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Intra-specific genetic relationship analyses of Elaeagnus angustifolia based on RP-HPLC biochemical markers 被引量:1
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作者 WANG Qiang RUAN Xiao +2 位作者 HUANG Jun-hua XU Ning-yi YAN Qi-chuan 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第4期272-278,共7页
Elaeagnus angustifolia Linn. has various ecological, medicinal and economical uses. An approach was established using RP-HPLC (reversed-phase high-performance liquid chromatography) to classify and analyse the intra... Elaeagnus angustifolia Linn. has various ecological, medicinal and economical uses. An approach was established using RP-HPLC (reversed-phase high-performance liquid chromatography) to classify and analyse the intra-specific genetic relationships of seventeen populations of E. angustifolia, collected from the Xinjiang areas of China. Chromatograms of alcohol-soluble proteins produced by seventeen populations of E. angustifolia, were compared. Each chromatogram of alcohol-soluble proteins came from a single seed of one wild plant only. The results showed that when using a Waters Delta Pak. C 18, 5μm particle size reversed phase column (150 mm×3.9mm), a linear gradient of 25%-60% solvent B with flow rate of 1 ml/min and run time of 67 min, the chromatography yielded optimum separation of E. angustifolia alcohol-soluble proteins. Representative peaks in each population were chosen according to peak area and occurrence in every seed. The converted data on the elution peaks of each population were different and could be used to represent those populations. GSC (genetic similarity coefficients) of 41% to 62% showed a medium degree of genetic diversity among the populations in these eco-areas. Cluster analysis showed that the seventeen populations orE. angustifolia could be divided into six clusters at the GSC=0.535 level and indicated the general and unique biochemical markers of these clusters. We suggest that E. angustifolia distribution in these eco-areas could be classified into six variable species. RP-HPLC was shown to be a rapid, repeatable and reliable method for E. angustifolia classification and identification and for analysis of genetic diversity. 展开更多
关键词 Elangustifolia intra-specific genetic relationship Genetic diversity Biochemical marker
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Intra-specific relationships among Tibetan Eared-pheasants based on randomly amplified polymorphic DNA(RAPD)analysis
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作者 DING Wei ZHANG Zhengwang +3 位作者 CHANG Jiang ZHANG Er WU Xiushan ZHANG Jinguo 《Frontiers in Biology》 CSCD 2006年第4期394-397,共4页
The Tibetan Eared-pheasant Crossoptilon harmani is a rare species native to China.A captive population has been established in the Beijing Zoo since 1999.In order to determine the kinship of the offsprings in 2001,ran... The Tibetan Eared-pheasant Crossoptilon harmani is a rare species native to China.A captive population has been established in the Beijing Zoo since 1999.In order to determine the kinship of the offsprings in 2001,randomly amplified polymorphic DNA(RAPD)was used to examine the parenthood of seven Tibetan Eared-pheasants in the Beijing Zoo.To amplify the genomic DNA of each individual,53 arbitrary primers were selected.The results of amplifications showed that 14 primers had clear and distinct RAPD patterns.Totally,226 amplified fragments were generated by RAPD in this study.Cluster analysis of the seven Tibetan Eared-pheasants indicated that all the four young birds had the same father(No.5 male).This study provides a practical method to determine the relationship of offsprings whose parents are unknown in birds. 展开更多
关键词 Tibetan Eared-pheasant Crossoptilon harmani genetic relationship random amplified polymorphic DNA(RAPD)
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Quantitative pollen-vegetation relationships in southern subtropical evergreen broadleaved forests in China and the effects of human disturbance
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作者 Qiuchi WAN Haoxin YE +7 位作者 Kangyou HUANG Xiangyue LONG Liping TIAN Xiao ZHANG Cong CHEN Yaze ZHANG Kunshan BAO Zhuo ZHENG 《Science China Earth Sciences》 2026年第2期590-600,共11页
The quantitative relationship between modern pollen and vegetation provides a critical foundation for reconstructing past vegetation,with relative pollen productivity(RPP)serving as a key calibration parameter.However... The quantitative relationship between modern pollen and vegetation provides a critical foundation for reconstructing past vegetation,with relative pollen productivity(RPP)serving as a key calibration parameter.However,in subtropical evergreen broadleaved forests(SEBFs)in China,RPP studies remain scarce,and the impact of human disturbances on RPP estimates has yet to be adequately assessed,limiting the accuracy of quantitative palaeovegetation reconstructions.This study was conducted in Dinghu Mountain Nature Reserve and its surrounding areas in Zhaoqing,Guangdong Province,and included 31 sampling sites.We performed pollen analysis alongside detailed vegetation surveys and utilized ERV submodel 2 and Prentice’s model to estimate the RPP of 9 common plant taxa in the southern SEBFs.There was a particular focus on evaluating the interference effects of bamboo plantations on the estimation of RPP.The results indicate that bamboo within the family Poaceae contributes minimally to surface soil Poaceae pollen because of its unique flowering characteristics,such as long flowering cycles and monocarpic reproduction.The incorporation of bamboo into the Poaceae vegetation coverage in the analysis led to excessively high RPP values for the other taxa.When bamboo coverage was removed from the Poaceae family,the recalculated RPP values aligned closely with those reported in previous studies.The RPP values,ranked from highest to lowest,were as follows:Castanopsis(12.33±0.03)>Araliaceae(1.60±0.03)>Mallotus(1.53±0.26)>Pinus(1.47±0.03)>Rosaceae(1.07±0.02)>Poaceae(1±0)>Euphorbiaceae(0.44±0.03)>Anacardiaceae(0.26±0.03)>Theaceae(0.15±0).Notably,the RPP values for Mallotus,Araliaceae,Theaceae,and Euphorbiaceae represent the first estimates for China’s subtropical region.Differences between certain RPP estimates and those of previous studies may be attributed to factors such as species composition,vegetation structure,and model selection.The findings of this study highlight that due to the widespread distribution of artificial bamboo forests in China’s subtropical regions,future RPP studies should carefully consider the influence of Poaceae.This consideration is essential for improving the accuracy of the application of fossil pollen for quantitative paleo-vegetation reconstruction in these regions. 展开更多
关键词 Pollen-vegetation relationships Relative pollen productivity SUBTROPICAL Bamboo forest ERV model
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Inter-and intra-specific phenotypic variation of ecological stoichiometric traits in a mixed-oak secondary forest in China 被引量:2
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作者 Yueyao Feng Xuan Li +4 位作者 Biyao Zhou Rong Hu Huanchao Zhang Jiading Yang Yanming Fang 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2333-2347,共15页
Ecological stoichiometry provides a framework for the balance and flow of elements between organisms and ecosystems.Elemental phenotypes have an important influence on the environmental adaptation and ecological evolu... Ecological stoichiometry provides a framework for the balance and flow of elements between organisms and ecosystems.Elemental phenotypes have an important influence on the environmental adaptation and ecological evolution of plants.There have been few reports on inter-and intra-specific phenotypic variations of ecological stoichiometric traits for congeneric species in a mixed forest although such variations are well-documented at the species level at global,regional and local scales.In this study,total carbon(TC),nitrogen(TN),phosphorus(TP)and potassium(TK)were measured in leaves and the elemental phenotypes were statistically analyzed in four species of oaks—Quercus fabri,Q.serrata var.glandulifera,Q.acutissima and Q.variabilis—in a mixed-oak secondary forest in Yushan,Jiangsu,China.The average element concentrations in the four oak species were not relatively higher than previously reported for oaks from world and Chinese flora.Ecological stoichiometry traits were correlated with tree height and diameter at breast height,indicating that phosphorous and potassium were positively correlated with tree size,while carbon was negatively correlated,especially the relationship between oak growth and total carbon or total phosphorus was obvious,and the study concluded that this was because plant growth depended on phosphorus storage and had opposite effects on leaf carbon accumulation.Based on tree plasticity index and the coefficient of variation,there was medium variation in element concentrations.The plasticity index of total carbon levels was the lowest,and that of potassium the highest.Principal component analysis and cluster analysis showed that the intra-specific variation among the four oak species was higher than inter-specific variation.From the perspective of nutrient supply and ecological adaptation,this study creates a foundation for the management of secondary oak forest stands. 展开更多
关键词 Ecological stoichiometry QUERCUS Elemental phenotype intra-specific variation Inter-specific variation Ecological evolution Nutrient supply
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DYNAMICAL BEHAVIOR OF AN INNOVATION DIFFUSION MODEL WITH INTRA-SPECIFIC COMPETITION BETWEEN COMPETING ADOPTERS 被引量:1
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作者 Rakesh KUMAR Anuj Kumar SHARMA Govind Prasad SAHU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第1期364-386,共23页
In this paper,we proposed an innovation diffusion model with three compartments to investigate the diffusion of an innovation(product)in a particular region.The model exhibits two equilibria,namely,the adopter-free an... In this paper,we proposed an innovation diffusion model with three compartments to investigate the diffusion of an innovation(product)in a particular region.The model exhibits two equilibria,namely,the adopter-free and an interior equilibrium.The existence and local stability of the adopter-free and interior equilibria are explored in terms of the effective Basic Influence Number(BIN)R_(A).It is investigated that the adopter free steady-state is stable if R_(A)<1.By consideringτ(the adoption experience of the adopters)as the bifurcation parameter,we have been able to obtain the critical value ofτresponsible for the periodic solutions due to Hopf bifurcation.The direction and stability analysis of bifurcating periodic solutions has been performed by using the arguments of normal form theory and the center manifold theorem.Exhaustive numerical simulations in the support of analytical results have been presented. 展开更多
关键词 intra-specific competition basic influence number local stability HOPF-BIFURCATION normal form theory center manifold theorem
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Construction of a Maritime Knowledge Graph Using GraphRAG for Entity and Relationship Extraction from Maritime Documents 被引量:3
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作者 Yi Han Tao Yang +2 位作者 Meng Yuan Pinghua Hu Chen Li 《Journal of Computer and Communications》 2025年第2期68-93,共26页
In the international shipping industry, digital intelligence transformation has become essential, with both governments and enterprises actively working to integrate diverse datasets. The domain of maritime and shippi... In the international shipping industry, digital intelligence transformation has become essential, with both governments and enterprises actively working to integrate diverse datasets. The domain of maritime and shipping is characterized by a vast array of document types, filled with complex, large-scale, and often chaotic knowledge and relationships. Effectively managing these documents is crucial for developing a Large Language Model (LLM) in the maritime domain, enabling practitioners to access and leverage valuable information. A Knowledge Graph (KG) offers a state-of-the-art solution for enhancing knowledge retrieval, providing more accurate responses and enabling context-aware reasoning. This paper presents a framework for utilizing maritime and shipping documents to construct a knowledge graph using GraphRAG, a hybrid tool combining graph-based retrieval and generation capabilities. The extraction of entities and relationships from these documents and the KG construction process are detailed. Furthermore, the KG is integrated with an LLM to develop a Q&A system, demonstrating that the system significantly improves answer accuracy compared to traditional LLMs. Additionally, the KG construction process is up to 50% faster than conventional LLM-based approaches, underscoring the efficiency of our method. This study provides a promising approach to digital intelligence in shipping, advancing knowledge accessibility and decision-making. 展开更多
关键词 Maritime Knowledge Graph GraphRAG Entity and relationship Extraction Document Management
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Relationship between the use of smart medical services and mental health status
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作者 Elif Sarac 《World Journal of Psychiatry》 SCIE 2025年第1期21-25,共5页
In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the ... In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the potential to positively influence mental health by providing monitoring,insights,and inter-ventions.However,they also come with challenges that need to be addressed.Understanding the primary purpose for which individuals use these smart tech-nologies is essential to tailoring them to specific mental health needs and prefe-rences. 展开更多
关键词 Smart devices Medical service USAGE PEOPLE relationship Mental health status
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Intentional self-regulation and peer relationship in the teacher-student relationship for learning engagement: A moderation–mediation analysis
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作者 Mengjun Zhu Xing’an Yao Mansor Bin Abu Talib 《Journal of Psychology in Africa》 2025年第1期83-90,共8页
This study investigated the role of intentional self-regulation and the moderating role of peer relationship in the relationship between teacher-student relationship and learning engagement.The study sample comprised ... This study investigated the role of intentional self-regulation and the moderating role of peer relationship in the relationship between teacher-student relationship and learning engagement.The study sample comprised 540 Chinese senior secondary school students between the ages of 15–18(51.67%boys;Mage=16.56 years;SDage=0.90).They completed surveys on the Teacher-Student Relationship Scale,the Selection,Optimization,and Compensation(SOC)Scale,the Peer Relationship Scale for Children and Adolescents,and the Learning Engagement Scale.The results following regression analysis showed that teacher-student relationship predicted higher learning engagement among senior secondary school students.Intentional self-regulation partially mediated the link between teacher-student relationship and learning engagement for higher learning engagement.Peer relationship moderated the relationships between teacher-student relationship and learning engagement and moderated the relationship between teacher-student relationship and intentional self-regulation for higher learning engagement.Thesefindings imply learning engagement can be enhanced by optimizing teacher-student relationship and strengthening intentional self-regulation interventions. 展开更多
关键词 teacher-student relationship intentional self-regulation peer relationship learning engagement
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Space cannot substitute for time in the study of the ecosystem services-human wellbeing relationship
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作者 Lumeng Liu Jianguo Wu 《Geography and Sustainability》 2025年第2期57-68,共12页
The relationship between ecosystem services(ES)and human well-being(HWB)is fundamental to the science and practice of sustainability.However,studies have shown conflicting results,which has been attributed to the infl... The relationship between ecosystem services(ES)and human well-being(HWB)is fundamental to the science and practice of sustainability.However,studies have shown conflicting results,which has been attributed to the influences of indicators,contexts,and scales.Yet,another potential factor,which has been overlooked,may be the mixed use of spatial and temporal approaches.Using twelve ES and seven well-being indicators and multiple statistical methods,we quantified and compared the spatial and temporal ES–HWB relationships for Inner Mongolia,China.The spatial and temporal relationships differed in both correlation direction and strength.Most relationships of economic and employment-related indicators with food provisioning and supporting services were temporally positive but spatially nonsignificant or negative.Some relationships of economic and employmentrelated indicators with water retention,sandstorm prevention,and wind erosion were temporally negative but spatially complex.However,the spatial and temporal ES–HWB relationships could also be similar in some cases.We conclude that although both the spatial and temporal approaches have merits,space generally cannot substitute for time in the study of ES–HWB relationship.Our study helps reconcile the seemingly conflicting findings in the literature,and suggests that future studies should explicitly distinguish between the spatial and temporal ES–HWB relationships. 展开更多
关键词 Ecosystem services Objective human well-being Space-for-time substitution Spatial relationship Temporal relationship
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Teacher-student relationship quality effects on school students’bullying victimization:A serial mediation model by student-student relationship and student engagement
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作者 Yuan Yuan Yanfei Yang 《Journal of Psychology in Africa》 2025年第4期541-548,共8页
This study examined the impact of teacher-student relationship quality on students’risk of bullying victimiza-tion and the mediating roles of student-student relationships and student engagement in this relationship.... This study examined the impact of teacher-student relationship quality on students’risk of bullying victimiza-tion and the mediating roles of student-student relationships and student engagement in this relationship.A total of 656 Chinese junior high school students(females=361,mean age=13.75,SD=0.98)completed validated measures of teacher-student relationship quality,student-student relationship quality,student engagement,and bullying victimization.Regression analysis results indicated that higher teacher-student relationship quality predicted a lower risk of student bullying victimization.Serial mediating effect testing of the student-student relationship quality and student engagement revealed that these factors fully mediated the relationship between teacher-student relationship quality and bullying victimization,resulting in a lower risk of bullying victimization.The results showed that student-student relationship quality had a more substantial mediating effect than student engagement.Thefindings support the Socio-Ecological Framework,suggesting that within the Microsystem,interactions between individuals and their immediate environments significantly impact their behavior.Specifically,thesefindings suggest that good teacher-student relationships can enhance the quality of student-student relationships and student engagement,thereby preventing and reducing the occurrence of bullying victimization. 展开更多
关键词 teacher-student relationship quality bullying victimization student-student relationship quality student engagement junior middle school students
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Research on the Relationship Between Islam and Chinese Culture
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作者 Alimtohte Shiho 《Cultural and Religious Studies》 2025年第1期1-11,共11页
Since China’s reform and development,under the influence of the global religious and cultural boom,it has also focused on studying Islamic culture and related fields,resulting in many important representative works.T... Since China’s reform and development,under the influence of the global religious and cultural boom,it has also focused on studying Islamic culture and related fields,resulting in many important representative works.The main characteristic of writing books in this area is to use popular knowledge materials that are suitable for various sectors of society.There are also works exploring the historical evolution of Islamic culture in China,which involve the relationship between Islamic culture and traditional Chinese culture.Before the 1980s,there were no significant achievements in publishing papers.However,since the 1990s,there has been a noticeable increase in papers related to Islamic culture and related fields,with new advances in research areas and methods.There are both articles that explore the attributes and characteristics of Islamic culture from the perspectives of world history and culture,as well as many articles that explore various specific aspects of Islamic culture from the perspective of specific topics.In this article,the author collects academic achievements in the study of Islamic culture in China and introduces them to the academic community,letting them know about China's research on world Islamic culture. 展开更多
关键词 China Islamic world Islamic Culture RESEARCH relationship
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Relationship of diabetes mellitus with prognostic factors in breast cancer
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作者 Songul Peltek Ozer Fatih Keyif +2 位作者 Ferdi Bolat Bahri Ozer Gulali Aktas 《World Journal of Experimental Medicine》 2025年第3期127-133,共7页
BACKGROUND Hyperglycemia secondary to diabetes can lead to organ failure unless properly controlled,and it is associated with numerous health issues,particularly metabolic problems.Breast cancer is one of the most com... BACKGROUND Hyperglycemia secondary to diabetes can lead to organ failure unless properly controlled,and it is associated with numerous health issues,particularly metabolic problems.Breast cancer is one of the most common malignancies in females worldwide and represents a major health concern due to its morbidity and mortality.The progression of the disease and the response to treatment depend on numerous variables,including both tumor biology and patient-related factors.Key prognostic indicators include age,tumor size,lymph node involvement,histological type,hormone receptor status,and expression of biomarkers such as HER2.AIM To investigate the relationship between preoperative blood glucose levels and cancer prognostic factors in patients diagnosed with breast cancer.METHODS In this study patients diagnosed with breast cancer were classified into two groups:Those with blood glucose levels<125 mg/dL and those with levels>125 mg/dL.Estrogen and progesterone receptor positivity,Ki-67 percentage,Cerb2 positivity,number of positive lymph nodes,and presence of lymphovascular invasion were examined histopathologically.RESULTS The study included 246 patients with breast cancer:196 were in the normal glucose group and 50 were in the elevated glucose group.In the normal glucose group,68%of the tumors were left-sided and 32%were right-sided,while all tumors in the elevated glucose group were left-sided.This difference was statistically significant(P<0.001).Tumor size,Ki-67,and the number of positive lymph nodes were not associated with blood glucose in patients with breast cancer(P>0.05 for all).However,blood glucose was correlated with age in this population.Correlation analyses revealed that blood glucose was positively correlated with age(r=0.23,P<0.001).Additionally,Ki-67 was correlated with tumor size(r=0.14,P=0.03)and age(r=-0.18,P=0.005).CONCLUSION Our study highlighted the complex interplay between metabolic factors,such as fasting glucose levels,and breast cancer characteristics.Elevated glucose levels were associated with older age.The significant association between tumor laterality and glucose levels underscores the need for further investigation into the collective influence of metabolic and anatomical factors on breast cancer development and progression. 展开更多
关键词 Diabetes mellitus Breast cancer HYPERGLYCEMIA PROGNOSIS relationship
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A rapid analysis method to discover antioxidant active components and mechanisms in soybean:untargeted metabolomics combined with network pharmacology and spectrum-effect relationship-component knockout-identification techniques
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作者 Xuqiang Liu Xinjing Meng +3 位作者 Dongqi Liu Junshang Liu Mengqi Lan Wenyi Kang 《Food Science and Human Wellness》 2025年第9期3753-3763,共11页
Soybean is widely used in diets,and numerous reports have highlighted its antioxidant properties.However,constructing a methodology for rapid identifying and predicting a series of antioxidant active ingredients in So... Soybean is widely used in diets,and numerous reports have highlighted its antioxidant properties.However,constructing a methodology for rapid identifying and predicting a series of antioxidant active ingredients in Soybean presents certain challenges.Therefore,we introduced the spectrum-effect relationship-ingredient knockout identification technique to identify a series of antioxidant active ingredients in soybean.By combining untargeted metabolomics with network pharmacology,we predicted the antioxidant active ingredients and their target sites.We successfully identified 4 antioxidant active compounds(daidzein,genistein,daidzein,and glycitin)and 10 corresponding antioxidant targets(epidermal growth factor receptor(EGFR),estrogen receptor 1(ESR1),steroid receptor coactivator(SRC),tumor necrosis factor(TNF),kinase insert domain receptor(KDR),AKT serine/threonine kinase 1(AKT1),growth factor receptor bound protein 2(GRB2),signal transducer and activator of transcription1(STAT1),mitogen-activated protein kinase 8(MAPK8),B-cell lymphoma-2(BCL2))by our analysis.The validation results from cell experiments revealed that glycitin exhibited the best antioxidant activity and significantly influenced the expression of EGFR and the proteins associated with nuclear factor erythroid 2-related factor 2/NAD(P)H quinone dehydrogenase 1(NRF2/NQO1)signaling pathways.These findings were consistent with the predicted outcomes and were further confirmed in a zebrafish model.It suggests that glycitin may exert antioxidant effects by regulating the expression of EGFR,NRF2,and NQO1 proteins.The results demonstrate that a rapid analytical method for determining antioxidant activity was established. 展开更多
关键词 SOYBEAN ANTIOXIDANT Metabolomics Network pharmacology Spectrum-Effect relationship
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Application of artificial intelligence to quantitative structure-retention relationship calculations in chromatography
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作者 Jingru Xie Si Chen +1 位作者 Liang Zhao Xin Dong 《Journal of Pharmaceutical Analysis》 2025年第1期4-18,共15页
Quantitative structure-retention relationship(QSRR)is an important tool in chromatography.QSRR examines the correlation between molecular structures and their retention behaviors during chromatographic separation.This... Quantitative structure-retention relationship(QSRR)is an important tool in chromatography.QSRR examines the correlation between molecular structures and their retention behaviors during chromatographic separation.This approach involves developing models for predicting the retention time(RT)of analytes,thereby accelerating method development and facilitating compound identification.In addition,QSRR can be used to study compound retention mechanisms and support drug screening efforts.This review provides a comprehensive analysis of QSRR workflows and applications,with a special focus on the role of artificial intelligence-an area not thoroughly explored in previous reviews.Moreover,we discuss current limitations in RT prediction and propose promising solutions.Overall,this review offers a fresh perspective on future QSRR research,encouraging the development of innovative strategies that enable the diverse applications of QSRR models in chromatographic analysis. 展开更多
关键词 Quantitative structure-retention relationship CHROMATOGRAPHY ACCURACY Machine learning
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The Influence of Leisure-Time Physical Activity and Peer Relationships on Cyberbullying among Adolescents:A One-Year Longitudinal Investigation
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作者 Jingtao Wu Yanhong Shao +1 位作者 Wanli Zang Jun Hu 《International Journal of Mental Health Promotion》 2025年第5期717-735,共19页
Background With the rapid growth of internet usage,adolescent cyberbullying has become a pressing issue.This study examines the longitudinal impact of leisure-time physical activity and peer relationships on cyberbull... Background With the rapid growth of internet usage,adolescent cyberbullying has become a pressing issue.This study examines the longitudinal impact of leisure-time physical activity and peer relationships on cyberbullying over a one-year period,drawing on the Stage-Environment Fit Theory and the Interpersonal Relationship Theory.Methods A three-wave longitudinal study was conducted over one year,involving 896 middle school students from five schools in Sichuan,Jiangsu,and Guangdong,China,selected to ensure regional diversity.Participants were recruited using stratified random sampling,and data were collected at four-month intervals.Leisure-time physical activity,peer relationships,and cyberbullying behaviors were assessed using validated scales.Data were analyzed using latent growth modeling(LGM)and structural equation modeling(SEM)to examine longitudinal effects and mediation relationships.Results(1)Leisure-time physical activity,peer relationships,and cyberbullying behaviors remained relatively stable over time.(2)Both leisure-time physical activity and peer relationships significantly reduced future cyberbullying incidents,with physical activity also enhancing subsequent peer relationships.(3)Peer relationships partially mediated the effect of leisure-time physical activity on cyberbullying,indicating that improved peer interactions contributed to a reduction in cyberbullying behaviors.Conclusion This study found that leisure-time sports activities and peer relationships are important factors affecting cyberbullying,and peer relationships play a partial mediating role in it.The results provide empirical support for understanding the formation mechanism and influencing factors of cyberbullying. 展开更多
关键词 LEISURE-TIME physical activity CYBERBULLYING peer relationships adolescents
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Enhancing yield strength and quantifying relationship with microstructure in magnesium alloys through work hardening
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作者 Xiaoyu Wang Wenzhen Chen +5 位作者 Yang Yu Wenjie Wu Wenke Wang Daqing Fang Wencong Zhang Jun Sun 《Journal of Magnesium and Alloys》 2025年第6期2581-2590,共10页
This paper explored how the work hardening process enhances the yield strength(YS)of magnesium alloy and established a novel quantitative relationship between microstructure and YS.The YS of an extruded Mg–Nd–Zn–Zr... This paper explored how the work hardening process enhances the yield strength(YS)of magnesium alloy and established a novel quantitative relationship between microstructure and YS.The YS of an extruded Mg–Nd–Zn–Zr alloy was nearly tripled by rotary swaging at 200℃,attributing to dislocation accumulation,grain fragmentation,and basal texture formation.A modified Hall–Petch relationship(GM–HP)was established by introducing the equivalent orientation factor and dislocation density to accurately quantify the YS and the contribution of each strengthening mechanism.The contributions of dislocation hardening and grain boundary strengthening were multiplied by the strong basal texture.This paper offered valuable insights and guidance for designing and optimizing high-strength wrought magnesium alloys and their plastic processing methods. 展开更多
关键词 Work hardening TEXTURE DISLOCATION GM-HP relationship
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Determining the Relationship Between Change of Direction Speed and Agility in Team Sport Athletes:Meta-Analysis
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作者 Rafael Carvajal-Espinoza Scott Talpey Walter Salazar-Rojas 《Journal of Science in Sport and Exercise》 2025年第3期253-264,共12页
Background Agility and change of direction speed(COD)are essential skills in sports,their development being the focus of training and research.While these terms have been used interchangeably,it is crucial to distingu... Background Agility and change of direction speed(COD)are essential skills in sports,their development being the focus of training and research.While these terms have been used interchangeably,it is crucial to distinguish between agility and COD,as the latter involves a sudden change in direction without the presence of external stimuli.Objective This meta-analysis aims to summarize studies that have included COD and agility tests and explore the potential relationship between these two physical qualities.Method Following the PRISMA guidelines,a meta-analysis was conducted using studies published between 2005 and 2021.All studies identified for inclusion were peer-reviewed and published in English and Spanish,using an athlete population as participants.For all analyses,a significance level was set at P<0.05.Results The meta-analysis,which included 21 studies with 945 participants from various team sports,found a moderate correlation(r=0.46)between agility and COD.This study considers moderator variables such as Age,Sex,Sport,Test Pattern,Test Combination,and Agility Stimulus.Conclusion The results of this study revealed that while COD and agility have commonalities,these two constructs represent distinct different qualities.Younger participants show a stronger correlation between the two,emphasizing age-related differences in physical development.Coaches should consider these findings in designing training programs and assessments,tailoring approaches based on the specific demands of each skill.The study contributes valuable insights into the nuanced relationship between agility and COD in team sports. 展开更多
关键词 AGILITY Change of direction Performance relationship Team sports Correlation
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The Change and Challenge of Teacher-Student Relationship in the Era of Artificial Intelligence:Teaching Interaction and Emotional Connection
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作者 Jiaqi Liu Ling Peng 《Journal of Contemporary Educational Research》 2025年第6期87-93,共7页
With the rapid development of artificial intelligence(AI)technology,its application in higher education has gradually shifted from traditional teaching aids to deeper levels of interactive learning and emotional conne... With the rapid development of artificial intelligence(AI)technology,its application in higher education has gradually shifted from traditional teaching aids to deeper levels of interactive learning and emotional connection support.AI can enhance teaching efficiency,personalized learning,and real-time feedback;however,in areas such as emotional communication and teacher-student interaction,AI still cannot fully replace the role of teachers.This study aims to explore the transformation of teacher-student relationships in the era of AI,analyze the impact of AI technology on teaching interaction,emotional support,and teacher-student trust,and propose strategies to address these challenges.The research findings indicate that while AI has significant advantages in improving educational efficiency,it has limitations in interpersonal emotional support and the transformation of the teacher’s role.To ensure the comprehensiveness and humanization of education,educators should strengthen emotional care and improve students’emotional literacy in the use of AI,and implement transparent data management and privacy protection measures to enhance teacher-student trust.The study also suggests that by enhancing teacher-student trust,strengthening emotional support,and increasing transparency,educators can effectively address the challenges of teacher-student relationships in the AI era.This research provides theoretical support and practical guidance for the integration of AI technology with educational humanistic care,promoting more comprehensive,personalized,and humane educational development. 展开更多
关键词 Artificial intelligence Teacher-student relationship Emotional support Teaching interaction
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The Instantiation Significance of Digital Sculpture:Analysis of the Associated Relationship between Art and Technology
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作者 Shuang Ben 《Journal of Contemporary Educational Research》 2025年第7期363-368,共6页
Digital sculpture is the product of the cross-integration of art and technology,and its development is accompanied by the two-way interaction between technological innovation and artistic concepts.Based on this,this p... Digital sculpture is the product of the cross-integration of art and technology,and its development is accompanied by the two-way interaction between technological innovation and artistic concepts.Based on this,this paper mainly analyzes the remolding of artistic creation logic by technical tools and the expansion of technical application boundary by artistic expression,and further reveals the dynamic balance relationship between the two in symbiosis,hoping to help understand the accompanying mechanism of art and technology in the digital age. 展开更多
关键词 Digital sculpture INSTANTIATION Art and technology Associated relationship
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A Review of the Research on Supply Chain Relationships and Corporate Finance
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作者 Zhifeng Chen 《Proceedings of Business and Economic Studies》 2025年第5期62-68,共7页
The interaction between supply chain relationships and corporate finance has become a focal issue in academic and practical circles,especially under the dual drivers of globalization and marketization.This paper syste... The interaction between supply chain relationships and corporate finance has become a focal issue in academic and practical circles,especially under the dual drivers of globalization and marketization.This paper systematically reviews existing research on this topic,covering theoretical foundations from perspectives such as agency theory,stakeholder theory,and co-opetition game theory,which explain the nature of customer-supplier relationships.It also combs through empirical studies from four core angles:competition-cooperation,signal transmission,spillover effects,and information transfer,summarizing findings on how supply chain relationships impact corporate investment,financing,operations,and performance,as well as existing controversies.The aim is to clarify the research context,identify theoretical and empirical gaps,and provide theoretical support and direction for deepening future research on supply chain and corporate finance. 展开更多
关键词 Supply chain relationships Corporate finance Competition-cooperation Signal transmission Spillover effects
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