47 research outputs found
Ignition delay of reactivity controlled compression ignition (RCCI) for the mixture of diesel fuel and ethanol in a rapid compression machine / Atraso de ignição de ignição por compressão controlada de reatividade (RCCI) para a mistura de combustível diesel e etanol em uma máquina de compressão rápida
The power generation, used to promote comfort, mobility and others continually grows. To solve this growing demand, efforts have been directed towards the development of new energy sources, preferably renewable, and better ways of energy conversion by increasing the processes efficiencies. A good example of this is the gradual shift from conventional and highly inefficient vehicles, being replaced by hybrids or purely electrics. But even with gradual migration for more efficient energy use, we will continue depending of traditional fuels therefore it is necessary to develop more efficient and less polluting ways to use these sources. Thus, this work aims to study alternative ways of converting energy contained in fuels used in internal combustion engines by use of combustion mode RCCI, two fluids with different cetane numbers are introduced into the combustion chamber at different times with the purpose of burning the fuel with lower cetane number. Therefore, for combustion mode RCCI, the SOI of fuel with lower enthalpy of vaporization and the start of combustion must be determined to determine the ignition delay. The results show the ignition delays for the different techniques of injection of fuels with compression ratios of 16:1 and 20:1
Noite de terror na cidade luz: os atos terroristas em Paris e a avaliação da imagem de destino por turistas brasileiros
Contemporary terrorism may be considered one of the ills of the 21st century and its actions have reached an increasing number of non-combatant targets. The extremist groups are looking for places with large circulation of people as sights to carry out their attacks. The attacks aim to reach a greater number of kafirs, term to define the unbelievers or infidels of the Islamic doctrine, or to obtain a greater attention of the media. Thus, the present study aimed to understand how Brazilian tourists, who were in Paris, perceive the interference of the night of the attacks in November 2015 in the tourist image of the city. The research was qualitative with the triangulation of data: documentary research, open questionnaires and testimonials in videos, with the use of content analysis. The results show a medium impact on tourism activity, but little importance in the image of the city of Paris in the months following the attacks, with the flow of visitors reestablished in the short term. The primary relevance of this article was to understand the impact on tourist demand after terrorist attacks from the perception of tourists under the image of the destination.El terrorismo contemporáneo puede ser considerado uno de los males del siglo XXI y sus acciones han alcanzado un número cada vez mayor de blancos no combatientes. Los grupos extremistas están buscando lugares con gran circulación de personas como puntos turísticos para realizar sus ataques. Los atentados anhelan alcanzar un mayor número de kafirs, término para definir a los incrédulos o infieles de la doctrina islámica, o obtener una mayor atención de los medios. Así, el presente estudio tuvo como objetivo entender cómo los turistas brasileños, que se encontraban en París, perciben la interferencia de la noche de los atentados en noviembre de 2015 en la imagen turística de la ciudad. La investigación fue cualitativa con la triangulación de los datos: investigación documental, cuestionarios abiertos y testimonios en videos, con el uso del análisis de contenido. Los resultados muestran un impacto mediano en la actividad turística, pero poco importante en la imagen de la ciudad de París en los meses posteriores a los atentados, siendo el flujo de visitantes restablecido a corto plazo. La relevancia primordial de este artículo fue comprender el impacto en la demanda turística post-atentados terroristas a partir de la percepción de los turistas bajo la imagen del destino.O terrorismo contemporâneo pode ser considerado um dos males do século XXI e suas ações têm atingido um número cada vez maior de alvos não combatentes. Os grupos extremistas estão à procura de lugares com grande circulação de pessoas como pontos turísticos para realizar os seus ataques. Os atentados almejam alcançar um maior número de kafirs, termo para definir os incrédulos ou infiéis da doutrina islâmica, ou obter uma maior atenção da mídia. Assim, o presente estudo objetivou entender como turistas brasileiros, que estavam em Paris, percebem a interferência da noite dos atentados em 13 e 14 de novembro de 2015 na imagem turística da cidade. A investigação foi qualitativa exploratória com a triangulação dos dados: pesquisa documental, questionários abertos e depoimentos em vídeos, com o uso da análise de conteúdo. Os resultados mostram um impacto mediano na atividade turística, porém pouco importante na imagem da cidade de Paris nos meses subsequentes aos atentados, sendo o fluxo de visitantes reestabelecido em curto prazo. A relevância primordial deste artigo foi compreender o impacto na demanda turística pós-atentados terroristas a partir da percepção dos turistas sob a imagem do destino
Uma discussão sobre atividades de monitoria: estudo de caso da disciplina metrologia da FEM/UFPA
Este trabalho tem como objetivo apresentar a atividade de monitoria ministrada no ano de 2019 na disciplina de Metrologia para a turma do segundo semestre do curso de engenharia mecânica da Universidade Federal do Pará, e também discutir como a atividade de monitoria foi avaliada pelos alunos. O processo de ensino foi dividido em três fases, atividades teóricas, simuladas e práticas. Ao final do curso, foi elaborado um formulário online com 5 questões com o objetivo de saber como a monitoria foi compreendida pelos alunos acompanhados. O formulário foi disponibilizado por meio de uma extensão da plataforma Google. O procedimento avaliativo dividido em três etapas, teórica, simulada e prática, proporcionou uma visão ampla de como ocorre gradativamente a absorção do que é ensinado aos alunos. Observou-se a interação através da forma que os alunos monitorados tiveram uma boa experiência de ensino/aprendizagem proporcionada pela presença do monitor em sala de aula. Um monitor é fundamental para ampliar a disseminação do conhecimento que é repassado do professor para o aluno-monitorado
Uma discussão sobre atividades de monitoria: estudo de caso da disciplina metrologia da FEM/UFPA
Este trabalho tem como objetivo apresentar a atividade de monitoria ministrada no ano de 2019 na disciplina de Metrologia para a turma do segundo semestre do curso de engenharia mecânica da Universidade Federal do Pará, e também discutir como a atividade de monitoria foi avaliada pelos alunos. O processo de ensino foi dividido em três fases, atividades teóricas, simuladas e práticas. Ao final do curso, foi elaborado um formulário online com 5 questões com o objetivo de saber como a monitoria foi compreendida pelos alunos acompanhados. O formulário foi disponibilizado por meio de uma extensão da plataforma Google. O procedimento avaliativo dividido em três etapas, teórica, simulada e prática, proporcionou uma visão ampla de como ocorre gradativamente a absorção do que é ensinado aos alunos. Observou-se a interação através da forma que os alunos monitorados tiveram uma boa experiência de ensino/aprendizagem proporcionada pela presença do monitor em sala de aula. Um monitor é fundamental para ampliar a disseminação do conhecimento que é repassado do professor para o aluno-monitorado
SARS-CoV-2 reinfection caused by the P.1 lineage in Araraquara city, Sao Paulo State, Brazil
Reinfection by the severe acute respiratory syndrome coronavirus type 2 (SARS-COV-2) has been reported in many countries, suggesting that the virus may continue to circulate among humans despite the possibility of local herd immunity due to massive previous infections. The emergence of variants of concern (VOC) that are more transmissible than the previous circulating ones has raised particular concerns on the vaccines effectiveness and reinfection rates. The P.1 lineage was first identified in December 2020 in Manaus city and is now globally spread. We report the first case of reinfection of SARS-CoV-2 caused by the P.1 variant outside of Manaus. The potential of these new variants to escape naturally and vaccine- induced immunity highlights the need for a global vigilance
O Futuro do turismo no Brasil a partir da análise crítica do período 2000-2019
This article provides a perspective on tourism in Brazil, analyzing the main developments focusing on the period 2000-2019. This opinion paper provides a reflection made by academics with expertise in tourism in Brazil. Tourism-related topics covered in this paper include economics, politics and planning, marketing, transportation, environment, gastronomy, hospitality, leisure, among others. As the main conclusion, it is argued that Brazil has not managed to position itself as an internationally renowned destination. The efforts in the 1990s to support the development of regional tourism have had only moderate success. Economic crises, political instability, violence and corruption were obstacles that considerably affected the tourism sector. The lack of a coordinated approach between the various levels of government, the shortage of tourism data and a long-term supra-governmental marketing campaign, among other factors, meant that the country missed several opportunities in the 2010s to become established as one of the top tourist destinations in the global market.El artículo ofrece una perspectiva del turismo en Brasil, analizando los principales desarrollos con un enfoque en el período 2000-2019. Es un artículo de opinión con reflexiones de investigadores del turismo brasileño. Los temas relacionados con el turismo que se tratan en este artículo incluyen economía, política y planificación, marketing, transporte, medio ambiente, gastronomía, hostelería, ocio, entre otros. Como conclusión principal, se considera que Brasil no ha logrado posicionarse como un destino de renombre internacional, ya que desde la década de los noventa los esfuerzos para apoyar el desarrollo del turismo regional solo han tenido un éxito moderado. Las crisis económicas, la inestabilidad política, la violencia y la corrupción fueron obstáculos que afectaron considerablemente al sector turístico. La falta de un enfoque coordinado entre los distintos niveles de gobierno, la escasez de datos turísticos y una campaña de marketing supra gubernamental a largo plazo, entre otros factores, hicieron que el país perdiera varias oportunidades importantes en la década de 2010 para establecerse como uno de los principales destinos turísticos del mercado mundial.O presente artigo oferece uma perspectiva sobre o turismo no Brasil, analisando os principais desdobramentos com foco no período de 2000-2019. Trata-se de um artigo de opinião com reflexões de acadêmicos do turismo brasileiro. Os tópicos relacionados ao turismo, cobertos neste artigo, incluem economia, política e planejamento, marketing, transporte, meio ambiente, gastronomia, hospitalidade, lazer, entre outros. Como principal conclusão, considera-se que o Brasil não conseguiu se posicionar como destino de renome internacional, já que desde a década de 1990 os esforços para apoiar o desenvolvimento do turismo regional obtiveram sucesso apenas moderado. As crises econômicas, a instabilidade política, a violência e a corrupção foram entraves que afetaram consideravelmente o setor de turismo. A falta de uma abordagem coordenada entre os vários níveis de governo, a escassez de dados de turismo e uma campanha de marketing supra-governamental de longo prazo, entre outros fatores, fizeram com que o país perdesse várias oportunidades importantes na década de 2010 para se estabelecer como um dos principais destinos turísticos no mercado global
Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019
Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens
ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest
Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ
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A social and ecological assessment of tropical land uses at multiple scales: the Sustainable Amazon Network
Science has a critical role to play in guiding more sustainable development trajectories. Here, we present the Sustainable Amazon Network (Rede Amazonia Sustentavel, RAS): a multidisciplinary research initiative involving more than 30 partner organizations working to assess both social and ecological dimensions of land-use sustainability in eastern Brazilian Amazonia. The research approach adopted by RAS offers three advantages for addressing land-use sustainability problems: (i) the collection of synchronized and co-located ecological and socioeconomic data across broad gradients of past and present human use; (ii) a nested sampling design to aid comparison of ecological and socioeconomic conditions associated with different land uses across local, landscape and regional scales; and (iii) a strong engagement with a wide variety of actors and non-research institutions. Here, we elaborate on these key features, and identify the ways in which RAS can help in highlighting those problems in most urgent need of attention, and in guiding improvements in land-use sustainability in Amazonia and elsewhere in the tropics. We also discuss some of the practical lessons, limitations and realities faced during the development of the RAS initiative so far.Keywords: Social–ecological systems, Tropical forests, Land use, Interdisciplinary research, Sustainability, Trade-off