Fixed export costs and multi-product firms

This paper has two aims. First, we uncover some salient components of fixed export costs, which play a crucial role in recent heterogeneous firms models of international trade. Second, we investigate whether the importance of these fixed export costs varies with the size of a firms export product portfolio. We find that a destination country's institutional quality, such as the quality of regulation or the extent of corruption, form important impediments to a firm's export decision, lowering the export probability by up to 10%-points. Moreover, relative to single-product firms, multi-product firms experience additional export probability decreases of around 2%-points

Polarization stabilization in vertical-cavity surface-emitting lasers through asymmetric current injection

We present experimental evidence that asymmetric current injection in intracavity contacted vertical-cavity surface-emitting lasers (VCSELs) stabilizes the polarization of the emitted light. Anisotropies in the gain and loss mechanisms introduced by asymmetric current injection are considered to explain this effect. The design scheme opens perspectives to obtain actual polarization control in VCSEL

Study protocol for locoregional precision treatment of hepatocellular carcinoma with transarterial chemoembolisation (TACTida), a clinical study:idarubicin dose selection, tissue response and survival

INTRODUCTION: Hepatocellular carcinoma (HCC) is a common cause of cancer-related death, often detected in the intermediate stage. The standard of care for intermediate-stage HCC is transarterial chemoembolisation (TACE), where idarubicin (IDA) is a promising drug. Despite the fact that TACE has been used for several decades, treatment success is unpredictable. This clinical trial has been designed believing that further improvement might be achieved by increasing the understanding of interactions between local pharmacology, tumour targeting, HCC pathophysiology, metabolomics and molecular mechanisms of drug resistance. METHODS AND ANALYSIS: The study population of this single-centre clinical trial consists of adults with intermediate-stage HCC. Each tumour site will receive TACE with two different IDA doses, 10 and 15 mg, on separate occasions. Before and after each patient's first TACE blood samples, tissue and liquid biopsies, and positron emission tomography (PET)/MRI will be performed. Blood samples will be used for pharmacokinetics (PK) and liver function evaluation. Tissue biopsies will be used for histopathology analyses, and culturing of primary organoids of tumour and non-tumour tissue to measure cell viability, drug response, multiomics and gene expression. Multiomics analyses will also be performed on liquid biopsies. PET/MRI will be used to evaluate tumour viability and liver metabolism. The two doses of IDA will be compared regarding PK, antitumour effects and safety. Imaging, molecular biology and multiomics data will be used to identify HCC phenotypes and their relation to drug uptake and metabolism, treatment response and survival. ETHICS AND DISSEMINATION: Participants give informed consent. Personal data are deidentified. A patient will be withdrawn from the study if considered medically necessary, or if it is the wish of the patient. The study has been approved by the Swedish Ethical Review Authority (Dnr. 2021-01928) and by the Medical Product Agency, Uppsala, Sweden. TRIAL REGISTRATION NUMBER: EudraCT number: 2021-001257-31

Exploring the margins of Dutch exports: a firm-level analysis

This paper utilizes new Dutch transaction-level data on international trade to investigate the microeconomic patterns of Dutch exports. First, we show that self-selection based on ex-ante productivity drives firms’ export decisions, which we subsequently relate to various sources of fixed market-entry costs: governance and regulatory quality, the extent of corruption, and cultural proximity. Second, we provide evidence that firms learn to export by trial and error, so as to obtain experience in exporting and to gather knowledge about the potential of foreign markets. Such experimentation appears to be reflected in the volatility of a firm’s export product portfolio. More volatility is associated with a higher survival rate in the export market. Finally, we draw conclusions on the potential implications for trade policy