ALBERT

Notes: Whether vertical integration between a downstream oligopolist and an upstream oligopolist is profitable for an integrated pair of firms is shown to depend on whether one means by this that profits increase no matter what other firms do, that all integrated firms are better off when all firms are integrated than when none are, or simply that no downstream-upstream pair of firms has an incentive to deviate from a situation where all firms are integrated. It is also shown to depend on the number of firms in each oligopoly and on the type of interaction that is assumed between firms that are integrated and firms that are not. In particular, it is shown that if no restriction is put on trade between integrated and nonintegrated firms, integrated firms may continue to purchase inputs from the nonintegrated upstream firms, with the goal of raising their downstream rivals' costs. Furthermore, even though firms are identical, asymmetric equilibria, where integrated and nonintegrated firms coexist, may actually arise as an outcome of the integration game.

Notes: A model of location choice by Cournot oligopolists is presented, under the assumption that R&D spillovers depend on the distance between firms. It is shown that a variety of patterns emerge. Agglomeration is optimal under certain assumptions. Geographical dispersion in a two-dimensional plane is another possible outcome.

Notes: This paper analyzes the effects of tariff reductions on horizontal mergers in a Cournot oligopoly in a two-country world. It is shown that for mergers between two domestic firms and for cross-border mergers which supply both markets from a foreign plant, unilateral tariff reduction encourages mergers which concentrate market power at the expense of mergers which reduce cost, while bilateral tariff reductions have the opposite effect, encouraging mergers which significantly reduce cost. Cross-border mergers which continue to supply each market from a local plant are discouraged by both unilateral and bilateral tariff reduction.

Notes: In a recent paper, Vemuganti, Batta, and Zhu (1996) stated that the linear programming model suggested by Moeeni and Chang (1990) could result in infeasibility. They also suggested an alternative mathematical formulation for determining the number of kanbans. The intention of this article is twofold. First, we maintain that the finding of Vemuganti et al., while valid, is based on a misplaced emphasis on the purpose of the Moeeni and Chang article. Second, we demonstrate that the Vemuganti et al. formulation is a special case of a more general model proposed by Bitran and Chang (1987).

Notes: The paper models international rivalry between a domestic firm that is going through a learning-by-doing phase, and a mature foreign rival. It is shown that the optimal production subsidy for the domestic firm depends on the degree of strategic sophistication of the foreign firm. Optimal production subsidy rules are derived under various scenarios. They are shown to be very sensitive to the specification of the game between the domestic and the foreign firms. Whether the optimal subsidy should decrease over time depends on the strategic sophistication of the foreign firm.

Notes: Acclimation of photosynthesis to growth at elevated CO2 concentration varies markedly between species. Species functionally classified as stress-tolerators (S) and ruderals (R), are thought to be incapable, or the least capable, of responding positively in terms of growth to elevated [CO2]. Is this pattern of response also apparent in leaf photosynthesis of wild S- and R-strategists? Acclimatory loss of a photosynthetic and growth response to elevated [CO2] is assumed to reflect limitation on capacity to utilize additional photosynthate. The doubling of pre-industrial global [CO2] is expected to coincide with a 3 °C increase in mean temperature which could stimulate growth; will photosynthetic capacity at elevated [CO2] be greater when the concurrent temperature increase is simulated? Five species from natural grassland of NW Europe and of contrasting ecological strategy were grown in hemispherical greenhouses, environmentally controlled to track the external microclimate. Within a replicated design, plants were grown at (i) current ambient [CO2] and temperature, (ii) elevated [CO2] (ambient + 340 μmol mol–1) and ambient temperature, (iii) ambient [CO2] and elevated temperature (ambient + 3 °C), or (iv) elevated [CO2] and elevated temperature. After 75–104 days, the CO2 response of light-saturated rates of photosynthesis (Asat) was analysed in controlled-environment cuvettes in a field laboratory. There was no acclimatory loss of photosynthetic capacity with growth in elevated [CO2] or elevated temperature over this period in Poa alpina (S), Bellis perennis (R) or Plantago lanceolata (mixed C-S-R strategist), and a significant (P ??bl 0.05) increase in capacity in Helianthemum nummularium (S) and Poa annua (R). Photosynthetic rates of leaves grown and measured in elevated [CO2] were therefore significantly higher than rates for leaves grown and measured in ambient [CO2], for all species. With the exception of Poa alpina, stomatal conductance and stomatal limitation on Asat showed no acclimatory response to growth in elevated [CO2].Carboxylation efficiency, determined from the initial slope of the response of Asat to intercellular CO2 concentration was significantly increased by elevated [CO2] and elevated temperature in H.nummularium, implying a possible increase in in vivo RubisCO activity. Increased carboxylation efficiency of this species was also reflected by an increase in the CO2- and light-saturated rates of photosynthesis, indicating an increased capacity for regeneration of the primary CO2 acceptor in photosynthesis. The results show that R-strategists and slow-growing S-strategists, are inherently capable of large increases in leaf photosynthetic capacity with growth in elevated [CO2] in contrast to expectations from growth studies. With the exception of P.annua, where there was a significant negative interaction between CO2 and temperature, concurrent increase in growth temperature had little effect on this pattern of response.