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日粮添加杜仲叶粉对断奶仔猪生长性能、血清抗氧化指标和免疫功能的影响

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中国饲料 2024年第4期 21-24页

作者：丁佳颖周文韬张露园嵊州市畜牧业发展中心浙江嵊州312400

文章旨在研究日粮添加杜仲叶粉对断奶仔猪生长性能、血清抗氧化指标和免疫功能的影响。试验选择体重相近[(6.71±0.15)kg]、体况良好的24日龄断奶仔猪320头,随机分为4组,每组8个重复,每重复10头。对照组饲喂基础日粮,试验组分别向基础... 详细信息

文章旨在研究日粮添加杜仲叶粉对断奶仔猪生长性能、血清抗氧化指标和免疫功能的影响。试验选择体重相近[(6.71±0.15)kg]、体况良好的24日龄断奶仔猪320头,随机分为4组,每组8个重复,每重复10头。对照组饲喂基础日粮,试验组分别向基础日粮中添加300、600和900 mg/kg的杜仲叶粉。试验共41 d(其中预饲期6 d,正试期35 d)。试验结果表明,随杜仲叶粉添加量的提高,断奶仔猪平均日增重和终末体重显著提高(P 0.05)。日粮添加杜仲叶粉对断奶仔猪肝脏指数、肾脏指数、脾脏指数和腹股沟淋巴结指数均无显著影响(P> 0.05)。日粮添加600和900 mg/kg杜仲叶粉可显著提高断奶仔猪血清免疫球蛋白IgA、IgM和IgG含量(P cu-Zn SOD活性(P cAT活性无显著影响(P> 0.05)。总之,本试验结果表明,日粮添加杜仲叶粉可以提高断奶仔猪生长性能,改善机体血清抗氧化指标和免疫功能,在本试验条件下,断奶仔猪日粮杜仲叶粉最适添加量为600 mg/kg。

关键词：杜仲叶粉断奶仔猪生长性能抗氧化指标免疫功能

制度变迁理论视角下档案治理制度的供给演进、变迁逻辑及实践指向

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档案管理 2024年第4期 32-36页

作者：李宗富丁怡帆陈茜月郑州大学信息管理学院郑州大学档案与校史馆

对档案治理制度变迁规律深入研究有助于推动治理制度创新,推进档案治理体系和治理能力现代化建设。制度变迁理论的内在张力能够较好满足档案治理制度变迁的阐释需求,基于制度变迁理论将中华人民共和国成立后我国档案治理制度划分为一元... 详细信息

对档案治理制度变迁规律深入研究有助于推动治理制度创新,推进档案治理体系和治理能力现代化建设。制度变迁理论的内在张力能够较好满足档案治理制度变迁的阐释需求,基于制度变迁理论将中华人民共和国成立后我国档案治理制度划分为一元管控阶段、多元管理阶段和协同治理阶段,并从变迁特征和变迁动力两个方面分析档案治理制度变迁的内在逻辑。在此基础上探寻档案治理制度完善的现实路径,即助推多元主体协作、凝聚制度变迁合力,突破“路径依赖”桎梏、探寻制度变迁契机,正确把握制度变迁方向、最终实现档案治理善治。

关键词：制度变迁理论档案治理治理制度制度变迁

表面烧蚀对等离子体的影响及其与电磁场相互作用

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物理学报 2024年第11期73卷 237-250页

作者：丁明松刘庆宗江涛傅杨奥骁李鹏梅杰空天飞行空气动力科学与技术全国重点实验室绵阳621000 中国空气动力研究与发展中心计算空气动力研究所绵阳621000

表面烧蚀显著影响高速流动中等离体子鞘分布及其与电磁场相互作用的特征.考虑高超声速飞行器表面烧蚀引射机制、烧蚀产物参与流场等离子体生成过程、含碱金属的混合电离气体导电机理和电磁动力学机制,通过耦合求解带电磁源项的三维热化... 详细信息

表面烧蚀显著影响高速流动中等离体子鞘分布及其与电磁场相互作用的特征.考虑高超声速飞行器表面烧蚀引射机制、烧蚀产物参与流场等离子体生成过程、含碱金属的混合电离气体导电机理和电磁动力学机制,通过耦合求解带电磁源项的三维热化学非平衡流动控制方程、电场泊松方程和磁矢量泊松方程,建立了含碱金属烧蚀的高速流动/等离子体/电磁场耦合计算方法,结合常见的碳碳材料和硅基酚醛树脂材料烧蚀热解过程,较为系统地开展了多种条件下表面烧蚀对高超等离子体鞘影响及其与电磁场相互作用的机制与规律研究.研究表明:烧蚀效应对流场等离子体分布的影响受烧蚀质量引射率和碱金属质量占比共同作用,当碱金属含量较高时,碱金属电离反应占主导,电子数密度可增大1—2个数量级;不同材料烧蚀对等离子体的影响存在差别,硅基酚醛树脂的烧蚀质量引射率较大,电离生成cO^(+),c^(+)的摩尔分数接近空气主要电离组分NO^(+),O_(2)^(+),其影响不容忽视;烧蚀材料中碱金属可以显著提升磁流体力学控制效果,随着碱金属占比增大,电磁场耦合作用效果增强,二者呈非线性关系;在速度较低时,纯空气本身的电离度低导致电磁场耦合作用效果弱,通过含碱金属烧蚀来提升电磁作用效果的效率更高.

关键词：电磁流动耦合烧蚀碱金属等离子体高超声速流动

基于常规MRI影像组学预测急性脑梗死出血性转化的价值

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放射学实践 2024年第7期39卷 859-865页

作者：丁俊陈基明邵颖丁治民昌杰皖南医学院第一附属医院(弋矶山医院)放射科安徽芜湖241001 皖南医学院医学信息学院安徽芜湖241002

目的:探讨基于常规MRI影像组学预测急性脑梗死出血性转化(HT)的价值。方法:回顾性分析我院2017年1月-2022年12月120例急性脑梗死(HT阳性60例,HT阴性60例)的完整资料。所有患者均接受头颅常规MRI扫描,并随机将患者以7:3的比例分为训练组(... 详细信息

目的:探讨基于常规MRI影像组学预测急性脑梗死出血性转化(HT)的价值。方法:回顾性分析我院2017年1月-2022年12月120例急性脑梗死(HT阳性60例,HT阴性60例)的完整资料。所有患者均接受头颅常规MRI扫描,并随机将患者以7:3的比例分为训练组(n=84)和验证组(n=36)。运用软件勾画病灶ROI及提取纹理特征,利用最小冗余最大相关(mRMR)及最小绝对值收敛和选择算子(LASSO)回归分析筛选特征,构建影像组学模型。绘制受试者操作特征(ROc)曲线、应用决策曲线分析(DcA)评估模型的预测能力、临床应用价值。结果:临床模型、常规MRI模型、联合序列影像组学模型、个性化模型1及个性化模型2在训练组和验证组中曲线下面积(AUc)值分别为0.72(0.61~0.83)和0.68(0.50~0.86)、0.93(0.86~0.98)和0.93(0.79~0.99)、0.97(0.94~1.00)和0.97(0.93~1.00)、0.96(0.92~1.00)和0.99(0.98~1.00)、0.98(0.95~1.00)和0.98(0.96~1.00)。DcA表明个性化模型2患者临床受益好于个性化模型1。结论:常规MRI模型、联合序列影像组学模型、个性化模型1、个性化模型2均优于临床模型的诊断效能,均具有很高预测急性脑梗死出血性转化的价值。个性化模型1、2诊断效能相当,但个性化模型2患者临床受益好于个性化模型1。

关键词：急性脑梗死影像组学出血性转化

Artificial Neural Network-based prediction of glacial debris flows in the ParlungZangbo Basin, southeastern Tibetan Plateau,china

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Journal of Mountain Sc.ence 2021年第1期18卷 51-67页

作者： TANG Wang ding Hai-tao c.en Ning-sheng MA Shang-chang LIU Li-hong WU Kang-lin TIAN Shu-feng c.engdu University of Information Technology Chengdu 610225China Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Accurate prediction on geological hazards can prevent disaster events in advance and greatly reduce property losses and life *** debris flows are the most serious hazards in southeastern Tibet in china due to their complexity in formation mechanism and the difficulty in *** collected from 102 glacier debris flow events from 31 gullies since 1970 and regional meteorological data from 1970 to 2019 in ParlungZangbo River Basin in southeastern Tibet were used for Artificial Neural Network(ANN)-based prediction of glacial debris *** formation mechanism of glacial debris flows in the ParlungZangbo Basin was systematically analyzed,and the calculations involving the meteorological data and disaster events were conducted by using the statistical methods and two layers fully connected neural *** occurrence probabilities and scales of glacial debris flows(small,medium,and large)were predicted,and promising results have been *** the proposed model calculations,a prediction accuracy of 78.33%was achieved for the scale of glacial debris flows in the study *** prediction accuracy for both large-and medium-scale debris flows are higher than that for small-scale debris *** debris flow scale and the probability of occurrence increase with increasing rainfall and *** addition,the K-fold cross-validation method was used to verify the reliability of the *** average accuracy of the model calculated under this method is about 93.3%,which validates the proposed *** have proved that the combination of ANN and disaster events can provide sound prediction on geological hazards under complex conditions.

关键词： Two layers neural networks Glacial debris flow Disaster events K-fold cross-validation Rainfall Temperature

Adjusted Empirical Likelihood Estimation of Distribution Function and Quantile with Nonignorable Missing Data

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Journal of Systems Sc.ence & complexity 2018年第3期31卷 820-840页

作者： ding Xianwen TANG Niansheng Key Laboratory of Statistical Modeling & Data Analysis of Yunnan Province Yunnan University Kunming 650500 China Department of Mathematics Jiangsu University of Technology Changzhou 213001 China

This paper considers the estimation problem of distribution functions and quantiles with nonignorable missing response data. Three approaches are developed to estimate distribution functions and quantiles, i.e., the Horvtiz-Thompson-type method, regression imputation method and augmented inverse probability weighted approach. The propensity score is specified by a semiparametric expo- nential tilting model. To estimate the tilting parameter in the propensity score, the authors propose an adjusted empirical likelihood method to deal with the over-identified system. Under some regular conditions, the authors investigate the asymptotic properties of the proposed three estimators for distri- bution functions and quantiles, and find that these estimators have the same asymptotic variance. The jackknife method is employed to consistently estimate the asymptotic variances. Simulation studies are conducted to investigate the finite sample performance of the proposed methodologies.

关键词： Adjusted empirical likelihood distribution estimation exponential tilting model nonig-norable missing data quantile.

Safety Analysis of Flow Parameters in a Rotor-stator cavity

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chinese Journal of Aeronautics 2012年第6期25卷 831-838页

作者： ZHANG Gong ding Shuiting Airworthiness Technologies Research center Beihang University Beijing 100191 China National Key Laboratory of Sc.ence and Technology on Aero-engine Aero-thermodynamics School of Jet Propulsion Bei hang University Beij ing 100191 China

In order to ensure the safety of engine life limited parts （ELLP） according to airworthiness regulations, a numerical approach integrating one-way fluid structure interaction （FSI） and probabilistic risk assessment （PRA） is developed, by which the variation of flow parameters in a rotor-stator cavity on the safety of gas turbine disks is investigated. The results indicate that the flow parameters affect the probability of fracture of a gas turbine disk since they can change the distribution of stress and temperature of the disk. The failure probability of the disk rises with increasing rotation Reynolds number and chebyshev number, but descends with increasing inlet Reynolds number. In addition, a sampling based sensitivity analysis with finite difference method is conducted to determine the sensitivities of the safety with respect to the flow parameters. The sensitivity estimates show that the rotation Reynolds number is the dominant variable in safety analysis of a rotor-stator cavity among the flow parameters.

关键词： airworthiness aircraft engines engine life limited parts safety analysis rotor-stator cavity risk assessment

A qualitative and quantitative study of color emotion using valence-arousal

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Frontiers of computer Sc.ence 2012年第4期6卷 469-476页

作者： Shangfei WANG Rui ding Key Lab of computing and communicating Software of Anhui Province School of Computer Science and TechnologyUniversity of Science and Technology of ChinaHefei 230027China

This paper describes qualitative and quantita- tive analysis of color emotion dimension expression using a standard device-independent colorimetric system. To collect color emotion data, 20 subjects are required to report their emotion responses, using a valence-arousal emotion model, to 52 color samples that are chosen from cIELAB Lch color spaces. Qualitative analysis, including analysis of variance （ANOVA）, Pearson＇s correlation and Spearman＇s rank cor- relation, shows that significant differences exist between re- sponses to achromatic and chromatic stimuli, but there are no significant differences between chromatic samples. There is a positive linear relationship between lightness/chroma and valence-arousal dimensions. Subsequently, several clas- sic predictors are used to quantitatively predict emotion in- duced by color attributes. Furthermore, several explicit color emotion models are developed by using multiple linear re- gression with stepwise and pace regression. Experimental results show that chroma and lightness have stronger effects on emotions than hue, which is consistent with our qualitative results and other psychological studies. Arousal has greater predictive value than valence.

关键词： color emotion valence and arousal qualitative quantitative

加速溶剂萃取-离子色谱-串联质谱法测定种植土壤中5种强极性农药的残留量

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理化检验（化学分册） 2024年第8期60卷 827-831页

作者：李海侠李丽萍丁可山东省临沂生态环境监测中心临沂276000

考虑到采用现有方法检测草铵膦、增甘膦、脱落酸、灭草松和氨甲基膦酸时存在需要衍生化处理、色谱保留时间短等问题,进行了题示研究。取种植土壤样品,除杂、风干、过筛后,分取10 g,加入硅藻土20 g和体积比2∶1的甲醇-丙酮混合溶液25 mL... 详细信息

考虑到采用现有方法检测草铵膦、增甘膦、脱落酸、灭草松和氨甲基膦酸时存在需要衍生化处理、色谱保留时间短等问题,进行了题示研究。取种植土壤样品,除杂、风干、过筛后,分取10 g,加入硅藻土20 g和体积比2∶1的甲醇-丙酮混合溶液25 mL进行加速溶剂萃取。提取液过0.22μm聚醚砜滤膜,弃去初滤液,取续滤液上离子色谱-串联质谱仪检测。在色谱分析中,在Dionex IonPac AS17色谱柱上以0.1 mol·L^(-1)氢氧化钠溶液淋洗分离上述5种农药;在质谱分析中,以电喷雾离子源负离子模式电离,多反应监测(MRM)模式采集数据,外标法定量。结果显示,5种农药的质量浓度在0.001~5.0 mg·L^(-1)内和峰面积呈线性关系,检出限(3S/N)分别为0.012,0.009,0.007,0.013,0.005 ng·L^(-1);3个加标浓度水平下5种农药的回收率为84.4%~103%,测定值的相对标准偏差(n=5)为1.5%~3.7%。

关键词：加速溶剂萃取离子色谱-串联质谱法种植土壤强极性农药