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Influence of After-School Tutoring on Reading Comprehension Skills of Chinese Primary School Students with Dyslexia:A Mixed-Methods Study
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作者 Jin Ma 《Journal of Contemporary Educational Research》 2025年第7期188-196,共9页
This study explores the influence of after-school tutoring on reading comprehension skills of students with dyslexia(DD)in grades 3-5 in China and its participating factors.Using a mixed-methods design,the quantitativ... This study explores the influence of after-school tutoring on reading comprehension skills of students with dyslexia(DD)in grades 3-5 in China and its participating factors.Using a mixed-methods design,the quantitative data(GORT-4 reading test)of 50 public primary school students in Qingdao and their parents’feedback were collected through questionnaires,supplemented by semi-structured interviews with eight parents for qualitative analysis.The findings are as follows:(1)Family socioeconomic status and parents’awareness of DD are the key factors to participate in after-school counseling;(2)The students who participated in the after-school counseling performed significantly better in the GORT-4 comprehension test(P<0.05);(3)Counseling makes up for the lack of classroom learning through personalized strategies(such as multi-sensory teaching and phonological awareness training),but parents’psychological support is the core of successful intervention.The necessity of early targeted intervention was emphasized,and practical enlightenment was provided for the educational support system of DD students in China. 展开更多
关键词 Dyslexia After-school counseling Reading comprehension STUDENTS study on hybrid method Chinese education
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Association between acupuncture and live birth rates after fresh embryo transfer:A cohort study based on different propensity score methods
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作者 Xiao-yan Zheng Zi-yi Jiang +9 位作者 Yi-ting Li Chao-liang Li Hao Zhu Zheng Yu Si-yi Yu Li-li Yang Song-yuan Tang Xing-yu Lü Fan-rong Liang Jie Yang 《Journal of Integrative Medicine》 2025年第5期528-536,共9页
Objective:To explore the association between acupuncture during controlled ovarian hyperstimulation(COH)and the live birth rate(LBR)using different propensity score methods.Methods:In this retrospective cohort study,e... Objective:To explore the association between acupuncture during controlled ovarian hyperstimulation(COH)and the live birth rate(LBR)using different propensity score methods.Methods:In this retrospective cohort study,eligible women who underwent a COH were divided into acupuncture and non-acupuncture groups.The primary outcome was LBR,as determined by propensity score matching(PSM).LBR was defined as the delivery of one or more living infants that reached a gestational age over 28 weeks after embryo transfer.The propensity score model encompassed 16 confounding variables.To validate the results,sensitivity analyses were conducted using three additional propensity score methods:propensity score adjustment,inverse probability weighting(IPW),and IPW with a"doubly robust”estimator.Results:The primary cohort encompassed 9751 patients(1830[18.76%]in the acupuncture group and7921[81.23%]in the non-acupuncture group).Following 1:1 PSM,a higher LBR was found in the acupuncture cohort(41.4%[755/1824]vs 36.4%[664/1824],with an odds ratio of 1.23[95%confidence interval,1.08-1.41]).Three additional propensity score methods produced essentially similar results.The risk of serious adverse events did not significantly differ between the two groups.Conclusion:This retrospective study revealed an association between acupuncture and an increased LBR among patients undergoing COH,and that acupuncture is a safe and valuable treatment option. 展开更多
关键词 ACUPUNCTURE Fresh embryo transfer Live birth rate Propensity score Retrospective study Cohort study
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Theoretical Study and Slip Effect Analysis of Elastic Calculation Methods for Steel-Concrete Composite Beams
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作者 Shaohui Chu Xiangkai Zeng Zhixin Guo 《Journal of World Architecture》 2025年第5期67-74,共8页
Steel-concrete composite beams,due to their superior mechanical properties,are widely utilized in engineering structures.This study systematically investigates the calculation methods for internal forces and load-bear... Steel-concrete composite beams,due to their superior mechanical properties,are widely utilized in engineering structures.This study systematically investigates the calculation methods for internal forces and load-bearing capacity of composite beams based on elastic theory,with a focus on the transformed section method and its application under varying neutral axis positions.By deriving the geometric characteristics of the transformed section and incorporating a reduction factor accounting for slip effects,a computational model for sectional stress and ultimate load-bearing capacity is established.The results demonstrate that the slip effect significantly influences the flexural load-bearing capacity of composite beams.The proposed reduction factor,which considers the influence of the steel beam’s top flange thickness,offers higher accuracy compared to traditional methods.These findings provide a theoretical foundation for the design and analysis of composite beams,with significant practical engineering value. 展开更多
关键词 Composite beam Elastic calculation Slip effect Theoretical study
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A Comprehensive Study on Application and Prospect of Hydrogel Detection Methods
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作者 Caixia Chen Pengyu Liu +3 位作者 Changhua Wang Yanyan Xie Wei Wang Xiaomin Kang 《Journal of Polymer Materials》 2025年第3期621-660,共40页
Due to their high water content,stimulus responsiveness,and biocompatibility,hydrogels,which are functional materials with a three-dimensional network structure,are widely applied in fields such as biomedicine,environ... Due to their high water content,stimulus responsiveness,and biocompatibility,hydrogels,which are functional materials with a three-dimensional network structure,are widely applied in fields such as biomedicine,environmental monitoring,and flexible electronics.This paper provides a systematic review of hydrogel charac-terization methods and their applications,focusing on primary evaluation techniques for physical properties(e.g.,mechanical strength,swelling behavior,and pore structure),chemical properties(e.g.,composition,crosslink density,and degradation behavior),biocompatibility,and functional properties(e.g.,drug release,environmental stimulus response,and conductivity).It analyzes the challenges currently faced by characterization methods,such as a lack of standardization,difficulties in dynamic monitoring,an insufficient micro-macro correlation,and poor adaptability to complex environments.It proposes solutions,such as a hierarchical standardization system,in situ imaging technology,cross-scale characterization,and biomimetic testing platforms.Looking ahead,hydrogel characterization techniques will evolve toward intelligent,real-time,multimodal coupling and standardized approaches.These techniques will provide superior technical support for precision medicine,environmental restoration,and flexible electronics.They will also offer systematic methodological guidance for the performance optimization and practical application of hydrogel materials. 展开更多
关键词 HYDROGEL characterization methods PROPERTIES STANDARDIZATION APPLICATION
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Trajectory and determinants of family resilience in caregivers of preterm infants:A mixed-methods study
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作者 Caihui Su Dun Liu +3 位作者 Shanshan Xu Yongfen Wang Yuehua Lin Qingqing Lian 《International Journal of Nursing Sciences》 2025年第6期541-550,共10页
Objective:To investigate the dynamic trajectory,predictors,and underlying adaptation mechanisms of family resilience(FR)among Chinese families with preterm infants(PIs)from birth to six months.Methods:Guided by Ecolog... Objective:To investigate the dynamic trajectory,predictors,and underlying adaptation mechanisms of family resilience(FR)among Chinese families with preterm infants(PIs)from birth to six months.Methods:Guided by Ecological Systems Theory,a convergent parallel mixed-methods study was conducted in the Neonatal Intensive Care Unit(NICU)of a tertiary hospital in Fujian Province,China,from June 2023 to June 2024.Quantitative data were collected from 202 caregivers selected by convenience sampling at four time points:at birth(T0),42 days postpartum(T1),3 months postpartum(T2),and 6 months postpartum(T3).Generalized Estimating Equations(GEE)was used to analyze scale score differences across time points and explore factors influencing FR.Qualitative data were collected through semi-structured interviews with 14 caregivers recruited by maximum variation purposive sampling and analyzed using Colaizzi’s phenomenological approach.After conducting separate data analyses,the findings were integrated through side-by-side comparison and joint display.Results:Quantitative results revealed a non-linear,“V”-shaped trajectory of FR,significantly influenced by educational level,conception via assisted reproduction,farming occupation,coping style,psychological resilience,family functioning,and social support.Qualitative findings identified four themes:initial uncertainty and emotional distress,post-discharge anxiety,gradual adaptation,and eventual stabilization.Integrated mixed-methods findings revealed that the initial confusion phase demands a comprehensive response to family needs(T0);the post-discharge bottleneck requires addressing the care capability-needs gap(T1);the role adaptation phase is pivotal for enhancing internal family resources(T2);and the family-work transition necessitates enhanced work-family facilitation(T3).Conclusions:This study systematically identifies the unique“V”-shaped trajectory of FR in Chinese families with PIs and its key influencing factors,and accurately analyzes their dynamic experiences and adaptation across four stages.These findings provide an empirical basis for stage-specific targeted interventions,strongly support the practical advancement of the family-centered care model,and deliver critical guidance for enhancing FR. 展开更多
关键词 CAREGIVERS Ecological systems theory Family resilience Longitudinal study MIXED-methods Preterm infants
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Effects of spatial heterogeneity on pseudo-static stability of coal mine overburden dump slope,using random limit equilibrium and random finite element methods:A comparative study
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作者 Madhumita Mohanty Rajib Sarkar Sarat Kumar Das 《Earthquake Engineering and Engineering Vibration》 2025年第1期83-99,共17页
Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump mate... Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump materials is imperative for an adequate evaluation of the seismic stability of OB dump slopes.In this study,pseudo-static seismic stability analyses are carried out for an OB dump slope by considering the material parameters obtained from an insitu field investigation.Spatial heterogeneity is simulated through use of the random finite element method(RFEM)and the random limit equilibrium method(RLEM)and a comparative study is presented.Combinations of horizontal and vertical spatial correlation lengths were considered for simulating isotropic and anisotropic random fields within the OB dump slope.Seismic performances of the slope have been reported through the probability of failure and reliability index.It was observed that the RLEM approach overestimates failure probability(P_(f))by considering seismic stability with spatial heterogeneity.The P_(f)was observed to increase with an increase in the coefficient of variation of friction angle of the dump materials.Further,it was inferred that the RLEM approach may not be adequately applicable for assessing the seismic stability of an OB dump slope for a horizontal seismic coefficient that is more than or equal to 0.1. 展开更多
关键词 coal mine overburden dump slope random limit equilibrium method random finite element method seismic slope stability spatial heterogeneity
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Study on Improving the Teaching Effect of Mathematical Methods for Physics Using Manim Animation Technology
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作者 Yong Niu Linhao Wang +1 位作者 Ying Wang Pan Wang 《Journal of Contemporary Educational Research》 2025年第10期215-222,共8页
With the development of educational digitalization,how to effectively apply digital animation technology to traditional classroom teaching has become an urgent problem to be solved.This study explores the application ... With the development of educational digitalization,how to effectively apply digital animation technology to traditional classroom teaching has become an urgent problem to be solved.This study explores the application of Manim in the course of Mathematical Methods for Physics.Taking the visualization of Fourier series,complex numbers,and other content as examples,it improves students’understanding of complex and abstract mathematical physics concepts through dynamic and visual teaching methods.The teaching effect shows that Manim helps to enhance students’learning experience,improve teaching efficiency and effectiveness,and has a positive impact on students’active learning ability.The research in this paper can provide references and inspiration for the educational digitalization of higher education. 展开更多
关键词 Manim Mathematical methods for physics Educational digitalization Animation visualization
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A Study on the Investigation Methods of Jesuit Father d'Entrecolles Regarding Jingdezhen Porcelain Production Techniques
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作者 YANG Min LI Xue +1 位作者 MIAO Lifeng ZHENG Naizhang 《Cultural and Religious Studies》 2025年第9期518-525,共8页
In the early 18th century,to meet Europe's urgent demand for Jingdezhen's ceramic production techniques,French Jesuit missionary François Xavier d'Entrecolles traveled to Jingdezhen,Jiangxi.While cond... In the early 18th century,to meet Europe's urgent demand for Jingdezhen's ceramic production techniques,French Jesuit missionary François Xavier d'Entrecolles traveled to Jingdezhen,Jiangxi.While conducting missionary work,he thoroughly investigated local porcelain-making techniques.He compiled his findings into two lengthy letters and sent samples of porcelain raw materials to Europe,successfully disseminating Jingdezhen's ceramic artistry to the continent.D'Entrecolles skillfully integrated the protective function of his religious identity,the resource coordination capabilities of political networks,the documentation methods of empirical science,and a localized infiltration strategy,constructing a four-dimensional investigative framework of"missionary integration-observation and interviews-literature review-experimental verification"through Broussonetia papyrifera.These systematic research methods enabled him to comprehensively master Jingdezhen's porcelain technology at the time,establishing him as the pioneer of Western systematic studies on Chinese ceramics and creating a new paradigm of"field research+scientific empiricism"in early cross-cultural technological transmission. 展开更多
关键词 the society of Jesus Father d'Entrecolles Jingdezhen porcelain manufacturing techniques investigation methods
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Retrospective comparative study of different surgical methods for gastric ulcer perforation:Efficacy and postoperative complications
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作者 Yu-Fan Pang Liang Shu Cheng-Wei Xia 《World Journal of Gastrointestinal Surgery》 2025年第2期154-160,共7页
BACKGROUND Gastric ulcer perforation is a critical condition that can lead to significant morbidity and mortality if not promptly addressed.It is often the result of chronic peptic ulcer disease,which is characterized... BACKGROUND Gastric ulcer perforation is a critical condition that can lead to significant morbidity and mortality if not promptly addressed.It is often the result of chronic peptic ulcer disease,which is characterized by a breach in the gastric wall due to ulceration.Surgical intervention is essential for managing this life-threatening complication.However,the optimal surgical technique remains debatable among clinicians.Various methods have been employed,including simple closure,omental patch repair,and partial gastrectomy,each with distinct advantages and disadvantages.Understanding the comparative efficacy and postoperative outcomes of these techniques is crucial for improving patient care and surgical decision-making.This study addresses the need for a comprehensive analysis in this area.AIM To compare the efficacy and postoperative complications of different surgical methods for the treatment of gastric ulcer perforation.METHODS A retrospective analysis was conducted on 120 patients who underwent surgery for gastric ulcer perforation between September 2020 and June 2023.The patients were divided into three groups based on the surgical method:Simple closure,omental patch repair,and partial gastrectomy.The primary outcomes were the operative success rate and incidence of postoperative complications.Secondary outcomes included the length of hospital stay,recovery time,and long-term quality of life.RESULTS The operative success rates for simple closure,omental patch repair,and partial gastrectomy were 92.5%,95%,and 97.5%,respectively.Postoperative complications occurred in 20%,15%,and 17.5%of patients in each group,respectively.The partial gastrectomy group showed a significantly longer operative time(P<0.001)but the lowest rate of ulcer recurrence(2.5%,P<0.05).The omental patch repair group demonstrated the shortest hospital stay(mean 7.2 days,P<0.05)and fastest recovery time.CONCLUSION While all three surgical methods showed high success rates,omental patch repair demonstrated the best overall outcomes,with a balance of high efficacy,low complication rates,and shorter recovery time.However,the choice of the surgical method should be tailored to individual patient factors and the surgeon’s expertise. 展开更多
关键词 Gastric ulcer perforation Surgical methods Simple closure Omental patch repair Partial gastrectomy Postoperative complications
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AI-Powered Research on Translation Strategies and Methods and Its Advantages and Disadvantages:A Case Study of the Translation of Ambulance Lectures:First Aid to the Injured
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作者 Yuqiong Long Xiaoling Zhou 《Journal of Contemporary Educational Research》 2025年第1期189-197,共9页
This article,empowered by ChatGPT and through retrieving relevant historical literature,explores how the translator Sun Yat-sen flexibly employed strategies like domestication and foreignization,as well as methods lik... This article,empowered by ChatGPT and through retrieving relevant historical literature,explores how the translator Sun Yat-sen flexibly employed strategies like domestication and foreignization,as well as methods like omission,addition,and modification in his translation of Ambulance Lectures:First Aid to the Injured.Additionally,the research highlights the use of ChatGPT as a tool to assist in the study.While ChatGPT is able to provide comprehensive knowledge quickly and proper translations,improvements are still needed in terms of image accuracy and citation generation.By providing specific context,probing for factual evidence,clarifying the reference objects,and narrowing the scope,prompts can be gradually refined for increasingly satisfactory outcomes. 展开更多
关键词 Artificial intelligence Translation strategies and methods Ambulance Lectures:First Aid to the Injured Sun Yat-sen
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Ethical awareness and issues in gastrointestinal endoscopy practice:A survey study
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作者 Yi Qin Ming-Yang Shi 《World Journal of Gastroenterology》 2026年第1期151-157,共7页
BACKGROUND Gastrointestinal endoscopy technology has significantly improved the diagnostic accuracy and the successful treatment of gastrointestinal diseases.However,a series of ethical issues have emerged,such as exp... BACKGROUND Gastrointestinal endoscopy technology has significantly improved the diagnostic accuracy and the successful treatment of gastrointestinal diseases.However,a series of ethical issues have emerged,such as expanding treatment indications,which affect the fair distribution of medical resources.There is limited research on ethical issues in the field of digestive endoscopy.AIM To investigate the level of ethical awareness among gastrointestinal endoscopy practitioners and analyze the ethical issues involved in gastrointestinal endoscopy technology.METHODS A questionnaire survey was performed to collect relevant data(gender,age,degree of education,professional title,personnel category,the level of understanding medical ethical principles,ethics training and its learning pathways)from gastrointestinal endoscopy practitioners at the Second Hospital of Dalian Medical University and Dalian Friendship Hospital,including licensed physicians and nurses(including trainees and graduate students).RESULTS The majority of gastrointestinal endoscopy practitioners have received training on ethics,but there is still considerable room for improvement in their ethical awareness.Different learning pathways may affect the mastery of ethical principles, and understanding of ethical principles is more easily achieved through hospital ethics institutions.CONCLUSIONTo address the ethical issues in gastrointestinal endoscopy technology, it is necessary to enhance the humanisticeducation of gastrointestinal endoscopy practitioners, incorporate ethical standards into the technology assessmentprocess, and establish a patient-centered diagnostic and treatment model to improve the ethical awareness of practitionersand achieve a balance between technology and ethics. 展开更多
关键词 Gastrointestinal endoscopy Ethical awareness Ethical issues Medical ethics Survey study
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Comparative Study on Four Methods for Quick Extraction of Sorghum Genomic DNA 被引量:3
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作者 高建明 夏卜咸 +5 位作者 杨洪 曲荣桂 桂枝 罗峰 裴忠有 孙守钧 《Agricultural Science & Technology》 CAS 2011年第5期686-687,744,共3页
[Objective] This study was to find out a quick,simple,and low-cost method for the extraction of sorghum genomic DNA.[Method] Four plant genomic DNA extraction methods based on CTAB,including liquid nitrogen grinding m... [Objective] This study was to find out a quick,simple,and low-cost method for the extraction of sorghum genomic DNA.[Method] Four plant genomic DNA extraction methods based on CTAB,including liquid nitrogen grinding method(method I),buffer grinding method(method II),drying grinding method(method III)and directly grinding method(method IV),were used to extract the sorghum genomic DNA from leaves;further the quantity and quality of the yielded DNA were detected by gel electrophoresis,SSR-PCR and SRAP-PCR.[Result] These four methods performed no remarkable difference in DNA product.The method I and method II produced DNA with higher purity and better integrity,which,especially from method I,is effective for SRAP-PCR and SSR-PCR.While the DNA extracted via method III and method IV had less integrality and lower purity,and only effective in SSR-PCR.[Conclusion] Enough amount of sorghum genomic DNA to perform tens of PCR could be quickly extracted using all these four methods.The DNA obtained via method I and method II had a broader application spectrum(SRAP,RAPD,ISSR and SSR)than that via method III and method IV which is only proper for PCR targeting small DNA fragments(SSR). 展开更多
关键词 Sorghum bicolor LEAF Genomic DNA CTAB method Quick extraction
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Comparison study on calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949 被引量:1
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作者 淳庆 Van Balen Koenraad 韩宜丹 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期529-534,共6页
In order to study the calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949, tests on the mechanical performance of 66 rebars from different modem Chinese concrete buildings, t... In order to study the calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949, tests on the mechanical performance of 66 rebars from different modem Chinese concrete buildings, the concrete compressive strength of 12 modem Chinese concrete buildings, and the concrete cover thickness of 9 modem Chinese concrete buildings are carried out; and the actual material properties and structural conformations of modem Chinese concrete buildings are obtained. Then, the comparison on calculation methods of bending behavior including the original Chinese calculation method, the present Chinese calculation method, the present American calculation method and the present European calculation method is studied. The results show that the original Chinese calculation method of bending behavior is based on the allowable stress calculation method, and the design safety factors are 3.55 to 4. 0. In term of the calculation area of longitudinal rebars of reinforced concrete beams, without considering earthquake action, the original Chinese structural calculation method is safer than the present Chinese structural calculation method, the present European structural calculation method, and the present American structural calculation method. The results can provide support for the structural safety assessments of modem Chinese reinforced concrete buildings. 展开更多
关键词 reinforced concrete beam the Republic of China era from 1912 to 1949 bending behavior calculation method comparative study
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Study on Determination Methods of Important Landscapes along the Mainstream of Yellow River
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作者 商崇菊 郝志斌 +1 位作者 古今用 吕东玉 《Journal of Landscape Research》 2009年第3期35-41,共7页
According to the response relationship between landscape and water resource,the selection principle of important landscapes was determined from the perspectives of nature and history in this study,and determination me... According to the response relationship between landscape and water resource,the selection principle of important landscapes was determined from the perspectives of nature and history in this study,and determination methods or steps of important landscapes along the mainstream of Yellow River were also established to select important landscapes that should be protected. 展开更多
关键词 MAINSTREAM of YELLOW RIVER Important LANDSCAPE DETERMINATION method
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A Study on the Leading-in Methods in English Class Teaching
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作者 周明霞 《海外英语》 2014年第20期83-84,87,共3页
The article mainly discusses the necessity of leading-in in English class and gives some effective methods of Leadingin on how to improve students’learning enthusiasm.
关键词 leading-in NECESSITY PRINCIPLE effective methods
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Translation Compensation Methods under Skopostheorie:A Comparative Study on Four-character Chengyu Translation Compensation in Hong Lou Meng
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作者 邓雪玲 《海外英语》 2011年第6X期209-210,共2页
This article attempts to apply skopos theory and make a comparative study of the translation compensation methods of two English versions of Hong Lou Meng in terms of four-character chengyu from the linguistic perspec... This article attempts to apply skopos theory and make a comparative study of the translation compensation methods of two English versions of Hong Lou Meng in terms of four-character chengyu from the linguistic perspective. 展开更多
关键词 TRANSLATION of FOUR-CHARACTER chengyu COMPENSATION methods skopotheories LINGUISTIC perspective
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A Comparative Study on Three Methods for the Extraction of Total RNA from Pinus bungeana 被引量:3
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作者 王雁 李贞 +3 位作者 刘小侠 倪慧 毛红 张青文 《Agricultural Science & Technology》 CAS 2011年第5期663-665,共3页
[Objective] The aim of this study was to compare three RNA extraction methods and thus find out the suitable one for isolating intact and high quality total RNA from Pinus bungeana.[Method] Employing three extraction ... [Objective] The aim of this study was to compare three RNA extraction methods and thus find out the suitable one for isolating intact and high quality total RNA from Pinus bungeana.[Method] Employing three extraction methods of Trizol,RNeasy Mini Kit,LiCl precipitation,total RNAs of P.bungeana were extracted from pine leaf samples,and their integrity and purity were detected via agarose gel electrophoresis and spectrophotometry for a comparative study.[Result] Among the three extraction methods,LiCl precipitation method demonstrated higher yield and better integrity of total extracted RNA,with OD260/OD280 ratio between 1.8-2.0 and clear 28 S and 18 S bands in electrophoresis pattern.[Conclusion] LiCl precipitation method could be used to extract highly pure and intact total RNA from P.bungeana. 展开更多
关键词 Pinus bungeana Total RNA Extraction method cDNA library
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QSAR Study of Nitrobenzenes’ Toxicity to Tetrahymena Pyriformis Using Semi-empirical Quantum Chemical Methods 被引量:16
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作者 闫秀芬 肖鹤鸣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第1期7-14,共8页
The molecular geometries and electronic structures of 30 nitrobenzenes have been calculated by using semi-empirical MO AM1 and PM3 methods. EHOMO, ELUMO, ENHOMO, ENLUMO, AE, QNO2, Qc and V were selected as the structu... The molecular geometries and electronic structures of 30 nitrobenzenes have been calculated by using semi-empirical MO AM1 and PM3 methods. EHOMO, ELUMO, ENHOMO, ENLUMO, AE, QNO2, Qc and V were selected as the structural descriptors. The acute toxicity (-log/C50) of nitrobenzenes to tetrahymena pyriformis along with the above eight structural parameters was used to establish the quantitative structure-activity relationships (QSARs). The results indicate that the established model based on AM I method is superior to that on PM3 method not only for the stability but also for the predictive powers of the model. Based on AM1 parameters, a further classifying discussion was presented for the study of nitrobenzene toxic mechanism. The results show that the substituents, nitro group and halogen substituents on the aromatic ring are crucial to the chemicals' toxicity. For nitrobenzenes without halogen or other substituent, the reduction of nitro group is the main route. However, for those with halogen substituents, their next lowest unoccupied molecular orbital may take part in the toxic action betweeen the chemicals and macromolecules, and ENLUMO has the most important effect on these chemicals' toxicity. 展开更多
关键词 NITROBENZENES TOXICITY QSAR semi-empirical MO orbital methods
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Determination of focal depth by two waveform-based methods:A case study for the 2008 Panzhihua earthquake 被引量:19
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作者 Zhenjie Wang Jiajun Chong +1 位作者 Sidao Ni Barbara Romanowicz 《Earthquake Science》 CSCD 2011年第4期321-328,共8页
With the 2008 Ms6.1 Panzhihua earthquake as a case study, we demonstrate that the focal depth of the main shock can be well constrained with two approaches: (1) using the depth phase sPL and (2) using full wavefo... With the 2008 Ms6.1 Panzhihua earthquake as a case study, we demonstrate that the focal depth of the main shock can be well constrained with two approaches: (1) using the depth phase sPL and (2) using full waveform inversion of local and teleseismic data. We also show that focal depths can be well constrained using the depth phase sPL with single broadband seismic station. Our study indicates that the main shock is located at a depth of ii kin, much shallower than those from other studies, confirming that the earthquake occurs in upper crust. Aftershocks are located in the depth range of 11 16 kin, which is consistent with a ruptured near vertical fault whose width is about 10 km, as expected for an Ms6.1 earthquake. 展开更多
关键词 Panzihua earthquake focal depth waveform inversion depth phase waveform comparison method
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Application of computational methods in genetic study ofinflammatory bowel disease 被引量:3
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作者 Jin Li Zhi Wei Hakon Hakonarson 《World Journal of Gastroenterology》 SCIE CAS 2016年第3期949-960,共12页
Genetic factors play an important role in the etiology of inflammatory bowel disease(IBD). The launch of genome-wide association study(GWAS) represents a landmark in the genetic study of human complex disease. Concurr... Genetic factors play an important role in the etiology of inflammatory bowel disease(IBD). The launch of genome-wide association study(GWAS) represents a landmark in the genetic study of human complex disease. Concurrently, computational methods have undergone rapid development during the past a few years, which led to the identification of numerous disease susceptibility loci. IBD is one of the successful examples of GWAS and related analyses. A total of 163 genetic loci and multiple signaling pathways have been identified to be associated with IBD. Pleiotropic effects were found for many of these loci; and risk prediction models were built based on a broad spectrum of genetic variants. Important gene-gene, gene-environment interactions and key contributions of gut microbiome are being discovered. Here we will review the different types of analyses that have been applied to IBD genetic study, discuss the computational methods for each type of analysis, and summarize the discoveries made in IBD research with the application of these methods. 展开更多
关键词 Inflammatory BOWEL disease Computationalmethods GENOME-WIDE association study Pathwayanalysis Gene-gene INTERACTION Gene-environmentinteraction PLEIOTROPY Risk prediction
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