Uniqueness of Equilibrium in the Multi-Country Ricardo Model

We present two arguments, one based on index theory, demonstrating that the multi-country Ricardo model has a unique competitive equilibrium if the aggregate demand functions exhibit gross substitutability. The result is somewhat surprising because the assumption of gross substitutability is sufficient for uniqueness in a model of exchange but not, in general, when production is included in the model.Ricardo model, Gross substitutes, Uniqueness

Strength of webs of I-beams and girders,

Cover title

Culture and Economic Security in Africa: Analysis and Implications of Indigenous Knowledge Systems

Throughout history, great nations have been built and great developmental strides attained, not by inchoate policies or untailored measures, but by well-articulated systematic policies of sustained development. For Africa, development policies and programmes must be circumscribed by a clear understanding of the crucial role of the forces of cultural and economic security on the development process. Given the giant leap in economic, political and social development by other developing continents vis-à-vis Africa, it has become imperative to ponder these questions: Do African cultures encumber or foster Africa’s economic development? Is Africa’s leadership challenge rooted in her cultural heritage? Despite huge natural resources and potentials, the crisis of Africa’s poverty and underdevelopment juxtaposing corrupt and inept national leadership warrants a reassessment of the trajectories of Africa’s development. Indigenous peoples' cultures and their knowledge systems have had a determinative effect on the lives, socioeconomic development trajectory and pace of development of Africans. Yet, these cultures and their knowledge systems have been largely misunderstood, incompletely developed or even ignored by conventional models of economic development. Understanding the crucial role of the dynamics of culture and security in economic development of nation states is important, especially given global commitment to democracy, human rights and pluralism (political, religious and cultural). This paper identifies the cultural challenges that cause the success or failure of national development in Africa. It prescribes the synthesis and remodelling of the apparatuses of cultural and economic security in the bid to foster economic development in the region. Keywords: Africa, Culture, Cultural Infrastructure, Cultural Security, Economic Security, Economic development, Indigenous knowledge systems, Nigeria DOI: 10.7176/JCSD/60-05 Publication date:June 30th 202

Sediment-mediated interactions in a densely populated infaunal assemblage: The effects of the polychaete Abarenicola pacifica

Experimental data were collected to assess the effect of a bioturbating species on associated tube-building species in an infauna! community. The deposit-feeding polychaete Abarenicola pacifica feeds below the sediment surface and deposits sediment on the surface in the form of castings...

Community structure and species diversity of the sedimentary reefs constructed by Petaloproctus socialis (Polychaeta: Maldanidae)

The macrofaunal community associated with the gregarious tube-building maldanid polychaete Petaloproctus socialis was monitored by monthly sampling from September, 1975 to November, 1976. The community is high in species diversity and species richness with 165 species found. 30% of the 210 pairwise combinations of 21 of the most abundant species showed significant positive correlations of their abundances. Few negative correlations of abundance were seen...