bluuebunny/crossref_metadata_2025_split huggingface dataset:
Confession or justification: The effects of environmental disclosure on corporate green innovation in China
Authors: Xiang Xiaojian , Liu Chuanjiang , Yang Mian , Zhao Xiaomeng 
Published: August 2020

AbstractAs one type of voluntary environmental regulations, environmental disclosure plays an important role in promoting sustainable development of enterprises by enhancing their environmental awareness. Based on the social responsibility and annual reports published by heavily polluting listed companies in China between 2007 and 2016, this article investigates their environmental disclosure and assesses the impact on their green innovation activities as well as its influence mechanisms. Text analysis is used to measure the environmental disclosure by way of three dimensions including environmental investment and management, environmental supervision and agency certification, and environmental performance and governance. The results of the Poisson regression model for panel data show that environmental disclosure has significantly encouraged green innovations carried out by heavily polluting listed companies in China during the past decade and this result is consistent with a variety of robustness checks. Besides, the mediation effect test demonstrates that environmental disclosure stimulated green innovations of heavily polluting listed companies by expanding their financing channels, promoting their product sales, and raising media attention.
A low‐complexity pilot contamination elimination method for channel estimation in massive MIMO systems
Authors: Ebrahimi Reza , Zamiri‐Jafarian Hossein , Khademi Morteza 
Published: August 2020

SummaryPilot contamination is a major limitation in estimating the uplink channel state in massive MIMO systems using time division duplex communication method. This limitation has a huge impediment to harnessing the main advantages of massive MIMO systems such as spectral and energy efficiencies. In this article, a new low‐complexity subspace‐based method is proposed for eliminating pilot contamination and channel estimation, which exploits virtual channel modeling combined with a new problem formulation technique. On the contrary to most of the existing approaches in which the availability of correlation matrices of users and intercell data exchanges are needed, the proposed method eliminates the pilot contamination without need these confining assumptions. By employing the virtual beam searching technique and projection onto the component subspaces of virtual beams and pilot sequences, the proposed method estimates channel vectors of different cell users with very low computational complexity. Simulation results show that the proposed method achieves good performance with very low normalized mean square error and high achievable rates in the presence of severe pilot contamination and under different cell conditions.
Effects of time‐variant modal frequencies of high‐rise buildings on damping estimation
Authors: Zhou Kang , Li Qiu‐Sheng 
Published: August 2020

SummaryThis paper proposes a method to identify the time‐variant modal frequencies of high‐rise buildings and applies the method to the field measurements from a 68‐story high‐rise building during Super Typhoon Mangkhut (September 16, 2018). The analyzed results show that the fundamental natural frequencies of the monitored building first gradually decreased by about 9% and then returned to 94% of the original values over time. Moreover, the effects of time‐variant modal frequencies on damping estimation of high‐rise buildings are investigated by a comprehensive parametric study. The results indicate that the change rate of frequency has significant effects on the damping estimation by the conventional modal identification methods such as the random decrement technique and Bayesian spectral density approach. Accordingly, an error model for describing the relationship between the estimation error of damping ratio and main parameters of time‐variant modal frequencies is established. Then, an error model‐based correction method is proposed for the conventional damping identification methods to eliminate the estimation errors of damping ratios due to the time‐variant modal frequencies, which is proved to be effective through Monte Carlo simulation and is further applied to identify the time‐variant damping ratios of the monitored high‐rise building. This paper aims to further the understanding of structural dynamic properties of high‐rise buildings during typhoons and provide accurate estimation of structural modal parameters.
The potential of portable luminescence readers in geomorphological investigations: a review
Authors: Munyikwa Kennedy , Kinnaird Tim C. , Sanderson David C.W. 
Published: August 2020

AbstractThe development of functional portable optically stimulated luminescence (OSL) readers over the last decade has provided practitioners with the capability to acquire luminescence signals from geological materials relatively rapidly, which allows for expedient preliminary chronostratigraphic insight when working with complex depositional systems of late Quaternary age. Typically, when using the portable OSL reader, infrared (IR) or blue post‐IR OSL signals are acquired from bulk unprocessed materials, in contrast to regular luminescence dating, which is usually based on measurements on pure quartz or feldspar mineral separates, or on select silt‐sized polymineralic portions. To demonstrate the utility of portable OSL measurements, this paper outlines the basic features of portable OSL readers and their constraints. Subsequently, case studies in which the instrument has been used to elucidate cryptostratigraphic variations in sedimentary sequences for geomorphological applications are reviewed. The studies can generally be grouped into three main categories. The first includes studies where the variation of portable OSL reader luminescence signal intensities with depth are plotted to generate profiles that contextualize sediment stratigraphy. In the second group, portable OSL reader luminescence signal intensities are used to interpret sediment processes that shed light on depositional histories. In the last category, luminescence signals from the portable OSL reader are calibrated to approximate numerical burial ages of depositional units. The paper concludes with a discussion of possible future directions. © 2020 John Wiley & Sons, Ltd.
A novel multi‐image visually meaningful encryption algorithm based on compressive sensing and Schur decomposition
Authors: Ye Guodong , Pan Chen , Dong Youxia , Jiao Kaixin , Huang Xiaoling 
Published: August 2020

AbstractImage encryption algorithm is an important telecommunication technology for protecting personal security. In this article, we propose a novel multi‐image visual encryption algorithm based on compressive sensing (CS) and Schur decomposition. First, multiple images are sparsed by a discrete wavelet transform, and the compressed images are obtained by zigzag confusion and CS. Second, these compressed images are combined according to random sequences and scrambled again to obtain the secret image. Third, the carrier image is subjected to a two‐level lifting wavelet transform where the low‐frequency and high‐frequency subbands are selected to perform a discrete cosine transform (DCT). Fourth, Schur decomposition is employed on the secret image to calculate an upper triangular matrix and a unitary matrix (orthogonal matrix) to be embedded into the DCT coefficients of the previous low‐frequency and high‐frequency subbands, respectively. With an inverse transformation, the final visually meaningful encrypted image is achieved. Here, the initial position of the zigzag confusion is related to the plain image, which can effectively resist known‐plaintext and chosen‐plaintext attacks. The simulation results demonstrate that the proposed algorithm has high security and good imperceptibility.
Nexus between corporate social responsibility and firm’s performance: A panel data approach
Authors: Mughal Yasir Hayat , Jehangir Mahad , Khan Muzzamil , Saeed Mehran 
Published: August 2020

AbstractThe purpose of this study is to investigate the relationship between corporate social responsibility and firm performance. Secondary data from 28 firms registered at stock exchange were selected as population of the study. Data from time period of 8 years from 2009–2017 was taken from annual reports and statements of firms. For statistical analysis STATA‐12 was used. Levin‐Lin‐Chu test is used for data stationarity. Mean,SD, correlation analysis and pooled ordinary least square were used for testing hypotheses. Fixed effect model and random effect model, Hausman test were used. Corporate social responsibility scored highest mean followed by returns on equity, earnings per share and lowest mean was scored by returns on assets. Correlation analysis revealed the positive and significant relationship among all variables. Pooled ordinary least square results show that corporate social responsibility has significant impact upon returns on assets, returns on equity and earnings per share. But most dominant is earning per share from coefficient value. Previous studies which claimed that by identifying CSR activities in annual reports would result in low returns on assets, low returns on equity and less earnings per share. Thus, findings of this study explained that by showing CSR in annual reports could result in high returns on assets, equity and earnings per share. This study have implications for firms, firms can take competitive advantage by taking part in CSR activities, by doing so will retain talented employees, enhanced brand image, reputation in society and attract more investors for firms.
U.S. stock prices and macroeconomic fundamentals: Fresh evidence using the quantile ARDL approach
Authors: Shahzad Syed Jawad Hussain , Hurley Dene , Ferrer Román 
Published: August 2020

AbstractThis paper explores the long‐run relationship and the associated short‐run dynamics between the U.S. stock market and three major macroeconomic fundamentals, namely the U.S. industrial production index, the U.S. 10‐year Treasury bond yield and the West Texas Intermediate oil price, for the time period covering 1985–2015. The quantile autoregressive distributed lag (QARDL) model presented by Cho et al. (2015) Journal of Econometrics, 188, 281–300, which combines the autoregressive distributed lag model of Pesaran and Shin (1998), Cambridge University Press, and Pesaran et al. (2001) Journal of Applied Econometrics, 16, 289–326, and the quantile regression methodology of Koenker and Bassett (1978), Econometrica, 46, 33–50, is used. This approach analyses the links among the variables over a range of quantiles which represent different states of the equity market. The findings show a significant quantile‐varying cointegration relationship between U.S. equity prices and the three selected macroeconomic factors. The U.S. industrial production index is found to have the largest long‐run influence on the equity market. These findings highlight the importance of market players as well as policymakers to develop a greater understanding and awareness of how macro variables impact stock prices under different stock market conditions, particularly in relation to optimal asset allocation and risk management strategies, among others.
Backtesting expected shortfall for world stock indexETFswith extreme value theory andGram–Charliermixtures
Authors: Molina‐Muñoz Enrique , Mora‐Valencia Andrés , Perote Javier 
Published: August 2020

AbstractThis paper analyses risk quantification for three main stock market index exchange‐traded funds in world financial markets. We compare the relative performance of a set of parametric and semi‐nonparametric models in terms of both value‐at‐risk and expected shortfall backtesting techniques. To this end, we explore the result of the jointly elicitability of these two risk measures. We provide a new mixture of Gram–Charlier distributions that have been used in this framework for the first time and derive a close formula for directly computing expected shortfall. This model is compared to the Gaussian (benchmark model), Student'st, generalized Pareto (a case of the extreme value theory) and mixtures of Gram–Charlier distributions. The results show that peaks‐over‐threshold (extreme value theory) and flexible Gram–Charlier approximations are suitable to quantify market risk and mitigate concerns about possible financial instabilities generated by misuse of exchange‐traded funds trading.
The effects of institutional settings and risks on bank dividend policy in an emerging market: Evidence from Tobit model
Authors: Athari Seyed Alireza 
Published: August 2020

AbstractThis study investigates specifically the effects of institutional settings and risks on dividend payout policy for banks operate in an emerging market of Nigeria. The present study measures the risk by using financial, business, credit, and default risk at the bank‐level and financial, economic, and political risk at the country level. To achieve the objective of this study, panel data random‐effects Tobit estimation methodology is employed from the period 2007–2016. Findings reveal that the weak institutional settings lead Nigerian banks to pay out fewer dividends and set their payouts corresponding to the substitution agency model of dividends. Also, results show that Nigerian banks typically pay out more dividends in cases of growth opportunity as a substitute mechanism for mitigating agency problems and for establishing a good reputation. However, by strengthening the levels of investor protection, Nigerian bank managers prefer a low payout policy and are less probable to use dividend policies as a substitute mechanism. Moreover, except for the positive effect of default risk, findings show that the risks at the bank‐level, in particular, business risk, and at the country level, particularly financial and economic risks, have a significant negative effect on dividend payouts. Results are robust to alternative estimation procedures and also document that global risk has a statistically significant negative impact on Nigerian banks' dividend payouts policy.
Spillovers and jumps in global markets: A comparative analysis
Authors: Moura Rodolfo C. , Laurini Márcio P. 
Published: August 2020

AbstractWe analyse the relation between volatility spillovers and jumps in financial markets. For this, we compared the volatility spillover index proposed by Diebold and Yilmaz, The Economic Journal, 2009, 119, 158–171 with a global volatility component, estimated through a multivariate stochastic volatility model with jumps in the mean and in the conditional volatility. This model allows a direct dating of events that alter the global volatility structure, based on a permanent/transitory decomposition in the structure of returns and volatilities and the estimation of market risk measures. We conclude that the multivariate stochastic volatility model complements the information revealed by the spillover index and can be a useful tool in measuring and managing risk in global financial markets.
3D bioprinted glioma microenvironment for glioma vascularization
Authors: Wang Xuanzhi , Li Xinda , Ding Jinju , Long Xiaoyan , Zhang Haitao , Zhang Xinzhi , Jiang Xiaochun , Xu Tao 
Published: August 2020

AbstractGlioblastoma is the most frequently diagnosed primary malignant brain tumor with unfavourable prognosis and high mortality. One of its key features is the extensive abnormal vascular network. Up to now, the mechanism of angiogenesis and the origin of tumor vascularization remain controversial. It is essential to establish an ideal preclinical tumor model to elucidate the mechanism of tumor vascularization, and the role of tumor cells in this process. In this study, both U118 cell and GSC23 cell exhibited good printability and cell proliferation. Compared with 3D‐U118, 3D‐GSC23 had a greater ability to form cell spheroids, to secrete vascular endothelial growth factor (VEGFA), and to form tubule‐like structures in vitro. More importantly, 3D‐glioma stem cells (GSC)23 cells had a greater power to transdifferentiate into functional endothelial cells, and blood vessels composed of tumor cells with an abnormal endothelial phenotype was observed in vivo. In summary, 3D bioprinted hydrogel scaffold provided a suitable tumor microenvironment (TME) for glioma cells and GSCs. This bioprinted model supported a novel TME for the research of glioma cells, especially GSCs in glioma vascularization and therapeutic targeting of tumor angiogenesis.
The role ofBacillus acidophilusin osteoporosis and its roles in proliferation and differentiation
Authors: Chen Chen , Dong Baokang , Wang Yuming , Zhang Qiang , Wang Bangmao , Feng Shuzhi , Zhu Yu 
Published: August 2020

AbstractBackgroundOsteoporosis is one of the most closely related diseases associated with the elderly. In recent years, the studies found that gut microbiota can cause osteoporosis. We evaluated the role of Bacillus acidophilus in osteoporosis and its roles in proliferation and differentiation.MethodsWe selected 5 healthy people and 10 osteoporosis patients and analyzed their level of 25‐hydroxyvitamin D and procollagen type I N‐terminal peptide (PINP), the characteristic of gut microbiota. The effect oflactobacillus acidophilus and Lactobacillus rhamnosussupernatant and butanoic acids on proliferation, differentiation, and maturity of osteoblasts MC3T3‐E1 and osteoclasts RAW 264.7 cells and the activity of alkaline phosphatase, concentration of osteocalcin, and the expression of RUNX2, RANK, NFATc1, cathepsin K, DC‐STAMP, OSCAR, WNT2, and CTNNB1 were measured in the above cell lines.ResultsThe diversity of gut microbiota in osteoporosis patients is decreased and imbalanced with lower abundance of lactobacillus and butyric acid bacteria; meanwhile, 25‐hydroxyvitamin D and PINP of osteoporosis patient were significantly lower than the normal group. The proliferation, differentiation, and maturity of MC3T3‐E1 cells were stimulated; the activity of alkaline phosphatase, concentration of osteocalcin, and the expression of RUNX2, NFATc1, cathepsin K, DC‐STAMP, OSCAR, WNT2, and CTNNB1 were improved by supernatant oflactobacillus acidophilus,Lactobacillus rhamnosusand butanoic acids; however, the proliferation, differentiation, maturity, and the expression of RANK, NFATc1, cathepsin K, DC‐STAMP, OSCAR, WNT2, and CTNNB1 in RAW 264.7 cells were suppressed.ConclusionsThelactobacillus acidophilusandLactobacillus rhamnosussupernatant could stimulate the proliferation, differentiation, and maturation of osteoblasts; the production of butyric acid may be the potential mechanism.
Long noncoding RNA HNF1A‐AS1 regulates proliferation and apoptosis of glioma through activation of the JNK signaling pathway via miR‐363‐3p/MAP2K4
Authors: Bi Yongyan , Mao Yuhang , Su Zuopeng , Du Jiarui , Ye Liping , Xu Fulin 
Published: August 2020

AbstractLong noncoding RNAs (lncRNAs) have been proven to exert important functions in the various biological processes of human cancers. It has been reported that lncRNA HNF1 homeobox A antisense RNA 1 (HNF1A‐AS1) was abnormally expressed and played a role in the initiation and development of various human cancers. In this study, we confirmed that the expression level of HNF1A‐AS1 was increased in glioma tissues and cells. Knockdown of HNF1A‐AS1 inhibited cell proliferation and promoted cell apoptosis in glioma. Then, we disclosed the downregulation of miR‐363‐3p in glioma tissues and cell lines. The interaction between HNF1A‐AS1 and miR‐363‐3p was identified in glioma cells. Furthermore, an inverse correlation between HNF1A‐AS1 and miR‐363‐3p was observed in glioma tissues. Afterwards, we recognized that MAP2K4 was a direct target of miR‐363‐3p. The expression of MAP2K4 was negatively correlated with miR‐363‐3p while positively related to HNF1A‐AS1 in glioma tissues. We also found the regulatory effect of HNF1A‐AS1 on the MAP2K4‐dependent JNK signaling pathway. All findings indicated that HNF1A‐AS1 induces the upregulation of MAP2K4 to activate the JNK signaling pathway to promote glioma cell growth by acting as a miR‐363‐3p sponge.
The role of the 5′ HoxA genes in the development of the hindgut, vent, and a novel sphincter in a derived teleost (bluebanded goby, Lythrypnus dalli)
Authors: Crow Karen D. , Sadakian Ara , Kaslly Noelle A. 
Published: August 2020

AbstractUnique expression patterns of the 5′ HoxA genes are associated with the evolution and development of novel features including claspers in cartilaginous fishes, modified pectoral fins in batoids, and the yolk sac extension in Cypriniformes. Here, we demonstrate a role for HoxA11a and HoxA13a in demarcating the hindgut in fishes of the family Gobiidae, including a novel sphincter called the intestinal rectal sphincter (IRS). Disruption of 5′ HoxA expression, via manipulation of retinoic acid signaling, results in failure of the IRS and/or vent to develop. Furthermore, exposure to HoxA disruptors alters 5′ HoxA expression, in association with developmental phenotypes, demonstrating a functional link between 5′ HoxA expression and development of a novel feature in the bluebanded goby, Lythrypnus dalli.
Evolution of the acoustic startle response of Mexican cavefish
Authors: Paz Alexandra , McDole Brittnee , Kowalko Johanna E. , Duboue Erik R. , Keene Alex C. 
Published: August 2020

AbstractThe ability to detect threatening stimuli and initiate an escape response is essential for survival and under stringent evolutionary pressure. In diverse fish species, acoustic stimuli activate Mauthner neurons, which initiate a C‐start escape response. This reflexive behavior is highly conserved across aquatic species and provides a model for investigating the neural mechanism underlying the evolution of escape behavior. Here, we characterize evolved differences in the C‐start response between populations of the Mexican cavefish, Astyanax mexicanus. Cave populations of A. mexicanus inhabit an environment devoid of light and macroscopic predators, resulting in evolved differences in various morphological and behavioral traits. We find that the C‐start is present in river‐dwelling surface fish and multiple populations of cavefish, but that response kinematics and probability differ between populations. The Pachón population of cavefish exhibits an increased response probability, a slower response latency and speed, and reduction of the maximum bend angle, revealing evolved differences between surface and cave populations. Analysis of the responses of two other independently evolved populations of cavefish, revealed the repeated evolution of reduced angular speed. Investigation of surface‐cave hybrids reveals a correlation between angular speed and peak angle, suggesting these two kinematic characteristics are related at the genetic or functional levels. Together, these findings provide support for the use of A. mexicanus as a model to investigate the evolution of escape behavior.