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CKV-Type矩阵和CKV-Type-B矩阵的扩展垂直线性互补问题解的误差估计
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作者 蒋建新 《吉首大学学报(自然科学版)》 2026年第1期6-12,24,共8页
围绕CKV-type矩阵和CKV-type-B矩阵,研究了扩展垂直线性互补问题解的误差界.以“块矩阵任意子块满足2类矩阵定义”为前提,证明了对原块矩阵进行行重排后,得到的新矩阵中每一子块仍保持与原矩阵子块相同的类型,且重排后的矩阵具有行W-性... 围绕CKV-type矩阵和CKV-type-B矩阵,研究了扩展垂直线性互补问题解的误差界.以“块矩阵任意子块满足2类矩阵定义”为前提,证明了对原块矩阵进行行重排后,得到的新矩阵中每一子块仍保持与原矩阵子块相同的类型,且重排后的矩阵具有行W-性质.在此基础上,推导出2类矩阵对应问题解的误差界表达式. 展开更多
关键词 CKV-type矩阵 CKV-type-B矩阵 扩展垂直线性互补问题
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Source and Evolution of the Ore-Forming Fluids of Carlin-Type Gold Deposit in the Youjiang Basin,South China:Evidences from Solute Data of Fluid Inclusion Extracts 被引量:4
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作者 Xiaoye Jin Chengfu Yang +1 位作者 Jianzhong Liu Wu Yang 《Journal of Earth Science》 SCIE CAS CSCD 2021年第1期185-194,共10页
The source and evolution of ore-forming fluids is important to understand the genesis of Carlin-type gold deposit.Constraints on the source and evolution of ore fluid components by the con-ventional geochemical method... The source and evolution of ore-forming fluids is important to understand the genesis of Carlin-type gold deposit.Constraints on the source and evolution of ore fluid components by the con-ventional geochemical methods have long been a challenge due to the very fine-grained nature and complex textures of hydrothermal minerals in these deposits.In this study,we present the crush-leach analyzed solute data of fluid inclusion extracts within quartz,calcite,realgar,and fluorite from the Shuiyindong,Nibao,and Yata gold deposits in the Youjiang Basin,providing new insights into the source and evolution of ore-forming fluids.The results show that the high molar Cl/Br ratios up to 2508 in fluid inclusion extracts are indicative of a contribution of magmatic hydrothermal fluids.Flu-ids mixing between basinal and magmatic-hydrothermal fluids are evident on the plots of Cl/Br versus Na/K ratios,showing that ore-stage milky quartz near the magmatic-hydrothermal fluids reflects magma origin of the ore-forming fluids,whereas late ore-stage drusy quartz and realgar near the de-fined basinal fluids suggest the later input of basinal fluids in late-ore stage.Although the predominate-ly host rocks in Shuiyindong,Nibao and Yata gold deposit are bioclastic limestone,sedimentary tuff,and calcareous siltstone,respectively,the solute data of fluid inclusion extracts records they underwent the similar fluid-rocks reactions between the Na-rich magmatic hydrothermal fluids and the Ca-and Mg-rich host rocks.This study highlights the solute data of fluid inclusion extracts obtained by crush-leach analyses have the potential to fingerprint the source and evolution of ore-forming fluids of the Carlin-type gold deposit. 展开更多
关键词 solute data fluid inclusion source and evolution of ore-forming fluids Carlin-type gold deposit Youjiang Basin
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Geochemical Tracing of Ore-forming Material Sources of Carlin-type Gold Deposits in the Yunnan-Guizhou-Guangxi Triangle Area --A Case Study of the Application of the Combined Silicon Isotopes Geochemistry and Siliceous Cathodoluminescence Analysis 被引量:1
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作者 LIU Xianfan NI Shijun +2 位作者 LU Qiuxia JIN Jingfu ZHU Laimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第1期30-39,共10页
Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Gui... Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Guizhou-Guangxi triangle area. The study shows that primary silicified quartz is nonluminescent but quartz in host rocks and secondary silicified quartz are luminescent by the action of cathode rays. Correspondingly, silicon isotope compositions of host rocks, ores and hydro6thermal quartz veins are clearly distinguished. In strata from the Middle Triassic to the “Dachang” host bed, δ30Si of the host rocks ranges from 0.0% ?0.3%, while that of primary ore-forming silicified fluids from ?0.1% to ?0.4%; in the Upper Permian and Lower Carboniferous strata and Indosinian diabase host beds, δ30Si of the host rocks is from ?0.1% to ?0.2% and that of the primary silicified quartz veins from 0.3 % ?0.5 %. This pattern demonstrates the following geochemical mineralization process, primary ore-forming siliceous fluids migrated upwards quickly along the main passages of deep-seated faults from mantle to crust and entered secondary faults where gold deposits were eventually formed as a result of permeation and replacement of the siliceous ore-forming fluids into different ore-bearing strata. This gives important evidence for the fact that ore-forming fluids of this type of gold deposits were mainly derived from upper mantle differentiation and shows good prospects for deep gold deposits and geochemical background for large and superlarge gold deposits. 展开更多
关键词 silicon isotope siliceous cathodoluminescence tracing of ore-forming material source Carlin-type gold deposit Yunnan-Guizhou-Guangxi triangle area
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Mercury isotope geochemistry of the Aketashi VMS deposit:Constraints on ore-forming fluid sources
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作者 Ziru Jin Zhengwei Zhang +2 位作者 Chengquan Wu Jinhong Xu Xiyao Li 《Acta Geochimica》 2025年第6期1340-1351,共12页
This study investigates the mercury(Hg)isotope geochemistry of pyrite from the Aketashi volcanic hosted massive sulfide(VMS)deposit in the West Kunlun Orogenic Belt,China,aiming to elucidate the sources of ore-forming... This study investigates the mercury(Hg)isotope geochemistry of pyrite from the Aketashi volcanic hosted massive sulfide(VMS)deposit in the West Kunlun Orogenic Belt,China,aiming to elucidate the sources of ore-forming fluids and the behavior of Hg isotopes during mineralization.The Aketashi deposit is located within a Late Paleozoic back-arc basin,which is characterized by extensive Carboniferous magmatism and hydrothermal activity.Analysis of 19 pyrite ore samples revealed Hg isotope composition with δ^(202)Hg values ranging from−2.48‰to 0.87‰ and Δ^(199)Hg values from−0.02‰ to 0.40‰.The negative δ^(202)Hg values are indicative of isotopic fractionation resulting from hydrothermal processes,whereas the positive Δ^(199)Hg values imply a mixed fluid source comprising both magmatic and seawater-derived components.This study highlights the unique advantage of Hg isotopes in tracing multi-source fluid interactions(e.g.,magmatic vs.seawater-derived)in VMS systems,providing a novel methodology for global metallogenic studies.Our findings not only resolve the longstanding debate on fluid origins at Aketashi but also establish a framework for applying Hg isotopes to other VMS deposits worldwide. 展开更多
关键词 VMS deposits Hg isotopes West Kunlun ore-forming fluid sources
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Ore-forming fluid characteristics and genesis of vein-type lead-zinc mineralization of Xiaohongshilazi deposit,Jilin Province, China
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作者 LI Yong REN Yunsheng +1 位作者 HAO Yujie YANG Qun 《Global Geology》 2017年第4期191-199,共9页
The Xiaohongshilazi mineral deposit in Jilin Province,China,is located in the accretion zone in the northern margin of the North China Block. The deposit contains two types of ore bodies: layered Pb-Zn ore bodies in v... The Xiaohongshilazi mineral deposit in Jilin Province,China,is located in the accretion zone in the northern margin of the North China Block. The deposit contains two types of ore bodies: layered Pb-Zn ore bodies in volcanic rock and vein-hosted Pb-Zn ore bodies controlled by fractures. The vein Pb-Zn ore bodies are strictly controlled by tectonic fracture zones trending in S-N direction,which comprise sulfide veins or sulfidebearing quartz veins distributed along faults or structural fissures. The ores mainly appear mesh-vein and vein structures,and also show solid-solution separation and metasomatic textures. The metal minerals are mainly sphalerite,galena,and pyrite,etc. Wall-rock alteration includes mainly sericitization,chloritization,silicification and carbonatization,etc. Microscope observations and Raman spectroscopy analyses indicate that the oreforming fluid of the vein Pb-Zn ore bodies was mainly magmatic water with low temperature,low salinity,and a shallow depth of metallogenesis( ~ 1.5 km). Sulfur and lead isotope analyses indicate that the sulfide source is mainly formation sulfur or biogenic sulfur,which is similar to the sulfur source of hydrothermal deposit( negative( δ^(34) S values),while the main Pb source was the upper crust with some mantle input. This article argues that the vein Pb-Zn ore body of the Xiaohongshilazi deposit is a low-to medium-temperature hydrothermal vein type related to the formation of a shallow magma chamber. 展开更多
关键词 ore-forming fluid CHARACTERISTICS ore GENESIS hydrothermal VEIN type Xiaohongshilazi Pb-Zn DEPOSIT Jilin Province
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ROLE OF NaCl IN ORE-FORMING OF SAND-SHALE TYPE COPPER DEPOSITS
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作者 Tan Kaixuan and Dai TagenCollege of Resource, Environment and Civil Engineering,Central South University of Technology, Changsha 410083, P. R. China 《中国有色金属学会会刊:英文版》 CSCD 1998年第2期154-159,共6页
ROLEOFNaClINOREFORMINGOFSANDSHALETYPECOPPERDEPOSITS①TanKaixuanandDaiTagenColegeofResource,EnvironmentandCivi... ROLEOFNaClINOREFORMINGOFSANDSHALETYPECOPPERDEPOSITS①TanKaixuanandDaiTagenColegeofResource,EnvironmentandCivilEnginering,Cen... 展开更多
关键词 DISSOLUTION kinetics thermodynamics cuprous CHLORIDE complex NaClsandshale type copper DEPOSITS
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A preliminary study on ore-forming environments of Xianglushan-type iron deposit and the weathering mineralization of Emeishan basalt in Guizhou Province, China
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作者 Guofan Cheng Youping Liu +2 位作者 Hansheng Long Tao Cui Ning Yu 《Acta Geochimica》 EI CAS CSCD 2017年第3期556-565,共10页
Xianglushan-type iron deposits are one of the new types of iron deposits found in the Weining Area of Western Guizhou. The iron-bearing rock system is a paleo-weathered crustal sedimentary(or accumulating) stratum bet... Xianglushan-type iron deposits are one of the new types of iron deposits found in the Weining Area of Western Guizhou. The iron-bearing rock system is a paleo-weathered crustal sedimentary(or accumulating) stratum between the top of the Middle-Late Permian Emeishan basalt formation and the Late Permian Xuanwei formation. Iron ore is hosted in the Lower-Middle part of the rock system. In terms of the genesis of mineral deposit, this type of deposit should be a basalt paleo-weathering crustal redeposit type, very different from marine sedimentary iron deposits or continental weathering crust iron deposits. Based on field work and the analytical results of XRD Powder Diffraction, Electron Probe, Scanner Electron Microscope, etc., the geological setting of the ore-forming processes and the deposit features are illustrated in this paper. The ore-forming environment of the deposit and the Emeishan basalt weathering mineralization are also discussed in order to enhance the knowledge of the universality and diversity of mineralization of the Emeishan Large Igneous Province(ELIP), which may be a considerable reference to further research for ELIP metallogenic theories, and geological research for iron deposits in the paleo-weathering crust areas of the Emeishan basalt,Southwestern, China. 展开更多
关键词 Emeishan basalt paleo-weathering crust Xianglushan-type iron deposit ore-forming environment Weathering mineralization Western Guizhou Province
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Uniqueness of Positive Solutions to Semilinear Equations with Critical Exponential Nonlinearity of Henon Type
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作者 CEN Jianglin ZHU Maochun 《应用数学》 北大核心 2026年第1期80-89,共10页
In this paper,we study the uniqueness of positive solutions to the following semilinear equations{-Δu=λ|x|^(α)ue^(u^(2)),in B_(1),u=0,onδB_(1)ueu2;in B_(1);u=0;on@B_(1);whereλ>0,α>-2;B_(1)denotes the unit ... In this paper,we study the uniqueness of positive solutions to the following semilinear equations{-Δu=λ|x|^(α)ue^(u^(2)),in B_(1),u=0,onδB_(1)ueu2;in B_(1);u=0;on@B_(1);whereλ>0,α>-2;B_(1)denotes the unit disk in R^(2):By delicate and relatively complicated computation of radial solutions to the above equation and the asymptotic expansion of solutions near the boundary of B_(1),the uniqueness of positive solutions is obtained.The results of this paper extend the uniqueness result for the semilinear equation with critical exponential growth in CHEN et al.(2022)to the case that includes a Henon term. 展开更多
关键词 UNIQUENESS Trudinger-Moser inequality Critical exponential Henon type
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PRELIMINARY STUDY ON THE ORE-FORMING CONDITIONS OF THE Au-Pb-QUARTZ VEIN TYPE ORE DEPOSIT,CHINA
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作者 He Zhili, Xu Jiuhua, Yang Zhenlin and Du Jafeng(Dept. of Geol., Univ. of Scie. and Tech. Beijing, 100083 Beijing, China) 《Geotectonica et Metallogenia》 1996年第Z1期13-22,共10页
There are few Au-Pb-Quartz vein type ore deposits in other countries except China. It might be related to the geohistory and geotectonic background. However, this kind of ore deposit has an important economical signif... There are few Au-Pb-Quartz vein type ore deposits in other countries except China. It might be related to the geohistory and geotectonic background. However, this kind of ore deposit has an important economical significance in China. Its formation is due to the dis-tinctive geological conditions of china. Wendong Au-Pb-Quartz type ore deposit including Wenyu and Dongchuang in Xiaoqinling gold field is the most typical. It is a polygenetic and compound ore deposit, Jintongcha and other deposits lying to the west of it in Xiaoqinling area are Au-Pb-Quartz vein type ore deposits. Others of this area lying to the east of Jintongcha are Au-Quartz vein type. This phenomenon stems from the zonnal distribution of minernal de-posits and the different development of the two major minernalzation stages. The results ob-tained from the fluid inclusion research have supported this inference. 展开更多
关键词 ore-forming condition Au-Pb-quartz VEIN ORE deposit China
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Effects of land use type on soil organic carbon in different soil types
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作者 Shunjie Zhu Liangliang Xu +5 位作者 Chengzhong He Yongxing Guo Changqun Duan Xin Jiang Shiyu Li Hailong Yu 《Journal of Integrative Agriculture》 2026年第2期540-552,共13页
Soil organic carbon(SOC)dynamics significantly influence ecosystem carbon source-sink balance,particularly in agroecosystems.However,uncertainty remains regarding optimal land use types for maximizing farmland carbon ... Soil organic carbon(SOC)dynamics significantly influence ecosystem carbon source-sink balance,particularly in agroecosystems.However,uncertainty remains regarding optimal land use types for maximizing farmland carbon storage across different soil types,and identifying effective land management practices for enhanced carbon accumulation is essential for reducing agricultural emissions and strengthening carbon sinks.This study examined SOC variations in eastern Yunnan’s subtropical highlands(2,132 sites),analyzing topsoil(0–20 cm)across five land uses(dryland,irrigated land,forestland,grassland and plantation)of five soil types(red,yellow,yellowbrown,brown,purple).The investigation explored relationships between SOC and edaphic factors(26 elements)to determine SOC influencing factors.The study area demonstrated a mean SOC content of 27.78 g kg^(–1),with distinct spatial heterogeneity characterized by lower values in the southwestern sector and higher concentrations in the northeastern region.Brown soils displayed the highest SOC content(P<0.05),followed by yellow-brown then red,yellow,and purple soils.Irrigation significantly enhanced SOC storage,particularly in brown soils where irrigated land contained 2.2-,2.4-,and 1.6-times higher SOC than forestland,grassland,and dryland,respectively.Similar irrigation benefits occurred in purple,yellow,and yellow-brown soils,indicating moisture limitation as the primary SOC constraint.Notably,SOC exhibited strong positive correlations with nitrogen,sulfur,and selenium.Nitrogen fertilization demonstrated dual benefits:enhancing SOC sequestration and promoting Se enrichment in crops,potentially supporting specialty agriculture.Although land use impacts on SOC varied across soil types(P>0.05),irrigation consistently emerged as the optimal management for carbon sink enhancement.These findings suggest that targeted water management could effectively reduce farmland carbon emissions in moisture-limited subtropical highlands.Strategic nitrogen application offers co-benefits for soil fertility and selenium biofortification,providing practical pathways for climate-smart agriculture in similar ecoregions. 展开更多
关键词 soil organic carbon soil type land use type carbon storage AGROECOSYSTEMS
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Pogorelov type estimates for a class of complex Hessian quotient type equations
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作者 XU Wenzhao CHEN Chuanqiang 《纯粹数学与应用数学》 2026年第1期156-169,共14页
For the complex nonlinear elliptic partial differential equations,it is not easy to prove the Pogorelov type estimates.In this paper,we study a class of complex Hessian quotient type equations in convex cone Γ_(k),wh... For the complex nonlinear elliptic partial differential equations,it is not easy to prove the Pogorelov type estimates.In this paper,we study a class of complex Hessian quotient type equations in convex cone Γ_(k),which is of mixed Hessian type.For the Γ_(k)-admissible solutions,we establish the corresponding Pogorelov estimates with 0≤l<k<n and Pogorelov type estimates with l+1<k=n and l≥0.These extend the previous related results on the real Hessian quotient type equations. 展开更多
关键词 COMPLEX HESSIAN QUOTIENT type EQUATIONS Pogorelov type ESTIMATES Γ_(k)-admissible solutions
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Inadequate glycemic control among patients with type 2 diabetes in Jordan:prevalence and associated factors
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作者 Abeer Amin Mohammad Jafar Alshraideh +1 位作者 Mohammed Ibrahim Yacoub Mohammad A.Abu Sabra 《Frontiers of Nursing》 2026年第1期131-138,共8页
Background:Diabetes mellitus(DM)is a chronic illness with potentially fatal and debilitating consequences.Problems with glycemic management are a major issue that adds an added strain to public health services.Objecti... Background:Diabetes mellitus(DM)is a chronic illness with potentially fatal and debilitating consequences.Problems with glycemic management are a major issue that adds an added strain to public health services.Objectives:The purpose of this study is to evaluate the prevalence of poor glycemic control and its related variables among type 2 diabetes mellitus(T2DM)patients in southern Jordan.Methods:A cross-sectional study was carried out in the Prince Hashem bin Abdullah II Hospital in Jordan's southernmost province.For the period April–July 2024,516 individuals with T2D were enrolled.A structured questionnaire that had been pre-prepared was used to collect data.As an index of glycemic control,a glycated hemoglobin(Hb A1c)7%cut-off point was adopted.Results:Poor glycemic control was prevalent in 81.0%of T2DM individuals.Inadequate glycemic control was significantly worse in non-married patients and those with 10 or more years of diabetes duration,insulin treatment,dyslipidemia,neuropathy,cardiovascular illness,and glomerular filtration rate(GFR=60 m L/min;[P<0.05]).Moreover,dyslipidemia and insulin administration increased the likelihood of poor glycemic control(odds ratio[OR]:2 and 5,respectively)(P<0.05).Conclusions:Inadequate glycemic control was common among the current study par ticipants.To prevent disease consequences and enhance the health of patients with diabetes,health care professionals should pay special attention to related risk factors such as dyslipidemia,neuropathy,cardiovascular disease(CVD),extended illness duration,and insulin usage. 展开更多
关键词 diabetes management glycemic control JORDAN type 2 diabetes
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Genotypes and antibiotic resistance characteristics of Clostridioides difficile in children under 5 years in Yunnan Province,2013-2019
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作者 Jiao Gong Lin-Xia Guo +1 位作者 Yan Zhang Wen-Peng Gu 《Infection Advances》 2026年第2期23-28,共6页
Background:This study aims to analyze the genotypes and antibiotic resistance characteristics of Clostridioides difficile(C.difficile)isolated from children under 5 years old with diarrhea in Yunnan Province.Methods:F... Background:This study aims to analyze the genotypes and antibiotic resistance characteristics of Clostridioides difficile(C.difficile)isolated from children under 5 years old with diarrhea in Yunnan Province.Methods:Fecal samples from children under 5 years of age with diarrhea in Kunming city from 2013-2019 were collected for anaerobic culture,isolation,and identification of C.difficile.The antibiotic susceptibility tests and molecular typing of isolated strains were also performed.Results:44 strains of C.difficile were isolated from 896 fecal samples.Of these,40 strains(90.9%)were positive for both tcdA and tcdB,while 4 strains(9.1%)were negative for both.All isolates were negative for cdtA and cdtB.The isolates were classified into 13 STs,the predominant types were ST3(13 strains,29.5%),ST35(8 strains,18.2%),and ST54(5 strains,11.4%).All the strains were susceptible to metronidazole,amoxicillin/clavulanic acid,vancomycin,and amoxicillin.The highest resistance rate was observed against gentamicin(86.36%),followed by polymyxin E(84.09%),quinupristin-dalfopristin(61.36%),and ceftazidime(36.36%).Some patients with diarrhea had C.difficile co-infections with other pathogens,including norovirus,adenovirus,rotavirus or Salmonella or Escherichia coli.Conclusion:C.difficile strains isolated from children under 5 years of age are mostly toxigenic,and the MLST results are highly diverse.Monitoring and prevention of C.difficile should be strengthened. 展开更多
关键词 Clostridioides difficile CHILDREN DIARRHEA antibiotic resistance multilocus sequence typing
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Clinical Characteristics and Traditional Chinese Medicine Syndrome Types of Inpatients with Gout
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作者 Ping LI Lamei ZHOU 《Medicinal Plant》 2026年第1期46-49,共4页
[Objectives]To analyze the clinical characteristics,distribution of traditional Chinese medicine(TCM)syndrome types,spectrum of comorbidities,and complications among inpatients with gout.[Methods]Data from 592 gout pa... [Objectives]To analyze the clinical characteristics,distribution of traditional Chinese medicine(TCM)syndrome types,spectrum of comorbidities,and complications among inpatients with gout.[Methods]Data from 592 gout patients admitted in the Department of Rheumatology at Wuxi Traditional Chinese Medicine Hospital between January 2018 and December 2024 were retrospectively collected.The data collected encompassed patient gender,age,TCM syndrome types,underlying comorbidities,infection status,and major complications,including renal insufficiency,interstitial lung disease,and osteoporosis.Descriptive statistical analyses were subsequently performed.[Results]Among the 592 inpatients,80.75%were male and 19.25%were female.A total of 94.76%patients had at least one underlying condition,with hypertension(80.74%),cerebral infarction(29.59%),heart disease(24.24%),and diabetes(21.56%)being the most prevalent.The primary TCM syndrome types identified were damp-heat obstruction syndrome(63.51%)and phlegm-stasis obstruction syndrome(21.11%).During hospitalization,20.94%of patients experienced concurrent infections,predominantly pulmonary infections(38.10%).The principal complications observed included renal insufficiency(32.09%),interstitial lung disease(18.75%),and osteoporosis(9.29%).[Conclusions]Inpatients diagnosed with gout often present with complex conditions and a high burden of comorbidities,predominantly cardiovascular and cerebrovascular diseases,as well as metabolic disorders.Additionally,there is a high incidence of infections and renal insufficiency within this population.TCM syndrome types in these patients are primarily characterized by damp-heat obstruction.In clinical practice,a comprehensive management approach that incorporates multidisciplinary collaboration is recommended.Alongside the control of uric acid levels and joint inflammation,proactive screening and management of comorbidities and related complications are essential. 展开更多
关键词 GOUT INPATIENT COMPLICATION TCM syndrome type Renal insufficiency Comprehensive management
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Soil fertility and forest structure influence tree carbon stock depending on mycorrhizal types in a temperate forest
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作者 Zhihui Wang Lu Yang +3 位作者 Juan Wang Xiuhai Zhao Chunyu Zhang Klaus von Gadow 《Journal of Forestry Research》 2026年第1期125-137,共13页
Soil fertility and forest structure influence tree carbon stocks.However,it remains unclear how tree mycorrhizal types affect these relationships.This study addressed the question of how aboveground and belowground tr... Soil fertility and forest structure influence tree carbon stocks.However,it remains unclear how tree mycorrhizal types affect these relationships.This study addressed the question of how aboveground and belowground tree carbon stocks in soils with different mycorrhizal types are affected by soil fertility and forest structure.Tree demographic data were used from a 21.12-ha study area collected over a ten-year period(2009-2019),covering 43species of woody plants and more than 50,000 individuals.Relationships between tree carbon stock,soil fertility and forest structure(stand density,diameter variation,species diversity and spatial distribution)were examined,as well as whether these relationships differed between arbuscular mycorrhiza and ectomycorrhizal mycorrhiza groups in a typical temperate conifer and broad-leaved mixed forest.We found that total tree carbon stock was positively impacted by variations in stand density and tree diameter but negatively influenced by soil fertility,tree species diversity and uniform angle index.Soil fertility promoted carbon stock of trees associated with arbuscular mycorrhiza(AM)but inhibited the carbon stock of trees with ectomycorrhizal mycorrhiza fungi(EcM).Carbon stock of AM trees was mainly influenced by soil fertility,while carbon stock of EcM trees was influenced by stand density.Our findings show that mycorrhizae types mediate the impact of stand structure and soil fertility on tree carbon stocks and provides new evidence on how forest tree carbon stocks may be enhanced based on the types of mycorrhizal associations.Tree species with different mycorrhizal types can be managed in different ways. 展开更多
关键词 Carbon stock Forest structure Soil fertility Mycorrhizal type ABOVEGROUND BELOWGROUND
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Research Progress on Novel Surrogate Indicators of Insulin Resistance in Type 2 Diabetic Kidney Disease
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作者 Jingjing Liang Yuanyuan Jia +1 位作者 Chang Tian Ge Wu 《Journal of Clinical and Nursing Research》 2026年第2期414-420,共7页
Diabetic kidney disease (DKD)is one of the most common and severe microvascular complications of type 2 diabetes mellitus (T2DM). It is also a major cause of end-stage renal disease (ESRD), making early identification... Diabetic kidney disease (DKD)is one of the most common and severe microvascular complications of type 2 diabetes mellitus (T2DM). It is also a major cause of end-stage renal disease (ESRD), making early identification and intervention crucial. Insulin resistance (IR)is a key pathophysiological mechanism of T2DM and plays a central role in the progression of DKD. In recent years, a series of novel surrogate indicators of IR, such as the triglyceride-glucose (TyG) index, TyG-body mass index (TyG-BMI), triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-C), and metabolic score for insulin resistance (METS-IR), have attracted widespread attention due to their simplicity and cost-effectiveness. This article reviews the research progress of novel surrogate indicators of insulin resistance (IR) in type 2 diabetic kidney disease (DKD), aiming to provide references for the early prevention and improved prognosis of DKD. 展开更多
关键词 Insulin resistance type 2 diabetic kidney disease Surrogate indicators REVIEW
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Land use type shapes carbon pathways in Tibetan alpine ecosystems:Characterization of ^(13)C abundance in aggregates and density fractions
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作者 Xin Wan Dangjun Wang +7 位作者 Junya Li Shuaiwen Zhang Linyang Li Minghui He Zhiguo Li Hao Jiang Peng Chen Yi Liu 《Journal of Integrative Agriculture》 2026年第2期448-459,共12页
Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In ... Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In this study,the effect of land use type on carbon storage and fractionation was quantified based on organic carbon and its^(13)C abundance at the microscale of soil aggregates and density fractions in Tibetan alpine ecosystems.The sequence of soil aggregate destruction in the land use types of plantation(13.1%)<shrubland(32.7%)<grassland(47.9%)<farmland(61.8%)shows that plantations strengthen the soil structure.Plantation land had a greater contribution of light fraction organic carbon(28.3%)but a lower contribution of mineral-associated organic carbon(40.6%)to the carbon stock compared to farmland(13.5 and 70.3%).Interestingly,plantation land enhanced the aggregational differentiation of organic carbon and^(13)C in each density fraction,whereas no such phenomenon existed in the soil organic carbon.Carbon isotope analyses revealed that carbon transfer in the plantation land occurred from the light fraction in macroaggregates(–24.9‰)to the mineral-associated fraction in microaggregates(–19.9‰).When compared to the other three land use types,the low transferability of carbon in aggregates and density fractions in plantation land provides a stable carbon pool for the Tibetan Plateau.This study shows that plantations can mitigate global climate change by slowing carbon transfer and increasing carbon storage at the microscale of aggregates and density fractions in alpine regions. 展开更多
关键词 land use type soil aggregate density fractions carbon transfer Tibetan Plateau
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Uniform Attractors for the Kirchhoff Type Suspension Bridge Equation with Nonlinear Damping and Memory Term
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作者 Ling XU Yanni WANG 《Journal of Mathematical Research with Applications》 2026年第1期71-86,共16页
The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and e... The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and existence of uniform attractor under some suitable assumptions on the nonlinear term g(u),the nonlinear damping f(u_(t))and the external force h(x,t).Specifically,the asymptotic compactness of the semigroup is verified by the energy reconstruction method. 展开更多
关键词 uniform attractor Kirchhoff type suspension bridge equation nonlinear damping memory term
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Review of diabetes education intervention targeting parent/caregiver of children with type 1 diabetes
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作者 Ola Hasoneh Jafar A.Alshraideh Diana H.Arabiat 《Frontiers of Nursing》 2026年第1期15-23,共9页
Objective:This review aimed to evaluate existing evidence of educational interventions targeted at parents and caregivers of children with type 1 diabetes(T1D)to improve diabetes management outcomes.Methods:A general ... Objective:This review aimed to evaluate existing evidence of educational interventions targeted at parents and caregivers of children with type 1 diabetes(T1D)to improve diabetes management outcomes.Methods:A general review was conducted with primary caregivers of children younger than 18 with T1D as the population of interest.Journal searches were performed using the CINAHL,EBSCO,Pub Med,Scopus,Science Direct,and Google Scholar,databases for publications between 2017 and 2024,with full text in English.Results:A total of 26 studies were included in the review.Nine of these studies focused on various educational interventions,both technology-based and non-technology-based.By contrast,17 studies examined the impact of these interventions on caregiver outcomes,such as treatment adherence and glycemic control in children with T1D.So,the following research questions guided this review:(1)What is the effectiveness of diabetes education interventions on glycemic control in children with T1D?(2)How do caregiver knowledge and self-efficacy affect diabetes management outcomes?Conclusions:Diabetes interventions highlight the vital role of empowering caregivers of children with T1D with knowledge,skills,and support to improve and enhance their adherence to treatment,knowledge,and self-efficacy that ultimately contribute to better glycemic control of children as reflected by their Hb A1c levels.This review highlights the importance of diabetes education interventions for caregivers of children with T1D.The evidence indicates that such interventions can improve caregiver knowledge,self-efficacy,and glycemic control in children.However,variability in outcomes suggests that fur ther research is needed to identify the most effective educational strategies. 展开更多
关键词 CAREGIVERS CHILDREN diabetes management glycemic control INTERVENTION structured education type 1 diabetes mellitus
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Sex differences in retinal neurovascular changes in type 1 diabetes without retinopathy
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作者 Yao Chen Qian-Xin Li +3 位作者 Tong Zhang Yao Tan Rong-Han Wu Ling Gao 《International Journal of Ophthalmology(English edition)》 2026年第3期509-516,共8页
AIM:To investigate the sex-specific correlation between systemic factors and retinal neurovascular alterations in individuals with type 1 diabetes mellitus(T1DM)who do not exhibit signs of diabetic retinopathy(DR).MET... AIM:To investigate the sex-specific correlation between systemic factors and retinal neurovascular alterations in individuals with type 1 diabetes mellitus(T1DM)who do not exhibit signs of diabetic retinopathy(DR).METHODS:A cohort participant without DR diagnosed with T1DM,underwent comprehensive ophthalmologic evaluation,optical coherence tomography angiography retinal structural and microvascular density analysis,and systemic parameter assessment.Multiple linear regression analysis was used to investigate the impact of systemic parameters on retinal alterations in distinct gender groups.RESULTS:A total of 182 individuals were included,consisting of 85 males(mean age 23.28±12.75y)and 97 females(mean age 22.98±13.68y).Males exhibited significantly greater thickness in both the internal retinal layer and the entire retina compared to females(P<0.01),whereas females had higher densities of deep retinal vessels and choroidal capillaries(P<0.05).Additionally,glycemic control was found to have a notable influence on retinal thickness in males(P<0.05),while insulin function had a more pronounced impact on retinal structure in females(P<0.01).Furthermore,a significant correlation was observed between thyroid function markers and retinal parameters in both male and female(P<0.05).CONCLUSION:Sex differences in alterations in retinal structure and microcirculation are observed in individuals with T1DM prior to the development of clinical DR,with a noted association between these changes and systemic parameters. 展开更多
关键词 type 1 diabetes mellitus diabetic retinopathy gender differences optical coherence tomography angiography
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