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Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： Hai-Jun Li ying-Quan Peng Wei Chao Yu-Feng zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still unknown.In this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion bubbles.In this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after inflation.The QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase transition.We consider a general case in which the axion bubbles are formed with the bubble effective angleθeff∈(0,π],leading to the minimum PBH mass∼O(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼O(10^(16))GeV.The PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020

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Plant Diversity 2024年第1期46卷 70-77页

作者： Shi-Guang Wei Lin Li Kun-Dong Bai Zhi-Feng Wen jing-Gang zhou Qin Lin Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilin 541004GuangxiChina School of Life&Environmental Sciences Guilin University of Electronic TechnologyGuilin 541004GuangxiChina Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin Guilin 541004GuangxiChina Key Laboratory of Vegetation Restoration and Management of South China Botanical Garden of Degraded Ecosystems Chinese Academy of SciencesGuangzhou 510650GuangdongChina Center of Plant Ecology Core Botanical GardensChinese Academy of SciencesGuangzhou 510650GuangdongChina

Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.

关键词： Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest

Cerebral furin deficiency causes hydrocephalus in mice

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Genes & Diseases 2024年第3期11卷 438-451页

作者： Shiqi Xie Xiaoyong Xie jing Tang Biao Luo Jian Chen Qixin Wen Jianrong zhou Guojun Chen Nursing College Chongqing Medical UniversityChongqing 400016China Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of Major Neurological and Mental DisordersChongqing Key Laboratory of NeurologyChongqing 400016China

Furin is a pro-protein convertase that moves between the trans-Golgi network and cell surface in the secretory pathway.We have previously reported that cerebral overexpres-sion of furin promotes cognitive functions in mice.Here,by generating the brain-specific furin conditional knockout(ckO)mice,we investigated the role of furin in brain development.We found that furin deficiency caused early death and growth retardation.Magnetic resonance im-aging showed severe hydrocephalus.In the brain of furin cko mice,impaired ciliogenesis and the derangement of microtubule structures appeared along with the down-regulated expres-sion of RAB28,a ciliary vesicle protein.In line with the widespread neuronal loss,ependymal cell layers were damaged.Further proteomics analysis revealed that cell adhesion molecules including astrocyte-enriched ITGB8 and BCAR1 were altered in furin cKO mice;and astrocyte overgrowth was accompanied by the reduced expression of sox9,indicating a disrupted differ-entiation into ependymal cells.Together,whereas alteration of RAB28 expression correlated with the role of vesicle trafficking in ciliogenesis,dysfunctional astrocytes might be involved in ependymal damage contributing to hydrocephalus in furin ckO mice.The structural and mo-lecular alterations provided a clue for further studying the potential mechanisms of furin.

关键词： Astrocyte Ciliogenesis Conditionalknockout Ependymal Furin Hydrocephalus Proteomics

Temporal and spatial evolution of global major grain trade patterns

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Journal of Integrative Agriculture 2024年第3期23卷 1075-1086页

作者： Ziqi Yin Jiaxuan Hu jing Zhang Xiangyang zhou Lingling Li Jianzhai Wu Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081China Institute of Scientific and Technical Information of China Beijing 100038China Zibo Agricultural Science Research Institute Zibo 255000China Zibo Institute for Digital Agriculture and Rural Research Zibo 255000China

The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain trade from 1990 to 2020, focusing on network topology, centrality ranking, and community structure. There are three major findings. First, the global major grain trade network has expanded in scale, with a growing emphasis on diversification and balance. During the study period, the United States, Canada, China, and Brazil were the core nodes of the network. Grain-exporting countries were mainly situated in Asia, the Americas, and Europe, and importing countries in Asia, Africa, and Europe. Second, a significant increase in the number of high centrality countries with high export capacity occurred, benefiting from natural advantages such as fertile land and favorable climates. Third, the main global grain trade network is divided into four communities, with the Americas-Europe community being the largest and most widespread. The formation of the community pattern was influenced by geographic proximity, driven by the core exporting countries. Therefore, the world needs to enhance the existing trade model, promote the multi-polarization of the grain trade network, and establish a global vision for the future community. Countries and regions should participate actively in global grain trade security governance and institutional reform, expand trade links with other countries, and optimize import and export policies to reduce trade risks.

关键词： grain trade pattern evolution complex network

Fast,simple,efficient Agrobacterium rhizogenes-mediated transformation system to non-heading Chinese cabbage with transgenic roots

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Horticultural Plant Journal 2024年第2期10卷 450-460页

作者： Huiyu Wang Yushan Zheng Qian zhou ying Li Tongkun Liu Xilin Hou State Key Laboratory of Crop Genetics&Germplasm Enhancement Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(East China)Ministry of Agriculture and Rural Affairs of ChinaEngineering Research Center of Germplasm Enhancement and Utilization of Horticultural CropsMinistry of Education of ChinaNanjing Agricultural UniversityNanjingJiangsu 210095China Nanjing Suman Plasma Engineering Research Institute Nanjing Agricultural UniversityNanjingJiangsu 210095China

Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation efficiency limit gene function research on non-heading Chinese cabbage. Agrobacterium rhizogenes-mediated(ARM) transgenic technology is a rapid and effective transformation method that has not yet been established for non-heading Chinese cabbage plants. Here, we optimized conventional ARM approaches(one-step and two-step transformation methods) suitable for living non-heading Chinese cabbage plants in nonsterile environments. Transgenic roots in composite non-heading Chinese cabbage plants were identified using phenotypic detection, fluorescence observation, and PCR analysis. The transformation efficiency of a two-step method on four five-day-old non-heading Chinese cabbage seedlings(Suzhouqing, Huangmeigui, Wuyueman, and Sijiu Caixin) was 43.33%-51.09%, whereas using the stout hypocotyl resulted in a transformation efficiency of 54.88% for the 30-day-old Sijiu Caixin.The one-step method outperformed the two-step method;the transformation efficiency of different varieties was above 60%, and both methods can be used to obtain transgenic roots for functional studies within one month. Finally, optimized ARM transformation methods can easily,quickly, and effectively produce composite non-heading Chinese cabbage plants with transgenic roots, providing a reliable foundation for gene function research and non-heading Chinese cabbage genetic improvement breeding.

关键词： Agrobacterium rhizogenes Non-heading Chinese cabbage Transgenic roots Composite plant Transformation efficiency

Collaborative positioning for swarms:A brief survey of vision,LiDAR and wireless sensors based methods

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Defence Technology（防务技术） 2024年第3期33卷 475-493页

作者： Zeyu Li Changhui Jiang Xiaobo Gu ying Xu Feng zhou Jianhui Cui College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao266590China Geoloc Laboratory Universite Gustave EiffelParis77454France School of Automation Guangdong University of TechnologyGuangzhou510006China

As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other agents.By receiving spatial information from both its environment and other agents,an agent can use various methods and sensor types to localize itself.With its high flexibility and robustness,collaborative positioning has become a widely used method in both military and civilian applications.This paper introduces the basic fundamental concepts and applications of collaborative positioning,and reviews recent progress in the field based on camera,LiDAR(Light Detection and Ranging),wireless sensor,and their integration.The paper compares the current methods with respect to their sensor type,summarizes their main paradigms,and analyzes their evaluation experiments.Finally,the paper discusses the main challenges and open issues that require further research.

关键词： Collaborative positioning Vision LiDAR Wireless sensors Sensor fusion

Guiding function of positron emission tomographycomputed tomography examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 693-699页

作者： Xuan Zhang Qi-Han Guo Rui Liu jing Li ying-Chao Li Jian-Min Ma Beijing Ophthalmology and Visual Sciences Key Laboratory Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Tai’an City Central Hospital Qingdao UniversityTai’an 271000Shandong ProvinceChina

AIM:To explore the role of positron emission tomographycomputed tomography(PET-CT)examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma(OAML).METHODS:The general clinical data,postoperative PET-CT results,treatment regimens,and the prognosis of 21 histopathologically confirmed OAML patients between October 2017 and September 2021 were collected.Among the 21 patients,five patients underwent surgical treatment alone,13 patients underwent surgical treatment combined with radiotherapy,and three patients underwent surgical treatment combined with chemotherapy.RESULTS:The follow-up period ranged from 8 to 79mo,with four cases of recurrence and no deaths.Through PETCT examination,two patients exhibited both local ocular metabolic elevation and systemic metastasis,and one of these patients had cervical lymph node metastasis,while the other had submandibular and parotid gland metastasis.Nine patients showed only local ocular metabolic elevation,while 10 patients had no abnormal metabolic activity locally.CONCLUSION:PET-CT examination plays a crucial role in detecting residual lesions and recurrence following tumor resection,aiding in precise disease staging,and facilitating the development of personalized treatment plans,ultimately improving patient prognosis.

关键词： ocular adnexal mucosa associated lymphoid tissue lymphoma positron emission tomographycomputed tomography ocular tumors

Unlock the full potential of carbon cloth-based scaffolds towards magnesium metal storage via regulation on magnesiophilicity and surface geometric structure

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Journal of Energy Chemistry 2024年第3期90卷 423-434,I0010页

作者： jing Liu Min Wang Zhonghua Zhang Jinlei Zhang Yitao He Zhenfang zhou Guicun Li College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042ShandongChina Department of Pharmacy Jining Medical UniversityRizhao 276826ShandongChina Department of Energy and Power Engineering School of Energy and EnvironmentAnhui University of TechnologyMa’anshan 243000AnhuiChina

The development of rechargeable magnesium(Mg) batteries is of practical significance to upgrade the electric energy storage devices due to exceptional capacity and abundant resources of Mg-metal anode.However,the reversible Mg electrochemistry suffers from unsatisfied rate capability and lifespan,mainly caused by non-uniform distribution of electrodeposits.In this work,a fresh design concept of threedimensional carbon cloths scaffolds is proposed to overcome the uncontrollable Mg growth via homogenizing electric field and improving magnesiophilicity.A microscopic smooth and nitrogen-containing defective carbonaceous layer is constructed through a facile pyrolysis of ZIF8 on carbon cloths.As revealed by finite element simulation and DFT calculation results,the smooth surface endows with uniform electric field distribution and simultaneously the nitrogen-doping species enable good magnesiophilicity of scaffolds.The fine and uniform Mg nucleus as well as the inner electrodeposit behavior are also disclosed.As a result,an exceptional cycle life of 500 cycles at 4.0 mA cm^(-2) and 4.0 mA h cm^(-2) is firstly realized to our best knowledge.Besides,the functional scaffolds can be cycled for over 2200 h at 2.0 mA cm^(-2) under a normalized capacity of 5.0 mA h cm^(-2),far exceeding previous results.This work offers an effective approach to enable the full potential of carbon cloths-based scaffolds towards metal storage for next generation battery applications.

关键词： Magnesium metal anodes Electrodeposition Heterogeneous nucleation

Towards accurate mapping of loess waterworn gully by integrating google earth imagery and DEM using deep learning

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International Soil and Water Conservation Research 2024年第1期12卷 13-28页

作者： Rong Chen Yi zhou Zetao Wang ying Li Fan Li Feng Yang School of Geography and Tourism Shaanxi Normal UniversityXi'an710119China National Experiment and Teaching Demonstration Center for Geography Xi'an710119China SuperMap Software Co. Ltd.Beijing100015China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Accurate mapping of loess waterworn gully(LWG)is essential to further study gully erosion and geomorphological evolution for the Chinese Loess Plateau(CLP).Due to the vertical joint and collapsibility of loess,LWGs have the characteristics of zigzag and unique slope abruptness under synthetic action of hydraulic force and gravity.This forces existing LWG mapping methods to either focus on the improvement of mapping accuracy or center on the increase of mapping efficiency.However,simultaneously achieving accurate and efficient mapping of LWG is still in its infancy under complex topographic conditions.Here,we proposed a method that innovatively integrates the loess slope abruptness feature into an improved deep learning semantic segmentation framework for LWG mapping using 0.6 m Google imagery and 5 m DEM data.We selected four study areas representing typical loess landforms to test the performance of our method.The proposed method can achieve satisfactory mapping results,with the F1 score,mean Intersection-over-Union(mIoU),and overall accuracy of 90.5%,85.3%,and 92.3%,respectively.In addition,the proposed model also showed significant accuracy improvement by inputting additional topographic information(especially the slope of slope).Compared with existing algorithms(Random forests,original DeepLabV3+,and Unet),the proposed approach in this study achieved a better accuracy-efficiency trade-off.Overall,the method can ensure high accuracy and efficiency of the LWG mapping for different loess landform types and can be extended to study various loess gully mapping and water and soil conservation.

关键词： Loess waterworn gully Topographic information Mapping Deep learning Soil erosion Loess plateau