Deflections in beams of Argentinean Eucalyptus grandis under long-term loading

The present paper reports the results of an investigation regarding the analysis of deflections in structural-sized beams of fast-growth Argentinean Eucalyptus grandis under a one-year loading and in indoor climate. An empirical research project with a sample containing 16 beams was carried out. 8 pieces were free of pith and another 8 pieces contained pith. The results obtained allow to compare the creep behaviour of this timber species with those reported by other researchers for both structural-sized and small-clear specimens. The research confirms the design rules adopted by Eurocode 5 for calculating the creep deflections of this timber species under a long-term load. Results also evidence a slight influence of the presence of pith on creep, confirming similar creep behaviour for different qualities of this timber species

Variación radial y axial del hinchamiento, del factor anisotrópico y de la densidad, en el Eucalyptus grandis de Argentina.

En este trabajo se presentan los resultados de una investigación orientada a estudiar la variación de los hinchamientos tangencial y radial, así como del coeficiente de anisotropía y la densidad anhidra, en función de la altura y la distancia a la médula de árboles de Eucalyptus grandis cultivados en la Mesopotamia de Argentina. Con este propósito se diseñó y llevó a cabo una investigación empírica con muestras seleccionadas al azar. Los resultados muestran que, para propósitos prácticos, puede asumirse que el hinchamiento y el coeficiente de anisotropía tienen una tendencia decreciente al aumentar la altura, y creciente al aumentar la distancia a la médula. La madera de la periferia exhibe un comportamiento más desfavorable desde el punto de vista de los movimientos dimensionales que la del interior del tronco, si bien presenta mayor densidad y consecuentemente mejor calidad para numerosos empleos.The present paper reports the results of an investigation regarding the variation in swelling, coefficient of anisotropy and density, as a function of the distance from the pith and the height, in trees of Argentinean Eucalyptus grandis. For this purpose an empirical research project with samples randomly selected was designed and carried out. According to the results and for practical purposes, it may be assumed that swelling and the coefficient of anisotropy decrease with height and increase with the distance from the pith. Wood of the outer part of the tree stem exhibits more problems related to dimensional changes than wood of the inner part of the tree stem, even though it presents higher density and, consequently, higher quality for many purposes

Creep in structural-sized beams of argentinean Eucalyptus Grandis

The results presented in this paper were obtained from a test carried out during the last series of a research project regarding the creep behaviour of Argentinean Eucalyptus grandis loaded in dry condition. A test with a sample containing 15 structural-sized beams was carried out during 470 days. 7 pieces were free of pith and another 8 contained it. The results allow to compare the creep behaviour of these beams with previous data reported for both structural-sized and small-clear specimens of this timber species and also with those reported for other species. The effectiveness of the criteria adopted by overseas standards as well as those of Latin-American countries for calculating the creep deflections of this timber species under a long-term loading is analysed. The creep deflections obtained in the present research are higher than those calculated by means of the procedures of the Brazilian standard NBR 7190, the European standard Eurocode 5, the American standard National Design Specification for Wood Construction and the Peruvian standard. On the contrary, creep results obtained in this test are lower than those calculated according to the New Zealand standard NZS 3603, the Chilean standard NCh 1198 and the former German standard DIN 1052

Maternal effects in a wild songbird are environmentally plastic but only marginally alter the rate of adaptation

Despite ample evidence for the presence of maternal effects (MEs) in a variety of traits and strong theoretical indications for their evolutionary consequences, empirical evidence to what extent MEs can influence evolutionary responses to selection remains ambiguous. We tested the degree to which MEs can alter the rate of adaptation of a key life-history trait, clutch size, using an individual-based model approach parameterized with experimental data from a long-term study of great tits (Parus major). We modeled two types of MEs: (i) an environmentally plastic ME, in which the relationship between maternal and offspring clutch size depended on the maternal environment via offspring condition, and (ii) a fixed ME, in which this relationship was constant. Although both types of ME affected the rate of adaptation following an abrupt environmental shift, the overall effects were small. We conclude that evolutionary consequences of MEs are modest at best in our study system, at least for the trait and the particular type of ME we considered here. A closer link between theoretical and empirical work on MEs would hence be useful to obtain accurate predictions about the evolutionary consequences of MEs more generally

Cosmic-ray searches with the MATHUSLA detector

The performance of the proposed MATHUSLA detector as an instrument for studying the physics of cosmic rays by measuring extensive air showers is presented. The MATHUSLA detector is designed to observe and study the decay of long-lived particles produced at the pp interaction point of the CMS detector at CERN during the HL-LHC data-taking period. The proposed MATHUSLA detector will be composed of many layers of long scintillating bars that cannot measure more than one hit per bar and correctly report the hit coordinate in case of multiple hits. This study shows that adding a layer of RPC detectors with both analogue and digital readout significantly enhances the capabilities of MATHUSLA to measure the local densities and arrival times of charged particles at the front of air showers. We discuss open issues in cosmic-ray physics that the proposed MATHUSLA detector with an additional layer of RPC detectors could address and conclude by comparing with other air-shower facilities that measure cosmic rays in the PeV energy range.Comment: 64 pages, 58 figure

Exploring cloud-based platforms for rapid insar time series analysis

The idea of near real-time deformation analysis using Synthetic Aperture Radar (SAR) data as a response to natural and anthropogenic disasters has been an interesting topic in the last years. A major limiting factor for this purpose has been the non-availability of both spatially and temporally homogeneous SAR datasets. This has now been resolved thanks to the SAR data provided by the Sentinel-1A/B missions, freely available at a global scale via the Copernicus program of the European Space Agency (ESA). Efficient InSAR analysis in the era of Sentinel demands working with cloud-based platforms to tackle problems posed by large volumes of data. In this study, we explore a variety of existing cloud-based platforms for Multioral Interferometric SAR (MTI) analysis and discuss their opportunities and limitations

Insulin-like growth factor binding protein 5 enhances survival of LX2 human hepatic stellate cells

ABSTRACT: BACKGROUND: Expression of insulin-like growth factor binding protein 5 (IGFBP5) is strongly induced upon activation of hepatic stellate cells and their transdifferentiation into myofibroblasts in vitro. This was confirmed in vivo in an animal model of liver fibrosis. Since IGFBP5 has been shown to promote fibrosis in other tissues, the aim of this study was to investigate its role in the progression of liver fibrosis. METHODS: The effect of IGFBP5 was studied in LX2 cells, a model for partially activated hepatic stellate cells, and in human primary liver myofibroblasts. IGFBP5 signalling was modulated by the addition of recombinant protein, by lentiviral overexpression, and by siRNA mediated silencing. Furthermore, the addition of IGF1 and silencing of the IGF1R was used to investigate the role of the IGF-axis in IGFBP5 mediated effects. RESULTS: IGFBP5 enhanced the survival of LX2 cells and myofibroblasts via a >50% suppression of apoptosis. This effect of IGFBP5 was not modulated by the addition of IGF1, nor by silencing of the IGF1R. Additionally, IGFBP5 was able to enhance the expression of established pro-fibrotic markers, such as collagen Ialpha1, TIMP1 and MMP1. CONCLUSION: IGFBP5 enhances the survival of (partially) activated hepatic stellate cells and myofibroblasts by lowering apoptosis via an IGF1-independent mechanism, and enhances the expression of profibrotic genes. Its lowered expression may, therefore, reduce the progression of liver fibrosi

Catálogo Taxonômico da Fauna do Brasil: setting the baseline knowledge on the animal diversity in Brazil

The limited temporal completeness and taxonomic accuracy of species lists, made available in a traditional manner in scientific publications, has always represented a problem. These lists are invariably limited to a few taxonomic groups and do not represent up-to-date knowledge of all species and classifications. In this context, the Brazilian megadiverse fauna is no exception, and the Catálogo Taxonômico da Fauna do Brasil (CTFB) (http://fauna.jbrj.gov.br/), made public in 2015, represents a database on biodiversity anchored on a list of valid and expertly recognized scientific names of animals in Brazil. The CTFB is updated in near real time by a team of more than 800 specialists. By January 1, 2024, the CTFB compiled 133,691 nominal species, with 125,138 that were considered valid. Most of the valid species were arthropods (82.3%, with more than 102,000 species) and chordates (7.69%, with over 11,000 species). These taxa were followed by a cluster composed of Mollusca (3,567 species), Platyhelminthes (2,292 species), Annelida (1,833 species), and Nematoda (1,447 species). All remaining groups had less than 1,000 species reported in Brazil, with Cnidaria (831 species), Porifera (628 species), Rotifera (606 species), and Bryozoa (520 species) representing those with more than 500 species. Analysis of the CTFB database can facilitate and direct efforts towards the discovery of new species in Brazil, but it is also fundamental in providing the best available list of valid nominal species to users, including those in science, health, conservation efforts, and any initiative involving animals. The importance of the CTFB is evidenced by the elevated number of citations in the scientific literature in diverse areas of biology, law, anthropology, education, forensic science, and veterinary science, among others