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71.
High malting quality of barley (Hordeum vulgate L.) relies on many traits, such as β-amylase and limit dextrinase activities and β-glucan and protein fraction contents. In this study, interval mapping was utilized to detect quantitative trait loci (QTLs) affecting these malting quality parameters using a doubled haploid (DH) population from a cross of CM72 (six-rowed) by Gairdner (two-rowed) barley cultivars. A total of nine QTLs for eight traits were mapped to chromosomes 3H, 4H, 5H, and 7H. Five of the nine QTLs mapped to chromosome 3H, indicating a possible role of loci on chromosome 3H on malting quality. The phenotypic variation accounted by individual QTL ranged from 8.08% to 30.25%. The loci of QTLs for β-glucan and limit dex-trinase were identified on chromosomes 4H and 5H, respectively. QTL for hordeins was coincident with the region of silica eluate (SE) protein on 3HS, while QTLs for albumins, globulins, and total protein exhibited overlapping. One locus on chromosome 3H was found to be related to β-amylase, and two loci on chromosomes 5H and 7H were found to be associated with glutelins. The identification of these novel QTLs controlling malting quality may be useful for marker-assisted selection in improving barley malting quality.  相似文献   
72.
Treatment of lake sediments with salts is a promising approach for preventing phosphorus release from sediments. Five 35-d treatments of undisturbed sediment cores in the East Lake, Wuhan, China were applied under anoxic conditions: nothing added (control), Al2(SO4)3 added, FeCl3 added, CaCl2 added, and NaNO3 added. To identify changes in the P binding sites in the sediment caused by the treatments, different P binding forms were extracted from the sediment before and after the treatments. We found that the mean P release rates for anoxic treatments with Al2(SO4)3, FeCl3, CaCl2 and NaNO3 were -0.6, 0.03, 0.6 and 2.6 mg/(m^2·d), respectively, while the P release rate with no additives was 7.3 mg/(m^2·d). In suboxic conditions, the concentration of total phosphorus (TP ge 657 mg/kg) in sediment was much lower than that of untreated sediment (TPaverage 688 mg/kg) and treatments with salts (TP(Al2(SO4)3) 793 mg/kg, TP(FeCl3) 781 mg/kg, TP(NaNO3) 802 mg/kg, TP(CaCl2) 747 mg/kg). We also found that adding CaCl2 prevented P release because of apatite formation and because PCa (Ca bound P) increased at the sediment surface. Addition of Fe^3+ and NO3^- to the sediment increased the amounts of PFe. Mn (Redox-sensitive P, mostly Fe and Mn compounds), since iron oxide has the ability to combine P. Addition of Al2(SO4)3 increased the fraction of PAl, Fe (P bound to metal oxides (Al, Fe)) and decreased the P and Fe in the water above the anoxic sediment, showing the greater ability orAl in binding P. The results showed that Al2(SO4)3, FeCl3, CaCl2 and NaNO3 all had an effect in controlling phosphorus release. The effect was related to the forms of phosphorus existing in the sediment before treatment and the forms resulting after adding the four reagents. The combination of Al^3+ or Fe^3+ with NO3^- promises to be a reasonable chemical treatment for increasing the P retention capacity of sediments in eutrophic lakes. If chemical treatment is combined with bioremediation, the aim of environmental repair may be achieved.  相似文献   
73.
We present an empirical model for the effective thermal conductivity (ETC) of a polymer composite that includes dependency on the filler size distribution-chosen as the Rosin-Rammler distribution. The ETC is determined based on certain hypotheses that connect the behavior of a real composite material A, to that of a model composite material B, filled with mono-dimensional filler. The application of these hypotheses to the Maxwell model for ETC is presented. The validation of the new model and its characteristic equation was carried out using experimental data from the reference. The comparison showed that by using the size distribution law a very good fit between the equation of the new model (the size distribution model for the ETC) and the reference experimental results is obtained, even for high volume fractions, up to about 50%.  相似文献   
74.
本文根据连分数和共轭分数的某些定理,介绍了一种满足给定传动比所需精度要求的轮齿齿数直接选择法,描述了相应的计算机程序,分析比较了计算结果。  相似文献   
75.
Heat stable fraction (HSF) of alkaline phosphatase (ALP) was evaluated as an adjunct to CA 125 as a tumour marker for epithelial ovarian cancer in a follow-up study. In our study group 63.4% of patients had elevated HSF levels (≥10U/L) and 93.3% had elevated CA 125 levels (>35U/mL). The sensitivity of CA 125 and HSF was 93.3% and 63.3% respectively. The decline in the activity of HSF, over the pre-op levels was highly significant after the first (p=0.001) chemotherapy cycle and significant after the second and third cycles (p<0.029). Thereafter, HSF activity was almost undetectable. The decrease in CA 125 levels over the pre-op levels was significant after the first, second, third (p<0.001) and fourth (p<0.034) chemotherapy cycle. HSF can be used alone or as an adjunct to CA 125 in screening and monitoring patients of ovarian carcinoma especially in remote areas where sophisticated facilities are not available and in patients in which CA 125 levels are not raised preoperatively.  相似文献   
76.
为提高图像的压缩效率,提出一种基于Sobel算子和非线性混合有理插值的图像压缩方法。将Sobel算子应用于图像的轮廓提取,利用二元Newton-Thiele型向量连分式建立有理插值曲面,然后对插值函数进行重采样,按要求实现图像压缩。实验结果表明,该方法能有效应用于数字图像的压缩处理,具有计算简单、易于编程实现等优点,是一种较实用的方法。  相似文献   
77.
为提高光伏发电系统孤岛检测性能,在带正反馈的主动频移(Active Frequency Drift with Positive Feedback,AFDPF)法的基础上,将初始斩波因子设置为公共耦合点(Point of Common Coupling,PCC)电压频率的函数,设计一种变初始斩波因子的AFDPF法.基于Qf0×Cnorm坐标系分析比较两种AFDPF法的检测盲区,并在MATLAB/Simulink环境下,对单相光伏并网发电系统的孤岛检测进行仿真.结果表明:使用AFDPF法时,反馈系数的大小与孤岛检测速度成正比,与检测盲区成反比;改进的AFDPF法可以根据负载的性质改变初始扰动的方向,检测盲区的位置也会随之向上或向下移动;改进的AFDPF法不仅适用于容性负载和感性负载,而且可减小检测盲区和加快检测速度.  相似文献   
78.
由W(?)O型微乳液的生成给出一个简单处理模型,经几个步骤的数字处理得出γ=-常数×1/a2g((?))的γ与 a.(?)的 关系式,因此可解释某些相平衡.  相似文献   
79.
研究了3个Lucas数乘积和的变换问题,给出了r次(r=2s)恒等变换公式及r=4时的变换.  相似文献   
80.
目的:探讨在监测血清脑钠肽水平下,短期使用注射用重组人脑利钠肽治疗急性心力衰竭或慢性心力衰竭急性发作的临床效果。方法:48例急性心力衰竭患者根据是否使用注射用重组人脑利钠肽分为常规组和注射用重组人脑利钠肽组,对比两组治疗的临床效果和超声心动图情况,并监测BNP水平。结果:治疗7d后,注射用重组人脑利钠肽组临床有效率明显好于常规组(81.7%vs61.6%,P〈0.05),左室射血分数明显高于常规组(51±6)%vs(46±5)%,(P〈0.01),且血清脑钠肽水平明显降低(498±209)pg/mL vs(642±318)pg/mL,(P〈0.01),血清脑钠肽下降水平和左室射血分数提高水平差异有统计学意义(P〈0.05),有效者治疗后左室射血分数提高及血清脑钠肽下降均强于无效者(P〈0.01)。结论:在血清脑钠肽指导下短期应用注射用重组人脑利钠肽有助于改善急性心力衰竭患者的临床症状和心功能。  相似文献   
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