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11.
12.
In the present study we have investigated the effect of exogenous cyclitols on accumulation of their galactosides and raffinose
family oligosaccharides (RFOs) in maturing smooth tare (Vicia tetrasperma [L.] Schreb) seeds. Feeding d-pinitol to pods of smooth tare increased the amount of free d-pinitol and its galactosides: galactopinitol A, galactopinitol B, di- and trigalactopinitol A in seeds. Similarly, feeding
d-chiro-inositol, which does not occur naturally in Vicia seeds, resulted in the transport of this cyclitol in the seed, and caused accumulation of high levels of d-chiro-inositol galactosides (fagopyritol B1, B2 and B3). Accumulation of both cyclitols and their galactosides drastically reduced
accumulation of verbascose and, to a lesser extent, stachyose and di-galactosyl- myo-inositol. Feeding d-chiro-inositol also decreased accumulation of di- and tri-galactosyl pinitols, naturally occurring in seeds. Inhibition of RFOs
accumulation by elevated levels of free cyclitols indicates competition between biosynthesis of both types galactosides, and
similarity of both biosynthetic pathways in smooth tare seeds. 相似文献
13.
Matías Reolid Christian Gaillard Federico Olóriz Francisco J. Rodríguez-Tovar 《Facies》2005,50(3-4):529-543
Two main types of microbial encrustation were identified in Middle Oxfordian to lowermost Kimmeridgian deposits in the Prebetic Zone (southern Spain), showing existing relationships between skeletal content, fabric and morphology of these organosedimentary structures. Laminated planar and concentric encrustations relate to peloidal fabrics (mainly constituted of microbes = microbial laminated fabrics s. str. and microbial oncoids s. str.), as well as to dense microbial fabrics periodically colonized by encrusting foraminifera (microbial laminated fabrics with nubeculariids and microbial oncoids with nubeculariids). Sedimentation rates, substrate stability and grain size, as well as illumination, influenced microbial growth pattern as major controlling factors in low-energy conditions, and forced palaeogeographic and stratigraphic patterns of distribution. Significant encrustation was identified in terrigenous-poor lithofacies from the middle (Transversarium-Bifurcatus zones) to the outer (Transversarium-Bimammatum zones) shelf in the Prebetic Zone. Rare-to-absent encrustation characterized terrigenous-rich deposits (Bimammatum and Planula zones) in the area. 相似文献
14.
Historical Ecology on Sandoy, Faroe Islands: Palaeoenvironmental and Archaeological Perspectives 总被引:1,自引:1,他引:0
Ian T. Lawson Mike J. Church Tom H. McGovern Símun V. Arge James Woollet Kevin J. Edwards Freddy J. Gathorne-Hardy Andrew J. Dugmore Gordon Cook Kerry-Anne Mairs Amanda M. Thomson Guðrún Sveinbjarnardótti 《Human ecology: an interdisciplinary journal》2005,33(5):651-684
We present palaeoenvironmental, geomorphological, archaeological, and place-name data which allow a holistic assessment of
the history of landscape change on Sandoy, Faroe Islands, especially in terms of the changes that occurred in response to
the colonization of the island by humans. In contrast to other situations in the North Atlantic region, there is considerable
continuity in the patterns and processes of landscape evolution across the initial settlement horizon. Many of the characteristic
features of post-settlement North Atlantic landscapes—absence of trees, widespread blanket mires, high rates of soil erosion—were
already in place when the first people arrived. Although human impact on Sandoy appears to have been light, conversely, the
unusual environment forced major alterations of the subsistence economy imported by the colonists. Settlement-era archaeological
records suggest that, from the start, patterns of resource use differed substantially from the regional norm, and these differences
became amplified over time as the Faroese economy created a locally sustainable cultural landscape. 相似文献
15.
16.
Manuel Pardo-de-Santayana Javier Tardío Michael Heinrich Alain Touwaide Ramón Morales 《Economic botany》2006,60(2):159-181
El Ingenioso Hidalgo, Don Quijote de la Mancha, by Miguel de Cervantes (1547–1616), is the best-known work of Spanish literature. We searched this and the other works of Cervantes for references to plants, plant communities, and products. These texts capture the customs, thoughts, beliefs, and traditions of Spanish culture in the late 16th and early 17th centuries. They also repeat literary themes of ancient Greek and Roman literature. Plant citations were grouped in three categories: plants as part of the environment, useful plants, and plants in symbolic expressions. A total of 150 species were registered, 102 of which appear inDon Quijote. The taxa with the highest frequency of occurrence areVitis vinifera, Phoenix dactylifera, Triticum aestivum, Laurus nobilis, Rosa spp.,Olea europaea, Quercus ilex, andArundo donax. The number of references to plants and the variety of species seem to attest to a sound and intimate knowledge of plants, their relevance as a landscape feature, and their utility. Many edible, ornamental, technological, and medicinal plants are referred to either explicitly or implicitly. Several species are mentioned in a figurative sense through references to their symbolic meaning, in proverbs, idiomatic expressions, metaphors, or by mentioning them in comparisons and literary figures of speech. 相似文献
17.
Sílvia G. Pereira Fernando P. Lima Nuno C. Queiroz Pedro A. Ribeiro António M. Santos 《Hydrobiologia》2006,555(1):185-192
Geographical patterns in the distribution of epifaunal crustaceans (Amphipoda, Isopoda and Tanaidacea) occurring with dominant
macroalgal species were investigated along the Portuguese rocky coast. Three regions, each encompassing six shores, were studied.
Algal species were selected according to their geographical distribution: Mastocarpusstellatus and Chondrus crispus (north); Bifurcariabifurcata (north-centre); Plocamiumcartilagineum and Cystoseiratamariscifolia (centre-south); Corallina spp. and Codiumtomentosum (entire coast). Multivariate techniques were used to test for differences in crustacean assemblage composition between sub-regions
and host algal species. A clear gradient of species substitution was observed from north to south. Differences in abundance
and diversity of epifaunal crustaceans were observed between southern locations and the remaining sites. Four species were
recorded for the first time in the Portuguese coast. Among the 57 taxa identified, southern distribution limits were observed for three species and northern distribution limits were observed for
four species. Interestingly, the observed geographical patterns in epifaunal abundance and diversity were not related with
geographical changes in the indentity of the dominant algal species. 相似文献
18.
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
19.
Adriana R. Weisstaub Susana Zeni María L. de Portela Patricia A. Ronayne de Ferrer 《Journal of trace elements in medicine and biology》2006,20(1):41-47
The aim of this study was to analyze zinc (Zn), calcium (Ca) and phosphorus (P) contents in milk and the lactational performance in rats fed different Ca levels. Female Wistar rats were fed during pregnancy and lactation with experimental diets containing 20% protein and high (0.90%, HCa), normal (0.60%, NCa) or low (0.20%, LCa) Ca levels. Milk samples were collected after 15 days to determine the milk mineral composition. Pup weight was recorded from birth to weaning (litter size: 6-8 pups) to determine weight gain and calculate milk production. At delivery there were no significant differences in the body weight of the pups between the groups, but at day 15, the LCa group showed lower values than both NCa and HCa groups (p<0.05). The weight gain of the LCa group was significantly lower than of the HCa and NCa groups, between delivery and day 5 (p<0.05). This reduced rate of weight gain led to the LCa group reaching weaning weight later than the other groups. Milk production (g/pup/day) was significantly lower when dams were fed the LCa than the NCa and HCa diets (p<0.05). There were no significant differences among the groups in milk Ca, P and Zn levels and Ca/P ratio. The body mineral composition of the pups at birth did not differ between the groups; at weaning, however, both LCa and HCa groups had lower element contents than the NCa group (p<0.05). In conclusion, dams fed with a diet containing low Ca levels produced smaller volumes of milk and their pups reached weaning weights later than the other groups. As the milk mineral composition was not affected, it can be hypothesized that in dams fed low dietary Ca, the smaller milk yield might have been a way of maintaining milk quality. High Ca levels affected neither pregnancy outcome nor lactational performance. 相似文献
20.
Silvia P. Trajtemberg Nancy M. Apóstolo Graciela Fernández 《In vitro cellular & developmental biology. Plant》2006,42(6):534-537
Summary
Cynara cardunculus var. cardunculus L., also known as cardoon, is a perennial weed naturalized in the Pampas region of Argentina. A quantification of cynarine
and chlorogenic acid of callus and leaves from cardoon was performed by means of micellar electrokinetic capillary chromatography,
showing that the content of cynarine is higher in calluses than in vivo leaves. The scavenging effect of the callus extract, determined by the thiobarbituric acid method, demonstrated its significant
antioxidant capacity. The obtained results revealed that in vitro tissue culture is an excellent tool for producing cynarine for therapeutical purposes. 相似文献