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1.
Optimisation of activity within the structural constraints defined by the preceding work, by varying the substituents on phenyl in the acid fragment (10 variations), the nature of the group fulfilling the dimethyl function (three variations), the central linking group (four variations) and the presence or absence of a 4-fluoro substituent in the alcohol fragment, has led to achiral compounds as active as bioresmethrin against houseflies and mustard beetles. Statistical analysis of the effects has shown that particular combinations, for instance the cyclopropyl form of dimethyl with a central E-alkene group (but not a central ether group), lead to higher activity than expected. 4-Fluoro substitution enhances activity more strongly against mustard beetles. Difluorocyclopropyl compounds are on average slightly more active than cyclopropyl analogues.  相似文献   
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ABSTRACT:   The effects of the different catching methods (gillnet, longline, harpoon) on sensory, chemical (pH, total volatile base nitrogen, K -value) and microbiological (total viable count [TVC]) changes in pike perch Sander lucioperca stored in ice were investigated. The same soaking time was used for both gillnet and longline fishing. The catching method had considerable influence on the freshness quality of pike perch. The acceptable shelf life was 15 days for pike perch caught by gillnet, and 22 days for longline and harpoon. The initial concentrations of inosine monophosphate (2.4 μmol/g) in pike perch caught by gillnet were significantly lower ( P  < 0.05) than longline (4.1 μmol/g), and especially by harpoon (16.7 μmol/g). However, the initial K -values for fish caught by harpoon were significantly ( P  < 0.05) lower (24.36%) than fish caught by longline and gillnet (57.69%, 64.41%, respectively). The average K , Ki, G and H -values at rejection day in terms of sensory assessment were approximately 90, 98, 156 and 40%, respectively, for all catching methods during ice storage. However, TVC reached 7.0 log cfu/g after approximately 11 days of storage for fish caught by gillnet, 19 days for fish caught by longline and 8 days for fish caught by harpoon. The result of this study suggests that the best catching method for preserving the freshness of pike perch is longline, based on the data obtained from the sensory and microbiological analysis.  相似文献   
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One of the fundamental aspects of the economic and social viability of the local and regional areas of Turkey is the degree to which they have access to the wider national economic and social system. Accessibility is, therefore, of major social, economic and political significance in Turkey and it directly affects Turkey's regional growth and the quality of life in local communities. However, the importance of the economic and social viability of the communities is increasingly complicated in the face of rapid global economic recession. It is argued that countries need to develop knowledge economies to compete successfully as knowledge is a critical factor for growth. This paper integrates accessibility and the importance of knowledge creation in understanding local and regional economic development. This empirical study has shown that although there is a high correlation between the accessibility index and the population figures of Turkey, accessibility to knowledge differs across Turkish provinces.  相似文献   
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Oil rose flowers were stored at 0 °C in four different packaging materials [plastic box + stretch film (PB + SF), Xtend®, Smartbag® and polyethylene (PE)] for 60 days. During storage, weight loss, O2 and CO2 concentrations in the packages, petal color and sensorial attributes were investigated besides essential oil content and composition. Storage duration and packages had significant (p < 0.01) effects on weight loss. At the end of storage, the lowest weight loss was in PE package (1.696%) whereas the highest weight loss was in Xtend® (10.081%). The essential oil content was significantly (p < 0.01) affected by storage duration and packages. In addition, the essential oil contents obtained from all packages for a storage period of 10 days and the essential oil contents obtained from unstored (control) petals were included in the same group. At the end of storage, the essential oil contents decreased by 91.3, 57.7, 80.0 and 64.3% in PB + SF, Xtend®, Smartbag® and PE packages, respectively as compared to control. In addition, storage duration and package types significantly (p < 0.01) affected petal color, O2 and CO2 concentrations in the packages and sensorial scores. The concentration of citronellol, a main component of rose oil, increased in all packages during storage of 10 days in comparison to the control group while it varied in other storage durations and package types. However, nerol and geraniol were lower than the control group during storage while concentrations of nonadecane, heneicosane and eicosane were higher. In conclusion, loss of oil yield and quality, due to various reasons and particularly due to fermentation in oil rose from the harvest of petals to their distillation, can be minimized with storage of petals in all package types for up to 10 days.  相似文献   
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The objective of the present research was to develop an effective and practical method for hybrid seed production in safflower, by inducing male sterility with gibberellic acid (GA3). Seeds of the spiny line ‘5‐154’ and the non‐spiny variety ‘Dincer 5‐118’ were sown in alternate rows and the plants of the non‐spiny female variety were exposed to various concentrations of GA3 for male sterility induction. Three successive sprays (75, 82 and 89 days after sowing) of 100 p.p.m. of GA3 to safflower buds of <0.5 cm diameter at a pre‐meiotic interphase stage resulted in reduced pollen viability from 81.6‐6.7% compared with the control. An average hybrid seed percentage of 80.7% (87.5% in the secondary heads), identified by the use of the spiny‐capitulum marker variety ‘5‐154′, was obtained. The GA3 treatments did not significantly affect the production of viable achenes. The results showed that GA3 could be successfully used as a chemical hybridizing agent in hybrid safflower production.  相似文献   
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Summary The effects of 10 volatile oils and their main compounds on potato sprout growth were investigated in vitro. Sprout growth was inhibited especially by the volatile oils fromOriganum onites, Rosa damascena, Carum carvi, Mentha piperita, Echinophora tuneifolia andCoriandrum sativum. The major compound of volatile oils was carvacrol (78.2%) inO. onites, citronellol (46.7%) inR. damascena, S-(+)-carvone (54.9%) inC. carvi, menthol (44.1%) inM. piperita, α phelladrene (45.9%) inE. tuneifolia and linalool (76.5%) inC. sativum. The results showed that some volatile oils rich in monoterpenic compounds such as carvacrol, citronellol, geraniol, nerol and S-(+)-carvone were able to prevent the growth of sprouts and extend the storage-life of the potato tubers.  相似文献   
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Chemical composition of grape canes   总被引:1,自引:0,他引:1  
In this study, chemical composition of canes which were sampled from ten different grape cultivars was investigated. For the determination of total phenolics, total flavanols and total flavonol contents, canes were analyzed spectrophotometrically. The phenolic compositions of the canes, including caffeic acid, catechin, p-coumaric acid, epicatechin, gallic acid, luteolin and trans-resveratrol were detected by HPLC. The anthron method was used for the determination of total carbohydrate content. The minerals such as K, P, Ca, Fe, Mg and Zn were determined by ICP-OES. All the parameters investigated in this study significantly changed depending on the cultivar. The results showed that grape canes as agricultural wastes from commercial viticultural activities represent a potentially important source of phenolics, minerals, carbohydrates and proteins. Therefore the grape canes may be used as an easily accessible source of natural antioxidants and food supplement.  相似文献   
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Breeding for the improvement of the ideal plant type of sesame   总被引:1,自引:0,他引:1  
H. Baydar 《Plant Breeding》2005,124(3):263-267
The objective of this study was to improve the ideal type of sesame, by performing pedigree selection applied to segregating generations of crosses of genotypes with contrasting characters. In the segregating F2 population, the progeny were classified into eight types according to the combinations of carpel number per capsule, capsule number per axil and branching habit. Progeny of individual F2 plants including a particular type were advanced to the F6 generation. It was possible to improve the lines with eight types at the end of the selection process. Some types, especially bicarpels, monocapsule, branch (BMB) and bicarpels, tricapsules, branch (BTB), were considered as ideal plant types in breeding for high‐yielding varieties. While the low‐yielding type quadricarpels, tricapsules, non‐branch (QTN) was the highest in oil content (49.3%), the high‐yielding type BMB was the lowest (43.2%), Although the QTN‐type had the lowest content of oleic acid (41.3%) and the highest content of linoleic acid (43.1 %), the bicarpels, monocapsule, non‐branch (BMN) type had the highest content of oleic acid (48.4%) and the lowest content of linoleic acid (36.6%), Total tocopherol varied between 175.6 and 368.9 mg/kg in the seed oil of the sesame types. The best high‐yielding type BMB was one of the types containing less tocopherol.  相似文献   
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