4,334 research outputs found

    The Beltway Network: A Network Analysis of Lobbyists\u27 Donations to Members of Congress

    Get PDF
    This paper develops a network approach to lobbying. We posit that the building blocks of the lobbying game are relationships, with lobbyists and legislators benefitting from bonds based on familiarity and mutual interest. Using data on contributions from lobbyists to legislators in the 2006 electoral cycle, we identify key dimensions of this network. We find that legislators are more likely to receive donations from the same lobbyists if they are from the same party (in the Senate), state, or committee; if they are both vulnerable in the next election; and the number of common donors increases the more agreement there is in the voting record of a pair of legislators

    The Social Utility of Informal Institutions: Caucuses as Networks in the 110th United States House of Representatives

    Get PDF
    This paper challenges the existing state-of-knowledge about legislative caucuses by arguing that the caucus system reflects and reinforces formal organizing institutions, such as parties and committees, rather than counterbalancing them. We argue that legislators engage in the caucus system in order to maximize the social utility of their relationships. Using a social network framework, we develop and test hypotheses that seek to ascertain the types of legislators that benefit most from the caucus network. We collect data on the complete population of caucuses and their members from the first session of the 110th U.S. House of Representatives and conduct social network and regression analyses to find evidence that the caucus system both supports the hierarchical structure of the formal leadership institutions and offers a meaningful way for all members to establish and maintain relationships with their colleagues

    Role of metal-dependent regulation of ESX-3 secretion in intracellular survival of Mycobacterium tuberculosis

    Get PDF
    More people die every year from Mycobacterium tuberculosis infection than from infection by any other bacterial pathogen. Type VII secretion systems (T7SS) are used by both environmental and pathogenic mycobacteria to secrete proteins across their complex cell envelope. In the nonpathogen Mycobacterium smegmatis, the ESX-1 T7SS plays a role in conjugation, and the ESX-3 T7SS is involved in metal homeostasis. In M. tuberculosis, these secretion systems have taken on roles in virulence, and they also are targets of the host immune response. ESX-3 secretes a heterodimer composed of EsxG (TB9.8) and EsxH (TB10.4), which impairs phagosome maturation in macrophages and is essential for virulence in mice. Given the importance of EsxG and EsxH during infection, we examined their regulation. With M. tuberculosis, the secretion of EsxG and EsxH was regulated in response to iron and zinc, in accordance with the previously described transcriptional response of the esx-3 locus to these metals. While iron regulated the esx-3 expression in both M. tuberculosis and M. smegmatis, there is a significant difference in the dynamics of this regulation. In M. smegmatis, the esx-3 locus behaved like other iron-regulated genes such as mbtB. In M. tuberculosis, both iron and zinc modestly repressed esx-3 expression. Diminished secretion of EsxG and EsxH in response to these metals altered the interaction of M. tuberculosis with macrophages, leading to impaired intracellular M. tuberculosis survival. Our findings detail the regulatory differences of esx-3 in M. tuberculosis and M. smegmatis and demonstrate the importance of metal-dependent regulation of ESX-3 for virulence in M. tuberculosis

    Multiplex Legislative Networks and the Power of Caucuses to Alleviate Partisan Polarization

    Get PDF
    Congress has been increasingly criticized as a broken, gridlocked, polarized, ineffective institution. In this paper we seek to explore the consequences of polarization and whether legislators take steps to alleviate them. We hypothesize that participation in the voluntary, bipartisan, caucus system provides opportunities for legislators to build cross-partisan relationships and profit from shared information, which can alleviate some of the negative effects of polarization. We operationalize polarization using dyadic covoting and show that legislators are more likely to covote if they share more caucus connections, controlling for a variety of factors that predict voting. The data in this analysis spans 9 congresses (1993-2010) and includes multiple connections between legislators
    corecore