Chenggang Xu

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When should a government provide a service in-house, and when should it contract out provision? We develop a model in which the provider can invest in improving the quality of service or reducing cost. If contracts are incomplete, the private provider has a stronger incentive to engage in both quality improvement and cost reduction than a government(More)
C economic reforms, which have been in flux for three decades, have more than doubled China’s economic growth, from an average of 4.4 percent annually before 1978 to an average of 9.5 percent after 1978. Even more impressively, the contribution of TFP to the growth has increased from 11 percent before 1978 to more than 40 percent afterwards (Dwight H.(More)
Aghion, Masahiko Aoki, Patrick Bolton, Avner Grief, Athar Hussain, Carla Krüger, Nicholas Lardy, John Litwack, Eric Maskin, John McMillan, Paul Milgrom, Dwight Perkins, Louis Putterman, Gerard Roland, Anna Seleny, Barry Weingast, Martin Weitzman, Jinglian Wu, and an anonymous referee for helpful discussions and comments. Qian's research is sponsored by the(More)
This paper studies incentives and loss of control in a hierarchy model which combines and generalizes the models of Williamson, Calvo-Wellisz and Keren-Levhari. In our model of the hierarchy, the levels of effort from managers and workers, the wage scales, the span of control and, in particular, the total number of tiers are all endogenous. Using optimal(More)
Jump-starting stock markets in transition economies has proved difficult. These countries lack effective legal governance structures and face severe information problems. Yet not all financial markets failed because of adverse conditions. Using China’s initial stock market development as a case study, this article suggests that administrative governance can(More)
In our previous study, an ompP2 mutant of a Haemophilus parasuis SC096 strain showed sensitivity to serum bactericidal activity. In this study, we inactivated two gal genes, galU and galE, and these mutants were found to be serum sensitive to porcine sera. Furthermore, the galE mutant exhibited greater sensitivity than the galU mutant in serum sensitivity(More)
Cytolethal distending toxin (CDT) is proposed to be an important virulence determinant of many pathogens. Although two cdt gene cluster loci have been identified in Haemophilus parasuis strain SH0165, the characteristics of CDTs associated with pathogenesis remain unclear. In this study, three CDT-deficient mutants, cdt-1, cdt-2 and the double-knockout(More)
In Gram-negative bacteria, porins not only contribute to bacterial homeostasis, but also are involved in adherence to and invasion of host cells. Haemophilus parasuis outer membrane protein P2 (OmpP2), a member of the porin family, is an important surface protein involved in serum resistance. To further determine the features of OmpP2, the ability of ompP2(More)
Haemophilus parasuis is the causative agent of Glässer's disease. To investigate the role of lipooligosaccharide (LOS) in H. parasuis infection, ΔopsX, ΔrfaF and ΔwaaQ mutants defective in expressing opsX, rfaF and waaQ heptosyltransferases were constructed by transformation. Compared to the wild-type SC096 strain, the ΔopsX and ΔrfaF mutants, but not the(More)
BACKGROUND Many bacteria efficiently degrade lignocellulose yet the underpinning genome-wide metabolic and regulatory networks remain elusive. Here we revealed the "cellulose degradome" for the model mesophilic cellulolytic bacterium Clostridium cellulolyticum ATCC 35319, via an integrated analysis of its complete genome, its transcriptomes under glucose,(More)