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Integrative biogeography: Validating hypotheses of species distribution 被引量:1
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作者 Zhong-E Hou Shu-Qiang Li 《Zoological Research(Diversity and Conservation)》 2024年第1期86-88,共3页
DEAR EDITOR,Biogeography is a scientific field dedicated to the investigation of the origins and distribution patterns of organisms,as well as predicting future alterations in their geographical distributions(Cox&... DEAR EDITOR,Biogeography is a scientific field dedicated to the investigation of the origins and distribution patterns of organisms,as well as predicting future alterations in their geographical distributions(Cox&Moore,2005).However,the majority of conclusions drawn within the field of biogeography are hypothetical.Rigorous testing of these biogeographic hypotheses remains a considerable challenge.This paper presents the concept of“integrative biogeography”,which emphasizes the experimental testing of biogeographic hypotheses through studies on geological history,as well as biotic and abiotic factors(Figure 1). 展开更多
关键词 BIOGEOGRAPHY DISTRIBUTION dating
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U-Pb dating of monazite in the Bainiuchang silver polymetallic deposit,Yunnan Province,and its limitation on Mesozoic mineralization
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作者 Bo-de Lu Wen-chang Li +10 位作者 Xue-long Liu Guang-zhi Meng Qi-he Long Hong Zhang Jun-shan Dao Fang-lan Li Jie-hu Zhou Mao-huang Fan Xue Mi Nan Shi Zhen-liang Cao 《China Geology》 CAS CSCD 2024年第3期592-595,共4页
1.Objective The Gejiu-Bozhushan-Laojunshan tin-tungsten polymetallic metallogenic belt is located in southeastern Yunnan.It is bounded by the Mile-Shizong Fault and the Yangzi Plate to the north and west,respectively,... 1.Objective The Gejiu-Bozhushan-Laojunshan tin-tungsten polymetallic metallogenic belt is located in southeastern Yunnan.It is bounded by the Mile-Shizong Fault and the Yangzi Plate to the north and west,respectively,while the Honghe Fault represents its southwestern boundary.It is adjacent to the Ailaoshan Fault,and extends to Guangxi and Vietnam to the southeast(Fig.1a;Liu JP et al.,2021). 展开更多
关键词 silver dating SOUTHEAST
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Muscovite^(40)Ar/^(39)Ar isotopic dating of pegmatite veins in the Bieyesamas rare metal deposit in the Altay Mountain,Xinjiang,northwestern China
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作者 Geng-biao Qiao Ping Wang +1 位作者 Xiao-hong Wang Jun-lu Chen 《China Geology》 CAS CSCD 2024年第3期589-591,共3页
1.Objective The Altay Orogenic Belt in Xinjiang,China is located in the west of the Central Asian Orogenic Belt and in the transition zone between the Siberian Plate and the Kazakhstan-Junggar Plate,extending approxim... 1.Objective The Altay Orogenic Belt in Xinjiang,China is located in the west of the Central Asian Orogenic Belt and in the transition zone between the Siberian Plate and the Kazakhstan-Junggar Plate,extending approximately 500 km in northern Xinjiang,China(Fig.1a).The Altay Orogenic Belt has undergone two-way accretion of the Paleozoic crust and the Meso-Cenozoic intracontinental orogeny,leading to the formation of large numbers of intermediate-acid intrusions.More than 100000 pegmatite veins have been discovered in the intermediate-acid intrusions,and they constitute an important rare metal metallogenic belt of China(Fig.1b). 展开更多
关键词 XINJIANG dating isotopic
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Cassiterite U-Pb dating of the Yelonggou pegmatite-type lithium deposit in western Sichuan and its metallogenic age constraints
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作者 Xiang-yuan Yue Qian Zhang +4 位作者 Jun-jun Zhang Wei Zhang Jing Zhang Zhi-quan Jia Li-ping Luo 《China Geology》 CAS CSCD 2024年第1期153-156,共4页
1.Objective Pegmatite hosts important resource of rare metals,e.g.,lithium(Li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type depo... 1.Objective Pegmatite hosts important resource of rare metals,e.g.,lithium(Li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type deposits,for which accurate dating of pegmatite formation and mineralization is essential.The Songpan-Ganzi orogenic belt is a major rare metal metallogenic belt in China,hosting many important pegmatite-type Li deposits,including the Lijiagou,Dangba,Jiajika,Yelonggou,Cuola,and Declalongba.Radiometric age data(mica Ar-Ar and zircon/cassiterite U-Pb)from these Li deposits are sparse,ranging from 210 to 152 Ma.However,obtaining reliable zircon U-Pb dates can be a challenge due to the strong decidualization in pegmatites.As a result,the formation and mineralization ages of these rare metal pegmatites remain controversial,which hampers the development of pegmatite-type metallogenic model for the Songpan-Ganzi orogenic belt. 展开更多
关键词 dating METALLOGENIC ZIRCON
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Mineral Chemistry,Trace Elements,Isotopic Analysis and Zircon U-Pb Dating in the Hesar Pluton,Northern UDMA,Iran:Implications for Pre-Collisional Magma Mixing
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作者 Kazem KAZEMI Soroush MODABBERI +3 位作者 Parisa GHARIBNEJAD XIAO Yilin Fatemeh SARJOUGHIAN Ali KANANIAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期657-678,共22页
The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were measured.It is suggested th... The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were measured.It is suggested that the rocks are metaluminous(A/CNK=1.32-1.45),subduction-related I-type calc-alkaline gabbro to diorite with similar mineral assemblages and geochemical signatures.The host rocks yielded an U-Pb crystallization age of 37.3±0.4 Ma for gabbro-diorite.MMEs have relatively low SiO_(2) contents(52.9-56.6 wt%)and high Mg^(#)(49.8-58.7),probably reflecting a mantle-derived origin.Chondrite-and mantle-normalized trace element patterns are characterized by LREE and LILE enrichment,HREE and HFSE depletion with slight negative Eu anomalies(Eu/Eu^(*)=0.86-1.03).The host rocks yield(^(87)Sr/^(86)Sr)_(i) ratios of 0.70492-0.70510,positive ε_(Nd)(t)values of+1.55-+2.06 and T_(DM2)of 707-736 Ma,which is consistent with the associated mafic microgranular enclaves((^(87)Sr/^(86)Sr)_(i)=0.705014,ε_(Nd)(t)=+1.75,T_(DM2)=729 Ma).All data suggest magma-mixing for enclave and host rock formation,showing a complete equilibration between mixed-mafic and felsic magmas,followed by rapid diffusion.The T_(DM1)(Nd)and T_(DM2)(Nd)model ages and U-Pb dating indicate that the host pluton was produced by partial melting of the lower continental crust and subsequent mixing with injected lithospheric mantlederived magmas in a pre-collisional setting of Arabian-Eurasian plates.Clinopyroxene composition indicates a crystallization temperature of~1000℃ and a depth of~9 km. 展开更多
关键词 ENCLAVE magma mixing zircon U-Pb dating Urumieh-Dokhtar magmatic arc
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Effect of dates on blood glucose and lipid profile among patients with type 2 diabetes
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作者 Hyder Osman Mirghani 《World Journal of Diabetes》 SCIE 2024年第6期1079-1085,共7页
Poor fruit and vegetable consumption is one of the 10 major risk factors for mortality.There is a misconception regarding the consumption of dates among patients with diabetes.This manuscript assessed the effects of d... Poor fruit and vegetable consumption is one of the 10 major risk factors for mortality.There is a misconception regarding the consumption of dates among patients with diabetes.This manuscript assessed the effects of date consumption on fasting and postprandial blood glucose,glycated hemoglobin,total cholesterol,triglycerides,low-density lipoproteins,high-density lipoproteins,and microbial markers.Four literature databases were searched for relevant articles.Of the 595 studies retrieved,24 assessed the effects of dates on glycemic control and lipids.Overall,the evidence suggests that dates have a lowering effect on blood glucose.Dates reduce total cholesterol and triglyceride levels and increase high-density lipoprotein levels.Dates also promote the abundance of beneficial gut microbiota.Therefore,patients with diabetes and dyslipidemia can consume dates to reduce their blood glucose,cholesterol,and triglycerides. 展开更多
关键词 DATES Lipid profile Blood glucose Diabetes mellitus Microbial contamination
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Effects of Seeding Date and Density on Yield and Agronomic Traits of Millet : A Case Study of Wangu 098 Variety of Millet
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作者 Yinting NIU Le JU +3 位作者 Peiyu CHEN Zhigang YIN Xuejie QIANG Junxia LI 《Asian Agricultural Research》 2024年第4期33-36,共4页
[Objectives]To find out a suitable cultivation technique of Wangu 098 in Nanyang area,speed up the popularization,demonstration and application of Wangu 098,and provide a theoretical and practical basis for adjusting ... [Objectives]To find out a suitable cultivation technique of Wangu 098 in Nanyang area,speed up the popularization,demonstration and application of Wangu 098,and provide a theoretical and practical basis for adjusting the planting structure and realizing the matching of improved varieties and methods.[Methods]The new self-bred millet variety Wangu 098 was used as the material,and the two-factor split zone experimental design was adopted.The effects of different sowing dates and densities on the yield,growth period and agronomic characters of millet were studied.[Results]The interaction of seeding date and density had a great effect on the yield and plant traits of millet.Millet yield was significantly and positively correlated with plant height,panicle length,single panicle weight,panicle grain weight and tiller number.[Conclusions]The reasonable combination of seeding date and density could give full play to the yield potential of millet.According to the experimental results and cultivation experience,the suitable seeding date of millet in Nanyang area is in the first and middle ten days of June,and the best density is about 750000 plants/ha.However,after June 30,the seeding millet did not tiller,so the density should be increased to more than 900000 plants/ha to obtain higher yield.In terms of cultivation and management,timely seeding,reasonable close planting,and coordination of vegetative growth and reproductive growth can make the plant tall and strong,panicle long and thick,and improve the yield of millet. 展开更多
关键词 Wangu 098 MILLET SEEDING date DENSITY AGRONOMIC traits YIELD
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Inferring Eupolypods Divergence Time Using Bayesian Tip-Dating
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作者 Yiran Wang Chunxiang Li 《Open Journal of Geology》 CAS 2024年第2期247-258,共12页
According to the most recent Pteridophyte Phylogeny Group (PPG), eupolypods, or eupolypod ferns, are the most differentiated and diversified of all major lineages of ferns, accounting for more than half of extant fern... According to the most recent Pteridophyte Phylogeny Group (PPG), eupolypods, or eupolypod ferns, are the most differentiated and diversified of all major lineages of ferns, accounting for more than half of extant fern diversity. However, the evolutionary history of eupolypods remains incompletely understood, and conflicting ideas and scenarios exist in the literature about many aspects of this history. Due to a scarce fossil record, the diversification time of eupolypods mainly inferred from molecular dating approaches. Currently, there are two molecular dating results: the diversification of eupolypods occurred either in the Late Cretaceous or as early as in the Jurassic. This study uses the Bayesian tip-dating approach for the first time to infer the diversification time for eupolypods. Our analyses support the Jurassic diversification for eupolypods. The age estimations for the diversifications of the whole clade and one of its two subclades (the eupolypods II) are both in the Jurassic, which adds to the growing body of data on a much earlier diversification of Polypodiales in the Mesozoic than previously suspected. 展开更多
关键词 Eupolypods MID-CRETACEOUS FOSSILS Bayesian Tip-dating
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以学生为中心的BOPPPS教学模型+DATE监控模式在药理学教学中的应用探索
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作者 赵丽琼 《中国科技经济新闻数据库 教育》 2024年第8期0182-0185,共4页
随着教育改革的推广和深入,当前教学的模式开始逐渐的丰富化和多元化,各个教学理念、教学模型层出不穷,在这样的背景下,结合学科的特质和需求,设计良好的教学模式,认知理论和构建主义是BOPPPS教学模型的理论和依据,该模型是一个能够帮... 随着教育改革的推广和深入,当前教学的模式开始逐渐的丰富化和多元化,各个教学理念、教学模型层出不穷,在这样的背景下,结合学科的特质和需求,设计良好的教学模式,认知理论和构建主义是BOPPPS教学模型的理论和依据,该模型是一个能够帮助教师分解并分析教学过程、找出教学盲点、改善并提升教学成效的工具。如何使学生在课堂上最大限度的掌握知识,是其关注的重点,教学互动和反馈是其突出的特点。BOPPPS教学模型就是一个基于体验式学习模型的教学框架,是一种有效的课程设计模式,强调学生主动参与式学习,体现“以学生为中心、教师为主导”教学理念设计,为高质量的有效课堂提供了理论基础。因此,本文旨在探讨以学生为中心的BOPPPS教学模型与DATE监控模式在药理学教学中的应用及其效果。通过实践与研究,发现BOPPPS模型能够有效地提高学生的主动参与度和学习效果,而DATE监控模式则有助于及时发现和解决学生学习中的问题。以供一线教学教师作为教学提供参考和依据,有效提升药理学教学质量。 展开更多
关键词 以学生为中心 BOPPPS教学模型 DATE监控模式 药理学
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Effects of sowing date and ecological points on yield and the temperature and radiation resources of semi-winter wheat 被引量:2
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作者 ZHANG Zhen-zhen CHENG Shuang +7 位作者 FAN Peng ZHOU Nian-bing XING Zhi-peng HU Ya-jie XU Fang-fu GUO Bao-wei WEI Hai-yan ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1366-1380,共15页
Exploring the effects of sowing date and ecological points on the yield of semi-winter wheat is of great significance.This study aims to reveal the effects of sowing date and ecological points on the climate resources... Exploring the effects of sowing date and ecological points on the yield of semi-winter wheat is of great significance.This study aims to reveal the effects of sowing date and ecological points on the climate resources associated with wheat yield in the Rice–Wheat Rotation System.With six sowing dates,the experiments were carried out in Donghai and Jianhu counties,Jiangsu Province,China using two semi-winter wheat varieties as the objects of this study.The basic seedlings of the first sowing date (S1) were planted at 300×10^(4)plants ha^(-1),which was increased by 10%for each of the delayed sowing dates (S2–S6).The results showed that the delay of sowing date decreased the number of days,the effective accumulated temperature and the cumulative solar radiation in the whole growth period.The yields of S1 were higher than those of S2 to S6 by 0.22–0.31,0.5–0.78,0.86–0.98,1.14–1.38,and 1.36–1.59 t ha^(–1),respectively.For a given sowing date,the growth days increased as the ecological point was moved north,while both mean daily temperature and effective accumulative temperature decreased,but the cumulative radiation increased.As a result,the yields at Donghai County were 0.01–0.39 t ha–1lower than those of Jianhu County for the six sowing dates.The effective accumulative temperature and cumulative radiation both had significant positive correlations with yield.The average temperature was significantly negatively correlated with the yield.The decrease in grain yield was mainly due to the declines in grains per spike and 1 000-grain weight caused by the increase in the daily temperature and the decrease in the effective accumulative temperature. 展开更多
关键词 WHEAT YIELD SOWING DATE ECOLOGICAL point
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Phylogeny,molecular evolution,and dating of divergences in Lagerstroemia using plastome sequences 被引量:2
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作者 Jie Wang Wenchuang He +7 位作者 Xuezhu Liao Jin Ma Wei Gao Haoqi Wang Dili Wu Luke R.Tembrock Zhiqiang Wu Cuihua Gu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第2期345-355,共11页
Lagerstroemia L.(Lythraceae)is a widely distributed genus of trees and shrubs native to tropical and subtropical environments from Southeast Asia to Australia,with numerous species highly valued as ornamentals.Althoug... Lagerstroemia L.(Lythraceae)is a widely distributed genus of trees and shrubs native to tropical and subtropical environments from Southeast Asia to Australia,with numerous species highly valued as ornamentals.Although the plastomes of many species in this genus have been sequenced,the rates of functional gene evolution and their effect on phylogenetic analyses have not been thoroughly examined.We compared three plastome sequence matrices to elucidate how differences in these datasets affected phylogenetic analyses.Robust phylogenetic relationships for Lagerstroemia species were reconstructed based on different plastome sequence partitions and multiple phylogenetic methods.Identification of single-nucleotide variants within different genes also provides basic data on the patterns of functional gene evolution in Lagerstroemia and may provide insights into how those mutations affect protein structure and potentially drive divergence via cytonuclear incompatibility.These results as well as analyses of non-synonymous and synonymous mutations,indicate that heterotachic modes of evolution are present in functional plastome genes and should be accounted for in the analyses of molecular evolution.In addition,divergence events within the Lagerstroemia were dated for the first time.Several of the divergence estimates corresponded to well-known Earth history events,such as the reduction in global temperatures at the Eocene/Oligocene boundary.Our analyses conducted in Lagerstroemia here dissects the various patterns in the divergence of Lagerstroemia and may provide a useful guide to help plant breeders,as well as the necessity of using plastomic data and as possible as to combine evidence from morphological characteristics to investigate the complicated interspecies relationship and the evolutionary dynamics of species. 展开更多
关键词 Lagerstroemia L Evolutionary rate Single-nucleotide variants Molecular dating Chloroplast CODON Covarion
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Diffusion of Sm-Nd in Scheelite and its Significance to Isotopic Dating and Tracing 被引量:1
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作者 ZHANG Dongliang Ian MCOULSON +2 位作者 PENG Jiantang LI Shijie WANG Guoqiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期651-661,共11页
As the principal ore mineral in various tungsten(-gold)deposits,scheelite(CaWO_(4))plays an important role in directly dating the timing of ore formation,and in tracing associated material sources through the study of... As the principal ore mineral in various tungsten(-gold)deposits,scheelite(CaWO_(4))plays an important role in directly dating the timing of ore formation,and in tracing associated material sources through the study of its Sm-Nd geochronology and Nd isotopic characteristics.Since the retention of Sm-Nd systematics within scheelite is presently unconstrained,equivocal interpretations for isotopic data resulting from this method have occurred quite often in previous studies that apply these isotopic data.In order to better elucidate the closure of Sm-Nd in scheelite,the kinetics of Sm and Nd within this mineral lattice were investigated through calculation of diffusion constants presented herein.The following Arrhenius relations were obtained:D_(Nd)=4.00exp(-438 kJ·mol^(–1)/RT)cm^(2)/s D_(Sm)=1.85exp(-427 kJ·mol^(–1)/RT)cm^(2)/s showing diffusion rate of Nd is near identical to Sm in scheelite when at the same temperature.However,compared to other rare earth elements(REEs),which have markedly different atomic radii to either Nd or Sm,these are shown to exhibit a great variation in diffusivities.The observed trends in our data are in excellent agreement with the diffusion characteristics of REEs in other tetragonal ABO4 minerals,indicating that ionic radius is a key constraint to the diffusivity of REEs in the various crystal lattices.With this in mind,the same substitution mechanism and a very slight discrepancy in radii will allow us to infer that significant Sm/Nd diffusional fractionation in scheelite is unlikely to occur during most geological processes.Based upon the diffusion data determined herein,Sm and Nd closure temperatures and retention times in scheelite are discussed in terms of diffusion dynamics.Those results suggest that closure temperatures for Sm-Nd within this mineral are relatively high in contrast to the temperature ranges of ore-formation responsible for scheelite-related deposits,and any later thermal environments.It is likely,therefore,that relevant isotopic information could be easily retained under most geological conditions,since initial crystallization of the scheelite.In addition,comparison of this mineral-element pair over a range of temperatures with some other common minerals used as geochronometers(e.g.,zircon and apatite)indicates that Sm-Nd system has a slower diffusive rate in scheelite than for Sr in apatite or Ar in quartz,and only a little faster than for Pb in zircon.It should be noted,within most hydrothermal deposits where zircon has crystallized,its size is typically no more than 100μm,whereas scheelite commonly occurs as macroscopic grains.For this reason,the larger dimensions of scheelite would provide a robust Sm-Nd system more able to resist perturbations,relating to any later thermal process.As such Sm-Nd investigations of scheelite are akin to U-Pb within zircon samples used in isotopic dating.These observations indicate that Sm-Nd age and isotopic information can provide reliable data in all but the most extreme case,especially when data are extracted from macroscopic grains of scheelite that are chosen to be“pristine”(i.e.,free of surface alteration and/or fractures). 展开更多
关键词 Sm-Nd system DIFFUSION SCHEELITE closure temperature isotopic dating
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Trace Elements of Multi-stage Minerals and Titanite U-Pb Dating for the Gneisses from Liansan Island,Sulu UHPM Belt 被引量:1
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作者 SONG Lihao CAO Yuting +4 位作者 XIE Tianhe CHEN Yuyao GAO Yuan WANG Songjie LI Xuping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1640-1656,共17页
Gneisses with anatectic characteristics from the Liansan island in the Sulu UHPM(ultra-high pressure metamorphic)belt were studied for petrography,titanite U-Pb dating and mineral geochemistry.Three origins of garnets... Gneisses with anatectic characteristics from the Liansan island in the Sulu UHPM(ultra-high pressure metamorphic)belt were studied for petrography,titanite U-Pb dating and mineral geochemistry.Three origins of garnets are distinguished:metamorphic garnet,peritectic garnet and anatectic garnet,which are formed in the stages of peak metamorphism,retrograde anatexis and melt crystallization,respectively.The euhedral titanite has a high content of REE and high Th/U ratios,which is interpreted as indicating that it was newly-formed from an anatectic melt.The LA-ICP-MS titanite U-Pb dating yields 214-217 Ma ages for the titanite(melt)crystallization.The distribution of trace elements varies in response to the different host minerals at different stages.At the peak metamorphic stage,Y and HREE are mainly hosted by garnet,Ba and Rb by phengite,Sr,Nb,Ta,Pb,Th,U and LREE by allanite and Y,U and HREE by zircon.During partial melting,Y,Pb,Th,U and REE are released into the melt,which causes a dramatic decline of these element contents in the retrograde minerals.Finally,titanite absorbs most of the Nb,U,LREE and HREE from the melt.Therefore,the different stages of metamorphism have different mineral assemblages,which host different trace elements. 展开更多
关键词 partial melting multi-stage minerals trace element migration titanite U-Pb dating Sulu UHPM belt
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Phylogenetic Relationship and Molecular Divergence Dating Using SRY Gene Polymorphism about Four Ladoum Sheep Lineages in Senegal
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作者 Pape Madiop Sembène Fatimata Mbaye +1 位作者 Mama Racky Ndiaye Mbacké Sembène 《Open Journal of Animal Sciences》 CAS 2023年第2期179-198,共20页
Animal genetic resources are playing a vital role in livestock production and are essential to food security. The present study aims to contribute to a better understanding genetic local sheep breeds and to elucidate ... Animal genetic resources are playing a vital role in livestock production and are essential to food security. The present study aims to contribute to a better understanding genetic local sheep breeds and to elucidate the phylogenetic relationships through the evolution of the SRY gene in four different lineages of Ladoum sheep raised in Senegal. After a brief analysis of genetic diversity, the phylogenetic relationships and molecular dating were inferred through haplotype networks and four phylogenetic reconstruction methods. The different haplotype networks are constructed with NETWORK ver. 5.0.0.0 using the Median-Joining method. Phylogenetic trees were reconstructed using neighbor-joining, maximum parsimony, maximum likelihood and Bayesian inference. The robustness of the nodes in phylogenetic trees of the three first methods was assessed by 1000 bootstraps. For Bayesian inference, the posterior probability distribution of the trees was estimated by 4 MCMC chains. 5,000,000 generations were performed for each of the chains by sampling the different parameters every 1000 generations. Results show a low polymorphism. Haplotypic diversity is much higher than the average nucleotide divergence between all pairs of haplotypes. The majority and central haplotype indicates a close relationship between “Batling” and “Tyson” individuals. “Birahim” lineage is very distinct from the rest. Phylogenetic trees confirm two genetically separate clades between “Birahim” and the other lineages. The period of divergence between “Birahim” lineage versus the common ancestor of the other three lineages was 2504 years ago. The polyphyly revealed in “Birahim” lindicates that this lineage does not contain the common ancestor of all individuals who compose it. It could therefore be derived from two or more sheep breeds with a common ancestor, Ovis aries. The monophyletic clade appears to be a group including a common ancestor and all of its genetic descendants. This group, bringing together the other three lineages, is in the process of being structured into sub-lineages. This study is the first to show that there are only two genetic lines within ladoum sheep in Senegal. 展开更多
关键词 Genetic Diversity Phylogenetic Relationship Molecular dating SRY Gene Sheeps Ladoum Senegal
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Influence of Planting Date on the Incidence and Severity of Leaf Spot Disease in Telfairia occidentalis Hook f.
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作者 Agyingi Lucy Ambang Kebei Andrew Kpu Mbong Grace Annih 《Agricultural Sciences》 2023年第9期1169-1178,共10页
Telfairia occidentalis Hook f. is attacked by a destructive fungal pathogen Epicoccum sorghinum which causes leaf spot disease in the field. In Came-roon, this critically important seed and leaf vegetable is predomina... Telfairia occidentalis Hook f. is attacked by a destructive fungal pathogen Epicoccum sorghinum which causes leaf spot disease in the field. In Came-roon, this critically important seed and leaf vegetable is predominantly culti-vated under natural environmental conditions. An experiment was conducted in 2019 and 2020 during the long and short rainy seasons in Santchou to de-termine the influence of planting dates between seasons on the incidence and severity of leaf spot disease. The design used was a 2 by 4 factorial random-ized complete block design with three replications and four sowing dates. Data for disease incidence and severity documented fortnightly, were submitted to analysis of variance using SPSS version 23, and the means were separated by Duncan’s multiple range test (DMRT) at a 95% confidence interval. Statistical analysis revealed that the long rainy season registered a significantly (p p < 0.05) disease incidences and severities to other planting dates investi-gated. We established that the first three planting dates in the long rainy season could be a management practice to reduce disease prevalence. 展开更多
关键词 Leaf Spot Planting Date SEASON Telfairia occidentalis
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Metallogenic Age and Ore-forming Material Sources of the Dahongshan Fe-Cu Deposit,Yunnan Province:Insights from Molybdenite Re-Os Dating and H-O-S-Pb Isotopes
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作者 YE Zifeng YANG Guangshu +2 位作者 YU Wenxiu CHEN Aibing JIA Fuju 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1698-1718,共21页
The Dahongshan Fe-Cu(-Au)deposit is a superlarge deposit in the Kangdian metallogenic belt,southwestern China,comprising approximately 458 Mt of Fe ores(40%Fe)and 1.35 Mt Cu.Two main types of Fe-Cu(-Au)mineralization ... The Dahongshan Fe-Cu(-Au)deposit is a superlarge deposit in the Kangdian metallogenic belt,southwestern China,comprising approximately 458 Mt of Fe ores(40%Fe)and 1.35 Mt Cu.Two main types of Fe-Cu(-Au)mineralization are present in the Dahongshan deposit:(1)early submarine volcanic exhalation and sedimentary mineralization characterized by strata-bound fine-grained magnetite and banded Fe-Cu sulfide(pyrite and chalcopyrite)hosted in the Na-rich metavolcanic rocks;(2)late hydrothermal(-vein)type mineralization characterized by Fe-Cu sulfide veins in the hosted strata or massive coarse-grained magnetite orebodies controlled by faults.While previous studies have focused primarily on the early submarine volcanic and sedimentary mineralization of the deposit,data related to late hydrothermal mineralization is lacking.In order to establish the metallogenic age and ore-forming material source of the late hydrothermal(-vein)type mineralization,this paper reports the Re-Os dating of molybdenite from the late hydrothermal vein Fe-Cu orebody and H,O,S,and Pb isotopic compositions of the hydrothermal quartz-sulfide veins.The primary aim of this study was to establish the metallogenic age and ore-forming material source of the hydrothermal type orebody.Results show that the molybdenite separated from quartz-sulfide veins has a Re-Os isochron age of 831±11 Ma,indicating that the Dahongshan Fe-Cu deposit experienced hydrothermal superimposed mineralization in Neoproterozoic.The molybdenite has a Re concentration of 99.7-382.4 ppm,indicating that the Re of the hydrothermal vein ores were primarily derived from the mantle.The δ^(34)S values of sulfides from the hydrothermal ores are 2‰-8‰ showing multi-peak tower distribution,suggesting that S in the ore-forming period was primarily derived from magma and partially from calcareous sedimentary rock.Furthermore,the abundance of radioactive Pb increased significantly from ore-bearing strata to layered and hydrothermal vein ores,which may be related to the later hydrothermal transformation.The composition of H and O isotopes within the hydrothermal quartz indicates that the ore-forming fluid is a mixture of magmatic water and a small quantity of water.These results further indicate that the late hydrothermal orebodies were formed by the Neoproterozoic magmatic hydrothermal event,which might be related to the breakup of the Rodinia supercontinent.Mantle derived magmatic hydrothermal fluid extracted ore-forming materials from the metavolcanic rocks of Dahongshan Group and formed the hydrothermal(-vein)type Fe-Cu orebodies by filling and metasomatism. 展开更多
关键词 stable isotopes Re-Os dating ore-forming material Dahongshan Fe-Cu deposit Kangdian region
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In Situ Rb-Sr Dates of Muscovite and Sulfur Isotope of Pyrite from the Yangshan Gold Deposit in Western Qinling,China
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作者 HUANG Yong QI Xianmao +10 位作者 WU Qingsong LI Jianzhong REN Minghua DUAN Liu’an XIONG Tao YANG Zhonghu ZHAO Yang CIREN Lamu WEI Wei DUAN Jilin YAN Mengmeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1475-1489,共15页
Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in China.The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor nati... Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in China.The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor native gold amounts in stibnite-gold quartz veins.Pyrite and arsenopyrite are the major Au-bearing minerals.Hydrothermal muscovite from gold-bearing quartz veins was dated using the in situ Rb-Sr method to determine the formation age of the Yangshan gold deposit.The Rb-Sr isochron date of the muscovite yielded 210.1±5.6 Ma(MSWD=1.2).This date is near the lower end of the period of the mineralized granitic dykes(210.49-213.10 Ma).Two stages of gold enriching process are recognized in the gold-bearing pyrite:the first is incorporated with the Co,Cu,As,Ni enrichment;and the second is accompanied by Bi,Co,Ni,Pb,Cu,Sb concentration.The in-situ sulfur isotopic values of pyrites show a restrictedΔ34s range of-1.43‰to 2.86‰with a mean value of 0.43‰.Trace-element mapping and in-situ sulfur isotopic analysis of pyrite suggest that the sulfur deposits are likely derived from a magmatic source and likely assimilated by sulfur from the sedimentary bedrock.Thus,magmatism plays a critical role in the formation of the Yangshan gold deposit. 展开更多
关键词 Rb-Sr dating trace-element mapping sulfur isotope gold deposit Yangshan Qinling orogenic belt
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Investigation of Aegilops umbellulata for stripe rust resistance,heading date,and the contents of iron,zinc,and gluten protein
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作者 SONG Zhong-ping ZUO Yuan-yuan +5 位作者 XIANG Qin LI Wen-jia LI Jian LIU Gang DAI Shou-fen YAN Ze-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1258-1265,共8页
Aegilops umbellulata(UU)is a wheat wild relative that has potential use in the genetic improvement of wheat.In this study,46 Ae.umbellulata accessions were investigated for stripe rust resistance,heading date(HD),and ... Aegilops umbellulata(UU)is a wheat wild relative that has potential use in the genetic improvement of wheat.In this study,46 Ae.umbellulata accessions were investigated for stripe rust resistance,heading date(HD),and the contents of iron(Fe),zinc(Zn),and seed gluten proteins.Forty-two of the accessions were classified as resistant to stripe rust,while the other four accessions were classified as susceptible to stripe rust in four environments.The average HD of Ae.umbellulata was significantly longer than that of three common wheat cultivars(180.9 d vs.137.0 d),with the exception of PI226500(138.9 d).The Ae.umbellulata accessions also showed high variability in Fe(69.74-348.09 mg kg^(-1))and Zn(49.83-101.65 mg kg^(-1))contents.Three accessions(viz.,PI542362,PI542363,and PI554399)showed relatively higher Fe(230.96-348.09 mg kg^(-1))and Zn(92.46-101.65 mg kg^(-1))contents than the others.The Fe content of Ae.umbellulata was similar to those of Ae.comosa and Ae.markgrafii but higher than those of Ae.tauschii and common wheat.Aegilops umbellulata showed a higher Zn content than Ae.tauschii,Ae.comosa,and common wheat,but a lower content than Ae.markgrafii.Furthermore,Ae.umbellulata had the highest proportion of γ-gliadin among all the species investigated(Ae.umbellulata vs.other species=mean 72.11%vs.49.37%;range:55.33-86.99%vs.29.60-67.91%).These results demonstrated that Ae.umbellulata exhibits great diversity in the investigated traits,so it can provide a potential gene pool for the genetic improvement of these traits in wheat. 展开更多
关键词 Aegilops umbellulata stripe rust resistance heading date Fe and Zn gluten proteins genetic variation
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Modeling Date Palm Trunk Fibers (DPTF) Packed Bed Adsorption Performances for Cadmium Removal from Aqueous Wastewater
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作者 Ahmad S.Awad Banan Hudaib Waid Omar 《Fluid Dynamics & Materials Processing》 EI 2023年第6期1535-1549,共15页
In this study,the potential of a low-cost bio-adsorbent,taken directly from Date Palm Trunk Fibers(DPTF)agricultural wastes,for cadmium ions removal from wastewaters is examined.The performances of this adsorbent are ... In this study,the potential of a low-cost bio-adsorbent,taken directly from Date Palm Trunk Fibers(DPTF)agricultural wastes,for cadmium ions removal from wastewaters is examined.The performances of this adsorbent are evaluated by building breakthrough curves at different bed heights and flow rates while keeping other parameters,such as the initial feed concentration,pH,and particle size,constant.The results indicate that the maximum cadmium adsorption capacity of DTPF can be obtained from the Thomas model as 51.5 mg/g with the most extended mass transfer zone of 83 min at the lowest flow rate at 5 ml/min.The saturation concentrations(NO)and the rate constant(kab)obtained from the BDST(bed depth service time)model are 7022.16 mg/l and 0.0536 l/mg.min,respectively.Using the Yon-Nelsen Model,it is found that operating at a lower flow rate leads to a larger value of the elapsed needed time to reach a 50%breakthrough.The Wolborska model indicates that the bed capacity increases with decreasing the flow rate,and the adsorbent can achieve a greater external mass transfer kinetic coefficient(2.271/min)at a higher flow rate. 展开更多
关键词 Cadmium ions ADSORPTION fixed bed biodorbent POLLUTANT date palm trunk fibers wastewater treatment breakthrough curves MODELING
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Restoration of reservoir diagenesis and hydrocarbon accumulation process by calcite in-situ U-Pb dating and fluid inclusion analysis: A case study on Cretaceous Qingshuihe Formation in Gaoquan Structure, southern Junggar Basin, NW China
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作者 GUI Lili ZHUO Qingong +7 位作者 LU Xuesong YANG Wenxia CHEN Weiyan WU Hai FAN Junjia HE Yinjun CAO Rizhou YU Xiaoqing 《Petroleum Exploration and Development》 SCIE 2023年第6期1386-1397,共12页
The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts hydrocarbon exploration in the lower reservoir assemblage. The lithofacies and diagenesis of reservo... The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts hydrocarbon exploration in the lower reservoir assemblage. The lithofacies and diagenesis of reservoirs in the Cretaceous Qingshuihe Formation in the Gaoquan structure of the Sikeshu Sag, southern Junggar Basin were analyzed. On this basis, the thermal history was calibrated using calcite in-situ U-Pb dating and fluid inclusion analysis to depict the hydrocarbon accumulation process in the Gaoquan structure. The results show that the Qingshuihe reservoir experienced two phases of calcite cementation and three phases of hydrocarbon charging. The calcite cements are dated to be (122.1±6.4) Ma, (14.4±1.0) Ma - (14.2±0.3) Ma. The hydrocarbon charging events occurred at around 14.2-30.0 Ma (low-mature oil), 14.2 Ma (mature oil), and 2 Ma (high-mature gas). The latter two phases of hydrocarbon charging contributed dominantly to the formation of reservoir. Due to the S-N compressive thrust activity during the late Himalayan period since 2 Ma, the traps in the Gaoquan structure were reshaped, especially the effective traps which developed in the main reservoir-forming period were decreased significantly in scale, resulting in weak hydrocarbon shows in the middle-lower part of the structure. This indicates that the effective traps in key reservoir-forming period controlled hydrocarbon enrichment and distribution in the lower reservoir assemblage. Calcite U-Pb dating combined with fluid inclusion analysis can help effectively describe the complex diagenesis and hydrocarbon accumulation process in the central-west part of the basin. 展开更多
关键词 fluid inclusion calcite in-situ U-Pb dating diagenetic sequence hydrocarbon accumulation timing Sikeshu Sag southern Junggar Basin CRETACEOUS Qingshuihe Formation
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