Validation of a dynamic modulus predictive equation on the basis of spanish asphalt concrete mixtures

Dynamic modulus is defined as the ratio of peak cyclic stress to peak cyclic strain under harmonic loading. It is one of the most important properties of asphalt mixtures, since it determines the strain response characteristics as a function of loading rate and temperature. Different simplified models exist that can predict this variable from mixture composition and binder rheological data, with Witczak and Hirsh models being the most widely accepted. These models have been evaluated in the present study, on the basis of 352 data points from eight asphalt concrete mixtures that were tested between −5 and 60 °C. A new model is also formulated which improves predictions of the previous ones for Spanish mixtures, even though it is a relatively simple equation that requires very limited binder rheological data compared to Witczak and Hirsch modelsValidación de una fórmula predictiva del módulo dinámico a partir de mezclas españolas tipo hormigón bituminoso. El módulo dinámico es la relación entre los picos de tensión y deformación bajo carga armó- nica. Es una de las propiedades más importantes de las mezclas bituminosas, ya que determina la respuesta deformacional en función de la velocidad de carga y la temperatura. Existen diferentes modelos simplificados que permiten predecir esta variable a partir de la composición de la mezcla y de las características reológicas del betún, siendo los de Witczak y el de Hirsch los más ampliamente aceptados. Dichos modelos han sido evaluados en el presente estudio a partir de 352 puntos procedentes de ocho mezclas tipo hormigón bituminoso que fueron ensayadas entre −5 y 60 °C. Así mismo, se ha formulado un nuevo modelo que mejora las predicciones de los anteriores para las mezclas españolas, aun tratándose de una ecuación relativamente simple que requiere una mínima información reológica del betún en comparación con los modelos de Witczak y Hirsch.Peer reviewe

Population expansion in the North African Late Pleistocene signalled by mitochondrial DNA haplogroup U6

Background <br/> The archaeology of North Africa remains enigmatic, with questions of population continuity versus discontinuity taking centre-stage. Debates have focused on population transitions between the bearers of the Middle Palaeolithic Aterian industry and the later Upper Palaeolithic populations of the Maghreb, as well as between the late Pleistocene and Holocene. <br/> Results Improved resolution of the mitochondrial DNA (mtDNA) haplogroup U6 phylogeny, by the screening of 39 new complete sequences, has enabled us to infer a signal of moderate population expansion using Bayesian coalescent methods. To ascertain the time for this expansion, we applied both a mutation rate accounting for purifying selection and one with an internal calibration based on four approximate archaeological dates: the settlement of the Canary Islands, the settlement of Sardinia and its internal population re-expansion, and the split between haplogroups U5 and U6 around the time of the first modern human settlement of the Near East. <br/> Conclusions <br/> A Bayesian skyline plot placed the main expansion in the time frame of the Late Pleistocene, around 20 ka, and spatial smoothing techniques suggested that the most probable geographic region for this demographic event was to the west of North Africa. A comparison with U6's European sister clade, U5, revealed a stronger population expansion at around this time in Europe. Also in contrast with U5, a weak signal of a recent population expansion in the last 5,000 years was observed in North Africa, pointing to a moderate impact of the late Neolithic on the local population size of the southern Mediterranean coast

Molecular mechanisms of zinc toxicity in the potworm Enchytraeus crypticus, analysed by high-throughput gene expression profiling

Zinc (Zn) is known to be relatively toxic to some soil-living invertebrates including the ecologically important enchytraeid worms. To reveal the molecular mechanisms of zinc toxicity we assessed the gene expression profile of Enchytraeus crypticus (Enchytraeidae), exposed to the reproduction effect concentrations EC10 and EC50, over 4 consecutive days, using a high-throughput microarray (species customized). Three main mechanisms of toxicity to Zn were observed: 1) Zn trafficking (upregulation of zinc transporters, a defence response to regulate the cellular zinc level), 2) oxidative stress (variety of defence mechanisms, triggered by Reactive Oxygen Species (ROS)), and 3) effects on the nervous system (possibly the primary lesion explaining the avoidance behaviour and also why enchytraeids are relatively susceptible to Zn). The adverse outcome at the organism level (reproduction EC50) could be predicted based on gene expression (male gonad development, oocyte maturation), with Zn at the EC50 affecting processes related to higher stress levels. The gene expression response was time-dependent and reflected the cascade of events taking place over-time. The 1 to 4 days of exposure design was a good strategy as it captured the time for sequence of events towards zinc adverse outcomes in E. crypticus

DRY BEAN CULTIVAR IAC ALVORADA UNDER DIFFERENT RATES OF \u3ci\u3eRHIZOBIUM\u3c/i\u3e INOCULANT IN THE PLANTING FURROW

INTRODUCTION: No publications were found regarding liquid inoculation in the planting furrow of dry bean, which indicates a demand for investigations to assist the producer in deciding which method of inoculation to adopt. Thus, the aim of this study was to evaluate the viability of liquid inoculation in the planting furrow and determine the best application rate of inoculant, using the dry bean cultivar IAC Alvorada. MATERIALS AND METHODS: A field experiment was conducted in a no-till planting system in the 2014/2015 crop season in a Latossolo Vermelho distrófico in the municipality of Lambari, MG, Brazil. The experimental design was randomized blocks with three replications and eight treatments, involving five application rates of liquid inoculant in the planting furrow (0, 120, 240, 480, and 720 mL ha-1), liquid seed inoculation (40 mL kg-1), and two controls without inoculation: one with N-urea (80 kg ha-1 N, ½ at sowing and ½ in topdressing, between the V3 and V4 stages of the crop cycle) and another without mineral N. The experimental unit (14.4 m2) consisted of six four-meter-length rows, spaced at 0.6 m, and the area effectively used was the four central rows. All the plots received base fertilization of 110 kg ha-1 of P2O5 (simple superphosphate) and 40 kg ha-1 of K2O (potassium chloride), mechanically applied during furrowing. In addition, all levels of inoculation received 20 kg Nurea ha-1, so as to meet the recommendations of Soares et al. (2016). Sowing was manual at the density of 15 seeds per meter and the cultivar used was IAC Alvorada, of semi-upright plant architecture and moderate resistance to anthracnose (Carbonell et al., 2008)

DRY BEAN CULTIVAR IAC ALVORADA UNDER DIFFERENT RATES OF \u3ci\u3eRHIZOBIUM\u3c/i\u3e INOCULANT IN THE PLANTING FURROW

INTRODUCTION: No publications were found regarding liquid inoculation in the planting furrow of dry bean, which indicates a demand for investigations to assist the producer in deciding which method of inoculation to adopt. Thus, the aim of this study was to evaluate the viability of liquid inoculation in the planting furrow and determine the best application rate of inoculant, using the dry bean cultivar IAC Alvorada. MATERIALS AND METHODS: A field experiment was conducted in a no-till planting system in the 2014/2015 crop season in a Latossolo Vermelho distrófico in the municipality of Lambari, MG, Brazil. The experimental design was randomized blocks with three replications and eight treatments, involving five application rates of liquid inoculant in the planting furrow (0, 120, 240, 480, and 720 mL ha-1), liquid seed inoculation (40 mL kg-1), and two controls without inoculation: one with N-urea (80 kg ha-1 N, ½ at sowing and ½ in topdressing, between the V3 and V4 stages of the crop cycle) and another without mineral N. The experimental unit (14.4 m2) consisted of six four-meter-length rows, spaced at 0.6 m, and the area effectively used was the four central rows. All the plots received base fertilization of 110 kg ha-1 of P2O5 (simple superphosphate) and 40 kg ha-1 of K2O (potassium chloride), mechanically applied during furrowing. In addition, all levels of inoculation received 20 kg Nurea ha-1, so as to meet the recommendations of Soares et al. (2016). Sowing was manual at the density of 15 seeds per meter and the cultivar used was IAC Alvorada, of semi-upright plant architecture and moderate resistance to anthracnose (Carbonell et al., 2008)

LocalEnergy: Local Resources for Multifunctional Tetrahedrite-based Energy: Harvesting Applications

info:eu-repo/semantics/publishedVersio

Thoracic Electrical Impedance Tomography—The 2022 Veterinary Consensus Statement

Electrical impedance tomography (EIT) is a non-invasive real-time non-ionising imaging modality that has many applications. Since the first recorded use in 1978, the technology has become more widely used especially in human adult and neonatal critical care monitoring. Recently, there has been an increase in research on thoracic EIT in veterinary medicine. Real-time imaging of the thorax allows evaluation of ventilation distribution in anesthetised and conscious animals. As the technology becomes recognised in the veterinary community there is a need to standardize approaches to data collection, analysis, interpretation and nomenclature, ensuring comparison and repeatability between researchers and studies. A group of nineteen veterinarians and two biomedical engineers experienced in veterinary EIT were consulted and contributed to the preparation of this statement. The aim of this consensus is to provide an introduction to this imaging modality, to highlight clinical relevance and to include recommendations on how to effectively use thoracic EIT in veterinary species. Based on this, the consensus statement aims to address the need for a streamlined approach to veterinary thoracic EIT and includes: an introduction to the use of EIT in veterinary species, the technical background to creation of the functional images, a consensus from all contributing authors on the practical application and use of the technology, descriptions and interpretation of current available variables including appropriate statistical analysis, nomenclature recommended for consistency and future developments in thoracic EIT. The information provided in this consensus statement may benefit researchers and clinicians working within the field of veterinary thoracic EIT. We endeavor to inform future users of the benefits of this imaging modality and provide opportunities to further explore applications of this technology with regards to perfusion imaging and pathology diagnosis

Modeling the Subsurface Structure of Sunspots

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear inversion techniques do not yet allow helioseismology to probe the internal structure with sufficient confidence to distinguish between the monolith and cluster models, the development of physically realistic sunspot models are a priority for helioseismologists. This is because they are not only important indicators of the variety of physical effects that may influence helioseismic inferences in active regions, but they also enable detailed assessments of the validity of helioseismic interpretations through numerical forward modeling. In this paper, we provide a critical review of the existing sunspot models and an overview of numerical methods employed to model wave propagation through model sunspots. We then carry out an helioseismic analysis of the sunspot in Active Region 9787 and address the serious inconsistencies uncovered by \citeauthor{gizonetal2009}~(\citeyear{gizonetal2009,gizonetal2009a}). We find that this sunspot is most probably associated with a shallow, positive wave-speed perturbation (unlike the traditional two-layer model) and that travel-time measurements are consistent with a horizontal outflow in the surrounding moat.Comment: 73 pages, 19 figures, accepted by Solar Physic

Review and application of Artificial Neural Networks models in reliability analysis of steel structures

This paper presents a survey on the development and use of Artificial Neural Network (ANN) models in structural reliability analysis. The survey identifies the different types of ANNs, the methods of structural reliability assessment that are typically used, the techniques proposed for ANN training set improvement and also some applications of ANN approximations to structural design and optimization problems. ANN models are then used in the reliability analysis of a ship stiffened panel subjected to uniaxial compression loads induced by hull girder vertical bending moment, for which the collapse strength is obtained by means of nonlinear finite element analysis (FEA). The approaches adopted combine the use of adaptive ANN models to approximate directly the limit state function with Monte Carlo simulation (MCS), first order reliability methods (FORM) and MCS with importance sampling (IS), for reliability assessment. A comprehensive comparison of the predictions of the different reliability methods with ANN based LSFs and classical LSF evaluation linked to the FEA is provided