The numerous γ-aminobutyric acid type A receptor (GABAAR) subtypes are differentially expressed and mediate distinct functions at neuronal level. In this study we have investigated GABAAR-mediated ...modulation of the spontaneous activity patterns of primary neuronal networks from murine frontal cortex by characterizing the effects induced by a wide selection of pharmacological tools at a plethora of activity parameters in microelectrode array (MEA) recordings. The basic characteristics of the primary cortical neurons used in the recordings were studied in some detail, and the expression levels of various GABAAR subunits were investigated by western blotting and RT-qPCR. In the MEA recordings, the pan-GABAAR agonist muscimol and the GABABR agonist baclofen were observed to mediate phenotypically distinct changes in cortical network activity. Selective augmentation of αβγ GABAAR signaling by diazepam and of δ-containing GABAAR (δ-GABAAR) signaling by DS1 produced pronounced changes in the majority of the activity parameters, both drugs mediating similar patterns of activity changes as muscimol. The apparent importance of δ-GABAAR signaling for network activity was largely corroborated by the effects induced by the functionally selective δ-GABAAR agonists THIP and Thio-THIP, whereas the δ-GABAAR selective potentiator DS2 only mediated modest effects on network activity, even when co-applied with low THIP concentrations. Interestingly, diazepam exhibited dramatically right-shifted concentration-response relationships at many of the activity parameters when co-applied with a trace concentration of DS1 compared to when applied alone. In contrast, the potencies and efficacies displayed by DS1 at the networks were not substantially altered by the concomitant presence of diazepam. In conclusion, the holistic nature of the information extractable from the MEA recordings offers interesting insights into the contributions of various GABAAR subtypes/subgroups to cortical network activity and the putative functional interplay between these receptors in these neurons.
Due to the high costs and strategic importance of expatriate assignments, expatriate performance management (EPM) plays an increasingly important role for multinational enterprises (MNEs). However, ...research on EPM is still in its infancy. Drawing from the convergence/divergence debate in international human resource management, this study investigates and compares EPM strategies and practices across MNEs from three different country clusters to better understand whether EPM practices tend to converge, diverge, or crossverge (i.e., show aspects of both). Results from surveying 132 Anglo‐Saxon, Germanic, and Japanese MNEs reveal prominent differences (divergence) at the EPM strategic level such that Japanese MNEs tend to pursue more ethnocentric staffing strategies and design EPM systems specifically tailored to expatriates. On the practice level, we found both commonalities and differences between Japanese and Anglo‐Saxon and Germanic MNEs, pointing toward crossvergence. Theoretical and practical implications of our results are discussed.
To increase the long‐term benefits of global mobility for multinational corporations, international assignments and intraorganizational careers must be strategically integrated. However, systematic ...research on former expatriates' career success upon returning to their home organization remains scarce. Hence, this study transfers findings from the career literature to the repatriation context to identify the predictors of objective and subjective repatriate career success. Integrating traditional and protean career theory, we investigate data from 295 repatriates of publicly listed German organizations. Applying partial least squares structural equation modeling, we reveal that objective career success upon repatriation is affected by international assignment characteristics with human capital implications, repatriation support provided by the organization, and the individual's self‐directed career management. Objective career success, organizational repatriation support, and self‐directed career management further affect subjective career success in terms of career satisfaction. Hence, substantiating an impact of both traditional and protean career factors on repatriate careers, our results lay the groundwork for repatriation strategies that combine organizational and individual career management. In this way, multinational corporations can go beyond managing repatriate elites to make better use of all globally experienced employees.
Abstract
Brain development is likely impacted by micronutrients. This is supported by the effects of the ω-3 fatty acid docosahexaenoic acid (DHA) during early neuronal differentiation, when it ...increases neurite growth. Aiming to delineate DHA roles in postnatal stages, we selected the visual cortex due to its stereotypic maturation. Immunohistochemistry showed that young mice that received dietary DHA from birth exhibited more abundant presynaptic and postsynaptic specializations. DHA also increased density and size of synapses in a dose-dependent manner in cultured neurons. In addition, dendritic arbors of neurons treated with DHA were more complex. In agreement with improved connectivity, DHA enhanced physiological parameters of network maturation in vitro, including bursting strength and oscillatory behavior. Aiming to analyze functional maturation of the cortex, we performed in vivo electrophysiological recordings from awake mice to measure responses to patterned visual inputs. Dietary DHA robustly promoted the developmental increase in visual acuity, without altering light sensitivity. The visual acuity of DHA-supplemented animals continued to improve even after their cortex had matured and DHA abolished the acuity plateau. Our findings show that the ω-3 fatty acid DHA promotes synaptic connectivity and cortical processing. These results provide evidence that micronutrients can support the maturation of neuronal networks.
This study analyzes the antecedents of expatriate work attitudes in terrorism-endangered countries. Applying a social exchange perspective, the study empirically analyzes which measures are qualified ...to achieve and maintain positive work attitudes among expatriates. Hierarchical regression analysis is applied to investigate this relationship, using data from 143 expatriates in high-risk countries. Data show that social support from co-workers as well as from the organization itself is essential. Moreover, the study investigates the expatriate's sensitivity to terrorism as a moderator and finds that companies should incorporate the sensitivity in their considerations for corporate measures.
Traditional corporate expatriate assignments play a crucial role in driving Multinational Corporations’ (MNCs’) business. While expatriate management literature long concentrated on facilitating the ...employees’ actual stay in the host countries, seminal research in the early 1990s demonstrated that their return home is entailed by crucial challenges as well. Scholarly interest in the topic of repatriation has increased considerably ever since. Over the past three decades, research has addressed a broad array of aspects to be considered upon the return of expatriates. Nevertheless, so far very few MNCs have formal repatriation strategies in place. However, by failing to manage the return of expatriates, firms jeopardize their corporate return on investment (cROI) of expatriation. Many of the repatriation outcomes discussed in existing research can have an effect on cROI as they create late but substantial costs and/or benefits for assigning MNCs. In order to further enhance the strategic integration of repatriation into the expatriate management process as well as to pave the way for future research on this important topic, this study reviews the current state of repatriation literature from a cROI-perspective. By examining 51 articles, we identify the range of cROI-affecting repatriation outcomes addressed so far in order to then classify the variables encountered according to their cost and benefit potential to assigning firms. We thereby outline potential shortcomings in existing literature to eventually deduce an agenda for future research on repatriation that aims at maximizing cROI in the long run.
•MEA was used to analyze spontaneous electrical activity in NPC1−/− cortical neurons.•The electrical activity in NPC1−/− neurons decreased during neuronal development.•Application of DHPG improved ...the defective electrical activity in NPC1−/− neurons.
Niemann-Pick Type C1 (NPC1) disease is an autosomal recessive neurodegenerative disease characterized by an excessive accumulation of unesterified cholesterol in late endosomes/lysosomes. Patients with NPC1 disease show a series of symptoms in neuropathology, including a gradually increased loss of motor control and seizures. However, mechanism of the neurological manifestations in NPC1 disease is not fully understood yet. In this study, we utilized the micro-electrode array (MEA) to analyze the spontaneous extracellular electrical activity in cultivated cortical neurons of the NPC1 mutant (NPC1−/−) mouse. Our results show a decrease of the spontaneous electrical activity in NPC1−/− neuronal network when compared to wild type neurons, as indicated by the decreased spike rate, burst rate, event rate, and the increased burst period and event period. Application of 3,5-dihydroxyphenylglycine (DHPG), a specific agonist of group I metabotropic glutamate receptors, improved the electrical activity of the NPC1−/− neuronal network, suggesting that DHPG can be used as a potential therapeutic strategy for recovery of the electrical activity in NPC1 disease.
Purpose
The purpose of this paper is to analyze the impact of personality and mentorship on expatriates’ psychological well-being. The authors argue that certain personality traits (extraversion, ...agreeableness, conscientiousness, emotional stability, and openness to experience) have positive effects on expatriates’ psychological well-being and that these personality traits enable them to derive a greater benefit from mentorship. By doing so, this study identifies for which personality traits which type of mentoring (home or host country mentor) is most beneficial.
Design/methodology/approach
Based on socioanalytic theory, the authors develop theory-driven hypotheses and test them against data of 334 expatriates.
Findings
The study shows that several personality traits as well as home country mentorship have a significant positive impact on psychological well-being, whereas host country mentorship shows no significant positive effects. Moreover, the study indicates that home and host country mentorship partially moderates the relationship between personality traits and psychological well-being.
Originality/value
Since the authors derive important implications for the selection process of expatriates as well as for the implementation of mentoring in multinational corporations, this study is of value for researchers and practitioners in the areas of human resource management and organizational studies.
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