Ding, Shengzhang Lin, Dalong Wan, and Kuiwu Ren
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pancreatic cancer ,CXC chemokines ,prognostic biomarkers ,immunotherapeutic targets ,bioinformatics ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
BackgroundPancreatic cancer is one of the principal causes of tumor-related death worldwide. CXC chemokines, a subfamily of functional chemotactic peptides, affect the initiation of tumor cells and clinical outcomes in several human malignant tumors. However, the specific biological functions and clinical significance of CXC chemokines in pancreatic cancer have not been clarified.MethodsBioinformatics analysis tools and databases, including ONCOMINE, GEPIA2, the Human Protein Atlas, DAVID, GeneMANIA, cBioPortal, STRING, DGidb, MethSurv, TRRUST, SurvExpress, SurvivalMeth, and TIMER, were utilized to clarify the clinical significance and biological functions of CXC chemokine in pancreatic cancer.ResultsExcept for CXCL11/12, the transcriptional levels of other CXC chemokines in PAAD tissues were significantly elevated, and the expression level of CXCL16 was the highest among these CXC chemokines. Our findings also suggested that all of the CXC chemokines were linked to tumor-immune dysfunction involving the abundance of immune cell infiltration, and the Cox proportional hazard model confirmed that dendritic and CXCL3/5/7/8/11/17 were significantly associated with the clinical outcome of PAAD patients. Furthermore, increasing expressions of CXCL5/9/10/11/17 were related to unfavorable overall survival (OS), and only CXCL17 was a prognostic factor for disease-free survival (DFS) in PAAD patients. The expression pattern and prognostic power of CXC chemokines were further validated in the independent GSE62452 dataset. For the prognostic value of single CpG of DNA methylation of CXC chemokines in patients with PAAD, we identified 3 CpGs of CXCL1, 2 CpGs of CXCL2, 2 CpGs of CXCL3, 3 CpGs of CXCL4, 10 CpGs of CXCL5, 1 CpG of CXCL6, 1 CpG of CXCL7, 3 CpGs of CXCL12, 3 CpGs of CXCL14, and 5 CpGs of CXCL17 that were significantly associated with prognosis in PAAD patients. Moreover, the prognostic value of CXC chemokine signature in PAAD was explored and tested in two independent cohort, and results indicated that the patients in the low-risk group had a better OS compared with the high-risk group. Survival analysis of the DNA methylation of CXC chemokine signature demonstrated that PAAD patients in the high-risk group had longer survival times.ConclusionsThese findings reveal the novel insights into CXC chemokine expression and their biological functions in the pancreatic cancers, which might serve as accurate prognostic biomarkers and suitable immunotherapeutic targets for patients with pancreatic cancer.
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- 2021
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32. Continuous Normothermic Machine Perfusion for Renovation of Extended Criteria Donor Livers Without Recooling in Liver Transplantation: A Pilot Experience
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Zhitao Chen, Xitao Hong, Shanzhou Huang, Tielong Wang, Yihao Ma, Yiwen Guo, Changjun Huang, Qiang Zhao, Zhiyong Guo, Xiaoshun He, Weiqiang Ju, and Maogen Chen
- Subjects
continuous normothermic machine perfusion ,extended criteria donor liver ,early allograft dysfunction ,donor after cardiac death ,allograft ,Surgery ,RD1-811 - Abstract
Background: Ischemia injury affects the recovery of liver allograft function. We propose a novel technique aimed at avoiding a second ischemic injury: transplanting an extended criteria donor (ECD) liver directly under normothermic machine perfusion (NMP) without recooling. We studied two cases to evaluate the efficacy and safety of this technique.Methods: The perioperative characteristics and postoperative outcomes of two recipients of ECD livers were analyzed. Both transplantations were performed with continuous normothermic machine perfusion without recooling.Result: In case 1, the cause of donor death was anoxia, and the donor liver had hypernatremia before procurement. The recipient was diagnosed with decompensated cirrhosis. His model for end-stage liver disease (MELD) score was 38. In case 2, the donor liver was from a donor after cardiac death (DCD), and the donor had elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. The recipient was diagnosed with acute hepatic failure. His MELD score was 35. Both donor livers were maintained under NMP and then transplanted without recooling. The peak ALT and AST levels after surgery were 452 and 770 U/L in case 1 and 100 and 592 U/L in case 2. Neither early allograft dysfunction (EAD) nor primary graft non-function (PNF) was present in these two cases.Conclusion: In conclusion, our results demonstrate that continuous NMP without recooling is efficacious and safe for LT with extended criteria donor livers. Further investigations of this technique will be performed to confirm these promising results.
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- 2021
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33. Clinical significance of blood platelets and mean platelet volume in patients with ulcerative colitis
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Zhitao Chen, Yaqi Lu, Jie Wu, and Heng Zhang
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Medicine (General) ,R5-920 - Abstract
Objectives This retrospective study aimed to investigate and analyze the clinical significance of blood platelets (PLTs) and mean platelet volume (MPV) in patients with ulcerative colitis (UC). Methods A total of 132 patients with UC and 208 healthy subjects were enrolled. PLTs, MPV, platelet-large cell rate (P-LCR), C-reactive protein (CRP), fibrinogen (FIB) and D-dimer were analyzed. Correlations were calculated between disease activity/extent of disease and MPV, PLT, and CRP levels in patients with UC. Results PLT levels were significantly higher while MPV and P-LCR were lower in patients with UC compared with controls. Disease activity was positive correlated with CRP (r = 0.564) and PLT (r = 0.307) but negatively correlated with MPV (r = −0.351). Extent of disease was positively correlated with CRP (r = 0.312) but showed no correlation with PLTs and MPV. FIB and D-dimer were higher in patients with UC, but the difference in FIB levels was not statistically significant. Conclusions PLTs and MPV are potential biomarkers for UC disease activity. These data may help clinicians to attain a more comprehensive judgment of the general condition of patients with UC.
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- 2021
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34. Four Immune-Related Long Non-coding RNAs for Prognosis Prediction in Patients With Hepatocellular Carcinoma
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Muqi Li, Minni Liang, Tian Lan, Xiwen Wu, Wenxuan Xie, Tielong Wang, Zhitao Chen, Shunli Shen, and Baogang Peng
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hepatocellar carcinoma ,long noncoding (lnc) RNAs ,prognosis ,survival ,bioinformation analysis ,Biology (General) ,QH301-705.5 - Abstract
BackgroundLong non-coding RNA (LncRNA) plays an important role in the occurrence and development of hepatocellular carcinoma (HCC). This study aims to establish an immune-related LncRNA model for risk assessment and prognosis prediction in HCC patients.MethodsHepatocellular carcinoma patient samples with complete clinical data and corresponding whole transcriptome expression were obtained from the Cancer Genome Atlas (TCGA). Immune-related genes were acquired from the Gene Set Enrichment Analysis (GSEA) website and matched with LncRNA in the TCGA to get immune-related LncRNA. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used for screening the candidate LncRNAs and calculating the risk coefficient to establish the prognosis model. Patients were divided into a high-risk group and a low-risk group depending on the median risk score. The reliability of the prediction was evaluated in the validation cohort and the whole cohort. GSEA and principal component analysis were used for function evaluation.ResultsA total of 319 samples met the screening criteria and were randomly distributed across the training cohort and the validation cohort. After comparison with the IMMUNE_RESPONSE gene set and the IMMUNE_SYSTEM_PROCESS gene set, a total of 3094 immune-related LncRNAs were screened. Ultimately, four immune-related LncRNAs were used to construct a formula using LASSO regression. According to the formula, the low-risk group showed a higher survival rate than the high-risk group in the validation cohort and the whole cohort. The receiver operating characteristic curves data demonstrated that the risk score was more specific than other traditional clinical characteristics in predicting the 5-year survival rate for HCC.ConclusionThe four-immune-related-LncRNA model can be used for survival prediction in HCC and guide clinical therapy.
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- 2020
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35. Characterization of the Micro-Structural Properties of InAlN/GaN Epilayer Grown by MOCVD
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Youhua Zhu, Tao Hu, Meiyu Wang, Yi Li, Mei Ge, Xinglong Guo, Honghai Deng, and Zhitao Chen
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InAlN ,cathodoluminescence ,threading dislocation ,V-type defect ,Crystallography ,QD901-999 - Abstract
An InAlN/GaN heterostructure has been successfully grown on GaN/sapphire and AlN/sapphire substrate by metal organic chemical vapor deposition. The whole epitaxial quality has been confirmed through X-ray diffraction, while some corresponding micro-structural propagation defects have been characterized by means of transmission electron microscopy. It can be concluded that these defects have been originating from the extended threading dislocation in GaN layer. In addition, with the increasing of acceleration voltage, a series of the cathodoluminescence peak shifting can be clearly observed, and the interesting phenomenon has been attributed to the several complex factors, such as inhomogeneous composition, internal absorption, and so on. Nevertheless, with further optimization of the structural parameters of the epilayers, it can be expected that these experimental results would promote a better epitaxy quality and the optoelectronic device design.
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- 2022
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36. Recent Advances in Fabricating Wurtzite AlN Film on (0001)-Plane Sapphire Substrate
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Hualong Wu, Kang Zhang, Chenguang He, Longfei He, Qiao Wang, Wei Zhao, and Zhitao Chen
- Subjects
AlN ,sapphire ,ultrawide bandgap ,crystal growth ,dislocations ,Crystallography ,QD901-999 - Abstract
Ultrawide bandgap (UWBG) semiconductor materials, with bandgaps far wider than the 3.4 eV of GaN, have attracted great attention recently. As a typical representative, wurtzite aluminum nitride (AlN) material has many advantages including high electron mobility, high breakdown voltage, high piezoelectric coefficient, high thermal conductivity, high hardness, high corrosion resistance, high chemical and thermal stability, high bulk acoustic wave velocity, prominent second-order optical nonlinearity, as well as excellent UV transparency. Therefore, it has wide application prospects in next-generation power electronic devices, energy-harvesting devices, acoustic devices, optical frequency comb, light-emitting diodes, photodetectors, and laser diodes. Due to the lack of low-cost, large-size, and high-ultraviolet-transparency native AlN substrate, however, heteroepitaxial AlN film grown on sapphire substrate is usually adopted to fabricate various devices. To realize high-performance AlN-based devices, we must first know how to obtain high-crystalline-quality and controllable AlN/sapphire templates. This review systematically summarizes the recent advances in fabricating wurtzite AlN film on (0001)-plane sapphire substrate. First, we discuss the control principles of AlN polarity, which greatly affects the surface morphology and crystalline quality of AlN, as well as the electronic and optoelectronic properties of AlN-based devices. Then, we introduce how to control threading dislocations and strain. The physical thoughts of some inspirational growth techniques are discussed in detail, and the threading dislocation density (TDD) values of AlN/sapphire grown by various growth techniques are compiled. We also introduce how to achieve high thermal conductivities in AlN films, which are comparable with those in bulk AlN. Finally, we summarize the future challenge of AlN films acting as templates and semiconductors. Due to the fast development of growth techniques and equipment, as well as the superior material properties, AlN will have wider industrial applications in the future.
- Published
- 2021
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- View/download PDF
37. Self-Attention-Based Conditional Variational Auto-Encoder Generative Adversarial Networks for Hyperspectral Classification
- Author
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Zhitao Chen, Lei Tong, Bin Qian, Jing Yu, and Chuangbai Xiao
- Subjects
Generative Adversarial Network (GAN) ,hyperspectral classification ,self-attention ,Science - Abstract
Hyperspectral classification is an important technique for remote sensing image analysis. For the current classification methods, limited training data affect the classification results. Recently, Conditional Variational Autoencoder Generative Adversarial Network (CVAEGAN) has been used to generate virtual samples to augment the training data, which could improve the classification performance. To further improve the classification performance, based on the CVAEGAN, we propose a Self-Attention-Based Conditional Variational Autoencoder Generative Adversarial Network (SACVAEGAN). Compared with CVAEGAN, we first use random latent vectors to obtain more enhanced virtual samples, which can improve the generalization performance. Then, we introduce the self-attention mechanism into our model to force the training process to pay more attention to global information, which can achieve better classification accuracy. Moreover, we explore model stability by incorporating the WGAN-GP loss function into our model to reduce the mode collapse probability. Experiments on three data sets and a comparison of the state-of-art methods show that SACVAEGAN has great advantages in accuracy compared with state-of-the-art HSI classification methods.
- Published
- 2021
- Full Text
- View/download PDF
38. Effect of nanoparticles on quasi-static and dynamic mechanical properties of strain hardening cementitious composite
- Author
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Zhitao Chen, Yingzi Yang, and Yan Yao
- Subjects
Mechanical engineering and machinery ,TJ1-1570 - Abstract
The nanomaterials-modified strain hardening cementitious composites were prepared in this study. The split Hopkinson pressure bar technique was used to conduct the dynamic compressive test. The dynamic compressive properties were evaluated and compared with the quasi-static properties. The experimental results indicated that the addition of nanomaterials had positive effect on improvement of the strength and toughness of strain hardening cementitious composite. The strain hardening cementitious composite with and without adding nanomaterials showed an obvious strain rate dependence, and the nanomaterials-modified strain hardening cementitious composite was more sensitive to the strain rate.
- Published
- 2019
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39. The role of fluid flow in the dynamics of active nematic defects
- Author
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Luiza Angheluta, Zhitao Chen, M Cristina Marchetti, and Mark J Bowick
- Subjects
active nematics ,active matter ,defect dynamics ,Science ,Physics ,QC1-999 - Abstract
We adapt the Halperin–Mazenko formalism to analyze two-dimensional active nematics coupled to a generic fluid flow. The governing hydrodynamic equations lead to evolution laws for nematic topological defects and their corresponding density fields. We find that ±1/2 defects are propelled by the local fluid flow and by the nematic orientation coupled with the flow shear rate. In the overdamped and compressible limit, we recover the previously obtained active self-propulsion of the +1/2 defects. Non-local hydrodynamic effects are primarily significant for incompressible flows, for which it is not possible to eliminate the fluid velocity in favor of the local defect polarization alone. For the case of two defects with opposite charge, the non-local hydrodynamic interaction is mediated by non-reciprocal pressure-gradient forces. Finally, we derive continuum equations for a defect gas coupled to an arbitrary (compressible or incompressible) fluid flow.
- Published
- 2021
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40. Cutting Performance and Wear/Damage Characteristics of PCBN Tool in Hard Milling
- Author
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Haining Gao, Xianli Liu, and Zhitao Chen
- Subjects
cutting performance ,wear characteristics ,damage characteristics ,PCBN tool ,low-rate damage ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In the intermittent machining of hardened steel for the die and mold industry, determining how to reduce the wear of PCBN (Polycrystalline Cubic Boron Nitride) tools and improve their machining efficiency and quality is an important subject. This study investigated the intermittent machining of hardened steel (Cr12MoV, 59HRC (Rockwell hardness)) using uncoated PCBN tools to determine the cutting performance (cutting force, chip morphology, surface quality, tool life, cutting temperature) and the wear/damage characteristics of the tools. The results showed that the cutting performance of a PCBN tool was better than that of a cemented carbide tool. The wear mechanism on the PCBN tool flank was diffusion wear, adhesive wear, and oxidation wear. The main failure modes of the PCBN tool in the machining process of hardened steel at low speed were tool micro-chipping, the conchoidal damage of the rake face, and the larger damaged area of the flank face. The main failure modes of the PCBN tool in the machining process of hardened steel at high speed were flank wear and high-rate fatigue damage.
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- 2019
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41. Cross-view Aggregation Network For Stereo Image Super-Resolution.
- Author
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Zhitao Chen, Tao Lu, Kanghui Zhao, Bolin Zhu, Zhen Li, Jiaming Wang, and Yanduo Zhang
- Published
- 2024
- Full Text
- View/download PDF
42. Bis(μ-2,2′-{[4-(carboxymethoxy)phenyl]azanediyl}diacetato)bis[(1,10-phenanthroline)copper(II)]
- Author
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Yan Zhao, Zhitao Chen, and Tonghen Pan
- Subjects
Crystallography ,QD901-999 - Abstract
The crystal structure of the binuclear title compound, [Cu2(C12H11NO7)2(C12H8N2)2], consists of a complex molecule, which lies about a crystallographic inversion centre with one half-molecule in the asymmetric unit. The CuII cation is bonded to three N atoms and three O atoms, in a Jahn–Teller-distorted octahedral geometry. The basal plane is defined by the two N atoms from the 1,10-phenathroline and two deprotonated O atoms of the polycarboxylate ligand. The axial positions are occupied by the azane N atom and a bridging carboxylate O atom from the second polycarboxylate ligand. The complex molecules are linked through O—H...O hydrogen bonds into extended chains running parallel to [010].
- Published
- 2010
- Full Text
- View/download PDF
43. A Safety-critical Integrated Planning and Control Method for Autonomous Ground Vehicles.
- Author
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Wei Pan, Yongpo Zhao, Huiyun Sun, Lin Zhang, Zhitao Chen, and Hong Chen
- Published
- 2023
- Full Text
- View/download PDF
44. Edge Guided Learning for Image Super-resolution with Realistic Textures.
- Author
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Zhan Li 0004, Ziyi Zhong, Zhitao Chen, Gengqi Yao, Xi Chen, and Weijian Huang
- Published
- 2022
- Full Text
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45. Network Telemetry by Observing and Recording on Programmable Data Plane.
- Author
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Wen-Hong Lin, Waixi Liu 0001, Gui-Feng Chen, Song Wu, Jin-Jiang Fu, Xing Liang, Sen Ling, and Zhitao Chen
- Published
- 2021
- Full Text
- View/download PDF
46. Scheduling mix-flow in SD-DCN based on Deep Reinforcement Learning with Private Link.
- Author
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Jinjie Lu, Waixi Liu 0001, Yinghao Zhu, Sen Ling, Zhitao Chen, and Jiaqi Zeng
- Published
- 2020
- Full Text
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47. Study of the situation deduction of a domino accident caused by overpressure in LPG storage tank area
- Author
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Jinlong, Men, Hongbing, Ji, Zhitao, Chen, Wenli, Xie, and Lingbo, Zhang
- Published
- 2021
- Full Text
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48. Neural Machine Translation with Attention Based on a New Syntactic Branch Distance.
- Author
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Ru Peng, Zhitao Chen, Tianyong Hao, and Yi Fang
- Published
- 2019
- Full Text
- View/download PDF
49. A case of rare obstructive jaundice induced by concealed displacement of T-tube.
- Author
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Yangjun, Gu, Qingqing, Fang, Zhitao, Chen, and Qiyong, Li
- Subjects
ENDOSCOPIC retrograde cholangiopancreatography ,BILE ducts ,GALLSTONES ,JAUNDICE ,CHOLANGIOGRAPHY - Abstract
We present the case of a 32-year-old woman who was ultimately diagnosed with obstructive jaundice. She exhibited persist jaundice, liver dysfunction with normal drainage of T-tube (400–500 ml per day), and normal stools. Prior to her admission to our department, she had undergone a cholecystectomy and T-tube placement following common bile duct exploration for cholelithiasis. Although her serum bilirubin levels initially decreased post-surgery, it rose sharply after T-tube cholangiography. The diagnosis remained unclear until we performed endoscopic retrograde cholangiopancreatography (ERCP), which revealed that the obstructive jaundice was induced by improper T-tube placement. There were few such presentations reported before, and it's particularly unusual to encounter jaundice following T-tube placement. Moreover, diagnosing and treating this condition can be challenging when T-tube drainage appears normal. Thus, our case report provides a unique contribution to the literature on obstructive jaundice. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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50. Corner milling force prediction and improvement method of aviation thin-walled structural parts
- Author
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Zhitao Chen, Caixu Yue, Xianli Liu, and Steven Y. Liang
- Subjects
Control and Systems Engineering ,Mechanical Engineering ,Industrial and Manufacturing Engineering ,Software ,Computer Science Applications - Abstract
Corner is one of the typical characteristics of aerospace monolithic components. In order to achieve a stable processing environment and reduce the mutation of milling force in the process of machining, the manufacturer has been searching a method to control the milling force of corner machining. Based on the cutting contact relationship and the instantaneous chip thickness, the milling force prediction model of corner machining is established. By analyzing different types of corner contact relationship, the influence of cutting contact angle and cutting arc length on milling force is established. The corner feed rate iterative calculation method is used to improve the corner milling force mutation. The corner milling experiment proves that the proposed method can not only effectively control the corner milling force, but also improve the surface quality of the bottom surface of the workpiece. The proposed method is suitable for automatic programming of multi-corner pocket machining and provides theoretical support for stable machining of frame part.
- Published
- 2023
- Full Text
- View/download PDF
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