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Characterizing the spatiotemporal variations of evapotranspiration and aridity index in mid-western China from 2001 to 2016

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Journal of Arid Land 2021年第12期13卷 1230-1243页

作者： MU Le LU Yixiao LIU Minguo YANG Huimin feng qisheng State Key Laboratory of Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020China

Mid-western China is one of the most sensitive and fragile areas on the Earth.Evapotranspiration(ET)is a key part of hydrological cycle in these areas and is affected by both global climate change and human activities.The dynamic changes in ET and potential evapotranspiration(PET),which can reflect water consumption and demand,are still unclear,and there is a lack of predictive capacity on drought severity.In this study,we used global MODIS(moderate-resolution imaging spectroradiometer)terrestrial ET(MOD16)products,Morlet wavelet analysis,and simple linear regression to investigate the spatiotemporal variations of ET,PET,reference ET(ET0),and aridity index(AI)in mid-western pastoral regions of China(including Gansu Province,Qinghai Province,Ningxia Hui Autonomous Region,and part of Inner Mongolia Autonomous Region)from 2001 to 2016.The results showed that the overall ET gradually increased from east to southwest in the study area.Actual ET showed an increasing trend,whereas PET tended to decrease from 2001 to 2016.The change in ET was affected by vegetation types.During the study period,the average annual ET0 and AI tended to decrease.At the monthly scale within a year,AI value decreased from January to July and then increased.The interannual variations of ET0 and AI showed periodicity with a main period of 14 a,and two other periodicities of 11 and 5 a.This study showed that in recent years,drought in these pastoral regions of mid-western China has been alleviated.Therefore,it is foreseeable that the demand for irrigation water for agricultural production in these regions will decrease.

关键词： evapotranspiration aridity index climate change human activities vegetation cover arid areas

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Changes in global potential vegetation distributions from 1911 to 2000 as simulated by the Comprehensive Sequential Classification System approach

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Chinese Science Bulletin 2012年第11期57卷 1298-1310页

作者： LIANG TianGang feng qisheng CAO JianJun XIE HongJie LIN HuiLong ZHAO Jun REN JiZhou State Key Laboratory of Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 770020 China State Key Laboratory for Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China Basic Geographic Information Center of Gansu Province Lanzhou 730000China University of Texas at San Antonio Department of Geological SciencesLaboratory for Remote Sensing and GeoinformaticsSan AntonioTexas78249USA College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China

Vegetation classification models play an important role in studying the response of the terrestrial ecosystem to global climate change. In this paper, we study changes in global Potential Natural Vegetation (PNV) distributions using the Comprehensive Sequential Classification System (CSCS) approach, a technique that combines geographic information systems. Results indicate that on a global scale there are good agreements among maps produced by the CSCS method and the globally well-accepted Holdridge Life Zone (HLZ) and BIOME4 PNV models. The potential vegetation simulated by the CSCS approach has 6 major latitudinal zones in the northern hemisphere and 2 in the southern hemisphere. In mountainous areas it has obvious altitudinal distribution characteristics due to topographic effects. The distribution extent for different PNV classes at various periods has different characteristics. It had a decreasing trend for the tundra and alpine steppe, desert, sub-tropical forest and tropical forest categories, and an increasing trend for the temperate forest and grassland vegetation categories. The simulation of global CSCS-based PNV classes helps to understand climate-vegetation relationships and reveals the dynamics of potential vegetation distributions induced by global changes. Compared with existing statistical and equilibrium models, the CSCS approach provides similar mapping results for global PNV and has the advantage of improved simulation of grassland classes.

关键词：植被分布分类系统模拟全球气候变化亚热带森林陆地生态系统地理信息系统高山草原

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Modification of Hydration Resistance of SrO with ZrO_(2) Addition

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China's Refractories 2022年第4期31卷 16-21页

作者： CHEN Guangyao LIU Jian YU Feihai HOU Xiao feng qisheng PENG Jun WANG Enhui HOU Xinmei LU Xionggang LI Chonghe State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Shanghai Special Casting Engineering Technology Research Center Shanghai 201605China China Northwest Architecture Design and Research Institute Co. LtdXi’an 710018China Beijing Advanced Innovation Center for Materials Genome Engineering Collaborative Innovation Center of Steel TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Considering the high melting point and high stability of SrO,it has potential applications in the field of the preparation of titanium alloys.To improve the hydration resistance,SrO samples with different ZrO_(2)additions were fabricated after firing at 1750℃for 6 h.The phase,the microstructure,and the hydration resistance of the samples were researched.The results show that the sample with 33 mol%ZrO_(2)addition possesses good hydration resistance with the mass gain after hydration for 13 days of less than 0.42 mass%.The SrO crucible with 33 mol%ZrO_(2)addition does not react with TiNi alloy melt during melting,which provides a support for searching new refractories with good hydration resistance for induction melting titanium alloys.

关键词： strontium oxide hydration resistance titanium-nickel alloy induction melting

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Research on virtual entity decision model for LVC tactical confrontation of army units

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1249-1267页

作者： GAO Ang GUO qisheng DONG Zhiming TANG Zaijiang ZHANG Ziwei feng Qiqi Military Exercise and Training Center Army Academy of Armored ForcesBeijing 100072China

According to the requirements of the live-virtual-constructive(LVC)tactical confrontation(TC)on the virtual entity(VE)decision model of graded combat capability,diversified actions,real-time decision-making,and generalization for the enemy,the confrontation process is modeled as a zero-sum stochastic game(ZSG).By introducing the theory of dynamic relative power potential field,the problem of reward sparsity in the model can be solved.By reward shaping,the problem of credit assignment between agents can be solved.Based on the idea of meta-learning,an extensible multi-agent deep reinforcement learning(EMADRL)framework and solving method is proposed to improve the effectiveness and efficiency of model solving.Experiments show that the model meets the requirements well and the algorithm learning efficiency is high.

关键词： live-virtual-constructive(LVC) army unit tactical confrontation(TC) intelligent decision model multi-agent deep reinforcement learning

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The urgent need to develop a new grassland map in China:based on the consistency and accuracy of ten land cover products

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Science China(Life Sciences) 2023年第2期66卷 385-405页

作者： Mengjing Hou Jing Ge Yangjing Xiu Baoping Meng Jie Liu qisheng feng Tiangang Liang State Key Laboratory of Grassland Agro-Ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of Agriculture and Rural AffairsEngineering Research Center of Grassland IndustryMinistry of EducationCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China Institute of Fragile Eco-Environment Nantong UniversityNantong 226007China

Grasslands are the most dominant terrestrial ecosystem in China, but few national grassland maps have been generated. The grassland resource map produced in the 1980s is widely used as background data, but it has not been updated for almost 40 years.Therefore, a reliable map depicting the current spatial distribution of grasslands across the country is urgently needed. In this study, we evaluated the grassland consistency and accuracy of ten land cover datasets(GLC2000, GlobCover, CCI-LC,MCD12Q1, CLUD, GlobeLand30, GLC-FCS30, CGLS-LC100, CLCD, and FROM-GLC) for 2000, 2010, and 2020 based on extensive fieldwork. We concluded that the area of these ten grassland products ranges from 107.80×10^(4)to 332.46×10^(4)km^(2), with CLCD and MCD12Q1 having the highest area consistency. The spatial and sample consistency is highest in the regions of eastcentral Inner Mongolia, the Qinghai-Tibet Plateau and northern Xinjiang, while the distribution of southern grasslands is scattered and differs considerably among the ten products. MCD12Q1 is significantly more accurate than the other nine products,with an overall accuracy(OA) reaching 77.51% and a kappa coefficient of 0.51;CLCD is slightly less accurate than MCD12Q1(OA=73.02%, kappa coefficient=0.45) and is more conducive to the fine monitoring and management of grassland because of its30-meter resolution. The highest accuracy of grassland was found in the Inner Mongolia-Ningxia region and Qinghai-Tibet Plateau, while the accuracy was worst in the southeastern region. In the future grassland mapping, cartographers should improve the accuracy of the grassland distribution in South China and regions where grassland is confused with forest, cropland and bare land. We specify the availability of valuable data in existing land cover datasets for China’s grasslands and call for researchers and the government to actively produce a new generation of grassland maps.

关键词： grassland land use and land cover MCD12Q1 CLCD consistency comparison accuracy assessment

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基于UPLC-Q-Orbitrap HRMS代谢组学和16S rRNA基因测序探讨骨疏丹补肾机制

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沈阳药科大学学报 2024年第6期41卷 675-685,698页

作者：佟琳冯啟圣张静陆晴石伟赵龙山熊志立沈阳药科大学药学院辽宁沈阳110016

目的整合代谢组学和肠道微生物组学的研究策略探讨骨疏丹(Gushudan, GSD)预防氢化可的松诱导的肾阳虚证(kidney-yang deficiency syndrome, KYDS)大鼠的补肾作用机制。方法分别采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UPLC... 详细信息

目的整合代谢组学和肠道微生物组学的研究策略探讨骨疏丹(Gushudan, GSD)预防氢化可的松诱导的肾阳虚证(kidney-yang deficiency syndrome, KYDS)大鼠的补肾作用机制。方法分别采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap HRMS)的非靶向代谢组学和16S rRNA基因测序分析的肠道微生物组学方法,分析正常对照组、肾阳虚证模型组、骨疏丹给药组和阳性对照组大鼠粪便代谢物谱与肠道菌群组成,采用Pearson相关分析探讨内源性差异代谢物与差异菌群之间的相关性。结果基于UPLC-Q-Orbitrap HRMS的代谢组学方法在正负离子模式下共发现骨疏丹参与调控肾阳虚症的22种差异代谢物,如色氨酸、鹅去氧胆酸、肌酐和油酸酰胺等,主要涉及氨基酸代谢、胆汁酸代谢、能量代谢和脂质代谢。基于16S rRNA测序分析发现骨疏丹在属水平显著上调普雷沃氏菌(Prevotellaceae)的相对丰度(P<0.05),显著下调颤杆菌(Oscillibacter)的相对丰度(P<0.05)。相关性分析结果表明甘胆酸和鹅去氧胆酸与在属水平显著改变的普雷沃氏菌(Prevotellaceae)显著正相关(P<0.05),而与考拉杆菌(Phascolarctobacterium)显著负相关(P<0.05)。二十二碳六烯酸与毛螺菌(Lachnospiraceae)显著负相关(P<0.05)。结论骨疏丹通过良性调节内源性代谢和肠道菌群结构发挥补肾作用,为中药通过肠-肾轴治疗疾病提供新的思路和方法。

关键词：肾阳虚证骨疏丹代谢组学肠道菌群 UPLC-Q-Orbitrap HRMS 16S rRNA基因测序

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食物对艾司奥美拉唑镁、泮托拉唑钠和雷贝拉唑钠的药动学影响

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中国医院药学杂志 2024年第4期44卷 404-407页

作者：姜雅琦田杰李梦瑶张婷冯婉妮甘方良刘启胜湖北科技学院附属第一医院/咸宁市中心医院临床药理机构办公室湖北咸宁437100 湖北科技学院医学部药学院湖北咸宁437100

目的:基于质子泵抑制剂(proton pump inhibitors,PPIs)类药物的生物等效性试验,探讨不同给药条件下药动学参数的变化规律,为临床合理用药提供依据。方法:217例中国健康志愿者在空腹或进食条件下单剂量口服PPIs类药物(艾司奥美拉唑镁肠... 详细信息

目的:基于质子泵抑制剂(proton pump inhibitors,PPIs)类药物的生物等效性试验,探讨不同给药条件下药动学参数的变化规律,为临床合理用药提供依据。方法:217例中国健康志愿者在空腹或进食条件下单剂量口服PPIs类药物(艾司奥美拉唑镁肠溶胶囊40 mg、泮托拉唑钠肠溶片40 mg或雷贝拉唑钠肠溶片10 mg),根据方案要求采集静脉血样,用超高效液相色谱-串联质谱(UPLC-MS/MS)法分别测定人血浆中PPIs类药物的浓度,Phoenix WinNonlin 8.2统计软件计算药动学参数。结果:餐后给药艾司奥美拉唑镁T_(max)显著增加,C_(max)和AUC降低;泮托拉唑钠T_(max)增加,AUC降低;雷贝拉唑钠T_(max)、C_(max)和AUC均增加。结论:食物延迟PPIs类药物的吸收,影响生物利用度,临床适宜空腹给药。

关键词：质子泵抑制剂艾司奥美拉唑镁泮托拉唑钠雷贝拉唑钠药动学

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2D-polyimide film sensitized monolayer MoS_(2) phototransistor enabled near-infrared photodetection

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Nano Research 2022年第9期15卷 8428-8434页

作者： Qingqing Luo Guangyuan feng Yaru Song Enbing Zhang Jiangyan Yuan Dejuan Fa qisheng Sun Shengbin Lei Wenping Hu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)-based heterostructures open the door to fabricate various promising hybrid photodetectors,while it is still a challenge to achieve excellent and stable near-infrared(NIR)photoresponse.Here,a MoS_(2)–2DPI(2D-polyimide(2DPI))heterojunction-based phototransistor(HPT)was fabricated.Near-infrared photodetection with excellent performance has been realized.This HPT exhibited a photoresponsivity of 390.5 A/W,a specific detectivity of 5.10×10^(12)Jones,a photogain 1.04×10^(5),and a photoresponse rise and decay time of 400 and 430 ms(λ=900 nm,P=16.2μW/cm^(2)),respectively.It also shows a broadband wavelength response from 405 to 1,020 nm.This superior performance could be attributed to the strong near-infrared absorption and the type-II(staggered)band alignment which ensures efficient charge transfer from 2DPI to MoS_(2).The face-to-face spatial configuration of MoS_(2)–2DPI heterostructures ensures efficient transfer of photoinduced carriers through the interface,electron and holes can be separated due to the large band offsets.This work presents a significant step for the manipulation of high-performance NIR photodetector of twodimensional covalent organic polymer-sensitized monolayer TMDCs.

关键词： MoS_(2) polyimide film heterojunction near-infrared phototransistor

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RR-1 cuticular protein TcCPR69 is required for growth and metamorphosis in Tribolium castaneum

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Insect Science 2022年第6期29卷 1612-1628页

作者： Jia Xie Guifang Peng Miao Wang qisheng Zhong Xiaowen Song Jingxiu Bi Jing Tang Fan feng Han Gao Bin Li Jiangsu Key Laboratory of Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjingChina Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests Ministry of EducationCollege of Plant Protection HainanUniversityHaikouChina

Cuticle is not only critical for protecting insects from noxious stimuli but is also involved in a variety of metabolic activities.Cuticular proteins(CPs)affect cuticle structure and mechanical properties during insect growth,reproduction,and environmental adaptation.Here,we describe the identification and characterization of a member of the RR-1 subfamily of CPs with an R&R consensus(CPR)in Tribolium castaneum(TcCPR69).Although it was previously reported to be highly expressed in the wings,we found that knocking down TcCPR69 by RNA interference(RNAi)did not cause obvious wing abnormalities but markedly disrupted the growth and metamorphosis of beetles with 100%cumulative mortality;additionally,the chitin content of the pharate adult was decreased and the new abdominal cuticle was significantly thinner before molting.TcCPR69 showed chitin-binding ability and the expression levels of key genes involved in chitin metabolism(trehalase[TcTRE],chitin synthase[TcCHSA and TcCHSB],and chitinase[TcCHT5 and TcCHT10])were also decreased by TcCPR69 knockdown.TcCPR69 gene expression peaked shortly after molting and was increased 2.61 fold at 12 h after 20-hydroxyecdysone(20E)injection.This was reversed by RNAi of the ecdysone-related genes ecdysone receptor(TcECR)and fushi tarazu transcription factor 1(TcFTZ-F1).These results indicate that TcCPR69 is positively regulated by 20E signaling to contribute to cuticle formation and maintain chitin accumulation during the growth and metamorphosis of beetles.

关键词： chitin accumulation cuticle protein development 20-hydroxyecdysone molting RNA interference

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基于深度学习的栽培苜蓿害虫识别模型

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草业科学 2024年第6期41卷 1519-1532页

作者：张忠雪冯琦胜李仲贤李云昊王瑞泾张轩凡李彦忠梁天刚草种创新与草地农业生态系统全国重点实验室/兰州大学草地农业科技学院甘肃兰州730000 兰州大学图书馆甘肃兰州730000

苜蓿(Medicago sativa)是我国发展畜牧业的重要优质牧草之一,而病虫害是影响其生长和品质的主要原因,因此准确识别病虫害对其生长发育具有重要意义。YOLO(You Only Look Once)等单阶段目标检测算法通过端对端进行目标检测,RCNN(Region C... 详细信息

苜蓿(Medicago sativa)是我国发展畜牧业的重要优质牧草之一,而病虫害是影响其生长和品质的主要原因,因此准确识别病虫害对其生长发育具有重要意义。YOLO(You Only Look Once)等单阶段目标检测算法通过端对端进行目标检测,RCNN(Region Convolutional Neural Network)等双阶段目标检测算法生成候选区域进行特征提取。为有效识别苜蓿害虫,本文基于YOLOv5和Faster-RCNN两种算法对常见的6类苜蓿害虫进行特征识别,根据召回率(R)、精度(P)、平均精度(mAP)、F1值4种评价指标确定苜蓿害虫识别的最优算法和模型。其中R为样本中的正例被正确预测的比例,F1值为R和P的加权平均值。结果表明:YOLOv5算法识别苜蓿害虫的表现优于Faster-RCNN算法,YOLOv5算法的测试集和验证集精度均高于Faster-RCNN算法。研究结果为苜蓿害虫识别的算法选择提供了科学与理论支撑,对栽培苜蓿管理具有重要意义。

关键词：深度学习 YOLOv5算法 Faster-RCNN算法苜蓿害虫

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