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Effects of Neutral Detergent Soluble Fiber and Sucrose Supplementation on Ruminal Fermentation, Microbial Synthesis, and Populations of Ruminal Cellulolytic Bacteria Using the Rumen Simulation Technique (RUSITEC)

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Journal of Integrative Agriculture 2013年第8期12卷 1471-1480页

作者： zhao xiang-hui LIU Chan-juan LI Chao-yun YAO Jun-hu College of Animal Science and Technology Northwest A&F University

We evaluated the effects of neutral detergent soluble fiber （NDSF） and sucrose supplementation on ruminal fermentation, microbial synthesis, and populations of ruminal cellulolytic bacteria using the rumen simulation technique （RUSITEC）. The experiment had a 2x2 factorial design with two dosages of sucrose, low （ca. 0.26 g d-1, low-sucrose） and high （ca. 1.01 g d-1, high-sucrose）, and two dosages of supplied NDSF, low （1.95 g d-1, Iow-NDSF） and high （2.70 g d-1, high-NDSF）. Interactions between NDSF and sucrose were detected for xylanase activity from solid fraction and apparent disappearance of neutral detergent fiber （NDF） and hemicellulose, with the lowest values observed for high-NDSF and high-sucrose treatment. Supplemental NDSF appeared to increase the molar proportion of acetate and reduce that of butyrate; however, the effects of supplemental sucrose on VFA profiles depended upon NDSF amount. There was a NDSFxsucrose interaction for the production of methane. High-NDSF fermenters had lower ammonia-N production, greater daily N flow of solid- associated microbial pellets and total microorganisms, and greater microbial synthesis efficiency compared with low- NDSF fermenters. Supplementation with NDSF resulted in an increase in 16S rDNA copies of Ruminococcusflavefaciens and a reduction in copies of Ruminococcus albus. Supplementation with sucrose tended to increase the 16S rDNA copies ofR. albus from liquid fraction, but did not affect daily total microbial N flow and cellulolytic bacterium populations from solid fraction. These data indicate that the effects of the interaction between NDSF and sugars on ruminal fermentation and fiber digestion should be taken into account in diet formulation. Ruminal fermentation and metabolism of sugars warrant further investigation.

关键词： neutral detergent soluble fiber sucrose ruminal fermentation Rusitec

Construction of HIV-1 Virus-like Particle Vaccine

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Chemical Research in Chinese Universities 2008年第5期24卷 579-583页

作者： zhao Dong-hai ZHANG Xi-zhen YU xiang-hui KONG Wei College of Life Science Jilin University Changchun 130021 P. R. China Jilin Medical College Jinlin 132013 P. R. China

The virus-like particle（VLPs） vaccine is an ideal HIV-1 vaccine, which can simultaneously induce a neutralizing antibody reaction and cell-mediated immunity effectively. In this study, two kinds of plasmids have been used, one can express the HIV-1 main structure proteins, Gagpol and Env, and the other contains an antibiotic gene. The two kinds of plasmids have been cotransfected into 293 cells. A stable cell line that can express Gagpol and Env proteins efficiently and lastingly has been screened. It has been confirmed that Gagpol and Env proteins in the cell culture supernatant can be self-assembled into virus-like particles. The authors have detected the secretion of VLPs in the cell medium, defined the peak of the secretion, and followed and monitored the stability of expression.

关键词： HIV-1 Cotransfection Stable cell line Virus-like particles Vaccine

新型上胸椎椎弓根钉内固定系统的设计及其生物力学分析

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中国骨与关节损伤杂志 2017年第9期32卷 905-908页

作者：陈雍君华强段少银林永祥赵慧毅厦门大学附属中山医院脊柱外科福建厦门361004 厦门大学附属中山医院影像科福建厦门361004

目的测试新型上胸椎椎弓根钉内固定系统的生物力学性能。方法采用国际通用标准ASTM F543-2013及ASTM F1717-2013测试新型上胸椎椎弓根钉内固定系统的生物力学性能,进行单轴钉置入及拔出试验,万向钉压缩试验。并与常用颈胸椎椎弓根钉棒系... 详细信息

目的测试新型上胸椎椎弓根钉内固定系统的生物力学性能。方法采用国际通用标准ASTM F543-2013及ASTM F1717-2013测试新型上胸椎椎弓根钉内固定系统的生物力学性能,进行单轴钉置入及拔出试验,万向钉压缩试验。并与常用颈胸椎椎弓根钉棒系统(常用组)及强生椎弓根钉棒系统(强生组)进行比较。结果试验组置入力矩低于常用组,拔出力小于常用组,差异有统计学意义(P0.05)。试验组动态试验加载力最大值81 N为强生组的屈服力,反复加载后未损坏,故动态测试结果优于强生组。常用组动态试验加载力最大值110.9 N为试验组的屈服力,试验组与常用组反复加载后均未损坏,故动态试验结果接近。结论若上胸椎不稳但胸廓完整,新型上胸椎椎弓根钉内固定系统的生物力学性能可以满足临床的需要,提供即刻稳定性。

关键词：上胸椎新型椎弓根钉胸廓内固定生物力学

Elastoplastic Properties of Solid Oxide Fuel Cell Before and After Reduction

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Acta Metallurgica Sinica(English Letters) 2013年第2期26卷 137-142页

作者： xiang zhao Fenghui WANG Department of Engineering Mechanics Northwestern Polytechnical University

Oliver Pharr method may overestimate the hardness because of the effect of pile up. In this paper, the mechanical properties of oxide fuel cell, such as hardness and elastic modulus, are determined by a work of indentation, then a reverse analysis algorithms is followed to analyze the yield strength. From the nanoindentation tests carried out for the half-cell structure of solid oxide fuel cells （SOFCs）, the typical mechanical properties are derived by the work of indentation and the reverse analysis algorithms. Due to the differences of Young＇s modulus and the mismatch of thermal expansion coefficients in the half-cell structure （NiO-YSZ/YSZ）, the residual stress, which has effects on the fuel cell＇s performance, is aroused during sintering. Numerical results show that the load-displacement curve is agreement with the experimental curve if the residual stress was considered.

关键词： Solid oxide fuel cell Residual stress Nanoindentation Yield strength Reduction

An integrative mathematical model of microwave ion thruster for mHz-frequency thrust noise analysis

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Chinese Journal of Aeronautics 2024年第4期37卷 121-136页

作者： xiang NIU hui LIU Daren YU Plasma Propulsion Laboratory Harbin Institute of TechnologyHarbin 150001China

Many high-precision space missions need thrusters to produce thrust with low noise to compensate for disturbances and ensure satellite platform stability. Microwave ion thruster is characterized with a wide thrust range and potential for these missions. A cost-effective and accurate mathematical model is crucial for mHz-frequency thrust noise analysis and feedback controller design. The Particle-In-Cell(PIC) and global models are two common simulation tools. The PIC model is characterized with high accuracy but huge computation cost, which is difficult to analyze long-time performance characteristics. Now, the global model is only used for the discharge chamber with low accuracy and cannot reflect ion extraction properties. In this paper, an integrative mathematical model is built for a 1-cm microwave ion thruster and can reflect ion beamlet divergence and impingement on the Accelerator Grid(AG). Simulation results show good agreement with experiments at 0.06 sccm. However, the model demonstrates worse consistency with experiments when the flux increases to 0.1 sccm, which may be because the influence of neutral gas on the Electron Cyclotron Resonance(ECR) is not considered in the model. A long-time(1000 s) simulation is conducted with this model under 35 μN. It takes 3 hrs, and the thrust noise reaches 1 μN/Hz^(0.5) at 1 mHz.

关键词： Electric propulsion Microwave ion thruster Integrative model Sheath property Ion beamlet divergence Thrust noise Plasma

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing Guo Kai-xiang Di Lie-hui Zhang Yu-Long zhao hui-Ying Tang Rui-Han Zhang Ye Tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

Characterization of a Novel Chlorophyll-Deficient Mutant Mt6172 in Wheat

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Journal of Integrative Agriculture 2012年第6期11卷 888-897页

作者： GUO hui-jun zhao Hong-bing zhao Lin-shu GU Jia-yu zhao Shi-rong LI Jun-hui LIU Qing-chang LIU Lu-xiang Key Laboratory of Crop Genomics and Genetic Improvement Ministry of Agriculture/Beo'ing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100193 P.R.China National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

Identification of new chlorophyll-deficient mutants will provide materials for studying signaling components and pathways between plastid and nucleus. A novel chlorophyll-deficient mutant, named Mt6172, was obtained by spaceflight environment induction. Genetic analysis showed that its inheritance was controlled by nuclear and cytoplamic genes. Leaf color of its self-fertilized progenies was albino, narrow-white striped, or green. Only a few cells with abnormal chloroplasts were observed in albino plants and white section of narrow-white striped plants. These chloroplasts had obvious flaws in inner structure, and granum lamellae was extremely disordered. The narrow-white striped plants were characterized with green- and-narrow-white striped leaves, and the width of stripes between different plants was even, their plant height, number of productive tillers, and 1 000-grain weight were lower than those of the wild type. The narrow-white striped plants and the wild type had significant difference in the value of potential activity of photosystem II at all tested stages. At elongation stage, which was impacted the most seriously, effective quantum yield significantly decreased, whereas the energy for photoprotection and photodamage significantly increased. changes of electron transport rate, photochemical dissipation, Under different photosynthetic active radiation conditions, and effective quantum yield were different, electron transport rate was more impacted than other parameters. Therefore, the leaf morphology and inheritance of mutant Mt6172 was different from the other reported mutants in wheat, and it was a novel mutant of chloroDhvll deficiency.

关键词： Triticum aestivum L. space mutagenesis chlorophyll-deficient mutant agronomic traits chloroplastultrastructure

城区复杂条件下V形墩钢-混组合连续梁桥临时工程专项设计研究

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科学技术创新 2025年第2期 142-145页

作者：赵娥黄辉中交二航局第二工程有限公司重庆

本研究以双桥路道路工程施工为平台,开展城区复杂条件下V形墩钢-混组合连续梁桥支架体系研究。结合项目地形、地质特点及受限空间等多方面工况,利用三维建模及结构计算等手段综合考虑设计一套安全风险可控、经济价值高的临时工程体系,同... 详细信息

本研究以双桥路道路工程施工为平台,开展城区复杂条件下V形墩钢-混组合连续梁桥支架体系研究。结合项目地形、地质特点及受限空间等多方面工况,利用三维建模及结构计算等手段综合考虑设计一套安全风险可控、经济价值高的临时工程体系,同时,结合施工工序,将下部结构V形墩、钢箱梁顶推、上部结构混凝土箱梁等主要结构的支架统筹考虑,周转利用,节约施工工期,降低施工成本。

关键词： V形墩一体化支架体系受限空间钢箱梁拱圈拱架地质条件

Robust Regression Analysis for Clustered Interval-Censored Failure Time Data

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Journal of Systems Science & Complexity 2021年第3期34卷 1156-1174页

作者： LUO Lin zhao hui School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China School of Statistics and Mathematics Zhongnan Univer'sity of Economics and LawWuhan 430064China

Clustered interval-censored failure time data often occur in a wide variety of research and application fields such as cancer and AIDS studies. For such data, the failure times of interest are interval-censored and may be correlated for subjects coming from the same cluster. This paper presents a robust semiparametric transformation mixed effect models to analyze such data and use a U-statistic based on rank correlation to estimate the unknown parameters. The large sample properties of the estimator are also established. In addition, the authors illustrate the performance of the proposed estimate with extensive simulations and two real data examples.

关键词： Clustered data interval-censoring random effects rank estimation semiparametric transformation models