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New aspects of a small GTPase RAB35 in brain development and function
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作者 Ikuko Maejima Ken Sato 《Neural Regeneration Research》 SCIE CAS 2025年第7期1971-1980,共10页
In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting t... In eukaryotic cells,organelles in the secretory,lysosomal,and endocytic pathways actively exchange biological materials with each other through intracellular membrane trafficking,which is the process of transporting the cargo of proteins,lipids,and other molecules to appropriate compartments via transport vesicles or intermediates.These processes are strictly regulated by various small GTPases such as the RAS-like in rat brain(RAB)protein family,which is the largest subfamily of the RAS superfamily.Dysfunction of membrane trafficking affects tissue homeostasis and leads to a wide range of diseases,including neurological disorders and neurodegenerative diseases.Therefore,it is important to understand the physiological and pathological roles of RAB proteins in brain function.RAB35,a member of the RAB family,is an evolutionarily conserved protein in metazoans.A wide range of studies using cultured mammalian cells and model organisms have revealed that RAB35 mediates various processes such as cytokinesis,endocytic recycling,actin bundling,and cell migration.RAB35 is also involved in neurite outgrowth and turnover of synaptic vesicles.We generated brain-specific Rab35 knockout mice to study the physiological roles of RAB35 in brain development and function.These mice exhibited defects in anxiety-related behaviors and spatial memory.Strikingly,RAB35 is required for the precise positioning of pyramidal neurons during hippocampal development,and thereby for normal hippocampal lamination.In contrast,layer formation in the cerebral cortex occurred superficially,even in the absence of RAB35,suggesting a predominant role for RAB35 in hippocampal development rather than in cerebral cortex development.Recent studies have suggested an association between RAB35 and neurodegenerative diseases,including Parkinson's disease and Alzheimer's disease.In this review,we provide an overview of the current understanding of subcellular functions of RAB35.We also provide insights into the physiological role of RAB35 in mammalian brain development and function,and discuss the involvement of RAB35 dysfunction in neurodegenerative diseases. 展开更多
关键词 ENDOCYTOSIS ENDOSOMES hippocampal development neurodegenerative diseases RAB35
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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins
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作者 Daiyu Hu Yuanqing Cao +6 位作者 Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong Lai Zhengliang Gao 《Neural Regeneration Research》 SCIE CAS 2025年第1期242-252,共11页
Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-li... Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies. 展开更多
关键词 cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells NEUROGENESIS NEUROTOXICOLOGY ORGANOIDS stem cells
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Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development
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作者 Baoqi Hu Rui Wang +8 位作者 Hanyue Zhang Xiou Wang Sijia Zhou Bo Ma Yan Luan Xin Wang Xinlin Chen Zhichao Zhang Qianyan Kang 《Neural Regeneration Research》 SCIE CAS 2025年第3期900-912,共13页
The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and contin... The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation. 展开更多
关键词 bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells
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A Review of Research on Development of Interlanguage Pragmatic Competence from a Cognitive Perspective
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作者 王柯芦 《海外英语》 2014年第1X期209-212,共4页
English language learners' pragmatic competence is related to their success incross-cultural communication. Cognitive approaches, mainly the Noticing Hypothesis and Analysis/Control Model, have provided some insig... English language learners' pragmatic competence is related to their success incross-cultural communication. Cognitive approaches, mainly the Noticing Hypothesis and Analysis/Control Model, have provided some insights into the question of how to effectively develop second language(L2) learners' pragmatic competence. Empirical studies based on cognitive theoretical constructs suggest that pragmatic activitiesthat draw learners' attention and help them control attention to relevant and appropriate information and integrate those forms in real time of communication contribute to the development of interlanguage pragmatic competence. 展开更多
关键词 INTERLANGUAGE PRAGMATIC competence COGNITIVE persp
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From Xu to the Development of L2 Interactional Competence: A Conversation Analytic Case Study 被引量:7
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作者 Mei YANG Xiaofei LU 《Chinese Journal of Applied Linguistics》 2021年第3期273-291,430,共20页
Dialogues are fundamentally driven by xu(C. Wang, 2016, 2017), a Chinese word meaning continuation that captures the process in which interlocutors participate in interaction through the actions of(utterance) completi... Dialogues are fundamentally driven by xu(C. Wang, 2016, 2017), a Chinese word meaning continuation that captures the process in which interlocutors participate in interaction through the actions of(utterance) completion,(content) extension, and(topic) creation(CEC). This article reports a conversation analytic case study designed to investigate how the continuation strategies of CEC are used in real-time communication to achieve mutual understanding, and thus to construct intersubjectivity(Verhagen, 2005) and promote the development of second language(L2)interactional competence. Our data consisted of audio and video recordings of a 25-minute conversation between two L2 English speakers, one expert and one novice, and a stimulated recall interview with them. Results revealed that the expert employed CEC at the early stage of interaction to maintain successful communication, and the novice gradually aligned with the expert and used CEC to achieve mutual understanding, construct intersubjectivity, and create opportunities for interaction and learning at the late stage, displaying her development of L2 interactional competence. Our findings have useful implications for theoretical and methodological development of the xu-argument studies as well as for xu-based L2 pedagogy. 展开更多
关键词 the xu-argument INTERSUBJECTIVITY interactional competence continuation strategies conversation analysis
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Intercultural Competence Development of Chinese Students After a Short-Term Study Abroad Experience 被引量:1
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作者 Shuangmei Gao Teresa J. Kennedy 《Sino-US English Teaching》 2019年第5期177-196,共20页
This study investigated Chinese students’ intercultural competence and linguistic growth during a six-week study abroad program. The students and their professor participated in pre- and post-tests covering written a... This study investigated Chinese students’ intercultural competence and linguistic growth during a six-week study abroad program. The students and their professor participated in pre- and post-tests covering written and oral language competency as well as intercultural competence. The Global Scale of English assessed student language development to determine linguistic growth and the Assessment of Intercultural Competence of Chinese College Students (AIC-CCS) was used to determine student growth of intercultural competence skills, specifically related to cultural knowledge, skills, attitudes, and awareness as a result of their experiences in a non-Western context. Results indicated that students experienced a change in the salience of intercultural knowledge themes over their period abroad, as well as improved their individual language abilities. This study provides suggestions for future programming focused on the development of Chinese student intercultural competencies during short-term study abroad experiences in Western university environments. 展开更多
关键词 ENGLISH LANGUAGE development linguistic growth Global Scale of ENGLISH second LANGUAGE (L2) INTERCULTURAL COMMUNICATIVE competence (ICC) CHINESE college students CHINESE context
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Effectiveness of experiential teaching method on the development of nursing students’skill competence:a systematic review and meta-analysis 被引量:2
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作者 Bo Zhang Qing-Yong Ma +4 位作者 Xiang-Shu Cui Qi-Gui Xiao Hong-Yan Jin Xue Chen Yi-Yan Chen 《Frontiers of Nursing》 CAS 2020年第4期359-368,共10页
Objective:Skill competence is essential for nursing students and experiential teaching method has become increasingly popular in China’s nursing education.To systematically evaluate the effects of experiential teachi... Objective:Skill competence is essential for nursing students and experiential teaching method has become increasingly popular in China’s nursing education.To systematically evaluate the effects of experiential teaching method on the development of nursing students’skill competence,and to provide evidence for nursing education.Methods:The China National Knowledge Infrastructure,VIP,Wanfang Data,PubMed,and Web of Science databases were searched from their inception until November 28,2019.We screened the studies according to inclusion and exclusion criteria,extracted the data,and assessed the quality.Then,a meta-analysis was conducted.Results:Totally 15 studies were included,and 1,633 nursing students were analyzed by Review Manager5.3 and Stata15.1 software.The results show that the experiential teaching method can significantly improve nursing students’nursing skills such as training(SMD=1.05,95%CI:0.95–1.16,P=0.000),learning interest(ES=0.93,95%CI:0.79–1.06),ability to analyze and solve problems(ES=0.75,95%CI:0.55–0.94),ability to judge and innovative thinking(ES=1.01,95%CI:0.77–1.25),abilities of understanding and perception(ES=0.59,95%CI:0.34–0.83),and teaching satisfaction(ES=1.26,95%CI:1.13–1.4).Conclusions:The results suggest that the experiential teaching method is more effective for the nursing students’skill competence than traditional teaching in China.However,due to the heterogeneity and bias risk,a large sample and high-quality studies are needed in future to confirm its effectiveness. 展开更多
关键词 experiential teaching method nursing education META-ANALYSIS nursing students skill competence randomized controlled trial
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A Study of the Main Obstacles to the Development of Advanced Lexical Competence
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作者 邝斯琪 《Sino-US English Teaching》 2007年第3期11-17,共7页
The present study is to explore the main obstacles to the development of lexical competence in advanced English study. It is conducted by having questionnaires and interviews among 220 students and by analyzing the te... The present study is to explore the main obstacles to the development of lexical competence in advanced English study. It is conducted by having questionnaires and interviews among 220 students and by analyzing the teaching materials. The findings to the study indicate that the main obstacles are caused from the following aspects: neglecting the importance of developing vocabulary in the advanced study; neglecting activating the students' directing sense and detecting sense to difficult words; low rate of word recurrence in the teaching materials; requiring distinguishing the shade of the difference between synonyms excessively and too meticulously; overemphasizing the "negative transfer" of mother tongue; and some other obstacles to the development of lexical competence. 展开更多
关键词 advanced lexical competence word recurrence mentality resource
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Development and psychometric evaluation of the radiographers’ competence scale 被引量:1
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作者 Bodil TAndersson Lennart Christensson +1 位作者 Bengt Fridlund Anders Brostrom 《Open Journal of Nursing》 2012年第2期85-96,共12页
Assessing the competence of registered radiographers’ clinical work is of great importance because of the recent change in nursing focus and rapid technological development. Self-assessment assists radiographers to v... Assessing the competence of registered radiographers’ clinical work is of great importance because of the recent change in nursing focus and rapid technological development. Self-assessment assists radiographers to validate and improve clinical practice by identifying their strengths as well as areas that may need to be developed. The aim of the study was to develop and psychometrically test a specially designed instrument, the Radiographers Competence Scale (RCS). A cross sectional survey was conducted comprising 406 randomly selected radiographers all over Sweden. The study consisted of two phases;the development of the instrument and evaluation of its psychometric properties. The first phase included three steps: 1) construction of the RCS;2) pilot testing of face and content validity;and 3) creation of a web-based 54-item questionnaire for testing the instrument. The second phase comprised psychometric evaluation of construct validity, internal consistency reliability and item reduction. The analysis reduced the initial 54 items of the RCS to 28 items. A logical two-factor solution was identified explaining 53.8% of the total variance. The first factor labelled “Nurse initiated care” explained 31.7% of the total variance. Factor 2 labelled “Technical and radiographic processes” explained 22.1% of the total variance. The scale had good internal consistency reliability, with a Cronbach’s alpha of 0.87. The RCS is a short, easy to administer scale for capturing radiographers’ competence levels and the frequency of using their competence. The scale was found to be valid and reliable. The self-assessment RCS can be used in management, patient safety and quality improvement to enhance the radiographic process. 展开更多
关键词 competence Scale Instrument development Management NURSING Psychometric Evaluation RADIOGRAPHER RCS
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Chinese High School Students' Global Competence: Development and Assessment 被引量:3
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作者 Yan Yue Fai Man Chan +1 位作者 Xinyu Xu Yunyang Wu 《教育技术与创新》 2023年第1期16-26,共11页
With the advancement of globalization and digital technology,students'ability to live in an interconnected world has become increasingly important.Global competence has gradually become an important indicator for ... With the advancement of globalization and digital technology,students'ability to live in an interconnected world has become increasingly important.Global competence has gradually become an important indicator for assessing students'progress.In the study of global competence,Western countries took the lead,followed by China.China has gradually transitioned from learning from the ideas of other countries to the construction of global competence education with Chinese characteristics,demonstrating a catch-up trend.So,based on the PISA Global Competence Framework,this paper aims to interpret what global competence is,how to develop students'global competence in the context of Chinese school practices,and how to assess students'global competence using the PISA 2018 Global Competence Framework.As a result,it can substantially improve global competency research and development. 展开更多
关键词 HAS GLOBAL competence
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Anethole improves the developmental competence of porcine embryos by reducing oxidative stress via the sonic hedgehog signaling pathway 被引量:1
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作者 Ye Eun Joo Pil-Soo Jeong +8 位作者 Sanghoon Lee Se-Been Jeon Min-Ah Gwon Min Ju Kim Hyo-Gu Kang Bong-Seok Song Sun-Uk Kim Seong-Keun Cho Bo-Woong Sim 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1395-1407,共13页
Background Anethole(AN)is an organic antioxidant compound with a benzene ring and is expected to have a positive impact on early embryogenesis in mammals.However,no study has examined the effect of AN on porcine embry... Background Anethole(AN)is an organic antioxidant compound with a benzene ring and is expected to have a positive impact on early embryogenesis in mammals.However,no study has examined the effect of AN on porcine embryonic development.Therefore,we investigated the effect of AN on the development of porcine embryos and the underlying mechanism.Results We cultured porcine in vitro-fertilized embryos in medium with AN(0,0.3,0.5,and 1 mg/mL)for 6 d.AN at 0.5 mg/mL significantly increased the blastocyst formation rate,trophectoderm cell number,and cellular survival rate compared to the control.AN-supplemented embryos exhibited significantly lower reactive oxygen species levels and higher glutathione levels than the control.Moreover,AN significantly improved the quantity of mitochondria and mitochondrial membrane potential,and increased the lipid droplet,fatty acid,and ATP levels.Interestingly,the levels of proteins and genes related to the sonic hedgehog(SHH)signaling pathway were significantly increased by AN.Conclusions These results revealed that AN improved the developmental competence of porcine preimplantation embryos by activating SHH signaling against oxidative stress and could be used for large-scale production of high-quality porcine embryos. 展开更多
关键词 ANETHOLE Lipid metabolism Mitochondrial function Porcine embryo development Sonic hedgehog signaling pathway
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Discourse Competence Development in English Language Teaching: An Analysis of Media Text Discourse
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作者 王蕊 《海外英语》 2016年第21期237-238,共2页
This paper aims at exploring how the learners' discourse competence could be fully developed in second language acquisition facilitated by teachers through analysis of a piece of written discourse.
关键词 discourse competence social context analysis of discourse coherence and cohesion
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Effects of Transport,Storage Temperature and Time on Parthenogenetically Developmental Competence of Sheep Oocyte
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作者 Qiao Limin Qiao Fuqiang +5 位作者 Guo Tong Yao Hua Zhang Jinghe Xiao Xishan Hou Yinxu Guan Weijun 《Animal Husbandry and Feed Science》 CAS 2014年第3期138-140,共3页
This study was to investigate the effects of transport, storage temperature and time on parthenogenetical developmental competence of sheep oocyte. The ovaries were collected and randomly immersed in physiological sal... This study was to investigate the effects of transport, storage temperature and time on parthenogenetical developmental competence of sheep oocyte. The ovaries were collected and randomly immersed in physiological saline at ( 10 - 15 ) ℃, (20 - 25 ) ℃ and (30 - 35 ) ℃ and transported to the laboratory for culture. They were divided into three groups randomly in an optimized transport temperature, kept in physiological saline at4 ℃, (14 -18) ℃ and (25 -30) ℃ respectively; 15 - 17 h later, the ovaries were cutured for the maturation and parthenogenetic activation of oocytes. The results showed that the optimal transport temperature of ovaries was 20 -25 ℃, when the maturation rate and blastocysts rate reached 67.44% and 35.93% respectively. Incubating sheep ovaries at ( 14 - 18 ) ℃ for (15 -17) h did not reduce the maturation rate (61.81%) and blastocysts rate (29.03%) of oocyte significantly. However, incubating sheep ovaries at 4 ℃ or (25 -30) ℃ significantly reduced the maturation rate (41.90%, 18.40% ) and cleavage rate (9.09%, 13.04% ), and the ovaries could not develop into blastocysts at these two temperature ranges. It can be concluded that the optimal transport temperature of the sheep ovaries is 20 - 25 ℃, and incubation at 14 - 18 ℃ overnight in vivo does not affect the developmental competence of oocytes. 展开更多
关键词 Sheep ovary Storage temperature Transport temperature Oocytc developmental competence
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Development and Validation of an Instrument for Assessing Perceived Competences in Didactic Activity
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作者 Alina Costea Florinda Golu 《Psychology Research》 2018年第12期577-586,共10页
In the context of teacher competences’association with student performance,assessment of didactic competences is an important concern for educational professionals.The current study aims to develop and validate a too... In the context of teacher competences’association with student performance,assessment of didactic competences is an important concern for educational professionals.The current study aims to develop and validate a tool for assessing perceived competences in didactic activity for a group of Romanian teachers.The study examined 160 teachers from 15 schools in Bucharest,Romania,aged 20-60 years old.In the process of development and validation of the instrument(Assessment of perceived competences in didactic activity),the recommended steps were followed.Exploratory factorial analysis indicated the existence of three factors:effective communication of the teacher,development of students’critical thinking,and use of auxiliary resources.Reliability analysis showed high reliability coefficients,indicating good psychometric qualities of the scale.The correlations between the three factors were high,so the scale has acceptable convergent validity.Confirmatory factor analysis showed that the three factor model has indicators of good fit,also indicating good psychometric properties.The main practical implication is that the proposed instrument can be successfully used in identifying development needs of teachers resulting from the evaluation process.Based on the results derived from self-assessment of teaching competencies,customized professional development programs can be created for each teacher,aiming at developing skills and,implicitly,improving performance at the workplace. 展开更多
关键词 PERCEIVED competences in didactic ACTIVITY effective communication development of students’critical THINKING use of AUXILIARY RESOURCES
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The Development of Communicative Competence in the Classroom of College English
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作者 殷昭芹 《宁夏大学学报(人文社会科学版)》 2003年第3期123-125,共3页
关键词 交际能力 大学 英语教学 课堂教学 教师素质
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Historical Tracing of the Development of the Concepts of "Competence" and "Performance"
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作者 ZENG Jian-guo 《Sino-US English Teaching》 2007年第4期44-49,共6页
Competence and performance is an important pair of concepts in linguistics. Ever since their originality, they have aroused sufficient attention of the linguists. Many linguists have contributed a lot in their attempt... Competence and performance is an important pair of concepts in linguistics. Ever since their originality, they have aroused sufficient attention of the linguists. Many linguists have contributed a lot in their attempt to illustrate the concepts and clarification of them. A proper understanding of them can help the readers to gain more insight into the linguistics. What the linguist, Chomsky, originally meant by using competence and performance is somewhat different from what the current linguists mean by using them. The distance and distinction between competence and performance meant by Chomsky is also different from that meant by current linguists. That's to say there is some development of competence and performance since they were put forward. The shift is a gradual one, yet a very significant one. It reflects the linguists' effort to try to describe and categorize language learners' ability and their attempt to make use of them and measure them. This process actually narrows the distance and gap not only between theory and practice, but also between competence and performance. And at the same time, it reflects the linguists' frustration and confusion caused by the abstraction and complexity of them. By consulting the literature, the paper tries to follow their development step by step. The paper also points out some assumptions used by linguists when applying competence and performance. At the end of paper, it points out some implications to language teaching, which is important to language teachers and learners. 展开更多
关键词 competence and performance development RELATIONSHIP IMPLICATION
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GAMYB transcription factor LoMYB65 from lily plays a vital role in pollen development 被引量:2
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作者 Xinyue Liu Ling He +1 位作者 Ze Wu Nianjun Teng 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期223-238,共16页
Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination problems.There are many studies on pollen development in model plants,but few on flower crops such as lili... Lily(Lilium spp.)is an important horticultural crop,but its use is limited due to serious pollen contamination problems.There are many studies on pollen development in model plants,but few on flower crops such as lilies.Gibberellin(GA)is a large class of hormones and plays an important role in plant vegetative growth and reproductive development.GAMYB is a group of the R2R3-MYB family upregulated by gibberellin,and plays an important role in anther development.Here,we isolated a novel GAMYB,named LoMYB65,from lily,which was closely related to the AtMYB65 and AtMYB33 in Arabidopsis.Fluorescence quantitative PCR results showed that LoMYB65 was mainly expressed in lily anthers.LoMYB65 could be activated by 288μmol·L^(-1)GA3treatment and the LoMYB65 protein was located in the nucleus and cytoplasm,and had transactivation in yeast and tobacco leaf cells.The conserved motif within 226 amino acids of the C-terminal of LoMYB65 contributed to its transactivation.Overexpression of LoMYB65 caused dwarf phenotype,unnormal tapetum development,less seeds of siliques in transgenic Arabidopsis plants,the transgenic plants showed partly male sterile.Simultaneously,silencing of LoMYB65 with VIGS(Virus Induced Gene Silencing)in lily anthers caused unnormal pollen development and reduced the pollen amount.Overexpression of LoMYB65 in Arabidopsis and silencing of LoMYB65 in lily resulted in decreased pollen counts,so we speculate that LoMYB65 may be dose-dependent.Overall,these findings suggest that LoMYB65 may play an important role in anther development and pollen formation in lily.LoMYB65 may provide a useful candidate gene for pollenless breeding of lily. 展开更多
关键词 LILY Anther development Pollen pollution GAMYB VIGS
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Developmental competence and ultrastructural changes of heat-stressed mouse early blastocysts produced in vitro
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作者 Pingping Qu Wenru TIAN Tao LI Zhongling JIANG Shansong GAO Zhongjie TIAN Mingzhi WANG 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第1期61-66,共6页
Mouse early blastocysts were exposed to temperatures of 39℃ and 41℃ for 2 h, respectively, to determine their developmental competence and ultrastructural changes. The results showed that heat stress at 41 ℃ for 2 ... Mouse early blastocysts were exposed to temperatures of 39℃ and 41℃ for 2 h, respectively, to determine their developmental competence and ultrastructural changes. The results showed that heat stress at 41 ℃ for 2 h, significantly reduced the percentages of expanded and hatched blastocysts, but not at 39℃ for 2 h. The average cell numbers in expanded blastocysts, which developed from early blastoeysts heat-stressed at temperatures of 39℃ and 41 ℃, were significantly reduced. The average cell numbers in hatched blastocysts subjected to heat stress were no different from those in the control group cultured at 37 ℃ . The mitochondria of the early blastocysts heat-stressed at 39℃ for 2 h, were slightly swollen, but they had recovered after culturing at 37 ℃ for 2 h. However, the mitochondria in the blastocysts heat stressed at 41 ℃ for 2 h were severely swollen, and their number increased. The ribosomes shed from the rough endoplasmic reticulum, and the number of secondary lysosomes in the plasma increased. The integrity of desmosomes was disrupted. The space between the nuclear envelope and the perivitelline membrane enlarged. The fibre fraction and the particulate fraction of nueleoli were separated. The heterochromatin in nueleoli was also increased in its quantity. There were some lamellar-shape structures and heterogeneous dense materials exhibiting in the cytoplasm. The ultrastructural changes induced by heat shock at 41 ℃ for 2 h were not reversible. In conclusion, the damage of heat stress to mitoehondria, lysosomes, ribosomes and cell nucleus, may be one of the most important factors that inhibit the normal development of mouse early blastoeysts . 展开更多
关键词 Heat tress MOUSE Early blastocysts developmental competence ULTRASTRUCTURE
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Instruction of the Multi-dimensional Developing Perspective on Translation in Translation Competence Development
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作者 ZOU Yanqun 《Sino-US English Teaching》 2022年第5期159-166,共8页
The overlook of the cultivation of learners’perspective on translation is one of the essential reasons that we fail to enhance learners’translation competence effectively and efficiently.The perspective on translati... The overlook of the cultivation of learners’perspective on translation is one of the essential reasons that we fail to enhance learners’translation competence effectively and efficiently.The perspective on translation mirrors not only the interpretation of the essence,value,and function of translation,but the interpretation of culture and intercultural communication,which offers inspiration and implication on translation in the current context.This study analyzes the significance of the multi-dimensional developing perspective on translation and elaborates on the HBARP model to integrate the perspective on translation throughout the learning and teaching process to inspire learners to interpret translation essence and features,to highlight the intercultural communicative significance in the current context with a historical vision. 展开更多
关键词 multi-dimensional developing perspective on translation significance and instruction translation competence development
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Alteration of ERβ gene Rsal polymorphism may contribute to reduced fertilization rate and embryonic developmental competence
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作者 Qiu-Fang Zhang Huai-Liang Feng +4 位作者 Lan Zhao Ping Liu Li Li Jie Yan Jie Qiao 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第2期317-321,共5页
This paper aims to determine the possible role of estrogen receptor-β (ERβ) gene Rsal polymorphism on sperm fertility and early embryonic development in humans. Three groups of Chinese men were recruited: in vitr... This paper aims to determine the possible role of estrogen receptor-β (ERβ) gene Rsal polymorphism on sperm fertility and early embryonic development in humans. Three groups of Chinese men were recruited: in vitro fertilization (IVF) group, including 374 couples who underwent conventional IVF; intracytoplasmic sperm injection (ICSI) group, including 294 couples who underwent an ICSI procedure using ejaculated sperm; and azoospermic group, consisting of 197 couples who underwent ICSI using either testis or epididymis sperm. Rsal polymorphism in the ERβ gene was detected by polymerase chain reaction (PCR)-restriction fragment length polymorphism technique; fertilization and high-quality embryo rates were evaluated for each group. In each group, no significant differences were found in the overall rates of fertilization and high-quality embryos among GG, AG and AA genotypes. However, the proportion of cycles possessing a satisfactory high-quality embryo rate with the AA genotype was significantly lower than that in the wild-type GG genotype from each group. These results demonstrated that sperm possessing the ERβ RsalA genotype may have reduced fertilization ability and decreased early embryonic developmental potential, which could directly or indirectly contribute to the low fertilization rate and early embryonic developmental arrest in some cases. 展开更多
关键词 embryo development estrogen receptor-β gene FERTILIZATION intracytoplasmic sperm injection in vitro fertilization poly-morphism
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