Modeling effects of L-type ca(2+) current and na(+)-ca(2+) exchanger on ca(2+) trigger flux in rabbit myocytes with realistic T-tubule geometries.

The transverse tubular system of rabbit ventricular myocytes consists of cell membrane invaginations (t-tubules) that are essential for efficient cardiac excitation-contraction coupling. In this study, we investigate how t-tubule micro-anatomy, L-type Ca(2+) channel (LCC) clustering, and allosteric activation of Na(+)/Ca(2+) exchanger by L-type Ca(2+) current affects intracellular Ca(2+) dynamics. Our model includes a realistic 3D geometry of a single t-tubule and its surrounding half-sarcomeres for rabbit ventricular myocytes. The effects of spatially distributed membrane ion-transporters (LCC, Na(+)/Ca(2+) exchanger, sarcolemmal Ca(2+) pump, and sarcolemmal Ca(2+) leak), and stationary and mobile Ca(2+) buffers (troponin C, ATP, calmodulin, and Fluo-3) are also considered. We used a coupled reaction-diffusion system to describe the spatio-temporal concentration profiles of free and buffered intracellular Ca(2+). We obtained parameters from voltage-clamp protocols of L-type Ca(2+) current and line-scan recordings of Ca(2+) concentration profiles in rabbit cells, in which the sarcoplasmic reticulum is disabled. Our model results agree with experimental measurements of global Ca(2+) transient in myocytes loaded with 50 μM Fluo-3. We found that local Ca(2+) concentrations within the cytosol and sub-sarcolemma, as well as the local trigger fluxes of Ca(2+) crossing the cell membrane, are sensitive to details of t-tubule micro-structure and membrane Ca(2+) flux distribution. The model additionally predicts that local Ca(2+) trigger fluxes are at least threefold to eightfold higher than the whole-cell Ca(2+) trigger flux. We found also that the activation of allosteric Ca(2+)-binding sites on the Na(+)/Ca(2+) exchanger could provide a mechanism for regulating global and local Ca(2+) trigger fluxes in vivo. Our studies indicate that improved structural and functional models could improve our understanding of the contributions of L-type and Na(+)/Ca(2+) exchanger fluxes to intracellular Ca(2+) dynamics

Building professional discourse in emerging markets: Language, context and the challenge of sensemaking

Using ethnographic evidence from the former Soviet republics, this article examines a relatively new and mainly unobserved in the International Business (IB) literature phenomenon of communication disengagement that manifests itself in many emerging markets. We link it to the deficiencies of the local professional business discourse rooted in language limitations reflecting lack of experience with the market economy. This hampers cognitive coherence between foreign and local business entities, adding to the liability of foreignness as certain instances of professional experience fail to find adequate linguistic expression, and complicates cross-cultural adjustments causing multi-national companies (MNCs) financial losses. We contribute to the IB literature by examining cross-border semantic sensemaking through a retrospectively constructed observational study. We argue that a relative inadequacy of the national professional idiom is likely to remain a feature of business environment in post-communist economies for some time and therefore should be factored into business strategies of MNCs. Consequently, we recommend including discursive hazards in the risk evaluation of international projects

Developing international business relationships in a Russian context

The collapse of the former Soviet Union has opened up a wealth of business opportunities for companies seeking new markets in the Russian Federation. Despite this, firms intending to do business in Russia have found themselves hampered by cultural differences in business practices and expectations. As Russia integrates into the global economy, understanding such practices and the managerial mindset of business people is crucial for managers who hope to navigate Russia's complex markets. This study draws on the trust literature and adopts quantitative tools to deconstruct the Russian 'Sviazi' system of social capital business networking. We develop a model isolating three dimensions of Sviazi: one an affective or emotional component; the second, a conative component; and the third, a cognitive component. The model provides a useful guide for helping foreign firms to succeed in Russia, while also serving as a basis for further research in the field. Keywords

Complexes of Zinc With Picolinic and Aspartic Acids Inactivate Free Varicella-Zoster Virions

Zn(II) picolinate and aspartate, Zn(pic)2 and Zn(asp)2, have been shown to inhibit key steps of the replication of HSV-1. In the present study we describe the effect of Zn(pic)2 and Zn(asp)2 on the replication of VZV and on the infectivity of free virions. The experiments are done using BHK-21 cells, a clinical isolate of VZV and Zn-complexes in concentration of 10 μM. When Zn-complexes are present during the whole period of infection, the yield of infectious virus progeny decreases up to 98%. The infectivity of VZV is completely restored after the removal of zinc. The virucidal effect is manifested at the 2nd h of contact, when 90% of the virions are inactivated. The results show that both Zn(pic)2 and Zn(asp)2 specifically inactivate free VZV virions with no effect on viral replication

STUDY OF THE ACUTE TOXICITY AND COMBINED ACTION OF THE PESTICIDES ACREX AND ACTELIC

No abstrac

The culture variable vis-à-vis anti-bribery law: a grey area in transnational corporate criminal liability

Cross-border transactions are generating corresponding globalisation of law enforcement efforts. Culture has significantly influenced the legal analysis of anti-bribery law. With the increase of transnational bribery, benefits from globalisation will be undermined unless an effective legal regime can mitigate the harm of bribery. It is perceived that corruption in China is more prevalent than in the West given its embedded place in Chinese culture. It is further alleged that Chinese multinational companies (MNCs) are taking advantage of an unlevel playing field, as they are not subject to stringently-enforced anti-bribery laws. This hypothesis creates a myriad of anti-bribery problems in terms of legislation and enforcement, which particularly manifest in China’s perceived cultural toleration of bribery. Cultural assumptions undermine the global anti-bribery regime and compromise potential collaborative anti-bribery efforts across jurisdictions in a rapidly globalizing world. The Chinese culture does not necessarily impede China’s criminalisation of paying bribes to foreign officials. It is argued that the cultural role should not be overestimated, otherwise the hazard of the ethnocentric engagement with the Chinese culture would affect the ability of foreign MNCs to integrate their global compliance programmes. Multinationals can only mitigate their exposure to criminal liability globally, provided that they comply robustly with anti-bribery laws of both home and host jurisdictions

Structural and functional alterations in salivary gland chromosomes and enzyme activity of Chironomus riparius Mg. (Diptera, Chironomidae) from anthropogenically polluted sites in Bulgaria and Turkey

The effect of environment contaminants on genome instability and changes in enzyme activity (acetylcholinesterase (AChE), glutathione S-transferase activities (GST), etoxyresorufin O-deethylase (EROD) and metallothionein (MT)) of Chironomus riparius Mg. from Bulgarian and Turkish stations over two years (2009, 2010) as well as laboratory reared larvae were studied. Physicochemical analysis of the sediments from the field stations indicated the presence of heavy metal pollutants (Cr, Cu, Mn, Pb, and Cd) whose concentrations were higher than the reference data. Genome instability was determined by somatic structural and functional alterations of the polytene chromosomes. In the field sites of both countries somatic aberrations occurred at a significantly higher frequency (p < 0.001) compared with control and laboratory material. C. riparius in sediments with higher concentrations of trace metals (Derincay River, Turkey and Chaya River, Bulgaria), was found to possess a high spectrum of somatic chromosome rearrangements with a somatic index of 2.53 and 3.25 respectively. Changes in functional activity included decreased activity of the Balbiani rings (BRs) and nucleolar organizer (NOR). The observed chromosome alterations agree with the high degree of trace metal pollution and high activity of the studied enzymes. However, no correlation between single somatic chromosome rearrangements and concentrations of specific metal ions was defined. The data are discussed in the light of the wide variety of interactions of metals in nature. The results show that the genome response and biochemical markers are sensitive markers of toxicity and provide early warning indicators of contaminants in the environment. © 2012 Dipartimento di Biologia Evoluzionistica

Why and how does shared language affect subsidiary knowledge inflows? A social identity perspective

We draw on social identity theory to conceptualize a moderated mediation model that examines the relationship between shared language among subsidiary and HQ managers, and subsidiaries’ knowledge inflows from HQ. Specifically, we study (1) whether this relationship is mediated by the extent to which subsidiary managers share HQ goals and vision, and the extent to which HR decisions are centralized; and (2) whether subsidiary type moderates these mediated relationships. Building on a sample of 817 subsidiaries in nine countries/regions, we find support for our model. Implications for research on HQ-subsidiary knowledge flows, social identity theory and international HRM are discussed

The German Miracle Keeps Running: How Germany's Hidden Champions Stay Ahead in the Global Economy

Despite mediocre macro-economic performance of the German economy, German companies are successful players in global trade. This article explores the strategies of one of the pillars of this export success, the Hidden Champions, Our empirical analysis focuses on leading medium size companies identified by Hermann Simon in the early 1990s, and investigates their long-term progress over one decade. We show that these companies continue to prosper with family ownership combined with professional external management, strategies of market leadership in global niches and a persistent focus on operational effectiveness. Scholars and business leaders, in particular of companies based in other high-cost countries, therefore ought to consider German companies as source for lessons on how to succeed in the global economy