120 results on '"Pan, Di"'
Search Results
2. Relationship between serum albumin level and hospitalization duration following percutaneous coronary intervention for acute coronary syndrome.
- Author
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Pan, Di and Chen, Haibo
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ACUTE coronary syndrome ,SERUM albumin ,PERCUTANEOUS coronary intervention ,LENGTH of stay in hospitals ,NONLINEAR regression - Abstract
Low serum albumin levels increase coronary morbidity, mortality, and postoperative cardiovascular risk. Therefore, this study investigated the relationship between these levels and the length of hospital stay in patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome. A total of 350 patients were divided into quartiles according to serum albumin levels. Univariate and multivariate analyses were performed to identify factors associated with the length of hospital stay. A non-linear regression analysis of serum albumin and length of hospital stay was also performed. The results of the multifactorial analysis revealed low serum albumin levels as an independent predictor of longer hospital stay, even in the fully adjusted model. In the segmented linear regression model, serum albumin level showed a U-shaped relationship with the length of hospital stay. In conclusion, low serum albumin level was an independent predictor of longer hospital stay in patients undergoing PCI for acute coronary syndrome, with shorter stays observed for increasing serum albumin levels. Low serum albumin can be used to identify patients who require longer hospitalization and may need additional nutritional support or interventions to improve their prognosis. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Pedestrian trajectory prediction method based on the Social-LSTM model for vehicle collision.
- Author
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Han, Yong, Lin, Xujie, Pan, Di, Li, Yanting, Su, Liang, Thomson, Robert, and Mizuno, Koji
- Abstract
Techniques for predicting the trajectory of vulnerable road users are important to the development of perception systems for autonomous vehicles to avoid accidents. The most effective trajectory prediction methods, such as Social-LSTM, are often used to predict pedestrian trajectories in normal passage scenarios. However, they can produce unsatisfactory prediction results and data redundancy, as well as difficulties in predicting trajectories using pixel-based coordinate systems in collision avoidance systems. There is also a lack of validations using real vehicle-to-pedestrian collisions. To address these issues, some insightful approaches to improve the trajectory prediction scheme of Social-LSTM were proposed, such methods included transforming pedestrian trajectory coordinates and converting image coordinates to world coordinates. The YOLOv5 detection model was introduced to reduce target loss and improve prediction accuracy. The DeepSORT algorithm was employed to reduce the number of target transformations in the tracking model. Image Perspective Transformation (IPT) and Direct Linear Transformation (DLT) theories were combined to transform the coordinates to world coordinates, identifying the collision location where the accident could occur. The performance of the proposed method was validated by training tests using MS COCO (Microsoft Common Objects in Context) and ETH/UCY datasets. The results showed that the target detection accuracy was more than 90% and the prediction loss tends to decrease with increasing training steps, with the final loss value less than 1%. The reliability and effectiveness of the improved method were demonstrated by benchmarking system performance to two video recordings of real pedestrian accidents with different lighting conditions. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Influences of thermal crown and wear crown of work roll on strip shape in tandem cold rolling using a novel 3D multi-pass FE model.
- Author
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Li, Lianjie, Xie, Haibo, Zhang, Tao, Pan, Di, Liu, Tianwu, Li, Xingsheng, Liu, Xu, Wang, Enrui, Liu, Hongqiang, Sun, Li, and Jiang, Zhengyi
- Abstract
Thermal crown and wear crown of work roll (TWW) are the main interfering factors of loaded roll gap profile in tandem cold rolling (TCR). However, the effect of TWW on the strip shape is not well understood. This paper presents a quantitative study about the effect of TWW on the strip crown and strip flatness based on a novel 3D multi-pass elastic-plastic finite element (EPFE) model that has been validated by industrial trials in the TCR. The results show that the thermal crown introduces the centre wave and quarter wave, while the wear crown brings in the edge wave and edge-centre coupled wave; the thermal crown has a larger influence efficiency on the quadratic strip shape than the wear crown does, while the wear crown exerts a larger influence efficiency on the quartic strip shape than the thermal crown does. In addition, the influence efficiency of TWW on the strip crown decreases nonlinearly with an increase in strip plastic rigidity from Pass 1 (P1) to Pass 5 (P5). This is the first scientific report on the link between the strip plastic rigidity and the effect of TWW on the strip crown, affording the mathematical models for predicting the influence efficiency of TWW based on the strip plastic rigidity at each pass. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Enhancing Escherichia coli Inactivation: Synergistic Mechanism of Ultraviolet Light and High-Voltage Electric Field.
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Zhang, Yihan, Liang, Yun, Pan, Di, Bai, Shupei, Wen, Diya, Tang, Min, Song, Hua, Guo, Xuan, and Han, Hao
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ULTRAVIOLET radiation ,ELECTRIC fields ,ELECTRIC lighting ,ESCHERICHIA coli ,FOOD preservation - Abstract
This study investigated the bactericidal effects of ultraviolet (UV) radiation, a high-voltage electric field (HVEF), and their combination on Escherichia coli. The results indicated that UV and combined disinfection were more effective with longer exposure, leading to significant reductions in microbial activity. Specifically, the single UV disinfection alone reduced activity by 3.3 log after 5 min, while combined disinfection achieved a 4.2 log reduction. In contrast, short-term HVEF treatment did not exhibit significant bactericidal effects, only achieving a reduction of 0.17 log in 5 min. Furthermore, prolonged exposure to both UV disinfection and an HVEF was found to damage cell membranes, ultimately causing cell death, while shorter durations did not. Despite rapid cell count decreases, flow cytometry did not detect apoptotic or necrotic cells, likely due to rapid cell rupture. This study suggests that combining UV radiation and an HVEF could be a promising approach for inhibiting bacterial reproduction, with HVEF enhancing UV effects. These findings provide insights for using combined HVEF and UV disinfection in food safety and preservation. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Single-cell insights: pioneering an integrated atlas of chromatin accessibility and transcriptomic landscapes in diabetic cardiomyopathy.
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Su, Qiang, Huang, Wanzhong, Huang, Yuan, Dai, Rixin, Chang, Chen, Li, Qiu-Yan, Liu, Hao, Li, Zhenhao, Zhao, Yuxiang, Wu, Qiang, and Pan, Di-Guang
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DIABETIC cardiomyopathy ,CHROMATIN ,CARDIAC contraction ,VASCULAR endothelial growth factor receptors ,ENDOTHELIAL cells - Abstract
Background: Diabetic cardiomyopathy (DCM) poses a growing health threat, elevating heart failure risk in diabetic individuals. Understanding DCM is crucial, with fibroblasts and endothelial cells playing pivotal roles in driving myocardial fibrosis and contributing to cardiac dysfunction. Advances in Multimodal single-cell profiling, such as scRNA-seq and scATAC-seq, provide deeper insights into DCM's unique cell states and molecular landscape for targeted therapeutic interventions. Methods: Single-cell RNA and ATAC data from 10x Multiome libraries were processed using Cell Ranger ARC v2.0.1. Gene expression and ATAC data underwent Seurat and Signac filtration. Differential gene expression and accessible chromatin regions were identified. Transcription factor activity was estimated with chromVAR, and Cis-coaccessibility networks were calculated using Cicero. Coaccessibility connections were compared to the GeneHancer database. Gene Ontology analysis, biological process scoring, cell-cell communication analysis, and gene-motif correlation was performed to reveal intricate molecular changes. Immunofluorescent staining utilized various antibodies on paraffin-embedded tissues to verify the findings. Results: This study integrated scRNA-seq and scATAC-seq data obtained from hearts of WT and DCM mice, elucidating molecular changes at the single-cell level throughout the diabetic cardiomyopathy progression. Robust and accurate clustering analysis of the integrated data revealed altered cell proportions, showcasing decreased endothelial cells and macrophages, coupled with increased fibroblasts and myocardial cells in the DCM group, indicating enhanced fibrosis and endothelial damage. Chromatin accessibility analysis unveiled unique patterns in cell types, with heightened transcriptional activity in myocardial cells. Subpopulation analysis highlighted distinct changes in cardiomyocytes and fibroblasts, emphasizing pathways related to fatty acid metabolism and cardiac contraction. Fibroblast-centered communication analysis identified interactions with endothelial cells, implicating VEGF receptors. Endothelial cell subpopulations exhibited altered gene expressions, emphasizing contraction and growth-related pathways. Candidate regulators, including Tcf21, Arnt, Stat5a, and Stat5b, were identified, suggesting their pivotal roles in DCM development. Immunofluorescence staining validated marker genes of cell subpopulations, confirming PDK4, PPARγ and Tpm1 as markers for metabolic pattern-altered cardiomyocytes, activated fibroblasts and endothelial cells with compromised proliferation. Conclusion: Our integrated scRNA-seq and scATAC-seq analysis unveils intricate cell states and molecular alterations in diabetic cardiomyopathy. Identified cell type-specific changes, transcription factors, and marker genes offer valuable insights. The study sheds light on potential therapeutic targets for DCM. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Aspiration Pneumonia.
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Pan, Di, Chung, Samuel, Nielsen, Erik, and Niederman, Michael S.
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ASPIRATION pneumonia ,RESPIRATORY infections ,OLDER people ,HUMAN microbiota ,NEURODEGENERATION - Abstract
Aspiration pneumonia is a lower respiratory tract infection that results from inhalation of foreign material, often gastric and oropharyngeal contents. It is important to distinguish this from a similar entity, aspiration with chemical pneumonitis, as treatment approaches may differ. An evolving understanding of the human microbiome has shed light on the pathogenesis of aspiration pneumonia, suggesting that dysbiosis, repetitive injury, and inflammatory responses play a role in its development. Risk factors for aspiration events involve a complex interplay of anatomical and physiological dysfunctions in the nervous, gastrointestinal, and pulmonary systems. Current treatment strategies have shifted away from anaerobic organisms as leading pathogens. Prevention of aspiration pneumonia primarily involves addressing oropharyngeal dysphagia, a significant risk factor for aspiration pneumonia, particularly among elderly individuals and those with cognitive and neurodegenerative disorders. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Forecasting China carbon price using an error-corrected secondary decomposition hybrid model integrated fuzzy dispersion entropy and deep learning paradigm.
- Author
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Yun, Po, Zhou, Yingtong, Liu, Chenghui, Wu, Yaqi, and Pan, Di
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DEEP learning ,CARBON pricing ,PEARSON correlation (Statistics) ,HILBERT-Huang transform ,FORECASTING ,ENTROPY - Abstract
Forecasting China's carbon price accurately can encourage investors and manufacturing industries to take quantitative investments and emission reduction decisions effectively. The inspiration for this paper is developing an error-corrected carbon price forecasting model integrated fuzzy dispersion entropy and deep learning paradigm, named ICEEMDAN-FDE-VMD-PSO-LSTM-EC. Initially, the improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN) is used to primary decompose the original carbon price. Subsequently, the fuzzy dispersion entropy (FDE) is conducted to identify the high-complexity signals. Thirdly, the variational mode decomposition (VMD) and deep learning paradigm of particle swarm optimized long short-term memory (PSO-LSTM) models are employed to secondary decompose the high-complexity signals and perform out-of-sample forecasting. Finally, the error-corrected (EC) method is conducted to re-modify and strengthen the above-predicted accuracy. The results conclude that the forecasting performance of ICEEMDAN-type secondary decomposition models is significantly better than the primary decomposition models, the deep learning PSO-LSTM-type models have superiority in forecasting China carbon price, and the EC method for improving the forecasting accuracy has been proved. Noteworthy, the proposed model presents the best forecasting accuracy, with the forecasting errors RMSE, MAE, MAPE, and Pearson's correlation are 0.0877, 0.0407, 0.0009, and 0.9998, respectively. Especially, the long-term forecasting ability for 750 consecutive trading prices is outstanding. Those conclusions contribute to judging the carbon price characteristics and formulating market regulations. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Exploring the use of graphene lubricant and TiO2 nanolubricants in micro deep drawing of stainless steel SUS301.
- Author
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Pan, Di, Zhang, Guangqing, Jia, Fanghui, Wu, Hui, Lu, Yao, Zhang, Tao, Li, Lianjie, Lin, Fei, Yang, Ming, and Jiang, Zhengyi
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STAINLESS steel ,GRAPHENE ,ENERGY consumption ,TITANIUM dioxide ,FRICTION ,LUBRICATION & lubricants ,WRINKLE patterns - Abstract
This study investigates the effects of different lubrication conditions on drawing force and microcup formation during micro deep drawing (MDD). Results show that graphene lubricant, in combination with TiO
2 nanolubricants, has the potential to reduce friction during MDD. The peak drawing force was reduced by 15.39% when both lubricants were used together, while the use of TiO2 nanolubricant and 10.0 mg/ml graphene lubricant reduced it by 6.03% and 14.52%, respectively. The study also reveals that lubricants reduce wrinkling during the formation of microcups by minimising energy consumption during the primary formation. However, the combination of TiO2 nanolubricant and graphene lubricant can cause inhomogeneous formation on the upper part of the blank, leading to more apparent wrinkling. Overall, the study highlights the potential of TiO2 nanolubricant and graphene lubricant in reducing friction and improving microcup formation during MDD. [ABSTRACT FROM AUTHOR]- Published
- 2024
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10. Comparative analysis of AEB effectiveness based on typical and atypical scenarios of electric two-wheeler accidents in China.
- Author
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Pan, Di, Han, Yong, Jin, Qianqian, Wu, He, Wang, Bingyu, Huang, Hongwu, and Mizuno, Koji
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- 2024
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11. Ultrasmall Zeolite Subcrystal Catalyst Devoid of Intracrystalline Diffusion Limitation for Bulk Molecule Conversion.
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Du, Ke, Sheng, Zhizheng, Li, He, Gao, Lou, Yan, Tianlan, Yu, Jiayu, Pan, Di, Tan, Zhichao, Xie, Songhai, Ju, Jing, Zhang, Yahong, and Tang, Yi
- Abstract
Constructing zeolite catalysts with excellent mass transfer and active site accessibility is the key to improving their catalytic efficiencies. Herein, a zeolite subcrystal catalyst with high short-range ordering but X-ray amorphism is prepared to minimize the existing molecular mass-transfer barrier of conventional zeolite catalysts. Various characterizations confirm its size of smaller than 10 nm, definite MFI framework, complete opened micropore channel, and abundant accessible acid sites. Moreover, physical and chemisorption results reveal that the high short-range ordering MFI zeolite subcrystal possesses negligible intracrystalline diffuse limitation and utmost accessibility for the active site. As anticipated, the zeolite subcrystal catalyst not only demonstrates high cracking efficiency in polyolefin cracking reactions but also exhibits outstanding catalytic activity and resistance to carbon deposition in macromolecular furfuryl alcohol etherification reaction. The controlled MFI zeolite subcrystal catalyst synthesis strategy is expected to extend to a variety of microporous materials. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Efficacy and Safety of Hetrombopag for Thrombocytopenia in Patients with Advanced Solid Tumors: A Retrospective Study.
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Liu, Haonan, Ma, Xiao, Pan, Di, Cao, Menghan, Han, Zhengxiang, and Wang, Hongmei
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DRUG efficacy ,CANCER chemotherapy ,CELL receptors ,RETROSPECTIVE studies ,ACQUISITION of data ,FISHER exact test ,CANCER patients ,MEDICAL records ,CHI-squared test ,PLATELET count ,DESCRIPTIVE statistics ,THROMBOCYTOPENIA ,TUMORS ,MOLECULAR structure ,DRUG side effects ,PATIENT safety ,EVALUATION - Abstract
Objective. To analyze and evaluate the clinical value of hetrombopag in cancer therapy-induced thrombocytopenia (CTIT) caused by antitumor therapy for malignant tumors and to provide scientific evidence support for clinical application in the real-world setting. Methods. The clinical data of CTIT patients with advanced solid tumors who received hetrombopag were analyzed retrospectively. The proportion of patients with different characteristics who recovered platelet count to ≥75 × 109/L at day 14 and the effective rate of platelet elevation was compared by the χ
2 test or Fisher exact probability method. P < 0.05 was considered statistically significant. Results. A total of 60 CTIT patients who received hetrombopag at our site from July 2021 to October 2022 were finally included in this study. The proportion of patients who achieved therapeutic effect within (7 ± 2) days after treatment was 26.7% (16/60), among which 20.0% (12/60) patients had platelet count recovered to ≥100 × 109/L, and 25.0% (15/60) patients had platelet count increase from baseline ≥50 × 109/L. Within (14 ± 2) days of treatment with hetrombopag, 66.7% (40/60) of patients achieved treatment response, of whom 56.7% (34/60) had platelet counts ≥100 × 109/L and 53.3% (32/60) had platelet counts ≥50 × 109/L increase from baseline. In addition, no treatment-related adverse events occurred during the treatment period. Conclusion. This retrospective study provides preliminary evidence that hetrombopag increases platelets in CTIT patients receiving antitumor therapy for advanced solid tumors. [ABSTRACT FROM AUTHOR]- Published
- 2023
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13. Extreme Risk Measurement of Carbon Market Considering Multifractal Characteristics.
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Zhu, Dandan, Zhang, Chen, and Pan, Di
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Influenced by the global economy, politics, energy and other factors, the price of carbon market fluctuates sharply. It is of great practical significance to explore a suitable measurement method of extreme risk of carbon market. Considering that the return series of carbon market has the characteristics of leptokurtosis, fat tail, skewness and multifractal, and there maybe many extreme risk values in the carbon market, this paper introduces the Skewed-t distribution which can describe the characteristics of leptokurtosis, fat tail and skewness of return series into MSM model which can describe multifractal characteristic of return series to model volatility of carbon market. On the basis, based on the extreme value theory, this paper constructs Skewed-t-MSM-EVT model to measure extreme risk of carbon market. This paper chooses EUA market as the object to study extreme risk of carbon market, and draws the following conclusions: Skewed-t-MSM-EVT model has significantly higher prediction accuracy for carbon market's VaR than MSM-EVT models under other distributions (including normal distribution, t distribution, GED distribution); Skewed-t-MSM-EVT model is superior to traditional Skewed-t-FIGARCH-EVT and Skewed-t-GARCH-EVT models in predicting carbon market's VaR. This research has important practical significance for accurately grasping the risk of carbon market and promoting energy conservation and emission reduction. [ABSTRACT FROM AUTHOR]
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- 2023
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14. Potato Leaf Chlorophyll Content Estimation through Radiative Transfer Modeling and Active Learning.
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Ma, Yuanyuan, Qiu, Chunxia, Zhang, Jie, Pan, Di, Zheng, Chunkai, Sun, Heguang, Feng, Haikuan, and Song, Xiaoyu
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CROP growth ,POTATOES ,ACTIVE learning ,RADIATIVE transfer ,CHLOROPHYLL ,KRIGING ,POTASSIUM fertilizers - Abstract
Leaf chlorophyll content (LCC) significantly correlates with crop growth conditions, nitrogen content, yield, etc. It is a crucial indicator for elucidating the senescence process of plants and can reflect their growth and nutrition status. This study was carried out based on a potato nitrogen and potassium fertilizer gradient experiment in the year 2022 at Keshan Farm, Qiqihar Branch of Heilongjiang Agricultural Reclamation Bureau. Leaf hyperspectral and leaf chlorophyll content data were collected at the potato tuber formation, tuber growth, and starch accumulation periods. The PROSPECT-4 radiative transfer model was employed to construct a look-up table (LUT) as a simulated data set. This was accomplished by simulating potato leaves' spectral reflectance and chlorophyll content. Then, the active learning (AL) technique was used to select the most enlightening training samples from the LUT based on the measured potato data. The Gaussian process regression (GPR) algorithm was finally employed to construct the inversion models for the chlorophyll content of potato leaves for both the whole and single growth periods based on the training samples selected by the AL method and the ground measured data of the potatoes. The R
2 values of model validation accuracy for the potato whole plantation period and three single growth periods are 0.742, 0.683, 0.828, and 0.533, respectively with RMSE values of 4.207, 4.364, 2.301, and 3.791 µg/cm2 . Compared with the LCC inversion accuracy through LUT with a cost function, the validation accuracies of the GPR_PROSPECT-AL hybrid model were improved by 0.119, 0.200, 0.328, and 0.255, and the RMSE were reduced by 3.763, 2.759, 0.118, and 5.058 µg/cm2 , respectively. The study results indicate that the hybrid method combined with the radiative transfer model and active learning can effectively select informative training samples from a data pool and improve the accuracy of potato LCC estimation, which provides a valid tool for accurately monitoring crop growth and growth health. [ABSTRACT FROM AUTHOR]- Published
- 2023
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15. Identification of the Initial Anthesis of Soybean Varieties Based on UAV Multispectral Time-Series Images.
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Pan, Di, Li, Changchun, Yang, Guijun, Ren, Pengting, Ma, Yuanyuan, Chen, Weinan, Feng, Haikuan, Chen, Riqiang, Chen, Xin, and Li, Heli
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MULTISPECTRAL imaging ,LEAF area index ,STANDARD deviations ,GAUSSIAN function ,SOYBEAN ,GENOTYPE-environment interaction - Abstract
Accurate and high-throughput identification of the initial anthesis of soybean varieties is important for the breeding and screening of high-quality soybean cultivars in field trials. The objectives of this study were to identify the initial day of anthesis (IA
DAS ) of soybean varieties based on remote sensing multispectral time-series images acquired by unmanned aerial vehicles (UAVs), and analyze the differences in the initial anthesis of the same soybean varieties between two different climatic regions, Shijiazhuang (SJZ) and Xuzhou (XZ). First, the temporal dynamics of several key crop growth indicators and spectral indices were analyzed to find an effective indicator that favors the identification of IADAS , including leaf area index (LAI), above-ground biomass (AGB), canopy height (CH), normalized-difference vegetation index (NDVI), red edge chlorophyll index (CIred edge), green normalized-difference vegetation index (GNDVI), enhanced vegetation index (EVI), two-band enhanced vegetation index (EVI2) and normalized-difference red-edge index (NDRE). Next, this study compared several functions, like the symmetric gauss function (SGF), asymmetric gauss function (AGF), double logistic function (DLF), and fourier function (FF), for time-series curve fitting, and then estimated the IADAS of soybean varieties with the first-order derivative maximal feature (FDmax) of the CIred edge phenology curves. The relative thresholds of the CIred edge curves were also used to estimate IADAS , in two ways: a single threshold for all of the soybean varieties, and three different relative thresholds for early, middle, and late anthesis varieties, respectively. Finally, this study presented the variations in the IADAS of the same soybean varieties between two different climatic regions and discussed the probable causal factors. The results showed that CIred edge was more suitable for soybean IADAS identification compared with the other investigated indicators because it had no saturation during the whole crop lifespan. Compared with DLF, AGF and FF, SGF provided a better fitting of the CIred edge time-series curves without overfitting problems, although the coefficient of determination (R2 ) and root mean square error (RMSE) were not the best. The FDmax of the SGF-fitted CIred edge curve (SGF_CIred edge) provided good estimates of the IADAS , with an RMSE and mean average error (MAE) of 3.79 days and 3.00 days, respectively. The SGF-fitted_CIred edge curve can be used to group the soybean varieties into early, middle and late groups. Additionally, the accuracy of the IADAS was improved (RMSE = 3.69 days and MAE = 3.09 days) by using three different relative thresholds (i.e., RT50, RT55, RT60) for the three flowering groups compared to when using a single threshold (RT50). In addition, it was found that the IADAS of the same soybean varieties varied greatly when planted in two different climatic regions due to the genotype–environment interactions. Overall, this study demonstrated that the IADAS of soybean varieties can be identified efficiently and accurately based on UAV remote sensing multispectral time-series data. [ABSTRACT FROM AUTHOR]- Published
- 2023
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16. Enhanced Performance of Micro Deep Drawing through the Application of TiO 2 Nanolubricant and Graphene Lubricants on SUS 301 Stainless Steel Foil.
- Author
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Pan, Di, Zhang, Guangqing, Jia, Fanghui, Lu, Yao, Wang, Jun, Li, Zhou, Li, Lianjie, Yang, Ming, and Jiang, Zhengyi
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STAINLESS steel ,TITANIUM dioxide ,GRAPHENE ,LUBRICATION & lubricants ,ALUMINUM foil - Abstract
In recent years, the quest for effective lubrication in micro deep drawing (MDD) has seen promising advancements. In this study, the influence of TiO
2 nanolubricants and graphene lubricants on the performance of 301 stainless steel foil in MDD is examined. The MDD undergoes an extensive evaluation of various lubrication conditions, including dry, TiO2 nanolubricant, graphene lubricant at concentrations of 2.5 mg/mL, 5.0 mg/mL, and 10.0 mg/mL, as well as combined applications of TiO2 and graphene lubricants. Utilising a 5.0 mg/mL graphene lubricant together with TiO2 nanolubricants led to a significant reduction in drawing force, highlighting the synergistic efficacy of this combined lubricant. A pronounced enhancement in the consistency of the produced microcups was also attained. These results emphasise the promise of TiO2 nanolubricant and graphene lubricants in optimising the MDD process. [ABSTRACT FROM AUTHOR]- Published
- 2023
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17. Management of pneumonia in the critically ill.
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Pan, Di, Nielsen, Erik, Chung, Samuel, and Niederman, Michael S.
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- 2023
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18. Optimising Two-Stage Vacuum Heat Treatment for a High-Strength Micro-Alloyed Steel in Railway Spring Clip Application: Impact on Microstructure and Mechanical Performance.
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Lu, Yao, Wang, Jun, Pan, Di, Han, Jian, Zhu, Lisong, Diao, Chenglei, Han, Jingtao, and Jiang, Zhengyi
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HEAT treatment ,SPRING ,FATIGUE limit ,IMPACT (Mechanics) ,HIGH speed trains - Abstract
The heat treatment process is a vital step for manufacturing high-speed railway spring fasteners. In this study, orthogonal experiments were carried out to obtain reliable optimised heat treatment parameters through a streamlined number of experiments. Results revealed that a better comprehensive mechanical performance could be obtained under the following combination of heat treatment parameters: quenching temperature of 850 °C, holding time of 35 min, medium of 12% polyalkylene glycol (PAG) aqueous solution, tempering temperature of 460 °C, and holding time of 60 min. As one of the most important testing criteria, fatigue performance would be improved with increasing strength. Additionally, a high ratio of martensite to ferrite is proven to improve the fatigue limit more significantly. After this heat treatment process, the metallographic microstructure and mechanical properties satisfy the technical requirements for the high-speed railway practical operation. These findings provide a valuable reference for the practical forming process of spring fasteners. [ABSTRACT FROM AUTHOR]
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- 2023
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19. Alloying promotion of Pd-based metallenes in electrocatalytic hydrogenation of functionalized nitroarenes.
- Author
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Zhang, Wenbiao, Zhang, Wanling, Tan, Jingwen, Pan, Di, Tang, Yi, and Gao, Qingsheng
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Electrocatalytic hydrogenation (ECH) provides a controllable and sustainable reduction of organic compounds via multi-electron-transfer processes under ambient conditions, which urgently demands high-performance electrocatalysts with satisfactory activity and selectivity. Here, two-dimensional Pd-based metallenes are for the first time introduced as efficient electrocatalysts for the ECH of nitroarenes, showing the intrinsic promotion of active sites by alloying effects. Thereinto, a Pd–Mo metallene with a highly exposed active surface and strong electronic interactions between Pd and Mo atoms affords the chemoselective hydrogenation of 4-nitrostyrene (4-NS) toward value-added 4-vinylaniline (4-VA). At −0.25 V vs. RHE, it reaches a high selectivity (>90.0%) and faradaic efficiency (78.3%) of 4-VA, outperforming the counterparts of a home-made Pd metallene and commercial Pd/C. The consistent alloying promotion is further verified on a series of Pd–M (M = Cr, Mo, and W) metallenes, with the specific activity sequence (Pd–Mo > Pd–W > Pd–Cr > Pd) that can be theoretically interpreted by the gradually strengthened chemisorption of 4-NS after alloying Pd with M. Moreover, the good efficiency within a broad substrate scope highlights the promise of Pd-based metallenes in electrochemical refinery. [ABSTRACT FROM AUTHOR]
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- 2023
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20. Analysis of TiO 2 Nanolubricant Influence in Micro Deep Drawing of Stainless Steel SUS301.
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Pan, Di, Zhang, Guangqing, Jia, Fanghui, Li, Lianjie, Zhang, Tao, Lu, Yao, Wu, Hui, Yang, Ming, and Jiang, Zhengyi
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LUBRICATION & lubricants ,STAINLESS steel ,AUSTENITIC stainless steel ,TITANIUM dioxide ,SURFACE roughness - Abstract
To improve the quality of products produced from microforming, various nanolubricants have been applied in the field of micromanufacturing in recent years. In this paper, the effects of glycerol-based lubricant containing TiO
2 NPs (NPs) on micro deep drawing (MDD) of austenitic stainless steel (ASS) SUS301 were studied, and the lubrication mechanism involved was discussed. The MDD experiments were conducted with the SUS301 foils under dry, 1, 2, and 4 wt% TiO2 NP lubrication conditions. The results show that the use of the TiO2 nanolubricants can significantly improve the quality of the drawn cups in terms of decreased wrinkling and surface roughness. Besides, the concentration of TiO2 NPs influences lubricity by reducing friction during the MDD process. The peak drawing force is the lowest when 2 wt% nanolubricant is applied, which drops to 72.54 N from 77.38 N under dry conditions. The micro cup drawn under 2 wt% TiO2 nanolubricant has the best quality among those obtained under all the lubrication conditions. The lubrication mechanisms are derived from the mending effects of TiO2 NPs and the formation of thin lubricant films associated with the open lubricant pockets (OLPs) and close lubricant pocket (CLPs) theory in the MDD. The CLPs function as reservoirs that retain lubricants to counteract the load pressure, whereas the OLPs lead to lubricant leakage due to the higher flow resistance. It was found that the lubricant film and NPs are insufficient at a low concentration (1 wt%), while the lubrication performance can be enhanced with increased NP concentration. However, there exist apparent agglomerations on the surface of the produced micro cup when using 4 wt% nanolubricant, which greatly deteriorates the lubricant performance in the MDD process. It is concluded that the lubricant containing 2 wt% TiO2 NPs demonstrates the best lubrication performance during the MDD of ASS SUS301. [ABSTRACT FROM AUTHOR]- Published
- 2023
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21. Carbon price forecasting based on news text mining considering investor attention.
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Pan, Di, Zhang, Chen, Zhu, Dandan, and Hu, Shu
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MARKET sentiment ,CARBON pricing ,TEXT mining ,CARBON nanofibers ,FORECASTING ,CARBON emissions ,ECONOMIC uncertainty - Abstract
The carbon market relies on market-oriented financial means to solve the problem of carbon emissions. An effective carbon pricing mechanism can improve market efficiency and better serve the implementation of carbon emission reduction. The limited attention of investors increases the uncertainty of carbon market volatility and is an important exogenous factor affecting the price of carbon assets. This study innovatively mines keywords of investor attention on the carbon market through online news texts and eliminates those that have no causal link to carbon price forecasting in order to reduce noise. The results show that the keyword extraction method based on news text mining is better than that of nontext mining. Meanwhile, a carbon price forecasting model based on a particle-swarm-optimization LSTM model structure is constructed, and the forecasting accuracy is improved. The results show that carbon market investors pay more attention to carbon quota supply and demand, carbon prices, environmental change, and the energy market. The results have important implications for the development of effective carbon market policies and risk management. [ABSTRACT FROM AUTHOR]
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- 2023
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22. Effect of different helmets against ground impact based on the in-depth reconstruction of electric two-wheeler accidents.
- Author
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Han, Yong, He, Yong, Pan, Di, Lin, Liya, Chen, Yisheng, and Feng, Hao
- Subjects
HELMETS ,ELECTRICAL injuries ,ANGULAR acceleration ,MULTIBODY systems ,SKULL fractures ,HEAD injuries - Abstract
Skull fracture and brain injury are frequent head injuries in electric two-wheeler (ETW) accidents, and the type of helmet and impact conditions affect the effectiveness of the helmet in protecting the rider's head. The purpose of this study was to conduct in-depth reconstructions of rider's head-to-ground impacts in ten ETW accidents by using a multi-body system combined with a finite element approach and to evaluate the effect of two typical full-face helmets (FFH) and one half-coverage helmet (HCH) through head accelerations and intracranial biomechanics injury metrics in ground impacts. The results showed that all three helmets reduced the risk of skull fracture in most cases, however, FFH performed better due to its wider protection area. In addition, three helmets showed varying degrees of overall reduction in measuring all indicators of brain injury. Although the effectiveness of the helmets on angular acceleration was largely influenced by the angle and location of impact, it was certain that wearing an FFH was more likely to reduce rotational head movements than an HCH, and that the FFH also offered the better advantage in reducing diffuse axonal injury (DAI) risk due to its better resistance to ejection in a crash. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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23. Characterization of a Gliding Arc Igniter from an Equilibrium Stage to a Non–Equilibrium Stage Using a Coupled 3D–0D Approach.
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Li, Zhenyang, Zhu, Yifei, Pan, Di, and Cheng, Xinyao
- Subjects
EQUILIBRIUM ,PLASMA arcs ,PLASMA sources ,INERTIAL confinement fusion ,ARC length ,COMPUTER simulation - Abstract
A gliding arc plasma source designed for high efficient ignition has been studied with the help of numerical simulation and experiments. A coupled 3D–0D approach has been proposed to model the gliding arc from ignition (the equilibrium stage) to extinguish (the non–equilibrium stage). The model takes the measured discharge morphology, voltage, current, and velocity as inputs, and has been validated by comparing the calculated temperature with experimental results from an independent group. The temporal evolution of the temperature as well as active species, and the effective penetration length of the gliding arc has been studied; the influence of the gliding arc-based plasma igniter on the ignition delay time of a premixed pentane-air gas has also been theoretically analyzed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
24. The difference in the kinematic and injury risk of cyclists between normal and emergency avoidance postures in vehicle collisions.
- Author
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Wu, He, Han, Yong, Wang, Bingyu, Pan, Di, Jin, Qianqian, Huang, Hongwu, and Mizuno, Koji
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LEG injuries ,CYCLING accidents ,HELMETS ,LINEAR acceleration ,POSTURE ,BENDING stresses ,ANGULAR acceleration - Abstract
To investigate the global kinematic differences between normal and emergency avoidance postures of cyclists at different crash speeds and the risk of head and lower extremity injuries during vehicle crashes. Seven postures (three normal and four emergency avoidance postures) were selected based on video information from 200 bicycle accidents in the VRU-Traffic Accident Video (VRU-TRAVi) database. Fourteen simulations were performed using the Total Human Safety Model (THUMS) 4.0 occupant model considering the seven postures and two-vehicle impact speeds (20 and 40 km/h). The global kinematics of the cyclists, as well as head injury parameters such as peak linear acceleration, head injury criterion (HIC), peak angular acceleration, brain injury criterion (BRIC), maximum principal strain (MPS), cumulative strain damage measure (CSDM), and lower extremity injury parameters such as von Mises stress and bending moment were calculated to assess the risk of head and lower extremity injury. The results showed that the moment of head contact with the vehicle was earlier and the slip distance of the pelvis was shorter in the emergency avoidance postures compared to the normal posture at vehicle speeds of 20 km/h and 40 km/h, which reduced the head wrap-around distance (WAD) and increased the head impact velocity. In addition, the emergency avoidance postures did not significantly reduce the risk of head injury compared to the normal posture; instead, they increased the risk of injury to the lower extremities. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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25. Kavalactones isolated from Alpinia zerumbet (Pers.) Burtt. et Smith with protective effects against human umbilical vein endothelial cell damage induced by high glucose.
- Author
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You, Hualin, He, Min, Pan, Di, Fang, Guanqin, Chen, Yan, Zhang, Xu, Shen, Xiangchun, and Zhang, Nenling
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UMBILICAL veins ,ENDOTHELIAL cells ,ALPINIA ,GLUCOSE ,CELL survival - Abstract
A new kavalactone, 4'-hydroxyl dihydro-5, 6-dehydrokavain (1) was isolated from the petroleum ether partition of leaves of Alpinia zerumbet (Pers.) Burtt. et Smith, together with four known kavalactone dimers, rel-1,trans-3-bis-(4-methoxy-2-oxopyran-6-yl)-cis-2,trans-4-diphenyl cyclobutene (2), aniba dimer A (3), aniba dimer C (4), 6,6'-(3,4-diphenylcyclobutane-1,2-diyl)bis(4-methoxy-2H-pyran-2-one (5). The structure of compound 1 was characterized by its MS, 1D-NMR, and 2D-NMR data, and the structures of the known compounds were determined by comparison of their spectroscopic data with those reported by the literatures. The obtained compounds were evaluated for their protective activities on human umbilical vein endothelial cells (HUVECs) damaged by high glucose (35 mM, cell viability at 70.10%). Compounds 3 and 5 could increase the cell viability at the concentration of 12.5 μΜ (83.12%) and 25 μΜ (75.02%), whereas at the concentration of 12.5 μΜ, compounds 1, 2, and 4 didn't reverse cell damage (cell viability at 38.58%, 54.80% and 58.16%). [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
26. Can emergency avoidance behavior reduce injuries to electric two-wheeler riders in vehicle collisions?
- Author
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Pan, Di, Han, Yong, Wu, He, Lin, Liya, Wang, Bingyu, and Huang, Hongwu
- Subjects
ELECTRICAL injuries ,LEG injuries ,HELMETS ,KNEE joint ,CRUCIATE ligaments ,MOTORCYCLING accidents ,HEAD injuries ,ANKLE ,TRAFFIC safety ,RESEARCH ,EVALUATION research ,LEARNING ,COMPARATIVE studies ,KINEMATICS - Abstract
Objectives: The aim of this study was to examine the effects of emergency avoidance behaviors on the kinematics and injuries of electric two-wheeler (ETW) riders.Methods: Four typical riding postures of ETW riders before collisions, including one normal posture and three avoidance postures, were identified through analysis of 298 videos of vehicle to ETW accidents. Crash simulations were then performed using the Total Human Model of Safety (THUMS) occupant model, ETW and a sedan finite element (FE) model, and the kinematics of ETW riders were compared. The risk of head injury and lower extremity injury was also investigated.Results: When the struck foot position of the ETW rider was lower than the ETW pedal, the lower extremity was struck by the sedan bumper and ETW frame from the right and left side respectively, and the upper body of the rider rotated around the hood leading edge. At a car velocity of 40 km/h, the rider was at high risk of head injury and the tibia was fractured. The medial cruciate ligament (MCL) was ruptured in both the 20 km/h and 40 km/h collisions. When the struck foot position of the ETW rider was higher than the pedal, the lower extremity was hit by the bumper and then rebounded. In this situation, the bending moments of the femur and tibia, as well as the bending angle and shear displacement of the knee joint were less than the injury threshold in all crash simulations. Furthermore, when the head was turned toward the colliding car, the risk of head injury varied with the emergency avoidance posture.Conclusions: The height of the struck foot relative to the ETW pedal influenced the rider's global kinematics, and head and lower extremity injuries risk. In the struck side foot landing and both feet landing postures, the lower extremity was restrained and compressed by the ETW frame, resulting in a high risk of tibia fracture and MCL rupture. Reducing the impact velocities could effectively mitigate the injury risk of the ETW riders; however, loading patterns remain an important factor influencing the risk of lower extremity injury. [ABSTRACT FROM AUTHOR]- Published
- 2022
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- View/download PDF
27. Effect of Oily Aerosol Charge Characteristics on the Filtration Efficiency of an Electrostatically Enhanced Fibrous Filter System.
- Author
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Yu, Yi, Pan, Di, Kang, Kai, Bai, Shu-Pei, Han, Hao, Song, Hua, and Kang, Jian
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FILTERS & filtration ,AEROSOLS ,ELECTRIC filters ,ELECTRIC fields ,ELECTROSTATIC precipitation ,TROPOSPHERIC aerosols - Abstract
The synergistic effect of electrostatically enhanced fibrous filtration originates from the charging characteristics of aerosol particles and electret fibers in an electric field. Two electrostatically enhanced fibrous filter systems are designed in this study to investigate the mechanism of the effects of the charging characteristics of oily aerosol on the filtration efficiency. We investigate the charging characteristics and their effects on the filtration efficiency of dioctyl-phthalate (DOP) aerosol particles of various sizes by setting different filter systems and electric field intensities. The experimental results show that the charge of DOP particles increases with the strength of the electric field, and the average charge increases with the particle size. The maximum charge of DOP particles reaches 4760 eC/P, and the filtration efficiency of the coupled system improves when DOP particles are amply charged. For 0.25 μm DOP particles as the most penetrating particle size, the system had good long-term stability, and the filtration efficiency is approximately 72% higher than that of the fiber acting alone. Meanwhile, the problem of oily aerosol deposition reducing the electret filtration efficiency is solved, providing a basis for long-term filtration and oily aerosol purification by electret fiber. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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28. c-Axis-penetrated mesoporous MWW zeolite nanosheets: preparation by H2O2-induced micro-explosion and their enhanced properties.
- Author
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Zhang, Chunna, Lin, Feng, Kong, Lingtao, Ye, Zhaoqi, Pan, Di, Li, Hongbin, Li, He, Liu, Peng, Zhang, Yahong, Zhang, Hongbin, and Tang, Yi
- Published
- 2022
- Full Text
- View/download PDF
29. Influence of intermediate roll shifting on strip shape in a CVC-6 tandem cold mill based on a 3D multi-stand FE model.
- Author
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Li, Lianjie, Xie, Haibo, Zhang, Tao, Pan, Di, Li, Xingsheng, Chen, Fenghua, Liu, Tianwu, Liu, Xu, Liu, Hongqiang, Sun, Li, and Jiang, Zhengyi
- Subjects
COLD rolling ,DISTRIBUTION (Probability theory) ,GAUSSIAN distribution - Abstract
Intermediate roll shifting (IRS) is widely used for improving the strip shape in the six-high tandem cold mill, but most related studies are limited to a single stand. To fill the knowledge gap, a three-dimensional (3D) multi-stand elastic–plastic finite element (FE) model was developed for a continuously variable crown (CVC)-6 tandem cold mill using data transfer, which was then validated by industrial experimental results. Based on this FE model, the effects of the IRS on the strip crown, strip flatness, loaded roll gap profile and contact normal stress between rolls at each stand were quantitatively analysed. The results show that from Stand 1 (S1) to Stand 5 (S5), the regulation ability of the IRS on the strip crown shows a decreasing trend, which depends on the strip plastic rigidity; in contrast, the regulation ability on the quadratic flatness experiences an obvious increase from S1 to Stand 4 (S4), then a drop at S5, while the IRS exerts little effect on the quartic flatness and quartic crown of the loaded roll gap. Moreover, the most uniform distribution of contact normal stress emerges at different IRSs from S1 to S5. These findings can contribute to a better understanding of the role of the IRS in controlling the strip shape during tandem cold rolling (TCR). [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
30. Numerical Analysis of the Effect of Work Roll Bending on Strip Crown During Tandem Hot Rolling.
- Author
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Li, Lianjie, Xie, Haibo, Li, Xingsheng, Zhang, Tao, Pan, Di, Huo, Mingshuai, Chen, Fenghua, Liu, Tianwu, Shi, Kexin, and Jiang, Zhengyi
- Subjects
HOT rolling ,NUMERICAL analysis ,COLD rolling ,HIGH strength steel ,COULOMB friction ,STRAIN rate - Published
- 2022
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31. Sepsis subphenotyping based on organ dysfunction trajectory.
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Xu, Zhenxing, Mao, Chengsheng, Su, Chang, Zhang, Hao, Siempos, Ilias, Torres, Lisa K., Pan, Di, Luo, Yuan, Schenck, Edward J., and Wang, Fei
- Abstract
Background: Sepsis is a heterogeneous syndrome, and the identification of clinical subphenotypes is essential. Although organ dysfunction is a defining element of sepsis, subphenotypes of differential trajectory are not well studied. We sought to identify distinct Sequential Organ Failure Assessment (SOFA) score trajectory-based subphenotypes in sepsis.Methods: We created 72-h SOFA score trajectories in patients with sepsis from four diverse intensive care unit (ICU) cohorts. We then used dynamic time warping (DTW) to compute heterogeneous SOFA trajectory similarities and hierarchical agglomerative clustering (HAC) to identify trajectory-based subphenotypes. Patient characteristics were compared between subphenotypes and a random forest model was developed to predict subphenotype membership at 6 and 24 h after being admitted to the ICU. The model was tested on three validation cohorts. Sensitivity analyses were performed with alternative clustering methodologies.Results: A total of 4678, 3665, 12,282, and 4804 unique sepsis patients were included in development and three validation cohorts, respectively. Four subphenotypes were identified in the development cohort: Rapidly Worsening (n = 612, 13.1%), Delayed Worsening (n = 960, 20.5%), Rapidly Improving (n = 1932, 41.3%), and Delayed Improving (n = 1174, 25.1%). Baseline characteristics, including the pattern of organ dysfunction, varied between subphenotypes. Rapidly Worsening was defined by a higher comorbidity burden, acidosis, and visceral organ dysfunction. Rapidly Improving was defined by vasopressor use without acidosis. Outcomes differed across the subphenotypes, Rapidly Worsening had the highest in-hospital mortality (28.3%, P-value < 0.001), despite a lower SOFA (mean: 4.5) at ICU admission compared to Rapidly Improving (mortality:5.5%, mean SOFA: 5.5). An overall prediction accuracy of 0.78 (95% CI, [0.77, 0.8]) was obtained at 6 h after ICU admission, which increased to 0.87 (95% CI, [0.86, 0.88]) at 24 h. Similar subphenotypes were replicated in three validation cohorts. The majority of patients with sepsis have an improving phenotype with a lower mortality risk; however, they make up over 20% of all deaths due to their larger numbers.Conclusions: Four novel, clinically-defined, trajectory-based sepsis subphenotypes were identified and validated. Identifying trajectory-based subphenotypes has immediate implications for the powering and predictive enrichment of clinical trials. Understanding the pathophysiology of these differential trajectories may reveal unanticipated therapeutic targets and identify more precise populations and endpoints for clinical trials. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
32. The relationship between prostatic microvessel density and different concentrations of oestrogen/androgen in Sprague-Dawley rats.
- Author
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Wang, Bo, Pan, Di, Ban, Yong, Sun, Zhaolin, Tian, Ye, and Luo, Guangheng
- Subjects
BLOOD coagulation factor VIII antibodies ,SPRAGUE Dawley rats ,ESTROGEN ,ANDROGENS - Abstract
Background: Currently, there are relatively few studies on the effects of changes in oestrogen and androgen levels on prostatic microvessel density (MVD). This article aimed to study the changes in prostatic MVD in Sprague-Dawley (SD) rats after castration under the effect of oestrogen/androgen at different concentrations. Methods: Male SD rats aged 3–4 months were randomly divided into a control group, a castration group, and groups with different concentrations of oestrogen/androgen treatment after castration. Dihydrotestosterone (DHT) and oestradiol (E) were administered daily by subcutaneous injection for one month. All the rats were killed by cervical dislocation after one month, and the serum DHT and E concentrations of the rats in each group were measured by ELISA. Prostate tissue specimens were immunohistochemically stained with monoclonal antibodies against CD34 and factor VIII for MVD. Results: Compared with the control group, the MVD decreased significantly in the castration group (P < 0.05). When the exogenous E concentration was constant, in general, the MVD of rats in all the groups increased with increasing exogenous DHT concentration. Compared with the castration group, the MVD increased significantly in the E0.05 + DHT0.015 mg/kg, E0.05 + DHT0.05 mg/kg, E0.05 + DHT0.15 mg/kg, E0.05 + DHT0.5 mg/kg, and E0.05 + DHT1.5 mg/kg groups (P < 0.05). In addition, when the exogenous DHT concentration was constant, the MVD increased with increasing exogenous E concentration in all the groups. Among them, compared with the control and castration groups, the MVD increased significantly in the DHT0.15 + E0.015 mg/kg, DHT0.15 + E0.15 mg/kg, and DHT0.15 + E0.5 mg/kg groups (P < 0.05). Conclusions: Androgens play an important role in the regulation of prostatic MVD in SD rats, and a decrease in DHT concentration can induce a decrease in prostatic MVD. In contrast, prostatic MVD can be increased with increasing DHT concentration. In addition, prostatic MVD can be increased gradually with increasing oestrogen concentration. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
33. The relationship between prostatic microvessel density and different concentrations of oestrogen/androgen in Sprague-Dawley rats.
- Author
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Wang, Bo, Pan, Di, Ban, Yong, Sun, Zhaolin, Tian, Ye, and Luo, Guangheng
- Abstract
Background: Currently, there are relatively few studies on the effects of changes in oestrogen and androgen levels on prostatic microvessel density (MVD). This article aimed to study the changes in prostatic MVD in Sprague-Dawley (SD) rats after castration under the effect of oestrogen/androgen at different concentrations. Methods: Male SD rats aged 3–4 months were randomly divided into a control group, a castration group, and groups with different concentrations of oestrogen/androgen treatment after castration. Dihydrotestosterone (DHT) and oestradiol (E) were administered daily by subcutaneous injection for one month. All the rats were killed by cervical dislocation after one month, and the serum DHT and E concentrations of the rats in each group were measured by ELISA. Prostate tissue specimens were immunohistochemically stained with monoclonal antibodies against CD34 and factor VIII for MVD. Results: Compared with the control group, the MVD decreased significantly in the castration group (P < 0.05). When the exogenous E concentration was constant, in general, the MVD of rats in all the groups increased with increasing exogenous DHT concentration. Compared with the castration group, the MVD increased significantly in the E0.05 + DHT0.015 mg/kg, E0.05 + DHT0.05 mg/kg, E0.05 + DHT0.15 mg/kg, E0.05 + DHT0.5 mg/kg, and E0.05 + DHT1.5 mg/kg groups (P < 0.05). In addition, when the exogenous DHT concentration was constant, the MVD increased with increasing exogenous E concentration in all the groups. Among them, compared with the control and castration groups, the MVD increased significantly in the DHT0.15 + E0.015 mg/kg, DHT0.15 + E0.15 mg/kg, and DHT0.15 + E0.5 mg/kg groups (P < 0.05). Conclusions: Androgens play an important role in the regulation of prostatic MVD in SD rats, and a decrease in DHT concentration can induce a decrease in prostatic MVD. In contrast, prostatic MVD can be increased with increasing DHT concentration. In addition, prostatic MVD can be increased gradually with increasing oestrogen concentration. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
34. Carboxymethyl Chitosan Modified Oxymatrine Liposomes for the Alleviation of Emphysema in Mice via Pulmonary Administration.
- Author
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Peng, Jianqing, Cai, Zimin, Wang, Qin, Zhou, Jia, Xu, Jinzhuan, Pan, Di, Chen, Tingting, Zhang, Guangqiong, Tao, Ling, Chen, Yi, and Shen, Xiangchun
- Subjects
CHITOSAN ,PULMONARY emphysema ,LIPOSOMES ,THERAPEUTICS ,LUNG diseases ,ANIMAL disease models - Abstract
Pulmonary emphysema is a fatal lung disease caused by the progressive thinning, enlargement and destruction of alveoli that is closely related to inflammation and oxidative stress. Oxymatrine (OMT), as a bioactive constituent of traditional Chinese herbal Sophora flavescens, has great potential to alleviate pulmonary emphysema via its anti-inflammatory and antioxidative activities. Pulmonary administration is the most preferable way for the treatment of lung diseases. To improve the in vivo stability and pulmonary retention of OMT, OMT-loaded liposome with carboxymethyl chitosan (CMCS) modification was developed. The CMCS was modified on the surface of OMT liposomes via electrostatic attraction and covalent conjugation to obtain Lipo/OMT@CMCS and CMCS-Lipo/OMT, respectively. A porcine pancreatic elastase (PPE)-induced emphysema mice model was established to evaluate the alleviation effects of OMT on alveolar expansion and destruction. CMCS-modified liposomal OMT exhibited superior ameliorative effects on emphysema regardless of the preparation methods, and higher sedimentation and longer retention in the lung were observed in the CMCS-Lipo group. The mechanisms of OMT on emphysema were related to the downregulation of inflammatory cytokines and the rebalancing of antioxidant/oxidation via the Nrf2/HO-1 and NF-κB/IκB-α signaling pathways, leading to reduced cell apoptosis. Moreover, the OMT liposomal preparations further enhanced its anti-inflammatory and antioxidative effects. In conclusion, pulmonary administration of OMT is a potential strategy for the treatment of emphysema and the therapeutic effects can be further improved by CMCS-modified liposomes. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
35. One-pot two-step process directly converting biomass-derived carbohydrate to lactide.
- Author
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Gao, Lou, Du, Ke, Yan, Tianlan, Li, He, Pan, Di, Zhang, Yahong, and Tang, Yi
- Subjects
TARTARIC acid ,LACTIC acid ,CARBOHYDRATES ,ZEOLITES - Abstract
This study proposed a strategy for the production of lactide from biomass-derived carbohydrate with excellent yield, involving sugar to racemic lactic acid conversion over Sn-containing Beta zeolite and racemic lactic acid to lactide conversion over H-Beta zeolite. Structural characteristics of the resulting lactide and extensive applicability for various substrates are also presented. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
36. Risk Factors and Algorithms for the Empirical Treatment of Hospital-Acquired Pneumonia and Ventilator-Associated Pneumonia.
- Author
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Pan, Di and Niederman, Michael S.
- Abstract
Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) continue to be major concerns for morbidity and mortality, especially in patients treated in the intensive care unit. With the rise in multidrug-resistant organisms, HAP and VAP treatment is challenged by the need for early appropriate treatment, with broad-spectrum agents, while still being aware of the principles of antibiotic stewardship. The two major society guidelines proposed a series of risk factors in their most recent guidelines to help identify patients who can most benefit from narrow- or broad-spectrum initial empiric antibiotic therapy. The guidelines reveal differences in the proposed risk factors and treatment approaches, as well as major similarities. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
37. Effect of vehicle steering maneuvers on kinematics and head injury risks of cyclists via finite element modeling analysis.
- Author
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Pan, Di, Han, Yong, He, Wei, and Huang, Hongwu
- Subjects
FINITE element method ,HEAD injuries ,ANGULAR velocity ,STEERING gear ,KINEMATICS ,CYCLISTS - Abstract
The objective of this study was to investigate the effect of a striking vehicle steering maneuvers on the kinematics and head injury risk of cyclists using the finite element (FE) modeling method. Twenty-six accident cases with video records were analyzed to define the range of the striking vehicle yaw angular velocity just before the collisions by the vehicle occurred. Parametric studies of the vehicle steering maneuvers were conducted by FE simulations using the Total Human Model of Safety (THUMS) occupant (ver. 4.0) and bicycle models at four vehicle yaw angular velocities (0, 1, 1.5 and 2 rad/s) and five impact locations (−400, −200, 0, 200 and 400 mm relative to the striking vehicle centerline). The cyclists' kinematics and head impact conditions, as well as the injury parameters of the HIC and CSDM were calculated to assess the head injury risks. The results show that the vehicle yaw angular velocities could affect the head wrap around distances (WADs) and head impact locations, as well as the head impact conditions. The Head Injury Criterion (HIC) and cumulative strain damage measure (CSDM) were higher with vehicle yaw angular velocities in most cases. That outcome could predict a higher brain injury risk compared to results without a steering maneuver. The research illustrates that the vehicle steering maneuvers could influence the cyclist head injury risk and provides basic theoretical knowledge for preventing the cyclists' injury risk. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
38. MULTIFRACTAL CROSS-CORRELATION ANALYSIS BETWEEN CARBON SPOT AND FUTURES MARKETS CONSIDERING ASYMMETRIC CONDUCTION EFFECT.
- Author
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ZHU, DANDAN, ZHANG, CHEN, PAN, DI, and HU, SHU
- Subjects
FUTURES market ,HILBERT-Huang transform ,CARBON analysis ,CARBON nanofibers - Abstract
The cross-correlation between carbon spot and futures markets reflects the risk conduction mechanism between the two markets. Deeply depicting and analyzing this risk conduction mechanism is of great significance for investors to carry out risk management strategies. Considering the nonlinear and asymmetric characteristics of cross-correlation between carbon spot and futures markets, this paper applies multifractal cross-correlation analysis method to investigate the cross-correlation between carbon spot and futures markets. Firstly, through Empirical Mode Decomposition (EMD)-Multifractal Detrended Cross-Correlation Analysis (MF-DCCA) detection, it is found that there is an obvious cross-correlation between carbon spot and futures markets, and the cross-correlation has multifractal characteristic. Secondly, by using EMD-time delay-DCCA method, we find the conduction direction between carbon spot and futures markets is bidirectional, and the futures market has a greater impact on the spot market in the short term. Thirdly, through using EMD-MF-ADCCA method, we find the cross-correlation between the two markets is asymmetric, and the cross-correlation between the two markets is more significant when carbon market is in a downward trend than in an upward trend. Fourthly, through constructing EMD-time delay-ADCCA model, we find that there is a two-way asymmetric conduction effect between carbon spot and futures markets when the lag period is short, and when the carbon market is in a downward trend, the conduction effect between the two markets is stronger. However, with the extension of time lag, the conduction effect of the two markets no longer presents obvious asymmetric characteristics. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
39. Validation of a Chinese Version of the Acquired Capability for Suicide Scale.
- Author
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Yang, Li, Pan, Di, Li, Zhen, and Liu, Xinchun
- Subjects
SUICIDE & psychology ,COLLEGE students ,STATISTICAL reliability ,RESEARCH evaluation ,RESEARCH methodology evaluation ,DISCRIMINANT analysis ,FEAR ,ATTITUDES toward death - Abstract
This study aimed to revise and validate a Chinese Version of the Acquired Capability for Suicide Scale (ACSS-CV). In study 1 of 395 Chinese college students, a two-factor model comprising fearlessness about death and pain tolerance achieved satisfactory model fit. In study 2 of 491 different students, the ACSS-CV had good internal consistency, test–retest reliability, convergent validity, and discriminant validity. The ACSS-CV may be considered a useful instrument for measuring the acquired capability for suicide in Chinese college students. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
40. PWM Strategy for MW-Scale “SiC+Si” ANPC Converter in Aircraft Propulsion Applications.
- Author
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He, Jiangbiao, Zhang, Di, and Pan, Di
- Subjects
INSULATED gate bipolar transistors ,HYBRID electric airplanes ,ELECTRIC inverters ,PULSE width modulation transformers ,ELECTRIC propulsion ,SILICON carbide ,VOLTAGE-frequency converters - Abstract
In this article, an improved pulsewidth modulation (PWM) strategy is introduced for three-level active neutral point clamped converters based on a hybrid configuration of silicon carbide (SiC) mosfets and silicon (Si) insulated gate bipolar transistor (IGBTs). Compared with the conventional PWM strategies in the literature, this proposed PWM strategy enables the SiC switches only to interface with small commutation loops, thus the turn-off voltage overshoots caused by the parasitic loop inductance and high di/dt are much lower. Soft switching is achieved across all the IGBTs, and the switching losses of the converter only dissipate from the SiC mosfets, leading to high efficiency of the converter. Also, with this improved PWM strategy, the conduction loss at zero voltage output of this converter is reduced due to the turn-on of two parallel conduction paths. Furthermore, this proposed PWM strategy can protect the body diodes of the SiC mosfets from conducting large load current. All these advantages with the proposed PWM strategy are experimentally verified in a megawatt-scale three-phase three-level “SiC+Si” hybrid active neutral point clamped inverter developed for electric aircraft propulsion applications. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
41. Evaluation and supervision of gene editing in context of implementation of the Biosafety Law of the People's Republic of China.
- Author
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WANG Pan-di, XIONG Xiao-juan, FU Ping, WU Gang, and LIU Fang
- Subjects
BIOSAFETY ,SUPERVISION - Abstract
On October 17, 2020, the Biosafety Law of the People's Republic of China (hereinafter referred to as the'biosafety law') passed the deliberation of the Standing Committee of the National People's Congress, and comes into force on April 15, 2021. Application safety of biotechnology is one of the main contents involved in the biosafety law. Gene editing, as a research hotspot in field of biotechnology in recent years, has attracted much attention in its safety evaluation and supervision. This paper summarized the present situation of the application of gene editing technology, compared the different national supervision of gene editing technology, discussed the significance of biosafety law to gene editing safety assessment and supervision in China, and finally proposed suggestions on how to better promote and implement the biosafety law in field of gene editing biosafety. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
42. Evaluation and supervision of gene editing in context of implementation of the Biosafety Law of the People's Republic of China.
- Author
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WANG Pan-di, XIONG Xiao-juan, FU Ping, WU Gang, and LIU Fang
- Subjects
BIOSAFETY ,SUPERVISION - Abstract
On October 17, 2020, the Biosafety Law of the People's Republic of China (hereinafter referred to as the 'biosafety law') passed the deliberation of the Standing Committee of the National People's Congress, and comes into force on April 15, 2021. Application safety of biotechnology is one of the main contents involved in the biosafety law. Gene editing, as a research hotspot in field of biotechnology in recent years, has attracted much attention in its safety evaluation and supervision. This paper summarized the present situation of the application of gene editing technology, compared the different national supervision of gene editing technology, discussed the significance of biosafety law to gene editing safety assessment and supervision in China, and finally proposed suggestions on how to better promote and implement the biosafety law in field of gene editing biosafety. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
43. Water Softening Mechanism and Strength Model for Saturated Carbonaceous Mudstone in Panzhihua Airport, China.
- Author
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Wang, Ziwen, Du, Jifang, Wu, Shuaifeng, Wei, Yingqi, Xiao, Jianzhang, Han, Wenxi, Pan, Di, and Zheng, Binbin
- Subjects
WATER softening ,CARBONACEOUS aerosols ,MUDSTONE ,WATER immersion ,INTERNAL friction ,SHEAR strength - Abstract
To identify the water softening mechanisms that caused landslides in Panzhihua Airport, China, property and saturation tests of the mudstones extracted from a representative landslide were proposed. In this paper, water saturation tests were carried out on samples of carbonaceous mudstone collected from the east side of the No. 12 landslide at the airport. A number of different analytical techniques and mechanical tests were used to determine changes in chemical composition, mineral assemblages, and mudstone structural characteristics, including shear strength, after the mudstone had been softened. Three kinds of changes caused by water and three mudstone softening stages are proposed. The results show that the water has a significant influence on the properties of the mudstone, so the stability of the mudstone in the watery period is a big threat to the upper structure. A model for water immersion mudstone strength softening is developed. The model incorporates a permeability coefficient, the hydraulic gradient, and time; the model can be used to determine the mudstone's shear strength and internal friction angle. This study provides a reference for the study of rock softened by water immersion. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
44. Water Softening Mechanism and Strength Model for Saturated Carbonaceous Mudstone in Panzhihua Airport, China.
- Author
-
Wang, Ziwen, Du, Jifang, Wu, Shuaifeng, Wei, Yingqi, Xiao, Jianzhang, Han, Wenxi, Pan, Di, and Zheng, Binbin
- Subjects
WATER softening ,CARBONACEOUS aerosols ,MUDSTONE ,WATER immersion ,INTERNAL friction ,SHEAR strength - Abstract
To identify the water softening mechanisms that caused landslides in Panzhihua Airport, China, property and saturation tests of the mudstones extracted from a representative landslide were proposed. In this paper, water saturation tests were carried out on samples of carbonaceous mudstone collected from the east side of the No. 12 landslide at the airport. A number of different analytical techniques and mechanical tests were used to determine changes in chemical composition, mineral assemblages, and mudstone structural characteristics, including shear strength, after the mudstone had been softened. Three kinds of changes caused by water and three mudstone softening stages are proposed. The results show that the water has a significant influence on the properties of the mudstone, so the stability of the mudstone in the watery period is a big threat to the upper structure. A model for water immersion mudstone strength softening is developed. The model incorporates a permeability coefficient, the hydraulic gradient, and time; the model can be used to determine the mudstone's shear strength and internal friction angle. This study provides a reference for the study of rock softened by water immersion. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
45. Effects of arsenic trioxide combined with platinum drugs in treatment of cervical cancer: A protocol for systematic review and meta-analysis of randomized controlled trials.
- Author
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Yawen Zhang, Di Pan, Haishi Yang, Jiaxin Huang, Zeyang He, Haiying Li, Daocheng Li, Zhang, Yawen, Pan, Di, Yang, Haishi, Huang, Jiaxin, He, Zeyang, Li, Haiying, and Li, Daocheng
- Published
- 2020
- Full Text
- View/download PDF
46. Helmet protective performance via reconstruction of electric two-wheeler rider's head-to-ground impact accidents.
- Author
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Han, Yong, He, Wei, Shi, Liangliang, Wu, He, Pan, Di, and Huang, Hongwu
- Subjects
HELMETS ,SAFETY hats ,SKULL fractures ,BRAIN injuries ,HEAD injuries ,ELECTRICAL injuries - Abstract
Numerous studies, including epidemiological, experimental and simulation studies, have shown that helmets can provide good protection for the two-wheeler (TW) rider's head and reduce the casualty rate due to head injuries during an accident. The objective of this current study was to evaluate the protective performance of a helmet based on in-depth accident reconstructions of electric two-wheel (ETW) rider's head-to-ground impact validated by the video information that provide clear and complete kinematics of ETW rider. Furthermore, validated finite element (FE) models of the helmet and human head were used. Three real-world accident cases (Cases A, B and C) were evaluated, in which, the riders' head were injured by ground impact after collided by the vehicles. In Case A and Case B, the helmet could effectively reduce the risk of skull fracture to 46% and 4%, respectively; whereas the risk of a skull fracture was up to 94% in Case C. In addition, the helmet can slightly reduce the risk of DAI injuries to 39% in Case C, while the risk of concussion cannot be reduced in three cases. In the violent impact condition such as in Case C, the bottoming out of the liner foam makes helmet lose effective protection against skull fracture. The connection between the shell and liner foam largely affects the helmet's protection against the brain injuries such as DAIs and concussions. The findings point out the lack of protective performance of the helmet and further provide more comprehensive guidance on the safety design of the helmet. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
47. Reactive oxygen species mediate anlotinib-induced apoptosis via activation of endoplasmic reticulum stress in pancreatic cancer.
- Author
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Yang, Liguo, Zhou, Xiaoshu, Sun, Jinrui, Lei, Qianghui, Wang, Qi, Pan, Di, Ding, Mingxing, and Ding, Yi
- Published
- 2020
- Full Text
- View/download PDF
48. The spring load adjustment method for six-axle high-power locomotives.
- Author
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Xiao, Yu-Qi and Pan, Di-Fu
- Subjects
LOCOMOTIVES ,GENETIC algorithms ,NONLINEAR equations ,ALGORITHMS ,SPRING ,ELECTRIC locomotives ,AUTOMOBILE defects - Abstract
The stability and comfort of locomotives need to be guaranteed by load adjustment technology. Considering the defects of the traditional two-step adjustment method for locomotive load distribution, including its lack of efficiency and error accumulation, a new technical approach is developed here under entire locomotive conditions, simulating the load adjustment test via the application of shimming under the treads. In the case of high-power locomotives, a complete theoretical model is established based on the classical two-suspension model. According to the difference between shimming on the treads and on primary suspension positions, a transformation matrix is established with which to describe the conversion relationship between the shim quantity on the primary supporting positions and on the treads. Considering that locomotive load regulation is a nonlinear problem characterised by nonlinearity, parametric uncertainty and multiple optimisation objectives, this paper proposes QAGA, an optimisation algorithm for entire locomotive load adjustment based on an adaptive genetic algorithm and a quantum-behaved particle swarm optimisation algorithm, to carry out simulations using data from an HXD1D-type electric locomotive. Analysis of the simulation results proves that the proposed approach can significantly improve the efficiency, accuracy and feasibility of the entire locomotive load adjustment process. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
49. Effect of High Hydrostatic Pressure (HHP) Processing on Immunoreactivity and Spatial Structure of Peanut Major Allergen Ara h 1.
- Author
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Pan, Di, Tang, Biling, Liu, Huipeng, Li, Zhenglong, Ma, Rongrong, Peng, Yajuan, Wu, Xuee, Che, Liming, He, Ning, Ling, Xueping, and Wang, Yuanpeng
- Subjects
HYDROSTATIC pressure ,ALLERGENS ,TERTIARY structure ,PEANUTS ,TIME pressure ,MOLECULAR weights - Abstract
Ara h 1 is recognized as a major peanut allergen. The effects of high hydrostatic pressure (HHP) on the immunoreactivity and structure of Ara h 1 were investigated in this study. The immunoreactivity of Ara h 1 was considerably reduced (P < 0.01) after HHP treatment (≥ 400 MPa) with the increase of pressure holding time. The maximum reduction of 74.32% was achieved at 600 MPa for 1200 s. The particle size and molecular weight of Ara h 1 increased, and the secondary/tertiary structure changed markedly. The decrease of the immunoreactivity of Ara h 1 was mainly due to the changes in conformation (especially the tertiary structure) and the formation of new multimers, resulting in the inactivation of immunoreactive sites. Results indicate that HHP technology has the potential to be applied to the preparation of hypoallergenic peanut products. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
50. A Megawatt-Scale Medium-Voltage High-Efficiency High Power Density “SiC+Si” Hybrid Three-Level ANPC Inverter for Aircraft Hybrid-Electric Propulsion Systems.
- Author
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Zhang, Di, He, Jiangbiao, and Pan, Di
- Subjects
METAL oxide semiconductor field-effect transistors ,POWER density ,PROPULSION systems ,INSULATED gate bipolar transistors ,FIELD-effect transistors ,ELECTRIC inverters ,SILICON carbide ,AIRCRAFT fuels - Abstract
A hybrid-electric propulsion system is an enabling technology to make the aircraft more fuel saving, quieter, and lower carbide emission. In this article, a megawatt (MW) scale power inverter based on a three-level active neutral-point-clamped (3L-ANPC) topology will be developed. To achieve high efficiency, the switching devices operating at carrier frequency in the power converter are configured by the emerging silicon carbide (SiC) metal–oxide–semiconductor field-effect transistors, while the conventional silicon (Si) insulated-gate bipolar transistors are selected for switches operating at the fundamental output frequency. To obtain high power density, dc bus voltage is increased from the conventional 270 V to medium voltage of 2.4 kV to reduce cable weight. Also, unlike the traditional 400 Hz dominated aircraft ac systems, the rated fundamental output frequency here is boosted to 1.4 kHz to drive the high-speed motor, which helps further to reduce the motor weight. Main hardware development and control modulation strategies are presented. Experimental results are presented to verify the performance of this MW-scale medium-voltage “SiC+Si” hybrid 3L-ANPC inverter. It is shown that the 1-MW 3L-ANPC inverter can achieve a high efficiency of 99% and a high power density of 12 kVA/kg. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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