8,419 research outputs found
Demographic Change and the Structure of Wages: A Demand-Theoretic Analysis for Brazil
With rapidly declining fertility and increased longevity the age structure of the labor force in developing countries has changed rapidly. Changing relative supply of workers by age group, and by educational attainment, can have profound effects on labor costs. Their impacts on earnings have been heavily studied in the United States but have received little attention in Asia and Latin America, where supply shocks are at least as large and have often proceeded less evenly across the economy. We use data on 502 local Brazilian labor markets from Censuses 1970-2000 to examine the extent of substitution among demographic groups as relative supply has changed. The results suggest that age-education groups are imperfect substitutes, so that larger age-education cohorts see depressed wage rates, particularly among more-educated groups. The extent of substitution has increased over time, so that the decreasing size of the least-skilled labor force today is barely raising its remaining members' wages.
Periostin increases migration and proliferation of human periodontal ligament fibroblasts challenged by tumor necrosis factor âα and Porphyromonas gingivalis lipopolysaccharides
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106894/1/jre12120.pd
Color of corn grains and carotenoid profile of importance for human health.
This work aimed at studying the influence of the color of the grains in the profile of carotenoids in four different Brazilian genotypes
Bethe approximation for self-interacting lattice trees
In this paper we develop a Bethe approximation, based on the cluster
variation method, which is apt to study lattice models of branched polymers. We
show that the method is extremely accurate in cases where exact results are
known as, for instance, in the enumeration of spanning trees. Moreover, the
expressions we obtain for the asymptotic number of spanning trees and lattice
trees on a graph coincide with analogous expressions derived through different
approaches. We study the phase diagram of lattice trees with nearest-neighbour
attraction and branching energies. We find a collapse transition at a
tricritical theta point, which separates an expanded phase from a compact
phase. We compare our results for the theta transition in two and three
dimensions with available numerical estimates.Comment: 10 pages, 3 figures, to be published in Europhysics Letter
Recommended from our members
A process centred virtual approach to support cost estimating along product life cycle
The application of engineering practices and scientific principles to the creation of cost estimates along a product life cycle is one of the basic aspects of Cost Engineering. Cost estimates are used as fundamental criteria to make design decisions in the development stage and also to make business decisions in collaboration between OEMs and their supply chain. The achievement of an estimate requires experience and knowledge of different techniques and methodologies. Key aspects on its creation are the adoption of a cost estimating process, the availability of the needed data and the proper management of the information used during the process. The collaboration between the OEM and its supplier can be facilitated by having a better common understanding of how the cost estimates have been created. The cost estimating process used is then a fundamental piece of trust. In this context, the main purpose of this paper is to present the research conducted in the definition of cost estimating processes and the virtual framework selected. They are the key elements in the development of a prototype set of virtual tools to support the creation of cost estimates, the improvement of competences of the Cost Engineering Community, and the common understanding on cost between OEMs and their supply chain
Solvent-induced micelle formation in a hydrophobic interaction model
We investigate the aggregation of amphiphilic molecules by adapting the
two-state Muller-Lee-Graziano model for water, in which a solvent-induced
hydrophobic interaction is included implicitly. We study the formation of
various types of micelle as a function of the distribution of hydrophobic
regions at the molecular surface. Successive substitution of non-polar surfaces
by polar ones demonstrates the influence of hydrophobicity on the upper and
lower critical solution temperatures. Aggregates of lipid molecules, described
by a refinement of the model in which a hydrophobic tail of variable length
interacts with different numbers of water molecules, are stabilized as the
length of the tail increases. We demonstrate that the essential features of
micelle formation are primarily solvent-induced, and are explained within a
model which focuses only on the alteration of water structure in the vicinity
of the hydrophobic surface regions of amphiphiles in solution.Comment: 11 pages, 10 figures; some rearrangement of introduction and
discussion sections, streamlining of formalism and general compression; to
appear in Phys. Rev.
- âŠ