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Aims The introduction of potentially invasive species through ornamental cultivation or for rehabilitation purposes is a serious environmental problem. They cause damage to biodiversity through loss, increased mortality or ' in situ ' selection phenomena in natural flora. Spartium junceum is a Mediterranean shrub that is not native in most areas of the Iberian Peninsula, although it is extensively grown for the rehabilitation of roadsides. We have investigated the effect on the native vegetation of an old S. junceum (Fabaceae) plantation in a conservation area in the centre of the Iberian Peninsula: the Cuenca Alta del Manzanares nature reserve in Madrid.Methods We compared S. junceum stands with the native nanophanerophytic Cistus ladanifer community at different ecosystem properties: soil properties, temporal soil seed bank contents, standing vegetation and net primary production of annual grasslands growing in these shrublands.Important findings The results highlighted S. junceum 's ability to become established in the new environment (marginal areas of the nature reserve) and ensure its successful growth. This is more apparent in northern and eastern exposures where this formation contacts with the core of the best conserved native vegetation in the nature reserve. Soils under Spartium showed a higher nitrogen content, indicating its capacity—in common with other legumes—to fix N, and conferring an advantage over Cistus, which is N-limited. Other soil nutrients such as phosphorus, magnesium and calcium and water availability are also higher in Spartium soils than in Cistus. Phosphorus is usually a constraint for N-fixers, but in our study, it is the most significant soil variable in both shrub formations and is important to the success of Spartium. Water availability is a key factor for Mediterranean vegetation, and particularly in autumn when soils are recharged. The Spartium formation is able to retain water as its growth produces a closer canopy than Cistus, thereby preventing water evaporation and contributing to the success of this species. Perennials are more frequent in the standing vegetation than in the seed bank, whereas therophytes are similar. The standing vegetation has therophytes and chamaephytes as the predominant growth forms in Spartium sites, and hemicryptophytes and phanerophytes in Cistus. Therophytes are dominant in Spartium and Cistus seed banks, although the first formation has more species. Spartium has a higher number of hemicryptophytes and Cistus is higher in phanerophytes. Northern and eastern aspects show significant differences in richness—with a predominance of annual weed species in Spartium —and in above-ground net primary production, probably as a consequence of the nutrients present in the soils. Ruderal annual species under Spartium (Bromus tectorum, Chenopodium album) have higher germination rates in the greenhouse than in the standing vegetation, suggesting they are at potential risk if environmental conditions change.  相似文献   
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Three species of the genus Patella were studied on the Portuguese coast as a specific contribution to the COST 647 programme. With little prior information existing, this paper presents new basic data on the geographical distribution, relative abundance, habitats, size-structure of populations, and reproductive cycles of P. depressa Pennant, 1777, P. aspera Roding, 1798, and P. vulgata L. 1758. Comparisons with N.W. Europe provide evidence of distinct latitudinal trends in the population dynamics and reproductive biology of these species.  相似文献   
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Bull breeding soundness evaluation (BBSE) usually neglects the libido and mating ability evaluation. The internal artificial vagina (IAV) permits semen sampling, as well as mating ability evaluation. Few studies have been performed using IAV with young bulls and there are none with Bos indicus bulls. The present study evaluated sexual behavior, mating ability and semen quality in young Bos taurus (Devon) and B. indicus (Nellore) bulls using the IAV device. In the first experiment, 52 Devon bulls, 18-25 months old were observed, and the behavior and mating ability recorded over a 10-min period within a restrained mount-cow with an IAV inserted. In the second experiment, 20 Nellore bulls, 20-30 months old were evaluated over a 20 min period. Of the 52 Devon bulls, 45 (86.5%) had semen recovered with the IAV, 31 (69.0%) were considered satisfactory. Nellore bulls exhibited a different sexual behavior, with 10 bulls not showing any interest in the females. Four bulls demonstrated sexual interest only once, e.g., sniffing, two showed interest on more than one occasion, and four had more than two mounts or mounting attempts. None out of the Nellore bulls was collected with IAV. The IAV was an effective and welfare-promoting animal technology for the evaluation of semen quality and mating ability of B. taurus bulls. However, the IAV was not adequate for young Nellore bulls, probably due to their quiescent sexual behavior and delayed sexual maturity. Further studies are needed to evaluate the performance of the IAV for older Nellore bulls.  相似文献   
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Objectives:evaluate the effects that whole-body vibration (WBV) causes on the neuromuscular junctions and oxidative stress of the soleus muscle of obese Wistar rats.Methods:32 male Wistar rats were used, 16 of which were obesity induced by monosodium glutamate, randomized into four groups: control (GC), control with WBV (GCP), obese (GO) and obese with WBV (GOP). At the 70 days old, the training on WBV was started, performed 3 times a week, during 8 consecutive weeks. At the 130 days old, the animals were euthanized and the soleus muscles were collected.Results:Regarding the analysis of the neuromuscular junctions, the obese groups had lower mean size when compared to the control groups. On the other hand, the WBV presented higher averages when compared to the groups that did not perform the training. Regarding the oxidative stress, for the lipid peroxidation there was a significant difference between obese and non-obese animals, however, there was no difference between the animals WBV and those who did not.Conclusion:WBV promotes beneficial changes such as increased measurements of the structures of the neuromuscular junctions, but is not able to promote changes in the concentration of the cholinesterase enzyme in the synaptic cleft.  相似文献   
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