ABSTRACT
By analyzing a large panel of elections in 55 countries, we show that political uncertainty surrounding elections can affect asymmetric cost responses to activity changes (i.e., cost ...stickiness). In comparison to non‐election years, we find that the asymmetry in cost behaviors is stronger during election years in regressions that control for other firm‐level and country‐level determinants. In another series of tests, we report strong, robust evidence supporting the predictions that the importance of political uncertainty to cost stickiness is concentrated in countries with sound political and legal institutions. Collectively, the results imply that managers retain slack resources when political uncertainty is high but to be resolved soon.
RÉSUMÉ
Incertitude politique et rigidité des coûts : Données probantes tirées d’élections nationales dans le monde entier
Dans le cadre de l'analyse d'un vaste éventail d’élections tenues dans 55 pays, nous montrons que l'incertitude politique entraînée par des élections peut avoir une incidence sur les réactions asymétriques au niveau des coûts à la suite de changements aux activités (c.‐à‐d., la rigidité des coûts). Nous avons découvert que, dans le cadre d'analyses de régression qui tiennent compte d'autres déterminants à l’échelle de la société et du pays, l'asymétrie de l’évolution des coûts est plus importante durant les années électorales que durant les années non électorales. Dans le cadre d'une autre série de tests, nous présentons des preuves solides et convaincantes à l'appui des prévisions voulant que l'influence de l'incertitude politique sur la rigidité des coûts se manifeste principalement dans les pays dotés de solides institutions politiques et juridiques. Globalement, les résultats donnent à penser que les gestionnaires conservent des ressources excédentaires lorsque l'incertitude politique est élevée mais qu'elle se résorbera rapidement.
Recent technological advances in developing a diverse range of lasers have opened new avenues in material processing. Laser processing of materials involves their exposure to rapid and localized ...energy, which creates conditions of electronic and thermodynamic nonequilibrium. The laser‐induced heat can be localized in space and time, enabling excellent control over the manipulation of materials. Metal oxides are of significant interest for applications ranging from microelectronics to medicine. Numerous studies have investigated the synthesis, manipulation, and patterning of metal oxide films and nanostructures. Besides providing a brief overview on the principles governing the laser–material interactions, here, the ongoing efforts in laser irradiation of metal oxide films and nanostructures for a variety of applications are reviewed. Latest advances in laser‐assisted processing of metal oxides are summarized.
Laser irradiation has emerged as an effective and reliable fabrication approach for the synthesis, manipulation, and patterning of metal oxides. A comprehensive overview is provided regarding the laser‐assisted tailoring of the functionality of metal oxide films and nanostructures for a wide range of applications. In addition, current progress and latest advances in the laser processing of metal oxides are summarized.
A large literature in finance provides evidence that agency conflicts and information asymmetry between managers and outsiders lead firms to undertake suboptimal levels of investment (Hubbard 1998 ...and Stein 2003 provide surveys of this literature). Recent accounting research builds on this notion in arguing that high-quality financial reporting can serve to mitigate such market imperfections and improve investment efficiency (e.g., Bushman and Smith 2001; Healy and Palepu 2001; Lambert, Leuz, and Verrecchia 2007). Consistent with this argument, a growing body of empirical evidence suggests that high-quality accounting is associated with more efficient capital investments (e.g., Biddle and Hilary 2006; McNichols and Stubben 2008; Biddle, Hilary, and Verdi 2009). We extend this line of research by examining investments in labor, an important factor of production that has been largely overlooked by previous literature. We posit that high-quality financial reporting leads to more efficient investments in labor by mitigating market frictions that stem from information asymmetry between managers and outside capital suppliers.
Glia contribute to synapse elimination through phagocytosis in the central nervous system. Despite the important roles of this process in development and neurological disorders, the identity and ...regulation of the "eat‐me" signal that initiates glia‐mediated phagocytosis of synapses has remained incompletely understood. Here, we generated conditional knockout mice with neuronal‐specific deletion of the flippase chaperone Cdc50a, to induce stable exposure of phosphatidylserine, a well‐known "eat‐me" signal for apoptotic cells, on the neuronal outer membrane. Surprisingly, acute Cdc50a deletion in mature neurons causes preferential phosphatidylserine exposure in neuronal somas and specific loss of inhibitory post‐synapses without effects on other synapses, resulting in abnormal excitability and seizures. Ablation of microglia or the deletion of microglial phagocytic receptor Mertk prevents the loss of inhibitory post‐synapses and the seizure phenotype, indicating that microglial phagocytosis is responsible for inhibitory post‐synapse elimination. Moreover, we found that phosphatidylserine is used for microglia‐mediated pruning of inhibitory post‐synapses in normal brains, suggesting that phosphatidylserine serves as a general "eat‐me" signal for inhibitory post‐synapse elimination.
SYNOPSIS
Neuronal‐specific deletion of the flippase chaperone Cdc50a leads to exposure of phosphatidylserin on neuronal outer membranes causing specific loss of inhibitory post‐synapses and seizures. Microglial phagocytosis via the phagocytic receptor MERTK promotes inhibitory post‐synapse elimination in Cdc50a cKO brains. Inhibitory post‐synapses in normal juvenile brains also use phosphatidylserine for synapse elimination, suggesting that phosphatidylserine exposure functions as an “eat‐me” signal for microglia‐dependent inhibitory post‐synapse elimination.
Neuronal Cdc50a deletion induces rapid lethality with appearance of audiogenic seizure.
Neuronal Cdc50a deletion causes the specific loss of inhibitory post‐synapses without affecting other synapses.
Ablating microglia or deleting microglial Mertk rescues the loss of inhibitory post‐synapses and seizure behaviors in Cdc50a cKO mice.
Microglial Mertk deletion increases the number of phosphatidylserine‐exposed inhibitory post‐synapses in the wild‐type juvenile brains.
Mouse models with increased neuron‐specific exposure of an apoptotic cell‐defining phospholipid provide insight into the nature of the "eat‐me" signal and its recognition during synapse elimination.
Labor Unions and Income Smoothing Hamm, Sophia J. W.; Jung, Boochun; Lee, Woo‐Jong
Contemporary accounting research,
09/2018, Letnik:
35, Številka:
3
Journal Article
Recenzirano
We study labor unions, an important stakeholder group that has not been a focus of the earnings smoothing literature. We posit that managers strike a balance between sheltering resources from ...employees’ profit sharing demands and catering to employees’ aversion to downside risk by smoothing earnings. We then hypothesize that a strong labor union would intensify managerial incentives to smooth earnings. Consistent with our hypothesis, we find that union strength is positively associated with earnings smoothing activities through management of both accruals and R&D expenditures.
Syndicats et lissage des résultats
Les auteurs étudient les syndicats, un groupe important de parties prenantes auquel ne se sont pas attardés les chercheurs intéressés par la question du lissage des résultats. Ils avancent que, grâce au lissage des résultats, les gestionnaires parviennent à un équilibre dans leurs efforts pour mettre les ressources à l'abri des demandes de participation aux résultats des employés et remédier à l'aversion de ces derniers à l’égard du risque de perte. Les auteurs font ensuite l'hypothèse qu'un syndicat fort intensifiera la propension des gestionnaires à lisser les résultats. Conformément à cette hypothèse, ils constatent que la force du syndicat affiche un lien positif avec les activités de lissage des résultats au moyen de la gestion des régularisations aussi bien que des dépenses de R&D.
Influenza viruses (IVs) have become increasingly resistant to antiviral drugs that target neuraminidase and matrix protein 2 due to gene mutations that alter their drug-binding target protein ...regions. Consequently, almost all recent IV pandemics have exhibited resistance to commercial antiviral vaccines. To overcome this challenge, an antiviral target is needed that is effective regardless of genetic mutations.
In particular, hemagglutinin (HA), a highly conserved surface protein across many IV strains, could be an effective antiviral target as it mediates binding of IVs with host cell receptors, which is crucial for membrane fusion. HA has 6 disulfide bonds that can easily bind with the surfaces of gold nanoparticles. Herein, we fabricated porous gold nanoparticles (PoGNPs) via a surfactant-free emulsion method that exhibited strong affinity for disulfide bonds due to gold-thiol interactions, and provided extensive surface area for these interactions. A remarkable decrease in viral infectivity was demonstrated by increased cell viability results after exposing MDCK cells to various IV strains (H1N1, H3N2, and H9N2) treated with PoGNP. Most of all, the viability of MDCK cells infected with all IV strains increased to 96.8% after PoGNP treatment of the viruses compared to 33.9% cell viability with non-treated viruses. Intracellular viral RNA quantification by real-time RT-PCR also confirmed that PoGNP successfully inhibited viral membrane fusion by blocking the viral entry process through conformational deformation of HA.
We believe that the technique described herein can be further developed for PoGNP-utilized antiviral protection as well as metal nanoparticle-based therapy to treat viral infection. Additionally, facile detection of IAV can be achieved by developing PoGNP as a multiplatform for detection of the virus.
Generally, an LLC series resonant converter (LLC SRC) is an attractive topology for applications, which require wide input variation and high conversion efficiency because of its wide gain capability ...and soft-switching capability. However, there is a regulation problem in which the output voltage increases as the load current decreases. In this paper, Bode plot and impedance asymptote analysis were conducted to obtain an intuitive sense of the regulation characteristic of LLC SRC under the light-load condition. Moreover, to improve the regulation capability, a new resonant tank with an additional capacitor is proposed. Its design guidelines were determined by Bode plot and impedance asymptote analysis. Therefore, the proposed LLC SRC achieves very light load regulation, while it maintains the advantages of typical LLC SRCs.
Narrow‐bandgap mixed Pb‐Sn perovskite solar cells (PSCs) have great feasibility for constructing efficient all‐perovskite tandem solar cells, in combination with wide‐bandgap lead halide PSCs. ...However, the power conversion efficiency of mixed Pb‐Sn PSCs still lags behind lead‐based counterparts. Here, additive engineering using ionic imidazolium tetrafluoroborate (IMBF4) is proposed, where the imidazolium (IM) cation and tetrafluoroborate (BF4) anion efficiently passivate defects at grain boundaries and improve crystallinity, simultaneously relaxing lattice strain, respectively. Defect passivation is achieved by the chemical interaction between the IM cation and the positively charged under‐coordinated Pb2+ or Sn2+ ions, and lattice strain relaxation is realized by lattice expansion with the intercalation of BF4 anions into the perovskite lattice. As a result, the synergistic effects of the cation and anion in the IMBF4 additive greatly enhance the optoelectronic performance of half‐mixed Pb‐Sn perovskites, leading to much longer carrier lifetimes. The best‐performing half‐mixed Pb‐Sn PSC shows an efficiency above 19% with negligible hysteresis, while retaining over 90% of its initial efficiency after 1000 h in a nitrogen‐filled glovebox and showing a lifetime to 80% degradation of 53.5 h under continuous illumination.
Half‐mixed Pb‐Sn perovskite solar cells with significantly improved performance and stability are prepared by introducing an ionic imidazolium tetrafluoroborate additive. The synergistic effects of IM cation and tetrafluoroborate anion enable efficient defect passivation at grain boundaries, reducing leakage current, and enlargement in grain size with relaxed lattice strain simultaneously, thereby exerting a remarkable impact on device performance and stability.
This paper proposes a new antiwindup strategy for PI speed controller to suppress the undesired side effect known as integrator windup when large set-point changes are made. When the speed control ...mode is changed from P control to PI control, an appropriate initial value for the integrator is assigned. This value then restricts the overshoot. In addition, the proposed method guarantees the designed performance independent of the operating conditions, i.e., different set-point changes and load torques, and can be easily implemented with existing PI controllers. In SIMULINK/MATLAB-based comparative simulations and experiments for a permanent-magnet synchronous motor speed controller, the proposed method shows a superior control performance compared with the existing well-known antiwindup methods, such as conditional integration and tracking back calculation.
The rapid transmission and numerous re‐emerging human influenza virus variants that spread via the respiratory system have led to severe global damage, emphasizing the need for detection tools that ...can recognize active and intact virions with infectivity. Here, this work presents a plasmonic vesicle‐mediated fusogenic immunoassay (PVFIA) comprising gold nanoparticle (GNP) encapsulating fusogenic polymeric vesicles (plasmonic vesicles; PVs) for the label‐free and colorimetric detection of influenza A virus (IAV). The PVFIA combines two sequential assays: a biochip‐based immunoassay for target‐specific capture and a PV‐induced fusion assay for color change upon the IAV–PV fusion complex formation. The PVFIA demonstrates excellent specificity in capturing the target IAV, while the fusion conditions and GNP induce a significant color change, enabling visual detection. The integration of two consecutive assays results in a low detection limit (100.7919 EID50 mL−1) and good reliability (0.9901), indicating sensitivity that is 104.208 times higher than conventional immunoassay. Leveraging the PV viral membrane fusion activity renders the PVFIA promising for point‐of‐care diagnostics through colorimetric detection. The innovative approach addresses the critical need for detecting active and intact virions with infectivity, providing a valuable tool with which to combat the spread of the virus.
This work presents a plasmonic vesicle‐mediated fusogenic immunoassay (PVFIA) for the label‐free and colorimetric detection of influenza A virus (IAV). PVFIA demonstrates excellent specificity in capturing the target, while the fusion assay with gold nanoparticle (GNP) encapsulating fusogenic plasmonic vesicles (PVs) enables visual detection. The results show a low detection limit (100.7919 EID50 mL−1) and good reliability (0.9901), indicating sensitivity 104.208 times higher than conventional immunoassay.
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