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1.
Integr Environ Assess Manag ; 16(5): 643-654, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32633889

RESUMO

Fundão dam (Minas Gerais, Brazil) breached on 5 November 2015, releasing 50 million m³ of Fe ore tailings and dam materials into the upper Doce River system. The tailings travelled 670 km along the river system to the ocean. Starting on 17 November 2015, 6 days before the tailings reached the Doce River mouth, a water quality monitoring program with a daily sampling schedule was implemented by Samarco Mineração S.A. (Samarco) to assess the impacts on marine water and sediment quality. Between November 2015 and August 2017 water and sediment quality were monitored at 28 locations offshore from the Doce River mouth. The sampling areas were grouped by hydrological and metocean season (i.e., rainy and dry seasons and wave and wind climates), distance from the river mouth (<5 km, >5 km and within a Marine Protected Area), and water depth. The data were compared to the Brazilian water quality standards and prebreach conditions. Statistical tests were conducted to evaluate temporal and spatial trends and patterns. For the water quality parameters of relevance (total suspended solids, turbidity, total and dissolved Fe, Al, and Mn), pulses of concentration increases were observed right after the arrival of the plume in the coastal zone and during the subsequent rainy seasons. Exceedances of prebreach conditions were more frequent closer to the Doce River mouth. During the dry season, concentrations tended to decrease, reaching prebreach levels for a number of parameters, with small short-term pulses associated with metocean factors. For sediment quality parameters of relevance (particle size, Fe, Al, and Mn), Fe was the only one that clearly resulted from the dam breach, which was mediated by river influence and oceanographic factors affecting particle size distribution. Results indicated that the Fundão dam failure did affect water and sediment quality in the Atlantic Ocean, with greater impacts closer to the river mouth and immediately after the arrival of the tailings plume, with concentrations gradually returning to preevent levels over time. Integr Environ Assess Manag 2020;16:643-654. © 2020 SETAC.

2.
Integr Environ Assess Manag ; 16(5): 583-595, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32648998

RESUMO

The Fundão dam (Minas Gerais, Brazil) breach resulted in the transport and deposition of Fe mine tailings and debris for approximately 670 km along the Doce River watershed. Following the event, an extensive water quality monitoring program was implemented. The results generated by this program were used to assess the temporal and spatial impacts of the event on water quality. Data from several sampling sites situated along affected watercourses collected from 6 November 2015 to 27 September 2017 were evaluated. The sampling area was grouped into 4 zones delineated by hydropower plant dams located along the Doce River watershed and divided into 5 distinct time periods related to hydrological seasonality. Data were also compared to the Brazilian standards of water quality and available pre-event conditions. Principal component analysis followed by analysis of variance (ANOVA) tests were performed to evaluate the observed temporal and spatial trends and patterns. The results indicated that concentrations of 58 water quality parameters increased with the arrival of the tailings wave released by the breach, generally exceeding pre-event and regulatory levels. Persistent or seasonally recurring concentrations were observed for 30 water quality parameters. Concentrations of total and dissolved forms of Fe, Al, Mn, total P, total suspended solids, and turbidity tended to increase during the wet season and decrease during the dry season, this trend being more pronounced close to the dam. The water quality changes were more pronounced immediately after the arrival of the tailings wave, gradually decreasing over time and returning prebreach conditions, but fluctuated seasonally in response to the natural variation in river flow. Integr Environ Assess Manag 2020;16:583-595. © 2020 SETAC.

3.
J Sci Food Agric ; 100(7): 3099-3110, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32083322

RESUMO

BACKGROUND: The in vitro gas production (GP) technique has been useful for evaluating the potential degradability of feedstuffs in ruminal environments; GP is related to the components of feedstuff ingredients. RESULTS: Linear models were generated and validated as alternatives of quantifying neutral detergent-soluble fiber, starch (St)/hemicellulose (Hem) and cellulose (Cel) through GP. Residuals of models obtained from the peaks of GP [0-8 h (GP-8), > 8-24 h (GP-24), > 24-48 h (GP-48) and > 24-81 h (GP-81)] of 0.02, 0.04, 0.08, 0.12 and 0.20 g of glucose (Glu), St and Cel respectively. The incubations were analyzed in mixtures of Glu, St and Cel. The best fitting models (r2 from 0.709 to 0.935) were tested on corn stover (CS) to quantify rapid fermentation fractions (RF; equivalent to Glu), medium fermentation fractions (MF; equivalent to St) and low fermentation fractions (LF48; equivalent to Cel); in CS, RF, MF and LF models had standardized residuals < 0.09. The analysis with Leucaena (Leucaena leucocephala Lam. de Wit) and star grass (Cynodon nlemfuensis Vanderyst) consider high-protein ingredients. CONCLUSION: The in vitro GP of RF, MF and LF48 fractions equivalent to Glu, St and Cel are affected by maturity and harvest time even when the chemical composition remains similar, and so RF, MF and LF48 should be considered during the design of ruminant diets. In vitro GP could be used to quantify the components of some forages, although further studies are necessary. © 2020 Society of Chemical Industry.

4.
Rev. Col. Méd. Cir. Guatem ; 156(2): 61-66, nov. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-986624

RESUMO

Propósito: desarrollar un modelo estadístico predictivo de la prevalencia de desnutrición crónica infantil a nivel a nivel departamental en Guatemala. Material y método: se realizó un estudio ecológico, partiendo de 142 variables agrupadas en categorías relacionadas con las dimensiones demográfica, social, económica, política, de salud y de servicios de salud, utilizando la prevalencia de desnutrición crónica infantil como la variable dependiente. Los datos provienen de las bases de datos oficiales de 2014. Posteriormente se utilizó un modelo de regresión lineal múltiple para identificar las variables que mejor explican la desnutrición crónica infantil. Resultados: finalmente el modelo se construyó con 9 variables de alta significancia estadística y se obtuvo un R2 de 88% con un resultado significativo (p<0.001). Las variables asociadas con la desnutrición crónica infantil fueron: la pobreza, el ingreso familiar, la educación de la madre, la presencia de informalidad en el empleo, la presencia de diabetes en el hogar, la falta de acceso al agua potable y las bajas inversiones locales en la salud, el bajo per cápita en salud y la falta de acceso a servicios públicos. (AU)


Assuntos
Humanos , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Pobreza/estatística & dados numéricos , Zona Rural , Modelos Estatísticos , Desnutrição/etiologia , Diabetes Mellitus/economia , Emprego/economia , Nutrição Materna/educação , Estudos Ecológicos , Guatemala/epidemiologia
5.
An. acad. bras. ciênc ; 89(3): 1579-1589, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886727

RESUMO

ABSTRACT Studies on belowground roots biomass have increasingly reported the importance of the contribution of this compartment in carbon stock maintenance in mangrove forests. To date, there are no estimates of this contribution in Brazilian mangrove forests, although the country has the second largest area of mangroves worldwide. For this study, trenches dug in fringing forests in Guaratiba State Biological Reserve (Rio de Janeiro, Brazil) were used to evaluate the contribution of the different classes of roots and the vertical stratification of carbon stock. The total carbon stock average in belowground roots biomass in these forests was 104.41 ± 20.73 tC.ha−1. From that, an average of 84.13 ± 21.34 tC.ha−1 corresponded to the carbon stock only in fine roots, which have diameters smaller than 5 mm and are responsible for over 80% of the total belowground biomass. Most of the belowground carbon stock is concentrated in the first 40 cm below the surface (about 70%). The root:shoot ratio in this study is 1.14. These estimates demonstrate that the belowground roots biomass significantly contributes, more than 50%, to the carbon stock in mangrove forests. And the mangrove root biomass can be greater than that of other Brazilian ecosystems.


Assuntos
Solo/química , Carbono/análise , Áreas Alagadas , Brasil , Biomassa
6.
An Acad Bras Cienc ; 89(3): 1579-1589, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28813100

RESUMO

Studies on belowground roots biomass have increasingly reported the importance of the contribution of this compartment in carbon stock maintenance in mangrove forests. To date, there are no estimates of this contribution in Brazilian mangrove forests, although the country has the second largest area of mangroves worldwide. For this study, trenches dug in fringing forests in Guaratiba State Biological Reserve (Rio de Janeiro, Brazil) were used to evaluate the contribution of the different classes of roots and the vertical stratification of carbon stock. The total carbon stock average in belowground roots biomass in these forests was 104.41 ± 20.73 tC.ha-1. From that, an average of 84.13 ± 21.34 tC.ha-1 corresponded to the carbon stock only in fine roots, which have diameters smaller than 5 mm and are responsible for over 80% of the total belowground biomass. Most of the belowground carbon stock is concentrated in the first 40 cm below the surface (about 70%). The root:shoot ratio in this study is 1.14. These estimates demonstrate that the belowground roots biomass significantly contributes, more than 50%, to the carbon stock in mangrove forests. And the mangrove root biomass can be greater than that of other Brazilian ecosystems.


Assuntos
Carbono/análise , Solo/química , Áreas Alagadas , Biomassa , Brasil
7.
An Acad Bras Cienc ; 89(2): 973-989, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28640348

RESUMO

In order to contribute to understand the factors that control the provisioning of the ecosystem service of carbon storage by mangroves, data on carbon stock and sequestration in the aboveground biomass (AGB) from 73 articles were averaged and tested for the dependence on latitude, climatic parameters, physiographic types and age. Global means of carbon stock (78.0 ± 64.5 tC.ha-1) and sequestration (2.9 ± 2.2 tC.ha-1.yr-1) showed that mangroves are among the forest ecosystems with greater capacity of carbon storage in AGB per area. On the global scale, carbon stock increases toward the equator (R²=0.22) and is dependent on 13 climatic parameters, which can be integrated in the following predictive equation: Carbon Stock in AGB = -16.342 + (8.341 x Isothermality) + (0.021 x Annual Precipitation) [R²=0.34; p < 0.05]. It was shown that almost 70% of carbon stock variability is explained by age. Carbon stock and sequestration also vary according to physiographic types, indicating the importance of hydroperiod and edaphic parameters to the local variability of carbon stock. By demonstrating the contribution of local and regional-global factors to carbon stock, this study provides information to the forecast of the effects of future climate changes and local anthropogenic forcings on this ecosystem service.


Assuntos
Sequestro de Carbono , Carbono/análise , Carbono/química , Áreas Alagadas , Análise de Variância , Biomassa , Valores de Referência , Análise de Regressão , Clima Tropical
8.
An. acad. bras. ciênc ; 89(2): 973-989, Apr.-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886715

RESUMO

ABSTRACT In order to contribute to understand the factors that control the provisioning of the ecosystem service of carbon storage by mangroves, data on carbon stock and sequestration in the aboveground biomass (AGB) from 73 articles were averaged and tested for the dependence on latitude, climatic parameters, physiographic types and age. Global means of carbon stock (78.0 ± 64.5 tC.ha-1) and sequestration (2.9 ± 2.2 tC.ha-1.yr-1) showed that mangroves are among the forest ecosystems with greater capacity of carbon storage in AGB per area. On the global scale, carbon stock increases toward the equator (R²=0.22) and is dependent on 13 climatic parameters, which can be integrated in the following predictive equation: Carbon Stock in AGB = -16.342 + (8.341 x Isothermality) + (0.021 x Annual Precipitation) [R²=0.34; p < 0.05]. It was shown that almost 70% of carbon stock variability is explained by age. Carbon stock and sequestration also vary according to physiographic types, indicating the importance of hydroperiod and edaphic parameters to the local variability of carbon stock. By demonstrating the contribution of local and regional-global factors to carbon stock, this study provides information to the forecast of the effects of future climate changes and local anthropogenic forcings on this ecosystem service.


Assuntos
Carbono/análise , Carbono/química , Áreas Alagadas , Sequestro de Carbono , Valores de Referência , Clima Tropical , Análise de Regressão , Análise de Variância , Biomassa
9.
An Acad Bras Cienc ; 88 Suppl 1: 517-25, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27142552

RESUMO

The formation of annual growth rings has been confirmed for several mangrove species in the last decade, among which is the Rhizophora mangle. However, the record of annual rings for this species was made in a region with high hydric seasonality, a widely recognized induction factor of annual rings in tropical species. In this sense, the present study aimed to verify the occurrence of annual growth rings in R. mangle in the mangroves of Guaratiba (Rio de Janeiro, Southeastern Brazil), a region with low hydric seasonality. For this purpose, the crossdating technique was applied in ten trees collected with known age (seven years). The growth rings are characterized by alternating layers of low vessel density (earlywood) and high vessel density (latewood). Multiple regression analysis indicated that growth rings width variation is driven by precipitation, water surplus, water deficit and water storage. Crossdating analysis confirmed the existence of annual growth rings in the R. mangle in Guaratiba. This discovery in a region with low hydric seasonality increases the dendrocronological potential of this species and suggests the importance of biological factors (eg. phenological behavior) as complementary inductors for the formation of growth rings in this species.


Assuntos
Clima , Rhizophoraceae/crescimento & desenvolvimento , Brasil , Fatores de Tempo , Árvores/crescimento & desenvolvimento
10.
Artrosc. (B. Aires) ; 22(1): 1-11, mar. 2015.
Artigo em Espanhol | LILACS, BINACIS | ID: lil-767467

RESUMO

Se realizó una revisión bibliográfica sobre el estado actual de las ligamentoplastias del LCA, incluyendo bases anatómicas, funcionales y tratamiento quirúrgico, así como un estudio retrospectivo de las ligamentoplastias del LCA mediante técnica SAC con más de 10 años de evolución. En dicho estudio se valoran parámetros clínicos y radiológicos mediante escalas clínicas y TAC, estableciendo relaciones entre la posición y ensanchamiento de los túneles con los resultados clínicos a largo plazo.


We performed a literature review on the current status of the ACL repair, including anatomical basis, functional and surgical treatment, as well as a retrospective study of the ACL repair by SAC technique with over 10 years of evolution. This study evaluated clinical and radiological parameters, clinical scales and TAC by establishing relationships between the position and broadening of the tunnels with long-term clinical results.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Ligamento Cruzado Anterior/lesões , Procedimentos Cirúrgicos Minimamente Invasivos , Reconstrução do Ligamento Cruzado Anterior , Traumatismos do Joelho/cirurgia , Seguimentos , Imagem por Ressonância Magnética , Resultado do Tratamento , Tomografia Computadorizada por Raios X
11.
Acta Ortop Mex ; 23(3): 153-7, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19739350

RESUMO

The calcaneal tendon lesion is very important due to the role of this tendon on gait performance, therefore a treatment strategy allowing the patient to resume activities of daily living as soon as possible is of the utmost importance. Treatment with a surgical approach involving the lateral peroneus brevis tendon facilitates bipodal support and immediate rehabilitation allowing the patient to resume activities of daily living as soon as possible.


Assuntos
Tendão do Calcâneo/lesões , Tendão do Calcâneo/cirurgia , Tendões/transplante , Adulto , Doença Crônica , Humanos , Masculino , Procedimentos Ortopédicos/métodos
12.
Ginecol. obstet. Méx ; 62(9): 285-7, sept. 1994.
Artigo em Espanhol | LILACS | ID: lil-198937

RESUMO

Se estudiaron 208 pacientes en puerperio inmediato, seleccionadas en forma aleatoria, a quienes se les practicó oclusión tubaria bilateral voluntaria por la técnica de Pomeroy modificada con abordaje abdominal infraumbilical con anestesia local. El procedimiento se consideró seguro y eficaz. Su aplicación reduce el costo hospitalario y el riesgo operatorio


Assuntos
Anestesia Local , Esterilização Tubária/métodos , Estradiol , Laparotomia , Óvulo/fisiologia , Ultrassom
14.
Ginecol. obstet. Méx ; 56: 87-90, abr. 1988. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-60879

RESUMO

Se realizaron 5,000 citologías exfoliativas cervicovaginales y su correlación con los cambios histológicos en la infeccicón por virus del papiloma humano. Se sugiere que la infección cervical por virus del papiloma humano es un factor importante en el origen de la neoplasia intraepitelial cervical


Assuntos
Humanos , Feminino , Colo do Útero/patologia , Infecções Tumorais por Vírus/patologia , Neoplasias do Colo do Útero/patologia , Infecção Focal/diagnóstico , Papillomaviridae/isolamento & purificação
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