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Home Market Competitive Pressure and the Tendency to Internationalise:An Inverse U-shape
No full textFirm internationalisation has been a central topic of scholarly interest in international business for decades. However, the role of competitive pressure in firms’ home markets for firm internationalisation has not been investigated for the full variety of market types, despite the central role of competition in firm strategy. In this study, we examine the relationship between home market competitive pressure, operationalised by the concept of market concentration, and firm internationalisation, and propose an inverted U-shape. We find evidence for our hypothesis based on longitudinal data from more than 27,000 firm-year observations between 2007 and 2019. Our results suggest that internationalisation increases with increasing market concentration up to a certain peak, after which internationalisation declines. Moreover, managerial ability and market fluidity intensity are two important contingencies that intensify this relationship and steepen the inverted U-shape. In revealing this non-linear relationship between home market competitive pressure and firm internationalisation, we contribute to the literature on firm strategy and international business.Die Internationalisierung von Unternehmen ist ein zentraler Forschungsgegenstand im Bereich des internationalen Managements. Trotz der zentralen Rolle von Wettbewerb für die Unternehmensstrategie wurde die Rolle des Wettbewerbsdrucks in den Heimatmärkten von Unternehmen noch nicht für die gesamte Bandbreite verschiedener Marktformen untersucht.
In dieser Studie untersuchen wir den Zusammenhang zwischen dem Wettbewerbsdruck auf dem Heimatmarkt, operationalisiert durch das Konzept der Marktkonzentration, und nehmen eine Beziehung in Form eines umgekehrten U an. Unsere empirischen Untersuchungen auf Basis eines Paneldatensatzes mit mehr als 27.000 Firmenobservationen über einen Zeitraum von 2007 bis 2019 stützen unsere theoretischen Überlegungen. Die Ergebnisse deuten darauf hin, dass Internationalisierung mit zunehmender Marktkonzentration bis zu einem Maximum zunimmt und anschließend sinkt. Zusätzlich untersuchen wir den Einfluss von Managementkompetenz und Marktfluidität als moderierende Faktoren dieses Zusammenhangs. Indem wir den nicht-linearen Zusammenhang zwischen Marktkonzentration und Internationalisierung aufzeigen, leisten wir einen Beitrag in der akademischen Debatte zur (internationalen) Managementforschung
"Ich liebe Ulrike":Die R.A.F. und die Niederlande 1970 - 1980
No full textHerbst 1977: Als deutsche Mitglieder der "Rote Armee Fraktion" nach wilden Schusswechseln in Utrecht und Amsterdam in niederländischen Gefängnissen landen, eilt ihnen ein Netzwerk von niederländischen R.A.F.-Sympathisanten zu Hilfe. Jacco Pekelder fragt, wer sie waren und warum sie sich gerade für die R.A.F. einsetzten. Einige von ihnen haben sogar die deutsche R.A.F.-Debatte maßgeblich geprägt. Der Vergleich zwischen der niederländischen Haltung zur R.A.F. und der bundesdeutschen Anti-Terror-Politik führt zu überraschenden Erkenntnissen
Selbstorganisation bei neuronaler Entwicklung
No full textUnderstanding neuronal development and specialization remains a major challenge in biology. Using RNA sequencing, we analyzed transcriptional dynamics during early neuronal differentiation, focusing on BAR-domain proteins that sense membrane curvature and drive self-organization. Cultured mouse hippocampal neurons served as a model system. Among identified candidates, BAIAP2 emerged as a key I-BAR protein with alternative splice forms potentially involved in symmetry breaking and neurite initiation. Functional assays revealed that individual BAIAP2 isoforms differentially affect neuronal shape, suggesting distinct, neuron-specific roles. At the molecular level, we detected BAIAP2 in monomeric and dimeric forms, and demonstrated hetero-dimerization between splice variants. Together, these findings uncover a novel layer of regulation in early neuronal morphogenesis mediated by alternative splicing of BAIAP2
Strophanthus sarmentosus Extracts and the Strophanthus Cardenolide Ouabain Inhibit Snake Venom Proteases from Echis ocellatus
No full text'Strophanthus sarmentosus' is recognised for various ethnomedicinal applications, including treatment after snakebites. However, only limited scientific evidence exists on its antivenomous capabilities. This study investigates the efficacy of methanol and ethylacetate extracts from 'S. sarmentosus' leaves and roots against 'Echis ocellatus' venom. A non-toxic range for the extracts was determined in rats, and assays were performed to test their anti-hemorrhagic and anti-hemolytic activity as well as their influence on venom-induced blood clotting. In all of these experiments, the extracts demonstrated significant positive effects equal to or better than antivenom. Moreover, the extracts strongly inhibited and even abolished the digestion of the vasoactive neuropeptide bradykinin by snake venom metalloproteinases. Strophantus plants are known for their high content of cardiac glycosides, one of which is the commercially available ouabain, that by itself also considerably inhibited venom-induced bradykinin cleavage. Although ouabain is only present in low amounts in 'S. sarmentosus' when compared to other cardenolides of similar structure, it can be hypothesized that members of this substance class may also have inhibitory properties against venom proteases. 'S. sarmentosus' additionally contains bioactive substances such as flavonoids, terpenoids, tannins, saponins, and alkaloids, which contribute to its protective effects. The study provides scientific data to explain the success of the traditional use of 'S. sarmentosus' plant extracts as a first aid against envenomation in rural Africa
The short-chain fatty acid butyrate exerts a specific effect on VE-cadherin phosphorylation and alters the integrity of aortic endothelial cells
No full textShort-chain fatty acids (SCFAs) like butyrate (BUT) largely influence vascular integrity and are closely associated with the onset and progression of cardiovascular diseases. However, their impact on vascular endothelial cadherin (VEC), a major vascular adhesion and signaling molecule, is largely unknown. Here, we explored the effect of the SCFA BUT on the phosphorylation of specific tyrosine residues of VEC (Y731, Y685, and Y658), which are reported to be critical for VEC regulation and vascular integrity. Moreover, we shed light on the signaling pathway engaged by BUT to affect the phosphorylation of VEC. Thereby, we used phospho-specific antibodies to evaluate the phosphorylation of VEC in response to the SCFA sodium butyrate in human aortic endothelial cells (HAOECs) and performed dextran assays to analyze the permeability of the EC monolayer. The role of c-Src and SCFA receptors FFAR2 and FFAR3 in the induction of VEC phosphorylation was analyzed using inhibitors and antagonists for c-Src family kinases and FFAR2/3, respectively, as well as by RNAi-mediated knockdown. Localization of VEC in response to BUT was assessed by fluorescence microscopy. BUT treatment of HAOEC resulted in the specific phosphorylation of Y731 at VEC with minor effects on Y685 and Y658. Thereby, BUT engages FFAR3, FFAR2, and c-Src kinase to induce phosphorylation of VEC. VEC phosphorylation correlated with enhanced endothelial permeability and c-Src-dependent remodeling of junctional VEC. Our data suggest that BUT, an SCFA and gut microbiota-derived metabolite, impacts vascular integrity by targeting VEC phosphorylation with potential impact on the pathophysiology and therapy of vascular diseases
Unraveling haplotype errors in the DFNA33 locus
No full textGenetic heterogeneity makes it difficult to identify the causal genes for hearing loss. Studies from previous decades have mapped numerous genetic loci, providing critical supporting evidence for gene discovery studies. Despite widespread sequencing accessibility, many historically mapped loci remain without a causal gene. The DFNA33 locus was mapped in 2009 and coincidentally contains 'ATP11A', a gene recently associated with autosomal dominant hearing loss and auditory neuropathy type 2. In a rare opportunity, we genome-sequenced a member of the original family to determine whether the DFNA33 locus may also be assigned to 'ATP11A'. We identified a deep intronic variant in 'ATP11A' that showed evidence of functionally normal splicing. Furthermore, we re-assessed haplotypes from the originally published DFNA33 family and identified two double recombination events and one triple recombination event in the pedigree, a highly unlikely occurrence, especially at this scale. This brief research report also serves as a call to the community to revisit families who have previously been involved in gene mapping studies, provide closure, and resolve these historical loci
"Viele Bildungseinrichtungen werden nicht finanzierbar sein" / Reformwille erkennbar :Wie der Theologe Norbert Köster die Krise der katholischen Kirche bewertet
No full textMit Blick auf den deutlichen Mitgliederrückgang in der katholischen Kirche – von über 28 Millionen Katholiken im Jahr 1990 auf mittlerweile rund 20 Millionen – sieht der Theologe Prof. Dr. Norbert Köster von der Universität Münster vor allem finanzielle Gründe sowie Veränderungen in der individuellen Lebenswelt als zentrale Faktoren für diesen Trend. "Seit dem Missbrauchsskandal ist zudem eine dritte Gruppe hinzugekommen, die der Kirche nicht mehr traut", gibt der Wissenschaftler in der neuen Folge des "Umdenken"-Podcasts zu bedenken.
Die Folgen dieser Entwicklung seien bereits heute deutlich spürbar. Viele Pfarrheime und Kitas der Bistümer stünden auf der Kippe. "Vor allem Bildungseinrichtungen werden auf Dauer nicht mehr finanzierbar sein", prognostiziert der Experte. Auch international kämpfe die deutsche katholische Kirche mit einem schlechten Ruf. Im Vatikan gelte sie mitunter als "oberreich, arrogant und protestantisch verseucht", schildert der Wissenschaftler.
Gleichwohl erkennt Norbert Köster Reformbemühungen innerhalb der Kirche. So würden beispielsweise zunehmend Frauen in zuvor männlich dominierte Ämter berufen. "Es kommt etwas in Gang – wenn auch nur in kleinen Schritten", konstatiert Norbert Köster
Mechanisms involved in extracellular (e)DNA-dependent staphylococcal biofilm formation
No full textZiel dieser Studie war die Untersuchung der Rolle des comE-Operons bei der durch extrazelluläre (e)DNA vermittelten Biofilmbildung in Staphylococcus lugdunensis. Die Inaktivierung des gesamten comE-Operons sowie von Kombinationen aus comEA, comEB und comEC ergab, dass ausschließlich Mutationen in comEB zu einer signifikanten Abnahme der Biofilmproduktion führten. Dieser Phänotyp war mit reduzierten eDNA-Mengen in der Biofilm-Matrix assoziiert. Die heterologe Expression des comE-Operons in S. carnosus führte zu einer Zunahme von Biofilm und eDNA in der Matrix. In DNA-Protein-Interaktionsassays mit rekombinanten ComE-Proteinen zeigte nur ComEC eine ausgeprägte DNA-Bindungsaktivität. Die Herstellung von Antikörpern gegen die ComE Proteine führte zur Detektion von ComEB in der extrazellulären Fraktion von Zelllysaten. Durch die Konstruktion eines ComEB-GFP Fluorophor-Fusionsproteins wurde das Fluoreszenzsignal als auf diskrete, fokale Zellbereiche beschränkt, detektiert
Novel Therapeutic Strategies for Dyslipidemia: First Report of Inclisiran Therapy in a Kidney Transplanted Patient
No full textOn the relation between periodically deflected and transverse mode-locked laser beams
No full textTransverse mode-locked (TML) beams exhibit high-speed beam scanning, which motivates a comparison with established beam deflection technologies, such as galvanometer and voice coil scanners. This study explores the hypothesis that TML beams can be regarded as high-speed equivalents of such periodically deflected beams. By analytically modeling the spatiotemporal properties of TML beams as well as experimentally examining periodically deflected beams, both their intensity and phase dynamics were assessed. It is shown that TML beams yield a scanning motion which is shape-invariant upon propagation and have characteristic spatiotemporal phase dynamics. While TML-like scanning in intensity can be recreated by combining periodic translational and rotational deflection, beams deflected by mirrors still exhibit different phase dynamics. These findings imply that TML beams cannot simply be categorized as high-speed variants of periodically deflected beams. Nonetheless, TML beams remain applicable to high-speed laser beam scanning, although their phase dynamics have to be considered in phase-sensitive processes