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排序方式: 共有552条查询结果,搜索用时 31 毫秒
171.
Mattia Martin Azzella Mauro Iberite Simonetta Fascetti Leonardo Rosati 《Plant biosystems》2013,147(2):521-524
Italian volcanic lakes represent an important hotspot of aquatic plant diversity. By comparing original data collected in 2009/10 with historical data, we detected species extinction and loss of habitats 3140 and 3150 (Habitats Directive 92/43/EEC). The speed of change detected claim for frequent monitoring and rapid management interventions. 相似文献
172.
Abstract Two new italian stations of Jonopsidium savianum (Caruel) Ball ex Arc. – The authors point out the presence of Jonopsidium savianum (Caruel) Ball ex Arc. in two stations in the mount la Pelosa (Central Apennines). These new stations are characterized by a different climate as regards of those already well-known of mount Calvi, mount Pelato and mount Carvoli in Tuscany. This italian endemism, till now limited to the western Tuscan, had very probably an area of distribution in Central Italy more videly extended than nowadays, but the climatic changes of the post-glacial period may have caused its reduction and the isolation of this species only in very little stations. 相似文献
173.
Mattia Pasqua Ulysse Pereira Claire de Lartigue Jonathan Nicolas Pascale Vigneron Quentin Dermigny Ccile Legallais 《Biotechnology and bioengineering》2021,118(1):453-464
We recently demonstrated that HepaRG cells encapsulated into 1.5% alginate beads are capable of self‐assembling into spheroids. They adequately differentiate into hepatocyte‐like cells, with hepatic features observed at Day 14 post‐encapsulation required for external bioartificial liver applications. Preliminary investigations performed within a bioreactor under shear stress conditions and using a culture medium mimicking acute liver failure (ALF) highlighted the need to reinforce beads with a polymer coating. We demonstrated in a first step that a poly‐l ‐lysine coating improved the mechanical stability, without altering the metabolic activities necessary for bioartificial liver applications (such as ammonia and lactate elimination). In a second step, we tested the optimized biomass in a newly designed perfused dynamic bioreactor, in the presence of the medium model for pathological plasma for 6 h. Performances of the biomass were enhanced as compared to the steady configuration, demonstrating its efficacy in decreasing the typical toxins of ALF. This type of bioreactor is easy to scale up as it relies on the number of micro‐encapsulated cells, and could provide an adequate hepatic biomass for liver supply. Its design allows it to be integrated into a hybrid artificial/bioartificial liver setup for further clinical studies regarding its impact on ALF animal models. 相似文献
174.
Mattia Saccò Nicole E. White Chris Harrod Gonzalo Salazar Pablo Aguilar Carolina F. Cubillos Karina Meredith Bonnie K. Baxter Aharon Oren Elena Anufriieva Nickolai Shadrin Yeri Marambio-Alfaro Víctor Bravo-Naranjo Morten E. Allentoft 《Biological reviews of the Cambridge Philosophical Society》2021,96(6):2828-2850
When it comes to the investigation of key ecosystems in the world, we often omit salt from the ecological recipe. In fact, despite occupying almost half of the volume of inland waters and providing crucial services to humanity and nature, inland saline ecosystems are often overlooked in discussions regarding the preservation of global aquatic resources of our planet. As a result, our knowledge of the biological and geochemical dynamics shaping these environments remains incomplete and we are hesitant in framing effective protective strategies against the increasing natural and anthropogenic threats faced by such habitats. Hypersaline lakes, water bodies where the concentration of salt exceeds 35 g/l, occur mainly in arid and semiarid areas resulting from hydrological imbalances triggering the accumulation of salts over time. Often considered the ‘exotic siblings’ within the family of inland waters, these ecosystems host some of the most extremophile communities worldwide and provide essential habitats for waterbirds and many other organisms in already water-stressed regions. These systems are often highlighted as natural laboratories, ideal for addressing central ecological questions due to their relatively low complexity and simple food web structures. However, recent studies on the biogeochemical mechanisms framing hypersaline communities have challenged this archetype, arguing that newly discovered highly diverse communities are characterised by specific trophic interactions shaped by high levels of specialisation. The main goal of this review is to explore our current understanding of the ecological dynamics of hypersaline ecosystems by addressing four main research questions: (i) why are hypersaline lakes unique from a biological and geochemical perspective; (ii) which biota inhabit these ecosystems and how have they adapted to the high salt conditions; (iii) how do we protect biodiversity from increasing natural and anthropogenic threats; and (iv) which scientific tools will help us preserve hypersaline ecosystems in the future? First, we focus on the ecological characterisation of hypersaline ecosystems, illustrate hydrogeochemical dynamics regulating such environments, and outline key ecoregions supporting hypersaline systems across the globe. Second, we depict the diversity and functional aspects of key taxa found in hypersaline lakes, from microorganisms to plants, invertebrates, waterbirds and upper trophic levels. Next, we describe ecosystem services and discuss possible conservation guidelines. Finally, we outline how cutting-edge technologies can provide new insights into the study of hypersaline ecology. Overall, this review sheds further light onto these understudied ecosystems, largely unrecognised as important sources of unique biological and functional diversity. We provide perspectives for key future research avenues, and advocate that the conservation of hypersaline lakes should not be taken with ‘a grain of salt’. 相似文献
175.
Barberis Marta Bogo Gherardo Bortolotti Laura Conte Lucia Alessandrini Mattia Nepi Massimo Galloni Marta 《Plant Ecology》2021,222(2):233-246
Plant Ecology - Floral nectar is a chemically complex aqueous solution within which several secondary metabolites have been identified that affect attractiveness for pollinators. Understanding... 相似文献
176.
The aim of this study was to evaluate the interfacial behavior of syringic acid, tyrosol and oleuropein, phenolic antioxidant
compounds naturally present in olives and olive oils, and their ability to influence the stability to lipid oxidation of olive
oil O/W emulsions. To test also the interactions of these molecules with other components and the effects on their activity,
two different surfactants were used to prepare the olive oil emulsions, Tween 20, and a whey protein concentrate (WPC). All
the antioxidants affected the olive oil/water interfacial tension; among them, oleuropein showed the highest interfacial activity
and, thus, is supposed to locate at the interface. In emulsified state, the presence of the phenolic compounds in WPC emulsions
did not cause any significant effect on the dispersion degree if compared to the control whilst a general improvement was
observed in Tween 20-emulsions, in particular when oleuropein was added systems. The antioxidants were thus proven not to
impair the dispersed structure but rather to improve it. As regards the oxidative stability, the antioxidants under investigation
caused the occurrence of similar induction phases in the hydroperoxides production not observed in the control emulsions.
In the case of secondary oxidation products, the highest inhibition was achieved in both the emulsified systems by oleuropein.
In general, however, a lower amount of both primary and secondary oxidation products were observed in WPC emulsions than in
Tween 20-emulsions likely due to the antioxidative effect of whey proteins. 相似文献
177.
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179.
Capsule Key marginal habitat features maintain their importance even when they occur at very low density. Aims To assess the importance for breeding birds of key habitat elements, such as isolated shrubs, hedgerows and untilled vegetation patches. Methods We investigated the habitat preferences of Red-backed Shrikes Lanius collurio in an agricultural environment where key habitat elements have been dramatically reduced. Based upon data from territorial maps, a fine-scale model of habitat preference was developed and the results of three different analytical approaches (binary logistic regression, multimodel inference and hierarchical partitioning) were compared. Results The occurrence of Red-backed Shrikes was positively influenced by the extent of non-grazed/mown grassland, isolated bushes and hedgerows, and negatively influenced by woodland cover. The model highlighted the importance of bushes/hedgerows despite their very scarce occurrence in the study areas (overall, average cover only 7.94%). Breeding densities were rather low, but mean densities were slightly higher in pasture zones in which bushes/hedgerows availability was higher than elsewhere. Conclusion These results confirm the crucial importance of these key marginal elements even in depauperated farmland landscapes. Maintaining and increasing their availability is a key management option for the encouragement of breeding Red-backed Shrikes, and potentially for other species which are also declining in these farmland habitats. 相似文献
180.
Capsule We analysed habitat preferences of Black-eared Wheatear Oenanthe hispanica of the eastern subspecies (O. hispanica melanoleuca) in South Italy, considering 1-ha (coinciding with territory size) square plots (49 occupied and 49 unoccupied). We used multi-adaptive regression splines to model habitat preferences. Black-eared Wheatear occurrence was positively associated with three factors: aspect (a SE orientation was preferred), cover of grazed grassland and cover of bare ground. Species conservation should be based on the maintenance of grazed grasslands, especially on SE-facing slopes, and including at least 2500 m2 of bare ground per ha. 相似文献