Votes and Vetoes: The Political Determinants of Commercial Openness

Societal theories of trade policy stress the importance of domestic interest groups, whereas statist theories focus on the effects of domestic institutions. Debates over the relative merits of these approaches have been fierce, but little systematic empirical research has been brought to bear on the relative merits of these theories. In this paper, we argue that, while societal and statist factors are generally regarded as having independent and competing effects, it is more fruitful to view the influence of each type of factor as conditional on the other. As societal explanations contend, deteriorating macroeconomic conditions are a potent source of protectionist pressures. The extent to which such conditions reduce commercial openness, however, depends centrally on the domestic institutions through which societal pressures must filter to influence policy. Two institutional features stand out. First, in states marked by greater fragmentation and more “veto points,” it is harder to change existing policies because any number of actors can block such change. Consequently, we expect the effects of macroeconomic conditions on trade policy to be weaker in fragmented states than in those characterized by a highly centralized national government. Second, we expect both fragmentation and the societal pressures stemming from the economy to have a more potent impact on trade policy in democracies than in other regimes, since the electoral constraints facing democratic leaders force them to respond to demands made by key segments of society. The results of our statistical tests covering more than one hundred countries during the period from 1980 to 2000 strongly support these arguments.http://deepblue.lib.umich.edu/bitstream/2027.42/40098/3/wp712.pd

Votes and Vetoes: The Political Determinants of Commercial Openness

Societal theories of trade policy stress the importance of domestic interest groups, whereas statist theories focus on the effects of domestic institutions. Debates over the relative merits of these approaches have been fierce, but little systematic empirical research has been brought to bear on the relative merits of these theories. In this paper, we argue that, while societal and statist factors are generally regarded as having independent and competing effects, it is more fruitful to view the influence of each type of factor as conditional on the other. As societal explanations contend, deteriorating macroeconomic conditions are a potent source of protectionist pressures. The extent to which such conditions reduce commercial openness, however, depends centrally on the domestic institutions through which societal pressures must filter to influence policy. Two institutional features stand out. First, in states marked by greater fragmentation and more “veto points,” it is harder to change existing policies because any number of actors can block such change. Consequently, we expect the effects of macroeconomic conditions on trade policy to be weaker in fragmented states than in those characterized by a highly centralized national government. Second, we expect both fragmentation and the societal pressures stemming from the economy to have a more potent impact on trade policy in democracies than in other regimes, since the electoral constraints facing democratic leaders force them to respond to demands made by key segments of society. The results of our statistical tests covering more than one hundred countries during the period from 1980 to 2000 strongly support these arguments.Protectionism, openness, veto players, veto points, positive political theory, unemployment, trade

Support for Free Trade: Self-Interest, Sociotropic Politics, and Out-Group Anxiety

Although it is widely acknowledged that an understanding of mass attitudes about trade is crucial to the political economy of foreign commerce, only a handful of studies have addressed this topic. These studies have focused largely on testing two models, both of which emphasize that trade preferences are shaped by how trade affects an individual\u27s income. The factor endowments or Heckscher-Ohlin model posits that these preferences are affected primarily by a person\u27s skills. The specific factors or Ricardo-Viner model posits that trade preferences depend on the industry in which a person works. We find little support for either of these models using two representative national surveys of Americans. The only potential exception involves the effects of education. Initial tests indicate that educational attainment and support for open trade are directly related, which is often interpreted as support for the Heckscher-Ohlin model. However, further analysis reveals that education\u27s effects are less representative of skill than of individuals\u27 anxieties about involvement with out-groups in their own country and beyond. Furthermore, we find strong evidence that trade attitudes are guided less by material self-interest than by perceptions of how the U.S. economy as a whole is affected by trade

Votes and Vetoes: The Political Determinants of Commercial Openness

Some theories of foreign economic policy stress the importance of domestic interest groups, whereas others focus on the effects of domestic institutions. Debates between advocates of these approaches are longstanding, but little systematic empirical research has been brought to bear on the relative merits of these theories. We argue that while interest group demands and institutions are often regarded as having independent and competing effects, it is more fruitful to view the influence of each type of factor as conditional on the other. As explanations emphasizing societal interests contend, deteriorating macroeconomic conditions are a potent source of protectionist sentiment. The extent to which such conditions reduce commercial openness, however, depends centrally on a country\u27s political institutions, especially the number of veto points in a country\u27s policy-making structure and its regime type. We expect the effects of macroeconomic conditions on trade policy to become weaker as the number of veto points increases. We also expect both veto points and the societal pressures stemming from the economy to have a more potent impact on trade policy in democracies than in other regimes. The results of our statistical tests covering almost 60 countries during the period from 1980 to 2000 strongly support these arguments

Sulfonated copolymers as heparin-mimicking stabilizer of fibroblast growth factor : size, architecture, and monomer distribution effects

Fibroblast growth factors (FGF) are involved in a wide range of biological processes such as cell proliferation and differentiation. In living organisms, the binding of FGF to its receptors are mediated through electrostatic interactions between FGF and naturally occurring heparin. Despite its prevalent use in medicine, heparin carries notable limitations, namely; its extraction from natural sources (expensive, low yield and extensive purification), viral contamination, and batch-to-batch heterogeneity. In this work a range of synthetic homopolymers and copolymers of sodium 2-acrylamido-2-methylpropane sulfonate (AMPS®) were evaluated as potential FGF stabilisers. This was studied by measuring the proliferation of BaF3-FR1c cells, as a model assay, and the results will be compared with the natural stabilisation and activation of FGF by heparin. This study explores the structure-activity relationship of these polysulfonated polymers with a focus on the effect of molecular weight, co-monomer type, charge dispersion and polymer architecture on protein stabilisation

Mucus penetrating properties of soft, distensible lipid nanocapsules

Designing nanomaterials to release their drug pay-load upon exposure to an exogenous trigger can help to direct drug delivery, but how the triggered release, which often modifies the nanomaterial properties, influences the biological fate of these systems is currently unknown. The aim of this study was to investigate how the triggered drug release from PEG coated, soft, 50 nm distensible lipid nanocapsules (LNC) influenced their diffusion across a mucus barrier. The translocation speed of the non-triggered LNC across a 35 µm thick purified gastric mucin (PGM) barrier was 3 times faster (30.08 ± 2.49 x 10-10 cm2 s-1) compared to equivalent-sized negatively charged polystyrene particles (9.87 ± 0.61 x 10-10 cm2 s-1, p 0.05) in a static mucus barrier, but when shear was applied to the barrier the distended LNCs diffused more slowly (3.97 ± 1.38 x 10-8 cm2s-1, p < 0.05) compared to the non-distended materials (4.94 ± 0.04 x 10-8 cm2s-1). This data suggested the rapid mucus penetration of the distended LNCs, despite their increased size, was a consequence of their capacity to take a less tortious path through the barrier, i.e., they experienced less steric hinderance, compared to the non-distended LNC

Probing the dynamic nature of self-assembling cyclic peptide-polymer nanotubes in solution and in mammalian cells

Self-assembling cyclic peptide–polymer nanotubes have emerged as a fascinating supramolecular system, well suited for a diverse range of biomedical applications. Due to their well-defined diameter, tunable peptide anatomy, and ability to disassemble in situ, they have been investigated as promising materials for numerous applications including biosensors, antimicrobials, and drug delivery. Despite this continuous effort, the underlying mechanisms of assembly and disassembly are still not fully understood. In particular, the exchange of units between individual assembled nanotubes has been overlooked so far, despite its knowledge being essential for understanding their behavior in different environments. To investigate the dynamic nature of these systems, cyclic peptide–polymer nanotubes are synthesized, conjugated with complementary dyes, which undergo a Förster resonance energy transfer (FRET) in close proximity. Model conjugates enable to demonstrate not only that their self-assembly is highly dynamic and not kinetically trapped, but also that the self-assembly of the conjugates is strongly influenced by both solvent and concentration. Additionally, the versatility of the FRET system allows studying the dynamic exchange of these systems in mammalian cells in vitro using confocal microscopy, demonstrating the exchange of subunits between assembled nanotubes in the highly complex environment of a cell

Supramolecular hybrid structures and gels from host–guest interactions between α-cyclodextrin and PEGylated organosilica nanoparticles

Polypseudorotaxanes are polymer chains threaded by molecular rings that are free to unthread; these “pearl-necklace” can self-assemble further, leading to higher-order supramolecular structures with interesting functionalities. In this work, the complexation between α-cyclodextrin (α-CD), a cyclic oligosaccharide of glucopyranose units, and poly(ethylene glycol) (PEG) grafted to silica nanoparticles was studied. The threading of α-CD onto the polymeric chains leads to their aggregation into bundles, followed by either the precipitation of the inclusion complex or the formation of a gel phase, in which silica nanoparticles are incorporated. The kinetics of threading, followed by turbidimetry, revealed a dependence of the rate of complexation on the following parameters: the concentration of α-CD, temperature, PEG length (750, 4000, and 5000 g mol–1), whether the polymer is grafted or free in solution, and the density of grafting. Complexation is slower, and temperature has a higher impact on PEG grafted on silica nanoparticles compared to PEG free in solution. Thermodynamic parameters extracted from the transition-state theory showed that inclusion complex formation is favored with grafted PEG compared to free PEG and establishes a ratio of complexation of five to six ethylene oxide units per cyclodextrin. The complexation yields, determined by gravimetry, revealed that much higher yields are obtained with longer chains and higher grafting density. Thermogravimetric analysis and Fourier transform infrared spectroscopy on the inclusion complex corroborate the number of macrocycles threaded on the chains. A sol–gel transition was observed with the longer PEG chain (5k) at specific mixing ratios; oscillatory shear rheology measurements confirmed a highly solid-like behavior, with an elastic modulus G′ of up to 25 kPa, higher than that in the absence of silica. These results thus provide the key parameters dictating inclusion complex formation between cyclodextrin and PEG covalently attached to colloidal silica and demonstrate a facile route toward soft nanoparticle gels based on host–guest interactions

Structure and characterisation of hydroxyethylcellulose–silica nanoparticles

Functionalising nanoparticles with polymers has gained much interest in recent years, as it aids colloidal stability and manipulation of surface properties. Here, polymer-coated thiolated silica nanoparticles were synthesised by self-condensation of 3-mercaptopropyltrimethoxysilane in the presence of hydroxyethylcellulose. These nanoparticles were characterised by dynamic light scattering, small angle neutron scattering, Nanoparticle Tracking Analysis, Raman spectroscopy, FT-IR spectroscopy, thermogravimetric analysis, Ellman's assay, transmission electron microscopy and cryo-transmission electron microscopy. It was found that increasing the amount of hydroxyethylcellulose in the reaction mixture increased the nanoparticle size and reduced the number of thiol groups on their surface. Additionally, by utilising small angle neutron scattering and dynamic light scattering, it was demonstrated that higher concentrations of polymer in the reaction mixture (0.5–2% w/v) resulted in the formation of aggregates, whereby several silica nanoparticles are bridged together with macromolecules of hydroxyethylcellulose. A correlation was identified between the aggregate size and number of particles per aggregate based on size discrepancies observed between DLS and SANS measurements. This information makes it possible to control the size of aggregates during a simple one-pot synthesis; a prospect highly desirable in the design of potential drug delivery systems

Dual self-assembly of supramolecular peptide nanotubes to provide stabilisation in water

Self-assembling peptides have the ability to spontaneously aggregate into large ordered structures. The reversibility of the peptide hydrogen bonded supramolecular assembly make them tunable to a host of different applications, although it leaves them highly dynamic and prone to disassembly at the low concentration needed for biological applications. Here we demonstrate that a secondary hydrophobic interaction, near the peptide core, can stabilise the highly dynamic peptide bonds, without losing the vital solubility of the systems in aqueous conditions. This hierarchical self-assembly process can be used to stabilise a range of different β-sheet hydrogen bonded architectures