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‘Partly'globalized networks and driving mechanism in resource-based state-owned enterprises:A case study of J Group 被引量:1
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作者 Jing Xu Yongchun Yang +1 位作者 Yongjiao Zhang Shan Man 《Geography and Sustainability》 CSCD 2024年第1期77-88,共12页
In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in th... In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in the world market.In China,resource-based state-owned enterprises(SOEs)are tasked with the mission of safeguarding resource security,and their internationalization development ideas and strategic deployment are significantly and fundamentally different from those of other non-state-owned enterprises and large multinational corporations.This study provides ideas for the globalization policies of enterprises in developing countries.We consider J Group in western China as a case and discuss its productive investment and global production network development from 2010 to 2019.We found that J Group was‘Partly'globalized,and there are multiple core nodes with the characteristics of centralized and decentralized coexistence in the production network;in addition,the overall layout centre shifted to Southeast Asia and China;however,its global production was restricted by the enterprise's investment security considerations,support and restrictions of the home country,political security risk of the host country,and sanctions from the West.These findings provide insights for future research:under the wave of anti-globalization and'internal circulation as the main body',resource SOEs should consider the potential risk of investment,especially keeping the middle and downstream industrial chain in China as much as possible. 展开更多
关键词 Global production networks Global value chain Productive investment Resource SOEs J Group ‘Partly'globalized
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Cultural Identity in the Development of Cultural Trade in the Globalized Age
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作者 孙雅静 高凤翔 《海外英语》 2011年第8X期318-320,共3页
The nature of cultural trade is the acknowledgement and acceptance of the cultural identity of different nationalities or countries. Cultural trade have its root in the contention for the resources of cultural identit... The nature of cultural trade is the acknowledgement and acceptance of the cultural identity of different nationalities or countries. Cultural trade have its root in the contention for the resources of cultural identity. As a matter of fact, globalization is not simply homogenization; however, it enhances the diversity of cultural identity.Based on the economic principle, this paper aims to analyze the influences of globalization on culture, and explain the phenomenon of cultural identity caused during this process. Furthermore, through the analysis of the role of cultural identity, some feasible solutions to enhance the Chinese competitiveness of cultural trade are suggested. 展开更多
关键词 GLOBALIZATION CULTURAL PRODUCT CULTURAL TRADE CULTURAL IDENTITY
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Facility Management in the Globalized Society
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作者 Bortosova Viera Valaskova Katarina 《Management Studies》 2018年第5期358-366,共9页
Facility management is the multi-disciplinary kind of work that covers a wide range of various activities, responsibilities, and knowledge. Facility management provides and manages a variety of support services in ord... Facility management is the multi-disciplinary kind of work that covers a wide range of various activities, responsibilities, and knowledge. Facility management provides and manages a variety of support services in order to prepare all the organisational functions, putting the accent on an integration of primary activities in strategic, tactical, and operational levels. In the final decade of the previous century, facility mmmgement industry emerged as one of the fastest growing sectors at the international level. Nowadays, the importance of the facility management is readily acknowledged in many companies worldwide, which recognises the necessity of properly managing elaborate and expensive support facilities. The tasks are multi-disciplinary and cover a wide range of activities, responsibilities, and knowledge, because every aspect of an organisation may come under the competency of the facility management. The main aim of the paper is to point out the well-founded applicability of the global facility management in companies, which in order to achieve the competitive advantage correctly strengthened the corporate core business and shift the support activities into the management of a specialist in this field. The paper also covers the scope of the facility management in the international context, and also in the Slovak Republic, considering the specificities of individual countries 展开更多
关键词 facility management support process corporate management GLOBALIZATION
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我国农业农村科技现代化的实现效率探究
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作者 徐小俊 杨钟健 高秉龙 《山西农业大学学报(社会科学版)》 2025年第1期44-55,共12页
科学技术是第一生产力,是国家发展的核心战略力量。对于农业农村科技现代化实现效率的研究,有助于了解我国农业农村科技现代化推进过程中存在的问题,为相关决策提供可靠的参考依据。基于熊彼特创新理论的分析框架,构建Global Super SBM... 科学技术是第一生产力,是国家发展的核心战略力量。对于农业农村科技现代化实现效率的研究,有助于了解我国农业农村科技现代化推进过程中存在的问题,为相关决策提供可靠的参考依据。基于熊彼特创新理论的分析框架,构建Global Super SBM模型,对我国农业农村科技现代化的实现效率进行了实证分析。研究表明:当前我国各地区对农业农村科技现代化的重视程度不断增加,促进了整体效率的提升,但是区域的不平衡性问题突出;虽然我国部分地区能够发挥好自身的比较优势或后发优势,但可能由于地区经济结构相对复杂,导致资源投入分散,或者投入较大而投入效率不高而导致实现效率较低;地区间农业农村科技现代化实现效率的差异可能引发各地区内部技术进步的不均衡性。基于此,提出需要从发掘农业农村科技创新动能、优化农业农村资源要素配置、缩小农业农村地区技术差异等方面提升我国农业农村科技现代化的实现效率。 展开更多
关键词 农业农村 科技现代化 实现效率 Global Super SBM模型
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融合激光测高数据的无控GF-7卫星影像矿区DSM改进方法
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作者 张云龙 胡文敏 +3 位作者 魏伟 秦凯 徐嘉兴 张炜 《遥感学报》 北大核心 2025年第9期2700-2713,共14页
针对沟壑发育地表无地面控制点GCPs(Ground Control Points)条件下卫星遥感立体影像地形三维重建精度较低、大面积GCPs采集困难或成本高等问题,本文提出融合卫星激光测高数据的高分七号(GF-7)卫星影像数字表面模型DSM(Digital Surface M... 针对沟壑发育地表无地面控制点GCPs(Ground Control Points)条件下卫星遥感立体影像地形三维重建精度较低、大面积GCPs采集困难或成本高等问题,本文提出融合卫星激光测高数据的高分七号(GF-7)卫星影像数字表面模型DSM(Digital Surface Model)BP神经网络方法。该方法通过建立无控条件下GF-7卫星立体影像生成的DSM、地理位置经度与纬度、地形坡度、地形误差等多因子与激光测高点GEDI(Global Ecosystem Dynamics Investigation)之间的关系,获取融合结果以改进无控条件下地形DSM精度。实验结果表明,沟壑发育地表矿区无控条件下GF-7卫星立体影像生成的DSM高程精度可高达20.49 m,而本文融合生成的DSM平均高程精度为1.63 m,与有控制点条件下地形DSM 1.44 m的高程精度基本相当。本文方法有效改善了沟壑发育地表矿区无控条件下卫星立体影像生成DSM高程精度质量低的问题,为国产高分影像推广应用与高精度地形建模提供新思路。 展开更多
关键词 数字表面模型 地面控制点 神经网络 沟壑发育地表 GF-7卫星立体影像 GEDI(Global Ecosystem Dynamics Investigation)
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The Emergence of a Globalized System for Disaster Risk Management and Challenges for Appropriate Governance 被引量:2
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作者 Steven JJensen Shirley Feldmann-Jensen +1 位作者 David MJohnston Nancy ABrown 《International Journal of Disaster Risk Science》 SCIE CSCD 2015年第1期87-93,共7页
Disaster risk management(DRM) is undergoing noteworthy changes, reflecting the broader shifts in global and local levels of governance. At the global level two significant changes are of interest:(1) the shift from mo... Disaster risk management(DRM) is undergoing noteworthy changes, reflecting the broader shifts in global and local levels of governance. At the global level two significant changes are of interest:(1) the shift from monolithic structures of global governance to a wide range of organizations that can be brought together for specific purposes and(2) the emergence of a globalized system of DRM, with technological, organizational, and institutional capacities enhancing DRM’s ability as a unit in near real time across the globe. At the local level there is an increase in ability to govern and develop creative solutions for complex problems that follow rapid urbanization. The importance of getting the global–local interface to work in tandem has been highlighted by recent hazard events, such as the 2011 Tohoku Earthquake and Tsunami. From a broad view of global and local shifts, a strategic role is becoming clearer at the national level for enhancing the relationships between the global and local levels. Through the influence of a globalized system of DRM, the local level can significantly improve its capacity without the heavy investment that might have been required to develop these capacities in isolation. One key to achieving this is adiffusion of DRM higher education, supported by an enhanced system of information flow. 展开更多
关键词 Disaster risk management Global governance GLOBALIZATION globalized systems Local governance National governance
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From Chinese Version of Integrative Medicine to Globalized Integrative Medicine:Impression on the 3rd World Integrative Medicine Congress 被引量:3
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作者 陈可冀 吕爱平 《Chinese Journal of Integrative Medicine》 SCIE CAS 2007年第4期244-245,共2页
In the 1950's, Chinese medical scientists were trying to take advantage of both Western medicine and traditional Chinese medicine in clinical practice. The integrated traditional Chinese medicine and Western medicine... In the 1950's, Chinese medical scientists were trying to take advantage of both Western medicine and traditional Chinese medicine in clinical practice. The integrated traditional Chinese medicine and Western medicine became an academic branch in medical sciences. As more and more medical doctors were involved in the Chinese version of integrative medicine, an academic organization, the Chinese Association of the Integration of Traditional and Western Medicine (now named the Chinese Association of the Integrative Medicine) was established in 1981 aiming to strengthen the academic exchanges in Chinese version of integrative medicine. 展开更多
关键词 World From Chinese Version of Integrative Medicine to globalized Integrative Medicine
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Data-Driven Prediction in Complex Systems of Virus Evolution and Global Warming 被引量:1
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作者 LUO Liaofu LÜJun 《内蒙古大学学报(自然科学版)》 2025年第1期1-7,共7页
A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(da... A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(data-driven prediction).This suggests that the essential dynamics of a complex system can be captured through a low-dimensional representation.Virus evolution and climate change are two examples of complex,time-varying systems.In this article,we show that mutations in the spike protein provide valuable data for predicting SARS-CoV-2 variants,forecasting the possible emergence of the new macro-lineage Q in the near future.Our analysis also demonstrates that carbon dioxide concentration is a reliable indicator for predicting the evolution of the climate system,extending global surface air temperature(GSAT)forecasts through 2500. 展开更多
关键词 data-drivenprediction complex system virus evolution global warming
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Late spring-early summer drought and soil properties jointly modulate two pine species?decline and climatic sensitivity in temperate Northern China 被引量:1
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作者 Yuheng Li Zhaofei Fan +10 位作者 Lihong Xu Xiao Zhang Zhongjie Shi Xiaohui Yang Wei Xiong Ling Cong Semyun Kwon Leilei Pan f Hanzhi Li Shuo Wen Xiaoyan Shang 《Forest Ecosystems》 2025年第1期146-158,共13页
Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts o... Increasing temperatures and severe droughts threaten forest vitality globally.Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts on the growth of tree species,likely driven by local climatic aridity,climate trends,edaphic conditions,and the climatic adaption of tree species.The ability of tree species to cope with changing climate and the effects of environmental variables on growth trends and growth-climate relationships across diverse bioclimatic regions are still poorly understood for many species.This study investigated radial growth trends,interannual growth variability,and growth-climate sensitivity of two dominant tree species,Pinus tabulaeformis(PT)and Pinus sylvestris var.mongolica(PS),across a broad climatic gradient with a variety of soil properties in temperate Northern China.Using a network of 83 tree ring chronologies(54 for PT and 29 for PS)from 1971 to 2010,we documented that both species maintained constant growth trends at wet sites,while both displayed rapid declines at dry sites.We reported the species-specific drivers of spatial heterogeneity in growth trends,interannual growth variability,and growth-climate relationships.Calculated climatic variables and soil properties were identified as the most critical factors affecting the growth trends and growth-climate relationships.However,climatic variables play more essential roles than soil properties in determining the spatial heterogeneity of the growth-climate relationship.Lower clay content and higher soil nutrient regimes can exacerbate the moisture-related susceptibility of tree growth.Our findings highlight that soil properties emerged as important modulating factors to predict the drought vulnerability of forests in addition to climatic variables.Considering the continued climate warmingdrying trend in the future,both pines will face a more severe growth decline and increase in drought vulnerability at drier sites with lower clayed soil or higher nutrient regimes. 展开更多
关键词 Tree rings Climate sensitivity Growth decline Global warming DROUGHT Soil property
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Potential reduction of global colorectal cancer,1990–2021 被引量:1
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作者 Zilin Luo Xuesi Dong +10 位作者 Le Wang Yadi Zheng Chenran Wang Jiaxin Xie Xiaolu Chen Liang Zhao Yongjie Xu Wei Cao Fei Wang Lingbin Du Ni Li 《Journal of the National Cancer Center》 2025年第3期313-321,共9页
Objectives Primary prevention targeting modifiable risk factors would reduce the global burden of colorectal cancer,but the quantitative results are uncertain.We aimed to assess the global burden of colorectal cancer ... Objectives Primary prevention targeting modifiable risk factors would reduce the global burden of colorectal cancer,but the quantitative results are uncertain.We aimed to assess the global burden of colorectal cancer attributed to modifiable lifestyle factors and quantify the potential increase in life expectancy resulting from the elimination of these risk factors.Methods Based on the Global Burden of Disease Study 2021,we examined colorectal cancer deaths and disability-adjusted life years attributed to modifiable risk factors(including smoking,diet low in whole grains,diet low in milk,diet high in red meat,diet low in calcium,diet high in processed meat,and diet low in fiber)at the global,regional,and national levels from 1990 to 2021.The abridged period life table method was utilized to quantify the potential gain in life expectancy from eliminating these risk factors.Results Globally in 2021,57.1%of colorectal cancer deaths and 56.4%of disability-adjusted life years were preventable,with rates of 7.55(4.94–9.64)and 174.67(114.54–222.24)per 100,000 population,respectively.The modifiable burden has diminished in the high,high-middle,and low socio-demographic index quintiles and remained steady in the middle one.However,there is a concerning increase in the low-middle one.In 2021,the elimination of global colorectal cancer attributed to modifiable factors would increase the life expectancy for males and females by 0.107 and 0.109 years,respectively.Conclusion Our results quantitatively demonstrate the substantial burden reduction in colorectal cancer and the significant gain in life expectancy that can be achieved by eliminating modifiable lifestyle factors. 展开更多
关键词 Colorectal cancer Modifiable Risk factors Global burden of disease
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Divergent trends in the burden of esophageal,gastric,and liver cancers in China 被引量:1
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作者 Yongjie Xu Changfa Xia +2 位作者 Jiachen Wang Yujie Wu Wanqing Chen 《Journal of the National Cancer Center》 2025年第3期306-312,共7页
Background While China’s socioeconomic transformation has driven divergent trends in gastrointestinal cancers,comprehensive data on esophageal,gastric,and liver cancer burden remain limited.This study examines the gl... Background While China’s socioeconomic transformation has driven divergent trends in gastrointestinal cancers,comprehensive data on esophageal,gastric,and liver cancer burden remain limited.This study examines the global burden of esophageal,gastric,and liver cancers in 2022 and analyzes the trends of age-standardized incidence and mortality rate(ASRs)in China from 2000 to 2018,thereby providing evidence for the formulation of cancer control strategies.Methods The global burden of esophageal,gastric and liver cancers including the estimated number of cases and deaths and the ASRs for incidence and mortality were from GLOBALCAN 2022 dataset.Data from 22 cancer registries in China were employed for the trend analysis of the ASRs for incidence and mortality of these three cancers.The Joinpoint model was used to compute the average annual percentage change(AAPC)of the incidence and mortality of the three cancers from 2000 to 2018.Results Globally,esophageal,gastric and liver cancers accounted for 11.8%of incident cancer cases and 19.1%of cancer deaths.China bore a disproportionately high burden,representing 43.8%,37.0%,and 42.4%of global esophageal,gastric,and liver cancer cases respectively,and 42.1%,39.4%,and 41.7%of corresponding deaths.However,the ASRs for incidence and mortality for all three cancers declined significantly in China(2000–2018),with absolute case numbers decreasing for gastric and esophageal cancers during 2010–2022.Age-specific analysis revealed most pronounced declines in incidence and mortality in populations under 40 years old,with AAPCs of less than–6.0%for esophageal cancer,around–4.0%for gastric cancer,and approximately–2.0%for liver cancer.Conclusions China has achieved remarkable progress in controlling esophageal,gastric and liver cancers,yet these malignancies remain major public health challenges.Future efforts should intensify existing prevention measures while expanding screening programs,particularly for aging populations.These findings offer valuable insights for regions undergoing similar epidemiological transitions. 展开更多
关键词 Esophageal cancer Gastric cancer Liver cancer Global burden TRENDS Average annual percent change
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Burden of Headache Disorders in China and its Provinces,1990-2021 被引量:1
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作者 Zhe Liu Xuehua Hu +5 位作者 Lin Yang Jinlei Qi Jiangmei Liu Lijun Wang Maigeng Zhou Peng Yin 《Biomedical and Environmental Sciences》 2025年第5期547-556,共10页
Objective To analyze the prevalence and burden of headache disorders in China and its provinces from 1990 to 2021.Methods Using data from the Global Burden of Disease Study(GBD)2021,the number of prevalent cases,preva... Objective To analyze the prevalence and burden of headache disorders in China and its provinces from 1990 to 2021.Methods Using data from the Global Burden of Disease Study(GBD)2021,the number of prevalent cases,prevalence rate,disability-adjusted life years(DALYs),and age-standardized DALY rates were analyzed by sex,age group,and province for headache disorders and their subtypes(migraine and tension-type headache[TTH])between 1990 and 2021.Percentage changes during this period were also estimated.Results In 2021,approximately 426 million individuals in China were affected by headache disorders,with an age-standardized prevalence rate of 27,582.61/100,000.The age-standardized DALY rate for all headache disorders was 487.15/100,000.Between 1990 and 2021,the number of prevalent cases increased by 37.78%,while the prevalence of all headache disorders,migraine,and TTH increased by 6.92%,7.57%,and 7.86%,respectively.The highest prevalence was observed in the 30-34 age group(39,520.60/100,000).Migraine accounted for a larger proportion of DALYs attributable to headache disorders,whereas TTH has a greater impact on its prevalence.In 2021,the highest age-standardized DALY rates for headache disorders were observed in Heilongjiang(617.85/100,000)and Shanghai(542.86/100,000).Conclusion The prevalence of headache disorders is increasing in China.Effective health education,improve diagnosis and treatment are essential,particularly for middle-aged working populations and women of childbearing age. 展开更多
关键词 Headache disorders MIGRAINE Tension-type headache Global burden of disease study
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Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time 被引量:1
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作者 Hao YOU Xinlong CHANG Jiufen ZHAO 《Chinese Journal of Aeronautics》 2025年第1期491-506,共16页
To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D lea... To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law. 展开更多
关键词 Three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode
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The telomere-to-telomere gap-free genome assembly of Juglans sigillata 被引量:1
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作者 Delu Ning Tao Wu +7 位作者 Wenlong Lei Shengcheng Zhang Ting Ma Li Pan Liangjun Xiao Noor-ul-Ain Xingtan Zhang Fuliang Cao 《Horticultural Plant Journal》 2025年第4期1551-1563,共13页
Juglans sigillata is an economically valuable nut crop renowned for its nutritional richness,including essential nutrients,antioxidants,and healthy fats,which boost human cardial,brain and gut health.Despite its impor... Juglans sigillata is an economically valuable nut crop renowned for its nutritional richness,including essential nutrients,antioxidants,and healthy fats,which boost human cardial,brain and gut health.Despite its importance,the lack of a complete genome assembly has been a stumbling block in its biological breeding process.Therefore,we generated deep coverage ultralong Oxford Nanopore Technology(ONT)and PacBio HiFi reads to construct a telomere-to-telomere(T2T)genome assembly.The final assembly spans 537.27 Mb with no gaps,demonstrating a remarkable completeness of 98.1%.We utilized a combination of transcriptome data and homologous proteins to annotate the genome,identifying 36018 protein-coding genes.Furthermore,we profiled global cytosine DNA methylations using ONT sequencing data.Global methylome analysis revealed high methylation levels in transposable element(TE)-rich chromosomal regions juxtaposed with comparatively lower methylation in gene-rich areas.By integrating a detailed multi-omics data analysis,we obtained valuable insights into the mechanism underlying endopleura coloration.This investigation led to the identification of eight candidate genes(e.g.ANR)involved in anthocyanin biosynthesis pathways,which are crucial for the development of color in plants.The comprehensive genome assembly and the understanding of the genetic basis of important traits like endopleura coloration will open avenues for more efficient breeding programs and improved crop quality. 展开更多
关键词 Juglans sigillata Telomere-to-telomere(T2T)genome assembly Global methylation Endopleura color
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High-Priority Actions to Improve Carbon Sequestration Potential for Mining Ecological Restoration in China 被引量:1
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作者 Fu Chen Yanfeng Zhu +3 位作者 Yinli Bi Yongjun Yang Jing Ma Suping Peng 《Engineering》 2025年第4期16-21,共6页
1.Introduction Changes in land use are key factors promoting global climate change,and the side effects of mining activity that destroy the soil,vegetation,and biodiversity lead to imbalanced carbon cycling in terrest... 1.Introduction Changes in land use are key factors promoting global climate change,and the side effects of mining activity that destroy the soil,vegetation,and biodiversity lead to imbalanced carbon cycling in terrestrial ecosystems. 展开更多
关键词 biodiversity impairment land use changes soil destruction global climate changeand mining activity land use vegetation loss imbalanced carbon cycling
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Stronger together: perovskite/silicon tandem solar cells 被引量:1
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作者 Shenghan Wu Shengqiang Ren +1 位作者 Cong Chen Dewei Zhao 《Journal of Semiconductors》 2025年第5期5-7,共3页
Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell ... Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell industry has experienced unprecedented development. The full utilization of solar energy resources remains an urgent issue to be addressed. 展开更多
关键词 carbon neutrality renewable resource perovskite silicon tandem solar cells solar energy carbon peak global energy shortage problem solar cell
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A Review on Modeling Environmental Loading Effects and Their Contributions to Nonlinear Variations of Global Navigation Satellite System Coordinate Time Series 被引量:1
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作者 Zhao Li Weiping Jiang +3 位作者 Tonie van Dam Xiaowei Zou Qusen Chen Hua Chen 《Engineering》 2025年第4期26-37,共12页
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at... Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050. 展开更多
关键词 Environmental loading Global navigation satellite system Nonlinear variations Time series analysis Surface mass distribution Green’s function Spherical harmonic function
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Global Piecewise Analysis of HIV Model with Bi-Infectious Categories under Ordinary Derivative and Non-Singular Operator with Neural Network Approach
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作者 Ghaliah Alhamzi Badr Saad TAlkahtani +1 位作者 Ravi Shanker Dubey Mati ur Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期609-633,共25页
This study directs the discussion of HIV disease with a novel kind of complex dynamical generalized and piecewise operator in the sense of classical and Atangana Baleanu(AB)derivatives having arbitrary order.The HIV i... This study directs the discussion of HIV disease with a novel kind of complex dynamical generalized and piecewise operator in the sense of classical and Atangana Baleanu(AB)derivatives having arbitrary order.The HIV infection model has a susceptible class,a recovered class,along with a case of infection divided into three sub-different levels or categories and the recovered class.The total time interval is converted into two,which are further investigated for ordinary and fractional order operators of the AB derivative,respectively.The proposed model is tested separately for unique solutions and existence on bi intervals.The numerical solution of the proposed model is treated by the piece-wise numerical iterative scheme of Newtons Polynomial.The proposed method is established for piece-wise derivatives under natural order and non-singular Mittag-Leffler Law.The cross-over or bending characteristics in the dynamical system of HIV are easily examined by the aspect of this research having a memory effect for controlling the said disease.This study uses the neural network(NN)technique to obtain a better set of weights with low residual errors,and the epochs number is considered 1000.The obtained figures represent the approximate solution and absolute error which are tested with NN to train the data accurately. 展开更多
关键词 HIV infection model qualitative scheme approximate solution piecewise global operator neural network
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Evolutionary Particle Swarm Optimization Algorithm Based on Collective Prediction for Deployment of Base Stations
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作者 Jiaying Shen Donglin Zhu +5 位作者 Yujia Liu Leyi Wang Jialing Hu Zhaolong Ouyang Changjun Zhou Taiyong Li 《Computers, Materials & Continua》 SCIE EI 2025年第1期345-369,共25页
The wireless signals emitted by base stations serve as a vital link connecting people in today’s society and have been occupying an increasingly important role in real life.The development of the Internet of Things(I... The wireless signals emitted by base stations serve as a vital link connecting people in today’s society and have been occupying an increasingly important role in real life.The development of the Internet of Things(IoT)relies on the support of base stations,which provide a solid foundation for achieving a more intelligent way of living.In a specific area,achieving higher signal coverage with fewer base stations has become an urgent problem.Therefore,this article focuses on the effective coverage area of base station signals and proposes a novel Evolutionary Particle Swarm Optimization(EPSO)algorithm based on collective prediction,referred to herein as ECPPSO.Introducing a new strategy called neighbor-based evolution prediction(NEP)addresses the issue of premature convergence often encountered by PSO.ECPPSO also employs a strengthening evolution(SE)strategy to enhance the algorithm’s global search capability and efficiency,ensuring enhanced robustness and a faster convergence speed when solving complex optimization problems.To better adapt to the actual communication needs of base stations,this article conducts simulation experiments by changing the number of base stations.The experimental results demonstrate thatunder the conditionof 50 ormore base stations,ECPPSOconsistently achieves the best coverage rate exceeding 95%,peaking at 99.4400%when the number of base stations reaches 80.These results validate the optimization capability of the ECPPSO algorithm,proving its feasibility and effectiveness.Further ablative experiments and comparisons with other algorithms highlight the advantages of ECPPSO. 展开更多
关键词 Particle swarm optimization effective coverage area global optimization base station deployment
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