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Improvement, Comparison, and Application of Field Measurement Methods for Grassland Vegetation Fractional Coverage

Journal of Integrative Plant Biology 2005年第9期47卷 1074-1083页

作者： Xiao-Bing li yun-Hao CHEN hua YANG yun-Xia ZHANG College of Resources Sciences and Technology Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education Beijing Normal University Beijing 100875 China

As one of the important vegetation parameters, vegetation fractional coverage （VFC） is more difficult to measure accurately among a good many parameters of plant communities. The temperate typical steppe in the north of China was chosen for investigation in the present study and a digital camera was used to measure herb community coverage in the field, adopting methods of ocular estimation, gridding measurement, visual interpretation, supervised classification, and information extraction of color spatial transformation to calculate the VFC of images captured by the digital camera. In addition VFC calculated by various methods was analyzed and compared VFC, enabling us to propose an effective method for measuring VFC using a digital camera. The results of the present study indicate that：（i） as two common useful and effective methods of measuring VFC with a digital camera, not only does the error of estimated values of visual estimation and supervised classification vary considerably, but the degree of automatization is very low and depends, to a great extent, on the manipulator; （ii） although the method of visual interpretation may assure the precision of the calculated VFC and enable the precision of results obtained using other methods to be determined, as far as large quantities of data are concerned, this method has the disadvantages of wasting time and energy, and the applications of this method are limited; （iii） the precision and stability of VFC calculated using the grid and node method are superior to those of visual estimation and supervised classification and inferior to those of visual interpretation, but, as for visual interpretation and supervised classification, gridding measurements are difficult to apply in practice because they are not time efficient; and （iv） in terms of the precision of calculation of the VFC, an information-extracting model based on an intensity, hue, saturation （IHS） color space-multi-component series segmentation strategy is s

关键词： color space transformation digital camera field measurement grassland vegetationfractional coverage.

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Galerkin-based extended Kalman filter with application to CO2 removal system

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Journal of Central South University 2020年第6期27卷 1780-1789页

作者： LV Ming-bo li yun-hua GUO Rui School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

The carbon dioxide removal system is the most critical system for controlling CO2 mass concentration in long-term manned *** order to ensure the controlling CO2 mass concentration in the cabin within the allowable range,the state of CO2 removal system needs to be estimated in real *** this paper,the mathematical model is firstly established that describes the actual system conditions and then the Galerkin-based extended Kalman filter algorithm is proposed for the estimation of the state of *** method transforms partial differential equation to ordinary differential equation by using Galerkin approaching method,and then carries out the state estimation by using extended Kalman *** experiments were performed with the qualification of the actual manned space *** simulation results show that the proposed method can effectively estimate the system state while avoiding the problem of dimensional explosion,and has strong robustness regarding measurement ***,this method can establish a basis for system fault diagnosis and fault positioning.

关键词： carbon dioxide removal system Galerkin infinite nonlinear filter extend Kalman filter

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舔砖产品的成分及其在反刍动物生产中的应用

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饲料研究 2024年第15期47卷 161-165页

作者：智宇李康田婧石璐璐张佳李蕴华金海郭天龙内蒙古自治区农牧业科学院内蒙古呼和浩特010031

舔砖是将反刍动物日常所需的营养物质(矿物质元素、维生素等)经科学合理配方加工而成的一种块状饲料,具有提高机体抗氧化水平、免疫能力、干物质采食量、饲料消化率和繁殖性能等生物活性功能。目前,舔砖已经广泛应用于反刍动物生产中,... 详细信息

舔砖是将反刍动物日常所需的营养物质(矿物质元素、维生素等)经科学合理配方加工而成的一种块状饲料,具有提高机体抗氧化水平、免疫能力、干物质采食量、饲料消化率和繁殖性能等生物活性功能。目前,舔砖已经广泛应用于反刍动物生产中,以改善反刍动物机体的健康状况。文章综述了舔砖的种类成分、原料配方、加工工艺以及其对反刍动物生长性能、生产性能和抗氧化水平的影响,以期为舔砖产品在反刍动物生产中的应用提供参考。

关键词：舔砖产品反刍动物生产性能抗氧化

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岳阳市现代物流产业发展现状与对策

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岳阳职业技术学院学报 2024年第1期39卷 54-57页

作者：谢天福李华云朱丹丹岳阳市物流发展服务中心湖南岳阳414000 湖南省岳阳生态环境监测中心湖南岳阳414000

岳阳市作为湖南省唯一的临江口岸城市,发展物流产业区位优势明显。本文通过实地调研,分析湖南省岳阳市现代物流产业发展现状,发现存在基础设施网络不完善、企业综合竞争力不强、运输结构不优、信息化程度不高等问题。基于此,应加快物流... 详细信息

岳阳市作为湖南省唯一的临江口岸城市,发展物流产业区位优势明显。本文通过实地调研,分析湖南省岳阳市现代物流产业发展现状,发现存在基础设施网络不完善、企业综合竞争力不强、运输结构不优、信息化程度不高等问题。基于此,应加快物流基础设施建设,积极引进物流行业头部企业,加快大数据物流信息平台建设,强化产业发展要素保障,以有效促进岳阳市物流产业高质量发展。

关键词：现代物流业多式联动高质量发展

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Long-term outcome and prognostic factors of intrahepatic cholangiocarcinoma

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Chinese Medical Journal 2009年第19期122卷 2286-2291页

作者： li Shao-qiang liANG li-jian hua yun-peng PENG Bao-gang HE Qiang LU Ming-de CHEN Dong Department of Hepatobiliary Surgery the First Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510080 China

Background The management of intrahepatic cholangiocarcinoma （ICC） remains a challenge due to poor prognosis. The aim of this study was to summarize the surgical management experience in recent 10 years and to identify the influencing factors related to outcome of patients with ICC in a single hepatobiliary center. Methods From January 1995 to June 2005, 136 patients with ICC undergoing surgery were reviewed retrospectively. Survival rates of patients were calculated using the Kaplan-Meier method and compared by using the log-rank test. The prognostic factors were identified by the Cox regression model. Results Seventy-nine of 136 patients underwent resection, and 65 of 79 patients were curative （R0）. The surgical mortality was 2.2%. The 1-, 3- and 5-year survival rates of patients undergoing R0 resection were 72.1%, 35.6% and 20.1% respectively, which were significantly longer than those who underwent palliative resection and exploration, respectively （P 〈0.01）. At stage IV of the disease, 10 patients who underwent aggressive curative resection achieved a better median survival than those （n=12） without resection （14 months vs 3 months, P 〈0.001）. The independent prognostic factors of the whole group were TNM stage （OR, 2.013, P=0.008） and curative resection （OR, 2.957, P=0.003）. Higher TNM stage （OR, 1.894, P=0.004） and lymph node metastasis （OR, 4.248, P=0.005） linked to poor prognosis after R0 resection. For patients without lymph node metastasis, the median survival of those who underwent regional lymphadenectomy was comparable with those who did not （18 months vs 22 months, P=0.817）. Conclusions R0 resection is mandatory for ICC patient to achieve long-term survival. Aggressive resection benefits for selected patients with local advanced disease. Higher TNM stage and lymph node metastasis were poor prognostic factors for ICC patients after R0 resection.

关键词： cholangiocarcinoma intrahepatic prognosis

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Improving flight performance of UAVs by ice shape modulation

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Chinese Journal of Aeronautics 2024年第8期37卷 49-62页

作者： Jiajun ZHANG Xuecheng liU hua liANG like XIE Biao WEI Haohua ZONG yun WU Yinghong li National Key Lab of Aerospace Power System and Plasma Technology Air Force Engineering UniversityXi’an 710038China Institute of Aero-Engine School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China

Aircraft icing poses a great threat to flight *** response to the characteristics of high-power consumption,large volume,and heavy weight of traditional anti-/de-icing technologies,the concept of ice shape modulation is proposed,which is called ice tolerant ***,the flight performance of Unmanned Aerial Vehicle(UAV)was compared in three states:no ice,full ice,and modulated ice through flight *** was found that ice shape modulation has a significant improvement effect on the aerodynamic performance of aircraft under icing *** the three modulated ice shape conditions in this experiment,the lift coefficient of the UAV under different ice shape modulation conditions increased by 18%–33%,and the stalling angle was delayed by 3°-5°.Subsequently,the pressure distribution,streamlines in the flow field,and detached vortex distribution of the UAV model in these three states were obtained through numerical simulation,to study the mechanism of ice shape modulation on the aerodynamic performance of *** simulation found that the reason for the improvement of the wings effect after ice shape modulation is that the modulated area forms a leading-edge protrusion structure similar to a vortex *** structure prolongs the mixed flow region on the wings surface and reduces the trend of flow separation,which plays a role in increasing lift and reducing drag for UAVs under icing ***,a reverse reachable set that can be used for unexpected state recovery is used as the definition of flight safety boundaries,and an aircraft dynamics model is established to obtain flight safety boundaries for different *** has found that the flight safety boundary of the UAV in a no ice state is greater than that in a modulated ice state,and the safety boundary in a modulated ice state is greater than that in a full ice *** with the full ice state,the flight safety boundary after modulation has expanded by 27.0%.The sch

关键词： Ice shape modulation Aerodynamic performance Reachable set Flight safety UAV

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A Dynamic Covalent Bonding-based Nanoplatform for Intracellular Co-Delivery of Protein Drugs and Chemotherapeutics with Enhanced Anti-Cancer Effect

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Chinese Journal of Polymer Science 2024年第5期42卷 559-569,I0005页

作者： Sai-Nan liu Jia-Hui Meng li-yun Cui hua Chen lin-Qi Shi Ru-Jiang Ma Key Laboratory of Functional Polymer Materials of Ministry of Education Institute of Polymer ChemistryTianjin Key Laboratory of Functional Polymer MaterialsState Key Laboratory of Medicinal Chemical BiologyFrontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China

Efficient intracellular delivery of protein drugs is critical for protein *** combination of protein drugs with chemotherapeutics represents a promising strategy in enhancing anti-cancer ***,co-delivery systems for efficient delivery of these two kinds of drugs are still lacking because of their different ***,we show a well-designed delivery system based on dynamic covalent bond for efficient intracellular co-delivery of ribonuclease A(RNase A)and doxorubicin(DOX).Two polymers,PEG-b-P(Asp-co-AspDA)and PAE-b-P(Asp-co-AspPBA),and two 2-acetylphenylboronic acid(2-APBA)-functionalized drugs,2-APBA-RNase A and 2-APBA-DOX,self-assemble into mixed-shell nanoparticles(RNase A/DOX@MNPs)via dynamic phenylboronic acid(PBA)-catechol bond between PBA and dopamine(DA)*** PBA-catechol bond endows the nanoparticles with high stability and excellent stimulus-responsive drug release *** the slight acidic environment at tumor tissue,RNase A/DOX@MNPs are positively charged,promoting their *** cellular uptake into endosome,further protonation of PAE chains leads to the rupture of endosomes because of the proton sponge effect and the cleavage of PBA-catechol bond promotes the release of two *** cytoplasm,the high level of GSH removed the modification of 2-APBA on *** restored RNase A and DOX show a synergistic and enhanced antic-cancer *** system may be a promising platform for intracellular co-delivery of protein drugs and chemotherapeutics.

关键词： Drug co-delivery Combination therapy Dynamic covalent bond

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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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International Journal of Ophthalmology(English edition) 2024年第4期17卷 736-747页

作者： liang-Pin li li-yun Yuan De-Shen Mao Xia hua Xiao-Yong Yuan Clinical College of Ophthalmology Tianjin Medical UniversityTianjin 300020China Tianjin Key Laboratory of Ophthalmology and Visual Science Tianjin Eye InstituteTianjin Eye HospitalTianjin 300020China School of Medicine Nankai UniversityTianjin 300071China Anhui Medical University Hefei 230032Anhui ProvinceChina Tianjin Aier Eye Hospital Tianjin UniversityTianjin 300190China

AIM:To analysis of research hotspots and trends on the application of premium intraocular lens(PIOLs)in the past 2 ***:The literature search was performed on the Web of Science and included PIOLs studies published between January 2000 and December *** retrieved literature was collated and analyzed by R-tool’s Bibliometrix package,CitNetExplorer,CiteSpace and other ***:A total of 1801 articles about PIOLs were obtained,most of which were published in Spain and the United *** organization that published the most articles was the University of Valencia in ***ó JL,and Montés-Micó R,from Spain were the most influential authors in this *** 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 *** 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 ***: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.

关键词： premium intraocular lens bibliometric H-index cataract surgery global trends

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Second pregnancy of trisomy 21 in a mother with mosaicism

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Chinese Medical Journal 2007年第14期120卷 1295-1296页

作者： CUI Ying-xia HAO li-jun WANG yun-hua XIA Xin-yi SHI Yi-chao LU Hong-yong YAO Bing huaNG Yu-feng Department of Reproduction and Genetics Jinling Hospital Clinical School of Medical College Nanjing University Nanjing 210002 China

In the case of a previous offspring with trisomy 21, recurrence risk for Down syndrome is about 1%. It may be due to chance, but the possibility of germline mosaicism for trisomy 21 in one of the parents has important... 详细信息

关键词： trisomy 21 mosaicism microsatellite markers

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Precise determination of the pole position of the exotic Z_(c)(3900)

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 84-90页

作者： yun-hua Chen Meng-lin Du Feng-Kun Guo School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Peng huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

We perform a unified description of the experimental data of the π^(+)π^(-)and J/ψπ^(±)invariant mass spectra for e^(+)e^(-)→J/ψπ^(+)π^(-)and the D^(0)D^(*-)mass spectrum for e^(+)e^(-)→D^(0)D^(*-)π^(+)at e^(+)e^(-)center-of-mass energies 4.23 and 4.26 *** analysis takes into account open-charm meson loops that contain triangle singularities,the J/ψπ-DD^(*)coupled-channel interaction respecting unitarity,and the strong ππ-KK final state interaction using dispersion *** analysis leads to a precise determination of the Z_(c)(3900)pole with the pole mass and width(3880.7±1.7_(stat)±22.4_(syst))MeV and(35.9±1.4_(stat)±15.3_(syst))MeV,respectively,and hints at that the DD^(*)molecular and non-molecular components are of similar importance in the Z_(c)(3900)formation.

关键词： exotic hadrons dispersion relations final state interaction triangle singularity

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