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Sedimentary Characteristics and Evolution of the High-resolution Sequence Stratigraphic Framework of the Taiyuan Formation in the Hangjinqi Area,Northern Ordos Basin
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作者 ZHAO Mingsheng TIAN Jingchun +1 位作者 SU Bingrui ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 2026年第1期54-68,共15页
The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theor... The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theoretical and practical significance for guiding oil and gas exploration.The sedimentary facies and sedimentary evolution of the high-resolution sequence framework of the Carboniferous Taiyuan Formation in the Hangjinqi area have been systematically analyzed for the first time by drilling,logging and seismic data.The results show that four types of sequence interfaces can be identified in the Taiyuan Formation:regional unconformity surfaces,scour surfaces,lithologic-lithofacies transformation surfaces and flooding surfaces.According to the sedimentary response caused by the upward and downward movements of the base level at different levels,the Taiyuan Formation can be divided into 2 long-term cycles(LSC_(1)-LSC_(2)),4 mid-term cycles(MSC_(1)-MSC4)and 7 short-term cycles(SSC_(1)-SSC7).The long-and mid-term cycles correspond to members T_(1)and T_(2)and layers T_(1)-1,T_(1-2),T_(2-1),and T_(2)-2,respectively.Long-term cycles are dominated by C_(1);mid-term cycles are dominated by C_(1)and C_(2),followed by A2;and short-term cycles are dominated by C_(1),C_(2),A1 and A2.Under the high-resolution sequence stratigraphic framework,the Hangjinqi area underwent a transformation of fan delta and tidal flat depositional systems during the Taiyuan Formation sedimentary period.In the MSC_(1)-MSC_(2)stage,owing to a large-scale paleocontinent,the fan delta sedimentary body,which was limited in scale and scope,developed only in the southeastern corner and gradually transitioned basinward to tidal flat facies.In the MSC3-MSC4 stage,as the paleocontinent continuously decreased and the sedimentary range expanded,fan-delta plain sedimentation began in the study area.Several braided distributary channels with poor connectivity developed on the fan-delta plain,and between them were floodplains and peat swamps. 展开更多
关键词 high-resolution sequence framework sedimentary characteristics sedimentary evolution Taiyuan Formation Hangjinqi area northern Ordos Basin
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HIGH-RESOLUTION SEQUENCE STRATIGRAPHIC ANALYSIS OF THE PERMIAN IN THE WESTERN SHANDONG AND HUAINAN-HUAIBEI COALFIELDS 被引量:1
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作者 李增学 魏久传 韩美莲 《Journal of Coal Science & Engineering(China)》 1999年第1期1-10,共10页
The sedimentary characteristics and their combination succession of the Permian in the Shandong nd Huainan-Huaibei coalfields are analyzed. The mid-and short-term stratigraphic base-level cycles are identified. High-r... The sedimentary characteristics and their combination succession of the Permian in the Shandong nd Huainan-Huaibei coalfields are analyzed. The mid-and short-term stratigraphic base-level cycles are identified. High-resolution sequences are divided based on the above results. The study shows that the stratigraphic base-level cyclic method is an efficient way in the determination of the high-resolution sequences, especially in the classification of tbe terrestrial and transitional depositional succession. 展开更多
关键词 PERMIAN stratigraphic base-level cycles high-resolution sequence stratigraphic analysis western Shandong coalfields Huainan-Huaibei coalfields
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High-Resolution Sequence Stratigraphy of Shallow Lacustrine Delta Front: The Second Member of Sangonghe Formation, Central Junggar Basin 被引量:1
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作者 SONG Licai LIU Chenglin +1 位作者 ZHANG Jiaodong QU Hongjie 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第1期314-315,共2页
Shallow lacustrine delta front (SLDF) comprises mainly sheetlike subaqueous distributary channels (SDC) formed in shallow, gentle, and tectonically steady slope (Cai and Zhu, 2011). SDC proves an important hydro... Shallow lacustrine delta front (SLDF) comprises mainly sheetlike subaqueous distributary channels (SDC) formed in shallow, gentle, and tectonically steady slope (Cai and Zhu, 2011). SDC proves an important hydrocarbon reservoir type in the Daqing oilfield, Changqing oilfield, and the newly discovered Moxizhuang oilfield in Central Junggar Basin. However, SDC tends to prograde quickly and move laterally frequently, 展开更多
关键词 Central Junggar Basin high-resolution sequence Stratigraphy of Shallow Lacustrine Delta Front
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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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High-resolution sequence architecture and depositional evolution of the Quaternary in the northeastern shelf margin of the South China Sea 被引量:1
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作者 Hanyao Liu Changsong Lin +4 位作者 Zhongtao Zhang Bo Zhang Jing Jiang Hongxun Tian Huan Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第5期86-98,共13页
The northeastern shelf margin of the South China Sea(SCS) is characterized by the development of large scale foresets complexes since Quaternary. Based on integral analysis of the seismic, well logging and paleontolog... The northeastern shelf margin of the South China Sea(SCS) is characterized by the development of large scale foresets complexes since Quaternary. Based on integral analysis of the seismic, well logging and paleontological data, successions since ~3.0 Ma can be defined as one composite sequence, consist of a set of regional transgressive to regressive sequences. They can be further divided into six 3 rd order sequences(SQ0–SQ5) based on the Exxon sequence stratigraphic model. Since ~1.6 Ma, five sets of deltaic systems characterized by development of wedge-shaped foresets complexes or clinoforms had been identified. High-resolution seismic data and the thick foresets allowed further divided of sub-depositional sequences(4 th order) of regression to transgression, which is basically consistent with published stacked benthic foram O-isotope records. Depositional systems identified in the study area include deltaic deposits(inner-shelf deltas and shelf-edge deltas), incised valleys, and slope slumping massive deposits. Since ~1.6 Ma, clinoforms prograded from the southern Panyu Lower Uplift toward the northern Baiyun Depression, shelf slope break migrated seaward, whereas the shelf edge of SQ0 migrated landward. The development of incised valleys in the continental shelf increased upward,especially intensive on the SB3 and SB2. The slumping massive deposits increased abruptly since SB2, which corresponds to the development of incised valleys. The evolution of depositional systems of continental slope mainly controlled by the combined influence of sea level changes, tectonic movements, sediment supply and climate changes. Since ~3.0 Ma, relative sea level of the northern SCS had been experienced transgression(~3.0 Ma BP) to regression(~1.6 Ma BP). The regional regression and maximum transgressions of the composite sequences were apparently enhanced by uplift or subsidence related to tectono-thermal events. In addition,climatic variations including monsoon intensification and the mid-Pleistocene transition may have enhanced sediment supply by increasing erosion rate and have an indispensable influence on the development of the incised valleys and 5 sets of deltaic systems since ~1.6 Ma. 展开更多
关键词 sequence ARCHITECTURE DEPOSITIONAL systems continental slope QUATERNARY Zhujiang(Pearl)River MOUTH Basin
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On the analysis of the high-resolution sequence stratigraphy and coal accumulating law of jurassic in Ordos Basin 被引量:8
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作者 李增学 韩美莲 +3 位作者 李江涛 余继峰 吕大炜 柳汉丰 《Journal of Coal Science & Engineering(China)》 2008年第1期85-91,共7页
The strata of Jurassic was divided into three tectonic sequences and eight se- quences of third rank,according to the developing feature of the tectonic inconformity and the transforming feature of the depositional sy... The strata of Jurassic was divided into three tectonic sequences and eight se- quences of third rank,according to the developing feature of the tectonic inconformity and the transforming feature of the depositional system tracts.Also the identification and the division of the base-level cycle of different period were carried through.Therefore three cycles of super period,eight cycles of long period,twenty-four cycles of middle period and some cycles of short period were identified.From the overall character of the coal-accu- mulation in the Mesozoic,we can see that the Yan'an formation is of the best nature of coal bearing.When the coal bearing systems of Jurassic were depositing,the Ordos area is the coal accumulating basin of terrene of large scale and located in the same tectonic unit.But the local structure of different part and the paleolandform are different in the basin which resulted in the difference of the depositional environment.So the layer number and the distribution of the thickness of the coal beds are different in the different part of the ba- sin.The coal-accumulating action migrated regularly along with the development,evolve- ment and migration of the depositional systems.The layer numbers of the coal beds, which can be mined,are more in the north and west fringe of the basin,whose distributing area is extensive,and they are more steady in the landscape orientation,also the total thickness is great.Therefore the nature of coal bearing and the coal-accumulating action of different part changed obviously in the space in Ordos area. 展开更多
关键词 high resolution sequence stratigraphy base-level cycle coal accumulating law the migration of rich-coal units
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HIGH-RESOLUTION SEQUENCE DIVISION AND TRANSGRESSIVE EVENTS COAL FORMATIONIN SOUTHEASTERN NORTH CHINA EPICONTINENTAL BASIN 被引量:1
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作者 李增学 魏久传 +1 位作者 韩美莲 杨锋杰 《Journal of Coal Science & Engineering(China)》 2000年第1期1-9,共9页
The sea level changes in the Paleozoic epicontinental basin were of high frequency and the transgressive events were episodic.This kind of sea level changes controlled both the basin filling and the coal accumulation ... The sea level changes in the Paleozoic epicontinental basin were of high frequency and the transgressive events were episodic.This kind of sea level changes controlled both the basin filling and the coal accumulation within the basin.Coal accumulation in the transgressive process is one of the typical features of the North China epicontinental basin.High resolution sequence analysis to the Permo carboniferous coal series based on the core observation indicates that the epicontintental coal bearing succession can be divided into 1 tectonic sequence (the original type of basin filling), 3 supersequences, 12 third order sequences and about 48 parasequences.The third order sequences are of dual configuration sequences that are composed of transgressive systems tract in the lower part and highstand systems tract in the upper part.The transgressive systems tracts are relatively thin in thickness and have fewer parasequences (commonly 1 to 2), while the highstand systems tracts are thick, generally consist of several parasequences. 展开更多
关键词 epicontinental basin Permo carboniferous high resolution sequences coal formation in the transgressive process
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Logging Data High-Resolution Sequence Stratigraphy
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作者 李洪奇 谢寅符 +1 位作者 孙中春 罗兴平 《Journal of China University of Geosciences》 SCIE CSCD 2006年第2期173-180,共8页
The recognition and contrast of bed sets in parasequence is difficult in terrestrial basin high-resolution sequence stratigraphy. This study puts forward new methods for the boundary identification and contrast of bed... The recognition and contrast of bed sets in parasequence is difficult in terrestrial basin high-resolution sequence stratigraphy. This study puts forward new methods for the boundary identification and contrast of bed sets on the basis of manifold logging data. The formation of calcareous interbeds, shale resistivity differences and the relation of reservoir resistivity to altitude are considered on the basis of log curve morphological characteristics, core observation, cast thin section, X-ray diffraction and scanning electron microscopy. The results show that the thickness of calcareous interbeds is between 0.5 m and 2 m, increasing on weathering crusts and faults. Calcareous interbeds occur at the bottom of a distributary channel and the top of a distributary mouth bar. Lower resistivity shale (4-5 Ω · m) and higher resistivity shale (〉 10Ω·m) reflect differences in sediment fountain or sediment microfacies. Reservoir resistivity increases with altitude. Calcareous interbeds may be a symbol of recognition for the boundary of bed sets and isochronous contrast bed sets, and shale resistivity differences may confirm the stack relation and connectivity of bed sets. Based on this, a high-resolution chronostratigraphic frame- work of Xi-1 segment in Shinan area, Junggar basin is presented, and the connectivity of bed sets and oil-water contact is confirmed. In this chronostratigraphic framework, the growth order, stack mode and space shape of bed sets are qualitatively and quantitatively described. 展开更多
关键词 Junggar basin logging data sequence stratigraphy calcareous interbeds shale resistivity relationship of resistivity to altitude reservoir connectivity.
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High-Resolution Sequence Stratigraphy and Coal Accumulating Models of the Permo-Carboniferous Coal Measures in Southwestern Shanxi
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作者 Zhenghui Xiao Longyi Shao +1 位作者 Hao Wang Jing Lu 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期143-144,共2页
The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thic... The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thickness are strongly controlled by the depositional environments and the sequence stratigraphic framework.This paper analyzes the high-resolution sequence stratigraphy of the Permo-Carbo-niferous Taiyuan and Shanxi Formations. 展开更多
关键词 sequence stratigraphicframework coal-accumulating model Permo-Carboniferous Qinshui Basin
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High-resolution sequence stratigraphic framework and target sand bodies correlation of tight oil reservoirs in the Upper Triassic Yanchang Formation, Ordos Basin
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作者 Xiulin Hou Mingqiu Hou +5 位作者 Qingfu Feng Yuxiang Xiao Zhengdong Lei Lingbin Lai Siyang Li Hongyu Tian 《Petroleum Research》 2025年第4期749-763,共15页
In this study,we developed a high-resolution stratigraphic framework for the Yanchang Formation in the Huachi Block of the Qingyang Oilfield,located in the Ordos Basin,northwest China.Using well log and seismic data,w... In this study,we developed a high-resolution stratigraphic framework for the Yanchang Formation in the Huachi Block of the Qingyang Oilfield,located in the Ordos Basin,northwest China.Using well log and seismic data,we traced and correlated sweet-spot sand bodies in tight oil reservoirs.Three long-term base-level cycles were identified in the Yanchang Formation,and five medium-term base-level cycles were delineated from the Chang 72 sub-Member to the Chang 4+5 Members,corresponding to five distinct oil groups.The primary production layer,Oil Group 3,was further divided into short-term and very short-term base-level cycles to facilitate the prediction of hydrocarbon target zones.Sweet-spot sand bodies were traced and correlated within very short-term cycles.The sweet-spot sand bodies are mainly sublacustrine channel deposits in the delta front,which were mainly developed in the five single layers(3-1-2,3-1-3,3-1-4,3-2-2,3-2-3 and 3-2-5)of the small layers 3-1 and 3-2 during the regression periods of base-level cycles.The sweet spot sand bodies within the small layer 3-2 are derived from three sets of sources in the northeast,northwest,and south of the basin.The Class I sweet spot is distributed within the single layer 3-2-5,with an average thickness of about 6 m,covering about 25%of the study area.The Class II sweet spot is developed in all five single layers,with the thickest and largest sweet-spot sand body in the Single layer 3-2-3,covering about 90%of the study area.This study highlights the critical importance of establishing a high-resolution sequence stratigraphic framework for the refined delineation of sweet-spot sand bodies within a deltaic-lacustrine depositional system.Additionally,sublacustrine fan deposits formed during the regressive semi-cycle were identified as key sweet spots in the study area. 展开更多
关键词 Ordos Basin high-resolution sequence stratigraphic framework Tight oil reservoirs Stratigraphic correlation
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High-resolution sequence stratigraphy of the Ponta do Mel Formation,Potiguar Basin,Brazil:Insights into shallow-marine carbonate reservoir zonation and characterisation
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作者 A.J.C.Magalhaes A.H.Melo +3 位作者 G.J.S.Terra D.G.C.Fragoso U.M.Soares F.P.Lima-Filho 《Petroleum Research》 2025年第2期304-319,共16页
This comprehensive study establishes a novel high-resolution sequence stratigraphic framework for a shallow,warm,land-tied carbonate-rimmed shelf represented by the Ponta do Mel Formation.Integration of cores and cutt... This comprehensive study establishes a novel high-resolution sequence stratigraphic framework for a shallow,warm,land-tied carbonate-rimmed shelf represented by the Ponta do Mel Formation.Integration of cores and cuttings with seismic and well-log data provides the detailed subsurface stratigraphic framework encompassing two fourth-order genetic sequences.The high-resolution approach unveiled the step-by-step depositional and diagenetic evolution of the Ponta do Mel Formation at the fourth-order systems tracts scale and established the reservoir zonation.In each zone,the lateral contact between high-energy outer shelf and shelf rim potential reservoirs and low-energy inner shelf deposits constitutes critical reservoir heterogeneities that may affect production planning and development projects.Moreover,the reservoir scale enabled discussion on the controls on deposition,high-resolution sequence architecture,diagenesis,and insight into the zonation and characterisation of similar oil and gas reservoirs worldwide. 展开更多
关键词 Carbonate-rimmed shelf Ponta do Mel Formation Potiguar basin high-resolution sequence stratigraphy Reservoir zonation and characterisation
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HUANNet: A High-Resolution Unified Attention Network for Accurate Counting
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作者 Haixia Wang Huan Zhang +2 位作者 Xiuling Wang Xule Xin Zhiguo Zhang 《Computers, Materials & Continua》 2026年第1期1722-1741,共20页
Accurately counting dense objects in complex and diverse backgrounds is a significant challenge in computer vision,with applications ranging from crowd counting to various other object counting tasks.To address this,w... Accurately counting dense objects in complex and diverse backgrounds is a significant challenge in computer vision,with applications ranging from crowd counting to various other object counting tasks.To address this,we propose HUANNet(High-Resolution Unified Attention Network),a convolutional neural network designed to capture both local features and rich semantic information through a high-resolution representation learning framework,while optimizing computational distribution across parallel branches.HUANNet introduces three core modules:the High-Resolution Attention Module(HRAM),which enhances feature extraction by optimizing multiresolution feature fusion;the Unified Multi-Scale Attention Module(UMAM),which integrates spatial,channel,and convolutional kernel information through an attention mechanism applied across multiple levels of the network;and the Grid-Assisted Point Matching Module(GPMM),which stabilizes and improves point-to-point matching by leveraging grid-based mechanisms.Extensive experiments show that HUANNet achieves competitive results on the ShanghaiTech Part A/B crowd counting datasets and sets new state-of-the-art performance on dense object counting datasets such as CARPK and XRAY-IECCD,demonstrating the effectiveness and versatility of HUANNet. 展开更多
关键词 Accurate counting high-resolution representations point-to-point matching
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Integrating high-resolution mass spectrometry and transcriptomics to explore the therapeutic mechanism of Sanhuang Oil in diabetic foot
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作者 Ping Sun Yu-Feng Zhang +4 位作者 Shuang Li Wei Zhang Peng-Fei Zhao Chen-Xia Li Chen-Ning Zhang 《Traditional Medicine Research》 2026年第1期19-38,共20页
Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-... Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-inflammatory,and immunomodulatory activities.However,its active constituents and mechanisms of action against diabetic foot remain to be elucidated.Methods:In this study,the chemical constituents of Sanhuang Oil were identified using UPLC-QE-Orbitrap-MS.Subsequently,the mechanism by which Sanhuang Oil promotes diabetic foot ulcer healing was predicted by integrating network pharmacology and molecular docking.Additionally,diabetic mouse model was established in ICR mice using a combination of a high-fat diet(HFD)and streptozotocin(STZ)chemical induction.A full-thickness skin defect was created on the dorsum of the mice.Wound healing and the healing rate were observed following Sanhuang Oil intervention.The mechanism underlying Sanhuang Oil’s promotion of diabetic ulcer healing was further investigated using transcriptomics and histopathological examination(H&E staining).Results:A total of 97 active ingredients were identified from Sanhuang Oil.Network pharmacology analysis predicted 543 common targets,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis identified 203 relevant pathways.Molecular docking further confirmed high binding affinity(binding energy≤−5.0 kcal/mol)between specific active components in Sanhuang Oil(e.g.,coptisine,phellodendrine,baicalein)and key targets associated with diabetic foot ulcers(e.g.,EGFR,AKT1,STAT3).In vivo experimental results demonstrated that the wound healing rate was significantly higher in Sanhuang Oil-treated groups compared to the model group(P<0.001).HE staining revealed that the high-dose Sanhuang Oil group exhibited more pronounced epithelial tissue coverage over the wound,reduced inflammatory cell infiltration,and increased collagen deposition and fibroblast proliferation.transcriptomic analysis identified Pdk4,Ttn,Csrp3,Actn2,Myoz2,Tnnc2,Myod1,Myog,Myot,and Myf6 as key regulatory proteins involved in promoting wound healing.Conclusion:Sanhuang Oil promotes wound healing in diabetic ulcer mice,potentially by mitigating inflammation and regulating key targets such as Pdk4 to enhance fibroblast function.These findings provide novel insights into the multi-target,multi-pathway mechanism of Sanhuang Oil for treating diabetic foot ulcers. 展开更多
关键词 Sanhuang Oil diabetic foot high-resolution mass spectrometry molecular network analysis mechanism of action
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Constructions of Control Sequence Set for Hierarchical Access in Data Link Network
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作者 Niu Xianhua Ma Jiabei +3 位作者 Zhou Enzhi Wang Yaoxuan Zeng Bosen Li Zhiping 《China Communications》 2026年第1期67-80,共14页
As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and ... As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities. 展开更多
关键词 control sequence data link hierarchical access control theoretical bound
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Genetic diversity and population structure of the Fujian oyster Crassostrea angulata revealed by mitochondrial COⅠgene and nuclear gene ITS2 sequences
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作者 Shiqi YU Ziqiang HAN Huayong QUE 《Journal of Oceanology and Limnology》 2026年第1期419-432,共14页
The Fujian oyster(Crassostrea angulata)is an economically significant shellfish species distributed mainly along the Fujian coast,Southeast China.However,its genetic diversity and structure remain unclear.The main dis... The Fujian oyster(Crassostrea angulata)is an economically significant shellfish species distributed mainly along the Fujian coast,Southeast China.However,its genetic diversity and structure remain unclear.The main distribution area of the C.angulata is located in Fujian,South China.In total,420 C.angulata were collected from 14 natural habitats(populations)along the Fujian coast,and their genetic diversity and structure were analyzed in the mitochondrial COⅠand nuclear gene ITS2 sequences.Results reveal that all the 14 populations of C.angulata exhibited high levels of genetic diversity,with a total of 57(haplotype diversity:0.811±0.016)and 124(haplotype diversity:0.912±0.007)haplotypes revealed by COⅠand ITS2,respectively.Notably,significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ)population(F_(ST)by COI:0.035-0.142,P<0.05;F_(ST)by ITS2:0.078-0.123,P<0.05)with other populations were observed for the first time,which is also supported by the results of molecular variance analysis(F_(CT)by COⅠ:0.105,P<0.05;F_(CT)by ITS2:0.086,P<0.05)and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree.Furthermore,the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations.In addition,the population dynamics analysis suggests that the C.angulata may have undergone expansion during the third ice age of the Pleistocene.These results provide a reference for the preservation and further genetic improvement of C.angulata. 展开更多
关键词 Crassostrea angulata genetic diversity population structure mitochondrial COⅠgene nuclear gene ITS2 sequence
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Robust Hyper-Polarization Protocol of Nuclear Spins via Magic Sequence
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作者 Haiyang Li Yongju Li +1 位作者 Hao Liao Ping Wang 《Chinese Physics Letters》 2026年第1期105-128,共24页
Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to thei... Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite half𝜋pulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center. 展开更多
关键词 transferring polarization electrons hyperpolarization protocols quantum information technologiesas nuclear spins pulse polarization nuclear spin polarization magic sequences nuclear magnetic resonance
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High-Resolution Transgressive-Regressive Sequence Stratigraphy of Chang 8 Member of Yanchang Formation in Southwestern Ordos Basin,Northern China 被引量:3
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作者 吕明胜 陈开远 +2 位作者 薛良清 衣丽萍 朱红涛 《Journal of Earth Science》 SCIE CAS CSCD 2010年第4期423-438,共16页
The reservoirs within the Chang 8 Member of Yanchang (延长) Formation in the south- western Ordos basin are characterized by low permeability. It is significant to build a high-resolution sequence stratigraphic fram... The reservoirs within the Chang 8 Member of Yanchang (延长) Formation in the south- western Ordos basin are characterized by low permeability. It is significant to build a high-resolution sequence stratigraphic framework for the exploration and development of these reservoirs. Based on an integrated investigation of well logs, seismic data, cores and outcrops, the Chang 8 Member is interpreted as a 3rd-order transgressive-regressive (T-R) sequence, which consists of six 4th-order T-R se- quences, namely, K1, K2, K3, K4, K5 and K6, respectively, from base to top. Each 4th-order sequence comprises a transgressive systems tract overlain by a regressive systems tract. From K1 to transgressive systems tract of K4, it is characterized by the landward shifts of facies and overall retrogradational sequence stacking pattern due to accommodation increase more than sediment supply during the 3rd-order base-level rise. The distributary channels are mainly deposited in the transgressive systems tracts, and the interdistributary bays, sheet sands, and small-scale mouth bars are primarily developed in the regressive systems tracts in response to the 4th-order base-level fluctuations. From the regressivesystems tracts of K4 to K6, it is characterized by the basinward shifts of facies and overall progradational sequence stacking pattern because of accommodation increase less than sediment sup- ply during a fall in 3rd-order base level. The distributary channels are mainly accumulated in the transgressive systems tracts, and distributary channels and mouth bars are deposited in the regressive systems tracts as a result of the 4th-order base-level changes. Detailed stratigraphic and sedimentoiogical analyses indicate that sequences K1, K2, K5 and K6, as well as the basin edge of K3 and K4, remain potential for exploration and development due to their high reservoir quality in response to the low accommodation and more sediment supply. 展开更多
关键词 transgressive-regressive sequence base level sediment supply sequence stratigraphicframework Ordos basin.
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HLA-A Gene Polymorphism Defined by High-Resolution Sequence-Based Typing in 161 Northern Chinese Han People 被引量:13
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作者 ChunxiaYan RuilinWang +11 位作者 JingxiangLi YajunDeng DongyingWu HongboZhang HongxingZhang LidongWang ChunrongZhang HaiyanSun XiuqingZhang JianWang HuanmingYang ShengbinLi 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2003年第4期304-309,共6页
Human leukocyte antigen (HLA) system is the most polymorphic region known in the human genome. In the present study, we analyzed for the first time the HLA-A gene polymorphisms defined by the high-resolution typing me... Human leukocyte antigen (HLA) system is the most polymorphic region known in the human genome. In the present study, we analyzed for the first time the HLA-A gene polymorphisms defined by the high-resolution typing methods-sequence-based typing (SBT) in 161 Northern Chinese Han people. A total of 74 different HLA-A gene types and 36 alleles were detected. The most frequent alleles were A*110101 (GP=0.2360), A*24020101 (GF=0.1646), and A*020101 (GF=0.1553); followed by A*3303 (GF=0.1180), A*3001 (GF=0.0590), and A*310102 (GF=0.0404). The frequencies of following alleles, A*0203, A*0205, A*0206, A*0207, A*030101, A*2423, A*2601, A*3201, and A*3301, are all higher than 0.0093. The homozygous alleles include A*020101, A*110101, A*24020101 and A*310102. Heterozygosity (H), polymorphism information content (PIC), discrimination power (DP) and probability of paternity exclusion (PPE) of HLA-A in the samples were calculated and their values were 0.8705, 0.8491, 0.6014, and 0.9475, respectively. These results by SBT analysis of HLA-A polymorphism in Northern Chinese Han population, especially the allele subtypes character, will be of great interest for clinical transplantation, disease-associated study and forensic identification. Implementation of high-resolution typing methods allows a significantly wider spectrum of HLA variation including rare alleles. This spectrum will further be extensively utilized in many fields. 展开更多
关键词 HLA-A POLYMORPHISM sequence-based typing (SBT) Han population
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Combining machine learning algorithms with traditional methods for resolving the atomic-scale dynamic structure of monolayer MoS_(2) in high-resolution transmission electron microscopy 被引量:1
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作者 Yu Meng Shuya Wang +5 位作者 Xibiao Ren Han Xue Xuejun Yue Chuanhong Jin Shanggang Lin Fang Lin 《Chinese Physics B》 2025年第1期162-170,共9页
High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-co... High-resolution transmission electron microscopy(HRTEM)promises rapid atomic-scale dynamic structure imaging.Yet,the precision limitations of aberration parameters and the challenge of eliminating aberrations in Cs-corrected transmission electron microscopy constrain resolution.A machine learning algorithm is developed to determine the aberration parameters with higher precision from small,lattice-periodic crystal images.The proposed algorithm is then validated with simulated HRTEM images of graphene and applied to the experimental images of a molybdenum disulfide(MoS_(2))monolayer with 25 variables(14 aberrations)resolved in wide ranges.Using these measured parameters,the phases of the exit-wave functions are reconstructed for each image in a focal series of MoS_(2)monolayers.The images were acquired due to the unexpected movement of the specimen holder.Four-dimensional data extraction reveals time-varying atomic structures and ripple.In particular,the atomic evolution of the sulfur-vacancy point and line defects,as well as the edge structure near the amorphous,is visualized as the resolution has been improved from about 1.75?to 0.9 A.This method can help salvage important transmission electron microscope images and is beneficial for the images obtained from electron microscopes with average stability. 展开更多
关键词 aberration measurement high-resolution transmission electron microscopy feature-extraction networks exit-wave reconstruction monolayer MoS_(2)
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PLC transition sequence identification based on logical reduction 被引量:1
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作者 Yue Luo Jianhong Ye +2 位作者 Jiazhong Zhou Jia Liu Linping Jiang 《Control Theory and Technology》 2025年第4期672-687,共16页
In industrial control systems,such as power transmission facilities and water treatment plants,Programmable Logic Controllers(PLCs)can work consistently and stably over long periods if there are no faults.Black-box id... In industrial control systems,such as power transmission facilities and water treatment plants,Programmable Logic Controllers(PLCs)can work consistently and stably over long periods if there are no faults.Black-box identification aims to automatically construct Petri net models with the help of I/O signals from PLC devices only.The main challenge is how to convert the infinitely long PLC signals into an event sequence,which is the foundation for subsequent modeling.The current algorithms are confronted with a number of challenges,including an exponential increase in the number of transitions,high time complexity,and susceptibility to noisy signals.To solve these problems,this paper proposes a new method for converting PLC signals into a transition sequence.The method is based on the principles of Boolean absorption law,which filters out noise information in the I/O signals.Then firing functions representing input–output causality are constructed from the filtered signals.Finally,the original signal sequence is traversed to generate a transition sequence.The experimental results show that these methods can rapidly identify a transition sequence.Compared to traditional methods,the proposed algorithms have polynomial time complexity. 展开更多
关键词 PLC Boolean logic Transition sequence Petri net
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