1,113 research outputs found

    Complex of primary and secondary parasitoids (Hymenoptera: Encyrtidae and Signiphoridae) of Hypogeococcus spp. Mealybugs (Hemiptera: Pseudococcidae) in the New World

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    Se informan los resultados de los relevamientos de los parasitoides primarios y secundarios (hiperparasitoides) de Hypogeococcus spp. (Hemiptera: Pseudococcidae) realizados en el Nuevo Mundo durante el perĂ­odo 2009 para 2017 para obtener enemigos naturales de la cochinilla harinosa de los cactus (Harrisia cactus mealybug) Hypogeococcus sp., que estĂĄ devastando cactus nativos en Puerto Rico y amenaza a los cactus presentes en Islas del Caribe adyacentes. Se registraron cinco especies de Encyrtidae (Hymenoptera: Chalcidoidea) como parasitoides primarios de Hypogeococcus spp., incluyendo el recientemente descrito Leptomastidea hypogeococci Triapitsyn sp. n., que es la Ășnica especie del gĂ©nero Leptomastidea GarcĂ­a Mercet en el Nuevo Mundo cuya clava de la antena de la hembra es contrastantemente blanca. El anĂĄlisis genĂ©tico de los individuos de L. hypogeococci de Argentina, Brasil y Puerto Rico (EE. UU.) corrobora los datos morfolĂłgicos de que la misma especie se encuentra en AmĂ©rica del Sur, las islas del Caribe y Florida (EE. UU.). Se proporciona una clave para las especies del Nuevo Mundo de Leptomastidea. Leptomastidea antillicola Dozier, syn. n. de Puerto Rico es sinonimizado bajo L. abnormis (Girault). Basado en los datos moleculares presentados, Anagyrus ciomperliki Triapitsyn syn. n. (Encyrtidae), originalmente descrito de Puerto Rico, es sinonimizado bajo A. quilmes Triapitsyn, Logarzo & Aguirre, cuyo rango de distribuciĂłn conocido tambiĂ©n se amplĂ­a para incluir a Brasil. Anagyrus cachamai Triapitsyn, Logarzo y Aguirre, A. lapachosus Triapitsyn, Aguirre y Logarzo y A. quilmes se registraron recientemente en Paraguay. Se describe el macho previamente desconocido de Prochiloneurus argentinensis (De Santis) (Encyrtidae) de la provincia de Misiones de Argentina, y el de P. narendrani Noyes & Triapitsyn de la Isla de Mona, Puerto Rico. Hasta aquĂ­, Anagyrus cachamai y A. lapachosus se consideran como las principales especies para la introducciĂłn desde Argentina y Paraguay a Puerto Rico para el control biolĂłgico de la cochinilla harinosa de los cactus. El holotipo de Anagyrus tanystis De Santis de Buenos Aires, Argentina, cuyos hospederos asociados son desconocidos, se ilustra para facilitar su reconocimiento de otras especies congenĂ©ricas.Parasitoids, both primary and secondary (hyperparasitoids), of Hypogeococcus spp. mealybugs (Hemiptera: Pseudococcidae) are reviewed to report results of the surveys in the New World conducted during 2009 to 2017 for prospective natural enemies of the Harrisia cactus mealybug, Hypogeococcus sp., which is devastating native cacti in Puerto Rico and threatening cacti in the adjacent Caribbean islands. Five species of Encyrtidae (Hymenoptera: Chalcidoidea) are recorded as primary parasitoids of Hypogeococcus spp., including the newly described Leptomastidea hypogeococci Triapitsyn sp. n., which is the only species of the genus Leptomastidea GarcĂ­a Mercet in the New World where the clava of the female antenna is contrastingly white. Genetic analysis of the individuals of L. hypogeococci from Argentina, Brazil, and Puerto Rico (USA) corroborates the morphological data that the same species occurs in South America, the Caribbean islands, and Florida (USA). A key to the New World species of Leptomastidea is given and taxonomic notes are provided on its other known species in the Neotropical region. Leptomastidea antillicola Dozier, syn. n. from Puerto Rico is synonymized under L. abnormis (Girault). Based on the presented molecular data, Anagyrus ciomperliki Triapitsyn syn. n. (Encyrtidae), originally described from Puerto Rico, is synonymized under A. quilmes Triapitsyn, Logarzo & Aguirre, where the known distributional range is expanded to also include Brazil. Anagyrus cachamai Triapitsyn, Logarzo & Aguirre, A. lapachosus Triapitsyn, Aguirre & Logarzo, and A. quilmes are newly recorded from Paraguay. The previously unknown male of Prochiloneurus argentinensis (De Santis) (Encyrtidae) is described from Misiones Province of Argentina, and that of P. narendrani Noyes & Triapitsyn is described from Mona Island, Puerto Rico. So far, Anagyrus cachamai and A. lapachosus are considered to be the primary target species for introduction from Argentina and Paraguay into Puerto Rico for the biological control of Harrisia cactus mealybug. The holotype of Anagyrus tanystis De Santis from Buenos Aires, Argentina, host associations are unknown, and is illustrated to facilitate its recognition from other congeneric species.Fil: Triapitsyn, Serguei V.. University of California; Estados UnidosFil: Aguirre, MarĂ­a BelĂ©n. FundaciĂłn para el Estudio de Especies Invasivas; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Logarzo, Guillermo Alejandro. FundaciĂłn para el Estudio de Especies Invasivas; ArgentinaFil: Hight, Stephen D.. United States Department of Agriculture. Agriculture Research Service; Estados UnidosFil: Ciomperlik, Matthew A.. United States Department of Agriculture. Agriculture Research Service; Estados UnidosFil: Rugman Jones, Paul F.. University of California; Estados UnidosFil: Rodrigues, Jose C. Verle. Universidad de Puerto Rico; Puerto Ric

    Foundation and empire : a critique of Hardt and Negri

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    In this article, Thompson complements recent critiques of Hardt and Negri's Empire (see Finn Bowring in Capital and Class, no. 83) using the tools of labour process theory to critique the political economy of Empire, and to note its unfortunate similarities to conventional theories of the knowledge economy

    A perspective on multinational enterprise’s national identity dilemma

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    This conceptual paper identifies gaps and contributes to the literature on ‘identity’ dilemmas faced by multinational enterprises operating in a globalised world. Various characteristics and business strategies of multinational enterprises are delineated and analysed through the lens of social identity theory and international business concepts such as market and institutional logic. Our analysis, based on multiple cases, and derived from a variety of industries and countries, associates the identity dilemma to informed business strategy. Our findings suggest that while multinational enterprises face identity dilemmas that they sometimes use to their advantage, it also poses several challenges. Through our conceptualisation, we derive five distinct propositions to shape future research directions

    Business group affiliation and foreign subsidiary performance

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    Research Summary Business group (BG) affiliation affects the strategic behavior and performance of firms. Until now it has been theoretically unclear and insufficiently empirically tested whether affiliation advantages extend to the foreign subsidiaries of group members. We attempt to determine if they do, and if so, to identify the boundary conditions that matter. We analyze a large panel of 451 foreign subsidiaries of 136 Indian multinational firms over the 2003-2012 period and find that BG affiliation does enhance foreign subsidiary performance when host-market institutions are weak and when the parent is in manufacturing. Managerial Summary Our research speaks directly to managers of multinational firms who seek to leverage the benefits of BG affiliation across national borders. We show that BG affiliation is only beneficial when the foreign subsidiary is located in a country characterized by weak institutions and when the parent is in manufacturing. If, on the other hand, the foreign subsidiary is in a country with well-functioning institutions and the parent in services, managers will not be able to count on BG advantages, rather they will have to develop competitive capabilities locally, that is, the foreign subsidiary will have to function more like a standalone firm

    Internationalisation speed and MNE performance: A study of the market-seeking expansion of retail MNEs

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    Existing research is divided on whether firms that rapidly expand their overseas operations perform better than firms that internationalize slowly. Drawing on Penrose’s theory of the growth of the firm we argue that the positive effects of rapid internationalization give way to negative effects with increasing internationalization speed, leading to an inverted U-shaped association between internationalization speed and firm performance. We analyse the market-seeking expansion of 110 retailers over a 10-year period (2003–2012) and find support for a curvilinear relationship between internationalization speed and firm performance that is moderated by the geographic scope of firms’ internationalization path and firms’ international experience. Our study contributes to resolving conflicting views on the link between internationalization speed and firm performance

    How do MNC R&D laboratory roles affect employee international assignments?

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    Research and development (R&D) employees are important human resources for multinational corporations (MNCs) as they are the driving force behind the advancement of innovative ideas and products. International assignments of these employees can be a unique way to upgrade their expertise; allowing them to effectively recombine their unique human resources to progress existing knowledge and advance new ones. This study aims to investigate the effect of the roles of R&D laboratories in which these employees work on the international assignments they undertake. We categorise R&D laboratory roles into those of the support laboratory, the locally integrated laboratory and the internationally interdependent laboratory. Based on the theory of resource recombinations, we hypothesise that R&D employees in support laboratories are not likely to assume international assignments, whereas those in locally integrated and internationally interdependent laboratories are likely to assume international assignments. The empirical evidence, which draws from research conducted on 559 professionals in 66 MNC subsidiaries based in Greece, provides support to our hypotheses. The resource recombinations theory that extends the resource based view can effectively illuminate the international assignment field. Also, research may provide more emphasis on the close work context of R&D scientists rather than analyse their demographic characteristics, the latter being the focus of scholarly practice hitherto
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