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Comparative transcriptome analysis between rhesus macaques(Macaca mulatta) and crab-eating macaques(M. fascicularis) 被引量:1
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作者 Yu-Xiang Mao Yamei Li +6 位作者 Zikun Yang Ning Xu Shilong Zhang Xuankai Wang Xiangyu Yang Qiang Sun Yafei Mao 《Zoological Research》 SCIE CSCD 2024年第2期299-310,共12页
Understanding gene expression variations between species is pivotal for deciphering the evolutionary diversity in phenotypes. Rhesus macaques(Macaca mulatta, MMU)and crab-eating macaques(M. fascicularis, MFA) serve as... Understanding gene expression variations between species is pivotal for deciphering the evolutionary diversity in phenotypes. Rhesus macaques(Macaca mulatta, MMU)and crab-eating macaques(M. fascicularis, MFA) serve as crucial nonhuman primate biomedical models with different phenotypes. To date, however, large-scale comparative transcriptome research between these two species has not yet been fully explored. Here, we conducted systematic comparisons utilizing newly sequenced RNA-seq data from84 samples(41 MFA samples and 43 MMU samples)encompassing 14 common tissues. Our findings revealed a small fraction of genes(3.7%) with differential expression between the two species, as well as 36.5% of genes with tissue-specific expression in both macaques. Comparison of gene expression between macaques and humans indicated that 22.6% of orthologous genes displayed differential expression in at least two tissues. Moreover,19.41% of genes that overlapped with macaque-specific structural variants showed differential expression between humans and macaques. Of these, the FAM220A gene exhibited elevated expression in humans compared to macaques due to lineage-specific duplication. In summary,this study presents a large-scale transcriptomic comparison between MMU and MFA and between macaques and humans. The discovery of gene expression variations not only enhances the biomedical utility of macaque models but also contributes to the wider field of primate genomics. 展开更多
关键词 Crab-eating macaques Rhesus macaques comparative transcriptomics Biomedical models Nonhuman primates RNA-SEQ Duplicated genes
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Descriptive and Comparative Histology of the Urinary System of the Hematophagous Bats Desmodus rotundus and Diphylla ecaudata
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作者 María Guadalupe Ramírez-Muñoz Samantha Jardon-Xicotencatl +2 位作者 José Ignacio Olave-Leyva Armando Zepeda-Bastida Juan Ocampo-López 《Open Journal of Veterinary Medicine》 CAS 2024年第7期180-191,共12页
Desmodus rotundus and Diphylla ecaudata, both of which are mammals of the order Chiroptera, Desmodontidae family, their diet consisting exclusively of blood. D. rotundus is the main vector and transmitter of the rabie... Desmodus rotundus and Diphylla ecaudata, both of which are mammals of the order Chiroptera, Desmodontidae family, their diet consisting exclusively of blood. D. rotundus is the main vector and transmitter of the rabies virus, which affects human beings as well as several livestock species so the study of this bat species is of high importance within the fields of animal agriculture and public health. The present study describes and compares the histologic characteristics of the urinary system of two hematophagous bat species. A total of 5 bats from each species were captured in the municipalities of Progreso de Obregón, Hidalgo (D. rotundus), and Huayacocotla, Veracruz (D. ecaudata). Organs belonging to the urinary system were extracted: kidneys, ureters, urinary bladder, and urethra;samples were fixed using 10% formalin and processed by the paraffin embedding technique, obtaining sections of 5 µm thickness, which in turn were stained using hematoxylin-eosin (H-E) and Gomori trichrome (GT) stains. From the obtained histologic preparations, a descriptive and comparative analysis of the structural organography of the urinary system of both species was made, and no noteworthy histological differences between samples were noted. The present research is intended to provide a framework for future studies of these species’ currently understudied microscopic anatomy. 展开更多
关键词 Microscopic Anatomy Vampire Bats KIDNEYS comparative Morphology
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Rice-wheat comparative genomics:Gains and gaps
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作者 Akila Wijerathna-Yapa Ruchi Bishnoi +11 位作者 Buddhini Ranawaka Manu Maya Magar Hafeez Ur Rehman Swati G.Bharad Michal T.Lorenc Vinita Ramtekey Sasha Gohar Charu Lata Md.Harun-Or-Rashid Maryam Razzaq Muhammad Sajjad Bhoja R.Basnet 《The Crop Journal》 SCIE CSCD 2024年第3期656-669,共14页
Rice and wheat provide nearly 40%of human calorie and protein requirements.They share a common ancestor and belong to the Poaceae(grass)family.Characterizing their genetic homology is crucial for developing new cultiv... Rice and wheat provide nearly 40%of human calorie and protein requirements.They share a common ancestor and belong to the Poaceae(grass)family.Characterizing their genetic homology is crucial for developing new cultivars with enhanced traits.Several wheat genes and gene families have been characterized based on their rice orthologs.Rice–wheat orthology can identify genetic regions that regulate similar traits in both crops.Rice–wheat comparative genomics can identify candidate wheat genes in a genomic region identified by association or QTL mapping,deduce their putative functions and biochemical pathways,and develop molecular markers for marker-assisted breeding.A knowledge of gene homology facilitates the transfer between crops of genes or genomic regions associated with desirable traits by genetic engineering,gene editing,or wide crossing. 展开更多
关键词 comparative genomics ORTHOLOGS GENES SYNTENY Genetic engineering Molecular breeding
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Comparative and Phylogenetic Analysis of the Complete Chloroplast Genomes of 19 Species in Rosaceae Family
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作者 Riwa Mahai Rongpeng Liu +3 位作者 Xiaolang Du Zejing Mu Xiaoyun Wang Jun Yuan 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第6期1203-1219,共17页
Rosaceae represents a vast and complex group of species,with its classification being intricate and contentious.The taxonomic placement of many species within this family has been a subject of ongoing debate.The study ... Rosaceae represents a vast and complex group of species,with its classification being intricate and contentious.The taxonomic placement of many species within this family has been a subject of ongoing debate.The study utilized the Illumina platform to sequence 19 plant species from 10 genera in the Rosaceae.The cp genomes,vary-ing in size from 153,366 to 159,895 bp,followed the typical quadripartite organization consisting of a large single-copy(LSC)region(84,545 to 87,883 bp),a small single-copy(SSC)region(18,174 to 19,259 bp),and a pair of inverted repeat(IR)regions(25,310 to 26,396 bp).These genomes contained 132–138 annotated genes,including 87 to 93 protein-coding genes(PCGs),37 tRNA genes,and 8 rRNA genes using MISA software,52 to 121 simple sequence repeat(SSR)loci were identified.D.arbuscular contained the least of SSRs and did not have hexanotides,A.lineata contained the richest SSRs.Long terminal repeats(LTRs)were primarily composed of palindromic and forward repeat sequences,meanwhile,The richest LTRs were found in Argentina lineata.Except for Argentina lineata,Fragariastrum eriocarpum,and Prunus trichostoma,which varied in gene type and position on both sides of the boundary,the remaining species were found to be mostly conserved according to IR boundary analysis.The examination of the Ka/Ks ratio revealed that only the infA gene had a value greater than 1,indicating that this gene was primarily subjected to positive selection during evolution.Additionally,9 hotspots of variation were identified in the LSC and SSC regions.Phylogenetic analysis confirmed the scientific validity of the genus Prunus L.sensu lato(s.l.)within the Rosaceae family.The separation of the three genera Argentina Hill,Fragariastrum Heist.ex Fabr.and Dasiphora Raf.from Potentilla L.may be a more scientific classification.These results offer fresh perspectives on the taxonomy of the Rosaceae. 展开更多
关键词 ROSACEAE chloroplast genomes comparative genomes PHYLOGENY
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Exploring Nominalization in English Abstracts of Applied Linguistics Research Articles:A Comparative Study Between Chinese and International Journals
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作者 Gong Yingrui Zhao Yibu 《Contemporary Social Sciences》 2024年第4期122-142,共21页
Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of ... Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of abstracts from a macro perspective and often employed either outdated texts,such as those over a decade old,or papers written by authors with lower English academic writing proficiency as research material.In this study,we analyzed forty abstracts from leading journals in applied linguistics,evenly split between Chinese and international journals.It revealed that the use of nominalization in abstracts by Chinese and international scholars showed similarities due to the universal academic requirement for conciseness.However,due to cultural and educational differences,each group differed in their respective language choices and nominalization usage.By analyzing the application of nominalization in different cultural contexts,the results of our study offered practical suggestions for crafting abstracts that effectively convey information,thereby,contributing to the broader academic community. 展开更多
关键词 NOMINALIZATION ABSTRACTS comparative study applied linguistics
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The relationship between compartment models and their stochastic counterparts:A comparative study with examples of the COVID-19 epidemic modeling
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作者 Ziyu Zhao Yi Zhou +6 位作者 Jinxing Guan Yan Yan Jing Zhao Zhihang Peng Feng Chen Yang Zhao Fang Shao 《Journal of Biomedical Research》 CAS CSCD 2024年第2期175-188,I0016-I0018,共17页
Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochast... Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochastic models is not well understood.The present study aimed to address this gap by conducting a comparative study using the susceptible,exposed,infectious,and recovered(SEIR)model and its extended CMs from the coronavirus disease 2019 modeling literature.We demonstrated the equivalence of the numerical solution of CMs using the Euler scheme and their stochastic counterparts through theoretical analysis and simulations.Based on this equivalence,we proposed an efficient model calibration method that could replicate the exact solution of CMs in the corresponding stochastic models through parameter adjustment.The advancement in calibration techniques enhanced the accuracy of stochastic modeling in capturing the dynamics of epidemics.However,it should be noted that discrete-time stochastic models cannot perfectly reproduce the exact solution of continuous-time CMs.Additionally,we proposed a new stochastic compartment and agent mixed model as an alternative to agent-based models for large-scale population simulations with a limited number of agents.This model offered a balance between computational efficiency and accuracy.The results of this research contributed to the comparison and unification of deterministic CMs and stochastic models in epidemic modeling.Furthermore,the results had implications for the development of hybrid models that integrated the strengths of both frameworks.Overall,the present study has provided valuable epidemic modeling techniques and their practical applications for understanding and controlling the spread of infectious diseases. 展开更多
关键词 compartment models agent-based models compartment-agent mixed models comparative study COVID-19
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Comparative efficacy of proximal femoral nail vs dynamic condylar screw in treating unstable intertrochanteric fractures
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作者 Ahmed Mohamed Yousif Mohamed Monzir Salih +2 位作者 Mohanad Abdulgadir Ayman E Abbas Duha Lutfi Turjuman 《World Journal of Orthopedics》 2024年第8期796-806,共11页
BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment ... BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment efficacy of dynamic condylar screws(DCS)and proximal femoral nails(PFN)for unstable intertrochanteric fractures.METHODS To find pertinent randomized controlled trials and retrospective observational studies comparing PFN with DCS for the management of unstable femoral intertrochanteric fractures,a thorough search was carried out.For research studies published between January 1996 and April 2024,PubMed,EMBASE,Scopus,Web of Science,Cochrane Library,and Google Scholar were all searched.The complete texts of the papers were retrieved,vetted,and independently examined by two investigators.Disputes were settled by consensus,and any disagreements that persisted were arbitrated by a third author.RESULTS This study included six articles,comprising a total of 173 patients.Compared to the DCS,the PFN had a shorter operation time[mean difference(MD):-41.7 min,95%confidence interval(95%CI):-63.04 to-20.35,P=0.0001],higher success rates with closed reduction techniques[risk ratio(RR):34.05,95%CI:11.12-104.31,P<0.00001],and required less intraoperative blood transfusion(MD:-1.4 units,95%CI:-1.80 to-1.00,P<0.00001).Additionally,the PFN showed shorter fracture union time(MD:-6.92 wk,95%CI:-10.27 to-3.57,P<0.0001)and a lower incidence of reoperation(RR:0.37,95%CI:0.17-0.82,P=0.01).However,there was no discernible variation regarding hospital stay,implant-related complications,and infections.CONCLUSION Compared to DCS,PFN offers shorter operative times,reduces the blood transfusions requirements,achieves higher closed reduction success,enables faster fracture healing,and lowers reoperation incidence. 展开更多
关键词 Intertrochanteric fracture UNSTABLE Dynamic condylar screw Proximal femoral nail META-ANALYSIS comparative study
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A Comparative Study on Factors Influencing Food Security in China and India
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作者 Shaowen YANG Meixue QIU 《Asian Agricultural Research》 2024年第2期12-15,共4页
This paper analyzes and compares the key factors influencing food security in two populous countries(China and India),and cate-gorizes them into three types:agricultural production,economic development and income leve... This paper analyzes and compares the key factors influencing food security in two populous countries(China and India),and cate-gorizes them into three types:agricultural production,economic development and income level,and income distribution.Using the prevalence of undernourishment as an indicator of food security,the paper empirically tests the degree of impact of various factors on food security in both countries using Tobit regression and Newey regression methods.The study finds that improving the level of economic development can significantly enhance food security in both countriesꎻreducing the Gini coefficient has a significant impact on India,but not on Chinaꎻincreasing the agricultural production per capita has a much greater effect on China than on India.Therefore,both countries should take measures that are both similar and different according to their national conditions to improve their food security level. 展开更多
关键词 Food security Influencing factors comparative study Econometric model
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Comparative Study of the Reliability and Complexity of Symmetrical and Asymmetrical Cryptosystems for the Protection of Academic Data in the Democratic Republic of Congo
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作者 Mugaruka Buduge Gulain Jeremie Ndikumagenge +2 位作者 Buhendwa Nyenyezi Justin Bulonza Masumbuko Alexis Katho Seba Jacques 《Journal of Information Security》 2024年第3期299-307,共9页
In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any mod... In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any modern company. A companys operational and historical data contains strategic and operational knowledge of ever-increasing added value. The emergence of a new paradigm: big data. Today, the value of the data scattered throughout this mother of knowledge is calculated in billions of dollars, depending on its size, scope and area of intervention. With the rise of computer networks and distributed systems, the threats to these sensitive resources have steadily increased, jeopardizing the existence of the company itself by drying up production and losing the interest of customers and suppliers. These threats range from sabotage to bankruptcy. For several decades now, most companies have been using encryption algorithms to protect and secure their information systems against the threats and dangers posed by the inherent vulnerabilities of their infrastructure and the current economic climate. This vulnerability requires companies to make the right choice of algorithms to implement in their management systems. For this reason, the present work aims to carry out a comparative study of the reliability and effectiveness of symmetrical and asymmetrical cryptosystems, in order to identify one or more suitable for securing academic data in the DRC. The analysis of the robustness of commonly used symmetric and asymmetric cryptosystems will be the subject of simulations in this article. 展开更多
关键词 comparative Study CRYPTOSYSTEMS Symmetric Encryption Asymmetric Encryption
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Research on the Comparison and Integration of Chinese and Western Music Cultures
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作者 LEI Shuwen 《Cultural and Religious Studies》 2024年第1期32-35,共4页
This research undertakes a nuanced examination of the intersections and distinctions between these two diverse musical traditions.Employing a meticulous comparative analysis,the study scrutinizes fundamental musical e... This research undertakes a nuanced examination of the intersections and distinctions between these two diverse musical traditions.Employing a meticulous comparative analysis,the study scrutinizes fundamental musical elements such as scales,modes,and compositional styles,illuminating shared threads and distinctive attributes that characterize Chinese and Western music.Against the backdrop of contemporary global dynamics,the research investigates the ongoing integration of these musical cultures.It explores the impact of globalization and technological advancements,revealing instances of cross-cultural collaboration and the emergence of hybrid musical forms.Augmenting theoretical discussions with concrete case studies,the paper offers illuminating examples of how Chinese and Western musical elements interweave,contributing to the evolving landscape of global music.This research not only advances scholarly understanding but also contributes practical insights for musicians,educators,and enthusiasts navigating the evolving dynamics of cross-cultural musical expression.By elucidating the intricate relationship between Chinese and Western music cultures,the paper underscores the richness borne out of their interaction and the cultural synthesis that defines contemporary musical landscapes. 展开更多
关键词 comparative music analysis cross-cultural integration hybrid forms globalization influence
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Crack Width Comparison between ACI 318, Eurocode 2 and GB 50010 for Flexural RC Members
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作者 Guoqiang Liu Zhiyong Lu 《Open Journal of Civil Engineering》 2024年第1期116-126,共11页
Comparative research on different countries’ structural design codes holds great importance and can gain valuable insights: Awareness of Design Levels, Identifying Code Deficiencies and Optimizing Designs. The crack ... Comparative research on different countries’ structural design codes holds great importance and can gain valuable insights: Awareness of Design Levels, Identifying Code Deficiencies and Optimizing Designs. The crack width of concrete structure is an important design aspect of the civil design. The four highly recognized and widely used crack width theories are systematically summarized. Based on the mentioned theories and project practices, American code ACI system, Eurocode 2 1992-1 and Chinese code GB 50010 have different crack width control requirement and calculation methods. The crack width control method based on ACI system code has evolved from the Z-factor method to the steel bar spacing control method which is simple and easy to be adopted for engineering. Meanwhile, the ACI 224.1R also gives a direct crack width calculation method consistent with the steel bar spacing control method. The Eurocode 2 and GB 50010 based on the bond-slip & no-slip theory consider much more affecting factors than ACI for predicting crack width. Taking the crack width calculation of Tunnel 5 intake as an example, the crack widths of the structure are calculated according to ACI system code, Eurocode 2 and GB 50010 respectively, the results show that the crack width results in various codes are not much different. The EN 1992-1 and GB 50010 results are almost the same which are less than the ACI 224.1Rresults. 展开更多
关键词 Crack Width Structure Serviceability comparative Analysis
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Integrated Machine Learning and Deep Learning Models for Cardiovascular Disease Risk Prediction: A Comprehensive Comparative Study
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作者 Shadman Mahmood Khan Pathan Sakan Binte Imran 《Journal of Intelligent Learning Systems and Applications》 2024年第1期12-22,共11页
Cardiovascular Diseases (CVDs) pose a significant global health challenge, necessitating accurate risk prediction for effective preventive measures. This comprehensive comparative study explores the performance of tra... Cardiovascular Diseases (CVDs) pose a significant global health challenge, necessitating accurate risk prediction for effective preventive measures. This comprehensive comparative study explores the performance of traditional Machine Learning (ML) and Deep Learning (DL) models in predicting CVD risk, utilizing a meticulously curated dataset derived from health records. Rigorous preprocessing, including normalization and outlier removal, enhances model robustness. Diverse ML models (Logistic Regression, Random Forest, Support Vector Machine, K-Nearest Neighbor, Decision Tree, and Gradient Boosting) are compared with a Long Short-Term Memory (LSTM) neural network for DL. Evaluation metrics include accuracy, ROC AUC, computation time, and memory usage. Results identify the Gradient Boosting Classifier and LSTM as top performers, demonstrating high accuracy and ROC AUC scores. Comparative analyses highlight model strengths and limitations, contributing valuable insights for optimizing predictive strategies. This study advances predictive analytics for cardiovascular health, with implications for personalized medicine. The findings underscore the versatility of intelligent systems in addressing health challenges, emphasizing the broader applications of ML and DL in disease identification beyond cardiovascular health. 展开更多
关键词 Cardiovascular Disease Machine Learning Deep Learning Predictive Modeling Risk Assessment comparative Analysis Gradient Boosting LSTM
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Quantitative Comparative Study of the Performance of Lossless Compression Methods Based on a Text Data Model
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作者 Namogo Silué Sié Ouattara +1 位作者 Mouhamadou Dosso Alain Clément 《Open Journal of Applied Sciences》 2024年第7期1944-1962,共19页
Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their perform... Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding. 展开更多
关键词 Arithmetic Coding BWT Compression Ratio comparative Study Compression Techniques Shannon-Fano HUFFMAN Lossless Compression LZW PERFORMANCE REDUNDANCY RLE Text Data Tunstall
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Research on the Policy Evolution of Inclusive Education from an International Comparative Perspective
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作者 Leinuo Lu 《Journal of Contemporary Educational Research》 2024年第7期82-88,共7页
In recent years,thanks to the vigorous promotion by UNESCO,inclusive education has rapidly developed and spread worldwide.Governments across various nations have responded and implemented this approach,successively in... In recent years,thanks to the vigorous promotion by UNESCO,inclusive education has rapidly developed and spread worldwide.Governments across various nations have responded and implemented this approach,successively introducing laws and policies to ensure that children with special needs are better integrated into society and receive a comprehensive education.This paper begins by exploring the concept and connotation of inclusive education.Through an international comparative perspective,it conducts a comparative analysis of the policy evolution of inclusive education in China and the United Kingdom.Furthermore,it investigates the implications that advanced international policy experiences have for the development of inclusive education in China. 展开更多
关键词 Inclusive education International perspective Policy evolution comparative analysis
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Comparison of R and Excel in the Field of Data Analysis
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作者 Jue Wang 《Journal of Electronic Research and Application》 2024年第3期178-184,共7页
This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and i... This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and its powerful data management and analysis tools make it suitable for handling complex data analysis tasks.It is also highly customizable,allowing users to create custom functions and packages to meet their specific needs.Additionally,R language provides high reproducibility,making it easy to replicate and verify research results,and it has excellent collaboration capabilities,enabling multiple users to work on the same project simultaneously.These advantages make R language a more suitable choice for complex data analysis tasks,particularly in scientific research and business applications.The findings of this study will help people understand that R is not just a language that can handle more data than Excel and demonstrate that r is essential to the field of data analysis.At the same time,it will also help users and organizations make informed decisions regarding their data analysis needs and software preferences. 展开更多
关键词 EXCEL R language Data analysis Open source comparE Data management Advantages Disadvantages FUNCTION
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Precise calibration of zero-crossing temperature and drift of an ultralow expansion cavity with a clock transition spectrum 被引量:1
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作者 刘慧 姜坤良 +3 位作者 王进起 熊转贤 贺凌翔 吕宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期150-154,共5页
We report a clock transition spectrum approach, which is used to calibrate the zero-crossing temperature and frequency drift of an ultralow expansion(ULE) cavity with a Hertz level resolution. With this approach, th... We report a clock transition spectrum approach, which is used to calibrate the zero-crossing temperature and frequency drift of an ultralow expansion(ULE) cavity with a Hertz level resolution. With this approach, the linear and nonlinear drifts of the ULE cavity along a variety of controlled temperatures are clearly presented. When the controlled temperature of ULE cavity is tuned away from the zero-crossing temperature of the ULE cavity, the cavity shows larger and larger nonlinear drift. According to our theoretical analysis and experimental results, we investigate more details of the drift property of the ULE cavity around the zero-crossing temperature, which has seldom been explored before. We can definitely conclude that the zero-crossing temperature of our ULE cavity used in an ytterbium(Yb) lattice clock is around 31.7℃. 展开更多
关键词 clock transition spectra ULE cavity frequency drift zero-crossing temperature
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A Time-Domain Comparator Based Skipping-Window SAR ADC 被引量:1
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作者 Liangbo Xie Yan Ren +2 位作者 Mu Zhou Xiaolong Yang Zhengwen Huang 《Computers, Materials & Continua》 SCIE EI 2021年第11期1597-1609,共13页
This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to ... This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to bypass corresponding conversion steps when the input falls in a window indicated by a time-domain comparator,which can provide not only the polarity of the input,but also the amount information of the input.The timedomain comparator,which is based on the edge pursing principle,consists of delay cells,two NAND gates,two D-flip-flop register-based phase detectors and a counter.The digital characteristic of the comparator makes the design more flexible,and the comparator can achieve noise and power optimization automatically by simply adjusting the delay cell number.An energy efficient digital-to-analog converter(DAC)control scheme suitable for the skipping window technique is also developed to reduce the switching energy during SAR conversion.Together with the skipping-window technique,the linearity and the power consumption of the SAR ADC are improved.The impact of different window sizes on comparison cycles,DAC switching energy and the overall energy efficiency is analyzed.Simulation results show that the proposed skipping-window technique can improve the overall energy-efficiency of the SAR ADC,as well as the linearity,and the optimized window size for the overall energy efficiency will vary with the DAC switching energy. 展开更多
关键词 Skipping-window technique DAC switching scheme timedomain comparator low-power
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过敏原综合数据库COMPARE的介绍和应用 被引量:1
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作者 赵岚 高中山 《食品安全质量检测学报》 CAS 北大核心 2023年第2期43-49,共7页
随着分子生物学和基因组、蛋白组学技术的高速发展,越来越多的过敏原蛋白得到鉴定。为了提高对过敏原的研究及其在食品安全上的应用,很多机构都建立了不同类型的过敏原数据库。本文详细介绍了由美国健康与环境科学研究所(Health and Env... 随着分子生物学和基因组、蛋白组学技术的高速发展,越来越多的过敏原蛋白得到鉴定。为了提高对过敏原的研究及其在食品安全上的应用,很多机构都建立了不同类型的过敏原数据库。本文详细介绍了由美国健康与环境科学研究所(Health and Environmental Sciences Institute,HESI)协调组织国际合作团队建立的一个过敏原综合数据库COMPARE (COMprehensive Protein Allergen REsource),该数据库通过高通量序列分选算法结合专家人工审核方法,从各个公共蛋白质数据库、其他过敏原数据库以及相关文献中筛选过敏原,每年更新一次。此外还开发了基于FASTA算法的序列比对工具COMPASS (COMPare Analysis of Sequences with Software),允许用户进行实时序列比对。该数据库已广泛应用于新过敏原蛋白的鉴定以及蛋白质潜在致敏性的评价,对于食品安全管理和保障有重要参考价值。本文通过对COMPARE数据库的全面介绍,旨在提高该数据库在我国的应用价值,推动过敏原分子生物信息学的研究以及食品安全的发展。 展开更多
关键词 过敏原 数据库 comparE 生物信息学 序列比对 交叉反应 食品安全
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THE DESIGN OF THE HIGH SPEED AND HIGH PRECISION LATCHING VOLTAGE COMPARATOR ZJ03
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作者 毛培法 江来喜 《Journal of Electronics(China)》 1991年第2期163-168,共6页
The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 co... The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 comparator contains a controlled positive feedbackamplifier.Therefore,it is capable of realizing high speed and high precision.For improving theperformance and producibility,the tolerance extension,design centering and potential adaptingtechniques are used in the design of comparator ZJ03. 展开更多
关键词 VOLTAGE comparator Latching VOLTAGE comparator TOLERANCE EXTENSION POTENTIAL ADAPTING
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A Novel Power Optimization Method by Minimum Comparator Number Algorithm for Pipeline ADCs 被引量:1
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作者 宁宁 吴霜毅 +1 位作者 王向展 杨谟华 《Journal of Electronic Science and Technology of China》 2007年第1期75-80,共6页
The effects of stage numbers on power dissipation of pipeline analog-to-digital converter (ADC) are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator ... The effects of stage numbers on power dissipation of pipeline analog-to-digital converter (ADC) are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator number algorithm (MCNA) is first introduced, and then the optimum distribution of resolutions through pipeline ADC stages is deduced by MCNA. Based on the optimum stage-resolution distribution, an optimization method is established, which examines the precise function between ADC power and stage resolutions with a parameter of power ratio (Rp). For 10-bit pipeline ADC with scaling down technology, the simulation results by using MATLAB CAD tools show that an eight-stage topology with 1-bit RSD correction achieves the power optimization indicated by the power reduction ratio. 展开更多
关键词 minimum comparator number algorithm pipeline analog-to-digital converter power dissipation scaling down stage resolution
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