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991.
Temporal patterns in Saturnidae (silk moth) and Sphingidae (hawk moth) assemblages in protected forests of central Uganda
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Perpetra Akite Richard J. Telford Paul Waring Anne M. Akol Vigdis Vandvik 《Ecology and evolution》2015,5(8):1746-1757
Forest‐dependent biodiversity is threatened throughout the tropics by habitat loss and land‐use intensification of the matrix habitats. We resampled historic data on two moth families, known to play central roles in many ecosystem processes, to evaluate temporal changes in species richness and community structure in three protected forests in central Uganda in a rapidly changing matrix. Our results show some significant declines in the moth species richness and the relative abundance and richness of forest‐dependent species over the last 20–40 years. The observed changes in species richness and composition among different forests, ecological types, and moth groups highlight the need to repeatedly monitor biodiversity even within protected and relatively intact forests. 相似文献
992.
Shared patterns of species turnover between seaweeds and seed plants break down at increasing distances from the sea
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Carlos F. D. Gurgel Thomas Wernberg Mads S. Thomsen Bayden D. Russell Paul Adam Jonathan M. Waters Sean D. Connell 《Ecology and evolution》2014,4(1):27-34
We tested for correlations in the degree of spatial similarity between algal and terrestrial plants communities along 5500 km of temperate Australian coastline and whether the strength of correlation weakens with increasing distance from the coast. We identified strong correlations between macroalgal and terrestrial plant communities within the first 100 km from shore, where the strength of these marine–terrestrial correlations indeed weakens with increasing distance inland. As such, our results suggest that marine‐driven community homogenization processes decompose with increasing distance from the shore toward inland. We speculate that the proximity to the marine environment produces lower levels of community turnover on land, and this effect decreases progressively farther inland. Our analysis suggests underlying ecological and evolutionary processes that give rise to continental‐scale biogeographic influence from sea to land. 相似文献
993.
Puchart V Vrsanská M Mastihubová M Topakas E Vafiadi C Faulds CB Tenkanen M Christakopoulos P Biely P 《Journal of biotechnology》2007,127(2):235-243
4-Nitrophenyl glycosides of 2-, 3-, and 5-O-(E)-feruloyl- and 2- and 5-O-acetyl-alpha-L-arabinofuranosides and of 2-, 3-, and 4-O-(E)-feruloyl- and 2-, 3- and 4-O-acetyl-beta-D-xylopyranosides, compounds mimicking natural substrates, were used to investigate substrate and positional specificity of type-A, -B, and -C feruloyl esterases. All the feruloyl esterases behave as true feruloyl esterases showing negligible activity on sugar acetates. Type-A enzymes, represented by AnFaeA from Aspergillus niger and FoFaeII from Fusarium oxysporum, are specialized for deferuloylation of primary hydroxyl groups, with a very strong preference for hydrolyzing 5-O-feruloyl-alpha-L-arabinofuranoside. On the contrary, type-B and -C feruloyl esterases, represented by FoFaeI from F. oxysporum and TsFaeC from Talaromyces stipitatus, acted on almost all ferulates with exception of 4- and 3-O-feruloyl-beta-D-xylopyranoside. 5-O-Feruloyl-alpha-L-arabinofuranoside was the best substrate for both TsFaeC and FoFaeI, although catalytic efficiency of the latter enzyme toward 2-O-feruloyl-alpha-L-arabinofuranoside was comparable. In comparison with acetates, the corresponding ferulates served as poor substrates for the carbohydrate esterase family 1 feruloyl esterase from Aspergillus oryzae. The enzyme hydrolyzed all alpha-L-arabinofuranoside and beta-D-xylopyranoside acetates. It behaved as a non-specific acetyl esterase rather than a feruloyl esterase, with a preference for 2-O-acetyl-beta-D-xylopyranoside. 相似文献
994.
We present a model of tunnel excavation by termites that requires no pheromone labeling of soil or work sites, but instead
relies on tactile interactions and individuals who actively orient their movement. Potential termite excavators moved from
the tunnel origin towards the distal end of the tunnel and formed a queue behind those termites at the digging face. Delayed
termites excavated soil laterally from the tunnel wall at a position governed by their position in the queue of termites.
By examining excavation under artificially induced conditions of longer and shorter queues of termites at the tunnel end,
we showed that tunnel width increased with increased queue size and the rate of lateral excavation in a process we termed
“digging pressure.” 相似文献
995.
William G. Ambrose Jr. Paul E. Renaud William L. Locke V Finlo R. Cottier J?rgen Berge Michael L. Carroll Benjamin Levin Stuart Ryan 《Polar Biology》2012,35(3):345-354
Growth patterns of two common circumpolar bivalves, the Greenland cockle (Serripes groenlandicus), and the hairy cockle (Clinocardium ciliatum) have been used in previous studies to reconstruct environmental conditions in the arctic. To date, there has been no direct
determination that growth lines in either species are deposited periodically, and there has been no examination of factors
affecting growth. We placed calcein-marked individuals of both species on oceanographic moorings in two fjords (Rijpfjord
and Kongsfjord) in the Svalbard archipelago for one and two (Kongsfjord only) years. Growth patterns were compared with concurrent
in situ temperature and fluorescence data in order to assess environmental controls on growth. Dark growth lines are evident
on the outer shell surface and internally in shell cross section in both S. groenlandicus and C. ciliatum, and both species deposited only one line per year, unequivocally confirming that internal lines are deposited annually. Growth
line deposition in both species began in late summer to early fall, before the seasonal decline in temperature. There was
no difference in growth of S. groenlandicus between the two fjords despite differences in water temperature (3°C), fluorescence (nearly threefold) and the onset and
duration of the winter season. C. ciliatum, however, grew approximately 2.8 times faster in the warmer, more food-rich Kongsfjord than in Rijpfjord. Subannual lines
were counted in two individuals of each species from each fjord, but deposition of these lines was not clearly related to
number of growing days estimated by temperature and fluorescence. 相似文献
996.
997.
998.
Jack A. Grebb Jean-Antoine Girault† Michelle Ehrlich‡ Paul Greengard 《Journal of neurochemistry》1990,55(1):204-207
DARPP-32 (dopamine- and cyclic AMP-regulated phosphoprotein, Mr = 32,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) is a neuronal phosphoprotein that is enriched in neurons which possess dopamine D1 receptors, particularly striatonigral neurons. In rat brain slices, the phosphorylation state of DARPP-32 is regulated by dopamine, acting through the dopamine D1 receptor and the adenylyl cyclase system. This study reports that chronic blockade (21 days) of either dopamine D1 receptors by SCH-23390 or dopamine D2 receptors by raclopride does not affect the concentrations of DARPP-32 in specific rat brain regions (striatum, thalamus, hippocampus, frontal cerebral cortical pole). Northern blot analysis indicates that the steady-state level of DARPP-32 mRNA in striatum is also unchanged by these treatments. 相似文献
999.
Vitaly A Selivanov Pedro Vizán Faustino Mollinedo Teresa WM Fan Paul WN Lee Marta Cascante 《BMC systems biology》2010,4(1):135