Soil apparent electrical conductivity and geographically weighted regression for mapping soil

To resolve the spatial variation in soil properties intensively is expensive, but such knowledge is essential to manage the soil better and to achieve greater economic and environmental benefits. The objective of this study was to determine whether the soil apparent electrical conductivity (ECa), alone or combined with other variables, is a useful alternative for providing detailed information on the soil in the Extremadura region of Spain. Apparent soil electrical conductivity was measured and geographically weighted regression was used to characterize the spatial variation in soil properties, which in turn can be used for soil management. This study shows that soil cation exchange capacity, calcium content, clay percentage and pH have a relatively strong spatial correlation with ECa in the soil of the study area

Análise fitoquímica do extrato etanólico do caule de Solanum crinitum LAM.

Este trabalho teve como objetivo isolar e caracterizar substâncias presentes no caule de S. crinitum utilizando cromatografia de camada fina

Stability of coordination polymers in water: state of the art and towards a methodology for nonporous materials

A mini review on the study concerning water stability of coordination polymers (CPs) is presented. Next, following the procedure proposed recently by Gelfand and Shimizu (Dalton Trans 45:3668-3678, 2016) the stability of three cysteine (Cys)containing CPs is investigated. The stability of studied CPs decreases in the order: Zn(Cys)(2)>Mg(Cys)(2)>Ca(Cys)(2) H2O. For the latternever reported before, the structure is additionally determined and it is proved that water is located in the first coordination sphere. It is shown that for nonporous CPs, in contrast to the porous ones, the immersion in water at 20 degrees C is more drastic for studied solids than the harsh humid conditions (80 degrees C at 90% R.H.). Finally all materials are assigned to the hydrolytic stability groups and it is concluded that the stability of studied CPs correlates well with the standard reduction potentials. This leads to the conclusion that the application of more inert metal as a node causes larger stability of studied CPs

On the manufacturing of highly-customized near net-shape medical implants using magnesium alloy sheet

Incluída en Procedia Manufacturing 50The purpose of this work is defining a global methodology framework for the manufacturing of medical implants using Mg alloys by Incremental Forming process from the results attained by the authors in this field. The methodology proposed considers two main steps, an indispensable related to material characterization that includes from the classical and mechanical to spifability testing and it includes numerical simulations. And another one related mainly to implant forming taking into account the best process parameters from the analysis carried out in the previous step. As newness, two variants of the incremental forming process, Single (SPIF) and Two-Point (TPIF) Incremental Forming, are used for the same magnesium implant geometry. Different outputs variables, mainly: Ra, Shape accuracy and Thicknesses, besides Force and Temperature were analysed for comparison purposes.Universidad de Girona MPCUdG2016 / 036Ministerio de Educación, Universidad e Investigación (Italia) CUP - D94I18000260001Ministerio de Educación (España) DPI2016-77156-

Análise fitoquímica do extrato etanólico do caule de Solanum rugosum Dunal.

Este trabalho teve como objetivo isolar e caracterizar substâncias presentes no caule de S. rugosum utilizando cromatografia de camada fina

Overhydration prevalence in peritoneal dialysis - A 2 year longitudinal analysis

Hypervolemia is a major concern in dialysis patients, and is associated with increased cardiovascular risk and death. Cross sectional analysis have previously demonstrated that peritoneal dialysis (PD) patients are not more overhydrated when compared to haemodialysiś ones. This study was designed to evaluate longitudinal trends in hydration status and corporal composition in a PD population.Pedro Ventura Aguiar, by Abbott laboratory for conferences presentation

Efeito do cálcio sobre as características anatômicas de raízes de milho (Zea mays L.) "Saracura" BRS-4154 submetido ao alagamento em casa de vegetação.

O milho "Saracura" BRS-4154 apresenta-se como uma opção válida para as várzeas sujeitas ao alagamento temporário. Pesquisas têm demonstrado que a presença de CaCl2 no ambiente de germinação alagado aumenta a tolerância do milho "Saracura" a essa condição. Este trabalho foi conduzido em casa de vegetação na Embrapa Milho e Sorgo, localizada no município de Sete Lagoas -MG, com o objetivo de obter melhor conhecimento das alterações anatômicas em Milho "Saracura" BRS-4154 sob efeito de cálcio e alagamento. As plantas foram submetidas aos tratamentos com e sem adição de uma dose de 300 kg. ha-1 de cloreto de cálcio, incorporado em todo o solo. Cada tratamento foi avaliado em condições normais de irrigação e sob encharcamento imposto a partir do estádio V6 até a floração. O tratamento controle foi com irrigação normal e sem aplicação de cálcio. As avaliações do ensaio foram realizadas na floração. Foram retirados fragmentos de raízes de 5 cm de comprimento, os quais foram submetidos a técnicas clássicas em microtécnica vegetal para confecção e análise de tecidos. Foram observadas diferenças anatômicas entre os tratamentos alagado e com irrigação normal. O alagamento induziu, em raízes, aumento de espaços intercelulares, aumento da espessura do córtex e do cilindro vascular. Em relação à espessura da epiderme, esta foi mais espessa em condições normais. A presença de aerênquimas ocorreu somente em plantas em condições alagadas, comprovando que esses não são constitutivos desta espécie. A proporção de aerênquimas diminuiu com a aplicação de cálcio, mostrando a participação desse íon em manter a integridade da parede celular, evitando o colapso desordenado e aumentando a sobrevivência da planta em condições alagadas. A aplicação de cálcio influenciou no arranjo celular da epiderme e promoveu um menor espessamento da exoderme em condições normais de irrigação

The role of counter-ions in crystal morphology, surface structure and photocatalytic activity of ZnO crystals grown onto a substrate

In this contribution, we present an experimental and theoretical investigation of the role of counter-ions in the crystal morphology, surface structure, and photocatalytic activity of hierarchical ZnO nanostructures. The effect of zinc precursor (nitrate, acetate and, sulfate) along the synthesis of ZnO nanostructures grown directly onto a substrate by means of a simple hydrothermal method was analyzed in detail. Scanning electron microscopy images showed a preferential growth of ZnO nanostructures along the c-axis, with a slight reduction in the orientation depending on the choice of the Zn source. Theoretical calculations based on the Wulff theory allowed us to better understand the morphological changes and directly relate the photocatalytic performance at the different exposed surfaces of the as-observed crystal shapes. Our results showed that photocatalytic activities in the discoloration of organic dyes became superior for hierarchical ZnO nanostructures obtained from zinc nitrate. This finding was explained by X-ray photoelectron and photoluminescence spectroscopies, which revealed that in addition to, the attached counter-ions and the abundance of carboxylate groups and organic residuals on ZnO surfaces, the presence of surface defects are determinant to enhance the photocatalytic performance of the material

Computational procedure to an accurate DFT simulation to solid state systems

The density functional theory has become increasingly common as a methodology to explain the properties of crystalline materials because of the improvement in computational infrastructure and software development to perform such computational simulations. Although several studies have shown that the characteristics of certain classes of materials can be represented with great precision, it is still necessary to improve the methods and strategies in order to achieve more realistic computational modeling. In the present work, strategies are reported in a systematic way for the accurate representation of crystalline systems. The crystalline compound chosen for the study as a case test was BaMoO4, both because of its potential technological application and because of the low accuracy of the simulations previously reported in the literature. The computational models were carried out with the B3LYP and WC1LYP functionals selected from an initial set containing eight hybrid functionals in conjunction with an all-electron basis set. Two different strategies were applied for improving the description of the initial models, both involving atomic basis set optimization and Hartree-Fock exchange percentage adjustment. The results obtained with the two strategies show a precision of structural parameters, band gap energy, and vibrational properties never before presented in theoretical studies of BaMoO4. Finally, a flowchart of good calculation practices is elaborated. This can be of great value for the organization and conduction of calculations in new research

Selective disruption of Tcf7l2 in the pancreatic β cell impairs secretory function and lowers β cell mass

Type 2 diabetes (T2D) is characterized by β cell dysfunction and loss. Single nucleotide polymorphisms in the T-cell factor 7-like 2 (TCF7L2) gene, associated with T2D by genome-wide association studies, lead to impaired β cell function. While deletion of the homologous murine Tcf7l2 gene throughout the developing pancreas leads to impaired glucose tolerance, deletion in the β cell in adult mice reportedly has more modest effects. To inactivate Tcf7l2 highly selectively in β cells from the earliest expression of the Ins1 gene (∼E11.5) we have therefore used a Cre recombinase introduced at the Ins1 locus. Tcfl2fl/fl::Ins1Cre mice display impaired oral and intraperitoneal glucose tolerance by 8 and 16 weeks, respectively, and defective responses to the GLP-1 analogue liraglutide at 8 weeks. Tcfl2fl/fl::Ins1Cre islets displayed defective glucose- and GLP-1-stimulated insulin secretion and the expression of both the Ins2 (∼20%) and Glp1r (∼40%) genes were significantly reduced. Glucose- and GLP-1-induced intracellular free Ca2+ increases, and connectivity between individual β cells, were both lowered by Tcf7l2 deletion in islets from mice maintained on a high (60%) fat diet. Finally, analysis by optical projection tomography revealed ∼30% decrease in β cell mass in pancreata from Tcfl2fl/fl::Ins1Cre mice. These data demonstrate that Tcf7l2 plays a cell autonomous role in the control of β cell function and mass, serving as an important regulator of gene expression and islet cell coordination. The possible relevance of these findings for the action of TCF7L2 polymorphisms associated with Type 2 diabetes in man is discusse