Universidade de Évora
  • Évora, Portugal
Recent publications
Photodegradation is the alteration of the materials due to exposure to sunlight. This phenomenon is evident in paint, ink, pharmaceuticals and polymers. In polymers, photodegradation is caused by ultraviolet radiation (300–400 nm), which activates the breaking of C-C bonds and the formation of hydroperoxides, thermolabile substances. Although to a lesser extent, photodegradation also affects more resistant materials such as building stones. In these, it causes a change of color and luminosity due to the oxidation of organic matter or to the change in the valence of ions as Fe²⁺, Mn²⁺. In outdoor weathering, photodegradation is associated with other environmental factors such as rain, moisture, temperature, and condensation, which, in conjunction with sunlight, significantly increase the decay of the natural stone. The following research illustrates an accelerated degradation test on building stone by the UVA light, moisture, spray accelerated weathering tester by reproducing the ASTMG154 Cycle 7. To simulate outdoor weathering, materials are exposed to alternating cycles of UV light and moisture at controlled temperatures. It simulates the effects of natural sunlight and artificial irradiance using special fluorescent UV lamps in the UVA, UVB, and UVC section of the electromagnetic spectrum. A series of physical/aesthetic parameters (e.g., CIE L*a*b* color, gloss, roughness, water vapor permeability) of a selected group of building stones from Portugal is evaluated. Weathering shows an increase of roughness and a sensitive decrease of gloss.
Particle-size analysis on ancient mortars and concretes aggregate is today a common practice in Cultural Heritage and civil engineering. Normally, a particle-size distribution of mortar aggregates on in situ materials is carried out using sieves, following the dissolution of the carbonate binder. This technique needs about 200 g of material per sample and produces a large volume of liquid wastes. Sampling is generally supervised by local authorities especially in the field of cultural heritage. Over the years it has therefore become necessary to devise analytical solutions for collecting the smallest volume of material to preserve the buildings. In this research a non-destructive testing to define the aggregate distribution and their percentage in the mortars and/or concretes is presented. It consists of 2D particle size image analysis performed in thin sections. To evaluate the reliability and limitations of this method, already operated in other research, 20 particle-size distributions, characterized by aggregates with Roundness 0.5 < R < 0.95 and Circularity 0.4 < C < 0.75 were created and analyzed using real sieves. Afterwards, the same particle-distributions were mixed with resin to reproduce a “fake” concrete/mortar. A thin section of this latter was analyzed by appropriate software. The method shows a good prediction of the Resin/Aggregate ratio with uniformity coefficient of 0.88 together with variable reliability of the particle-size distribution.
This paper examines the short-term market reaction of the airline industry to the declaration of COVID-19 as a global pandemic and to the announcements of the effectiveness of COVID-19 vaccines in the US. Using an event study, we observe a negative and statistically significant stock price reaction to the announcement of COVID-19 as a global pandemic. In contrast, we find a positive impact on the stock market due to the announcements of the effectiveness of COVID-19 vaccines in the US. These results are consistent with the investor sentiment hypothesis and the asset-pricing perspective. The empirical results also show a higher stock market reaction to the announcement of the effectiveness of the Pfizer–BioNTech COVID-19 vaccine in the US compared to the announcements of the effectiveness of subsequent vaccines. This result is explained by the innovation race competition effect and the greater reduction in investor uncertainty levels. These reactions were reinforced or mitigated by firm-specific characteristics such as liquidity, size, leverage, ownership concentration, state control and business model (i.e., low-cost versus full-service).
Species differ in their biological susceptibility to extinction, but the set of traits determining susceptibility varies across taxa. It is yet unclear which patterns are common to all taxa, and which are taxon-specific, with consequences to conservation practice. In this study we analysed the generality of trait-based prediction of extinction risk across terrestrial (including freshwater) vertebrates, invertebrates and plants at a global scale. For each group, we selected five representative taxa and within each group we explored whether risk can be related to any of 10 potential predictors. We then synthesized outcomes across taxa using a meta-analytic approach. High habitat specificity was a consistent predictor across vertebrates, invertebrates and plants, being a universal predictor of risk. Slow life-history traits-large relative offspring size, low fecundity, long generation length-, and narrow altitudinal range were also found to be good predictors across most taxa, but their universality needs to be supported with additional data. Poor dispersal ability was a common predictor of extinction risk among invertebrate and plant taxa, but not consistently among vertebrates. The remaining traits (body size, micro-habitat verticality, trophic level, and diet breadth) were useful to predict extinction risk but only at lower tax-onomical levels. Our study shows that despite the idiosyncrasies among taxa, universal susceptibility to extinction exists and several traits might influence extinction risk for most taxa. Informing conservation prior-itization at lower taxonomic scales should however include taxon-specific trait-based predictors of extinction risk.
High turnover in the pharmaceutical industry, the location of placebos in urban spaces, and the high rate of corruption of products in this industry are the distinguishing features of the drug supply chain. us, to survive and maintain competitive advantages in the current business environment, managers are active in this background to implement the theoretical foundations of supply chain management. One of the in uential areas in this category is integrated inventory management, inventory control, and vehicle routing. erefore, this study mainly aims to analyze and de ne a routing problem, inventory in the drug supply chain with perishable products, and travel time dependence on multiple graphs with travel time dependence. e Box-Jenkins forecasting method has been utilized to meet the study's aim and deal with demand uncertainty. is method can identify the best pattern governing the data. Finally, the mathematical model is validated, and managerial perspectives are provided. e study results demonstrated the possibility of achieving cost-saving and reducing product spoilage. Applying the solutions of this model can provide some inherent social and environmental advantages, including reducing tra c load and emissions.
Cytostatic drugs are one of the most important therapeutic options for cancer, a disease that is expected to affect 29 million individuals by 2040. After being excreted, cytostatics reach wastewater treatment plants (WWTPs), which are unable to efficiently remove them, and consequently, they will be released into the aquatic environment. Due to the highly toxic properties of cytostatics, it is particularly relevant to evaluate their potential ecological risk. Yet, cytostatics toxicity data is still not available for various species. In this work, the ecotoxicity of two widely consumed cytostatics, cyclophosphamide (CYP—as a model cytostatic) and mycophenolic acid (MPA—as a priority cytostatic), was evaluated on three freshwater species—Raphidocelis subcapitata, Brachionus calyciflorus, and Danio rerio, and the risk quotient (RQ) was assessed. Both drugs significantly affected the yield and growth inhibition of the microalgae, while for rotifers, the least sensitive species, only significant effects were registered for CYP. These drugs also caused significant effects on the mortality and morphological abnormalities on zebrafish. The estimation of the RQ discloses that CYP seems to pose a low risk to aquatic biota while MPA poses a very high risk. Altogether, these results emphasize the need for more complete environmental risk assessments, to properly prioritize and rank cytostatics according to their potentially toxic effects on the environment and aquatic biota. Graphical abstract
Background Tuberculosis (TB) diagnosis and treatment delays increase the period of infectiousness, making TB control difficult and increasing the fatality rates. This study aimed to determine the evolution of health care service delay (time between the patient’s first contact with the health service and the diagnosis/start of treatment) and patient delay (time between onset symptoms date and the date of first contact with health services) for Pulmonary Tuberculosis (PTB) in Portugal between 2008 and 2017 across different regions, age groups and gender. Methods An exploratory analysis was performed, trends of both delays were studied, and 36 months forecasts were generated. We used the permutation test to test differences between groups and the Seasonal and Trend decomposition using Loess (STL) method and Autoregressive Integrated Moving Average (ARIMA) models for forecasting for both Health and Patient delays. We used data from notified PTB cases in mainland Portugal between 2008 and 2017, provided by the national surveillance system. Results Health delays remained relatively constant while patient delays increased. Females had significantly higher health delays in some regions. Individuals older than 64 had higher health delays than younger individuals, while patient delay for working-age individuals between 15 and 64 years old, presents higher patient delay. Conclusions Forecasts presage that the upward trend of the delays is unlikely to fall in the coming years. It is important to understand the evolution of the delays and predict how these will evolve. Our understanding of the delays behaviours will contribute to better health policies and resources allocation.
The devastating impact that seismic events can cause to societies demands that the underlying physical processes that cause them are better understood. Seismic networks have been increasingly deployed over the years allowing to measure ground motion with great accuracy and, in a few cases, reaching high-density deployments for high-resolution measurements. In this chapter it is described the work conducted to build a high-density seismic network comprised of low-cost network-enabled accelerometer sensors to monitor the Alentejo region. The design resulted in a modular platform that can operate with different sensors. Following a noise performance evaluation, the Analog ADXL355 accelerometer was selected for the deployment phase. Herein, sensor system measurements were compared with a professional seismometer, using two actual seismic events recorded in Portugal. These events allowed to demonstrate the sensors capabilities in detecting weak (2.5 ML) to moderate (3.4 ML) seismic events at short (8 km) and medium (140 km) distances respectively. Comparing obtained measurements with a professional seismometer, however, the sensor prototypes exhibited, as expected, a higher presence of sensor noise. Overall it is concluded that the sensor system has a potential application in seismology.
Networks describe nodes connected by links, with numbers of links per node, the degree, forming a range of distributions including random and scale‐free. How network topologies emerge in natural systems still puzzles scientists. Based on previous theoretical simulations, we predict that scale‐free food webs are favourably selected by random disturbances while random food webs are selected by targeted disturbances. We assume that lower human pressures are more likely associated with random disturbances, whereas higher pressures are associated with targeted ones. We examine these predictions using 351 empirical food webs, generally confirming our predictions. Should the topology of food webs respond to changes in the magnitude of disturbances in a predictable fashion, consistently across ecosystems and scales of organisation, it would provide a baseline expectation to understand and predict the consequences of human pressures on ecosystem dynamics.
Fluvial flooding continues to be a process that has a major impact on society, the environment and the economy. Although its natural triggering factors, the spatial configuration of exposure and vulnerability is expected to play a relevant role in explaining the damage records. The starting point of this research is the use of existing flood susceptibility, exposure and social vulnerability mapping, produced at the parish level, as input data in a Classification and Regression Trees’ (CART) model. Two models were ran, autonomously, that use two databases of flood damage as dependent variables: one including the human damages (fatalities, missing, injured, displaced and evacuated people) from flood events—the DISASTER database; another one that sums the DISASTER cases and the lower impact damages (damages to roads, railroads and buildings). The results show a quite distinct classification of parishes, whether one database is used or the other. The DISASTER database reveals susceptibility as the most relevant flood risk driver in explaining the damage patterns, while the database with all the flood cases identifies exposure as the more relevant driver. In the end, the degree of damages as documented in databases is conditioned by the geographical distribution and overlay configuration of the three flood risk drivers. Finally, the CART classification groups are analyzed at the light of the European Union’s Floods Directive areas of significant potential flood risk. This analysis showed that the Directive’s parishes are interpreted differently—in terms of their positioning in face of the risk drivers—which is explained by the use of distinct impacting-criteria in the construction of the flood damage databases.
Resumen En la enseñanza y en el aprendizaje del portugués y del español, persisten múltiples errores o “fosilizaciones” (Selinker, 1971), que denotan una “transferencia negativa” de la Lengua Materna (Martínez Agudo, 2004) [O L1]. Existen dificultades añadidas debido, entre otros, al “mito de la facilidad” (Almeida Filho, citado en Alonso Rey, 2005), lo que requiere adaptaciones didácticas que minimicen esa interferencia. Con la llegada de los enfoques comunicativos, la enseñanza y el aprendizaje de la gramática fueron despreciados y, con ello, rechazados los drills como herramientas didácticas (Mira & Mira, 2002). Sin embargo, investigaciones recientes (López García, 2016; Sánchez Carrón, 2015) sugieren una revisión crítica de esos enfoques, recomendando una colaboración entre modelos. En esta línea investigativa nos ubicamos, dando a conocer la importancia del uso programado de drills para mejorar la subcompetencia lingüística de los alumnos de una Lengua Extranjera [OL2], paliando las interferencias de su L1. Los resultados de nuestra investigación empírica permiten recomendar el uso planificado de drills, abogando por su recuperación en el campo de la didáctica de las lenguas, en el seno de un enfoque comunicativo de enseñanza y aprendizaje de una LE. Abstract In the teaching-learning of Portuguese and Spanish, multiple errors persist or "fossilizations" (Selinker, 1971), suggesting "negative transfer" of the L1 (Martínez Agudo, 2004) [O L1]. We acknowledge its increasing difficulties, arising from, among other factors, the "myth of ease" (Almeida Filho, cited in Alonso Rey, 2005), thus requiring didactic adaptations that may minimize such interference. With the advent of the communicative approach, the teaching-learning of grammar was neglected and, with it, drills were discarded as didactic tools (Mira & Mira, 2002). However, recent research (López García, 2016; Sánchez Carrón, 2015) suggests a critical revision of communicative approaches, recommending a collaboration between models. This article is inscribed in this research line, revealing the importance of the programmed use of drills to improve the linguistic subcompetence of students of a Foreign Language (Target Language [OL2],), mitigating the interferences of their L1. The results of our empirical investigation allow us to recommend the programmed use of drills and advocates their recovery in the field of Language Teaching, within a communicative approach to a Foreign Language teaching-learning process.
The Ice, Cloud and land Elevation Satellite-2 (ICESat-2) provides an extraordinary opportunity to support global large-scale forest carbon mapping, but further research is needed in order to obtain wall-to-wall forest aboveground biomass (AGB) maps with this technology. The effects of vegetation structure on the performance of canopy height and AGB modelling using ICESat-2 photon-counting light detection and ranging (LiDAR) data in Mediterranean forest areas has not been previously studied in the literature. In this study, we combined recent ICESat-2 vegetation (ATL08) data, Airborne Laser Scanning (ALS)- and field-based estimates and a multi-sensor earth observation composite for extrapolation of AGB estimates and AGB mapping. A diverse gradient of forest Mediterranean ecosystems, distributed over 19,744.15 km2 of forest area in the region of Extremadura (Spain), with different species and structural complexity forming 5 different forest types (3 Quercus spp. dominated and 2 Pinus spp. dominated forests), was used to i) evaluate the precision of ICESat-2 canopy height estimations, ii) develop ICESat-2-based AGB models, and iii) generate a spatially continuous prediction of AGB by using data from the satellite missions Sentinel-1 (S1), Sentinel-2 (S2), Phased Array L-band Synthetic Aperture Radar (ALOS2/PALSAR2) and Shuttle Radar Topography Mission (SRTM). First, ALS- and ICESat-2-derived metrics that best described canopy height (p98 and rh98, respectively) were compared at the ATL08 segment level. Second, ALS-based AGB values were derived at the ATL08 segment scale. Third, ALS-based AGB estimates at the ICESat-2 segment level were used as dependent variable to fit ICESat-2-based AGB models. Fourth, a multi-sensor approach was then implemented to predict ICESat-2-derived AGB, by means of a Random Forest (RF) modelling technique, with predictors retrieved from S1, S2, ALOS2/PALSAR2 and SRTM. Finally, RF was used to generate wall-to-wall AGB maps that were compared with field-, ALS- and ICESat-2-based observations. The agreement between ALS- and ICESat-2-derived metrics related to the canopy height distribution was higher for Pinus spp. forest than for the Quercus spp-dominated forests. The ICESat-2-based AGB models yielded model efficiency (Mef) values between 0.56 and 0.80, with a RMSE ranging from 7.76 to 17.71 Mg ha -1 and rRMSE from 19.04 to 55.21%. The multi-sensor RF models provided the following results when compared with the ICESat-2- and ALS-based AGB observations: R2 values of 0.63 and 0.64, and RMSE values of 11.10 Mg ha -1(rRMSE = 28.15%) and 12.28 Mg ha -1(rRMSE = 31.45%), respectively, and an approximately unbiased results (0.03 Mg ha-1 and 0.09 Mg ha -1). When applied to the field-based validation data set (4th Spanish National Forest Inventory (SNFI-4) plots=508), the RF-derived AGB model showed a relatively lower predictive capacity (R2 = 0.45), a higher RMSE value (25.88 Mg ha 1) and slightly biased results (-1.47 Mg ha-1), especially for larger field-derived AGB intervals. The results of this study serve to provide an initial quantitative assessment of the ICESat-2 ATL08 data for large-scale AGB estimation. Findings suggest that a multi-sensor approach may be feasible for extrapolating ICESat-2-derived AGB estimates over areas where field or ALS reference data are not available.
Bi-additive models, are given by the sum of a fixed effects term Xβ and w independent random terms X1Z1,…, XwZw, the components of Z1,…,Zw being independent and identically distributed (i.i.d.) with null mean values and variances σ12,…,σw2. Thus besides having an additive structure they have covariance matrix ∑i=1wσi2Mi, with Mi=XiXit,i=1,…,w, thus their name. When matrices M1,…,Mw, commute the covariance matrix will be a linear combination ∑j=1mγjQj of known, pairwise orthogonal, orthogonal projection matrices and we obtain BQUE for the γ1,…,γm through an extension of the HSU theorem and, when these matrices also commute with M=XXt, we also derive BLUE for γ. The case in which the Z1,…,Zw are normal is singled out and we then also obtain BQUE for the σ12,…,σw2. The interest of these models is that the types of the distributions of the components of vectors Z1,…,Zw may belong to a wide family. This enlarges the applications of mixed models which has been centered on the normal type.
Ecological restoration has the potential to accelerate the recovery of biodiversity and ecosystem services in degraded ecosystems. However, current research queries whether active restoration is necessary. We evaluated plant-pollinator networks during spring at replicated sites within an actively restored quarry, at abandoned quarries undergoing spontaneous restoration, and within a natural reference area, to compare pollinator community composition and function. Overall, we aimed to assess which approach is more effective in rehabilitating pollination networks. We found that while both approaches allowed for the restoration of pollination function, active restoration provided faster recovery: pollination network structure was more similar to the reference ecosystem after 20-30 years of active restoration, than 40 years of natural succession in spontaneously restored areas. Different restoration approaches sustained distinct pollinator communities providing a similar service in different areas: honey bees played an important role in the natural area, bumblebees in the abandoned quarries and wild bees in the restored sites, suggesting a possible conflict between diverse wild bee communities and honey bee homogenized pollinator communities. In quarries, flower resource availability and diversity influenced networks' structural properties by constraining species interactions and composition. In spontaneously restored areas a rich herbaceous layer of ruderal species from early successional stages buffered against the shortage of flower resources at critical periods. Active restoration, though effective, should include practices that consider wild bee communities and mitigate flower resource scarcity. The use of "bridging" plants that flower in different periods, should be considered in active restoration programs to enhance the pollinator community.
Background: We aimed to visualize and classify the time series of COVID-19, tuberculosis (TB) notification, and TB outcomes (cure, treatment abandonment, and death), verify the impact of the new coronavirus pandemic on these indices in Brazil, and verify the presence of spatial autocorrelation between COVID-19 and TB. Methods: This was an ecological time series study that considered TB and COVID-19 cases. Seasonal Trend Decomposition using Loess (STL) was used to trace the temporal trend, Prais-Winsten was used to classify the temporal trend, Interrupted Time Series (ITS) was used to verify the impact of COVID-19 on TB rates, and the Bivariate Moran Index (Global and Local) was used to verify the spatial autocorrelation of events. Results: Brazil and its macro-regions showed an increasing temporal trend for the notification of TB in the pre-pandemic period. Only the Northeast Region showed a decreasing temporal trend for cured cases. For treatment abandonment, all regions except for the Northeast showed an increasing temporal trend, and regarding death, Brazil and the Northeast Region showed an increasing temporal trend. With the ITS, COVID-19 caused a decline in TB notification rates and TB outcome rates. With the global spatial analysis, it was possible to identify the existence of spatial autocorrelation between the notification rate of COVID-19 and the TB notification rate and deaths. With the local analysis, it was possible to map the Brazilian municipalities and classify them according to the relationship between the rates of both diseases and space. Conclusions: COVID-19 influenced the follow-up of and adherence to TB treatment and intensified social vulnerability and, consequently, affected the notification of TB since the relationship between the disease and social determinants of health is already known. The restoration and strengthening of essential services for the prevention and detection of cases and treatment of TB in endemic environments such as Brazil have been oriented as a priority in the global health agenda.
Considering that teaching concerns more than just pedagogical and content knowledge, and that is an emotional practice, teachers must develop emotional competencies. Mayer and Salovey’s model understands emotional intelligence (EI) as a competence that can be learned and developed, and that consists of the adaptive use of emotional information (Mayer et al., 2016). Thus, this Research Topic focuses on the relevance of teachers’ academic training that should include EI as an essential competence for all teachers. The aim was to provide empirical evidence that examines the importance of teachers’ EI, as a crucial emotional competence, highlighting recent studies that can contribute to a new model of teacher education (in academic and in-service education).
The painting The Descent from the Cross, painted in 1620 by Pedro Nunes (1586–1637), presents two large figures with orange-coloured fabrics with conservation problems. Through the analysis of two samples with several analytical techniques, especially scanning electron microscopy combined with X-ray spectroscopy and Raman microscopy, it was possible to conclude that the orange colour is due to a complex artificial pigment made of amorphous arsenic sulphide. It essentially consists of spherical particles obtained by sublimation and condensation, possibly from orpiment, which ended up being joined with irregularly shaped particles resulting from crushing of the residual fraction obtained by solidification and fusion. This is a rare documented case of the extensive use of artificial arsenic sulphides in European easel painting, especially outside Italy. The conservation problems can be explained by the great sensitivity of the arsenic sulphides to photodegradation and the formation of powdery compounds.
Soil acidity can reduce crop growth by increasing bioavailable soil Al, Fe, and/or Mn to toxic levels. The presence of an intact extraradical mycelium (ERM) of arbuscular mycorrhizal fungi (AMF), developed by the native Ornithopus compressus in the acidic soil, can increase wheat growth and prevent symptoms of Mn toxicity. To understand the protective effect of the intact ERM of this native plant on wheat element balance and distribution, in the present study, shoot Al, Fe, K, Zn, Na, and Si levels and their subcellular partitioning were determined by inductively coupled plasma mass spectrometry (ICP-MS), for the first time, for this system. In undisturbed soil, where an intact ERM structure is maintained, wheat shoot growth was promoted, probably due to faster root mycorrhizal colonization. The levels of potentially toxic Al and Fe were reduced, the proportions of the macronutrient K and micronutrient Zn were higher in the symplast, and the Na proportion increased in the vacuole, while Si increased in the apoplast. Overall, the undisturbed soil from O. compressus treatment appeared to influence the uptake and distribution of essential and beneficial elements, as a strategy to reduce the negative effect of soil acidity on wheat growth. Understanding the dynamics of element distribution influenced by stress-adapted AMF on wheat growth can provide more sustainable approaches to intensive agriculture.
Background: The interaction of quality of life (QoL) with functionality, nutrition and depression has been studied, but few studies have compared different realities. Our objective was to compare the associations of QoL with impaired functionality, nutritional status and depressive symptoms among older people patients treated in primary health care (PHC) in Brazil and Portugal. Methods: Cross-sectional, comparative study was conducted with primary data from PHC services in Brazil and Portugal with users over 65 years old. Participants' scores were classified as "impaired" and "preserved" for QoL, functional decline, nutrition and depression. We used Pearson's chi-square test, Fisher's exact test and the Mann-Whitney U test. Results: Our sample had a total of 150 PHC users. We found lower QoL scores in Brazil, which were associated with the risk of functional decline for the domains Physical Functioning, General Health Perceptions, Mental Health dimensions and Physical Health. Nutritional impairment in the group from Portugal included the domains of Vitality and Social Role Functioning. For depressive impairment, Portugal showed an association with the domains Mental Health, Vitality and Social Role Functioning. Conclusions: QoL was associated with functional and nutritional impairment and depressive symptoms, highlighting physical, mental and social characteristics related to the perception of well-being.
In this paper we analyze the relationship between the marketing mix and new product diffusion models. The goal is to obtain a general new product diffusion model that incorporates the classic 4Ps model of the Marketing Mix: Product, Price, Place, Promotion. An empirical study was conducted using mobile broadband adoption data in Japan.
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3,060 members
Ana Rodrigues Costa
  • Department of Chemistry
Rita Payan Carreira
  • Dept of Veterinary Medicine
Gertrudes Saúde Guerreiro
  • Department of Economics
Clara Gracio
  • Department of Mathematics
Tânia Nobre
  • Institute of Mediterranean Agricultural and Environmental Sciences (ICAAM)
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