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1.
Sci. agric ; 79(4): e20200319, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1290206

RESUMO

Alternatives to enhance the consensual low phosphorus (P) use efficiency of agriculture may include use of phosphate rock (PR) and plant species with unequal ability to get soil and rock P interplanted in cropping systems to allow plants with higher ability to facilitate access to P of plants with lower ability. This study investigated (i) the maize and three soil cover crops on their capacity to acquire P from PR and (ii) measured P acquisition of maize interplanted with the soil cover crop with the highest capacity to acquire P shown in (i). Experiments were carried out in a greenhouse, with plants grown in single and mixed cropping in pots containing a sandy, low-P soil amended with Monocalcium Phosphate (McP) or the Brazilian PR Itafós. Plant biomass production with PR, in relation to McP, was 83.7 % for buckwheat, 83.6 % for forage radish, 51.8 % for maize, and 0.3 % for pigeon pea. Buckwheat showed capacity of acquiring P from PR; nevertheless, it did not increase growth or P nutrition of maize interplanted in the soil amended with PR, showing no significant P facilitation. The soil amended with McP showed competition between the two plants in the pots. Maize had a greater growth in mixed than in single cropping and this occurred at the expenses of buckwheat. Despite the P mobilization potential of buckwheat, its simple interplanting with maize did not produce positive results.


Assuntos
Fosfatos , Fósforo , Fagopyrum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Zonas Agrícolas/análise
2.
Data Brief ; 34: 106636, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33364271

RESUMO

Integrity of most of tropical wetlands is threatened because they are often considered freely available resources of land and water. The Araguaia River Basin is one of the Brazilian basins most influenced by tropical seasonal floods, in addition to being rich in biodiversity and providing diverse ecosystem services. Here, we propose the analysis of the landscape of Araguaia Basin in terms of terrain units, rainfall, land use/cover and gross primary productivity (GPP). For this, the integration of different databases was made, including the topographic domains, protected areas and indigenous lands; land use/cover map (year 2016); time series of GPP derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor (period of 2000-2015); Shuttle Radar Topography Mission (SRTM) digital elevation models (DEM); and precipitation data produced by the WorldClim version 2 dataset. GPP time serie were processed using statistical methods of decomposition throughout R software. The proposed methodology can assist in new studies aimed at land use changes and carbon cycles.

3.
PLoS One ; 14(3): e0212876, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30893330

RESUMO

We performed phylogeographic and genetic structure analyses of Neothraupis fasciata joined with species distribution modelling to evaluate whether: (1) the distribution of genetic variability shows a pattern expected by the isolation-by-distance model; (2) the influence of the Pleistocene climate changes on species distribution; and (3) climate/climatic stability (hypothesis of climatic stability) as a predictor of population genetic diversity. Based on two molecular datasets (ND2 and FIB-5), the isolation-by-distance hypothesis was not supported. The mitochondrial haplotype network indicated the existence of historically isolated populations at the southern range of the species distribution, and recent population expansion was identified by both neutrality tests and extended Bayesian skyline plot analysis. Thus, the climatic changes during the Pleistocene might have promoted the reconnection of the partially isolated southern populations, which may have persisted in the plateaus during the cycles of savanna contractions. Subsequently, this species (re)colonized northern areas of the species present distribution, following the continuous vegetation on the São Francisco and Central plateaus about 60 kyr, and also reached the Amazonian savannas likely via the central corridor. Thus, our results indicated that the intrinsic relationship between the relief heterogeneity (plateaus and depressions) and the climatic fluctuations, mainly in the Pleistocene, promoted population reconnection and demographic expansion of N. fasciata.


Assuntos
Distribuição Animal , Biodiversidade , Mudança Climática , Modelos Biológicos , Passeriformes/fisiologia , Animais , Teorema de Bayes , Brasil , DNA Mitocondrial/genética , Conjuntos de Dados como Assunto , Genética Populacional , Pradaria , Filogenia , Filogeografia
4.
J Environ Manage ; 232: 818-828, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30529869

RESUMO

The Brazilian Cerrado is the second largest biome in Latin America, extending over more than 200 million ha and hosts some of the most intensive agricultural activities for grain and beef production in the world. Because of the biodiversity richness and high levels of endemism, Cerrado is considered one of world's hotspot for biodiversity conservation. The objectives of this study are three-fold: to present a comprehensive division of Cerrado into different ecoregions that reflect the environmental heterogeneity within the biome; to analyze the ecoregions in terms of biophysical characteristics, protected areas, environmental liability in riparian permanent protection areas along watercourses, and priorities for biodiversity conservation; and to rank the ecoregions in terms of endangerment for biodiversity conservation and restoration. A previous study that delineated 22 ecoregions using geomorphology, vegetation, soil, geology, and plant diversity maps was revised using topography, vegetation, precipitation, and soil maps. Our new ecoregion map consists of 19 units that are unique in terms of landscape characteristics and has been adjusted to the current official boundary map of Cerrado. Some of the ecoregions consist of only one geomorphological compartment, whereas others are heterogeneous, consisting of up to eight compartments. Ferralsols comprise the dominant soil type in 14 of the ecoregions. The percentage of protected areas within ecoregions ranges from 1.7% to 51.5%. The most endangered ecoregion, where land use change critically threatens habitat integrity, is the Depressão Cárstica do São Francisco (states of Bahia, Minas Gerais, and Piauí), where environmental liability along riparian permanent protection areas amounts to 85.6% of the total area. Our proposed ecoregion map provides a spatial framework for regional and local assessments to improve decision-making processes to reconcile conservation and restoration planning, sustainable agriculture, and provision of ecosystem services. Besides de adjustment of the previous Cerrado's ecoregion map to the official biome boundary (relevant for the implementation of public policies of conservation as those regulated by the Brazilian Forest Code), the new analyses of the ecoregion map represent a substantial improvement in comparison to the ones conducted by the previous study in 2003. In addition, current web resources allow us to make all the information used or derived from this study available to other users. This opens the possibility of additional improvements of our findings by the scientific community or to be used effectively by decision makers.


Assuntos
Ecossistema , Pradaria , Agricultura , Biodiversidade , Brasil , Conservação dos Recursos Naturais
5.
Braz. j. infect. dis ; Braz. j. infect. dis;21(4): 369-375, July-Aug. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-888885

RESUMO

Abstract Introduction: Despite the high rate of tuberculosis indicators in Brazil, the Federal District shows a low prevalence of the disease. Objective: To analyze the relationship between climatic factors and air quality with tuberculosis in the Brazilian Federal District. Methodology: This was an ecological and descriptive study comparing 3927 new cases of Tuberculosis registered at the Federal District Tuberculosis Control Program with data from the National Institute of Meteorology, Brazilian Institute of Geography and Statistics, Brazilian Agricultural Research Institute, Brasilia Environmental Institute, and the Federal District Planning Company. Results: From 2003 to 2012, there has been a higher incidence of Tuberculosis (27.0%) in male patients in the winter (27.2%). Patients under 15 years of age (28.6%) and older than 64 years (27.1%) were more affected in the fall. For youth and adults (15-64 years), the highest number of cases was reported during winter (44.3%). The disease was prevalent with ultraviolet radiation over 17 MJ/m2 (67.8%; p = <0.001); relative humidity between 31.0% and 69.0% (95.8% of cases; p = <0.00); 12 h of daily sunlight or more (40.6%; p = 0.001); and temperatures between 20 °C and 23 °C (72.4%; p = <0.001). In the city of Taguatinga and surrounding area, pollution levels dropped to 15.2% between 2003 and 2012. Smoke levels decreased to 31.9%. In the Sobradinho region, particulate matter dropped to 13.1% and smoke to 19.3%, coinciding with the reduction of Tuberculosis incidence rates during the same period. Conclusion: The results should guide surveillance actions for Tuberculosis control and elimination and indicate the need to expand observation time to new climate indicators and air quality.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Tuberculose Pulmonar/etiologia , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Estações do Ano , Tuberculose Pulmonar/epidemiologia , Brasil/epidemiologia , Incidência
6.
Braz J Infect Dis ; 21(4): 369-375, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28545939

RESUMO

INTRODUCTION: Despite the high rate of tuberculosis indicators in Brazil, the Federal District shows a low prevalence of the disease. OBJECTIVE: To analyze the relationship between climatic factors and air quality with tuberculosis in the Brazilian Federal District. METHODOLOGY: This was an ecological and descriptive study comparing 3927 new cases of Tuberculosis registered at the Federal District Tuberculosis Control Program with data from the National Institute of Meteorology, Brazilian Institute of Geography and Statistics, Brazilian Agricultural Research Institute, Brasilia Environmental Institute, and the Federal District Planning Company. RESULTS: From 2003 to 2012, there has been a higher incidence of Tuberculosis (27.0%) in male patients in the winter (27.2%). Patients under 15 years of age (28.6%) and older than 64 years (27.1%) were more affected in the fall. For youth and adults (15-64 years), the highest number of cases was reported during winter (44.3%). The disease was prevalent with ultraviolet radiation over 17MJ/m2 (67.8%; p=<0.001); relative humidity between 31.0% and 69.0% (95.8% of cases; p=<0.00); 12h of daily sunlight or more (40.6%; p=0.001); and temperatures between 20°C and 23°C (72.4%; p=<0.001). In the city of Taguatinga and surrounding area, pollution levels dropped to 15.2% between 2003 and 2012. Smoke levels decreased to 31.9%. In the Sobradinho region, particulate matter dropped to 13.1% and smoke to 19.3%, coinciding with the reduction of Tuberculosis incidence rates during the same period. CONCLUSION: The results should guide surveillance actions for Tuberculosis control and elimination and indicate the need to expand observation time to new climate indicators and air quality.


Assuntos
Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Tuberculose Pulmonar/etiologia , Adolescente , Adulto , Brasil/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estações do Ano , Tuberculose Pulmonar/epidemiologia , Adulto Jovem
7.
São Paulo; s.n; 2015. 62 p. ilus, tab. (BR).
Tese em Português | LILACS, BBO - Odontologia | ID: biblio-867897

RESUMO

O objetivo deste estudo foi avaliar os parâmetros clínicos periodontais: profundidade clínica de sondagem, nível clínico de inserção e sangramento a sondagem e os níveis de IL-17, M-CSF, GM-CSF, MCP-1, ICAM-1 IL-8, IL-10, IL-1?, TNF-?, IL-4 no fluido gengival de pacientes portadores de periodontite agressiva, comparando esses valores aos dados obtidos de sujeitos periodontalmente saudáveis, além de comparar os dados clínicos e imunológicos iniciais aos obtidos após um ano de tratamento nos pacientes com periodontite agressiva. Foram selecionados 37 pacientes portadores de periodontite agressiva e oito pacientes periodontalmente saudáveis, utilizados como grupo controle. Após a realização do exame clínico periodontal em todos os dentes, foi escolhido um sítio profundo de cada paciente com paeriodontite e um sítio raso dos pacientes saudáveis para coleta do fluido gengival. Todos os pacientes receberam tratamento periodontal que consistiu de orientação de higiene bucal, raspagens, remoção de fatores de retenção do biofilme bacteriano, polimento e uso de antibióticos. As amostras obtidas foram processadas e analisadas com um painel de 10 citocinas através de um ensaio multiplex. As análises estatísticas mostraram que não houve diferença estatisticamente significante entre os doentes e os saudáveis em relação a GM-CSF, IL-4, IL-8 e MCP-1.


Quando foi feita a comparação longitudinal dos pacientes com periodontite agressiva, houve aumento após o tratamento para GM-CSF, ICAM-1, IL-4, IL-10, IL-17, MCP-1 e TNF-?. Com isso, pode-se concluir que mesmo após o tratamento periodontal com consultas trimestrais de manutenção e melhora dos parâmetros clínicos nos pacientes com PA que tinham um baseline mais inflamado, foi observado que alguns biomarcadores continuaram elevados, o que pode significar que esses pacientes continuam a apresentar atividade de doença ou que alguns desses biomarcadores não têm significância clínica para esses pacientes.


The aim of this study was to evaluate the periodontal clinical parameters: clinical probing depth, clinical attachment level and bleeding on probing and the IL-17, M-CSF, GM-CSF, MCP-1, ICAM-1, IL-8, IL-10, IL-1?, TNF-? and IL-4 levels in gingival crevicular fluid of aggressive periodontitis subjects, comparing these values with some data obtained from periodontal healthy patients, and also comparing clinic and immunologic initial data with the obtained after one year of treatment of aggressive periodontitis. The sample had 37 patients with aggressive periodontitis and 8 subjects clinically healthy, as control group. After the full periodontal examination, each patient with periodontitis had a deep site chosen, and a shallow site of the healthy ones, for collecting gingival fluid. All patients received periodontal treatment with oral hygiene, scaling, removal of retention factors, polishing and antibiotics. The obtained samples were processed and analyzed with a panel of 10 cytokines through a multiplex test. The statistical analyzes showed that there was no significant statistical difference between subjects with PA and healthy subjects with regard to GM-CSF, IL-4, IL-8 and MCP-1 levels.When longitudinal comparison of the subjects was made, it was noted some increase for GM-CSF, ICAM-1, IL-4, IL-10, IL-17, MCP-1 and TNF-?. Then, it can be concluded that, even after the periodontal treatment with trimestral maintenance and improvement on the clinical parameters, some biomarkers are still elevated, what can mean one of those possibilities: or the patients are still presenting some activity of the disease, or that some of these biomarkers don't have any clinical significance for this patients.


Assuntos
Humanos , Masculino , Feminino , Biomarcadores , Citocinas/administração & dosagem , Citocinas/uso terapêutico , Periodontite Agressiva/classificação , Periodontite Agressiva/complicações , Periodontite Agressiva/diagnóstico
8.
J Clin Periodontol ; 41(10): 943-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25070874

RESUMO

AIMS: To evaluate the association among serum immunoglobulin G (IgG) responses to Aggregatibacter actinomycetemcomitans (Aa) serotypes a, b and c, Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf) and clinical parameters in Aggressive Periodontitis (AP) subjects. Associations between periodontal pathogens and clinical and immunological parameters were also evaluated. METHODS: Thirty-eight subjects diagnosed with generalized AP (GAP) and localized AP (LAP) were included. Ten healthy controls were also evaluated. Clinical parameters were assessed and percentages of subgingival levels of Aa, Pg and Tf (beyond bacterial load), were determined by quantitative real-time polymerase chain reaction. Serum IgG antibody levels against Aa, Pg and Tf were evaluated by enzyme-linked immunosorbent assay. RESULTS: Percentages of Aa, Pg and Tf were significantly higher in AP than in controls. The response to Aa serotype c was higher in LAP subjects than in controls. There were no differences in microbial composition or antibodies responses between GAP and LAP, except for IgG response to Tf. Pg levels were correlated with probing depth (PD), BoP and CAL in GAP but not in LAP subjects. Tf levels correlated with PD and CAL in GAP subjects. In GAP, the infection levels of Aa and Pg correlated with the corresponding IgG levels to Aa serotype c and Pg. CONCLUSION: Given the evidences that IgG response in AP patients correlated with bacterial infection level in GAP, but not in LAP, and that LAP patients lack a response to Tf, despite harbouring this species, our data suggest a difference in host immune defence between these two forms of aggressive periodontitis.


Assuntos
Periodontite Agressiva/microbiologia , Anticorpos Antibacterianos/sangue , Bactérias Gram-Negativas/imunologia , Imunoglobulina G/sangue , Adulto , Aggregatibacter actinomycetemcomitans/classificação , Aggregatibacter actinomycetemcomitans/imunologia , Periodontite Agressiva/classificação , Periodontite Agressiva/imunologia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/microbiologia , Carga Bacteriana , Bacteroides/classificação , Bacteroides/imunologia , Estudos Transversais , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , Perda da Inserção Periodontal/imunologia , Perda da Inserção Periodontal/microbiologia , Bolsa Periodontal/imunologia , Bolsa Periodontal/microbiologia , Porphyromonas gingivalis/classificação , Porphyromonas gingivalis/imunologia , Radiografia , Sorogrupo , Adulto Jovem
9.
An Acad Bras Cienc ; 82(4): 1085-94, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21152778

RESUMO

The Cerrado region, with over 50 million hectares of cultivated pasture, provides 55% of Brazilian beef production. Previous investigations have shown that about 70-80% of this pasture is affected by some kind of degradation, leading to low productivity. However, until now, few surveys have been carried out on a regional scale. The aim of the present work is both to assess the fertility and acidity levels of Cerrado soils under pasture and compare the variability of the soils characteristics on a regional scale. Two soil depths were sampled in different places within the studied area: (1) a surface horizon (0.0-0.2 m) in order to evaluate its fertility and acidity status for pasture, and (2) a subsurface horizon (0.6-0.8 m), used for classification. Most of soils had levels of nutrients below the reference values for adequate pasture development. Whatever the texture, about 90% of soils had low or very low availability of phosphorus. Only 7 to 14% of soils had low pH, high exchangeable aluminum, and aluminum saturation above the critical acidity level. Except for nitrogen, no significant difference was found between Latossolos Vermelhos and Latossolos Vermelho-Amarelos.


Assuntos
Agricultura , Fenômenos Químicos , Monitoramento Ambiental/métodos , Solo/química , Animais , Brasil , Bovinos , Fertilizantes
10.
An. acad. bras. ciênc ; 82(4): 1085-1094, Dec. 2010. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-567814

RESUMO

The Cerrado region, with over 50 million hectares of cultivated pasture, provides 55 percent of Brazilian beef production. Previous investigations have shown that about 70-80 percent of this pasture is affected by some kind of degradation, leading to low productivity. However, until now, few surveys have been carried out on a regional scale. The aim of the present work is both to assess the fertility and acidity levels of Cerrado soils under pasture and compare the variability of the soils characteristics on a regional scale. Two soil depths were sampled in different places within the studied area: (1) a surface horizon (0.0-0.2 m) in order to evaluate its fertility and acidity status for pasture, and (2) a subsurface horizon (0.6-0.8 m), used for classification. Most of soils had levels of nutrients below the reference values for adequate pasture development. Whatever the texture, about 90 percent of soils had low or very low availability of phosphorus. Only 7 to 14 percent of soils had low pH, high exchangeable aluminum, and aluminum saturation above the critical acidity level. Except for nitrogen, no significant difference was found between Latossolos Vermelhos and Latossolos Vermelho-Amarelos.


A região do Cerrado, com 50 milhões de hectares de pastagens cultivadas, responde por 55 por cento da carne bovina produzida no Brasil. Há estimativas indicando que entre 70 e 80 por cento destas pastagens apresentam algum grau de degradação, o que leva a baixa produtividade. No entanto, até o presente, poucos trabalhos foram desenvolvidos em escala regional. O objetivo deste trabalho foi avaliar a fertilidade e a acidez de Latossolos sob pastagens na região do Cerrado e comparar a variabilidade das características dos solos em escala regional. A amostragem foi realizada em duas profundidades, superficial (0,0-0,2 m) para avaliação da fertilidade e acidez e subsuperficial (0,60,8 m), utilizada para classificar os solos. A maioria dos solos apresentou teores de nutrientes abaixo do recomendado para o adequado desenvolviento das pastagens. Independentemente da textura, aproximadamente 90 por cento dos solos apresentaram baixa ou muito baixa disponibilidade de P. Apenas 7-14 por cento dos solos apresentaram baixo pH, alta saturação por Al e acidez acima do nível crítico. Exceto para o N, não houve diferença significativa nos níveis de fertilidade e acidez entre os Latossolos Vermelhos e os Latossolos Vermelho-Amarelos.


Assuntos
Animais , Bovinos , Agricultura , Fenômenos Químicos , Monitoramento Ambiental/métodos , Solo/química , Brasil , Fertilizantes
11.
Semina Ci. agr. ; 28(2): 167-178, 2007.
Artigo em Português | VETINDEX | ID: vti-470586

RESUMO

The aim of the present work was to characterize the soils solution and to examine Als speciation in soils under pasture in Brazilian Cerrado region. The soils used in this study were collected in the space between the towns of Goiânia, GO and Barra do Garças, MT, to the margins of GO 060 and BR 154 highways. For the collection of soil solutions it was used a special equipment built with a PVC tube whose inferior extremity was coupled to a porous tip of special ceramic. To quantify the aluminum ionic species, two methods were used: chemical method of aluminon and the method WHAM (geochemical speciation model). The results allowed to conclude that the predominant aluminum ionic species varied in function of soil type, pH and concentration of NO3- in the soil solution. More abundant Als species in the soils were Al-M.O., Al3+ and Al(OH)4- , in this order.


  O objetivo deste trabalho foi caracterizar a solução de solos e avaliar a especiação do Al em solos sob pastagens no Bioma Cerrado. Para a coleta das soluções dos solos utilizou-se tubo de PVC com a extremidade inferior acoplada a uma ponta porosa de cerâmica especial. Para quantificar as formas iônicas do alumínio, foram comparadas duas metodologias: método químico do aluminon e o método WHAM (modelo geoquímico de especiação). Os solos utilizados no presente estudo foram coletados às margens das rodovias GO 060 e BR 154, no trecho entre os municípios de Goiânia, GO e Barra do Garças, MT. Os resultados permitiram concluir que as espécies iônicas de alumínio predominantes variaram em função do tipo de solo, pH e concentração de NO3- na solução do solo. Verificou-se também que as espécies iônicas mais abundantes foram: Al-M.O., Al3+ e Al(OH)4-

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