260 research outputs found

    Análise do impacto do processo organosolv para pré-tratamento de biomassa lenhocelulósica na redução das emissões de gases com efeito de estufa (GEE)

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    CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: No âmbito do projeto H2020 AMBITION, foram desenvolvidos processos de pré-tratamento inovadores e energeticamente eficientes, a fim de serem integrados num conceito de melhoria do processamento da biomassa para a produção de correntes líquidas de açúcares e derivados de lenhina para aplicações em bioenergia e produtos de valor acrescentado. O objetivo deste trabalho consiste em analisar os impactos ambientais do pré-tratamento organosolv de biomassa (palha de trigo e resíduos de eucalipto) utilizando misturas etanol/água, a fim de avaliar a sua integração num processo multiproduto de modo a originar elevados rendimentos de açúcares e recuperar lenhina de alta qualidade num conceito de biorrefinaria. O processo foi simulado em SuperPro Designer (Intelligen Inc.) para determinar os balanços de massa e energia, bem como para desenvolver o Inventário de Ciclo de Vida (LCI). A Avaliação do Ciclo de Vida (ACV) foi realizada utilizando o software SimaPro 9.0 (PRé Consultants BV) com a base de dados Ecoinvent 3.5, sendo comparada com os processos clássicos de pré-tratamento à escala industrial (e.g. explosão com vapor). O processo organosolv com etanol e para uma razão líquido-sólido (RLS) padrão de 10, apresenta resultados em termos de emissões de GEE (numa abordagem gate-to-gate) ligeiramente superiores aos obtidos para a explosão com vapor, concluindo-se posteriormente que na tecnologia organosolv, só a redução da RLS pode conduzir a melhorias significativas em termos ambientais.ABSTRACT: Within the H2020 AMBITION project, innovative and energy efficient pre-treatment processes were developed in order to be integrated in a biomass processing improvement concept that would produce liquid streams of sugars and lignin derivatives for applications in bioenergy and added-value products. The objective of this work is to analyse the environmental impacts of organosolv pre-treatment of biomass (wheat straw and eucalyptus residues) using ethanol/water mixtures in order to assess its integration in a multi-product process to produce high sugar yields and recover high quality lignin in a biorefinery concept. The process was modelled in SuperPro Designer (Intelligen Inc.) to determine mass and energy balances as well as to develop the Life Cycle Inventory (LCI). The Life Cycle Assessment (LCA) was performed using SimaPro 9.0 software (PRé Consultants BV) with the Ecoinvent 3.5 database and compared with classical industrial scale pre-treatment processes (e.g. steam explosion). The organosolv process with ethanol with a standard liquid-to-solid ratio (LSR) of 10, presents, in terms of GHG emissions (in a gate-to-gate approach), slightly higher GHG emissions than those obtained for the steam explosion, leading to the conclusion that a reduction in the solid-liquid ratio in organosolv technology causes significant environmental improvements.info:eu-repo/semantics/publishedVersio

    Angiopoietin-2 Promotes Inflammatory Activation in Monocytes of Systemic Sclerosis Patients

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    Angiopoietin-2 (Ang-2), a ligand of the tyrosine kinase receptor Tie2, is essential for vascular development and blood vessel stability and is also involved in monocyte activation. Here, we examined the role of Ang-2 on monocyte activation in patients with systemic sclerosis (SSc). Ang-2 levels were measured in serum and skin of healthy controls (HCs) and SSc patients by ELISA and array profiling, respectively. mRNA expression of ANG2 was analyzed in monocytes, dermal fibroblasts, and human pulmonary arterial endothelial cells (HPAECs) by quantitative PCR. Monocytes were stimulated with Ang-2, or with serum from SSc patients in the presence of a Tie2 inhibitor or an anti-Ang2 neutralizing antibody. Interleukin (IL)-6 and IL-8 production was analyzed by ELISA. Ang-2 levels were elevated in the serum and skin of SSc patients compared to HCs. Importantly, serum Ang-2 levels correlated with clinical disease parameters, such as skin involvement. Lipopolysaccharide (LPS) LPS, R848, and interferon alpha2a (IFN-alpha) stimulation up-regulated the mRNA expression of ANG2 in monocytes, dermal fibroblasts, and HPAECs. Finally, Ang-2 induced the production of IL-6 and IL-8 in monocytes of SSc patients, while the inhibition of Tie2 or the neutralization of Ang-2 reduced the production of both cytokines in HC monocytes stimulated with the serum of SSc patients. Therefore, Ang-2 induces inflammatory activation of SSc monocytes and neutralization of Ang-2 might be a promising therapeutic target in the treatment of SSc

    The Secretome Derived From 3D-Cultured Umbilical Cord Tissue MSCs Counteracts Manifestations Typifying Rheumatoid Arthritis

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    Rheumatoid arthritis (RA) is an autoimmune disorder whose treatment is mostly restricted to pain and symptom management and to the delay of joint destruction. Mesenchymal stem/stromal cells from the umbilical cord tissue (UC-MSCs) have previously been proven to be immunomodulatory and more efficient than bone marrow-derived MSCs in causing remission of local and systemic arthritic manifestations in vivo. Given the paracrine nature of UC-MSC activity, their application as active substances can be replaced by their secretome, thus avoiding allogeneic rejection and safety issues related to unwanted grafting. In this work, we aimed at demonstrating the viability of applying the 3D-primed UC-MSC secretome for the amelioration of arthritic signs. A proteomic analysis was performed to both, media conditioned by UC-MSC monolayer (CM2D) and 3D cultures (CM3D). The analysis of relevant trophic factors confirmed secretome profiles with very significant differences in terms of therapeutic potential. Whereas, CM3D was characterised by a prevailing expression of anti-inflammatory cytokines such as IL-10 and LIF, along with trophic factors involved in different mechanisms leading to tissue regeneration, such as PDGF-BB, FGF-2, I-309, SCF, and GM-CSF; CM2D presented relatively higher levels of IL-6, MCP-1, and IL-21, with recognised pro-inflammatory roles in joint disease and pleiotropic effects in the progression of rheumatoid arthritis (RA). Accordingly, different motogenic effects over mouse chondrocytes and distinct capacities of inducing glycosaminoglycan synthesis in vitro were observed between CM3D and CM2D. Finally, the evaluation of arthritic manifestations in vivo, using an adjuvant-induced model for arthritis (AIA), suggested a significantly higher therapeutic potential of CM3D over CM2D and even UC-MSCs. Histological analysis confirmed a faster remission of local and systemic arthritic manifestations of CM3D-treated animals. Overall, the results show that the use of UC-MSC CM3D is a viable and better strategy than direct UC-MSC administration for counteracting AIA-related signs. This strategy represents a novel MSC-based but nonetheless cell-free treatment for arthritic conditions such as those characterising RA

    Corrigendum: Delivery of crop pollination services is an insufficient argument for wild pollinator conservation

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    There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation. However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery is restricted to a limited subset of all known bee species. Across crops, years and biogeographical regions, crop-visiting wild bee communities are dominated by a small number of common species, and threatened species are rarely observed on crops. Dominant crop pollinators persist under agricultural expansion and many are easily enhanced by simple conservation measures, suggesting that cost-effective management strategies to promote crop pollination should target a different set of species than management strategies to promote threatened bees. Conserving the biological diversity of bees therefore requires more than just ecosystem-service-based arguments

    Chromium(III) biosorption onto spent grains residual from brewing industry : equilibrium, kinetics and column studies

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    The use of industrial wastes for wastewater treatment as a strategy to their re-use and valorisation may provide important advances toward sustainability. The present work gives new insights into heavy metal biosorption onto low-cost biosorbents, studying chromium(III) biosorption onto spent grains residual from a Portuguese brewing industry both in batch and expanded bed column systems. Experimental studies involved unmodified spent grains and spent grains treated with NaOH. Metal uptake followed a rapid initial step, well described by the pseudo-second-order kinetic model up to 27 h, indicating chemisorption to be the rate-limiting step. Beyond this period intraparticle diffusion assumed an important role in the uptake global kinetics. The best fit for equilibrium data was obtained using the Langmuir model, with unmodified spent grains having the higher maximum uptake capacity (q max = 16.7 mg g1). In open system studies, using expanded bed columns, the best performance was also achieved with unmodified spent grains: Breakthrough time (C/C i = 0.25) and total saturation time (C/C i = 0.99) occurred after 58 and 199 h of operation, corresponding to the accumulation of 390 mg of chromium(III), 43.3 % of the total amount entering the column. These results suggest that alkali treatment does not improve spent grains uptake performance. Changes in biomass composition determined by Fourier transform infrared spectroscopy suggested hydroxyl groups and proteins to have an important role in chromium(III) biosorption. This study points out that unmodified spent grains can be successfully used as low-cost biosorbent for trivalent chromium.The authors would like to thank the Portuguese brewing industry UNICER for all the support and FCT (Fundacao para a Ciencia e a Tecnologia) financial support through the Grant PRAXIS XXI/BD/15945/98
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