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- Termite Resistance, Chemical and Mechanical Characterization of Paulownia tomentosa Wood before and after Heat TreatmentPublication . Esteves, Bruno M.; Ferreira, Helena; Viana, Hélder; Ferreira, José; Domingos, Idalina J.; Cruz-Lopes, Luísa; Jones, Dennis; Nunes, LinaThe introduction of new species in forest management must be undertaken with a degree of care, to help prevent the spread of invasive species. However, new species with higher profitability are needed to increase forest products value and the resilience of rural populations. Paulownia tomentosa has an extremely fast growth. The objective and novelty of this work was to study the potential use of young Paulownia trees grown in Portugal by using heat treatment to improve its properties, thereby allowing higher value applications of the wood. The average chemical composition of untreated and heat-treated wood was determined. The extractive content was determined by successive Soxhlet extraction with dichloromethane (DCM), ethanol and water as solvents. The composition of lipophilic extracts was performed by injection in GC-MS with mass detection. Insoluble and soluble lignin, holocellulose and α-cellulose were also determined. Physical (density and water absorption and dimensional stability) and mechanical properties (bending strength and bending stiffness) and termite resistance was also determined. Results showed that extractive content increased in all solvents, lignin and α-cellulose also increased and hemicelluloses decreased. Compounds derived from the thermal degradation of lignin were found in heat-treated wood extractions. Dimensional stability improved but there was a decrease in mechanical properties. Resistance against termites was better for untreated wood than for heat-treated wood, possibly due to the thermal degradation of some toxic extractives.
- Influence of Seasonal and Yearly Variation on Phenolic Profiles, Caffeine, and Antioxidant Activities of Green Tea (Camellia sinensis (L.) Kuntze) from AzoresPublication . Paiva, Lisete S.; Lima, Elisabete; Motta, Madalena; Marcone, Massimo; Baptista, JoséThis study compares the antioxidant properties (RSA(DPPH)-DPPH radical scavenging activity, FRAP-ferric reducing activity power, and FIC-ferrous ion-chelating activity), the total phenolics (TP), total flavonoids (TF), and catechin profiles, as well as the caffeine content of Azorean Camellia sinensis green tea collected in seasons of two different years. The RSA(DPPH) showed some variation between 2019 and 2020, and presented, in general, better results in 2020 as well as during the summer seasons. The FRAP was also noted to be at its highest in July and August of the two investigated years (6.64 and 6.40 mu g/mL in 2019 and 5.85 and 5.46 mu g/mL in 2020). According to FIC activity, the August 2019 sample exhibited the highest value (76.18%). The TP varied between 291.14 and 326.93 mg gallic acid equivalents (GAE)/g of dried extract (DE) in 2019 and between 300.25 and 320.58 mg GAE/g DE in 2020. Concerning the TF, the values varied between 51.85 and 67.93 mg rutin equivalents (RE)/g DE in 2019 and between 50.27 and 69.57 mg RE/g DE in 2020. Epicatechins derivatives, determined by HPLC, presented higher values in all samples from 2020 compared to 2019, and the same was observed for esterified catechins. The epigallocatechin-3-gallate content was also higher in all samples from 2020 (214.52-240.16 mg/g DE) compared to 2019 (140.91-210.83 mg/g DE). Regarding caffeine content (12.86-20.45 mg/g DE in 2019 and 13.19-29.35 mg/g DE in 2020), the samples from April and June exhibited similar values in both years. In general, green tea samples exhibited better results in 2020 than in 2019, with the exception of FIC activity, while the varied TP and TF contents in certain months reflect the impact of climatic variation on tea quality.
- Diversity Patterns of Dung Beetles along a Mediterranean Elevational GradientPublication . Mantoni, Cristina; Tsafack, Noelline; Palusci, Ettore; Di Pietro, Stefano; Fattorini, SimoneMost studies of biodiversity–elevational patterns do not take species abundance into consideration. Hill numbers are a unified family of indices that use species abundance and allow a complete characterization of species assemblages through diversity profiles. Studies on dung beetle responses to elevation were essentially based on species richness and produced inconsistent results because of the non-distinction between different habitats and the use of gradients dispersed over wide areas. We analyzed dung beetle diversity in a Mediterranean mountain (central Italy) for different habitats (woodlands vs. grasslands) and taxonomic groups (scarabaeids and aphodiids). Scarabaeids were the most abundant. Since scarabaeids are able to construct subterranean nests, this indicates that the warm and dry summer climatic conditions of high elevations favor species capable of protecting their larvae from desiccation. Dung beetles were more abundant and diversified in grasslands than in woodlands, which is consistent with their preference for open habitats. In the woodlands, diversity increased with increasing elevation because of increasing tree thinning, whereas, in the grasslands, diversity decreased with elevation because of increasingly harsher environmental conditions. These results indicate a trade-off in the beetle response to elevation between the positive effects of increasing the availability of more suitable habitats and the decrease of optimal environmental conditions.
- Occurrence of Volcanogenic Inorganic Mercury in Wild Mice Spinal Cord : Potential Health ImplicationsPublication . Navarro-Sempere, Alicia; García, Magdalena; Rodrigues, Armindo; Garcia, Patrícia; Camarinho, Ricardo; Segovia, YolandaMercury accumulation has been proposed as a toxic factor that causes neurodegenerative diseases. However, the hazardous health effects of gaseous elemental mercury exposure on the spinal cord in volcanic areas have not been reported previously in the literature. To evaluate the presence of volcanogenic inorganic mercury in the spinal cord, a study was carried out in São Miguel island (Azores, Portugal) by comparing the spinal cord of mice exposed chronically to an active volcanic environment (Furnas village) with individuals not exposed (Rabo de Peixe village), through the autometallographic silver enhancement histochemical method. Moreover, a morphometric and quantification analysis of the axons was carried out. Results exhibited mercury deposits at the lumbar level of the spinal cord in the specimens captured at the site with volcanic activity (Furnas village). A decrease in axon calibre and axonal atrophy was also observed in these specimens. Given that these are relevant hallmarks in the neurodegenerative pathologies, our results highlight the importance of the surveillance of the health of populations chronically exposed to active volcanic environments.
- Expert knowledge-based co-development of scenarios for maritime spatial planning in the Northeast AtlanticPublication . Calado, Helena; Pegorelli, Camila; Vergílio, Marta H. S.; Hipólito, Cláudia; Campos, Aldino; Moniz, Fabiana; Costa, Ana Cristina; Silva, C. Pereira da; Fonseca, Catarina; Santos, C. Frazão; Gabriel, Daniela; Guerreiro, J.; Gil, Artur José Freire; Johnson, David; Ng, Kiat; Monwar, M. M.; Ventura, Maria A.; Suárez-de Vivero, J. L.; Pinho, Mário Rui; Borges, Paulo Jorge Soares de Amaral; Caña-Varona, Mario; Papaioannou, E. A.Scenarios constitute narratives or storylines that reasonably describe how the future is likely to unfold. The usefulness of scenarios in Maritime Spatial Planning (MSP) is now recognised within policy and research, with many institutions urging the development of likely trajectories in the future state of the marine environment and space. However, little progress exists in the actual development and application of actual scenario building approaches. This paper presents the methodology and results of such an approach developed within the framework of the “Geographical and Political Scenarios in Maritime Spatial Planning for the Azores and North Atlantic (GPS Azores)” project. A scenario-building approach for MSP in the area is developed and future scenarios’ storylines are formulated through the active engagement of regional experts. Outcomes from the analysis enable identifying the major risks and opportunities in the management and use of marine space and key maritime sectors, under different scenarios. Three storylines are developed representing distinct trajectories in the use and governance of marine space: (i) Nature at Work; (ii) Business-as-usual; and (iii) Blue Development. Final storylines are the outcome of intense experts’ engagement throughout the scenario-building exercise, stressing the usefulness of such participative approaches. Results can assist policymakers in the context of an adaptive and participatory MSP approach. The methodology can be tailored to other regions, while results can be revisited and adapted as new information and knowledge emerge.
- Can the growing of transgenic maize threaten protected Lepidoptera in Europe?Publication . Lövei, Gábor L.; Lang, Andreas; Ferrante, Marco; Bacle, VictorWe evaluated whether protected European butterflies can potentially be at risk if transgenic maize is extensively grown in Central Europe. We explored potential consequences of both insect resistant (IR) and herbicide resistant (HR) transgenic maize. IR maize can produce pollen that is toxic to lepidopteran larvae, and this puts butterfly species at possible risk if the presence of young larvae coincides with maize flowering, during which large quantities of maize pollen can be deposited on vegetation. By considering the timing of maize flowering in Europe and the phenology of the protected Lepidoptera species, we found that 31 species had at least one generation where 50% of the larval stage overlapped with maize flowering, and 69 species for which first instar larvae were present during maize pollen shedding. HR maize allows high concentration herbicide treatments on fields without seasonal limitation, which can drastically reduce weed densities. In cases where such weed species are host plants for protected butterflies, reduced host plant/food availability can result, causing population decreases. By using published information, we first identified the important weed species in major maize-growing European countries. Subsequently, we checked whether the host plants of protected Lepidoptera included species that are common maize weeds. We identified 140 protected species having food plants that are common weeds in one or more of the major European maize-growing countries. If HR maize is grown in Europe, there is a potential hazard that their food plants will seriously decline, causing a subsequent decline of these protected species.
- Effects of cover crops on beetle assemblages in tea plantationsPublication . Chen, Li-Lin; Pozsgai, Gabor; Li, Xiang-Yu; Li, Lei; Reddy, Gadi V. P.; You, Min-ShengColeoptera are visible members of food webs in tea plantations, with high species richness and abundance. Many tea pests, as well as natural enemies, are members of this order, so a knowledge of how groundcovers affect beetles can aid pest management. We collected beetles in a replicated field experiment in the Wuyi Mountains, Fujian Province, China. Tea was intercropped with Paspalum notatum or Chamaecrista rotundifolia, or rows were cleared to bare ground, or in the control they were left unmanaged to allow weeds to grow naturally. Sampling, done by sweep netting and vegetation beating, was conducted monthly, between May 2006 and April 2008, and Coleoptera abundance, biomass, species richness and assemblage structures were compared between groundcover treatments. Total beetle abundance and species richness were significantly higher in tea intercropped with C. rotundifolia and bare ground than in naturally grown weedy control. Whilst there was no difference between predator assemblages among treatments for any measure, herbivores were more abundant, weighed more, and were more diverse in C. rotundifolia treatments than in weedy control. Biomass and species richness were also greater in plots with P. notatum groundcover than those in weedy control. We found that beetle assemblages varied both seasonally and with ground cover treatment, but the potential pest control impact of more species-rich beetle assemblages was mixed, and further work is needed to gain information on trophic groups with potential benefits for use in non-insecticidal pest management.
- An annotated checklist of ladybeetle species (Coleoptera, Coccinellidae) of Portugal, including the Azores and Madeira ArchipelagosPublication . Soares, António O.; Calado, Hugo Renato; Franco, José Carlos; Aguiar, António Franquinho; Andrade, Miguel M.; Zina, Vera; Ameixa, Olga M. C. C.; Borges, Isabel; Magro, AlexandraA comprehensive annotated checklist of the ladybeetle species of Portugal, including the Azores and Madeira archipelagos, is presented. The Coccinellidae fauna comprises a total of 101 species: 83 from the Mainland, 39 from Madeira, and 32 from the Azores. The listed species are distributed among 2 sub-families and 13 tribes: within the subfamily Microweiseinae, Madeirodulini (1 species), Serangiini (2 species), and within the subfamily Coccinellinae, Azyini (1 species), Chilocorini (4 species), Coccidulini (7 species), Coccinellini (30 species), Epilachnini (4 species), Hyperaspidini (7 species), Noviini (2 species), Platynaspini (1 species), Scymnini (37 species), Stethorini (3 species), and Sticholotidini (2 species). The Portuguese fauna comprises 10 exotic species: 5 present in the Mainland, 7 in Madeira, and 6 in the Azores. Harmonia axyridis (Pallas, 1773) from Madeira, Propylea quatuordecimpunctata (Linnaeus, 1758) from the Azores, Delphastus catalinae (Horn, 1895) from the Azores and Madeira, Nephus (Geminosipho) reunioni (Fürsch, 1974) and Nephus (Nephus) voeltzkowi Weise, 1910 from Madeira and Microserangium sp. from the Mainland, are reported for the first time. Some species are considered doubtful records, as explained in the text. These results were obtained by compiling information on the available literature regarding ladybeetle species on the Portuguese mainland and insular territories, and original data.
- Das múltiplas modernidades à pós-modernidade : uma reflexão a partir de Shmuel EisenstadtPublication . Fontes, Paulo VitorinoA ideia de modernidades múltiplas subentende que a melhor forma de compreender o mundo contemporâneo e de explicar a história da modernidade é concebê-la como história de constituição e reconstituição sucessiva de uma multiplicidade de programas culturais. O conceito “modernidades múltiplas” tem duas implicações. A primeira é que modernidade e ocidentalização não são idênticas; o padrão ou padrões ocidentais de modernidade não constituem as únicas modernidades “autênticas”, embora tenham sido historicamente precedentes e constituam uma referência central para outras visões da modernidade. A segunda é que o termo modernidades inclui o reconhecimento de que essas modernidades não são “estáticas”, mas que se encontram em contínua transformação. Transformações que conduzem à pós-modernidade que tem ocupado um lugar primordial no debate de ideias contemporâneo, penetrando uma miríade de questões diversas com ramificações políticas da mais variada ordem.