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- HomeTree: an art inspired mobile eco-feedback visualizationPublication . Quintal, Filipe; Nisi, Valentina; Nunes, Nuno; Barreto, Mary; Pereira, LucasThis paper presents HomeTree a prototype of an art-inspired mobile eco feedback system. The system is implemented on a tablet PC and relies on a non intrusive energy-monitoring infrastructure to access consumption and power event information. Our prototype addresses an important problem in eco feedback, which is the fact that users loose interest about their energy consump tion after a period of several weeks. To accomplish this HomeTree implements a dual visualization strategy. Initially HomeTree presents users with a screensa ver that shows energy consumption mapped in a dynamic illustration of the lo cal forest. Through this strategy we leverage the emotional connection between the short-term energy consumption and the long-term effects on nature through the local depicted landscape. In a second mode of operation users can interact with HomeTree directly by checking the historical records of their consumption data, and check which days or weeks they have reduced or increased consump tion. Furthermore a comparison with a more objective baseline, such as the city of Funchal energy consumption is provided, in order to give users a sense of the level of their consumption in a wider context.
- Review of sewage sludge as a soil amendment in relation to current international guidelines: a heavy metal perspectivePublication . Nunes, Nuno; Ragonezi, Carla; Gouveia, Carla S. S.; Carvalho, Miguel Â. A. Pinheiro deOverexploitation of resources makes the reutilization of waste a focal topic of modern society, and the question of the kind of wastes that can be used is continuously raised. Sewage sludge (SS) is derived from the wastewater treatment plants, considered important underused biomass, and can be used as a biofertilizer when properly stabilized due to the high content of inorganic matter, nitrate, and phosphorus. However, a wide range of pollutants can be present in these biosolids, limiting or prohibiting their use as biofertilizer, depending on the type and origin of industrial waste and household products. Long-term applications of these biosolids could substantially increase the concentration of contaminants, causing detrimental effects on the environment and induce hyper accumulation or phytotoxicity in the produced crops. In this work, some critical parameters for soils and SS agronomic use, such as organic matter, nitrogen, phosphorous, and potassium (NPK), and heavy metals concentration have been reviewed. Several cases of food crop production and the accumulation of heavy metals after SS application are also discussed. SS production, usage, and legis lation in EU are assessed to determine the possibility of sustainable management of this bioresource. Additionally, the World Health Organization (WHO) and Food and Agriculture Organization (FAO) guidelines are addressed. The opportunity to produce bioenergy crops, employing sewage sludge to enhance degraded land, is also considered, due to energy security. Although there are numerous advantages of sewage sludge, proper screening for heavy metals in all the variants (biosolids, soil, food products) is a must. SS application requires appropriate strict guidelines with appropriate regulatory oversight to control contamination of agricultural soils.
- Constructing ethanol-derived bioactive extracts using the brown seaweed Zonaria tournefortii (J.V.Lamouroux) Montagne performed with Timatic extractor by means of response surface methodology (RSM)Publication . Nunes, N.; Valente, S.; Ferraz, S.; Barreto, Maria Carmo; Carvalho, M.A.A. Pinheiro deUnderstanding the biochemical and antioxidant composition and capacity of a target biomass is the first step to its selectivity as functional food which can enhance the ability to promote health by reducing the risk of chronic diseases. The main purpose of this work was to employ response surface methodology (RSM) to determine the effect of the independent variables, % of ethanol (50–96%), time of sonication (0–20 min), and number of extraction cycles (6–18 cycles) in the primary extract of brown seaweed Zonaria tournefortii, studying the yield variation of some bioactive compounds, assessing the potential of these bioextracts to integrate as a natural additives or supplements in the functional food industry. The extractions were performed employing “Green Chemistry” techniques executed with the Timatic extractor, which applied pressurized ethanol solution at a maximum pressure of 8.5 bar through milled dehydrated biomass in the extraction vessel. Several parameters were assessed in the primary bioactive extract which included extract yield (11.56–28.49 g (100 g)−1 dw), total chlorophyll content (0.14–1.42 g (100 g)−1 dw), total carotenoid content (0.35–0.80 g (100 g)−1 dw), total fucoxanthin content (0.04–0.13 g (100 g)−1 dw), total phenolic content (3.58–5.84 g (100 g)−1 dw), total flavonoid content (0.22–4.70 g (100 g)−1 dw), DPPH (56.05–76.45%), and reducing activity (3.83–6.04 g (100 g)−1 dw). A second objective was to determine the suitability of the residue for subsequent extraction of valuable compounds such as fucoidan (4.87 to 6.59 g (100 g)−1 dw) and cellulose (18.88 to 20.27 g (100 g)−1 dw), implementing the first step to a biorefinery strategy, using a cascade approach.
- Different seaweeds use for iodine deficiency overcomePublication . Ferraz, Sónia; Ragonezi, Carla; Nunes, Nuno; Valente, Sofia; Carvalho, Miguel A. A. Pinheiro deIodine deficiency is one of the three most common nutritional deficiencies worldwide and is a global public health problem that affects particularly the young children, pregnant women and elderly. The consequences of iodine deficiency disorder (IDD) include goiter and cretinism. The traditional consumption of iodine via supplemented salt should be monitored to reduce population sodium intake due to hypertension problems and the uncertain bioavailability of iodine in the supplemented salt. One approach for an effective and cost-efficient iodine supplementation is the use of seaweeds in food intake. Seaweeds, among all foods, are the most famous and reliable source of natural iodine. In this minireview we pretend to explore the different uses of seaweeds to fill the iodine deficiency and improve life quality.
- Nutraceutical potential of Asparagopsis taxiformis (Delile) Trevisan extracts and assessment of a downstream purification strategyPublication . Nunes, N.; Valente, S.; Ferraz, S.; Barreto, Maria Carmo; Carvalho, M. A. A. Pinheiro deThe main goal of the present work was to determine the nutraceutical potential of Asparagopsis taxiformis D. extracts from Madeira Archipelago south coast. Extraction methodologies consisted either/or in 72 hours stirring, at room temperature (M1), or 6 cycles of Soxhlet extraction (M2), both with re-extraction. Solvents used were distilled water, ethanol, methanol and ethyl acetate. M1 allowed to obtain the highest values for extraction yield (31.65 g.100g 1 dw) using water, whereas iodine content (3.37 g.100g 1 dw), TPC (1.71 g GAE.100g 1 dw) and chlorophyll a (45.96 mg.100g 1 dw) were obtained using ethanol, and TCC (36.23 mg.100g 1 dw) with methanol. Extracts that showed higher reduction activity in M1 were derived from ethanol extraction (1,908 mg AAE.100g 1 dw). Water and ethanol were the best solvents for higher DPPH scavenging activity in M2, both with same result (IC50 1.37 mg.mL 1 ). The lowest value of IC50 for chelating activity (1.57 mg.mL 1 ) was determined in M1, using ethyl acetate. The remaining residue was used to obtain other products, i.e. lipid extraction (M1, 2.05 g.100g 1 dw), carrageenans (M2, 21.18 g.100g 1 dw) and cellulose (M1, 23.81 g.100g 1 dw) with subsequent FTIR ATR analysis. Our results show that A. taxiformis is a valuable source of bioactive compounds. The M1 extraction methodology using ethanol is the most effective solvent to produce an iodine rich bioactive extract with potential of being used as a nutraceutical supplement. Also, we have demonstrated a possible downstream strategy that could be implemented for multiple compound extraction from A. taxiformis residue. This has a vital importance for future feasibility, when using this biomass as an industrial feedstock for multiple products production. Statistical analysis, using SPSS 24.0, was also performed and important correlations were found between assays and methods.
- Why don't families get along with eco-feedback technologies?Publication . Barreto, Mary; Karapanos, Evangelos; Nunes, NunoEco-feedback domestic technologies have gained momentum over the last decade. Yet, while a wide range of research prototypes and commercial products has been proposed, their acceptance by families is still limited. In this paper we report on our findings from interviews with 15 dual income families, during a year-long deployment of an eco-feedback technology that attempted to inquire into the factors that prohibited its adoption. We found the non adoption of our system to be rooted in a number of systemic failures, relating to the physical context, the families’ social dynamics and the roles assumed by family members, as well as families’ priorities and the non-negotiability of their routines. Motivated by prior work and our empirical findings we propose three distinct dimensions but also phases in the adoption of eco-feedback technologies: orientation, incorporation and social integration, and discuss how these may hint at different barriers in the adoption of eco-feedback technologies.
- Evaluation of fucoxanthin contents in seaweed biomass by vortex-assisted solid-liquid microextraction using high-performance liquid chromatography with photodiode array detectionPublication . Nunes, N.; Leça, João M.; Pereira, Ana C.; Pereira, Vanda; Ferraz, S.; Barreto, Maria Carmo; Marques, José C.; Carvalho, M.A.A. Pinheiro deFucoxanthin is considered an important marine bioactive compound with biological properties with promising effects, namely on health. A simple and efficient analytical methodology is proposed for its quantification in seaweed biomass by using vortex-assisted solid-liquid microextraction (VASLME) followed by reversed phase high-performance liquid chromatography (RP-HPLC) photodiode array detection (PDA) analysis. This microextraction uses reduced quantities of sample (25 mg) and solvent (300 μL of ethanol) to efficiently extract this high-valued xanthophyll, in a vortex time of 15 min. These extraction parameters were optimized performing a Central Composite Design (CCD) analysis, running 32 individual experiments. In turn, the method validation was assessed. The linearity of the method was confirmed (R2 = 0.99998) in a concentration range from 12 to 3600 μg·g−1 dw. Also, good sensitivity and accuracy results were observed through the LOD (3.33 μg·g−1 ), LOQ (10.09 μg·g−1 ) and recovery (varied from 95 to 97%) assessments. Good precision was also verified, with intra-day variation within 2.0–3.3%, and inter-day within 1.0–3.8%. Matrix effect was also evaluated and an acceptable variation of 3.4% was found. The method applicability was confirmed by the analysis of 22 seaweed biomass samples and fucoxanthin content was found to vary from about 10 to 853 μg·g−1 dw. This method demonstrated a good performance and can be successfully implemented for a rapid, reliable and accurate screening of fucoxanthin in seaweed biomass.
- Evaluation of the use of marine macroalgae in the industrial production of biorefinery-derived biofunctional productsPublication . Nunes, Nuno Miguel Velosa; Carvalho, Miguel Ângelo Almeida Pinheiro de; Barreto, Maria do Carmo Roque Lino FelgueirasA tese de doutoramento aqui apresentada integra a avaliação da composição bioquímica de várias espécies de macroalgas, prospetadas no arquipélago da Madeira e arrojamentos de macroalgas provenientes de Gran Canária com o objetivo principal de determinar a potencialidade destes recursos em integrar estratégias de biorefinaria. Esta metodologia é extremamente importante para a gestão sustentável de recursos e mitigação dos impactos, promovidos pela indústria tradicional e pela exploração intensiva dos recursos naturais, desenvolvendo modelos dinâmicos, lucrativos e confiáveis. Este trabalho está dividido em três capítulos, integrando uma introdução geral, um capítulo composto por artigos científicos e um terceiro capítulo que incorpora uma discussão, conclusão e perspetivas futuras. O capítulo 2 começa por abordar uma análise morfológica em 3 macroalgas, por forma a compreender o seu ciclo biológico. Integra 2 artigos que descrevem a variabilidade bioquímica, nutricional e antioxidante e adicionalmente outros 2 artigos que abordam a avaliação da quantidade de iodo e fucoxantina com precisão, biocompostos de extrema importância económica e nutracêutica, no qual foram desenvolvidas e validadas novas metodologias analíticas para uma rápida análise destes compostos nesta biomassa. A implementação de estratégias de biorefinaria foram conduzidas em 2 macroalgas, A. taxiformis e Z. tournefortii. Na primeira foram utilizados 4 solventes e 2 metodologias para a extração primária de um composto bioativo, efetuando posteriormente a extração sequencial de lípidos, carragenanas e celulose do resíduo remanescente. Para a segunda, foi utilizado 1 solvente, utilizando o extrator Timatic em conjunto com um modelo estatístico por forma a modelar e otimizar a extração de um composto bioativo, extraindo subsequente do resíduo fucoidano e celulose. Adicionalmente, foi efetuada a avaliação da composição dos ácidos gordos em 3 macroalgas coletadas no arquipélago da Madeira, efetuado uma avaliação por TLC, ATR-FTIR, atividade anticolinesterásica e citotoxicidade in vitro na linhagem de células tumorais A549.
- Avaliação e valorização de recursos agrícolas: avaliação nutricional e mineral de variedades tradicionais de batata-doce (Ipomoea batatas L.) provenientes da Madeira e AçoresPublication . Nunes, Nuno Miguel Velosa; Carvalho, Miguel Ângelo Almeida Pinheiro deEste trabalho foi desenvolvido com o intuito de avaliar nutricionalmente variedades agrícolas regionais madeirenses e açorianas de Ipomoea batatas L. (batata-doce). No total 18 amostras foram analisadas, entre as quais 11 são variedades provindas da Madeira e outras 7 provindas dos Açores. O maior objectivo deste estudo foi comparar a composição nutricional e mineral de um conjunto de variedades de batata-doce, valorizando assim os recursos agrícolas da Madeira e Açores. A caracterização nutricional e mineral dos rizomas, produzidos nestas regiões, proporcionou informação relevante para a valorização destes recursos. Sendo um rizoma tropical consumido habitualmente pela população e disponível todo o ano, torna essencial a sua avaliação. A análise laboratorial dos rizomas permitiu determinar um conjunto de características nutricionais. De um modo geral, os valores nutricionais médios detectados em rizomas de batata-doce destas duas regiões são de 93,64 g/100g de MS para o resíduo seco, 3,01 g/100g de MS para cinzas, 3,19 g/100g de MS para fibra (ADF), 1,21 g/100g de MS para gordura bruta, 3,20 g/100g de MS para proteína, 14,00 g/100g de MS para açúcares solúveis e 59,72 g/100g de MS para o amido. A análise mineral incluiu a determinação de fósforo, potássio, cálcio, magnésio, ferro, cobre, zinco, manganês e boro. Na variedade “De cenoura” (ISOP 1028), foi quantificado o nível de pro-vitamina A pela técnica de HPLC, que foi verificado ser 12,48 mg/100g em MS de β-caroteno. Os dados obtidos na análise nutricional foram usados para construir uma base de dados no NIRS (Near Infra-Red Spectroscopy) de modo a construir um modelo de previsão que possa predizer o valor nutritivo de um grande número de amostras em tempo reduzido, com um mínimo de impacto ambiental. Posteriormente, os dados obtidos através das análises nutricionais e minerais foram introduzidos no software estatístico SPSS 19.0 para determinar correlações e similaridades.
- Understanding families’ motivations for sustainable behaviorsPublication . Barreto, Mary L.; Szóstek, Agnieszka; Karapanos, Evangelos; Nunes, Nuno J.; Pereira, Lucas; Quintal, FilipeWhile interest in eco-feedback technologies has peaked over the last decade, research increasingly high lights that simply providing information to individuals regarding their consumption behaviors does not guarantee behavior change. This has lead to an increasing body of work that attempts to characterize individuals’ latent motivations that drive sustainable behaviors. With this paper we aim at expanding this body of work by analyzing such motivations in the context of families. We report findings from inter views with 15 families who used an eco-feedback interface over a period of 2 years. Our study reveals that motivations for sustainable behavior were not only rooted in individuals’ environmental concerns and need for expense management but they also regarded: (i) individuals’ and families’ need for a sense of control and security, (ii) parents’ self-perceived responsibility of their role as parents and (iii) the percep tion of individual as well as family identity. We argue that in order for eco-feedback technologies to attain long-lasting behavioral changes in the domestic environment they need to address basic family needs that go beyond individual ideals of pro-environmental behavior
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