In at the Deep End of Firm Internationalization

• The purpose of this research is to examine the consequences of top management team (TMT) internationalization: why and under what conditions can TMT nationality diversity be beneficial?
• On the basis of the upper echelons theory from the strategic leadership literature, the relationship between the TMT nationality diversity and firm performance in the strategic context of firm internationalization is investigated in moderated multiple regressions models (MMR) for a sample of Dutch, Swiss, and UK companies.
• The study findings suggest that the TMT nationality diversity becomes advantageous only in firms with high degree of internationalization. Companies have to be strongly committed to foreign markets so that the benefits of the TMT nationality diversity can materialize.
• The arising managerial implication is that the TMT nationality diversity can be a powerful tool in building a firm’s competitive advantage, provided that companies are strongly exposed to the international environment. The study also provides corroborative evidence that the search for moderating and mediating variables in the TMT demography research represents a step in the right direction.

     

Characterization of Aptamer-Protein Complexes by X-ray Crystallography and Alternative Approaches

Aptamers are oligonucleotide ligands, either RNA or ssDNA, selected for high-affinity binding to molecular targets, such as small organic molecules, proteins or whole microorganisms. While reports of new aptamers are numerous, characterization of their specific interaction is often restricted to the affinity of binding (K(D)). Over the years, crystal structures of aptamer-protein complexes have only scarcely become available. Here we describe some relevant technical issues about the process of crystallizing aptamer-protein complexes and highlight some biochemical details on the molecular basis of selected aptamer-protein interactions. In addition, alternative experimental and computational approaches are discussed to study aptamer-protein interactions.     

The internationalization-performance relationship at Swiss firms: A test of the S-shape and extreme degrees of internationalization

Abstract and Key Results

Conformational flexibility and polymerization of vesicular stomatitis virus matrix protein

The matrix protein of vesicular stomatitis virus (VSV) plays a pivotal role in viral assembly. We previously demonstrated the ability of M protein to self-associate at low salt concentrations. Now, we show the ability of M protein to polymerize in the presence of ZnCl2 in a nucleation-dependent manner. Analysis of kinetics revealed that the nuclei are probably made of three or four molecules of M. These results are consistent with the idea that in vitro self association of M protein is not due to amorphous aggregation but rather reflects an intrinsic ability of M to polymerize. Using attenuated total reflectance Fourier transform infrared spectroscopy, we showed that M polymerization is associated with an increase in the beta-sheet content of the protein. We propose a model explaining both the apparent M protein solubility in infected cells and how M polymerization could promote viral assembly. Data available for other negative strand viruses suggest that M polymerization may be the general basis of viral assembly.     

Reliability of velocity pulsatility in small vessels on 3Tesla MRI in the basal ganglia: a test–retest study

Objective

Recent work showed the feasibility of measuring velocity pulsatility in the perforating arteries at the level of the BG using 3T MRI. However, test–retest measurements have not been performed, yet. This study assessed the test–retest reliability of 3T MRI blood flow velocity measurements in perforating arteries in the BG.

Materials and methods

Two-dimensional phase-contrast cardiac gated (2D-PC) images were acquired for 35 healthy controls and repeated with and without repositioning. 2D-PC images were processed and analyzed, to assess the number of detected perforating arteries (N_detected), mean blood flow velocity (V_mean), and velocity pulsatility index (vPI). Paired t-tests and Bland–Altman plots were used to compare variance in outcome parameters with and without repositioning, and limits of agreement (LoA) were calculated.

Results

The LoA was smallest for V_mean (35%) and highest for vPI (79%). Test–retest reliability was similar with and without repositioning of the subject.

Discussion

We found similar LoA with and without repositioning indicating that the measurement uncertainty is dominated by scanner and physiological noise, rather than by planning. This enables to study hemodynamic parameters in perforating arteries at clinically available scanners, provided sufficiently large sample sizes are used to mitigate the contribution of scanner- and physiological noise.

     

Discrimination of heavy and light elements in a specimen by use of scanning transmission electron microscopy

Heavier elements have a larger scattering cross-section for elastically scattered electrons than lighter ones. Furthermore, the maximum number of scattered electrons is at higher scattering angles for heavier atoms. These differences can be used, in principle, to distinguish heavy and light elements from each other in dark field Scanning Transmission Electron Microscopy (STEM). We have achieved such discrimination in practice by collecting the electrons in a STEM experiment at two different angles. The information about the elemental composition that these two images together contain is visualized by forming linear combinations of the images which are specific for light and heavy elementsrrespectively. The results are demonstrated for a specimen consisting of platinum grains on a holey carbon film and for granulocytes stained with osmium tetroxide.     

Designing for safety: the ‘free flight’ air traffic management concept

This paper describes the conceptual design and validation of an air traffic management (ATM) concept and the role the safety and human factors played in this design and validation process. The free flight (FF) concept is characterised by being a direct route concept where the pilots, instead of the air traffic controller, are responsible for the separation assurance. Moving this task to the cockpit has consequences for the man machine interface in the cockpit, which needs to be modified to accommodate this new task (micro level design). On top of that, a set of rules and procedures are required to ensure an efficient and safe traffic flow (macro level design). Both the micro and macro aspect of this design are intertwined and require an accurate tuning to arrive at an overall acceptable solution. Both micro-level (flight simulator) experiments and macro-level (traffic simulations) experiments have been conducted to investigate the feasibility of this concept after optimising the initial conceptual design.