Global dynamics and imbalance effects in the Lucas Uzawa model : further results

In this paper we use a new analytical approach to the Lucas-Uzawa model (Boucekkine and Ruiz-Tamarit, 2007) to extend the existinc results on the dynamics and notably on the imbalance effects arising in the model. The approach does not only allow to extend the traditional analysis to any initial conditions for all variables in level, but it also permits a more general investigation of imbalance effectsLucas-Uzawa; hypergeometric functions; imbalance effects; global dynamics

Global dynamics and imbalance effects in the Lucas-Uzawa model: further results

In this paper we use a new analytical approach to the Lucas-Uzawa model (Boucekkine and Ruiz Tamarit, 2007) to extend the existing results on the dynamics, and notably on the imbalance effects arising in the model. The approach does not only allow to extend the traditional analysis to any initial conditions and for all variables in level, but it also permits a more general investigation of imbalance effects.Lucas-Uzawa, hypergeometric functions, imbalance effects, global dynamics

Growth vs. level effect of population change on economic development: An inspection into human-capital-related mechanisms

This paper studies the different mechanisms and the dynamics through which demography is channelled to the economy. We analyze the role of demographic changes in the economic development process by studying the transitional and the long-run impact of both the rate of population growth and the initial population size on the levels of per capita human capital and income. We do that in an enlarged Lucas-Uzawa model with intergenerational altruism. In contrast to the existing theoretical literature, the long-run level effects of demographic changes, i.e. their impact on the levels of the variables along the balanced growth path, are deeply characterized in addition to the more standard long-run growth effects. We prove that the level effect of the population rate of growth is non-negative (positive in the empirically most relevant case) for the average level of human capital, but a priori ambiguous for the level of per capita income due to the interaction of three transmission mechanisms of demographic shocks, a standard one (dilution) and two non-standard (altruism and human capital accumulation). Overall, the sign of the level effects of population growth depend on preference and technology parameters, but numerically we show that the joint negative effect of dilution and altruism is always stronger than the finduced positive human capital effect. The growth effect of population growth depends basically on the attitude to intergenerational altruism and intertemporal substitution. Moreover, we also prove that the long-run level effects of population size on per capita human capital and income may be negative, nil, or positive, depending on the relationship between preferences and technology, while its growth effect is zero. Finally, we show that the model is able to replicate complicated time relationships between economic and demographic changes. In particular, it entails a negative effect of population growth on per capita income, which dominates in the initial periods, and a positive effect which restores a positive correlation between population growth and economic performance in the long term.Human Capital, Population Growth, Population Size, Endogenous Growth, Level Effect, Growth Effect

Optical absorption of divalent metal tungstates: Correlation between the band-gap energy and the cation ionic radius

We have carried out optical-absorption and reflectance measurements at room temperature in single crystals of AWO4 tungstates (A = Ba, Ca, Cd, Cu, Pb, Sr, and Zn). From the experimental results their band-gap energy has been determined to be 5.26 eV (BaWO4), 5.08 eV (SrWO4), 4.94 eV (CaWO4), 4.15 eV (CdWO4), 3.9-4.4 eV (ZnWO4), 3.8-4.2 eV (PbWO4), and 2.3 eV (CuWO4). The results are discussed in terms of the electronic structure of the studied tungstates. It has been found that those compounds where only the s electron states of the A2+ cation hybridize with the O 2p and W 5d states (e.g BaWO4) have larger band-gap energies than those where also p, d, and f states of the A2+ cation contribute to the top of the valence band and the bottom of the conduction band (e.g. PbWO4). The results are of importance in view of the large discrepancies existent in prevoiusly published data.Comment: 16 pages, 3 figures, 1 tabl

Control de la madurez en frutos por medio de ensayos de impacto.

En anteriores trabajos se ha observado que la respuesta de los frutos a un impacto mecánico está muy influida por su estado de madurez. Se realizaron ensayos de impacto sobre peras cv. Limonera, a lo largo de 12 semanas de conservación frigorífica y de maduración controlada. El impacto desde 4 cm de altura (equivalente a 0,02 J) resulta no destructivo y puede utilizarse para la determinación del estado de madurez de estos frutos. Por métodos de regresión lineal múltiple sobre los 15 para metros del impacto más representativos se obtienen buenas p r e dicciones de la madurez, representada por la fuerza de corte de probetas de pulpa, FC (N)

Analysis of CMB maps with 2D wavelets

We consider the 2D wavelet transform with two scales to study sky maps of temperature anisotropies in the cosmic microwave background radiation (CMB). We apply this technique to simulated maps of small sky patches of size 12.8 \times 12.8 square degrees and 1.5' \times 1.5' pixels. The relation to the standard approach, based on the cl's is established through the introduction of the scalogram. We consider temperature fluctuations derived from standard, open and flat-Lambda CDM models. We analyze CMB anisotropies maps plus uncorrelated Gaussian noise (uniform and non-uniform) at idfferent S/N levels. We explore in detail the denoising of such maps and compare the results with other techniques already proposed in the literature. Wavelet methods provide a good reconstruction of the image and power spectrum. Moreover, they are faster than previously proposed methods.Comment: latex file 7 pages + 5 postscript files + 1 gif file; accepted for publication in A&A

Semiempirical formula for two-nucleon emission induced by short-range correlations in electron and neutrino scattering

A semiempirical formula is proposed for the emission cross section of two correlated nucleons. We assume that the two-particle emission response is proportional to the two-particle two-hole phase space multiplied by an averaged single-nucleon response. The effect of the short-range correlations is encoded in a correlation coefficient that is linked to an average of the high-momentum distribution of a nucleon pair. The correlation coefficient depends only on the momentum transfer and is obtained from a fit to the tail of the phenomenological scaling function. We present predictions for the inclusive two-nucleon emission cross section induced by electrons and neutrinos including short-range correlations and meson-exchange currents.Comment: 14 pages, 8 figures. Major revision, with 5 more pages, a new section, an appendix and a figur

Impact of an intermittent and localized cooling intervention on skin temperature, sleep quality and energy expenditure in free-living, young, healthy adults

Where people live and work together it is not always possible to modify the ambient temperature; ways must therefore be found that allow individuals to feel thermally comfortable in such settings. The Embr Wave (R) is a wrist-worn device marketed as a 'personal thermostat' that can apply a local cooling stimulus to the skin. The aim of the present study was to determine the effect of an intermittent mild cold stimulus of 25 degrees C for 15-20 s every 5 min over 3.5 days under free-living conditions on 1) skin temperature, 2) perception of skin temperature, 3) sleep quality and 4) resting energy expenditure (REE) in young, healthy adults. Ten subjects wore the device for 3.5 consecutive days. This intervention reduced distal skin temperature after correcting for personal ambient temperature (P = 0.051). Thus, this intermittent mild cold regime can reduce distal skin temperature, and wearing it under free-living conditions for 3.5 days does not seem to impair the perception of skin temperature and sleep quality or modify REE.The study was funded by the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigacion Sanitaria del Instituto de Salud Carlos III (PI13/01393 and CB16/10/00239) and PTA 12264-I, Retos de la Sociedad (DEP2016-79512-R), and European Regional Development Funds (ERDF). Other funders included the Spanish Ministry of Education (FPU 16/05159, 15/04059 and 19/02326), the Fundacion Iberoamericana de Nutricion (FINUT), the Redes Tematicas De Investigacion Cooperativa RETIC (Red SAMID RD16/0022), the AstraZeneca Health Care Foundation, the University of Granada Plan Propio de Investigacion 2016 (Excellence actions: Unit of Excellence on Exercise, Nutrition and Health [UCEENS]), and by the Junta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades (ERDF, SOMM17/6107/UGR). AMT was supported by Seneca Foundation through grant 19899/GERM/15 and the Ministry of Science Innovation and Universities RTI2018-093528-B-I0, as well as DJP (MINECO; RYC-2014-16938). BMT was supported by an individual postdoctoral grant from the Fundacion Alfonso Martin Escudero. We thank Dr. Matt Smith of Embr Labs Inc. for configuring the Embr Wave (R) devices used in this experiment

Observational constraints to boxy/peanut bulge formation time

Boxy/peanut bulges are considered to be part of the same stellar structure as bars and both could be linked through the buckling instability. The Milky Way is our closest example. The goal of this letter is determining if the mass assembly of the different components leaves an imprint in their stellar populations allowing to estimate the time of bar formation and its evolution. To this aim we use integral field spectroscopy to derive the stellar age distributions, SADs, along the bar and disc of NGC 6032. The analysis shows clearly different SADs for the different bar areas. There is an underlying old (>=12 Gyr) stellar population for the whole galaxy. The bulge shows star formation happening at all times. The inner bar structure shows stars of ages older than 6 Gyrs with a deficit of younger populations. The outer bar region presents a SAD similar to that of the disc. To interpret our results, we use a generic numerical simulation of a barred galaxy. Thus, we constrain, for the first time, the epoch of bar formation, the buckling instability period and the posterior growth from disc material. We establish that the bar of NGC 6032 is old, formed around 10 Gyr ago while the buckling phase possibly happened around 8 Gyr ago. All these results point towards bars being long-lasting even in the presence of gas.Comment: Accepted for publication in MNRAS Letter