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饲料中添加丁酸梭菌或丁酸钠对大口黑鲈生长性能、血清生化指标、肝脏免疫和抗氧化能力的影响

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动物营养学报 2024年第4期36卷 2572-2585页

作者：侯冬强李敏李培佳彭凯陈冰黄文曹俊明郭慧赵红霞广东海洋大学水产学院湛江524088 广东省农业科学院动物科学研究所农业农村部华南动物营养与饲料重点实验室广东省畜禽育种与营养研究重点实验室广州510640

本试验旨在研究饲料中添加丁酸梭菌(CB)或丁酸钠(SB)对大口黑鲈(Micropterus salmoides)幼鱼生长性能、血清生化指标、肝脏免疫、抗氧化能力以及低氧应激的影响。试验配制3种等氮(50%)和等脂(9%)的饲料,分别为基础饲料(Con)、基础饲料... 详细信息

本试验旨在研究饲料中添加丁酸梭菌(CB)或丁酸钠(SB)对大口黑鲈(Micropterus salmoides)幼鱼生长性能、血清生化指标、肝脏免疫、抗氧化能力以及低氧应激的影响。试验配制3种等氮(50%)和等脂(9%)的饲料,分别为基础饲料(Con)、基础饲料中添加10 mL/kg的CB的试验饲料、基础饲料中添加1.0 g/kg的SB的试验饲料。选取体重为(5.02±0.01)g的大口黑鲈360尾,随机分为3组,分别饲喂3种饲料,每组3个重复,每个重复40尾鱼,开展8周的养殖试验,随后进行低氧应激试验。结果显示:1)与Con组相比,CB组增重率(WGR)和蛋白质沉积率(PDR)显著提高(P<0.05),CB组饲料系数(FCR)显著降低(P<0.05)。与Con组相比,CB组肠体比(ISI)显著增加(P<0.05)。2)与Con组相比,SB组血清中碱性磷酸酶(AKP)活性和甘油三酯(TG)含量显著降低(P<0.05),CB组和SB组血清尿素氮含量显著降低(P<0.05),SB组血清葡萄糖(GLU)含量显著升高(P<0.05)。3)与Con组相比,饲料中添加CB和SB可显著提高肝脏总蛋白(TP)含量(P<0.05),CB组和SB组肝脏过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和溶菌酶(LZM)活性显著提高(P<0.05);SB组肝脏丙二醛(MDA)含量显著低于Con组(P<0.05)。4)与Con组相比,SB组肝脏中Toll样受体22(TLR22)基因相对表达量显著增加(P<0.05),CB组和SB组白细胞介素-1β(IL-1β)、白细胞介素-8(IL-8)和髓样分化因子88(MyD88)基因相对表达量显著降低(P<0.05),CB组胰岛素样生长因子-1(IGF-1)和生长激素(GH)基因相对表达量显著提高(P<0.05)。5)低氧应激3 h后,Con、CB和SB组累计死亡率分别为68.75%、31.25%和35.42%。与Con组相比,CB组和SB组累计死亡率显著降低(P<0.05)。综上所述,饲料中添加CB和SB提高大口黑鲈生长性能、肝脏抗氧化能力,抑制肝脏抗炎因子的表达,提高低氧应激下的存活率;与SB相比,添加CB对提高大口黑鲈生长性能、免疫和抗氧化效果更佳。

关键词：大口黑鲈丁酸梭菌丁酸钠生长性能免疫抗氧化

高碳水化合物饲料添加精氨酸对杂交鳢的生长性能、抗氧化酶活性、肝脏免疫反应及糖代谢相关基因的影响

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水产学报 2024年第8期48卷 171-183页

作者：李培佳陈冰李敏彭凯胡俊茹黄文曹俊明赵红霞广东省农业科学院动物科学研究所广东省畜禽育种与营养研究重点实验室广东省农业科学院水产协同创新中心广东海洋大学水产学院广州飞禧特生物科技有限公司

为研究高碳水化合物饲料添加精氨酸对杂交鳢幼鱼生长性能、体组成、血浆生化、抗氧化酶活性、葡萄糖代谢以及免疫相关基因的影响。实验选取初始体重(22.02±0.02) g的杂交鳢450尾，随机分为3个组，每组3个重复，每个重复50尾鱼，分别投... 详细信息

为研究高碳水化合物饲料添加精氨酸对杂交鳢幼鱼生长性能、体组成、血浆生化、抗氧化酶活性、葡萄糖代谢以及免疫相关基因的影响。实验选取初始体重(22.02±0.02) g的杂交鳢450尾，随机分为3个组，每组3个重复，每个重复50尾鱼，分别投喂碳水化合物水平为21.34%(低，LC组)、27.45%(高，HC组)和27.38%(添加Arg,Arg组)的3种实验饲料饲喂8周。结果显示，与低碳水化合物饲料(LC组)相比，高碳水化合物饲料(HC组)显著降低杂交鳢增重率(WGR)、特定生长率(SGR)和蛋白质沉积率(PDR)，饲料系数(FCR)提高，精氨酸组(Arg组)的添加显著降低了FCR，显著提高了WGR、SGR、PDR、全鱼粗蛋白和血浆蛋白含量。与LC组相比，HC组血浆和肝脏丙二醛(MDA)含量和肝脏肿瘤坏死因子-α (TNF-α)表达量显著升高，肠道总抗氧化能力(T-AOC)、过氧化物酶(POD)、谷胱甘肽过氧化物酶(GSH-Px)，以及肝脏POD、GSH-Px活性、肝脏磷酸烯醇丙酮酸羧激酶(PEPCK)、葡萄糖转运蛋白-2 (GLUT2)、转化生长因子(TGF-β)和热休克蛋白70 (HSP70)基因表达量显著下降。氧化应激和肝脏炎症提示，喂食高碳水化合物饲料的杂交鳢患有肝脏疾病。饲喂添加Arg的饲料可以通过减少MDA的含量和增强T-AOC、POD、GSH-Px和超氧化物歧化酶(SOD)活性来增强肝脏的抗氧化能力。与HC组饲料相比，饲喂添加Arg饲料的杂交鳢促炎因子白细胞介素-8 (IL-8)、白细胞介素-1β (IL-1β)和TNF-α的表达量显著降低，抗炎因子TGF-β、HSP70和热休克蛋白90 (HSP90)表达量显著升高，提示饲料补充Arg后肝脏炎症反应得到缓解。研究表明，Arg通过上调肝脏胰岛素相关基因蛋白激酶B (AKT)、胰岛素受体底物-1 (IRS-1)、磷脂酰肌醇-3激酶(PI3K)和葡萄糖代谢相关基因PEPCK、葡萄糖-6磷酸酶(G6P)和丙酮酸激酶(PK)的表达来促进胰岛素的产生和糖原分解，从而调节鱼类的肝糖代谢。综上，高碳水化合物饲料可诱发杂交鳢的氧化应激和炎症，而补充Arg可增强抗氧化活性，缓解炎症，促进葡萄糖代谢。

关键词：杂交鳢精氨酸生长性能血浆生化抗氧化免疫

SNR periodical variation of Chang'E-3 spacecraft orbiting the Moon

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Chinese Journal of Aeronautics 2016年第2期29卷 470-478页

作者： he qingbao liu qinghui li peijia kawaguchi noriyuki wu yajun zheng xin zhang juan xu zhijun Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

Chang＇E-3 spacecraft was orbiting the Moon from December 6 14, 2013, and very long baseline interferometry （VLBI） observations were performed to improve the accuracy of its orbit determination. In the process of recording VLBI raw data, 2 bits quantization was implemented. Interesting phenomenon was that signal-to-noise ratio （SNR） of each VLBI station experienced periodical change and had large variation on amplitude while in the Moon＇s orbit, whereas SNR kept in a stable level after Chang＇E-3 landed on the Moon. Influence of varying elevation angle on SNR was analyzed and compensation of 2 bits quantization harmonics to SNR calculation was investigated. Most importantly, telescope system noise temperature increase caused by the Moon was computed along the time of Chang＇E-3 orbiting the Moon, and well matched SNR changing trend in terms of correlation coefficients.

关键词： 2 bits quantization Elevation angle Moon radiation SNR periodical variationVLBI

饲料中添加丁酸梭菌或丁酸钠对大口黑鲈幼鱼肠道短链脂肪酸含量、消化酶活性与抗氧化指标以及肠道结构的影响

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动物营养学报 2024年第9期36卷 5883-5894页

作者：侯冬强胡俊茹陈冰彭凯李培佳黄文曹俊明赵红霞广东省农业科学院动物科学研究所广东省畜禽育种与营养研究重点实验室农业农村部华南动物营养与饲料重点实验室广东省农业科学院水产协同创新中心广州510640 广东海洋大学水产学院湛江524088 广东省农业科学院广州510640 广州飞禧特生物科技有限公司广州510640

本试验旨在研究饲料中添加丁酸梭菌(CB)或丁酸钠(SB)对大口黑鲈(Micropterus salmoides)幼鱼肠道短链脂肪酸含量、消化酶活性与抗氧化指标以及肠道结构的影响。试验配制3种等氮(50%)和等脂(9%)的饲料,分别为基础饲料(对照组)、基础饲料+... 详细信息

本试验旨在研究饲料中添加丁酸梭菌(CB)或丁酸钠(SB)对大口黑鲈(Micropterus salmoides)幼鱼肠道短链脂肪酸含量、消化酶活性与抗氧化指标以及肠道结构的影响。试验配制3种等氮(50%)和等脂(9%)的饲料,分别为基础饲料(对照组)、基础饲料+10 mL/kg CB(CB组)、基础饲料+1.0 g/kg SB(SB组)。试验挑选360尾大口黑鲈[(5.02±0.01)g],随机分为3组,分别饲喂3种饲料,每组3个重复,每个重复40尾鱼。试验期为56 d。结果显示:1)与对照组相比,CB组终末体重和特定生长率显著提高(P0.05)。2)与对照组相比,CB组肠道中乙酸含量显著升高(P<0.05),CB组和SB组肠道丙酸、异丁酸和异戊酸含量显著提高(P<0.05)。3)与对照组相比,饲料中添加CB或SB可显著提高肠道中淀粉酶、胰蛋白酶和脂肪酶活性(P<0.05),CB组肠道中碱性磷酸酶活性显著提高(P<0.05),SB组肠道中钠钾ATP酶活性显著提高(P<0.05)。4)CB组和SB组肠道中过氧化氢酶活性显著高于对照组(P<0.05)。与对照组相比,SB组肠道中丙二醛含量显著降低(P<0.05),CB组肠道中总抗氧化能力显著提高(P<0.05)。5)与对照组相比,CB组中肠绒毛宽度显著增加(P<0.05),减轻了肠道炎症反应。综上所述,饲料中添加CB显著提高了大口黑鲈幼鱼的生长性能,添加CB或SB增加了大口黑鲈肠道短链脂肪酸含量,显著提高了肠道消化酶活性与抗氧化指标以及改善肠道结构,与SB组相比,添加10 mL/kg的CB对提高大口黑鲈生长性能、肠道抗氧化指标以及增加肠道绒毛宽度效果更佳。

关键词：大口黑鲈丁酸梭菌丁酸钠消化酶抗氧化酶肠道结构

Effects of dietary sodium butyrate on growth,digestive enzymes,body composition and nutrient retention-related gene expression of juvenile yellow catfish (Pelteobagrus fulvidraco)

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Animal Nutrition 2021年第2期7卷 539-547页

作者： Hongxia Zhao Guoxia Wang Hairui Wang Wenyan Mo Yanhua Huang Junming Cao peijia li Institute of Animal Science Guangdong Academy of Agricultural SciencesGuangzhou 510640China Key Laboratory of Animal Nutrition and Feed Science in South China Ministry of Agriculture and Rural AffairsGuangzhou 510640China Guangdong Key Laboratory of Animal Breeding and Nutrition Guangzhou 510640China Guangdong Ocean University Zhanjiang 524088China

An 8-week feeding trial was conducted to evaluate the effects of sodium butyrate(SB)on growth,digestive enzymes,body composition and nutrient retention-related gene expression of juvenile yellow catfish(Pel-teobagrus fulvidraco).Five isonitmgenous and isolipidic diets(420 g/kg protein and 90 g/kg lipid)were formulated to contain 0(control),250,500,1,000 or 2,000 mg/kg *** groups of 40 fish(BW=1.26±0.01 g)per tank(300-L cylindrical fiberglass tanks)for each diet were fed to apparent satiation twice ***,hepatopancreas and intestine samples were obtained for digestive enzymes activities analyses.A real-time quantitative PCR analysis was performed to determine the relative expression of target of rapa-mycin(TOR)and lipoprotein lipase(LPL)in the hepatopancreas and *** fed the diets supplemented with SB at 500 and 1,000 mg/kg showed significantly higher specific growth rate and significantly lower feed conversion ratio compared to the control(Plipase,intestinal lipase,alkaline phosphatase and y-glutamyl trans-peptidase for fish fed 1,000 mg/kg SB compared to the control(Plipid content and hepatopancreas LPL mRNA expression in 2,000 mg/kg SB gmup were significantly higher than the control(P<0.05).Relative mRNA levels of intestinal LPL and hepatopancreas TOR were significantly higher in the 500 mg/kg SB group compared to those in other groups(P<0.05).The increased

关键词： Sodium butyrate Growth Digestion Absorption Target of rapamycin lipoprotein lipase

Orbit determination for Chang'E-2 lunar probe and evaluation of lunar gravity models

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 514-522页

作者： li peijia Hu XiaoGong Huang Yong Wang Guangli Jiang DongRong Zhang XiuZhong Cao JianFeng Xin Nan Chinese Acad Sci Shanghai Astron Observ Shanghai 200030 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China Beijing Aerosp Control & Command Ctr Beijing 100094 Peoples R China

The Unified S-Band （USB） ranging/Doppler system and the Very Long Baseline Interferometry （VLBI） system as the ground tracking system jointly supported the lunar orbit capture of both Chang＇E-2 （CE-2） and Chang＇E-1 （CE-1） missions. The tracking system is also responsible for providing precise orbits for scientific data processing. New VLBI equipment and data processing strategies have been proposed based on CE-1 experiences and implemented for CE-2. In this work the role VLBI tracking data played was reassessed through precision orbit determination （POD） experiments for CE-2. Significant improve- ment in terms of both VLBI delay and delay rate data accuracy was achieved with the noise level of X-band band-width syn- thesis delay data reaching 0.2-0.3 ns. Short-arc orbit determination experiments showed that the combination of only 15 min＇s range and VLBI data was able to improve the accuracy of 3 h＇s orbit using range data only by a 1-1.5 order of magnitude, confirming a similar conclusion for CE-1. Moreover, because of the accuracy improvement, VLBI data was able to contribute to CE-2＇s long-arc POD especially in the along-track and orbital normal directions. Orbital accuracy was assessed through the orbital overlapping analysis （2 h arc overlapping for 18 h POD arc）. Compared with about 100 m position error of CE-l＇s 200 kin x 200 km lunar orbit, for CE-2＇s 100 km x 100 km lunar orbit, the position errors were better than 31 and 6 m in the radial direction, and for CE-2＇s 15 km^100 km orbit, the position errors were better than 45 and 12 m in the radial direction. In addi- tion, in trying to analyze the Delta Differential One-Way Ranging （ADOR） experiments data we concluded that the accuracy of ADOR delay was dramatically improved with the noise level better than 0.1 ns and systematic errors better calibrated, and the Short-arc POD tests with ADOR data showed excellent results. Although unable to support the development of an independent lunar gravity model, the t

关键词： Chang'E-2 VLBI orbit determination lunar gravity field

基于SVM的海上风电场海底电缆故障诊断方法

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机电工程技术 2024年第9期53卷 17-21页

作者：黄海龙李树楠支光凝肖石李佩家朱嵘华中海石油(中国)有限公司北京100010 渤海石油航务建筑工程有限责任公司天津300452 浙江大学海洋学院浙江舟山316021 阳江海上风电实验室广东阳江529500

海上风电场海底环境复杂,长距离海缆常因环境因素或人为破坏发生故障。为解决海上风电场海缆故障难以监测、故障类型难以判断的问题,提出一种基于SVM (支持向量机)的海上风电场海底电缆故障诊断方法。通过MATLAB Simulink平台建立海底... 详细信息

海上风电场海底环境复杂,长距离海缆常因环境因素或人为破坏发生故障。为解决海上风电场海缆故障难以监测、故障类型难以判断的问题,提出一种基于SVM (支持向量机)的海上风电场海底电缆故障诊断方法。通过MATLAB Simulink平台建立海底电缆故障仿真系统进行海缆三相交流电路故障模拟,模拟中设置不同故障类型及故障位置组合,获取发生故障时海缆的首端和尾端的海缆电压、电流幅值及相位特征进行分析,并利用不同海缆故障类型对应的电压数据作为训练样本对SVM模型进行训练,建立具有不同核函数的SVM海缆故障类型判断依据进而开展故障诊断。仿真及计算结果表明,采用线性核函数的SVM模型对海缆的故障预测效果最佳,同时具有较高的计算效率,所提方法对不同类型的海缆故障都具有较高的识别精度,可为海上风电场海缆故障诊断提供参考。

关键词：海上风电海底电缆故障诊断 SVM算法

Characteristics and influencing factors of greenhouse gas emissions from reservoirs in the Yellow River Basin:A Meta-analysis

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Science China Earth Sciences 2024年第7期67卷 2210-2225页

作者： Shurui HUANG peijia ZHANG Wenxiu ZHENG Jiajia ZHANG Yang li Yuanjian WANG Enhui JIANG Shaoda liU Xinghui XIA State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 00875China Yellow River Institute of Hydraulic Research Yellow River Conservancy CommissionZhengzhou 450003China

Reservoir construction and operation profoundly alter the hydrological,hydrodynamic,and carbon and nitrogen cycling processes of ***,current research still lacks a systematic understanding of the characteristics of greenhouse gas(GHG)emissions from reservoirs in arid/semi-arid *** study integrates existing monitoring data to discuss the characteristics of GHG emissions from reservoirs in the Yellow River Basin and illustrate the controlling factors and underlying mechanism of these *** results indicate that while CO_(2) emission flux from reservoirs is lower than that from river channels,the emission fluxes of CH_(4) and N_(2)O are 1.9 times and 10 times those from rivers,respectively,indicating that the emission of GHG with stronger radiative effect is significantly enhanced in *** to the reservoirs in humid climates(e.g.,the Three Gorges Reservoir),reservoirs in the Yellow River Basin exhibit relatively lower emissions of CO_(2) and CH_4 due to lower organic matter concentrations,but significantly higher N_(2)O emissions due to higher nitrogen *** Carlo simulations for 237 reservoirs in the Yellow River Basin showed that total emission of the three GHGs is 3.05 Tg CO_(2)-eq yr^(-1),accounting for 0.39% of the total emission from global reservoirs and lower than the area percentage of the basin(0.53%).This study has important implications on revealing the GHG emission characteristics and control mechanisms of reservoirs in arid/semi-arid regions.

关键词： Yellow River Basin Reservoir Greenhouse gas Emission flux Water quality

High-performance wood-based thermoelectric sponges for thermal energy harvesting and smart buildings

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Nano Research 2024年第6期17卷 5349-5357页

作者： Ding Zhang Qi li Yanjie Fang peijia Bai lili liu Jiaqi Guo Guangfa Wang Yuetong Zhou Rujun Ma School of Materials Science and Engineering National Institute for Advanced MaterialsSmart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300350China

The development of renewable woods for power generation can help improve the energy efficiency of buildings,and promote the concept design and implementation of“smart buildings”.Here,with specific chemical treatment and hydrothermal synthesis,we demonstrated the practical value of natural wood for thermoelectric power generation in smart *** prepared wood-based thermoelectric sponges show high Seebeck coefficients of 320.5 and 436.6μV/K in the vertical and parallel directions of the longitudinal channel of *** 500 cycles of the compressive strain at 20%,the corresponding Seebeck coefficients increase up to 413.4 and 502.1μV/K,respectively,which is attributed to the improved contact and connection between tellurium thermoelectric *** Seebeck coefficients are much larger than those of most reported inorganic thermoelectric ***,the thermoelectric sponges maintain excellent thermoelectric and mechanical *** further modeled the application value of wood-based thermoelectric sponges in smart buildings for power *** high thermoelectric electricity can be obtained,such as in Beijing with over 1.5 million kWh every year,demonstrating the great potential in thermal energy harvest and energy supply.

关键词： wood thermoelectric effect thermal energy harvesting smart buildings energy supply