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Reconstructing historical forest fire risk in the non-satellite era using the improved forest fire danger index and long short-term memory deep learning-a case study in Sichuan Province,southwestern China

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Forest Ecosystems 2024年第1期11卷 87-99页

作者： Yuwen Peng Huiyi Su min sun mingshi Li Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037China College of Forestry Nanjing Forestry UniversityNanjing 210037China

Historical forest fire risk databases are vital for evaluating the effectiveness of past forest management approaches,enhancing forest fire warnings and emergency response capabilities,and accurately budgeting potential carbon emissions resulting from fires.However,due to the unavailability of spatial information technology,such databases are extremely difficult to build reliably and completely in the non-satellite era.This study presented an improved forest fire risk reconstruction framework that integrates a deep learning-based time series prediction model and spatial interpolation to address the challenge in Sichuan Province,southwestern China.First,the forest fire danger index(FFDI)was improved by supplementing slope and aspect information.We compared the performances of three time series models,namely,the autoregressive integrated moving average(ARIMA),Prophet and long short-term memory(LSTM)in predicting the modified forest fire danger index(MFFDI).The bestperforming model was used to retrace the MFFDI of individual stations from 1941 to 1970.Following this,the Anusplin spatial interpolation method was used to map the distributions of the MFFDI at five-year intervals,which were then subjected to weighted overlay with the distance-to-river layer to generate forest fire risk maps for reconstructing the forest fire danger database.The results revealed LSTM as the most accurate in fitting and predicting the historical MFFDI,with a fitting determination coefficient(R^2)of 0.709,mean square error(MSE)of0.047,and validation R^2 and MSE of 0.508 and 0.11,respectively.Independent validation of the predicted forest fire risk maps indicated that 5 out of 7 historical forest fire events were located in forest fire-prone areas,which is higher than the results determined from the original FFDI(2 out of 7).This proves the effectiveness of the improved MFFDI and indicates a high level of reliability of the historical forest fire risk reconstruction method proposed in this study.

关键词： Forest fire risk reconstruction MFFDI Time series models LSTM ARIMA Prophet Anusplin

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Protective mechanism of Coprinus comatus polysaccharide on acute alcoholic liver injury in mice,the metabolomics and gut microbiota investigation

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Food Science and Human Wellness 2024年第1期13卷 401-413页

作者： Jinyan Yu Jianguang sun min sun Weidong Li Dongmei Qi Yongqing Zhang Chunchao Han School of Pharmacy Shandong University of Traditional Chinese MedicineJinan 250355China Hepatology Department of Affiliated Hospital of Shandong University of Traditional Chinese Medicine Jinan 250355China Experimental center Shandong University of Traditional Chinese MedicineJinan 250355China

Coprinus comatus polysaccharide(CCP)has significant hepatoprotective effect.To explore hepatoprotective mechanism of CCP,the study analyzed preventive effect of CCP on acute alcoholic liver injury in mice by histopathological examination and biochemical analysis.Simultaneously,hepatoprotective mechanism was also analyzed in conjunction with metabolomics and proliferation of gut microbiota.The results showed that CCP significantly decreased alanine aminotransferase(ALT),aspartate aminotransferase(AST)and triglyceride(TG)levels in serum of alcoholic liver disease(ALD)mice.Histopathological examination showed that CCP can significantly improve liver damage.Metabolomics results showed that there were significant differences in the level of metabolites in liver tissue of control group,ALD group and CCP group,including taurine,xanthosine,fumaric acid and arachidonic acid,among others.Metabolites pathways analysis showed that hepatoprotective effect of CCP was related to energy metabolism,biosynthesis of unsaturated fatty acids,amino acids metabolism and lipid metabolism.Additionally,CCP inhibited an increase in the number of Clostridium perfringens,Enterobacteriaceae and Enterococcus,and a decrease in the number of Lactobacillus and Bifidobacterium in the gut of ALD mice.All these findings suggested that CCP treatment reversed the phenotype of ethanol-induced liver injury and the associated metabolites pathways.

关键词： Coprinus comatus Polysaccharide Alcoholic liver disease Metabolomics Gut microbiota

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Observability of Periodically Switched Boolean Control Networks

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Journal of Systems Science & Complexity 2023年第3期36卷 985-1001页

作者： JIANG Chunfeng WANG Biao FU Shihua ZHAO Jianli sun min Department of Engineering University of SannioBenevento 82100Italy.Email:chunf jiang@*** School of Management Shandong UniversityJinan 250100China School of Mathematical Sciences Liaocheng UniversityLiaocheng 252000China School of Mathematics and Statistics Zaozhuang UniversityZaozhuang 277160China

In this paper,observability is studied for periodically switched Boolean control networks(PSBCNs),which are managed with periodic switching signal and consist of some Boolean control networks.Firstly,via semi-tensor product of matrices,PSBCNs are expressed as algebraic forms.Secondly,a parallel system is constructed by combining two same PSBCNs,based on which,the observability problem of the original PSBCN can be transformed into the set reachability problem of this parallel system.Then,two necessary and sufficient conditions are obtained to detect reachability of parallel systems and observability of PSBCNs.In addition,the proposed conditions are extended to the case of state constraints.Finally,a practical example and a numerical example are provided to illustrate the results.

关键词： Boolean control networks observability periodically switched systems semi-tensor product state constraints

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Mechanistic investigation on Ag-Cu_(2)O in electrocatalytic CO_(2) to CH_(4) by in situ/operando spectroscopic and theoretical analysis

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Journal of Energy Chemistry 2024年第1期88卷 521-531,I0012页

作者： min sun Luxiao Zhang Fuli Tian Jiaxin Li Yanqiu Lei Heng Zhang Lifeng Han Zhihua Guo Yonghui Gao Fenrong Liu Yan Wang Luhui Wang Shanghong Zeng School of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021Inner MongoliaChina Key Laboratory of Medicinal and Edible Plants Resources of Hainan Province Hainan Vocational University of Science and TechnologyHaikou 571126HainanChina State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030Inner MongoliaChina Zhejiang Key Laboratory of Petrochemical Environmental Pollution Control Zhejiang Ocean UniversityZhoushan 316022ZhejiangChina

Silver-copper electrocatalysts have demonstrated effectively catalytic performance in electroreduction CO_(2) toward CH_(4),yet a revealing insight into the reaction pathway and mechanism has remained elusive.Herein,we construct chemically bonded Ag-Cu_(2)O boundaries,in which the complete reduction of Cu_(2)O to Cu has been strongly impeded owing to the presence of surface Ag shell.The interfacial confinement effect helps to maintain Cu^(+)sites at the Ag-Cu_(2)O boundaries.Using in situ/operando spectroscopy and theoretical simulations,it is revealed that CO_(2) is enriched at the Ag-Cu_(2)O boundaries due to the enhanced physisorption and chemisorption to CO_(2),activating CO_(2) to form the stable intermediate^(*)CO.The boundaries between Ag shell and the Cu_(2)O mediate local^(*)CO coverage and promote^(*)CHO intermediate formation,consequently facilitating CO_(2)-to-CH_(4) conversion.This work not only reveals the structure-activity relationships but also offers insights into the reaction mechanism on Ag-Cu catalysts for efficient electrocatalytic CO_(2) reduction.

关键词： Ag shell Interfacial confinement effect Cu~+ Local*CO coverage CO_(2)reduction

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V0405 Dra: A New Deep and Low Mass Ratio Contact Binary with Extremely Fast Decrease in the Orbital Period

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Research in Astronomy and Astrophysics 2024年第6期24卷 289-295页

作者： Chao-Yue Li Lin-Qiao Jiang Jie Zheng Yi-Man Liu Xiao-Yu Long min sun Han-Lu Zhang Xiao-Man Tian School of Science Leshan Normal University Center for Applied Optics Research Leshan Normal University Key Laboratory of Detection and Application of Space Effect in Southwest Sichuan CAS Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences School of Aeronautics Shandong Jiaotong University

V0405 Dra is a W UMa-type binary star. Based on the TESS data, we have conducted an orbital period study and performed a light curve analysis for the system. The orbital period study reveals that the O-C curve for V0405 Dra exhibits secular decrease at an extremely high rate of d P/dt =-2.71 × 10-6day year-1, along with periodic variations characterized by an amplitude of A3= 0.0032 day and a period of P3= 1.413 years. The orbital periodic change is possibly due to the light-travel time effect resulting from an additional third body in the system, for which we estimate a minimum mass of M3= 0.77M⊙. By employing the 2013 version of the Wilson-Devinney（W-D） method to synthesize a light curve, we derived photometric solutions indicating that V0405 Dra is a new deep（ f = 68.7%） and low-mass ratio（q = 0.175） contact binary. The fast decrease in its orbital period is likely caused by mass transfer from the more massive primary star to the less massive secondary star, or due to angular momentum loss. With further mass transfer and loss of angular momentum, the binary will gradually evolve into a tighter contact configuration, eventually leading to a merger into a single star, following the evolutionary paths suggested for such deep and low mass ratio contact binaries.

关键词： (stars:) binaries (including multiple): close (stars:) binaries: eclipsing stars: individual (V0405 Dra)

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Genetic lineage tracing identifies adaptive mechanisms of pancreatic islet β cells in various mouse models of diabetes with distinct age of initiation

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Science China(Life Sciences) 2024年第3期67卷 504-517页

作者： Qi Fu Yu Qian Hemin Jiang Yunqiang He Hao Dai Yang Chen Zhiqing Xia Yucheng Liang Yuncai Zhou Rui Gao Shuai Zheng Hui Lv min sun Kuanfeng Xu Tao Yang Department of Endocrinology the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

During the pathogenesis of type 1 diabetes(T1D) and type 2 diabetes(T2D), pancreatic islets, especially the β cells, face significant challenges. These insulin-producing cells adopt a regeneration strategy to compensate for the shortage of insulin, but the exact mechanism needs to be defined. High-fat diet(HFD) and streptozotocin(STZ) treatment are well-established models to study islet damage in T2D and T1D respectively. Therefore, we applied these two diabetic mouse models, triggered at different ages, to pursue the cell fate transition of isletβ cells. Cre-LoxP systems were used to generate islet cell type-specific(α, β, or δ) green fluorescent protein(GFP)-labeled mice for genetic lineage tracing, thereinto β-cell GFP-labeled mice were tamoxifen induced. Single-cell RNA sequencing(scRNA-seq) was used to investigate the evolutionary trajectories and molecular mechanisms of the GFP-labeled β cells in STZ-treated mice. STZ-induced diabetes caused extensive dedifferentiation of β cells and some of which transdifferentiated into α or δ cells in both youth-and adulthood-initiated mice while this phenomenon was barely observed in HFD models. β cells in HFD mice were expanded via self-replication rather than via transdifferentiation from α or δ cells, in contrast, α or δ cells were induced to transdifferentiate into β cells in STZ-treated mice(both youthand adulthood-initiated). In addition to the re-dedifferentiation of β cells, it is also highly likely that these “α or δ” cells transdifferentiated from pre-existing β cells could also re-trans-differentiate into insulin-producing β cells and be beneficial to islet recovery. The analysis of ScRNA-seq revealed that several pathways including mitochondrial function, chromatin modification, and remodeling are crucial in the dynamic transition of β cells. Our findings shed light on how islet β cells overcome the deficit of insulin and the molecular mechanism of islet recovery in T1D and T2D pathogenesis.

关键词： islet regeneration lineage tracing high fat diet(HFD) streptozotocin(STZ)

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城乡关系视域下农村集体经济的实践类型及其运作逻辑

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社会科学 2024年第3期 153-165页

作者：孙敏湖南师范大学历史文化学院

不同地区劳动力与土地剥离程度以及工商资本与集体土地的结合程度的巨大差异在我国形塑了三种农村集体经济类型:紧密型城乡关系支配的分配型集体经济、过渡型城乡关系主导的中介型集体经济和松散型城乡关系影响的社会型集体经济。不同... 详细信息

不同地区劳动力与土地剥离程度以及工商资本与集体土地的结合程度的巨大差异在我国形塑了三种农村集体经济类型:紧密型城乡关系支配的分配型集体经济、过渡型城乡关系主导的中介型集体经济和松散型城乡关系影响的社会型集体经济。不同类型集体经济在实践中遵循不同的运作逻辑且呈现出发展路径的区域差异:分配型集体经济建立在工商资本持续下乡的基础上,集体组织与集体成员围绕集体收益分配进行博弈;中介型集体经济随本地农业现代转型应运而生,集体组织与承包者、经营者围绕农业生产效率最大化形成在地化互动;社会型集体经济在相对贫困持续约束的背景下形成,围绕农村公共品供给与服务展开社会治理成为其核心内容。对中国农村集体经济丰富的实践进行类型化提炼与分析,在中观层面,能为不同地区农村集体经济创新在地化发展模式提供理论依据,还能进一步展现农村集体经济助力中国迈向共同富裕的价值内涵。

关键词：农村集体经济城乡关系共同富裕理想类型

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基于激光雷达与遥感数据的地理空间要素识别方法

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激光杂志 2024年第2期45卷 245-249页

作者：孙敏长春工程学院长春130021

通过地理空间要素识别实现地理测绘和环境有效监测,提出基于激光雷达与遥感数据的地理空间要素识别方法。采用激光雷达的遥感监测方法实现对地理空间特征的对象集变化检测,根据地理空间测绘对象的纹理、形状、空间关系,采用遥感数据融... 详细信息

通过地理空间要素识别实现地理测绘和环境有效监测,提出基于激光雷达与遥感数据的地理空间要素识别方法。采用激光雷达的遥感监测方法实现对地理空间特征的对象集变化检测,根据地理空间测绘对象的纹理、形状、空间关系,采用遥感数据融合和空间信息表达方法实现对地理空间要素特征的专家知识融合,构建地理空间要素识别的遥感专家数据库。仿真结果表明,采用该方法进行地理空间要素识别的决策融合性较好。该方法也实现了对土地利用自然特征变化的检测,使得识别准确率的最大值可达到0.925,且识别耗时始终处于2.5 s以下。

关键词：激光雷达遥感数据地理空间要素识别遥感专家数据库

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miR-410-3p通过靶向YAP1调节IL-22诱导的人角质形成细胞增殖和凋亡

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中国免疫学杂志 2024年第2期40卷 261-265,272页

作者：孙敏任虹连云港市第一人民医院皮肤科连云港222000

目的:探究miR-410-3p在银屑病中的表达及其对角质形成细胞增殖和凋亡的影响及机制。方法:收集12例寻常型银屑病患者和12例健康志愿者空腹静脉血,qRT-PCR检测血清miR-410-3p表达。将常规培养的人角质形成细胞HaCaT分为:对照组、IL-22组、... 详细信息

目的:探究miR-410-3p在银屑病中的表达及其对角质形成细胞增殖和凋亡的影响及机制。方法:收集12例寻常型银屑病患者和12例健康志愿者空腹静脉血,qRT-PCR检测血清miR-410-3p表达。将常规培养的人角质形成细胞HaCaT分为:对照组、IL-22组、miR-NC组和miR-410-3p组。后3组使用100 ng/ml IL-22刺激24 h,体外建立银屑病模型。miRNC组和miR-410-3p组加入IL-22前48 h分别转染miR-NC和miR-410-3p,对照组不进行任何处理。CCK-8分析细胞活力,BrdU检测细胞增殖,流式细胞术检测细胞凋亡,qRT-PCR检测miR-410-3p和YAP1 mRNA表达,Western blot分析YAP1蛋白表达。Starbase软件和双荧光素酶报告基因分析miR-410-3p和YAP1的靶向关系。转染miR-410-3p的HaCaT银屑病细胞模型中同时过表达YAP1,检测细胞活力和凋亡。结果:miR-410-3p在银屑病患者血清中的表达显著低于健康志愿者(P<0.05)。与对照组相比,IL-22组miR-410-3p表达降低,YAP1 mRNA和蛋白表达增加,细胞活力增强,BrdU阳性细胞增多,凋亡率降低(均P<0.05);与IL-22组相比,miR-410-3p组miR-410-3p表达增加,YAP1 mRNA和蛋白表达减少,细胞活力减弱,BrdU阳性细胞减少,凋亡率升高(均P<0.05)。此外,本实验证实miR-410-3p与YAP1存在靶向结合关系,过表达YAP1可逆转miR-410-3p对IL-22诱导的HaCaT细胞增殖和凋亡的影响。结论:miR-410-3p在银屑病患者中表达减少,上调其表达可通过靶向YAP1抑制IL-22诱导的角质形成细胞增殖,促进细胞凋亡。

关键词： miR-410-3p 银屑病角质形成细胞增殖凋亡 YAP1

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Synthesis of IM-5 Zeolite by Template Pre-Reaction

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China Petroleum Processing & Petrochemical Technology 2021年第2期23卷 77-83页

作者： sun min State Key Laboratory of Catalytic Materials and Reaction Engineering Research Institute of Petroleum ProcessingSINOPECBeijing 100083

IM-5 zeolite was synthesized by hydrothermal crystallization method with 1,5-bis(N-methylpyrrolidinium)pentane bromide using the precursors N-methylpyrrolidine and 1,5-dibromopentane as raw materials of template after pre-reaction,and then aluminum,alkali,water and silicon sources were added into the reaction system.The effects of the proportion of precursors and other materials and the reaction conditions on the crystallinity,crystal morphology and pore structure of the synthesized zeolites were systematically investigated,which provided the basic data for industrial production.The physical properties of the synthesized samples were analyzed by XRD,SEM,and N2 adsorptiondesorption techniques,and the catalytic performance of the samples was evaluated.The results show that IM-5 zeolite can be synthesized effectively by using the template pre-reaction method,and its physical properties and catalytic activity in catalytic alkylation of benzene and methanol are comparable to those of industrial samples synthesized by traditional method.

关键词： IM-5 zeolite template pre-reaction catalytic performance

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