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Astragalus extract inhibits destruction of gastric cancer cells to mesothelial cells by anti-apoptosis

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World Journal of Gastroenterology 2009年第5期15卷 570-577页

作者： Di Na Fu-Nan Liu Zhi-Feng Miao Zong-Min du hui-Mian xu Department of Oncology The First Affiliated Hospital China Medical University Shenyang 110001 Liaoning Province China

AIM： To determine the inhibitory effect of Astragalus memebranaceushas on gastric cancer cell supernatant- induced apoptosis of human peritoneal mesothelial cells. METHODS： Human peritoneal mesothelial cell （HPMC） line HMrSV5 was co-incubated with gastric cancer cell supernatant （MKN45） and/or Astragalus memebranaceushas. Morphological changes in gastric cancer cells were observed under phase-contrast microscope. Quantitative cell damage was determined by MTT assay. Apoptosis was determined under transmission electron microscope and quantified by detectinr, acridine orange/ethidium bromide-stained （AO/EB） condensed nuclei under fluorescent microscope or by flow cytometry. Expressions of Bcl-2 and Bax were evaluated with immunostaining.

关键词： Peritoneal carcinomatosis Stomachneoplasm Astragalus plant Mesothelial cell Apoptosis

Green Synthesis of Chemically Recyclable Polyesters via Dehydrogenative Copolymerization of Diols

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Chinese Journal of Polymer Science 2023年第8期41卷 1206-1214,I0006页

作者： Wei-Ming xu Yuan-Dong Yu Meng-Xiang Ma hui-du xu Rui-Qin Wang Yu-Peng Pan Ke-Qin Wu Wei-Ran Yang Chang-Guang Yao School of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China School of Resource&Environment Nanchang UniversityNanchang 330031China Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

Preparation of chemically recyclable polyesters by ring-opening polymerization(ROP)has made a considerable progress over the past few ***,this method involves cumbersome synthesis and minimal functional diversity of cyclic ***,it is of great significance to develop novel polymerization methods for direct polymerization of commercially available monomers to prepare recyclable polyesters with versatile *** present work,we report dehydrogenative copolymerization of commercialα,ω-diols to afford high molecular weight chemically recyclable aliphatic copolyesters(65.7 kg·mol^(-1))by using commercially available Milstein catalyst *** thermal properties of the obtained copolymers could be finely tuned by simply adjusting the feeding ratio of two *** incorporation of aliphatic or aromatic rings into polyester mainchain via copolymerization of 1,10-decanediol with 1,4-cyclohexanedimethanol and 1,4-benzenedimethanol could significantly improve the thermal properties of the resulting *** importantly,the obtained copolyesters were able to completely depolymerize back to original diols via hydrogenation by the same catalyst in solvent-free and mild conditions,thus offering a green and cost-effective route toward the preparation of widely used polyesters.

关键词： Chemically recyclable Dehydrogenative copolymerization Polyester Diol

An alternative 2D ICEEMDAN-based denoising method and its application in processing magnetic anomaly data

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Geodesy and Geodynamics 2024年第5期15卷 465-476页

作者： Jun xu Jinsong du Changqing Yuan School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Hubei Subsurface Multi-scale Imaging Key Laboratory China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan 430074China

due to environmental noise and human factors,magnetic data collected in the field often contain various noises and interferences that significantly affect the subsequent data processing and *** Mode Decomposition(EMD),an adaptive multiscale analysis method for nonlinear and non-stationary signals,is widely used in geophysical and geodetic data *** with traditional EMD,Improved Complete Ensemble EMD with Adaptive Noise(ICEEMDAN)is more effective in addressing the problem of mode *** on the principles of 1D ICEEMDAN,this paper presents an alternative algorithm for 2D ICEEMDAN,extending its application to two-dimensional *** effectiveness of the proposed approach is demonstrated through synthetic signal experiments,which show that the 2D ICEEMDAN exhibits a weaker mode mixing effect compared to the traditional bidimensional EMD(BEMD)***,to improve the performance of the denoising method based on 2D ICEEMDAN and preserve useful signals in high-frequency components,an improved soft thresholding technique is *** magnetic anomaly data testing indicates that our denoising method effectively preserves signal continuity and outperforms traditional soft thresholding *** validate the practical application of this improved threshold denoising method based on 2D ICEEMDAN,it is applied to ground magnetic survey data in the Yandun area of *** results demonstrate the effectiveness of the method in removing noise while retaining essential information from practical magnetic anomaly *** particular,practical applications suggest that 2D ICEEMDAN can extract trend signals more accurately than the *** conclusion,as a potential tool for multi-scale decomposition,the 2D ICEEMDAN is versatile in processing and analyzing 2D geophysical and geodetic data.

关键词： 2D ICEEMDAN Mode mixing effect Magnetic anomaly Denoising Improved soft thresholding

A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

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Journal of Palaeogeography 2024年第1期13卷 149-164页

作者： Da-Wei Lü Wen-xu du Zhi-hui Zhang Yuan Gao Tian-Tian Wang Jin-Cheng xu Ao-Cong Zhang Cheng-Shan Wang Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina School of Earth Sciences and Resources China University of GeosciencesBejing 100083China Institute of Earth Sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

Quantitative Analysis of Frosting Characteristics on the Drip Tray of A Cryogenic Valve for LNG Ships

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China Ocean Engineering 2024年第4期38卷 572-585页

作者： BAI xu CHEN Guan-yu du Yue xu Cao CHEN Jia-jing School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Cryogenic valves play a crucial role in the production and transportation of liquefied natural gas(LNG),and are primarily responsible for efficiently controlling the inflow and outflow of LNG and regulating ***,due to their operation in low-temperature and high-humidity environments,crucial components such as drip trays are susceptible to frosting,which may lead to LNG leakage,thereby causing severe safety *** this study,the user-defined function(UDF)is employed to redevelop Fluent,which integrates the frost growth model with the Eulerian multiphase flow model,to conduct a quantitative analysis of frosting on drip trays of cryogenic *** effects of environmental parameters,such as wind speed,ambient temperature,air humidity,and cold surface temperature on the growth of the frost layer were *** study reveals a limiting wind speed between 1 m/s and 2 m/*** reaching this limit speed,the growth of the frost layer reaches its maximum,and further increases in the wind speed have no significant effect on the growth of the frost ***,the influence of the change in the flow field on droplet impingement and freezing during the growth of the frost layer is considered through the coupling method of the kinematic characteristics of water droplets and the collection coefficient of water *** study identifies the influence of different parameters on the droplet impact efficiency,leading to the modification of the frost layer on the drip tray.

关键词： LNG carrier drip tray frost effective impact coefficient

Identification of missing CYP450 enzymes involved in paclitaxel biosynthesis and heterologous reconstitution of baccatin III

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Chinese Journal of Natural Medicines 2024年第4期22卷 291-292页

作者： du Jinfa LIAO Pan LU xu State Key Laboratory of Natural Medicines School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 210009China Department of Biology Hong Kong Baptist UniversityKowloon TongHong KongChina State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongHong KongChina State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs Beijing 100700China Medical Botanical Garden China Pharmaceutical UniversityNanjing 210009China

Paclitaxel,a tetracyclic diterpenoid,has garnered attention for its potent anti-cancer properties and intricate molecular structure,making it a significant target for chemical synthesis and biosynthesis[1].However,its natural sources are extremely limited,as it is derived exclusively from the bark of endangered genus Taxus plants,which contain paclitaxel in very low concentrations(0.01%−0.05%)[2-3].Recent advances in synthetic biology present promising opportunities to enhance paclitaxel levels in Taxus cell cultures or to enable the reconstitution of its production in heterologous hosts,such as yeast or tobacco(Nicotiana benthamiana).

关键词： Paclitaxel biosynthesis Baccatin III Cytochrome P450 Taxane oxetanase 1 Heterologous reconstitution

Multispectral image compression and encryption method based on tensor decomposition in wavelet domain

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High Technology Letters 2024年第3期30卷 244-251页

作者： xu Dongdong du Limin du Yunlong Electronic Information Engineering College Changchun UniversityChangchun 130022P.R.China

Multispectral image compression and encryption algorithms commonly suffer from issues such as low compression efficiency,lack of synchronization between the compression and encryption proces-ses,and degradation of intrinsic image structure.A novel approach is proposed to address these ***,a chaotic sequence is generated using the Lorenz three-dimensional chaotic mapping to initiate the encryption process,which is XORed with each spectral band of the multispectral image to complete the initial encryption of the ***,a two-dimensional lifting 9/7 wavelet transform is applied to the processed ***,a key-sensitive Arnold scrambling technique is employed on the resulting low-frequency *** effectively eliminates spatial redundancy in the multispectral image while enhancing the encryption *** optimize the compression and encryption processes further,fast Tucker decomposition is applied to the wavelet sub-band *** effectively removes both spectral redundancy and residual spatial redundancy in the multispectral ***,the core tensor and pattern matrix obtained from the decomposition are subjected to entropy encoding,and real-time chaotic encryption is implemented during the encoding process,effectively integrating compression and *** results show that the proposed algorithm is suitable for occasions with high requirements for compression and encryption,and it provides valuable insights for the de-velopment of compression and encryption in multispectral field.

关键词： multi-spectral image compression encryption Lorenz three-dimensional chaotic mapping Arnold scrambling transform fast Tucker decomposition

Density Clustering Algorithm Based on KD-Tree and Voting Rules

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Computers, Materials & Continua 2024年第5期79卷 3239-3259页

作者： hui du Zhiyuan Hu Depeng Lu Jingrui Liu The College of Computer Science and Engineering Northwest Normal UniversityLanzhou730070China

Traditional clustering algorithms often struggle to produce satisfactory results when dealing with datasets withuneven density. Additionally, they incur substantial computational costs when applied to high-dimensional datadue to calculating similarity matrices. To alleviate these issues, we employ the KD-Tree to partition the dataset andcompute the K-nearest neighbors (KNN) density for each point, thereby avoiding the computation of similaritymatrices. Moreover, we apply the rules of voting elections, treating each data point as a voter and casting a votefor the point with the highest density among its KNN. By utilizing the vote counts of each point, we develop thestrategy for classifying noise points and potential cluster centers, allowing the algorithm to identify clusters withuneven density and complex shapes. Additionally, we define the concept of “adhesive points” between two clustersto merge adjacent clusters that have similar densities. This process helps us identify the optimal number of clustersautomatically. Experimental results indicate that our algorithm not only improves the efficiency of clustering butalso increases its accuracy.

关键词： Density peaks clustering KD-Tree K-nearest neighbors voting rules

Automatic Requirement Dependency Extraction Based on Integrated Active Learning Strategies

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Machine Intelligence Research 2024年第5期21卷 993-1010页

作者： hui Guan Guorong Cai Hang xu Department of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China Key Laboratory of Industrial Intelligence Technology on Chemical Process Shenyang110142China

Since requirement dependency extraction is a cognitively challenging and error-prone task,this paper proposes an automatic requirement dependency extraction method based on integrated active learning *** this paper,the coefficient of variation method was used to determine the corresponding weight of the impact factors from three different angles:uncertainty probability,text similarity difference degree and active learning variant prediction divergence *** combining the three factors with the proposed calculation formula to measure the information value of dependency pairs,the top K dependency pairs with the highest comprehensive evaluation value are selected as the optimal *** the optimal samples are continuously added into the initial training set,the performance of the active learning model using different dependency features for requirement dependency extraction is rapidly ***,compared with other active learning strategies,a higher evaluation measure of requirement dependency extraction can be achieved by using the same number of ***,the proposed method using the PV-DM dependency feature improves the weight-F1 by 2.71%,the weight-recall by 2.45%,and the weight-precision by 2.64%in comparison with other strategies,saving approximately 46%of the labelled data compared with the machine learning approach.

关键词： Requirement dependency dependency extraction dependency features integrated active learning strategies coefficient of variation