Internationalization tactics and enterprise value in the context of the "Belt and Road" initiative-Analysis from the perspective of host country institutional environment and enterprise digital transformation.

This paper analyzes the impact of internationalization tactics on the value of 1107 multinational enterprises investing in the "Belt and Road" countries (regions) based on the two dimensions: entry mode and the degree of internationalization (including the breadth and depth of internationalization). It is found that the choice of sole proprietorship in the "Belt and Road" countries has a positive effect on enterprise value than joint venture. The increase of internationalization breadth and depth can promote enterprise value. Further research shows that the institutional environment of the host country and the digital transformation of enterprises significantly affect the choice of internationalization tactics and enterprise value. Specifically, the better the institutional environment of the host country and the more adequate the digital transformation of enterprises, the more inclined enterprises are to choose the sole proprietorship in the "Belt and Road" countries (regions) to obtain higher enterprise value. A good institutional environment of the host country and the digital transformation of enterprises can positively regulate the relationship between the degree of internationalization and enterprise value. these findings have important for Chinese enterprises to implement internationalization tactics rationally and scientifically, and to continuously improve enterprise value.

Determination of anabolic androgenic steroids in dietary supplements and external drugs by magnetic solid-phase extraction combined with high-performance liquid chromatography-tandem mass spectrometry.

The widespread abuse of anabolic androgenic steroids by healthy people leads to the risk of major mood disorders and heart failure; thus, the determination of anabolic androgenic steroids is vital. In this study, 17 anabolic androgenic steroids in dietary supplements and external drugs were identified, and their concentration was determined. For this purpose, polyaniline-coated magnetic nanoparticles were prepared and then subjected to magnetic solid-phase extraction combined with high-performance liquid chromatography-tandem mass spectrometry. The experimental parameters of magnetic solid-phase extraction were studied in detail, and the optimal conditions were established. Under the optimal conditions, the limits of detection were in the range of 0.001-0.02 µg/L, with relative standard deviations of 5.52-11.6% (n = 7) for all the steroids, and the enrichment factors were in the range of 20.0-24.8. The developed method was then successfully applied for the determination of 17 anabolic androgenic steroids in real samples, and dehydroepiandrosterone (prasterone) was detected in a commercially available external drug.