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交互式数字叙事:加拿大Writing New Body Worlds阅读治疗新探索
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作者 牟晓青 于志涛 《图书馆论坛》 CSSCI 北大核心 2024年第4期222-230,F0003,共10页
文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性... 文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性健康干预。基于数据与计算的精准化阅读治疗是数字人文视角下的新变革,更具推广应用价值;以在线阅读平台建设为依托,推进实施平台化的阅读和治疗应成为未来发展方向之一;基于阅读形态与体验因技术赋能而改变的现状,图书馆应发挥引领作用,积极收集、创建或协助创建数字故事,推进阅读推广、服务与治疗的融合性发展,成为社区建设促进者、历史欣赏者和社区参与倡导者,也使阅读借助交互式数字叙事这一新载体,更好地发挥变革的力量,促进健康与幸福。 展开更多
关键词 交互式数字叙事 阅读治疗 Writing new Body Worlds 加拿大
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网络新媒体视阈下客家议题在日传播特征分析——基于日本Google News的考察
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作者 李晓霞 周巍 《肇庆学院学报》 2024年第1期116-123,共8页
以日本Google News中的客家相关日文报道为语料,通过文本挖掘工具KH Coder进行文本数据挖掘,发现日本网络新闻媒体的客家议题日文报道具有分布零散性及以图片报道为主的特点。报道关注的客家区域主要涉及台湾地区、福建、香港地区、广... 以日本Google News中的客家相关日文报道为语料,通过文本挖掘工具KH Coder进行文本数据挖掘,发现日本网络新闻媒体的客家议题日文报道具有分布零散性及以图片报道为主的特点。报道关注的客家区域主要涉及台湾地区、福建、香港地区、广东等地,其中,台湾地区的客家关注度最高。报道聚焦客家的观光旅游、产业振兴、客家书籍出版等相关内容,形成了客家传统建筑类、台湾地区客家文化交流类、客家文学作品推介类、客家观光旅游类等四大主要议题。本文提出要充分运用Google News等网络新媒体强大的技术功能和传播优势加大客家文化的传播力度。 展开更多
关键词 网络新媒体 客家文化 日本传播 Google news KH Coder
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Cyclic shear behavior of en-echelon joints under constant normal stiffness conditions 被引量:1
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作者 Bin Wang Yujing Jiang +3 位作者 Qiangyong Zhang Hongbin Chen Richeng Liu Yuanchao Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3419-3436,共18页
To reveal the mechanism of shear failure of en-echelon joints under cyclic loading,such as during earthquakes,we conducted a series of cyclic shear tests of en-echelon joints under constant normal stiffness(CNS)condit... To reveal the mechanism of shear failure of en-echelon joints under cyclic loading,such as during earthquakes,we conducted a series of cyclic shear tests of en-echelon joints under constant normal stiffness(CNS)conditions.We analyzed the evolution of shear stress,normal stress,stress path,dilatancy characteristics,and friction coefficient and revealed the failure mechanisms of en-echelon joints at different angles.The results show that the cyclic shear behavior of the en-echelon joints is closely related to the joint angle,with the shear strength at a positive angle exceeding that at a negative angle during shear cycles.As the number of cycles increases,the shear strength decreases rapidly,and the difference between the varying angles gradually decreases.Dilation occurs in the early shear cycles(1 and 2),while contraction is the main feature in later cycles(310).The friction coefficient decreases with the number of cycles and exhibits a more significant sensitivity to joint angles than shear cycles.The joint angle determines the asperities on the rupture surfaces and the block size,and thus determines the subsequent shear failure mode(block crushing and asperity degradation).At positive angles,block size is more greater and asperities on the rupture surface are smaller than at nonpositive angles.Therefore,the cyclic shear behavior is controlled by block crushing at positive angles and asperity degradation at negative angles. 展开更多
关键词 En-echelon joint Cyclic shear tests Shear stress normal displacement Constant normal stiffness(CNS)
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Influencing Factors of Cultivation and Improvement of College Students Innovation and Entrepreneurship Ability under the New Normal
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作者 Shuli SONG 《Asian Agricultural Research》 2023年第6期21-23,共3页
The cultivation of innovative and entrepreneurial talents is an effective guarantee to meet the strategic needs of national development under the new normal,promote the construction of an innovative country and the de... The cultivation of innovative and entrepreneurial talents is an effective guarantee to meet the strategic needs of national development under the new normal,promote the construction of an innovative country and the development of universities themselves.Combined with the questionnaire survey of colleges and universities in Heilongjiang Province,this paper analyzed factors such as the understanding of the connotation of innovation and entrepreneurship,the thinking and awareness of innovation and entrepreneurship,the demand for training methods of innovation and entrepreneurship,and the approaches to acquire knowledge and capabilities of innovation and entrepreneurship.On this basis,it came up with recommendations for promoting the cultivation of innovative and entrepreneurial talents in colleges and universities,to provide an objective basis for the construction of innovative and entrepreneurial talent training models,so as to promote the effective cultivation of innovative and entrepreneurial talents in colleges and universities. 展开更多
关键词 new normal Innovation and entrepreneurship Talent cultivation
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Stressors in Nurse Students’ Formation in the New Normality Post COVID-19
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作者 Nancy Stephany Viorato-Romero Graciela González-Juárez +1 位作者 Alba Luz Robles-Mendoza Diana Cecilia Tapia-Pancardo 《Open Journal of Nursing》 2023年第7期399-410,共12页
Background: Mental health has been impaired and at risk due to the worldwide COVID-19 pandemic. The consequences due to confinement impacted every scenario, which directly influenced the daily routine of nurse student... Background: Mental health has been impaired and at risk due to the worldwide COVID-19 pandemic. The consequences due to confinement impacted every scenario, which directly influenced the daily routine of nurse students;in each setting students faced stressors that trigger fear, anxiety and others, since being in confinement learning of topics moved to the home, laboratory practices in hospitals were cancelled leaving the room that is uncertain up to their return to in-person activities. It is important to highlight the need for innovation and strengthening of theoretical-pedagogic aspects centered at the student’s context as a human being with their own needs and problems, who will interact with others in the continuous process of health-illness. Objective: the aim was to identify the stressors in the nurse students’ formation in the new normality post-COVID-19. Methods: Qualitative and phenomenological research with 27 participants aged 20 - 25 years, nurse students of a public university. The information collection was through four focal groups of 6-7 members each, data analysis was done according to Miles & Huberman after signed informed consent of each participant, and authorized by the chairperson of the Nurse’ career. Results: Category 1, Cumulative stressors with sub-categories 1.1 Uncertainty, 1.2 Isolation, 1.3 Invisibility, 1.4 Mockery, 1.5 Exclusion. Category 2, Expectancy states with sub-categories 2.1 Low self-esteem, 2.2 Insecurity, 2.3 Anxiety, 2.4 Depression, 2.5 Temporary leave, 2.6 Search for authenticity. Category 3, Internalization processes with sub-categories 3.1 Social rejection, 3.2 Self-censorship, 3.3 Discrediting, 3.4 Disempowerment. Category 4, Academic aspects affected with sub-categories 4.1 Deficient studying habits, 4.2 Deficient assimilations of knowledge, 4.3 Archived knowledge in the computer, 4.4 Absence of practice in previous semesters. Conclusion: Once identified the stressors in nurse students in the new normality post-COVID-19, it will allow the creation of settings that help in getting confidence for students, i.e., a safe surrounding promotes the development of abilities and competencies during formation, as well as recommendations of teachers in the classroom and laboratories that contribute to filling space that students perceive as empty, and to intensifying the companionship in clinical settings where students perceive most aggressiveness. 展开更多
关键词 Stressors Nurse Students’ Formation new normality Post COVID-19
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Boehmeria nivea var. strigosa (Urticaceae), a new variety from Southwest China 被引量:1
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作者 ZHAO Ying Richard I.MILNE +2 位作者 LI Zhipeng Amos KIPKOECH WU Zengyuan 《广西植物》 CAS CSCD 北大核心 2024年第9期1617-1624,I0001-I0006,共14页
Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly charact... Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie. 展开更多
关键词 Boehmeria nivea MORPHOLOGY molecular phylogeny new variety Southwest China YUNNAN
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New direction for surgery:Super minimally invasive surgery 被引量:2
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作者 En-Qiang Linghu 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1676-1679,共4页
The top goal of modern medicine is treating disease without destroying organ structures and making patients as healthy as they were before their sickness.Minimally invasive surgery(MIS)has dominated the surgical realm... The top goal of modern medicine is treating disease without destroying organ structures and making patients as healthy as they were before their sickness.Minimally invasive surgery(MIS)has dominated the surgical realm because of its lesser invasiveness.However,changes in anatomical structures of the body and reconstruction of internal organs or different organs are common after traditional surgery or MIS,decreasing the quality of life of patients post-operation.Thus,I propose a new treatment mode,super MIS(SMIS),which is defined as“curing a disease or lesion which used to be treated by MIS while preserving the integrity of the organs”.In this study,I describe the origin,definition,operative channels,advantages,and future perspectives of SMIS. 展开更多
关键词 Super minimally invasive surgery Minimally invasive surgery Treatment mode Traditional Surgery new direction for surgery
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Exploring the Internal Audit Practices of Electric Power Enterprises in the Context of the New Economic Normal
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作者 Yi Huang 《Proceedings of Business and Economic Studies》 2023年第5期20-25,共6页
In the current economic landscape characterized by a decelerating domestic economy,rising investments,and an extended project construction timeline,power generation enterprises must enhance their internal audit effort... In the current economic landscape characterized by a decelerating domestic economy,rising investments,and an extended project construction timeline,power generation enterprises must enhance their internal audit efforts to sustain their competitive edge in business development.Addressing systemic shortcomings methodically and practically can enhance the internal audit effectiveness within electric power enterprises and contribute to the steady enhancement of their production and operation performance. 展开更多
关键词 ELECTRICITY ECONOMY new economic normal Internal audit
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Comprehensive Evaluation of Flower Border Application Value of New and Superior Plants in Hefei Area 被引量:1
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作者 MENG Yi ZHAO Zhiyan +1 位作者 LIANG Tingwu LU Zhaoliang 《Journal of Landscape Research》 2024年第2期69-71,76,共4页
An analytic hierarchy process(AHP)was employed to assess the applicability of 18 new and superior varieties of flowers in Hefei City flower border applications.A total of 12 indicators were selected from three distinc... An analytic hierarchy process(AHP)was employed to assess the applicability of 18 new and superior varieties of flowers in Hefei City flower border applications.A total of 12 indicators were selected from three distinct aspects of adaptability,ornamental characteristics and use traits,in order to establish a comprehensive evaluation model.The results demonstrate that grade I(J≥2.685)exhibits excellent application value,encompassing six species of plants,such asHydrangeamacrophylla‘Endless Summer’;grade II(2.684≤J≤2.420)is also of notable application value,encompassing five species of plants,such asCallistemonrigidus;grade III(2.419≤J≤2.615)is of average application value,including five species of plants,such asCrocosmiacrocosmiflora;grade IV(J≤2.16)is of relatively poor application value.The evaluation results may be utilized as a theoretical reference for the promotion of new and superior varieties in the flower border of Hefei. 展开更多
关键词 Analytic hierarchy process(AHP) new and superior variety Application value Comprehensive evaluation
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Endoscopic diagnosis and management of gallbladder carcinoma in minimally invasive era:New needs,new models
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作者 La-Cuo Deqing Jun-Wen Zhang Jian Yang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第11期4333-4337,共5页
Gallbladder cancer(GBC)is a rare and lethal malignancy;however,it represents the most common type of biliary tract cancer.Patients with GBC are often diagnosed at an advanced stage,thus,unfortunately,losing the opport... Gallbladder cancer(GBC)is a rare and lethal malignancy;however,it represents the most common type of biliary tract cancer.Patients with GBC are often diagnosed at an advanced stage,thus,unfortunately,losing the opportunity for curative surgical intervention.This situation leads to lower quality of life and higher mortality rates.In recent years,the rapid development of endoscopic equipment and techniques has provided new avenues and possibilities for the early and minimally invasive diagnosis and treatment of GBC.This editorial comments on the article by Pavlidis et al.Building upon their work,we explore the new needs and corresponding models for managing GBC from the endoscopic diagnosis and treatment perspective. 展开更多
关键词 ENDOSCOPY Diagnosis and treatment Gallbladder carcinoma Minimal invasive new need new model
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A new diatom genus Spargeria gen.nov.(Bacillariophyceae)from Xizang,China,and the description of two new species
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作者 Yan LIU John Patrick KOCIOLEK +5 位作者 Li WANG Xinxin LU Huan ZHU Guoxiang LIU Fengyang SUI Yawen FAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期291-303,共13页
During our investigation of diatom biodiversity in Xizang,two species exhibited unique morphological features discriminative from all previously known genera.Herein we describe these two species and describe as new th... During our investigation of diatom biodiversity in Xizang,two species exhibited unique morphological features discriminative from all previously known genera.Herein we describe these two species and describe as new the genus,Spargeria gen.nov.The new genus features narrow to wide rectangular valves,narrow valve mantles,filiform raphe branches that occur on the valve face only,terminal raphe fissures straight or slightly deflected to same side,bow-tie shaped central areas,chambered striae present on the valve face only,being absent from the mantle,wider striae near the axial area and very narrow near the margin,multiseriate striae with small and round areolae that are occluded externally.Comparatively,Spargeria zhuii sp.nov.has larger and robust valves,radiate striae,with one divergent stria near the apices,while Spargeria chenia sp.nov.is smaller,with narrow valves,striae slightly radiate in the middle,becoming convergent or parallel near apices.This new genus belongs to the family Pinnulariaceae,and it was compared and contrasted with other genera of this family.Our work suggests the need for continued studies to document the biodiversity of diatoms in Xizang. 展开更多
关键词 Spargeria new genus Pinnulariaceae morphology Xizang
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Lineaperpetua gen.nov.:a new diatom genus in the Thalassiosirales supported by morphology and molecular data
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作者 Pan YU Lin YANG +4 位作者 Qingmin YOU John Patrick KOCIOLEK Kangyu WANG Yonghong BI Quanxi WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期277-290,共14页
Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of... Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of genus include:a tangentially undulated valve face;continuous cribra areolae on the valve interior consisting of pores arranged as strips;single rimoportula located inside the ring of marginal fultoportulae.Additionally,phylogenetic analysis based on nuclear small subunit(SSU)rDNA sequences and nuclear large subunit(LSU)rDNA gene placed the three strains of L.lacustris in a single,monophyletic clade at a considerable sequence distance from the other genera(Thalassiosira,Conticribra,Planktoniella,Shinodiscus,and other genera)belonging to Thalassiosirales.Despite the similarities with some species of Thalassiosira,Conticribra,and Spicaticribra,the suite of features found in Lineaperpetua differentiate it from these other genera.These molecular data and morphological characters suggest an affinity of the new genus to the Thalassiosiraceae. 展开更多
关键词 DIATOM MORPHOLOGY new genus PHYLOGENY TAXONOMY Thalassiosiraceae
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Extraction of Acoustic Normal Mode Depth Functions Using Range-Difference Method with Vertical Linear Array Data
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作者 GAO Siyu LI Weilu +2 位作者 ZHANG Yinquan LI Xiaolei WANG Ning 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期871-882,共12页
Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when t... Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when two or more singular values obtained from the cross-spectral density matrix diagonalization are nearly equal,this results in unsatisfactory extraction outcomes for the normal mode depth functions.To address this issue,we introduced in this paper a range-difference singular value decomposition method for the extraction of normal mode depth functions.We performed the mode extraction by conducting singular value decomposition on the individual frequency components of the signal's cross-spectral density matrix.This was achieved by using pressure and its range-difference matrices constructed from vertical line array data.The proposed method was validated using simulated data.In addition,modes were successfully extracted from ambient noise. 展开更多
关键词 range difference depth function extraction normal mode
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NORMALIZED SOLUTIONS FOR THE GENERAL KIRCHHOFF TYPE EQUATIONS
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作者 Wenmin LIU Xuexiu ZHONG Jinfang ZHOU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1886-1902,共17页
In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constrain... In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constraint f_(R)^N u^2dx=c,where M∈C([0,∞))is a given function satisfying some suitable assumptions.Our argument is not by the classical variational method,but by a global branch approach developed by Jeanjean et al.[J Math Pures Appl,2024,183:44–75]and a direct correspondence,so we can handle in a unified way the nonlinearities g(s),which are either mass subcritical,mass critical or mass supercritical. 展开更多
关键词 normalized solution Kirchhoff type equations general nonlinearities asymptotic behavior
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A new infrageneric classification of Gastrochilus(Orchidaceae:Epidendroideae)based on molecular and morphological data
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作者 Jun-Yi Zhang Yue-Hong Cheng +5 位作者 Min Liao Yu Feng Sen-Long Jin Ting-Mei He Hai He Bo Xu 《Plant Diversity》 SCIE CAS CSCD 2024年第4期435-447,共13页
Gastrochilus is an orchid genus containing 73 species of mainly epiphytic on trees or rocks in mountain forests of tropical and subtropical Asia.Previous phylogenetic analyses and morphological assessments have failed... Gastrochilus is an orchid genus containing 73 species of mainly epiphytic on trees or rocks in mountain forests of tropical and subtropical Asia.Previous phylogenetic analyses and morphological assessments have failed to produce a well-resolved phylogeny at the infrageneric level.In the present study,a new infrageneric classification of Gastrochilus is proposed based on thoroughly morphological and phylogenetic analyses based on 52 species.Our phylogenetic analysis divided the genus into six sections including three new sections,G.sect.Pseudodistichi,G.sect.Brachycaules and G.sect.Acinacifolii.We also reinstate G.suavis to the specific rank.Furthermore,two new species,G.armeniacus Jun Y.Zhang,B.Xu&Yue H.Cheng and G.minjiangensis Jun Y.Zhang,B.Xu&Yue H.Cheng,are described and illustrated.A key to six sections of the genus is presented. 展开更多
关键词 Gastrochilus PHYLOGENY Character evolution TAXONOMY new species
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Taxonomy of Two New Peritrich Ciliates(Protozoa:Ciliophora)from Inland Saltwaters of China
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作者 YU Ying ZHANG Yong +2 位作者 LIANG Ziyao LI Jiqiu LIN Xiaofeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期811-821,共11页
The inland saltwater lakes harbor exceptional biodiversity.Here,two new species of solitary sessile peritrich ciliates were isolated from Qinghai Lake,the largest inland saltwater lake in China.Their morphology,ciliat... The inland saltwater lakes harbor exceptional biodiversity.Here,two new species of solitary sessile peritrich ciliates were isolated from Qinghai Lake,the largest inland saltwater lake in China.Their morphology,ciliature,silverline system,and molecular phylogeny were investigated based on live observation,silver staining,and analysis of the small subunit ribosomal DNA(SSU rDNA).Vorticella paraglobosa sp.n.is characterized mainly by its obconical or elongate bell-shaped zooid,C-shaped macronucleus,single ventrally located contractile vacuole,two-rowed infundibular polykinety 3,and 28-38 silverlines between peristome and aboral tro-chal band and 10-15 between aboral trochal band and scopula.Vorticella cotyliformis sp.n.differs from its congeners mainly by its double-layered peristomial lip,cup-shaped zooid,J-shaped macronucleus,single ventrally positioned contractile vacuole,three-rowed infundibular polykinety 3,and 70-85 silverlines between peristome and aboral trochal band and 21-25 between aboral trochal band and scopula.The SSU rDNA sequences of the two new species were obtained,and the subsequent molecular phylogenetic analysis supported their taxonomic classification. 展开更多
关键词 molecular phylogeny morphology new species Qinghai Lake TAXONOMY
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Schur Forms and Normal-Nilpotent Decompositions
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作者 LI Zhen 《应用数学和力学》 CSCD 北大核心 2024年第9期1200-1211,共12页
Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,su... Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,such as the triple decomposition of motion(TDM)and normal-nilpotent decomposition(NND),have been proposed to analyze the local motions of fluid elements.However,due to the existence of different types and non-uniqueness of Schur forms,as well as various possible definitions of NNDs,confusion has spread widely and is harming the research.This work aims to clean up this confusion.To this end,the complex and real Schur forms are derived constructively from the very basics,with special consideration for their non-uniqueness.Conditions of uniqueness are proposed.After a general discussion of normality and nilpotency,a complex NND and several real NNDs as well as normal-nonnormal decompositions are constructed,with a brief comparison of complex and real decompositions.Based on that,several confusing points are clarified,such as the distinction between NND and TDM,and the intrinsic gap between complex and real NNDs.Besides,the author proposes to extend the real block Schur form and its corresponding NNDs for the complex eigenvalue case to the real eigenvalue case.But their justification is left to further investigations. 展开更多
关键词 Schur form normal matrix nilpotent matrix tensor decomposition vortex identification
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NORMALITY AND THE NUMBER OF ZEROS
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作者 WANG Guang-sheng WEI Dong-mei XU Yan 《数学杂志》 2024年第5期377-382,共6页
In this paper,we study normal families of meromorphic functions.By using the idea in[11],we obtain some normality criteria for families of meromorphic functions that concern the number of zeros of the differential pol... In this paper,we study normal families of meromorphic functions.By using the idea in[11],we obtain some normality criteria for families of meromorphic functions that concern the number of zeros of the differential polynomial,which extends the related result of Li,and Chen et al..An example is given to show that the hypothesis on the zeros of a(z)is necessary. 展开更多
关键词 Meromorphic function normal family differential polynomial ZERO
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Yuzaoea gen. nov., a new biraphid diatom(Bacillariophyceae)genus and its phylogenetic significance
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作者 Honghan Liu Chenhong Li +6 位作者 Lang Li Xuesong Li Lin Sun Junrong Liang Jun Zhang Yahui Gao Changping Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期130-136,共7页
The flexed frustules in pennate diatoms are usually associated with monoraphid diatoms. Interestingly, we found a biraphid diatom species with flexed frustules in an offshore intertidal beach environment on Weizhou Is... The flexed frustules in pennate diatoms are usually associated with monoraphid diatoms. Interestingly, we found a biraphid diatom species with flexed frustules in an offshore intertidal beach environment on Weizhou Island,Beihai City, Guangxi Zhuang Autonomous Region, China. Therefore, based on morphological characteristics, we described a new genus of diatoms Yuzaoea sinensis gen. et sp. nov. CH Li, HH Liu, YH Gao & CP Chen. The frustule of this genus is characterized by heterogeneous frustule with one concave valve and one convex valve,complete raphe on both valves, straight and moderately eccentric raphe, uniseriate striae and girdle bands with a single row of areolae. The most identifying feature of this genus was the flexed frustule, which is rare in biraphid diatoms and common in monoraphid diatoms. We compared the morphometric characteristics of genus Yuzaoea with genus Rhoikoneis and several genera within the family Rhoicospheniaceae, including Rhoicosphenia,Campylopyxis, and Cuneolus. Phylogenetic analyses based on SSU rRNA and rbc L showed that the genus Yuzaoea was the sister group to the clade of Rhoicosphenia with a high support value(bootstrap values = 100%), and the clade “Yuzaoea+Rhoicosphenia” was sister to the clade of monoraphid diatoms, in which the genera Achnanthidium, Planothidium and some Cocconeis with high support values(bootstrap = 100%).Morphologically, the genus Yuzaoea shares many morphological features with monoraphid diatoms like genera Achnanthidium and Planothidium and the members within the Rhoicospheniaceae. Therefore, based on a combined morphological studies and phylogenetic results we suggested that this branch may represented the evolution of one kind monoraphid diatoms, from biraphid diatoms(e.g. genus Yuzaoea), to incompleted biraphid diatoms(e.g. genera Rhoicosphenia, Campylopyxis), to monoraphid diatoms(e.g. genera Achnanthidium and Planothidium). 展开更多
关键词 biraphid diatom marine new genus Rhoicospheniaceae TAXONOMY Yuzaoea
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Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions
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作者 ZHU Qiang YIN Qian +9 位作者 TAO Zhi-gang HE Man-chao ZHENG Bo-wen JING Hong-wen REN Shu-lin ZHANG Qiang MENG Bo BAI Dong-feng WU Sai-sai WU Jiang-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2393-2410,共18页
A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating... A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating geological disasters.This study conducted shear experiments on rough rock joints under displacement-controlled dynamic normal loads,investigating the shear behaviors of joints across varying initial normal loads,normal loading frequencies,and normal loading amplitudes.Experimental results showed that the peak/valley shear force values increased with initial normal loads and normal loading frequencies but showed an initial increase followed by a decrease with normal loading amplitudes.Dynamic normal loading can either increase or decrease shear strength,while this study demonstrates that higher frequencies lead to enhanced friction.Increased initial normal loading and normal loading frequency result in a gradual decrease in joint roughness coefficient(JRC)values of joint surfaces after shearing.Positive correlations existed between frictional energy dissipation and peak shear forces,while post-shear joint surface roughness exhibited a negative correlation with peak shear forces through linear regression analysis.This study contributes to a better understanding of the sliding responses and shear mechanical characteristics of rock joints under dynamic disturbances. 展开更多
关键词 dynamic normal displacement shear strength variations phase lag phenomenon STICK-SLIP
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