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41.
The effect of hydroxypropyl-β-cyclodextrin (HPβCD) in the dyeing of polyamide fabric was investigated under conditions that mimic industrial dyebaths where dye mixtures are used. The dyes used were Telon Red BN, Telon Yellow A-2R, and Telon Blue RR. The blue dye complexed with HPβCD whereas the other dyes did not do so under the conditions used. The dyeing results were compared with those obtained using a traditional retarding agent, Albegal B. The exhaustion dyeing data showed that HPβCD mainly affected the dyeing behavior of the blue dye that became encapsulated. In the case of the yellow and red dyes, changes in the overall kinetics of dyeing were observed, resulting in modified exhaustion profiles. In comparison, Albegal B retarded the blue dyeing process and increased the rate of exhaustion of the yellow dye while the exhaustion curve of red dye remained unchanged. The color uniformity of the dyed polyamide was improved when HPβCD was used. This resulted from the more controlled exhaustion rate during the critical phase of the dyeing process. 相似文献
42.
I. Urretavizcaya L. G. Santesteban B. Tisseyre S. Guillaume C. Miranda J. B. Royo 《Precision Agriculture》2014,15(1):111-129
Early definition of oenologically significant zones within a vineyard is one of the main goals of precision viticulture, as it would allow an increase in profitability through the adaptation of agronomic practices to the specific requirements of each zone, and/or segregation of the harvest into different batches to produce wines with different qualities. The aim of this work was to evaluate whether early grape sampling is a relevant tool for within-vineyard zone definition. The study was carried out in 2010 and 2011 in a 4.2 ha vineyard, where a grid of 60 sampling points was defined. 300-berry samples were picked from each sampling point after veraison and at harvest, post-veraison information being used to define zones within the vineyard after fuzzy k-means analysis and subsequent application of a zoning procedure that took into account membership degree and neighbourhood criteria. Two variations of the zoning procedure were used, standard (StdZ) and top (TopZ) zoning. Each was designed to meet different requirements of wineries; StdZ gave the same oenological relevance to all the zones, and TopZ differentiated the zones producing “top class” grapes, minimizing the within-zone variability in the top-class zone. Grape composition obtained at harvest from the zones delineated post-veraison was compared. Zone delineation using post-veraison data was proved to be oenologically relevant, provided sampling is performed once veraison is completed. The two zoning algorithms designed were shown to be suitable for objective zone delineation according to the goals intended for each. 相似文献
43.
Janaina O Luna Manoel A A Santos Edison L Durigon Jo?o P Araújo Júnior José M B Duarte 《Journal of zoo and wildlife medicine》2003,34(4):414-415
Esophageal-pharyngeal fluids from 53 free-ranging marsh deer (Blastocerus dichotomus) captured for a research program in the state of Mato Grosso do Sul, Brazil, were assayed for tuberculosis. Total DNA was extracted. amplified by polymerase chain reaction using specific primers for Mycobacterium tuberculosis complex (M. tuberculosis, M. bovis, M. microti, and M. africanum), and observed by agarose gel electrophoresis stained with ethidium bromide. All samples were negative. This, along with necropsy and histopathology data, suggests that these animals are not shedding and probably do not have active disease. 相似文献
44.
Thinner pod walls might contribute to increased yield potential and adaptation of lupins. Fourteen autumn‐sown genotypes of Lupinus albus L. were evaluated over 2 years at four sites in southern Chile. Pod wall proportion (PWP), pod wall specific weight (WSW) and five other pod‐related characters were measured to estimate their genetic variation, heritability across years and sites, and genotypic and phenotypic correlations among the characters. Ranges for PWP and pod WSW were 22.9−43.1% and 16.4−37.4 mg/cm2, respectively. PWP in cultivated L. albus was similar to that reported in L. angustifolius; however, specific weight was substantially lower. Highly significant genotypic effects were found for both characters. Broad sense heritabilities were high for PWP (0.63) and moderate for pod WSW (0.46). These characters were significantly correlated, more so genotypically (rg = 0.67) than phenotypically (rph = 0.36). Selection for low PWP should lead to lower pod wall thickness or density, both of which contribute to pod WSW. Nevertheless, selection for pod WSW could achieve further reductions, particularly if practised among low PWP materials. 相似文献
45.
Sexual plant reproduction is a complex process that involves a series of interactions between the male gametophyte and the
different cell types of the pistil. These interactions are believed to direct the pollen tube growth until its final target,
the embryo sac. Arabinogalactan proteins are complex proteoglycans that are believed to be involved in these processes. The
pistil is enriched in these highly glycosylated proteins and we provide results that show the selective presence of different
AGP epitopes at the surface of the cells or in the ECM of the tissues that correspond exactly to the pollen tube growth pathway
in Amaranthus hypochondriacus and Actinidia deliciosa. We also show that in Actinidia deliciosa, which is a dioecious plant
with the male flowers having rudimentary ovaries where fertilization does not occur, there is no presence at all of the epitopes
recognised by the monoclonal antibodies utilized in this study.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
46.
Selection for Increased Seed Nitrogen Accumulation in Common Bean: Implications for Improving Dinitrogen Fixation and Seed Yield 总被引:1,自引:0,他引:1
Estimates of N2 fixation in segregating populations of bean plants based on 15N-isotope methods are technically demanding and expensive; therefore, indirect measures based on related traits including total seed N were used to select for improved N2 fixation and yield. In 1985, six populations of F2-derived F3 families resulting from six parental lines crossed to a common tester were grown in field trials on a low-N soil. In 1986, 25 selected half-sib families and two populations of full-sib F4 families were grown under similar conditions. Parents and a non-nodulating soybean line were included both years. Narrow sense (HNS) heritability estimates based on parent-offspring regressions ranged from 0.57 for total seed N to 0.39 for shoot biomass in one population, but were near zero for all measured traits in a second population. Among the criteria used to identify parental lines with superior potential for producing progenies with high total seed N, testcross population means combined with estimates of realized heritability were the most reliable. Selection of the best F3 families for total seed N resulted in F4 families with increased total seed N and higher seed yields, while seed protein percentage was unchanged. When plants are grown on low-N soils, selection for total seed N offers a useful alternative to selection for increased N2 fixation based on 15N-isotopic or total-N-difference method. 相似文献
47.
Summary The character of determinate plant growth has not been reported for chickpea and has not been observed in the world germplasm collection at ICRISAT, Patancheru, India. A determinate growth habit would be desirable where growing conditions often lead to excessive vegetative growth. We attempted to generate this trait by mutation breeding. Seeds of the cultivar ICCV 6 were exposed to varying irradiation treatments, M1 and M2 populations were raised, and in the latter one plant was detected that showed the determinate growth habit and female sterility. The character of determinate growth segregated in a postulated digenic epistatic 3:13 fashion in the F2 and confirmed its digenic mode of inheritance in the F3 and F4. The symbol cd is proposed for the allele conditioning for determinancy and Dt for the allele expressing the determinate trait. Continued mutation breeding with this and other material may result in identifying fully fertile, determinate plant types.Abbreviations DT -
determinate
- IDT -
indeterminate
ICRISAT Journal Article No. 1396. 相似文献
48.
Quantitation of transgenic plant DNA in leachate water: real-time polymerase chain reaction analysis
Gulden RH Lerat S Hart MM Powell JR Trevors JT Pauls KP Klironomos JN Swanton CJ 《Journal of agricultural and food chemistry》2005,53(15):5858-5865
Roundup Ready (RR) genetically modified (GM) corn and soybean comprise a large portion of the annual planted acreage of GM crops. Plant growth and subsequent plant decomposition introduce the recombinant DNA (rDNA) into the soil environment, where its fate has not been completely researched. Little is known of the temporal and spatial distribution of plant-derived rDNA in the soil environment and in situ transport of plant DNA by leachate water has not been studied before. The objectives of this study were to determine whether sufficient quantities of plant rDNA were released by roots during growth and early decomposition to be detected in water collected after percolating through a soil profile and to determine the influence of temperature on DNA persistence in the leachate water. Individual plants of RR corn and RR soybean were grown in modified cylinders in a growth room, and the cylinders were flushed with rain water weekly. Immediately after collection, the leachate was subjected to DNA purification followed by rDNA quantification using real-time Polymerase Chain Reaction (PCR) analysis. To test the effects of temperature on plant DNA persistence in leachate water, water samples were spiked with known quantities of RR soybean or RR corn genomic DNA and DNA persistence was examined at 5, 15, and 25 degrees C. Differences in the amounts and temporal distributions of root-derived rDNA were observed between corn and soybean plants. The results suggest that rainfall events may distribute plant DNA throughout the soil and into leachate water. Half-lives of plant DNA in leachate water ranged from 1.2 to 26.7 h, and persistence was greater at colder temperatures (5 and 15 degrees C). 相似文献
49.
Duarte RT Carvalho Simões MC Sgarbieri VC 《Journal of agricultural and food chemistry》1999,47(1):231-236
The objective of this research work was to fractionate bovine blood, collected hygienically in a slaughterhouse, into blood plasma protein concentrate, red blood cell concentrate, globin isolate, and a carboxymethylcellulose-heme iron (CMC-heme) complex. All four fractions were studied for proximate composition and amino acid and mineral contents. The nutritive value of plasma protein concentrate and globin isolate was comparatively studied using rat bioassays. The amino acid content in plasma protein concentrate is well balanced and produced net protein utilization and net protein ratio equivalent to 95% those of casein. Globin isolate ( approximately 91% protein) is deficient in isoleucine and S-containing amino acids and was unable to support rat growth at 10% concentration in the diet. Red blood cell concentrate and the isolated CMC-heme complex were good sources of bioavailable iron. Iron availabilities for CMC-heme and whole blood cell concentrate, related to ferrous sulfate as 100%, were 64 and 70%, respectively. 相似文献
50.
Determination of Organic Mercury in Biota, Plants and Contaminated Sediments Using a Thermal Atomic Absorption Spectrometry Technique 总被引:1,自引:0,他引:1
M. Válega S. Abreu P. Pato L. Rocha A. R. Gomes M. E. Pereira A. C. Duarte 《Water, air, and soil pollution》2006,174(1-4):223-234
A simple, rapid procedure for the determination of organic mercury in sediments, plants and fish tissues has been developed and validated. Extraction and separation of organic mercury compounds from the sample matrix was achieved by an established procedure based on an acid leaching of the sample (H2SO4/KBr/CuSO4), followed by extraction of the organic mercury halide with toluene and back-extraction with an aqueous solution of thiosulphate. Detection and quantification of mercury, in the liquid extracts, was made by atomic absorption spectrometry (AAS), following thermal decomposition of the sample. The method was evaluated using Certified Reference Material (CRM) BCR 463 (tuna fish), BCR 580 (estuarine sediment), IAEA-140TM (sea plant homogenate) and NRCC TORT-2 (lobster hepathopancreas). The recovery factors for organic mercury in all tested CRM were between 81–107%. The precision of the method has relative standard deviations of less than 10% for sediments and fish tissues and of less than 16% for plant material. The method was successfully applied to natural samples of sediments, plants, macroalgae and fish tissues collected from an estuarine ecosystem and could, therefore, be used for routine analyses. 相似文献