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991.
利用AFLP构建大白菜高密度遗传连锁图谱   总被引:2,自引:0,他引:2  
以大白菜根肿病抗性材料CR Shinki DH系和感病性材料大白菜自交系94 SK杂交F2的138个单株作为构建遗传图谱的群体。利用AFLP技术通过45对引物筛选共获得835个AFLP标记,应用其中608个AFLP标记和6个与抗根肿病基因CRb紧密连锁的AFLP标记转化成的SCAR标记构建了一张包含556个标记位点、10个连锁群、覆盖基因组长度为795 cM的连锁图谱。该图谱中每个连锁群上的标记数在10~83个之间,平均图距在0.86~4.34 cM之间,连锁群长度在43.4~120.9 cM之间。CRb基因定位于第3连锁群9 cM的范围内。  相似文献   
992.
Tree growth and the increase in inorganic nutrients during a growing season were studied in 3-year-old, container-grown ‘Fuyu’ persimmon trees with different levels of fruit-load. Fruit-load was varied by adjusting the leaf–fruit ratio to 10, 20, 30, and 60 on July 5. Some trees were completely defruited. The whole trees were harvested on November 5 of that year, and increases in dry weight and inorganic elements in different tree parts during the season were measured. A lower leaf–fruit ratio resulted in a higher yield but also decreased fruit weight, soluble solids, and fruit color. Dry weight of the aerial woods and root increased significantly with a greater ratio. However, total dry weight including the fruits was higher in the lower ratio trees than in the higher ratio trees; the weight of a tree that maintained the ratio of 10 was 35% higher than a tree without fruit. Fruits accounted for 62% of total dry weight when the ratio was 10 and 27% when the ratio was 60. The leaf–fruit ratio did not significantly alter the total increase in P, K, Ca, and Mg content. N tended to decrease with an increasing leaf–fruit ratio. Of the total increases of N, P, and K during the season, the fruits accounted for 30%, 50%, and 54% at the ratio of 20, respectively, and the percentages increased to 44, 81, and 74 at the ratio of 10. The inorganic element content in the aerial woods and root tended to increase with greater ratios, especially in the root. When trees were defruited, N and K increases in the root accounted for 44% and 35% of the total increase, respectively. These results indicated that persimmon orchard fertilization programs with different fruit-load levels should accommodate the proportion of nutrients partitioned to fruits that are removed permanently from the tree.  相似文献   
993.
A rapid and efficient colorimetric method based on the use of Fast Blue B-salt (FBB) was established to select catechin-rich tea trees (Camellia sinensis L.). The catechin levels measured by the colorimetric method under optimized reaction conditions correlated closely with estimations by high-performance liquid chromatography (HPLC) analysis. The FBB colorimetric method was successfully used to classify 160 tea trees on the basis of their catechin contents into rich and poor lines. HPLC analysis of the FBB-selected tea tree extracts showed them to contain (−)-epigallocatechin 186 mg/g in tea tree line HR-29, (−)-epicatechin 43.7 mg/g in HR-82, (−)-epigallocatechin gallate 4.32 mg/g in HR-29, and (−)-epicatechin gallate 0.22 mg/g in HR-52. Classification of tea trees from the Hadong region into catechin-rich and -poor trees was independent of the growing season. Thus the FBB colorimetric method could find application as a reliable tool in screening and selection of tea trees on the basis of their catechin content.  相似文献   
994.
Choi H  Takahashi D  Kono K  Kim E 《Science (New York, N.Y.)》2010,330(6010):1512-1515
Supersolidity, the appearance of zero-viscosity flow in solids, was first indicated in helium-4 torsional oscillator (TO) experiments. In this apparatus, the irrotationality of the superfluid component causes it to decouple from the underlying normal solid, leading to a reduction in the resonant period of the TO. However, the resonant period may be altered for reasons other than supersolidity, such as the temperature dependence of the elastic modulus of solid helium. Superimposing rotation onto oscillatory measurements may distinguish between supersolidity and classical effects. We performed such simultaneous measurements of the TO and the shear modulus, and observed substantial change in the resonant period with rotational speed where the modulus remained unchanged. This contrasting behavior suggests that the decrease in the TO period is a result of supersolidity.  相似文献   
995.
Obesity is a common nutritional disorder in cats and it increases the risk factors for various diseases. The aim of this study is to suggest a method for the evaluation of feline obesity using computed tomography. The attenuation range from -156 to -106 was determined as the range of feline abdominal adipose tissue. With this range, total (TAT), visceral (VAT) and subcutaneous (SAT) adipose tissues were measured. The best correlation between the adipose tissue in cross-sectional image and entire abdomen volume was obtained at the L3 and L5 levels. The mean VAT/SAT ratio was 1.18±0.32, which was much higher than in humans. The cats with an overweight body condition had a significantly lower VAT/SAT ratio than cats with an ideal body condition. This technique may contribute to both the clinical diagnosis and the experimental study of feline obesity.  相似文献   
996.
997.
The coloration of poly(lactic acid) (PLA) fiber with 18 carbocyclic monoazo disperse dyes bearing a hydrolyzable phthalimide ring fused to the aromatic ring of their diazo components has been investigated. The phthalimidyl nitrogen atom was substituted with either a n-butyl, sec-butyl, or isopropyl group, while the adjoining phenyl ring bore a substitution pattern typical of commercial colorants. There was a broad correlation between percentage dye exhaustion onto PLA and that onto polyester (PET) fiber, although significant differences in certain instances were apparent with no clear trends regarding dye structure. Attempts to explain the observed percentage exhaustion values by mapping them to calculated partition coefficient or solubility parameter values were unsuccessful. Wash fastness was relatively good compared to that of some conventional disperse dyes applied to PLA. As was found to be the case with PET, the wash fastness of dyes on PLA tended to be highest when their diazo ring was substituted with electron acceptors.  相似文献   
998.
999.
This article portrays a case study in Yogyakarta, Indonesia which looks into the dynamic relationship between communities and the effectiveness of the implementation of community-based forest management (CBFM) policies and its programme, and particularly on how local institutions deal with the shifting dynamics of these policies. As there is currently an absence of research in this area, this research therefore focuses on how the local community implements policy, builds relationships with other stakeholders, and strengthens local community institutions.

CBFM has been implemented in Yogyakarta since 1995 and during that time, the central government has been changing the policy for five times. At this point, this article argues that CBFM should rely on local institutions and deal with the shifting dynamics of policies. The terms of institutions can be considered to include formal institutions, such as Constitution, government laws, charters, decrees and statutes, and informal institutions, such as code of conducts, customs, local knowledge and social expectations. Furthermore, in selected communities, it is clear that the local communities can apply their informal institutions as an important component and value of traditional systems and significantly involved in forest management sustainability and establish the formal institutions simultaneously.  相似文献   

1000.
In this study, photocatalytic degradation of bisphenol A (BPA) was investigated using two types of catalysts (TiO2 and ZnO) with various metal ion concentrations and amounts of added H2O2. A kinetic test was performed to observe the changes of BPA over time under UV irradiation in a photocatalytic reactor. Experimental results demonstrated that degradation efficiency of ZnO was higher than that of TiO2. The degradation rate increased as catalyst dosage increased until reaching optimum dosage, after which degradation rate decreased. The addition of H2O2 improved the degradation efficiency of BPA, with the degradation efficiency increasing with the amount of H2O2. All metal ions, including Fe2+, Ni2+, and Cu2+, inhibited the degradation of BPA by ZnO at natural pH, whereas Fe2+ and Ni2+ enhanced degradation efficiency of BPA at acidic pH. Comparison of BPA degradation with H2O2 only, ZnO/H2O2, Fe2+/H2O2, and ZnO/Fe2+/H2O2 revealed that Fe2+/H2O2 was more efficient than other processes at lower pH (pH?=?3.44), whereas ZnO/H2O2 the most efficient at higher pH (pH?=?6.44). These results indicate that ZnO/H2O2 process was observed to be the most efficient of all processes. Degradation efficiency of BPA by ZnO was also influenced by additional parameters, including H2O2 concentration, metal ions, and solution pH.  相似文献   
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