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- Proof-of-Principle That Cellular Automata Can Be Used to Predict Infestation Risk by Reticulitermes grassei (Blattodea: Isoptera)Publication . Sequeira, João G. N.; Nobre, Tânia; Duarte, Sónia; Jones, Dennis; Esteves, Bruno; Nunes, LinaOver the past few decades, species distribution modelling has been increasingly used to monitor invasive species. Studies herein propose to use Cellular Automata (CA), not only to model the distribution of a potentially invasive species but also to infer the potential of the method in risk prediction of Reticulitermes grassei infestation. The test area was mainland Portugal, for which an available presence-only dataset was used. This is a typical dataset type, resulting from either distribution studies or infestation reports. Subterranean termite urban distributions in Portugal from 1970 to 2001 were simulated, and the results were compared with known records from both 2001 (the publication date of the distribution models for R. grassei in Portugal) and 2020. The reported model was able to predict the widespread presence of R. grassei, showing its potential as a viable prediction tool for R. grassei infestation risk in wooden structures, providing the collection of appropriate variables. Such a robust simulation tool can prove to be highly valuable in the decisionmaking process concerning pest management.
- Enhancing Liquefaction Efficiency: Exploring the Impact of Pre-Hydrolysis on Hazelnut Shell (Corylus avellana L.)Publication . Cruz-Lopes, Luísa; Duarte, Joana; Dulyanska, Yuliya; Guiné, Raquel; Esteves, BrunoHazelnut shells (HS), scientifically known as Corylus avellana L. shells, are waste produced by companies that process nuts. The main objective of this study was to find an efficient way to maximize the chemical potential of HS by solubilizing the hemicelluloses, which could then be used to recover sugars and, at the same time, increase the lignin content of this material to produce adhesives or high-strength foams. In order to optimize the pre-hydrolysis process, two different temperatures (160 and 170 °C) and times varying from 15 to 180 min were tested. All the remaining solid materials were then liquefied using polyalcohols with acid catalysis. The chemical composition of hazelnut shells was determined before and after the pre-hydrolysis. All of the process was monitored using Fourier Transform Infrared Spectroscopy with Attenuated Total Reflectance (FTIR-ATR) by determining the spectra of solids and liquids after the pre-hydrolysis and liquefaction steps. The highest solubilization of hazelnut shells was found for 170 °C and 180 min, resulting in a 25.8% solubilization. Chemical analysis after the hydrolysis process showed a gradual increase in the solubilization of hemicelluloses as both the temperature and time of the reactor were increased. Simultaneously, the percentages of α-cellulose and lignin in the material also increased with rises in temperature and duration. FTIR-ATR allowed for the detection of significant spectral changes in the hazelnut shells from their initial state to the solid residue and further into the liquefied phase. This confirmed that pre-hydrolysis was effective in enhancing the chemical composition of the material, making it more suitable for the production of adhesives, polyurethane foams, or in the production of bioplastics and composite materials, combined with other biopolymers or synthetic polymers to enhance the mechanical properties and biodegradability of the resulting materials.
- Edible Insects: Perceptions of Marketing, Economic, and Social Aspects among Citizens of Different CountriesPublication . Guiné, Raquel; Florença, Sofia De Guiné E; Costa, Cristina Amaro Da; Correia, Paula; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, Manuela; Fragata, Anabela; Cardoso, Ana Paula; Campos, Sofia; Anjos, Ofélia; Bartkiene, Elena; Djekic, Ilija; Matran, Irina M.; Čulin, Jelena; Klava, Dace; Chuck-Hernández, Cristina; Korzeniowska, Malgorzata; Boustani, Nada M.; Papageorgiou, Maria; Gutiérrez, Bernardo Prieto; Černelič-Bizjak, Maša; Damarli, Emel; Ferreira, VanessaBecause edible insects (EI) have been, in recent years, recommended as a nutritious animal protein food with enormous environmental advantages over other sources of animal protein for human consumption, studies aimed at investigating the consumer perspective have become more prominent. Hence, this study intended to examine the perceptions of participants from different countries about the commercialization and economic and social impacts of edible insects. The study was made using a questionnaire survey, and data were collected in Brazil, Croatia, Greece, Latvia, Lebanon, Lithuania, Mexico, Poland, Portugal, Romania, Serbia, Slovenia, Spain, and Turkey. The final number of received answers was 7222 participants. For the treatment of the results, different statistical techniques were used: factor analysis, internal reliability by Cronbach’s alpha, cluster analysis, ANOVA to test differences between groups, and Chi-square tests. The results obtained confirmed the validity of the scale, constituted by 12 out of the 14 items initially considered, distributed by 4 factors: the first related to the economic impact of EIs, the second related to the motivation for consumption of EIs, the third related to the places of purchase of EIs, and the fourth corresponding to a question presented to the participants as a false statement. A cluster analysis allowed identifying three clusters, with significant differences between them according to all the sociodemographic variables tested. Also, it was found that the participants expressed an exceptionally high level of agreement with aspects such as the difficulty in finding EIs on sale, knowledge acting as a strong motivator for EI consumption, and the role of personalities and influencers in increasing the will to consume EIs. Finally, practically all sociodemographic variables were found to be significantly associated with perceptions (country, sex, education, living environment, and income), but not age. In conclusion, the perceptions about EI commercialization were investigated and revealed differences among samples originating from different countries. Moreover, the sociodemographic characteristics of the participants were found to be strongly associated with their perceptions.
- Determination of some wood properties and response to weathering of Citrus limon (L.) Burm woodPublication . Şahin, Sırrı; Ayata, Umit; Bal, Bekir Cihad; Esteves, Bruno; Can, Ahmet; Sivrikaya, HüseyinOrange is a fruit of the Citrus genus in the family Rutaceae. It is assumed to have originated in southern Asia, and to have been first cultivated in China around 2500 BC. There is little knowledge on the quality of wood from orange trees, which is occasionally used in fine woodwork, tool handles, mosaics, and marquetry. This work aimed to evaluate the possibility of using orange wood from agricultural conversions and orchard plantation renewals to make products with a high value. Logs from plantations located in southern Italy were collected, and the key aspects for determining the suitability of using the wood as flooring were examined. Laboratory tests were carried out to determine the shrinkage, dimensional stability, and surface hardness, which included an indentation test on the wood flooring. Drying trials were also performed, and prototypes of flooring were prepared so professionals and end users could evaluate the aesthetic value. The results confirmed that the wood from orange trees is fine-grained, and is characterized by a high density and shrinkage, average dimensional stability, and high surface hardness. The results of the tests suggested performing careful drying and following specific procedures according to the size of the elements. The wood was highly appreciated by the users, which confirmed the possibility of using this wood as a renewable raw material, despite the limited availability, for manufacturing high-quality products.
- Agro-industrial wastes as building insulation materials: A review and challenges for Euro-Mediterranean countriesPublication . Cintura, Eleonora; Nunes, Lina; Esteves, Bruno; Faria, PaulinaThis study investigates the possibility of using agro-industrial wastes for building products, mainly focusing on their insulation properties. A classification of bio-wastes is provided, namely of the lignocellulosic ones and their features and properties are described. Information about three main topics is collected: world production and consumption of some crops already used as building materials, their chemical composition and their most studied properties. Since the considered materials are lignocellulosic and they have many common features, a com- parison is made. The aim is to have comparable information to support future research related to the production of eco-efficient indoor insulation boards. The result of this research is the choice of four different agro-industrial wastes produced in the Euro-Mediterranean Countries. This area was chosen as buildings typically have little or no insulation due to the regional mild climate; however, particularly with climate change, indoor hygrothermal comfort is poor. The collection of information allows some conclusions to be reached about the different bio- wastes already studied and identify gaps in the literature.
- Liquefaction optimization of peel of potato Solanum tuberosum L. var Monalisa.Publication . Dulyanska, Y.; Cruz-Lopes, Luísa; Esteves, Bruno; Guiné, Raquel P. F.; Ferreira, José; Domingos, IdalinaThe potato (Solanum tuberosum L.) is native to South America, in the Andes Mountains where it was consumed by native populations 1. According to the Food and Agriculture Organization of the United Nations (FAO), there has been a large increase in potato production in Latin America and Asia, especially China, that in 2018 was the largest producer followed by India. These two countries represented almost a third of the potatoes consumed in the world 1. In Portugal, the most widely planted potato is Solanum tuberosum L. var Monalisa, that is used by potatoes’ processing industry, generating tons of potato peel waste annually. The waste from the potato industry accounts for approximately 27% of total production. The objective of this work was to evaluate the potentiality of potato industrial residues to be liquefied by polyhydric alcohols and the chemical transformations observed in this process with subsequent use to produce polyurethane foams. Potato peel waste (PPW) was dried in an oven, crushed in the Retsch SMI mill and sifted in a vibratory sieve model Retsh 5657 HAAN 1 for 30 minutes. The fractions obtained were > 35 mesh, 35-40 mesh (0.500-0.425 mm); 40-60 mesh (0.425-0.250 mm); 60-80 mesh (0.250-0.180 mm) and 80 mesh (< 0.180 mm). The liquefactions were made in an oil-heated double-shirt reactor with a mixture of glycerol and ethylene glycol 1:1, catalyzed by 3% sulfuric acid. The effect of particle size (<80 mesh at >35 mesh) temperatures (140 oC - 180 oC), ratio material/solvent (1:5, 1:7, 1:10, 1:12) and times (15-60 min) were studied. The Fourier Transform Infrared Spectroscopy by Attenuated total reflection (FTIR-ATR) was used to evaluate the functional groups present in the original sample of PPW, in the liquefied sample and in the solid residue obtained. Liquefaction percentage with increased temperature, time, material/solvent ratio and granulometry is presented (Figure 1). Results show that liquefaction performed at 180 oC with a 1:10 material/solvent ratio, increases along time, reaching a maximum at 60 min. Similarly, liquefactions made during 60 min with a 1:10 material/solvent ratio show that there is an increase in liquefaction yield with the increase in temperature until 180 oC. A higher temperature could increase the liquefaction yield but would lead to a higher energy consumption in the process. There seems to be no significative advantage in increasing material/solvent ratio above 1:7, although the liquefaction yield increases for higher ratios. Granulometry testing shows that the smaller the particle the best is the liquefaction percentage. It was concluded that the best liquefaction yield, of approximately 90%, was obtained with a temperature of 180 oC, for 60 min and particle size <80 mesh for PPW. This material has good properties to be converted in a liquid mixture that can be used later, on the production of polyurethane foams (Figure 1). The PPW spectrum exhibits the common bands for agricultural materials (Figure 2). The main differences between the solid material and the liquefied material is the high OH band with a peak at around 3300 cm-1 for both the original material and the liquefied, while the peak for the solid residue is at higher wavenumbers. The liquefied sample has a considerable higher OH peak than the solid samples, which is probably due to the polyalcohols used for the liquefaction. The band at 1740 cm-1 (non-conjugated C=O bonds) is higher in the solid residue spectrum and smaller in the liquefied material. Similarly Jin et al. 2 observed the absence of C=O groups after the liquefaction of enzymatic hydrolysis lignin. The highest peak in the original and in the liquefied material spectra is the peak at 1100 cm-1 which has been attributed to C–O stretching vibrations in carbohydrates. This is in accordance with several chemical compositions reported for PPW 1. In the liquefied material a new peak appears at around 860 cm-1, which can be due to stretching in the pyranose ring as stated before 3.
- Physical and Mechanical Properties of Juvenile Wood of Anadenanthera peregrina (L.) Speg. from ThinningPublication . Silva, Emilly Soares Gomes; Gonçalves, Fabricio Gomes; Segundinho, Pedro Gutemberg Alcântara; Filho, Cleyton Machado Prata; Lopez, Yonny Martinez; Chaves, Izabella Luzia Silva; Gustave, Donatian; Fassarella, Michelângelo Vargas; Esteves, BrunoReducing the rotation period through thinning and changing planting spacing can influence the technological properties of wood, with little attention paid to the effects of these variables on the raw material, which limits its processing in the wood sector. This work aimed to evaluate the physical and mechanical properties of wood from Anadenanthera peregrina juveniles thinned in three planting spacings (3 m × 3 m, 4 m × 4 m, and 5 m × 5 m). The physical properties in the base-top and pith–shell directions and the mechanical properties of the samples were evaluated. The results indicate better technological properties for wood with larger spacings. The physical properties showed decreasing trends in the base-top direction and increasing trends in the pith-bark direction, with a distinct trend in the degree of collapse. The average basic density of the different planting spacings varied between 0.47 g cm−3 and 0.63 g cm−3. The mechanical properties obtained for the 4 m × 4 m spacing were superior to those of the other spacings. Wood from young A. peregrina is an alternative for industrial processing, as wood from higher planting densities is more suitable for purposes that require resistance and rigidity.
- Influence of Chemical Composition on Heating Value of Biomass: A Review and Bibliometric AnalysisPublication . Esteves, Bruno; Sen, Umut; Pereira, HelenaAbstract: Biomass has become an increasingly important resource for energy generation. The influence of the chemical composition on the heating value of biomass has not been a thoroughly studied subject, as shown by a bibliometric analysis. It is well known that the heating value of lignin is significantly higher (23.26–25.58 MJ/kg) than that of polysaccharides (18.6 MJ/kg), while extractives often have HHVs over 30 MJ/kg, depending on their oxidation levels. Therefore, the proportions of the chemical components in biomass determine its HHV. Softwoods generally have higher HHVs than hardwoods due to their higher contents of lignin and lipophilic resin. Ashes are incombustible, and a high ash content leads to a lower HHV in biomass. Several models have been proposed to correlate the heating values and chemical compounds of biomass, but the most accurate models are based on the lignin from extracted samples, while good correlations between lignin and extractives have also been reported. No good correlations have been obtained with polysaccharide compounds.
- Maritime pine land use environmental impact evolution in the context of life cycle assessmentPublication . Ferreira, José; Esteves, Bruno; Cruz-Lopes, Luísa; Domingos, IdalinaBetween 2005 and 2015, the forest area occupied by maritime pine trees in Continental Portugal decreased by about 10.6%, and the existing volume decreased by about 18.4%mainly due to fires and pests (e.g., nematode) that occurred during this period. The purpose of this study was to study the evolution of the land use environmental impact of 1m3 of maritime pine, standing in Portuguese forest, during that period using the model by Milà i Canals based on soil organic matter measured by soil organic carbon. Results show that the land use impact category increased from 16,812 kg C deficit in 2005 to 18,423kg C deficit in 2015. Land transformation to forest roads is the main contribution for land use impact representing 54%of the total value followed by land occupation as forest that represents about 40%.
- Extraction of Phenolic Compounds from Cherry Seeds: A Preliminary StudyPublication . Dulyanska, Yuliya; Cruz-Lopes, Luísa; Esteves, Bruno; Ferreira, José; Domingos, Idalina; Lima, Maria João; Correia, Paula; Ferreira, Manuela; Fragata, Anabela; Barroca, Maria João; Moreira da Silva, Aida; Guiné, Raquel P. F.Agri-food waste has proved to be a valuable bioresource that can be used to obtain a variety of valuable materials, ingredients and chemicals. The optimum conditions for extracting bioactive compounds from sweet cherry seeds (SCS) with different solvents and temperatures were tested in this work. The choice criteria were based on the most efficient extracting capacity while looking for cleaner techniques with lower health or environmental impacts. Some extracting solvents (methanol, ethanol and water) were tested in different combinations and temperatures. The obtained extracts were evaluated for total phenolic compounds and some families of phenolics as well, using spectrophotometric methods. The results obtained showed that the highest extraction of total phenolic compounds was at 70 °C with 60:40 ratio water:ethanol (2.65 mg GAE/g), while maximum flavonoids were obtained at 80 °C and 50% ethanolic aqueous solution (7.26 mg QE/g). The highest value for ortho-diphenols was 21.47 mg GAE/g for 50 °C and water:ethanol 50:50 solution. The highest proanthocyanidins and flavonols were obtained for 50:50 solution at 70 °C (6.43 mg CE/g and 3.88 mg QE/g, respectively), while the same solution at 80 °C allowed obtaining maximum phenolic acids (1.68 mg CAE/g). The extraction of anthocyanins was found to vary significantly with concentration and temperature, being highest in the range 35–40 °C, when using an 80:20 water:ethanol solution. Hierarchical clustering showed three clusters, while factor analysis resulted in two factors and four groups of samples. In conclusion, it was found that extracts obtained from sweet cherry seeds have relevant bioactive compounds with applications in the food, pharmaceutical or cosmetic industries.