Technological Capability and Productivity Growth: An Industrialized / Industrializing Country Comparison

The importance of technical change as a crucial element explaining inter-country differences in levels and rates of change in industrial productivity has been increasingly acknowledged. Hence, growing significance has been attached to developing the capability to generate such change. However, the perceived nature of that capability (described here as technological capability) and its links to productivity growth are still poorly understood. This paper empirically explores the links between (i) technological capability (the causal variable) (ii) the generation of technical changes (the intermediate variable) and (iii) productivity growth (the end-result variable). In particular, it examines organizational dimensions of technological capability. L'importance des changements techniques comme éléments clés expliquant les différences entre pays quant aux niveaux et aux taux de productivité industrielle est de plus en plus reconnue. En conséquence, il y a un intérêt croissant quant au développement des capacités nécessaires à de tels changements. Cependant, la nature de cette capacité (dite capacité technologique) et ses liens avec la croissance de productivité est encore peu comprise. Cet article explore empiriquement les liens entre (i) la capacité technologique (variable causale) (ii) la génération de changements techniques (variable intermédiaire) et (iii) la croissance de productivité (variable résultante). En particulier, il examine les dimensions organisationnelles de la capacité technologique.technological capability, organizational systems, technical change, productivity growth, pulp and paper, India, Canada, capacité technologique, systèmes organisationnels, changement technique, croissance de productivité, pâtes et papiers, Inde, Canada

Ultrafast Transient Dynamics of Adsorbates on Surfaces Deciphered: The Case of CO on Cu(100)

Time-resolved vibrational spectroscopy constitutes an invaluable experimental tool for monitoring hot-carrier induced surface reactions. However, the absence of a full understanding on the precise microscopic mechanisms causing the transient spectral changes has been limiting its applicability. Here we introduce a robust first-principles theoretical framework that successfully explains both the nonthermal frequency and linewidth changes of the CO internal stretch mode on Cu(100) induced by femtosecond laser pulses. Two distinct processes engender the changes: electron-hole pair excitations underlie the nonthermal frequency shifts, while electron-mediated vibrational mode coupling gives rise to linewidth changes. Furthermore, the origin and precise sequence of coupling events are finally identified.Comment: Article as accepted for publication in Physical Review Letters; 5 pages, 2 figures, 1 tabl

White Dwarf Cosmochronology in the Solar Neighborhood

The study of the stellar formation history in the solar neighborhood is a powerful technique to recover information about the early stages and evolution of the Milky Way. We present a new method which consists of directly probing the formation history from the nearby stellar remnants. We rely on the volume complete sample of white dwarfs within 20 pc, where accurate cooling ages and masses have been determined. The well characterized initial-final mass relation is employed in order to recover the initial masses (1 < M/Msun < 8) and total ages for the local degenerate sample. We correct for moderate biases that are necessary to transform our results to a global stellar formation rate, which can be compared to similar studies based on the properties of main-sequence stars in the solar neighborhood. Our method provides precise formation rates for all ages except in very recent times, and the results suggest an enhanced formation rate for the solar neighborhood in the last 5 Gyr compared to the range 5 < Age (Gyr) < 10. Furthermore, the observed total age of ~10 Gyr for the oldest white dwarfs in the local sample is consistent with the early seminal studies that have determined the age of the Galactic disk from stellar remnants. The main shortcoming of our study is the small size of the local white dwarf sample. However, the presented technique can be applied to larger samples in the future.Comment: 25 pages, 10 figures, accepted for publication in the Astrophysical Journa

Early Childhood Intervention. Rationale, Timing and Efficacy

This paper provides a brief review of the economic rationale for investing in early childhood. It discusses the optimal timing of intervention, with reference to recent work in developmental neuroscience, and asks how early is early? It motivates the need for early intervention by providing an overview of the impact of adverse factors during the antenatal and early childhood period on outcomes later in life. Early childhood interventions, even poorly designed ones, are costly to implement, therefore it is vital that interventions are well-designed if they are to yield high economic and social returns. The paper therefore presents a set of guiding principles for the effectiveness of early intervention. It concludes by presenting a case for a new study of the optimal timing of interventions.Early childhood intervention, brain development, optimal timing

Potential-energy (BCS) to kinetic-energy (BEC)-driven pairing in the attractive Hubbard model

The BCS-BEC crossover within the two-dimensional attractive Hubbard model is studied by using the Cellular Dynamical Mean-Field Theory both in the normal and superconducting ground states. Short-range spatial correlations incorporated in this theory remove the normal-state quasiparticle peak and the first-order transition found in the Dynamical Mean-Field Theory, rendering the normal state crossover smooth. For $U$ smaller than the bandwidth, pairing is driven by the potential energy, while in the opposite case it is driven by the kinetic energy, resembling a recent optical conductivity experiment in cuprates. Phase coherence leads to the appearance of a collective Bogoliubov mode in the density-density correlation function and to the sharpening of the spectral function.Comment: 5 pages, 4 figure