The Provision of Social Benefits in State Owned

We use evidence from a survey of approximately 200 Polish state-owned, privatized, and de novo private manufacturing firms to investigate the nature and scope of enterprises-level provision of social benefits, and in particular how enterprise-level social provision is changing with transition, privatization and the emergence of the new private sector. We find that social provision remains surprisingly widespread, and has not been greatly reduced in either the state-owned or the privatized sectors. De novo private firms offer a substantially smaller but still significant range of social provision aside from ownership form are firm sized and employee power ( the latter are not explicitly via the union structure), both of which are associated with higher levels of social provision. Money wages and the provision of social benefits appear to be complementary rather than substitutes. Assets used for the provision of social benefits are concentrated in state-owned firms, but there is relatively little social asset disposal; the de novo private sector is expanding the range of social benefits offered but is not investing significantly in social assets. Social provision has been declining in state-owned firms, less so in privatized firms, and increasingly (modestly) in new private firms. On average the declines determinants of the pace of change aside from ownership form are the size of the firm and its profitability, both of which are associated with increases or slower declines in social provision, in the case of the state-owned sector, provision also declines more slowly when they tax-based income policy (the "popwiek") binds.

Enterprise Adjustment in Poland: Evidence from a Survey of 200 Private

This paper reports the main findings from a survey of some 200 Polish firms carried out at the end of 1993. The central focus is on the relationship between different emerging forms of ownership and the extent and nature of enterprise level adjustments taking place. Four broad categories of enterprises that distinguish the main ownership forms that characterize Polish industry were included in the survey: (a) traditional state-owned enterprises, (b) corporatized state-owned enterprises that have been converted into joint stock companies but whose shares are now owned by the State Treasury; (c) former state-owned firms that have been privatized; and (d) privately-owned firms which were established de novo. Some of the main findings from the survey are as follows. Growth and investment in 1993 were widely diffused through the economy, but rather more concentrated in the private sector and especially in de novo private firms, while financial distress as revealed by low profit margins was concentrated in the state-owned sector. The survey suggests that all firms in Poland have experienced a considerable increase in competition, and have faced the need radically to restructure their patterns of input purchases and marketing strategy. In general, de novo private firms have led the way, and changes have been fewer and less deep in the state-owned sector. Developments on the labor side in our sample are rather modest, and to be heavily oriented to satisfy the preferences of insiders, especially workers. Overmanning remains rife in both the state-owned and privatized sector, and differences between the two groups of firms in wage determination appear to stem more from the operation of the excess wage tax than from differences in motivation. Behavior in the de novo private firms is, however, clearly different, with a concern to hire not fire, and with lower employee influence. With respect to finance, we find that privatized and especially de novo private firms are financially relatively healthy, with higher profits and fewer bad debts than the state-owned firms. Although almost half of private sector firms hold no bank debt, bank credit is flowing fastest to these firms and in general they report the fewest problems in servicing it. Overdue trade credit is common among all ownership groups but more so among state firms; however, the flow problem is not serious, and volumes of total and overdue trade credit are comparable to West European levels. The main method by which severely financially-distressed firms, nearly all of which are state-owned, finance their losses is by running up tax arrears; financing by banks and by trade credit is much less significant.

The effect of ownership and competitive pressure on firm performance in transition countries. Micro evidence from Bulgaria, Romania and Poland.

Country; Firm performance; Ownership; Performance;

Information Horizons in Networks

We investigate and quantify the interplay between topology and ability to send specific signals in complex networks. We find that in a majority of investigated real-world networks the ability to communicate is favored by the network topology on small distances, but disfavored at larger distances. We further discuss how the ability to locate specific nodes can be improved if information associated to the overall traffic in the network is available.Comment: Submitted top PR

pH-dependent mechanism of nitric oxide release in nitrophorins 2 and 4

Nitrophorins are NO carrier proteins that transport and release NO through a pH-dependent conformational change. They bind NO tightly in a low pH environment and release it in a higher pH environment. Experimental evidence shows that the increase in the NO dissociation equilibrium constant, K d, is due mainly to an increase in the NO release rate. Structural and kinetic data strongly suggest that NPs control NO escape by modulating its migration from the active site to the solvent through a pH-dependent conformational change. NP2 and NP4 are two representative proteins of the family displaying a 39% overall sequence identity, and interestingly, NP2 releases NO slower than NP4. The proposal that NPs' NO release relies mainly on the NO escape rate makes NPs a very peculiar case among typical heme proteins. The connection between the pH-dependent conformational change and ligand release mechanism is not fully understood and the structural basis for the pH induced structural transition and the different NO release patterns in NPs are unresolved, yet interesting issues. In this work, we have used state of the art molecular dynamics simulations to study the NO escape process in NP2 and NP4 in both the low and high pH states. Our results show that both NPs modulate NO release by switching between a "closed" conformation in a low pH environment and an "open" conformation at higher pH. In both proteins, the change is caused by the differential protonation of a common residue Asp30 in NP4 and Asp29 in NP2, and the NO escape route is conserved. Finally, our results show that, in NP2, the conformational change to the "open" conformation is smaller than that for NP4 which results in a higher barrier for NO release.Fil: Swails, Jason M.. University of Florida; Estados UnidosFil: Meng, Yilin. University of Florida; Estados UnidosFil: Walker, F. Ann. University of Arizona; Estados UnidosFil: Marti, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Estrin, Dario Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Roitberg, Adrián. University of Florida; Estados Unido

The extraordinary catalytic ability of peroxiredoxins: a combined experimental and QM/MM study on the fast thiol oxidation step

Peroxiredoxins (Prxs) catalyze the reduction of peroxides, a process of key relevance in a variety of cellular processes. The first step in the catalytic cycle of all Prxs is the oxidation of a cysteine residue to sulfenic acid, which occurs 103–107 times faster than in free cysteine. We present an experimental kinetics and hybrid QM/MM investigation to explore the reaction of Prxs with H2O2 using alkyl hydroperoxide reductase E from Mycobacterium tuberculosis as a Prx model. We report for the first time the thermodynamic activation parameters of H2O2 reduction using Prx, which show that protein significantly lowers the activation enthalpy, with an unfavourable entropic effect, compared to the uncatalyzed reaction. The QM/MM simulations show that the remarkable catalytic effects responsible for the fast H2O2 reduction in Prxs are mainly due to an active-site arrangement, which establishes a complex hydrogen bond network activating both reactive species.Fil: Zeida Camacho, Ari Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; ArgentinaFil: Reyes, Aníbal M.. Universidad de la República; UruguayFil: González Lebrero, Mariano Camilo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica; ArgentinaFil: Radi Isola, Rafael. Universidad de la República; UruguayFil: Trujillo, Madia. Universidad de la República; UruguayFil: Estrin, Dario Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin