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Dioscin from Polygonatum sibiricum induces apoptosis and autophagy in Ishikawa human endometrial cancer cell and in vivo
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作者 Xiaoli Li Runhui Ma +4 位作者 Zhijing Ni Wei Wang Kiran Thakur jianguo zhang Zhaojun Wei 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2601-2616,共16页
With an aim to comprehend the precise regulatory mechanism of dioscin against endometrial carcinoma(EC), we firstly extracted the components from Polygonatum sibiricum followed by identification and structural charact... With an aim to comprehend the precise regulatory mechanism of dioscin against endometrial carcinoma(EC), we firstly extracted the components from Polygonatum sibiricum followed by identification and structural characterization. The anti-EC activity of dioscin was initially determined based on the inhibition of Ishikawa cell proliferation and tumor growth. The high-throughput sequencing data indicated that dioscin not only promoted apoptosis, including decrease of poly ADP-ribose polymerase(PARP) and B-cell lymphoma-2(Bcl-2) and increase of c-PARP and Bcl-2-associcated agonist of cell death(Bad), but also induced autophagy, including increase of autophagic lysosomes and LC3Ⅱ/LC3Ⅰ ratio. Mechanistic exploration suggested that dioscin induced autophagy and apoptosis through inhibition of PI3K/AKT/mTOR signaling pathway. Besides, the dioscin-regulated p53 pathway was mainly involved in autophagy induction. Furthermore, inhibition of Ishikawa cell autophagy was linked to dioscin-induced apoptosis. Our data suggest the immense potential of dioscin for the development of functional food for EC and related medical application. 展开更多
关键词 DIOSCIN Ishikawa cell APOPTOSIS AUTOPHAGY PI3K/AKT p53
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Combination of Nitrogen-Rich Skeleton and Coordination Group:Synthesis of a High-Energy Primary Explosive Based on 1H-Tetrazole-5-Carbohydrazide
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作者 Tingwei Wang Zujia Lu +6 位作者 Shu Bu Baolong Kuang Lu zhang Zhenxin Yi Kun Wang Shunguan Zhu jianguo zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期271-277,共7页
The high energy coordination compounds Cu(TZCA)_(2)(ClO_(4))_(2)(ECCs-1) was prepared by 1H-tetrazole-5-carbohydrazide(TZCA) with a high energy skeleton and a strong coordination ability group.At the same time,the rea... The high energy coordination compounds Cu(TZCA)_(2)(ClO_(4))_(2)(ECCs-1) was prepared by 1H-tetrazole-5-carbohydrazide(TZCA) with a high energy skeleton and a strong coordination ability group.At the same time,the reaction activity of the ligand was explored,and the single crystal structure of it and intermediate were obtained.The structures of all substances were characterized by IR and EA.And the structure and composition of ECCs-1 are confirmed by ESP,AC,SEM and ICP-OES.Physical and chemical properties tests show that ECCs-1 has an acceptable thermal stability(T_(d)=177℃) and extremely sensitive mechanical stimulation(IS=1 J,FS=5 N).The comprehensive performance test results show that ECCs-1 has excellent initiation ability.In addition,the decomposition mechanism of ECCs-1 is explored from two aspects of experiment and theoretical calculation. 展开更多
关键词 1H-tetrazole-5-carbohydrazide Primary explosive Decomposition mechanism Coordination polymers Laser
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Field-assisted machining of difficult-to-machine materials
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作者 jianguo zhang Zhengding Zheng +5 位作者 Kai Huang Chuangting Lin Weiqi Huang Xiao Chen Junfeng Xiao Jianfeng Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期39-89,共51页
Difficult-to-machine materials (DMMs) are extensively applied in critical fields such as aviation,semiconductor,biomedicine,and other key fields due to their excellent material properties.However,traditional machining... Difficult-to-machine materials (DMMs) are extensively applied in critical fields such as aviation,semiconductor,biomedicine,and other key fields due to their excellent material properties.However,traditional machining technologies often struggle to achieve ultra-precision with DMMs resulting from poor surface quality and low processing efficiency.In recent years,field-assisted machining (FAM) technology has emerged as a new generation of machining technology based on innovative principles such as laser heating,tool vibration,magnetic magnetization,and plasma modification,providing a new solution for improving the machinability of DMMs.This technology not only addresses these limitations of traditional machining methods,but also has become a hot topic of research in the domain of ultra-precision machining of DMMs.Many new methods and principles have been introduced and investigated one after another,yet few studies have presented a comprehensive analysis and summarization.To fill this gap and understand the development trend of FAM,this study provides an important overview of FAM,covering different assisted machining methods,application effects,mechanism analysis,and equipment design.The current deficiencies and future challenges of FAM are summarized to lay the foundation for the further development of multi-field hybrid assisted and intelligent FAM technologies. 展开更多
关键词 field-assisted machining difficult-to-machine materials materials removal mechanism surface integrity
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Achieving high-security and massive-capacity optical communications based on orbital angular momentum configured chaotic laser
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作者 Yanwei Cui jianguo zhang +2 位作者 Zhongquan Nie Anbang Wang Yuncai Wang 《Advanced Photonics Nexus》 2024年第4期92-100,共9页
Secure and high-speed optical communications are of primary focus in information transmission.Although it is widely accepted that chaotic secure communication can provide superior physical layer security,it is challen... Secure and high-speed optical communications are of primary focus in information transmission.Although it is widely accepted that chaotic secure communication can provide superior physical layer security,it is challenging to meet the demand for high-speed increasing communication rate.We theoretically propose and experimentally demonstrate a conceptual paradigm for orbital angular momentum(OAM)configured chaotic laser(OAM-CCL)that allows access to high-security and massivecapacity optical communications.Combining 11 OAM modes and an all-optical feedback chaotic laser,we are able to theoretically empower a well-defined optical communication system with a total transmission capacity of 100 Gb∕s and a bit error rate below the forward error correction threshold 3.8×10^(-3).Furthermore,the OAM-CCL-based communication system is robust to 3D misalignment by resorting to appropriate mode spacing and beam waist.Finally,the conceptual paradigm of the OAM-CCL-based communication system is verified.In contrast to existing systems(traditional free-space optical communication or chaotic optical communication),the OAM-CCL-based communication system has threein-one characteristics of high security,massive capacity,and robustness.The findings demonstrate that this will promote the applicable settings of chaotic laser and provide an alternative promising route to guide high-security and massive-capacity optical communications. 展开更多
关键词 chaotic secure communication orbital angular momentum configured chaotic laser high security massive capacity MISALIGNMENT
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血细胞参数NLR和RPR预测急性ST段抬高心肌梗死的价值分析 被引量:1
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作者 张建国 王丽媛 陶然 《临床检验杂志(电子版)》 2017年第3期449-451,共3页
目的探讨血细胞参数NLR和RPR对急性ST段抬高心肌梗死(STEMI)的预测价值。方法选取急性STEMI患者110例,对照人群109例,收集这些研究对象的中性粒细胞、淋巴细胞及RDW、PLT数据,根据公式NLR=N/L,RPR=RDW(%)/PLT(109/L),计算所有研究对象的... 目的探讨血细胞参数NLR和RPR对急性ST段抬高心肌梗死(STEMI)的预测价值。方法选取急性STEMI患者110例,对照人群109例,收集这些研究对象的中性粒细胞、淋巴细胞及RDW、PLT数据,根据公式NLR=N/L,RPR=RDW(%)/PLT(109/L),计算所有研究对象的NLR和RPR。结果急性STEMI患者组和对照组人群的NLR及RPR结果比较均具有统计学差异(P<0.05)。NLR和RPR对急性STEMI患者的诊断价值大小用ROC曲线下面积(AUC)表示为0.914、0.724;当NLR的诊断最佳截点值为4.002时,灵敏度为0.809,特异度为0.543,阳性预测值为0.899,阴性预测值为0.825;当RPR的诊断最佳截点值为0.056时,灵敏度为0.800,特异度为0.578,阳性预测值为0.652,阴性预测值为0.738。结论 NLR和RPR对于急性STEMI均具有一定预测价值,但参数NLR的价值更高。 展开更多
关键词 急性ST段抬高心肌梗死 NLR RPR
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Stand basal area modelling for Chinese fir plantations using an artificial neural network model 被引量:6
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作者 Shaohui Che Xiaohong Tan +5 位作者 Congwei Xiang Jianjun Sun Xiaoyan Hu Xiongqing zhang Aiguo Duan jianguo zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第5期1641-1649,共9页
Artificial neural network models are a popular estimation tool for fitting nonlinear relationships because they require no assumptions about the form of the fitting function,non-Gaussian distributions,multicollinearit... Artificial neural network models are a popular estimation tool for fitting nonlinear relationships because they require no assumptions about the form of the fitting function,non-Gaussian distributions,multicollinearity,outliers and noise in the data.The problems of backpropagation models using artificial neural networks include determination of the structure of the network and overlearning courses.According to data from 1981 to 2008 from 15 permanent sample plots on Dagangshan Mountain in Jiangxi Province,a back-propagation artificial neural network model(BPANN)and a support vector machine model(SVM)for basal area of Chinese fir(Cunninghamia lanceolata)plantations were constructed using four kinds of prediction factors,including stand age,site index,surviving stem numbers and quadratic mean diameters.Artificial intelligence methods,especially SVM,could be effective in describing stand basal area growth of Chinese fir under different growth conditions with higher simulation precision than traditional regression models.SVM and the Chapman–Richards nonlinear mixed-effects model had less systematic bias than the BPANN. 展开更多
关键词 Chinese FIR BASAL area Artificial NEURAL network Support VECTOR MACHINE Mixed-effect model
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Chondrogenesis mediates progression of ankylosing spondylitis through heterotopic ossification 被引量:13
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作者 Tao Yu jianguo zhang +13 位作者 Wei Zhu Xiao Wang Yun Bai Bin Feng Qianyu Zhuang Chang Han Shengru Wang Qimiao Hu Senbo An Mei Wan Shiwu Dong Jianzhong Xu Xisheng Weng Xu Cao 《Bone Research》 SCIE CAS CSCD 2021年第2期166-177,共12页
Ankylosing spondylitis(AS)is chronic inflammatory arthritis with a progressive fusion of axial joints.Anti-inflammatory treatments such as anti-TNF-αantibody therapy suppress inflammation but do not effectively halt ... Ankylosing spondylitis(AS)is chronic inflammatory arthritis with a progressive fusion of axial joints.Anti-inflammatory treatments such as anti-TNF-αantibody therapy suppress inflammation but do not effectively halt the progression of spine fusion in AS patients.Here we report that the autoimmune inflammation of AS generates a microenvironment that promotes chondrogenesis in spine ligaments as the process of spine fusion.Chondrocyte differentiation was observed in the ligaments of patients with earlystage AS,and cartilage formation was followed by calcification.Moreover,a large number of giant osteoclasts were found in the inflammatory environment of ligaments and on bony surfaces of calcified cartilage.Resorption activity by these giant osteoclasts generated marrow with high levels of active TGF-β,which induced new bone formation in the ligaments.Notably,no Osterix+osteoprogenitors were found in osteoclast resorption areas,indicating uncoupled bone resorption and formation.Even at the late and maturation stages,the uncoupled osteoclast resorption in bony interspinous ligament activates TGF-βto induce the progression of ossification in AS patients.Osteoclast resorption of calcified cartilage-initiated ossification in the progression of AS is a similar pathologic process of acquired heterotopic ossification(HO).Our finding of cartilage formation in the ligaments of AS patients revealed that the pathogenesis of spinal fusion is a process of HO and explained why anti-inflammatory treatments do not slow ankylosing once there is new bone formation in spinal soft tissues.Thus,inhibition of HO formation,such as osteoclast activity,cartilage formation,or TGF-βactivity could be a potential therapy for AS. 展开更多
关键词 OSSIFICATION INFLAMMATION SPONDYLITIS
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Forest biomass carbon storage from multiple inventories over the past 30 years in Gansu Province, China: implications from the age structure of major forest types 被引量:5
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作者 Jinhong Guan Huanshui Zhou +2 位作者 Lei Deng jianguo zhang Sheng Du 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期887-896,共10页
We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979-2006. Total forest area increased from 1.77... We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979-2006. Total forest area increased from 1.77 x 106 ha in 1979 to 2.32 x 106 ha in 2006, and the forest carbon storage, estimated by the continuous biomass expansion factor method, increased from 83.14 to 100.66 Tg, equivalent to a carbon accumulation rate of 0.0071 Tg per year during the period. Mean carbon densities were 44.83-48.50 t ha-1 and the values decreased slightly over the time period. Natural forests generated greater car- bon storage and density than did plantations. By regression analysis, forest stand age was an important parameter incarbon density studies. We developed various regression equations between carbon density and stand age for major types of natural forests and plantations in the region. Our results can be used for proper selection of re-forestation species and efficient management of young and middle-aged forests, offering great potential for future carbon sequestra- tion, especially in arid and semi-arid regions. 展开更多
关键词 Age class Carbon density Forest carbonstorage Forest inventory data Gansu Province REFORESTATION
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Bayesian-based information extraction and aggregation approach for multilevel systems with multi-source data 被引量:3
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作者 Lechang Yang jianguo zhang +1 位作者 Yanling Guo Qian Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期385-400,共16页
The ever-increasing complexity of industry facilities has made the reliability analysis and assessment an imperative yet tough work. Motivated by practical engineering requirement, this paper develops a Bayesian-based... The ever-increasing complexity of industry facilities has made the reliability analysis and assessment an imperative yet tough work. Motivated by practical engineering requirement, this paper develops a Bayesian-based information extraction and aggregation (BIEA) approach for system level reliability estimation of a complex system. It takes both subjective judgments and objective field outputs into consideration. Novel features of this approach is a unique information content based aggregation process, which allows a flexible application of this framework in separated modules on account for purpose. The coherency of which is guaranteed by the objective information content calculation. This work goes beyond the alternatives that deal with solely attributed data under ideal information circumstance, and investigates a more generic tool for real engineering application. Limitations embedded in traditional statistical modeling methods have been eliminated in a nature manner by information transition and integration. In addition, a double axis driving mechanism (DADM) for erecting the antenna of a satellite is demonstrated as case study for benefit illustration and effectiveness verification. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Artificial intelligence Data fusion Information analysis Information retrieval RELIABILITY Reliability analysis
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Characterization and comparison of chloroplast genomes from two sympatric Hippophae species(Elaeagnaceae) 被引量:3
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作者 Luoyun Wang Jing Wang +2 位作者 Caiyun He jianguo zhang Yanfei Zeng 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期307-318,共12页
The genus Hippophae includes deciduous shrubs or small trees,which provide many ecological,economic,and social benefi ts.We assembled and annotated the chloroplast genomes of sympatric Hippophae gyantsensis(Rousi)Lian... The genus Hippophae includes deciduous shrubs or small trees,which provide many ecological,economic,and social benefi ts.We assembled and annotated the chloroplast genomes of sympatric Hippophae gyantsensis(Rousi)Lian and Hippophae rhamnoides Linn subsp.yunnanensis Rousi and comparatively analyzed their sequences.The fulllength chloroplast genomes of H.gyantsensis and H.rhamnoides subsp.yunnanensis were 155,260 and 156,415 bp,respectively;both featured a quadripartite structure with two copies of a large inverted repeat(IR)separated by small(SSC)and large(LSC)single-copy regions.Each Hippophae chloroplast genome contained 131 genes,comprising 85 protein-coding,8 ribosomal RNA,and 38 transfer RNA genes.Of 1302 nucleotide substitutions found between these twogenomes,824(63.29%)occurred in the intergenic region or intron sequences,and 478(36.71%)were located in the coding sequences.The SSC region had the highest mutation rate,followed by the LSC region and IR regions.Among the protein-coding genes,three had a ratio of nonsynonymous to synonymous substitutions(Ka/Ks)>1 yet none were signifi-cant,and 66 had Ka/Ks<1,of which 46 were signifi cant.We found 20 and 16 optimal codons,most of which ended with A or U,for chloroplast protein-coding genes of H.gyantsensis and H.rhamnoides subsp.yunnanensis,respectively.Phylogenetic analysis of fi ve available whole chloroplast genome sequences in the family Elaeagnaceae—using one Ziziphus jujube sequence as the outgroup—revealed that all fi ve plant species formed a monophyletic clade with two subclades:one subclade consisted of three Hippophae species,while the other was formed by two Elaeagnus species,supported by 100%bootstrap values.Together,these results suggest the chloroplast genomes among Hippophae species are conserved,both in structure and gene composition,due to general purifying selection;like many other plants,a signifi cant AT preference was discerned for most proteincoding genes in the Hippophae chloroplast genome.This study provides a valuable reference tool for future research on the general characteristics and evolution of chloroplast genomes in the genus Hippophae. 展开更多
关键词 Chloroplast genome Hippophae gyantsensis(Rousi)Lian Hippophae rhamnoides Linn subsp.yunnanensis Ka/Ks Optimal codon
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Numerical simulation of materials-oriented ultra-precision diamond cutting:review and outlook 被引量:3
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作者 Liang Zhao Junjie zhang +3 位作者 jianguo zhang Houfu Dai Alexander Hartmaier Tao Sun 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第2期1-21,共21页
Ultra-precision diamond cutting is a promising machining technique for realizing ultra-smooth surface of different kinds of materials.While fundamental understanding of the impact of workpiece material properties on c... Ultra-precision diamond cutting is a promising machining technique for realizing ultra-smooth surface of different kinds of materials.While fundamental understanding of the impact of workpiece material properties on cutting mechanisms is crucial for promoting the capability of the machining technique,numerical simulation methods at different length and time scales act as important supplements to experimental investigations.In this work,we present a compact review on recent advancements in the numerical simulations of material-oriented diamond cutting,in which representative machining phenomena are systematically summarized and discussed by multiscale simulations such as molecular dynamics simulation and finite element simulation:the anisotropy cutting behavior of polycrystalline material,the thermo-mechanical coupling tool-chip friction states,the synergetic cutting responses of individual phase in composite materials,and the impact of various external energetic fields on cutting processes.In particular,the novel physics-based numerical models,which involve the high precision constitutive law associated with heterogeneous deformation behavior,the thermo-mechanical coupling algorithm associated with tool-chip friction,the configurations of individual phases in line with real microstructural characteristics of composite materials,and the integration of external energetic fields into cutting models,are highlighted.Finally,insights into the future development of advanced numerical simulation techniques for diamond cutting of advanced structured materials are also provided.The aspects reported in this review present guidelines for the numerical simulations of ultra-precision mechanical machining responses for a variety of materials. 展开更多
关键词 diamond cutting ultra-smooth surface material-oriented physics-based simulation model molecular dynamics finite element
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De novo assembly of a new Olea europaea genome accession using nano pore seque ncing 被引量:5
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作者 Guodong Rao jianguo zhang +4 位作者 Xiaoxia Liu Chunfu Lin Huaigen Xin Li Xue Chenhe Wang 《Horticulture Research》 SCIE 2021年第1期1179-1190,共12页
Olive(Olea europaea L.)is internationally renowned for its high-end product,extra virgin olive oil.An incomplete genome of O.europaea was previously obtained using shotgun sequencing in 2016.To further explore the gen... Olive(Olea europaea L.)is internationally renowned for its high-end product,extra virgin olive oil.An incomplete genome of O.europaea was previously obtained using shotgun sequencing in 2016.To further explore the genetic and breeding utilization of olive,an updated draft genome of olive was obtained using Oxford Nanopore third-generation sequencing and Hi-C technology.Seven different assembly strategies were used to assemble the fi nal genome of 1.30 Gb,with contig and scaffold N50 sizes of4.67 Mb and 42.60 Mb,respectively.This greatly increased the quality of the olive genome.We assembled 1.1 Gb of sequences of the total olive genome to 23 pseudochromosomes by Hi-C,and 53,518 protein-coding genes were predicted in the current assembly.Comparative genomics analyses,including gene family expansion and contraction,whole-genome replication,phylogenetic analysis,and positive selection,were performed.Based on the obtained high-quality olive genome,a total of nine gene families with 202 genes were identi fi ed in the oleuropein biosynthesis pathway,which is twice the number ofgenes identi fi ed from the previous data.This new accession of the olive genome is of suf fi cient quality for genome-wide studies on gene function in olive and has provided a foundation for the molecular breeding of olive species. 展开更多
关键词 BREEDING OLEA ASSEMBLY
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Novel dynamic evidential Petri net for system reliability analysis 被引量:2
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作者 Wensheng Peng jianguo zhang Jinyang zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期1019-1027,共9页
This paper proposes a novel dynamic Petri net (PN) model based on Dempster-Shafer (D-S) evidence theory, and this improved evidential Petri net (EPN) model is used in knowledge inference and reliability analysis of co... This paper proposes a novel dynamic Petri net (PN) model based on Dempster-Shafer (D-S) evidence theory, and this improved evidential Petri net (EPN) model is used in knowledge inference and reliability analysis of complex mechanical systems. The EPN could take epistemic uncertainty such as interval information, subjective information into account by applying D-S evidence quantification theory. A dynamic representation model is also proposed based on the dynamic operation rules of the EPN model, and an improved artificial bee colony (ABC) algorithm is employed to proceed optimization calculation during the complex systems' learning process. The improved ABC algorithm and D-S evidence theory overcome the disadvantage of extremely subjective in traditional knowledge inference efficiently and thus could improve the accuracy of the EPN learning model. Through a simple numerical case and a satellite driving system analysis, this paper proves the superiority of the EPN and the dynamic knowledge representation method in reliability analysis of complex systems. 展开更多
关键词 evidence theory Petri net knowledge representation improved ABC algorithm imprecise information RELIABILITY
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Transcriptome-wide effect of Salix SmSPR1 in etiolated seedling of Arabidopsis 被引量:2
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作者 Xiaoxia Liu jianguo zhang +1 位作者 Li Xue Guodong Rao 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第3期975-985,共11页
Microtubules and their regulatory proteins are involved in the regulation of plant cell morphology.SPIRAL1(SPR1),a plant-specific microtubule-binding protein,is critical in regulating the anisotropic growth of plant c... Microtubules and their regulatory proteins are involved in the regulation of plant cell morphology.SPIRAL1(SPR1),a plant-specific microtubule-binding protein,is critical in regulating the anisotropic growth of plant cells.Our previous study showed that overexpressed S alix SmS PR1 genes in Arabidopsis thaliana caused right-handed spiral elongation in etiolated seedlings,but there were no morphological differences between wild-type and transgenic seedlings under varied light conditions.We then studied the transcriptional regulation patterns in transgenic plants engineered with the S mSPR1 gene.Transcriptomic results showed that a large number of differentially expressed genes were involved in plant light signal reception,chlorophyll synthesis and photosystem structure.Eleven gene families with 42 photosynthesis-related genes and 6 light-responsive genes were involved in regulation of cell morphology.Our results showed that these genes in the SmSPR1-ox line were particularly down-regulated under dark conditions.In addition,33 TFs showed differences between S mSPR1-ox and wild-type lines.Taken together,the transcriptome analysis provides new insight into investigating the molecular mechanisms of light-induced cell morphological changes mediated by the microtubule binding protein SPR1. 展开更多
关键词 Arabidopsis thaliana Cell anisotropism SmSPR1 Transcription factor Transcriptome analysis
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Discovery of lacustrine shale deposits in the Yanshan Orogenic Belt,China: Implications for hydrocarbon exploration 被引量:2
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作者 Yuanfu zhang Xiaodong Yuan +6 位作者 Min Wang Pengcheng Ge Yancui Huo Jie Xu jianguo zhang Jian Cheng Zaixing Jiang 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期326-353,共28页
The mechanism of formation of lacustrine deposits within stable orogenic belts and their potential for shale oil and gas exploration are frontier themes of challenge in the fields of sedimentology and petroleum explor... The mechanism of formation of lacustrine deposits within stable orogenic belts and their potential for shale oil and gas exploration are frontier themes of challenge in the fields of sedimentology and petroleum exploration. Orogenic belts witness strong tectonic activities and normally cannot host stable lacustrine basins and deep shale formations. Therefore, basins in orogenic belts are considered to have no potential to form shale hydrocarbon reservoirs. Here we investigate the Luanping Basin located in the Yanshan orogenic belt where previous studies regarded rivers and fan deltas as the major main Mesozoic deposits. Based on detailed field exploration and scientific drilling, we report the finding of a large number of lacustrine shale continental deep-water deposits in the Mesozoic strata. Our finding of the occurrence of active shale oil and gas also in this basin also subvert the previous perceptions.We report SHRIMP zircon U-Pb age that define the bottom boundary of the target interval as 127.6 ± 1.7 Ma belonging to the early Cretaceous strata. Tectonics and climate are considered to be the main factors that controlled the deep-water sedimentation during this period. The drill cores revealed evidence of shale gas and the TOC of shale is 0.33%–3.60%, with an average value of 1.39% and Ro is 0.84%–1.21%, with an average value of 1.002%. The brittleness index of shale is between 52.7% and 100%. After vertical well fracturing, the daily gas production is more than 1000 m^(3). Our findings show that the basin has considerable potential for shale oil and gas. The geological resources of the shale gas in the Xiguayuan Fm. are estimated as 1110.12 × 10^(8) m^(3), with shale oil geological resources of 3340.152 × 10^(4) t. Our findings indicate that the Yanshan orogenic belt has potential exploration prospect. This work not only redefines the Luanping Basin as a rift deep-water Mesozoic Lake Basin, but also rules out the previous notion that the basin is dominated by shallow water sediments. The discovery of shale oil and gas also provides an important reference for subsequent petroleum exploration and development in this basin. Our study shows that shale oil and gas reservoirs can be found in the lacustrine basins of orogenic belts which were strongly influenced by volcanism. These results have significant implications for the sedimentology and oil exploration in the Qinling and Xingmeng Orogenic Belts of China, as well as those in other terranes of the world including the New England Orogenic Belt in Australia. 展开更多
关键词 Luanping Basin Deep-water sedimentation Drill core data Lacustrine deposits Petroleum exploration
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Strata movement and stress evolution when mining two overlapping panels affected by hard stratum 被引量:2
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作者 jianguo zhang Wei Yang +2 位作者 Baiquan Lin Jinjing zhang Man Wang 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第5期691-699,共9页
Mining causes stress redistribution and stratum movement.In this paper,a numerical model was built according to the geological conditions in the 12th coal mine in Pingdingshan city to study the strata movement and the... Mining causes stress redistribution and stratum movement.In this paper,a numerical model was built according to the geological conditions in the 12th coal mine in Pingdingshan city to study the strata movement and the evolution of stress when mining two overlapping longwall panels,named panels#14 and#15.The strata close to the mined panel move directly towards the gob,while the strata that are farther away swing back and forth during the mining process.The directed movement and swinging can break the transverse boreholes for gas extraction;a surface borehole should not be within the range of directional movement.The stress evolution suggested that the mining of the lower panel#15 after the upper panel#14 would further increase the de-stressed range,while the stress concentration around the mined panel would be increased.Hard strata usually carry a greater stress than adjacent rocks and soft coal seams.The stress in a hard stratum increases greatly,and the stress decreases greatly in the coal seams below the hard stratum.This study supplies a reference for similar coal mines and is useful for determining the de-stressed range and transverse borehole arrangement for gas extraction. 展开更多
关键词 STRATUM movement MINING LONGWALL panel HARD STRATUM
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Apigenin, a natural flavonoid, promotes autophagy and ferroptosis in human endometrial carcinoma Ishikawa cells in vitro and in vivo 被引量:2
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作者 Yancui Liang Qian Zhong +4 位作者 Runhui Ma Zhijing Ni Kiran Thakur jianguo zhang Zhaojun Wei 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期2242-2251,共10页
Apigenin,a natural flavonoid has been reported against a variety of cancer types.However,it is unclear whether apigenin can promote autophagy and ferroptosis in Ishikawa cells.There are few reports on the mechanism of... Apigenin,a natural flavonoid has been reported against a variety of cancer types.However,it is unclear whether apigenin can promote autophagy and ferroptosis in Ishikawa cells.There are few reports on the mechanism of apigenin on autophagy and ferroptosis of endometrial cancer Ishikawa cells.We found that iron accumulation,lipid peroxidation,glutathione consumption,p62,HMOX1,and ferritin were increased,while,solute carrier family 7 member 11 and glutathione peroxidase 4 were decreased.Ferrostatin-1,an iron-death inhibitor could reverse the effects of apigenin in Ishikawa cells.On the other hand,apigenin could promote autophagy via up-regulating Beclin 1,ULK1,ATG5,ATG13,and LC3B and down-regulating AMPK,mTOR,P70S6K,and ATG4.Furthermore,apigenin could inhibit tumor tissue proliferation and restrict tumor growth via ferroptosis in vivo. 展开更多
关键词 Flavonoid APIGENIN AUTOPHAGY Ferroptosis Ishikawa cells Tumor growth Endometrial carcinoma
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Site index for Chinese fir plantations varies with climatic and soil factors in southern China 被引量:1
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作者 Xiaoyan Li Aiguo Duan jianguo zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第6期1765-1780,共16页
Chinese fir[Cunninghamia lanceolata(Lamb.)Hook.]has a large native distribution range in southern China.Here,we tested differences in productivity of Chinese fir plantations in different climatic regions and screened ... Chinese fir[Cunninghamia lanceolata(Lamb.)Hook.]has a large native distribution range in southern China.Here,we tested differences in productivity of Chinese fir plantations in different climatic regions and screened the main environmental factors affecting site productivity in each region.Relationships of a Chinese fir site index with climatic factors and the soil physiochemical properties of five soil layers were examined in a long-term positioning observation trial comprising a total of 45 permanent plots in Fujian(eastern region in the middle subtropics),Guangxi(south subtropics)and Sichuan(central region in the middle subtropics)in southern China.Linear mixed effects models were developed to predict the site index for Chinese fir,which was found to vary significantly among different climatic regions.Available P,total N,bulk density and total K were dominant predictors of site index in three climatic regions.The regional linear mixed models built using these predictors in the three climatic regions fit well(R~2=0.86–0.97).For the whole study area,the available P in the 0–20-cm soil layer and total N in the 80–100-cm soil layer were the most indicative soil factors.MAP was the most important climatic variable influencing the site index.The model evaluation results showed that the fitting performance and prediction accuracy of the global site index model using the climatic region as the dummy variable and random parameters and the most important soil factors of the three climatic regions as predictors was higher than that of global site index model using the climatic variable and the most indicative soil variables of the whole study area.Our results will help with further evaluation of site quality of Chinese fir plantations and the selection of its appropriate sites in southern China as the climatic changes. 展开更多
关键词 Site productivity Site index CLIMATE SOIL Chinese fir
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Interval Motion Accuracy Reliability Analysis of Manipulators Based on Chebyshev Inclusion Polynomial 被引量:1
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作者 Juan Wei jianguo zhang Xiaosong Du 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第2期32-40,共9页
Motion accuracy of space manipulators has direct effects on the ability of the systems to perform specified tasks. However, some design variables are inherently interval parameters due to uncertainties in geometric st... Motion accuracy of space manipulators has direct effects on the ability of the systems to perform specified tasks. However, some design variables are inherently interval parameters due to uncertainties in geometric structures, material properties, and so on. This paper presents Chebyshev inclusion function(CIF) for approximating the dynamic responses function of parametrically excited systems. Motion accuracy reliability(MAR) of space manipulators was evaluated based on mechanism reliability analysis methods and interval uncertainty model. To illustrate the accuracy of the proposed method, a two-link manipulator with interval parameters was demonstrated. The results showed that the proposed method required much fewer samples to obtain more accurate reliability compared with the traditional Monte Carlo simulation(MCS). Finally, the sensitivity analysis was performed to facilitate the optimization design by using global sensitivity analysis. 展开更多
关键词 space manipulator motion accuracy reliability(MAR) INTERVAL theory CHEBYSHEV INCLUSION function(CIF)
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An analysis of the characteristics of crustal magnetic anomaly in China based on CHAMP satellite data 被引量:3
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作者 jianguo zhang Xiaodong Yang +1 位作者 Jungang Yan Xiaoping Wu 《Geodesy and Geodynamics》 2018年第4期328-333,共6页
Based on the observation data of CHAMP satellite from 2006 to 2009, a 2D crustal magnetic anomaly model in China is established to study the distribution characteristics of crustal magnetic anomaly. In this paper, the... Based on the observation data of CHAMP satellite from 2006 to 2009, a 2D crustal magnetic anomaly model in China is established to study the distribution characteristics of crustal magnetic anomaly. In this paper, the 2D anomaly model is derived from the Legendre polynomial expansion of harmonic term N =6-50. The result shows that many elaborate structures reflected in magnetic anomaly map well correspond to the geologic structures in China and its adjacent area. The magnetic anomaly at low satellite height behaves complexly, which is mainly caused by the magnetic disturbance of shallow rocks.In contrast, the magnetic field isolines at high satellite height are relatively sparse and only magnetic anomalies of deep crust are reflected. This fact implies that the 2D model of crustal magnetic anomaly provides an important method of the space prolongation of geomagnetic field, and is of theoretical and practice importance in geologic structure analysis and geophysical prospecting. 展开更多
关键词 CHAMP satellite Legendre polynomials Crustal magnetic anomaly Magnetic anomaly model
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