Interaction of a discrete breather with a lattice junction

We study the scattering of a moving discrete breather (DB) on a junction in a Fermi-Pasta-Ulam chain consisting of two segments with different masses of the particles. We consider four distinct cases: (i) a light-heavy (abrupt) junction in which the DB impinges on the junction from the segment with lighter mass, (ii) a heavy-light junction, (iii) an up mass ramp in which the mass in the heavier segment increases continuously as one moves away from the junction point, and (iv) a down mass ramp. Depending on the mass difference and DB characteristics (frequency and velocity), the DB can either reflect from, or transmit through, or get trapped at the junction or on the ramp. For the heavy-light junction, the DB can even split at the junction into a reflected and a transmitted DB. The latter is found to subsequently split into two or more DBs. For the down mass ramp the DB gets accelerated in several stages, with accompanying radiation (phonons). These results are rationalized by calculating the Peierls-Nabarro barrier for the various cases. We also point out implications of our results in realistic situations such as electron-phonon coupled chains.

Confinement of discrete breathers in inhomogeneously profiled nonlinear chains

We investigate numerically the scattering of a moving discrete breather on a pair of junctions in a Fermi-Pasta-Ulam chain. These junctions delimit an extended region with different masses of the particles. We consider (i) a rectangular trap, (ii) a wedge shaped trap, and (iii) a smoothly varying convex or concave mass profile. All three cases lead to DB confinement, with the ease of trapping depending on the profile of the trap. We also study the collision and trapping of two DBs within the profile as a function of trap width, shape, and approach time at the two junctions. The latter controls whether one or both DBs are trapped.

Lead and zinc in the structure of organic and mineral soil components

In addition to the more reactive forms, metals can occur in the structure of minerals, and the sum of all these forms defines their total contents in different soil fractions. The isomorphic substitution of heavy metals for example alters the dimensions of the unit cell and mineral size. This study proposed a method of chemical fractionation of heavy metals, using more powerful extraction methods, to remove the organic and different mineral phases completely. Soil samples were taken from eight soil profiles (0-10, 10-20 and 20-40 cm) in a Pb mining and metallurgy area in Adrianópolis, Paraná, Brazil. The Pb and Zn concentrations were determined in the following fractions (complete phase removal in each sequential extraction): exchangeable; carbonates; organic matter; amorphous and crystalline Fe oxides; Al oxide, amorphous aluminosilicates and kaolinite; and residual fractions. The complete removal of organic matter and mineral phases in sequential extractions resulted in low participation of residual forms of Pb and Zn in the total concentrations of these metals in the soils: there was lower association of metals with primary and 2:1 minerals and refractory oxides. The powerful methods used here allow an identification of the complete metal-mineral associations, such as the occurrence of Pb and Zn in the structure of the minerals. The higher incidence of Zn than Pb in the structure of Fe oxides, due to isomorphic substitution, was attributed to a smaller difference between the ionic radius of Zn2+ and Fe3+.

Insulin and insulin-like growth factor I receptors utilize different G protein signaling components.

We examined the role of heterotrimeric G protein signaling components in insulin and insulin-like growth factor I (IGF-I) action. In HIRcB cells and in 3T3L1 adipocytes, treatment with the Galpha(i) inhibitor (pertussis toxin) or microinjection of the Gbetagamma inhibitor (glutathione S-transferase-betaARK) inhibited IGF-I and lysophosphatidic acid-stimulated mitogenesis but had no effect on epidermal growth factor (EGF) or insulin action. In basal state, Galpha(i) and Gbeta were associated with the IGF-I receptor (IGF-IR), and after ligand stimulation the association of IGF-IR with Galpha(i) increased concomitantly with a decrease in Gbeta association. No association of Galpha(i) was found with either the insulin or EGF receptor. Microinjection of anti-beta-arrestin-1 antibody specifically inhibited IGF-I mitogenic action but had no effect on EGF or insulin action. beta-Arrestin-1 was associated with the receptors for IGF-I, insulin, and EGF in a ligand-dependent manner. We demonstrated that Galpha(i), betagamma subunits, and beta-arrestin-1 all play a critical role in IGF-I mitogenic signaling. In contrast, neither metabolic, such as GLUT4 translocation, nor mitogenic signaling by insulin is dependent on these protein components. These results suggest that insulin receptors and IGF-IRs can function as G protein-coupled receptors and engage different G protein partners for downstream signaling.

Surface characterization techniques for determining the root-mean-square roughness and power spectral densities of optical components

Surface topography and light scattering were measured on 15 samples ranging from those having smooth surfaces to others with ground surfaces. The measurement techniques included an atomic force microscope, mechanical and optical profilers, confocal laser scanning microscope, angle-resolved scattering, and total scattering. The samples included polished and ground fused silica, silicon carbide, sapphire, electroplated gold, and diamond-turned brass. The measurement instruments and techniques had different surface spatial wavelength band limits, so the measured roughnesses were not directly comparable. Two-dimensional power spectral density (PSD) functions were calculated from the digitized measurement data, and we obtained rms roughnesses by integrating areas under the PSD curves between fixed upper and lower band limits. In this way, roughnesses measured with different instruments and techniques could be directly compared. Although smaller differences between measurement techniques remained in the calculated roughnesses, these could be explained mostly by surface topographical features such as isolated particles that affected the instruments in different ways.

Ammonia volatilization and yield components after application of polymer-coated urea to maize

A form of increasing the efficiency of N fertilizer is by coating urea with polymers to reduce ammonia volatilization. The aim of this study was to evaluate the effect of polymer-coated urea on the control of ammonia volatilization, yield and nutritional characteristics of maize. The experiment was carried out during one maize growing cycle in 2009/10 on a Geric Ferralsol, inUberlândia, MG, Brazil. Nitrogen fertilizers were applied as topdressing on the soil surface in the following urea treatments: polymer-coated urea at rates of 45, 67.5 and 90 kg ha-1 N and one control treatment (no N), in randomized blocks with four replications. Nitrogen application had a favorable effect on N concentrations in leaves and grains, Soil Plant Analysis Development (SPAD) chlorophyll meter readings and on grain yield, where as coated urea had no effect on the volatilization rates, SPAD readings and N leaf and grain concentration, nor on grain yield in comparison to conventional fertilization.

Impacts of deforestation on water balance components of a watershed on the Brazilian East Coast

The Brazilian East coast was intensely affected by deforestation, which drastically cut back the original biome. The possible impacts of this process on water resources are still unknown. The purpose of this study was an evaluation of the impacts of deforestation on the main water balance components of the Galo creek watershed, in the State of Espírito Santo, on the East coast of Brazil. Considering the real conditions of the watershed, the SWAT model was calibrated with data from 1997 to 2000 and validated for the period between 2001 and 2003. The calibration and validation processes were evaluated by the Nash-Sutcliffe efficiency coefficient and by the statistical parameters (determination coefficient, slope coefficient and F test) of the regression model adjusted for estimated and measured flow data. After calibration and validation of the model, new simulations were carried out for three different land use scenarios: a scenario in compliance with the law (C1), assuming the preservation of PPAs (permanent preservation areas); an optimistic scenario (C2), which considers the watershed to be almost entirely covered by native vegetation; and a pessimistic scenario (C3), in which the watershed would be almost entirely covered by pasture. The scenarios C1, C2 and C3 represent a soil cover of native forest of 76, 97 and 0 %, respectively. The results were compared with the simulation, considering the real scenario (C0) with 54 % forest cover. The Nash-Sutcliffe coefficients were 0.65 and 0.70 for calibration and validation, respectively, indicating satisfactory results in the flow simulation. A mean reduction of 10 % of the native forest cover would cause a mean annual increase of approximately 11.5 mm in total runoff at the watershed outlet. Reforestation would ensure minimum flows in the dry period and regulate the maximum flow of the main watercourse of the watershed.

Water Balance Components in Covered and Uncovered Soil Growing Irrigated Muskmelon

ABSTRACT Knowledge of the terms (or processes) of the soil water balance equation or simply the components of the soil water balance over the cycle of an agricultural crop is essential for soil and water management. Thus, the aim of this study was to analyze these components in a Cambissolo Háplico (Haplocambids) growing muskmelon (Cucumis melo L.) under drip irrigation, with covered and uncovered soil, in the municipality of Baraúna, State of Rio Grande do Norte, Brazil (05º 04’ 48” S, 37º 37’ 00” W). Muskmelon, variety AF-646, was cultivated in a flat experimental area (20 × 50 m). The crop was spaced at 2.00 m between rows and 0.35 m between plants, in a total of ten 50-m-long plant rows. At points corresponding to ⅓ and ⅔ of each plant row, four tensiometers (at a distance of 0.1 m from each other) were set up at the depths of 0.1, 0.2, 0.3, and 0.4 m, adjacent to the irrigation line (0.1 m from the plant row), between two selected plants. Five random plant rows were mulched using dry leaves of banana (Musa sp.) along the drip line, forming a 0.5-m-wide strip, which covered an area of 25 m2 per of plant row with covered soil. In the other five rows, there was no covering. Thus, the experiment consisted of two treatments, with 10 replicates, in four phenological stages: initial (7-22 DAS - days after sowing), growing (22-40 DAS), fruiting (40-58 DAS) and maturation (58-70 DAS). Rainfall was measured with a rain gauge and water storage was estimated by the trapezoidal method, based on tensiometer readings and soil water retention curves. For soil water flux densities at 0.3 m, the tensiometers at the depths of 0.2, 0.3, and 0.4 m were considered; the tensiometer at 0.3 m was used to estimate soil water content from the soil water retention curve at this depth, and the other two to calculate the total potential gradient. Flux densities were calculated through use of the Darcy-Buckingham equation, with hydraulic conductivity determined by the instantaneous profile method. Crop actual evapotranspiration was calculated as the unknown of the soil water balance equation. The soil water balance method is effective in estimating the actual evapotranspiration of irrigated muskmelon; there was no significant effect of soil coverage on capillary rise, internal drainage, crop actual evapotranspiration, and muskmelon yield compared with the uncovered soil; the transport of water caused by evaporation in the uncovered soil was controlled by the break in capillarity at the soil-atmosphere interface, which caused similar water dynamics for both management practices applied.

Precast Concrete Elements for Accelerated Bridge Construction Final Report, Volume 1-1. Laboratory Testing of Precast Substructure Components: Boone County Bridge, January 2009

In July 2006, construction began on an accelerated bridge project in Boone County, Iowa that was composed of precast substructure elements and an innovative, precast deck panel system. The superstructure system consisted of full-depth deck panels that were prestressed in the transverse direction, and after installation on the prestressed concrete girders, post-tensioned in the longitudinal direction. Prior to construction, laboratory tests were completed on the precast abutment and pier cap elements. The substructure testing was to determine the punching shear strength of the elements. Post-tensioning testing and verification of the precast deck system was performed in the field. The forces in the tendons provided by the contractor were verified and losses due to the post-tensioning operation were measured. The stress (strain) distribution in the deck panels due to the post-tensioning was also measured and analyzed. The entire construction process for this bridge system was documented. Representatives from the Boone County Engineers Office, the prime contractor, precast fabricator, and researchers from Iowa State University provided feedback and suggestions for improving the constructability of this design.

A comment on the cost of capital for investments with non-homogeneous components

In this paper, the expression for the cost of capital is derived when net and replacement investments exhibit differences in their effective prices due to a different fiscal treatment. It is shown that, contrary to previous results in the literature, the cost of capital should be constructed under an opportunity cost criterion rather than a historical one. This result has some important economic consequences, since the optimizing firm will take into account not only the effective price for the new investments but also consider the opportunity cost of replacing them.

Discrete analysis of dividend payments in a non-life insurance portfolio

The process of free reserves in a non-life insurance portfolio as defined in the classical model of risk theory is modified by the introduction of dividend policies that set maximum levels for the accumulation of reserves. The first part of the work formulates the quantification of the dividend payments via the expectation of their current value under diferent hypotheses. The second part presents a solution based on a system of linear equations for discrete dividend payments in the case of a constant dividend barrier, illustrated by solving a specific case.

Géopatrimoines des trois Chablais. Identification et valorisation des témoins glaciaires

Cette recherche s'applique aux témoins glaciaires des Chablais dans quatre de leurs dimensions : géopatrimoine, connaissance objective, inventaire de géosites et valorisation. Elle est organisée sur le canevas d'un processus de patrimonialisation auquel elle participe et qu'elle interroge à la fois. En 2009, débutait le projet 123 Chablais, pour une durée de quatre ans. Il concernait l'ensemble du territoire chablaisien, réparti sur deux pays (France et Suisse) et trois entités administratives (département de la Haute-Savoie, cantons de Vaud et du Valais). Ce projet, élaboré dans le cadre du programme Interreg IV France-Suisse, avait pour but de dynamiser le développement économique local en s'appuyant sur les patrimoines régionaux. Le géopatrimoine, identifié comme une de ces ressources, faisait donc l'objet de plusieurs actions, dont cette recherche. En parallèle, le Chablais haut-savoyard préparait sa candidature pour rejoindre l'European Geopark Network (EGN). Son intégration, effective dès 2012, a fait de ce territoire le cinquième géoparc français du réseau. Le Geopark du Chablais fonde son identité géologique sur l'eau et la glace, deux thématiques intimement liées aux témoins glaciaires. Dans ce contexte d'intérêt pour le géopatrimoine local et en particulier pour le patrimoine glaciaire, plusieurs missions ont été assignées à cette recherche qui devait à la fois améliorer la connaissance objective des témoins glaciaires, inventorier les géosites glaciaires et valoriser le patrimoine glaciaire. Le premier objectif de ce travail était d'acquérir une vision synthétique des témoins glaciaires. Il a nécessité une étape de synthèse bibliographique ainsi que sa spatialisation, afin d'identifier les lacunes de connaissance et la façon dont ce travail pouvait contribuer à les combler. Sur cette base, plusieurs méthodes ont été mises en oeuvre : cartographie géomorphologique, reconstitution des lignes d'équilibre glaciaires et datations de blocs erratiques à l'aide des isotopes cosmogéniques produits in situ. Les cartes géomorphologiques ont été élaborées en particulier dans les cirques et vallons glaciaires. Les datations cosmogéniques ont été concentrées sur deux stades du glacier du Rhône : le Last Local Glacial Maximum (LLGM) et le stade de Monthey. Au terme de cette étape, les spécificités du patrimoine glaciaire régional se sont révélées être 1) une grande diversité de formes et des liens étroits avec différents autres processus géomorphologiques ; 2) une appartenance des témoins glaciaires à dix grandes étapes de la déglaciation du bassin lémanique. Le second objectif était centré sur le processus d'inventaire des géosites glaciaires. Nous avons mis l'accent sur la sélection du géopatrimoine en développant une approche basée sur deux axes (temps et espace) identifiés dans le volet précédent et avons ainsi réalisé un inventaire à thèmes, composé de 32 géosites. La structure de l'inventaire a également été explorée de façon à intégrer des critères d'usage de ces géosites. Cette démarche, soutenue par une réflexion sur les valeurs attribuées au géopatrimoine et sur la façon d'évaluer ces valeurs, nous a permis de mettre en évidence le point de vue anthropo - et scientifico - centré qui prévaut nettement dans la recherche européenne sur le géopatrimoine. L'analyse des résultats de l'inventaire a fait apparaître quelques caractéristiques du patrimoine glaciaire chablaisien, discret, diversifié, et comportant deux spécificités exploitables dans le cadre d'une médiation scientifique : son statut de « berceau de la théorie glaciaire » et ses liens étroits avec des activités de la vie quotidienne, en tant que matière première, support de loisir ou facteur de risque. Cette recherche a débouché sur l'élaboration d'une exposition itinérante sur le patrimoine glaciaire des Chablais. Ce produit de valorisation géotouristique a été conçu pour sensibiliser la population locale à l'impact des glaciers sur son territoire. Il présente une série de sept cartes de stades glaciaires, encadrées par les deux mêmes thématiques, l'histoire de la connaissance glaciaire d'une part, les témoins glaciaires et la société, d'autre part. -- This research focuses on glacial witnesses in the Chablais area according to four dimensions : geoheritage, objective knowledge, inventory and promotion of geosites. It is organized on the model of an heritage's process which it participates and that it questions both. In 2009, the project 123 Chablais started for a period of four years. It covered the entire chablaisien territory spread over two countries and three administrative entities (département of Haute-Savoie, canton of Vaud, canton of Valais). This project, developed in the framework of the Interreg IV France-Switzerland program, aimed to boost the local development through regional heritage. The geoheritage identified as one of these resources, was therefore the subject of several actions, including this research. In parallel, the French Chablais was preparing its application to join the European Geopark Network (EGN). Its integration, effective since 2012, made of this area the fifth French Geopark of the network. The Chablais Geopark geological identity was based on water and ice, two themes closely linked to the glacial witnesses. In this context of interest for the regional geoheritage and especially for the glacial heritage, several missions have been assigned to this research which should improve objective knowledge of glacial witnesses, inventory and assess glacial geosites. The objective knowledge's component was to acquire a synthetic vision of the glacial witnesses. It required a first bibliography synthesis step in order to identify gaps in knowledge and how this work could help to fill them. On this basis, several methods have been implemented: geomorphological mapping, reconstruction of the equilibrium-line altitude and dating of glacial erratic blocks using cosmogenic isotopes produced in situ. Geomorphological maps have been developed especially in glacial cirques and valleys. Cosmogenic datings were concentrated on two stages of the Rhone glacier: the Last Local Glacial Maximum (LLGM) and « the stage of Monthey ». After this step, the specificities of the regional glacial heritage have emerged to us as 1) a wide variety of forms and links to various other geomorphological processes; 2) belonging of glacial witnesses to ten major glacial stages of Léman Lake's deglaciation. In the inventory of glacial geosites component we focused on the selection of geoheritage. We developed an approach based on two axes (time and space) identified in the preceding components. We obtained a thematic inventory, consisting of 32 geosites. The structure of the inventory was also explored in the aim to integrate use criteria of geosites. This approach, supported by a thought on the values attributed to the geoheritage and how to assess these values allowed us to highlight the point of view much anthropological - and scientific -centered prevailing in the European research on geoheritage. The analysis of the inventory's results revealed some characteristics of chablaisien glacial heritage, discrete, diverse, and with two features exploitable in the context of a scientific mediation: its status as « cradle of the glacial theory » and its close links with activities of daily life, as raw material, leisure support and risk factor. This research leads to the development of a traveling exhibition on the glacial heritage of the Chablais area. It presents a series of seven glacial stage's cards, framed by the two themes mentioned above: « history of glacial knowledge » and « glacial witnesses and society ».