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Petrogenesis of the Late Eocene to Early Oligocene Yao'an Shoshonitic Complex,Southeastern Tibet:Partial Melting of an Ancient Continental Lithospheric Mantle beneath the Yangtze Block 被引量:2
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作者 DONG Mengmeng YANG Tiannan +3 位作者 XUE Chuandong XIN Di LIANG Mingjuan YAN Qinggao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1657-1670,共14页
Cenozoic potassic-ultrapotassic igneous rocks are widespread in the southeastern Tibetan Plateau.Their petrogenesis and magmatic processes remain subject to debate in spite of numerous publications.Almost all of the C... Cenozoic potassic-ultrapotassic igneous rocks are widespread in the southeastern Tibetan Plateau.Their petrogenesis and magmatic processes remain subject to debate in spite of numerous publications.Almost all of the Cenozoic extrusive and intrusive rocks in the Yao’an area,western Yunnan Province,SW China,are geochemically shoshonitic,collectively termed here the Yao’an Shoshonitic Complex(YSC).The YSC is located in the(south)easternmost part of the ENE-WSW-trending,~550 km-long and~250 km-wide Cenozoic magmatic zone;the latter separates the orthogonal and oblique collision belts of the India-Eurasia collision orogen.Previously published geochronological and thermochronological data revealed that the rocks of the YSC were emplaced over a short timespan of 34-32 Ma.This and our new data suggest that the primary magma of the YSC likely was formed by partial melting of ancient continental lithospheric mantle beneath the Yangtze Block.This part of the continental lithospheric mantle had likely not been modified by any oceanic subduction.Fractionation crystallization of an Mg-and Ca-bearing mineral and TiFe oxides during the magmatic evolution probably account for the variable lithologies of the YSC. 展开更多
关键词 Ancient continental lithospheric mantle Partial melting Yao’an Shoshonitic Complex Late Eocene to early oligocene SE Tibetan Plateau
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Diagenetic evolution and reservoir quality of the Oligocene sandstones in the Baiyun Sag, Pearl River Mouth Basin, South China Sea
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作者 Bing Tian Shanshan Zuo +3 位作者 Youwei Zheng Jie Zhang Jiayu Du Jun Tang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期67-82,共16页
The Oligocene Zhuhai sandstones are significant reservoirs for hydrocarbons in the Baiyun Sag, South China Sea.For effective appraisal, exploration and exploitation of such a deep-water hydrocarbon sandstone, samples ... The Oligocene Zhuhai sandstones are significant reservoirs for hydrocarbons in the Baiyun Sag, South China Sea.For effective appraisal, exploration and exploitation of such a deep-water hydrocarbon sandstone, samples of five wells from depths of 850 m to 3 000 m were studied. A series of comprehensive petrographic and geochemical analyses were performed to unravel the diagenetic features and their impact on the reservoir quality.Petrographically, the sandstones are dominated by feldspathic litharenites and lithic arenites with fine to medium grain sizes and moderate to good sorting. The reservoir quality varies greatly with a range of porosity from 0.2% to 36.1% and permeability from 0.016 ×10~(–3) μm~2 to 4 301 ×10~(–3) μm~2, which is attributed to complex diagenetic evolution related to sedimentary facies;these include compaction, cementation of calcite, dolomite, siderite and framboidal pyrite in eogenetic stage;further compaction, feldspar dissolution, precipitation of ferrocalcite and ankerite, quartz cements, formation of kaolinite and its illitization, precipitation of albite and nodular pyrite, as well as hydrocarbon charge in mesogenetic stage. The dissolution of feldspar and illitization of kaolinite provide internal sources for the precipitation of quartz cement, while carbonate cements are derived from external sources related to interbedded mudstones and deep fluid. Compaction is the predominant factor in reducing the total porosity, followed by carbonate cementation that leads to strong heterogeneity. Feldspar dissolution and concomitant quartz and clay cementation barely changes the porosity but significantly reduces the permeability.The high-quality reservoirs can be concluded as medium-grained sandstones lying in the central parts of thick underwater distributary channel sandbodies(>2 m) with a high content of detrital quartz but low cement. 展开更多
关键词 Baiyun Sag oligocene Zhuhai Formation DIAGENESIS reservoir quality
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Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications
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作者 Tao Yang Jia-Hao Cai +9 位作者 Yan-Zhi Dai Hong-Yu Chen Lei Han Li Zhang Wei-Yu Liang Xu-Jun Li Wen-Jia Li Jing-Yu Wu San-Ping Xie De-Fei Yan 《Plant Diversity》 SCIE CAS CSCD 2024年第1期101-115,共15页
Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant fossils.The Qaidam Basin has long been regarded as an ideal‘field laboratory’to investiga... Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant fossils.The Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan Plateau.However,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is poor.Here,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus grandis.These findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the Oligocene.The northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late Paleogene.This floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic conditions.Indeed,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene. 展开更多
关键词 PALEOENVIRONMENT BIOGEOGRAPHY Betulaceous fossil Qaidam basin Tibetan Plateau oligocene
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Aliphatic biomarker signatures of early Oligocene-early Miocene source rocks in the central Qiongdongnan Basin:Source analyses of organic matter
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作者 Min Xu Dujie Hou +4 位作者 Xiong Cheng Jun Gan Xinde Xu Gang Liang Wenjing Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第3期1-18,共18页
The geochemical signatures of fifty-four rock samples and three supplementary drill stem test(DST)oils from the Yacheng-Sanya formations in the central Qiongdongnan Basin(CQB)were analysed.Reconstruction of the early ... The geochemical signatures of fifty-four rock samples and three supplementary drill stem test(DST)oils from the Yacheng-Sanya formations in the central Qiongdongnan Basin(CQB)were analysed.Reconstruction of the early Oligocene-early Miocene(36–16 Ma)palaeovegetation and source analyses of organic matter(OM)were conducted using aliphatic biomarkers in ancient sediments and DST oils.Both the interpreted aquatic and terrigenous OM contributed to the CQB source rocks(SRs)but had varying relative proportions.The four distribution patterns derived from n-alkanes,terpanes,and steranes are representative of four OM composition models of the Yacheng-Sanya SRs,including model A,model B,model C,and model D,which were classified based on the increasing contribution from terrigenous OM relative to aquatic OM.Some terrigenous higher plantderived biomarkers,including oleanane,des-A-oleanane,C_(29)ααα20R sterane,bicadinanes,the C_(19)/(C_(19)+C_(23))tricyclic terpane ratio,and other n-alkane-derived ratios suggest that angiosperms had increased proportions in the palaeoflora from early Oligocene to early Miocene,and the bloom of terrigenous higher plants was observed during deposition of upper Lingshui Formation to lower Sanya Formation.These findings are consistent with the incremental total organic carbon and free hydrocarbons+potential hydrocarbons(S_1+S_2)in the lower Lingshuilower Sanya strata with a significant enrichment of OM in the E_3l_1-N_1s_2 shales.The maturity-and environmentsensitive aliphatic parameters of the CQB SRs and DST oils suggest that all the samples have predominantly reached their early oil-generation windows but have not exceeded the peak oil windows,except for some immature Sanya Formation shales.In addition,most of the OM in the analysed samples was characterised by mixed OM contributions under anoxic to sub-anoxic conditions.Furthermore,terrestrial-dominant SRs were interpreted to have developed mainly in the Lingshui-Sanya formations and were deposited in sub-oxic to oxic environments,compared to the anoxic to sub-anoxic conditions of the Yacheng Formation. 展开更多
关键词 aliphatic biomarkers early oligocene-early Miocene organic matter sources palaeovegetation reconstruction Qiongdongnan Basin
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Paleoclimate Changes during the Early Oligocene in the Hoh Xil Region, Northern Tibetan Plateau 被引量:8
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作者 LIUZhifei WANGChengshan +4 位作者 AlainTRENTESAUX ZHAOXixi YIHaisheng HUXiumian JINWei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第4期504-513,共10页
Sedimentological, cyclic-stratigraphic, paleomagnetic, and clay-mineralogical studies on the early Oligocene Yaxicuo Group in the Hoh Xil Basin, the largest Cenozoic sedimentary basin in the hinterland of the Tibetan ... Sedimentological, cyclic-stratigraphic, paleomagnetic, and clay-mineralogical studies on the early Oligocene Yaxicuo Group in the Hoh Xil Basin, the largest Cenozoic sedimentary basin in the hinterland of the Tibetan Plateau, provide abundant information of paleoclimate changes. A 350-m thick section in the middle-lower Yaxicuo Group was analyzed to reveal the climatic history that occurred in the Hoh Xil region during the early Oligocene interval 31.30-30.35 Ma, dated with the paleomagnetic chronostratigraphy. The results indicate that arid and cold climate dominated the Hoh Xil region during the early Oligocene in general, being related to the global cooling and drying events that occurred in the earliest Oligocene. Within this period, relatively warm and wet climate accompanied by strong tectonic activity occurred in the 31.05-30.75 Ma interval; while arid and cold climate and relatively inactive tectonics occurred in the 31.30-31.05 and 30.75-30.35 Ma intervals. Furthermore, spectral analyses of high-temporal resolution paleoclimatic records show orbital periods including eccentricity, obliquity, and precession. It is concluded that paleoclimate changes during the early Oligocene in the Hoh Xil region were forced by both tectonic activity and orbital periods. 展开更多
关键词 climate changes early oligocene Hoh Xil Basin Tibetan Plateau tectonic forcing astronomical periods
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Petrogenesis of Oligocene volcanic rocks of the Lake Tana area,Ethiopian large Igneous Province
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作者 Ayenachew Alemayhou Desta Asfawossen Asrat Minyahl Teferi Desta 《Acta Geochimica》 EI CAS CSCD 2023年第6期1104-1123,共20页
The Lake Tana area is located within a complex volcano-tectonic basin on the northwestern Ethiopian plateau.The basin is underlain by a thick succession of Oligocene transitional basalts and sub-alkaline rhyolites ove... The Lake Tana area is located within a complex volcano-tectonic basin on the northwestern Ethiopian plateau.The basin is underlain by a thick succession of Oligocene transitional basalts and sub-alkaline rhyolites overlain in places,particularly south of the lake,by Quaternary alkaline to mildly transitional basalts,and dotted with Oligo-Miocene trachyte domes and plugs.This paper presents the results of integrated field,petrographic,and major and trace element geochemical studies of the Lake Tana area volcanic rocks,with particular emphasis on the Oligocene basalts and rhyolites.The studies reveal a clear petrogenetic link between the Oligocene basalts and rhyolites.The Oligocene basalts are:(1)plagioclase,olivine,and/or pyroxene phyric;(2)show an overall decreasing trend in MgO,Fe_(2)O_(3),and CaO with silica;(3)have relatively low Mg#,Ni and Cr contents and high Nb/La and Nb/Yb ratios;and(4)show LREE enriched and generally flat HREE patterns.All these imply the origin of the Oligocene basalts by shallow-level fractional crystallization of an enriched magma sourced at the asthenospheric mantle.The Oligocene rhyolites:(1)are enriched in incompatible while depleted in compatible trace elements,P and Ti;(2)show a strong negative Eu anomaly;(3)contain appreciable amounts of plagioclase,apatite,and Fe-Ti oxides;and(4)show clear geochemical similarity with well-constrained rhyolites from the Large Igneous Province(LIP)of the northwestern Ethiopian plateau.Low-pressure fractional crystallization of mantle-derived basaltic magma in crustal magma chambers explains the origin of these rhyolites.Our study further shows that the Oligocene basalts and rhyolites are co-genetic and the felsic rocks of the Lake Tana area are related differentiates of the flood basalt volcanism in the northwestern Ethiopian plateau. 展开更多
关键词 Large igneous province oligocene basalt oligocene rhyolite Fractional crystallization Lake Tana
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Late Oligocene fossil acorns and nuts of Quercus section Cyclobalanopsis from the Nanning Basin,Guangxi,South China
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作者 Xiao-Yan Liu Han-Zhang Song +4 位作者 Xin-Kai Wu Jia-Rong Hu Wei-Ye Huang Cheng Quan Jian-Hua Jin 《Plant Diversity》 SCIE CAS CSCD 2023年第4期434-445,共12页
Quercus is the largest genus within the Fagaceae and has a rich fossil record.Most of the fossil material is attributed to the subgenus Quercus based on leaves,pollen or rarely acorns and nuts.Fossil records of Q.sect... Quercus is the largest genus within the Fagaceae and has a rich fossil record.Most of the fossil material is attributed to the subgenus Quercus based on leaves,pollen or rarely acorns and nuts.Fossil records of Q.section Cyclobalanopsis characterized by ring-cupped acorns are relatively few and especially those described based on nuts are scant.In this study,we described four new species of Quercus section Cyclobalanopsis based on mummified acorns and nuts:Q.paleodisciformis X.Y.Liu et J.H.Jin sp.nov.,Q.paleohui X.Y.Liu et J.H.Jin sp.nov.,Q.nanningensis X.Y.Liu et J.H.Jin sp.nov.and Q.yongningensis X.Y.Liu et J.H.Jin sp.nov.These species closely resemble the extant species Q.disciformis,Q.hui,Q.kerrii,and Q.dinghuensis.The occurrence of Q.section Cyclobalanopsis in the Oligocene stratum of Guangxi,South China,suggests that the section has diversified within its extant distribution center since the Oligocene.By combining records from other areas,we propose that the section first appeared in the middle Eocene of East Asia(Sino-Japan),has diversified in situ with a few elements scattering into West Asia and southern Europe since the Oligocene and Pliocene,respectively,and finally became restricted in East Asia since the Pleistocene.This indicates that the section originated and diversified in East Asia,before spreading into West Asia no later than the Oligocene and into southern Europe by the Pliocene.Subsequently it disappeared from South Europe and West Asia due to the appearance of the(summer dry)Mediterranean climate and widespread cooling during the Pleistocene. 展开更多
关键词 Quercus section Cyclobalanopsis Fossil acorn and nut oligocene GUANGXI South China
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Early Treatment Outcome of Humeral Shaft Fracture Non-Union in Adults: Comparative Study of Plating versus Interlocking Nailing
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作者 Abdullallahi Bello Galadima Lukman Olalekan Ajiboye +1 位作者 Muhammad Nuhu Salihu Isha Nurudeen 《Health》 2024年第4期371-381,共11页
Background: Fractures of humeral shaft in adults are common injuries. Humeral shafts non-union either from late presentation after initial treatment by traditional bone setters or failed non-operative orthodox care is... Background: Fractures of humeral shaft in adults are common injuries. Humeral shafts non-union either from late presentation after initial treatment by traditional bone setters or failed non-operative orthodox care is a major problem in this part of the world. This non-union is a major treatment challenge with increased cost of care and morbidity in this part of the world. Humeral shaft non-union can be treated with locked intra-medullary nailing (LIMN) or dynamic compression plating (DCP). Study on comparison of these methods of fixation in this part of the world is scarce in literature search, hence the reason for this study. Objective: The objectives of this study are: (1) to compare early clinical outcome following fixation of humeral shaft fracture nonunion with DCP versus LIMN;(2) to compare the time of radiologic fracture union of DCP with LIMN;(3) to compare complications following fixation of humeral shaft fracture nonunion with DCP versus LIMN. Patients and Methods: This was a randomized control study done for 2 years in which fifty adult patients with humeral shaft non-union were recruited. The patients were grouped into 2 (P = DCP & N = LIMN). Forty five of the patients completed the follow up periods of the study and then analyzed. The P group had ORIF with DCP while the N group had ORIF with LIMN. Both groups had grafting with cancellous bones. Each patient was followed up for a period of 6 months at the time which radiographic union is expected. Any patient without clinical and/or radiographic evidence of union after six months of surgery was diagnosed as having recurrent non-union. The data generated was analyzed using SPSS Version 23. The results were presented in charts and tables. The paired t-test was used while considering p value Result: Forty five patients completed follow up. There was a male preponderance (4:1), right humerus predominated (3:2). Motor vehicular accidents were the commonest cause of the fractures (62%). Most non-union fractures occurred at the level of the middle 3<sup>rd</sup> of the humeral shaft (60%). Failed TBS treatment was the commonest indication for the osteosynthesis (71%). More patients had plating (53%) compared to 47% who had LIMN. Most patients (93.4%) had union between 3 to 6 months irrespective of fixation type with no significant statistical difference between the union rate of DCP and LIMN (p value 0.06) with similar functional outcome and complication rates irrespective of the type of fixation. Conclusion: This study showed that the success rates in term of fracture union, outcome functional grades and complication rates were not directly dependent on the types of the fixation: plating or locked intra-medullary nailing. 展开更多
关键词 Humeral Shaft NON-UNION Dynamic Compression Plating Locked Intra-Medullary Nailing early Treatment Outcome early Outcome
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Characteristics of early gastric tumors with different differentiation and predictors of long-term outcomes after endoscopic submucosal dissection
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作者 Hong-Yi Zhu Jie Wu +7 位作者 Yuan-Miao Zhang Fang-Lan Li Jin Yang Bin Qin Jiong Jiang Ning Zhu Meng-Yao Chen Bai-Cang Zou 《World Journal of Gastroenterology》 SCIE CAS 2024年第14期1990-2005,共16页
BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological char... BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological characteristics of gastric mucosal tumors with different differentiation degrees and the influencing factors of long-term ESD efficacy may have certain significance for revealing the development of gastric cancer and ESD.AIM To analyze the features of gastric mucosal tumors at different differentiation levels,and to explore the prognostic factors of ESD.METHODS We retrospectively studied 301 lesions in 285 patients at The Second Affiliated Hospital of Xi'an Jiaotong University from 2014 to 2021,according to the latest Japanese guidelines(sixth edition),and divided them into low-grade intrae-pithelial neoplasia(LGIN),high-grade intraepithelial neoplasia(HGIN),and computed tomography at 3,6 and 12 months after ESD.We compared clinicopathologic characteristics,ESD efficacy,and complications with different degrees of differentiation,and analyzed the related factors associated with ESD.RESULTS HGIN and differentiated carcinoma patients were significantly older compared with LGIN patients(P<0.001)and accounted for more 0-IIc(P<0.001),atrophic gastritis was common(P<0.001),and irregular microvascular patterns(IMVPs)and demarcation lines(DLs)were more obvious(P<0.001).There was more infiltration in the undifferentiated carcinoma tissue(P<0.001),more abnormal folds and poorer mucosal peristalsis(P<0.001),and more obvious IMVPs,irregular microsurface patterns and DLs(P<0.05)than in the LGIN and HGIN tissues.The disease-free survival rates at 2,5,and 8 years after ESD were 95.0%,90.1%,and 86.9%,respectively.Undifferen-tiated lesions(HR 5.066),white moss(HR 7.187),incomplete resection(HR 3.658),and multiple primary cancers(HR 2.462)were significantly associated with poor prognosis.CONCLUSION Differentiations of gastric mucosal tumors have different epidemiological and endoscopic characteristics,which are closely related to the safety and efficacy of ESD. 展开更多
关键词 Gastric mucosal epithelial neoplasia Differentiated early gastric cancer Undifferentiated early gastric cancer Endoscopic submucosal dissection Long-term outcomes
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Arlenea delicata gen.et sp.nov.,a new ephedroid plant from the Early Cretaceous Crato Formation,Araripe Basin,Northeast Brazil
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作者 Alita Maria Neves Ribeiro Yong Yang +3 位作者 Antonio Alamo Feitosa Saraiva Renan Alfredo Machado Bantim Joao Tavares Calixto Junior Flaviana Jorge de Lima 《Plant Diversity》 SCIE CAS CSCD 2024年第3期362-371,共10页
Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE China.However,few ephedroid macrofossils have been reported from South Amer... Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE China.However,few ephedroid macrofossils have been reported from South America.Herein,we describe a new plant of the family Ephedraceae,Arlenea delicata gen.et sp.nov.,from the Lower Cretaceous Crato Formation of the Araripe Basin,Northeast Brazil,based on the vegetative and reproductive structures.It has the typical morphological characteristics of ephedroid plants,including fertile reproductive branches,opposite phyllotaxy,terminal female cones,a sympodial branching system,longitudinally striated internodes,and swollen nodes.Our new finding is unusual in having inner chlamydosperms subtended by two pairs of bracts,reproductive units connected to branches through swollen receptacles and a smooth seed surface.This new ephedroid taxon from the Crato Formation increases our understanding of plant diversity of this group during the Early Cretaceous.Furthermore,the general morphology(fleshy bracts and enlarged receptacles)of this new fossil discovery indicates that seeds of this plant may have been dispersed by animals such as pterosaurs(mainly the Tapejaridae)and birds(Enantiornithes and Ornituromorpha).If true,this would explain the cosmopolitan distribution of Ephedraceae in the Lower Cretaceous. 展开更多
关键词 early Cretaceous Gnetophytes Arlenea delicata Ephedrales Crato Formation
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Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite
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作者 YANG Zhen FU Yong +2 位作者 LI Chao CAI Xi GUO Chuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期416-429,共14页
A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differ... A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite.The results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan profile.The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional environments.The sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from seawater.Overall,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid. 展开更多
关键词 sedimentary environment black shale polymetallic layer PYRITE early Cambrian
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Early identification of stroke through deep learning with multi-modal human speech and movement data
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作者 Zijun Ou Haitao Wang +9 位作者 Bin Zhang Haobang Liang Bei Hu Longlong Ren Yanjuan Liu Yuhu Zhang Chengbo Dai Hejun Wu Weifeng Li Xin Li 《Neural Regeneration Research》 SCIE CAS 2025年第1期234-241,共8页
Early identification and treatment of stroke can greatly improve patient outcomes and quality of life.Although clinical tests such as the Cincinnati Pre-hospital Stroke Scale(CPSS)and the Face Arm Speech Test(FAST)are... Early identification and treatment of stroke can greatly improve patient outcomes and quality of life.Although clinical tests such as the Cincinnati Pre-hospital Stroke Scale(CPSS)and the Face Arm Speech Test(FAST)are commonly used for stroke screening,accurate administration is dependent on specialized training.In this study,we proposed a novel multimodal deep learning approach,based on the FAST,for assessing suspected stroke patients exhibiting symptoms such as limb weakness,facial paresis,and speech disorders in acute settings.We collected a dataset comprising videos and audio recordings of emergency room patients performing designated limb movements,facial expressions,and speech tests based on the FAST.We compared the constructed deep learning model,which was designed to process multi-modal datasets,with six prior models that achieved good action classification performance,including the I3D,SlowFast,X3D,TPN,TimeSformer,and MViT.We found that the findings of our deep learning model had a higher clinical value compared with the other approaches.Moreover,the multi-modal model outperformed its single-module variants,highlighting the benefit of utilizing multiple types of patient data,such as action videos and speech audio.These results indicate that a multi-modal deep learning model combined with the FAST could greatly improve the accuracy and sensitivity of early stroke identification of stroke,thus providing a practical and powerful tool for assessing stroke patients in an emergency clinical setting. 展开更多
关键词 artificial intelligence deep learning DIAGNOSIS early detection FAST SCREENING STROKE
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Determinants of Early Survival of Breast Cancer Patients in Yaoundé-Cameroon
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作者 Um Esther Meka Ngo Junie Annick Metogo Ntsama +4 位作者 Kodoumé Motolouze Naomi Marie Laurene Ndtoungou Schouame Obalemba Etienne Atenguena Claude Cyrille Noa Ndoua Robinson Enow Mbu 《Open Journal of Obstetrics and Gynecology》 2024年第3期487-501,共15页
Introduction: Breast cancer is one of the leading causes of death worldwide. We carried out this study with the aim of evaluating the determinants of early survival of women with breast cancer in two hospitals in the ... Introduction: Breast cancer is one of the leading causes of death worldwide. We carried out this study with the aim of evaluating the determinants of early survival of women with breast cancer in two hospitals in the city of Yaoundé. Methodology: This was an analytical cross-sectional study with retrospective and prospective data collection of breast cancer patients during 6 years in two Hospitals of Yaoundé from January 2017 to December 2022. We consulted the files in search of epidemiological, clinical, paraclinical, therapeutic and survival variables. We completed the survival data directly from the patients or their relatives after their consent. We analyzed the data using SPSS version 23.0 software. Survival analysis was done using the Kaplan-Meier method and survival curves were compared using the Log Rank test. Factors influencing survival were evaluated using the Cox model. The significance threshold (P value) was set at 0.05 at 95% confidence interval. The study was approved by the ethics committees. Results: We included 500 patients whose ages varied between 22 and 83 years with a mean age of 47.19 ± 11.61 years. The most represented age group was 30 to 45 years old (45.8%). Less than half (41.6%) were postmenopausal. The most frequent reason for consultation was a breast lump (79.9%). The most common clinical stage at presentation was stage-3 (47.6%). Infiltrating ductal carcinoma was the most represented histological type (84.7%). The most represented histological grade was grade 2 (40.2%). Immunohistochemistry was performed in 34.20% of cases. The most represented molecular subtype was triple negative (41.8%) followed by Luminal A (30%). Concerning treatment, 17.2% did not receive any, 45% had surgery, 79.4% had chemotherapy, 34.2% hormone therapy, and 14.6% radiotherapy. The survival of patients with breast cancer at 1, 2, 3, 4 and 5 years was respectively 90.6%;83.1%;74.2%;69.8% and 59.2%. The median survival was not reached;however, the first quartile (Q1) was 36 months (3 years). Independent factors associated with reduced survival were breast ulceration (aHR = 3.23;p = 0.002), bilateral tumor location (aHR = 9.2;p < 0.001) and clinical stage 3 (aHR = 1.72;p = 0.010) while patients classified ACR3 on imaging (aHR = 0.19;p = 0.005) had improved survival. Conclusion: Breast cancer survival from 1 to 5 years decrease from 90 to 59%. Mortality was highest in the first 40 months. Independent factors associated with reduced survival were breast ulceration, bilateral tumor location and clinical stage 3 while patients classified ACR3 on imaging had improved survival. 展开更多
关键词 Determinants early Survival Breast Cancer Yaoundé
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Early Nursing Intervention in Children with Viral Meningitis
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作者 Jingyan Wang Qiuyan Peng +6 位作者 Haomei Yang Jing Sun Xian Cai Xiulan Wen Congqun Li Yan Lin Xuan Shi 《Journal of Behavioral and Brain Science》 2024年第1期1-11,共11页
Aim: To explore the effect of a WeChat peer education program in children with severe viral meningitis combined with respiratory failure. Design: Retrospective cohort study. Methods: Patients who had severe viral meni... Aim: To explore the effect of a WeChat peer education program in children with severe viral meningitis combined with respiratory failure. Design: Retrospective cohort study. Methods: Patients who had severe viral meningitis combined with respiratory failure, were admitted to the hospital from March 2017 to June 2018, and who received the WeChat-based nursing intervention were included. Patients who received routine nursing were used as controls. The family’s emotional state, self-care ability, and rehabilitation were analyzed. Results: There were 37 patients in the WeChat group (19 boys (51.3%) and 18 girls (48.7%);mean of 5.1 ± 2.4 years of age) and 37 controls (20 boys (54.1%) and 17 girls (45.9%);mean of 5.9 ± 2.4 years of age) (all P > 0.05). After nursing, improvements in the self-assessed anxiety score and self-assessed depression score were better in the WeChat group (anxiety: -29.2% vs. -20.3%, P = 0.015;depression: -25.2% vs. -15.4%, P = 0.009). After nursing, the improvements in the condition management ability scale and condition management difficulty scale scores were better in the WeChat group (ability: +80.5% vs. +44.4%. P = 0.001;difficulty: +58.4% vs. +37.8%, P = 0.003). After nursing, the improvement in the Fugl-Meyer score was better in the WeChat group (+138.0% vs. +53.0%, P Conclusion: Early nursing intervention combined with WeChat peer education can improve the emotional state of children with severe viral meningitis combined with respiratory failure and their caregivers. Impact: Viral meningitis is associated with a good prognosis, but central nervous system complications can be observed. Early intervention is the key to a good prognosis. Internet-based nursing and coaching can improve self-efficacy and care ability in patients with various conditions, as well as improve the emotional state of the children and their caregivers. The research might have an impact on any children’s hospital that deals with viral meningitis. 展开更多
关键词 Societies NURSING early Intervention EDUCATIONAL MENINGITIS VIRAL CHILD
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Early monitoring values of oncogenic signalling molecules for hepatocellular carcinoma
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作者 Min Yao Rong-Fei Fang +3 位作者 Qun Xie Min Xu Wen-Li Sai Deng-Fu Yao 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2350-2361,共12页
The prevention and early diagnosis of liver cancer remains a global medical challenge.During the malignant transformation of hepatocytes,a variety of oncogenic cellular signalling molecules,such as novel high mobility... The prevention and early diagnosis of liver cancer remains a global medical challenge.During the malignant transformation of hepatocytes,a variety of oncogenic cellular signalling molecules,such as novel high mobility group-Box 3,angiopoietin-2,Golgi protein 73,glypican-3,Wnt3a(a signalling molecule in the Wnt/β-catenin pathway),and secretory clusterin,can be expressed and secreted into the blood.These signalling molecules are derived from different signalling pathways and may not only participate in the malignant transformation of hepatocytes but also become early diagnostic indicators of hepatocarcinogenesis or specific targeted molecules for hepatocellular carcinoma therapy.This article reviews recent progress in the study of several signalling molecules as sensitive biomarkers for monitoring hepatocarcinogenesis. 展开更多
关键词 HEPATOCARCINOGENESIS Cell signals Specific biomarkers early diagnosis
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Effect of preload forces on multidimensional signal dynamic behaviours for battery early safety warning
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作者 Kuijie Li Jiahua Li +10 位作者 Xinlei Gao Yao Lu Depeng Wang Weixin Zhang Weixiong Wu Xuebing Han Yuan-cheng Cao Languang Lu Jinyu Wen Shijie Cheng Minggao Ouyang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期484-498,共15页
Providing early safety warning for batteries in real-world applications is challenging.In this study,comprehensive thermal abuse experiments are conducted to clarify the multidimensional signal evolution of battery fa... Providing early safety warning for batteries in real-world applications is challenging.In this study,comprehensive thermal abuse experiments are conducted to clarify the multidimensional signal evolution of battery failure under various preload forces.The time-sequence relationship among expansion force,voltage,and temperature during thermal abuse under five categorised stages is revealed.Three characteristic peaks are identified for the expansion force,which correspond to venting,internal short-circuiting,and thermal runaway.In particular,an abnormal expansion force signal can be detected at temperatures as low as 42.4°C,followed by battery thermal runaway in approximately 6.5 min.Moreover,reducing the preload force can improve the effectiveness of the early-warning method via the expansion force.Specifically,reducing the preload force from 6000 to 1000 N prolongs the warning time(i.e.,227 to 398 s)before thermal runaway is triggered.Based on the results,a notable expansion force early-warning method is proposed that can successfully enable early safety warning approximately 375 s ahead of battery thermal runaway and effectively prevent failure propagation with module validation.This study provides a practical reference for the development of timely and accurate early-warning strategies as well as guidance for the design of safer battery systems. 展开更多
关键词 Lithium-ion battery Thermal runaway Preload force Expansionforce early warning Multidimensional signal
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Women Breast Cancer: Knowledge, Attitudes, Practices and Factors Associated with Early Screening in the Municipality of Abomey-Calavi in Benin in 2018
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作者 Stéphane Arold Bidossessi Senahoun Nicolas Hamondji Amegan +7 位作者 Mahougnon Hugues Serge Dohou Hermann Comlanvi Agbedjinou Lucresse Corine Fassinou Tècle Edwige Korogone Armand Ibikounle Dieudonné Fambo Joël Gamêlé Mikponhoué Christiane Tshabu Aguemon 《Open Journal of Epidemiology》 2024年第1期131-156,共26页
Background: Breast cancer is the dominant cancer in women in both developed and developing countries. The objective of this study was to assess the knowledge, attitudes, practices and factors associated with early bre... Background: Breast cancer is the dominant cancer in women in both developed and developing countries. The objective of this study was to assess the knowledge, attitudes, practices and factors associated with early breast cancer screening among women in the Municipality of Abomey-Calavi in Benin. Methods: This was a cross-sectional, descriptive, analytical study with prospective data collection from October 1 to 8, 2018, involving 1740 women in the Municipality of Abomey-Calavi, aged 18 years or older and selected by WHO four-stage random cluster sampling. Consenting women who were mentally competent, 18 years of age or older at the time of the survey, and residing continuously in the Municipality of Abomey-Calavi for the last six months prior to the survey were included. On the other hand, women who belonged to a breast cancer prevention service, women in whom secondary screening was noted, or non-consenting women were not included. The initial minimum size was estimated by the Schwartz formula with a cluster effect of k = 2. Information was collected by questionnaire survey, entered with Epidata 3.1. Fr and analyzed with R Studio 3.5.1. software. Results: The mean age of the women surveyed was 32.0 ± 11.5 years with a range of 18 and 71 years. Regarding knowledge, the clinical manifestation known by the majority of women was the presence of a nodule (68.50%). In the series, 1308 (75.17%) declared having heard about breast cancer once before, either on the radio, television or from friends and 726 (55.50%) had heard about breast cancer screening. Five hundred and twelve (70.52%) of the 726 who had heard of breast cancer said they knew that breast cancer could be screened earlier. Breast self-examination was the most cited screening method (67.58%). The disease is of natural origin according to 37.84% of them. Regarding attitudes and practices, the prevalence of early breast cancer screening was 12.93%, of which 11.67% declared that they had checked themselves to know whether they were carriers of the disease or not. The main means of the early screening used was breast self-examination (85.78%). Factors associated with early breast cancer screening found in multivariate analysis were age (≤50 years), education level (increasingly higher), marital status (married/coupled), place of residence (downtown), and socioeconomic level (average/high). Conclusion: The frequency of early breast cancer screening among women is still low in the municipality of Abomey-Calavi, although they have a good knowledge of the disease. This raises the need to strengthen awareness of early breast cancer screening. 展开更多
关键词 Breast Cancer early Screening KNOWLEDGE PRACTICES ATTITUDES Associated Factors
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Comparative Study of Early Neonatal Complications between the First and Second Twin during Twin Vaginal Deliveries at the Yaounde Gynaeco-Obstetric and Pediatric Hospital, and the Yaounde Central Hospital
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作者 Florent Ymele Fouelifack Felicite Nguefack +3 位作者 Patricia Bashir Kadidja Roosvelt Dongmo Tiodjou Jeanne Hortence Fouedjio Pascal Foumane 《Open Journal of Obstetrics and Gynecology》 2024年第3期381-392,共12页
Introduction: Twin birth is the expulsion of two fetuses and their appendages out of the woman’s reproductive tract. It’s a high-risk delivery because of the high frequency of maternal, fetal and neonatal complicati... Introduction: Twin birth is the expulsion of two fetuses and their appendages out of the woman’s reproductive tract. It’s a high-risk delivery because of the high frequency of maternal, fetal and neonatal complications. Few studies exist on the comparative prognoses of twins. Our objective was to compare early neonatal complications in first and second twins. Methods: We carried out a cross-sectional prospective study from January 2 to April 30, 2020 (4 months) at the Yaounde Gynaeco-Obstetric and Pediatric Hospital, and the Yaounde Central Hospital. Data collected were analyzed using IBM SPSS version 23. Descriptive statistics were done in frequencies and percentages, means and standard deviations. Paired-sample student's t-test were used to compare means. McNemar’s Chi-square and Ficher’s exact tests were used to compare proportions. Statistical significance was set at p-values less than 0.05. Results: Of a total of 2183 deliveries during the study period, 43 (1.96%) were twin vaginal deliveries. Among the 43 women, 41 consented to have their newborns participate in the study. Overall, APGAR scores were better for the first twins at the first (p = 0.004) and fifth (p = 0.031) minutes than for the second twins. Although both twins had complications and that there were 4 neonatal deads of the second twin, there was no relationship between studied complications and the rank of the twin (p = 0.310). Conclusion: As the APGAR score seemed to be better for first twins, clinicians should pay more attention during twin births, in order to improve the prognosis of the second twin. 展开更多
关键词 Comparison Vaginal Birth Rank of Twin early Neonatal Complications
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Present and future of new systemic therapies for early and intermediate stages of hepatocellular carcinoma
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作者 Juan Jose Urquijo-Ponce Carlos Alventosa-Mateu +3 位作者 Mercedes Latorre-Sánchez Inmaculada Castelló-Miralles Moisés Diago Hepatology Unit 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2512-2522,共11页
Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Not... Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Notwithstanding the current deployment of treatments with curative intent(liver resection/local ablation and liver transplantation)in early and intermediate stages,a high rate of HCC recurrence persists,underscoring a pivotal clinical challenge.Emergent systemic therapies(ST),particularly immunotherapy,have demonstrate promising outcomes in terms of increase overall survival,but they are currently bound to the advanced stage of HCC.This review provides a comprehensive analysis of the literature,encompassing studies up to March 10,2024,evaluating the impact of novel ST in the early and intermediate HCC stages,specially focusing on the findings of neoadjuvant and adjuvant regimens,aimed at increasing significantly overall survival and recurrence-free survival after a treatment with curative intent.We also investigate the potential role of ST in enhancing the downstaging rate for the intermediate-stage HCC initially deemed ineligible for treatment with curative intent.Finally,we critically discuss about the current relevance of the results of these studies and the encouraging future implications of ST in the treatment schedules of early and intermediate HCC stages. 展开更多
关键词 Hepatocellular carcinoma early stage Intermediate stage NEOADJUVANT ADJUVANT Systemic therapy
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Provenance of Conglomerate and Sandstone from Early Permian Shoushangou Formation in Xi Ujimqin,Inner Mongolia:Implications for Understanding Paleo-Asian Ocean Subduction
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作者 ZHANG Yingli GUO Xianqing MA Shouxian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期10-31,共22页
During the Late Carboniferous to Early Permian,a rift was formed by post-collisional extension after ocean closure or an island arc-related basin formed by Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin area.Never... During the Late Carboniferous to Early Permian,a rift was formed by post-collisional extension after ocean closure or an island arc-related basin formed by Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin area.Nevertheless,the closure time of the PAO is still under debate.Thus,to identify the origin of the PAO,the geochemistry and U-Pb age of zircons were analyzed for the extra-large deep marine,polymict clastic boulders and sandstones in the Shoushangou Formation within the basin.The analyses revealed magmatic activity and tectonic evolution.The conglomerates include megaclasts of granite(298.8±9.1 Ma)and granodiorite porphyry(297.1±3.1 Ma),which were deposited by muddy debris flow.Results of this study demonstrated that the boulders of granitoids have the geochemistry of typical I-type granite,characterized by low Zr+Nb+Ce+Y and low Ga/Al values.The granitoid boulders were formed in island arc setting,indicating the presence of arc magmatism in the area that is composed of the Late Carboniferous to Early Permian subduction-related granitoid in southern Xi Ujimqin.Multiple diagrams for determining sedimentary provenance using major and trace elements indicate that Shoushangou sediments originated from continental island arc-related felsic rocks.Detrital zircon U-Pb age cluster of 330–280 Ma was obtained,indicating input from granite,ophiolite,Xilin Gol complex,and Carboniferous sources to the south.The basin was geographically developed behind the arc during the Early Permian period because the outcropped intrusive rocks in the Late Carboniferous to Early Permian form a volcanic arc.The comprehensive analyses of source areas suggest that Shoushangou sediments developed in a backarc basin in response to the northward subduction of the PAO.The backarc basin and intrusive rocks,in addition to previously published Late Carboniferous to Early Permian magmatic rocks of arc unit in Xilin Gol,confirm the presence of an Early Permian trencharc-basin system in the region,represented by the Baolidao arc and Xi Ujimqin backarc basin.This study highlights the importance and potential of combined geochemical and geochronological studies of conglomerates and sandstone for reconstructing the geodynamic setting of a basin. 展开更多
关键词 provenance analysis backarc basin Shoushangou Formation early Permian Central Asian Orogenic Belt
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