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171.
S. K. Bishnoi B. Kumar C. Rani K. S. Datta P. Kumari I. S. Sheoran R. Angrish 《Biologia Plantarum》2006,50(1):135-137
Two pigeonpea [Cajanus cajan (L.) Millsp.] genotypes, a salt tolerant Manak and a salt sensitive ICPL 88039 were subjected to stress treatment of 3 mM
boron, 60 mM NaCl and boron + NaCl at the seedling stage. Radicle and plumule proteins were analyzed by SDS-PAGE. Boron treatment
increased 28.3 kDa proteins in plumule and 38.3 and 51.9 kDa proteins in radicle of Manak, however, there was no specific
protein in ICPL 88039 either in plumule or in radicle. In NaCl treatment 95.6 kDa proteins appeared in plumule and 67.5 kDa
proteins in radicle of Manak. Conversely content of some proteins decreased by boron treatment alone or in combination with
NaCl although they were present in the controls. Thus, 54.3 kDa protein disappeared in ICPL 88039 plumule, 68.4 kDa in Manak
radicle and 28.1 kDa in ICPL 88039 radicle. 相似文献
172.
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175.
Recent histories of six productive lakes in the Irish Ecoregion based on multiproxy palaeolimnological evidence 总被引:2,自引:2,他引:0
D. Taylor C. Dalton M. Leira P. Jordan G. Chen L. León-Vintró K. Irvine H. Bennion T. Nolan 《Hydrobiologia》2006,571(1):237-259
Palaeolimnological data from six mesotrophic, eutrophic and hypertrophic lakes in the Irish Ecoregion, in the form of microfossil
(cladocera, diatoms and pollen) and sediment chemistry data from radiometrically dated sediment cores, were used to reconstruct
past variations in lake water quality and catchment conditions. Basal sediments from sediment cores from the six sites ranged
in age from the late 18th century to the early 20th century. A weighted averaging partial least squares regression model was
developed to reconstruct past epilimnetic total phosphorus concentrations. The results indicate that all but one of the study
sites currently are in a far more productive state compared with the beginning of the sediment core record and that those
same five lakes have experienced accelerated enrichment post c. 1980. Two of the sites demonstrated long-term enrichment,
in one case beginning in the late 19th century, while both eutrophication and oligotrophication have occurred at three sites.
The results highlight the difficulties in applying a general temporal end-point for reference conditions and demonstrate that
productive lakes in the Irish Ecoregion have complex, locally specific and often long histories of enrichment. These may not
be responsive to reduced external loadings of phosphorus and, as a result, restoration could prove particularly challenging.
The results also provide evidence of the ways in which palaeolimnological techniques can assist implementation of the EU Water
Framework Directive.
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献
176.
The first stages zoeas of Quadrella maculosa Alcock, 1898, Q. serenei Galil, 1986, Tetralia rubridactyla Garth, 1971, and Trapezia richtersi Galil & Lewinsohn, 1983, are described and illustrated. Setal differences between the Quadrella zoeas are not recorded, but they can be separated on the spinulation of the dorsal spine (present in Q. maculosa absent in Q. serenei). The first stage zoea of Q. maculosa is compared with that of Tetralia rubridactyla and Trapezia richtersi. But although Quadrella and Tetralia appear superficially similar in that both have two pairs of lateral carapace spines (vs. one pair in Trapezia), other observations imply that Tetralia zoeas may have closer affinities with Trapezia rather than with Quadrella. However, this appears to contradict recent phylogentic relationships based on adult morphology. 相似文献
177.
Y. J. Cho S. Y. Kim J. Kim E. K. Choe S. I. Kim H. J. Shin 《Biotechnology and Bioprocess Engineering》2006,11(3):230-234
In this study, we describe a one-step chemoenzymatic reaction for the production of natural blue pigments, in which the geniposide
from Gardenia extracts is transformed by glycosidases to genipin. Genipin is then allowed to react with amino acids, thereby
generating a natural blue pigment. The β-glycosidases, most notably isolase (a variant of β-glucanase), recombinant β-glucosidase,
Cellulase T, and amylases, were shown to hydrolyze geniposide to produce the desired pigments, whereas the α-glycosidases
did not. Among the 20 tested amino acids, glycine and tyrosine were associated with the highest dye production yields. The
optimal molar ratio of geniposide to glycine, two reactants relevant to pigment production, was unity. The natural blue pigments
produced in this study were used to dye cotton, silk, and wool. The color yields of the pigments were determined to be significantly
higher than those of other natural dyes. Furthermore, the color fastness properties of these dyes were fairly good, even in
the absence of mordant. 相似文献
178.
179.
Despite the potential benefits of utilising enzyme-based treatments to remove specific non-cellulosic polysaccharide components from flax fibre prior to spinning, attempts to date have not proved successful. At present, techniques employing conventional chemical reagents are solely employed within this industry. To establish the feasibility of incorporating an enzyme treatment stage within a novel process sequence, small-scale laboratory test protocols have been developed and employed to screen the performance of a range of commercial enzyme formulations on commercial dew-retted flax rovings. Thermal analysis and physical testing permitted rapid assessment and the best-performing treatment sequences, based on Pectinex AR and Pentopan 500 BG, respectively (Novozymes A/S, Bagsvaerd, Denmark) were then successfully scaled-up for industrial spinning trials. The results of these trials have shown that treatment with a chelating agent followed by pectinase and peroxide bleaching processes is capable of producing good quality yarn. The compositional and structural changes occurring in the fibre at each stage of treatment were detected using derivative thermogravimetry, and revealed quantitative changes in weight loss, decomposition temperature and peak widths in response to process steps. Assessment of chemical and physical performance data for the yarns obtained indicates that such a process may have commercial applications, supplementing the repertoire of traditional techniques and reagents available to the industry. 相似文献
180.