8 research outputs found

    Estrutura e interação entre vegetação e ambiente de uma floresta ombrófila densa das terras baixas, Espírito Santo

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    O objetivo deste trabalho foi conhecer a estrutura e a composição de espécies da comunidade arbustiva-arbórea de um fragmento florestal de uma Floresta Ombrófila Densa das Terras Baixas, bem como verificar a interação da vegetação com as variáveis ambientais. Foram demarcadas 24 parcelas (20 x 20 m), totalizando 0,96 ha, onde foram medidos todos os indivíduos arbustivoarbóreos com diâmetro a altura do peito ≥ 2,5 cm. Além disso, foi calculada a porcentagem de abertura de dossel, por meio de fotografias hemisféricas, e realizada a caracterização química da camada superficial do solo (0 – 5 cm). Os dados foram correlacionados com a densidade absoluta de 25 espécies que possuíam no mínimo 30 indivíduos (obtidas a partir da análise fitossociológica), por meio da Análise de Correspondência Canônica. Foram registrados 4.585 indivíduos e identificadas 379 espécies distribuídas em 195 gêneros e 66 famílias botânicas. A densidade foi de 4.604 ind./ha e a área basal foi 31,88 m²/ha. O índice de Shannon (H’) encontrado para este estudo foi 5,41 e a equabilidade (J) foi 0,83, evidenciando a alta diversidade florística do fragmento e a sua semelhança com áreas bem preservadas da Mata Atlântica. A espécie de maior destaque em Valor de Importância (VI) foi Actinostemon klotzschii (Didr.) Pax, principalmente devido a densidade e frequência. Houve predominância de espécies secundárias tardias (51,9%) e de dispersão zoocórica (72,3%), evidenciando que o fragmento estudado está em bom estado de conservação. A partir da Análise de Correspondência Canônica foi possível comprovar que as variáveis fósforo, magnésio, matéria orgânica, nitrogênio, potássio e abertura de dossel exerceram influência sobre a distribuição das espécies deste fragmento (p<0,05), com destaque para a Xylopia frutescens Aubl. que apresentou elevada correspondência com a porcentagem de abertura de dossel e para as espécies Actinostemon klotzschii (Didr.) Pax, Chrysophyllum lucentifolium Cronquist, Ecclinusa ramiflora Mart., Eugenia platyphylla O.Berg e Rinorea bahiensis (Moric.) Kuntze que se desenvolveram em locais com menor necessidade de nutrientes. Com base no exposto, pode-se concluir que a vegetação possui alta riqueza de espécies e que as variáveis ambientais exercem influência sobre a distribuição das espécies deste fragmento indicando a possibilidade de implantação dessas espécies em locais com maior exposição a luminosidade e baixa fertilidade.The objective of this study was to determine the structure and species composition of shrub-tree community of a forest fragment in Lowlands Rain Forest and verify the interaction of vegetation with environmental variables. 24 plots (20 x 20 m) were marked, totaling 0.96 ha, in which were measured every shrub-trees individuals with diameter at breast height ≥ 2.5 cm. In addition, was calculated the percentage of canopy openness through hemispherical photographs and were performed the chemical characterization of the surface soil layer (0-5 cm). The data were correlated with the absolute density of 25 species that had at least 30 individuals (obtained from the phytosociological analysis) through Canonical Correspondence Analysis. 4,585 individuals were recorded and 379 species were identified, distributed in 195 genera and 66 botanical families. The density was 4,604 ind./ha and basal area was 31.88 m²/ha. The Shannon index (H') found in this study was 5.41 and evenness (J) was 0.83, suggesting the high floristic diversity of the fragment and its similarity with preserved areas of Atlantic Forest. The most remarkable species in Importance Value (IV) was Actinostemon klotzschii (Didr.) Pax, mainly due to density and frequency. Were predominant Late Secondary species (51,9%) and zoochoric dispersion (72.3%), indicating that the studied fragment is in good condition. From the Canonical Correspondence Analysis was possible to prove that the variables phosphorus, magnesium, organic matter, nitrogen, potassium and canopy openness influenced the distribution of species on this fragment (p <0.05), especially for Xylopia frutescens Aubl. that showed high correspondence with the percentage of canopy openness and the Actinostemon klotzschii (Didr.) Pax, Chrysophyllum lucentifolium Cronquist, Ecclinusa ramiflora Mart., Eugenia platyphylla O.Berg and Rinorea bahiensis (Moric.) Kuntze that developed in places with less nutrients. Based on the foregoing, it can be concluded that the vegetation has high species richness and the environmental variables influence on the distribution of species of this fragment indicating the possibility of implantation of these species in places with higher exposure to light and low fertility.CAPE

    Estrutura e sucessão ecológica de uma comunidade florestal urbana no sul do Espírito Santo

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    Comunidades florestais são ambientes dinâmicos, nas quais processos de sucessão ocorrem naturalmente, podendo conduzir à maturidade da floresta. O objetivo deste estudo foi avaliar a estrutura do componente arbustivo-arbóreo de um fragmento de Floresta Estacional Semidecidual e caracterizar o seu estágio sucessional. O estudo foi realizado no município de Alegre, Espírito Santo, na ARIE Laerth Paiva Gama. A amostragem de todos os indivíduos com DAP ≥ 5 cm foi realizada por meio de pontos-quadrantes. Além dos parâmetros ecológicos foi obtida a estrutura diamétrica para a comunidade. As espécies foram classificadas quanto ao grupo ecológico em pioneiras, secundárias iniciais e secundárias tardias, e quanto ao grau de ameaça de extinção. Foram registradas 112 espécies, 81 gêneros e 34 famílias, das quais se destacaram em Valor de Importância Pseudopiptadenia contorta (15,33), Apuleia leiocarpa (5,08), Acosmium lentiscifolium (4,42) e Parapiptadenia pterosperma (4,30). O índice de Shannon foi de 4,17 e a equabilidade de 0,87, sendo considerados valores elevados para florestas estacionais semideciduais. Com relação à avaliação dos grupamentos ecológicos, as secundárias tardias e iniciais se destacaram em riqueza, no entanto as iniciais foram mais abundantes na comunidade. Deste modo, o remanescente florestal estudado pode ser caracterizado como pertencente ao estágio sucessional inicial-intermediário.Forest communities are dynamic environments in which succession processes occur naturally, may lead to the maturity of the forest. The objective of this study was to evaluate the structure of the woody component of a fragment of semideciduous forest and characterize their successional stage. The study was conducted in the municipality of Alegre, Espirito Santo, in ARIE Laerth Paiva Gama. The sampling of all individuals with DBH ≥ 5 cm was performed by points quadrants. In addition to the ecological parameters it was obtained diameter structure to the community. The species were classified according to environmental group in pioneers, early secondary and late secondary, and the degree of threat of extinction. Were recorded the 112 species, 81 genera and 34 families, of which have excelled in importance value were Pseudopiptadenia contorta (15.33), Apuleia leiocarpa (5.08), Acosmium lentiscifolium (4.42) and Parapiptadenia pterosperma (4.30). The Shannon index was 4.17 and the evenness of 0.87 and are considered high values ​​for semideciduous forests. As to the evaluation of ecological groups, late and early secondary stood out in wealth, however initials were more abundant in the community. Thus, the remaining forest studied can be characterized as belonging to the initial-intermediate stage succession

    Estrutura e sucessão ecológica de uma comunidade florestal urbana no sul do Espírito Santo

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    Resumo Comunidades florestais são ambientes dinâmicos, nas quais processos de sucessão ocorrem naturalmente, podendo conduzir à maturidade da floresta. O objetivo deste estudo foi avaliar a estrutura do componente arbustivo-arbóreo de um fragmento de Floresta Estacional Semidecidual e caracterizar o seu estágio sucessional. O estudo foi realizado no município de Alegre, Espírito Santo, na ARIE Laerth Paiva Gama. A amostragem de todos os indivíduos com DAP ≥ 5 cm foi realizada por meio de pontos-quadrantes. Além dos parâmetros ecológicos foi obtida a estrutura diamétrica para a comunidade. As espécies foram classificadas quanto ao grupo ecológico em pioneiras, secundárias iniciais e secundárias tardias, e quanto ao grau de ameaça de extinção. Foram registradas 112 espécies, 81 gêneros e 34 famílias, das quais se destacaram em Valor de Importância Pseudopiptadenia contorta (15,33), Apuleia leiocarpa (5,08), Acosmium lentiscifolium (4,42) e Parapiptadenia pterosperma (4,30). O índice de Shannon foi de 4,17 e a equabilidade de 0,87, sendo considerados valores elevados para florestas estacionais semideciduais. Com relação à avaliação dos grupamentos ecológicos, as secundárias tardias e iniciais se destacaram em riqueza, no entanto as iniciais foram mais abundantes na comunidade. Deste modo, o remanescente florestal estudado pode ser caracterizado como pertencente ao estágio sucessional inicial-intermediário

    Seasonal litterfall and nutrients in an Atlantic Forest fragmente

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    Litter dynamics is one of the fundamental processes for the growth and maintenance of native forest fragments, being considered the main pathway for nutrient cycling in forests. Studies on litter production and nutrient content therefore provide insights that provide a better understanding of nutrient dynamics. This study identifies the seasonality and meteorological conditions that influence the quantity and return of nutrients through litter in an Atlantic Forest fragment. Litter sampling was carried out monthly in 12 permanent plots. Each plot contained 5 littertraps distributed systematically. The litter was classified, and the dry mass and nutrients in the leaves and branches and miscellaneous fractions was quantified. Seasonal behavior was observed, with the highest depositions in the winter season. The average annual production was 6.78 Mg ha-1, with 64.9% being composed of leaves. The mean annual nutrient intake was 135.1, 115.7, 39.7, 23.5, 17.6 and 4.6 kg ha-1 for Ca, N, K, Mg, S and P, respectively. The meteorological variable precipitation influenced the deposition pattern. The increase in nutrient-use efficiency in the second year compared to the first indicates that plants strategically may be re-translocating relative amounts of their nutrients under water stress conditions

    Socioeconomia dos pescadores do Macrobrachium amazonicum em Breves, arquipélago do Marajó, Brasil1

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    O objetivo do presente estudo foi avaliar a condição socioeconômica dos(as) pescadores(as) do camarão-da-Amazônia (Macrobrachium amazonicum) no município de Breves, arquipélago do Marajó (Pará – Brasil). O estudo foi realizado no período de janeiro a junho de 2019, sendo utilizado um questionário para dezoito pescadores(as). Quanto à distribuição por gênero, observa-se a presença das mulheres na pesca com 61,0% de representação. Elas apresentam faixa etária entre 31 a 40 anos (28,0%), sendo que mais da metade (33,0%) tem de 4 a 5 filhos. Quanto à escolaridade, o município de Breves possui 22,0% dos pescadores iletrados e 52,0% que têm ensino fundamental incompleto, o que corresponde à maior parte dos entrevistados. Constatou-se que os pescadores do camarão-da-Amazônia necessitam de políticas públicas para promoção de ações educacionais e pesqueiras, geração de emprego e renda, com melhoria da qualidade de vida.

    GIS-Based Approach Applied to Study of Seasonal Rainfall Influence over Flood Vulnerability

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    Flooding occurrence is one of the most common phenomena that impact urban areas, and this intensifies during heavy rainfall periods. Knowing the areas with the greatest vulnerability is of paramount importance as it allows mitigating actions to be implemented in order to minimize the generated impacts. In this context, this study aimed to use Geographic Information System (GIS) tools to identify the areas with greater flooding vulnerability in Espírito Santo state, Brazil. The study was based on the following methodological steps: (1) a Digital Elevation Model (DEM) acquisition and watersheds delimitation; (2) maximum and accumulated rainfall intensity calculations for the three studied periods using meteorological data; (3) a land use and occupation map reclassification regarding flood vulnerability and fuzzy logic application; (4) an application of Euclidean distance and fuzzy logic in hydrography and water mass vector variables; (5) a flood vulnerability model generation. Based on the found results, it was observed that the metropolitan and coastal regions presented as greater flood vulnerability areas during the dry season, as in these regions, almost all of the 9.18% of the state’s area was classified as highly vulnerable, while during rainy season, the most vulnerable areas were concentrated in Caparaó and in the coastal and immigration and metropolitan regions, as in these regions, almost all of the 12.72% of the state’s area was classified as highly vulnerable. In general, by annually distributing the rainfall rates, a greater flood vulnerability was observed in the metropolitan and coastal and immigration regions, as in these areas, almost all of the 7.72% of the state’s area was classified as highly vulnerable. According to the study, Espírito Santo state was mostly classified as a low (29.15%) and medium (28.06%) flood vulnerability area considering the annual period, while its metropolitan region has a very high flood vulnerability risk. Finally, GIS modeling is important to assist in decision making regarding public management and the employed methodology presents worldwide application potential

    GIS-Based Approach Applied to Study of Seasonal Rainfall Influence over Flood Vulnerability

    No full text
    Flooding occurrence is one of the most common phenomena that impact urban areas, and this intensifies during heavy rainfall periods. Knowing the areas with the greatest vulnerability is of paramount importance as it allows mitigating actions to be implemented in order to minimize the generated impacts. In this context, this study aimed to use Geographic Information System (GIS) tools to identify the areas with greater flooding vulnerability in Esp&iacute;rito Santo state, Brazil. The study was based on the following methodological steps: (1) a Digital Elevation Model (DEM) acquisition and watersheds delimitation; (2) maximum and accumulated rainfall intensity calculations for the three studied periods using meteorological data; (3) a land use and occupation map reclassification regarding flood vulnerability and fuzzy logic application; (4) an application of Euclidean distance and fuzzy logic in hydrography and water mass vector variables; (5) a flood vulnerability model generation. Based on the found results, it was observed that the metropolitan and coastal regions presented as greater flood vulnerability areas during the dry season, as in these regions, almost all of the 9.18% of the state&rsquo;s area was classified as highly vulnerable, while during rainy season, the most vulnerable areas were concentrated in Capara&oacute; and in the coastal and immigration and metropolitan regions, as in these regions, almost all of the 12.72% of the state&rsquo;s area was classified as highly vulnerable. In general, by annually distributing the rainfall rates, a greater flood vulnerability was observed in the metropolitan and coastal and immigration regions, as in these areas, almost all of the 7.72% of the state&rsquo;s area was classified as highly vulnerable. According to the study, Esp&iacute;rito Santo state was mostly classified as a low (29.15%) and medium (28.06%) flood vulnerability area considering the annual period, while its metropolitan region has a very high flood vulnerability risk. Finally, GIS modeling is important to assist in decision making regarding public management and the employed methodology presents worldwide application potential

    Safety and efficacy of eculizumab in anti-acetylcholine receptor antibody-positive refractory generalised myasthenia gravis (REGAIN): a phase 3, randomised, double-blind, placebo-controlled, multicentre study

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    Background Complement is likely to have a role in refractory generalised myasthenia gravis, but no approved therapies specifically target this system. Results from a phase 2 study suggested that eculizumab, a terminal complement inhibitor, produced clinically meaningful improvements in patients with anti-acetylcholine receptor antibody-positive refractory generalised myasthenia gravis. We further assessed the efficacy and safety of eculizumab in this patient population in a phase 3 trial. Methods We did a phase 3, randomised, double-blind, placebo-controlled, multicentre study (REGAIN) in 76 hospitals and specialised clinics in 17 countries across North America, Latin America, Europe, and Asia. Eligible patients were aged at least 18 years, with a Myasthenia Gravis-Activities of Daily Living (MG-ADL) score of 6 or more, Myasthenia Gravis Foundation of America (MGFA) class II\ue2\u80\u93IV disease, vaccination against Neisseria meningitides, and previous treatment with at least two immunosuppressive therapies or one immunosuppressive therapy and chronic intravenous immunoglobulin or plasma exchange for 12 months without symptom control. Patients with a history of thymoma or thymic neoplasms, thymectomy within 12 months before screening, or use of intravenous immunoglobulin or plasma exchange within 4 weeks before randomisation, or rituximab within 6 months before screening, were excluded. We randomly assigned participants (1:1) to either intravenous eculizumab or intravenous matched placebo for 26 weeks. Dosing for eculizumab was 900 mg on day 1 and at weeks 1, 2, and 3; 1200 mg at week 4; and 1200 mg given every second week thereafter as maintenance dosing. Randomisation was done centrally with an interactive voice or web-response system with patients stratified to one of four groups based on MGFA disease classification. Where possible, patients were maintained on existing myasthenia gravis therapies and rescue medication was allowed at the study physician's discretion. Patients, investigators, staff, and outcome assessors were masked to treatment assignment. The primary efficacy endpoint was the change from baseline to week 26 in MG-ADL total score measured by worst-rank ANCOVA. The efficacy population set was defined as all patients randomly assigned to treatment groups who received at least one dose of study drug, had a valid baseline MG-ADL assessment, and at least one post-baseline MG-ADL assessment. The safety analyses included all randomly assigned patients who received eculizumab or placebo. This trial is registered with ClinicalTrials.gov, number NCT01997229. Findings Between April 30, 2014, and Feb 19, 2016, we randomly assigned and treated 125 patients, 62 with eculizumab and 63 with placebo. The primary analysis showed no significant difference between eculizumab and placebo (least-squares mean rank 56\uc2\ub76 [SEM 4\uc2\ub75] vs 68\uc2\ub73 [4\uc2\ub75]; rank-based treatment difference \ue2\u88\u9211\uc2\ub77, 95% CI \ue2\u88\u9224\uc2\ub73 to 0\uc2\ub796; p=0\uc2\ub70698). No deaths or cases of meningococcal infection occurred during the study. The most common adverse events in both groups were headache and upper respiratory tract infection (ten [16%] for both events in the eculizumab group and 12 [19%] for both in the placebo group). Myasthenia gravis exacerbations were reported by six (10%) patients in the eculizumab group and 15 (24%) in the placebo group. Six (10%) patients in the eculizumab group and 12 (19%) in the placebo group required rescue therapy. Interpretation The change in the MG-ADL score was not statistically significant between eculizumab and placebo, as measured by the worst-rank analysis. Eculizumab was well tolerated. The use of a worst-rank analytical approach proved to be an important limitation of this study since the secondary and sensitivity analyses results were inconsistent with the primary endpoint result; further research into the role of complement is needed. Funding Alexion Pharmaceuticals
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