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Risks with regard to hypertensive period right after Ahmed glaucoma control device implantation.
The development of sustainable tourism models has been widely discussed in the economic literature. If on the one hand the demand for tourism has grown in recent years, on the other it is necessary to have adequate planning and political tools. The problems of sustainable tourism appear more complex when sustainable tourism involves development opportunities that require the support of the local community and the management of natural resources which are generally common goods. In these circumstances, new management structures need to be created, which can both meet the needs of the local community and ensure adequate management of natural resources. This study analyzes the connections between sustainable tourism models and natural resource management considering the case of the forest landscape. The study highlights how the correct management of public goods can lead, on the one hand, to satisfying demand and, on the other hand, creating opportunities for sustainable development of the environment.The Violet Crown Cup, Sarcosphaera coronaria, is a rather inconspicuous mushroom, but with an interesting and unresolved mystery. In earlier days, the mushroom was considered edible, but several poisonings were reported in the early 20th century. selleck chemicals The reason for the seemingly sporadic toxicity of S. coronaria is still unknown. One possible explanation is arsenic, since Crown Cups can take up high amounts of this element. We investigated the arsenic concentration and arsenic speciation in S. coronaria with inductively coupled plasma mass spectrometry (ICPMS) and HPLC coupled to ICPMS and found up to incredible 0.9% As (dry mass). Most of it was present as methylarsonic acid (MA), a less toxic form of this element. However, low concentrations of the highly toxic methylarsonous acid [MA (III)] were also detected. The amounts were too low to pose an acute risk for consumers, but the concentration of MA (III) significantly increased during simulated gastric digestion. We could not unambiguously identify arsenic as the toxic constituent of S. coronaria, but we demonstrated that the extremely toxic MA (III) can be formed under certain circumstances, which should be carefully investigated in future.Although PM2.5 toxicity is known to be related to its chemical composition, the effect of interactions among various particles' components on the toxicity is not well explored. To understand these interactions, especially metals and organic compounds on PM2.5 cytotoxicity, we chose several redox-active substances known to be present in the ambient particles such as metals (Cu, Fe, and Mn) and quinones [9,10-phenanthraquinone (PQ), 1,2-naphthoquinone (1,2-NQ), 1,4-naphthoquinone (1,4-NQ), and 5-hydroxy-1,4-naphthoquinone (5,H-1,4-NQ)]. Cytotoxicity was assessed through a Chinese hamster ovary (CHO) cells assay and expressed by a median lethal concentration (LC50). Two methods were employed to assess the interactions. In the first method, we tested the impact of nontoxic level of a component on the LC50 of other components. In the second method, we mixed two components in different concentration ratios to expose the cells and calculated a mixture toxicity index (MTI). MTI is a composite value to quantify the nature of interactions such that the interactions are considered synergistic when MTI > 1, additive when 0 less then MTI ≤ 1 and antagonistic when MTI less then 0. The interactions between quinones and metals were largely synergistic by both methods. To further assess the environmental relevance of these mixtures, we extracted organic compounds termed as water-soluble Humic-like substances (HULIS) from real ambient PM samples and mixed them with individual metals. A similar pattern, as observed from the interaction of quinones and metals, was found. Moreover, the interactions became more synergistic as the relative concentration of metals with respect to water-soluble HULIS was decreased in these mixtures. With environmentally relevant mass concentration ratios of organics to metals (75-7500), the interactions were strongly synergistic (MTI = 1-115). These results indicate the importance of incorporating the interaction among various PM components for estimating the net toxicity of ambient PM2.5.Several studies show that the elemental content of honey entirely depends on the botanical and geographical origin, but the information is incomplete regarding its time-dependent composition changes. Twenty-six acacia and three honey samples with unknown botanical origin were collected between 1958 and 2018 and analysed for elemental composition by Microwave Plasma Atomic Emission Spectrometry (MP-AES). The elemental analysis was coupled with independent dating method by Accelerator Mass Spectrometry (AMS) to confirm the calendar age of the honey samples and test the possibility of radiocarbon based dating of bee products, which has not been applied before. According to the analytical measurements and statistical analysis, we can conclude that the elemental composition shows change with time in the acacia honey during the last five decades. We have proven that honey preserves carbon isotopic and elemental information of its production time and thus can be applied as an environmental indicator (e.g. trace urban pollutants, precipitation, local industrial or agricultural emission) in reconstruction studies by analysing the non-degradable mineral content. Our results further show that acacia honey is a suitable material for radiocarbon dating, proved by the results compared to the atmospheric radiocarbon bomb-peak. link2 The new approach presented for investigation of honey by radiocarbon-based age determination coupled with elemental analysis can be used in biological, dietary, archaeological or other multidisciplinary studies as well. Some samples show slightly depleted radiocarbon content. This could be an indication of local fossil CO2 emission. Based on these depleted 14C results, honey could be used for atmospheric monitoring of fossil CO2 urban or industrial hot-spots.MHC-1 is a halogenated natural product (HNP) produced by the red seaweed Plocamium cartilagineum. MHC-1 concentrations of 550-2700 μg/g dry weight were found in Plocamium collected by divers at Heligoland (Germany). Compared to that MHC-1 concentrations were much lower in samples collected on beaches in Ireland and Portugal. Exposure of leaves of Plocamium to sunlight showed that MHC-1 was readily transformed by hydrodebromination. At Heligoland in March, MHC-1 (δ13C value -45.2‰) was lighter in carbon by ~15‰ compared to the bulk δ13C value (‰) of Plocamium (-30.7‰). Collected at the same time and location at Heligoland, samples of Halichondria and Mastocarpus sp. were richer in carbon (by ~10‰) as Plocamium. However, the δ13C value of MHC-1 in Halichondria (-44.6‰) and Mastocarpus sp. (-42.1‰) was as negative as in Plocamium. This was indirect proof that MHC-1 was produced by Plocamium and then released into the water phase from where it then was bioconcentrated by Halichondria and Mastocarpus sp. In agreement with that, concentrations of MHC-1 in Halichondria and Mastocarpus sp. were much lower than in Plocamium. In addition, a potential isomer of MHC-1 (compound X) was detected in all samples from Heligoland at ~2% of the MHC-1 level.There is growing evidence that river temperatures are increasing under climate change, which is expected to be exacerbated by increased abstractions to satisfy human water demands. Water temperature research has experienced crucial advances, both in terms of developing new monitoring and modelling tools, as well as understanding the mechanisms of temperature feedbacks with biogeochemical and ecological processes. However, water practitioners and regulators are challenged with translating the widespread and complex technological, modelling and conceptual advances made in river temperature research into improvements in management practice. This critical review provides a comprehensive overview of recent advances in the state-of-the-art monitoring and modelling tools available to inform ecological research and practice. In so doing, we identify pressing research gaps and suggest paths forward to address practical research and management challenges. The proposed research directions aim to provide new insights into spatio-temporal stream temperature dynamics and unravel drivers and controls of thermal river regimes, including the impacts of changing temperature on metabolism and aquatic biogeochemistry, as well as aquatic organisms. The findings of this review inform future research into ecosystem resilience in the face of thermal degradation and support the development of new management strategies cutting across spatial and temporal scales.The nitritation step is essential when the anammox process is focused, and alternative technologies to achieve partial nitritation-anammox are required. Rotating Biological Contactors (RBCs) are a promising and cost-effective technology, allowing the development of aerobic and anoxic zones in the biofilm, coupled to low energy consumption. This study evaluated nitritation in a RBC with two discs rotation strategies continuous and intermittent. Continuous rotation resulted in high dissolved oxygen (DO) concentrations and was not favorable for achieving stable nitritation. However, intermittent rotation, coupled with a nitrogen load of 1000 g N·m-3·d-1 and a HRT of 12 h, decreased DO by 77.8% and resulted in nitritation efficiencies of 45.3%. FISH analyses suggested that simultaneous partial nitritation/anammox (PN/A) could also be favored. These results indicated that intermittent rotation may be a core strategy for producing an anammox-suitable effluent or even to promote PN/A in RBCs, upgrading their applicability for wastewater treatment.Portmán Bay is one of the most contaminated and chronically impacted coastal marine areas of the world. Here, from the 1957 to 1990, about 60 million tons of mine tailings from the processing of sulfide ores were dumped directly at the shoreline. The resulting deposit provides a unique opportunity to assess the impact of mine tailings on coastal marine ecosystems after ca 30 years since the discharge has ceased. We investigated meiofaunal abundance, biomass and biodiversity along a gradient of metal concentration that overlaps with a bathymetric gradient from 30 to 60 m depth. Despite the localized presence of extremely high concentration of metals, the bay was not a biological desert, but, nevertheless, was characterized by evident signs of impact on benthic diversity. Meiofaunal variables increased significantly with decreasing metal contamination, eventually reaching values comparable to other uncontaminated coastal sediments. Our results show that mine tailings influenced the spatial distribution of meiofaunal taxa and nematode species composition. In particular, we report here that the bay was characterized by the dominance of nematode opportunistic species tolerant to high metal concentration. The effects of mine tailing discharge on meiofaunal biodiversity and composition were still evident ca 30 years after the end of the mining activities. link3 Overall, this study provides new insights on the potential impact of mine tailings disposal and metal contamination in coastal sediments, and, can also contribute to predict the potential long-term consequences of ever-expanding deep-sea mining industry on benthic environments.
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