436 research outputs found

    Challenges for modern wine production in dry areas: dedicated indicators to preview wastewater flows

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    Wine production is an important socio-economic activity in Mediterranean countries. This study is focused on wine production under warm and dry climate conditions in south Portugal, in two major wine-producing regions (Tejo and Alentejo), characterized by small to medium sized wineries. Vineyards have been expanding in this region of Portugal, where about 50–70% of the vineyards are irrigated, increasing regional water demand. The aim of this study is to propose an integrative approach for wine production, where a simple calculation model has been developed and validated to preview water consumption and wastewater production, as functions of winemaking periods and type of processed grapes. Results revealed a global ratio of 2.2 ±0.45 and 2.1 ±0.17 Lwater/Lwine. Concerning dedicated indicators, 60–75% of the wastewater was produced during Period I and the red wine production represented a 50–64% increase in water consumption. This tool will enable winemakers to calculate Global and Dedicated Indicators, based on their own parameters, which provide information on flow volumes and peak flows. In this context, it will be possible to identify improvements for wastewater treatment and management towards water reuse as a promising solution for the wine sector in the framework of the circular economyinfo:eu-repo/semantics/publishedVersio

    Integrating human stem cell expansion and neuronal differentiation in bioreactors

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    <p>Abstract</p> <p>Background</p> <p>Human stem cells are cellular resources with outstanding potential for cell therapy. However, for the fulfillment of this application, major challenges remain to be met. Of paramount importance is the development of robust systems for <it>in vitro </it>stem cell expansion and differentiation. In this work, we successfully developed an efficient scalable bioprocess for the fast production of human neurons.</p> <p>Results</p> <p>The expansion of undifferentiated human embryonal carcinoma stem cells (NTera2/cl.D1 cell line) as 3D-aggregates was firstly optimized in spinner vessel. The media exchange operation mode with an inoculum concentration of 4 × 10<sup>5 </sup>cell/mL was the most efficient strategy tested, with a 4.6-fold increase in cell concentration achieved in 5 days. These results were validated in a bioreactor where similar profile and metabolic performance were obtained. Furthermore, characterization of the expanded population by immunofluorescence microscopy and flow cytometry showed that NT2 cells maintained their stem cell characteristics along the bioreactor culture time.</p> <p>Finally, the neuronal differentiation step was integrated in the bioreactor process, by addition of retinoic acid when cells were in the middle of the exponential phase. Neurosphere composition was monitored and neuronal differentiation efficiency evaluated along the culture time. The results show that, for bioreactor cultures, we were able to increase significantly the neuronal differentiation efficiency by 10-fold while reducing drastically, by 30%, the time required for the differentiation process.</p> <p>Conclusion</p> <p>The culture systems developed herein are robust and represent one-step-forward towards the development of integrated bioprocesses, bridging stem cell expansion and differentiation in fully controlled bioreactors.</p

    Discussing impact assessment on creative tourism: A theoretical and analytical model

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    Over the last decades, tourism has experienced exponential growth, expansion and diversification, being considered one of the most important socio-economic sectors, an essential source of income and employment for many territories (e.g. Bellini et al. 2017; Romão and Nijkamp 2017; Weidenfeld 2018). In response to the concerns about the negative impacts of tourism and to improve the relationship between hosts and tourists, culture-based creativity is seen as a path to create competitive advantages and improve more sustainable practices in the tourism field. Therefore, many cities and regions have sought to reinvent themselves as creative tourist destinations, by encouraging synergies between tourism and the cultural and creative activities to foster the development of new products, experiences and markets (Delisle and Jolin 2007; Duxbury and Richards 2019; Richards and Wilson 2007). Despite the high attractiveness of large capitals and metropolises, small towns and rural areas can also benefit from the growth of tourist flows and the demand for less overcrowded tourist destinations. Alternatively, they can offer interactive, small-scale, unique and tailor-made experiences based on local culture, lifestyles, and values thus generating potential positive impacts on these communities (Richards and Duif 2018; Wisansing and Vongvisitsin 2019). In the discussion of tourism development models, sustainability has become an unavoidable frame of reference, introducing cultural, social and environmental concerns, in addition to the analysis of economic issues. In this vein, we consider the integration of culture as a fundamental dimension of the analysis, together and in interrelation with the economic, social and environmental dimensions. Although the impact assessment exercises have focused on predominantly economic indicators, there is an increasing number of methods that can determine and monitor more accurately the multiple links and impacts of tourist activities in local communities, and also address sustainability issues. This paper has the objective of review the main theoretical and methodological approaches about impact assessment, to develop a comprehensive and operational framework capable of contributing to a better understanding the multifaced nature of creative tourism and their diverse impacts to support the formulation of policies for the sector and according to each context.FCT; FEDE

    Synthesis, structure and non-linear optical properties of L-argininium perrhenate crystal

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    A new hybrid organic–inorganic non-linear optical crystalline material, L-argininium perrhenate has been synthesized. The crystal belongs to P212121 space group, has a good optical quality and high transmission in the visible and near infra-red spectral regions. L-argininium perrhenate has high birefringence and is more than four times as efficient as KDP in second harmonic generation, making it a potentially attractive material for non-linear optical applicationsThis work was financially supported by the European Regional Development Fund (ERDF) through Programa Operacional Factores de Competitividade (COMPETE: FCOMP-01-0124-FEDER-014628) and the Portugal Fundacao para a Ciencia e Tecnologia (PTDC/CTM-NAN/114269/2009, PTDC/CTM/105597/2008 and Pest-C/FIS/UI0036/2011)

    Preparation of controlled release microspheres using supercritical fluid technology for delivery of anti-inflammatory drugs

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    Ethylcellulose/methylcellulose blends were produced using different precipitation techniques and impregnated with naproxen, a non-steroidal anti-inflammatory drug (NSAID). Solvent-evaporation technique was used not only for the preparation of ethylcellulose/methylcellulose microspheres but also to encapsulate naproxen. Supercritical fluid (SCF) impregnation was also performed to prepare naproxen loaded microspheres. The microspheres, impregnated by the SCF technique, were prepared both by solvent-evaporation and by a supercritical antisolvent (SAS) process. In vitro release profiles at pH 7.4 and 1.2, of naproxen-loaded microspheres were evaluated and the results were modelled Fick’s law of diffusion and Power law. Miscrospheres prepared by supercritical antisolvent have a higher loading capacity and present a slower release profile. The systems studied present a release mechanism controlled by drug diffusion which complies Fick’s law of diffusion

    Agro-food byproducts as a new source of natural food additives

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    Nowadays, the agro-food industry generates high amounts of byproducts that may possess added value compounds with high functionality and/or bioactivity. Additionally, consumers' demand for healthier foodstuffs has increased over the last years, and thus the food industry has strived to answer this challenge. Byproducts are generally secondary products derived from primary agro-food production processes and represent an interesting and cheaper source of potentially functional ingredients, such as peptides, carotenoids, and phenolic compounds, thus promoting a circular economy concept. The existing body of work has shown that byproducts and their extracts may be successfully incorporated into foodstuffs, for instance, phenolic compounds from eggplant can be potentially used as a mulfitunctional food additive with antimicrobial, antioxidant, and food colorant properties. As such, the aim of this review is to provide insights into byproducts and their potential as new sources of foodstuffs additives.info:eu-repo/semantics/publishedVersio

    Personalized Recommendation of PoIs to People with Autism

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    The suggestion of Points of Interest to people with Autism Spectrum Disorder (ASD) challenges recommender systems research because these users' perception of places is influenced by idiosyncratic sensory aversions which can mine their experience by causing stress and anxiety. Therefore, managing individual preferences is not enough to provide these people with suitable recommendations. In order to address this issue, we propose a Top-N recommendation model that combines the user's idiosyncratic aversions with her/his preferences in a personalized way to suggest the most compatible and likable Points of Interest for her/him. We are interested in finding a user-specific balance of compatibility and interest within a recommendation model that integrates heterogeneous evaluation criteria to appropriately take these aspects into account. We tested our model on both ASD and "neurotypical" people. The evaluation results show that, on both groups, our model outperforms in accuracy and ranking capability the recommender systems based on item compatibility, on user preferences, or which integrate these two aspects by means of a uniform evaluation model

    Recycling of cellulases in lignocellulosic hydrolysates using alkaline elution

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    The recovery of cellulases from lignin, lignocellulosic hydrolysates and cellulose by alkaline washes at pH 9 and 10 was examined. The effect of the pH on the structural stability of purified Cel7A was analyzed by circular dichroism. Purified Cel7A showed conformational changes at pH 9 and 10 that were reversible at pH 4.8. Temperature influenced the enzymatic hydrolysis of wheat straw and may be critical for the efficiency of cellulase recycling from wheat straw hydrolysates. Operation at moderate temperatures (37 °C) resulted in a rate of saccharification 19% higher than that obtained at 50° C, improving cellulase recycling by 49%. Over 60% of the enzyme activity on the synthetic substrate 4-methylumbelliferyl-β-d-cellobioside (MUC) may be recovered by using a simple alkaline wash. This is thus a promising strategy for enzyme recycling that is simple to implement at industrial scale, economical and effective.The authors acknowledge funding through FP7 KACELLE (Kalundborg Cellulosic Ethanol) project for supporting his work. We also thank Dr. Mai Ostergaard Haven for critical reviewing of the manuscript and Dr. Jane Lindedam for supplying the lignin

    How does dilution affect the conductivity, the propensity to aggregate and the biological activity of enzymes?

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    The current theories do not provide a convincing explanation for many of the protein' manifestations in solution. Therefore, to shed some light on this critical question, the present work analyzed the effect of dilution on the ability of proteins to catalyze chemical reactions, the so-called biological activity. As models enzymes, laccase from Trametes versicolor and chicken egg white lysozyme were used. The results show that the enzymes' specific biological activity increases on dilution. Three explanations for the intriguing observation were advanced and submitted to experimental scrutiny. Amongst the three hypotheses, only one was corroborated by experiments. According to this explanation, when dissolved in water, proteins reveal two populations: one biologically active whose relative occurrence increases on dilution and another which is not active and whose molecular proportion varies in the opposite direction. Therefore, the reported experimental facts strongly support the chemical behaviour of the proteins in the solution. According to the herein-advocated concepts, they could undergo a dissociation process similar to that found in electrolyte chemistry.publishe
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