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3D Model Reconstruction of Aluminum Foam Cross-Sectional Sequence Images Based on Milling
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作者 Xu Feng Zhiguo Dong +1 位作者 Bo Li Hui Peng 《Journal of Beijing Institute of Technology》 2025年第5期458-481,共24页
This study introduces a novel method for reconstructing the 3D model of aluminum foam using cross-sectional sequence images.Combining precision milling and image acquisition,high-qual-ity cross-sectional images are ob... This study introduces a novel method for reconstructing the 3D model of aluminum foam using cross-sectional sequence images.Combining precision milling and image acquisition,high-qual-ity cross-sectional images are obtained.Pore structures are segmented by the U-shaped network(U-Net)neural network integrated with the Canny edge detection operator,ensuring accurate pore delineation and edge extraction.The trained U-Net achieves 98.55%accuracy.The 2D data are superimposed and processed into 3D point clouds,enabling reconstruction of the pore structure and aluminum skeleton.Analysis of pore 01 shows the cross-sectional area initially increases,and then decreases with milling depth,with a uniform point distribution of 40 per layer.The reconstructed model exhibits a porosity of 77.5%,with section overlap rates between the 2D pore segmentation and the reconstructed model exceeding 96%,confirming high fidelity.Equivalent sphere diameters decrease with size,averaging 1.95 mm.Compression simulations reveal that the stress-strain curve of the 3D reconstruction model of aluminum foam exhibits fluctuations,and the stresses in the reconstruction model concentrate on thin cell walls,leading to localized deformations.This method accurately restores the aluminum foam’s complex internal structure,improving reconstruction preci-sion and simulation reliability.The approach offers a cost-efficient,high-precision technique for optimizing material performance in engineering applications. 展开更多
关键词 aluminum foam section milling cross-sectional sequence images U-Net neural network 3D model reconstruction compression simulation
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Matrix Representation of Recursive Sequences of Order 3 and Its Applications 被引量:2
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作者 Tianxiao HE Jeff H.-C.LIAO Peter J.-S.SHIUE 《Journal of Mathematical Research with Applications》 CSCD 2018年第3期221-235,共15页
Here presented is a matrix representation of recursive number sequences of order 3 defined by an = pa(n-1) + qa(n-2) + ra(n-3) with arbitrary initial conditions a0, a1 = 0, and a2 and their special cases of Pa... Here presented is a matrix representation of recursive number sequences of order 3 defined by an = pa(n-1) + qa(n-2) + ra(n-3) with arbitrary initial conditions a0, a1 = 0, and a2 and their special cases of Padovan number sequence and Perrin number sequence with initial conditions a0 = a1 = 0 and a2 = 1 and a0 = 3, a1 = 0, and a2 = 2, respectively. The matrix representation is used to construct many well known and new identities of recursive number sequences as well as Pavodan and Perrin sequences. 展开更多
关键词 recursive number sequence of order 3 matrix representation of recursive number sequences Padovan number sequence Perrin number sequence Tribonace polynomial sequence
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A reduced computational load protein coding predictor using equivalent amino acid sequence of DNA string with period-3 based time and frequency domain analysis 被引量:1
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作者 Jayakishan K. Meher Gananath N. Dash +1 位作者 Pramod Kumar Meher Mukesh Kumar Raval 《American Journal of Molecular Biology》 2011年第2期79-86,共8页
Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein codi... Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein coding regions in DNA sequences is based on the period-3 property exhibited by nucleotides in exons. Several approaches based on signal processing tools and numerical representations have been applied to solve this problem, trying to achieve more accurate predictions. This paper presents a new indicator sequence based on amino acid sequence, called as aminoacid indicator sequence, derived from DNA string that uses the existing signal processing based time-domain and frequency domain methods to predict these regions within the billions long DNA sequence of eukaryotic cells which reduces the computational load by one-third. It is known that each triplet of bases, called as codon, instructs the cell machinery to synthesize an amino acid. The codon sequence therefore uniquely identifies an amino acid sequence which defines a protein. Thus the protein coding region is attributed by the codons in amino acid sequence. This property is used for detection of period-3 regions using amino acid sequence. Physico-chemical properties of amino acids are used for numerical representation. Various accuracy measures such as exonic peaks, discriminating factor, sensitivity, specificity, miss rate, wrong rate and approximate correlation are used to demonstrate the efficacy of the proposed predictor. The proposed method is validated on various organisms using the standard data-set HMR195, Burset and Guigo and KEGG. The simulation result shows that the proposed method is an effective approach for protein coding prediction. 展开更多
关键词 GENOMICS Bioinformatics CODON Coding region Amino Acid sequence Fourier Transform Antinotch Filter Periodicity-3 Indicator sequence
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Integration of Sequence Stratigraphic Analysis and 3D Geostatistical Modeling of Pliocene–Pleistocene Delta,F3 Block,Netherlands 被引量:1
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作者 Haris Ahmed KHAN Ali Asghar SHAHID +3 位作者 Muhammad Jahangir KHAN Taher ZOUAGHI Maria Dolores ALVAREZ Syed Danial Mehdi NAQVI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期256-268,共13页
This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this resear... This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this research.The conventional techniques of 3D seismic interpretation were utilized to mark the 11 surfaces on the seismic section.Integration of seismic sequence stratigraphic interpretation,using well logs,and subsequent 3D geostatistical modeling,using seismic data,aided to evaluate the shallow hydrocarbon traps.The resulting models were obtained using System Tract and Facies models,which were generated by using sequential stimulation method and their variograms made by spherical method,moreover,these models are validated via histograms.The CDF curve generated from upscaling of well logs using geometric method,shows a good relation with less percentage of errors(1 to 2 for Facies and 3 to 4 for System Tract models)between upscaled and raw data that complements the resulted models.These approaches help us to delineate the best possible reservoir,lateral extent of system tracts(LST and/or HST)in the respective surface,and distribution of sand and shale in the delta.The clinoform break points alteration observed on seismic sections,also validates the sequence stratigraphic interpretation.The GR log-based Facies model and sequence stratigraphy-based System Tract model of SU-04-2 showed the reservoir characteristics,presence of sand bodies and majorly LST,respectively,mainly adjacent to the main fault of the studied area.Moreover,on the seismic section,SU-04-2 exhibits the presence of gas pockets at the same location that also complements the generated Facies and System Tract models.The generated models can be utilized for any similar kind of study and for the further research in the F3 block reservoir characterization. 展开更多
关键词 sequence stratigraphy facies modeling system tract modeling F3 block North Sea
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Genetic Diversity of Chinese Soybean mosaic virus Strains and Their Relationships with Other Plant Potyviruses Based on P3 Gene Sequences 被引量:1
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作者 YANG Qing-hua LI Kai +1 位作者 ZHI Hai-jian GAI Jun-yi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2184-2195,共12页
Soybean mosaic virus (SMV), a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. A... Soybean mosaic virus (SMV), a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As the P3 gene is thought to be involved in viral replication, systemic infection, pathogenicity, and overcoming resistance, knowledge of the P3 gene sequences of SMV and other potyviruses would be useful in efforts to know the genetic relationships among them and control the disease. P3 gene sequences were obtained from representative isolates of the above-mentioned 16 SMV strains and were compared with other SMV strains and 16 Potyvirus species from the National Center for Biotechnology GenBank database. The P3 genes from the 16 SMV isolates are composed of 1041 nucleotides, encoding 347 amino acids, and share 90.7-100% nucleotide (NT) sequence identities and 95.1-100% amino acid (AA) sequence identities. The P3 coding regions of the 16 SMV isolates share high identities (92.4-98.9% NT and 96.0-100% AA) with the reported Korean isolates, followed by the USA isolates (88.5-97.9% NT and 91.4-98.6% AA), and share low identities (80.5-85.2% NT and 82.1-84.7% AA) with the reported HZ 1 and P isolates from Pinellia ternata. The sequence identities of the P3 genes between SMV and the 16 potyviruses varied from 44.4 to 81.9% in the NT sequences and from 21.4 to 85.3% in the AA sequences, respectively. Among them, SMV was closely related to Watermelon mosaic virus (WMV), with 76.0-81.9% NT and 77.5-85.3% AA identities. In addition, the SMV isolates and potyvirus species were clustered into six distinct groups. All the SMV strains isolated from soybean were clustered in Group I, and the remaining species were clustered in other groups. A multiple sequence alignment analysis of the C-terminal regions indicated that the P3 genes within a species were highly conserved, whereas those among species were relatively variable. 展开更多
关键词 Soybean mosaic virus POTYVIRUS P3 gene homology analysis phylogenetic tree multiple sequence alignment
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Subtle traps prediction using sequence stratigraphy and 3D seismic technology: A case study from Qikou depression in Huanghua basin 被引量:1
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作者 MAO Ning-bo DAI Ta-gen PENG Sheng-lin 《Journal of Central South University of Technology》 2005年第z1期141-145,共5页
Forecasting subtle traps by sequence stratigraphy and 3D seismic data is a sensitive topic in hydrocarbon exploration. Research on subtle traps by geophysical data is the most popular and difficult. Based on the suffi... Forecasting subtle traps by sequence stratigraphy and 3D seismic data is a sensitive topic in hydrocarbon exploration. Research on subtle traps by geophysical data is the most popular and difficult. Based on the sufficiently drilling data, log data, core data and 3D seismic data, sediment sequence of Qikou depression, Huanghua basin was partitioned by using sequence stratigraphy theory. Each sediment sequence system mode was built. Sediment faces of subtle traps were pointed out. Dominating factors forming subtle traps were analyzed. Sandstone seismic rock physics and its response were studied in Tertiary System. Sandstone geophysical response and elastic modulus vary laws with pressure, temperature, porosity, depth were built. Experimental result and practice shows that it is possible using seismic information forecasting subtle traps. Integrated using geology, log, drilling data, special seismic processing technique, interpretation technique, high precision horizon calibration technique, 3D seismic visualizing interpretation, seismic coherence analysis, attribute analysis, logging-constrained inversion, time frequency analysis, subtle trapsobject is identified and interpreted. Finally, advantage object of subtle trap in this area was determined. Bottomland sand stratigraphic and lithologic reservoirs in Qinan slope zone have been founded by means of high resolution 3D seismic data field technique, high resolution 3D seismic data processing technique and seismic wave impendence inversion technique. 展开更多
关键词 Huanghua BASIN sequence STRATIGRAPHY subtle TRAP SEISMIC exploration 3D SEISMIC ultrasonic wave
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Effects of impregnation sequence on the NH_(3)-SCR activity and hydrothermal stability of a Ce-Nb/SnO_(2) catalyst 被引量:1
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作者 Ying Zhu Wenpo Shan +3 位作者 Zhihua Lian Jingjing Liu Yan Zhang Hong He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期450-457,共8页
Hydrothermal stability is crucial for the practical application of deNO_(x)catalyst on diesel vehicles,for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).SnO_(2)-based materials possess superior hy... Hydrothermal stability is crucial for the practical application of deNO_(x)catalyst on diesel vehicles,for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).SnO_(2)-based materials possess superior hydrothermal stability,which is attractive for the development of NH_(3)-SCR catalyst.In this work,a series of Ce-Nb/SnO_(2)catalysts,with Ce and Nb loading on SnO_(2)support,were prepared by impregnation method.It was found that,the NH_(3)-SCR activities and hydrothermal stabilities of the Ce-Nb/SnO_(2)catalysts significantly varied with the impregnation sequences,and the Ce-Nb(f)/SnO_(2) catalyst that firstly impregnated Nb and then impregnated Ce exhibited the best performance.The characterization results revealed that CeNb(f)/SnO_(2)possessed appropriate acidity and redox capability.Furthermore,the strong synergistic effect between Nb and Sn species stabilized the structure and maintained the dispersion of acid sites.This study may provide a new understanding for the effect of impregnation sequence on activity and hydrothermal stability and a new environmental-friendly NH_(3)-SCR catalyst with potential applications for NO_(x)removal from diesel and hydrogenfueled engines. 展开更多
关键词 NO_(x)emission control NH_(3)-SCR Hydrothermal stability Ce-Nb/SnO_(2)catalyst Impregnation sequence
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Type division and controlling factor analysis of 3rd-order sequences in marine carbonate rocks 被引量:1
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作者 Yunbo Zhang Zongju Zhao +4 位作者 Genhou Wang Zaixing Jiang Mingjian Wang Min Zheng Shiben Zhang 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第2期289-298,共10页
Type division and controlling factor analysis of 3rd-order sequence are of practical significance to tec-tonic analysis, sedimentary environment identification, and other geological researches. Based on the comprehens... Type division and controlling factor analysis of 3rd-order sequence are of practical significance to tec-tonic analysis, sedimentary environment identification, and other geological researches. Based on the comprehensive analysis of carbon and oxygen isotope trends, paleobathymetry and spectral-frequency of representative well logs, 3rd-order sequences can be divided into 3 types: (a) global sea level (GSL) sequence mainly controlled by GSL change;(b) tectonic sequence mainly controlled by regional tectonic activity;and (c) composite sequence jointly controlled by GSL change and regional tectonic activity. This study aims to identify the controlling factors of 3rd-order sequences and to illustrate a new method for classification of 3rd-order sequences of the middle Permian strata in the Sichuan Basin, China. The middle Permian strata in the Sichuan Basin consist of 3 basin-contrastive 3rd-order sequences, i.e., PSQ1, PSQ2 and PSQ3. Of these, PSQ1 is a GSL sequence while PSQ2 and PSQ3 are composite sequences. The results suggest that the depositional environment was stable during the deposition of PSQ1, but was activated by tectonic activity during the deposition of the middle Permian Maokou Formation. 展开更多
关键词 Carbon isotope 3rd-Order sequence Milankovitch cycles Middle Permian strata Sichuan Basin
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易洛魁同源盒基因3调控血管周围脂肪组织褐变改变血管损伤的潜在机制
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作者 胡晓咏 宋乾华 +2 位作者 杨朝颖 唐瑞 李红建 《中国组织工程研究》 北大核心 2026年第22期5671-5681,共11页
背景:在医学领域,血管损伤相关疾病备受关注,血管周围脂肪组织褐变与之密切相关,但特定基因在其中的调控机制尚待明晰。目的:初步探讨易洛魁同源盒基因3在血管损伤过程中调控血管周围脂肪组织褐变的潜在机制。方法:解析血管周围脂肪组... 背景:在医学领域,血管损伤相关疾病备受关注,血管周围脂肪组织褐变与之密切相关,但特定基因在其中的调控机制尚待明晰。目的:初步探讨易洛魁同源盒基因3在血管损伤过程中调控血管周围脂肪组织褐变的潜在机制。方法:解析血管周围脂肪组织相关单细胞测序数据矩阵GSE275779,探讨易洛魁同源盒基因3在不同细胞亚群中的表达水平及功能;结合脂肪细胞相关芯片和测序表达谱GSE44059、GSE7032、GSE185518、GSE168387,筛选差异基因并验证易洛魁同源盒基因3在棕色脂肪细胞分化过程中的表达水平;基于msigdb数据库和ChIP-seq数据库GTRD筛选易洛魁同源盒基因3的下游靶基因。在脂肪前体细胞中干扰易洛魁同源盒基因3和过表达视黄醇饱和酶,采用qPCR和Western blot检测脂肪细胞褐变相关基因的mRNA和蛋白表达水平。结果与结论:生物信息学分析结果显示,脂肪细胞特征因子PR结构域蛋白16、细胞死亡诱导DFFA样效应蛋白A和解偶联蛋白1等在糖尿病患者的血管周围脂肪组织中显著下调,且这些基因均参与脂肪褐变;结合高通量测序数据分析发现易洛魁同源盒基因3在棕色脂肪组织中高表达,并参与了棕色脂肪的分化;进一步筛选出视黄醇饱和酶为易洛魁同源盒基因3的下游靶基因,且它的水平随着棕色脂肪的分化而差异表达。在成熟棕色脂肪细胞中敲低易洛魁同源盒基因3,会导致视黄醇饱和酶和脂肪褐变相关标志物(解偶联蛋白1、过氧化物酶体增殖物激活受体γ辅激活因子1α、PR结构域蛋白16)的表达均降低。在视黄醇饱和酶回复实验中,视黄醇饱和酶过表达显著上调脂肪褐变相关标志物的蛋白水平,但不影响易洛魁同源盒基因3的表达。此研究初步揭示了易洛魁同源盒基因3在血管损伤过程中调控血管周围脂肪组织褐变的潜在机制。 展开更多
关键词 血管损伤 血管周围脂肪组织 生物信息学 单细胞测序 褐变 易洛魁同源盒基因3(IRX3)
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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:1
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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Cloning and Sequence Analysis of cDNA Encoding MRJP3 of Apis cerana cerana
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作者 SU Song-kun ZHNEG Huo-qing +2 位作者 CHEN Sheng-lu ZHONG Bo-xiong Stefan Albert 《Agricultural Sciences in China》 CAS CSCD 2005年第9期707-713,共7页
By screening the worker (Apis cerana cerana) heads cDNA library using a fragment of the mrjp3 gene of Apis cerana as probe, 120 positive clones were obtained. The clone containing A. cerana cerana MRJP3 (AccMRJP3)... By screening the worker (Apis cerana cerana) heads cDNA library using a fragment of the mrjp3 gene of Apis cerana as probe, 120 positive clones were obtained. The clone containing A. cerana cerana MRJP3 (AccMRJP3) cDNA was selected. Based on the sequencing of the inserts of the positive clone, a sequence of AccMRJP3 cDNA which is 1 887 bp long including a poly (A) tail was obtained. The AccMRJP3 cDNA encompassed an open-reading frame (ORF) with 1 779 bp encoding 593 amino acids. The un-translated regions (UTR) of the 5′ end and 3′end are 46 bp and 160 bp in length, respectively. Similar to AmMRJP3 and AdMRJP3, the putative AccMRJP3 also has a repetitive region. The comparison of the repetitive region of AccMRJP3, AmMRJP3 and AdMRJP3 shows some differences between them. 展开更多
关键词 Apis cerana cerana MRJP3 Gene cloning sequence analysis
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Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait
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作者 Haoxue Wu Xiaohan Zhang +5 位作者 Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期627-640,共14页
Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har... Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes. 展开更多
关键词 Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation
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Content, Density, Illuviation Mode and Depth of CaCO<sub>3</sub>in Soils of Semiarid-Arid Qilian Mountains—An Altitude Sequence Study of the Hulugou Watershed
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作者 Ka Lin Decheng Li +4 位作者 Ganlin Zhang Yuguo Zhao Jinling Yang Feng Liu Xiaodong Song 《Agricultural Sciences》 2017年第6期479-491,共13页
The parental material of soils in the Qilian Mountains of northwest China is mainly aeolian loess containing CaCO3 which may remain in soils under the semiarid-arid climate. To disclose the CaCO3 characteristics chang... The parental material of soils in the Qilian Mountains of northwest China is mainly aeolian loess containing CaCO3 which may remain in soils under the semiarid-arid climate. To disclose the CaCO3 characteristics change with the altitude and the terrain attributes, we surveyed 18 soil profiles in an altitude sequence from 3076 m to 4510 m in the Hulugou Watershed in the Qilian Mountains, measured CaCO3 contents of all genetic horizon samples, analyzed the densities, illuviation modes and depths of CaCO3 in the profiles, extracted values of the terrain attributes of the profiles including altitude slope, aspect, plane curvature, profile curvature and terrain wetness index (TWI) from the 90 m resolution SRTM3 DEM data on ArcGIS 9.3 platform. We found that CaCO3 weighted content of the profiles ranged from 1.30 g·kg-1 to 93.09 g·kg-1, CaCO3 density from 0.05 kg/m2 to 75.69 kg/m2, CaCO3 illuviation depth from 12 cm to 54 cm. CaCO3 illuviation modes could be divided into three types, i.e., no illuviation mode in which the profile has only A horizon or CaCO3 content -1, middle illuviation mode in which CaCO3 accumulated in a middle horizon, and down illuviation mode in which CaCO3 content increases with the depth. CaCO3 weighted content, density and illuviation depth had significant correlation with certain terrain attributes. In general, the altitude sequence is an effective way to study CaCO3 characteristics in the alpine region, and the data of terrain attributes which can influence the precipitation and its redistribution in soil are potential in predicting soil CaCO3 characteristics in the alpine region. 展开更多
关键词 CaCO3 ALTITUDE sequence Terrain Attributes The Hulugou WATERSHED The QILIAN Mountains
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Characteristics of Seismic Sequences and Early Tendency Judgment for Yutian M_S7.3 Earthquake in 2014
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作者 Song Chunyan Zhang Linlin +2 位作者 Nie Xiaohong Xia Aiguo Wei Yunyun 《Earthquake Research in China》 CSCD 2015年第3期352-362,共11页
The basic parameters,seismogenic structure and seismic sequences characteristics of the Yutian MS7. 3 earthquake on February 12,2014 are introduced and compared to the Yutian MS7. 3 earthquake in 2008. The results sho... The basic parameters,seismogenic structure and seismic sequences characteristics of the Yutian MS7. 3 earthquake on February 12,2014 are introduced and compared to the Yutian MS7. 3 earthquake in 2008. The results show that the MS5. 4 earthquake is regarded as an immediate foreshock of the Yutian MS7. 3 main shock. The frequency of strong aftershock sequences was low and their number declined quickly,and the maximum aftershock was a MS5. 7 earthquake. According to analysis of the historical earthquake sequence type,and parameter of h-value,b-value and energy release ratio between main shock and sequence etc.,we found the preliminary conclusion that the Yutian MS7. 3 earthquake sequence in 2014 was a foreshock-main shock-aftershock type. 展开更多
关键词 Yutian Ms7. 3 earthquake Seismic sequence Strong aftershock
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Division and Correlation of Lacustrine Gravity Flow Reservoirs Based on High-Resolution Sequence Stratigraphic Analysis—Taking Oil Formation I of Lower Es3 in Wuhaozhuang Oilfield as an Example
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作者 Yiming Zhang Hongliang Wang 《Journal of Geoscience and Environment Protection》 2022年第6期156-169,共14页
The phase change of lacustrine gravity flow deposition is fast and complex. In its reservoir division and correlation, the isochronous problem is very important. Taking the oil formation I of Es3 in Wuhaozhuang oilfie... The phase change of lacustrine gravity flow deposition is fast and complex. In its reservoir division and correlation, the isochronous problem is very important. Taking the oil formation I of Es3 in Wuhaozhuang oilfield as an example, through the analysis of stratigraphic drilling and logging data in the study area, according to the genetic types of different levels of base level cycle interfaces and the characteristics of high-resolution sequence stratigraphy, this paper subdivides the lacustrine gravity flow oil layer of lower Es3 in Wuhaozhuang Oilfield, divides it into four short-term base level cycle sequences, and establishes the high-resolution isochronous stratigraphic framework of this interval. It is found that the mid-term, short-term and ultra short-term base level cycles correspond to the oil formation, sand layer group and single layer in the oil layer correlation unit of the oilfield respectively. Based on this, the oil layer correlation unit of the interval is divided, and the sublayer correlation model is established according to the identification characteristics of the short-term base level cycle. 展开更多
关键词 High-Resolution sequence Stratigraphy Formation I of Lower Es3 Reservoir Division and Correlation Lacustrine Gravity Flow Wuhaozhuang Oilfield
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Seismic Sequence Characteristics and Precursory Anomalies of the M_S6.3 and M_S6.4 Da Qaidam Earthquakes in 2008~2009
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作者 Ma Yuhu Liu Wenbang +2 位作者 Wang Peiling Yang Xiaoxia Chen Yuhua 《Earthquake Research in China》 2013年第2期191-204,共14页
In this paper,the seismogenic structures of the Da Qaidam strong earthquakes are preliminarily discussed by using the regional seismotectonic data and focal mechanism solutions. Analysis is done on the temporal and sp... In this paper,the seismogenic structures of the Da Qaidam strong earthquakes are preliminarily discussed by using the regional seismotectonic data and focal mechanism solutions. Analysis is done on the temporal and spatial distribution characteristics of the two strong earthquake sequences in Da Qaidam in combination with the sequence distribution characteristics of the M6. 6 earthquake of 2003 and the five strong earthquakes of about M5. 0 in 2004 in Delingha. At the same time,the regional characteristics of the historical seismic activity are also investigated. Preliminary analysis is done on the influence of the two M8. 0 earthquakes in the past 10 years on this region. Precursory anomalies and their characteristics are discussed in combination with the analysis of the precursor observation data of Qinghai Province. 展开更多
关键词 The MS 6. 3 and MS 6. 4 Da Qaidam earthquakes in 2008 2009 Earthquake sequence activity Precursory anomaly
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3D-CISS序列与3D-TSE序列对Ⅶ~Ⅸ对颅神经成像质量的比较 被引量:17
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作者 梁长虎 柳澄 +4 位作者 李坤成 黄杰 乌大尉 王海燕 赵振美 《医学影像学杂志》 2007年第9期891-894,共4页
目的:通过3D-CISS序列与3D-TSE序列对Ⅶ-Ⅸ对颅神经成像质量的比较,确定3D-CISS序列对脑脊液包绕的Ⅶ-Ⅸ对颅神经和淋巴液充盈的内耳迷路成像显示的优势。方法:应用3D-CISS序列与3D-TSE序列分别对第Ⅶ-Ⅸ对颅神经及内耳迷路进行MR成... 目的:通过3D-CISS序列与3D-TSE序列对Ⅶ-Ⅸ对颅神经成像质量的比较,确定3D-CISS序列对脑脊液包绕的Ⅶ-Ⅸ对颅神经和淋巴液充盈的内耳迷路成像显示的优势。方法:应用3D-CISS序列与3D-TSE序列分别对第Ⅶ-Ⅸ对颅神经及内耳迷路进行MR成像,在MPR图像及MIP重建图像上最大程度的显示颅神经及内耳迷路,并对两种序列的成像质量进行统计比较。结果:面神经的脑池段、内听道近段及远段、前庭蜗神经的脑池段及内听道近段、耳蜗、前庭及半规管在两个序列中全部以100%的几率显示;蜗神经、前庭上神经、前庭下神经及舌咽神经在3D-CISS序列、3D-TSE序列的显示几率依次分别为:100%、81.2%;100%、51.4%;100%、42.0%;100%、57.1%;面神经、前庭蜗神经的内听道段、内耳迷路、舌咽神经的3D-CISS序列成像质量明显优于3D-TSE序列成像;面神经、前庭蜗神经的脑池段3D-CISS序列成像质量略优于3D-TSE序列。结论:对于被脑脊液包绕的颅神经和淋巴液充盈的内耳迷路的成像,3D-CISS序列是最佳的选择。 展开更多
关键词 磁共振成像 3D-CISS序列 3d-tse序列 多平面重组 颅神经
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3D-TSE序列在三叉神经痛病因诊断中的价值 被引量:8
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作者 杨利霞 贾文霄 李琛玮 《临床放射学杂志》 CSCD 北大核心 2004年第11期936-940,共5页
目的 探讨MRI三维快速自旋回波 (3D TSE)序列在三叉神经痛 (TN)病因研究中的价值。资料与方法 应用 3D TSE序列 ,结合常规MRI序列 ,分析 5 0例TN患者和 5 0名正常对照者的MRI表现及手术结果。结果  (1) 5 0名正常对照者 10 0侧脑池... 目的 探讨MRI三维快速自旋回波 (3D TSE)序列在三叉神经痛 (TN)病因研究中的价值。资料与方法 应用 3D TSE序列 ,结合常规MRI序列 ,分析 5 0例TN患者和 5 0名正常对照者的MRI表现及手术结果。结果  (1) 5 0名正常对照者 10 0侧脑池段三叉神经MRI检查中 ,11侧存在三叉神经血管接触。 5 0名TN患者疼痛侧有血管压迫或接触的为 32例 ,非疼痛侧 5 0侧三叉神经中 ,有血管接触的为 7例 ,经统计学分析 ,TN患者疼痛有无与是否存在血管压迫或接触有统计学意义 (P <0 .0 0 5 )。 (2 ) 5 0例TN患者疼痛侧 ,MRI诊断TN病因中血管压迫或接触占 6 4 % (32 / 5 0 ) ;肿瘤性病变占 16 % (8/ 5 0 ) ;其他占 2 0 % (10 / 5 0 )。 (3)根据手术结果 ,3D TSE序列对TN诊断的敏感性为 10 0 % ,特异性为 80 %。结论 三叉神经脑池段的血管压迫或接触是TN的主要病因 ,3D TSE成像能清晰显示三叉神经与邻近血管、肿瘤性病变或其他病变之间的关系 。 展开更多
关键词 3d-tse序列 三叉神经痛 病因 诊断 3d-tse 磁共振成像
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3D-TSE序列结合DRIVE诊断面肌痉挛病因的价值 被引量:2
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作者 杨利霞 贾文霄 +2 位作者 何乐 丁爽 陈宏 《新疆医科大学学报》 CAS 2008年第4期374-376,共3页
目的:探讨MRI三维快速自旋回波序列(3D-TSE)加入DRIVE脉冲对面肌痉挛(HFS)患者的病因诊断及图像质量改善的价值。方法:应用3D-TSE及加入DRIVE脉冲的序列,对55例HFS患者行桥小脑角薄层扫描,并行后颅窝探察术,分析HFS患者桥小脑角区面神... 目的:探讨MRI三维快速自旋回波序列(3D-TSE)加入DRIVE脉冲对面肌痉挛(HFS)患者的病因诊断及图像质量改善的价值。方法:应用3D-TSE及加入DRIVE脉冲的序列,对55例HFS患者行桥小脑角薄层扫描,并行后颅窝探察术,分析HFS患者桥小脑角区面神经与周围血管等结构的关系,并与手术结果进行对照。结果:(1)MRI诊断面肌痉挛病因中血管压迫占95%(52/55),神经源肿瘤占3.6%(2/55),其它占1.8%(1/55)。HFS患者痉挛侧与非痉挛侧的血管神经压迫差异有统计学意义(P<0.005)。(2)3D-TSE序列与加入DRIVE脉冲序列比较,可以将扫描时间缩短50%,图像质量明显改善。手术结果表明,3D-TSE序列对面肌痉挛患者诊断的敏感性为96%,特异性为100%;3D-TSE加入DRIVE脉冲序列对面肌痉挛患者诊断的敏感性为98%,特异性为100%。结论:面神经脑池段的血管压迫是面肌痉挛的主要病因,3D-TSE加入DRIVE脉冲可以明显提高图像质量,缩短扫描时间,值得推广应用。 展开更多
关键词 面肌痉挛 病因 3d-tse DRIVE
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3.0T磁共振3D-SPACE序列与3D-TSE序列用于颅神经成像的效果比较 被引量:6
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作者 吕海莲 罗树彬 《山东医药》 CAS 北大核心 2011年第7期83-84,共2页
目的比较3.0T MRI检查中3D-SPACE序列与3D-TSE序列对颅神经成像的质量。方法分别应用3D-SPACE序列与3D-TSE序列对47例受检者Ⅰ~Ⅻ对颅神经行MRI,将采集到的影像利用Siemens 3D软件进行最大强度(MIP)及最小强度重建(min-IP),并对两种序... 目的比较3.0T MRI检查中3D-SPACE序列与3D-TSE序列对颅神经成像的质量。方法分别应用3D-SPACE序列与3D-TSE序列对47例受检者Ⅰ~Ⅻ对颅神经行MRI,将采集到的影像利用Siemens 3D软件进行最大强度(MIP)及最小强度重建(min-IP),并对两种序列的图像显示情况进行比较。结果对于第Ⅰ、Ⅲ、Ⅳ、Ⅵ、Ⅸ、Ⅹ、Ⅺ颅神经3D-SPACE序列显示率明显高于3D-TSE序列(P<0.05),对于第Ⅱ、Ⅴ、Ⅶ、Ⅷ、Ⅻ对颅神经显示率略高于3D-TSE序列(P>0.05)。结论在3.0T MRI检查中应用3D-SPACE序列所获颅神经(尤其脑池段)成像效果优于3D-TSE序列,且扫描时间更短;扫描前应协助患者处于较为舒适的姿势并进行适当固定,以获得最佳检查效果。 展开更多
关键词 3D-SPACE序列 颅神经 3d-tse序列 磁共振成像
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