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Effects of acupuncture combined with bone-setting therapy to treat tourette syndrome:a three-arm randomized controlled trial 被引量:1
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作者 LANG Jiawang JIN Lingqing +1 位作者 LUO Jianchang LANG Boxu 《Journal of Traditional Chinese Medicine》 2025年第1期176-183,共8页
OBJECTIVE:To explore the efficacy and safety of acupuncture combined with atlantoaxial joint bone-setting therapy for the treatment of Tourette syndrome.METHODS:We randomly divided 600 patients at a ratio of 1∶1∶1 i... OBJECTIVE:To explore the efficacy and safety of acupuncture combined with atlantoaxial joint bone-setting therapy for the treatment of Tourette syndrome.METHODS:We randomly divided 600 patients at a ratio of 1∶1∶1 into three groups:group A(acupuncture combined with atlantoaxial joint bone setting therapy group),group B(acupuncture group),and group C(tiapride group).After two months of treatment,the Yale global tic severity scale(YGTSS)score reduction,improvement in social function impairment,clinical efficacy,and long-term efficacy in the three groups were compared.RESULTS:After treatment,in the analysis of YGTSS score reduction,social function impairment improvement,the clinical control rate,and long-term efficacy,the results were all Group A>Group B>Group C,with a statistically significant difference(P<0.05).However,the total clinical efficacy of treatment in group A(94.9%)was not significantly different from that in group B(91.8%).Adverse reactions did not occur in groups A and B,and several adverse reactions occurred in 29%(n=58)of the group C patients.CONCLUSION:Compared with traditional drug therapy,acupuncture combined with atlantoaxial joint bone setting therapy has better clinical and long-term efficacy.This treatment strategy can improve the social function of children and prevent adverse reactions to drugs. 展开更多
关键词 Tourette syndrome ACUPUNCTURE atlanto-axial joint tiapride hydrochloride bone setting randomized controlled trial
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Petrogenetic and geochemical characteristics of some auriferous granitoids in the Kumasi Basin, Ghana: Implications for geodynamic settings and controls of orogenic gold mineralization in the Edikan Gold Mine
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作者 Emmanuel D.Sunkari Obed Oppong Theophilus K.Agbenyezi 《Deep Underground Science and Engineering》 2025年第3期406-421,共16页
The Edikan Mine,which consists of Fobinso and Esuajah gold deposits,lies within the Asankrangwa Gold Belt of the Birimian Supergroup in the Kumasi Basin.The metasedimentary rocks in the Basins and the faulted metavolc... The Edikan Mine,which consists of Fobinso and Esuajah gold deposits,lies within the Asankrangwa Gold Belt of the Birimian Supergroup in the Kumasi Basin.The metasedimentary rocks in the Basins and the faulted metavolcanic rocks in the Belts that make up the Birimian Supergroup were intruded by granitoids during the Eburnean Orogeny.This research aims to classify granitoids in the Edikan Mine and ascertain the petrogenetic and geochemical characteristics of some auriferous granitoids in the wider Kumasi Basin,Ghana,to understand the implications for geodynamic settings.A multi-methods approach involving field studies,petrographic studies,and whole-rock geochemical analysis was used to achieve the goal of the study.Petrographic studies revealed a relatively high abundance of plagioclase and a low percentage of K-feldspars(anorthoclase and orthoclase)in the Fobinso samples,suggesting that the samples are granodioritic in nature,while the Esuajah samples showed relatively low plagioclase abundance and a high percentage in K-feldspars,indicating that they are granitic.The granitoids from the study areas are co-magmatic.The granitoids in Esuajah and Fobinso are generally enriched in large ion lithophile elements and light rare earth elements than high field strength elements,middle rare earth elements,and heavy rare earth elements,indicating mixing with crustal sources during the evolution of the granitoids.The granitoids were tectonically formed in a syn-collisional+VAG setting,which implies that they were formed in the subduction zone setting.Fobinso granodiorites showed S-type signatures with evidence of extensive crustal contamination,while the Esuajah granites showed I-type signatures with little or no crustal contamination and are peraluminous.Gold mineralization in the study area is structurally and lithologically controlled with shear zones,faulting,and veining as the principal structures controlling the mineralization.The late-stage vein,V3,in the Edikan Mine is characterized by a low vein angle and is mineralized. 展开更多
关键词 Edikan Mine geodynamic setting GRANITOIDS lithologically controlled structurally controlled subduction zone
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Impact of setting distinct target blood glucose levels on endogenous insulin suppression and pharmacodynamics of insulin preparations
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作者 Hui Liu Ting Li +2 位作者 Xin-Lei Chen Hong-Ling Yu Ye-Rong Yu 《World Journal of Diabetes》 2025年第2期47-54,共8页
BACKGROUND Insulin therapy plays a crucial role in managing diabetes.Regulatory guidelines mandate assessing the pharmacokinetics(PK)and pharmacodynamics(PD)of new insulin formulations with euglycemic clamp techniques... BACKGROUND Insulin therapy plays a crucial role in managing diabetes.Regulatory guidelines mandate assessing the pharmacokinetics(PK)and pharmacodynamics(PD)of new insulin formulations with euglycemic clamp techniques before entry into the market.Typically,blood glucose(BG)levels are maintained at 5%below baseline to suppress endogenous insulin secretion in healthy volunteers.However,in scenarios where BG baseline is relatively low,maintaining it at 5%below baseline can increase hypoglycemic risk.Consequently,we adjusted to maintain it at 2.5%below a baseline of<4.00 mmol/L.It remains uncertain whether this adjustment impacts endogenous insulin inhibition or the PD of study insulin.AIM To evaluate and compare the PD and C-peptide status using two different target BG setting methods.METHODS Data came from euglycemic clamp trials assessing the PK/PD of insulin aspart(IAsp)in healthy participants.Target BG was set at 2.5%below baseline for those with a basal BG of<4.00 mmol/L(group A),and at 5%below baseline for others(group B).The area under the curve(AUC)of IAsp(AUC_(IAsp,0-8 h))and GIR from 0 to 8 hours(AUCGIR,0-8 h)was used to characterize the PK and PD of IAsp,respectively.The C-peptide reduction and PK/PD of IAsp were compared between the two groups.RESULTS Out of 135 subjects,15 were assigned to group A and 120 to group B;however,group B exhibited higher basal Cpeptide(1.59±0.36 vs 1.32±0.42 ng/mL,P=0.006).Following propensity score matching to adjust for basal Cpeptide differences,71 subjects(15 in group A and 56 in group B)were analyzed.No significant differences were observed in demographics,IAsp dosage,or clamp quality.Group B showed significantly higher baseline(4.35±0.21 vs 3.91±0.09 mmol/L,P<0.001),target(4.13±0.20 vs 3.81±0.08 mmol/L,P<0.001),and clamped(4.10±0.17 vs 3.80±0.06 mmol/L,P<0.001)BG levels.Both groups exhibited comparable C-peptide suppression(32.5%±10.0%vs 35.6%±12.1%,P=0.370)and similar IAsp activity(AUCGIR,0-8 h:1433±400 vs 1440±397 mg/kg,P=0.952)under nearly equivalent IAsp exposure(AUC_(IAsp,0-8 h):566±51 vs 571±85 ng/mL×h,P=0.840).CONCLUSION Maintaining BG at 2.5%below a baseline of<4.00 mmol/L did not compromise the endogenous insulin suppression nor alter the observed pharmacodynamic effects of the study insulin. 展开更多
关键词 Euglycemic clamp Target glucose setting Healthy subject C-PEPTIDE PHARMACODYNAMICS Endogenous insulin secretion
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Geochronology and geodynamic setting of the carbonate-hosted Pb-Zn deposits in world-class Sichuan-Yunnan-Guizhou triangle,South China
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作者 Zhongxi Xue Wenxin Shi +2 位作者 Chen Wei Tao Wu Zhilong Huang 《Acta Geochimica》 2025年第1期217-230,共14页
Unraveling the precise mineralization age is vital to understand the geodynamic setting and ore-forming mechanism of the sediment-hosted Pb-Zn deposit;this has long been a challenge.The Sichuan-Yunnan-Guizhou(SYG)tria... Unraveling the precise mineralization age is vital to understand the geodynamic setting and ore-forming mechanism of the sediment-hosted Pb-Zn deposit;this has long been a challenge.The Sichuan-Yunnan-Guizhou(SYG)triangle in the southwestern margin of the Yangtze Block is a globally recognized carbonate-hosted Pb-Zn metallogenic province and also an essential part of the South China low-temperature metallogenic domain.This region has>30 million tons(Mt)Zn and Pb resources and shows the enrichment of dispersed metals,such as Ga,Ge,Cd,Se,and Tl.During the past 2 decades,abundant data on mineralization ages of Pb-Zn deposits within the SYG triangle have been documented based on various radioisotopic dating methods,resulting in significant progress in understanding the geodynamic background and ore formation of Pb-Zn deposits hosted in sedimentary rocks at SYG triangle.This paper provides a comprehensive summary of the geochronological results and Pb-Sr isotopic data regarding Pb-Zn deposits in the SYG triangle,which identified two distinct Pb-Zn mineralization periods influencing the dynamic processes associated with the expansion and closure of the Paleo-Tethys Ocean in the western margin of the Yangtze Block.The predominant phase of Pb-Zn mineralization at SYG triangle spanned from the Middle Triassic to Early Jurassic(226-191 Ma),which was intensely correlated with the large-scale basin fluid transport triggered by the closure of the Paleo-Tethys Ocean and Indosinian orogeny.The secondary Pb-Zn mineralization phase occurred during the Late Devonian to Late Carboniferous and was controlled by extensional structures associated with the expansion of the Paleo-Tethys Ocean.Further investigation is necessary to clarify the occurrence and potential factors involved in the Pb-Zn mineralization events during the Late Devonian to Late Carboniferous. 展开更多
关键词 Sichuan-Yunnan-Guizhou triangle Carbonate hosted Pb-Zn deposit Radioisotopic dating Geodynamic setting Mississippi Valley-type(MVT)
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Intelligent tool setting for vibration cutting process using machine vision and hearing
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作者 Zhihao Ma Junhao Zhao +2 位作者 Jiahui Liu Peiyuan Ding Jianjian Wang 《Nanotechnology and Precision Engineering》 2025年第3期1-7,共7页
Vibration cutting has emerged as a promising method for creating surface functional microstructures.However,achieving precise tool setting is a time-consuming process that significantly impacts process efficiency.This... Vibration cutting has emerged as a promising method for creating surface functional microstructures.However,achieving precise tool setting is a time-consuming process that significantly impacts process efficiency.This study proposes an intelligent approach for tool setting in vibration cutting using machine vision and hearing,divided into two steps.In the first step,machine vision is employed to achieve rough precision in tool setting within tens of micrometers.Subsequently,in the second step,machine hearing utilizes sound pickup to capture vibration audio signals,enabling fine tool adjustment within 1μm precision.The relationship between the spectral intensity of vibration audio and cutting depth is analyzed to establish criteria for tool–workpiece contact.Finally,the efficacy of this approach is validated on an ultra-precision platform,demonstrating that the automated tool-setting process takes no more than 74 s.The total cost of the vision and hearing sensors is less than$1500. 展开更多
关键词 Vibration cutting Automatic tool setting Machine vision Machine hearing
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The Jamaica Handheld Ultrasound Project:a novel longitudinal point-of-care ultrasound curriculum in a resource-limited setting
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作者 Maxime Montour Pranali Sheth +16 位作者 Steve Foo Simone French Tawanda Jones Giselle Watt Brian Kohen Aamir Bandagi Ariella Gartenberg Michael Halperin Trudy-Ann Johnson-Hylton Jason Ifill Alyssia McEwan Jonathan Maik Michelle Montenegro Rie Seu Nicole Leonard-shiu Hugh Wong Trevor Dixon 《World Journal of Emergency Medicine》 2025年第3期262-265,共4页
Point-of-care ultrasound(POCUS) is recognized as a valuable diagnostic tool,especially in resourcelimited settings(RLS).POCUS provides rapid diagnostic information that enables health professionals to make critical de... Point-of-care ultrasound(POCUS) is recognized as a valuable diagnostic tool,especially in resourcelimited settings(RLS).POCUS provides rapid diagnostic information that enables health professionals to make critical decisions at the bedside.^([1]) Despite the welldocumented benefits of POCUS,access to longitudinal,comprehensive training programs and a lack of trainee feedback are barriers to the widespread use of this technology in such settings.^([2]) 展开更多
关键词 health professionals point care ultrasound curriculum technology training feedback Jamaica handheld ultrasound resource limited settings longitudinal
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Noninvasive Breast Cancer Screening Strategies Supported by AI-Based Technologies in Resource-Limited Settings:Is It the Best Opportunity to Strengthen Women's Preferences,Values and Acceptability?
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作者 Wolmark Xiques-Molina Ivan David Lozada-Martinez +1 位作者 Ornella Fiorillo-Moreno Alexis Narvaez-Rojas 《Health Care Science》 2025年第4期310-313,共4页
Breast cancer is the leading cause of cancer-related mortality in women globally,with its incidence continuing to rise,particularly in low-and middle-income countries,presenting a significant public health challenge w... Breast cancer is the leading cause of cancer-related mortality in women globally,with its incidence continuing to rise,particularly in low-and middle-income countries,presenting a significant public health challenge worldwide[1].According to data from the Institute for Health Metrics and Evaluation(IHME)and the World Health Organization(WHO),the gap in access to healthcare services between high-and low-income countries contributes to delayed detection,increased incidence of advanced-stage disease,and,consequently,higher mortality rates(up to 50%higher compared to high-income countries)[1,2].This translates into inequalities in access to screening and early diagnosis methods,which exacerbate the burden of this disease in low-resource settings where infrastructure,funding,and access to trained professionals are limited[3]. 展开更多
关键词 breast neoplasms early detection of cancer mass screening resource-limited settings women's health services
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Study on Automated Placement Setting Agent and Placement Process of Dry Fiber
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作者 WANG Haoyu SUN Ying +3 位作者 CHEN Haoran AN Luling DUAN Shaohua WANG Xianfeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第1期112-122,共11页
During the automated placement process of dry fibers,the positioning and fixation of dry fiber gauze belts are achieved by spraying setting agents.The amount of the setting agent is difficult to control when it is spr... During the automated placement process of dry fibers,the positioning and fixation of dry fiber gauze belts are achieved by spraying setting agents.The amount of the setting agent is difficult to control when it is sprayed manually.Furthermore,it can also affect the permeability of the preform,resin injection and the quality of the vacuum assisted resin infusion(VARI)molding,resulting in a decrease in the mechanical properties of composite materials.This study utilizes dry fiber automated placement equipment and an automated spraying system to manufacture preform structures,followed by VARI process to prepare composite samples with varying setting agent contents.Subsequently,mechanical characterization including interlaminar shear,bending and tensile testing is conducted to investigate the influence of setting agent content on both the manufacturing process and the mechanical properties of composite products.The results show that the interlaminar shear strength,bending strength and tensile strength of the sample gradually decrease with the increase of the content of the setting agent.The optimal setting agent content for automated laying of dry fiber is determined to be 4%-6%,balancing the preformed body’s layup quality and its impact on mechanical properties.Compared with agent-free samples,this range results in reductions of 3% in interlaminar shear strength,9% in bending strength,11% in bending modulus,and 13%-16% in tensile strength. 展开更多
关键词 automated placement technology of dry fiber room temperature setting agent preform preparation vacuum assisted resin infusion(VARI)molding
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Comprehensive pan-cancer analysis of the receptor-interacting protein kinase family expression,genomic alterations,and functional implications
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作者 Wan-Rong Li Xin Li Jian Wang 《Life Research》 2026年第1期35-44,共10页
Background:Receptor-interacting protein kinases(RIPKs)regulate cell death,inflammation,and immune responses,yet their roles in cancer are not fully understood.This study investigates the expression,genomic alterations... Background:Receptor-interacting protein kinases(RIPKs)regulate cell death,inflammation,and immune responses,yet their roles in cancer are not fully understood.This study investigates the expression,genomic alterations,and functional implications of RIPK family members across various cancers.Methods:We collected multi-omics data from The Cancer Genome Atlas and other public databases,including gene expression,copy number variation(CNV),mutation,methylation,tumor mutation burden(TMB),and microsatellite instability(MSI).Differential expression and survival analyses were performed using DESeq2 and Cox proportional hazards models.CNV and mutation data were analyzed with GISTIC2 and Mutect2,and methylation data with the ChAMP package.Correlations with TMB and MSI were assessed using Pearson coefficients,and gene set enrichment analysis was conducted with the MSigDB Hallmark gene sets.Results:RIPK family members show significant differential expression in various cancers,with RIPK1 and RIPK4 frequently altered.Survival analysis reveals heterogeneous impacts on overall survival.CNV and mutation analyses identify high alteration frequencies for RIPK2 and RIPK7,affecting gene expression.RIPK1 and RIPK7 are hypermethylated in several cancers,inversely correlating with RIPK3 expression.RIPK1,RIPK2,RIPK5,RIPK6,and RIPK7 correlate positively with TMB,while RIPK3 shows negative correlations in some cancers.MSI analysis indicates associations with DNA mismatch repair.G ene set enrichment analysis highlights immune-related pathway enrichment for RIPK1,RIPK2,RIPK3,and RIPK6,and cell proliferation and DNA repair pathways for RIPK4 and RIPK5.RIPK family members showed heterogeneous alterations across cancers:for example,RIPK7 was mutated in up to~15%of u terine c orpus e ndometrial c arcinoma and l ung s quamous c ell c arcinoma cases,and RIPK1 and RIPK7 exhibited frequent promoter hypermethylation in multiple tumor types.Several genes displayed context-dependent associations with overall survival and with TMB/MSI.Conclusion:This pan-cancer analysis of the RIPK family reveals their diverse roles and potential as biomarkers and therapeutic targets.The findings emphasize the importance of RIPK genes in tumorigenesis and suggest context-dependent functions across cancer types.Further studies are needed to explore their mechanisms in cancer development and clinical applications. 展开更多
关键词 RIPK family pan-cancer analysis tumor mutation burden microsatellite instability gene set enrichment analysis
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Geographical differentiation of riverine DOM composition and source apportionment:A case study of a riverine network of a mountainous stream,a Plain River,and an artificial canal
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作者 Jun-wei Zhao Shuang-bing Huang +2 位作者 Zhao-xin Su Wei-Chao Huang Yong Qian 《Journal of Groundwater Science and Engineering》 2026年第1期59-68,共10页
To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river ... To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river types within Shandong Province:The mountainous Dawen River,the plain Tuhai River,and the artificial East Grand Canal.The DOM composition was analyzed using Ultraviolet-Visible(UV-Vis)absorption spectroscopy,Excitation-Emission Matrix(EEM)fluorescence spectroscopy,and parallel factor analysis(PARAFAC),while Principal Component Analysis(PCA)was employed to quantify the synergistic effects of natural processes and anthropogenic activities.Results revealed significant spatial heterogeneity in DOM composition and sources.The plain river exhibited the highest aromaticity(humic-like components:43.3%)due to long-term agricultural non-point source inputs and urban wastewater discharge.The mountain stream,shaped by complex terrain and relatively intact ecosystems,was dominated by autochthonous DOM derived from microbial metabolism,with higher Fluorescence Index(FI=2.12)and biological index(BIX=1.35)than other river types.The artificial canal retained protein-like components(64.2%),largely attributed to winter hydrological stagnation and disturbances from shipping activities.Further analysis demonstrated that geographical settings(e.g.,mountain terrain)and anthropogenic activities(e.g.,agriculture,shipping)jointly regulated DOM composition by altering the balance between input and transformation processes.Integrated fluorescence parameters and PCA results suggested differentiated management strategies:protecting ecological integrity in mountain streams to sustain selfpurification,enhancing non-point source interception in plain rivers,and mitigating shipping pollution in canals.This study systematically reveals the natural-anthropogenic coupling mechanisms driving DOM dynamics in northern China rivers,providing critical insights for precision water environment management at the watershed scale. 展开更多
关键词 Dissolved organic matter(DOM) UV-Vis spectroscopy Parallel factor analysis(PARAFAC) Geographical settings Anthropogenic activities
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Effects of Microbial Fertilizer and Compound Feritlizer Mixed Application on Yield and Fruit Quality and Flowering and Fruit Setting of Following Year of Apple 被引量:2
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作者 杨素苗 杜纪壮 +4 位作者 徐国良 石海强 尼群周 俎文芳 秦立者 《Agricultural Science & Technology》 CAS 2016年第3期642-644,共3页
In order to study the application effect of microbial fertilizer and compound fertilizer mixed application on microirrigation apple, three types of fertilizers were applied in spring which were urea(CK, 15 kg/plant)... In order to study the application effect of microbial fertilizer and compound fertilizer mixed application on microirrigation apple, three types of fertilizers were applied in spring which were urea(CK, 15 kg/plant), microbial fertilizer(5.0 kg/plant),microbial fertilizer and compound fertilizer mixed(each 2.5 kg/plant) to study the effect of different fertilizer treatments on yield, fruit quality, flowering and fruit setting of Xinshijie apple. The results showed that application of microbial fertilizer could increase the yield, fruit weight and fruit shape index, significantly increase the flowering rates and inflorescence fruit setting rate of following year, while reduce the fruit hardness and soluble solids content, and the effect of microbial fertilizer and compound fertilizer mixed application on increasing fruit weight and yield was higher than that of microbial fertilizer separate application, the effect of the two was not obvious in other aspects. Therefore, microbial fertilizer could be used instead of some chemical fertilizer and organic fertilizer in apple production to reach the aim of increasing yield and efficiency, and the effect of microbial fertilizer and compound fertilizer mixed application was best. 展开更多
关键词 Microbial fertilizer APPLE YIELD Fruit quality Flowering and fruit setting
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Effect of Extreme Natural High Temperature on Seed Setting Rate of Rice(Oryza sativa L.) at Heading and Flowering Stage 被引量:1
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作者 朱镇 赵庆勇 +5 位作者 张亚东 陈涛 姚姝 周丽慧 于新 王才林 《Agricultural Science & Technology》 CAS 2015年第8期1666-1671,共6页
The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme na... The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme natural high temperature on seed setting rate of different rice cultivar (line). The results showed that the contin- uous high temperature showed certain effects on the seed setting rates of tested materials, and significant differences were shown in seed setting rate among differ- ent rice cultivars (lines). The seed setting rates differed significantly among indica F1 hybrids derived from different sterile and restorer lines, indicating that the sterile and restorer lines had great effects on heat tolerances of different F~ hybrids. The cor- relation analysis showed that the seed setting rates of conventional indica restorer lines and conventional japonica rice cultivars (lines) were negatively related to the daily highest temperature (P〉0.05), and the seed setting rates of indica F1 hybrids were positively related to the seed setting rates of their restorer lines. Total four in- dica restorer lines, including Ninghuiguangkangzhan, Shuhui 527, Chenghui 3203 and Xianyin-8, and four new japonica rice cultivars (lines), including Wuyinjinghui (B2), Nanjing 4//W3660/Nanjing 44 (B12) and Wuyun 2330/JD6011 (B22) were pre- liminarily screened, and their seed setting rates were all close to the normal level (90%). The screened rice cultivars (lines) showed higher heat tolerances. 展开更多
关键词 High temperature seed setting rate Heading and flowering stage RICE
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Metallogenesis related to Mesozoic Granitoids in the Nanling Range, South China and Their Geodynamic Settings 被引量:29
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作者 HUA Renmin CHEN Peirong ZHANG Wenlan YAO Junming LIN Jinfu ZHANG Zhanshi GU Shengyan LIU Xiaodong QI Huawen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第6期810-820,共11页
Affected by the compressive stress from the South-Central (Indo-China) Peninsula, the Indosinian orogenesis, characterized by collision, thrust and uplifting, took place inside the South China Plate during 250-230 M... Affected by the compressive stress from the South-Central (Indo-China) Peninsula, the Indosinian orogenesis, characterized by collision, thrust and uplifting, took place inside the South China Plate during 250-230 Ma. The ages of the Indosinian granitoids in the Nanling Range and vicinity areas are mostly 240-205 Ma, indicating that they were emplaced in both late collision and post-collision geodynamic environments. No important granite-related metallogenesis occurred in this duration. A post-orogenic setting started at the beginning of the Yanshanian Period, which controlled large-scale granitic magmatism and related metallogenesis. This paper makes the first attempt to divide the Yanshanian Period into three sub-periods, i.e. the early, middle and late Yanshanian Periods, based mainly on the features of magmatism, especially granitoids and related metallogenesis and their geodynamic environments. The magmatic association of the Early Yanshanian (about 185-170 Ma) comprises four categories of magmatism, i.e. basalt, bimodal volcanics, A-type granite and intraplate high-K calc-alkaline (HKCA) magmatism, which indicates an extension-thinning of lithosphere and upwelling of mantle material to a relative small and local extent. Pb-Zn, Cu and Au mineralizations associated with HKCA magmatism represents the first high tide of Mesozoic metallogenesis in the Nanling Range area. During the middle Yanshanian, the lithosphere was subjected to more extensive and intensive extending and thinning, and hence mantle upwelling and basaltic magma underplating caused a great amount of crust remelting granitoids. This period can be further divided into two stages. The first stage (170-150 Ma) is represented by large-scale emplacement of crust remelting granites with local tungsten mineralization at its end. The second stage (150-140 Ma) is the most important time of large-scale mineralizations of non-ferrous and rare metals, e.g. W, Sn, Nb-Ta, Bi, Mo, Be, in the Nanling Range area. The late Yanshanian (140-65 Ma) was generally characterized by full extension and breakup of the lithosphere of South China. However, owing to the influence of the Pacific Plate movement, the eastern part of South China was predominated by subduction-related compression, which resulted in magmatism of calc-alkaline and shoshonite series and related metallogeneses of Au, Ag, Pb-Zn, Cu and (Mo, Sn), followed by extension in its late stage. In the Nanling Range area, the late Yanshanian magmatism was represented by granitic volcanic-intrusive complexes and mafic dikes, which are genetically related to volcanic-type uranium and porphyry tin deposits, and the mobilization-mineralization of uranium from pre-existing Indosinian granites. 展开更多
关键词 METALLOGENESIS GRANITOIDS geodynamic setting Yanshanian Period Nanling Range
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Giant Mineral Deposits and Their Geodynamic Setting in the Lanping Basin, Yunnan, China 被引量:22
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作者 XUEChunji LIUShuwen +2 位作者 CHENYuchuan ZENGRong ZHAOShihua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期368-374,共7页
There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, ... There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, Yunnan Province, China. The tabular ore-bodies and some veins hosted in terrestrial clastic rocks of the Mesozoic-Cenozoic age and no outcropping of igneous rocks in the giant deposits lead to the proposal of syngenetic origin, but the giant mineral deposits are not stratabound (e.g. MVT, sandstone- and Sedex-type). They formed in a continental red basin with intense crust movement. The mineralization is controlled by structures and lithology and occurs in different strata, and no sedimentary nature and no exhalative sediments are identified in the deposits. The deposits show some relations with organic matter (now asphalt and petroleum) and evaporates (gypsum). The middle-low-temperature (mainly 110℃ to 280℃) mineralization took place at a depth of about 0.9 km to 3.1 km during the early Himalayan (58 to 67 Ma). The salinity of ore-forming fluids is surprisingly low (1.6% to 18.0 wt% (NaCl)eq). Affected by the collision of the Indian and Eurasian plates, the mantle is disturbed under the Lanping Basin. The large-scale mineralization is closely linked with the geodynamics of the crust movement, the mantle and mantle-flux upwelling and igneous activity. Giant mineral deposits and their geodynamic setting are unique in the Lanping Basin. 展开更多
关键词 giant Jinding Zn-Pb deposit giant Baiyangping Ag-Co-Cu deposit ore geology geodynamic setting Lanping Basin Yunnan Province China
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SHRIMP Zircon U-Pb Ages and Geochemical Characteristics of the Neoproterozoic Granitoids in the Huangling Anticline and Its Tectonic Setting 被引量:13
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作者 魏运许 彭松柏 +5 位作者 蒋幸福 彭中勤 彭练红 李志宏 周鹏 曾雄伟 《Journal of Earth Science》 SCIE CAS CSCD 2012年第5期659-675,共17页
SHRIMP zircon U-Pb dating of the Neoproterozoic Maoping (茅坪) series (Sandouping (三斗坪) rock suite) granites exposed in the southern part of the Huangling (黄陵) anticline shows that the formation time of S... SHRIMP zircon U-Pb dating of the Neoproterozoic Maoping (茅坪) series (Sandouping (三斗坪) rock suite) granites exposed in the southern part of the Huangling (黄陵) anticline shows that the formation time of Sandouping biotite-hornblende tonalite intrusion, Jinpansi (金盘寺) hornblende-biotite tonalite intrusion, and Longtanping (龙潭坪) monzogranite are 863±9, 842±10, and 844±10 Ma, respectively. Their geochemical features include A/CNK=0.98-1.06, from metaluminous to weakly peraluminous, δ=1.37-1.53, Sm/Nd=0.17-0.24, and RbN/YbN=1.1-3.62. These indicate that the granite rocks are supersaturated SiO2 calc-alkaline granitoids. The characteristic of Sr-Nd isotopic composition is that the values of εNd(t) and εsr(t) are -12.4 to -11.0 and 20.2-32.2, respectively. It also suggests that the material source of the granite rocks mainly originated from the crust, and they formed in a volcanic arc tectonic environment. These facts suggest that the occurrence of Neoproterozoic granitoids in the southern part of the Huangling anticline should be related to an arc environment along an active continental margin caused by southward subduction of oceanic crust beneath the northern Yangtze craton, and the formation age is not later than 863 Ma. 展开更多
关键词 Huangling anticline Yangtze plate Neoproterozoic granitoid SHRIMP zircon U-Pbdating geochemistry tectonic setting.
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Fluvial diversity in relation to valley setting in the source region of the Yangtze and Yellow Rivers 被引量:15
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作者 YU Guo-an LIU Le +6 位作者 LI Zhiwei LI Yanfu HUANG Heqing Gary BRIERLEY Brendon BLUE WANG Zhaoyin PAN Baozhu 《Journal of Geographical Sciences》 SCIE CSCD 2013年第5期817-832,共16页
The spatial distribution of valley setting (laterally-unconfined, partly-confined, or confined) and fluvial morphology in the source region of the Yangtze and Yellow Rivers is contrasted and analyzed. The source reg... The spatial distribution of valley setting (laterally-unconfined, partly-confined, or confined) and fluvial morphology in the source region of the Yangtze and Yellow Rivers is contrasted and analyzed. The source region of the Yangtze River is divided into 3 broad sections (I, II and III) based on valley setting and channel gradient, with the upstream and downstream sections being characterized by confined (some reaches partly-confined) valleys while the middle section is characterized with wide and shallow, laterally-unconfined valleys. Gorges are prominent in sections I and III, while braided channel patterns dominate section II. By contrast, the source region of the Yellow River is divided into 5 broad sections (sections I-V) based on valley characteristics and channel gradient. Sections I, II and IV are alluvial reaches with mainly laterally-unconfined (some short reaches partly-confined) valleys. Sections III and V are mainly confined or partly-confined. Greater morphological diversity is evident in the source region of the Yellow River relative to the upper Yangtze River. This includes braided, anabranching, anastomosing, meandering and straight alluvial patterns, with gorges in confined reaches. The macro-relief (elevation, gradient, aspect, valley alignment and confinement) of the region, linked directly to tectonic movement of the Qinghai-Tibet Plateau, tied to climatic, hydrologic and biotic considerations, are primary controls upon the patterns of river diversity in the region. 展开更多
关键词 valley setting fluvial morphology river patterns spatial distribution source region of the Yangtze and Yellow Rivers
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SHRIMP Zircon U-Pb Dating of Alkaline Dykes in the Pobei Area,Beishan Rift,Xinjiang Autonomous Region,China:Implications for Tectonic Setting and Mantle Plume Events 被引量:11
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作者 MAO Jingwen Franco PIRAJNO +1 位作者 ZHANG Zuoheng WAN Yusheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期879-884,共6页
In the Beishan rift in the eastern Tianshan orogen, Xinjiang Province, a N-S-trending dyke swarm is present in the Pobei area. The swarm cuts through the 270-290 Ma mafic-ultramafic intrusions associated with Ni-Cu su... In the Beishan rift in the eastern Tianshan orogen, Xinjiang Province, a N-S-trending dyke swarm is present in the Pobei area. The swarm cuts through the 270-290 Ma mafic-ultramafic intrusions associated with Ni-Cu sulphide mineralization. These mafic-ultramafic intrusions are typically found along E-W major faults in the Tianshan orogenic belts. We report SHRIMP U-Pb dating of zircons from a dyke of alkaline composition, which yielded a mean age of 252~9 Ma. Alkaline dykes of the same age are found in the Altay region of Siberia. This age is younger than the 270-290 Ma intraplate magmatic events that produced the mafic-ultramafic intrusions in the region, but in general agreement with the 250-260 Ma Permian plume event that gave rise to the Siberian traps and the Emeishan flood basalts in SW China. We suggest that there is a link between the Emeishan event and the dyke swarm in the Beishan rift and that the intraplate magmatism at 270-290 Ma reflects an early stage of mantle plume activity. The N-S trending dyke swarm in the Beishan rift may represent a later stage in the evolution of mantle plume activity in the NW and SW of China. We also speculate that in Beishan rift and possibly elsewhere in the Tianshan region, the dykes fed basaltic volcanism, whose products have since been eroded due to the strong uplift of the Tianshan orogen as a result of the IndiaEurasia collision in the Cenozoic. 展开更多
关键词 Alkaline dykes SHRIMP tectonic setting mantle plume China
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Carboniferous Arc Setting in Central Hainan: Geochronological and Geochemical Evidences on the Andesitic and Dacitic Rocks 被引量:9
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作者 Shubo Li Huiying He +2 位作者 Xin Qian Yuejun Wang Aimei Zhang 《Journal of Earth Science》 SCIE CAS CSCD 2018年第2期265-279,共15页
Volcanic rocks in the Bangxi-Chenxing tectonic zone provide important carries for better understanding the Late Paleozoic tectonic evolution in Hainan and its temporal-spatial pattern of the eastern Paleotethyan evolu... Volcanic rocks in the Bangxi-Chenxing tectonic zone provide important carries for better understanding the Late Paleozoic tectonic evolution in Hainan and its temporal-spatial pattern of the eastern Paleotethyan evolution. This paper presents a set of new geochronological and geochemical data on the andesitic and dacitic rocks along the Bangxi-Chenxing tectonic zone in central Hainan. The rep- resentative andesitic and dacitic samples yield similar zircon U-Pb ages of 353^-3 and 351^-7 Ma, respec- tively, being of Early Carboniferous origin. These volcanic rocks are characterized by low TiO2 and high A1203 contents and are enriched in LILEs and LREEs but depletion in HFSEs, along with negative fNd(t) Values of =1.4-- -4.7 and high STSr/S6Sr(i) ratios of 0.707 2-0.710 1. Geochemical signatures suggest that the andesitic and dacitic samples might originate from a metasomatized wedge modified by the slab-derived component in a continental arc setting. In combination with the available data, it is pro- posed for the development of a Carboniferous continental arc in response to the eastern Paleotethyan evolution. The Bangxi-Chenxing tectonic zone might westerly link with the Jinshajiang-Ailaoshan-Song Ma suture zone, constituting an assemblage boundary between the South China and Indochina blocks. 展开更多
关键词 Early Carboniferous volcanic rocks continental arc setting Bangxi-Chenxing zone central Hainan Paleotethyan evolution
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Geochemistry of Carboniferous Sandstones (Sardar Formation), East-Central Iran: Implication for Provenance and Tectonic Setting 被引量:7
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作者 Mohammad KHANEHBAD Reza MOUSSAVI-HARAMI +2 位作者 Asadollah MAHBOUBI Mehdi NADJAFI Mohammad Hosein MAHMUDY GHARAIE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第5期1200-1210,共11页
Geochemical analysis of sandstones from the Sardar Formation (from two stratigraphic successions) in east-central Iran were used for identification of geochemical characterization of sandstones, provenance and tecto... Geochemical analysis of sandstones from the Sardar Formation (from two stratigraphic successions) in east-central Iran were used for identification of geochemical characterization of sandstones, provenance and tectonic setting. Sandstones in the two lithostratigraphic successions have similar chemical compositions suggesting a common provenance. Bulk-rock geochemistry analysis of Carboniferous sandstones from Sardar Formation indicates that they are mainly quartz dominated and are classified as quartzarenites, sublitharenites and subarkoses, derived from acid igneous to intermediate igneous rocks. Discrimination function analysis indicates that the sandstones of Sardar Formation were derived from quartzose sedimentary provenance in a recycled orogenic setting. Also, major and trace elements in sandstones of Sardar Formation (e.g., K2O/Na2O vs. SiO2 ) indicate deposition in a stable passive continental margin (PM). Chemical index of alteration (CIA) for these rocks (65%) suggests a moderate to relatively high degree of weathering in the source area. 展开更多
关键词 PROVENANCE CARBONIFEROUS tectonic setting GEOCHEMISTRY Sardar Formation Iran
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Early Hydration and Setting Process of Fly Ash-blended Cement Paste under Different Curing Temperatures 被引量:8
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作者 ZHANG Wenhua WU Fan ZHANG Yunsheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第3期551-560,共10页
A specially developed ultrasonic measurement apparatus (UMA) was used to in situ monitor the setting process of fly ash blended cement paste. Combined with the results of Vicat Needle tests, isothermal calorimetric me... A specially developed ultrasonic measurement apparatus (UMA) was used to in situ monitor the setting process of fly ash blended cement paste. Combined with the results of Vicat Needle tests, isothermal calorimetric measurement, XRD analysis, SEM morphology and compressive test, the influence of curing temperature (20, 40, 60, and 90 ℃) and fly ash content (0,10%, 20% and 30%) on the setting and hydration process of fly ash blended cement paste was analyzed. The results show that setting and hardening process of fly ash blended cement paste at elevated temperature can be clearly identified into three stages including dormant stage, acceleration stage and deceleration stage. The increasing of curing temperature greatly accelerates the setting and hardening process. However, the content of fly ash does not have significant effect on the setting in condition of 90 ℃. Besides, the initial and final setting time of cement paste is correspondent with the time of duration of dormant stage and the time of UPV value is 1500 m/s (T1500), respectively. Thus, the UMA can be used to determine the initial and final setting time of cementitious material under different curing temperatures. The compressive test results indicate that the paste with 20% fly ash presents higher compressive strength than the plain paste at curing temperatures of 90 ℃. Therefore, appropriate amount of fly ash is beneficial for concrete in the high temperature curing conditions. 展开更多
关键词 ULTRASONIC setting and hardening process curing temperature fly ash MICROSTRUCTURE
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