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Relationship between Science Teaching Practices and Students’Achievement in Singapore,Chinese Taipei,and the US:An Analysis Using TIMSS 2011 Data

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Frontiers of Education in China 2014年第4期9卷 519-551页

作者： su gao Department of Teaching&Learning University of NevadaLas VegasNV 89154-3005USA

The assumption that inquiry-based instruction is more effective in influencing student science achievement than traditional didactic teaching has been the driving force of science education reform in recent decades and in many ***,the empirical relationship between these two kinds of science teaching and student science performance is not soundly established,which is worth a careful *** through the theoretical perspectives of inquiry-based instruction and culturally relevant pedagogy,using a two-level hierarchical linear modeling(HLM)approach and simultaneous multiple regression,this study examines the above relationship using the Trends in International Mathematics and Science Study(TIMSS)20118th grade dataset from Singapore,Chinese Taipei,and the *** study found that for the low-performing students,none of the inquiry-based teaching practice items measured had a significant relationship with the science achievements at any performance levels of students in any country/region except for the case of two inquiry-based teaching practice items that were positively related to Chinese Taipei students’*** didactic teaching practice items were associated with the Singapore students’science achievement,three of these practice items were found negatively related to Chinese Taipei students’science achievement,and one traditional didactic teaching practice was negatively related to the science achievement of ***,for medium-and high-performing students,none of these inquiry-based or traditional didactic science-teaching practices were found to be positive predictors of science performance in all three countries/***,in the case of Chinese Taipei,one didactic teaching practice item was negatively related with the medium level performing students’achievement and two didactic teaching practices were found to hinder high-performing students’science achievements.

关键词： inquiry-based teaching practice didactic teaching practice science achievement international comparison

Reliability Evaluation of All-User Terminals in LEO Satellite Communication Network Based on Modular Reduction

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China Communications 2022年第2期19卷 235-246页

作者： Yangyang Du Sifeng Liu Zhigeng Fang su gao College of Economics and Management Nanjing University of Aeronautics&AstronauticsNanjing 211106Jiangsu ProvinceChina Institute of Telecommunication Satellite China Academy of Space Technology(CAST) Beijing 100094China

LEO satellite communication network has a large number of satellites distributed in low orbits,which leads to multiple coverage of many areas on the *** is hard work to describe and evaluate the reliability of LEO satellite communication *** solve this problem,the reliability of all-user terminals in LEO satellite communication network is defined,and the corresponding reliability evaluation method is proposed in the *** to the large scale of the interstellar network,a modular reduction algorithm using the modular network instead of the original network for state decomposition is proposed in this *** study shows that the calculation time of the proposed method is equivalent to 6.28%of the original state space decomposition *** this basis,the reliability of LEO satellite communication network is further *** is found that the reliability of LEO satellite network was more sensitive to the reliability of Inter-Satellite link and the satisfaction of global coverage in the early stage,and it is more sensitive to the reliability of the satellite in the later *** satellite-ground link has a relatively constant impact on of LEO satellite network.

关键词： reliability evaluation LEO satellite communication network modular approach full probability formula all-user terminals

Secretive expression of Aspergillus fumigatus phytase in tobacco improves phosphorus nutrition in plant

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High Technology Letters 2007年第4期13卷 436-440页

作者：王严 gao Xiaorong su Qiao An Lijia Department of Bioscience and Biotechnology School of Environment and Life Dalian University of Technology Dalian 116024 P.R. China

To generate transgenic plants capable of utilizing exogenous phytate, an Aspersgillus fumigatus phytase gene （fphyA） was constitutively expressed in tobacco and recombinant enzyme was secreted from plant roots into the rhizosphere using the signal sequence from tobacco calreticulin. After 40 days of plant growth in hydroponic media, phytase activities in leaves, stems, roots and growth media of transgenic plants were 8.6-fold, 7.4-fold, 12.6-fold and 14.3-fold higher than those of wild-type plants. Signifi- cant improvements in plant growth and phosphorus （P） utilization were observed in the transgenic plants. When phytate was supplied as the sole P source, 45-day-old transgenic tobaccos accumulated 1.0-fold and 0.5-fold more shoot and root biomass than wild-type tobaccos, with a concomitant of l. 7-fold increase in total P concentration. These results indicate that secretive expression of the A. fumigatus phytase improves acquisition and use of P from phytate in plants.

关键词： Aspergillus fumigatus phosphorus phytate phytase gene tobacco

Automatic Determination of Water Hardness by Vector Colorimetry with Acid Chrome Blue K

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Journal of Analysis and Testing 2023年第2期7卷 157-162页

作者： su gao Ming-Liang Ye Rui Ma Ai-Rong Liu Hong-Wen gao College of Environmental Science and Engineering Tongji UniversityShanghai 200092China Zhejiang CONBA Pharmaceutical Co.Ltd Hangzhou 310052China

Based on the Mg^(2+)complexation with acid chrome blue K(ACBK)at pH 10.2,an automatic system was designed to determine total hardness of *** system consists of a vector colorimeter,a multi-channel sampling pump and both reagents A and *** kinds of reagent solutions were prepared and used in this system,i.e.,ammoniacal buffer and ACBK—disodium magnesium EDTA *** experimental results of the standard solutions containing 2 and 3 mg/L of total hardness showed that the relative standard deviations(RSDs)were 1.9%and 2.2%,respectively,and the limit of detection(LOD)was only 0.035 mg/*** detection of four natural water samples showed that the recoveries were between 85.0%and 108.6%,consistent with those obtained by ICP-AES method.

关键词： Total hardness Online automatic detection Acid chrome blue K Vector chromaticity measuring device

survivability model of LEO satellite constellation based on GERT with limited backup resources

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Journal of Systems Engineering and Electronics 2024年第4期35卷 976-986页

作者： NIE Yuanyuan FANG Zhigeng LIU Sifeng gao su College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China Institute of Telecommunication Satellite China Academy of Space TechnologyBeijing 100094China

survivability is used to evaluate the ability of the satellite to complete the mission after failure,while the duration of maintaining performance is often *** effective backup strategy can restore the constellation performance timely,and maintain good network communication performance in case of satellite *** the perspective of network utility,the low Earth orbit(LEO)satellite constellation survivable graphical eva-luation and review technology(GERT)network with backup satel-lites is constructed.A network utility transfer function algorithm based on moment generating function and Mason formula is proposed,the network survivability evaluation models of on-orbit backup strategy and ground backup strategy are *** survivable GERT model can deduce the expected mainte-nance time of LEO satellite constellation under different fault states and the network utility generated during the state mainte-nance *** case analysis shows that the proposed surviv-able GERT model can consider the satellite failure rate,backup satellite replacement rate,maneuver control replacement ability and life requirement,and effectively determine the optimal sur-vivable backup strategy for LEO satellite constellation with limi-ted resources according to the expected network utility.

关键词： survivability low Earth orbit(LEO)satellite constella-tion graphical evaluation and review technology(GERT) backup strategy

A marching cube algorithm based on edge growth

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Virtual Reality & Intelligent Hardware 2021年第4期3卷 336-349页

作者： Xin WANG su gao Monan WANG Zhenghua DUAN Key Laboratory of Medical Biomechanics and Materials of Heilongjiang Province Harbin University of Science and TechnologyHarbin 15000China Beijing Normal University Hospital Beijing 100875China

The marching cube algorithm is currently one of the most popular three-dimensional(3D)reconstruction surface rendering *** forms cube voxels based on an input image and then uses 15 basic topological configurations to extract isosurfaces from the *** algorithm processes each cube voxel in a traversal-based manner,but it does not consider the relationship between the isosurfaces in adjacent *** to ambiguity,the final reconstructed model may have *** this paper,we propose a marching cube algorithm based on edge *** algorithm first extracts seed triangles,grows these seed triangles,and then reconstructs the entire 3D *** to the position of the growth edge,we propose 17 topological configurations with *** reconstruction results showed that the algorithm can reconstruct the 3D model *** only the main contour of the 3D model is required,the algorithm performs *** addition,when there are multiple scattered parts in the data,the algorithm can extract only the 3D contours of the parts connected to the seed by setting the region selected based on the seed.

关键词： 3D reconstruction Marching cube Edge growth

PS-G-GERT Effectiveness Evaluation Model of Link-Based GEO Satellite Communication Constellation under Poor Information Background

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China Communications 2022年第12期19卷 176-196页

作者： Ruirui Shao Zhigeng Fang su gao Sifeng Liu Weiqing You College of Economics and Management Nanjing University of Aeronautics&AstronauticsNanjing 211106China Institute of Telecommunication Satellite China Academy of Space Technology(CAST) Beijing 100094China National Cryptography Administration of Jiangsu Province Nanjing 210013China

The effectiveness evaluation of GEO satellite communication constellation not only characterizes the communication capability of the constellation but also provides a basis for optimizing the constellation *** due to information poverty or the complexity of the system,the impact of uncertain information on the effectiveness evaluation needs to be considered to ensure the accuracy of the evaluation *** address this issue,this paper develops a model for evaluating the GEO satellite communication constellation’s effectiveness in the context of poor ***,it analyses the GEO satellite communication constellation plus system based on communication links with an in-depth analysis of the constellation ***,an equivalent transfer function algorithm based on the characteristic function and transfer probability is proposed with the help of graphical evaluation and review ***,by analyzing the communication link importance connotation,the algorithm formula of communication link effectiveness and its importance is derived,and the constellation effectiveness and variance are ***,the model constructed in this paper is used to evaluate the effectiveness of a GEO satellite communication constellation,further verifying the accuracy and validity of the *** comparative analysis,it is shown that the model can not only solving the effectiveness of the constellation but also analyzing the variation of its *** lays a theoretical foundation for the analysis and optimization of the GEO satellite communication constellation effectiveness.

关键词： poor information graphical evaluation and review technique(GERT) plus system(PS) effectiveness evaluation

Internal mammary artery steal syndrome secondary to a para-IMA after coronary artery bypass graft： a case report

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Journal of Geriatric Cardiology 2009年第4期6卷 241-243页

作者： Jie gao Pi-Xiong su Yan Liu Department of Cardiac surgery Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China

Introduction The use of the intemal mammary artery （IMA） in coronary artery bypass graft（CABG） for myocardial revascularization is gaining popularity in routine practice, especially when the target vessel is the left anterior descending artery （LAD）. Occasionally, IMA hypoperfusion occurs when there is inadequate flow through the IMA graft to the LAD artery due to the exist of lateral branches.

关键词：冠状动脉 IMA 搭桥综合征继发窃取乳流量不足

Sexual characteristics of male guppies Poecilia reticulata serve as effect biomarkers of estrogens

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Journal of Oceanology and Limnology 2018年第4期36卷 1392-1400页

作者： TIAN Hua LI Yun WANG Wei ZHAO Fei gao su RU Shaoguo College of Marine Life Sciences Ocean University of China Qingdao 266003China

Guppies( Poecilia reticulata) are considered a candidate model species for the identification and testing of endocrine-disrupting chemicals. Male guppies may be used to address the challenge of making potential linkages between alterations of biomarkers, both at the cellular and organ level, and adverse outcomes. In the present study, a predictive relationship between sex characteristics and reproductive output was observed in male guppies that underwent a long-term toxicity test with 0.5 μg/L 17 β-estradiol administered during the juvenile period. Radioimmunoassay and western blot analyses demonstrated that 17 β-estradiol exposure caused a significant increase in testicular 17 β-estradiol levels as well as the induction of exposure biomarkers, namely hepatic vitellogenin. Exposure to 17 β-estradiol also caused a significant decrease in testosterone levels, which consequently reduced the gonadosomatic index, sperm counts, and the coloration index. These changes of male sexual characteristics further translated into adverse influences on reproduction, as measured by a decrease in offspring production and survival rate. Our results suggest that the above-mentioned sexual characteristics of male guppies may be considered potential in vivo biomarkers of estrogen effects on reproduction.

关键词： effect biomarker endocrine-disrupting chemical 17β-estradiol Poecilia reticulata reproduction sexual characteristic