18 research outputs found

    Análise de lacunaridade de fenômenos agroambientais

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    Os fenômenos estudados em ciências agrárias e ambientais além da própria evolução são fortemente influenciados pela atividade humana e caracterizam-se pelo grande número de componentes interagindo de forma não linear em uma escala e produzindo as propriedades emergentes em outras escalas. Com essas características os fenômenos agroambientais considerados sistemas complexos e estudados utilizando vários conceitos desenvolvidos durante as últimas décadas entre os quais: fractais, multifractais, criticalidade auto-organizada e entropias. Neste trabalho analisou-se a dinâmica temporal das variáveis climáticas: precipitação, temperatura e vazão do rio e a distribuição espacial de focos de queimadas. Foi utilizado o método de lacunaridade, que serve para avaliar a distribuição de lacunas em um conjunto de dados. Utilizando os valores de lacunaridade para diferentes escalas temporais foi possível descrever o regime da chuva (fragmentação dos períodos chuvosos) e classificar dois padrões de precipitação no estado de Sergipe, um padrão formado pelas estações que se aproximam da costa sergipana e outro das estações que se localizam nas regiões do semiárido e agreste. A análise de lacunaridade mostrou-se útil para avaliação do impacto da atividade humana no regime natural da vazão do rio, no caso dos rios Atibaia e Jaguari a construção dos reservatórios do sistema Cantareira. Depois da construção dos reservatórios os valores da lacunaridade diminuíram em relação ao período antes da construção dos reservatórios indicando a diminuição de heterogeneidade da dinâmica da vazão devido à regulação do fluxo hídrico. Os resultados da análise de lacunaridade de séries temporais de temperatura e de precipitação do estado de Pernambuco demostraram que este método pode ser usado para identificar as regiões geográficas com comportamento temporal característico das variáveis climáticas. A análise de lacunaridade para dados bidimensionais foi aplicada na distribuição espacial de focos de queimadas detectadas na Amazônia legal durante o período 2000-2013. Nos anos com maior número de queimadas os valores de lacunaridade indicaram uma distribuição espacial mais homogênea comparando com períodos com menor número das queimadas. O método de lacunaridade (avaliando a heterogeneidade da distribuição espacial de queimadas) também mostrou se eficaz em identificação das estações seca e chuvosa. Estes resultados podem ser úteis em planejamento do uso de recursos hídricos, em planejamento das atividades agrícolas, desenvolvimento de estratégias para diminuir as consequências de fenômenos climáticos extremos (seca, cheia) e desastres naturais como incêndios florestais.The phenomena studied in agricultural and environmental sciences are characterized by their natural evolution and are also affected by human activity. They are comprised of a large number of components with non linear interactions on some scales, which produce emergent properties on other scales. These are characteristics of complex systems and can be studied using various concepts developed over the last decades such as fractals, multifractals, self-organized criticality and entropy. In this paper we analyzed the temporal dynamics of climate variables rainfall, temperature and stream flow, and spatial distribution of vegetation fires represented by hot pixels detected by satellites. We used the method of lacunarity that serves to describe the distribution of gaps in a data set. Using lacunarity values for different time scales it was possible to describe the rainfall regime (fragmentation of rainy periods) and classify two precipitation patterns in the state of Sergipe, one formed by stations approaching the Sergipe coast, and other formed by stations that are located in semiarid region. The lacunarity analysis was successful for evaluation of impact of human activity on natural regime of river flow, in the case of rivers Atibaia and Jaguari, caused by the construction of Cantareira system reservoirs. After the construction of the reservoirs lacunarity values of stream flow decreased, indicating a reduction of heterogeneity of flow dynamics due to regulation of water flow. The results of lacunarity analysis of time series of temperature and precipitation in the state of Pernambuco showed that this method can be used to identify the geographic regions with characteristic temporal behavior of climatic variables. The lacunarity analysis for two-dimensional data was applied to spatial distribution of hot pixels detected in Amazonia during the period 2000-2013. In the years with high number of hot pixels the lacunarity values were lower, indicating a more homogeneous spatial distribution compared with periods with low number of hot pixels. The lacunarity method has also shown to be effective in identifying the dry and rainy seasons, by capturing the heterogeneity of spatial distribution of hot pixels. These results may be useful in planning the use of water resources, planning of agricultural activities, developing strategies to reduce the impact of extreme weather events (drought, flood) and natural disasters such as forest fires.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPE

    Portal de Acesso às Informações das Ações das Universidades Federais em Resposta à Pandemia de Covid-19: uma análise do período pandêmico até a transição para uma pós-pandemia

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    During the pandemic, a new organization of the academic activities of the Federal Universities was necessary to undertake internal and external actions to face Covid-19. To share the actions carried out, the Ministry of Education (MEC) developed two information portals on the numbers of Covid-19 and the actions developed for basic and higher education. One of these portals is the "Coronavirus Panel – Monitoring the Federal Network" which brings together a set of information regarding the actions taken by educational institutions from the beginning of the pandemic to the current moment of transition to a post-pandemic. Using a method of analyzing quantitative and qualitative data, we seek to discuss and correlate data from Covid-19 cases and their peaks with actions involving teaching, prevention and support to the academic community. As a result, some panels of the portal and the analysis of data from the actions are presented in a correlated way, allowing the sharing of strategies and the historical understanding of which actions were used in facing the pandemic and in the transition from a post-pandemic.Durante a pandemia, foi necessária uma nova organização das atividades acadêmicas das Universidades Federais para empreender ações internas e externas de enfrentamento à Covid-19. Para compartilhar as ações realizadas, o Ministério da Educação (MEC) desenvolveu dois portais de informação sobre os números da Covid-19 e sobrea as ações desenvolvidas para a educação básica e superior. Um desses portais é o “Painel Coronavírus – Monitoramento da Rede Federal”, que reúne um conjunto de informações referente às ações realizadas pelas instituições de ensino desde o início da pandemia até o momento atual de transição para uma pós-pandemia. Utilizando um método de análise de dados quantitativos e qualitativos, buscou-se discorrer sobre os dados de casos de Covid-19 e seus picos como as ações envolvendo modalidade de ensino, prevenção e apoio à comunidade acadêmica. Como resultado, são apresentados de forma correlacionada alguns painéis do portal e a análise dos dados das ações, permitindo compartilhar as estratégias e a compreensão histórica de quais ações foram utilizadas no enfrentamento da pandemia e na transição de uma pós-pandemia

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Análise de condrocrânio de Rhizoprionodon porosus (Poey, 1861) da costa nordeste do Brasil

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    O gênero Rhizoprionodon (Whitley, 1929) compreende sete espécies distribuídas pelos oceanos Atlântico, Pacífico e Índico. No Brasil ocorrem duas espécies, o Rhizoprionodon porosus (Poey, 1861) e o lalandi (Valenciennes, 1839). O uso de técnicas morfométricas distintas da abordagem que utiliza proporções corporais, geralmente utilizadas em taxonomia, encontra limitações para esse grupo devido à falta nos elasmobrânquios de marcos anatômicos, propriamente ditos. Assim, no presente estudo será analisado o condrocrânio que é uma estrutura considerada espécie-especifica que apresenta forma angulosa, localizado na base do crânio que sustenta o encéfalo e serve para sua proteção. O estudo tem por objetivo verificar a hipótese sugerida na literatura de duas populações da espécie R. porosus na costa do Brasil (Lessa et al. 2011; Lessa, 2003). Uma delas corresponderia à costa setentrional do Nordeste (RN) e a outra à costa oriental desta região (PE). Para tanto, se realizou um estudo morfométrico comparativo do condrocrânio de R. porosus entre as regiões mencionadas utilizando-se para isso os métodos de análise multivariada. Em todas as análises verificou-se diferenças tanto para a fase adulta quanto para a fase juvenil em relação às regiões de captura. Na análise de discriminantes e no k-means obteve-se uma taxa de acerto de 100,0% na classificação dos condrocrânios. Não existe diferença do condrocrânio em relação ao sexo independente da região de captura. As variáveis que caracterizaram as diferenças entre as populações foram: a distância entre as fenestras rostral e baserostral, a distância entre a fenestra rostral e as cartilagens lateral rostral esquerda e direita e a distância entre a fossa pariental e a fontanela anterior, sendo que exemplares de R. porosus do RN apresentaram distâncias maiores. Verificou-se de fato diferença entre os condrocrânios de PE e RN nas fases adulta e juvenil. Esses resultados estão em conformidade com o padrão recentemente sugerido na literatura que indica duas populações na costa nordeste do Brasil.The genus Rhizoprionodon (Whitley, 1929) comprises seven species occurring in the Atlantic, Pacific and Indian Oceans; the species are small and medium-sized animals attaining about 150 cm, inhabiting coastal waters, estuaries and brackish waters and feeding mainly on mollusks, crustaceans and small fish. In Brazil the two species are found Rhizoprionodon porosus (Poey, 1861) and lalandi (Valenciennes, 1839). The use of morphometric approaches has limitations for this group due to lack of anatomical landmarks, since they have a continuous form without angles. This study will analyze the chondrocranium a structure that is considered species-specific, located at the base of the skull holding and protecting the brain, displaying a shape that exhibits numerous angles. The study aims to verify the hypothesis suggested in the literature of two populations of the species R. porosus off northeastern Brazil (Lessa et al. 2011; Lessa et al. 2008). One corresponds to the northern coast of the Northeast (RN) and the other to the eastern coast of this region (PE). For that we performed a comparative morphometric study of the chondrocranium of R. porosus between the indicated areas using multivariate analyses. Thus, there were differences both for adult and juvenile phases by regions of capture. The discriminant analysis and k-means yielded a hit rate of 100, 0%. In conclusion, there is indeed a difference between chondrocrania from Pernambuco and Rio Grande do Norte as showed by approaches used. These results are in accordance with the hypotheses recently suggested in the literature that indicates two populations on the coast of northeastern Brazil.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPE

    Activity pattern, budget and diurnal rhythmicity of the brown-throated three-toed sloth (Bradypus variegatus) in northeastern Brazil

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    Previous studies exploring the rhythmic activity of sloths of the Bradypus genus in undisturbed forests revealed cathemeral patterns of activity. In the current study we wished to examine sloth behavior in a highly disturbed secondary forest habitat. We evaluated activity pattern, time budget and rhythmic activities of brown-throated three-toed sloths (B. variegatus) living in the border of a highly disturbed forest fragment in northeastern Brazil. Three adults (2 females and 1 male) and 2 infants were studied over 29 days. Observational data were collected in 15 min increments over the 24-h day in the following categories: resting, moving, travelling, eating and grooming. Time series data were subjected to X2 periodogram, Fourier (Fast Fourier Transformation, FFT), cosinor and CircWave circadian rhythm analysis, and revealed significant 24-h rhythms in all behaviors in most circumstances. Unlike sloths located in an undisturbed forest, this population exhibited primarily diurnal activity patterns of behavior, with the center of gravity for each behavior occurring in the middle of the day. Furthermore, several behaviors were expressed in a bimodal pattern, with a morning and a late afternoon peak of activity. These data suggest that with decreased predator presence and with a more ubiquitous food source, sloths adjust their temporal niche to daytime. © 2020, Deutsche Gesellschaft für Säugetierkunde
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