Browsing by Author "Oliveira, Ana"
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- An urban climate-based empirical model to predict present and future patterns of the Urban Thermal SignalPublication . Oliveira, Ana; Lopes, António; Correia, Ezequiel; Niza, Samuel; Soares, AmílcarAir temperature is a key aspect of urban environmental health, especially considering population and climate change prospects. While the urban heat island (UHI) effect may aggravate thermal exposure, city-level UHI regression studies are generally restricted to temporal-aggregated intensities (e.g., seasonal), as a function of time-fixed factors (e.g., urban density). Hence, such approaches do not disclose daily urban-rural air temperature changes, such as during heatwaves (HW). Here, summer data from Lisbon's air temperature urban network (June to September 2005-2014), is used to develop a linear mixed-effects model (LMM) to predict the daily median and maximum Urban Thermal Signal (UTS) intensities, as a response to the interactions between the time-varying background weather variables (i.e., the regional/non-urban air temperature, 2-hours air temperature change, and wind speed), and time-fixed urban and geographic factors (local climate zones and directional topographic exposure). Results show that, in Lisbon, greatest temperatures and UTS intensities are found in 'Compact' areas of the city are proportional to the background air temperature change. In leeward locations, the UTS can be enhanced by the topographic shelter effect, depending on wind speed - i.e., as wind speed augments, the UTS intensity increases in leeward sites, even where sparsely built. The UTS response to a future urban densification scenario, considering climate change HW conditions (RCP8.5, 2081-2100 period), was also assessed, its results showing an UTS increase of circa 1.0 °C, in critical areas of the city, despite their upwind location. This LMM empirical approach provides a straightforward tool for local authorities to: (i) identify the short-term critical areas of the city, to prioritise public health measures, especially during HW events; and (ii) test the urban thermal performance, in response to climate change and urban planning scenarios. While the model coefficient estimates are case-specific, the approach can be efficiently replicated in other locations with similar biogeographic conditions.
- An urban energy balance-guided machine learning approach for synthetic nocturnal surface Urban Heat Island prediction: a heatwave event in NaplesPublication . Oliveira, Ana; Lopes, António; Niza, Samuel; Soares, AmílcarSouthern European functional urban areas (FUAs) are increasingly subject to heatwave (HW) events, calling for anticipated climate adaptation measures. In the urban context, such adaptation strategies require a thorough understanding of the built-up response to the incoming solar radiation, i.e., the urban energy balance cycle and its implications for the Urban Heat Island (UHI) effect. Despite readily available, diurnal Land Surface Temperature (LST) data does not provide a meaningful picture of the UHI, in these midlatitudes FUAs. On the contrary, the mid-morning satellite overpass is characterized by the absence of a significant surface UHI (SUHI) signal, corresponding to the period of the day when the urban-rural air temperature difference is typically negative. Conversely, nocturnal high-resolution LST data is rarely available. In this study, an energy balance-based machine learning approach is explored, considering the Local Climate Zones (LCZ), to describe the daily cycle of the heat flux components and predict the nocturnal SUHI, during an HW event. While the urban and rural spatial outlines are not visible in the diurnal thermal image, they become apparent in the latent and storage heat flux maps – built-up infrastructures uptake heat during the day which is released back into the atmosphere, during the night, whereas vegetation land surfaces loose diurnal heat through evapotranspiration. For the LST prediction model, a random forest (RF) approach is implemented. RF results show that the model accurately predicts the LST, ensuring mean square errors inferior to 0.1 K. Both the latent and storage heat flux components, together with LCZ classification, are the most important explanatory variables for the nocturnal LST prediction, supporting the adoption of the energy balance approach. In future research, other locations and time-series data shall be trained and tested, providing an efficient local urban climate monitoring tool, where in-situ air temperature observations are not available.
- An urban energy balance-guided machine learning approach for synthetic nocturnal surface Urban Heat Island prediction: a heatwave event in NaplesPublication . Oliveira, Ana; Lopes, António; Niza, Samuel; Soares, AmílcarSouthern European functional urban areas (FUAs) are increasingly subject to heatwave (HW) events, calling for anticipated climate adaptation measures. In the urban context, such adaptation strategies require a thorough understanding of the built-up response to the incoming solar radiation, i.e., the urban energy balance cycle and its implications for the Urban Heat Island (UHI) effect. Despite readily available, diurnal Land Surface Temperature (LST) data does not provide a meaningful picture of the UHI, in these midlatitudes FUAs. On the contrary, the mid-morning satellite overpass is characterized by the absence of a significant surface UHI (SUHI) signal, corresponding to the period of the day when the urban-rural air temperature difference is typically negative. Conversely, nocturnal high-resolution LST data is rarely available. In this study, an energy balance-based machine learning approach is explored, considering the Local Climate Zones (LCZ), to describe the daily cycle of the heat flux components and predict the nocturnal SUHI, during an HW event. While the urban and rural spatial outlines are not visible in the diurnal thermal image, they become apparent in the latent and storage heat flux maps – built-up infrastructures uptake heat during the day which is released back into the atmosphere, during the night, whereas vegetation land surfaces loose diurnal heat through evapotranspiration. For the LST prediction model, a random forest (RF) approach is implemented. RF results show that the model accurately predicts the LST, ensuring mean square errors inferior to 0.1 K. Both the latent and storage heat flux components, together with LCZ classification, are the most important explanatory variables for the nocturnal LST prediction, supporting the adoption of the energy balance approach. In future research, other locations and time-series data shall be trained and tested, providing an efficient local urban climate monitoring tool, where in-situ air temperature observations are not available.
- Annual summaries dataset of Heatwaves in Europe, as defined by the Excess Heat FactorPublication . Oliveira, Ana; Lopes, António; Correia, EzequielThe dataset includes six yearly time series of six Heatwave (HW) aspects/metrics (or statistical summaries) calculated from the E-OBS dataset (v19eHOM, available in https://www.ecad.eu/download/ensembles/downloadversion19.0eHOM.php) following the Excess Heat Factor (EHF) methodology implemented in the ClimPACT tool, in compliance with the guidelines established by the Expert Team on Climate Change Detection and Indices (ET-SCI). These aspects correspond to annual summaries of HW frequency, duration and intensity, considering solely the events occurring during the extended summer season (from June to September). Input Daily Maximum (TX) and Minimum (TN) near-surface air temperature data were retrieved from a European gridded dataset (E-OBS) – the ensemble homogenized version ‘19.0eHOM’, at 0.1° × 0.1° spatial resolution, covering the European region, and retrieved from the EU-FP6 project UERRA (http://www.uerra.eu) and the Copernicus Climate Change Service. The E-OBS dataset is based on station observations, provided by the European Climate Assessment & Dataset. The here-presented HW aspects/summaries outputs of the ClimPACT tool correspond to the gridded annual statistical summaries of HW – these are detected based on the positive Excess Heat Factor (EHF) days, an HW index based on the human health response to heat extremes. The summaries include: (i) annual Number of Heatwaves (HWN); (ii) annual Heatwave Days Frequency (HWF); (iii) annual Maximum Heatwave Duration (HWD); (iv) annual Mean Heatwave Magnitude (HWM); and (v) annual Maximum Heatwave Amplitude (HWA). In addition, the annual maximum Heatwave Severity (HWS) was calculated, by dividing HWA by the 85th percentile of the positive EHF days. These annual time series can be used in HW-related studies focusing on the European region, particularly those focusing on climatology, trends, and impacts on human health.
- Apoio à distância a vítimas de violência e crime - Manual para profissionaisPublication . Soeiro, Cristina (coord.); Oliveira, Ana; Cotrim, Daniel; Almeida, Iris; Santos, Manuela; Ribeiro, Rita; Saavedra, Rosa; Caridade, Sónia
- Bronchodilator reversibility : what are the differences between asthma and chronic obstructive pulmonary disease?Publication . Barros, Raquel; Camões De Araújo, Patrícia; Mourato, Cláudia; Budzak, Khrystyna; Oliveira, Ana; Bárbara, CristinaIntroduction: Currently, the bronchodilator reversibility is not recommended to differentiate asthma from chronic obstructive pulmonary disease (COPD); however, physiopathological specificities of each disease contribute to the differences in response to the drug. Objectives: The objective of this study is to evaluate the differences in bronchodilator response between asthmatic and COPD patients and to determine which of the bronchodilation criteria have the best ability to detect the positive response in these patients. Materials and methods: This was a cross-sectional study. The sample included 104 patients with asthma or COPD who performed lung function tests between January and March 2018. The whole sample was analyzed according to postbronchodilator variation (Δ) of lung function parameters, and the postbronchodilator reversibility was characterized using a multiple bronchodilation criteria. The drug used in reversibility test was salbutamol. Results: In this study, Δ forced-expiratory volume in the 1st s (ΔFEV1) and a Δ Raw was statistically higher in the group with asthma compared with the group with COPD. In the asthma group, the criteria ↓ functional residual capacity (FRC) ≥10%, ↓Raw ≥ 35%, ↑ forced expiratory flow between 25% and 75% of vital capacity (FEF25%–75%) ≥20% and ↑ FEV1 and / or ↑ forced vital capacity ≥12% and 200 mL were those that presented a greater capacity of detecting a positive response to bronchodilator. The criteria ↑ FEF25%–75%≥20% and ↓ FRC ≥ 10% were those that had the greater ability of detecting airway reversibility in COPD group. Conclusion: The analysis of postbronchodilator FEV1 and raw modifications as well as the using of a combination of multiple bronchodilation criteria contribute to a deeper characterization of bronchodilator reversibility in asthma and COPD.
- Chemical Characterization and Bioactivity of Commercial Essential Oils and Hydrolates Obtained from Portuguese Forest Logging and ThinningPublication . Ruas, Ana; Graça, A.; Marto, Joana; Gonçalves, Lídia; Oliveira, Ana; Silva, Alexandra Nogueira da; Pimentel, Madalena; Moura, Artur Mendes; Serra, Ana Teresa; Figueiredo, Ana Cristina; Ribeiro, HelenaEssential oils (EOs) and hydrolates (Hds) are natural sources of biologically active ingredients with broad applications in the cosmetic industry. In this study, nationally produced (mainland Portugal and Azores archipelago) EOs (11) and Hds (7) obtained from forest logging and thinning of Eucalyptus globulus, Pinus pinaster, Pinus pinea and Cryptomeria japonica, were chemically evaluated, and their bioactivity and sensorial properties were assessed. EOs and Hd volatiles (HdVs) were analyzed by GC-FID and GC-MS. 1,8-Cineole was dominant in E. globulus EOs and HdVs, and α- and β-pinene in P. pinaster EOs. Limonene and α-pinene led in P. pinea and C. japonica EOs, respectively. P. pinaster and C. japonica HVs were dominated by α-terpineol and terpinen-4-ol, respectively. The antioxidant activity was determined by DPPH, ORAC and ROS. C. japonica EO showed the highest antioxidant activity, whereas one of the E. globulus EOs showed the lowest. Antimicrobial activity results revealed different levels of efficacy for Eucalyptus and Pinus EOs while C. japonica EO showed no antimicrobial activity against the selected strains. The perception and applicability of emulsions with 0.5% of EOs were evaluated through an in vivo sensory study. C. japonica emulsion, which has a fresh and earthy odour, was chosen as the most pleasant fragrance (60%), followed by P. pinea emulsion (53%). In summary, some of the studied EOs and Hds showed antioxidant and antimicrobial activities and they are possible candidates to address the consumers demand for more sustainable and responsibly sourced ingredients.
- Effect of modified atmosphere on polyphenols during storage of pasteurised strawberry pureesPublication . Oliveira, Ana; Alexandre, Elisabete M.C.; Coelho, Marta; Gomes, Maria Helena; Almeida, Domingos P.F.; Pintado, ManuelaThe minimum loss of processed fruit nutritional quality must been guaranteed during storage and the atmosphere can be a limiting step. Strawberry pur ees flushed with gas mixtures: 10 kPa O2 þ 90 kPa N2, 100 kPa N2 and air (78 kPa N2 þ 21 kPa O2 þ 0.03 kPa CO2) were stored for 90 days at 4 and 23 C and revealed no effect in total antioxidant activity and in total phenolic content. The compounds (þ)-catechin, ( )-epicatechin and quercetin-3-rutinoside were not affected by the atmospheres for both temperatures and ellagic acid was the exception within strawberry phytochemicals, where its concentration was higher for samples stored in air. Total anthocyanin content was better preserved when strawberry pur ee was stored in 100 kPa N2 at 4 and 23 C, at which temperatures their levels decreased 24 and 77%, respectively. At 4 C cyanidin-3- glucoside presented no significant differences between atmospheres. Pelargonidin-3-glucoside and pelargonidin-3-rutinoside decreased both 27% for 100 kPa N2 and 45% for 10 kPa O2 and air. All the individual anthocyanins were not affected by the atmospheres when stored at 23 ºC.
- Evaluation of telemonitoring of continuous positive airway pressure therapy in obstructive sleep apnoea syndrome : TELEPAP pilot studyPublication . Fernandes, Manuel; Antunes, Catarina; Martinho, Cristina; Carvalho, João; Abreu, Tiago; Oliveira, Ana; Pinto, Paula; Bárbara, CristinaIntroduction: Continuous positive airway pressure is an effective treatment for obstructive sleep apnoea syndrome. However, positive airway pressure compliance rates are disappointingly low, so effective interventions are needed to improve compliance in sleep apnoea. Telemonitoring has been used to improve compliance, but results have been inconsistent. This study aimed to determine outcomes of telemonitoring positive airway pressure compliance and efficacy data compared to usual care and phone-call care. Methods: Randomized controlled study in which 51 patients (82.4% male; between 25 and 78 years), diagnosed with moderate to severe obstructive sleep apnoea were consecutively randomized to usual care, weekly phone-call care or telemonitored care with the use of Restraxx™. All patients were submitted to a comprehensive educational programme during positive airway pressure adaptation. Patients were followed for the first four weeks of treatment with automatic positive airway pressure (AutoSet Spirit S8®; ResMed), and compliance and efficacy data were analyzed. Results: Telemonitored care group used automatic positive airway pressure an average of 5.0 ± 1.8 hours/night, usual care patients 5.1 ± 2.5 hours and phone-call care patients 3.9 ± 2.6 hours. The residual Apnoea--Hypopnoea Index was 5.3 ± 3.0 in telemonitored care, 5.0 ± 2.5 in usual care and 5.6 ± 3.8 in phone-call care. No statistically significant differences were found between groups regarding positive airway pressure compliance or efficacy (p = 0.296 and p = 0.825, respectively). Discussion: In the presence of a comprehensive educational programme during positive airway pressure adaptation, telemonitoring patients did not show benefits concerning compliance and efficacy. A larger follow-up period is needed to evaluate the long-term results of a telemonitoring programme.
- Excess Heat Factor climatology, trends, and exposure across European Functional Urban AreasPublication . Oliveira, Ana; Lopes, António; Soares, AmílcarIn Europe, regional climate change prospects indicate the urgency of adapting to extreme weather events. While increasing temperature trends have already been detected, in the last decades, the adoption of a European heatwave (HW) early-warning index is not yet consensual, partially due to the significant number of alternative algorithms, in some cases adjusted to the measurement of sector-specific impacts (as per the Expert Team on Climate Risk and Sector-specific Indices (ET-SCI)). In particular, the Excess Heat Factor (EHF) has been shown to accurately predict heat-related human health outcomes, in mid-latitude climates, provided that local summer exposure to excess heat is mostly driven by extreme air temperatures, with a lower contribution from relative humidity. Here, annual summaries of EHF-based HW detection were calculated for the European region, using daily maximum and minimum temperatures from the homogenised version of the E-OBS gridded dataset. Annual HW frequencies, duration, mean magnitude, maximum amplitude, and severity were subject to climatology and trend analysis across the European biogeographical regions, considering the 1961–1990 period as the baseline reference for anomaly detection in the more recent (1991–2018) decades. As HW-dependent morbidity/mortality affects mostly the elderly, an EHF-based HW Exposure Index was also calculated, by multiplying the recent probability of severe events per the number of people aged 65, or more, in the European Functional Urban Areas (FUAs). Results show that recent historical EHF-based patterns diverge across European Biogeographical regions, with a clear latitudinal gradient. Both the historical mean and recent trends point towards the greater exposure in the southern European Mediterranean region, driven by the significant increase of HW frequency, duration and maximum severity, especially in the last 3 decades; conversely, annual maximum EHF intensities (i.e., greatest deviations from the local 90th daily mean temperature) are mostly found in the northern and/or high altitude Boreal, Alpine and Continental regions, as a consequence of the latitudinal effect of local climatology on the HWM/HWA indices (this also translates into greater magnitudes of change, in this regions). Nonetheless, by simultaneously considering the probability of Severe HW occurrence in the last three decades, together with the log transformation of people aged 65 or more, results show that greater HW Exposure Indices affect FUAs across the whole Europe, irrespective of its regional climate, suggesting that more meaningful vulnerability assessments, early warning and adaptation measures should be prioritized accordingly.