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91.
0号柴油水溶性成分对僧帽牡蛎脂质过氧化的影响 总被引:2,自引:0,他引:2
在实验条件下,将僧帽牡蛎分别置于含有0.5、2、5 mg·L-10号柴油水溶性成分的海水中,在污染后1、4、7、11、15 d采样,15 d后转入清洁海水中进行6 d的恢复实验,采样,观察消化腺和鳃脂质过氧化的程度。结果表明:(1)正常生理条件下消化腺和鳃也有一定程度的脂质过氧化,消化腺显著高于鳃;(2)脂质过氧化的程度随污染时间的延长而增加,并存在一定的剂量-效应关系,可作为监测海洋石油污染的生物标志物;(3)解除污染后,脂质过氧化恢复到对照水平。 相似文献
92.
以Visual Basic 6.0这种高级语言开发多要素系统为例,主要介绍在处理具有相关性的各要素组成多要素系统时需要注意的问题及其解决方法,同时阐述了系统相关ActiveX控件的调用及其使用方法。此外,本多要素系统也实现了外部应用程序Microsoft Office对象库Access 2000的引用,同时完成与本多要素系统相关的程序代码。 相似文献
93.
Andrew D. Graves Edward H. Holsten Mark E. Ascerno Kenneth P. Zogas John S. Hard Dezene P.W. Huber Robert A. Blanchette Steven J. Seybold 《Forest Ecology and Management》2008
Field bioassays were conducted in south-central Alaska in a stand of Lutz spruce, Picea
0;×
0;lutzii, to determine whether a semiochemical interruptant (verbenone and trans-conophthorin) and/or a defense-inducing plant hormone (methyl jasmonate, MJ) could be used to protect individual standing trees from bark beetle attack. During two experiments (initiated in May 2004 and 2005, respectively), attacks by Ips perturbatus on standing trees were induced by using a three-component aggregation pheromone (ipsenol, cis-verbenol, and ipsdienol) and prevented by using the interruptant. In 2005, treatments from 2004 were repeated and additional treatments were evaluated by using MJ spray or injection with and without the interruptant. Aggregation began before 3 or 7 June, and attack density was monitored through 3 or 16 August. During both years, tree mortality caused by I. perturbatus was recorded twice (in August, and in May of the following year). In both experiments, attack density was greatest on trees baited with the three-component attractive pheromone, but was significantly reduced by addition of the semiochemical interruptant to trees baited with the attractant. There were no significant differences in attack density between attractant
0;+
0;interruptant-treated trees and unbaited trees. In 2004, mortality was highest among attractant-baited trees, whereas addition of the interruptant significantly reduced the level of initial (10 week post-treatment) and final (54 week post-treatment) mortality. In 2005, no significant reduction in attack density occurred on trees baited with the attractant when MJ was sprayed or injected. The highest initial (10.6 week post-treatment) and final (49.4 week post-treatment) mortality was observed among trees that had been injected with MJ and baited with the attractant. Mortality at the final assessment was significantly lower in all other treatment groups. As in 2004, addition of the interruptant to attractant-baited trees significantly reduced the level of final mortality compared to attractant-baited trees. MJ was not attractive or interruptive to I. perturbatus or associated bark beetles in a flight trapping study. However, MJ-treated trees (sprayed or injected) exuded copious amounts of resin on the bark surface. Anatomical analyses of felled trees from four treatment groups [Tween (solvent)-sprayed, MJ-sprayed, Tween-injected, and MJ-injected
0;+
0;attractant baited] showed that treatment with MJ increased the number and size of resin ducts produced following treatment. These analyses also revealed a reduction in radial growth in MJ-treated trees. Our results show that during both years, treatment with a simple, two-component interruptant system of verbenone and trans-conophthorin significantly reduced I. perturbatus attack density and tree mortality on attractant-baited trees and provided a full year of protection from bark beetle attack. 相似文献
94.
Fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of C0t-1 DNA and genomic DNA from the cultivated rice. The coverage percentage (%) and size (Mb) of C0t-1 DNA in O. sativa, O. officinalis, and O. meyeriana were 47.1 ±0.16, 38.61 ±0.13, 44.38±0.13, and 212.33± 1.21,269.42 ± 0.89, 532.56± 1.68 Mb, respectively. The coverage percentage and size of genomic DNA from O. sativa in O. officinalis and O. meyeriana were 91.0, 93.6% and 634, 1 123 Mb, respectively, in which 365 and 591 Mb in O. officinalis and O. meyeriana were from O. sativa genomic DNA, but not from repetitive sequences of O. sativa, and the uncoverage genome size in O. officinalis and O. meyeriana were 64 and 78 Mb, respectively. In addition, karyotype analysis was conducted based on the signal bands of C0t-1 DNA in O. sativa, O. officinalis, and O. meyeriana. The results showed that highly and moderately repetitive sequences in Oryza genus were conserved as the functional genes during evolution. The repetitive sequences reduplication may be one of the important causes of the genome enlargement of O. officinalis and O. meyeriana, and O. officinalis genome enlarged more slowly when compared with O. meyeriana. Based on the above results, it is concluded that O. officinalis and O. meyeriana were formed by reduplication, rearrangement, and gene selective loss during the evolution process. 相似文献
95.
利用FAO-56 Penman-Monteith法计算四川省4个分区1960—2010年逐月的潜在蒸散量(ET0),采用贡献率法分析ET0近50 a来变化成因。结果表明:整个四川省、四川盆地和盆周山地日照时数和风速下降对ET0的负贡献超过平均、最高和最低气温上升以及相对湿度下降对ET0的正贡献,使ET0呈下降趋势;川西北高原平均、最高和最低气温上升以及相对湿度下降对ET0的正贡献超过风速和日照时数下降对ET0的负贡献,使ET0呈上升趋势;川西南山地平均、最低气温、日照时数和风速的下降对ET0的负贡献超过了最高气温上升和相对湿度下降对ET0的正贡献,使ET0呈下降趋势。四川省和四川盆地日照时数下降是ET0下降的主要原因,盆周山地和川西南山地风速下降是ET0下降的主要原因,川西北高原最低温度上升是ET0上升的主要原因。 相似文献
96.
97.
98.
广西多站点参考作物蒸散量时空变化分析 总被引:1,自引:0,他引:1
基于广西20个气象观测站点1957—2001年的逐月气象资料,采用Penman-Monteith公式计算各站点逐月、逐年参考作物蒸散量(ET0),采用变差系数和年际极值比分析ET0的年际变化特征,应用累积滤波器法、Ken-dall秩次相关法、R/S分析法分析ET0的变化趋势。研究结果表明,桂中ET0年际变化最剧烈,桂南ET0年际变化最小。岩溶发育地区的ET0的年际变化比非岩溶发育略显剧烈,但相差不大。20个站点中,5%站点的ET0呈显著上升趋势,95%站点的ET0呈下降趋势(下降趋势显著的站点占63.1%)。与1957—2001年相比,ET0呈上升趋势的站点由5%增加到未来的35%,且非岩溶地区ET0呈上升趋势的站点数大于岩溶地区。 相似文献
99.
C. Vanderghem Y. BrostauxN. Jacquet C. BleckerM. Paquot 《Industrial Crops and Products》2012,35(1):280-286
A Box-Behnken experimental design and response surface methodology were employed to optimize the pretreatment parameters of a formic/acetic acid delignification treatment of Miscanthus
0;×
0;giganteus for enzymatic hydrolysis. The effects of three independent variables, namely cooking time (1, 2 and 3
0;h), formic acid/acetic acid/water ratio (20/60/20, 30/50/20 and 40/40/20) and temperature (80, 90 and 107
0;°C) on pulp yield, residual Klason lignin content, concentration of degradation products (furfural and hydroxymethylfurfural) in the black liquor, and enzymatic digestibility of the pulps were investigated. The major parameter influencing was the temperature for pulp yield, delignification degree, furfural production and enzymatic digestibility. According to the response surface analysis the optimum conditions predicted for a maximum enzymatic digestibility of the glucan (75.3%) would be obtained using a cooking time of 3
0;h, at 107
0;°C and with a formic acid/acetic acid/water ratio of 40/40/20%. Glucan digestibility was highly dependent on the delignification degree. 相似文献
100.
A.M. Villegas-Fernández J.C. SilleroA.A. Emeran F. FloresD. Rubiales 《Field Crops Research》2011,124(1):59-65
The aim of this work was to identify Vicia faba germplasm resistant both to rust and chocolate spot. A collection of 43 accessions of V. faba previously identified as chocolate-spot resistant was evaluated for rust and chocolate spot resistance in Egypt and in Spain. The genotype and genotype
0;×
0;environment (GGE) biplot analyses allowed the selection of 11 accessions resistant to both diseases in those locations. These 11 accessions were evaluated for rust in an additional field trial in Spain, all performing better than the susceptible check. The joint analysis of the 11 accessions in the four field trials where they had been evaluated revealed no significant effects either for genotype, environment or the genotype
0;×
0;environment interaction. They are hence promising sources of resistance, both for their low severities and their stable responses across the studied environments. This collection was also tested under controlled conditions against the Egyptian and the Spanish isolates of rust present in the field trials further underlining the stable performance of these genotypes. Finally, the effect of previous infection with chocolate spot on rust resistance was assessed under controlled conditions and no influence of it was found. 相似文献