鸭IFIT5基因(544G>A)多态性与部分免疫指标的关联分析

探索IFIT5基因作为抗性性状的候选标记的可能性,为家禽抗病育种提供一些参考依据。以樱桃谷北京鸭、苏牧麻鸭(樱桃谷鸭×金定鸭)、金定鸭、白羽番鸭为试验材料,利用DNA直接测序技术扫描IFIT5基因单核苷酸多态性(SNP),并分析其与部分免疫指标的关联性。结果表明:仅在IFIT5基因外显子2上检测到一个错义突变(G544A),产生2种等位基因,2种基因型(GG、GA),未发现有AA基因型。经χ2检验,4个鸭群体只有金定鸭和苏牧麻鸭处于Hardy-Weinberg平衡状态。关联分析结果显示:樱桃谷鸭体内H5含量GG型显著高于GA型(P0.05),而Ig M含量GG型显著低于GA型(P0.05),其余免疫指标均无显著差异(P0.05);苏牧麻鸭体内H5含量GG型极显著高于GA型(P0.01),其余免疫指标均无显著差异(P0.05);金定鸭不同基因型各免疫指标均无显著差异(P0.05)。白羽番鸭在+544位点均为GG纯合基因型。由此可以看出,IFIT5(544GA)可作为樱桃谷鸭体内H5含量的候选分子标记。     

Estimation of the standardized ileal digestible lysine requirement for primiparous pregnant sows

This experiment was conducted to determine the optimal standardized ileal digestible lysine (SID Lys) level in diets fed to primiparous sows during gestation. A total of 150 (Landrace × Large White) crossbred gilts (weighing 149.9 ± 3.1 kg) were fed gestation diets (12.55 MJ of ME/kg) containing SID Lys levels of 0.43, 0.52, 0.60, 0.70 or 0.80% respectively. Gilts were fed 2.0 kg/day from day 1 to 80 and 3.0 kg/day from day 80 to 110 of gestation respectively. Gilts were allocated to treatments based on their body weight on the day of breeding. Weight gain from day 80 to 110 increased with increasing dietary SID Lys levels (p = 0.044). Fitted broken‐line (p = 0.031) and quadratic plot (p = 0.047) analysis of body weight gain indicated that the optimal SID Lys level for primiparous sows was 0.70 and 0.69% respectively. During gestation, neither backfat thickness nor loin eye area was affected by dietary SID Lys level. Increasing dietary Lys had no effect on the litter size at birth or pigs born alive per litter. Litter weight at birth was not affected by dietary SID Lys level. The litter weight variation at birth quadratically decreased with increasing dietary SID Lys (p = 0.021) and was minimized at 0.70% dietary SID Lys. Gilts fed the 0.70% SID Lys diet had the highest dry matter (p = 0.031) and protein (p = 0.044) content in colostrum. On day 110 of gestation, gilts fed the 0.70% SID Lys diet tended to have the highest serum prolactin (p = 0.085) and serum insulin (p = 0.074) levels. The data demonstrate that the optimal dietary SID Lys was 0.70% for pregnant gilts, which is similar to the recommendation of 0.69% that was estimated by the NRC (2012).     

珍稀濒危植物膝柄木种子催芽研究

以采自越南广宁省海河县的膝柄木种子为试材,研究了不同药剂和浓度对种子发芽率和芽苗主根生长的影响。结果表明:与水浸相比,艾比蒂生根剂1号和双吉尔氨基酸肥料6号0.5~15.0mg/L浸种1h,对膝柄木种子发芽均没有促进作用,可见水浸即可有效促进膝柄木种子发芽;艾比蒂生根剂1号0.5mg/L和双吉尔氨基酸肥料6号0.5~10.0mg/L对膝柄木芽苗主根生长有很好的促进作用。     

液压油液数字建模与仿真

因液压油液的温度、压力及油中已溶解或未溶解的空气量等因素变化时,油液的特性会发生非线性行为变化,从而影响液压系统的性能,为此对液压油的综合特性进行了研究。推导出溶解了空气的液压油液密度及油中空气含量随油液压力、温度变化的函数关系;应用Matlab软件编制的仿真程序,对液压油的非线性特性进行了大量仿真计算,并讨论了影响液压油密度、体积弹性模量的因素。     

三氯蔗糖在食品加工中的应用及测定方法的研究概况

介绍了三氯蔗糖的特性。阐述了三氯蔗糖在食品加工中的应用及测定方法的研究概况。     

牛Myostatin基因单核苷酸多态性分析

Myostatin基因即肌肉生长抑制素，是一种肌肉生长的负调控因子。应运PCR-SSCP和测序的方法对中国秦川牛、南阳牛以及国外引入品种皮埃蒙特牛双肌基因的第三外显子进行了多态性分析。结果表明：第三外显子938处G→A的单核苷酸的突变造成了南阳牛、皮埃蒙特牛第三外显子扩增片段多态性,秦川牛则不然。     

Pd Pattern Recognition Based on Linear Discriminant Analysis in GIS

According to the character of PD in GIS, the authors design four kinds of GIS defection models. The GIS gray intensity images are constructed based on mass specimens gathered by the ultra - high frequency and high speeds systems, Aiming at the PD characteristics and its defections, A PCA-FDA method is put forward based on PD images. The principal component analysis is employed to condense the dimension of PD images, then the optimal sets of statistically uncorrelated discriminant vectors are extracted, and the minimum distance classifier is constructed as classifier. The identified results show that this method can effectively elevated the discrimination of the four kinds of defects in GIS PD.     

Digital Beamforming for Unified Spread Spectrum TT&C System

In TT&C system,unified spread spectrum framework and adaptive antenna digital beamforming technologies are used to track, telemetry and command objects. Constant modulus array (CMA) and adaptive signal canceller estimate the direction of arrival (DOA) of every signal and use the optimum weighted vector to form the beams. The phase weighted vectors estimated from DOA improve the processing gain as well as being utilized in the transmitting of tele command signal to form the beam of specified object. Its processing performance is researched and simulated in this paper.     

Application and Advancement of Reinforced Earth Technique

In this paper, the application of reinforced earth technique, principle and calculation method, new reinforced materials developed and produced are introduced. A few of key technical problems in reinforced earth application is discussed, such as reinforced earth behavior, calculation method, durability of reinforced material, amendment and complement of the current standards. Then, the reinforced earth technique development and advancement were introduced.     

Real-time Vehicle Scheduling

The traditional scheduling for vehicle is option in the fixed network. But it can't satisfy the real time environment. The demand of order is changeable and uncertain in real environment. It is convenient for scheduling transforming it into static data, but can't get the advantage on time. This paper proposes a real time vehicle scheduling on the study of traditional scheduling and discusses the model structure and the key technology for the real time system that establishes the base for develop teal time system.