323 research outputs found
Ruthenium polypyridyl complexes and their modes of interaction with DNA : is there a correlation between these interactions and the antitumor activity of the compounds?
Various interaction modes between a group of six ruthenium polypyridyl complexes and DNA have been studied using a number of spectroscopic techniques. Five mononuclear species were selected with formula [Ru(tpy) L1L2](2-n)?, and one closely related dinuclear cation of formula [{Ru(apy)(tpy)}2{l-H2N(CH2)6NH2}]4?. The ligand tpy is 2,20:60,200-terpyridine and the ligand L1 is a bidentate ligand, namely, apy (2,20-azobispyridine), 2-phenylazopyridine, or 2-phenylpyridinylmethylene amine. The ligand L2 is a labile monodentate ligand, being Cl-, H2O, or CH3CN. All six species containing a labile L2 were found to be able to coordinate to the DNA model base 9-ethylguanine by 1H NMR and mass spectrometry. The dinuclear cationic species, which has no positions available for coordination to a DNA base, was studied for comparison purposes. The interactions between a selection of four representative complexes and calf-thymus DNA were studied by circular and linear dichroism. To explore a possible relation between DNA-binding ability and toxicity, all compounds were screened for anticancer activity in a variety of cancer cell lines, showing in some cases an activity which is comparable to that of cisplatin. Comparison of the details of the compound structures, their DNA binding, and their toxicity allows the exploration of structure–activity relationships that might be used to guide optimization of the activity of agents of this class of compounds
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The effects of market economy and foreign MNE subsidiaries on the convergence and divergence of HRM
This study explores patterns of human resource management (HRM) practices across market economies, and between indigenous firms and foreign MNE subsidiary operations, offering a novel perspective on convergence and divergence. Applying institutional theorizing to improve our understanding of convergence/ divergence as a process and an outcome, data collected from nine countries at three points in time over a decade confirm that convergence and divergence occur to different extents in a non-linear fashion, and vary depending on the area of HRM practice observed. Patterns of adoption and convergence/ divergence are explained through the effect of institutional constraints, which vary between liberal and coordinated market economies, and between indigenous firms and foreign MNE subsidiaries. The study contributes a more graded conceptualization of convergence/ divergence, which reflects the complex dynamic reality of international business
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Decision-making in international business
This paper distinguishes three domains of international business theory: the boundaries of the multinational enterprise, the external environment of the enterprise and its internal structure. The central concern of internalisation theory is the boundaries of the firm. Any general theory of international business must analyse the external environment and internal structure as well. Competition dominates the external environment whilst co-operation dominates internal structure. Different models of decision-making are required for each. Different theories of decision-making must therefore be integrated in order to transform internalisation theory into a general theory of international business. This paper examines how this can be done
Selenium enrichment of broccoli sprout extract increases chemosensitivity and apoptosis of LNCaP prostate cancer cells
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Knowledge Transfer and Accomodation Effects in Multinational Corporations: Evidence from European Subsidiaries
Foreign subsidiaries in multinational corporations (MNCs) possess knowledge that has different sources (e.g., the firm itself or various sources in the environment). How such sources influence knowledge transfer is not well understood. Drawing on the “accommodation effect” from cognitive psychology, the authors argue that accumulation of externally sourced knowledge in a subsidiary may reduce the value of transferring that subsidiary’s knowledge to other parts of the MNC. The authors develop a parsimonious model of intrafirm knowledge transfer and test its predictions against a unique data set on subsidiary knowledge development that includes the sources of subsidiary knowledge and the extent of knowledge transfer to other MNC units. The authors show that a high level of externally sourced knowledge in a subsidiary is associated with a high level of knowledge transfer from that subsidiary only if a certain tipping point of internally sourced knowledge has been surpassed. This suggests that subsidiary knowledge stocks that are balanced in terms of their origins tend to be more valuable, congruous, and fungible, and therefore more likely to be transferred to other MNC units
Subsidiary Business Networks and Opportunity Development in Multinational Enterprises: A Comparison of the Influence of Internal and External Business Networks
Cultural Distance and Firm Internationalization:A Meta-Analytical Review and Theoretical Implications
This paper presents the most comprehensive review and meta-analysis of the literature on cultural distance and firm internationalization to date. We analyze the effects of cultural distance on key strategic decisions throughout the entire process of internationalization. For the preinvestment stage, we examine the decisions on where to invest (location choice), how much to invest (degree of ownership), and how to organize the foreign expansion (entry and establishment mode). For the postinvestment stage, we examine the decisions of how to integrate the foreign subsidiary into the organization (transfer of practices) as well as the performance effects of cultural distance at both the subsidiary and the firm level. We find that firms are less likely to expand to culturally distant locations but if they do, they prefer greenfield investments and integrate subsidiaries more through transfer of management practices. Cultural distance does not seem to affect how much capital firms invest and whether they enter through a joint venture or full ownership. Interestingly, cultural distance has a strong negative effect on subsidiary performance but no effect on the performance of the whole multinational company. In addition, we find that the effects of cultural distance are not sensitive to time, but they are sensitive to the cultural framework used (e.g., Hofstede vs. Global Leadership and Organizational Behavior Effectiveness) and the home country of the company (developed vs. emerging market). Based on our study, we feel confident to offer some theoretical insights, recommendations for improving the validity and reliability of cultural-distance research, and ideas for future research
Children, care, career – a cross-sectional study on the risk of burnout among German hospital physicians at different career stages
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