Heterogeneous substitution systems revisited

Matthes and Uustalu (TCS 327(1-2):155-174, 2004) presented a categorical description of substitution systems capable of capturing syntax involving binding which is independent of whether the syntax is made up from least or greatest fixed points. We extend this work in two directions: we continue the analysis by creating more categorical structure, in particular by organizing substitution systems into a category and studying its properties, and we develop the proofs of the results of the cited paper and our new ones in UniMath, a recent library of univalent mathematics formalized in the Coq theorem prover.Comment: 24 page

Transport Costs and the Size Distribution of a Linearly Arranged System of Cities

The question regarding the effects of changing transports costs on the size distribution of cities is an important topic of systems of cities research. The so-called New Economic Geography has already given some answers to this question. One central assumption in this kind of model is a very particular, simplified spatial structure. This contribution investigates the consequences of changing transport costs for a system of cities that are located equidistantly on a straight line. In the case of rising transport costs, the main outcome of this model is worker concentration in the central large cities, while the peripheral regions lose residents.transport costs, agglomeration, urban systems

Revisiting Import-Substituting Industrialisation in Post-War Brazil

This article reassesses the classic period of Import-Substituting Industrialisation (ISI) in Brazil between 1945 and 1979. New data presented here show that Brazilian industry achieved significant labour productivity growth during the post-war years and became more technologically sophisticated, when measured by manufacturing exports and evidence of specific industries and firms. We also found that Brazil’s labour productivity growth lagged behind what was achieved in other industrialising and developed countries from the mid-1970s. Technological advances were slow and uneven, and most firms relatively backward. Overall these results suggest that a highly heterogeneous structure became a major feature of Brazilian industrialisation, rather than widespread inefficiency and technological stagnation as argued by the dominant interpretation of ISI in Latin America.Import-Substituting Industrialisation; Productivity; Technology; Brazil; Latin America

On Capturing Oil Rents with a National Excise Tax Revisited

In this paper the scope of Bergstrom’s (1982) results is studied. Moreover, his analysis is extended assuming that extraction cost is directly related to accumulated extractions. For the case of a competitive market it is found that the optimal policy is a constant tariff if extraction is costless. However, with depletion effects, the optimal tariff must ultimately be decreasing. For the case of a monopolistic market the results depend crucially on the kind of strategies the importing country governments can play and on whether the monopolist chooses the price or extraction rate. For a price-setting monopolist it is shown that the importing countries cannot use a tariff to capture monopoly rents if they are constrained to use open-loop strategies, even if the governments sign a tariff agreement. This result is drastically modified if the importing countries in the tariff agreement use Markov (feedback) strategies. For a quantity-setting monopolist the nature of the game changes and the importing country governments find it advantageous to set a tariff on resource importations. Moreover, in this case the importing countries in a tariff agreement enjoy a strategic advantage which allows them to behave as a leader.Tariffs, Tariff agreements, Non renewable resources, Depletion effects, Price-setting monopolist, Quantity-setting monopolist, Differential games, Open-loop strategies, Linear strategies, Markov-perfect Nash equilibrium, Markov-perfect Stackelberg equilibrium

Induced Innovation in U.S. Agriculture: Time-series, Direct Econometric, and Nonparametric Tests

The hypothesis of induced innovation is tested for U.S. agriculture using a high-quality state-level panel data set and three disparate testing techniques – time series, direct econometric, and nonparametric. We find little support for the hypothesis. That conclusion is robust across testing techniques. However, as with all empirical tests of this hypothesis conducted to date, ours focus only on the demand side of the hypothesis. The hypothesis could have been rejected simply because the marginal cost of developing and implementing input-saving technologies for the relatively expensive inputs is greater than for the relatively cheap inputs.econometric, induced innovation, nonparametric, time series, 2-stage CES

Public Capital and Income Distribution: a Marriage of Hicks & Newman-Read

This paper examines how publicly provided inputs could affect income distribution. By applying the Newman-Read production function- a generalized Cobb-Douglas production function- to Hicks's idea of the determinant of factor share, such usually complex dynamics remain analytically tractable. The paper shows that whether public capital has an effect on income distribution dynamics depends on its elasticity of substitution to private capital. If the elasticity of substitution of public capital to private capital is greater than unity, then an investment in public capital increases its relative income share and, hence, decreases the private capital share. In such a case, public capital would have a positive impact on income distribution dynamics.Income distribution, public capital, economic growth

A 2-pyridone-amide inhibitor targets the glucose metabolism pathway of Chlamydia trachomatis.

UnlabelledIn a screen for compounds that inhibit infectivity of the obligate intracellular pathogen Chlamydia trachomatis, we identified the 2-pyridone amide KSK120. A fluorescent KSK120 analogue was synthesized and observed to be associated with the C. trachomatis surface, suggesting that its target is bacterial. We isolated KSK120-resistant strains and determined that several resistance mutations are in genes that affect the uptake and use of glucose-6-phosphate (G-6P). Consistent with an effect on G-6P metabolism, treatment with KSK120 blocked glycogen accumulation. Interestingly, KSK120 did not affect Escherichia coli or the host cell. Thus, 2-pyridone amides may represent a class of drugs that can specifically inhibit C. trachomatis infection.ImportanceChlamydia trachomatis is a bacterial pathogen of humans that causes a common sexually transmitted disease as well as eye infections. It grows only inside cells of its host organism, within a parasitophorous vacuole termed the inclusion. Little is known, however, about what bacterial components and processes are important for C. trachomatis cellular infectivity. Here, by using a visual screen for compounds that affect bacterial distribution within the chlamydial inclusion, we identified the inhibitor KSK120. As hypothesized, the altered bacterial distribution induced by KSK120 correlated with a block in C. trachomatis infectivity. Our data suggest that the compound targets the glucose-6-phosphate (G-6P) metabolism pathway of C. trachomatis, supporting previous indications that G-6P metabolism is critical for C. trachomatis infectivity. Thus, KSK120 may be a useful tool to study chlamydial glucose metabolism and has the potential to be used in the treatment of C. trachomatis infections

Anisotropic and dispersive wave propagation within strain-gradient framework

In this paper anisotropic and dispersive wave propagation within linear strain-gradient elasticity is investigated. This analysis reveals significant features of this extended theory of continuum elasticity. First, and contrarily to classical elasticity, wave propagation in hexagonal (chiral or achiral) lattices becomes anisotropic as the frequency increases. Second, since strain-gradient elasticity is dispersive, group and energy velocities have to be treated as different quantities. These points are first theoretically derived, and then numerically experienced on hexagonal chiral and achiral lattices. The use of a continuum model for the description of the high frequency behavior of these microstructured materials can be of great interest in engineering applications, allowing problems with complex geometries to be more easily treated

How Substitutable is Natural Capital?

One of the recurring themes in the sustainability literature has been the legitimacy of using an economic framework to account for natural resources. This paper examines the potential for substituting between different inputs in the generation of income, where the inputs include natural resources such as land and energy resources. A nested CES production function is used to allow flexibility in the estimated elasticities of substitution. Also, with this specification, natural resources and other inputs are combined in different levels of the function, thus allowing for different levels of substitutability. Institutional and economic indicators are also incorporated in the production function estimated. Results show that the elasticities derived from functions involving land resources were generally around one or greater. Furthermore, changes in trade openness and private sector investment have a statistically significant and direct relationship with income generation. No statistically significant relationship between income and any of the institutional indicators was found.Wealth accounting, Natural resources, Nested CES production function