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再论中产阶级:理论、历史与类型学 兼及一种全球化的视野 被引量:26
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作者 周晓虹 《社会》 北大核心 2005年第4期1-24,共24页
The emergence of the middle class was closely related to the appearance of industrial society and its consequential constant changes in the social structure. Karl Marx and other theorists in the same camp were among t... The emergence of the middle class was closely related to the appearance of industrial society and its consequential constant changes in the social structure. Karl Marx and other theorists in the same camp were among the earliest scholars who discussed that topic. For a quite long period of time, the debate was mainly focused on the characteristics of the “new middle class.” The middle class, however, has undergone a categorical transformation from the old to the new middle-class, and furthermore, this transformation itself has signified the transition in social patterns from industrial to post-industrial society as well as economic globalization, both of which have contributed to the growth and global expansion of the middle class, having thus fundamentally renovated the middle class. 展开更多
关键词 中产阶级 全球化 类型学 structure 历史 global from other among QUITE WHICH and CAMP that time this well both have The new HAS of to its in who For
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One-stitch anastomosis through the skin with bicanalicular intubation:a modified approach for repair of bicanalicular laceration 被引量:14
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作者 Hai Tao Peng Wang +3 位作者 Cui Han Jian Zhang Fang Bai Zhao-Yan He 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第5期656-658,共3页
AIM:To evaluate the efficacy and safety of one-stitch anastomosis through the skin with bicanalicular silicone tube intubation in repairing of bicanalicular laceration.METHODS:The clinical data of 15 consecutive patie... AIM:To evaluate the efficacy and safety of one-stitch anastomosis through the skin with bicanalicular silicone tube intubation in repairing of bicanalicular laceration.METHODS:The clinical data of 15 consecutive patients with both superior and inferior canalicular laceration in one eye who underwent surgical repair using one-stitch anastomosis through the skin and bicanalicular stent were retrospective studied.All the operations were performed under surgical microscope,5-0 silk sutures were used and were with bicanalicular silicone tube(diameter was 8mm) intubation,for one lacerated canaliculi one-stitch anastomosis through the skin.The stents were left in place for 3 months postoperatively and then removed.The follow-up period was 3-36 months(average 14 months). RESULTS:In 15 patients,13 patients were cured entirely,1 patient was meliorated,1 patient with no effects.All patients had got good recovery of eyelid laceration with no traumatic deformity in eyelid and canthus.Complication was seen in one case,for not followed the doctor’s guidance to come back to hospital to had the suture removed on the 7thday after operation,when he came at the 15thday,the inferior canalicular wall and eyelid skin were corroded by the suture caused 2mm wound,and the inside silicone tube was exposed,a promptly repair with 10-0 nylon suture was done,the wound healed in a week.There were no early tube protrusions and punctal slits in the patients.CONCLUSION:One-stitch anastomosis through the skin with bicanalicular silicone tube intubation is a good method in repair of bicanalicular laceration in one eye,the cut ends can be anastomosed directly,and with excellent cosmetic results,it is acceptable for the patients.For there is no suture remained in the wound permanently,so there is no suture-related granuloma which may cause obstruction or stenosis of canaliculi.It is simple,economical,effective and safe. 展开更多
关键词 both superior and inferior canalicular laceration REPAIR one-stitch anastomosis through the skin bicanalicular intubation
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换种方式说“艺术边界” 被引量:11
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作者 周宪 《北京大学学报(哲学社会科学版)》 CSSCI 北大核心 2016年第6期19-26,40,共9页
艺术边界的问题涉及如何区分艺术与非艺术,随着当代艺术的激进反叛,何为艺术边界变得越来越难以回答。从对艺术本质的讨论,到再现说、表现说和形式说,各种关于艺术本质及其边界条件的理论层出不穷。但是这些研究方法均带有某种非此即彼... 艺术边界的问题涉及如何区分艺术与非艺术,随着当代艺术的激进反叛,何为艺术边界变得越来越难以回答。从对艺术本质的讨论,到再现说、表现说和形式说,各种关于艺术本质及其边界条件的理论层出不穷。但是这些研究方法均带有某种非此即彼二元对立的思维范式,未能很好地解决艺术边界问题。中国传统哲学和美学对二元概念关系的独特处理方式,对于解决艺术边界难题提供了颇有启发性的思想资源。特别是中国传统哲学和美学中二元概念相互依存、相互包含和相互转化的原则,为解决艺术边界问题开辟了新的思路,有助于当代美学深化对艺术边界的讨论,并实现从非此即彼向兼而有之的范式转型。 展开更多
关键词 艺术边界 艺术与非艺术 二元对立 非此即彼 兼而有之
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Algebraic dynamics algorithm:Numerical comparison with Runge-Kutta algorithm and symplectic geometric algorithm 被引量:7
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作者 WANG ShunJin ZHANG Hua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第1期53-69,共17页
Based on the exact analytical solution of ordinary differential equations, a truncation of the Taylor series of the exact solution to the Nth order leads to the Nth order algebraic dynamics algorithm. A detailed numer... Based on the exact analytical solution of ordinary differential equations, a truncation of the Taylor series of the exact solution to the Nth order leads to the Nth order algebraic dynamics algorithm. A detailed numerical comparison is presented with Runge-Kutta algorithm and symplectic geometric algorithm for 12 test models. The results show that the algebraic dynamics algorithm can better preserve both geometrical and dynamical fidelity of a dynamical system at a controllable precision, and it can solve the problem of algorithm-induced dissipation for the Runge-Kutta algorithm and the problem of algorithm-induced phase shift for the symplectic geometric algorithm. 展开更多
关键词 algebraic dynamics ALGORITHM for ordinary differential equations preserving both geometrical and dynamical FIDELITY NUMERICAL COMPARISON with RUNGE-KUTTA ALGORITHM and SYMPLECTIC geometric ALGORITHM
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Failure mechanism and stability control technology of rock surrounding a roadway in complex stress conditions 被引量:8
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作者 Yu Yang Bai Jianbiao +3 位作者 Chen Ke Wang Xiangyu Xiao Tongqiang Chen Yong 《Mining Science and Technology》 EI CAS 2011年第3期301-306,共6页
To solve the problem of supporting three downhill coal structures in the Yongan Coal Mine of Shanxi Jincheng, we studied the regular development of stress and plastic zones and characteristics of deformation of rock s... To solve the problem of supporting three downhill coal structures in the Yongan Coal Mine of Shanxi Jincheng, we studied the regular development of stress and plastic zones and characteristics of deformation of rock surrounding roadway groups after a period of roadway driving, mining one side as well as mining both sides, we used FLAC 3D for our numerical and theoretical analyses. Field test were carried out, where we revealed the deformation mechanism of roadways and its coal pillars in complex stress conditions. We proposed a roadway stability control technology using backwall grouting with high-water rapid hardening material and combined support with bolt and cable anchoring after mining both sides. Our field practices showed that deformation of rock surrounding roadways can be controlled with this technology. 展开更多
关键词 both sides miningNumerical simulation FLAC3D Grouting reinforcementSupport parameters
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Automated Actuarial Data Analytics-Based Inflation Adjusted Frequency Severity Loss Reserving Model
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作者 Brighton Mahohoho 《Open Journal of Statistics》 2024年第3期341-393,共53页
In this paper, the Automated Actuarial Loss Reserving Model is developed and extended using machine learning. The traditional actuarial reserving techniques are no longer compatible with the increase in technological ... In this paper, the Automated Actuarial Loss Reserving Model is developed and extended using machine learning. The traditional actuarial reserving techniques are no longer compatible with the increase in technological advancement currently at hand. As a result, the development of the alternative Artificial Intelligence Based Automated Actuarial Loss Reserving Methodology which captures diverse risk profiles for various policyholders through augmenting the Micro Finance services, Auto Insurance Services and Both Services lines of business on the same platform through the computation of the Comprehensive Automated Actuarial Loss Reserves (CAALR) has been implemented in this paper. The introduction of the four further types of actuarial loss reserves to those existing in the actuarial literature seems to significantly reduce lapse rates, reduce the reinsurance costs as well as expenses and outgo. As a matter of consequence, this helps to bring together a combination of new and existing policyholders in the insurance company. The frequency severity models have been extended in this paper using ten machine learning algorithms which ultimately leads to the derivation of the proposed machine learning-based actuarial loss reserving model which remarkably performed well when compared to the traditional chain ladder actuarial reserving method using simulated data. 展开更多
关键词 Automated Actuarial Loss Reserves Artificial Intelligence Micro Finance Loss Reserving Auto Insurance Loss Reserving both Services Loss Reserving
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Gα_s signaling controls intramembranous ossification during cranial bone development by regulating both Hedgehog and Wnt/β-catenin signaling 被引量:7
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作者 Ruoshi Xu Sanjoy Kumar Khan +4 位作者 Taifeng Zhou Bo Gao Yaxing Zhou Xuedong Zhou Yingzi Yang 《Bone Research》 CAS CSCD 2018年第4期340-354,共15页
How osteoblast cells are induced is a central question for understanding skeletal formation. Abnormal osteoblast differentiation leads to a broad range of devastating craniofacial diseases. Here we have investigated i... How osteoblast cells are induced is a central question for understanding skeletal formation. Abnormal osteoblast differentiation leads to a broad range of devastating craniofacial diseases. Here we have investigated intramembranous ossification during cranial bone development in mouse models of skeletal genetic diseases that exhibit craniofacial bone defects. The GNAS gene encodes Gαs that transduces GPCR signaling. GNAS activation or loss-of-function mutations in humans cause fibrous dysplasia(FD) or progressive osseous heteroplasia(POH) that shows craniofacial hyperostosis or craniosynostosis, respectively. We find here that, while Hh ligand-dependent Hh signaling is essential for endochondral ossification, it is dispensable for intramembranous ossification, where Gαsregulates Hh signaling in a ligand-independent manner. We further show that Gαscontrols intramembranous ossification by regulating both Hh and Wnt/β-catenin signaling. In addition, Gαsactivation in the developing cranial bone leads to reduced ossification but increased cartilage presence due to reduced cartilage dissolution, not cell fate switch. Small molecule inhibitors of Hh and Wnt signaling can effectively ameliorate cranial bone phenotypes in mice caused by loss or gain of Gnas function mutations, respectively. Our work shows that studies of genetic diseases provide invaluable insights in both pathological bone defects and normal bone development, understanding both leads to better diagnosis and therapeutic treatment of bone diseases. 展开更多
关键词 s signaling controls intramembranous ossification during cranial bone development by regulating both Hedgehog and Wnt catenin signaling
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Characterization of Three Novel Wheat LThinopyrum intermedium Addition Lines with Novel Storage Protein Subunits and Resistance to Both Powdery Mildew and Stripe Rust 被引量:6
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作者 Yuhai Wang Honggang Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2016年第1期45-48,共4页
Wide hybridization is an effective approach for enhancing the resistance of bread wheat (Triticum aestivum L.) to biotic and abiotic stresses by introducing favorable alien genes (Sepsi et al., 2008). Wheatgrass, ... Wide hybridization is an effective approach for enhancing the resistance of bread wheat (Triticum aestivum L.) to biotic and abiotic stresses by introducing favorable alien genes (Sepsi et al., 2008). Wheatgrass, Thinopyrum intermedium (Host) Barkworth & D.R. Dewey or Agropyron intermedium (Host) Beauvoir (2n = 42; genome formula JJjSjSstst), is a perennial species in the tribe Triticeae and an important source of wheat improvement for biotic and abiotic stress resistance and quality-related traits, such as high grain protein concentration (Chen et al., 1998; 2001; 2003; Han et al., 2004; Li and Wang, 2009). In addition, the ready crossing ability of wheatgrass with various Triticum species has made it popular in germ- plasm development. 展开更多
关键词 Th Characterization of Three Novel Wheat LThinopyrum intermedium Addition Lines with Novel Storage Protein Subunits and Resistance to both Powdery Mildew and Stripe Rust GISH FISH
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BENEFITING FROM BOTH THE COMMUNICATIVE APPROACHES AND THE TRADITIONAL CHINESE METHODS IN ELT 被引量:5
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作者 Xu Ping Suzhou University,Jiangsu 《Chinese Journal of Applied Linguistics》 1999年第2期4-9,共6页
For some time,ELT in China has been undergoing a heated discussion as to the best way ofteaching.Some think that the communicative approaches is inappropriate while others think that the tra-ditional Chinese methods a... For some time,ELT in China has been undergoing a heated discussion as to the best way ofteaching.Some think that the communicative approaches is inappropriate while others think that the tra-ditional Chinese methods are too old-fashioned.From various points of view,this paper argues that boththe communicative approach and the traditional Chinese methods can co-exist and influence each other inthe present Chinese teaching context. 展开更多
关键词 BENEFITING FROM both THE COMMUNICATIVE APPROACHES AND THE TRADITIONAL CHINESE METHODS IN ELT
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Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite
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作者 Jeongho Yang Woongbeom Heogh +15 位作者 Hogi Ju Sukhyun Kang Tae-Sik Jang Hyun-Do Jung Mohammad Jahazi Seung Chul Han Seong Je Park Hyoung Seop Kim Susmita Bose Amit Bandyopadhyay Martin Byung-Guk Jun Young Won Kim Dae-kyeom Kim Rigoberto CAdvincula Clodualdo Aranas Jr Sang Hoon Kim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1239-1256,共18页
The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in orde... The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed fusion.This is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid composite.This study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive manufacturing.This strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid composite.Consequently,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional structure.This outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations. 展开更多
关键词 Laser powder bed fusion Mg_(2)Si-SiC/nitride hybrid composite both the thermal diffusion-and chemical reaction-based metallurgy Functionally graded structure Compositional gradient Wear resistance.
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Granulomatous lobular mastitis treated by a combined internal and external treatment of traditional Chinese medicine:A case report
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作者 Tian Meng Mei-Ling Chu +3 位作者 Bing Wang Mei-Na Ye Yi-Qin Cheng Hong-Feng Chen 《World Journal of Clinical Cases》 SCIE 2024年第21期4748-4754,共7页
BACKGROUND Granulomatous lobular mastitis(GLM)is a rare benign inflammatory disease of the breast and is classified under comedo mastitis in traditional Chinese medicine(TCM).The etiology of this disease is unknown,an... BACKGROUND Granulomatous lobular mastitis(GLM)is a rare benign inflammatory disease of the breast and is classified under comedo mastitis in traditional Chinese medicine(TCM).The etiology of this disease is unknown,and it mainly occurs in women of childbearing age.The diagnosis depends on histopathological biopsy.At present,there is no systematic and standardized treatment plan for GLM.In the absence of evidence supporting an infectious etiology,affected patients might continue to receive multiple courses of antibiotics and unnecessary surgery.CASE SUMMARY A 37-year-old Chinese woman with a history of coronavirus disease 2019 infection presented with swelling and pain in the left breast.She also had erythema,nodules in the lower extremities,arthritis in both knees,cough,and headache.In the early stage of GLM,the mass was not significantly reduced by conservative treatment with internal application of TCM;hence,surgical treatment was carried out.The aim of postoperative treatment was to drain the pus,eliminate the necrosed tissue,and expand the muscles;fumigation and washing using TCM was applied.CONCLUSION Combined internal and external treatment with TCM,following the principle of“Prioritize internal treatment before ulceration and emphasize external treatment after ulceration”was effective in our patient with GLM.The prognosis was good.We believe that TCM offered valuable therapeutic benefits in this disease. 展开更多
关键词 Granulomatous mastitis Traditional Chinese medicine ERYTHEMA Nodules in the lower extremities Arthritis in both knees Cough and headache Case report
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Markov branching processes with immigration-migration and resurrection 被引量:5
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作者 LI JunPing LIU ZaiMing 《Science China Mathematics》 SCIE 2011年第5期1043-1062,共20页
We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly in- vestigated in deta... We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly in- vestigated in detail. The explicit expressions for the extinction probabilities and mean extinction times are presented. The ergodicity and stability properties of the process incorporating with resurrection structure are then investigated. The conditions for recurrence, ergodicity and exponential ergodicity are obtained. An explicit expression for the equilibrium distribution is also presented. As a preparation, the criteria for regularity and uniqueness for such structure are firstly established. 展开更多
关键词 Markov branching process immigration migration resurrection regularity extinction recurrence ergodicity收藏本站首页期刊全文库学位论文库会议论文库吾喜杂志注册|登录|我的账户基础科学|工程科技I辑|工程科技II辑|医药卫生科技|信息科技|农业科技|哲学与人文科学|社会科学I辑|社会科学II辑|经济管理高级搜索: 用" Markov branching process immigration "到知网平台检索 点击这里搜索更多...《Science China(Mathematics)》 2011年05期 加入收藏 获取最新 Markov branching processes with immigration-migration and resurrection【摘要】: We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly in- vestigated in detail. The explicit expressions for the extinction probabilities and mean extinction times are presented. The ergodicity and stability properties of the process incorporating with resurrection structure are then investigated. The conditions for recurrence ergodicity and exponential ergodicity are obtained. An explicit expression for the equilibrium distribution is also presented. As a preparation the criteria for regularity and uniqueness for such structure are firstly established.【关键词】 Markov branching process IMMIGRATION MIGRATION RESURRECTION REGULARITY EXTINCTION recur- rence ergodicity Keywords Markov branching process immigration migration resurrection regularity extinction recur-rence ergodicity
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中国的国防支出需求:1960~1999 被引量:5
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作者 赵黎明 陈炳福 《统计研究》 CSSCI 北大核心 2005年第1期25-29,共5页
Constructing the standard neo-clsaaical model of the demand for defense expendi ture and testing the empirical econometric model of the defense expenditures in China,we estimated demand for military expenditure in ter... Constructing the standard neo-clsaaical model of the demand for defense expendi ture and testing the empirical econometric model of the defense expenditures in China,we estimated demand for military expenditure in terms of economic,security and strategic variables in China for both periods:1960~1980 and 1981~1999. Th e results suggest that the change of the defense developing doctrine in China betw een the periods has a most influence to demand for defense expenditures. In 196 0~1980,the determaints of demand for defense expenditures are security environm e nts,the defense expenditures are already exceed the economy of acceptance abilit y. But in 1981~1999,the most influence of factors are lag defense expenditure a nd GDP. 展开更多
关键词 支出需求 China between model 国防 中国 the MOST for and ARE both that of The HAS BUT GDP
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Appraisal of the Production-Oriented Approach: An Introduction 被引量:4
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作者 濮实 《Chinese Journal of Applied Linguistics》 SCIE 2017年第4期452-453,共2页
The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen, 2016). It is also motivated by the ... The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen, 2016). It is also motivated by the aspiration to enhance the quality of foreign language education in other similar pedagogical contexts outside China. A volume of research has been done by Wen Qiufang and her research team, to formulate the theory of POA and to test its effectiveness in classroom pedagogy (e.g. Wen, 2016, 2015; Yang, 2015; Zhang, 2015). At the moment, the POA is still at an early stage of theory building and almost all empirical research is done in the Chinese context. In order to improve the quality of this theory and to make it intelligible to the international academic community, a one-day symposium was held in Beijing Foreign Studies University on May 15, 2017. The symposium was entitled 'The first international forum on innovative foreign language education in China: Appraisal of the POA'. In the forum, leading experts in applied linguistics were invited to discuss the strengths and weaknesses of the POA and the directions for its future development. The symposium was the first attempt for the POA research team to discuss its latest work with international scholars. This Viewpoint section collects the responses of four experts who participated in the symposium, listed in alphabetical order. The collection of articles covers three topics related to the POA: its pedagogical application, its use for teacher training, and its research. Alister Cumming is Professor Emeritus and the former Head of the Centre for Educational Research on Languages and Literacies, University of Toronto, Canada. His article focuses primarily on POA research as an exemplary case of design-based research. Rod Ellis is Research Professor in the School of Education at Curtin University, Australia. He discusses POA in terms of pedagogy, teacher training and research, with both critiques and constructive suggestions. Paul Kei M 展开更多
关键词 The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen 2016). It is also motivated by the aspiration to enhance the quality of foreign language education in other similar pedagogical contexts outside China. A volume of research has been done by Wen Qiufang and her research team to formulate the theory of POA and to test its effectiveness in classroom pedagogy (e.g. Wen 2016 2015 Yang 2015 Zhang 2015). At the moment the POA is still at an early stage of theory building and almost all empirical research is done in the Chinese context. In order to improve the quality of this theory and to make it intelligible to the international academic community a one-day symposium was held in Beijing Foreign Studies University on May 15 2017. The symposium was entitled 'The first international forum on innovative foreign language education in China: Appraisal of the POA'. In the forum leading experts in applied linguistics were invited to discuss the strengths and weaknesses of the POA and the directions for its future development. The symposium was the first attempt for the POA research team to discuss its latest work with international scholars. This Viewpoint section collects the responses of four experts who participated in the symposium listed in alphabetical order. The collection of articles covers three topics related to the POA: its pedagogical application its use for teacher training and its research. Alister Cumming is Professor Emeritus and the former Head of the Centre for Educational Research on Languages and Literacies University of Toronto Canada. His article focuses primarily on POA research as an exemplary case of design-based research. Rod Ellis is Research Professor in the School of Education at Curtin University Australia. He discusses POA in terms of pedagogy teacher training and research with both critiques and constructive suggestions. Paul Kei Mat
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Acetylglutamate kinase is required for both gametophyte function and embryo development in Arabidopsis thaliana 被引量:4
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作者 Jie Huang Dan Chen +5 位作者 Hailong Yan Fei Xie Ying Yu Liyao Zhang Mengxiang Sun Xiongbo Peng 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2017年第9期642-656,共15页
The specific functions of the genes encoding arginine biosynthesis enzymes in plants are not well characterized. We report the isolation and characterization of Arabidopsis thaliana N-acetylglutamate kinase (NAGK), ... The specific functions of the genes encoding arginine biosynthesis enzymes in plants are not well characterized. We report the isolation and characterization of Arabidopsis thaliana N-acetylglutamate kinase (NAGK), which catalyzes the second step of arginine biosynthesis. NAGK is a plastid-localized protein and is expressed during most developmental processes in Arabidopsis. Heterologous expression of the Arabidopsis NAGK gene in a NAGK-deficient Escherichia coli strain fully restores bacterial growth on arginine-deficient medium, nagk mutant pollen tubes grow more slowly than wild type pollen tubes and the phenotype is restored by either specifically through complementation by NAGK in pollen, or exogenous supplementation of arginine, nagk female gametophytes are defective in micropylar pollen tube guidance due to the fact that female gametophyte cell fate specification was specifically affected. Expression of NAGK in synergid cells rescues the defect of nagk female gametophytes. Loss- of-function of NAGK results in Arabidopsis embryos not developing beyond the four-celled embryo stage. The embryo-defective phenotype in nagk/NAGK plants cannot be rescued by watering nagk/NAGK plants with arginine or ornithine supplementation. In conclusion, our results reveal a novel role of NAGK and arginine in regulating gametophyte function and embryo development, and provide valuable insights into arginine transport during embryo development. 展开更多
关键词 Acetylglutamate kinase is required for both gametophyte function and embryo development in Arabidopsis thaliana Figure
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A fast method to diagnose phase transition from amorphous to microcrystalline silicon 被引量:4
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作者 HOU GuoFu XUE JunMing +3 位作者 YUAN YuJie SUN Jian ZHAO Ying GENG XinHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期731-736,共6页
A series of hydrogenated silicon thin films were prepared by the radio frequency plasma enhanced chemical vapor deposition method (RF-PECVD) with various si-lane concentrations. The influence of silane concentration o... A series of hydrogenated silicon thin films were prepared by the radio frequency plasma enhanced chemical vapor deposition method (RF-PECVD) with various si-lane concentrations. The influence of silane concentration on structural and elec-trical characteristics of these films was investigated to study the phase transition region from amorphous to microcrystalline phase. At the same time,optical emis-sion spectra (OES) from the plasma during the deposition process were monitored to get information about the plasma properties,Raman spectra were measured to study the structural characteristics of the deposited films. The combinatorial analysis of OES and Raman spectra results demonstrated that the OES can be used as a fast method to diagnose phase transition from amorphous to microcrystalline silicon. At last the physical mechanism,why both OES and Raman can be used to diagnose the phase transition,was analyzed theoretically. 展开更多
关键词 amorphous silicon microcrystalline silicon phase transition optical emission spectroscopy
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论贝克风险社会理论的解释框架 被引量:4
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作者 董才生 王彦力 《自然辩证法研究》 CSSCI 北大核心 2015年第1期70-74,共5页
贝克突破传统社会理论的解释框架,创建了由"建构论的实在论"的认识论基本预设、"既是…又是…"的分析模式以及第二现代性或现代化理论所构成的、新的社会理论的解释框架。这一新的解释框架具有"混合性"或... 贝克突破传统社会理论的解释框架,创建了由"建构论的实在论"的认识论基本预设、"既是…又是…"的分析模式以及第二现代性或现代化理论所构成的、新的社会理论的解释框架。这一新的解释框架具有"混合性"或"融合性"的基本特征。贝克基于这一新的解释框架建构了独具特色的风险社会理论。贝克风险社会理论的解释框架实现了对传统社会理论解释框架的一次"革命性变革",为我们认识与研究当代西方社会的转型、当代世界的深刻变迁提供了新启示、开辟了新视野。研究贝克风险社会理论的解释框架对于更为深入地理解与把握他的风险社会理论特色,建构适合于当代世界特征的、新的社会理论的解释框架具有非常重要的方法论启示意义。 展开更多
关键词 建构论的实在论 既是…又是… 第二现代性或现代化 第三条道路
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从“非此即彼”到“亦此亦彼”——论文学阐释的一个当代转向
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作者 庞弘 《中国文艺评论》 2023年第10期73-85,I0004,共14页
阐释是人文学术中的一个核心议题。在当代,文学阐释出现了从“非此即彼”到“亦此亦彼”的深刻转向。长期以来,面对客观主义和相对主义的纠葛,研究者习惯于采取“非此即彼”的做法,将其中一方奉若圭臬而无视另一方的存在。晚近,研究者... 阐释是人文学术中的一个核心议题。在当代,文学阐释出现了从“非此即彼”到“亦此亦彼”的深刻转向。长期以来,面对客观主义和相对主义的纠葛,研究者习惯于采取“非此即彼”的做法,将其中一方奉若圭臬而无视另一方的存在。晚近,研究者越来越多地表现出“亦此亦彼”的态度,试图探寻客观主义和相对主义的交叠互涉之处,从而在同一与差异、过去与未来、明晰与含混、恢复与怀疑、结构与事件等貌似难以调和的二元对立之间取得平衡。“亦此亦彼”的阐释之道为我们重审当代文论话语提供了契机,同时也在一定程度上有助于中西方阐释思想的良性对话和创造转换。 展开更多
关键词 阐释 客观主义 相对主义 非此即彼 亦此亦彼
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PREDICTION OF MAXIMUM SCOUR DEPTH AROUND LARGE DIAMETER CYLINDER UNDER THE EFFECTS OF BOTH WAVE AND CURRENT 被引量:2
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作者 LILin-pu CUILi 《Journal of Hydrodynamics》 SCIE EI CSCD 2005年第1期74-79,共6页
Physical model tests were counducted to predict local scour and maximum scour depth around the large diameter cylinders located in the (sand) seabed under the action of both wave and current . According to the result ... Physical model tests were counducted to predict local scour and maximum scour depth around the large diameter cylinders located in the (sand) seabed under the action of both wave and current . According to the result of tests, an analysis was made on all the factors influencing the scour. The results shows that for the seabed with relative fine grains in shallow water (0.07<h/L≤0.28),when the relative diameter D/L of the cylinder is within 0.3 0.7,the main effective scour factors around the cylinder in the seabed are diameter D of the cylinder, the wave height H, the wave length L, the velocity V c of the current and the parameters related to the seabed soil texture. The main parameters influecing the maximum scour depth were analyzed, and the test data were syntherized, to obtain the formula predicting the scour depth around the large diameter cylinder under the of both wave and current. 展开更多
关键词 offshore engineering the effects of both wave and current large diameter cylinder local scour
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Both structure and function of human monoclonal antibodies contribute to enhancement of Zika virus infectivity in vitro 被引量:2
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作者 Min Li Xin Wang +7 位作者 Qihui Wang Lei Yu Lanfeng Wang Jinghua Yan Fuchun Zhang Linqi Zhang George F.Gao Xia Jin 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第12期1396-1398,共3页
Dear Editor,Antibody-dependent enhancement(ADE)has long been recognized for dengue virus(DENV)in vitro and in vivo.It is now clear that antibodies to DENV can also enhance Zika virus(ZIKV)infection in vitro,and ... Dear Editor,Antibody-dependent enhancement(ADE)has long been recognized for dengue virus(DENV)in vitro and in vivo.It is now clear that antibodies to DENV can also enhance Zika virus(ZIKV)infection in vitro,and vice versa(Dejnirattisai et al.,2016;Stettler et al.,2016).The characteristics of enhancing antibodies,however,remain elusive. 展开更多
关键词 both structure and function human monoclonal
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