977 resultados para Maritime Specialization
Resumo:
We develop a model to analyse the implications of firing costs on incentives for R&D and international specialization. The Key idea is paying the firing cost, the country with a rigid labor market will tend to produce relatively secure goods, at a late stage of their product life cycle. Under international trade, an international product cycle emerges where, roughly, new goods are first produced in the low firing cost country will specialize in 'secondary innovations', that is, improvements in existing goods, while the low firing cost country will more specialize in 'primary innovation', that is, invention of new goods.
Resumo:
Previous morphological and cytological analyses have suggested that the arctic shrew (Sorex arcticus) as currently recognized may be two distinct species. Specifically, those studies demonstrated considerable differentiation between the putative subspecies S. a. maritimensis and one or both of the other two subspecies, S. a. arcticus and S. a. laricorum. Phylogenetic analysis of 546 base pairs of cytochrome b sequence data from 10 arctic shrews from across Canada indicates that maritimensis is the sister-group to arcticus + laricorum. Furthermore, there is considerable genetic divergence between maritimensis and the other two putative subspecies (similar to8-9%; Kimura's two-parameter distance). Given that maritimensis and arcticus + laricorum appear to be reciprocally monophyletic clades with considerable genetic divergence (i.e., greater than that between other recognized pairs of sister-species within the S. araneus-arcticus group), we propose that S. maritimensis be recognized as a distinct species. The proportion of third-position transversion substitutions between S. arcticus and S. maritimensis suggests that these two species shared a common ancestor approximately 2.4 million years ago.
Resumo:
Moral codes are produced and enforced by more or less specialized means and are subject to standard economic forces. This paper argues that the intermediary role played by the Catholic Church between God and Christians, a key difference from Protestantism, faces the standard trade-off of specialization benefits and agency costs. It applies this trade-off hypothesis to confession of sins to priests, an institution that epitomizes such intermediation, showing that this hypothesis fits cognitive, historical and econometric evidence better than a simpler rent-seeking story. In particular, Catholics who confess more often are observed to comply more with the moral code; however, no relationship is observed between mass attendance and moral compliance. The data also links the current decline in confession to the rise in education, which makes moral self-enforcement less costly, and to the productivity gap suffered by confession services, given its necessarily interpersonal nature.
Resumo:
This paper studies the effect of parental education on the educational attainmentof children in the US for cohorts born after 1910. Importantly, we allow for cohort-specificdifferences by gender. Our estimates show that paternal education has been more importantfor the attainment of male children (paternal specialization on sons). However, maternalspecialization (on daughters) seems to have appeared only for cohorts born after 1955. Weinterpret these results as evidence that fathers are more important role models for sonswhile mothers are a more important reference for daughters. We argue that our results arerobust to the presence of hereditary unobserved ability and conjecture that both types ofgender specialization may have been present in earlier cohorts too.
Resumo:
We develop a model to analyse the implications of firing costs on incentivesfor R&D and international specialization. The Key idea is paying the firingcost, the country with a rigid labor market will tend to produce relativelysecure goods, at a late stage of their product life cycle.Under international trade, an international product cycle emerges where,roughly, new goods are first produced in the low firing cost country willspecialize in 'secondary innovations', that is, improvements in existinggoods, while the low firing cost country will more specialize in 'primaryinnovation', that is, invention of new goods.
Resumo:
Understanding tree recruitment is needed to forecast future forest distribution. Many studies have reported the relevant ecological factors that affect recruitment success in trees, but the potential for genetic-based differences in recruitment has often been neglected. In this study, we established a semi-natural reciprocal sowing experiment to test for local adaptation and microenvironment effects (evaluated here by canopy cover) in the emergence and early survival of maritime pine (Pinus pinaster Aiton), an emblematic Mediterranean forest tree. A novel application of molecular markers was also developed to test for family selection and, thus, for potential genetic change over generations. Overall, we did not find evidence to support local adaptation at the recruitment stage in our semi-natural experiment. Moreover, only weak family selection (if any) was found, suggesting that in stressful environments with low survival, stochastic processes and among-year climate variability may drive recruitment. Nevertheless, our study revealed that, at early stages of recruitment, microenvironments may favor the population with the best adapted life strategy, irrespectively of its (local or non-local) origin. We also found that emergence time is a key factor for seedling survival in stressful Mediterranean environments. Our study highlights the complexity of the factors influencing the early stages of establishment of maritime pine and provides insights into possible management actions aimed at environmental change impact mitigation. In particular, we found that the high stochasticity of the recruitment process in stressful environments and the differences in population-specific adaptive strategies may difficult assisted migration schemes.