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Significance of dormant forms of Helicobacter pylori in ulcerogenesis 被引量:24
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作者 Vasiliy Ivanovich Reshetnyak Tatiana Magomedalievna Reshetnyak 《World Journal of Gastroenterology》 SCIE CAS 2017年第27期4867-4878,共12页
Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ul... Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease(PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However,the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms,but also contribute to the conversion of H. pylori into the resting(dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms,such as S-shaped,C-shaped,U-shaped,and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability. 展开更多
关键词 Helicobacter pylori forms of H. pylori Dormant forms of H. pylori Viable forms of H. pylori Non-viable forms of H. pylori Physiological states of H. pylori Culturable forms of H. pylori Unculturable forms of H. pylor Resuscitation of dormant H. pylori Ulcerogenesis
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Systematic Benchmarking of Topology Optimization Methods Using Both Binary and Relaxed Forms of the Zhou-Rozvany Problem
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作者 Jiye Zhou Yun-Fei Fu Kazem Ghabraie 《Computer Modeling in Engineering & Sciences》 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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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:1
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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》 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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Altitudinal patterns of plant diversity, cover, and life forms in a warm arid mountain: Insights from Sierra de Velasco, Argentina
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作者 Sofia V.LIZARRAGA Omar VARELA Julieta CARILLA 《Journal of Mountain Science》 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
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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》 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(R^(2))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 R^(2) 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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Biological forms and public health implications of Anopheles stephensi:Addressing the urban malaria challenge
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作者 Gaurav Kumar Himmat Singh Shweta Pasi 《Asian Pacific Journal of Tropical Medicine》 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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The Solidifying Power of Myth in Cassirer’s Philosophy of Symbolic Forms
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作者 SHEN Bo 《Journal of Literature and Art Studies》 2025年第3期152-157,共6页
Cassirer argues that humans are animals of symbols,and these symbolic forms encompass not only the science of rational logic but also non-logical elements such as mythology and primitive religions.Previous research on... Cassirer argues that humans are animals of symbols,and these symbolic forms encompass not only the science of rational logic but also non-logical elements such as mythology and primitive religions.Previous research on Cassirer’s philosophy of symbolic forms has primarily focused on philosophical connotations,philosophical thoughts,cultural philosophy,and other aspects,yielding abundant results.By examining mythology within the context of symbolic forms,we discover a force within it,namely,the solidifying power.This solidifying power demands that mythology maintain fixed and established forms during its emergence and development,thereby distinguishing it from other symbolic forms.By exploring the development trends and manifestations of the solidifying power in mythology,we can gain a clearer understanding of the path of human intellectual development from childhood to maturity,thus answering the historical question of human essence. 展开更多
关键词 CASSIRER philosophy of symbolic forms MYTHOLOGY solidifying power
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Representations by Certain Sextenary Quadratic Forms Whose Coefficients Are 1, 2, 3 and 6
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作者 Barış Kendirli 《Advances in Pure Mathematics》 2016年第4期212-296,共85页
Here, we determine formulae, for the numbers of representations of a positive integer by certain sextenary quadratic forms whose coefficients are 1, 2, 3 and 6.
关键词 Sextenary Quadratic forms REPRESENTATIONS Theta Functions Dedekind Eta Function Eisenstein Series Eisenstein forms Modular forms Cusp forms
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如何把SQL*Forms3.0的应用转换到OracleForms4.0
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作者 罗铁坚 陈霞 《计算机应用》 CSCD 1996年第3期62-64,共3页
OracleForms4.0是新一代面向对象的数据库开发工具。本文讨论从SQL*Forms3.0字符方式的应用转到OracleForms4.0基于GUI的应用时所遇到的问题。本文先介绍转换命令,然后介绍OracleF... OracleForms4.0是新一代面向对象的数据库开发工具。本文讨论从SQL*Forms3.0字符方式的应用转到OracleForms4.0基于GUI的应用时所遇到的问题。本文先介绍转换命令,然后介绍OracleForms4.0的新特性,最后讨论触发子。 展开更多
关键词 SQL*forms ORACLE forms 面向对象
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Address forms in Chinese and English-speaking culture
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作者 WANG Xiao-ru 《Sino-US English Teaching》 2008年第5期70-73,共4页
Address form is one of markers of politeness and is an indispensable part of communication. An appropriate address form promotes interpersonal communication smoothly. An address form is polite in one culture, but migh... Address form is one of markers of politeness and is an indispensable part of communication. An appropriate address form promotes interpersonal communication smoothly. An address form is polite in one culture, but might be inappropriate in another culture. The paper contrasts address forms in English and Chinese culture and exolores the reasons for their different choice of address terms. 展开更多
关键词 address forms formal INFORMAL forms of respect forms of humility
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Effect of Nitrogen Application on Contents of Different Forms of Nitrogen in Rice Plants 被引量:10
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作者 莫润秀 江立庚 +6 位作者 郭立 胡均铭 刘开强 周佳民 梁天锋 曾可 丁成泉 《Agricultural Science & Technology》 CAS 2011年第10期1484-1489,共6页
[Objective]The paper was to study the effect of different nitrogen application levels and modes on contents of different forms of nitrogen in rice plants.[Method] Using Guichao 2 and Diejiazhan as test materials,with ... [Objective]The paper was to study the effect of different nitrogen application levels and modes on contents of different forms of nitrogen in rice plants.[Method] Using Guichao 2 and Diejiazhan as test materials,with total nitrogen,protein nitrogen,chlorophyll nitrogen,soluble protein nitrogen,Rubisco nitrogen,free amino acid nitrogen as indicators,the effect of nitrogen application on contents of different forms of nitrogen in rice plants were studied.[Result] The contents of total nitrogen,protein nitrogen,chlorophyll nitrogen,soluble protein nitrogen,Rubisco-N,free amino nitrogen of rice plant during heading and maturity stage increased with the increasing application amount of nitrogen,and their contents would be high under heavy application of spike fertilizer when the application amount of nitrogen was the same.However,application of nitrogen had different impact on different forms of nitrogen,which showed obvious impact on the contents of Rubisco-N and free amino nitrogen.The differences of Rubisco-N and free amino nitrogen content of two varieties during heading and maturity stage under different nitrogen application modes all reached significant or extremely significant level.Correlation analysis showed that total nitrogen content of rice plant had extremely significant correlation with protein nitrogen content during heading and maturity stage in both early and late seasons.[Conclusion] The study provided a theoretical basis for clarifying the regulatory role of nitrogen application on nitrogen absorption and utilization. 展开更多
关键词 Rice(Oryza sativa L.) Nitrogen content Nitrogen application Nitrogen forms
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A Programming Method for Mean Behavior of Fourier Coefficients of Modular Forms on Sparse Sequences
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作者 HU Yuanrui YAO Weili 《数学进展》 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)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)at... Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)attached to f.In this paper,we study the mean value distribution over a specific sparse sequence of positive integers of the following sum∑(a^(2)+b^(2)+c^(2)+d^(2)≤x(a,b,c,d)∈Z^(4))λ_(sym^(j))^(i)f(a^(2)+b^(2)+c^(2)+d^(2))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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针对ASP.net Forms认证的异源重放攻击研究及应对 被引量:2
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作者 孙伟 张永 王占 《计算机应用与软件》 CSCD 2015年第10期315-319,共5页
采用Forms认证的ASP.net网站容易受到重放攻击的威胁。介绍ASP.net Forms认证一般性实施方法,分析Forms认证的原理,给出重放攻击的原理性实施方法,并对重放攻击得逞的原因进行分析。在此基础上,通过引入更加严谨的会话概念,提出基于会... 采用Forms认证的ASP.net网站容易受到重放攻击的威胁。介绍ASP.net Forms认证一般性实施方法,分析Forms认证的原理,给出重放攻击的原理性实施方法,并对重放攻击得逞的原因进行分析。在此基础上,通过引入更加严谨的会话概念,提出基于会话识别的异源重放攻击应对方案。该方案通过对会话的严格管理,识别客户端的变化,适时地要求用户输入原始认证信息,例如,用户名和密码,进行身份认证,达到应对重放攻击的目的。最后,代码实现和理论分析均表明,所提出的应对方案能够有效地应对异源重放攻击。 展开更多
关键词 ASP.NET forms 认证 重放攻击 异源重放攻击
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中国大学英语教师对“Focus-on-Forms”和“Focus-on-Form”教学方法的认知 被引量:45
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作者 张香存 《外语教学》 北大核心 2005年第3期65-68,共4页
语法教学是语言教学中易引起争论的话题。“Focus-on-forms”和“focus-on-form”是语言课堂教学中有关语法教学的两种方法。本文在对“focus-on-forms”和“focus-on-form”有关理论研究回顾的基础上,通过问卷和访谈的形式对浙江省几... 语法教学是语言教学中易引起争论的话题。“Focus-on-forms”和“focus-on-form”是语言课堂教学中有关语法教学的两种方法。本文在对“focus-on-forms”和“focus-on-form”有关理论研究回顾的基础上,通过问卷和访谈的形式对浙江省几所高校的大学英语教师在英语课堂教学中对语法教学的态度及方式进行调查分析。结果显示,大部分教师倾向于focus-on-form的教学方式。 展开更多
关键词 语法教学 focus—on—forms focus-on-form
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Oracle * Forms 4.5中查询功能的实现 被引量:1
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作者 钟映梅 刘绍中 +1 位作者 冯鲲 范双成 《计算机应用》 CSCD 1998年第2期60-61,共2页
本文详细介绍了Oracle*Forms4.5中查询模式的功能,指出了其中所存在的子表不能对主表进行查询的问题。并对该问题给出了一种行之有效的解决方法。
关键词 查询模式 查询 Oracle*forms 数据库
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The Gauss Circle Problem Related to the Fourier Coefficients of Cusp Forms
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作者 CHEN Feng 《Chinese Quarterly Journal of Mathematics》 2025年第3期313-323,共11页
Let f be a Hecke eigenform of even integral weight k for the full modular group SL_(2)(Z).Denote byλ_(f)(n)the n th normalized coefficient of f.The sum of Fourier coefficients of cusp form over the quadratic polynomi... Let f be a Hecke eigenform of even integral weight k for the full modular group SL_(2)(Z).Denote byλ_(f)(n)the n th normalized coefficient of f.The sum of Fourier coefficients of cusp form over the quadratic polynomial m^(2)+n^(2) is considered,i.e.,∑_( m^( 2)+n^( 2))≤λ^(2)_( f)(m^(2)+n^(2))=CX+O(X ^(337/491+ϵ)),here X large enough and C is a constant. 展开更多
关键词 Cusp form Quadratic form L-FUNCTION
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A Study of Variations in Address Forms in the Tinghu Dialect of Yancheng City
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作者 Xingcheng Pan Zhenjun Song 《Journal of Contemporary Educational Research》 2025年第1期227-233,共7页
This study explores the variations in address forms within the Tinghu dialect of Yancheng city.The findings reveal that the ways individuals address one another in this region deviate from the established principles o... This study explores the variations in address forms within the Tinghu dialect of Yancheng city.The findings reveal that the ways individuals address one another in this region deviate from the established principles of tone sandhi theory.In Chinese phonology,it is generally assumed that individual characters serve as fundamental forms based on their standard pronunciations,with real-time pronunciations adapting to phonetic conditions.However,the study of address forms has not traditionally been integrated into this framework.Observations indicate that a wide range of addressing methods is employed in social interactions,reflecting the complexity of regional cultural traits and social dynamics.This research highlights the distinctive features of address forms in the Tinghu dialect,particularly in terms of tone sandhi,vocative expressions,and indirect address.By examining these unique characteristics,the study enhances our understanding of the principles governing tonal changes in Chinese.Furthermore,it offers valuable insights into the preservation and inheritance of regional dialects. 展开更多
关键词 Tone sandhi Address form Vocative Indirect address
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The First Sign Change of Hecke Eigenvalues of Hecke-Maass New Forms
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作者 TANG Heng-cai WANG Ying-nan 《Chinese Quarterly Journal of Mathematics》 2025年第4期401-407,共7页
In this short note, we survey the recent development on the first sign change of Hecke eigenvalues of Hecke-Maass new forms.
关键词 Cusp form Fourier coefficient L-FUNCTION
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VANISHING THEOREMS OF THE BASIC P-HARMONIC FORMS ON COMPLETE FOLIATED RIEMANNIAN MANIFOLDS
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作者 NIE Yan-ci SHEN Zheng-han 《数学杂志》 2025年第3期195-204,共10页
In this paper,we study the basic p-harmonic forms on the complete foliated Riemannian manifolds.By using the method in[1],we show that if the basic mean curvature form is bounded and co-closed,and the transversal curv... In this paper,we study the basic p-harmonic forms on the complete foliated Riemannian manifolds.By using the method in[1],we show that if the basic mean curvature form is bounded and co-closed,and the transversal curvature operator is nonnegative and positive at least one point,then we obtain a vanishing theorem for L^(p)-integrably p-harmonic r-forms. 展开更多
关键词 basic p-harmonic form vanishing theorem foliated Riemannian manifold
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