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1.
Environ Monit Assess ; 196(4): 385, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38507123

ABSTRACT

Soil quality monitoring in mining rehabilitation areas is a crucial step to validate the effectiveness of the adopted recovery strategy, especially in critical areas for environmental conservation, such as the Brazilian Amazon. The use of portable X-ray fluorescence (pXRF) spectrometry allows a rapid quantification of several soil chemical elements, with low cost and without residue generation, being an alternative for clean and accurate environmental monitoring. Thus, this work aimed to assess soil quality in mining areas with different stages of environmental rehabilitation based on predictions of soil fertility properties through pXRF along with four machine learning algorithms (projection pursuit regression, PPR; support vector machine, SVM; cubist regression, CR; and random forest, RF) in the Eastern Brazilian Amazon. Sandstone and iron mines in different chronological stages of rehabilitation (initial, intermediate, and advanced) were evaluated, in addition to non-rehabilitated and native forest areas. A total of 81 soil samples (26 from sandstone mine and 55 from iron mine) were analyzed by both traditional wet-chemistry methods and pXRF. The available/exchangeable contents of K, Ca, B, Fe, and Al, in addition to H+Al, cation exchange capacity at pH = 7, Al saturation, soil organic matter, pH, sum of bases, base saturation, clay, and sand were accurately predicted (R2 > 0.70) using pXRF data, with emphasis on the prediction of Fe (R2 = 0.93), clay content (R2 = 0.81), H+Al (R2 = 0.81), and K+ (R2 = 0.85). The best predictive models were developed by RF and CR (86%) and when considering pXRF data + mining area + stage of rehabilitation (73%). The results highlight the potential of pXRF to accurately assess soil properties in environmental rehabilitation areas in the Amazon region (yet scarcely evaluated under this approach), promoting a more agile and cheaper preliminary diagnosis compared to traditional methods.


Subject(s)
Soil Pollutants , Soil , Soil/chemistry , Clay , Brazil , Environmental Monitoring/methods , Soil Pollutants/analysis , Iron/analysis
2.
Environ Res ; 236(Pt 1): 116753, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37500037

ABSTRACT

Farms use large quantities of fertilizers from many sources, making quality control a challenging task, as the traditional wet-chemistry analyses are expensive, time consuming and not environmentally-friendly. As an alternative, this work proposes the use of portable X-ray fluorescence (pXRF) spectrometry and machine learning algorithms for rapid and low-cost estimation of macro and micronutrient contents in mineral and organic fertilizers. Four machine learning algorithms were tested. Whole (i.e., as delivered by the manufacturer) (CP) and ground (AQ) samples (429 in total) were analyzed to test the effect of fertilizer granulometry in prediction performance. Model validation indicated highly accurate predictions of macro (N: R2 = 0.92; P: 0.97; K: 0.99; Ca: 0.94, Mg: 0.98; S: 0.96) and micronutrients (B: 0.99; Cu: 0.99; Fe: 0.98; Mn: 0.91; Zn: 0.94) for both organic and mineral fertilizers. RPD values ranged from 2.31 to 9.23 for AQ samples, and Random Forest and Cubist Regression were the algorithms with the best performances. Even samples analyzed as they were received from the manufacturer (i.e., no grinding) provided accurate predictions, which accelerate the confirmation of nutrient contents contained in fertilizers. Results demonstrated the potential of pXRF data coupled with machine learning algorithms to assess nutrient composition in both mineral and organic fertilizers with high accuracy, allowing for clean, fast and accurate quality control. Sensor-driven quality assessment of fertilizers improves soil and plant health, crop management efficiency and food security with a reduced environmental footprint.

3.
Foods ; 12(11)2023 May 23.
Article in English | MEDLINE | ID: mdl-37297337

ABSTRACT

Pereskia aculeata Miller is an edible plant species belonging to the Cactaceae family. It has the potential to be used in the food and pharmaceutical industries due to its nutritional characteristics, bioactive compounds, and mucilage content. Pereskia aculeata Miller is native to the Neotropical region, where it is traditionally employed as food in rural communities, being popularly known as 'ora-pro-nobis' (OPN) or the Barbados gooseberry. The leaves of OPN are distinguished by their nontoxicity and nutritional richness, including, on a dry basis, 23% proteins, 31% carbohydrates, 14% minerals, 8% lipids, and 4% soluble dietary fibers, besides vitamins A, C, and E, and phenolic, carotenoid, and flavonoid compounds. The OPN leaves and fruits also contain mucilage composed of arabinogalactan biopolymer that presents technofunctional properties such as thickener, gelling, and emulsifier agent. Moreover, OPN is generally used for pharmacological purposes in Brazilian folk medicine, which has been attributed to its bioactive molecules with metabolic, anti-inflammatory, antioxidant, and antimicrobial properties. Therefore, in the face of the growing research and industrial interests in OPN as a novel food source, the present work reviews its botanical, nutritional, bioactive, and technofunctional properties, which are relevant for the development of healthy and innovative food products and ingredients.

4.
Plants (Basel) ; 12(3)2023 Jan 26.
Article in English | MEDLINE | ID: mdl-36771645

ABSTRACT

Several materials have been characterized using proximal sensors, but still incipient efforts have been driven to plant tissues. Eucalyptus spp. cultivation in Brazil covers approximately 7.47 million hectares, requiring faster methods to assess plant nutritional status. This study applies portable X-ray fluorescence (pXRF) spectrometry to (i) distinguish Eucalyptus clones using pre-processed pXRF data; and (ii) predict the contents of eleven nutrients in the leaves of Eucalyptus (B, Ca, Cu, Fe, K, Mg, Mn, N, P, S, and Zn) aiming to accelerate the diagnosis of nutrient deficiency. Nine hundred and twenty samples of Eucalyptus leaves were collected, oven-dried, ground, and analyzed using acid-digestion (conventional method) and using pXRF. Six machine learning algorithms were trained with 70% of pXRF data to model conventional results and the remaining 30% were used to validate the models using root mean square error (RMSE) and coefficient of determination (R2). The principal component analysis clearly distinguished developmental stages based on pXRF data. Nine nutrients were accurately predicted, including N (not detected using pXRF spectrometry). Results for B and Mg were less satisfactory. This method can substantially accelerate decision-making and reduce costs for Eucalyptus foliar analysis, constituting an ecofriendly approach which should be tested for other crops.

5.
Environ Res ; 221: 115300, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36649846

ABSTRACT

Ca and Mg are the most important chemical elements in lime. Properly measuring Ca and Mg contents is essential to assess the quality of lime products. Quality control guarantees the adequate use of lime in industrial processes, in soils, and helps avoiding adulteration. Proximal sensors can aid in this process by determining Ca and Mg contents easily, rapidly and without producing chemical waste. The objective of this study was to evaluate the use an environmentally-friendly method of analyzing the quality of lime. We studied 1) the use of portable X-ray fluorescence (pXRF) to predict concentrations of Ca and Mg in lime, 2) tested if NixPro™ sensor can improve prediction accuracy and 3) tested if sample preparation methods (grinding) affect analyses. 74 samples of lime were analyzed by two different laboratories (lab. 1 = 38, lab. 2 = 36). All samples submitted to pXRF and NixPro™ analyses. Sensor analyses were done in whole (CP) and ground (AQ) samples to test the effect of sample preparation in prediction performance. High correlation was found between Ca and Mg contents measured via pXRF and laboratory analyses. Mg-CP presented the highest correlation coefficient (r = 0.81); Mg-AQ, the lowest (0.57). Predictions presented good performance (R2 > 0.68); Mg had the best results (0.86). Separating models per laboratory showed that some datasets are harder to model, probably due to variability in the source material (limestone). The addition of NixPro™ data contributed to improve prediction accuracy, although slightly. Predictions using CP samples presented the best results, especially for Mg, indicating that grinding is not necessary. This pioneer study demonstrated that fused proximal sensors can be used to rapidly and easily determine contents of Ca and Mg in soil amendments without producing chemical waste.


Subject(s)
Calcium , Soil Pollutants , Calcium/analysis , Magnesium/analysis , Soil Pollutants/analysis , Environmental Monitoring/methods , Spectrometry, X-Ray Emission/methods , Soil/chemistry
6.
Foods ; 11(22)2022 Nov 12.
Article in English | MEDLINE | ID: mdl-36429200

ABSTRACT

Macauba palm fruits (Acrocomia aculeata and Acrocomia totai) are emerging as sources of high-quality oils from their pulp and kernels. The protein-rich macauba kernel meal (MKM) left after oil extraction remains undervalued, mainly due to the lack of suitable deoiling parameters and integrated protein recovery methods. Therefore, the present study aimed to produce protein concentrates from MKM using sieve fractionation. The deoiling parameters, comprising pressing, milling, and solvent extraction, were improved in terms of MKM functionality. The combination of hydraulic pressing, milling to 1 mm, and the hexane extraction of A. aculeata kernels resulted in MKM with the highest protein solubility (77.1%), emulsifying activity index (181 m2/g protein), and emulsion stability (149 min). After sieve fractionation (cut size of 62 µm), this meal yielded a protein concentrate with a protein content of 65.6%, representing a 74.1% protein enrichment compared to the initial MKM. This protein concentrate showed a reduced gelling concentration from 8 to 6%, and an increased emulsion stability from 149 to 345 min, in comparison to the MKM before sieving. Therefore, sieve fractionation after improved deoiling allows for the simple, cheap, and environmentally friendly recovery of MKM proteins, highlighting the potential of macauba kernels as a new source of protein.

7.
An Acad Bras Cienc ; 93(4): e20200646, 2021.
Article in English | MEDLINE | ID: mdl-34550165

ABSTRACT

Portable X-ray fluorescence (pXRF) spectrometry offers valuable information for prediction models of soil fertility attributes spatial variation, although this approach is yet scarce in tropical regions. This study aims to predict and build spatial variability maps of soil pH, remaining phosphorus (P-Rem), soil organic matter (SOM) and sum of bases (SB) using pXRF results through stepwise multiple linear regression (SMLR) and Random Forest (RF) in a highly variable tropical area. Composite samples from soil A horizon were collected at 90 points throughout the campus of the Federal University of Lavras, Minas Gerais, Brazil, for pH, P-Rem, SOM, SB and pXRF analyses. RF predictions showed the highest accuracies, especially for P-Rem and SB (R² values of 0.66 and 0.55, respectively). Attributes that showed higher R² in punctual predictions also exhibited higher R² in spatial predictions. Data obtained from pXRF in tandem with RF can be used to assist prediction models for soil fertility attributes, consequently enabling the digital mapping of such attributes and helping to improve the knowledge about the spatial variability of such attributes in soils of tropical climate. This technique can therefore assist in the identification and orientation of adequate management practices in tropical agricultural practices.


Subject(s)
Soil Pollutants , Soil , Agriculture , Environmental Monitoring , Soil Pollutants/analysis , Spectrometry, X-Ray Emission
8.
Ciênc. agrotec., (Impr.) ; 42(1): 80-92, Jan.-Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-890664

ABSTRACT

ABSTRACT Portable X-ray fluorescence spectrometer (pXRF) has been recently adopted by the Soil Science community for uses in both field and laboratory, obtaining the total content of several chemical elements in a few seconds. Sulfuric acid digestion is an expensive and time-consuming laboratory analysis that provides contents of Fe2O3, Al2O3, SiO2, TiO2 and P2O5, important for soil studies. Due to few pXRF studies in tropical soils, this work aimed to compare contents of Fe2O3, Al2O3, SiO2, TiO2 and P2O5 obtained by pXRF with sulfuric acid digestion results, and to evaluate the effects of varying forms of preparing soil samples and scanning with pXRF on the resulting values in Brazilian soils. Soils were scanned in five conditions in-field (in situ) and in laboratory, evaluating varying sample preparation methods, particle sizes and soil moisture. Four pXRF scanning operational modes were tested. Linear regressions were adjusted between results of pXRF and sulfuric acid digestion. Equations were validated with an independent set of samples. Statistical analyses compared the methods of preparing the samples. Adequate linear models reached R2 of 0.99 and 0.89 for Fe2O3 and TiO2, respectively. Validation promoted R2 greater than 0.97 and RMSE and ME close to zero for both oxides. Statistical differences of pXRF results were found among the methods of preparing samples. pXRF spectrometer has great potential to obtain Fe2O3 and TiO2 content rapidly and economically with high correspondence with laboratory results of sulfuric acid digestion analysis. Varying methods of preparing the samples promote differences in the results of pXRF.


RESUMO O espectrômetro portátil de fluorescência de raios-X (pXRF) foi recentemente adotado pela Ciência do Solo, para uso em campo e laboratório, para obtenção do conteúdo total de vários elementos químicos em poucos segundos. A digestão com ácido sulfúrico é uma análise laboratorial cara e demorada que fornece teores de Fe2O3, Al2O3, SiO2, TiO2 e P2O5, importantes para estudos sobre solos. Devido aos poucos estudos sobre o pXRF em solos tropicais, este trabalho objetivou comparar os teores de Fe2O3, Al2O3, SiO2, TiO2 e P2O5 obtidos pelo pXRF com os resultados de digestão com ácido sulfúrico e avaliar os efeitos de diferentes formas de preparo de amostras de solo e leitura com o pXRF sobre seus resultados para solos brasileiros. Os solos foram submetidos a leituras com o pXRF em cinco condições, em campo (in situ) e em laboratório, avaliando variados métodos de preparo de amostras, tamanhos de partículas e umidade do solo. Quatro modos de operação do pXRF foram testados. Regressões lineares foram ajustadas entre os resultados do pXRF e digestão com ácido sulfúrico. As equações foram validadas com um conjunto independente de amostras. Análises estatísticas compararam os métodos de leitura de amostras. Modelos lineares adequados atingiram R2 de 0,99 e 0,89 para Fe2O3 e TiO2, respectivamente. A validação promoveu R2 maior que 0.97 e RMSE e ME próximos a zero para ambos os óxidos. Foram encontradas diferenças estatísticas dos resultados do pXRF entre os métodos de preparo de amostras. O pXRF possui um grande potencial para obter rápida e economicamente os teores de Fe2O3 e TiO2 com elevada correspondência com os resultados laboratoriais da análise da digestão com ácido sulfúrico. Métodos variáveis ​​de preparo das amostras promovem diferenças nos resultados de pXRF.

9.
Ciênc. agrotec., (Impr.) ; 41(6): 648-664, Nov.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-890655

ABSTRACT

ABSTRACT Determination of soil properties ​​helps in the correct management of soil fertility. The portable X-ray fluorescence spectrometer (pXRF) has been recently adopted to determine total chemical element contents in soils, allowing soil property inferences. However, these studies are still scarce in Brazil and other countries. The objectives of this work were to predict soil properties using pXRF data, comparing stepwise multiple linear regression (SMLR) and random forest (RF) methods, as well as mapping and validating soil properties. 120 soil samples were collected at three depths and submitted to laboratory analyses. pXRF was used in the samples and total element contents were determined. From pXRF data, SMLR and RF were used to predict soil laboratory results, reflecting soil properties, and the models were validated. The best method was used to spatialize soil properties. Using SMLR, models had high values of R² (≥0.8), however the highest accuracy was obtained in RF modeling. Exchangeable Ca, Al, Mg, potential and effective cation exchange capacity, soil organic matter, pH, and base saturation had adequate adjustment and accurate predictions with RF. Eight out of the 10 soil properties predicted by RF using pXRF data had CaO as the most important variable helping predictions, followed by P2O5, Zn and Cr. Maps generated using RF from pXRF data had high accuracy for six soil properties, reaching R2 up to 0.83. pXRF in association with RF can be used to predict soil properties with high accuracy at low cost and time, besides providing variables aiding digital soil mapping.


RESUMO A determinação de atributos do solo auxilia no correto manejo da sua fertilidade. O equipamento portátil de fluorescência de raios-X (pXRF) foi recentemente adotado para determinar o teor total de elementos químicos em solos, permitindo inferências sobre atributos do solo. No entanto, esses estudos ainda são escassos no Brasil e em outros países. Os objetivos deste trabalho foram prever atributos do solo a partir de dados do pXRF, comparando-se os métodos de regressão linear múltipla stepwise (SMLR) e de random forest (RF), além de mapear e validar atributos do solo. 120 amostras de solo foram coletadas em três profundidades e submetidas a análises laboratoriais. Utilizou-se o pXRF para leitura das amostras e determinou-se o teor total de elementos. A partir dos dados do pXRF, foram utilizadas SMLR e RF para predizer resultados laboratoriais, que refletem atributos do solo, e os modelos foram validados. O melhor método foi utilizado para espacializar os atributos do solo. Utilizando SMLR, os modelos apresentaram valores elevados de R² (≥0,8), porém maior acurácia foi obtida na modelagem com RF. A capacidade de troca de cátions potencial e efetiva, matéria orgânica do solo, pH, saturação por bases e teores trocáveis de Ca, Al e Mg apresentaram ajustes adequados e predições acuradas com RF. Dos dez atributos do solo preditos por RF a partir de dados do pXRF, sete apresentavam CaO como a variável mais importante para auxiliar as predições, seguido por P2O5, Zn e Cr. Os mapas gerados a partir de dados do pXRF usando RF apresentaram adequados valores de R² para seis atributos do solo, atingindo R2 de até 0,83. O pXRF em associação com RF pode ser usado para prever atributos do solo com elevada acurácia, com rapidez e a baixo custo, além de proporcionar variáveis que auxiliam o mapeamento digital de solos.

10.
Ciênc. agrotec., (Impr.) ; 41(4): 413-427, July-Aug. 2017. tab, graf
Article in English | LILACS | ID: biblio-890634

ABSTRACT

ABSTRACT In Brazil, the Mantiqueira Range, southeastern region, shelters the last remnants of the ecologically important Upper Montane Tropical Forest. since extensive exploration that has been taking place in this biome for decades, the influence of land-use changes on hydropedology in these areas must be investigated once major land-use changes have been observed. This study aims to evaluate the land-use influence on soil drainable porosity (SDP) in a headwater watershed located in the Mantiqueira Range region, and to validate the proposed methods based on micromorphological and hydrological indicators. The native vegetation of the study area is Atlantic forest that occupies 62% of the area, and the remaining 38% has been used for pasture. Thirty nine combinations of environmental variables were tested, each one generating a map for predicting SDP. The performance of the spatial prediction of SDP was assessed using 20% of the data from the total number of samples collected throughout the watershed. The least values of SDP are due to the process of removal of native forest and replacement by pasture. Areas with high to moderate SDP are associated with native forest fragments demonstrating the effects of the Atlantic Forest on the water infiltration and groundwater recharge processes, given by the greater contribution of baseflow in a forested catchment located within the studied watershed. The analysis of soil micromorphological images provided useful supporting information on the soil porosity system and along with hydrological properties of the watershed helped understand the SDP behavior on subsurface and groundwater storage capacity.


RESUMO No Brasil, a Serra da Mantiqueira, abriga um dos últimos remanescentes da Floresta Tropical de Altitude. Devido a grande exploração que vem ocorrendo neste bioma há décadas, a influência na hidropedologia decorrente das mudanças do uso do solo deve ser investigada. O objetivo deste estudo foi avaliar a influência do uso do solo na porosidade drenável do solo (PDS) em uma bacia hidrográfica localizada na região da Serra da Mantiqueira e validar os métodos propostos com base em indicadores micromorfológicos e hidrológicos. A vegetação nativa da área de estudo é a Mata Atlântica que ocupa 62% da área, e com os 38% restantes utilizados para pastagem. Trinta e nove combinações de variáveis ​​ambientais foram testadas, cada uma gerando um mapa para predizer a PDS. O desempenho da predição espacial da PDS foi avaliado utilizando 20% dos dados do número total de amostras coletadas em toda a bacia hidrográfica. Os menores valores de PDS são devidos ao processo de remoção de floresta nativa e substituição por pastagem. Áreas com altos a moderados valores de PDS estão associadas a fragmentos de florestas nativas que demonstram os efeitos da Mata Atlântica nos processos de infiltração de água e de recarga de água subterrânea na região da Mantiqueira, dada a maior contribuição do fluxo base em áreas florestadas. A análise micromorfológica do solo forneceu informações úteis sobre o sistema poroso do solo e as propriedades hidrológicas da bacia hidrográfica, ajudando a entender o comportamento da PDS e a capacidade de armazenamento em subsuperfícíe.

11.
Ciênc. agrotec., (Impr.) ; 41(3): 245-254, May.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-890621

ABSTRACT

ABSTRACT The X-ray fluorescence (XRF) is an analytical technique for determination of elemental composition of different materials. In soils, the XRF has many pedological, environmental and agronomic applications, mainly after the emergence of portable equipments (pXRF). This technique has been recently adopted and successfully used for soil characterization worldwide, but very rare works have been carried out in soils of developing countries. The soil characterization includes the complete elemental composition determination (nutrients, trace and rare-earth elements) and allows estimating some soil physical and chemical properties. In Brazil, this technique is still incipient, mainly the use of pXRF, however, it can greatly contribute to soil characterization in-field or in-lab conditions and also replacing methods of soil analyses considered non-environmentally friendly. This review summarizes the XRF technique including principles and the main applications of pXRF in soils highlighting its potential for tropical Soil Science.


RESUMO Fluorescência de raios-X (FRX) é uma técnica analítica para determinação da composição elementar de diferentes materiais. Em solos, a FRX apresenta muitas aplicações pedológicas, ambientais e agronômicas, principalmente após a emergência de equipamentos portáteis (pXRF). Essa técnica tem sido utilizada com sucessso no mundo todo para caracterização do solo, entretanto, são raros os trabalhos em solos de países em desenvolvimento. A caracterização do solo inclui a determinação completa da composição elementar (nutrientes, elementos-traço e terras-raras) e permite a estimativa de atributos químicos e físicos do solo. No Brasil, a FRX é ainda incipiente, principalmente o uso do pXRF, entretanto, essa técnica pode contribuir grandemente para a caracterização do solo no campo, em condições laboratoriais e, também, substituindo alguns métodos de análise do solo considerados não prejudicial ao ambiente. Esta revisão sumariza a técnica de FRX incluindo princípios e as principais aplicações do pXRF, destacando seu potencial de uso na Ciência do Solo tropical.

12.
Ciênc. agrotec., (Impr.) ; 41(2): 209-219, Mar.-Apr. 2017. tab
Article in English | LILACS | ID: biblio-890611

ABSTRACT

ABSTRACT In the fertility management of highly weathered-leached Brazilian Oxisols, P is the most limiting macronutrient. A greenhouse experiment was conducted with the objective to evaluate the influence of the interaction between P doses, mycorrhizal inoculation and historical land use on Urochloa decumbens growth and P uptake in four Oxisols with contrasting chemical, physical and mineralogical properties. The plants were cultivated in plastic pots containing 4 kg of soil in a completely randomized design, four replications and 2x2x2 factorial scheme: with two P doses; with and without mycorrhizal inoculation; soils cultivated for long periods and non-cultivated (under native vegetation). There were two plantings of ten weeks each. Shoot dry mater, concentration and accumulation of P in the shoot were evaluated. In the first planting, the Urochloa response was greater in non-cultivated soils associated with inoculation and P addition. However, in the second planting, the inoculation had a greater effect in all soils compared to the first planting associated with the lowest P dose. As the P concentration in the soil increased, P in the shoot dry matter increases. The inoculation did not affect the P concentration and accumulation in the shoot of Urochloa. The growth of Urochloa decumbens was strongly influenced by the interaction among soil class x history of land use x dose of P x inoculation.


RESUMO No manejo da fertilidade de Latossolos brasileiros altamente intemperizados e lixiviados, o P é o macronutriente mais limitante. Assim, conduziu-se um experimento em casa de vegetação, objetivando-se avaliar a influência da interação entre doses de P, inoculação micorrízica e histórico de uso do solo no crescimento de Urochloa decumbens e absorção de P, em quatro Latossolos com atributos químicos, físicos e mineralógicos contrastantes. As plantas foram cultivadas em vasos contendo 4 kg de solo, dispostos em um delineamento inteiramente casualizado, com quatro repetições e esquema fatorial 2x2x2: duas doses de P; com e sem inoculação micorrízica; solos cultivados por longos períodos e não cultivados (sob vegetação nativa). Realizaram-se dois cultivos com duração de 10 semanas cada. Após cada cultivo avaliaram-se a matéria seca da parte aérea, teor e acúmulo de P na parte aérea. No primeiro cultivo, maior resposta ao P aconteceu nos solos sob vegetação nativa em associação à inoculação e adição de P. No segundo cultivo, a inoculação teve maior efeito em todos os solos, associada à menor dose de P. O aumento do P no solo aumenta a concentração desse nutriente na parte aérea. A inoculação não teve efeito na concentração e no acúmulo de P na parte aérea de Urochloa. O crescimento de Urochloa decumbens foi fortemente influenciado pela interação entre classe de solo x histórico de uso da terra x dose de P x inoculação.

13.
Epidemiol Serv Saude ; 25(3): 487-498, 2016.
Article in Portuguese | MEDLINE | ID: mdl-27869920

ABSTRACT

OBJECTIVE: to describe the proportion of duplicate records held on the Brazilian Notifiable Diseases Information System, 2008-2009. METHODS: identification of duplicate records of dengue, leprosy, visceral leishmaniasis and cutaneous leishmaniasis, meningitis and tuberculosis was conducted using Reclink III(r); the proportion of duplicate records was calculated by geographical region, state and municipal population size categories. RESULTS: visceral leishmaniasis (VL) and meningitis had higher proportions of duplicate notification (5.3% and 3.6%, respectively) whilst leprosy had the lowest (0.7%); the states with highest repetitions were Rio Grande do Norte (VL 6.8% and leprosy 5.1%), Rio de Janeiro (tuberculosis 2.5% and meningitis 4.9%) and Goiás (dengue 2.0% and meningitis 7.2%). CONCLUSION: the Northeast region had the highest proportion of duplicate records for four of the six diseases analyzed; with the exception of dengue, percentage repetition was lower in municipalities with larger population size.


Subject(s)
Data Collection/statistics & numerical data , Disease Notification/statistics & numerical data , Registries/statistics & numerical data , Brazil/epidemiology , Databases, Factual/statistics & numerical data , Dengue/epidemiology , Humans , Information Systems , Leishmaniasis/epidemiology , Leprosy/epidemiology , Meningitis/epidemiology , Tuberculosis, Pulmonary/epidemiology
14.
Suma psicol ; 16(2): 69-84, dic. 2009.
Article in Spanish | LILACS | ID: lil-539398

ABSTRACT

El objetivo del estudio fue adaptar el inventario de bienestar subjetivo de Nacpal y Shell para su empleo con jóvenes y adolescentes latinoamericanos. Se efectuó la equivalencia conceptual, semántica y operacional de la versión prototípica del instrumento. La versión definitiva fue administrada a una muestra de 1,891 jóvenes y adolescentes (730 mexicanos, 664 argentinos y 497 brasileros), quienes además respondieron una selección de reconocidos instrumentos desarrollados para explorar resiliencia, afrontamiento del estrés, sentido del humor, inteligencia emocional y valores culturales. El análisis de la validez factorial mostró una estructura de 6 factores que explicaron casi el 59% de la varianza total. La validez de constructo quedó demostrada a partir de las positivas y significativas correlaciones entre el bienestar subjetivo y la mayoría de las variables medidas. La confiabilidad del instrumento adaptado alcanzó niveles satisfactorios. A la luz de los resultados obtenidos, se efectúan algunas sugerencias para futuras investigaciones en el área.


The aim of this study was to adapt the Well-Being Inventory of Nacpal & Shell for using with Latinamerican youth and adolescents. The conceptual, semantic and operational equivalence of inventory prototype version was analized. The final version was administered to a sample of 1,891 students (730 Mexicans, 664 Argentines and 497 Brazilians) who also filled a set of recognized instruments developed to explore resilience, coping, sense of humor, emotional intelligence and cultural values.The exploration of factorial validity showed six orthogonal factors which explained almost 59% of total variance. Construct validity was demostrated through positive and significant correlations between subjective well-being and most of the variables considered. Reliability of the adapted instrument reached satisfactory levels. In light of the results some suggestions for future research in the area are made.


Subject(s)
Humans , Quality of Life/psychology , Child Labor/psychology
15.
Parasitol Res ; 104(5): 1197-201, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19096877

ABSTRACT

The in vitro schistosomicidal activity of curcumin (doses ranging from 5 to 100 microM) was carried out against Schistosoma mansoni adult worms. Curcumin (at 50 and 100 microM) caused death of all worms. When tested at the doses of 5 and 20 microM, it decreased the worm viability in comparison with negative (Roswell Memorial Park Institute (RPMI) 1640 medium alone or RPMI 1640 medium with 10% dimethyl sulfoxide) and positive (heat-killed worms at 56 degrees C or praziquantel 10 microM) control groups. All pairs of coupled adult worms were separated into individual male and female by the action of curcumin at the doses of 20 to 100 microM. When tested at 5 and 10 microM, curcumin reduced egg production by 50% in comparison with the positive control group. It is the first time that the schistosomicidal activity has been reported for curcumin.


Subject(s)
Antiprotozoal Agents/pharmacology , Curcumin/pharmacology , Schistosoma mansoni/drug effects , Animals , Female , Male , Oocysts/drug effects , Survival Analysis
16.
Braz. arch. biol. technol ; 48(6): 951-965, Nov. 2005. mapas, tab, graf
Article in English | LILACS | ID: lil-420446

ABSTRACT

O objetivo deste estudo foi descrever e comparar a sucessão das comunidades bentônicas da região entre-marés, em duas áreas na Baía de Guanabara, RJ, Brasil: Urca, uma área sujeita a moderado nível de poluição orgânica, e Catalão, uma área extremamente poluída. Em cada área, três transectos verticais foram raspados um mês antes do início do estudo, para se avaliar o recrutamento dos organismos (tratamento Recrutamento), enquanto três outros transectos foram monitorados sem manipulação (tratamento Monitoramento). A porcentagem de cobertura dos organismos foi avaliada pelo método de interseção. A composição específica e a abundância relativa dos organismos foram avaliadas mensalmente entre Setembro e Dezembro de 2000. Um total de 26 espécies foi encontrado na Urca, enquanto 13 foram encontradas no Catalão. Após quatro meses, a composição específica observada no recrutamento na Urca foi muito similar (76%) a observada no monitoramento. No Catalão, três meses de estudo foram suficientes para alcançar 70% de similaridade, aumentando para 80% no quarto mês. A porcentagem de cobertura dos organismos mais abundantes na Urca, não foi similar entre os transectos do monitoramento e do recrutamento, após os quatro meses do estudo (< 40%), enquanto que no Catalão, a similaridade foi de 72% já no segundo mês. A comunidade encontrada na área com alto grau de poluição orgânica (Catalão) recuperou mais rapidamente do que a comunidade da área com moderada poluição orgânica (Urca). A maior velocidade de desenvolvimento e recuperação da comunidade bentônica da área com alta poluição orgânica em relação à área menos poluída, pode estar relacionada, principalmente, à existência de comunidades mais simples e resilientes na área mais degradada

17.
Braz. arch. biol. technol ; 43(4)2000. ilus, tab, graf
Article in English | LILACS | ID: lil-458252

ABSTRACT

Teredinids survival in low salinities was determined in aquaria. Panels previously immersed in Ponta de Leste, Ilha Grande Bay, Rio de Janeiro, were transferred to aquaria with salinities ranging from 5.0 to 15.0 Practical Salinity Unities (PSU). The waters of Ilha Grande Bay receive a large amount of wood from the marginal rainforest vegetation, being suitable for the development of teredinids. The coastal areas of the bay are subjected to wide salinity fluctuations due to strong and sudden tropical storms. Eleven different species of teredinids were found in the panels. The critical salinity concentration for the survival of the two most common species was 11.93 PSU for Lyrodus floridanus and 12.90 PSU for Teredo furcifera. The effect of time on the mortality of teredinids at low salinities is also discussed.


A sobrevivência de moluscos bivalves perfurantes de madeira da família Teredinidae foi avaliada a partir de sua manutenção em aquários de baixa salinidade. Painéis de madeira previamente imersos em Ponta de Leste, Baía da Ilha Grande, RJ, foram transferidos para aquários, contendo água do mar, cujas concentrações salinas variaram de 5,0 a 15,0 PSU. A Baía da Ilha Grande recebe uma grande quantidade de madeira da vegetação marginal de Mata Atlântica, o que torna o ambiente particularmente favorável ao desenvolvimento de teredinídeos. As áreas costeiras da baía estão sujeitas a grandes variações salinas decorrentes de tempestades tropicais que ocorrem súbita e intensamente. A salinidade crítica à sobrevivência das duas espécies mais comuns nos painéis foi de 11,93, para Lyrodus floridanus e 12,90 para Teredo furcifera. O efeito do tempo na mortalidade dos teredinídeos, quando sujeitos a baixas salinidades, foi discutido.

18.
Mem. Inst. Oswaldo Cruz ; 84(supl.4): 275-280, 1989. mapas, tab, ilus
Article in Portuguese | LILACS | ID: lil-623879

ABSTRACT

In order to evaluate the diversity and infestation level of Teredinidae wood-boring molluscs, ten satations were chosen along the coast of Rio de Janeiro State. Using five pine-wood panels in each station, it was possible to distinguish five areas according to species dominance. Ilha Grande Bay is characterized by the dominance of Lyrodus floridanus (Bartsch, 1922); Sepetiba Bay, by Bankia fimbriatula Moll & Roch, 1931, Tijuca Lagoon by Teredo navalis Linnaeus, 1758; Guanabara Bay by Notoredo knoxi (Bartsch, 1917) and Araruama Lagoon by Teredo furcifera Martens, 1894. Specific composition and dominance of these species were due mainly to abiotic factors such as salinity whereas infestation level was associated not only to salinity but also to other factors such as the quantity and quality of fouling, the presence of larval dispersion focus and the wood supply in each area.


Subject(s)
Animals , Mollusca/anatomy & histology , Mollusca/growth & development , Mollusca/physiology , Turpentine , Coastal Lagoon/analysis , Bays/analysis
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