1,069 research outputs found

    Biomonitoring survey of the hydrographical network in a MAB UNESCO Biosphere Reserve

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    The knowledge of microbial biodiversity (bacteria and protists) in aquatic ecosystems is far from complete. This is mainly due to the inadequacy of conventional taxonomic identifications, which are based on the discrimination of diacritical morphological traits. Further, investigations are mainly focused on specific lake and river typologies that are usually also of interest for economic exploitation, often disregarding the small and/or ephemeral water bodies. Nevertheless, due to their physiographical complexity and temporal dynamics, these neglected hydrographical elements can host a vast microbial diversity. In order to fill the gap in the biodiversity estimates in the Alpine region, we carried out a survey using high throughput sequencing (HTS) of 16S and 18S rDNA markers from water and sediments collected in the MAB UNESCO Alpi Ledrensi and Judicaria Biosphere Reserve (Project Acqua Viva). The study sites are located between Lake Garda and the Brenta Dolomites, and include natural environments in a semi- anthropized Alpine context with agricultural and tourist vocation. The survey was carried out during the summer 2019, covering 20 sites of different sizes and characteristics, including lakes, alpine pasture ponds and wetlands. The results allowed disclosing a high number of amplicon sequence variants (ASVs) belonging to a wide variety of bacterial and protists groups, and significant differences linked to lake and sample typologies. Despite a wide presence of potentially toxigenic cyanobacteria, microcystins and anatoxin-a were detected only in a few water bodies, including Lake Ledro, which showed the presence of both Planktothrix rubescens and Tychonema bourrellyi in the pelagic samples

    A comparison of efficient permutation tests for unbalanced ANOVA in two by two designs--and their behavior under heteroscedasticity

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    We compare different permutation tests and some parametric counterparts that are applicable to unbalanced designs in two by two designs. First the different approaches are shortly summarized. Then we investigate the behavior of the tests in a simulation study. A special focus is on the behavior of the tests under heteroscedastic variances.Comment: 20 pages, 9 figures, Working Paper of the Department of Management And Enigineering of the University of Padov

    Potential impact of dreissenids species in relation to the first report of quagga mussel (Dreissena bugensis) at the end of winter 2022 in Lake Garda (Northern Italy)

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    Along with Dreissena polymorpha (zebra mussel), Dreissena bugensis (quagga mussel) is considered one of the most widespread and successful invasive species in Europe, Russia, and North America. The quagga mussel is a bivalve mollusc of the dreissenids family originating from the estuarine region of the rivers Dnieper and Southern Bug (Black Sea). The spread in Europe began after the 1940s and was associated with construction of canal-river systems. D. polymorpha was observed in Lake Garda since the end of the 1960s. In the last years, D. bugensis was found in the northern perialpine region and in late winter 2022 it was identified along the eastern shores of Lake Garda. Both species are defined as ecosystems engineers because they can strongly change the substrate structure, causing great economic damage in water pipes, potable water treatment plants, and port constructions. Moreover, they can affect resource availability for the other species. A few significant ecological differences between the two species suggest that the impact of quagga mussel could be even larger compared to that caused by zebra mussel. In this poster we will discuss the main expected ecological impacts following the introduction of quagga mussel into new aquatic habitats

    Considering mesohabitat scale in ecological impact assessment of sediment flushing

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    Benthic macroinvertebrates respond to several factors characterizing the physical habitats, as water depth, current and streambed substrate. Thus, anthropogenic disturbances altering these factors may have different effects on benthos, also depending on mesohabitats. These disturbances include sediment flushing operations, commonly carried out to recover reservoir capacity, and investigating their effects at mesohabitat scale could be relevant for an adequate ecological impact assessment of these operations. Here, we compared benthic macroinvertebrate communities sampled before and after a controlled sediment flushing operation in three different mesohabitats (a pool, a riffle and a step-pool) of an Alpine stream. Contrary from expectations, the composition of macroinvertebrate assemblages was not significantly different among mesohabitats. Moreover, the impact of sediment flushing was more significant in terms of density rather than in richness. Two stressor-specific indices were tested, but only one (the Siltation Index for LoTic EcoSystems - SILTES) clearly detected the impact of sediment flushing on the macroinvertebrate community structure. Finally, some differences in the temporal trajectories and recovery times to pre-flushing conditions were observed among mesohabitats, both if the three mesohabitats were considered separately and if all their possible combinations were accounted for. Particularly, riffle was the most sensitive mesohabitat, not fully recovering one year after the sediment disturbance

    Treatment of a Severe Pediatric Lyell Syndrome with Amniotic Membrane: Case Report and Histological Findings

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    Background: Lyell Syndrome (TEN, Toxic epidermal necrolysis) represents a medical emergency particularly in pediatric patients in whom the massive skin damage can quickly lead to multi-organ dysfunction and death. Prompt restoration of the physiologic mucosal/cutaneous barrier is mandatory. The use of amniotic membranes has been described in the treatment of ophthalmic Lyell Syndrome, but its use has not yet been adopted for the management of larger cutaneous wounds. Study Hypothesis: Here we report the use of amniotic membranes in a pediatric case of severe Lyell Syndrome with complete skin surface, ocular and mucosal involvement with life threating presentation. Methods: A 7-year old female was admitted to our Burn Centre for severe cutaneous/mucosal exfoliation (100% Total body surface area, TBSA) as a result of an adverse reaction to ibuprofen administration. Supportive fluid administration, cardiac-pulmonary assistance and pain management were complemented by serial grafting of amniotic membranes on all affected areas to provide coverage of the exfoliated skin/mucosa. Biopsies were obtained to monitor histological skin changes. Results: The patient showed an excellent response to amniotic membrane treatment, with rapid restoration of mucosal and cutaneous layers in the grafted areas. This resulted in a decreased need for dressing changes, avoidance of additional surgeries and a reduced dependence on supportive therapy. Lower pain levels than usually expected led to a reduced need for narcotic pain medications and allowed for early physical rehabilitation and a short hospital stay. Histology confirmed evidence of topical immune-modulation in treated areas (reduction of inflammatory infiltrate). Conclusion: As we tested in numerously TEN and burn pediatric injuries Amniotic membranes with their regenerative and immune-modulatory effects may represent an life saving treatment even in the worst cases of pediatric Lyell syndrome

    Expansion of cyanobacteria outbreaks in the Alpine region: first report of an intense Microcystis bloom in Lake Serraia

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    Lake Serraia is a small eutrophic dimictic lake located in the town of Baselga di Pinè, in the Province of Trento. The lake has an average depth of 7 m and a maximum depth of 18 m and is mainly used for recreational activities. During the last decade, summer blooms of non-toxigenic populations of Dolichospermum spp. were documented over the entire lake. Conversely, at the end of August 2023, an intense toxigenic bloom of Microcystis aeruginosa developed over several weeks, resulting in a bathing ban by the local authorities. Besides the usual monitoring for the control of bathing waters, a few opportunistic samples were collected for microscopical examinations, toxins analyses using LC-MS techniques, and strain isolation and cultivation. In the areas where the surface scums developed, the MC-LR and MC-RR congeners of microcystins showed concentrations of 200 μg L-1 and 42 μg L-1, respectively. The bloom episodes documented in Lake Serraia are part of a more general increasing trend of cyanobacterial outbreaks actively documented in the southern Alpine region. Besides persisting high trophic status, as in Lake Serraia, the causes were also connected to the general increasing temperature trends at the global and local levels

    Soft Tissue Reconstruction of the Posterior Trunk after Tumor Excision: A Surgical Algorithm

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    Background: The posterior trunk has been considered a challenging area to reconstruct following soft tissue tumor excision because of the shortage of local donor sites. The advent of innovative procedures such as perforator flaps has radically changed this perspective and offered a new approach to the problem. Methods: Upon a review of the literature and the personal experiences of the senior author, an algorithm is developed according to the most updated procedure, combined with more conventional options that maintain a role in decision-making. Results: The upper back latissimus dorsi and trapezium flap are still the most reliable approaches, while perforator flaps based either on the circumflex scapular arteries or the transverse cervical artery represent a more refined option. In the middle third, few indications remain for the reverse latissimus dorsi, while the gold standard is represented by local perforator flaps based on the posterior intercostal system. In the lower back, conventional VY advancement flaps are still a safe and effective option in the sacral area, and perforator flaps based on posterior intercostal arteries, lumbar arteries and superior gluteal arteries are the first choice in most cases. Conclusions: Using perforator flaps significantly improved soft tissue reconstruction in the posterior trunk
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