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111.
Heteropteran legs are very diverse within and among taxa, and such variation is frequently correlated with life habits. Structural modifications are commonly present in the legs of the Pentatomoidea but are poorly studied. Using scanning electron microscopy, the tibia and pretarsal microstructure of 82 species of Pentatomidae (Heteroptera), three species of Scutelleridae, and ten species of Thyreocoridae were described, focusing on the pretarsal structure, the foretibial apparatus, and the foretibial comb. The Pentatomidae, the Scutelleridae, and the Thyreocoridae have uniform pretarsal structures. Variation can be found in the length of the parempodial setae and in the shape of the parempodial projections. The foretibial combs of the Pentatomidae, the Thyreocoridae, and the Scutelleridae are described for the first time, and we have demonstrated that there is low structural variation in the foretibial comb complex of the studied species. The setae organization and distribution on the foretibial apparatus is uniform in the families studied. However, the Asopinae (Pentatomidae) bear a foretibial apparatus that is uniquely organized. The taxonomic and phylogenetic relevance of the pretarsal traits, the foretibial apparatus, and the foretibial comb are discussed. 相似文献
112.
Mathias Ahii Chia Ana Teresa Lombardi Maria da Graça Gama Melão 《Phycological Research》2013,61(4):286-291
Quantification of the calorific content of microalgae is critical in studies of energy flow, trophic partitioning, plant/herbivore interactions in aquaculture and biomass production for biofuels. We investigated the calorific value and biochemical composition of Chlorella vulgaris at different phosphorus (P) concentrations (6.0 × 10?7, 2.3 × 10?6 and 2.3 × 10?4 mol L?1 P). As expected, the control (2.3 × 10?4 mol L?1 P) supported better growth than P limited treatments. Biomolecules like total carbohydrates and lipids accumulated under P limitation, which significantly correlated with high calorific values. Lipid class composition showed that triacylglycerols were the most accumulated under P limited conditions. The calorific value reported under control conditions (13.78 kJ g?1) was less than those obtained under P limitation (30.47–33.07 kJ g?1). The highest calorific value with less growth retardation was obtained at 2.3 × 10?6 mol L?1 P. 相似文献
113.
João de Pina‐Cabral 《The journal of the Royal Anthropological Institute》2013,19(1):75-101
This article is a study of personal naming using drawings made by secondary school students from two small towns in coastal Bahia (Brazil) of the persons who gave them their names. The article explores the relation between namer and named as one of continued identity created by imaginative processes of surrogation akin to pretend‐play. In early ontogeny, the person is constituted through a series of mutualities of being that come to constitute a core of affects. The article aims to contribute towards a better understanding of the processes of constitution of personhood in the context of human relatedness. 相似文献
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Jaciane Lutz Ienczak Willibaldo Schmidell Gláucia Maria Falcão de Aragão 《Journal of industrial microbiology & biotechnology》2013,40(3-4):275-286
This article gives an overview of high-cell-density cultures for polyhydroxyalkanoate (PHA) production and their modes of operation for increasing productivity. High cell densities are very important in PHA production mainly because this polymer is an intracellular product accumulated in various microorganisms, so a high cellular content is needed for the polymer production. This review describes relevant results from fed-batch, repeated batch, and continuous modes of operation without and with cell recycle for the production of these polymers by microorganisms. Finally, recombinant microorganisms for PHA production, as well future directions for PHA production, are discussed. 相似文献
116.
Sílvia Castro Victoria Ferrero Joana Costa Ana João Sousa Mariana Castro Luis Navarro João Loureiro 《Biological invasions》2013,15(8):1863-1875
Oxalis pes-caprae, a tristylous flowering plant native to South Africa, is described in the western Mediterranean basin as an asexual—only 5x short-styled morph (5x S-morph) invasive weed losing all mating partners after introduction. The objective of this study was to reassess the patterns of floral morph and cytotype distribution and the sexual reproduction ability in this invaded range. For that, floral morph and cytotype composition were evaluated in 39 populations of O. pes-caprae in a methodical sampling. The reproductive success of natural populations was assessed as fruit and seed production and seed germination for all floral morphs and cytotypes detected. Self- and morph-incompatibility were also studied with controlled hand pollinations. A remarkable diversity in floral morph and cytotype composition was observed. Furthermore, we observed successful sexual reproduction in several localities across the surveyed area. The S-morph is still dominant in this invaded area, and although it was mostly 5x, an additional cytotype (4x) was also recorded. Records of both a mid-styled morph (M-morph) and an area with trimorphic populations of this species are reported here for the first time in the invasive range of the Mediterranean basin. The long-styled morph appears to occur randomly across the surveyed area, while the M-morph is concentrated mainly in Estremadura province (Portugal), where a breakdown in the incompatibility system was observed. These distribution patterns may result from events of sexual reproduction after incompatibility breakdown and/or from multiple introduction events from the native area. The ability to reproduce sexually, undetected so far, may have important impacts in the population dynamics and major consequences for the adaptation and selection potential of O. pes-caprae in this invaded area. 相似文献
117.
Victoria Ferrero Sílvia Castro Joana Costa Paola Acuña Luis Navarro João Loureiro 《Biological invasions》2013,15(10):2347-2358
Removal of invasive species often benefits biological diversity allowing ecosystems’ recovery. However, it is important to assess the functional roles that invaders may have established in their new areas to avoid unexpected results from species elimination. Invasive animal-pollinated plants may affect the plant–pollination interactions by changing pollinator availability and/or behaviour in the community. Thus, removal of an invasive plant may have important effects on pollinator community that may then be reflected positive or negatively on the reproductive success of native plants. The objective of this study was to assess the effect of removing Oxalis pes-caprae, an invasive weed widely spread in the Mediterranean basin, on plant–pollinator interactions and on the reproductive success of co-flowering native plants. For this, a disturbed area in central Portugal, where this species is highly abundant, was selected. Visitation rates, natural pollen loads, pollen tube growth and natural fruit set of native plants were compared in the presence of O. pes-caprae and after manual removal of their flowers. Our results showed a highly resilient pollination network but also revealed some facilitative effects of O. pes-caprae on the reproductive success of co-flowering native plants. Reproductive success of the native plants seems to depend not only on the number and diversity of floral visitors, but also on their efficiency as pollinators. The information provided on the effects of invasive species on the sexual reproductive success of natives is essential for adequate management of invaded areas. 相似文献
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