Co‐viability of a Mediterranean demersal fishery affected by the discard ban under alternative management scenarios

The joint viability, or co‐viability, of a Mediterranean Sea mixed demersal fishery was examined by applying a bioeconomic fisheries model to the main seven target stocks of the fishery under biological, social and economic constraints. The stocks of interest were hake, black‐bellied angler, deep‐water rose shrimp, red mullet, blue and red shrimp, Norway lobster and blue whiting, all of which were assessed as overexploited. Their combined production corresponds to 34% by volume and 52% by value of the landings of the demersal fishery studied. Simulation scenarios based on effort reduction, changes in the selectivity pattern and implementing a fisheries restricted area were compared over the simulation horizon of 2015–2030. The latter two scenarios were also examined in terms of full or partial compliance. The effect of a discard ban on the economy of the fleet was also analysed. The results show that the fishery is not co‐viable because some stocks are not viable in the projection period, but social and economic viability was ensured in all cases. As is often the case for mixed fisheries, a unique management measure is unlikely to improve the situation of all stocks simultaneously, but all the management measures tested are better than the status quo.     

Captive breeding of Margaritifera auricularia (Spengler, 1793) and its conservation importance

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Presence of Pharmaceuticals and Hormones in Waters from Sewage Treatment Plants

This paper describes the presence of 33 pharmaceuticals and hormones in waters from two sewage treatment plants (STPs) situated in Catalonia, in northeastern Spain. The target compounds were one psychoactive stimulant, one antiepileptic, four analgesics and non-steroidal anti-inflammatories, one lipid regulators, two anti-ulcer agents, nine antibiotics (sulfonamides and macrolides), two beta-blockers, two metabolites, and 11 hormones (free and conjugates). The determination was performed using liquid chromatography coupled to tandem mass spectrometry after enrichment by solid-phase extraction with Oasis HLB sorbent. Most of the pharmaceuticals were found in both influent and effluent samples from the two STPs. The most frequently detected were caffeine, acetaminophen, carbamazepine, diclofenac, ibuprofen, naproxen, sulfamethoxazole, sulfapyridine, sulfathiazole, ranitidine, omeprazole, estrone 3-sulfate, and estradiol 17-glucuronide. Specifically, the highest concentrations found in influents were 19,850?ng/L (acetaminophen), 9,945?ng/L (caffeine), 4,215?ng/L (ibuprofen), 5,695?ng/L (sulfamethoxazole), and 5,140?ng/L (sulfathiazole). Most of the pharmaceuticals present in influent waters were found in effluents at lower concentrations. The highest concentrations in effluents were 970?ng/L (caffeine), 670?ng/L (sulfamethoxazole), 510?ng/L (bezafibrate), and 1,032?ng/L (diclofenac).     

Characterization of the Salinisation Processes in Aquifers Using Boron Isotopes; Application to South-Eastern Spain

Use of δ¹¹B provides a solid tool for discriminating hydrogeochemical processes in complex coastal aquifers. Its efficiency increases markedly when it is applied along with other major or minor constituents. Nevertheless, various factors may affect its interpretation: the presence of clays, which favour adsorption and desorption, the influence of wastewaters, and even the presence of geothermalism. The δ¹¹B has been applied to the study of a series of aquifers in south-eastern Spain: Castell de Ferro (Granada), Campo de Dalías, Lower Andarax and Sorbas (Almería), all of which are complex and heterogeneous. The results obtained demonstrate that the concentration of Br, the SO₄/Cl and Cl/Br ratios are good indicators of marine intrusion. Inland some negative values of δ¹¹B (?16.7 and ?8.1‰) are related to a geothermal influence (34.8 and 51.5°C). The boron solubility is directly related to temperature favours boron mobilization, even from the associated metapelitic deposits. The difference in the boron isotope content in two carbonate units must be caused by the different composition of the carbonate rocks, as well as a long residence time.     

Regolith behaviour and physical weathering of clayey mudrock as dependent on seasonal weather conditions in a badland area at Vallcebre, Eastern Pyrenees

Studies on badland areas in the Vallcebre basin (Pyrenees) suggest that erosion rates are controlled by the weathering rate of mudrocks. To obtain the temporal pattern of physical weathering and its control on the erosive processes, monitoring of regolith temperatures at different aspect, depth and lithology, and periodical determination of regolith moisture and bulk density were carried out. Changes in surface regolith have also been monitored by means of photographic techniques, using an especially designed tripod. Finally, the hydrological and erosive response of the regolith trough the seasons were studied using rainfall simulations. The results obtained support and confirm previous knowledge on the role of frost action in mudrock weathering and the role of subsequent regolith development and wetness status on infiltration and runoff generation. These seasonal changes of behaviour are so important that they raise serious questions about the validity of observations or experiments carried out in only one season.This work confirms that erosion processes are controlled by regolith formation during winter and regolith depletion by storm rainfall erosion during summer, spring and early autumn. It also raises important points about annual trends of infiltration and erodibility, that should be used as guidelines for modelling runoff and sediment production.     

Incidental catch of marine turtles by Spanish bottom trawlers in the western Mediterranean

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Experimental infection with H1N1 European swine influenza virus protects pigs from an infection with the 2009 pandemic H1N1 human influenza virus

The recent pandemic caused by human influenza virus A(H1N1) 2009 contains ancestral gene segments from North American and Eurasian swine lineages as well as from avian and human influenza lineages. The emergence of this A(H1N1) 2009 poses a potential global threat for human health and the fact that it can infect other species, like pigs, favours a possible encounter with other influenza viruses circulating in swine herds. In Europe, H1N1, H1N2 and H3N2 subtypes of swine influenza virus currently have a high prevalence in commercial farms. To better assess the risk posed by the A(H1N1) 2009 in the actual situation of swine farms, we sought to analyze whether a previous infection with a circulating European avian-like swine A/Swine/Spain/53207/2004 (H1N1) influenza virus (hereafter referred to as SwH1N1) generated or not cross-protective immunity against a subsequent infection with the new human pandemic A/Catalonia/63/2009 (H1N1) influenza virus (hereafter referred to as pH1N1) 21 days apart. Pigs infected only with pH1N1 had mild to moderate pathological findings, consisting on broncho-interstitial pneumonia. However, pigs inoculated with SwH1N1 virus and subsequently infected with pH1N1 had very mild lung lesions, apparently attributed to the remaining lesions caused by SwH1N1 infection. These later pigs also exhibited boosted levels of specific antibodies. Finally, animals firstly infected with SwH1N1 virus and latter infected with pH1N1 exhibited undetectable viral RNA load in nasal swabs and lungs after challenge with pH1N1, indicating a cross-protective effect between both strains.     

Flagellar Sensillar Equipment of Two Morphologically Closely Related Aphid Hyperparasitoids (Hymenoptera: Figitidae: Alloxysta)

The antennal sensillar equipment in the parasitic wasp family Figitidae was analyzed to date only in few species, despite some are associated with crop pests and can have an economic importance. It is the case of the genus Alloxysta, which includes hyperparasitoids of aphids which can potentially reduce effectiveness of primary pest parasitoids. Here we analyzed, through scanning electron microscopy, the diversity, morphology, and distribution of the antennal sensilla in males and females of Alloxysta consobrina (Zetterstedt) and Alloxysta victrix (Westwood), two species with overall very similar morphology. In both species, antennae are filiform and cylindrical, and flagellum was longer in A. victrix. Eight sensillar types have been recognized: four types of sensilla trichoidea (ST-A, ST-B, ST-C, ST-D), sensilla coeloconica, sensilla placoidea, sensilla campaniformia, and sensilla basiconica. ST-A, ST-B, ST-C, and sensilla placoidea were the most abundant types on the antennae and often increased in number and decreased in size toward the tip of antenna. The two species seem to have several differences in their sensillar equipment, possibly in accordance with the different degree of host range. On the other hand, sexual dimorphism is probably due to the different stimuli that have to be correctly processed. The comparison with the other species of Figitidae studied by far showed, at subfamily-level, that variability in sensillar equipment and phylogeny do not agree. This suggests a complex series of morphological changes during evolution of this group. The taxonomic sample should be thus substantially enlarged to disclose possible trends in sensillar equipment evolution in the family.     

Taming Winfree turbulence of scroll waves in excitable media

Winfree turbulence of scroll waves is a special kind of spatiotemporal chaos that exists exclusively in three-dimensional excitable media and is currently considered one of the principal mechanisms of cardiac fibrillation. A chaotic wave pattern develops through the negative-tension instability of vortex filaments, which tend to spontaneously stretch, bend, loop, and produce an expanding tangle that fills up the volume. We demonstrate that such turbulence can readily be controlled by weak nonresonant modulation of the medium excitability. Depending on the forcing frequency, either suppression or induction of turbulence can be achieved.     

Application of sex reversal technology in ornamental fish culture

Many species of ornamental fish, includingboth egg-layers and livebearers, exhibit a marked sexualdimorphism due to the more pigmented bodies and larger finsusually observed in males. This results in male fish commandingup to four times the price of females. Because of this pricediscrepancy, the culture of monosex (all-male) stocks ofornamental fish could be of a significant economic advantage.This paper outlines the current sex reversal technology alreadydeveloped for several fish species important for aquaculture andexamines its potential applicability to ornamental fish culture.The methods to obtain all-male stocks include direct androgentreatment and the production of YY males. The direct approach iseasy to implement and straightforward. However, in somelivebearers such as the guppy, treatment of newly born fry iscomplicated because they already have sexually differentiatinggonads and the masculinization may be temporary. In this regard,the paper stresses the importance of correctly timing treatmentin relation to gonadal development to achieve permanentmasculinization