Effects of the severity and timing of basal leaf removal on the amino acids profiles of Sauvignon Blanc grapes and wines

The effects of the severity and timing of leaf removal(LR) on the amino acids of Sauvignon Blanc grapes and wines were studied during the 2017 growing season. High-performance liquid chromatography(HPLC) was used to analyze the amino acids profiles of grape berries and wines. The basal leaves were removed at three time points(40, 56 and 72 days after flowering, named LR40, LR56 and LR72, respectively) at two severity levels(one at which the first, third, and fifth basal leaves of each shoot were removed(50% level); and another at which the first six basal leaves were removed(100% level)). The results showed that leaf removal had little impact on total soluble solids(°Brix), titratable acidity, pH or berry weight. The LR72-50% treated grapes had higher berry weight, titratable acidity and °Brix than those of the other treatments. The highest concentrations of total amino acids and of total amino acids except proline were detected in LR72-50% treated grapes(2 952.58 and 2 764.36 mg L~(-1), respectively); the lowest were detected in LR72-100% treated grapes(2 172.82 and 2 038.71 mg L~(-1), respectively). LR72-50% treatment significantly promoted the synthesis of aspartic acid, serine, arginine, alanine, aminobutyric acid and proline at both severity levels for grapes, the concentrations of all of these amino acids were increased relative to the control concentrations. The LR72-50%, LR40-100% and LR72-100% treated wines had higher total amino acids concentrations and higher concentrations of some individual amino acids, such as arginine, alanine and serine, than did the control wines. Of all the amino acids studied, glycine, tyrosine, cysteine, methionine and lysine were not significantly influenced by the timing or severity basal defoliation in grapes and wines. The present study reveals the effects of the timing and severity of leaf removal on the amino acids profiles of grapes and wines.     

大豆苷和染料木苷对山羊乳腺上皮细胞增殖的影响

The experiment was aimed to study the effects of different concentrations of daidzin and genistin on proliferation of goat mammary gland epithelial cells, the test was adopted the method of MTT. The results revealed that the ng level of concentration had more effects on cells than the μg level of concentration. And when cells were treated with the two materials for 48 h, the effects were greater than for 24 and 72 h. The highest poteney was detected in daidzin (10 ng/mL) and genistin (10 and 100 ng/mL) compared with the control group.     

植物营养学在经济林研究中的运用

植物营养学是研究植物对营养物质的吸收、运输、转化和利用规律及植物与外界环境之间营养物质和能量交换的学科,在农林生产中运用广泛.文中结合植物营养学科的研究概况及趋势,简要介绍其在经济林品种选育、营养诊断与施肥、树体调控及抗逆研究中的运用,并对今后经济林营养学的研究方向进行了探讨.     

双汇"瘦肉精"事件冷思考:行业需自律

“瘦肉精”（包括盐酸克伦特罗、菜克多巴胺、沙丁胺醇等），是一类肾上腺类神经兴奋剂。长期食用含有“瘦肉精”的畜产品，会使人出现四肢震颤、惊慌、头痛、恶心、呕吐等症状，对高血压、心脏病、甲状腺功能亢进、青光眼、糖尿病及前列腺肥大等疾病患者危害更大。     

分块子空间追踪算法

压缩传感理论是一种充分利用信号稀疏性或者可压缩性的全新信号采样理论。该理论表明，通过采集少量的信号测量值就能够实现可稀疏信号的精确重构。本文在研究现有经典重构算法的基础上，提出结合图像分块思想和回溯思想的分块子空间追踪算法（Block Subspace Pursuit, B_SP）用于压缩传感信号的重构。该算法以块结构获取图像，利用回溯过程实现支撑集的自适应筛选，最终实现图像信号的精确重构。实验结果表明，在相同测试条件下，该算法的重构效果无论从主观视觉上还是客观数据上都有不同程度的提高。     

鲍曼不动杆菌雏鸡分离株CCGGD201101的分离、鉴定及致病性研究简

试验旨在鉴定吉林省某雏鸡孵育基地病死雏鸡组织中分离出的1株致病性菌CCGGD201101株并测定其致病性。对疑似致病菌进行生理生化试验、16S rDNA测序鉴定，并人工接种昆明鼠，测定其半数致死量，验证细菌毒力。经鉴定该菌为鲍曼不动杆菌（Acinetobacter baumannii）。以鲍曼不动杆菌CCGGD201101分离株为研究对象，并以鲍曼不动杆菌标准株（ATCC 19606）为对照，测得半数致死量，进一步证明鲍曼不动杆菌病死鸡分离株CCGGD201101具有较强致病性。     

吉林市6种常见绿篱植物滞尘能力的比较

比较了吉林市6种绿篱植物在不同季节和不同时间的滞尘能力。结果表明,树种不同,单位叶面积滞尘量有差异,金山绣线菊和金焰绣线菊滞尘能力较强,同种植物的滞尘能力为夏季>春季;在达到饱和之前,随着时间的延长,单位叶面积滞尘量增加,雨后第10天滞尘量对总滞尘量的贡献最大,雨后14 d达到饱和。     

不同配比南极磷虾粉饲料对网箱养殖俄罗斯鲟生长及氟累积的影响

配制南极磷虾粉替代饲料中鱼粉比例分别为0%、10%、20%、30%的4组饲料饲喂俄罗斯鲟(Acipenser gueldenstaedtii)200 d后,分析南极磷虾粉替代部分鱼粉对网箱养殖俄罗斯鲟生长和鱼体组织氟残留的影响。结果表明:(1)随着南极磷虾粉替代比例的升高,俄罗斯鲟的末重、增重、特定生长率、蛋白质效率先上升后下降,饲料系数先降低后升高,10%组显著高于对照组和其它试验组(P0.05);(2)实验结束时,俄罗斯鲟肌肉、肝脏和鱼鳔的氟浓度低于检测限,但鳃、皮、脊骨和背骨呈现剂量浓度效应,各试验组较对照组显著升高(P0.05)。综上所述,在本实验条件下,在俄罗斯鲟饲料中加入10%比例的南极磷虾粉时获得最佳生长效果和较低的组织氟累积。     

水资源系统与社会经济生态系统协调性评价

水资源系统与社会经济生态系统的协调性已越来越引起关注。首先利用主成分分析法,分别求出水资源系统与社会经济生态系统的综合评价指数,然后采用距离协调度模型得到两个系统间的协调度值,对两个系统的协调性进行了定量分析。以山东省为例,计算了2001-2012年两系统的协调度值。结果表明:两系统综合评价指数总体趋势上升;两系统发展虽然不同步,但协调性良好。     

细胞质雄性不育三系油菜杂交种南种北制实施效果

细胞质雄性不育三系杂交种是我国油菜最主推的品种，但其不育系在南方秋播制种会出现微量花粉，给种子纯度带来极大风险。利用青海气候资源进行春播制种，能克服不育系的微粉问题，且制种产量高，种子商品性好。