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从Google Trends看“一带一路”倡议的国际反响
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作者 汤宏波 李富山 +1 位作者 赵素婷 吕新华 《情报探索》 2024年第5期122-127,共6页
[目的/意义]2013年中国提出“一带一路”倡议,这对推动我国继续繁荣发展并为全球提供中国治理体系方案等具有重大意义。[方法/过程]利用Google Trends,分析中国“一带一路”倡议的国际反响及其潜在阻碍因子。[结果/结论]“一带一路”倡... [目的/意义]2013年中国提出“一带一路”倡议,这对推动我国继续繁荣发展并为全球提供中国治理体系方案等具有重大意义。[方法/过程]利用Google Trends,分析中国“一带一路”倡议的国际反响及其潜在阻碍因子。[结果/结论]“一带一路”倡议受到国际上绝大多数国家民众的支持和关注;个别国家为了压制中国的国际影响力,通过“债务陷阱外交”“珍珠链战略”以及环境问题等方面抹黑“一带一路”,行动上提出“重建更好世界”等企图替代中国的“一带一路”倡议。得益于“一带一路”倡议投资没有附加条件以及G7国家内部自身问题,“一带一路”倡议仍然获得了广大第三世界国家的支持,并将继续是推动世界经济发展的重要力量。 展开更多
关键词 “一带一路”倡议 国际反响 Google trends
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Human brain organoid:trends,evolution,and remaining challenges 被引量:1
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作者 Minghui Li Yuhan Yuan +3 位作者 Zongkun Hou Shilei Hao Liang Jin Bochu Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2387-2399,共13页
Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and a... Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and advancements in brain organoids,few studies have comprehensively summarized and analyzed the global trends in this area of neuroscience.To identify and further facilitate the development of cerebral organoids,we utilized bibliometrics and visualization methods to analyze the global trends and evolution of brain organoids in the last 10 years.First,annual publications,countries/regions,organizations,journals,authors,co-citations,and keywords relating to brain organoids were identified.The hotspots in this field were also systematically identified.Subsequently,current applications for brain organoids in neuroscience,including human neural development,neural disorders,infectious diseases,regenerative medicine,drug discovery,and toxicity assessment studies,are comprehensively discussed.Towards that end,several considerations regarding the current challenges in brain organoid research and future strategies to advance neuroscience will be presented to further promote their application in neurological research. 展开更多
关键词 bibliometric analysis brain organoids cerebral organoids global trends NEUROSCIENCE
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General anesthetic agents induce neurotoxicity through oligodendrocytes in the developing brain 被引量:1
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作者 Wen-Xin Hang Yan-Chang Yang +7 位作者 Yu-Han Hu Fu-Quan Fang Lang Wang Xing-Hua Qian Patrick M.McQuillan Hui Xiong Jian-Hang Leng Zhi-Yong Hu 《Zoological Research》 SCIE CSCD 2024年第3期691-703,共13页
General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath for... General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath formation,axonal metabolism,and neuroplasticity regulation.They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation,differentiation,and apoptosis.Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes.These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways,but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function.In this review,we summarize the effects of general anesthetic agents on oligodendrocytes.We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents. 展开更多
关键词 OLIGODENDROCYTES general anesthetic agents NEUROTOXICITY Central nervous system Perioperative neurocognitive disorders
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Extended wet sieving method for determination of complete particle size distribution of general soils 被引量:1
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作者 Shengnan Ma Yi Song +2 位作者 Jiawei Liu Xingyu Kang Zhongqi Quentin Yue 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期242-257,共16页
The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional meth... The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional method and presents an extended wet sieving method.The extended method uses both the steel sieves and the nylon filter cloth sieves.The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm,0.038 mm,0.014 mm,0.012 mm,0.0063 mm,0.004 mm,0.003 mm,0.002 mm,and 0.001 mm,respectively.The extended method uses five steps to separate the general soil into many material sub-groups of gravel,sand,silt and clay with known particle size ranges.The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups.The extended method is demonstrated with a general soil of completely decomposed granite(CDG)in Hong Kong,China.The silt and clay materials with different particle size ranges are further examined,checked and verified using stereomicroscopic observation,physical and chemical property tests.The results further confirm the correctness of the extended wet sieving method. 展开更多
关键词 Particle size distribution(PSD) general soil SILT CLAY Wet sieving Physical and chemical properties
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General anesthetic agents induce neurotoxicity through astrocytes 被引量:1
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作者 Yanchang Yang Tiantian Liu +8 位作者 Jun Li Dandan Yan Yuhan Hu Pin Wu Fuquan Fang Patrick M.McQuillan Wenxin Hang Jianhang Leng Zhiyong Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1299-1307,共9页
Neuroscientists have recognized the importance of astrocytes in regulating neurological function and their influence on the release of glial transmitters.Few studies,however,have focused on the effects of general anes... Neuroscientists have recognized the importance of astrocytes in regulating neurological function and their influence on the release of glial transmitters.Few studies,however,have focused on the effects of general anesthetic agents on neuroglia or astrocytes.Astrocytes can also be an important target of general anesthetic agents as they exert not only sedative,analgesic,and amnesic effects but also mediate general anesthetic-induced neurotoxicity and postoperative cognitive dysfunction.Here,we analyzed recent advances in understanding the mechanism of general anesthetic agents on astrocytes,and found that exposure to general anesthetic agents will destroy the morphology and proliferation of astrocytes,in addition to acting on the receptors on their surface,which not only affect Ca^(2+)signaling,inhibit the release of brain-derived neurotrophic factor and lactate from astrocytes,but are even involved in the regulation of the pro-and anti-inflammatory processes of astrocytes.These would obviously affect the communication between astrocytes as well as between astrocytes and neighboring neurons,other neuroglia,and vascular cells.In this review,we summarize how general anesthetic agents act on neurons via astrocytes,and explore potential mechanisms of action of general anesthetic agents on the nervous system.We hope that this review will provide a new direction for mitigating the neurotoxicity of general anesthetic agents. 展开更多
关键词 ASTROCYTES brain-derived neurotrophic factor general anesthetic agents neuron NEUROTOXICITY N-methyl-D-aspartate receptor perioperative neurocognition Toll-like receptor γ-aminobutyric acid receptor
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Effects of temperature and precipitation on drought trends in Xinjiang, China
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作者 YANG Jianhua LI Yaqian +3 位作者 ZHOU Lei ZHANG Zhenqing ZHOU Hongkui WU Jianjun 《Journal of Arid Land》 SCIE CSCD 2024年第8期1098-1117,共20页
The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and pre... The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and precipitation—the two most important factors influencing drought—have not yet been thoroughly explored in this region.In this study,we first calculated the standard precipitation evapotranspiration index(SPEI)in Xinjiang from 1980 to 2020 based on the monthly precipitation and monthly average temperature.Then the spatiotemporal characteristics of temperature,precipitation,and drought in Xinjiang from 1980 to 2020 were analyzed using the Theil-Sen median trend analysis method and Mann-Kendall test.A series of SPEI-based scenario-setting experiments by combining the observed and detrended climatic factors were utilized to quantify the effects of individual climatic factor(i.e.,temperature and precipitation).The results revealed that both temperature and precipitation had experienced increasing trends at most meteorological stations in Xinjiang from 1980 to 2020,especially the spring temperature and winter precipitation.Due to the influence of temperature,trends of intensifying drought have been observed at spring,summer,autumn,and annual scales.In addition,the drought trends in southern Xinjiang were more notable than those in northern Xinjiang.From 1980 to 2020,temperature trends exacerbated drought trends,but precipitation trends alleviated drought trends in Xinjiang.Most meteorological stations in Xinjiang exhibited temperature-dominated drought trend except in winter;in winter,most stations exhibited precipitation-dominated wetting trend.The findings of this study highlight the importance of the impact of temperature on drought in Xinjiang and deepen the understanding of the factors influencing drought. 展开更多
关键词 standardized precipitation evapotranspiration index(SPEI) climate change drought characteristics trend analysis arid area temperature trend contribution analysis
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Bibliometric analysis of hotspots and trends of global myopia research
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作者 Xing-Yang Wu Hui-Hui Fang +3 位作者 Yan-Wu Xu Yan-Ling Zhang Shao-Chong Zhang Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期940-950,共11页
AIM:To gain insights into the global research hotspots and trends of myopia.METHODS:Articles were downloaded from January 1,2013 to December 31,2022 from the Science Core Database website and were mainly statistically... AIM:To gain insights into the global research hotspots and trends of myopia.METHODS:Articles were downloaded from January 1,2013 to December 31,2022 from the Science Core Database website and were mainly statistically analyzed by bibliometrics software.RESULTS:A total of 444 institutions in 87 countries published 4124 articles.Between 2013 and 2022,China had the highest number of publications(n=1865)and the highest H-index(61).Sun Yat-sen University had the highest number of publications(n=229)and the highest H-index(33).Ophthalmology is the main category in related journals.Citations from 2020 to 2022 highlight keywords of options and reference,child health(pediatrics),myopic traction mechanism,public health,and machine learning,which represent research frontiers.CONCLUSION:Myopia has become a hot research field.China and Chinese institutions have the strongest academic influence in the field from 2013 to 2022.The main driver of myopic research is still medical or ophthalmologists.This study highlights the importance of public health in addressing the global rise in myopia,especially its impact on children’s health.At present,a unified theoretical system is still needed.Accurate surgical and therapeutic solutions must be proposed for people with different characteristics to manage and intervene refractive errors.In addition,the benefits of artificial intelligence(AI)models are also reflected in disease monitoring and prediction. 展开更多
关键词 bibliometric analysis MYOPIA global trends
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Analysis of the spatiotemporal trends and influencing factors of Hyphantria cunea in China
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作者 Hongwei Zhou Chaoqun Gong +2 位作者 Xiaodong Li Yue Wang Yunbo Yan 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期294-305,共12页
In recent years,the situation of the Hyphantria cunea(Drury)(Lepidoptera:Erebidae),infestation in China has been serious and has a tendency to continue to spread.A comprehensive analysis was carried out to examine the... In recent years,the situation of the Hyphantria cunea(Drury)(Lepidoptera:Erebidae),infestation in China has been serious and has a tendency to continue to spread.A comprehensive analysis was carried out to examine the spa-tial distribution trends and influencing factors of H.cunea.This analysis involved integrating administrative division and boundary data,distribution data of H.cunea,and envi-ronmental variables for 2021.GeoDetector and gravity analysis techniques were employed for data processing and interpretation.The results show that H.cunea exhibited high aggregation patterns in 2021 and 2022 concentrated mainly in eastern China.During these years,the focal point of the infestation was in Shandong Province with a spread towards the northeast.Conditions such as high vegetation density in eastern China provided favorable situations for growth and development of H.cunea.In China,the spatial distribution of the moth is primarily influenced by two critical factors:precipitation during the driest month and elevation.These play a pivotal role in determining the spread of the species.Based on these results,suggestions are provided for a mul-tifaceted approach to prevention and control of H.cunea infestation. 展开更多
关键词 Hyphantria cunea Temporal trends GeoDetector spatial analysis Spatial heterogeneity
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Data-enhanced revealing of trends in Geoscience
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作者 Yu Zhao Meng Wang +6 位作者 Jiaxin Ding Jiexing Qi Lyuwen Wu Sibo Zhang Luoyi Fu Xinbing Wang Li Cheng 《Journal of Data and Information Science》 CSCD 2024年第3期29-43,共15页
Purpose:This article presents an in-depth analysis of global research trends in Geosciences from 2014 to 2023.By integrating bibliometric analysis with expert insights from the Deep-time Digital Earth(DDE)initiative,t... Purpose:This article presents an in-depth analysis of global research trends in Geosciences from 2014 to 2023.By integrating bibliometric analysis with expert insights from the Deep-time Digital Earth(DDE)initiative,this article identifies key emerging themes shaping the landscape of Earth Sciences①.Design/methodology/approach:The identification process involved a meticulous analysis of over 400,000 papers from 466 Geosciences journals and approximately 5,800 papers from 93 interdisciplinary journals sourced from the Web of Science and Dimensions database.To map relationships between articles,citation networks were constructed,and spectral clustering algorithms were then employed to identify groups of related research,resulting in 407 clusters.Relevant research terms were extracted using the Log-Likelihood Ratio(LLR)algorithm,followed by statistical analyses on the volume of papers,average publication year,and average citation count within each cluster.Additionally,expert knowledge from DDE Scientific Committee was utilized to select top 30 trends based on their representation,relevance,and impact within Geosciences,and finalize naming of these top trends with consideration of the content and implications of the associated research.This comprehensive approach in systematically delineating and characterizing the trends in a way which is understandable to geoscientists.Findings:Thirty significant trends were identified in the field of Geosciences,spanning five domains:deep space,deep time,deep Earth,habitable Earth,and big data.These topics reflect the latest trends and advancements in Geosciences and have the potential to address real-world problems that are closely related to society,science,and technology.Research limitations:The analyzed data of this study only contain those were included in the Web of Science.Practical implications:This study will strongly support the organizations and individual scientists to understand the modern frontier of earth science,especially on solid earth.The organizations such as the surveys or natural science fund could map out areas for future exploration and analyze the hot topics reference to this study.Originality/value:This paper integrates bibliometric analysis with expert insights to highlight the most significant trends on earth science and reach the individual scientist and public by global voting. 展开更多
关键词 GEOSCIENCES Research trends BIBLIOMETRICS Expert knowledge Global voting
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Global Scientific Trends in Research Related to Diabetic Sarcopenia from 1993 to 2023: A Bibliometric Analysis
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作者 Qing Yang Yuan Zhao +2 位作者 Han Lu Yaolei Cha Lijie Yang 《Journal of Biosciences and Medicines》 2024年第3期204-222,共19页
Objectives: In this study, bibliometric approach was used to explore the literature in the field of research related to Diabetic Myasthenia Gravis in order to identify the current research progress in Diabetic Myasthe... Objectives: In this study, bibliometric approach was used to explore the literature in the field of research related to Diabetic Myasthenia Gravis in order to identify the current research progress in Diabetic Myasthenia Gravis related research and to help the researchers to predict the future hotspots in the field of research and to provide reference for the research. Methods: Literature related to diabetic sarcopenia published from 1993 to 2023 since the inception of the repository was extracted from the Web of Science Core Collection (WoSCC) and bibliometric analyses were performed. We have analysed the published literature of the last approximately almost 30 years, as well as publication and citation analyses from different countries, institutions, journals and authors. For keywords, we performed co-occurrence, clustering, timeline view and citation burst analysis. Results: On the basis of 1564 publications, we found a continuous increase in the number of publications and citations, especially in the last six years. The United States is the most representative country, and Seoul National University (SNU) is the most representative institution. The most popular journal in the field is Diabetes Care;Fukui, Michiaki is the most prolific author, leading many studies related to diabetic sarcopenia. The most frequently cited reference was a revised European consensus on the definition and diagnosis of sarcopenia;the most cited keywords were related to physiological factors of diabetes, sarcopenia and related conditions, such as “insulin resistance”, “skeletal muscle”, “body composition”, “risk” and “prevalence”. Conclusion: With more and more studies on the relationship between diabetic sarcopenia, this study presents the current status and trend of research related to diabetic sarcopenia over the past nearly 30 years through the visualization software CiteSpace. It can help researchers identify potential collaborators and partner institutions, hotspots and research frontiers in the field of diabetic sarcopenia. However, our work is only based on the English language literature in the WoSCC database, and for future studies, we recommend that researchers explore the literature from multiple databases to enhance the scope of their research. 展开更多
关键词 DIABETES SARCOPENIA BIBLIOMETRICS Research trends Citespace
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Climate Trends and Their Impact on Sorghum Production in Marigat, Baringo County: A Historical Analysis
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作者 Kennedy O. Okuku Japheth O. Onyando +1 位作者 Romulus O. Okwany Clement K. Kiptum 《Open Journal of Modern Hydrology》 CAS 2024年第2期106-129,共24页
Climate is subject to fluctuations in the majority of the world, mainly caused by rainfall as well as temperature variations. Climate fluctuations in Kenya have resulted in the spread of desert-like conditions in the ... Climate is subject to fluctuations in the majority of the world, mainly caused by rainfall as well as temperature variations. Climate fluctuations in Kenya have resulted in the spread of desert-like conditions in the ASALs region, such as Marigat in Baringo County. As a county, Baringo experiences great variations in climate annually, as well as uncertainty in expected rains, thereby negatively impacting the production of crops such as sorghum. This study applied the rainfall anomaly index (RAI), standardised precipitation evapotranspiration index (SPEI), standard precipitation index (SPI), and Mann-Kendall (MK) statistical test for trends on historical climatic data in analysing both temperature and precipitation data over the period 1990 to 2022 to determine their trend, patterns and how they affect the production of sorghum crops. The machine learning method (R studio) with inputs was used to calculate the SPI, SPEI, RAI and MK trend test. The rainfall varied from below average to above average during the study period with no clear pattern in the RAI, SPEI and SPI values. The years 2020 and 2000 stood out as they had higher and lower rainfall than usual, respectively. The Marigat area generally experienced more rainfall during the high/long rainfall season (AMJJ). The MK trend test on average monthly rainfall, SOND, AMJJ, and annual precipitation confirmed a positive trend in precipitation. However, the short rainy season (SOND) was found to be the most variable period for rainfall, and there was a slight increase in daily average temperatures during this season. 展开更多
关键词 trends PRECIPITATION Temperature RAI SPI SPEI and MK
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Esophageal cancer global burden profiles, trends, and contributors
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作者 Yi Teng Changfa Xia +9 位作者 Maomao Cao Fan Yang Xinxin Yan Siyi He Mengdi Cao Shaoli Zhang Qianru Li Nuopei Tan Jiachen Wang Wanqing Chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第8期656-666,共11页
Objective:This study aimed to provide a comprehensive overview of the global burden of esophageal cancer(EC)and determine the temporal trends and factors influencing changes in the global burden.Methods:The latest inc... Objective:This study aimed to provide a comprehensive overview of the global burden of esophageal cancer(EC)and determine the temporal trends and factors influencing changes in the global burden.Methods:The latest incidence and mortality data for EC worldwide were obtained from GLOBALCAN 2022.The mortality and disability-adjusted life years(DALYs)rates for EC from 1990±2019 were sourced from the 2019 Global Burden of Diseases.Trends in EC mortality and DALYs attributable to 11 risk factors or clusters of risk were analyzed using the joinpoint regression model.The trends in age-related EC burden were assessed using a decomposition approach.Results:An estimated 511,054 new cases of EC were diagnosed in 2022 with 445,391 deaths worldwide.Approximately 75%of cases and deaths occurred in Asia.Nearly 50%of global EC deaths and DALYs were attributed to tobacco use in men in 2019,while 20%were attributed to high body mass index(BMI)in women.From 1990±2019,EC deaths and DALYs attributable to almost all risk factors had declining trends,while EC deaths and DALYs attributed to high BMI in men had upward trends.The age-related EC burden exhibited an upward trend driven by population growth and aging,which contributed to 307.4 thousand deaths and 7.2 million DALYs due to EC.Conclusions:The EC burden remains substantial worldwide.Effective tobacco and obesity control measures are critical for addressing the risk-attributable burden of EC.Population growth and aging pose challenges for EC prevention and control efforts. 展开更多
关键词 Esophageal cancer INCIDENCE MORTALITY disability-adjusted life years risk factors AGING trends
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Systematic bibliometric analysis of research hotspots and trends on the application of premium IOLs in the past 2 decades
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作者 Liang-Pin Li Li-Yun Yuan +2 位作者 De-Shen Mao Xia Hua Xiao-Yong Yuan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期736-747,共12页
AIM:To analysis of research hotspots and trends on the application of premium intraocular lens(PIOLs)in the past 2 decades.METHODS:The literature search was performed on the Web of Science and included PIOLs studies p... AIM:To analysis of research hotspots and trends on the application of premium intraocular lens(PIOLs)in the past 2 decades.METHODS:The literature search was performed on the Web of Science and included PIOLs studies published between January 2000 and December 2022.The retrieved literature was collated and analyzed by R-tool’s Bibliometrix package,CitNetExplorer,CiteSpace and other software.RESULTS:A total of 1801 articles about PIOLs were obtained,most of which were published in Spain and the United States.The organization that published the most articles was the University of Valencia in Spain.Alió JL,and Montés-Micó R,from Spain were the most influential authors in this field.The Journal of Cataract and Refractive Surgery and Journal of Refractive Surgery were the core journals for this field;the top 10 cited articles mainly focus on postoperative satisfaction with multifocal intraocular lens(IOLs)and postoperative results of toric IOLs.Through the keyword analysis,we found that trifocal IOLs,astigmatism and extended depth of focus(EDoF)IOLs are the most discussed topics at present,and the importance of astigmatism and the clinical application of the new generation of PIOLs are the emerging research trends.CONCLUSION:Bibliometric analysis can effectively help to identify multilevel concerns in PIOLs research and the prevailing research trends in the realm of PIOLs encompass the adoption of EDoF IOLs,trifocal IOLs,and their respective Toric models. 展开更多
关键词 premium intraocular lens BIBLIOMETRIC H-INDEX cataract surgery global trends
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A nonlocal dispersal and time delayed HIV infection model with general incidences
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作者 WU Peng ZHANG Yu-huai WANG Ling 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期448-457,共10页
Biologically,because of the impact of reproduction period and nonlocal dispersal of HIV-infected cells,time delay and spatial heterogeneity should be considered.In this paper,we establish an HIV infection model with n... Biologically,because of the impact of reproduction period and nonlocal dispersal of HIV-infected cells,time delay and spatial heterogeneity should be considered.In this paper,we establish an HIV infection model with nonlocal dispersal and infection age.Moreover,applying the theory of Fourier transformation and von Foerster rule,we transform the model to an integrodifferential equation with nonlocal time delay and dispersal.The well-posedness,positivity,and boundedness of the solution for the model are studied. 展开更多
关键词 HIV model nonlocal dispersal time delay general incidences
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Global trends of tropopause folds in recent decades 被引量:1
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作者 Yufeng Lin Wenshou Tian +4 位作者 Haiyang Xue Jiali Luo Jiankai Zhang Hongying Tian Wenjun Liang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第3期14-19,共6页
对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总... 对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总体上,对流层顶折卷呈增加趋势,其中北半球的春季,夏季和冬季,对流层顶折卷主要沿副热带急流区呈现明显增加的趋势.进一步分析表明,对流层顶折卷发生频率的增加与大气斜压性增大导致的锋生增强有关,而经向位温梯度的增大使得次级环流增强,也可能促进了对流层顶折卷活动的增多. 展开更多
关键词 对流层顶折卷 趋势 锋生 大气斜压性
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NORMALIZED SOLUTIONS FOR THE GENERAL KIRCHHOFF TYPE EQUATIONS
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作者 Wenmin LIU Xuexiu ZHONG Jinfang ZHOU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1886-1902,共17页
In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constrain... In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constraint f_(R)^N u^2dx=c,where M∈C([0,∞))is a given function satisfying some suitable assumptions.Our argument is not by the classical variational method,but by a global branch approach developed by Jeanjean et al.[J Math Pures Appl,2024,183:44–75]and a direct correspondence,so we can handle in a unified way the nonlinearities g(s),which are either mass subcritical,mass critical or mass supercritical. 展开更多
关键词 normalized solution Kirchhoff type equations general nonlinearities asymptotic behavior
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Higher-order expansions of powered extremes of logarithmic general error distribution
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作者 TAN Xiao-feng LI Li-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期47-54,共8页
In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of nor... In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing constants.It is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v). 展开更多
关键词 logarithmic general error distribution convergence rate higher-order expansion powered ex-treme
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Image Steganography by Pixel-Value Differencing Using General Quantization Ranges
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作者 Da-Chun Wu Zong-Nan Shih 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期353-383,共31页
A new steganographic method by pixel-value differencing(PVD)using general quantization ranges of pixel pairs’difference values is proposed.The objective of this method is to provide a data embedding technique with a ... A new steganographic method by pixel-value differencing(PVD)using general quantization ranges of pixel pairs’difference values is proposed.The objective of this method is to provide a data embedding technique with a range table with range widths not limited to powers of 2,extending PVD-based methods to enhance their flexibility and data-embedding rates without changing their capabilities to resist security attacks.Specifically,the conventional PVD technique partitions a grayscale image into 1×2 non-overlapping blocks.The entire range[0,255]of all possible absolute values of the pixel pairs’grayscale differences in the blocks is divided into multiple quantization ranges.The width of each quantization range is a power of two to facilitate the direct embedding of the bit information with high embedding rates.Without using power-of-two range widths,the embedding rates can drop using conventional embedding techniques.In contrast,the proposed method uses general quantization range widths,and a multiple-based number conversion mechanism is employed skillfully to implement the use of nonpower-of-two range widths,with each pixel pair being employed to embed a digit in the multiple-based number.All the message bits are converted into a big multiple-based number whose digits can be embedded into the pixel pairs with a higher embedding rate.Good experimental results showed the feasibility of the proposed method and its resistance to security attacks.In addition,implementation examples are provided,where the proposed method adopts non-power-of-two range widths and employsmultiple-based number conversion to expand the data-hiding and steganalysis-resisting capabilities of other PVD methods. 展开更多
关键词 STEGANOGRAPHY pixel-value differencing multiple-based number conversion general quantization range
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Intelligent Transformation: General Intelligence Theory
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作者 Alexander Ngu Amaya Odilon Kosso 《International Journal of Intelligence Science》 2024年第3期59-70,共12页
This paper aims to formalize a general definition of intelligence beyond human intelligence. We accomplish this by re-imagining the concept of equality as a fundamental abstraction for relation. We discover that the c... This paper aims to formalize a general definition of intelligence beyond human intelligence. We accomplish this by re-imagining the concept of equality as a fundamental abstraction for relation. We discover that the concept of equality = limits the sensitivity of our mathematics to abstract relationships. We propose a new relation principle that does not rely on the concept of equality but is consistent with existing mathematical abstractions. In essence, this paper proposes a conceptual framework for general interaction and argues that this framework is also an abstraction that satisfies the definition of Intelligence. Hence, we define intelligence as a formalization of generality, represented by the abstraction ∆∞Ο, where each symbol represents the concepts infinitesimal, infinite, and finite respectively. In essence, this paper proposes a General Language Model (GLM), where the abstraction ∆∞Ο represents the foundational relationship of the model. This relation is colloquially termed “The theory of everything”. 展开更多
关键词 INTELLIGENCE generalIZATION ABSTRACTION TRANSFORMATION general Language Model general Intelligence Theory Theory of Everything
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Global research trends in postoperative ileus from 2011 to 2023:A scientometric study
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作者 Yan Zhou Zi-Han Yin +5 位作者 Ming-Sheng Sun Yang-Yang Wang Chen Yang Shu-Hao Li Fan-Rong Liang Fang Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期3020-3031,共12页
BACKGROUND Postoperative ileus(POI)is a common complication after abdominal surgery with high morbidity,which hinders patient recovery,prolongs hospitalization,and increases healthcare costs.Therefore,POI has become a... BACKGROUND Postoperative ileus(POI)is a common complication after abdominal surgery with high morbidity,which hinders patient recovery,prolongs hospitalization,and increases healthcare costs.Therefore,POI has become a global public health challenge.POI triggering is multifactorial.Autonomic and hormonal mechanisms are generally involved in POI pathogenesis.Recent studies have shown that beta adrenergic signaling of enteric glia is a POI trigger.Currently,the status quo,trends,and frontiers of global research on POI remain unclear.AIM To explore the current status,trends,and frontiers of POI research from 2011 to the present based on bibliometric analysis.METHODS Publications published on POI research from 2011 to 2023 were retrieved on June 1,2023,from the Web of Science Core Collection.CiteSpace 6.2.R2 and VOSviewer were used to conduct bibliometric visualization.RESULTS In total,778 POI records published from 2011 to 2023 were retrieved.Over the past few decades,the annual cumulative number of related articles has linearly increased,with China and the United States of America contributing prominently.All publications were from 59 countries and territories.China and the University of Bonn were the top contributing country and institution,respectively.Neurogastroenterology&Motility was the most prolific journal.The Journal of Gastrointestinal Surgery had the highest number of citations.Wehner Sven was the most productive author.Burst keywords(e.g.,colon,prolonged ileus,acupuncture,paralytic ileus,pathophysiology,rectal cancer,gastrointestinal function,risk)and a series of reference citation bursts provided evidence for the research frontiers in recent years.CONCLUSION This study demonstrates trends in the published literature on POI and provides new insights for researchers.It emphasizes the importance of multidisciplinary cooperation in the development of this field. 展开更多
关键词 Postoperative ileus Scientometric analysis VOSviewer CITESPACE VISUALIZATION trends
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