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SYNOPSIS We examine (1) the association between global-level and joint global-, national-, and city-level auditor industry specialization and audit clients’ cost of equity capital and (2) how the national investor protection environment impacts the preceding association. Our results indicate that cost of equity capital is negatively associated with global-level and joint global-, national-, and city-level auditor industry specialization. This relation is incrementally more negative when the auditor is a joint global-, national-, and city-level industry specialist than when the auditor is not a global-level industry specialist. We also find the negative relation between cost of equity capital and joint global-, national-, and city-level auditor industry specialization holds only in countries with strong investor protection. We further show investors perceive potential accentuation of accruals quality and ownership concentration on cost of equity is mitigated by joint global-, national-, and city-level specialist auditors. JEL Classifications: M42; G32; K49.

CRISPR-based biosensing technology has been emerging as a revolutionary diagnostics for many diseases-related biomarkers. In particular, RspCas13d, a newly identified RNA-guided Cas13d ribonuclease derived from Ruminococcus sp., has shown great promise for accurate and sensitive detection of RNA due to its RNA sequence-specific recognition and robust collateral trans-cleavage activity. However, its diagnostic utility is limited to detect nucleic-acid-related biomarkers. To address this limitation, we herein present a proof-of-concept demonstration of a target-responsive CRISPR-Cas13d sensing system for protein biomarkers. Such a system is rationally designed by integrating a Dual-Aptamer-based Transcription Amplification Strategy with CRISPR-Cas13d (DATAS-Cas13d), in which the protein binding initiates the in vitro RNA transcription followed by the activation of RspCas13d. Using a short fluorescent ssRNA as the signal reporter and cardiac troponin I (cTnI) as the model analyte, the DATAS-Cas13d system showed a wide linear range, low detection limit and high specificity for the detection of cTnI in buffer and human serum. Thanks to the facile integration of various bioreceptors into the DATAS-Cas13d system, the method could be adapted to detecting a broad range of clinically relevant protein biomarkers, and thus broaden the medical applications of Cas13d-based diagnostics.

Chitosan (CS), the only alkaline polysaccharose available in nature, has always been a promising candidate for drug delivery owing to its excellent biodegradability and biocompatibility. However, inherent solubility and polycationic properties of CS largely hinder electrospinning, which is an efficient method of fabricating nanofibers for drug carriers. To solve this problem and extend the applications of CS, polyamide/chitosan/tetraethyl orthosilicate (PA/CS/TEOS) composite nanofibers were successfully prepared as drug carriers in this study via electrospinning. The PA/CS/TEOS ratios significantly influenced the nanofiber morphology. As the content of each was increased, the beads among the membranes increased initially and then decreased, determined by scanning electron microscopy (SEM). The morphology of the optimum membranes with the ratio of 1:0.13:0.67 was smoother with less beads and uniform fiber diameter. Finally, the membranes with optimum ratios were used as carriers of ofloxacin in the study of drug release performance to identify their future feasibility, which revealed an initial fast release followed by a relatively stable release.

Owing to the significance and requirement of renewable energy resources, in this study, ellipsoidal porous carbons with yolk-shell structures assembled using MnO and Ganoderma lucidum spores are fabricated for application prospects in energy storage systems; they exhibit excellent ion transfer capability. However, the surface of carbon nanomaterials is naturally hydrophobic, resulting in a lower energy density. Herein, heteroatom doping and O2/Ar plasma surface treatment are utilized to obtain high specific capacitance and fast charging. Surface functionalization increases the surface roughness and oxygen-containing functional groups of the material. The specific capacitance of the best sample MnO/GSC-O–NS–10 was 568.9 F g−1 when the current density was 0.5 A g−1. The performance test was carried out for 10000 cycles at a current density of 10 A g−1 and the capacitance retention rate was 75.11%. The assembled two-electrode capacitor exhibited a specific capacitance of 240.4 F g−1 and an energy density of 33.4 Wh kg−1 at a power density of 407 W kg −1. These findings provide sufficient theoretical guidance for the development of high-performance supercapacitors.

Silicon (Si) is widely considered to be the most attractive candidate anode material for use in next-generation high-energy-density lithium (Li)-ion batteries (LIBs) because it has a high theoretical gravimetric Li storage capacity, relatively low lithiation voltage, and abundant resources. Consequently, massive efforts have been exerted to improve its electrochemical performance. While some progress in this field has been achieved, a number of severe challenges, such as the element’s large volume change during cycling, low intrinsic electronic conductivity, and poor rate capacity, have yet to be solved. Methods to solve these problems have been attempted via the development of nanosized Si materials. Unfortunately, reviews summarizing the work on Si-based alloys are scarce. Herein, the recent progress related to Si-based alloy anode materials is reviewed. The problems associated with Si anodes and the corresponding strategies used to address these problems are first described. Then, the available Si-based alloys are divided into Si/Li-active and inactive systems, and the characteristics of these systems are discussed. Other special systems are also introduced. Finally, perspectives and future outlooks are provided to enable the wider application of Si-alloy anodes to commercial LIBs.

This article presents a method to design new diplexer-integrated single-pole double-throw (SPDT) switches for composite time division duplexing (TDD) and frequency division duplexing (FDD) requirements. The common fractal stub-loaded resonator (F-SLR) is employed to provide four magnetic coupling paths to introduce the mixed electric and magnetic coupling (MEMC) for every channel. Together with the cross-couplings, the ON-state channel with high selectivity bandpass response can be achieved. As examples, a third-order diplexer-integrated SPDT switch and a fourth-order diplexer-integrated SPDT switch operating at 0.9/1.8 GHz are designed and fabricated. These two diplexer-integrated SPDT switches have three major operating modes, i.e., the 0.9-GHz bandpass filter (BPF)-integrated SPDT switch operating mode, the 1.8-GHz BPF-integrated SPDT switch operating mode, and the 0.9-/1.8-GHz diplexer-integrated SPDT switch operating mode. In the design, the loaded positions of p-i-n diodes on the uniform impedance resonators of 0.9-GHz channel are optimized to improve the OFF-state rejection bandwidth. Measured results also show that these two diplexer-integrated SPDT switches have low ON-state passband insertion loss, high port-to-port isolation, and compact circuit size.

The effects of corporate governance (CG) on earnings management (EM) have been debated for many years. Thus, this paper explores this issue in a novel way that utilizes a quantile regression to revisit the association between CG mechanisms and EM. We find that a non‐uniform relation between CG mechanisms and EM for non‐financial U.S. firms does exist from 2007 to 2015. Specifically, the empirical evidence documents that CG mechanisms can effectively constrain earning manipulation among firms with higher discretionary accruals (High EM). However, this effect becomes insignificant for firms with medium and low levels of discretionary accruals (Low EM). The quantile‐varying results provide further support for the theoretical viewpoint that the CG mechanism can serve as an effective tool for supervising management in the financial accounting process but only in the case of firms with aggressive EM behaviour.

This study examines the association between the new drug approvals released by the US Food and Drug Administration (FDA) and subsequent market stock price reactions for listed pharmaceutical and bi...

An electrochemical aptasensor for detecting trace aflatoxin B1 (AFB1) is designed and fabricated consisting of aptamers and gold nanoparticles on conductive boron-doped diamond (BDD) electrode. By examining the relative impedance shift from electrochemical impedance spectroscopy as a function of AFB1 concentration, the low detection limit (wide linear relationship range) of the aptasensor is realized to be 5.5 × 10−14 mol L−1 (1.0 × 10−13‒1.0 × 10−8 mol L−1). The variation in impedance property of the aptasensor is determined by the specific adsorption of AFB1 molecules to the aptamer at a certain concentration covering the electrode. By means of multiple characteristic processes, it is demonstrated that the constructed aptasensor is favorable for testing the trace AFB1 with high specificity, sensitivity, stability, repeatability, and reusability, which lead to a possibility to achieve high performance biosensor for practical application to quantitatively detract trace AFB1 in environments.

This article presents a type of bandpass filter (BPF)-integrated single-pole double-throw (SPDT) switch using the frequency selective star-junction matching circuit and the switched magnetic coupling (SMC) technique, i.e., the lowpass phase shifter (LP-PS) and the quasi-elliptic lowpass filter (QE-LPF) with specified phase shift. Firstly, a high selectivity third-order BPF-integrated single-pole single-throw (SPST) switch with cross coupling and mixed electric and magnetic coupling (MEMC) is designed by the classical coupled-resonator filter design theory. A 34-dB OFF-state suppression (OSS) is achieved due to the detuned resonators, and the OSS can be further increased to 60 dB by the introduced SMC. Then, the BPF-integrated SPDT switches are designed by using proposed frequency selective star-junction matching circuit to cascade the above designed BPF-integrated SPST switch with or without SMC. The proposed frequency selective star-junction matching circuit is used to not only provide the required phase shift for meeting the impedance matching condition, but also have lowpass frequency response for expanding the upper stopband of ON-state channel, the rejection bandwidth of OFF-state channel, and the port-to-port isolation bandwidth. As examples, four BPF-integrated SPDT switches are designed and fabricated to validate the proposed design approaches, which show the improved electrical performance.

This article presents a method to design a single-band (SB)/dual-band (DB) bandpass filter (BPF)-integrated single-pole double-throw (SPDT) switch by using one/two distributed coupling identical tri-mode resonator (TMR) pairs loaded with opposite polarity p-i-n diodes. Moreover, the proposed method is also directly suitable for designing the multiple-band (MB) BPF-integrated SPDT switch by simply increasing the used numbers of identical TMR pairs. As an example, a SB-BPF-integrated SPDT switch with the central frequency (CF) of 1 GHz and the ripple bandwidth (RBW) of 65 MHz is first designed by using one identical switchable TMR pair, so as to validate our design approach. Due to the inherent property of TMR and the introduced source–load coupling, high ON-state passband selectivity is achieved. Then, two switched 50- $\Omega $ matching circuits are connected to two noncommon feeding lines, and an SB-BPF-integrated SPDT switch with absorptive OFF-state property is also realized. Finally, a DB-BPF-integrated SPDT switch with CFs of 0.9 GHz/1.8 GHz and RBWs of 50 MHz/105 MHz is designed by simply employing two identical TMR pairs. When the operating states of two identical switchable TMR pairs are specifically chosen, the proposed DB-BPF-integrated SPDT switch exhibits multiple functions, i.e., the 900/1800 SB-BPF-integrated SPDT switches with absorptive OFF-state property, the 900/1800 DB-BPF-integrated SPDT switch with absorptive OFF-state property, and the 900/1800 diplexer-integrated SPDT switch. The measured results also show that these switches exhibit low ON-state passband losses, deep out-of-band rejections (OBRs) of ON-state passbands, high OFF-state suppressions (OSSs), high port-to-port isolations (PPIs), and compact circuit sizes.

Hierarchical porous carbons (HPCs) have been successfully prepared by a facile carbonization and subsequent CO2 activation process using corncob as a natural carbon precursor and Mg(C2H3O2)2 as a MgO nano-template precursor. The prepared corncob-based hierarchical porous carbons (C-HPCs) with desirable micropores and mesopores feature the excellent absorbency of gas (i.e., CO2 and CH4) and solution (i.e., methylene blue (MB)). Increasing the ratio of Mg(C2H3O2)2/corncob enlarged the specific surface area up to 1004 m2/g, micropore and mesopore volumes, CO2, CH4, and MB adsorption capacities (112, 31 and 230 mg/g after 325 min, respectively). The results indicated that the pore structures of C-HPCs can be easily and suitably controlled by the amount of the template precursor and CO2 activation effecting concurrently, which leads to fascinating adsorption capacity for CO2, CH4, and MB.

We explore whether firms’ corporate social responsibility (CSR) activities provide added value to capital market participants through seasoned equity offerings (SEOs). SEOs represent cleaner exogenous activity alleviating the reverse causality issue plaguing many prior studies examining the relation between firm performance and CSR. Using a large sample of U.S. SEOs, we find high-CSR issuers experience fewer negative market reactions to SEO announcements. We also show ethical issuers have incentive to provide extensive and informative disclosures, which mitigate the degree of information asymmetry, thereby decreasing SEO underpricing. Among CSR categories, we find issuers engaging in community and environmental CSR activities and improving the rights of women and minorities are more effective at reducing SEO negative announcement returns and underpricing. Our findings remain robust after controlling for possible self-selection bias and endogeneity problems. Overall, our findings support the stakeholder value maximization view of stakeholder theory and ethical theory.

This study examines the impact of corporate social responsibility (CSR) in the tourism industry using seasoned equity offerings (SEOs) from 1992 to 2015. We show that tourism SEO issuers engaging in CSR activities experience less negative market reactions to SEO announcements. The findings also reveal that the negative reactions around SEO announcements are significantly lessened for tourism firms with better CSR performance in the context of high information asymmetry, because such activities serve as an ethical commitment to outside investors, and thus align the interests between SEO issuers and outside investors, which eventually mitigates negative market reactions to SEO announcements. Overall, these results indicate that tourism issuers with better CSR performance are able to reduce the agency costs and adverse selection problem for uninformed investors in the process of issuing SEOs.

This article answers the question of whether the adoption of International Financial Reporting Standards (IFRS) reduces the cost of equity capital, with a focus on the tourism industry. We employ a set of global tourism companies and find that mandatory IFRS adoption has a significantly negative relation with the cost of equity capital. However, we find that this relation is varied with different business cultures and geographic areas. Moreover, from interactive analyses of country institutions for the relation between mandatory IFRS adoption and tourism firm’s cost of equity, we show that adopting IFRS complements the deficiencies of various country institutions, such as investor protection, the strength of legal enforcement, and corporate governance.

The contact angle and surface energy values of diamond are systemically investigated in terms of surface treatments (hydrogen- and oxygen-terminations), structure feature (single crystal diamonds and polycrystalline diamond films), crystal orientation ((100), (111) and mixed (100)/(111) orientations), different fluids (probes of polar deionized water and nonpolar di-iodomethane). It is found that the hydrophobic/hydrophilic characteristic and surface energy values of diamond are mainly determined by the surface hydrogen/oxygen termination, and less related to the structural features and crystal orientation. Based on the contact angle values with polar water and nonpolar di-iodomethane, the surface energies of diamond are estimated to be about 43 mJ/m2 for hydrogen-termination and about 60 mJ/m2 for oxygen-termination. Furthermore, the varying surface roughness of diamond and fluids with different polarities examined determine the variation of contact angles as well as the surface energy values. These results would be helpful for a more detailed understanding of the surface properties of diamond films for further applications in a broad number of fields, such as optical and microwave windows, biosensors, and optoelectronic devices, etc.

This paper examines (1) whether auditor type affects initial public offering (IPO) pricing; (2) whether the effect of IPO pricing is different for clients with different ownership structures. We find that (1) firms being audited by Big 4 accounting firms receive IPO premium while others being audited by local accounting firms do not; (2) Big 4 auditors receive higher audit fees than China’s Top 10 or small local auditors. This paper extends the prior research (e.g., Kumar, P and N Langberg (2009). Corporate fraud and investment distortions in efficient capital markets. The RAND Journal of Economics, 40, 144–172) that reduces agency conflicts between shareholders and manager (by means of better audit quality) and also reconciles corporate misreporting and investment distortions.

This paper investigates how corporate social responsibility (CSR) influences the cost of equity capital from a global perspective. With a full sample of 10,803 firm-year observations from 25 countries, the study finds that, in general, firms with better CSR scores are significantly associated with a reduced cost of equity capital in North America and Europe. In contrast, the results do not continue to hold in Asian countries. Our study provides implications for global regulators and policymakers when setting social reporting standards, suggesting that institutional and/or cultural factors affect top management's social reporting behavior and regional investors' impressions of CSR value. In particular, the Asian regulators should effectively promote public understanding and awareness of CSR information. Additionally, our findings may be informative to international managers and investors when considering CSR as an indicator in their internal governance designation and decision-making. Firms should carefully evaluate the risk of CSR investing and its effect on equity financing in different regions.

This study evaluates a time changed Levy model for European call options under a fuzzy environment. The proposed model is characterized by high frequency jumps, stochastic volatility, and stochastic volatility with the jumps, existing in the returns process of financial assets. Moreover, to consider imperfect and unpredictable accounting information, this study uses fuzzy logic to account for the impreciseness of the accounting information, which can not be described in extant models, and provides reasonable reference instruments for future research on option pricing under a jump diffusion model with imprecise market information. Our empirical results also show that the fuzzy time changed Levy model has better fitting performance when compared with the time changed Levy and the Black and Scholes model when using S&P 500 index option data.

This paper examines whether the performance of corporate social responsibility (CSR) affects the cost of equity capital for the tourism industry, and whether there are any regional and cultural differences in this respect. Using data from a global sample of tourism-related firms, the authors find that, on average, CSR performance is associated with a lower cost of equity for firms in Western countries, but not for firms in Asian countries. The results suggest that there are different concerns with regard to CSR investment for tourism-related firms in different regions, due to the variations in investors' perceptions, culture, institutional environment and managerial beliefs.

An electronic differential control system (EDS) has been designed based on a mini electric vehicle (EV) with dual in-wheel-motor rear drive. In view of imperfection of current strategy with speed and moment as control variables, a new control strategy for EDS in a two in-wheel-motor drive EV is proposed with the moment of driving wheel torque as control variable and the slip rate equilibrium of two driving wheels as control objective, considering the effects of axle load transfer. The differential control experiments are conducted with steering mode and straight acceleration mode based on the vehicle prototype. The results show that the control strategy is reasonable, and the controller can effectively realize EV electronic differential by coordinating the moment of two driving wheels.

An experiment was conducted on densification processing of sorghum straw stalks with self-made steel molds on a hydraulic universal test platform. The influences of different densification conditions on physical quality of briquette fuel are investigated, including pressures, temperatures, moisture contents and straw preheating method. Moreover, the relationship between molding temperature and inner stress decreasing rate of straw briquette at holding pressure stage is also analyzed. The result shows that the suitable value of moisture content, temperature and molding pressure for straw compression process is 20%, 90°C and at least 50MPa, respectively. The phenomenon of uneven temperature distribution in straw briquette keeps in existence even in the case of microwave preheating. However, in contrast with the very low central temperature in straw briquette when preheating by electric heater wire, the phenomenon of local overheating caused by microwave preheating may be helpful to straw molding process.

Magnesium aluminate spinel specimens with various Al2O3 content were prepared. Sintering performance and microstructure of different kinds of MgAl2O4 spinel were studied. It is found that the sintering of materials becomes more difficult with the increase in their Al2O3 contents. Corundum begins to precipitate from the magnesium aluminate spinel with 85wt% Al2O3 at 1400. However, with further increase in the sintering temperature, the corundum dissolves into magnesium aluminate spinel (above 1600). The precipitation and solid solution of corundum hinder the sintering of materials. In alumina-rich spinel, if the content of Al2O3 in alumina-rich spinel materials is more and the content of CA6 is also more. At the same time CA6 crystal is bigger in the alumina-rich spinel.

On the basis that most instruments traded on options markets are American-style ones, this paper develops the analytical upper and lower bounds of American cross-currency and quanto options under the stochastic skew model proposed by Carr and Wu (2007) when domestic risk free rates are higher or lower than the foreign risk free rates. The analytical bounds derived here are not only very tight and accurate for American option pricing, but also offer a quasi-closed form solution which is able to enhance evaluation and hedging efficiency in real world markets. We also acquire the analytical solutions for European cross-currency and quanto options given by applying two separate mean-reverting square-root processes to two separate time-changed Levy processes, consistent with the realistic phenomena of currency returns.