Rapid granulation and stable performance of a microalgal-bacterial granular sludge system treating saline wastewater

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Recycling of marine aquaculture wastewater using a microalgae-bacterial granular sludge system

Aquaculture has become the fastest growing animal food-producing sector. In a near future, an intensification of the aquaculture practices is expected to cope with the ever-increasing fish demand. However, for land-based aquaculture farms, this growth implies the capture of higher water volumes from nearby water bodies and, consequently, the discharge of higher volumes of wastewater, containing organic carbon, nutrients, and often recalcitrant pollutants (e.g. pharmaceuticals). The expansion of the land-based aquaculture sector is currently offset due to the lack of space and water supplies, but also due to environmental concerns. Therefore, there is a need for innovative wastewater treatment systems able to reduce energy input, to improve resource use and to reduce the environmental impact. In the present study, microalgae-bacterial granules were developed from a phototrophic microbial consortium autochthonous to the water streams of a marine aquaculture facility. The granular biomass was able to efficiently treat marine aquaculture streams, even when sporadically the antibiotic florfenicol was present, with pollutant reaching levels that allowed water recirculation in fish farms. The ammonium, nitrite, and nitrate concentrations in the treated effluents were below the toxicity limits for marine fish and, the dissolved oxygen levels were within the ideal range for water recirculation. The granules microbial community was dynamic and, its structure was susceptible and adaptable to the changing operational reactor conditions such as the presence of the antibiotic florfenicol. The microbial diversity and functional redundancy within the microbial community seemed to be crucial for the adaptability of the system to the stressors presence. Th symbiosis established between microalgae and bacteria within granules allowed for the effective and environmentally sustainable treatment of marine aquaculture wastewater.info:eu-repo/semantics/publishedVersio

Microalgae-bacterial granular sludge systems - on the road for more sustainable processes in the aquaculture sector

With population growth and stagnation of capture fisheries, the aquaculture sector has been challenged to achieve remarkable production targets to meet the ever-increasing fish demand. However, land-based aquaculture industries need to capture high water volumes from nearby water bodies to ensure an adequate production and, consequently, high wastewater volumes, containing organic carbon, nutrients, and often contaminants of emerging concern, are produced. If not properly handled, aquaculture effluents pose a threat to receiving aquatic ecosystems. The rapid expansion of these industries, facing the increased demand for food worldwide, is only possible if more sustainable practices are adopted. To face the current water shortages and protect water resources, the development of environmentally friendly treatment systems that allow water recirculation is of utmost importance. This work aimed to develop a microalgae-bacteria granular sludge system able to efficiently treat marine aquaculture effluents so they can meet the requirements for recirculation. A photo-sequencing batch reactor was inoculated with a phototrophic microbial consortium obtained from water streams in a marine aquaculture facility and was fed with wastewater mimicking marine aquaculture streams. The aggregation of the microbial biomass occurred rapidly and, on day-21, ca. 49% of the total reactor biomass was in the form of granules. The system exhibited high and stable organic carbon removal (>80%), even when florfenicol, an antibiotic widely used in aquaculture, was present in the wastewater. Concerning the nitrogen content, a high-chemical quality effluent was obtained, complying with ammonium, nitrite, and nitrate concentrations for water recirculation within a marine aquaculture farm, even in periods where florfenicol was present in the wastewater. In addition, the dissolved oxygen levels in the treated effluents where within the ideal range for fish growth thus reducing the need for oxygenation and, consequently, the farms operational costs. Additionally, the coexistence of microalgae and bacteria within the granules allowed to treat wastewater at low air flow rates potentially reducing the energy needed for system’s aeration. Microalgae-bacterial granular sludge systems can contribute for the aquaculture sector sustainability as they enable to reduce energy and water usage whilst ensuring environmental protection.info:eu-repo/semantics/publishedVersio

Bioremediation of coastal aquaculture effluents spiked with florfenicol using microalgae-based granular sludge – a promising solution for recirculating aquaculture systems

Aquaculture is a crucial industry in the agri-food sector, but it is linked to serious environmental problems. There is a need for efficient treatment systems that allow water recirculation to mitigate pollution and water scarcity. This work aimed to evaluate the self-granulation process of a microalgae-based consortium and its capacity to bioremediate coastal aquaculture streams that sporadically contain the antibiotic florfenicol (FF). A photo-sequencing batch reactor was inoculated with an autochthonous phototrophic microbial consortium and was fed with wastewater mimicking coastal aquaculture streams. A rapid granulation process occurred within ca. 21 days, accompanied by a substantially increase of extracellular polymeric substances in the biomass. The developed microalgae-based granules exhibited high and stable organic carbon removal (83-100%). Sporadically wastewater contained FF which was partially removed (ca. 5.5-11.4%) from the effluent. In periods of FF load, the ammonium removal slightly decreased (from 100 to ca. 70%), recovering 2 days after FF feeding ceased. A high-chemical quality effluent was obtained, complying with ammonium, nitrite, and nitrate concentrations for water recirculation within a coastal aquaculture farm, even during FF feeding periods. Members belonging to the Chloroidium genus were predominant in the reactor inoculum (ca. 99%) but were replaced from day-22 onwards by an unidentified microalga from the phylum Chlorophyta (>61%). A bacterial community proliferated in the granules after reactor inoculation, whose composition varied in response to feeding conditions. Bacteria from the Muricauda and Filomicrobium genera, Rhizobiaceae, Balneolaceae, and Parvularculaceae families, thrived upon FF feeding. This study demonstrates the robustness of microalgae-based granular systems for aquaculture effluent bioremediation, even during periods of FF loading, highlighting their potential as a feasible and compact solution in recirculation aquaculture systems.info:eu-repo/semantics/publishedVersio

Selecting indicators to monitor and assess environmental health in a Portuguese urban setting : a participatory approach

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Environmental health (EH) is influenced by complex interactions between health and the built and natural environments, there being little research on its specificities in urban settings. The use of suitable indicators to monitor and assess EH is fundamental in informing evidence-based interventions at the local level. A participatory approach to selecting indicators to inform the monitoring and assessment of EH in Lisbon is herein considered. Evidence derived from a systematic review of literature and data from Lisbon and Portuguese databases were analyzed by 12 Portuguese experts in individual semi-structured interviews. The interviews aimed at identifying relevant indicators and important emerging issues in the Lisbon urban setting. The outputs from the interviews were validated by a two-round Web-Delphi process in which panelists (22 experts) from different areas of expertise expressed their views regarding the relevance of the indicators for the analysis of EH in urban settings. Seventeen indicators were validated in the Web-Delphi process. High participation achieved along this process supports the view that this participatory approach was useful for validation. Results from the adopted participatory approach point out gaps in the collection of noise and mobility indicators data and raise emerging issues on housing indicators that require further research. The results also suggest the need for local action to improve indicators and tools in order to help the monitorization of EH in urban contexts. The adopted participatory approach can be replicated for other Portuguese and European urban settings.Marta Salgado research was supported by the Portuguese Foundation for Science and Technology (FCT) and Valorsul S.A. under the scholarship number PDE/BDE/120465/2016. Ana Vieira and Mónica Oliveira work were supported by the Portuguese Foundation for Science and Technology under the MEDI-VALUE project (Grant no. PTDC/EGE-OGE/29699/2017)info:eu-repo/semantics/publishedVersio

Salt-tolerant plants as sources of Antiparasitic Agents for human use: A comprehensive review

Parasitic diseases, especially those caused by protozoans and helminths, such as malaria, trypanosomiasis, leishmaniasis, Chagas disease, schistosomiasis, onchocerciasis, and lymphatic filariasis, are the cause of millions of morbidities and deaths every year, mainly in tropical regions. Nature has always provided valuable antiparasitic agents, and efforts targeting the identification of antiparasitic drugs from plants have mainly focused on glycophytes. However, salt-tolerant plants (halophytes) have lately attracted the interest of the scientific community due to their medicinal assets, which include antiparasitic properties. This review paper gathers the most relevant information on antiparasitic properties of halophyte plants, targeting human uses. It includes an introduction section containing a summary of some of the most pertinent characteristics of halophytes, followed by information regarding the ethnomedicinal uses of several species towards human parasitic diseases. Then, information is provided related to the antiprotozoal and anthelmintic properties of halophytes, determined by in vitro and in vivo methods, and with the bioactive metabolites that may be related to such properties. Finally, a conclusion section is presented, addressing perspectives for the sustainable exploitation of selected species.info:eu-repo/semantics/publishedVersio

Considering the stiffness of the forming tools in the numerical analysis of the ironing process

Ironing can occur in cylindrical cup drawing whenever the thickness of the drawn flange is larger than the gap between the punch and the die. This is particularly relevant for materials that present r-values lower than 1.0, such as the aluminium alloys, since they tend to present more thickening of the flange. The aim of this study is to evaluate numerically the impact of the elastic deformation of the forming tools on the final cup geometry, i.e., the earing profile and the evolution of thickness along the circumferential direction, at different heights. Different contact conditions are also analysed since they strongly affect both the thickness strain and the earing profile. The process conditions considered are the ones from EXACT, the ESAFORM Benchmark 2021, enabling the comparison with experimental results. Considering the deformation of the forming tools mainly impacts the ironing stage, enabling predicting wall thickness values larger than the gap between the punch and the die.The authors gratefully acknowledge the financial support of the Portuguese Foundation for Science and Technology (FCT) under projects with reference 2022.08459.PTDC, UIDB/00285/2020 and LA/P/0112/2020

Advancing diagnostics and disease modeling: current concepts in biofabrication of soft microfluidic systems

Soft microfluidic systems play a pivotal role in personalized medicine, particularly in in vitro diagnostics tools and disease modeling. These systems offer unprecedented precision and versatility, enabling the creation of intricate three-dimensional (3D) tissue models that can closely emulate both physiological and pathophysiological conditions. By leveraging innova- tive biomaterials and bioinks, soft microfluidic systems can circumvent the current limitations involving the use of polydi- methylsiloxane (PDMS), thus facilitating the development of customizable systems capable of sustaining the functions of encapsulated cells and mimicking complex biological microenvironments. The integration of lab-on-a-chip technologies with soft nanodevices further enhances disease models, paving the way for tailored therapeutic strategies. The current research concepts underscore the transformative potential of soft microfluidic systems, exemplified by recent breakthroughs in soft lithography and 3D (bio)printing. Novel applications, such as multi-layered tissues-on-chips and skin-on-a-chip devices, demonstrate significant advancements in disease modeling and personalized medicine. However, further exploration is warranted to address challenges in replicating intricate tissue structures while ensuring scalability and reproducibility. This exploration promises to drive innovation in biomedical research and healthcare, thus offering new insights and solutions to complex medical challenges and unmet needs.Â

On the effect of the ratio between the yield stresses in shear and in uniaxial tension on forming of isotropic materials

It is generally believed that the choice of the yield criterion used to describe the plastic behaviour of isotropic metallic materials does not affect much the accuracy of the predictions of forming operations. For this reason, the von Mises yield criterion is used for modelling the plastic behaviour. However, according to the von Mises yield criterion, irrespective of the material, the ratio between the yield stresses in simple shear and in uniaxial tension is the same. In this paper, it is presented a numerical study which reveals that even for one of the simplest deep drawing processes, namely the forming of a cylindrical cup, the yielding description influences the predictions of the plastic strains and the final profile of the part. For the description of yielding, an isotropic yield criterion which allows to differentiate between isotropic materials was used. Specifically, this yield criterion involves a parameter α which is expressible solely in terms of the ratio between the yield stresses in shear and in uniaxial tension; for α = 0 it reduces to the von Mises yield criterion. The results of the numerical study are revealing and are believed to provide a new point of view when considering material requirements for drawing performance and models to be used for prediction of the plastic behaviour in deep-drawing processes. From the analysis of the loading paths that the materials experience during the forming of the cup, it appears that the prevalent belief that the yielding properties in the tension-tension quadrant of the yield surface dictate the final profile should be reconsidered. Indeed, the simulations results indicate that for isotropic materials characterized by α > 0 (σT/τY> √ 3), the cup height is greater than for a von Mises material (α = 0), which is higher than the one obtained for materials with α < 0 (σT/τY< √ 3), i.e. lower values of the ratio between the yield stresses in shear and in uniaxial tension lead to greater cup heights. It is shown that this is mainly related to the plastic deformation of the material initially located in the flange region, which is dictated by the shape of the yield surface in the compression-tension quadrant (i.e. normal to the yield surface in the region between uniaxial compression and pure shear stress states).The authors gratefully acknowledge the financial support of the Portuguese Foundation for Science and Technology (FCT) under the projects with reference PTDC/EME-EME/30592/2017 (POCI01–0145-FEDER-030592) and PTDC/EME-EME/31243/2017 (POCI01–0145-FEDER-031243) and by UE/FEDER through the program COMPETE2020 under the project MATIS (CENTRO-01–0145-FEDER000014) and UIDB/00285/2020. JLA and NC gratefully acknowledge partial support for this work from the Air Force Research Laboratory (AFRL) under contract FA8651–08-D-0108/52

Environmental Turbulence, New Product Development and Innovation

This study aimed to implement a systematic review of literature, in order to find theoretical support on the relationship between new product development and product innovation, moderated by environmental turbulence in the technological and market dimensions. It was used the qualitative approach, with data and information collected from published articles on the subject. The criteria researched consisted of: temporal cut from 2000 to May 2015, the article must belong to the area of Business Management or Economy, to present relationship with Environmental Turbulence, Development of New Products and product innovation. In the literature used, it was not possible found any article presenting an integrative model using New Product Development or Product Innovation moderated by environmental turbulence in its two dimensions. Based on the review accomplished, it is possible to define more four subjects to be studied in future empirical works approach these elements