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Multi-analytical characterization of Os Draconis:distinguishing authentic samples from fossilized specimens and counterfeits for improved authentication
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作者 Dong-Han Bai Lu Luo +5 位作者 Zi-Hao Zhang Zi Xing Remy Macdonald Shu-Min Chen Qiao-Chu Wang Zhi-Jie Zhang 《Traditional Medicine Research》 2026年第3期36-55,共20页
Background:Os Draconis is an important material in traditional Chinese medicine(TCM).However,its market is saturated with counterfeit products,and the limitations of current identification methods pose a serious threa... Background:Os Draconis is an important material in traditional Chinese medicine(TCM).However,its market is saturated with counterfeit products,and the limitations of current identification methods pose a serious threat to clinical effectiveness and drug safety.This study aims to establish a more accurate and comprehensive authentication system for Os Draconis.Methods:A comprehensive approach was employed to analyze authentic Os Draconis,fossilized Os Draconis,counterfeit products,and lab-prepared modern animal bones.The analytical techniques included ^(14)C dating,electron probe microanalysis(EPMA),polarized light microscopy,X-ray diffraction(XRD),inductively coupled plasma mass spectrometry(ICP-MS),and fourier-transform infrared spectroscopy(FTIR).The study focused on examining the microstructural features and micro-area elemental compositions to identify distinguishing characteristics.Results:Physical identification alone was insufficient to reliably distinguish authentic Os Draconis from its counterfeits.XRD analysis revealed that while hydroxyapatite is the main component in all samples,authentic Os Draconis also contains calcium carbonate and quartz,which were absent in counterfeit and lab-prepared samples.FTIR spectra identified the carbonate ion(CO_(3)^(2-))as a characteristic infrared marker for authentic Os Draconis.ICP-MS analysis showed that Ca and P are the major elements,with a notably high content of Lanthanum(La)among rare earth elements in authentic samples.The EPMA results demonstrated that the Ca/P ratio of authentic Os Draconis is distinct,falling between that of fossilized Os Draconis and counterfeit samples.Conclusion:This study successfully identified several precise markers,including the presence of calcium carbonate,the characteristic CO_(3)^(2-)infrared peak,a high La content,and a specific Ca/P ratio,for the accurate and rapid authentication of Os Draconis.Furthermore,the analysis of its natural porous structure,suitable pore size,and surface area suggests that Os Draconis has significant potential as a natural drug carrier. 展开更多
关键词 Os Draconis ULTRASTRUCTURE ^(14)C dating EPMA XRD ICP-MS FTIR
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A Multi-Stage Pipeline for Date Fruit Processing: Integrating YOLOv11 Detection, Classification, and Automated Counting
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作者 Ali S.Alzaharani Abid Iqbal 《Computers, Materials & Continua》 2026年第1期1327-1353,共27页
In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in... In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in real time by drawing bounding boxes around them.These bounding boxes are subsequently passed to a YOLOv11 classification model,which analyzes cropped images and assigns class labels.An additional counting module automatically tallies the detected fruits,offering a near-instantaneous estimation of quantity.The experimental results suggest high precision and recall for detection,high classification accuracy(across 15 classes),and near-perfect counting in real time.This paper presents a multi-stage pipeline for date fruit detection,classification,and automated counting,employing YOLOv11-based models to achieve high accuracy while maintaining real-time throughput.The results demonstrated that the detection precision exceeded 90%,the classification accuracy approached 92%,and the counting module correlated closely with the manual tallies.These findings confirm the potential of reducing manual labour and enhancing operational efficiency in post-harvesting processes.Future studies will include dataset expansion,user-centric interfaces,and integration with harvesting robotics. 展开更多
关键词 Date fruit cultivation YOLOv11 precision agriculture real-time processing automated fruit counting deep learning agricultural productivity
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Neuroprotection by resveratrol-glucuronide and quercetin-glucuronide via binding to polyphenol-and glycosaminoglycan-binding sites in the laminin receptor 被引量:1
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作者 Rayudu Gopalakrishna Jennifer Aguilar +1 位作者 Emily Lee William J.Mack 《Neural Regeneration Research》 SCIE CAS 2025年第3期819-820,共2页
The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated ... The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated forms, and not as the aglycone parent form(Pasinetti et al.,2015). 展开更多
关键词 RESVERATROL MOLAR dated
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Decoding complexity: the need to enhance precision and streamline spatial understanding in neuroscience
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作者 Sameehan Mahajani Armita Salahi +2 位作者 Brenda Gonzalez Charlotte Nelson Frank Hsiung 《Neural Regeneration Research》 SCIE CAS 2025年第3期801-802,共2页
Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides i... Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides in elucidating the intricate correlation between structural information and the functioning of the human brain. 展开更多
关键词 behavior FRONTIER DATING
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Instructions for Authors of Chemical Research in Chinese Universities
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《高等学校化学学报》 北大核心 2025年第4期F0003-F0003,共1页
The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and rev... The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and reviews written by faculty members,researchers and postgraduates in universities,colleges and research institutes all over China and overseas.It reports the latest and the most creative results of important fundamental research in all aspects of chemistry and of developments with significant consequences across sub-disciplines.This journal is sponsored by Jilin University and mandated by the Ministry of Education of P.R.China. 展开更多
关键词 JOURNAL consequences dated
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How to Understand in-situ U-Pb Isotopic Data of Uraninite and Pitchblende?
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作者 Chunying Guo 《Journal of Earth Science》 2025年第4期1835-1841,共7页
0 INTRODUCTION Uraninite and pitchblende are the most important ore minerals in nearly all types of uranium deposits.Therefore,the U-Pb isotopic system of uraninite and pitchblende are widely used in dating uranium de... 0 INTRODUCTION Uraninite and pitchblende are the most important ore minerals in nearly all types of uranium deposits.Therefore,the U-Pb isotopic system of uraninite and pitchblende are widely used in dating uranium deposits. 展开更多
关键词 URANINITE DATING dating uranium deposits situ u pb isotopic data PITCHBLENDE ore minerals uranium deposits
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First discovery of the Late Triassic syenite and coeval epigenetic Cu mineralization in the Jianglang Dome, eastern Tibetan Plateau, China
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作者 Yanpei Dai Yudi Zhu +4 位作者 Di Xiu Huihua Zhang Shengxian Liang Tongzhu Li Qing Zhou 《Acta Geochimica》 2025年第3期478-495,共18页
The Jianglang Dome has integral tectonostratigraphic units and contains a suite of high-grade stratiform Cu deposits.However,the formation mechanism of this dome and genetic model of Cu mineralization remain a matter ... The Jianglang Dome has integral tectonostratigraphic units and contains a suite of high-grade stratiform Cu deposits.However,the formation mechanism of this dome and genetic model of Cu mineralization remain a matter of debate.The resolution of these problems hinges on the presence of magmatic intrusions in the core.Here,we report bulk geochemical and zircon U-Pb data of a newly discovered syenite intrusion as well as chalcopyrite Re-Os dating results.We aim to explore genesis of the Jianglang Dome,genetic model of the stratiform Cu deposits,and rare metal mineralization potential of the syenite intrusion.The dated syenite sample yields an emplacement age of 207.1±2.0 Ma,which matches post-collisional extension in the Songpan-Ganze Orogen.The syenite rocks have average high(Zr+Nb+Ce+Y)concentrations of 512 ppm,10000.Ga/Al ratios of 3.97,and crystallization temperatures of 827°C,together with low Mg#values of 1.73;they fi t the A-type granitoid defi nition and a crustal origin.Chalcopyrite separates yield a Re-Os isochron age of 207.1±5.3 Ma,which markedly postdates the formation age of their orehosting rocks(the Liwu Group,ca.553 Ma).Our new age determination,together with previous chalcopyrite Re–Os isochron age of ca.151.1 Ma and sulfi de sulfur isotope(δ^(34)S_(V-CDT)=8.7‰–5.6‰)and tourmaline boron isotope(δ^(11)B=−15.47‰to−5.91‰)data,confi rms multistage epigenetic Cu mineralization related to magmatic-hydrothermal fl uids.Compared with regional ca.209–207 Ma fertile granitoids,the studied syenite intrusion shows unevolved and barren affi nities and negligible rare metal mineralization potential.Combined with residual gravity low anomalies in the core of the Jianglang Dome,which suggest a large deepseated granitic batholith,we prefer thermal doming resulting from magma-induced uplift for the nature of this dome. 展开更多
关键词 Syenite intrusion Zircon U-Pb dating Chalcopyrite Re-Os dating Epigenetic mineralization Stratiform Cu deposits Jianglang Dome
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First discovery of Cretaceous tuffs in the Zhenyuan area,southwestern Ordos Basin,China:Constraints from zircon U-Pb dating
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作者 Yin Chen Lu-lu Chen +1 位作者 Jian-guo Li Hua-lei Zhao 《China Geology》 2025年第2期457-459,I0048,I0053,共5页
1.Objective,The Cretaceous succession is characteristic of the aeolian sedimentary system in the Ordos Basin,which is the major ore-bearing layer for the sandstone-type uranium deposits.Based on the research of paleon... 1.Objective,The Cretaceous succession is characteristic of the aeolian sedimentary system in the Ordos Basin,which is the major ore-bearing layer for the sandstone-type uranium deposits.Based on the research of paleontology and magnetostratigraphy,formers believed it belonged to the Early Cretaceous(Huang YB,2010).However,the lack of intrusions or volcanic rocks for isotopic dating results in an unclear formation age for the Lower Cretaceous succession.Recently,tuffs were firstly discovered in the Luohandong Formation in the Zhenyuan area,Gansu Province,located in the southwestern Ordos Basin,China.The LA-ICP-MS zircon U-Pb dating of tuffs was carried out.The new ages can precisely constrain the depositional age of the Luohandong Formation and also provide significant indications for the study of regional volcanic activities,paleoclimate,basin evolution,and tectonic setting. 展开更多
关键词 southwestern ordos basin cretaceous tuffs cretaceous succession volcanic rocks aeolian sedimentary system la icp ms zircon u pb dating isotopic dating depositional age
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Updating the Outdated
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作者 QI YU 《China Today》 2025年第3期74-75,共2页
The ideology of being ready to make innovation and keeping abreast of the times is a defining feature of the Chinese civilization.IN several of his recent speeches President Xi Jinping stressed that the Chinese civili... The ideology of being ready to make innovation and keeping abreast of the times is a defining feature of the Chinese civilization.IN several of his recent speeches President Xi Jinping stressed that the Chinese civilization has the tradition of discarding the outdated in favor of the new and moving ahead with the times.In exploring a new philosophy that is suitable for governing China in the new era,China draws on its fine traditional culture to find ways of abolishing outdated ideas and making theoretical,practical,and institutional innovations,thus staying abreast of the time to create a better future. 展开更多
关键词 dated DATING CULTURE
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Tracing carbonate diagenesis and hydrothermal activity during the opening of the Central South Atlantic: Insights from the Santos Basin (Brazil)
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作者 Igor Figueiredo Cristiano Lana +5 位作者 Fernando F.Alkmim Marco A.Silva Maria Eugênia S.Souza Dorval C.Dias-Filho Eveline E.Zambonato Katia R.N.Mendonça 《Geoscience Frontiers》 2025年第5期245-259,共15页
The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick s... The opening of the Central South Atlantic and the consequent formation of the eastern Brazilian continental margin was marked by a complex history of mafic magmatism,carbonate sedimentation,and deposition of a thick salt layer.The carbonates underlying the salt layer(pre-salt carbonates)were formed in restricted lacustrine basins.Here,the timing and fluid sources of deposition,diagenetic,and hydrothermal alterations of the pre-salt carbonate rocks are defined through in-situ U-Pb dating,87Sr/86Sr,and trace element analyses of samples from the Santos Basin.The very alkaline nature of the Aptian lake(s)produced characteristically unique and widely distributed carbonate rocks such as Mg-clays with calcite spherulite and calcite crystal shrub limestones transitioning laterally and vertically into travertines formed by hydrothermal pulses during basin evolution.Hydrothermalism caused extensive replacement,dissolution,and calcite cementation.REE+Y PAAS-normalised patterns and 87Sr/86Sr ratios indicate that deposition/eo-diagenesis of the primary carbonates occurred in a lacustrine environment primarily controlled by evaporation,pH,and continental water source,with 2%–10%hydrothermal fluid input.Trace elements and Sr-isotope of travertines and burial diagenetic phases show that they are produced from a hot mixture of mafic/mantle-derived fluids and dissolution/alteration of older carbonate formations.U-Pb dating indicates that carbonate deposition occurred between 124.8±2.6 Ma and 120.0±1.6 Ma,earlier than previously proposed,followed closely by the circulation of hydrothermal fluids.Replacement and cementation ages range from 120.5±2.4 Ma to 80.4±2.4 Ma. 展开更多
关键词 PRE-SALT CARBONATE U-Pb dating Sr-isotope Trace elements LA-ICP-MS
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Evolutionary history of Old World cellar spiders in the context of Neo-Tethyan sea-land transformations
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作者 Zhi-Yuan Yao Shu-Qiang Li 《Zoological Research》 2025年第4期912-920,共9页
The ancient Neo-Tethyan region underwent profound tectonic transformations,including the orogenesis of the Xizang Plateau and the westward retreat and ultimate closure of the Neo-Tethyan Ocean.These events significant... The ancient Neo-Tethyan region underwent profound tectonic transformations,including the orogenesis of the Xizang Plateau and the westward retreat and ultimate closure of the Neo-Tethyan Ocean.These events significantly influenced the diversification and biogeography of aquatic animals.However,the impact of these large-scale sea-land shifts on the long-range evolutionary history of terrestrial fauna remains unclear.This study investigated how geological changes in the Neo-Tethyan region shaped the evolutionary trajectories and dispersal patterns of Pholcus sensu lato cellar spiders across the Old World.Molecular dating,ancestral area reconstructions,and diversity analyses were conducted using sequences from seven genes across 234 samples representing 209 species.Results indicated that these spiders originated in the eastern Neo-Tethyan region during the Early Eocene,with their subsequent diversification driven by a series of concomitant geological events.The Eurasian(ER)Group dispersed into Europe following the westward retreat of the Neo-Tethyan Ocean in the Early Miocene,while the African(AF)Group migrated into Africa via the Arabian Plate land bridge following the closure of the Neo-Tethyan Ocean in the Oligocene.The East Asian(EA)Group,which expanded along the southeastern margin of the Himalayas,experienced explosive diversification in response to sustained orogenesis at the Eocene-Oligocene boundary.These findings illustrate how large-scale geological processes and sea-land changes shaped the evolutionary history of terrestrial fauna in the Neo-Tethyan region. 展开更多
关键词 BIOGEOGRAPHY DIVERSIFICATION Distribution pattern Molecular dating PHOLCIDAE
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OsELF3.1-OsCATA-Ghd7 Pathway Regulates Rice Heading
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作者 WU Zhaozhong ZHONG Zhengzheng +13 位作者 XU Peng LIU Ling WANG Beifang YANG Qinqin WEN Xiaoxia MA Guifang LUO Mili ZHANG Yingxin LIU Qun’en PENG Zequn ZHAN Xiaodeng CAO Liyong CHENG Shihua WU Weixun 《Rice science》 2025年第5期658-672,I0072-I0078,共22页
Rice,a critical global staple crop,relies heavily on heading date,a key agronomic trait marking the transition from vegetative to reproductive growth.Understanding the genetic regulation of heading date is vital for e... Rice,a critical global staple crop,relies heavily on heading date,a key agronomic trait marking the transition from vegetative to reproductive growth.Understanding the genetic regulation of heading date is vital for enhancing the adaptability of high-quality rice varieties across diverse geographical regions and for bolstering local food security.In this study,we uncovered a novel role for OsCATA,a catalase gene,in the regulation of photoperiodic flowering in rice.We identified a novel allele of OsELF3.1,whose mutation resulted in delayed heading.Further analyses revealed that OsELF3.1 physically interacted with OsCATA.Notably,OsCATA exhibited rhythmic expression patterns similar to OsELF3.1 and,when mutated,also delayed flowering.Expression analyses showed that the delayed heading phenotype could be attributed to elevated Ghd7 expression under both long-day and short-day conditions,with OsCATA expression positively regulated by OsELF3.1.Double mutants of OsELF3.1 and OsCATA displayed a heading delay similar to that of oself3.1 single mutants.Additionally,OsELF3.1 could interact with Ghd7 in vivo,alleviating its suppression of Ehd1.Luciferase assays confirmed that Ghd7 repressed Ehd1 expression,while OsELF3.1 mitigated this repression.Collectively,our findings reveal that OsCATA is critical in suppressing Ghd7 expression through the OsELF3.1-OsCATA-Ghd7 transcriptional pathway,thereby regulating rice heading. 展开更多
关键词 RICE heading date OsELF3.1 Ghd7 OsCATA
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Discovery of an ancient Himalayan birch mouse lineage illuminates the evolution of the family Sicistidae(Rodentia:Dipodoidea),with descriptions of a new genus and two new species
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作者 Zhong-Xu Zhu Quan Li +12 位作者 Wen-Yu Song Xue-You Li Andrey Lissovsky Mu-Yang Wang Xiao-Xin Pei Kang Luo Jing Luo Ming-Jin Pu Chang-Zhe Pu Hong-Jiao Wang Zhu Liu Zhong-Zheng Chen Xue-Long Jiang 《Zoological Research》 2025年第4期921-938,共18页
Birch mice(family Sicistidae)are small dipodoid rodents distributed in regions surrounding the Qinghai-Xizang Plateau and extending across the Palearctic.In China,members of the genus Sicista are rarely recorded,and t... Birch mice(family Sicistidae)are small dipodoid rodents distributed in regions surrounding the Qinghai-Xizang Plateau and extending across the Palearctic.In China,members of the genus Sicista are rarely recorded,and their systematics remain poorly resolved.As part of the Second Xizang Plateau Expedition by the Kunming Institute of Zoology,Chinese Academy of Sciences,systematic surveys conducted in southern Xizang and the western Tianshan Mountains yielded two previously unrecognized species.Two specimens from southern Xizang were found to occupy a deeply divergent phylogenetic position within Sicistidae.Morphological assessments and molecular phylogenetic analyses of both extant and fossil Sicistidae,along with total-evidence dating and ancestral distribution reconstruction,identified these specimens as representatives of an ancient extant lineage that diverged from Sicista approximately 20.38 million years ago.This lineage is designated as a new genus,defined by the new species Breviforamen shannanensis gen.et sp.nov.Furthermore,11 specimens from the Tianshan Mountains are described as a second new species,Sicista brevicauda sp.nov.,based on diagnostic morphological and genetic features.Ancestral distribution reconstructions,combined with fossil records,indicate an early Miocene origin for Sicistidae across a broad region spanning the“Gobi”Desert to parts of North America.Climatic deterioration and increasing desertification during the mid-Miocene likely drove southward dispersal of Breviforamen gen.nov.into southern Xizang prior to the complete formation of the Yarlung Zangbo River.Overall,these findings broaden current understanding of Sicistidae diversity,elucidate the origin and dispersal patterns of the family,and highlight the presence of an ancient relict lineage in China. 展开更多
关键词 Breviforamen shannanensis BIOGEOGRAPHY Phylogeny Sicista brevicauda Total evidence dating Xizang Xinjiang
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Detrital Zircon U-Pb Dating and Hf Isotopes of the Crocker Fan Sandstones in Sabah,North Borneo:Constraints on Their Provenance and the Tectonic Evolution of Borneo
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作者 Aimei Zhang Liyan Ma +6 位作者 Haidong Li Junaidi Asis Xudong Fang Qi Fang Min Chen Min Ren Xiaoying Dong 《Journal of Earth Science》 2025年第3期894-909,共16页
The tectonic evolution of Borneo and the affiliation between Southern and Northern Borneo remains unclear.The Rajang and Crocker Fan sediments,as one of the largest ancient submarine fans in Southeast Asia have witnes... The tectonic evolution of Borneo and the affiliation between Southern and Northern Borneo remains unclear.The Rajang and Crocker Fan sediments,as one of the largest ancient submarine fans in Southeast Asia have witnessed the tectonic evolution of Borneo since at least the late Mesozoic.In this study,we present laser ablation inductively coupled plasma mass spectrometer(LA-ICP-MS)U-Pb dating and Hf isotopic results of detrital zircons from the Trusmadi and Crocker formations within the Crocker Fan of Sabah,Northern Borneo.Our results,coupled with previous data,show that the Crocker Fan sediments in Sabah of Northern Borneo display similar age spectra to the Rajang Fan sediments in Sarawak of Central Borneo,with two major age clusters at 130-80 and 280-200 Ma.Further provenance analysis based on mineral shape with a prismatic characteristic and similar detrital zircon Hf isotopes of the two formations illustrates that the Jurassic-Cretaceous and partly Triassic detrital zircons of the Crocker and Rajang Fan sediments were derived from the erosion of contemporaneous magmatic rocks;part of Permian-Triassic ones could be the recycling of the Jurassic deposits in SW Borneo.The initial provenance of these Permian-Triassic detritus could be synchronous magmatic rocks in the Tin belt of the Malay Peninsula.Combining with previous data,we propose that the entire Borneo continent,including both Southern and Northern Borneo,developed a common Mesozoic continental magmatic arc.Moreover,we postulate that the Rajang and Crocker fans formed in a fore-arc extensional rift basin related to the retreat of the subducted Paleo-Pacific Plate beneath the Northern Borneo margin. 展开更多
关键词 detrital zircon U-Pb dating Hf isotope Crocker Fan SABAH Paleo-Pacific geochemistry tectonics
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Geochemistry and U–Pb dating of diorite rocks in Xiaoqinggou mining area,Jilin Province
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作者 WANG Yuxiang SUN Fengyue +3 位作者 WANG Li HUI Chao WANG Zhengsong DOU Desheng 《Global Geology》 2025年第4期217-230,共14页
To investigate the Early Cretaceous magmatic activity and tectonic evolution in the Xiaoqinggou mining area of Jilin Province,the authors conducted petrological,geochemical,and isotopic analyses of diorite rocks.The f... To investigate the Early Cretaceous magmatic activity and tectonic evolution in the Xiaoqinggou mining area of Jilin Province,the authors conducted petrological,geochemical,and isotopic analyses of diorite rocks.The findings show that the zircons exhibit distinct magmatic growth zoning,confirming their magmatic origin.LA–ICP–MS zircon U–Pb dating yielded an age of 128.7±2.2 Ma,corresponding to Early Cretaceous.Geochemical data reveal that the diorite rocks are high and potassium but low in sodium,classifying them within the peraluminous,high-potassium calc-alkaline series.They are enriched in large ion lithophile elements(e.g.,K,Ba and Rb)and depleted in high field strength elements(e.g.,Nb,Ta and Ti).TheδEu values range from 1.07 to 1.14,indicating weakly positive Eu anomalies.Regional comparisons and integrated studies suggest that the Xiaoqinggou diorite rocks formed in a volcanic island arc setting,associated with the westward subduction of the Paleo-Pacific plate beneath the Eurasian continent in an extensional tectonic environment.This study provides a theoretical basis for further exploration of the Xiaoqinggou deposit. 展开更多
关键词 DIORITE zircon U-Pb dating GEOCHEMISTRY Early Cretaceous Xiaoqinggou deposit
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First SHRIMP Zircon U-Pb Dating Constraints for the Ediacaran Wenghui Biota
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作者 Mingsheng Zhao Feng Tang +4 位作者 Giovanni Mussini Yulan Li Heng Zhang Jianshu Chen Linzhi Gao 《Journal of Earth Science》 2025年第1期102-112,共11页
The Ediacaran Period records a significant turning point in the evolution of life on Earth,witnessing the rise to ecological dominance of macroscopic tissue-grade organisms.The Wenghui biota from the Doushantuo Format... The Ediacaran Period records a significant turning point in the evolution of life on Earth,witnessing the rise to ecological dominance of macroscopic tissue-grade organisms.The Wenghui biota from the Doushantuo Formation of South China hosts abundant multicellular algal macrofossils and problematica,some of which might be closely related to taxa from classic Late Ediacaran assemblages from South Australia and the White Sea biota of Russia.However,a lack of well-resolved isotopic age estimates has hampered efforts to constrain the timing of appearance of the Wenghui biota,obfuscating its significance to our understanding of Ediacaran macroevolution in the aftermath of the Snowball Earth events.Here,we present the first SHRIMP zircon U-Pb dating results for samples obtained from a laminated tuff ash layer at the base of the Wenghui biota in the Doushantuo Formation,Jiangkou County,Tongren City,Guizhou Province,China.Our analyses yield an age of 595.4±5.3 Ma for the first appearance of Wenghui biota,suggesting that its appearance postdated that of the Lantian and Weng'an biotas,but preceded that of the Miaohe biota.These newly obtained age proxies offer an independent test of previous isotopic estimates for the age of the Wenghui biota,providing new chronostratigraphic evidence to map the succession of Ediacaran fossil assemblages on the Yangtze Platform during the Doushantuo interval.These data suggest that the Lantian,Weng'an,Wenghui,and Miaohe biotas may record a sequence of biotic assemblages attesting to successive phases in the radiation of Ediacaran macroscopic organisms,particularly macroalgae. 展开更多
关键词 ZIRCON SHRIMP U-Pb dating Wenghui biota Doushantuo Formation Ediacaran system southern China
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Ghd7.1 improves eating quality by reducing grain protein content in rice
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作者 Kaijing Yuan Yage Dong +3 位作者 Wenqiang Sun Liting Zhang Muhammad Asif Sibin Yu 《The Crop Journal》 2025年第4期1145-1155,共11页
Protein content plays a crucial role in determining the eating and cooking quality of rice.However,the genetic and molecular basis underlying grain protein content remains to be elucidated.In this study,we identified ... Protein content plays a crucial role in determining the eating and cooking quality of rice.However,the genetic and molecular basis underlying grain protein content remains to be elucidated.In this study,we identified a genomic region associated with grain protein content in rice chromosome segment substitution lines containing the flowering gene Ghd7.1,which reduced grain protein content by repressing the transcription of the gene OsAAP6.Knockout of Ghd7.1 increased grain protein content and decreased the eating and cooking quality of rice.Introduction of the functional haplotype of Ghd7.1 into two elite rice cultivars reduced their protein content and increased their eating quality and grain yield with no effect on the regulation of flowering time.Ghd7.1 might be used for regulating the protein content and improving the eating quality of rice varieties. 展开更多
关键词 Protein content Rice grain PALATABILITY Heading date
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Zircon U-Pb dating of the Shazibu Pluton in the Guocheng gold belt, Jiaolai Basin, Shandong Province: Implications for metallogeny of the Jiaodong gold province
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作者 Yuan-yuan Feng Ya-dong Li +2 位作者 An-kai Geng Liu-an Duan Da-dou Li 《China Geology》 2025年第1期230-232,共3页
1.Objective Three stages of Mesozoic magmatic activity have been identified in the Jiaodong area,namely early magmatic emplacement,the magmatic emplacement prior to mineralization,and magmatic activity post-mineraliza... 1.Objective Three stages of Mesozoic magmatic activity have been identified in the Jiaodong area,namely early magmatic emplacement,the magmatic emplacement prior to mineralization,and magmatic activity post-mineralization,from early to late. 展开更多
关键词 DATING BELT MINERALIZATION
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“Now You See Me”:A Neural Pathway Independent of the Amygdala Responsible for Fear and Anxiety
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作者 Xiaojie Zhang Cenglin Xu Zhong Chen 《Neuroscience Bulletin》 2025年第1期186-188,共3页
Fear,as a type of psychological state and negative emotion,represents a common reflex towards the presence or imminence of danger.Clinically,fear-related disorders such as panic disorder and anxiety disorder can lead ... Fear,as a type of psychological state and negative emotion,represents a common reflex towards the presence or imminence of danger.Clinically,fear-related disorders such as panic disorder and anxiety disorder can lead to impaired psychological and physiological conditions.Elucidating the neural basis of fear is of particular importance in developing targeted therapies.It is currently well-established that the amygdala plays a pivotal role in mediating various expressions of fear[1].However,silencing or inhibiting the amygdala only partially reduces fear-related behaviors[2],leading scientists to guess whether there exists an amygdalaindependent alternative neural pathway that conveys fear.Excitingly,a very recent elegant study published in Nature Neuroscience by Wang et al.from Zhejiang University has addressed this question.They present a tetra-synaptic forebrain-to-hindbrain pathway that is responsible for odordriven innate fear and anxiety(Fig.1)[3]. 展开更多
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