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Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. I: Deduction and geometric illustration 认领 引用
1
作者 宋光世 《Journal of Chongqing University》 2003年第2期104-108,共5页
Strong and weak limits as well as strong and weak differentials of multi-variable indeterminate forms are discussed based on the thorough exploration of differentiation to solve the strong and weak limits and differen... Strong and weak limits as well as strong and weak differentials of multi-variable indeterminate forms are discussed based on the thorough exploration of differentiation to solve the strong and weak limits and differentials of unitary indeterminate forms. The fruit of this work is going to be reported in three parts. The first part presents the standard analysis on this subject which supplements, systematizes and advances L. Hospital抯 principles on differential calculus by applying special ,general, and limit guaranteeing theories together with K(t) and XhK0 theories. The combination of theoretical analysis and geometric signification makes the derivation intuitional, visual and easy to perceive. 展开更多
关键词 strong limit weak limit strong differential weak differential indeterminate form multi-variable special form general form
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Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. III: Transformations 认领 引用
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作者 宋光世 《Journal of Chongqing University》 2004年第2期86-90,共5页
Various transforms of the indeterminate forms are presented in this part, which include simplification in spherical coordinates, origin translation, axis alteration, transformation of limit conservation and applicatio... Various transforms of the indeterminate forms are presented in this part, which include simplification in spherical coordinates, origin translation, axis alteration, transformation of limit conservation and application of Xh?K0. Fundamental factors for numerical simplification are provided respectively for bi-variable indeterminate forms, tri-variable indeterminate forms and the universal extending multiplier. 展开更多
关键词 spherical coordinate indeterminate form multi-variable special form limit conservation transform
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Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. II: Supplementary annotations and analysis 认领 引用
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作者 SONGGuangshi 《Journal of Chongqing University》 2004年第1期108-112,共5页
Supplementary annotations on special forms 1to 4, discussion on the general characteristics of K(t) and K(t, t), and analyses on two noticeable limits are presented in this part. It is demonstrated that strong and wea... Supplementary annotations on special forms 1to 4, discussion on the general characteristics of K(t) and K(t, t), and analyses on two noticeable limits are presented in this part. It is demonstrated that strong and weak parabolic transforms can be employed to change the standard form of a multi-variable indeterminate form into xmK type, hence to derive the standard formulae of the limit and the differential. 展开更多
关键词 parabolic transform indeterminate form multi-variable special form
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Influence of divergent sampling intensity across plant growth forms on estimating elevational richness patterns and their drivers 认领 引用 被引量：1
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作者 Hongrui Ling Jianqiang Yang +8 位作者 Yannan He Pengwan Zhang Jiangci nongbu Sina laoding Zhenyu Fan Aoxiang Chang Hang Sun Shuang Zhang Zihan Jiang 《Plant Diversity》 SCIE CAS CSCD 2026年第2期330-339,共10页
Numerous studies have demonstrated that sampling intensity can significantly influence the detection of richness patterns and the assessment of the importance of driving factors.However,existing research has primarily... Numerous studies have demonstrated that sampling intensity can significantly influence the detection of richness patterns and the assessment of the importance of driving factors.However,existing research has primarily focused on comparing the influence of sampling intensity across different locations or community types,with less attention paid to its influence across growth forms.Through field surveys on Baima Snow Mountain and bootstrap resampling analyses,we quantified the influence of sampling intensity on plant elevational richness patterns across growth forms(trees,shrubs,and herbs).Our results revealed that with increasing sampling intensity,the error in assessing elevational richness patterns decreased rapidly then stabilized for all growth forms.A similar trend was observed in the estimation of climatic drivers.However,significant variations emerged across different growth forms.The suitable sampling intensity was higher for trees and shrubs than for herbaceous plants.Furthermore,estimation errors for tree richness patterns declined significantly faster with increasing sampling intensity than those for shrubs and herbs.Similarly,the relationship between sampling intensity and error in estimating richness-climate relationships showed significant differences across growth forms.However,these differences were subject to the climate drivers selected.These findings demonstrate that growth-form differences must be considered in elevation-richness surveys.However,our meta-analysis revealed that no current study accounted for this factor in their protocols.Our findings provide empirical evidence for developing growth form-specific sampling protocols,offering practical solutions to improve the accuracy of mountain richness studies and enhance cross-study comparability in elevational gradient research. 展开更多
关键词 Sampling intensity Multi-growth forms Bootstrap sampling Baima Snow Mountain Richness-climate relationships
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Dynamics of cadmium and arsenic in the soil-rice system:Insights from different forms manganese fertilizer application 认领 引用
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作者 Tianyi Yan Quan Zhang +7 位作者 Haifei Chen Jingheng Zhou Qiren Wen Bo Li Qihong Zhu Daoyou Huang Chao Xu Hanhua Zhu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第2期253-263,共11页
Manganese(Mn)is widely used to control cadmium(Cd)and arsenic(As)uptake by rice,but the effects of different Mn forms and concentrations on Cd/As movement in the soil-rice system are unclear.The study investigated the... Manganese(Mn)is widely used to control cadmium(Cd)and arsenic(As)uptake by rice,but the effects of different Mn forms and concentrations on Cd/As movement in the soil-rice system are unclear.The study investigated the mechanisms by which three Mn compounds affected the accumulation of Cd/As in rice under different application rates.MnO2,MnSO4,and MnCO3 treatments significantly reduced grains Cd levels by 27.6%,30.2%,and 28.1%,respectively,while As levels were less consistently affected.Three forms of Mn fertilizers enhanced the conversion of exchangeable to carbonate bound-Cd,which closely related to the increase of soil pH.MnO2 and MnCO3 reduced Cd translocation by increasing Cd/As adsorption on iron plaques,and MnSO4 and MnCO3 decreased Cd translocation by boosting root SOD and Cys levels.Transcriptome analysis revealed that Mn2+ upregulated genes involved in the antioxidant defense system,limited Cd transport by enhancing OsABCC1 and OsHMA3 expression,and promoted As translocation by increasing OsLsi2 expression.Overall,different forms of Mn fertilizers effectively reduced Cd toxicity by fixing Cd in soil carbonate and iron plaques,and restricting Cd transport.Although Mn fertilizers reduced As availability in soil and affected As absorption in rice,they have certain limitations and need to be further explored.These findings reveal the mechanism by which different forms of Mn regulate the fixation and migration behavior of Cd and As,providing new ideas and theoretical basis for reducing the environmental risk of Cd and As. 展开更多
关键词 Manganese forms Cadmium Arsenic Iron plaques Bioavailability Transcriptomic
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Retrieving rare aurora forms from all-sky images via synthetic-to-real progressive learning 认领 引用
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作者 ZHAI Chaoqiang WANG Qian 《Advances in Polar Science》 CSCD 2026年第1期70-80,共11页
Fine-scale structures can be observed in small field-of-view(FOV)auroral observations,but they are often overlooked because they appear only sporadically in all-sky observations.Such forms are of great interest becaus... Fine-scale structures can be observed in small field-of-view(FOV)auroral observations,but they are often overlooked because they appear only sporadically in all-sky observations.Such forms are of great interest because they may embody specific magnetosphere-ionosphere coupling processes,reveal localized energy deposition pathways,and provide new insights into cross-scale plasma dynamics and instabilities.However,their limited spatial extent,transient occurrence,and scarcity in wide-FOV observations make systematic investigation challenging.Traditional manual analysis struggles to capture these subtle structures within vast all-sky datasets,while automated detection faces severe data imbalance and morphological ambiguity.To address these challenges,we propose a synthetic-to-real progressive learning framework for cross-FOV retrieval of rare auroral forms.A Generative Adversarial Network(GAN)is employed to perform cross-FOV transformation between unpaired small-FOV images containing rare aurora forms and all-sky images(ASI)without such structures,thereby generating large numbers of synthetic ASI with rare auroral morphology.These synthetic samples are used to train an initial detection model,which subsequently undergoes iterative fine-tuning through feedback-guided learning:The model performs inference on new all-sky data,and the progressively accumulated real detections are incorporated into the training set.Experimental results demonstrate that the proposed method achieves over 92%detection accuracy on ASI,enabling high-precision retrieval of small-scale auroral structures across large-scale observations.This framework provides a scalable and effective approach to rediscovering rare auroral phenomena in continuous all-sky monitoring,offering new opportunities for exploring the fine-scale dynamics of the upper atmosphere. 展开更多
关键词 fine-scale auroral structures rare auroral forms cross-FOV retrieval Generative Adversarial Network(GAN) synthetic-to-real progressive learning feedback-guided learning
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SOME NEW CHARACTERIZATIONS OF GEODESIC SPHERES IN SPACE FORMS 认领 引用
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作者 Wagner Oliveira COSTA-FILHO 《Acta Mathematica Scientia》 SCIE CSCD 2026年第4期1703-1707,共5页
In this short paper,we obtain a characterization of geodesic spheres in terms of a suitable inequality involving the tangential component of the position vector field for a compact hypersurface in a space form,assumin... In this short paper,we obtain a characterization of geodesic spheres in terms of a suitable inequality involving the tangential component of the position vector field for a compact hypersurface in a space form,assuming appropriate constraints on the associated support function and the Ricci tensor.Some other results are also obtained in case the ambient is the hyperbolic space and the open half-sphere. 展开更多
关键词 compact hypersurface support function space form geodesic sphere
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The Exponential Decaying Noncommutative Differential Forms and Convolution Algebras 认领 引用
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作者 Wen Zhang 《Communications in Mathematical Research》 CSCD 2026年第1期82-96,共15页
We construct an algebra of rapidly decaying C0 functions on an étale (Lie) groupoid, which extends the standard algebra of compactly supported noncommutative differential forms. In particular, using the theory... We construct an algebra of rapidly decaying C0 functions on an étale (Lie) groupoid, which extends the standard algebra of compactly supported noncommutative differential forms. In particular, using the theory of bisections, we prove that this algebra is closed under convolution. This construction clarifies the superconnection proof of Gorokhovsky and Lott. 展开更多
关键词 Noncommutative differential form étale groupoid bisection
λ-BIHARMONIC HYPERSURFACES IN 6-DIMENSIONAL PSEUDO-RIEMANNIAN SPACE FORMS 认领 引用
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作者 DUAN Zhen-ping YANG Chao +1 位作者 LIU Jian-cheng CHEN Jia-rui 《数学杂志》 2026年第1期1-19,共19页
In this paper,we studyλ-biharmonic hypersurfaces Mr5 of 6-dimensional pseudo Riemannian space form Np6(c)with the indexs 0≤p≤6,r=p−1 or p,and constant curvature c.It was proved that if the shape operato... In this paper,we studyλ-biharmonic hypersurfaces Mr5 of 6-dimensional pseudo Riemannian space form Np6(c)with the indexs 0≤p≤6,r=p−1 or p,and constant curvature c.It was proved that if the shape operator of Mr5 is diagonalizable,then the mean curvature is a constant.As an application,we find some types of biharmonic hypersurfaces of Np6(c)are minimal. 展开更多
关键词 λ-biharmonic hypersurface pseudo-Riemannian space form constant mean curvature shape operator minimal
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Inclusive Finance Empowers the Optimization of New Forms of Endowment Insurance:An Exploration on the Path of Bank-Social Organization 认领 引用
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作者 Yizhen Wang Pengwei Ji 《Proceedings of Business and Economic Studies》 2026年第3期33-41,共9页
From the perspective of inclusive finance,banks serve as the core entities empowering endowment insurance services for new forms of employment.Based on reviewing the current development status and existing problems of... From the perspective of inclusive finance,banks serve as the core entities empowering endowment insurance services for new forms of employment.Based on reviewing the current development status and existing problems of endowment insurance for new forms of employment,this paper selects typical cases of bank-social organization collaboration in Fuzhou,Jinan and Zaozhuang,and analyzes the core roles and implementation effects of banks in product customization,channel extension and demand matching.Three major experiences are summarized:scenario-based demand response,inclusive service provision,and normalized mechanism construction.Accordingly,a practical path of collaborative services between Agricultural Bank of China and social organizations is constructed,providing references for solving the endowment security dilemma of groups in new forms of employment. 展开更多
关键词 Inclusive finance Endowment insurance for new forms of employment Bank-social organization collaboration
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Distribution,species richness,and relative importance of different plant life forms across drylands in China 认领 引用 被引量：8
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 SCIE CAS CSCD 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 Drylands Environmental gradients Plant life forms Relative importance Species richness Threshold
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Inconsistent geographical patterns of phylogenetic relatedness among different plant growth forms:A case study in woody and herbaceous angiosperms of China 认领 引用
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作者 Yang-Yang Liu Hong Qian Ya-Dong Zhou 《Journal of Systematics and Evolution》 SCIE CSCD 2025年第3期767-777,共11页
Plants exhibiting different growth forms possess different capabilities in adapting to their respective environments,consequently displaying distinct geographical patterns of phylogenetic relatedness across a broad en... Plants exhibiting different growth forms possess different capabilities in adapting to their respective environments,consequently displaying distinct geographical patterns of phylogenetic relatedness across a broad environmental gradient.Here,we compare the geographical patterns of phylogenetic relatedness between woody and herbaceous angiosperms in China,based on three phylogenetic relatedness metrics,namely,the standardized effect sizes of phylogenetic diversity(PDses),mean pairwise distance(MPDses),and mean nearest taxon distance(MNTDses).Additionally,we explore the effects of three categories of environmental variables(current climate,historical climate change,and environmental heterogeneity)on the geographical patterns of phylogenetic relatedness of both plant groups.Our results indicate that the geographical patterns of phylogenetic relatedness of herbaceous and woody plants are inconsistent,and the deviations of phylogenetic relatedness between woody and herbaceous angiosperms have geographical patterns and vary along environmental gradients.Our study found that environmental variables have a greater influence on the phylogenetic relatedness of herbaceous plants than on that of woody plants,emphasizing that environmental variables,especially current climatic variables,are the primary drivers of the deviations of phylogenetic relatedness between woody and herbaceous angiosperms.In summary,we illustrate the distinct differences in phylogenetic relatedness among plants of different growth forms,providing valuable insights into the driving factors of species coexistence at various spatial scales. 展开更多
关键词 angiosperms China deviation environmental variables growth forms phylogenetic relatedness
Altitudinal patterns of plant diversity, cover, and life forms in a warm arid mountain: Insights from Sierra de Velasco, Argentina 认领 引用 被引量：1
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作者 Sofia V.LIZARRAGA Omar VARELA Julieta CARILLA 《Journal of Mountain Science》 SCIE CSCD 2025年第3期873-887,共15页
Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored varia... Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored variations in composition, diversity, cover,and life forms of vascular plants along a complete altitudinal gradient(1300-4000 m a.s.l) in Sierra de Velasco, an arid mountain in northwestern Argentina.We evaluated the influence of environmental variables on plant diversity and cover. Field sampling was conducted in the northern sector of the Sa. de Velasco,on the western slope in eight 50 m wide altitudinal bands at 400 m elevation intervals. We used rectangular plots(20 × 4 m;n:10/altitudinal band) to register the vascular plants of all the growth forms, and linear transects(20 m long.;n:30/altitudinal band) to quantify the vegetation cover using the point intercept method. Diversity was calculated using hill numbers.Data analysis included non-metric multidimensional scaling(NMDS), indicator species analysis,generalized linear models(GLMs), and variance partitioning analysis. A total of 232 species from 51families and 158 genera were registered. Species composition showed greater similarity at intermediate elevations. Plant diversity and cover exhibited a unimodal distribution, peaking at intermediate elevations(2100-2500 m). In contrast, life forms' distribution showed divergent patterns. Therophytes and succulents predominated at low altitudes,phanerophytes and hemicryptophytes at medium altitudes, and chamaephytes and geophytes at high altitudes. The altitudinal patterns of plant diversity and cover were primarily driven by climatic factors.Conservation efforts in the Sierra de Velasco should focus on the middle and upper zones due to their high biodiversity and vulnerability to climate change. 展开更多
关键词 Elevation gradient Plant diversity Life forms Arid mountains Diversity pattern Climatic drivers
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Enhanced prediction of occurrence forms of heavy metals in tailings:A systematic comparison of machine learning methods and model integration 认领 引用
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作者 Pengxin Zhao Kechao Li +3 位作者 Nana Zhou Qiusong Chen Min Zhou Chongchong Qi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2025年第10期2406-2417,共12页
Tailings produced by mining and ore smelting are a major source of soil pollution.Understanding the speciation of heavy metals(HMs)in tailings is essential for soil remediation and sustainable development.Given the co... Tailings produced by mining and ore smelting are a major source of soil pollution.Understanding the speciation of heavy metals(HMs)in tailings is essential for soil remediation and sustainable development.Given the complex and time-consuming nature of traditional sequential laboratory extraction methods for determining the forms of HMs in tailings,a rapid and precise identification approach is urgently required.To address this issue,a general empirical prediction method for HM occurrence was developed using machine learning(ML).The compositional information of the tailings,properties of the HMs,and sequential extraction steps were used as inputs to calculate the percentages of the seven forms of HMs.After the models were tuned and compared,extreme gradient boosting,gradient boosting decision tree,and categorical boosting methods were found to be the top three performing ML models,with the coefficient of determination(R2)values on the testing set exceeding 0.859.Feature importance analysis for these three optimal models indicated that electronegativity was the most important factor affecting the occurrence of HMs,with an average feature importance of 0.4522.The subsequent use of stacking as a model integration method enabled the ability of the ML models to predict HM occurrence forms to be further improved,and resulting in an increase of R2 to 0.879.Overall,this study developed a robust technique for predicting the occurrence forms in tailings and provides an important reference for the environmental assessment and recycling of tailings. 展开更多
关键词 tailings sequential extraction occurrence forms model comparison stacking ensemble learning
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Systematic Benchmarking of Topology Optimization Methods Using Both Binary and Relaxed Forms of the Zhou-Rozvany Problem 认领 引用
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作者 Jiye Zhou Yun-Fei Fu Kazem Ghabraie 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第6期3233-3251,共19页
Most material distribution-based topology optimization methods work on a relaxed form of the optimization problem and then push the solution toward the binary limits.However,when benchmarking these methods,researchers... Most material distribution-based topology optimization methods work on a relaxed form of the optimization problem and then push the solution toward the binary limits.However,when benchmarking these methods,researchers use known solutions to only a single form of benchmark problem.This paper proposes a comparison platform for systematic benchmarking of topology optimization methods using both binary and relaxed forms.A greyness measure is implemented to evaluate how far a solution is from the desired binary form.The well-known ZhouRozvany(ZR)problem is selected as the benchmarking problem here,making use of available global solutions for both its relaxed and binary forms.The recently developed non-penalization Smooth-edged Material Distribution for Optimizing Topology(SEMDOT),well-established Solid Isotropic Material with Penalization(SIMP),and continuation methods are studied on this platform.Interestingly,in most cases,the grayscale solutions obtained by SEMDOT demonstrate better performance in dealing with the ZR problem than SIMP.The reasons are investigated and attributed to the usage of two different regularization techniques,namely,the Heaviside smooth function in SEMDOT and the power-law penalty in SIMP.More importantly,a simple-to-use benchmarking graph is proposed for evaluating newly developed topology optimization methods. 展开更多
关键词 Topology optimization Zhou-Rozvany problem benchmarking binary forms relaxed forms power-law penalty heaviside smooth function
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Biological forms and public health implications of Anopheles stephensi:Addressing the urban malaria challenge 认领 引用
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作者 Gaurav Kumar Himmat Singh Shweta Pasi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2025年第10期429-430,共2页
Anopheles(An.)stephensi is one of the dominant malaria vectors in India,Bangladesh,Pakistan,Iran,Iraq and some other Asian countries[1].It plays a crucial role in transmitting Plasmodium falciparum and Plasmodium viva... Anopheles(An.)stephensi is one of the dominant malaria vectors in India,Bangladesh,Pakistan,Iran,Iraq and some other Asian countries[1].It plays a crucial role in transmitting Plasmodium falciparum and Plasmodium vivax in India along with its rural counterpart,An.culicifacies.This mosquito species has adapted well to urban and peri-urban environments,making it a significant public health concern in the country.The presence of An.stephensi in urban areas contrasts with other malaria vectors that predominantly inhabit rural regions,thus complicating traditional malaria control strategies.It is well-adapted to human-made environments,breeding in various containers including tanks,cisterns,and barrels used for water storage. 展开更多
关键词 urban malaria plasmodium vivax Plasmodium vivax plasmodium falciparum biological forms malaria vectors Anopheles stephensi public health implications
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Life Forms of Some Representatives of r. Hedysarum Distributed in Central Asia 认领 引用
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作者 Myrzaali Torobaevich Umetaliev Zhazgul Suyunbaevna Abdyrakhmanova +5 位作者 Tazhimamat Kudaiberdievich Erkebaev Dinara Arynbaevna Emilbekova Aida Zhakypovna Dursunbaeva Bibigul Mamatovna Orunbaeva Ainura Manapovna Abzhaparova Kenzhekan Saypidinovna Isakova 《Research in Ecology》 CAS 2025年第4期195-202,共8页
The article examines the life forms of 14 species of the genus Hedysarum belonging to two sections (Obscura andMulticaulia) distributed in Central Asia, including the Central and Western Tien Shan (Talas, Fergana, and... The article examines the life forms of 14 species of the genus Hedysarum belonging to two sections (Obscura andMulticaulia) distributed in Central Asia, including the Central and Western Tien Shan (Talas, Fergana, and Alay ranges),Pamir-Alai and Kopet Dag. The morphological features of mature plants, branching types and a comparative analysisof the characteristics of the studied species—particularly those from the Obscura section (species H. flavescens and H.denticulatum)—were studied. Samples were collected from various types of habitats: grassy, rocky-shallow slopes, redclay outcrops, woody-shrubby thickets, archaea, spruce forests, subalpine meadows, and glacial belts. The life forms ofthe species were identified: H. severzovii and H. pumilum are classified as low-growing, sparsely branched shrubs witha bushy form;H. micropterum and H. wrightianum are classified as short-lived semi-shrubs, transitional from perennialherbaceous plants to short-lived shrubs;H. cephalotes is classified as a perennial turfgrass. The remaining species areperennial herbaceous plants with varying lifespans. 展开更多
关键词 Hedysarum Plant Morphology Central Asia Herbaceous Plants Vital Forms
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Predicted future distributions of endangered Alpine rhododendrons with different life forms in Southwest China under climate change 认领 引用
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作者 Min Wu Wenbin Nie +3 位作者 Wenting Wang Siteng Jiang Renwu Wu Zhiyi Bao 《Ecological Frontiers》 CSCD 2025年第6期1834-1849,共16页
Global climate change poses serious challenges to the distribution and survival of alpine plants,especially in fragmented habitats with low migration potential.This study used the MaxEnt model to predict the current a... Global climate change poses serious challenges to the distribution and survival of alpine plants,especially in fragmented habitats with low migration potential.This study used the MaxEnt model to predict the current and future potential distributions of three endangered Rhododendron species with contrasting life forms in Southwest China—Rhododendron sulfureum(epiphytic shrub),R.fictolacteum(evergreen dwarf shrub),and R.semnoides(tree form)—under current climate and four RCP scenarios(RCP2.6–RCP8.5).Results show:(1)All species are primarily influenced by temperature variables,notably annual temperature range(Bio7),minimum temperature of the coldest month(Bio6),and temperature seasonality(Bio4);(2)Current suitable habitats are concentrated in the Hengduan Mountains and Yunnan-Guizhou Plateau,with shrubs having narrower but more suitable core areas,and the tree species having broader but lower-quality habitats;(3)R.sulfureum faces continuous habitat contraction under all scenarios,while R.fictolacteum and R.semnoides may expand under moderate scenarios but face ecological lags and distribution mismatches;(4)Habitat centroids for all species are projected to shift northward or to higher elevations,driven by life form,dispersal ability,and topographic constraints.These findings highlight life form-dependent responses to climate change and the need for differentiated conservation strategies.Priority should be given to overlapping current and future suitable areas,improving habitat connectivity,and integrating assisted migration and microhabitat management into long-term conservation plans to enhance the resilience of alpine ecosystems. 展开更多
关键词 Endangered alpine rhododendrons Life form differentiation Climate change Ecological niche modeling Potential distribution
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A Programming Method for Mean Behavior of Fourier Coefficients of Modular Forms on Sparse Sequences 认领 引用
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作者 HU Yuanrui YAO Weili 《数学进展》 CSCD 北大核心 2025年第4期709-724,共16页
Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλsymjf(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,symjf)at... Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλsymjf(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,symjf)attached to f.In this paper,we study the mean value distribution over a specific sparse sequence of positive integers of the following sum∑(a2+b2+c2+d2≤x(a,b,c,d)∈Z4)λsymjif(a2+b2+c2+d2)where j≥2 is a given positive integer,i=2,3,4 andαis sufficiently large.We utilize Python programming to design algorithms for higher power conditions,combining Perron's formula,latest results of representations of natural integers as sums of squares,as well as analytic properties and subconvexity and convexity bounds of automorphic L-functions,to ensure the accuracy and verifiability of asymptotic formulas.The conclusion we obtained improves previous results and extends them to a more general settings. 展开更多
关键词 automorphic L-function holomorphic cusp form Fourier coefficient
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La dilution urbaine au prisme de l’espace proxémique;de la discontinuitéau continuum des formes urbaines Urban Dilution through the Prism of Proxemic Space;from Discontinuity to the Continuum of Urban Forms 认领 引用
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作者 Cyril Enault 《Revue Internationale de Géomatique》 2025年第1期881-897,共17页
Considérée souvent en France comme discontinue,la transition du bati urbain-rural est largement envisagécomme continue au niveau international.Si la question de la forme urbaine n’est donc,aujourd’hui... Considérée souvent en France comme discontinue,la transition du bati urbain-rural est largement envisagécomme continue au niveau international.Si la question de la forme urbaine n’est donc,aujourd’hui,plus en suspens du fait des très nombreusesétudesàl’échelle internationale,la limite urbain périurbain et rural isoléconvient d’être néanmoins encore réinterrogée.La notion de proxémique développée dans les années 1970,pourrait permettre une résolution du problème.Utiliser cette notion pour revoir la métrique géographique pourrait permettre de réviser la limite urbain-campagne et raisonner alors sur un espace continu au-delàmême des limites du périurbain. 展开更多
关键词 Proxémique forme urbaine dilution continuité discontinuité
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