42.8％露娜森悬浮剂防治葡萄白腐病的田间药效试验

作者以42.8％露娜森悬浮剂对葡萄白腐病进行田间防治试验.结果表明,42.8％露娜森悬浮剂对葡萄白腐病的防治效果较好,2000倍液药量第3次药后14 d防治效果依然能达到90.8％,3000倍液防效同健达2500倍液相当,明显高于大生800倍液的防效.     

长江中游两个湖泊沉积物中枝角类微化石密度的垂直变化研究

湖泊沉积物中保存的枝角类微化石不仅能够重建湖泊枝角类的群落演替历史,还能反映人类活动的干扰强度。本文研究了龙感湖、武昌湖沉积物中枝角类微化石组成、密度垂直变化以及人类活动干扰对其影响。结果表明：在龙感湖和武昌湖沉积物中,分别鉴定出9种和12种枝角类卵鞍。龙感湖沉积物中的枝角类总卵鞍密度（LG1: 2.22 ind./(g·dw);LG2: 2.57 ind./(g·dw)）高于武昌湖（1.63 ind./(g·dw),象鼻溞壳刺的平均密度（LG1: 360.53 ind./(g·dw);LG2: 558.26 ind./(g·dw)）显著高于武昌湖（1.52 ind./(g·dw)）。自20世纪60年代以来,武昌湖沉积物中枝角类的优势类群由裸腹溞属、尖额溞属种类向裸腹溞属、盘肠溞属种类转变。龙感湖在1950年前,枝角类卵鞍的优势种群为盘肠溞属种类;而1950以后,其优势类群由盘肠溞属、裸腹溞属种类向象鼻溞属种类转变。两个湖泊沉积物中枝角类卵鞍和象鼻溞壳刺密度的垂直变化与湖泊富养化过程和渔业养殖历史相一致。结果表明,人类活动的干扰强度影响了长江中下游湖泊沉积物中枝角类微化石的组成和密度变化。     

赤点石斑鱼与鞍带石斑鱼杂交子一代肌肉营养成分分析与评价

为分析赤点石斑鱼与鞍带石斑鱼杂交子一代的营养组成,参照国家标准,测定了体质量(182.84±29.35) g杂交石斑鱼肌肉的常规营养成分、氨基酸和脂肪酸组成,并对肌肉营养价值进行了评定。试验结果显示,杂交石斑鱼肌肉水分、粗蛋白、粗脂肪和灰分的含量分别为(74.07±0.71)%、(21.52±0.78)%、(4.03±0.15)%和(1.29±0.07)%。肌肉鲜样中测定了17种氨基酸,总量为(19.88±0.15)%;必需氨基酸和鲜味氨基酸总量分别为(8.64±0.13)%和(7.64±0.16)%,必需氨基酸指数为85.19,必需氨基酸组成符合联合国粮农组织/世界卫生组织标准。肌肉鲜样中含有17种脂肪酸,饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸分别占肌肉脂肪酸总量的(27.63±1.15)%、(22.75±1.22)%和(32.59±1.90)%,其中二十二碳六烯酸和二十碳五烯酸占肌肉脂肪酸总量的(19.27±1.27)%。研究表明,赤点石斑鱼与鞍带石斑鱼杂交子一代具有较高营养价值,可作为新品种进行开发。     

Jagged1 knocking down in endothelial cells accelerates PDGF induced proliferation and migration of vascular smooth muscle cells in rats

AIM: To investigate the effect of Jagged1 expression in endothelial cells (EC) on platelet derived growth factor (PDGF) induced proliferation and migration of vascular smooth muscle cells (VSMC) in rat.METHODS: Rat aorta EC was inoculated in the lower chamber and VSMC were in the upper chamber of the cell coculture system. Three groups were divided: control, sicontrol and siJagged1. The EC Jagged1 protein expression was assayed by Western blotting to evaluate small RNA interfering (RNAi) efficiency. After the cells were cocultured with PDGF for 24 h, the proliferation and migration of VSMC were respectively evaluated by ［3H］-TdR incorporation and migrating cells counting. Protein expression of α-SM-actin in VSMC was assayed by Western blotting. RESULTS: The Jagged1 protein expression in EC was significantly lower in siJagged1 group than that in control group (0.26±0.02 vs 0.67±0.02, P<0.05), and no statistic significance was observed between control and sicontrol groups. The VSMC ［3H］-TdR incorporation and migration were higher in PDGF +siJagged1 group than those in PDGF group {［3H］-TdR incorporation (23 074±2 702) counts·min-1·well-1 vs (16 442±1 803)counts·min-1·well-1, n=5, P<0.05; migration (27±4) cells/field vs (15±3)cells/field, n=5, P<0.05}. The α-SM-actin protein in VSMC was lower in PDGF + siJagged1 group than that in PDGF group (0.25±0.06 vs 0.49±0.04, n=3, P<0.05).CONCLUSION: Jagged1 knock down in rat EC accelerates PDGF induced proliferation and migration of VSMC. These results suggest that Jagged1 expression in EC plays an important role in maintaining VSMC contract phenotype and inhibiting VSMC overgrowth after arterial injury.     

黄瓜果实曲直性评价方法及相关性分析

以48份黄瓜品种为试材,采用刨分法测量其果实弯曲度,通过黄瓜果实形态指标和相关分析可知弯曲度与果长、果柄长、果柄长/果长、果长/果横径显著正相关,与种腔大小、种腔/果横径极显著负相关,与果横径显著负相关,与果肉厚不相关。依据果形指数和弯曲度对黄瓜进行了分级。筛选出顺直品种8份,次弯曲品种9份,弯曲品种31份。     

Suppression of Rice Stem Borer, Chilo suppressalis by Mass Trapping Using Synthetic Sex Pheromone in Paddy Field

Suppressing effects of mass trapping using synthetic sex pheromone with main active ingredients of Z-11-hexadece-nal, Z-13-octadecenal and Z-9-hexadecenal on the rice stem borer, Chilo suppressalis were investigated during the flight periods of the overwintering and 1^st generation in the paddy area of 60 ha in 1999. Population density of C. suppressalis in the pheromone-treated fields was lower than that in control. The egg masses decreased by 74. 39% and population size of adult males of the 1^st generation decreased by 61.64% in the treated fields as compared to control. Meanwhile, the damage by C.suppressalis larvae was significantly lower in the treated fields than control (t-test, P=0.05). Percentages of brownish leaf sheath, dead heart, and white head in the treated fields were decreased by 70.90%, 57.01% and 44.30%, respectively in contrast to control. The present study demonstrated that mass trapping to C. suppressalis using synthetic sex pheromone shows great potential as an alternative measure in an environment-friendly pest management and at the same challenging the insecticide use that has some environment impacts.     

基于高光谱技术的茶鲜叶含水率检测与分析

茶鲜叶含水率是茶叶加工业中衡量茶叶品质的一个重要指标。为了实现茶叶加工过程中茶鲜叶含水率的快速检测,本文提出了一种应用高光谱技术分析茶鲜叶含水率的无损检测方法。通过对茶鲜叶高光谱图像感兴趣区域光谱数据的提取,利用4种不同的算法对原始数据进行预处理,采用逐步回归分析法对预处理后的数据提取特征波长,并采用多元线性回归法、偏最小二乘回归建立特征波长和茶鲜叶含水率定量分析模型。研究结果表明,经过卷积平滑处理后的正交信号校正的预处理结合逐步回归分析法所建立的偏最小二乘回归茶鲜叶含水率预测效果最佳,模型校正集、交叉验证集和预测集的相关系数分别为0.8977、0.8342和0.7749,最小均方根误差分别为0.0091、0.0311和0.0371。由此可见,高光谱技术能有效的实现茶鲜叶含水率的检测,这为茶叶加工业中衡量茶叶品质提供了新的检测方法。     

土壤水分状况对猕猴桃叶片蒸腾速率影响研究

针对传统方法在计算猕猴桃叶片蒸腾速率时,存在结果不准确,修正率不高问题,为此,提出一种新参数修正法解决上述问题.基于高光谱传感器对猕猴桃叶面积蒸腾速率动态模拟分析方法,构建蒸腾模型;运用该模型分析各因素对蒸腾速率的影响,通过函数修正方法获得土壤水分状况系数,从而实现猕猴桃叶面积蒸腾速率的准确计算.为了验证方法的有效性,...     

锥齿轮齿顶修缘技术研究及应用

针对现有锥齿轮齿顶修缘人工打磨方法效率低、一致性差以及专用机床柔性差、调整困难等问题,研究一套锥齿轮齿顶修缘技术,对现有加工中心进行改造,设计合理的刀具、夹具,制定合理的工艺参数,选择典型的锥齿轮零件进行齿顶修缘工艺试验,将修缘误差控制在0.3mm内。该技术具有新颖性、创造性和实用性的特点,具有推广应用价值。     

保水剂与肥料互作及保水缓/控释肥料研究展望

保水剂在农业上的作用日益重要,肥料与保水剂一体化使用是水肥调控的重要技术,是肥料研究的国际前沿。保水剂是吸水量超过自身重量数百倍以上的亲水性高聚物。保水剂一般分为天然的,合成的及半合成的。保水剂与肥料可以通过物理混合、包膜或化学合成三种方式结合为一体化的保水缓/控释肥料。保水剂具有吸水吸肥功能,保水剂可吸附大量中性分子,对阳离子养分也有较强吸附作用,对阴离子养分吸附弱。肥料种类与盐浓度影响保水剂的吸附作用与膨胀能力。保水缓/控释肥料在土壤中对肥料养分有延迟释放作用。保水缓/控释肥料可改善土壤持蓄水分和水肥交互作用,促进植物对养分的吸收和作物增产。保水缓/控释肥料发展方向是包膜和化成保水缓/控释肥料。保水缓/控释肥料湿润及养分控释机理研究也需要加强。