Green tea polyphenols supplementation alters immunometabolism and oxidative stress in dairy cows with hyperketonemia

Peripartal cows often experience negative energy balance, and are therefore prone to suffering from metabolic diseases such as hyperketonemia, which causes financial losses in dairy farms. This study aimed to investigate the effect of green tea polyphenol (GTP) supplementation during the periparturient period on production performance, oxidative stress and immunometabolism in dairy cows with hyperketonemia. One hundred Holstein cows were assigned to GTP (0.2 g/kg DM; n = 50) or control (without GTP; n = 50) group based on body weight, previous milk yield, and parity on d 15 before expected parturition. Subsequently, 10 cows with hyperketonemia were selected from each group, according to blood β-hydroxybutyric acid (BHBA) concentration between 1.2 and 2.9 mmol/L from 2 to 3 d postpartum. All cows were fed a close-up diet and a lactation diet with or without GTP supply from 15 d prepartum until 30 d postpartum. Milk and blood samples were obtained from 20 cows selected with hyperketonemia on 10, 20, and 30 d postpartum. Compared with control cows, greater milk yield and lower somatic cell count were observed in GTP cows. The GTP group had lower concentrations of BHBA, free fatty acids, cholesterol, triglyceride, reactive oxygen species, malondialdehyde, and hydrogen peroxide, greater concentrations of glucose, lower activities of aspartate aminotransferase, alanine aminotransferase, and glutamyl transpeptidase, alongside greater activities of superoxide dismutase, glutathione peroxidase, and total antioxidant capacity. Additionally, GTP supplementation up-regulated concentrations of interleukin-6 and interleukin-10, but down-regulated concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-2, interleukin-8, and interferon-γ in plasma. Greater concentrations of plasma immunoglobulin G were also detected in the GTP group. Overall, the data suggested that GTP supplementation from 15 d prepartum to 30 d postpartum improved the milk yield and health status in cows with hyperketonemia during early lactation.     

南方冬种马铃薯杀秧机的设计

根据南方冬种马铃薯机械化收获的农艺要求,仿照马铃薯播种机所形成的垄形,设计一种适合于南方冬种马铃薯的杀秧除草设备。利用Solid Work设计传动系统、刀辊和刀具,并对刀具进行有限元受力分析。受力仿真分析及刀辊动平衡试验结果表明,马铃薯杀秧机能够满足设计的要求。     

基于供水调节的水库削峰能力

水库防洪调度计算时,一般以汛限水位作为水库调洪初始水位。由于供水等功能的影响,水库并非时刻处于蓄满状态,汛限水位是水库调洪初始水位的上限值,汛限水位以下的空库容将发挥拦洪作用。针对典型供水水库,通过分析库容系数和供水系数与蓄水率的分布特征之间的关系、蓄水率与水库对洪水的削峰率之间的关系,研究库容系数和供水系数对削峰率的影响。实例计算表明,考虑供水调节的影响后,水库的库容系数和供水系数对削峰率的影响不可忽略,且削峰率与供水系数成二次函数关系。因此,类似水库的下游河道在防洪设计时应充分考虑库容系数和供水系数对削峰率的影响。     

育种咨询系统中的水稻杂交后代性状预测

杂交育种是一个很复杂的组合过程。由于指导育种的遗传学原理还远不够完善,因此,在实践中更多的是依赖育种家的经验和技巧,从而造成了育种工作中一定程度上的盲目性。为了提高育种效率,有必要发展一套为育种工作服务的咨询系统。利用它协助育种家收集数据、分析育种过程。本文重点阐述水稻杂交咨询系统研制中的杂交后代性状预测方法及原理。     

Protective Effect of Sulforaphane on Reproductive Function of Male Mice with Cadmium Poisoning

The study was aimed to explore the protective effect of sulforaphane (SFN) on the reproductive function of male mice with cadmium poisoning.40 healthy clean grade male Kunming mice were randomly divided into four groups:control group (H₂O),cadmium chloride group (2.3 mg/kg CdCl₂),sulforaphane group (10 mg/kg SFN),sulforaphane + cadmium chloride group (10 mg/kg SFN+2.3 mg/kg CdCl₂),and continuous administration for 10 d,all mice were executed by dislocated cervical vertebra at 2 d after the last administration,and then the pathologic changes of testicular tissues,organ coefficient of testicle and epididymis,sperm quality and concentration of testosterone were tested.Additionally,the contents of GSH and MDA,and the activities of T-SOD in testis were also detected at the same time. Compared with the control group,pathology damages were observed in cadmium chloride group,organ coefficient of testis and epididymis,sperm quality and levels of testosterone extremely significantly decreased (P<0.01),the activities of T-SOD and GSH content were extremely significantly decreased (P<0.01),and the concentration of MDA was extremely significantly enhanced (P<0.01).Compared with the control group,the activity of T-SOD and concentration of GSH in sulforaphane group were significantly increased (P<0.05),and the concentration of MDA was not significant different between the control group and sulforaphane group (P>0.05).While compared with the cadmium chloride group,the sperm motility rate and sperm total count in sulforaphane and cadmium chloride group were extremely significantly increased (P<0.01),the organ coefficient of testicle and epididymis was increased significantly (P<0.05),the concentration of GSH and activity of T-SOD in testicular tissue were extremely significantly increased (P<0.01),and the concentration of MDA was extremely significantly decreased (P<0.01).The results indicated that sulforaphane had the protection effect on reproduction function of male mice with cadmium poisoning.     

苹果果实表皮总蛋白提取及双向电泳方法的优化

以苹果果实表皮为试材,采用3种方法提取果实表皮总蛋白,并对双向电泳(2-DE)操作体系进行优化。结果表明:改良酚提法适于苹果果实表皮总蛋白的提取,优化后的2-DE分离体系为预制IPG胶条18cm pH 4~7,上样量600μg,改进后的等电聚焦程序,浓度16%的分离胶,适于苹果果实表皮总蛋白的2-DE分离。     

外源乙烯和1-甲基环丙烯处理对采后胡萝卜品质的影响

以胡萝卜为试材,采用乙烯及乙烯受体抑制剂(1-甲基环丙烯)处理,通过对贮藏60d后胡萝卜的品质劣变率(长须根率、腐烂指数、出薹率)、外观指数、可溶性糖含量及多酚氧化酶活性进行测定,研究了1-MCP对胡萝卜采后贮藏品质的影响。结果表明:1-MCP结合手洗贮藏可抑制胡萝卜贮藏期间的品质劣变率、抑制可溶性糖含量的损失、保持较高的外观指数及抑制多酚氧化酶(PPO)活性。手洗后贮藏则可有效改善胡萝卜贮藏期间的表皮褐变问题。     

苹果树种植对黄土旱塬土壤蒸发的影响

以陕西长武旱塬为例,分别对研究区农地和5个不同林龄(9、12、16、19 a和23 a)苹果园的土壤剖面氢氧稳定同位素进行测定,利用Craig-Gordon模型定量估算其土壤平均蒸发量,并基于“空间换时间”方法分析果园种植及生长对土壤蒸发的影响。结果表明：农地及9、12、16、19、23 a林龄苹果园的土壤蒸发量均随苹果树的种植及生长呈现先减少再增大的趋势,年均蒸发量分别为129、104、89、119、128、136 mm;苹果园的土壤蒸发量变化与叶面积指数呈显著负相关(R=-0.713);苹果园种植的前中期(9～12 a)土壤蒸发量随叶面积指数增加逐渐减小,而在中后期(12～23 a)深层土壤水被大量消耗造成的干旱胁迫使得果树叶面积减少,从而导致林下土壤蒸发量又逐渐增大。     

THE DEVELOPMENT OF COMPUTER AIDED NORM OF WORKING HOUR PLANNING SYSTEM

Based on Group Technology, part families of the norm of working hour are formed according to the similarity among components. With the progressive regerssion, the models of the norm of working hour are built for every part family. A computer aided norm model building program and a computer aided norm of working hour planning system are developed. The system is successfully integrated with CAD/CAPP system. Some examples of the model building and calculation results are illustrated as well.