Distribution of silicon between kamacite and taenite

Meteorites formed under highly reducing conditions can incorporate substantial amounts of Si in solid solution in their metallic phases. In enstatite meteorites, reduced Si appears in shreibersite, perryite and, in variable amounts, in the kamacite, taenite, and tetrataenite. Microprobe bulk analysis of Si in Fe,Ni particles of aubrites show a large variation from grain to grain; this large compositional range has been attributed to local equilibrium conditions in the specific T and/or fO2 environments in which they are formed. Si concentrations are homogeneous in the kamacite; in contrast, the Ni-rich phases (taenite and tetrataenite) show a characteristic Si profile. Concentrations of this element in tetrataenite are substantially higher than in the adjacent kamacite, and decrease smoothly towards the center of the taenite grain, matching very closely the M-shaped profile of Ni. Other elements with similar distribution patterns are Ge and Cu. A satisfactory explanation for this behavior cannot be given in the absence of experimental data for the diffusion of Si between alpha and gamma-Fe alloys. However, two end-member possibilities can be envisioned: the distribution of Si between kamacite and taenite may be controlled by (1) the crystallographic structure or (2) the chemical composition of the host phases. These possibilities are explored

Wage and Earnings Profiles at Older Ages

The inverted U shape of the lifetime wage profile is frequently taken to be a stylized fact. This implies a smooth decline in wages as workers approach retirement. Instead, this paper shows that the hourly wage of the typical older worker increases slightly with age for as long as he is employed full time. It declines discretely only when he enters partial retirement, a transitional period characterized by the prevalence of part-time work, and remains mostly at thereafter. That is, the wage path at older ages is best represented by a step function. The smoothly- declining profile often found in the literature is the result of aggregation over individuals who enter partial retirement at di_erent ages. This conclusion is robust to controlling for self-selection into partial and full retirement. More importantly, the transition out of full time work is a choice for most workers, and the subsequent wage change is endogenously determined. While standard labor supply models would rationalize the reduction in hours worked upon partial retirement as a response to an exogenously declining wage trajectory, the evidence presented in the paper indicates instead that workers choose to trade more leisure for a lower hourly wage in a context in which a better paid, full-time job is available. In other words, wages and hours are jointly determined at older ages. These findings have important implications for the analysis of saving and labor supply decisions over the life cycle.wage profile, earnings profile, wage determination, retirement

Use of structural adhesive joints in construction applications

The Research Group of Materials Performance works in the development of structural adhesive joints and their performance in service in collaboration with some adhesive manufacturer companies. It is sought to increase the number of adhesive manufacturer companies to work with, as well as to find construction companies interested in the application of this technology.Contrato Programa de Comercialización e Internacionalización. Sistema Regional de Investigación Científica e Innovación Tecnológica. (Comunidad de Madrid; Universidad Carlos III de Madrid

The application of gibberellic acid increases berry size of ‘Emperatriz’ seedless grape

Gibberellic acid (GA3) increases berry size of "Emperatriz" seedless grape, the response depending on the phenological stage of vine at treatment date and on the concentration applied. From berry fruit set to 21 days later, 80 mg/L GA3 increased commercial berry weight by 50%-90%, depending on the year, reaching similar size to that of "Aledo" seeded grape, used as comparison. This effect takes place through: a) a larger berry growth rate; b) an early glucose, fructose and sucrose uptake; c) an increase of absolute glucose and fructose content (mg/berry) of seedless berries up to similar values to those of seeded berries; and d) an increase of absolute berry water content but not of relative content to fresh weight, thus water potential and osmotic potential are not significantly modified by treatments. GA3 does not affect berry pericarp cell number but increases pericarp cell diameter

Political parties, two-level Governance and economic growth

Los profesores de la Universidad de Granada, Betty Agnani y Henry Aray Casanova, analizan en este Documento de Trabajo el efecto en el crecimiento económico de las regiones españolas a partir de las diferentes combinaciones de partidos políticos que gobiernan tanto a nivel central como regional. Los investigadores toman como referente datos correspondientes al período 1989-2004 en diferentes comunidades y aplican una serie variables específicas para determinar los posibles efectos que puedan derivarse en función de la titularidad en el gobierno.GrowthAccounting,PanelData,Federalism,TFP

Start-ups Defined as Portfolios of Embedded Options

In this paper we show the advantages of staged investments for venture capitalists. We develop an option-pricing model that enables to evaluate the flexibility acquired by a venture capitalist when he stages his investment process. Instead of investing a fixed amount at the beginning of the investment, the venture capitalist proceeds to a staged investment (one first investment and a second investment). The second investment will be triggered by a successful achievement of the first investment. Should the first investment be unsuccessful, the second investment will not be executed. Staging the investment in two phases enables the investor to reduce its uncertainty at the beginning of the project. As it will be demonstrated in the paper, the decision to proceed to the second investment can be modelled as a portfolio of a call option and a binary option.real options, staged investments, structured products, embedded options

HESS J1641-463, a very hard spectrum TeV gamma-ray source in the Galactic plane

HESS J1641-463 is a unique source discovered by the High Energy Stereoscopic System (H.E.S.S.) telescope array in the multi-TeV domain. The source had been previously hidden in the extended tail of emission from the bright nearby source HESS J1640-465. However, the analysis of the very-high-energy (VHE) data from the region at energies above 4 TeV revealed this new source at a significance level of 8.5$\sigma$. HESS J1641-463 showed a moderate flux level F(E > 1 TeV) = (3.64 +/- 0.44_stat +/- 0.73_sys) 10^-13 cm^-2s^-1, corresponding to 1.8% of the Crab Nebula flux above the same energy, and a hard spectrum with a photon index Gamma = 2.07 +/- 0.1_stat +/- 0.20_sys. The light curve was investigated for evidence of variability, but none was found on both short (28-min observation) and long (yearly) timescales. HESS J1641-463 is positionally coincident with the radio supernova remnant (SNR) G338.5+0.1. There is no clear X-ray counterpart of the SNR, although Chandra and XMM-Newton data reveal some weak emission that may be associated. If the emission from HESS J1641-463 is produced by cosmic ray protons colliding with the ambient gas, then the proton spectrum extends up to 0.1 PeV (99% confidence level) and likely to higher energies, > 0.27 PeV (90% confidence level). If this is the case, then HESS J1641-463 may be a member of a larger source population contributing to the Galactic cosmic-ray flux around the knee.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherland