Cosmic rays 10Be biennal data and their relationship to aurorae and sunspots

The galactic cosmic ray (C.R.) variations which should give information on three dimensional aspects of the heliospheric magnetic fields and on the solar wind, which modulate their influx into the Solar System were studied. In order to decode the information from the C.R. series it is necessary to know the mechanisms through which the modulation is produced. It it clear that a balance of effects with sources at different heliospheric latitudes results in the modulated C.R. intensity. It is found that the modulation of 10Be in polar ice may be due to at least two main contributions: (1) negative and in phase with the Solar flare activity modulating the cosmic ray flux in Forbush-type decreases, and (2) positive in phase with the appearance of large wind streams situated at both polar coronal holes. It is found that the high heliolatitude activity is related to a stable periodicity of 11.1y whereas the low heliolatitude activity contributes to the wondering of the solar cycles

Geometrical size effect in high cycle fatigue strength of heavy-walled Ductile Cast Iron GJS400: Weakest link vs. defect-based approach

Fatigue strength is known to decrease with increasing dimension of the component. This is due to a technological size effect, related to the production process, and to a geometrical size effect, due to a higher probability of finding a large defect. To investigate the latter, an heavy-walled component made of Ductile Cast Iron (DCI) has been trepanned and a fatigue test plan has been carried out using 4 different specimen geometries. An attempt has been made to relate the resulting fatigue strength using a weakest-link approach based on the effective volumes and surfaces. This approach seems to work well only in cases of different specimen's lengths. Some of the fracture surfaces were analyzed by means of SEM and the initiating defects were identified and measured. An approach in which the defects population can be randomly distributed in the specimen has been tried. Virtual fatigue tests have been carried out by considering pure propagation of the worst defect. The resulting fatigue curves showed that this approach is promising but needs further description of the initiation phase

Cosmic ray secular variations in terrestrial records and aurorae

The rediscovery that the Sun and the solar wind can undergo important changes on historical time scales has brought into question the stability of the cyclic behavior of past time series of solar and solar-terrestrial origin. It was found by Vector Fourier analysis that the solar 11 year cycle is present in the series of 10Be, delta 180, in ice cores and of thermoluminescence (TL) in sea sediments during the last Millennia with a frequency modulation, related to the Sun behavior, as tested by comparison with the Sunspot number R sub z series. It was shown that the cyclogram of the series of yearly Aurorae from 1721 to 1979 linear-regression-corrected-for-R sub z is straight for the periodicity zeta=11,1y, which indicates that such periodicity is constant in time corresponding to the only line present in the 11y band. The maxima of this component appear at the same time together with the high speed solar wind streams taking place in coronal holes situated in high heliolatitudes. It is evidenced that the 11 year cycle has undergone frequency oscillations on a time scale of two centuries, although it is very difficult to determine the periodicities with high accuracy

Integration of gis technology, remote sensing and multivariate analysis in the delimitation of physiographic units for pedological mapping

Este trabalho foi conduzido com o propósito de estabelecer-se um levantamento pedológico semidetalhado no Município de Ivatuba-PR, usando a associação entre técnicas e equipamentos que pudessem levar a delimitação de unidades físiográfícas cujos limites e subdivisões não se restringissem apenas ao critério do foto intérprete. Para tanto, foi avaliada uma matriz de dados obtida através do cruzamento, por meio de um Sistema de Informações Geográficas (SIG), entre uma grade regular com células de 300 x 300 metros e um mapa base de drenagem da área de estudos, bandas 3, 4, 5 e 7 do TM-LANDSAT e um mapa de declividades da área gerado em SIG. As variáveis coletadas dentro de cada célula da grade regular foram: canais longo, médio e curto das ordens 1ª à 7ª, declividade ponderada e o nível de cinza das bandas, resultando na produção de uma matriz com 1167 indivíduos com vinte e sete variáveis, cujos dados foram expostos à analise de agrupamentos. A análise propiciou a produção de dendrogramas que foram analisados, permitindo a representação pelas células da grade regular, com a finalidade de criação de pictogramas em que a separação de grupos de indivíduos servissem de "guias" que, sobrepostos às imagens orbitais HRV-SPOT devidamente tratadas e manipuladas, pudessem orientar a discriminação de unidades fisiográfícas através da interpretação destas sobre o monitor colorido do sistema SITIM. Foram delimitados 62 polígonos que configuraram a presença de nove unidades fisiográficas que geraram um mapa de solos semidetalhado do município. Em relação à possibilidade de mapeamento das unidades fisiográficas sobre o monitor colorido, os resultados apresentados demonstraram que, através da utilização dos guias, tais unidades podem ser delimitadas com grande redução da subjetividade do foto intérprete. Os polígonos semelhantes, delimitados pela metodologia utilizada, apresentaram solos homogêneos dentro de sua classe taxonómica. Já os polígonos diferentes apresentaram solos com características diferenciadoras entre si.This study was based on an association of techniques and equipment that could lead to the delimitation of physiographic units not merely restricted to the photointerpreter's criteria. A data matrix was evaluated which was obtained from the crossing, by means of Geographic Information System (GIS), of a regular grid with cells 300 x 300 meters and a drainage base map of the study area and bands 3, 4, 5 and 7 from TM-LANDSAT and a slope map generated in a GIS. The variables collected in each cell of the regular grid were: long, medium and short channels from the first to the seventh order, weighted slope and the grey levels (DNs) in bands, resulting in a matrix with 1167 individuals with 27 variables, whose data were subjected to cluster analysis. This analysis provided dendrograms which enabled the separation of groups of individuals represented by cells from the regular grid, aiming at creating pictograms to serve as "guides". These guides overlaid upon properly treated and handled orbital HRV-SPOT images oriented the discrimination of physiographic units on the color monitor of the image processing system. Among the variables used, those referring to drainage network were best for cluster analysis of regular grid cells. The variables relief and grey levels of TM-LANDSAT image also presented satisfactory results with the methodology applied

The aberrant expression in epithelial cells of the mesenchymal isoform of FGFR2 controls the negative crosstalk between EMT and autophagy

Signalling of the epithelial splicing variant of fibroblast growth factor receptor 2 (FGFR2b) triggers both differentiation and autophagy, while the aberrant expression of the mesenchymal FGFR2c isoform in epithelial cells induces impaired differentiation, inhibition of autophagy as well as the induction of the epithelial-mesenchymal transition (EMT). In light of the widely proposed negative loop linking autophagy and EMT in the early steps of carcinogenesis, here we investigated the possible involvement of FGFR2c aberrant expression and signalling in orchestrating this crosstalk in human keratinocytes. Biochemical, molecular, quantitative immunofluorescence analysis and in vitro invasion assays, coupled to the use of specific substrate inhibitors and transient or stable silencing approaches, showed that AKT/MTOR and PKCε are the two hub signalling pathways, downstream FGFR2c, intersecting with each other in the control of both the inhibition of autophagy and the induction of EMT and invasive behaviour. These results indicate that the expression of FGFR2c, possibly resulting from FGFR2 isoform switch, could represent a key upstream event responsible for the establishment of a negative interplay between autophagy and EMT, which contributes to the assessment of a pathological oncogenic profile in epithelial cells

Recent results and new hardware developments for protein crystal growth in microactivity

Protein crystal growth experiments have been performed on 16 space shuttle missions since April, 1985. The initial experiments utilized vapor diffusion crystallization techniques similar to those used in laboratories for earth-based experiments. More recent experiments have utilized temperature induced crystallization as an alternative method for growing high quality protein crystals in microgravity. Results from both vapor diffusion and temperature induced crystallization experiments indicate that proteins grown in microgravity may be larger, display more uniform morphologies, and yield diffraction data to significantly higher resolutions than the best crystals of these proteins grown on earth

A Robust Implicit Optimal Order Formula for Direct Integration of Second Order Orbital Problems

In this paper, a robust implicit formula of optimal order for direct integration of general second order orbital problems of ordinary differential equations (ODEs) is proposed. This method is considered capable avoiding the computational burden and wastage in computer time in connection with the method of reduction to first order systems. The integration algorithms and analysis of the basic properties are based on the adoption of Taylor’s expansion and Dahlquist stability model test. The resultant integration formula is of order ten and it is zero-stable, consistent, convergent and symmetric. The numerical implementation of the method to orbital and two-body problems demonstrates increased accuracy with the same computational effort on comparison with similar second order formulas. Keywords: Optimal-order, Zero-stability, Convergence, Consistent, IVPs, Predictor-corrector, Error constant, Symmetric