21 research outputs found
Late Holocene paleoenvironments of the floodplain of the Solimões River, Central Amazonia, based on the palynological record of Lake Cabaliana
The core PD-67 of 160 cm depth was collected from the delta of Lake Cabaliana situated on the Solimões River. Seventeen samples were removed for palynological and sedimentological analysis and three for radiocarbon analysis. Two dry periods, both in the Late Holocene, were observed (2800-2550 cal yr BP, 1450-550 cal yr BP) separated by a wetter phase (2550-1450 cal yr BP). In 2800-2550 cal yr BP, varzea forests of Alchornea, Symmeria, Cecropia, Alternanthera and Asteraceae were predominant. Beginning in 2,550-1450 cal yr BP, the varzea was characterized by pioneer elements, such as Cassia, Laetia, Mabea, Symmeria and Cecropia, and by the expansion of Poaceae, Cyperaceae, Sagittaria, Montrichardia and Asteraceae. In 1450-550 cal yr BP the succession of varzea continued with Pseudobombax, Laetia, Luehea/Lueheopsis and Ryanaea increasing simultaneously with the terra firme vegetation of Rutaceae, Sapotaceae, Styrax, Scleronema, Anthurium, Araceae, pteridophytes and Pariana. The successional dynamics at Lake Cabaliana indicated that the local varzea had become established recently, and is composed of a mosaic of different successional stages of vegetation influenced mainly by flood pulse and variation in rainfall. It is therefore possible to propose that the recent climate history of Central Amazonia reflects changes in rainfall patterns in the basin
Course “Girls with Science”: Potentials of Geology and Paleontology’s Popularization from a Gender Perspective
The Girls education course “Girls with science: Geology, Paleontology and Gender” hosted by Museu Nacional/UFRJ were
conceived by the idea that children and youth education in science should be focus on awake girls interest in science, once in the
actual initiatives the masculine participation is more frequent. The highest number of subscription in extended education courses
show how the society is interested in activities of continues education focus on gender identity. The course main objective is present to girls how science is developed by ordinary people and even in research areas where the male gender is predominant the women participation is growing. This article aims spread the work method used in the “Girls with science” course composed of theoretical and practical activities using day by day examples in Geology and Paleontology. Also, we expect encourage other institution in create, reproduce and development new activities for general audience. The work team is composed of professors, technical personal, undergraduate and postgraduate students in several different areas and is the one of the project highlights, once students have the chance of observed and see female scientist in careers different phases. The results show is necessary more interaction between highacademic education and school. Also, the focus on everyday activities that can improve the understanding of science is welcome.
Recently, the brand new course was award with the honorable mention in the 8º Ibero Americano award in Museum Education, andnow is part of the good habits database in education sustained by Ibermuseus
“Meninas com Ciência” vive e resiste pelo Museu Nacional / UFRJ
O curso de extensão “Meninas com Ciência” é uma ação concebida e executada pelas mulheres do Departamento de Geologia e Paleontologia do Museu Nacional (MN/UFRJ), voltado para alunas do 6º ao 9º ano do Ensino Fundamental, de escolas públicas e particulares. Ocorre desde 2017, em edições semestrais, com oficinas práticas e lúdicas em Geociências. Aqui, são apresentados o histórico do curso, as atualizações ao método, avaliações de acesso e permanência das alunas, além das perspectivas futuras. O objetivo deste trabalho é inspirar novas iniciativas, democratizando o acesso às ações de divulgação no país. Desde sua criação, o curso enfrentou diversos desafios; entre eles, a perda de toda a sua estrutura física, durante o incêndio do MN/UFRJ, mas a equipe persiste e, ao longo de seis edições, teve 2333 inscritas e ofertou 455 vagas. Além disso, é crescente o interesse de outras instituições em replicar o modelo. Até o momento, “Meninas com Ciência” inspirou, com sucesso, a execução de sete ações semelhantes nos estados de São Paulo, Distrito Federal e Pará, o que corrobora a receptividade da sociedade e a importância destas iniciativas voltadas às questões de gênero. Este trabalho demonstra que é possível realizar divulgação científica de qualidade e gratuita, mesmo sob condições adversas e com baixo orçamento. Ainda, traz os desafios em popularizar o acesso de meninas de diferentes condições, sociais e econômicas, ao curso. Em 2020, em virtude da pandemia do novo coronavírus, as duas edições previstas estão suspensas. Porém, a partir desta adversidade, “Meninas com Ciência” cresce e torna-se um projeto de extensão. Trata-se de uma estrutura maior e permanente, que abriga: a) o curso presencial, que será retomado assim que possível; b) um canal online direto com a sociedade, visando propor atividades, tirar dúvidas sobre Geociências, conversar sobre as experiências de mulheres cientistas, etc. e c) a criação de linhas de pesquisa em extensão
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Registros palinológicos em sedimentos deltaicos do Lago Cabaliana na planície aluvial do Rio Solimões, Amazônia Central - Brasil
A sediment core (PD-67) was collected in the alluvial plain of the Solimões river located at the varzea in Central Amazonia. A profile of 160 cm was raised from Lago Cabaliana delta and samples were prepared using standard pollen analytical techniques and acetolysis. Three sediment samples were dated by AMS-radiocarbon dates. The dates from the lower part of the sediment samples of Lago Cabaliana indicate an age of 2570 ± 40 14C yr BP, followed by an age of 1570 ± 40 14C yr BP and 830 ± 40 14C yr BP in the uppermost part At about 2600 14C yr BP Alchornea, Cecropia and Symmeria were predominant likewise the herbaceous elements: grasses, Asteraceae and Alternanthera. The presence of Arrabidaea, Rubiaceae, Tabebuia, Sapotaceae, Rutaceae, Protium and Symphonia implies a well-drained upland forest and adjacent wetlands, indicated by the presence of Sagittaria pollen and fern spores. At this period, the sedimentation was characterized by compact clay, and it indicates that the flood was probably much lower during this time interval. Cecropia has remained relatively constant since 2700 14C yr BP and later, around 2200 14C yr BP, showed an increase. Grasses and other herbaceous pollen show a slight fall, occurred around 2200 14C yr BP, and together with Byrsonima and other plants from late successional stages in the floodplain - Sapium and Myrtaceae we can infer a decrease in height water column. At 700 14C yr BP, the climax vegetation of varzea becomes predominant, despite the frequency of late secondary succession elements like Pseudobombax and Laetia. Pollen of Cassia, Vismia, Neoxythece and upland táxons: Doliocarpus, Simaba and Scleronema suggest the proximity or the mixture of elements from forest upland and varzea. There were two drier periods, represented by the effective decrease in precipitation around 2700 14C years BP and 1200 to 700 14C years BP. The other phases (2400 14C yr BP and from 1500 to 1200 14C yr BP) are indicative of less pronounced dry periods, i.e., small variations in the levels of flood in the basin. The succession dynamics occurring in the lake Cabaliana indicate that the varzea was recently established and is composed of a mosaic of different successional stages of vegetation, mainly controlled by the flood pulse. Alternating wet and dry phases caused by ENSO in the late Holocene were detected, increasing seasonality of precipitation. The drainage pattern of the Solimões River was affected, which caused fluctuations in the flood pulse and therefore variations in floristic composition of vegetation surrounding Lake Cabaliana and changes in depositional processes. Thus, it is possible to propose that the recent climate history of Central Amazon is a reflection of changes in precipitation patterns in the basin.O testemunho de sondagem (PD-67) foi obtido da planície aluvial do Rio Solimões, situado na área de várzea da Amazônia Central. Um perfil de 160 cm foi retirado do delta do Lago Cabaliana e submetido a análises sedimentológicas, palinológicas. Três amostras foram datadas pela técnica de Accelerator Mass Spectrometry (AMS). Foram detectadas idades do Holoceno superior, indicando aproximadamente 2570 ± 40 14C anos AP na base do testemunho, 1570 ± 40 14C anos AP (90 cm) e no topo, foi encontrada a idade de 830 ± 40 14C anos AP. Há cerca de 2600 14C anos AP, Alchornea, Symmeria e Cecropia foram predominantes, do mesmo modo que os elementos herbáceos, representando pelas gramíneas, Asteraceae e Alternanthera. A presença de Arrabidaea, Rubiaceae, Tabebuia, Sapotaceae, Rutaceae, Protium e Symphonia implicam em uma floresta de terra firme drenada e áreas adjacentes pantanosas, indicado pela presença de pólen de Sagittaria e esporos de pteridófitas. Nesta fase, a sedimentação predominante foi de material argiloso, referente à fase de inundação, sugerindo que a cheia foi possivelmente muito menor neste intervalo de tempo. Cecropia se manteve relativamente constante desde 2700 14C anos AP e posteriormente, há cerca de 2200 14C anos AP, apresentou um aumento. Pólen de gramíneas e outras herbáceas apresentam uma ligeira queda, ocorrida também há cerca de 2200 14C anos AP e juntamente com a presença de Byrsonima e outras plantas de estágios sucessionais tardios da várzea, como Sapium e Myrtaceae, pode-se inferir que houve diminuição na altura da coluna d´água. Há 700 14C anos AP, a vegetação climácica da várzea começa a se tornar predominante, apesar das maiores freqüências de plantas de sucessão secundária tardia representados por Pseudobombax e Laetia. Pólen de Cassia, Vismia e Neoxythece e de táxons de terra firme: Doliocarpus, Simaba e Scleronema sugerem a proximidade ou a mistura de elementos de terra firme e várzea. Ocorreram dois períodos mais secos, representados pela efetiva diminuição da precipitação: cerca de 2700 14C anos AP e 1200 - 700 14C anos AP. As outras fases (2400 14C anos AP e 1500 - 1200 14C anos AP) são indicativas de períodos secos menos pronunciados, ou seja, pequenas variações nos níveis de inundação da bacia. A dinâmica sucessional ocorrida no lago Cabaliana, desta forma, indica que a várzea local se estabeleceu recentemente e é composta por um mosaico de diversos estágios sucessionais da vegetação, controlados principalmente pelo pulso de inundação. Foram detectadas alternância de fases úmidas e secas causadas pelo ENSO no Holoceno tardio, intensificando a sazonalidade da precipitação. O ciclo hidrológico do Rio Solimões foi influenciado, o que acarretou flutuações no pulso de inundação e conseqüentemente variações na estrutura e composição florística da vegetação circundante do Lago Cabaliana e alterações nos processos deposicionais. Assim, é possível propor que o a história climática recente da Amazônia Central é reflexo de mudanças nos padrões de precipitação na bacia
Miocene fern spores and pollen grains from the Solimões Basin, Amazon Region, Brazil
ABSTRACT This work documents fern spores and pollen grains (miospores) recovered from rocks of the Solimões Formation (Solimões Basin), their botanical affinities, ecology and distribution in the Miocene of the Amazon Region. The assemblage of miospores is well preserved and diverse. They are identified, illustrated and assigned to the ten families of ferns and 22 families of spermatophytes. All miospores were identified to the taxonomic level of species except for two taxa (Perinomonoletes and Podocarpidites). The families Pteridaceae and Arecaceae were most representative of ferns and spermatophytes, respectively. This work contributes to the knowledge of the paleoflora and will aid in paleoenvironmental, paleoecological and biostratigraphic interpretations of the Miocene of the Amazon Region
Evaluation of Marginal Sealing in Adhesives Restorations After the Use of a Papain Gel
Objective: Evaluate the sealing conditions of adhesive restorations after the chemomechanical removal of carious tissue with a papain gel (Papacarie®) and after the traditional method of caries removal utilizing rotatory instruments. Method: Seventeen human premolars with caries lesions envolving oclusal (enamel marginal) and cervical (dentin marginal) surfaces was used. The sample was divided in two groups: G1 removal of caries tissue with the traditional method G2 removal of caries tissue with the chemomechanical technique (Papacarie®). After the removal of caries tissue with one of the two techniques, the adhesive system Prime&Bond 2.1® was applied and the cavities were restored with composite resin (Filtek Z250®, A2). The test specimes were thermocycled (300 cycles at 5ºC – 55ºC, for 15 seconds in each temperature), isolated through the sealing of apices, immersed into basic fucsin during 24 hours, seccioned longitudinally through the restoration and assessed by three examiners that attributed marks according to the degree of dye penetration along the interface enamel/restoration and dentin/restoration in occlusal and cervical wall, respectively. Results: The statistical analysis using the Mann-Whitney test revealed the occurrence of marginal microleakage in both groups (Papacarie® and rotatory instruments) when the cervical surface was evaluated and there was no significant difference between them. Nevertheless, when the oclusal surface was evaluated there was a significant difference between the groups, because in Papacarie’s group had worst results. Conclusion: The sealing properties of composite resin restorations were harmed by the method of caries removal with Papacarie®