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Abstract Geotechnical maps of suitability for urbanization can provide directives for land use in terms of susceptibility to disasters. This paper presents methodological innovations for the development of these maps by incorporating hydrographic basin analysis in a case study conducted in the municipality of Itapevi. The Shalstab (Shallow Slope Stability) model evaluated the susceptibility of an area to landslides and correlated events. Wet zones were mapped by combining the Hand (Height to the Nearest Drainage) model with floodplain mapping and proximity to concave slopes. Participatory mapping delineated critical flood areas and possible impacts of land use on sub-basins. Urbanization trends were modeled using multivariate kernel analysis. This study presents perspectives on disaster risk management integrated with those of basin management.

Aptasensors have a great potential for environmental monitoring, particularly for real-time on-site detection of aquatic toxins produced by marine and freshwater microorganisms (cyanobacteria, dinoflagellates, and diatoms), with several advantages over other biosensors that are worth considering. Freshwater monitoring is of vital importance for public health, in numerous human activities, and animal welfare, since these toxins may cause fatal intoxications. Similarly, in marine waters, very effective monitoring programs have been put in place in many countries to detect when toxins exceed established regulatory levels and accordingly enforce shellfish harvesting closures. Recent advances in the fields of aptamer selection, nanomaterials and communication technologies, offer a vast array of possibilities to develop new imaginative strategies to create improved, ultrasensitive, reliable and real-time devices, featuring unique characteristics to produce and amplify the signal. So far, not many strategies have been used to detect aquatic toxins, mostly limited to the optic and electrochemical sensors, the majority applied to detect microcystin-LR using a target-induced switching mode. The limits of detection of these aptasensors have been decreasing from the nM to the fM order of magnitude in the past 20 years. Aspects related to sensor components, performance, aptamers sequences, matrices analyzed and future perspectives, are considered and discussed. ; We also would like to thank to EMERTOX (grant 734748), funded by H2020-MSCA-RISE 2016, and the Project CY-SENSORS (grant no. 032359), co-financed by COMPETE 2020, Portugal 2020 and the European Union through the ERDF, and by FCT through national funds. ...

Harmful Algal Blooms (HAB) are complex to manage due to their intermittent nature and their severe impact on the economy and human health. The conditions which promote HAB have not yet been fully explained, though climate change and anthropogenic intervention are pointed as significant factors. The rise of water temperature, the opening of new sea canals and the introduction of ship ballast waters all contribute to the dispersion and establishment of toxin-producing invasive species that promote the settling of emergent toxins in the food-chain. Tetrodotoxin, ciguatoxin, palytoxin and cyclic imines are commonly reported in warm waters but have also caused poisoning incidents in temperate zones. There is evidence that monitoring for these toxins exclusively in bivalves is simplistic and underestimates the risk to public health, since new vectors have been reported for these toxins and as well for regulated toxins such as PSTs and DSTs. In order to avoid public health impacts, there is a need for adequate monitoring programs, a need for establishing appropriate legislation, and a need for optimizing effective methods of analysis. In this review, we will compile evidence concerning emergent marine toxins and provide data that may indicate the need to restructure the current monitoring programs of HAB.

This article presents a proposal for a methodology to demarcate and characterize areas that might be conducive to aquifer recharge. The guiding principle is the hydrogeological inference of areas uphill from springs. A kriging interpolation plane of the elevation of the springs is the basis for the delimitation of these areas. The characterization of recharge potential rests on lithostratigraphy, geomorphology, and soil studies, on climatological data, and on altimetric differential of springs and downstream watercourses. The maps suggest that the Western portion of the Paracatu basin would hold greater potential for recharge, followed by highland plateaus and table lands. These cartographic products may be useful to integrate the management of water resources and land use.

Natural products are interesting sources for drug discovery. The natural product oxadiazine Nocuolin A (NocA) was previously isolated from the cyanobacterial strain Nodularia sp. LEGE 06071 and here we examined its cytotoxic effects against different strains of the colon cancer cell line HCT116 and the immortalized epithelial cell line hTERT RPE-1. NocA was cytotoxic against colon cancer cells and immortalized cells under conditions of exponential growth but was only weakly active against non-proliferating immortalized cells. NocA induced apoptosis by mechanism(s) resistant to overexpression of BCL family members. Interestingly, NocA affected viability and induced apoptosis of HCT116 cells grown as multicellular spheroids. Analysis of transcriptome profiles did not match signatures to any known compounds in CMap but indicated stress responses and induction of cell starvation. Evidence for autophagy was observed, and a decrease in various mitochondrial respiration parameter within 1 h of treatment. These results are consistent with previous findings showing that nutritionally compromised cells in spheroids are sensitive to impairment of mitochondrial energy production due to limited metabolic plasticity. We conclude that the antiproliferative effects of NocA are associated with effects on mitochondrial oxidative phosphorylation. ; Funding Agencies|Structured Program of R&D&I INNOVMAR-Innovation and Sustainability in the Management and Exploitation of Marine Resources - Northern Regional Operational Program (NORTE2020) through the European Regional Development Fund (ERDF) [NORTE-01-0145-FEDER-000035]; project CYANCAN-Uncovering the cyanobacterial chemical diversity: the search for novel anticancer compounds - NORTE 2020, Portugal 2020 [PTDC/MEDQUI/30944/2017]; European Union through the ERDF; Foundation for Science and Technology; FCT [SFRH/BPD/112287/2015, SFRH/BD/108314/2015]

While the benefits of common and public goods are shared, they tend to be scarce when contributions are provided voluntarily. Failure to cooperate in the provision or preservation of these goods is fundamental to sustainability challenges, ranging from local fisheries to global climate change. In the real world, such cooperative dilemmas occur in multiple interactions with complex strategic interests and frequently without full information. We argue that voluntary cooperation enabled across overlapping coalitions (akin to polycentricity) not only facilitates a higher generation of non-excludable public goods, but it may also allow evolution toward a more cooperative, stable, and inclusive approach to governance. Contrary to any previous study, we show that these merits of multi-coalition governance are far more general than the singular examples occurring in the literature, and they are robust under diverse conditions of excludability, congestion of the non-excludable public good, and arbitrary shapes of the return-to-contribution function. We first confirm the intuition that a single coalition without enforcement and with players pursuing their self-interest without knowledge of returns to contribution is prone to cooperative failure. Next, we demonstrate that the same pessimistic model but with a multi-coalition structure of governance experiences relatively higher cooperation by enabling recognition of marginal gains of cooperation in the game at stake. In the absence of enforcement, public-goods regimes that evolve through a proliferation of voluntary cooperative forums can maintain and increase cooperation more successfully than singular, inclusive regimes. ; Supported by US Defense Advanced Research Projects Agency (D17AC00005), National Science Foundation grant GEO-1211972, and Fundacao para a Ciencia e Tecnologia (FCT) through grants PTDC/MAT/STA/3358/2014, PTDC/EEI-SII/5081/2014, and UID/BIA/04050/2013. P.M.H. was supported by the Walbridge Fund at the Princeton Environmental ...

This article belongs to the Special Issue Advances in the Toxicity Mechanisms of Microcystins Revealed by Omics Approaches ; Microcystins (MCs) are hepatotoxins produced by some cyanobacteria. They are cyclic peptides that inhibit the serine/threonine protein phosphatases (PPs) PP1 and PP2A, especially PP2A. The inhibition of PP2A triggers a series of molecular events, which are responsible for most MC cytotoxic and genotoxic effects on animal cells. It is also known that MCs induce oxidative stress in cells due to the production of reactive oxygen species (ROS). However, a complete characterization of the toxic effects of MCs is still not accomplished. This study aimed to clarify additional molecular mechanisms involved in MC-LR toxicity, using Saccharomyces cerevisiae as eukaryotic model organism. First, a shotgun proteomic analysis of S. cerevisiae VL3 cells response to 1 nM, 10 nM, 100 nM, and 1 µM MC-LR was undertaken and compared to the control (cells not exposed to MC-LR). This analysis revealed a high number of proteins differentially expressed related with gene translation and DNA replication stress; oxidative stress; cell cycle regulation and carbohydrate metabolism. Inference of genotoxic effects of S. cerevisiae VL3 cells exposed to different concentrations of MC-LR were evaluated by analyzing the expression of genes Apn1, Apn2, Rad27, Ntg1, and Ntg2 (from the Base Excision Repair (BER) DNA repair system) using the Real-Time RT-qPCR technique. These genes displayed alterations after exposure to MC-LR, particularly the Apn1/Apn2/Rad27, pointing out effects of MC-LR in the Base Excision Repair system (BER). Overall, this study supports the role of oxidative stress and DNA replication stress as important molecular mechanisms of MC-LR toxicity. Moreover, this study showed that even at low-concentration, MC-LR can induce significant changes in the yeast proteome and in gene expression. ; Key Contribution: The results of this study reveal molecular mechanisms of MC-LR toxicity in yeast related with the production of ROS, oxidative stress, and genotoxicity. ; This research was funded by the European Regional Development Fund (ERDF) through the COMPETE e Operational Competitiveness Program and national funds through FCT (Foundation for Science and Technology) grant to E. Valerio (SFRH/BPD/75922/2011). It was also funded by the Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 through national funds provided by FCT—Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the program PT2020. This work has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 823860 (TOXICROP). ; info:eu-repo/semantics/publishedVersion