Browsing by Issue Date, starting with "2020-08"
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- Spatial and Temporal Trends of Burnt Area in Angola: Implications for Natural Vegetation and Protected Area ManagementPublication . Catarino, Silvia; Romeiras, Maria M.; Figueira, Rui; Aubard, Valentine; Silva, João M. N.; Pereira, José M. C.Fire is a key driver of natural ecosystems in Africa. However, human activity and climate change have altered fire frequency and severity, with negative consequences for biodiversity conservation. Angola ranks among the countries with the highest fire activity in sub-Saharan Africa. In this study, we investigated the spatial and temporal trends of the annual burnt area in Angola, from 2001 to 2019, and their association with terrestrial ecoregions, land cover, and protected areas. Based on satellite imagery, we analyzed the presence of significant trends in burnt area, applying the contextual Mann–Kendall test and the Theil–Sen slope estimator. Data on burnt areas were obtained from the moderate-resolution imaging spectroradiometer (MODIS) burnt area product and the analyses were processed in TerrSet. Our results showed that ca. 30% of the country’s area burned every year. The highest percentage of annual burnt area was found in northeast and southeast Angola, which showed large clusters of decreasing trends of burnt area. The clusters of increasing trends were found mainly in central Angola, associated with savannas and grasslands of Angolan Miombo woodlands. The protected areas of Cameia, Luengue-Luiana, and Mavinga exhibited large areas of decreasing trends of burnt area. Conversely, 23% of the Bicuar National Park was included in clusters of increasing trends. Distinct patterns of land cover were found in areas of significant trends, where the clusters of increasing trends showed a higher fraction of forest cover (80%) than the clusters of decreasing trends (55%). The documentation of burnt area trends was very important in tropical regions, since it helped define conservation priorities and management strategies, allowing more effective management of forests and fires in countries with few human and financial resources.
- Best practice of risk modelling in motor insurance : using GLM and Machine Learning approachPublication . Xu, Zhifeng; Silva, João Andrade e; Chiong, ClaytonO pricing na atividade seguradora está a tornar-se cada vez mais interessante e desafi- ador pelo facto de a dimensão dos dados a analisar estar a crescer de forma explosiva. Torna-se assim urgente para as seguradoras reconsiderar a forma de lidar com este vol- ume de dados. Para implementar modelos sofisticados de pricing para produtos de seguro automóvel, aplicámos técnicas de machine learning, incluindo modelos GLM penalizados e métodos de boosting, que ajudam a identificar as características mais importantes de entre uma grande quantidade de variáveis candidatas. Estes métodos também permitem detetar potenciais interações sem testar as inúmeras combinações bidimensionais. Para um uso eficiente desses métodos, é necessário compreender o objetivo do modelo, as hipóteses que o suportam e dominar as metodologias estatísticas. Embora haja alguma evidência de um maior poder preditivo dos modelos baseados em machine learning quando comparados com os tradicionais GLM, estes últimos beneficiam de uma estrutura, mais conveniente e mais interpretável. O modelo GLM é mais fácil de ex- plicar às partes interessadas o que nos levou a utilizar os GLM na modelação do risco, mas absorvendo os ensinamentos dados pelos modelos de machine learning. A avaliação dos modelos é realizada pela análise dos resíduos quer na fase de treino quer de validação quer ainda de teste. Após a revisão pela equipa, aplicam-se alguns ajustes em cada modelo para reforçar a sua significância e a sua robustez. Espera-se que eles tenham alto poder preditivo nos dados fora da amostra e possam, portanto, ser usados no futuro.
- Of Wind and the Other: Literary Journalism by a Portuguese Female Travel WriterPublication . Baltazar, Raquel; Amorim, RitaRaquel Ochoa is a contemporary Portuguese writer who is deeply passionate about traveling and writing. This study analyzes her 2008 book, O Vento dos Outros (The wind of others), a series of travel crónicas across Central and South America, with the aim of situating Ochoa within Portuguese literary journalism. For six months, the author drifted aimlessly from the Andes in Costa Rica to Patagonia in Argentina, describing the theatre of reality from a sentimental woman’s perspective. Ochoa, a travel writer who immersed herself to meet the Other, uses “their winds” to reveal alterity. In a literary and subjective style, Ochoa reveals Latin American landscapes as well as detailed personal encounters and adventures with real people through an exploration of the senses and emotions. Moreover, her critical portrayal of the social plight of the Latin American peoples, a by-product of colonization and globalization, confers Ochoa a place in Portuguese literary journalism.
- Minor sternum and vertebral column congenital defects in Lisbon Identified Skeletal CollectionPublication . Amoroso, AlexandraThis study has mainly a descriptive aim, in which crude prevalence of minor skeletal congenital defects is calculated and sex differences are tested. Prevalence is compared with other studies to recognize regional patterns. Association with age-at-death and year-of-birth is tested to identify impact of environmental stress on minor congenital defects presence. Testing association between defects will identify defects with a probable identical etiology. Chi-square was used to identify sex differences, between studies differences, and to test relationships between defects and Spearman correlation to verify correlation intensity. T-test was used to test age-at-death and year-of-birth differences in defects prevalence. There were no statistically significant differences in prevalence of minor skeletal defects for sex and age-at-death. There were statistically significant differences in year-of-birth for sternal aperture and pectus excavatum (crude prevalence was higher for those who were born earlier). There was a statistical significant association between pectus excavatum and manubrium mesosternal joint and atlas posterior/lateral bridging and notochord defects. For most defects, this study has lower prevalence than other studies. From 18 minor axial skeletal congenital defects analyzed, prevalence ranges from absent to 26.3 (notochord defects). Pectus excavatum and manubrium mesosternal joint might have a similar etiology as well as atlas posterior/lateral bridging and notochord defects. This study has lower prevalence, for almost all defects, than other studies. None of the minor congenital defects tested might, at this time, be considered useful stress markers.
- Terror and its fiscal consequencesPublication . Clements, Benedict; Gupta, Sanjeev; Jalles, João Tovar; Khamidova, SaidaWe explore the impact of major terrorism shocks on macroeconomic and fiscal variables´ dynamics using an unbalanced panel of 191 heterogeneous countries from 1970 to 2018. By means of the local projection method, we find that a terrorist shock lowers a country’s real GDP as well as government tax revenues and raises debt-to-GDP ratio. The composition of government spending shifts in favor of military spending. Low-income countries are affected more than both emerging market and advanced economies. Our results are robust to a battery of sensitivity and robustness tests.
- Insights into Contemporary Portuguese Literary Journalism: The Crónicas of José Luís PeixotoPublication . Amorim, Rita; Baltazar, RaquelThis essay analyzes the crónicas of José Luís Peixoto, a contemporary Portuguese writer and journalist. Peixoto uses the first-person singular and plural to immerse himself for weaponized narrative in the service of a stronger social realism. Full of intimacies that accentuate feelings and emotions, Peixoto’s crónicas draw a vivid picture of the current plight of Portuguese people in the twenty-first century, raise awareness to their harsh social conditions, and cast criticism on the ineffectiveness of politicians who are generally considered the culprits for the enduring financial crisis. Writing in a rich poetic, yet realistic style, Peixoto deals with issues of poverty, aging, and the passing of time, the inevitability of death, and the incalculable loss of family and friends. Offering a humanistic analysis of the Portuguese identity, his crónicas are everyday, real-life encounters intertwined with rich imagery of local places and peoples, smells, and colors. Peixoto’s detailed personal descriptions of the social, cultural, and political environment reveal a literary and subjective nature that is as if the reader were inside the writer’s mind.
- A Vision of Empire: Irish Home Rule, the Scramble for Africa, and Portuguese Literary JournalismPublication . Soares, IsabelIrish Home Rule, a measure of Irish self-rule, was a heated political and humanitarian issue throughout the nineteenth century. If, historically, Ireland was one of the constituent nations of the United Kingdom, pro–Irish Victorian perspectives and twenty-first century hindsight show it was administered as a colony. In the late 1800s, the British Parliament conceded to discuss Home Rule for Ireland. This happened at a time when the British Empire, (in)famously styled as the empire on which the sun never set, for expansionist purposes was encroaching on Portugal’s African possessions and thus stressing Anglo-Portuguese diplomatic relations. In this scenario, two Portuguese consuls, who also served as press correspondents from Britain, used their journalistic voices to bring to light, for audiences on both sides of the Portuguese-speaking Atlantic, what they considered the truth behind British imperialism. Through the late nineteenth-century “new” journalism, a pioneering form of literary journalism, these diplomats-turned-unconventional-journalists were among the first critics of formal imperialism. As pieces of literary journalism, their articles on the question of Irish Home Rule are documents of historical meaning, revealing an underlying intention of creating public awareness of the dangers of the British will to imperial dominance, for which Ireland provided an example of territorial occupation and autocratic administration. Their reading of the Irish Question gives evidence that, even at its earliest stages, literary journalism is a journalism of concern about the Other and their plight.
- Income and wealth inequality : analyses of monetary policy channels rolePublication . Silva, Tomás Neves Henrique; Alves, JoséO objetivo do trabalho é analisar a relação entre política monetária e seus canais de transmissão para a desigualdade de renda e de riqueza nos países da zona do Euro. Nós analisamos três dos principais canais identificados pela literatura (Earnings Heterogeneity, Portfolio Composition e Income Composition) que possam explicar como as decisões de política monetária podem afetar as distribuições de renda e riqueza. No nosso trabalho empírico também incluímos uma regressão conjunta com todas as nossas variáveis explicativas com o objetivo de entender o impacto dos canais supracitados de forma combinada.
- Scholar-Practitioner Q+A . . . An Interview with Susana Moreira MarquesPublication . Trindade, Alice; Nery, IsabelSusana Moreira Marques was born in Porto, northern Portugal, in 1976, and currently lives in Lisbon. She worked for the BBC World Service and lived in Great Britain for a number of years, where her work was published in newspapers such as the Guardian. Her career as an author—the designation she likes to use for people who engage in writing, as it is the term that puts aside any differences between journalist and writer—has undergone different phases. She has worked for national newspapers such as Público and Jornal de Negócios, and more recently she has been with the Portuguese national public radio, RDP, where she hosts a weekly crónica. Moreira Marques’s work with the BBC until 2011 allowed her the freedom to research and reach different publics and outlets in places as varied as Hong Kong and Australia. Moreira Marques is a person whose demeanor is as graceful and observant as her writing. Elegant and delicate, she produces powerful texts based on information acquired through immersion research, handling difficult top ics such as migrants’ rights, sickness, and death, as well as easygoing texts that can be read on her blog, Bay Window,1 which she wrote for two years about her experiences while living in London. As an observer, her gaze comes from the outside, but she allows her senses and feelings to gather impressions that allow her to write within her own construction of mood. While all writing involves making a wide range of choices, Moreira Marques’s reflects the deli cateness of topics and her own response to them. In her point of view Moreira Marques is exact, yet unobtrusive. Characters and stories appear in a manner that neither imposes on them nor on the reader. The latter has the freedom to read and interpret at will, and the former are handled with respect for their individuality. The stories always have an author’s touch in the ordering and rendering of events and, invariably, they become Moreira Marques’s stories. Isabel Nery and Alice Trindade interviewed Moreira Marques at her home in Lisbon, on April 9, 2018.
- Lusophone Literary JournalismPublication . Soares, Isabel; Trindade, Alice