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Preservation of a good ecological status in riverine habitats emerged as a priority for water management policies in Europe since the negative impact caused by the construction and operation of dams on the ecohydrology and habitat availability became more evident. Ecological flows, as reported in the recently published European guidance, represent a link between water and habitat EU Directives. This study presents the application of a mesohabitat simulation model (MesoHABSIM) to evaluate and quantify ecological flows in a highly regulated Mediterranean watershed (Nestos River, Northern Greece). Data collection was performed through GIS/GPS mapping surveys, hydro-morphological measurements (water depth, flow, substratum type, etc.) and electrofishing samplings at mesohabitat scale under different discharge conditions. In total, 81 hydro-morphological units were surveyed and 7532 fish samples were collected to develop habitat suitability predictions. Ecological flows were calculated in the range 10–15 m3/s as the required discharge which assures the welfare and sustainability of protected fish species populations. In the lower course of the Nestos River habitat time-series indicated irrigation abstractions as a major stressor since summer was the period where habitat availability thresholds were mostly violated. Application of a revised water management plan is required for the downstream part of the Nestos River in order to maintain high ecological standards in the Natura 2000 sites of the Delta. [ABSTRACT FROM AUTHOR]

Background: Fumaria capreolata L. (Papaveraceae) is a botanical drug used in North Africa for its gastro-intestinal and anti-inflammatory properties. It is characterized for the presence of several alkaloids that could be responsible for some of its effects, including an immunomodulatory activity.Purpose: To test in vivo the intestinal anti-inflammatory properties of the total alkaloid fraction extracted from the aerial parts of F. capreolata (AFC), and to evaluate its effects on an intestinal epithelial cell line.Study Design and Methods: AFC was chemically characterized by liquid chromatography coupled to diode array detection and high resolution mass spectrometry. Different doses of AFC (25, 50 and 100mg/kg) were assayed in the DNBS model of experimental colitis in mice, and the colonic damage was evaluated both histologically and biochemically. In addition, in vitro experiments were performed with this alkaloid fraction on the mouse intestinal epithelial cell line CMT93 stimulated with LPS.Results: The chemical analysis of AFC revealed the presence of 23 alkaloids, being the most abundants stylopine, protopine and coptisine. Oral administration of AFC produced a significant inhibition of the release and the expression of IL-6 and TNF-α in the colonic tissue. It also suppressed in vivo the transcription of other pro-inflammatory mediators such as IL-1β, iNOS, IL-12 and IL-17. Furthermore, AFC showed an immunomodulatory effect in vitro since it was able to inhibit the mRNA expression of IL-6, TNF-α and ICAM-1. Moreover, the beneficial effect of AFC in the colitic mice could also be associated with the normalization of the expression of MUC-2 and ZO-1, which are important for the intestinal epithelial integrity.Conclusion: The present study suggests that AFC, containing 1.3% of stylopine and 0.9% of protopine, significantly exerted intestinal anti-inflammatory effects in an experimental model of mouse colitis. This fact could be related to a modulation of the intestinal immune response and a restoration of the intestinal epithelial function. [ABSTRACT FROM AUTHOR]

The invasion of freshwater ecosystems is a particularly alarming phenomenon in the Iberian Peninsula. Habitat suitability modelling is a proficient approach to extract knowledge about species ecology and to guide adequate management actions. Decision-trees are an interpretable modelling technique widely used in ecology, able to handle strongly nonlinear relationships with high order interactions and diverse variable types. Decision-trees recursively split the input space into two parts maximising child node homogeneity. This recursive partitioning is typically performed with axis-parallel splits in a top-down fashion. However, recent developments of the R packages oblique.tree , which allows the development of oblique split-based decision-trees, and evtree , which performs globally optimal searches with evolutionary algorithms to do so, seem to outperform the standard axis-parallel top-down algorithms; CART and C5.0. To evaluate their possible use in ecology, the two new partitioning algorithms were compared with the two well-known, standard axis-parallel algorithms. The entire process was performed in R by simultaneously tuning the decision-tree parameters and the variables subset with a genetic algorithm and modelling the presence–absence of the Iberian gudgeon ( Gobio lozanoi ; Doadrio and Madeira, 2004), an invasive fish species that has spread across the Iberian Peninsula. The accuracy and complexity of the trees, the modelled patterns of mesohabitat selection and the variables importance were compared. None of the new R packages, namely oblique.tree and evtree , outperformed the C5.0 algorithm. They rendered almost the same decision-trees as the CART algorithm, although they were completely interpretable – they performed from four to eight partitions – in comparison with C5.0, which resulted in a more complex structure with 17 partitions. Oblique.tree proved to be affected by prevalence and it does not include the possibility of weighting the observations, which potentially discourage its actual use. Although the use of evtree did not suggest a major improvement compared with the remaining packages, it allowed the development of regression trees which may be informative for additional modelling tasks such as abundance estimation. Looking at the resulting decision-trees, the optimal habitats for the Iberian gudgeon were large pools in lowland river segments with depositional areas and aquatic vegetation present, which typically appeared in the form of scattered macrophytes clumps. Furthermore, Iberian gudgeon seems to avoid habitats characterised by scouring phenomena and limited vegetated cover availability. Accordingly, we can assume that river regulation and artificial impoundment would have favoured the spread of the Iberian gudgeon across the entire peninsula. [ABSTRACT FROM AUTHOR]

Phenolic compounds in extracts of three olive leaf cultivars were determined using HPLC-DAD-TOF-MS. The determination of the immunomodulatory properties of the whole phenolic extracts was then carried out on RAW 264 mouse macrophages as a preliminary in vitro study. Twenty-eight phenolic compounds were determined in the olive leaf extracts and high contents of total phenolics were shown, particularly for ‘Picual’ cultivar. In addition, all olive leaf extracts inhibited the release of the pro-inflammatory mediator nitric oxide in LPS-stimulated RAW264.7 cells revealing their immunomodulatory properties. As a preliminary result, it could be deduced that the inhibition of NO by the olive leaf extract may depend on the type of phenolic compounds rather than on the total phenolic contents. This is the first time that whole phenolic extracts of olive leaves have been used in in vitro study of their anti-inflammatory properties. [ABSTRACT FROM AUTHOR]

Previous research indicated that high predictive performance in species distribution modelling can be obtained by combining both biotic and abiotic habitat variables. However, models developed for fish often only address physical habitat characteristics, thus omitting potentially important biotic factors. Therefore, we assessed the impact of biotic variables on fish habitat preferences in four selected stretches of the upper Cabriel River (E Spain). The occurrence of Squalius pyrenaicus and Luciobarbus guiraonis was related to environmental variables describing biotic interactions (inferred by relationships among fish abundances) and channel hydro-morphological characteristics. Random Forests (RF) models were trained and then validated using independent datasets. To build RF models, the conditional variable importance was used together with the model improvement ratio technique. The procedure showed effectiveness in identifying a parsimonious set of not correlated variables, which minimize noise and improve model performance in both training and validation phases. Water depth, channel width, fine substrate and water-surface gradient were selected as most important habitat variables for both fish. Results showed clear habitat overlapping between fish species and suggest that competition is not a strong factor in the study area. [ABSTRACT FROM AUTHOR]