A Macroeconomic Approach to a Firm\u27s Capital Structure

In this paper, I investigate the logic behind cross sectional dispersion of firm\u27s capital structure. I incorporate the trade off between tax benefits and financial distress costs into a dynamic general equilibrium model with heterogeneous firms and their endogenous entry/exit, and compute an equilibrium firm distribution. The main findings are summarized as follows. First, I find that the equilibrium distribution approximates the dispersion of firms\u27 capital structure well. Second, I find that it simultaneously accounts for the relationship of capital structure to profitability \textit{and} firm size. The key mechanisms are the difference in responses to persistent and transitory productivity shocks and economies of scale. Third, I find through counterfactual experiments that even if the tax benefits do not exist, firms would not significantly change their capital structure in contrast to previous works. The intuition is that, with firm\u27s entry/exit, young firms always exist and use debt until they accumulate internal funding

A Macroeconomic Approach to Corporate Capital Structure

In this paper, I investigate the cross-sectional determinants of corporate capital structure using a general equilibrium model with endogenous firm dynamics, a realistic tax environment, and financial frictions. I find that the equilibrium firm distribution in the model replicates fairly well the distribution of corporate capital structure as well as the relationship between capital structure, profitability, and firm size in the data. The key mechanisms here are economies of scale and two types of productivity shocks: persistent and transitory. The counterfactual experiment using the model implies, among other things, that tax benefits have relatively small effects on corporate capital structure choice compared with default costs and the costs of outside equity, including the dividend tax. It also reveals that the effects of those frictions on corporate capital structure choice are highly interrelated with each other.Corporate Capital Structure, Dynamic Trade-off Theory, Heterogeneous Firm Model

Frequent Loss of Genome Gap Region in 4p16.3 Subtelomere in Early-Onset Type 2 Diabetes Mellitus

A small portion of Type 2 diabetes mellitus (T2DM) is familial, but the majority occurs as sporadic disease. Although causative genes are found in some rare forms, the genetic basis for sporadic T2DM is largely unknown. We searched for a copy number abnormality in 100 early-onset Japanese T2DM patients (onset age <35 years) by whole-genome screening with a copy number variation BeadChip. Within the 1.3-Mb subtelomeric region on chromosome 4p16.3, we found copy number losses in early-onset T2DM (13 of 100 T2DM versus one of 100 controls). This region surrounds a genome gap, which is rich in multiple low copy repeats. Subsequent region-targeted high-density custom-made oligonucleotide microarray experiments verified the copy number losses and delineated structural changes in the 1.3-Mb region. The results suggested that copy number losses of the genes in the deleted region around the genome gap in 4p16.3 may play significant roles in the etiology of T2DM

HbA1c and telemedicine during COVID-19

Aims/Introduction: To investigate whether the COVID-19 pandemic affected behavioral changes and glycemic control in patients with diabetes and to conduct a survey of telemedicine during the pandemic. Materials and Methods: In this retrospective study, a total of 2,348 patients were included from 15 medical facilities. Patients were surveyed about their lifestyle changes and attitudes toward telemedicine. Hemoglobin A1c (HbA1c) levels were compared among before (from June 1 to August 31, 2019) and in the first (from June 1 to August 31, 2020) and in the second (from June 1 to August 31, 2021) year of the pandemic. A survey of physician attitudes toward telemedicine was also conducted. Results: The HbA1c levels were comparable between 2019 (7.27 ± 0.97%), 2020 (7.28 ± 0.92%), and 2021 (7.25 ± 0.94%) without statistical difference between each of those 3 years. Prescriptions for diabetes medications increased during the period. The frequency of eating out was drastically reduced (51.7% in 2019; 30.1% in 2020), and physical activity decreased during the pandemic (48.1% in 2019; 41.4% in 2020; 43.3% in 2021). Both patients and physicians cited increased convenience and reduced risk of infection as their expectations for telemedicine, while the lack of physician–patient interaction and the impossibility of consultation and examination were cited as sources of concern. Conclusions: Our data suggest that glycemic control did not deteriorate during the COVID-19 pandemic with appropriate intensification of diabetes treatment in patients with diabetes who continued to attend specialized diabetes care facilities, and that patients and physicians shared the same expectations and concerns about telemedicine

Aging and Deflation from a Fiscal Perspective

Negative correlations between inflation and demographic aging were observed across developed nations recently. To understand the phenomenon from a politico-economic perspective, we embed the fiscal theory of the price level into an overlapping-generations model. In the model, successive short-lived governments choose income tax rates and bond issues considering the political influence of existing generations and the policy response of future governments. The model sheds new light on the traditional debate about the burden of national debt. Because of price adjustments, the accumulation of government debt does not become a burden on future generations. Our analysis reveals that the effects of aging depend on its causes. Aging is deflationary when caused by an increase in longevity but inflationary when caused by a decline in birth rate. Numerical simulation shows that aging over the past 40 years in Japan generated deflation of about 0.6 percentage points annually