The role of interbank markets in monetary policy: A model with rationing

This paper analyses the impact of asymmetric information in the interbank market and establishes its crucial role in the microfoundations of the monetary policy transmission mechanism. We show that interbank market imperfections induce an equilibrium with rationing in the credit market. This has two major implications: first, it reconciles the irresponsiveness of business investment to the user cost of capital with the large impact of monetary policy (magnitude effect) and, second, it shows that banks’ liquidity positions condition their reaction to monetary policy (Kashyap and Stein liquidity effect).Banking, Rationing, Monetary Policy

Do we need handshakes to cooperate in buyer-supplier relationships?

Does formal contracting foster cooperation in a buyer-supplier relationship? In line with the literature, we find that a renegotiable contract with relationship-specific joint investments does not make it possible to reach the first-best. However, we show that a renegotiable contract may induce more cooperation than an informal arrangement. This result may help to understand how cooperation emerges in Japanese procurement practices, which typically involve relationship-specific joint investments and renegotiable contracts.Incomplete contracts, relationship-specific investments, cooperation

Combining input-output analysis and micro-simulation to assess the effects of carbon taxation on Spanish households

This paper explores the effects of a tax levied on Spanish energy-related CO2 emissions. After justifying the relevance of carbon taxation in the Spanish context, we consider the introduction of a product (fossil-fuel) tax with a rate obtained through the ‘actual damage cost’ method. Our empirical analysis proceeds in two stages. First, we employ an input-output demand model to calculate the price changes after the introduction of carbon taxation. In a second stage, simulation with Spanish household micro-data for 1994 yields the environmental and economic effects of a Spanish carbon tax. We find a limited short-run reaction to the carbon tax, which hampers its environmental success. The carbon tax burden is, however, significant, with a proportional distribution across households.

Porous-based rheological model for tissue fluidisation

It has been experimentally observed that cells exhibit a fluidisation process when subjected to a transient stretch, with an eventual recovery of the mechanical properties upon removal of the applied deformation. This fluidisation process is characterised by a decrease of the storage modulus and an increase of the phase angle. We propose a rheological model which is able to reproduce this combined mechanical response. The model is described in the context of continua and adapted to a cell-centred particle system that simulates cell–cell interactions. Mechanical equilibrium is coupled with two evolution laws: (i) one for the reference configuration, and (ii) another for the porosity or polymer density. The first law depends on the actual strain of the tissue, while the second assumes different remodelling rates during porosity increase and decrease. The theory is implemented on a particle based model and tested on a stretching experiment. The numerical results agree with the experimental measurements for different stretching magnitudes.Peer ReviewedPostprint (author's final draft

Iceberg transport technologies in spatial competition. Hotelling reborn

Transport costs in address models of differentiation are usually modeled as separable of the consumption commodity and with a parametric price. However, there are many sectors in an economy where such modeling is not satisfactory either because transportation is supplied under oligopolistic conditions or because there is a difference (loss) between the amount delivered at the point of production and the amount received at the point of consumption. This paper is a first attempt to tackle these issues proposing to study competition in spatial models using an iceberg-like transport cost technology allowing for concave and convex melting functions.Spatial Competition, Iceberg transport costs

Thermal curing of an epoxy-anhydride system modified with hyperbranched poly(ethylene imine)s with different terminal groups

New hyperbranched polymers (HBP) have been synthesized by reaction of a poly(ethylene imine) with phenyl and t-butyl isocyanates. These HBPs have been characterized by 1H-NMR (nuclear magnetic resonance of hydrogen) and Fourier transform infrared spectroscopy. Their influence on the curing and properties of epoxy-anhydride thermosets has been studied by different techniques: differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermogravimetry (TG). The curing kinetics has been studied with DSC. Integral isoconversional method and the S ¿ esta´k–Berggren model have been used to determine the activation energy and the frequency factor. The kinetic parameters are very similar for all the studied systems at the middle stage of the process, but changes are observed at the beginning and at the end of the process when these modifiers are used. The HBPs reduce the glass transition temperature of the cured materials. In addition, from the DMA analysis it can be seen that the HBP modifier obtained from phenyl isocyanate hardly changes the storage modulus, but the obtained ones from t-butyl isocyanate decrease it. TG analysis reveals a decrease in the onset temperature of the degradation process upon addition of the HBPs.Postprint (author's final draft

Curing of off-stoichiometric amine–epoxy thermosets

The kinetics of the epoxy–amine polycondensation and the epoxy homopolymerization in off-stoichiometric epoxy/amine formulations with excess of epoxy groups, and in the presence of an anionic initiator have been investigated. Diglycidyl ether of bisphenol A (DGEBA) and diethylenetriamine (DETA) have been used as epoxy and amine reagents, respectively, and 2-methylimidazole (2MI) has been used as anionic initiator. This study has been carried out using a differential scanning calorimeter (DSC). The thermal–mechanical properties of the partially cured and fully cured materials with and without initiator have been determined by DSC and dynamic-mechanical analysis. First, off-stoichiometric DGEBA/DETA mixtures with excess of DGEBA, with and without 2MI, have been reacted isothermally at low temperatures, where only the epoxy–amine condensation takes place, because the epoxy homopolymerization has a very low curing rate. Afterward, samples containing 2MI have been heated at different heating rates to study the homopolymerization process of the epoxy excess. The kinetics of both processes have been analyzed with an isoconversional method to determine the activation energy, and the Šesták–Berggren equation has been applied to determine the frequency factor and the orders of reaction. In the isothermal curing, amine–epoxy condensation, the activation energy and the frequency factor decrease with increasing degree of conversion, but in the homopolymerization process, both magnitudes increase with the degree of conversion. Results show that the dual-curing character of off-stoichiometric DGEBA/DETA thermosets with 2MI as anionic initiator renders them suitable for multistage curing processes in which the degree of cure and material properties in the intermediate stage can be controlled easily and final material properties can be enhanced.Postprint (author's final draft