On the Magnet Effect of Foreign Direct Investment

We extend Antràs and Helpman (2004) on firm heterogeneity and organizational choice to a dynamic setting with FDI uncertainty, in which the probability of investment failure decreases with the host country’s infrastructure level and increases with the technological complexity facing each firm. Moreover, it decreases over time as the accumulated mass of firms succeeding in FDI increases. We show that a minimum level of infrastructure is required to trigger a first wave of industrial migration. We then formalize the often noted “magnet effect ” of FDI–the first wave of industrial migration generates positive externality (information spillover) for subsequent investors, which stimulates a second wave of industrial migration. The process continues until the power of the “magnet ” reaches its steady-state level. In contrast with the predictions in Antràs and Helpman (2004), we show that firms with intermediate productivity levels are the ones migrate first, while the most productive and the least productive firms tend to stay behind. This non-monotonic relationship between firms ’ productivity and their FDI propensitie

Risk, Learning, and the Technology Content of FDI: A Dynamic Model

This paper builds a dynamic model to examine the two-way interaction between FDI and the South’s technology frontier. Inferior technology capacity in the South generates risk of production failure, which discourages inward FDI with high technology content. Only if the risk is not prohibitive does the first wave of FDI take place, which enables the South to learn from producing for multinationals and push forward its technology frontier. Consequently, the risk constraints are relaxed, which induces subsequent FDI with ever higher technology content. This reinforcing process implies an FD

Risk and the Technology Content of FDI: A Dynamic Model

Published in Journal of International Economics 2012, https://doi.org/10.1016/j.jinteco.2011.09.001</p

Conserved charged amino acid residues in the extracellular region of sodium/iodide symporter are critical for iodide transport activity

<p>Abstract</p> <p>Background</p> <p>Sodium/iodide symporter (NIS) mediates the active transport and accumulation of iodide from the blood into the thyroid gland. His-226 located in the extracellular region of NIS has been demonstrated to be critical for iodide transport in our previous study. The conserved charged amino acid residues in the extracellular region of NIS were therefore characterized in this study.</p> <p>Methods</p> <p>Fourteen charged residues (Arg-9, Glu-79, Arg-82, Lys-86, Asp-163, His-226, Arg-228, Asp-233, Asp-237, Arg-239, Arg-241, Asp-311, Asp-322, and Asp-331) were replaced by alanine. Iodide uptake abilities of mutants were evaluated by steady-state and kinetic analysis. The three-dimensional comparative protein structure of NIS was further modeled using sodium/glucose transporter as the reference protein.</p> <p>Results</p> <p>All the NIS mutants were expressed normally in the cells and targeted correctly to the plasma membrane. However, these mutants, except R9A, displayed severe defects on the iodide uptake. Further kinetic analysis revealed that mutations at conserved positively charged amino acid residues in the extracellular region of NIS led to decrease NIS-mediated iodide uptake activity by reducing the maximal rate of iodide transport, while mutations at conserved negatively charged residues led to decrease iodide transport by increasing dissociation between NIS mutants and iodide.</p> <p>Conclusions</p> <p>This is the first report characterizing thoroughly the functional significance of conserved charged amino acid residues in the extracellular region of NIS. Our data suggested that conserved charged amino acid residues, except Arg-9, in the extracellular region of NIS were critical for iodide transport.</p

Risk, Firm Heterogeneity, and Dynamics of FDI Entry

We study the dynamics of FDI entry under a setting with firm heterogeneity and FDI uncertainty. The risk of FDI failure depends positively on the complexity of production technology, negatively on the quality of infrastructure in the host country, and evolves over time with the extent of knowledge diffusion. The incorporation of FDI uncertainty leads to a non-monotonic relationship between technology complexity and the timing of FDI entry: firms with intermediate technology levels lead the first wave of FDI, which helps lower the investment uncertainty facing subsequent investors and induces a wider range of FDI entry in the second period. We prove the existence of a stable steady state for this self-reinforcing process and identify how the extensive margin of FDI at the steady state varies with the host and home country characteristics. Supporting empirical observations are also provided

Play as You Like: Timbre-enhanced Multi-modal Music Style Transfer

Style transfer of polyphonic music recordings is a challenging task when considering the modeling of diverse, imaginative, and reasonable music pieces in the style different from their original one. To achieve this, learning stable multi-modal representations for both domain-variant (i.e., style) and domain-invariant (i.e., content) information of music in an unsupervised manner is critical. In this paper, we propose an unsupervised music style transfer method without the need for parallel data. Besides, to characterize the multi-modal distribution of music pieces, we employ the Multi-modal Unsupervised Image-to-Image Translation (MUNIT) framework in the proposed system. This allows one to generate diverse outputs from the learned latent distributions representing contents and styles. Moreover, to better capture the granularity of sound, such as the perceptual dimensions of timbre and the nuance in instrument-specific performance, cognitively plausible features including mel-frequency cepstral coefficients (MFCC), spectral difference, and spectral envelope, are combined with the widely-used mel-spectrogram into a timber-enhanced multi-channel input representation. The Relativistic average Generative Adversarial Networks (RaGAN) is also utilized to achieve fast convergence and high stability. We conduct experiments on bilateral style transfer tasks among three different genres, namely piano solo, guitar solo, and string quartet. Results demonstrate the advantages of the proposed method in music style transfer with improved sound quality and in allowing users to manipulate the output