On the Public Economics of Casino Gambling

This paper studies casino-style gambling from the public economics point of view in a jurisdiction populated by oligopolistically competitive legal casinos. We consider three different regimes: laissez-faire, entry regulation and tax regulation. The model highlights three important external effects from casino-style gambling: non-casino income creation, social disorder costs, and casino exporting to other jurisdictions. In the generalized case with an endogenously-determined ratio of local to total gamblers, we allow the configuration of casinos to be centralized or jurisdiction-wide dispersed. A complete comparison between equilibrium and command optimum outcomes is provided, and the welfare consequences under the three regimes and two casino configurations are examined.Casino gambling, externalities, oligopoly pricing, entry, tax regulation

A Study of MIS Scholar Community Development via a Collaboration Network Structures Analysis

The objective of this study is to apply collaborative networks to understanding the development process of the Management Information System (MIS) journals’ knowledge community. This research explores four phenomena: whether a co-author network depends on star collaborators, whether this network is a small world, the structural cohesion within the co-author network, and central scholars. We found that the MIS community has a small-world structure and high structural cohesion, so the MIS network is a dense cluster. Another finding was that a small number of researchers receive disproportionate recognition in MIS communities, indicating the presence of preferential attachment. This means that the MIS network contains clear star authors. Furthermore, we infer how a structural network affects knowledge diffusion and information diffusion. In addition, this study discusses changes in each journal’s central scholars to observe patterns of publication for each journal published by a private for-profit organization or sponsored by academic societies

The Effect Of Market Structure On Mutual Fund Performance In Taiwan

This paper illustrates the relationship between industry concentration and performance in Taiwan’s mutual fund industry. Our research mainly focuses on the relation between a fund’s average performance and market structure. Typically, a fund’s manager who faces price uncertainty will dedicate his efforts to determine the scale and compositions of portfolio to achieve a better performance in the near future. Since mutual funds are price takers, the empirical results for this industry may go beyond the scope of the SCP paradigm.   This study focuses on the open-end equity mutual fund in the Taiwan market, which can be viewed as one representative of emerging markets. Employing three measures of market structure, we find that the higher degree of market concentration always associates with poor performance, which contradicts the structure-conduct-performance (SCP) hypothesis. More interestingly, when market shares of mutual funds have been considered, our empirical results show a U-shape structure-performance relation for mutual funds. When a fund’s market share becomes larger, the negative influence on fund performance of market concentration will get stronger. Similarly, the smaller a fund’s market share the stronger negative impact on fund performance of market concentration, suggesting that mutual funds endowed with too weak or too strong market power can erode their performance. More importantly, these results offer a new thinking toward the mutual fund industry’s organization policy for authorities; that is, maintaining a high competitive environment and encouraging mutual funds to keep moderate and efficient scale is a better way to achieve superior fund performance

Modeling of minimum void ratio for sand–silt mixtures

Minimum void ratio or maximum packing density is an important soil property in geotechnical engineering. It correlates to the volume change tendency, the pore fluid conductivity, and the shear strength of the soil. In geotechnical engineering, it often requires to estimate the minimum void ratio for a sand–silt mixture with any amount of fines content, based only on few laboratory test results. The minimum void ratio for soil mixtures is usually estimated by methods based on, to some extent, an empirical approach, for example, the AASHTO coarse particle correction method. In this paper, based on a more fundamental approach using the concept of dominant particle network, we aim to develop a mathematical model that can predict the minimum void ratio for sand–silt mixtures with any amount of fines content. The developed model only requires two parameters for the prediction of minimum void ratios of soil mixtures with various fines contents. The developed model is evaluated by the experimental results on 33 types of soil mixtures available in the literature, including mixtures of sands (Ottawa sand, Nevada sand, Toyoura sand, Hokksund sand, etc), and silts (ATC silt, Nevada fines, crushed silica fines, grind Toyoura fines, etc). Comparisons of the results are discussed

Towards understanding the electronic structure of Fe-doped CeO2 nanoparticles with X-ray spectroscopy

[[abstract]]This study reports on the electronic structure of Fe-doped CeO2 nanoparticles (NPs), determined by coupled X-ray absorption spectroscopy and X-ray emission spectroscopy. A comparison of the local electronic structure around the Ce site with that around the Fe site indicates that the Fe substitutes for the Ce. The oxygen K-edge spectra that originated from the hybridization between cerium 4f and oxygen 2p states are sensitive to the oxidation state and depend strongly on the concentration of Fe doping. The Ce M4,5-edges and the Fe L2,3-edges reveal the variations of the charge states of Ce and Fe upon doping, respectively. The band gap is further obtained from the combined absorption–emission spectrum and decreased upon Fe doping, implying Fe doping introduces vacancies. The oxygen vacancies are induced by Fe doping and the spectrum reveals the charge transfer between Fe and Ce. Fe3+ doping has two major effects on the formation of ferromagnetism in CeO2 nanoparticles. The first, at an Fe content of below 5%, is that the formation of Fe3+–Vo–Ce3+ introduces oxygen deficiencies favoring ferromagnetism. The other, at an Fe content of over 5%, is the formation of Fe3+–Vo–Fe3+, which favors antiferromagnetism, reducing the Ms. The defect structures Fe3+–Vo–Ce3+ and Fe3+–Vo–Fe3+ are crucial to the magnetism in these NPs and the change in Ms can be described as the effect of competitive interactions of magnetic polarons and paired ions.[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子

Effects of natto extract on endothelial injury in a rat model

Vascular endothelial damage has been found to be associated with thrombus formation, which is considered to be a risk factor for cardiovascular disease. A diet of natto leads to a low prevalence of cardiovascular disease. The aim of the present study was to investigate the effects of natto extract on vascular endothelia damage with exposure to laser irradiation. Endothelial damage both in vitro and in vivo was induced by irradiation of rose bengal using a DPSS green laser. Cell viability was determined by MTS assay, and the intimal thickening was verified by a histological approach. The antioxidant content of natto extract was determined for the free radical scavenging activity. Endothelial cells were injured in the presence of rose bengal irradiated in a dose-dependent manner. Natto extract exhibits high levels of antioxidant activity compared with purified natto kinase. Apoptosis of laser-injured endothelial cells was significantly reduced in the presence of natto extract. Both the natto extract and natto kinase suppressed intimal thickening in rats with endothelial injury. The present findings suggest that natto extract suppresses vessel thickening as a synergic effect attributed to its antioxidant and anti-apoptosis properties