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Kriging relies on the assumption that the study area is within an infinite domain. In practice, Kriging is performed in a finite domain, generally defined by geology, and a string of samples along a drillhole is commonly truncated inside this domain. In the Kriging system, the string-end samples receive more weight as they are less screened. This feature is referred to as the ‘String Effect’ and becomes a concern in non-stationary domains in which the end and central samples are systematically different, such as (i) domains with grade enrichment or diminution towards the centre, or (ii) end samples are partially contaminated with material from adjacent domains due to sampling methods. Three methods available in the literature and one novel approach (Kriging with Adjusted Declustering [KAD]) are applied to continuous and categorical variables in three case studies. The KAD results in a significant improvement in the results of all case study models.

ABSTRACTKriging relies on the assumption that the study area is within an infinite domain. In practice, Kriging is performed in a finite domain, generally defined by geology, and a string of samples along a drillhole is commonly truncated inside this domain. In the Kriging system, the string-end samples receive more weight as they are less screened. This feature is referred to as the ‘String Effect’ and becomes a concern in non-stationary domains in which the end and central samples are systematically different, such as (i) domains with grade enrichment or diminution towards the centre, or (ii) end samples are partially contaminated with material from adjacent domains due to sampling methods. Three methods available in the literature and one novel approach (Kriging with Adjusted Declustering [KAD]) are applied to continuous and categorical variables in three case studies. The KAD results in a significant improvement in the results of all case study models.

Este estudo objetivou analisar a distribuição geográfica, evolução e produção científica dos grupos de pesquisa (GP) em treinamento de força no Brasil. Trata‐se de um estudo descritivo, de análise documental, feito na base de dados do Diretório dos GP do Brasil do CNPq. Foi feita análise das produções cientificas dos líderes dos GP entre 2014 a 2018. Foram localizados 41 GP. A maioria dos GP está localizada no Estado de São Paulo. As publicações se concentram no estrato A1 e com uma expressiva tendência nos estratos de maior qualidade ao longo dos anos. A maioria dos estudos investigou praticantes de musculação, seguido por idosos. Observa‐se que os GP brasileiros sobre treinamento de força apresentam produção científica de qualidade.

The flutter phenomenon must be carefully evaluated, as it can lead structures to collapse. This study presents a methodology based on computational fluid dynamics to obtain the flutter derivatives and the critical flutter velocity, through forced vibrations in bodies immersed in a fluid medium. Two approaches were analyzed. In the first (8COEF), torsion and flexural movements were imposed. In the second, simulations were carried out in torsion mode, and through linear equations (LE), the complete set of eight coefficients was obtained. While the first can be seen as the most robust, as all coefficients are obtained from computer simulations, the second is less computationally expensive. The study was applied to a 1:4.9 rectangle and to the cross-section of the Great Belt East Bridge (GBEB). The simulations were submitted to turbulent flow with Reynolds number equal to 105, using k–ωSST and k–ωSSTLM turbulence models. For the static case, simulations were performed to obtain the average values of the aerodynamic coefficients. OpenFOAM®was used to solve the Navier–Stokes equations for an incompressible fluid. The critical flutter velocity for the GBEB was estimated using the 8COEF and the LE approaches. It was noticed that the results estimated with the LE were effective and with a good approximation with those of the 8COEF but at a lower computational cost. All results were validated with numerical and experimental studies available in the literature. Finally, this research stands out in presenting an assertive and pragmatic CFD methodology to obtain critical flutter velocity on structures.

The aim of this study was to manufacture and characterize bionanocomposites based on a poly(hydroxybutyrate)/polyethylene glycol blend (PHB/PEG) filled with an organobentonite (CLT1 and CLT3) or an organovermiculite (VMT1 and VMT3) in concentrations of 1 and 3wt%. The systems were prepared by solution intercalation and further characterized by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. The use of these bionanocomposites aimed at improving the processing and compatibility of this blend in search of new properties and possible applications of these films in food disposable packaging. The thermal stability of the system varied according to the type of clay and, consequently, the chemical structure of the quaternary ammonium salt used. The VMT1, VMT3 and CLT3 systems showed increased degrees of crystallinity compared to neat PHB. Differences in bionanocomposites structure can be related to the type of clay used as two types of PHB/PEG blend.

AbstractThe history of science is an important component to acquire for achieving scientific literacy. In this study, a collaborative activity was applied in which the students were presented with the historical context in which Robert Hooke lived and developed the first register of the microscopic world. Furthermore, the students explored the environment using a microscope made by themselves, employing PET bottles and lenses obtained from CD or DVD readers and, finally, they drew and described selected objects, and collaboratively rewrote a ‘new version’ of Hooke’s classical book ‘Micrographia’. The study was performed in a secondary school, with 12- to 15-year-old students, and the hypothesis was that the planned intervention could enlarge students’ perception of historical aspects of the scientific discovery of the microscopic world, to a greater extent than traditional classes involving lectures and textbooks. The comparison was evaluated using a quantitative tool, called the History-Word-Association test (HWAT), which aims to evaluate the general vision of students regarding the agents, historical period and sociocultural circumstance involved in the issue addressed. The students that participated in the planned didactic activity showed a significant improvement in identification and retention of ideas associated with the history of the discovery of the microscopic world.

Objetivo: Evaluar las variables operatorias y de complicaciones en pacientes llevados a resección transuretral de próstata bipolar en un hospital universitario.

The article cites the pathophysiological features of vascular liver disorders such as transient hepatic attenuation difference (THAD), Budd-Chiari Syndrome (BCS), hepatic congestion and infarction. Transient hepatic attenuation differences may be seen as wedge-shaped areas in dynamic magnetic resonance imaging (MRI), while hepatic infarctions often manifest as perfusion defects. High contrast images of acute BCS show a flip-flop pattern in the portal venous phase, while benign regenerative nodules are evident in MRI scans of chronic BCS.