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Most pathogens start the process of infection at the mucosal surfaces and therefore the mucosal immune response plays an essential role in the course of the infection. Due to the Senegalese sole (Solea senegalensis Kaup) condition of flatfish, the present comparative study aimed to analyse several immune-related enzymes as well as the bactericidal activity in the skin mucus from ocular and blind sides. For this purpose, Senegalese sole juveniles were bath challenged with a sub-lethal dose of Tenacibaculum maritimum for 24 h and sampled at 1, 2 and 3 weeks. The haematological profile and immune-related parameters were also measured in plasma in order to evaluate the systemic immune response after T. maritimum challenge. Results from this study showed that most parameters tested increased in skin mucus of bath challenged fish compared to unchallenged ones. In contrast, the sub-lethal dose tested did not influence the haematological profile including peripheral numbers the different leucocyte types. No variations were observed in plasma lysozyme, peroxidase, protease and haemolytic complement activities between unchallenged and bath challenged fish. This study suggests that the studied innate immune-related molecules are constitutively present in both skin mucus sides but at different levels. Interestingly, the levels of most parameters measured were higher on the ocular side than on the blind side, possibly due to the higher exposure to invasion by waterborne microorganisms on this side. Therefore, the present study brings some insights regarding local immune responses after bacterial challenge in skin mucus from the ocular and blind sides in one of the most valuable flatfish species in southern Europe. Image 1 • Systemic and local immune responses of Senegalese sole bath-challenged with T. maritimum were evaluated. • A comparative study was carried out in skin mucus of Senegalese sole from ocular and blind sides. • Immune parameters increased in skin mucus of challenged fish compared to unchallenged ones. • At systemic level no variations were found between unchallenged and challenged groups. • The most parameters measured were higher on the ocular side than on the blind side. [ABSTRACT FROM AUTHOR]

This work aims at studying the efficacy of low doses of gaseous ozone in postharvest control of the table grape sour rot, a disease generally attributed to a consortium of non- Saccharomyces yeasts (NSY) and acetic acid bacteria (AAB). Sour rot incidence of wounded berries, inoculated with 8 NSYstrains, or 7 AAB, or 56 yeast-bacterium associations, was monitored at 25 °C up to six days. Sour rot incidence in wounded berries inoculated with yeast-bacterium associations resulted higher than in berries inoculated with one single NSY or AAB strain. Among all NSY-AAB associations, the yeast-bacterium association composed of Candida zemplinina CBS 9494 (Cz) and Acetobacter syzygii LMG 21419 (As) showed the highest prevalence of sour rot; thus, after preliminary in vitro assays, this simplified As-Cz microbial consortium was inoculated in wounded berries that were stored at 4 °C for ten days under ozone (2.14 mg m −3 ) or in air. At the end of cold storage, no berries showed sour-rot symptoms although ozonation mainly affected As viable cell count. After additional 12 days at 25 °C, the sour rot index of inoculated As-Cz berries previously cold-stored under ozone or in air accounted for 22.6 ± 3.7% and 66.7 ± 4.5%, respectively. Molecular analyses of dominant AAB and NSY populations of both sound and rotten berries during post-refrigeration period revealed the appearance of new strains mainly belonging to Gluconobacter albidus and Hanseniaspora uvarum species, respectively. Cold ozonation resulted an effective approach to extend the shelf-life of table grapes also after cold storage. [ABSTRACT FROM AUTHOR]

Cohesive sediment dynamics in estuarine systems is a major issue in water quality and engineering problems. Numerical models can help to assess the complex dynamics of cohesive sediments, integrating the information collected in monitoring studies. Following a numerical approach we investigated the main factors that influence the cohesive sediment dynamics in an estuarine system composed of large mudflats (Tagus estuary, Portugal). After a spin up period of the bottom layer and considering the combined effect of waves and currents on the bottom shear stress, the dynamics of cohesive sediment during the fortnightly and daily erosion–sedimentation cycle was properly reproduced by the model. The results of cohesive suspended sediments were validated with data from sixteen monitoring stations located along the estuary and turbidity data measured by two multiparametric probes. The hydrodynamics were previously validated by harmonic analysis and with ADCP data. Although tidal currents are the major cause of cohesive sediment erosion, the results suggest that wind waves also play an important role. The simulated sediment mass involved in the fortnightly tidal cycle was in the same order of magnitude of the annual load from the rivers, as observed in previous studies based on field data. [ABSTRACT FROM AUTHOR]

Abstract: Organisms living in coastal ecosystems are frequently subjected to anthropogenic pressures such as metals. Metals, especially those not required for metabolic activity (e.g. mercury, lead and cadmium) can be toxic even at quite low concentrations not only to organisms that accumulate them, but also to their consumers. Throughout the world, Ruditapes decussatus and Ruditapes philippinarum have been successfully commercialised for human consumption and for monitoring environmental conditions such as contamination. These two clam species share similar habitats and requirements, successfully competing both in the natural environment and in aquaculture farms. Because differences in metal accumulation may exist between R. decussatus and R. philippinarum, different risks to public health may overcome as well as distinct ecological implications. The effect of depuration on the metal burden and biochemical status of both clams species may also diverge and since the information available is subjective and scarce, the aims of the present study were to: 1) assess the total metal accumulation and intracellular partitioning, at natural conditions, in the two clam species collected at the same site; 2) evaluate the effect of depuration as a mean of reducing the levels of distinct elements, assessing also the effect of depuration time (2 and 7 days); 3) investigate the efficiency of depuration by biochemical status of the two bivalve species, evaluating changes in lipid peroxidation and activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and of glutathione S-transferase (GST). Metal chelation by metallothioneins (MTs) was also determined. The results obtained showed that concentration of elements in clams was low, presenting very similar concentration levels for all elements. The present work further demonstrated that the total element concentration decreased in the shorter depuration period (2 days) and that R. decussatus and R. philippinarum partitioned elements preferentially in the insoluble fraction. The percentage of elements in the soluble fraction was lower in the longer depuration period, reducing the dietary bioavailability of elements and thus the health risk to consumers of depurated bivalves. In general, LPO, CAT, SOD and GSTs showed a decreased from environmental to depuration conditions, revealing that depuration reduces the oxidative stress that organisms were subjected in the environment. The lower MTs production observed in the longer depuration period, although no significantly different from the remaining periods, may be explained by the distinct metal allocation between both soluble and insoluble fractions. [Copyright &y& Elsevier]

Abstract: The relative impacts of tidal (neap, spring) and river discharge (including a flood event) forcing upon water and sediment circulation have been examined at the rock-bound Guadiana estuary. Near-bed and vertical profiles of current, salinity, turbidity, plus surface suspended sediment concentrations (SSC, at some stations only), were collected at the lower and central/upper estuary during tidal and fortnightly cycles. In addition, vertical salinity and turbidity profiles were collected around high and low water along the estuary. Tidal asymmetry produced faster currents on the ebb than on the flood, especially at the mouth. This pattern of seaward current dominance was enhanced with increasing river flow, due to horizontal advection that was confined within the narrow estuarine channel. The freshwater inputs and, at a degree less, the tidal range controlled the vertical mixing and stratification importance. Well-mixed (spring) and partially stratified (neap) conditions alternated during periods of low river flows, with significant intratidal variations induced by tidal straining (especially at the partially stratified estuary). Highly stratified conditions developed with increasing river discharge. Intratidal variability in the pycnocline depth and thickness resulted from current shear during the ebb. A salt wedge with tidal motion was observed at the lower estuary during the flood event. Depending on the intensity of turbulent mixing, the residual water circulation was dominantly controlled either by tidal asymmetry or gravitational circulation. The SSC was governed by cyclical local processes (resuspension, deposition, mixing, advection) driven by the neap-spring fluctuations in tidal current velocities. More, intratidal variability in stratification indicated the significance of tidal pumping at the partially and highly stratified estuary. The estuary turbidity maximum (ETM) was enhanced with increasing current velocities, and displaced downstream during periods of high river discharge. During the flood event, the ETM was expelled out of the estuary, and the SSC along the estuary was controlled by the sediment load from the drainage basin. Under these highly variable river flow conditions, our observations suggest that sand is exported to the nearshore over the long-term (>years). [Copyright &y& Elsevier]

Neural models describe brain activity at different scales, ranging from single cells to whole brain networks. Here, we attempt to reconcile models operating at the microscopic (compartmental) and mesoscopic (neural mass) scales to analyse data from microelectrode recordings of intralaminar neural activity. Although these two classes of models operate at different scales, it is relatively straightforward to create neural mass models of ensemble activity that are equipped with priors obtained after fitting data generated by detailed microscopic models. This provides generative (forward) models of measured neuronal responses that retain construct validity in relation to compartmental models. We illustrate our approach using cross spectral responses obtained from V1 during a visual perception paradigm that involved optogenetic manipulation of the basal forebrain. We find that the resulting neural mass model can distinguish between activity in distinct cortical layers – both with and without optogenetic activation – and that cholinergic input appears to enhance (disinhibit) superficial layer activity relative to deep layers. This is particularly interesting from the perspective of predictive coding, where neuromodulators are thought to boost prediction errors that ascend the cortical hierarchy. [ABSTRACT FROM AUTHOR]

Ready-to-eat asparagus ( Asparagus officinalis L.) is a tasty food with excellent nutraceutical properties. In order to realize a new ready-to-eat product, in this study asparagus's spears were cooked by blanching or microwave, and then dehydrated until they reached a weight loss of 25%, and packaged in air or in modified atmosphere (30% CO 2 + 70% N 2 ). Sensorial, physico-chemical, biochemical, and microbiological parameters were evaluated during a 30 days storage period at 4 °C. The microwave cooking proved to be the most effective method to preserve green colour, improving the overall acceptability of the product. Moreover, the storage in the absence of O 2 and in the presence of high CO 2 percentage was the most effective method to preserve phytochemical composition, total antioxidant capacity, and hygienic quality. In conclusion, asparagus spears cooked by microwave, semi-dried, packaged in modified atmosphere and stored at 4 °C for 30 days retained their quality and sensorial properties. [ABSTRACT FROM AUTHOR]

The use of experimental methods to determine consumers' willingness to pay for "quality" food has been gaining importance in scientific research. In most of the empirical literature on this issue the experimental design starts with blind tasting, after which information is introduced. It is assumed that this approach allows consumers to elicit the real value that they attach to each of the features added through specific information. In this paper, the starting hypothesis is that this technique overestimates the weight of the features introduced by information in consumers' willingness to pay when compared to a real market situation, in which consumers are confronted with all the information at once. The data obtained through contingent valuation in an in-store setting was used to estimate a hedonic model aiming at assessing consumers' willingness to pay (WTP) for the feature "geographical origin of the variety" of pears and apples in different information scenarios: i) blind tasting followed by extrinsic information and ii) full information provided at once. The results show that, in fact, features are more valued when gradually added to background information than when consumers receive all the information from the beginning. [ABSTRACT FROM AUTHOR]

Highlights: [•] Cytokines were reliably measured in plasma in Nigerian women using Luminex assays. [•] Cytokine levels were not associated with HPV detection at the cervix. [•] A possible exception is inverse associations between eotaxin and carcinogenic HPV. [•] Eotaxin findings suggest innate immunity may play a role in HPV persistence. [ABSTRACT FROM AUTHOR]