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This study investigates the impact of media sentiment on firms' investment efficiency in the Chinese market during 2007–2017. We find that increased media sentiment can lead to overinvestment and thus distort investment efficiency, but it has no significant effect on underinvestment. Further, mediation analysis shows that financing constraints mediates the media sentiment effects on overinvestment. To mitigate potential endogenous problems, we employ instrumental variable approach and propensity score matching method. The main findings hold after a battery of robustness tests. Further tests show that corporate governance factors can ameliorate the adverse effect of news sentiment on corporate investment efficiency. [ABSTRACT FROM AUTHOR]

In this study, we examine the effects of lead independent directors (LIDs) on firms' earnings management. On the basis of US firms from 2000 to 2018, those with LIDs managed earnings less, as reflected by the absolute value of discretionary accruals. Specifically, we find the effect is likely to be more prominent among firms with less disclosure transparency, weaker corporate governance and higher risk. In addition, we find that firms with LIDs tend to increase R&D and capital expenditures, reduce leverages and enhance firm values. Overall, the findings indicate the monitoring of LIDs can effectively reduce firms' earnings management and enhance firm values. [ABSTRACT FROM AUTHOR]

Herein, we reported an intermolecular asymmetric hydrative aldol reaction through vinyl‐gold intermediate under ambient conditions. This tandem alkyne hydration and sequential nucleophilic addition afforded a "base‐free" approach to β‐hydroxy amides with high efficiency (up to 95 % yields, >50 examples). Vinyl gold intermediate was applied as reactive nucleophile and Fe(acac)3 was used as the critical co‐catalyst to prevent undesired protodeauration, allowing this transformation to proceed under mild conditions with good functional group tolerance and excellent stereoselectivity (>20 : 1 d.r. and up to 99 % ee). [ABSTRACT FROM AUTHOR]

Thickness‐tunable triple‐layer polyaniline (PANI)/clay nanocomposites were synthesized via in situ intercalative polymerization of PANI within the clay layers. The PANI/clay nanocomposites were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and thermogravimetric analysis. In this study, the thickness of the PANI/clay nanocomposites was easily controlled by adjusting the proportions of PANI and pristine clay. Based on oxygen transmission rate measurements, the oxygen barrier properties of pristine clay can be enhanced by the growth of PANI. Notably, the oxygen barrier property of epoxy loaded PANI/clay nanocomposites was linearly dependent on the PANI growth thickness. After 30 days immersion electrochemical impedance spectroscopy test under saline conditions, the resistance (Rc) of the pure epoxy coating (2.47 × 106 Ω) increased to 5.76 × 1010 Ω when 1 wt.% PANI was added to the epoxy coating. However, when 1 wt.% PANI/clay was added into the epoxy coating, the Rc of the composite coating increased further to 7.66 × 1011 Ω. Notably, the ratio of PANI to PANI/clay was only 36.5 wt.%, indicating synergistic anticorrosion properties can be obtained by the intercalation of PANI/clay additives. Therefore, PANI/clay nanocomposites have a high potential as anticorrosion additives for industrial epoxy resin coatings. [ABSTRACT FROM AUTHOR]

This study aims to investigate the day‐of‐the‐week effect of cross‐market leveraged exchange‐traded funds (LETFs) in the Taiwanese stock market. We find that Wednesday's overnight returns are significantly positive for bull 2X LETFs tracking major stock indices of the Chinese market, whereas no such an effect is found for ETFs tracking local or other international stock markets. The "T + 1" trading rule and a lagged Monday effect potentially explain this anomaly. Finally, simulation analysis of various simple trading rules further shows that there exist exploitable profit opportunities in cross‐market bull 2X LETF markets. [ABSTRACT FROM AUTHOR]

Chronic venous insufficiency is a chronic disease of the venous system with a prevalence of 25% to 40% in females and 10% to 20% in males. Venous leg ulcers (VLUs) result from venous insufficiency. VLUs have a prevalence of 0.18% to 1% with a 1‐year recurrence of 25% to 50%, bearing significant socioeconomic burden. It is therefore important for regular assessment and monitoring of VLUs to prevent worsening. Our study aims to assess the intra‐ and inter‐rater reliability of a machine learning‐based handheld 3‐dimensional infrared wound imaging device (WoundAide [WA] imaging system, Konica Minolta Inc, Tokyo, Japan) compared with traditional measurements by trained wound nurse. This is a prospective cross‐sectional study on 52 patients with VLUs from September 2019 to January 2021 using three WA imaging systems. Baseline patient profile and clinical demographics were collected. Basic wound parameters (length, width and area) were collected for both traditional measurements and measurements taken by the WA imaging systems. Intra‐ and inter‐rater reliability was analysed using intra‐class correlation statistics. A total of 222 wound images from 52 patients were assessed. There is excellent intra‐rater reliability of the WA imaging system on three different image captures of the same wound (intra‐rater reliability ranging 0.978‐0.992). In addition, there is excellent inter‐rater reliability between the three WA imaging systems for length (0.987), width (0.990) and area (0.995). Good inter‐rater reliability for length and width (range 0.875‐0.900) and excellent inter‐rater reliability (range 0.932‐0.950) were obtained between wound nurse measurement and each of the WA imaging system. In conclusion, high intra‐ and inter‐rater reliability was obtained for the WA imaging systems. We also obtained high inter‐rater reliability of WA measurements against traditional wound measurement. The WA imaging system is a useful clinical adjunct in the monitoring of VLU wound documentation. [ABSTRACT FROM AUTHOR]

There is a lifetime risk of 15% to 25% of development of diabetic foot ulcers (DFUs) in patients with diabetes mellitus. DFUs need to be followed up on and assessed for development of complications and/or resolution, which was traditionally performed using manual measurement. Our study aims to compare the intra‐ and inter‐rater reliability of an artificial intelligence‐enabled wound imaging mobile application (CARES4WOUNDS [C4W] system, Tetsuyu, Singapore) with traditional measurement. This is a prospective cross‐sectional study on 28 patients with DFUs from June 2020 to January 2021. The main wound parameters assessed were length and width. For traditional manual measurement, area was calculated by overlaying traced wound on graphical paper. Intra‐ and inter‐rater reliability was analysed using intra‐class correlation statistics. A value of <0.5, 0.5–0.75, 0.75–0.9, and >0.9 indicates poor, moderate, good, and excellent reliability, respectively. Seventy‐five wound episodes from 28 patients were collected and a total of 547 wound images were analysed in this study. The median wound area during the first clinic consultation and all wound episodes was 3.75 cm2 (interquartile range [IQR] 1.40–16.50) and 3.10 cm2 (IQR 0.60–14.84), respectively. There is excellent intra‐rater reliability of C4W on three different image captures of the same wound (intra‐rater reliability ranging 0.933–0.994). There is also excellent inter‐rater reliability between three C4W devices for length (0.947), width (0.923), and area (0.965). Good inter‐rater reliability for length, width, and area (range 0.825–0.934) was obtained between wound nurse measurement and each of the C4W devices. In conclusion, we obtained good inter‐rater and intra‐rater reliability of C4W measurements against traditional wound measurement. The C4W is a useful adjunct in monitoring DFU wound progress. [ABSTRACT FROM AUTHOR]

The rational design and construction of cost‐effective nickel‐based phosphide or sulfide (photo)electrocatalysts for hydrogen production from water splitting has sparked a huge investigation surge in recent years. Whereas, nickel phosphides (NixPy) possess more than ten stoichiometric compositions with different crystalline. Constructing NixPy with well crystalline and revealing their intrinsic catalytic mechanism at atomic/molecular levels remains a great challenge. Herein, an easy‐to‐follow phase‐controllable phosphating strategy is first proposed to prepare well crystalline NixPy (Ni3P and Ni12P5) modified CdS@Ni3S2 heterojunction electrocatalysts. It is found that Ni3P modified CdS@Ni3S2 (CdS@Ni3S2/Ni3P) exhibits remarkable stability and bifunctional electrocatalytic activities in both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Density functional theory results suggest that P–Ni sites and P sites in CdS@Ni3S2/Ni3P, respectively, serve as OER and HER active sites during electrocatalytic water splitting processes. Moreover, benefiting from the advantageous photocatalyst@electrocatalyst core@shell structure, CdS@Ni3S2/Ni3P delivers an advantaged photoassisted electrocatalytic water splitting property. The champion electrical to hydrogen and solar to hydrogen energy conversion efficiencies of CdS@Ni3S2/Ni3P, respectively, reach 93.35% and 4.65%. This work will provide a general guidance for synergistically using solar energy and electric energy for large‐scale H2 production from water splitting. [ABSTRACT FROM AUTHOR]

This study proposes a new measure of systemic risk named CSRISK, which identifies a financial institution's capital shortfall under the worst scenario conditional on a substantial market decline. The CSRISK index requires only public financial data, including accounting and market trading information, which is time and cost effective. The empirical sample consists of 238 US banks over the time period 2003–2013. Overall, we find that it is increasing from 2004 to 2009 and then starts to slightly decrease. This systemic risk measure has the potential to be widely applied in the practical aspects of risk management and macroprudential policy making. [ABSTRACT FROM AUTHOR]

The synthesis of triple‐layer‐structured polyaniline (PANI) conductive nanocomposites, including two‐dimensional leaf‐shaped and three‐dimensional flower‐shaped types (S‐PANI), via a two‐step method is proposed in this study. According to scanning electron microscopic measurement, the triple‐layer‐structured S‐PANI consists of a middle layer of nonconductive PANI (N‐PANI) at 100 nm thickness and emeraldine‐salt‐form PANI (ES‐PANI) nanolayer at 40–50 nm thickness. The results of Fourier‐transform infrared spectroscopy, UV/Vis spectroscopy, and X‐ray diffraction pattern demonstrate that the phenazine unit existed within the N‐PANI main chain, leading to the poor conductivity of N‐PANI. However, the conductivity of the N‐PANI can be extremely enhanced by at least nine orders of magnitudes (<10−9–100 S/cm) when a conductive ES‐PANI nanolayer is further grown on the N‐PANI outer surface. Finally, the results of oxygen transmission test and electrochemical impedance spectroscopy reveal that the leaf‐shaped S‐PANI, as an additive in epoxy resin, has the best oxygen barrier property (oxygen transmission rate = 5.86 cm3 m−2 day−1) and highest coating resistance (5.53 × 1010 Ω) after 60‐day immersion in 0.1 M HCl solution, indicating that the leaf‐shaped S‐PANI is an excellent anticorrosion additive. [ABSTRACT FROM AUTHOR]

Recent studies have shown the time trends of firm stock repurchase behavior. We examine these time changes for stock repurchase through the lens of real activities earnings management. Managers appear more likely to manipulate earnings through stock repurchases since the passage of the Sarbanes–Oxley Act (SOX) in 2002. Furthermore, suspect firms that just missed analyst earnings per share forecasts have higher incentives to manipulate earnings through stock repurchases. The results are not driven by changes in corporate governance associated with the passage of SOX. Overall, our results suggest earnings management can be a significant determinant of the dynamics of stock repurchases. [ABSTRACT FROM AUTHOR]

Producing good economic value in trading strategies for investors based on technical analysis is an issue of major interest in the academe and in practice. This study considers 9,555 trading rules and examines the usability of technical analysis. The double‐or‐out (DO) and the optimal‐portfolio (OP) strategies are used to investigate how investors construct their ass et allocation. The sample for empirical study is comprised of 20 major stock indexes from global markets as risky assets from 1998 to 2013. The DO strategy on average produces higher terminal wealth rather than does the buy‐and‐hold (BH) strategy, but the average utility (AU) of the former is worse than the latter. Nevertheless, using the OP strategy not only increases the terminal wealth of investors but also generates higher utility. Given a starting investment of one dollar and considering the best 100 trading rules, the DO and OP strategies result in average terminal wealth of 17.6 dollars and 5.9 dollars, respectively. In addition, in terms of AU, both of them are better than the BH strategy. These pieces of evidence demonstrate that investors who use an appropriate strategy of technical analysis in ass et allocation can produce good economic value, a finding that supports the continued use of technical analysis in practice. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we apply the Bitcoin to estimate the price of the Venezuelan bolivar, due to the unreliability of this currency's official exchange rate. Our approach is based on the triangular no‐arbitrage condition and takes the Bitcoin as an intermediate currency. To verify its validity, in addition to bolivars, six currencies are first considered in the empirical study. We find that trading through the Bitcoin market produces higher transaction costs or requires higher risk compensation than trading through the conventional exchange market. Then, we explore the Venezuelan case. Comparing the estimates of the black market bolivars, which are generated from several popular media sources and the Web site Dolartoday.com, using Bitcoin can produce reliable bolivar exchange rates quickly and easily. To sum up, we verify the feasibility of using the triangular no‐arbitrage condition in foreign exchange markets to estimate exchange rates through the Bitcoin. This is especially useful when capital controls exist such as they do in Venezuela. [ABSTRACT FROM AUTHOR]

ABSTRACT: In this work, the citronella oil (CTO)‐loaded composite microcapsules with hydroxyapatite (HAp)/quaternary ammonium salt of chitosan (HACC)/sodium alginate (SA) shells are facilely and effectively fabricated by templating citronella oil‐in‐water Pickering emulsions, which are stabilized with HAp nanoparticles. The microcapsule composite shells are prepared by the electrostatic adsorption of HACC and SA, and then chelation interaction of alginate and Ca2+ ions released from HAp nanoparticles. Scanning electronic microscope observation shows that the microcapsules have a spherical shape. Thereafter, Fourier transform infrared spectroscopy and thermal gravimetric analysis results indicate that CTO is successfully loaded into the microcapsules, and the related CTO‐loaded microcapsules possess the thermal stability. Moreover, the in vitro release study of CTO shows that the microcapsules have sustained release activity, and the related CTO release profiles can be well described by Rigter–Peppas model. The antimicrobial assays of microcapsules display the antibacterial effect of CTO‐loaded microcapsules against Staphylococcus aureus and Escherichia coli. Overall, this study opens up new potentiality for unstable active ingredient as an environmental friendly and ingenious microencapsulation in food and agriculture applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46386. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, well-monodispersed hollow latex particles were synthesized through semicontinuous seed emulsion polymerization, and the effect of the hollow latex particles' intermediate layer-core ratios on their morphology and opacity ability were studied. The results show that when the intermediate layer-core ratios increased from 6 to 10, the swelling degree of the hollow latex particles decreased, and the intensity gradually increased, but the opacity ability increased first and then decreased. When the intermediate layer-core ratio was 8, the opacity ability of the hollow latex particles was the best. When the intermediate layer-core ratios were 6 and 7, the surface of the hollow latex particles was rough, and they showed a great swelling degree, big cavity, and thin shell, and few of latex particles collapsed or ruptured. When the intermediate layer-core ratios were 9 and 10, the hollow latex particles had a smooth surface, thick shell, and small swelling degree and cavity, and roughly, there was no collapse or rupture of the hollow latex particles. When the intermediate layer-core ratio was 8, the swelling degree of the hollow latex particles was moderate. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42268. [ABSTRACT FROM AUTHOR]

The title reaction is only applicable to terminal propiolates. [ABSTRACT FROM AUTHOR]