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This study investigates whether and how federal judge ideology affects firm‐specific stock price crash risk. Using a comprehensive sample of US firms, we find a decline in the likelihood of future stock price crashes for firms headquartered in more liberal circuits. In identifying potential mechanisms, we show that liberal judge ideology reduces information opacity, risk‐taking behaviours and overinvestment, and thus curbs stock price crash risk. Furthermore, the curbing effect is more salient for firms with poor monitoring quality and those in low social capital areas. Overall, this study elucidates how federal judge ideology affects capital markets. [ABSTRACT FROM AUTHOR]

A family of chiral perylene diimides (PDIs) was newly developed as excellent circularly polarized luminescence (CPL) materials. They are asymmetrically derivatized with a double‐alkyl‐chained L‐ or D‐glutamate unit and a linear or branched alkyl chain. When water is added to the tetrahydrofuran (THF) solution of glutamate‐PDI‐linear‐alkyl chain compounds, kinetically formed H‐aggregates are formed in globular nanoparticles (NPs). These NPs undergo spontaneous transformation into thermodynamically stable nanotubes via helical nanostructures, which showed structured broad spectra originating from the strong coupling of delocalized Frenkel excitations (FE) and charge transfer excitations (CTE). Significant enhancement of circular dichroism (CD), fluorescence quantum yield, and circularly polarized luminescence (CPL) with luminescence dissymmetry factor (glum) are observed during the transformation of NPs to the FE/CTE‐coupled helical and tubular structures. This transformation process is significantly accelerated by applying physical stimuli, i.e. ultrasonication or adding helical aggregates as seed crystals, a feature unique to living supramolecular polymerization. Meanwhile, the branched chain‐containing PDIs only form H‐aggregates and did not show FE/CTE hybrid exciton states with living supramolecular polymerization properties. This study unveils that suitably designed chiral PDI derivatives show FE/CTE coupling accompanied by high fluorescence quantum yields, enhanced chiroptical properties, and supramolecular living polymerization characteristics. [ABSTRACT FROM AUTHOR]

Interactions between lone pairs and aromatic π systems are significant across biology and self‐assembled materials. Herein, employing an achiral confinement metal–organic framework (MOF) encapsulates guest molecules, it is successfully realized that lone pair (lp)‐π interaction induces fluorescence "turn‐on" and circularly polarized luminescence for the first time. The MOFs synthesized based on naphthalenediimide show nearly non‐emissive, which can be light‐up by introducing acetone or ester guests containing lone pairs‐π interaction. Furthermore, the introduction of a series of lp‐rich chiral esters induces supramolecular chirality as well as circularly polarized luminescence in achiral MOFs, while also observing chiral adaptability. This work first demonstrates the luminescence and chiral induction via lone pair electrons‐π interactions, presenting a fresh paradigm for the advancement of chiroptical materials. [ABSTRACT FROM AUTHOR]

This paper examines the impact of market related events and investor base on the spread of Bitcoin prices between two exchange platforms, Coinbase and Binance. Based on high‐frequency data samples collected from 2019 to 2021, we show how investors from different bases react differently to market related events, which create the price spreads between exchange platforms. We also identify the arbitrage opportunities these spreads create and establish arbitrage strategies for all identified events to exploit the variations in Bitcoin prices traded on both platforms. Findings indicate arbitrage offers profits that are higher overall than holding Bitcoin on either platform. [ABSTRACT FROM AUTHOR]

Chiral supramolecular living polymers with strongly coupled, delocalized Frenkel excitations (FE) and charge‐transfer excitations (CTE) were developed by Jianlei Han, Shigenori Fujikawa, and Nobuo Kimizuka in their Research Article (e202410431). Suitably designed, chiral perylene diimides (PDIs) show spontaneous transformation from kinetically formed nanoparticles into thermodynamically stable, luminescent helical and tubular nanostructures with enhanced chiroptical properties, fluorescence quantum yields, and living polymerization characteristics...By Jianlei Han; Shigenori Fujikawa and Nobuo KimizukaReported by Author; Author; Author [Extracted from the article]

Chiral supramolecular living polymers with strongly coupled, delocalized Frenkel excitations (FE) and charge‐transfer excitations (CTE) were developed by Jianlei Han, Shigenori Fujikawa, and Nobuo Kimizuka in their Research Article (e202410431). Suitably designed, chiral perylene diimides (PDIs) show spontaneous transformation from kinetically formed nanoparticles into thermodynamically stable, luminescent helical and tubular nanostructures with enhanced chiroptical properties, fluorescence quantum yields, and living polymerization characteristics...By Jianlei Han; Shigenori Fujikawa and Nobuo KimizukaReported by Author; Author; Author [Extracted from the article]

Creating a security material that carries distinct information in reflective color, fluorescence, and chiroptical property will enhance anti‐counterfeiting levels to deter counterfeits ranging from currencies to pharmaceuticals, but is proven extremely challenging. In this work, an advanced anti‐counterfeiting material, with three‐state of each mode reversibly converted into multi‐mode materials including reflective color, fluorescence, and circularly polarized luminescence signal, is constructed by loading photofluorochromic spiropyran (SP) and zinc ion (Zn2+) into the chiral liquid crystal. Under UV irradiation, the complexes of SP and Zn2+ will be transformed into merocyanine (MC) and MC‐Zn2+, while the energy transfer occurs from MC‐Zn2+ to MC. Upon heating, MC is easy to recover to SP, while the MC‐Zn2+ remains unchanged. The MC and MC‐Zn2+ can be transformed into the SP and Zn2+ under visible light irradiation. The three states of each mode can reversibly convert. Furthermore, the reflective color or fluorescence of each state shows different intensities under left‐ and right‐handed circular polarized filters, enabling easy distinguishing by naked eyes. The advanced anti‐counterfeiting method with multi‐state of each mode for multi‐mode encryption information output will provide a new concept for designing and fabricating multi‐mode anti‐counterfeiting materials, improving the security level for practical application. [ABSTRACT FROM AUTHOR]

Understanding the rules for designing anti‐Stokes emission induced by hot‐band absorption is crucial for developing novel materials for optical devices and biology. However, there are very few published reports on hot‐band‐absorption‐based single‐photon upconversion (HBA‐UC) materials, mainly because the rules for designing these molecules are poorly understood. Herein, HBA‐UC is investigated in a series of diarylethene derivatives (DAEs), namely benzothiophene S, S‐dioxide derivatives, which possess photochromic and photofluorochromic properties. All these DAEs show photoswitchable Stokes emission and HBA‐UC emission. Regulating the substituent groups enables flexibly adjustment of the HBA‐UC properties. Density functional theory (DFT) calculations reveal that the intramolecular charge transfer (ICT) between benzothiophene 1,1‐dioxide core and substituent groups is responsible for the emission properties of HBA‐UC. Furthermore, it is confirmed that the strong intensity of the ICT in DAEs can improve the scale of the anti‐Stokes shift. These findings provide a new direction for exploiting ICT feature in the design of HBA‐UC materials. [ABSTRACT FROM AUTHOR]

We investigate the role of culturally diverse board of directors on firm outcomes in China. We examine whether the diverseness of the educational, professional and cultural backgrounds of board members influences firm innovation. We find that firms whose directors have international experience are more innovative. In addition, the positive cultural diversity effect is more pronounced for returnee directors with postgraduate and science‐related degrees, and longer international work experience. Further, the directors who gain international experience from the countries with higher standards of management practice, corporate governance and intellectual property rights protection have a higher impact on corporate innovative activities. [ABSTRACT FROM AUTHOR]

Photofluorochromic diarylethene (DAE) molecules have been widely investigated due to their excellent fatigue resistance and thermal stability. However, the poor water solubility of DAEs limits their biological applications to some extent. Herein, we reported two kinds of water-dispersible DAE nanoparticles (DAEI-NPs and DAEB-NPs), in which DAE molecules were stabilized by the amphiphilic polymer DSPE-mPEG2000 using the nanoprecipitation approach. The fabricated nanoparticles retain well-controlled luminescence and fluorescence photoswitching properties in aqueous solution, which could be reversibly switched on and off under the alternating irradiation of ultraviolet (UV) and visible light. In addition, the closed-ring isomers of DAEB-NPs performed hot-band-absorption-based photon upconversion when excited by a 593.5 nm laser. Bearing excellent photophysical properties and low cytotoxicity, DAEB-NPs were applicable for upconversion cell imaging without high-excitation power density and free from oxygen removal. Additionally, the imaging process could be switched on by regulating the photofluorochromic nanoparticles. [ABSTRACT FROM AUTHOR]

Owing to its unique ability to efficiently convert low-energy photons into high-energy photons, triplet–triplet annihilation (TTA) based photon upconversion is a promising strategy for harvesting the low-energy tail of the solar spectrum for photovoltaic technologies. However, breaking through the upconversion quantum efficiency is not easy due to the few examples of existing annihilators that maximize the efficiency of singlet generation by TTA. Here, we present a new bichromophoric annihilator (PCP) that is paired with a metallic porphyrin as a sensitizer in low viscosity solution, and the system shows a record red-to-green external upconversion yield of 42%. This value can be achieved thanks to the photophysical properties of PCP that allow achieving a unitary triplet-to-singlet conversion efficiency and to its structural features that enable high fluorescence yields even at high concentrations. [ABSTRACT FROM AUTHOR]

Self‐assembled chiroptical materials have attracted considerable attention due to their great applications in wide fields. During the chiral self‐assembly, it remains unknown how achiral molecules can affect the assembly process and their final chiroptical performance. Herein, we report an achiral molecule directed chiral self‐assembly via halogen bonds, exhibiting not only an unprecedented chiral fractal architecture but also significantly amplified circularly polarized luminescence (CPL). Two axially chiral emitters with halogen bond sites co‐assemble with an achiral 1,4‐diiodotetrafluorobenzene (F4DIB) and well‐ordered chiral fractal structures with asymmetry amplification are obtained. The enhancement of the dissymmetry factors of the assemblies was up to 0.051 and 0.011, which was approximately 100 folds than those of the corresponding molecules. It was found that both the design of the chiral emitter and the highly directional halogen bond played an important role in hierarchically chirality transfer from chiral emitters to the micrometer scale chiral fractal morphology and amplified dissymmetry factors. We hope that this strategy can give a further insight into the fabrication of structurally unique featured highly efficient chiroptical materials. [ABSTRACT FROM AUTHOR]

We used robust skewness measures to revisit a recent theory that the average asymmetry (measured by the average monthly skewness values across firms) can negatively predict future market returns. Skewness measures employed in previous studies are moment‐based which are normally sensitive to outliers of returns. We thus consider a quantile‐based robust skewness measure and find that the predictive power of the average skewness to market returns no longer exists. Instead, we find a negative relation between the average expected (or ex‐ante) skewness and market returns, suggesting that investors' average expectation on skewness can negatively predict market returns. [ABSTRACT FROM AUTHOR]

Two axially chiral fluorophores derived from anthracene were designed and synthesized, and the chiroptical behaviour were thoroughly investigated including solvent‐dependent emission and circularly polarized luminescence (CPL). Interestingly, unexpected supramolecular self‐assembly of the chiral molecules driven by strong π−π interaction can enable significant hypsochromic shift and fluorescence intensity enhancement. Meanwhile, the luminescence dissymmetry factor of CPL activity exhibited significant enhancement through self‐assembly process. This work provides a novel approach to achieve the supramolecular CPL materials possessing both high luminescence quantum efficiency and high circular polarization. [ABSTRACT FROM AUTHOR]

A major trade‐off in the field of circularly polarized luminescence (CPL) of pure organic materials is that the large luminescence dissymmetry factor (glum) usually gives rise to the suppression of luminescence efficiency (ΦPL). Here, a supramolecular self‐assembled system, driven by arene–perfluoroarene (AP) interactions of chiral polycyclic aromatic hydrocarbons (PAHs) and octafluoronaphthalene (OFN), is reported to provide a solution to this problem. Two kinds of chiral PAHs based on pyrene and anthracene could co‐assemble with OFN in hybrid solvents to form long‐range‐ordered AP assemblies. The detailed process of AP interaction driving self‐assembly was verified by morphological measurements and fluorescence spectra. The AP assemblies exhibited chirality amplification not only in the excited state but also in the ground state. In addition, the AP assemblies showed an enhanced luminescence efficiency compared with the individual chiral PAHs due to the energy‐barrier effect of OFN. The present strategy based on AP interactions could be applied to boost the development of highly efficient CPL‐active materials. [ABSTRACT FROM AUTHOR]

In this article, we propose and construct a direct measure of investors' divergence of opinion based on auction bids data from private placements in China. We find that firms with higher bids dispersion generate lower long‐run stock returns after the issuance of private placements. This effect is economically significant and robust when controlling for market discount, earnings management, alternative dispersion measures, and self‐selection bias. Moreover, this negative relation is stronger for stocks with more stringent short‐sale constraints. Our findings therefore provide strong evidence for the overvaluation hypothesis. [ABSTRACT FROM AUTHOR]

Stable luminescent π-radicals with doublet emission have attracted growing attention for functional molecular materials. However, their chiroptical properties, particularly their doublet emission-based circularly polarized luminescence, have never been investigated. Here, we investigate the circularly polarized luminescence (CPL) properties of a series of achiral luminescent open-shell π-radicals through various chirality regulation approaches, including induction by a magnetic field, supramolecular coassembly and chiral liquid crystal encapsulation. [ABSTRACT FROM AUTHOR]

Achieving a large dissymmetry factor (glum) is a challenge in the field of circularly polarized luminescence (CPL). A chiral charge‐transfer (CT) system consisting of chiral electron donor and achiral electron acceptor shows bright circularly polarized emission with large glum value. The chiral emissive CT complexes could be fabricated through various approaches, such as grinding, crystallization, spin coating, and gelatinization, by simply blending chiral donor and achiral acceptor. The structural synergy originating from π–π stacking and strong CT interactions resulted in the long‐range ordered self‐assembly, enabling the formation of supramolecular gels. Benefiting from the large magnetic dipole transition moment in the CT state, the CPL activity of CT complexes exhibited large circular polarization. Our design strategy of the chiral emissive CT complexes is expected to help the development of new molecular engineering strategies for designing highly efficient CPL‐active materials. [ABSTRACT FROM AUTHOR]

A chiral zeolitic imidazolate framework (ZIF) showing circularly polarized luminescence (CPL) has been successfully constructed by blending binapthyl‐derived chiral emitters with ZIF‐8 rhombic dodecahedron nanoparticles. This approach solves a major trade‐off in CPL‐active materials: the large luminescence dissymmetry factor (glum) always suffers from suppression of luminescence efficiency. Compared to the optical properties of chiral emitters, the obtained chiral ZIF nanomaterials showed an enhanced fluorescence efficiency while the |glum| value is significantly amplified by one order of magnitude. Additionally, enantioselective fluorescence sensing in response to α‐hydroxycarboxylic acids has been enhanced in chiral ZIFs. Reorganization and conjunction of chiral emitters to the skeleton of ZIF nanoparticles can greatly improve both the luminescence quantum yield and circularly polarization, which facilitates the design of more efficient chiroptical materials. Knowing their left from right: A chiral zeolitic imidazolate framework showing circularly polarized luminescence has been successfully constructed. It can be used as an enantioselective fluorescence sensor for α‐hydroxycarboxylic acids. [ABSTRACT FROM AUTHOR]

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The Chinese capital market has attracted increasing academic attention due to its rising global influence, ongoing regulatory reforms, and distinct institutional background. In this paper, we review scholarly accounting and finance research pertaining to the Chinese capital market in Mainland China published in Tier 1 and Asia‐Pacific regional journals during the 1999–2018 period. Our review is based along four dimensions: top‐cited articles, main research fields, frequently contributing authors, and emerging research trends. We find that the increasing presence of China in global capital markets, along with its ongoing economic reforms, provides academics with opportunities to investigate distinct institutional environments and utilize natural experiments. This has led to the formulation of novel accounting and finance research questions, greatly advancing our understanding of accounting and finance research. [ABSTRACT FROM AUTHOR]

The orthogonal- or co-assembly of achiral perylene bisimide (PBI) with chiral gelators can be regulated by solvents. While the coassembly leads to the formation of chiroptical nanofibers through chirality transfer, the orthogonal assemblies could not. Moreover, protonation on the coassembled nanofibers could light up the circularly polarized luminescence (CPL). [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the net effect of a politically connected board for a firm. Using a natural experiment in China – a regulatory change to forbid bureaucrats from sitting on the board of public firms – we address the causality of the net effect of a politically connected board by testing the market reaction of the shares of firm targeted by the regulatory change to the policy announcement. The stocks of firms with politically connected directors who are targeted by the regulatory change show on average a significantly positive abnormal return, which suggests that the agency cost effect of a politically connected director dominates the value effect. The result is robust to various model settings and to a matched sample using the propensity score methodology. Additionally, the announcement effect of the resignation of a politically connected director is significantly positive, and significantly higher than that of a non‐connected director. Overall, our results suggest that the agency cost effect of a politically connected director dominates the value effect. [ABSTRACT FROM AUTHOR]

A hole-transport material (HTM), 1,1,2,2-tetrakis[4-(3,6-di- tert-butyl-9 H-carbazol-9-yl)phenyl]ethene (TTBCPE), was prepared straightforwardly and employed in the fabrication of perovskite solar cells (PSCs). The investigated HTM with tetraphenylethene as the core and tert-butylcarbazole as terminal units was synthesized in two steps from commercially available and cheap raw materials. The devices based on TTBCPE without the use of any dopants and additives exhibited a power conversion efficiency (PCE) of 12.65 %, which is comparable to 14.46 % obtained by using devices based on 2,2′,7,7′-tetrakis( N, N′ -di- p-methoxyphenylamino)-9,9′-spirobifluorene ( p-doped spiro-OMeTAD). Importantly, the device based on TTBCPE showed a higher stability than devices based on doped spiro-OMeTAD if stored under ambient conditions. In this regard, this easily synthesized and dopant-free system paves a new way to develop low-cost HTMs. [ABSTRACT FROM AUTHOR]

This paper provides a new explanation for investment-cash flow sensitivity from the perspective of CEO inside debt holdings. We examine the effect of CEO pensions and deferred compensation (inside debt) on investment-cash flow sensitivity for a sample of U. S. manufacturing firms from 2006 to 2012. We find that the firms with higher relative CEO leverage ratios ( CEO's debt/equity ratio scaled by the firm's debt/equity ratio) generate higher investment-cash flow sensitivity. Moreover, one standard deviation increase in the logarithm of the relative CEO leverage ratio enlarges investment-cash flow sensitivity by 50 per cent. This positive relationship still holds even after we take account of endogeneity and financial constraints. [ABSTRACT FROM AUTHOR]