2,345 research outputs found
Brachiaria As A Cover Crop To Improve Phosphorus Use Efficiency In A No-till Oxisol
Oxidic soils are phosphorus drains in soil; hence, P availability is a limiting factor in tropical, weathered Oxidic soils. It has been shown that some brachiarias grown as cover crops may increase soil available P to subsequent crops. The objective of this study was to evaluate soil P cycling and availability, as well as the response of soybean to soluble and natural reactive phosphates as affected by ruzi grass (Urochloa ruziziensis, R. Germ. and C.M. Evrard, Crin) grown as a cover crop in a no-till system. Experimental treatments consisted of the presence or absence of ruzi grass in combination with a control (0.0 P) and soluble and reactive rock phosphate broadcast on the soil surface in the winter (80 kg ha-1 P2O2), plus three rates of P applied to soybean furrows (0, 30, and 60 kg ha-1 of P2O5) at planting, in the form of triple superphosphate. Soybean was cropped in two seasons: 2010/2011 and 2011/2012. Soil samples were taken before soybean planting (after desiccation of Brachiaria) at 0.00-0.05 and 0.05-0.10 m for soil available P. Total weight of dry matter and P accumulated in ruzi grass were determined, as well as soybean yields, P in soybean grains, and P use efficiency (PUE). The use of natural phosphate increased soil P availability. The highest yields were obtained with higher application rates of triple superphosphate in the planting furrow combined with broadcast rock phosphate. Broadcast application of Arad reactive phosphate increases and maintains soil available P, and this practice, associated with ruzi grass grown as a cover crop and the use of triple superphosphate applied to soybean furrows, results in higher use of P by soybeans. © 2016, Revista Brasileira de Ciencia do Solo. All rights reserved.4
The 7th Italian-brazilian Meeting In Hematology [7° Encontro Da Associação Ítalo-brasileira De Hematologia]
[No abstract available]30SUPPL. 21
Environmental Services Associated With The Reclamation Of Areas Degraded By Mining: Potential For Payments For Environmental Services
This paper discusses the potential of associating environmental services (ES) with techniques for reclaiming degraded areas (RDA) used in the mining sector, considering the current trends in payments for environmental services (PES) in Brazil. A literature review with content analysis generated results which identified the ES generated for eight cases of RDA in mining. As an example, ES related to soil enhancement were found. A more extended review of general RDA techniques confirmed the potential for associating other ES to RDA techniques used in mining, an example here is the enhancement of carbon stocks. Support for actions could come from existing PES schemes, particularly for cases where the ES identified as associated with an RDA technique are related to soil and water conservation. Concluding remarks indicate that there is a potential scenario for ES diversification in the reclamation stage of mining operations. A first step towards accomplishing this diversification envisages the creation of a PES scheme specific to the mining sector. Further studies are needed to develop criteria for fostering a PES scheme specifically for the reclamation phase of mining operations in Brazil.19213716
Bound states in disclinated graphene with Coulomb impurities in the presence of a uniform magnetic field
AbstractIn this contribution, we study the effects caused by an impurity on the quantum dynamics of massive excitations in a disclinated graphene in the presence of an external magnetic field. Within a continuum approach, the problem is mathematically modeled by the definition of a special vector potential containing all the information about the topology and the interacting fields. The presence of disclination is introduced by a term in the Dirac equation that translates the appearance of a phase associated with the transport of the spinor around the apex of the cone. We solve exactly the Dirac equation for this problem and the eigenvalues are obtained. We observe the influence of the disclination on the spectrum of energy and the allowed values of magnetic field
Multihierarchical electrodes based on titanate nanotubes and zinc oxide nanorods for photoelectrochemical water splitting
Studies involving water splitting to form hydrogen and oxygen have attracted attention because H2 is considered the fuel of the future. Photoelectrocatalysts have been widely used for this application, and several metal oxides can be applied as catalysts. Among them, we highlight zinc oxide nanorods (ZnONRs) and titanate nanotubes (TiNTs); however, their individual nanostructures exhibit disadvantages. For example, ZnONR shows rapid recombination of the photogenerated charges, and TiNT gives rise to randomly orientated films; these disadvantages limit their application as photoanodes. In this study, for the first time, we present a new class of multihierarchical electrodes based on TiNT-decorated ZnONR films that exhibited superior results to the individual species. The TiNTs are homogenously dispersed over the surface of the rods without forming agglomerates, giving rise to a heterojunction that exhibits lower recombination rates. It was found that the results are better when the contents of TiNT in the electrode are higher; thus, glycine was successfully used as a bridge to link both of the structures, increasing the amount of TiNT decorating the rods. As a result, the photocurrent generated with these multihierarchical electrodes is higher than that obtained for pure ZnONR electrodes (0.9 mA and 0.45 mA, respectively), and the electrode potentials for O2 evolution is lower than that observed for pure TiNT electrodes (0 V and 0.8 V vs. ERHE, respectively). The IPCE values are also higher for the multihierarchical electrodes
DESCRIÇÃO MORFOLÓGICA E SEDIMENTAR DO RIO PARAGUAI NO SEGMENTO ENTRE O POÇO DO RENATO A BAÍA DA INHAROSA
O estudo foi realizado no rio Paraguai no trecho entre o Poço do Renato a baía Inharosa no município de Cáceres, MT. Realizou a quantificação das feições morfológicas, batimétria e análise de laboratório. Na área de estudo encontrou-se várias feições morfologicas como: lagoas, canal comaltados, canal secundários, ilhas e bancos de sedimentos. Nos sedimentos de fundo predominou areia média
Wax Chemical and Morphological Investigation of Brazilian Crude Oils
The waxes in petroleum can precipitate and form unwanted gels and deposition when exposed to low temperatures. The idea of this chapter is to approach methods of quantification and physicochemical and morphological characterization of waxes and how this information can help in understanding this deposition. Information such as the quantity of waxes and the chemical structures in the oil is fundamental to predict the possible deposition and its ability to aggregate with other crystals. For example, the knowledge about the wax morphology may contribute to explain the nucleation and growth of the deposits. The polarized light microscopy, the most common technique to visualize wax crystals, and the bright-field microscopy, the most simple technique, able to show crystal details that have not been seen on the polarized light, was used
Concomitant essential thrombocythemia with jak2 v617f mutation in a patient with chronic myeloid leukemia with major molecular response with imatinib and long-term follow-up
The association of chronic myeloid leukemia (CML) with other myeloproliferative neoplasms (MPNs), in particular with the V617F mutation in the Janus kinase 2 (JAK2) gene, is very uncommon, and there are only a few cases reported in the literature. In the present study, the case of a 73-year-old man with CML and persistent thrombocytosis, is reported. The patient achieved a complete cytogenetic response and major molecular response (MR) with imatinib. The patient presented JAK2 V617F mutation, and bone marrow morphology was consistent with essential thrombocythemia. The patient was treated with imatinib and hydroxyurea to control the platelet count, and maintains complete MR with imatinib upon 10 years of follow-up. Although rare, the association of breakpoint cluster region-Abelson rearrangement and JAK2 V617F mutation should be investigated in patients with MPN, since both genetic anomalies may be present at diagnosis or may emerge during treatment, and require different therapeutic approaches.The association of chronic myeloid leukemia (CML) with other myeloproliferative neoplasms (MPNs), in particular with the V617F mutation in the Janus kinase 2 (JAK2) gene, is very uncommon, and there are only a few cases reported in the literature. In the121485487sem informaçãosem informaçã
Tratamiento conservador del hallux valgus juvenil mediante ortesis nocturnas
Se presentan los resultados obtenidos con tratamiento conservador del hallux valgus
juvenil con el uso de ortesis nocturnas confeccionadas a medida, con material termoplástico, en 18
pacientes con edades de 8 a 15 años (media: 12 años). El tiempo medio de tratamiento fue de 18 meses
y los pacientes fueron seguidos después del tratamiento por igual período de tiempo. Debe destacarse
el alto abandono del método que alcanzó la cifra del 44%. Fueron utilizados como parámetros
de valoración de resultados las medidas radiográficas de los ángulos de valguismo del hallux
(AVH) e intermetatarsiano l-II (AIM), obtenidas antes y después de terminado el período de observación.
El valor medio inicial del AVH fue de 22° y al final fue de 20°. Las medidas de los valores
del AIM fueron 11 y 10,7°, respectivamente. Ambas medidas no se diferencian entre sí desde el punto
de vista estadístico, lo que lleva a concluir que el tratamiento utilizado no fue capaz de corregir
las deformidades básicas del hallus valgus infantil, pero evita la progresión de esas deformidades.The results of conservative treatment of adolescent hallux valgus using custom made
nocturnal splints in 18 patients ranging in age from 8 to 15 years (mean 12) are presented. The
average period of treatment and follow-up was 18 months. There was a high rate (44%) of treatment
abandon. As assessment parameters were used radiographic measures of the hallux valgus angle
and the intermetatarsal I-II angle. Measures were obtained before treatment and at the end of
follow-up. The initial mean valgus angle was 22° and the last mean value 20°. The mean valus of the
intermetatarsal angle were respectively 11° and 10,7°. There were no significant statistical differences,
indicating that the treatment of hallux valgus using nocturnal splintage do not correct the
deformity but avoid its progression
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