Surface integrity could limit the potential of concrete as a bio-enhanced material in the marine environment

Coastal sprawl is among the main drivers of global degradation of shallow marine ecosystems. Among artificial substrates, quarry rock can have faster recruitment of benthic organisms compared to traditional concrete, which is more versatile for construction. However, the factors driving these differences are poorly understood. In this context, this study was designed to compare the intertidal and subtidal benthic and epibenthic assemblages on concrete and artificial basalt boulders in six locations of Madeira Island (northeastern Atlantic, Portugal). To assess the size of the habitat, the shorelines in the study area were quantified using satellite images, resulting in >34 % of the south coast of Madeira being artificial. Benthic assemblages differed primarily between locations and secondarily substrates. Generally, assemblages differed between substrates in the subtidal, with lower biomass and abundance in concrete than basalt. We conclude that these differences are not related to chemical effects (e.g., heavy metals) but instead to a higher detachment rate of calcareous biocrusts from concrete, as surface abrasion is faster in concrete than basalt. Consequently, surface integrity emerges as a factor of ecological significance in coastal constructions. This study advances knowledge on the impact and ecology of artificial shorelines, providing a baseline for future research towards ecological criteria for coastal protection and management.

Exploring foraging preference of local fish species towards non-indigenous fouling communities near marinas: Insights from Remote Video Foraging System (RVFS) trials

Non-indigenous species (NIS) spread from marinas to natural environments is influenced by niche availability, habitat suitability, and local biotic resistance. This study explores the effect of indigenous fish feeding behaviour on NIS proliferation using fouling communities, pre-grown on settlement plates, as two distinct, representative models: one from NIS-rich marinas and the other from areas outside marinas with fewer NIS. These plates were mounted on a Remote Video Foraging System (RVFS) near three marinas on Madeira Island. After 24-h, NIS abundance was reduced by 3.5 %. Canthigaster capistrata's preference for marinas plates suggests potential biotic resistance. However, Sparisoma cretense showed equal biting frequencies for both plate types. The cryptogenic ascidian Trididemnum cereum was the preferred target for the fish. Our study introduces a global framework using RVFS for in-situ experiments, replicable across divers contexts (e.g., feeding behaviour, biotic resistance), which can be complemented by metabarcoding and isotopic analysis to confirm consumption patterns.

Drones for litter monitoring on coasts and rivers: suitable flight altitude and image resolution

Multirotor drones can be efficiently used to monitor macro-litter in coastal and riverine environments. Litter on beaches, dunes and riverbanks, along with floating litter on coastal and river waters, can be spotted and mapped from aerial drone images. Items detection and classification are prone to image resolution, which is expressed in terms of Ground Sampling Distance (GSD). The GSD is determined by drone flight altitude and camera properties. This paper investigates what is a suitable GSD value for litter survey. Drone flight altitude and camera setup should be chosen to obtain a GSD between 0.5 cm/px and 1.25 cm/px. Within this range, the lowest GSD allows litter categorization and classification, whereas the highest value should be adopted for a coarser litter census. In the vision of drawing up a global protocol for drone-based litter surveys, this work sets the ground for homogenizing data collection and litter assessments.

Predation facilitates the abundance of biofouling non-indigenous species in estuarine marinas in NE Atlantic Portugal

Harbours are highly modified habitats that differ from natural areas. They are hotspots of non-indigenous species (NIS) and act as stepping-stones in invasive processes. However, local communities can exert biotic resistance against biological invasions through trophic interactions and competition. This study assesses the biotic effects of predation on the recruitment of fouling assemblages in three marinas of NE Atlantic Portugal (Cascais, Setúbal and Sines), with particular emphasis on NIS, using predator exclusion experiments. Predation increased the relative abundance of NIS, mainly Watersipora subatra, in the estuarine marinas of Cascais and Setúbal, while no predation effects were registered in the coastal marina of Sines. Therefore, predation can increase the risk of NIS invasion (biotic facilitation). Furthermore, local ecosystems may have different effects and differ in vulnerability against NIS invasions. Finally, a better understanding of coastal invasive ecology and biotic effects in coastal artificial habitats will improve our capacity for NIS management.

Location and building material determine fouling assemblages within marinas: A case study in Madeira Island (NE Atlantic, Portugal)

Marinas are hubs for non-indigenous species (NIS) and constitute the nodes of a network of highly modified water bodies (HMWB) connected by recreational maritime traffic. Floating structures, such as pontoons, are often the surfaces with higher NIS abundance inside marinas and lead the risk for NIS introduction, establishment and spread. However, there is still little information on how the location within the marina and the substratum type can influence the recruitment of fouling assemblages depending on water parameters and substratum chemical composition. In this study, fouling recruitment was studied using an experimental approach with three materials (basalt, concrete and HDPE plastic) in two sites (close and far to the entrance) in two marinas of Madeira Island (NE Atlantic, Portugal). The structure of benthic assemblages after 6- and 12-months colonization, as well as biotic abundance, NIS abundance, richness, diversity, assemblages' volume, biomass and assemblages' morphology were explored. Differences between marinas were the main source of variation for both 6- and 12-month assemblages, with both marinas having different species composition and biomass. The inner and outer sites of both marinas varied in terms of structure and heterogeneity of assemblages and heterogeneity of morphological traits, but assemblages did not differ among substrata. However, basalt had a higher species richness and diversity while concrete showed a higher bioreceptivity in terms of total biotic coverage than the rest of materials. Overall, differences between and within marinas could be related to their structural morphology. This study can be valuable for management of urban ecosystems, towards an increase in the environmental and ecological status of existing marinas and their HMWB and mitigation coastal ecosystems degradation.

A global-scale screening of non-native aquatic organisms to identify potentially invasive species under current and future climate conditions

The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment areas across all six inhabited continents screened 819 non-native species from 15 groups of aquatic organisms (freshwater, brackish, marine plants and animals) using the Aquatic Species Invasiveness Screening Kit. This multi-lingual decision-support tool for the risk screening of aquatic organisms provides assessors with risk scores for a species under current and future climate change conditions that, following a statistically based calibration, permits the accurate classification of species into high-, medium- and low-risk categories under current and predicted climate conditions. The 1730 screenings undertaken encompassed wide geographical areas (regions, political entities, parts thereof, water bodies, river basins, lake drainage basins, and marine regions), which permitted thresholds to be identified for almost all aquatic organismal groups screened as well as for tropical, temperate and continental climate classes, and for tropical and temperate marine ecoregions. In total, 33 species were identified as posing a 'very high risk' of being or becoming invasive, and the scores of several of these species under current climate increased under future climate conditions, primarily due to their wide thermal tolerances. The risk thresholds determined for taxonomic groups and climate zones provide a basis against which area-specific or climate-based calibrated thresholds may be interpreted. In turn, the risk rankings help decision-makers identify which species require an immediate 'rapid' management action (e.g. eradication, control) to avoid or mitigate adverse impacts, which require a full risk assessment, and which are to be restricted or banned with regard to importation and/or sale as ornamental or aquarium/fishery enhancement.

[Secondary syphilis of gastric location]

We present a case of syphilitic gastropathy manifested by an ulcero-infiltrative lesion in the gastric antrum in a 25 year old man. We obtained a clinical endoscopic cure with specific anti-luetic therapy. The morphologic characteristics, which are usual in this type of disease, are revised and the diagnostic criterion discussed.

A kinetic study of the ouabain-induced efflux of norepinephrine from the dog saphenous vein

Dog saphenous vein strips were incubated with [3H]norepinephrine ([3H]NE), 1.4 microM, after inhibition of the NE-metabolizing enzymes and extraneuronal uptake, and superfused for up to 290 min. From the 70th min onwards the strips were exposed to 10 microM ouabain, some of them being subject to electrical stimulation from the 140th min onwards. Other strips were exposed to either 1, 10 or 100 microM ouabain from the 70th min onwards. The spontaneous efflux of [3H]NE had a long half-time (156 min), and over 90% of the [3H]NE accumulated did not participate in efflux ("bound fraction"). Ouabain, 10 microM, induced a pronounced increase of the rate of efflux of [3H]NE, which was delayed in its onset and reached a maximum at t = 135 min of superfusion. Increasing the concentration of ouabain decreased both the delay to the beginning of the overflow and the time to maximum efflux and increased the maximum rate of efflux. In Ca(++)-free medium (during the superfusion period), the maximum rate of efflux was lower than in Ca(++)-containing medium, but was attained earlier. The bound fraction amounted to 22% when the efflux was induced by 10 microM ouabain in Ca(++)-containing medium, a value unnaffected by electrical stimulation but reduced markedly by omitting calcium. The results support the view that the efflux of [3H]NE induced by ouabain is delayed and that it is both carrier-mediated and due to exocytosis.

Ocular changes in familial amyloidotic polyneuropathy with dense vitreous opacities

Familial amyloid polyneuropathy (FAP) is a hereditary disease which eventually causes serious ocular problems. Seven eyes from patients with FAP 1 were vitrectomised, and the insoluble proteins from the vitreous were purified, the amyloid protein isolated, and the prealbumin characterised with a monoclonal antibody against amyloid fibril protein. Before surgery, visual acuity was very poor, due to abundant deposits in the vitreous, frequently attached to the posterior lens capsule. The pupil had peculiar indentations and the pupillary reflexes were abnormal. Intraocular pressure (IOP) was at the upper limit of normal. In the ocular fundus an intraretinal perifoveal gray ring was sometimes seen. Vitrectomy improved visual acuity, but the reappearance of vitreous deposits reduced it to 8.8/10 after 33.4 months, when treatment was needed for most of the eyes to control IOP. Amyloid and the mutant form of prealbumin characteristic of FAP 1, TTR Met 30, were shown to be present in the vitreous.

Controlled trial of liquid monopolar electrocoagulation in bleeding peptic ulcers

The aim of this study was to evaluate the efficacy and the safety of liquid monopolar electrocoagulation in the endoscopic control of major haemorrhage from peptic ulcers. During the 24-month period of the trial, emergency endoscopy was performed on 480 patients consecutively admitted with acute upper gastrointestinal tract hemorrhage. Ulcers were seen in 168 cases (35%). Seventy-eight of these were included in the trial. Active bleeding was present in 21 cases and stigmata of recent bleeding were observed in 57. Immediate hemostasis was achieved in nine of 11 patients with active bleeding ulcers. However, active bleeding can stop spontaneously (as in four of 10 control patients), which reemphasizes the importance of randomized studies. There was a trend toward hemostatic benefit for the electrocoagulation-treated patients with actively bleeding ulcers. In the group of 31 patients with visible vessels, the electrocoagulation treatment reduced significantly both the rate of rebleeding and the emergency surgery. In the group of 26 patients with other stigmata of recent bleeding (fresh or altered clot, or black spots), only in two cases allocated to placebo treatment occurred rebleeding. These patients are at minimal risk of further bleeding. The results offer support to the contention that liquid monopolar electrocoagulation is a safe and effective method of reducing the incidence of further bleeding and emergency surgery. This new technique has the advantages of low cost, easy maintenance, durability, and portability.

A kinetic study of the release of noradrenaline by electrical stimulation: influence of presynaptic alpha-adrenoceptors

Dog saphenous vein strips were incubated with 1.4 mumol/l 3H-(--)-noradrenaline for 60 min, after inhibition of the noradrenaline-metabolizing enzymes and of extra-neuronal uptake. At the end of the incubation period the strips were perifused for 150 min; cocaine (10 mumol/l) was added to the perifusion fluid from t = 75 min onwards. In some experiments either phentolamine (10 mumol/l) or clonidine (0.1 mumol/l) was also added at this time. Some strips were subjected to electrical stimulation from t = 100 to 150 min of perifusion (t = 0 being the start of perifusion), with frequencies ranging from 0.5 to 13.5 Hz. A compartmental analysis of spontaneous or electrically-induced efflux of 3H-noradrenaline was made. The spontaneous efflux had a long half time (t/2 = 124 min) and most of the 3H-noradrenaline which had accumulated in the strips did not participate in the efflux ("bound fraction", representing 90% of tissue activity at t = 100 min of perifusion). Neither phentolamine nor clonidine modified the half time or the "bound fraction" observed for spontaneous efflux. Electrical stimulation (greater than 0.5 Hz) mobilized only one compartment of noradrenaline, which represented about 50% of the noradrenaline accumulated in the strips. The half time of 3H-efflux induced by electrical stimulation decreased when the frequency increased from 0.5 Hz up to 13.5 Hz. Phentolamine increased the rate of efflux for all frequencies of stimulation and decreased the half time of efflux. However, the releasable pool of noradrenaline was only increased by phentolamine at 0.5 Hz, but not at higher frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)

Differences in the metabolic fate of noradrenaline released by electrical stimulation or by tyramine

Strips of canine saphenous vein were loaded with 3H-noradrenaline (1.4 micrometer) and perifused with Krebs solution and either subjected to field stimulation or exposed to tyramine 40 micrometer. 3H, noradrenaline and its metabolites were determined in the perifusion fluid. Stimulation caused an increase predominantly in noradrenaline, followed by DOPEG, whereas tyramine release DOPEG in larger amounts than noradrenaline. Tyramine had more sustained effects than stimulation. Cocaine (1.6 micrometer) drastically reduced DOPEG efflux due to stimulation, but had no effects on the pattern of release by tyramine. It is concluded that tyramine releases noradrenaline which is deaminated before it reaches the synaptic gap, whereas after stimulation deamination of the transmitter occurs after re-uptake.