Browsing by Issue Date, starting with "2019-08"
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- Calendarização das visitas dos artistas da operação nariz vermelho aos hospitaisPublication . Nabais, Raquel Nogueira; Pato, Margarida VazEste trabalho final de mestrado foi desenvolvido sob a forma de projeto, em parceria com a Operação Nariz Vermelho (ONV), estando o seu tema ligado à afetação dos artistas profissionais, Doutores Palhaços, da ONV às visitas a realizar aos vários hospitais, abrangidos pelo programa de visitas desta instituição, na região da Grande Lisboa. O objetivo deste projeto é facilitar a execução desta tarefa que, nos tempos que decorrem, é uma tarefa bastante morosa e trabalhosa para os colaboradores da ONV. Assim, e de forma a atingir todos os objetivos pensados pela instituição, foi de extrema importância, numa fase inicial, fazer o levantamento de todos as especificidades da calendarização das visitas. Depois, e recorrendo a estudos já realizados, foi formulado em Programação Linear Binária Mista um modelo de otimização capaz de gerar uma solução para dar resposta ao problema do planeamento das visitas. Adicionalmente, foi também desenvolvido um programa recorrendo ao uso da linguagem Visual Basic for Applications do Excel. Este é capaz de ler os dados do problema e colocá-los como parâmetros do software OpenSolver, executar o software de forma automática, escrever e estruturar a solução gerada com o intuito de possibilitar a análise e o uso desta pelos colaboradores da ONV.
- Equilíbrio entre mulheres e homens nos órgãos de governo das empresas cotadas em bolsa : a influência do compromisso estratégico empresarialPublication . Paço, Nuno Filipe Salgueiro do; Casaca, Sara FalcãoA segregação sexual vertical, entendida como a sub-representação de mulheres em cargos de direção nas organizações, é um fenómeno amplamente documentado na literatura sobre género e organizações. As causas são atribuídas a diversos fatores estruturais como, por exemplo, os estereótipos de género, os papéis tradicionalmente associados aos homens e às mulheres, assim como as representações sociais dominantes nas organizações acerca do perfil de trabalhador ideal. A superação deste fenómeno depende de um processo de mudança que vise a integração sistemática da igualdade entre mulheres e homens nas organizações. Esse processo deve envolver tanto a dimensão formal como a informal. Este estudo centra-se na primeira dimensão, visando compreender a importância do compromisso estratégico empresarial com a igualdade entre mulheres e homens na superação do fenómeno da segregação sexual vertical. Foi motivado pelo novo enquadramento normativo em vigor no país, desde 2018, que determina uma representação mínima de pessoas do sexo sub-representado nos cargos de administração e de fiscalização do setor público empresarial e das empresas cotadas em bolsa. Optou-se, por circunscrever a análise a este último segmento empresarial. Propomo-nos compreender em que medida o compromisso estratégico empresarial com a igualdade entre mulheres e homens pode ser considerado um antecedente organizacional facilitador da efetividade da Lei. Como principal conclusão, verificámos que existem fortes indícios de que o compromisso estratégico empresarial com a igualdade entre mulheres e homens seja relevante para o alcance de uma representação mais equilibrada de mulheres e homens nos órgãos de governo das empresas cotadas em bolsa em Portugal.
- Equity research - Impresa SGPS SAPublication . Carvalho, João Pedro Runa Ferreira de; Bastardo, CarlosA principal motivação na escolha da Impresa SGPS surge com os interessantes desafios a que esta empresa tem sido submetida numa era em que a indústria da Media passa por profundas transformações com a florescimento de novas plataformas proporcionadas pelos avanços tecnológicos. O objetivo foi realizar uma análise e avaliação da empresa, resultando na estimativa de um valor alvo, definindo os métodos de avaliação com a evolução do trabalho da maneira mais adequada, mantendo a estrutura CFA. Sendo o maior grupo de Media Português, o foco da sua atividade está principalmente dividido entre a televisão e a imprensa, onde se destacam a SIC e o Expresso, contribuindo para receitas de 172M€ em 2018. Para determinar o valor intrínseco do grupo, foi utilizada a abordagem de fluxos de caixa descontados (DCF) como método principal. Com um preço alvo estimado em 0,34€ por ação em Agosto de 2019, é emitida a recomendação de COMPRA com alto risco, representando um potencial de valorização de 37% desde o preço de enceramento de 1 de agosto, de 0,25€. Abordagens complementares de avaliação, testes de stress, incluindo análises de sensibilidade e de cenários com variáveis sensíveis, foram utilizadas para apoiar estes resultados de avaliação.
- Movement seasonality in a desert-dwelling bat revealed by miniature GPS loggersPublication . Conenna, Irene; López-Baucells, Adrià; Rocha, Ricardo; Ripperger, Simon; Cabeza, MarBackground Bats are among the most successful desert mammals. Yet, our understanding of their spatio-temporal dynamics in habitat use associated with the seasonal oscillation of resources is still limited. In this study, we have employed state-of-the-art lightweight GPS loggers to track the yellow-winged bat Lavia frons in a desert in northern Kenya to investigate how seasonality in a desert affects the a) spatial and b) temporal dimensions of movements in a low-mobility bat. Methods Bats were tracked during April–May 2017 (rainy season) and January–February 2018 (dry season) using 1-g GPS loggers. Spatial and temporal dimensions of movements were quantified, respectively, as the home range and nightly activity patterns. We tested for differences between seasons to assess responses to seasonal drought. In addition, we quantified home range overlap between neighbouring individuals to investigate whether tracking data will be in accordance with previous reports on territoriality and social monogamy in L. frons. Results We obtained data for 22 bats, 13 during the rainy and 9 during the dry season. Home ranges averaged 5.46 ± 11.04 ha and bats travelled a minimum distance of 99.69 ± 123.42 m/hour. During the dry season, home ranges were larger than in the rainy season, and bats exhibited high activity during most of the night. No apparent association with free water was identified during the dry season. The observed spatial organisation of home ranges supports previous observations that L. frons partitions the space into territories throughout the year. Conclusions Our results suggest that, in low-mobility bats, a potential way to cope with seasonally harsh conditions and resource scarcity in deserts is to cover larger areas and increase time active, suggesting lower cost-efficiency of the foraging activity. Climate change may pose additional pressures on L. frons and other low-mobility species by further reducing food abundances.
- Measuring strain caused by ion implantation in GaNPublication . Mendes, P.; Lorenz, K.; Alves, E.; Schwaiger, S.; Scholz, F.; Magalhães, S.
- Mercury in archaeological human bone: biogenic or diagenetic?Publication . Emslie, Steven D.; Alderman, Audrey; McKenzie, Ashley; Brasso, Rebecka; Taylor, Alison R.; Molina Moreno, María; Cambra-Moo, Oscar; González Martín, Armando; Silva, Ana Maria; Valera, António; García Sanjuán, Leonardo; Vijande Vila, EduardoWe investigated mercury (Hg) in human bone from archaeological sites in the Iberian Peninsula where the cultural use of cinnabar (HgS) as a pigment, offering or preservative in burial practices has been documented from the 4th to 2nd millennia cal B.C. (Late Neolithic, Copper Age and Bronze Age). Previous analyses have shown high levels of total mercury (THg) in human bone at numerous Neolithic and Chalcolithic sites in this region, but the question remains if this mercury entered the bones via diagenetic processes in the soil, especially where cinnabar powder and paint was found associated with the burials, or if it entered the bone via biogenic pathways from exposure to mercury from using cinnabar in life. We analyzed the humerus, femur, and tibia from a total of 30 individual burials from four Neolithic to Bronze Age sites in Iberia and found low to high values of THg in these bones, with the humerus showing significantly more THg concentrations than other skeletal elements when the THg was greater than 1 ppm. This pattern of Hg deposition in skeletal material from different sites and ages strongly suggests a biogenic origin for the mercury. In addition, absence of detectable Hg in bones with high to low values of THg using SEM EDS analysis further discounts diagenetic intrusion of Hg or cinnabar particles into the bone from the soil. It is likely that greater stress and bone remodeling rates from use of heavy tools and other activities in life are responsible for higher THg in the humerus than other skeletal elements, but additional research is needed to verify this.
- Serious mismatches continue between science and policy in forest bioenergyPublication . Norton, Michael; Baldi, Andras; Buda, Vicas; Carli, Bruno; Cudlin, Pavel; Jones, Mike B.; Korhola, Atte; Michalski, Rajmund; Novo, Francisco; Oszlányi, Július; Santos, F.D.; Schink, Bernhard; Shepherd, John; Vet, Louise; Walloe, Lars; Wijkman, AndersIn recent years, the production of pellets derived from forestry biomass to replace coal for electricity generation has been increasing, with over 10 million tonnes traded internationally—primarily between United States and Europe but with an increasing trend to Asia. Critical to this trade is the classification of woody biomass as ‘renewable energy’ and thus eligible for public subsidies. However, much scientific study on the net effect of this trend suggests that it is having the opposite effect to that expected of renewable energy, by increasing atmospheric levels of carbon dioxide for substantial periods of time. This review, based on recent work by Europe's Academies of Science, finds that current policies are failing to recognize that removing forest carbon stocks for bioenergy leads to an initial increase in emissions. Moreover, the periods during which atmospheric CO2 levels are raised before forest regrowth can reabsorb the excess emissions are incompatible with the urgency of reducing emissions to comply with the objectives enshrined in the Paris Agreement. We consider how current policy might be reformed to reduce negative impacts on climate and argue for a more realistic science-based assessment of the potential of forest bioenergy in substituting for fossil fuels. The length of time atmospheric concentrations of CO2 increase is highly dependent on the feedstocks and we argue for regulations to explicitly require these to be sources with short payback periods. Furthermore, we describe the current United Nations Framework Convention on Climate Change accounting rules which allow imported biomass to be treated as zero emissions at the point of combustion and urge their revision to remove the risk of these providing incentives to import biomass with negative climate impacts. Reforms such as these would allow the industry to evolve to methods and scales which are more compatible with the basic purpose for which it was designed.
- Ensuring access to high-quality resources reduces the impacts of heat stress on beesPublication . Vanderplanck, Maryse; Martinet, Baptiste; Carvalheiro, Luisa; Rasmont, Pierre; Barraud, Alexandre; Renaudeau, Coraline; Michez, DenisPollinators are experiencing declines globally, negatively affecting the reproduction of wild plants and crop production. Well-known drivers of these declines include climatic and nutritional stresses, such as a change of dietary resources due to the degradation of habitat quality. Understanding potential synergies between these two important drivers is needed to improve predictive models of the future effects of climate change on pollinator declines. Here, bumblebee colony bioassays were used to evaluate the interactive effects of heat stress, a reduction of dietary resource quality, and colony size. Using a total of 117 colonies, we applied a fully crossed experiment to test the effect of three dietary quality levels under three levels of heat stress with two colony sizes. Both nutritional and heat stress reduced colony development resulting in a lower investment in offspring production. Small colonies were much more sensitive to heat and nutritional stresses than large ones, possibly because a higher percentage of workers helps maintain social homeostasis. Strikingly, the effects of heat stress were far less pronounced for small colonies fed with suitable diets. Overall, our study suggests that landscape management actions that ensure access to high-quality resources could reduce the impacts of heat stress on bee decline.
- Flood fatalities in Europe, 1980–2018: variability, features, and lessons to learnPublication . Petrucci, Olga; Aceto, Luigi; Bianchi, Cinzia; Bigot, Victoria; Brázdil, Rudolf; Pereira, Susana; Kahraman, Abdullah; Kılıç, Özgenur; Kotroni, Vassiliki; Llasat, Maria Carmen; Llasat-Botija, Montserrat; Papagiannaki, Katerina; Pasqua, Angela Aurora; Řehoř, Jan; Rossello Geli, Joan; Salvati, Paola; Vinet, Freddy; Zêzere, José LuísFloods are still a significant threat to people, despite of the considerable developments in forecasting, management, defensive, and rescue works. In the near future, climate and societal changes as both urbanization of flood prone areas and individual dangerous behaviors could increase flood fatalities. This paper analyzes flood mortality in eight countries using a 39-year database (1980–2018) named EUFF (EUropean Flood Fatalities), which was built using documentary sources. The narratives of fatalities were investigated and standardized in the database reporting the details of the events. The entire dataset shows a stable trend on flood fatalities, despite the existence of individual increasing (Greece, Italy, and South France) and decreasing (Turkey and Catalonia) trends. The 2466 fatalities were mainly males, aged between 30–49 years and the majority of them happened outdoor. Most often people were dragged by water/mud when travelling by motor vehicles. Some cases of hazardous behaviors, such as fording rivers, were also detected. The primary cause of death was drowning, followed by heart attack. This work contributes to understand the human–flood interaction that caused fatalities. The changes in society’s vulnerability highlighted throughout this study contribute to manage future risks, to improve people protection actions, and to reduce risk behaviors.
- Killer whale genomes reveal a complex history of recurrent admixture and vicariancePublication . Foote, Andrew D.; Martin, Michael D.; Louis, Marie; Pacheco, George; Robertson, Kelly M.; Sinding, Mikkel‐Holger S.; Amaral, Ana Rita; Baird, Robin W.; Baker, Charles Scott; Ballance, Lisa; Barlow, Jay; Brownlow, Andrew; Collins, Tim; Constantine, Rochelle; Dabin, Willy; Dalla Rosa, Luciano; Davison, Nicholas J.; Durban, John W.; Esteban, Ruth; Ferguson, Steven H.; Gerrodette, Tim; Guinet, Christophe; Hanson, M. Bradley; Hoggard, Wayne; Matthews, Cory J. D.; Samarra, Filipa I. P.; de Stephanis, Renaud; Tavares, Sara B.; Tixier, Paul; Totterdell, John A.; Wade, Paul; Excoffier, Laurent; Gilbert, M. Thomas P.; Wolf, Jochen B. W.; Morin, Phillip A.Reconstruction of the demographic and evolutionary history of populations assuming a consensus tree-like relationship can mask more complex scenarios, which are prevalent in nature. An emerging genomic toolset, which has been most comprehensively harnessed in the reconstruction of human evolutionary history, enables molecular ecologists to elucidate complex population histories. Killer whales have limited extrinsic barriers to dispersal and have radiated globally, and are therefore a good candidate model for the application of such tools. Here, we analyse a global data set of killer whale genomes in a rare attempt to elucidate global population structure in a nonhuman species. We identify a pattern of genetic homogenisation at lower latitudes and the greatest differentiation at high latitudes, even between currently sympatric lineages. The processes underlying the major axis of structure include high drift at the edge of species' range, likely associated with founder effects and allelic surfing during postglacial range expansion. Divergence between Antarctic and non-Antarctic lineages is further driven by ancestry segments with up to four-fold older coalescence time than the genome-wide average; relicts of a previous vicariance during an earlier glacial cycle. Our study further underpins that episodic gene flow is ubiquitous in natural populations, and can occur across great distances and after substantial periods of isolation between populations. Thus, understanding the evolutionary history of a species requires comprehensive geographic sampling and genome-wide data to sample the variation in ancestry within individuals.