Browsing by Issue Date, starting with "2022-04"
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- O neo-realismo e a história do PCP: três notas de definiçãoPublication . Carmo, Carina Infante do
- Transdisciplinary, co-designed and adaptive management for the sustainable development of rongcheng, a coastal city in China in the context of human activities and climate changePublication . Tu, Chen; Ma, Haiqing; Li, Yuan; Fu, Chuancheng; You, Zai-Jin; Newton, Alice; Luo, YongmingHalf the population of China live in coastal zones where 70% of large cities are also located. Intensive human activities pose significant environmental and ecological hazards to these cities that are already vulnerable to natural hazards and climate change. The sustainable development of coastal cities is thus both a national and international issue. Rongcheng is a typical coastal city in east China. It is a national marine ranch demonstration area that is subjected to multi-stressors from human activities and climate change. The dominant economic sectors include aquaculture and fisheries, agriculture, shipping and tourism. A multitude of resulting pressures come mainly from intensified human activities, such as intensive aquaculture, overfishing, industrial pollutants, agricultural runoff, land reclamation and port expansion. In addition, Rongcheng is also facing exogenic pressures from extreme climate events such as intensified storms, storm surges, droughts and sea ice. A growing awareness of these problems brought together a trans-disciplinary group from local government, research institutions, local practitioners and coastal representatives to jointly explore and co-design adaptive coastal management options. In this transdisciplinary study, a social-ecological analysis based on a combination of the Systems Approach Framework and the Drivers-Pressures-States-Impacts-Responses framework was used to analyze and formulate an adaptive management plan for the sustainability of Rongcheng. More than 40 stakeholders including government, companies, civil society and institutions participated in the study through questionnaires and on-site meetings. A statistical analysis of the results identified urgent issues impeding the sustainable development of Rongcheng. The issues identified were poorly regulated aquaculture, loss of shoreline, and the decline of seagrass and cultural heritage.The study identified management options and measures, some of which were adopted by the local government in a co-designed management plan. The measures included upgrading of aquaculture industry, habitat conservation and restoration, and the development of cultural tourism. Another outcome was the increased knowledge exchange between stakeholders to inform management, policy, and decision making, as well as raised awareness of vulnerability to natural hazards and climate change. The success of this case study provides a reference for the adaptive management of other coastal cities and their sustainable development in a changing climate.
- Free vibrations analysis of composite and hybrid axisymmetric shellsPublication . Simões Moita, José Mateus; Araujo, Aurelio L.; Franco Correia, Victor; Mota Soares, Cristóvão M.The free vibration of laminated composite (C) and hybrid axisymmetric shell structures, consisting of a composite laminated material sandwiched between two functionally graded material laminas (F1/C/F2), is analysed in the present work. The numerical solutions are obtained by expanding the variables in Fourier series in the circumferential direction and using conical frustum finite elements in the meridional direction. The implemented finite element is a simple conical frustum with two nodal circles, with ten degrees of freedom per nodal circle. This model requires only a reduced number of finite elements to model the geometry of axisymmetric structures, the integration procedures use one Gauss point, and the through the thickness properties variation in FGM laminas is modelled by a small number of virtual layers, resulting a very high computational efficiency. The inhouse developed code presents very good solutions when compared with results obtained by alternative available models.
- Coronal brain atlas in stereotaxic coordinates of the African spiny mouse, acomys cahirinusPublication . Vitorino, Marta; S, Simão; Moreira, João B.; Nogueira‐Rodrigues, Joana; Silva, Joana A; Sofia Lourenço, Ana; Vitor Fernandes, Dr; Sousa, Monica M.; Tiscornia, Gustavo; Araújo, Inês MariaThe African spiny mouse (Acomys cahirinus) is an emerging model of mammalian epimorphic regeneration that has aroused the interest of the scientific community in the last decade. To date, studies on brain repair have been hindered by the lack of knowledge on the neuroanatomy of this species. Here, we present a coronal brain atlas in stereotaxic coordinates, which allows for three-dimensional identification and localization of the brain structures of this species. The brain of 12-week-old spiny mice was mapped in stereotaxic coordinates using cresyl violet-stained brain sections obtained from coronal cryosectioning of the brain after transcardial perfusion with fixative. The atlas is presented in 42 plates representing sections spaced 240 mu m apart. Stereotaxic coordinates were validated using both a model of Parkinsonian lesion of the striatum with 6-hydroxydopamine and labeling of the corticospinal tract in the spiny mouse spinal cord using AAV1/2-GFP intracortical injections. This work presents a new tool in A. cahirinus neurobiology and opens new avenues of research for the investigation of the regenerative ability of A. cahirinus in models of brain disorders.
- Impact of high-pressure homogenization on the cell integrity of tetradesmus obliquus and seed germinationPublication . Ferreira, Alice; Figueiredo, Daniel; Ferreira, Francisca; Ribeiro, Belina; Reis, Alberto; da Silva, Teresa Lopes; Gouveia, LuisaMicroalgae have almost unlimited applications due to their versatility and robustness to grow in different environmental conditions, their biodiversity and variety of valuable bioactive compounds. Wastewater can be used as a low-cost and readily available medium for microalgae, while the latter removes the pollutants to produce clean water. Nevertheless, since the most valuable metabolites are mainly located inside the microalga cell, their release implies rupturing the cell wall. In this study, Tetradesmus obliquus grown in 5% piggery effluent was disrupted using high-pressure homogenization (HPH). Effects of HPH pressure (100, 300, and 600 bar) and cycles (1, 2 and 3) were tested on the membrane integrity and evaluated using flow cytometry and microscopy. In addition, wheat seed germination trials were carried out using the biomass at different conditions. Increased HPH pressure or number of cycles led to more cell disruption (75% at 600 bar and 3 cycles). However, the highest increase in wheat germination and growth (40-45%) was observed at the lowest pressure (100 bar), where only 46% of the microalga cells were permeabilised, but not disrupted. Non-treated T. obliquus cultures also revealed an enhancing effect on root and shoot length (up to 40%). The filtrate of the initial culture also promoted shoot development compared to water (21%), reinforcing the full use of all the process fractions. Thus, piggery wastewater can be used to produce microalgae biomass, and mild HPH conditions can promote cell permeabilization to release sufficient amounts of bioactive compounds with the ability to enhance plant germination and growth, converting an economic and environmental concern into environmentally sustainable applications.
- SpectraNet–53: A deep residual learning architecture for predicting soluble solids content with VIS–NIR spectroscopyPublication . A. Martins, J.; Guerra, Rui Manuel Farinha das Neves; Pires, R.; Antunes, M.D.; Panagopoulos, T.; Brázio, A.; Afonso, A.M.; Silva, L.; Lucas, M.R.; Cavaco, A.M.This work presents a new deep learning architecture, SpectraNet-53, for quantitative analysis of fruit spectra, optimized for predicting Soluble Solids Content (SSC, in Brix). The novelty of this approach resides in being an architecture trainable on a very small dataset, while keeping a performance level on-par or above Partial Least Squares (PLS), a time-proven machine learning method in the field of spectroscopy. SpectraNet-53 performance is assessed by determining the SSC of 616 Citrus sinensi L. Osbeck 'Newhall' oranges, from two Algarve (Portugal) orchards, spanning two consecutive years, and under different edaphoclimatic conditions. This dataset consists of short-wave near-infrared spectroscopic (SW-NIRS) data, and was acquired with a portable spectrometer, in the visible to near infrared region, on-tree and without temperature equalization. SpectraNet-53 results are compared to a similar state-of-the-art architecture, DeepSpectra, as well as PLS, and thoroughly assessed on 15 internal validation sets (where the training and test data were sampled from the same orchard or year) and on 28 external validation sets (training/test data sampled from different orchards/years). SpectraNet-53 was able to achieve better performance than DeepSpectra and PLS in several metrics, and is especially robust to training overfit. For external validation results, on average, SpectraNet-53 was 3.1% better than PLS on RMSEP (1.16 vs. 1.20 Brix), 11.6% better in SDR (1.22 vs. 1.10), and 28.0% better in R2 (0.40 vs. 0.31).
- A new approach to palynostratigraphy of the middle–late Famennian Gafo Formation, southern sector of the Pulo do Lobo Domain, SW Iberia (Portugal and Spain)Publication . Mendes, Márcia; Pereira, Zélia; Vaz, Nuno; Díez-Montes, Alejandro; Matos, João X.; Albardeiro, Luis; Manuel Carvalho Fernandes, Paulo; Jorge, Raul; Chew, DavidNew palynological results from the Gafo Formation (southern sector of the Pulo do Lobo Domain, South Portuguese Zone) are integrated with recently studied sections and drillholes from the Portuguese and Spanish sectors. A total of 44 samples were studied, 27 of which were positive for palynomorph taxonomy. This research revealed well preserved palynological assemblages, including 73 spore species allocated to 28 genera, four acritarch genera, three prasinophyte algae genera plus common chitinozoan remains. Some additional forms were retained under open nomenclature. From this, the first complete age determination for the Gafo Formation in Portugal and Spain was achieved, indicating a middle Famennian (Grandispora gracilis–Grandispora famenensis, GF Biozone) to a late Famennian (Grandispora echinata, VH Biozone) age. A greywacke sample from the same Gafo Formation was dated by U–Pb zircon geochronology and a maximum depositional age of 369 ± 2.5 Ma was obtained. A correlation between these palynological and U–Pb zircon data and the palynoflora assemblages of previous authors was made, as well as with the ages of felsic volcanic rocks found intercalated in the Gafo Formation, confirming the complex stratigraphy of Pulo do Lobo Domain. The results are consistent with stratigraphic mapping and structural interpretations, allowing a middle–late Famennian age (GF and VH Biozone) to be assigned to the Gafo Formation sedimentary rocks. This work has also contributed to a reinterpretation of Gafo Formation depositional facies correlatives (e.g. the Santa Barbara Group in Spain) as being the same lithological unit.
- Service guarantees in an e-commerce platform: proposition of a framework based on customers' expectations, negative experiences and behavioural responsesPublication . Oliveira, Alessandro Silva de; Souki, Gustavo; Silva, Dirceu da; Rezende, Daniel Carvalho de; Batinga, Georgiana LunaPurpose Companies' relationship with their customers through e-commerce platforms has increased considerably in the past few years, bringing new challenges concerning service guarantees (SG). This study aims to propose a framework of the relations between customers' expectations on SG, their negative experiences and their attitudes and behavioural intentions towards an e-commerce platform. Design/methodology/approach The research had a qualitative and descriptive approach. Testimonials from clients of an online e-commerce platform were obtained through interviews via videoconference and non-participant observation on a complaints website in Brazil. The testimonies were analysed through content analysis. Findings The customer expectations regarding the SG offered by the e-commerce platform are congruent with the five categories of the theory that support this research. Customer testimonials on the complaints site show that their negative experiences with the e-commerce platform generated negative emotional, cognitive and behavioural responses towards the company. A framework was proposed, including customers' expectations regarding SG, their negative experiences and their repercussions on clients' attitudes and behavioural intentions. Originality/value This article is the only that contemplates customers' expectations about SG in an e-commerce platform, relating them to attitudes and behavioural intentions. Thus, its framework demonstrates the relationships between customer expectations about SGs, their negative experiences and attitudinal and behavioural repercussions. This article brings academic and managerial contributions for companies and managers of e-commerce platforms. It contributes to clients and consumer protection associations by revealing problems they face with SG on e-commerce platforms. This research can be used by those responsible for elaborating laws and public policies to regulate and inspect the relationships between e-commerce platforms and their customers.
- Mitochondrial ATP synthesis activated by exciton energy transfer from Müller cell intermediate filamentsPublication . Khmelinskii, Igor; Makarov, Vladimir I.ATP production by mitochondria isolated from yeast cells (S. cerevisiae) was accelerated by exciton energy transfer from intermediate filaments (IFs). The effect was dependent on mitochondrial concentration and the intensity of light used to generate excitons. Presumably, mitochondrial cytochrome C (CC) was activated by IF exciton energy transfer to CC in the inner mitochondrial membrane (IMM), generating electronically excited CC, and the respective excitation energy was then used in the ATP production chain. A qualitative model was proposed describing observations, although more experiments are required before the detailed mechanisms could be deduced. The present results support the earlier proposed hypothesis of ATP production in vertebrate retina by excess photons in daytime, when retina needs extra energy for recovering the used opsins. Additionally, it shows that at early stages of evolution mitochondria could have been using solar radiation to produce ATP.
- Lexical and semantic training to acquire words in a foreign language: an electrophysiological studyPublication . García-Gámez, Ana Belén; Macizo, PedroAn event-related potential (ERP) study was conducted to evaluate the efficacy of two learning methods for the acquisition of vocabulary in a foreign language (FL). In the semantic method, FL words were presented with pictures denoting their meaning and the learners practiced with a semantic categorization task (to indicate whether FL words were exemplars of a semantic category). In the lexical method, FL words were paired with their translation in the first language (L1) and the learners practiced with a letter-monitoring task (to indicate whether L1-FL words contained a grapheme). A translation task and a picture-naming task were used to evaluate FL acquisition. ERP modulations associated with semantic processing were more evident and broadly distributed in the semantic versus lexical learning group. The pattern of results suggests that a single session of semantic learning favors the establishment of connections between semantics and the words learned in a new language.