bluuebunny/crossref_metadata_2025 huggingface dataset:
Intrinsic spectrally-dependent background in spectroscopic visible-light optical coherence tomography
Authors: Rubinoff Ian , Kuranov Roman V. , Zhang Hao F.
Published: September 2020

Visible-light optical coherence tomography (vis-OCT) enabled new spectroscopic applications, such as retinal oximetry, as a result of increased optical absorption and scattering contacts in biological tissue and improved axial resolution. Besides extracting tissue properties from back-scattered light, spectroscopic analyses must consider spectral alterations induced by image reconstruction itself. We investigated an intrinsic spectral bias in the background noise floor, which is hereby referred to as the spectrally-dependent background (SDBG). We developed an analytical model to predict the SDBG-induced bias and validated this model using numerically simulated and experimentally acquired data. We found that SDBG systemically altered the measured spectra of blood in human retinal vessels in vis-OCT, as compared to literature data. We provided solutions to quantify and compensate for SDBG in retinal oximetry. This work is particularly significant for clinical applications of vis-OCT.
Tripartite holobiont system in a vent snail broadens the concept of chemosymbiosis
Authors: Yang Yi , Sun Jin , Chen Chong , Zhou Yadong , Lan Yi , Van Dover Cindy Lee , Wang Chunsheng , Qiu Jian-Wen , Qian Pei-Yuan
Published: September 2020

Many animals inhabiting deep-sea vents are energetically dependent on chemosynthetic endosymbionts, but how such symbiont community interacts with host, and whether other nutritional sources are available to such animals remain unclear. To reveal the genomic basis of symbiosis in the vent snailAlviniconcha marisindica, we sequenced high-quality genomes of the host and gill campylobacterial endosymbionts, as well as metagenome of the gut microbiome. The gill endosymbiont has a streamlined genome for efficient chemoautotrophy, but also shows metabolic heterogeneity among populations. Inter- and intra-host variabilities among endosymbiont populations indicate the host poses low selection on gill endosymbionts. Virulence factors and genomic plasticity of the endosymbiont provide advantages for cooperating with host immunity to maintain mutualism and thriving in changing environments. In addition to endosymbiosis, the gut and its microbiome expand the holobiont’s utilisation of energy sources. Host-microbiota mutualism contributes to a highly flexible holobiont that can excel in various extreme environments.
Semiconducting bacterial biofilm based on graphene-MoS2 template and component dependent gating behavior
Authors: Ray Sanhita , Das Arpita , Dasgupta Anjan Kr
Published: September 2020

In this paper, we report for the first time, the synthesis of a semiconducting biofilm. Photosynthetic bacterial biofilm has been used to weave together MoS2 nanosheets into an adherent film grown on interdigitated electrodes. Liquid-phase exfoliation of bulk MoS2 powder was used to obtain MoS2 nanosheets. A synchronous-fluorescence scan revealed the presence of two emission maxima at 682nm and 715nm for the MoS2 suspension. Such maxima with bandgap energy 1.82 and 1.73 eV corresponded to the single and double layer of MoS2. The presence of such single and multi-layered structures was confirmed by Raman spectroscopy, FTIR studies, and electron microscopy. The current-voltage (I-V) studies of such a bio-nano hybrid revealed the emergence of the gated nature of the current flow. This Schottky diode like behavior, reported earlier for Graphene-biofilm junctions, is also observed in this case. Gating voltage depended on the composition of the biofilm. The semiconductor biofilms, when studied using electrochemical impedance spectroscopy, revealed characteristic Nyquist and Bode plots, suggesting special circuit-equivalence for each film. While Mos2 was marked with stability with respect to variations in RMS voltage and bias voltage, the graphene biofilm was unique by the absence of any Warburg element.
Mpl is activated by dimers of MPN-linked calreticulin mutants stabilized by disulfide bonds and ionic interactions
Authors: Venkatesan Arunkumar , Geng Jie , Kandarpa Malathi , Wijeyesakere Sanjeeva Joseph , Bhide Ashwini , Talpaz Moshe , Pogozheva Irina D. , Raghavan Malini
Published: September 2020

Myeloproliferative neoplasms (MPNs) are frequently driven by insertions and deletions within the gene encoding calreticulin (CRT). CRTDel52and CRTIns5are recurrent mutations. Although oncogenic transformation requires both mutated CRT and the myeloproliferative leukemia protein (Mpl), the molecular mechanism of CRT-mediated constitutive activation of Mpl is unknown. Our studies reveal that the novel C-domain of CRTDel52encodes specificity both for Mpl binding and for disulfide-mediated CRT dimerization. Disulfide-stabilized CRTDel52dimers and multimers are observed in MPN patient-derived platelet lysates and in transfected mammalian cells. Cysteine mutations within both the novel C-domain (C400A and C404A) and the conserved N-domain (C163A) of CRTDel52are required to reduce disulfide-mediated dimers and multimers of CRTDel52. Based on these data and published structures of crystalized CRT oligomers, we tested the relevance of ionic interactions between charged residues proximal to C163 at the N-domain dimerization interface. Charge alteration at these residues affected dimerization and multimerization of both wild type and CRTDel52. Elimination of intermolecular disulfides and disruption of ionic interactions at both proposed dimerization interfaces was required to abrogate the ability of CRTDel52to induce cytokine-independent cell proliferation via Mpl. Based on these findings, we propose a structural model of the Mpl-activating CRTDel52unit as a covalently-linked dimer that is stabilized by disulfides and ionic interactions at both the C-domain and N-domain. MPNs exploit a natural dimerization interface of CRT combined with C-domain gain-of-functions to achieve cell transformation.
Phase analysis for partially coherent light propagating through an optimized aperture in a synchrotron beamline
Authors: Ren Junchao , Meng Xiangyu , Wang Yong , Cao Jiefeng , Li Junqin , Tai Renzhong
Published: September 2020

The mutual optical intensity propagation of partially coherent light through a beamline is calculated for different aperture sizes and positions. The coherence, intensity and phase distribution can be extracted from the mutual optical intensity. The phase distribution depends on the aperture size and position. The results show that the widest flat phase distribution is obtained at the optimized aperture size and position. The aperture plays a more important role for partially coherent light than for incoherent light. The influence of the aperture size and position on the intensity and spot size at the focal plane is also analyzed. A way to obtain a balance between the flat phase distribution area, spot size and intensity for partially coherent light in the beamline is demonstrated.
The consumption of live music in different languages: a quantitative approach
Authors: Spanu Michael , Sommet Nicolas , Seca Jean-Marie
Published: September 2020

Purpose

The consumption of music performed in different languages represents a significant aspect of the contemporary cultural experience. This phenomenon questions how different languages mediate music consumption in specific national contexts. In this paper, the authors investigate the case of live music consumption in France.

Design/methodology/approach

The authors surveyed 428 persons who saw 159 artists either performing in French or in English in 46 locations around Paris, France. The authors tested the effect of the language of the concert on three dimensions of music consumption: singing in unison, appraisal of the lyrics and dancing.

Findings

Multilevel analysis revealed that English was positively associated with dancing, whereas French was positively associated with the appraisal of the lyrics. The authors found no evidence that the language of the concert was associated with differences in singing in unison.

Originality/value

Results are discussed with respect to language diversity in the context of globalised popular music consumption.
Trading Performance of Domestic and Foreign Investors in KOSPI200 Index Futures Markets
Authors: Kho Bong-Chan , Kim Jin-Woo
Published: September 2020

We analyze trading performance of domestic and foreign investors in the KOSPI200 index futures markets in Korea over various holding periods from each transaction time to 20 trading days. We find that foreign non-brokerage firms (including investment trust, pension fund, bank and insurance) trade at a disadvantageous price compared to domestic investors, i.e., buying at a higher price by about 5bp and selling at a lower price by about 6bp during the sample period (May 1996∼Dec. 1999). The magnitude of the disadvantageous price is close to the opportunity loss attributable to their intraday momentum strategy. In contrast, foreign brokerage firms trade at a somewhat advantageous price relative to domestic investors, but not always do so. By extending holding periods up to 20 trading days after each trade, we find that foreign investors and domestic brokerage firms who made large buy or sell trades show significantly higher holding period returns, indicating that they possess superior ability to predict future price movements.
The Impact of Program Trading on the Short-run and Long-run Volatility of Korean Stock Market
Authors: Hahn Sang Buhm , Oh Seung Hyun
Published: September 2020

This study investigates the impact of program trading on the market volatility by separating the volatility into long-run and short-run components using VA-CEGARCH model. This approach allows us to observe the two channels through which the program trading affects the market volatility. We have following results. Program trading and non-program trading both have no impact on the long-run component but do increase short-run component. In case of short-run component‘ program trading has a larger impact compared to non-program trading. Secondly, in both daily and intra-day analysis, arbitrage program trading is found to have a larger impact on short-run components than non-arbitrage program trading.

Thirdly, ARCH effects are found in short-run components of daily analysis and long-run components of intra-day analysis. And the volatility’s asymmetric responses to good or bad news are introduced through long-run components. What is noteworthy is the fact that non-arbitrage program trading is actually found to reduce short-run volatility in the intra-day analysis.

Which means that non-arbitrage program trading, such as hedging transactions, helps promote intra-day market stability. Our findings mean that the short-run component is the main channel by which program trading produce unnecessary market volatility.
Stock Return Volatility and Corporate Credit Risk
Authors: Jeong Wan-Ho , Kook Chan-Pyo
Published: September 2020

In order to reinforce traditional credit indicators such as credit rate or financial ratio, many financial market data; such as the stock prices or their returns are used to evaluate corporate credit risk. Even though many structural models, which are using stock returns and their volatilities, are used to measure credit risk, empirical studies to find out how to measure desirable stock return volatility or which interval data is better for measuring the volatility are not enough.

So, we tried to find out empirical evidences of following two questions. First, whether stock return volatility could be used as a timely indicator for credit events, such as bankruptcy or credit rate change. Second, which measure and which interval data are the best to calculate stock return volatility for credit indicator.

We have reached the following empirical conclusions based on recent Korean stock market data. First, stock return volatility could be useful for early warning of credit events, because the volatility showed meaningful increase before the credit event. Second, 90~150 daily stock return data are useful to measure the volatility. Short-term data, less than 90 days are too sensitive to market circumstances and they easily increase without any credit level change. On the contrary, volatilities based on long-term data, more than 150 days are too smooth to use as a timely credit indicator. Third, in aspect of the measure of volatility, realized volatility which assume the averages of short-term stock returns are ‘zero’ is more efficient than traditional standard deviation.

Those conclusions are based on recent Korean stock market data, so further robustness test should be followed.
Regime Dependent Determinants of Credit Default Swap Spread
Authors: Kim Hong-Bae , Lee Yeonjeong , Kang Sang Hoon , Yoon Seong-Min
Published: September 2020

This study investigates the influence of theoretical determinants on the Korea sovereign CDS spreads from January 2007 to September 2009 based on structural credit risk model. For the analysis of determinants on the sovereign CDS spread, this study adopts interest swap rate as reference interest rate, and decomposes yields curve into two components, ie, interest level and slope. Considering multivariate regression in level and difference variables, Stock returns and Interest rates have a significant effect on the CDS spreads among the theoretical determinants of structural credit risk models. CDS spreads may behave quite differently during volatile regime compared with their behavior in tranquil regime. We therefore apply Markov switching model to investigate the possibility that the influence of theoretical determinants of CDS spread has a regime dependent behavior. In all regimes Korean sovereign CDS spreads are highly sensitive to stock market returns, whereas in tranquil regime interest rates also have influence on CDS spreads. We conclude that for the efficient hedging of CDS exposure trader should adjust equity hedge ratio to the relevant regime.
Information Transmission between Nighttime Trading and Daytime Trading: Evidence from KOSPI 200 Futures
Authors: Lee Woo-Baik
Published: September 2020

Trading of KOSPI 200 futures on CME Globex platform, which was launched in November 2009, starts at 18:00 and closes at 05:00 in the next morning. This paper investigates the information transmission between daytime trading of KOSPI 200 futures on KRX and nighttime trading of KOSPI 200 futures on CME Globex by using GARCH (1, 1).

The main findings of this paper are summarized as followings; Firstly, the statistically significant spillover effect from open-to-close returns of KOSPI 200 Futures on Globex to the overnight returns of KOSPI 200 futures on KRX is found but not to the daytime returns. Moreover, I find the spillover effects from daytime returns of KOSPI 200 futures on KRX to close-to-open return and open-to-close return of KOSPI 200 Futures on Globex. Meanwhile, this information transmission between two markets of common underlying asset shows more strongly statistical significance during highly liquid period. Secondly, daytime traders of KOSPI 200 futures on KRX recognize the price of KOSPI 200 futures on CME Globex as more valuable information than volatility of US stock market. Overall empirical evidence suggests that KOSPI 200 futures on CME Globex has leading role in price discovery process of daytime trading of KOSPI 200 futures on KRX despite of immaturity and low liquidity.
Laeding and Following Variance Risk Premiums: Evidence from S&P500 and KOSPI200 Options
Authors: Yoon Sun-Joong , Kim Jun Sik
Published: September 2020

This study aims to examine the return predictability of variance risk premium, which is defined as the difference between risk-neutral variance and expected realized variance, on KOSPI 200 index returns. Although extant literature shows that variance risk premium estimated from U.S. index options has a predictive power on underlying returns, little study has been conducted in KOSPI 200 index returns. In addition, there is no conclusion for the predictive power of variance risk premium in other financial markets. In this paper, we can find the predictive power of S&P500 variance risk premium on KOSPI200 index returns as well as on S&P500 index returns, but cannot find the predictive power of KOSPI200 variance risk premium on both indices. These results are consistent to Londono (2012) and Bollerslev et al. (2013). The poor performance of KOSPI200 variance risk premium is explained by the assumption that U.S. economy is a leader economy, while Korea economy is a follower economy. To support this conclusion, we conduct Vector Auto-Regression (VAR) using two variance risk premiums. Two premiums have bi-directional lead-lag relationship but S&P500 variance risk premium is informationally superior to KOSPI200 variance risk premium regarding return predictions.
The Impact of Structural Breaks on Volatility Linkages between Asian Stock and Oil Futures Markets
Authors: Kang Sang Hoon , Yoon Seong-Min
Published: September 2020

This paper investigates the impact of structural breaks on volatility spillovers between Asian stock markets (China, Hong Kong, India, Indonesia, Japan, Korea, Singapore, and Taiwan) and the oil futures market. To this end, we apply the bivariate DCC-GARCH model to weekly spot indices during the period 1998-2015. The results reveal significant volatility transmission for the pairs between the Asian stock and oil futures markets. Moreover, we find a significant variability in the time-varying conditional correlations between the considered markets during both bullish and bearish markets, particularly from early 2007 to the summer of 2008. Using the modified ICSS algorithm, we find several sudden changes in these markets with a common break date centred on September 15, 2008. This date corresponds to the collapse of Lehman Brothers which is considered as our breakpoint to define the global financial crisis. Also, we analyse the optimal portfolio weights and time-varying hedge ratios based on the estimates of the multivariate DCC-GARCH model. The results emphasize the importance of overweighting optimal portfolios between Asian stock and the oil futures markets.
The Impact of Credit Rating Change on Investor Sentiment
Authors: Ryu Doojin , Kim Karam , Yang Heejin
Published: September 2020

The behavioral finance literature focuses on the effect of investor sentiment on the fundamental values of individual stocks. This study constructs a firm-level investor sentiment indicator based on transaction and price data for individual firms and shows that credit rating changes affect investor sentiment. We find the following empirical results. First, the response of investor sentiment to upgrades (downgrades) is significantly positive (negative). Second, the greater the magnitude of the downgrade is, the more negative the investor sentiment reaction is, although we do not find a similar result for upgrades. Third, cumulative abnormal returns around the event day are affected by cumulative abnormal sentiment before that day. This result suggests that the market reaction is affected by a combination of credit rating downgrades and investor sentiment.
Which One is More Important Factor for Pricing Options, Skewness or Kurtosis?
Authors: Kim Sol
Published: September 2020

This paper investigates the relative importance of the skewness and kurtosis of the risk neutral distribution for pricing KOSPI200 options. The skewness and kurtosis are estimated from non parametric method of Bakshi, Kapadia, and Madan (2003) and the parametric method of Corrado and Su (1996). We show that the skewness of the risk neutral distribution is more important factor than the kurtosis irrespective of the estimation method, the definition of pricing errors, the moneyness, the type of options and a period of time.
The Effects of Corporate Governance on CEO Compensation
Authors: Lee Myoung Gi , Kim Jin San
Published: September 2020

The purpose of this study is to find the effects of corporate governance on executive compensation using the sample of Korean manufacturing firms listed on the Korea Exchange (KRX) from 2005 to 2012. In order to do that, this study extends empirical models of Core et al. (1999), Fahlenbrach (2009), Giroud and Mueller (2011), and finds the following results. First, internal corporate governance negatively affects executive compensation, implying that a good corporate governance can prevent outrageous compensation to top executives with poor performance. On the other hand, the interactions between internal and external corporate governance mechanisms have mixed results. While the first interaction has little impact on executive compensation, the second interaction among three different mechanisms has a positive and statistically significant impact. These results imply that while internal corporate governance and product market competition works against executive compensation, labor union may be in the same boat with managers in terms of compensation. Unlike most previous studies based on one-dimensional approach, this study investigates interactions among various corporate governance mechanisms. Overall results have a few important economic and social implications. Because internal corporate governance works as an effective mechanism, policymakers should find ways to make internal control mechanisms as independent as possible.
A Study on the Price Discovery in Korea Stock Index Markets: KODEX200, KOSPI200, and KOSPI200 Futures
Authors: Kang Seok-Kyu
Published: September 2020

This paper examines the price discovery process among the Korea stock index markets using the vector error correction model (VECM) and the multivariate generalized auto regressive conditional heteroskedasticity (M-GARCH) model. The minute-by-minute price series of the KOSPI200 index, KOSPI200 futures, and KODEX200 are cointegrated.

The empirical results are summarized as follows: First, VECM estimation results indicate that when the cointegrating relationship is perturbed by the arrival of ntis, the KODEX200(ETF) does not adjusted to restore equilibrium. This is the task of the KOSPI200 futures and spot. These two index securities use the KODEX200 to represent the ntioequilibrium price, with the KOSPI200 futures responding faster than the KOSPI200 spot. When the cointegrating relationship betweeiesOSPI200 spot and futues is perturbed by the arrival of ntis, the KOSPI200 spot does adjusted to restore equilibrium. Next, the results from the multivariate GARCH modes indicate that the volatilities of esOSPI200 spot and futures markets suggest unidirectiona1volatility spillover from KOSPI200 futures to KOSPI200 spot. KODEX200(ETF) volatilities spill over bothesOSPI200 spot and futures markets. and this happen in the reverse direction with a strong effect from the KODEX200 to KOSP200 futures and spot.

The overall findings indicate that the KODEX200(ETF) market dominates KOSPI200 futures and spot in the price discovery process. The regulation of Instutional traders on trading on futures markets explains its superior price discovery function.
The Information in Credit Default Swap Volume
Authors: Lee Dongyoup
Published: September 2020

This article examines the informational content of credit default swap (CDS) net notional for future stock and CDS prices. Using the information on CDS contracts registered in DTCC, a clearinghouse, I construct CDS-to-debt ratios from net notional, that is, the sum of net positive positions of all market participants, and total outstanding debt issued by the reference entity. Unlike the ratio using the sum of all outstanding CDS contracts, this ratio directly indicates how much of debt is insured with CDS and therefore, is a natural measure of investors’ concern on a credit event of the reference entity. Empirically, I find crosssectional evidence that the current increase in CDS-to-debt ratios can predict a decrease in stock prices and an increase in CDS premia of the reference firms in the next week. Greater predictability for firms with investment grade credit ratings or low CDS-to-debt ratios suggests that investors pay more attention to firms in good credit conditions than those regarded as junk or already insured considerably with CDS.
Research on the American Call Options on the Stocks Paying Multiple Dividends
Authors: Bae Kwangil
Published: September 2020

Cassimon et al. (2007) propose a pricing formula of American call options under the multiple dividends by extending Roll (1977). However, because these studies investigate the option pricing formula under the escrow model, there is inconsistency for the assumption of the stock prices. This paper proposes pricing formulas of American call options under the multiple dividends and piecewise geometric Brownian motion. For the formulas, I approximate the log prices of ex-dividend dates to follow a multivariate normal distribution, and decompose the option price as a function of payoffs and exercise boundaries. Then, I obtain an upper bound of the American call options by substituting approximated log prices into the both of the payoffs and the exercise boundaries. Besides, I obtain a lower bound of the price by substituting approximated price only into the exercise boundaries. These upper and lower bounds are exact prices when the amounts of dividends are linear to the stock prices. According to the numerical study, the lower bound produces relatively small errors. Especially, it produces small errors when the dividends are more sensitive to the stock price changes.
Price Momentum in Korea and the Effect of Investors’ Trading
Authors: Lee Kyoim
Published: September 2020

This study investigates domestic individual, institutional and foreign investors’ trading, to test Hong and Stein (1999)’s behavioral explanation that momentum profit is generated as some uninformed investors underreact to information on medium-term prices. Using Hvidkjaer (2006)’s methodology, we examine the respective investors’ trading tendencies reflected in their active price-setting orders. We analyze a special database compiling details on every transaction for the stocks listed on the KSE during 1996:12~2009:08. During 2001~2007, individual investors’ underreaction in trading large-size winner stocks contributes to positive momentum profits. They seem to induce weak negative profits to emerge in 1997~2000, too. Foreign investors underreact to small-size loser stocks, incurring positive momentum profits during 2001~2007. They engage in positive feedback trading, when they trade large-size winner stocks. This trading tendency does not seem to be based on information on firm fundamentals, as we find those winner stocks’ returns are not sustained. Institutional investors’ trading seems to be relatively in line with future returns, but evidences are not strong enough to support they are informed investors. Overall, the behavioral hypothesis on investors’ underreaction seems to explain medium-term momentum profits in Korea, but evidences differing across subsamples suggest possibility of other unknown influences.
Derivatives Use, Firm Value, Risk and Determinants: Evidence of Korean Firms
Authors: Kwon Taek Ho , Park Rae Soo , Chang Uk
Published: September 2020

In this paper we analyze the incentives of derivatives usage and its effect on the risk management and value of firms in Korea. We find that Korean non-financial firms use derivatives not only by the economic incentives to hedge risks but also by the irrational incentives such as the profitability of derivative usage in the previous year. Further results show that the usage of derivatives has a negative effect on the risk management of the firm, which results in the decrease of the firm value. These results show that investors have doubt about the incentives and the effects of derivatives usage in Korea.
Complexity, Knowledge Asymmetry, and Monopolistic Competition The Case of Retail Structured Product Market
Authors: Liu Won-Suk , Choi Young-Min
Published: September 2020

This paper introduces a monopolistic competition model containing retail investors with imperfect knowledge and issuers offering complex structured products. The model, for which we provide empirical evidences supporting the issuer’s profiteering by increasing the product complexity, can explain that knowledge asymmetry is the key for the issuer to offer complex product and to enjoy the higher excess profit, thus worsening allocative efficiency. Our empirical analysis reports monotonically increasing mark-up premia, and J-shaped issue amounts with respect to complexity: the former result could be explained in a rational framework considering issuer costs, however, the latter is not the case. Our model proves the empirical results are well explained when knowledge asymmetry between issuer and investors is a strictly increasing convex function of complexity.
Determinants of the Index Straddle Returns
Authors: Kang Byung Jin
Published: September 2020

This paper investigates ATM zero-beta straddle (i.e., ZBS) returns, one of the most widely used volatility trading strategies, and then examines the determinants of them. First, from a point of theoretical view, we find that the determinants of the ZBS returns without rebalancing are different from those with rebalancing. This means that most previous studies overlooking the return characteristics by difference of rebalancing frequency could result in misleading implications. Next, from a point of empirical view, we find that the negative excess returns are also obtained by taking a long position in ZBS on the KOSPI 200 index options, as in most other markets. Even though these negative excess returns are not strongly significant, but they are found to be closely related to the volatility risk premium.
Modelling the synergy between fiscal incentives and foreign direct investment in Ghana
Authors: Abille Adamu Braimah , Mpuure Desmond Mbe-Nyire , Wuni Ibrahim Yahaya , Dadzie Peter
Published: September 2020

Purpose

The purpose of the paper was to investigate the role of fiscal incentives in driving foreign direct investment (FDI) inflows into the Ghanaian economy based on data from 1975 to 2017 with the Eclectic paradigm as the theoretical basis. FDI inflows was the dependent variable whiles trade openness, corporate tax rate, exchange rate and market size were the independent variables with corporate tax rate as the main explanatory variable of interest.

Design/methodology/approach

The autoregressive distributed lag (ARDL) bounds test technique was employed to investigate Cointegration in the model. The results showed the presence of cointegration among the variables.

Findings

The results revealed that corporate tax rates have a significant negative impact on FDI inflows into the Ghanaian economy in the long run and significant positive impact on FDI inflows in the short run. In the context of Ghana, the positive short-run relationship observed is attributed to the lag effect of tax policy on FDI inflows.

Research limitations/implications

One obvious limitation of the research is that, it does not identify the specific foreign businesses that are more deserving of a low corporate rate and to what extent can that boost FDI inflows in Ghana. Another limitation is that the data analyzed in the paper is exclusively for Ghana and the findings may not be generalized for other countries.

Practical implications

Based on the research findings, it is recommended that the Ghana Revenue Service (GRA) restructures the corporate tax regime in the country to deal with the policy lapses. It is also recommended that low corporate rates should be maintained especially in respect of foreign companies that are into the production of goods and services for which indigenous companies in Ghana have a comparative disadvantage in order to drive FDI into the Ghanaian economy.

Originality/value

This paper is unique for providing up to date and dynamic insights into the tax incentive and FDI nexus in the Ghanaian context.
Functional role of bioactive peptides with special reference to cheeses
Authors: Rafiq Saima , Gulzar Nabila , Sameen Aysha , Huma Nuzhat , Hayat Imran , Ijaz Raina
Published: September 2020

Growing perception about diet in relation to health has extended the necessity to explore the biologically active components present in native foods. In this review, bioactive peptides released from cheeses that may have important physiological functions are discussed. Bioactive encrypted peptides can be generated from precursor milk proteins during food processing via enzymatic hydrolysis and fermentation. Generally, biofunctionalities of peptides are latent within precursor proteins. Bioactive peptides liberated from cheeses exhibit numerous potential therapeutic roles: for example, angiotensinogen‐converting enzyme (ACE) inhibition, antioxidant, anti‐thrombotic, anti‐microbial, anti‐cancer and anti‐inflammatory. This article critically focuses on the functional roles of bioactive peptides derived from different cheeses.
Overwork, job embeddedness and turnover intention among Chinese knowledge workers
Authors: Huang Hongwei , Xia Xue , Zhao Wenxi , Pan Xiaoqing , Zhou Xiaoqiang
Published: September 2020

A growing number of scholars are beginning to pay attention to the problems caused by overwork of knowledge workers. Overwork affects the health of workers in general, and has a variety of specific effects on the work of knowledge workers. This paper explores how overworking correlates with turnover intention among knowledge workers in China, and how job embeddedness acts as an intermediary factor in the role of overwork in the demission of knowledge workers. Using the data of 967 knowledge workers across 17 provinces in China, the research conducted a stepwise testing of linear regression coefficients followed by a bootstrap validation, and discovered a positive correlation between overwork and the turnover intention of knowledge workers, with job embeddedness demonstrating a significant intermediary effect. Overwork will reduce the job embeddedness of knowledge workers, thus increasing their turnover intention. Little attention has been paid to the effect of overwork on the turnover intentions of knowledge workers in China. Our research will contribute to understandings of the overwork of knowledge workers in Chinese culture. and suggest to human resource managers more rational and sustainable arrangements of the working hours of knowledge workers.
Vascular amyloid accumulation alters the gabaergic synapse and induces hyperactivity in a model of cerebral amyloid angiopathy
Authors: Cisternas Pablo , Taylor Xavier , Perkins Abigail , Maldonado Orlando , Allman Elysabeth , Cordova Ricardo , Marambio Yamil , Munoz Braulio , Pennington Taylor , Xiang Shunian , Zhang Jie , Vidal Ruben , Atwood Brady , Lasagna‐Reeves Cristian A.
Published: September 2020

Cerebral amyloid angiopathy (CAA) is typified by the cerebrovascular deposition of amyloid. The mechanisms underlying the contribution of CAA to neurodegeneration are not currently understood. Although CAA is highly associated with the accumulation of β‐amyloid (Aβ), other amyloids are known to associate with the vasculature. Alzheimer's disease (AD) is characterized by parenchymal Aβ deposition and intracellular accumulation of tau as neurofibrillary tangles (NFTs), affecting synapses directly, leading to behavioral and physical impairment. CAA increases with age and is present in 70%–97% of individuals with AD. Studies have overwhelmingly focused on the connection between parenchymal amyloid accumulation and synaptotoxicity; thus, the contribution of vascular amyloid is mostly understudied. Here, synaptic alterations induced by vascular amyloid accumulation and their behavioral consequences were characterized using a mouse model of Familial Danish dementia (FDD), a neurodegenerative disease characterized by the accumulation of Danish amyloid (ADan) in the vasculature. The mouse model (Tg‐FDD) displays a hyperactive phenotype that potentially arises from impairment in the GABAergic synapses, as determined by electrophysiological analysis. We demonstrated that the disruption of GABAergic synapse organization causes this impairment and provided evidence that GABAergic synapses are impaired in patients with CAA pathology. Understanding the mechanism that CAA contributes to synaptic dysfunction in AD‐related dementias is of critical importance for developing future therapeutic interventions.
Clinical manifestations and maternal and perinatal outcomes with COVID‐19
Authors: Li Wei , Yu Nan , Kang Qingling , Zeng Wanjiang , Deng Dongrui , Chen Suhua , Feng Ling , Wu Jianli
Published: September 2020

Coronavirus disease 2019 (COVID‐19) is a novel type of highly contagious pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). As the COVID‐19 outbreak unfolds, more and more pregnant women are infected with SARS‐CoV‐2, concerns have been raised about its clinical manifestations in pregnancy and the potential risk of vertical transmission from mother to fetus in pregnant women. Hence, in this review, we summarize the latest research progress related to COVID‐19 epidemiology and the reported data of pregnant women with COVID‐19 and discuss the clinical manifestations, treatments, maternal and perinatal outcomes, and intrauterine vertical transmission potential of such virus. Reported data suggest that symptoms in pregnant women are similar to those in other populations and that there is no evidence of vertical transmission from mother to child. In the meantime, considering the good prognosis of most of the infected mothers and infants and absence of serious obstetric complications in pregnant women with COVID‐19, it is not recommended to give birth as soon as possible, and it is necessary to extend the gestational period reasonably.
Biomarkers for diagnosis and prediction of therapy responses in allergic diseases and asthma
Authors: Breiteneder Heimo , Peng Ya‐Qi , Agache Ioana , Diamant Zuzana , Eiwegger Thomas , Fokkens Wytske J. , Traidl‐Hoffmann Claudia , Nadeau Kari , O'Hehir Robyn E. , O'Mahony Liam , Pfaar Oliver , Torres Maria J. , Wang De‐Yun , Zhang Luo , Akdis Cezmi A.
Published: September 2020

Modern health care requires a proactive and individualized response to diseases, combining precision diagnosis and personalized treatment. Accordingly, the approach to patients with allergic diseases encompasses novel developments in the area of personalized medicine, disease phenotyping and endotyping, and the development and application of reliable biomarkers. A detailed clinical history and physical examination followed by the detection of IgE immunoreactivity against specific allergens still represents the state of the art. However, nowadays, further emphasis focuses on the optimization of diagnostic and therapeutic standards and a large number of studies have been investigating the biomarkers of allergic diseases, including asthma, atopic dermatitis, allergic rhinitis, food allergy, urticaria and anaphylaxis. Various biomarkers have been developed by omics technologies, some of which lead to a better classification of distinct phenotypes or endotypes. The introduction of biologicals to clinical practice increases the need for biomarkers for patient selection, prediction of outcomes and monitoring, to allow for an adequate choice of the duration of these costly and long‐lasting therapies. Escalating healthcare costs together with questions about the efficacy of the current management of allergic diseases require further development of a biomarker‐driven approach. Here, we review biomarkers in diagnosis and treatment of asthma, atopic dermatitis, allergic rhinitis, viral infections, chronic rhinosinusitis, food allergy, drug hypersensitivity and allergen immunotherapy with a special emphasis on specific IgE, the microbiome and the epithelial barrier. In addition, EAACI guidelines on biologicals are discussed within the perspective of biomarkers.
Letter: effectiveness of ustekinumab or vedolizumab in Crohn's disease following anti‐TNF failure—getting closer to the truth?
Authors: Liu Kecheng , Cai Fuqing , Huang Jiean
Published: September 2020

LINKED CONTENT

This article is linked to Biemans et al papers. To view these articles, visit https://doi.org/10.1111/apt.15745 and https://doi.org/10.1111/apt.16062
Diagnostic yield and clinical utility of whole exome sequencing using an automated variant prioritization system, EVIDENCE
Authors: Seo Go Hun , Kim Taeho , Choi In Hee , Park Jung‐young , Lee Jungsul , Kim Sehwan , Won Dhong‐gun , Oh Arum , Lee Yena , Choi Jeongmin , Lee Hajeong , Kang Hee Gyung , Cho Hee Yeon , Cho Min Hyun , Kim Yoon Jeon , Yoon Young Hee , Eun Baik‐Lin , Desnick Robert J. , Keum Changwon , Lee Beom Hee
Published: September 2020

EVIDENCE, an automated variant prioritization system, has been developed to facilitate whole exome sequencing analyses. This study investigated the diagnostic yield of EVIDENCE in patients with suspected genetic disorders. DNA from 330 probands (age range, 0‐68 years) with suspected genetic disorders were subjected to whole exome sequencing. Candidate variants were identified by EVIDENCE and confirmed by testing family members and/or clinical reassessments. EVIDENCE reported a total 228 variants in 200 (60.6%) of the 330 probands. The average number of organs involved per patient was 4.5 ± 5.0. After clinical reassessment and/or family member testing, 167 variants were identified in 141 probands (42.7%), including 105 novel variants. These variants were confirmed as being responsible for 121 genetic disorders. A total of 103 (61.7%) of the 167 variants in 95 patients were classified as pathogenic or probably to be pathogenic before, and 161 (96.4%) variants in 137 patients (41.5%) after, clinical assessment and/or family member testing. Factor associated with a variant being regarded as causative includes similar symptom scores of a gene variant to the phenotype of the patient. This new, automated variant interpretation system facilitated the diagnosis of various genetic diseases with a 42.7% diagnostic yield.
Linking patterns of intraspecific morphology to changing climates
Authors: McGuire Jenny L. , Lauer Daniel A.
Published: September 2020

Aim

This study examines how climate shaped Microtus californicus (Rodentia: Arvicolinae) ecomorphology throughout the Quaternary. It tests three hypotheses: (a) climate corresponds with consistent shape variation in M. californicus dentition; (b) Quaternary warming and drying trends caused M. californicus morphotypes to predictably shift in range through time and (c) Quaternary warming and drying led to predictable changes in tooth morphological variation. Finally, we discuss how shifts in climate‐linked morphological variation may affect the potential of M. californicus to react to future climate change.

Location

Western United States.

Taxon

Microtus californicus (Peale, 1848).

Methods

Geometric morphometrics and partial least squares analyses were used to discern how climate contributes to consistent variation in the shapes of the M. californicus lower first molar (m1), validated for the full toothrow. We further corroborate this relationship, reconstructing precipitation at fossil localities using m1 morphology and comparing those values to palaeoclimate‐model‐derived precipitations. Disparity analyses and a MANOVA were performed to examine changes in variation and whether a shift in tooth shape occurred through time.

Results

Microtus californicus m1 and toothrow shapes are narrower and more curved in cooler, wetter climates. Morphology‐based palaeoclimate reconstructions align with model‐based palaeoclimate estimations. When time averaging is accounted for, M. californicus demonstrates a 12% reduction in variation from fossil to present‐day specimens, and these changes in tooth shape correspond with climate‐related morphotypes.

Main conclusions

As California became drier and hotter since the late Pleistocene, M. californicus dental morphology generally tracked these changes by adapting to the consumption of rougher vegetation in drier environments. This resulted in the loss of some high‐precipitation morphotypes, indicating that ecomorphology, often observed at the species and community levels, translates to intraspecific variation and dynamically changes in response to changing climates. The loss of climate‐linked morphological variation since the late Pleistocene may limit the ability of M. californicus to respond to future changes in climate. These findings portend that other species may have experienced similar losses in adaptability.
Bicuculline regulated protein synthesis is dependent on Homer1 and promotes its interaction with eEF2K through mTORC1‐dependent phosphorylation
Authors: Gladulich Luis F. H. , Xie Jianling , Jensen Kirk B. , Kamei Makoto , Paes‐de‐Carvalho Roberto , Cossenza Marcelo , Proud Christopher G.
Published: September 2020

The regulation of protein synthesis is a vital and finely tuned process in cellular physiology. In neurons, this process is very precisely regulated, as which mRNAs undergo translation is highly dependent on context. One of the most prominent regulators of protein synthesis is the enzyme eukaryotic elongation factor kinase 2 (eEF2K) that regulates the elongation stage of protein synthesis. This kinase and its substrate, eukaryotic elongation factor 2 (eEF2) are important in processes such as neuronal development and synaptic plasticity. eEF2K is regulated by multiple mechanisms including Ca2+‐ions and the mTORC1 signaling pathway, both of which play key roles in neurological processes such as learning and memory. In such settings, the localized control of protein synthesis is of crucial importance. In this work, we sought to investigate how the localization of eEF2K is controlled and the impact of this on protein synthesis in neuronal cells. In this study, we used both SH‐SY5Y neuroblastoma cells and mouse cortical neurons, and pharmacologically and/or genetic approaches to modify eEF2K function. We show that eEF2K activity and localization can be regulated by its binding partner Homer1b/c, a scaffolding protein known for its participation in calcium‐regulated signaling pathways. Furthermore, our results indicate that this interaction is regulated by the mTORC1 pathway, through a known phosphorylation site in eEF2K (S396), and that it affects rates of localized protein synthesis at synapses depending on the presence or absence of this scaffolding protein.

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The efficiency of voluntary risk classification in insurance markets
Authors: Crocker Keith J. , Zhu Nan
Published: September 2020

It has been established that categorical discrimination based on observable characteristics such as gender, age, or ethnicity enhances efficiency. We consider a different form of risk classification when there exists a costless yet imperfectly informative test of risk type, with the test outcome unknown to the agents ex ante. We show that a voluntary risk classification in which agents are given the option to take the test always increases efficiency compared with no risk classification. Moreover, voluntary risk classification also Pareto dominates a regime of compulsory risk classification in which all agents are required to take the test.