Macroeconomic Stabilization of Economies in Transition: Recent Experiences, Preliminary Results and Some Lessons

This Working Paper is a summary of the Workshop on "Macroeconomic Stabilization of Economies in Transition" held in Prague, Czech Republic on 22-24 April 1993. The workshop was organized by the Economic Transition and Integration Project of IIASA and the Institute for Economic Policy affiliated to the Ministry of Economy of the Czech Republic. The purpose of the workshop was to assemble responsible policy makers, interested scholars from Central and Eastern European countries, as well as western experts to thoroughly discuss the accumulated experience with macroeconomic stabilization during economic reforms in Albania, Bulgaria, Croatia, the Czech and Slovak Republics (the former CSFR as well), Hungary, Poland, Romania, Russia, and the Ukraine. Those who presented papers and those who commented on them aimed at drawing attention to problems that are now explicit and pressing in countries which started with reforms sooner and are very likely to emerge in countries that started later. The organizers of the workshop firmly believed that the dissemination of experience from the more advanced reform countries could contribute to a better understanding of burdensome stabilization tasks and to a future improvement and refinement of stabilization policies and tools. Undoubtedly, a smoother and more successful transition will benefit not only the less advanced countries but to the region as a whole. In retrospect we may now conclude that a good basis for a fruitful exchange of views and stimulating discussions was provided at the workshop

Stabilization Policies at Crossroads? An Interim Report From Central and Eastern Europe

The papers in this volume were written by experts from Central and Eastern Europe and constitute the core of the material presented at the international workshop on "Macroeconomic Stabilization of Economies in Transition" held in Prague, Czech Republic from 22 to 24 April 1993. The purpose of the workshop was to assemble policy-makers and interested scholars from Central and Eastern European countries, as well as western experts to thoroughly discuss the accumulated experience with macroeconomic stabilization during economic reforms in Albania, Bulgaria, Croatia, former Czechoslovakia and its successors the Czech and Slovak Republics, Hungary, Poland, Romania, Russia, and Ukraine. Those who presented papers and those who commented drew attention to problems now explicit and urgent in countries which pioneered reform to convert from communist central planning to a pluralist market system. The late-comers to the transition process are very likely to face similar complications and dilemmas. Organizers of the workshop firmly believed that dissemination of experience from more rapidly advancing reform countries could contribute to a better understanding of burdensome stabilization tasks and to a future improvement and refinement of stabilization policies and tools, particularly for the benefit of the transitional laggards. The results of the workshop inferred that the stabilization of a post-socialist economy is a difficult but attainable goal. The character of stabilization policies underwent many modifications and adjustments. Their initial stringency was abandoned and replaced by more adaptive policies in some countries. The workshop participants generally also agreed that regardless of the approach utilized to implement the stabilization effort (shock versus gradual approach), countries face similar problems after the stabilization phase: they comprise long-term and painful restructuring of industries; budget imbalances; extensive restructuring of the public sector; enlarging the scope of currency convertibility; time-consuming privatization; and so forth. Recognition of the dynamic changes in the recent past, as well as the decisions facing policy-makers in post-communist countries in contemplating how to proceed where from each unique position already attained, guided us to choose "Stabilization Policies at Crossroads?" as the title of this volume

Evidence for alternative quaternary structure in a bacterial Type III secretion system chaperone

<p>Abstract</p> <p>Background</p> <p>Type III secretion systems are a common virulence mechanism in many Gram-negative bacterial pathogens. These systems use a nanomachine resembling a molecular needle and syringe to provide an energized conduit for the translocation of effector proteins from the bacterial cytoplasm to the host cell cytoplasm for the benefit of the pathogen. Prior to translocation specialized chaperones maintain proper effector protein conformation. The class II chaperone, Invasion plasmid gene (Ipg) C, stabilizes two pore forming translocator proteins. IpgC exists as a functional dimer to facilitate the mutually exclusive binding of both translocators.</p> <p>Results</p> <p>In this study, we present the 3.3 Å crystal structure of an amino-terminally truncated form (residues 10-155, denoted IpgC^10-155) of the class II chaperone IpgC from <it>Shigella flexneri</it>. Our structure demonstrates an alternative quaternary arrangement to that previously described for a carboxy-terminally truncated variant of IpgC (IpgC^1-151). Specifically, we observe a rotationally-symmetric "head-to- head" dimerization interface that is far more similar to that previously described for SycD from <it>Yersinia enterocolitica </it>than to IpgC^1-151. The IpgC structure presented here displays major differences in the amino terminal region, where extended coil-like structures are seen, as opposed to the short, ordered alpha helices and asymmetric dimerization interface seen within IpgC^1-151. Despite these differences, however, both modes of dimerization support chaperone activity, as judged by a copurification assay with a recombinant form of the translocator protein, IpaB.</p> <p>Conclusions</p> <p>From primary to quaternary structure, these results presented here suggest that a symmetric dimerization interface is conserved across bacterial class II chaperones. In light of previous data which have described the structure and function of asymmetric dimerization, our results raise the possibility that class II chaperones may transition between asymmetric and symmetric dimers in response to changes in either biochemical modifications (e.g. proteolytic cleavage) or other biological cues. Such transitions may contribute to the broad range of protein-protein interactions and functions attributed to class II chaperones.</p

A well-defined diamine from lignin depolymerization mixtures for constructing bio-based polybenzoxazines

The demand for high-performance materials is increasing, and most of these materials are petrol based. Therefore, the development of highly efficient and selective catalytic methods that allow access to industrially relevant polymer building blocks from complex biomass depolymerization mixtures is essential. Here, we report on a robust catalytic strategy to obtain the industrially relevant 4,4′-methylenebiscyclohexanamine (MBCA) from lignin oxidation mixtures and its use for constructing fully bio-based polybenzoxazines. The strategy consists of two challenging catalytic steps: 1) the funneling of lignin-derived bisphenol mixtures into 4,4′-methylenebiscyclohexanol (MBC) and 2) the highly selective amination of MBC with ammonia to obtain MBCA. The renewable polybenzoxazines were prepared from MBCA and phenolic lignin platform chemicals. The most promising, cured poly (S-MBCA), shows high glass transition temperature Tg of 315°C, outstanding thermal stability (T10% = 400°C), and good storage modulus (E′25°C = 3.8 GPa), which is competitive with commercial resins

Can We Delineate Potential Output for an Economy in Transition? Search for a Benchmark

This paper was stimulated by a striking discrepancy which exists between the frequency with which the concept of potential output is dealt with in every basic macroeconomic textbook and nearly complete absence of any comprehension of what might have happened to potential output in economies in transition. Although the search for this macroeconomic pivotal point may look like solving an intellectual puzzle, the real challenge lies in implications of changes in potential output for effective policy-making during the transformation period. This paper points out some weaknesses of applying standard macroeconomic concepts (like Okun's law) and illuminates the necessity of using indirect and mezzo-economic approaches. Despite the difficulty of making a new definition of potential output operational, this paper suggests the usefulness of introducing a kind of transformation bridge which should methodologically facilitate understanding the concept of potential output when moving from a centrally planned economy to a market one

Feather growth rate and mass in nearctic passerines with variablemigratory behavior and molt pattern

Bird species vary greatly in the duration of their annual complete feather molt. However, such variation is not well documented in birds from many biogeographic areas, which restricts our understanding of the diversification of molt strategies. Recent research has revealed that molt duration can be estimated in passerines from ptilochronology-based measurements of the growth rate of their tail feathers. We used this approach to explore how molt duration varied in 98 Nearctic species that have different migratory strategies and molt patterns. As previously documented for Palearctic species, migration was associated with a shortening of molt duration among species that molted during summer on their breeding range. However, molts of winter-molting migratory species were as long as those of summer-molting sedentary species, which suggests that winter molt also allows Nearctic migrants to avoid the temporal constraints experienced during summer. Our results also suggest that migratory species that undergo a stopover molt within the Mexican monsoon region have the shortest molt duration among all Nearctic passerines. Interestingly, and contrary to expectations from a potential tradeoff between molt duration and feather quality, observed variation in feather growth rate was positively correlated with differences in tail feather mass, which may be caused by differences among groups in the availability of resources for molting. We encourage the use of similar approaches to study the variation in molt duration in other geographic areas where knowledge of the evolution of molt is limited.

Fully lignocellulose-based PET analogues for the circular economy

Polyethylene terephthalate is one of the most abundantly used polymers, but also a significant pollutant in oceans. Due to growing environmental concerns, polyethylene terephthalate alternatives are highly sought after. Here we present readily recyclable polyethylene terephthalate analogues, made entirely from woody biomass. Central to the concept is a two-step noble metal free catalytic sequence (Cu20-PMO catalyzed reductive catalytic fractionation and Raney Ni mediated catalytic funneling) that allows for obtaining a single aliphatic diol 4-(3-hydroxypropyl) cyclohexan-1-ol in high isolated yield (11.7 wt% on lignin basis), as well as other product streams that are converted to fuels, achieving a total carbon yield of 29.5%. The diol 4-(3-hydroxypropyl) cyclohexan-1-ol is co-polymerized with methyl esters of terephthalic acid and furan dicarboxylic acid, both of which can be derived from the cellulose residues, to obtain polyesters with competitive Mw and thermal properties (Tg of 70–90 °C). The polymers show excellent chemical recyclability in methanol and are thus promising candidates for the circular economy.</p

A differential method for bounding the ground state energy

For a wide class of Hamiltonians, a novel method to obtain lower and upper bounds for the lowest energy is presented. Unlike perturbative or variational techniques, this method does not involve the computation of any integral (a normalisation factor or a matrix element). It just requires the determination of the absolute minimum and maximum in the whole configuration space of the local energy associated with a normalisable trial function (the calculation of the norm is not needed). After a general introduction, the method is applied to three non-integrable systems: the asymmetric annular billiard, the many-body spinless Coulombian problem, the hydrogen atom in a constant and uniform magnetic field. Being more sensitive than the variational methods to any local perturbation of the trial function, this method can used to systematically improve the energy bounds with a local skilled analysis; an algorithm relying on this method can therefore be constructed and an explicit example for a one-dimensional problem is given.Comment: Accepted for publication in Journal of Physics