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Many firms use relative stock performance to evaluate and incentivize their CEOs. We document that such firms routinely disclose information that harms their peers' stock prices, and sometimes explicitly mention the harmed peers, by name, in these disclosures. Consistent with deliberate sabotage, peer‐harming disclosures appear to be aimed at peers whose stock price depressions are most likely to benefit the disclosing firms' CEOs. The pricing effect of these disclosures does not reverse, suggesting that the disclosures contain legitimate information regarding peers' prospects. In sum, our results suggest that relative performance evaluation in CEO pay motivates CEOs to internalize the externalities of their disclosures, and strategically disclose information that harms peers' stock prices, in order to improve their firms' relative standing within their peer group. [ABSTRACT FROM AUTHOR]

Ferroelectric thin films hold significant promise in various nanoelectronic applications, demanding precise control over their domain structures. While electrical field‐driven polarization switching is currently employed, it often leads to undesirable side effects. In contrast, mechanical switching offers a voltage‐free alternative but faces challenges in thicker films. Recent breakthroughs have demonstrated stable mechanical switching in films up to 200 nm thick, attributed to the presence of nanocavities. These nanoscale voids are believed to facilitate domain transitions, serving as essential pinning centers. In this study, mechanical domain switching in thick ferroelectric films is investigated using phase‐field modeling, with a specific focus on evaluating the influence of nanocavities on domain stability. The effects of cavity parameters (size, depth, and dielectric properties) on mechanical switching stability under various applied pressures are systematically examined. The findings reveal the intricate interplay between these factors and outline the conditions for stable mechanical switching. Furthermore, phase‐field simulations are employed to showcase the energetic mechanisms governing nanocavity‐assisted mechanical switching, while also highlighting the pivotal role of these defects as pinning centers. This investigation elucidates the nanocavity‐assisted mechanical control of polarization and the potential for optimizing thin film design through nanocavity engineering, thus enabling mechanical switching across substantial film thicknesses. [ABSTRACT FROM AUTHOR]

Transparent silica aerogel, serving as one typical porous and transparent material, possesses various unique features (e. g., large amounts of pores and interfaces, super-lightweight, super thermal insulation, low refractive index similar to gas), and it has attracted great attention in the fields of science, technology, engineering, art, and others. Transparency is one important evaluation index of transparent silica aerogel, and it was influenced by various factors such as raw materials, sol-gel reactions, phase separation, and drying methods. The structure design and fabrication of transparent silica aerogel is one huge and fine engineering. In this review, the optical/chemical guidance and design for the preparation of transparent silica aerogels are discussed, and typical applications, such as Cherenkov detectors, solar energy collection, lighting systems, and transparent fabric, were also discussed. Finally, a future outlook on the opportunities and challenges of transparent silica aerogels was proposed., (© 2024 Wiley-VCH GmbH.)

We analyze the radiative stability of the next-to-tribimaximal mixings (NTBM) with the variation of the SUSY breaking scale ( m S ) in MSSM, for both normal ordering (NO) and inverted ordering (IO) at the fixed input value of the seesaw scale M R = 1 0 15 GeV and two different values of tan β. All the neutrino oscillation parameters receive varying radiative corrections irrespective of the m S values at the electroweak scale, which are all within the 3 σ range of the latest global fit data at a low value of tan β. NO is found to be more stable than IO for all four different NTBM mixing patterns. [ABSTRACT FROM AUTHOR]

Neutrino masses are yet unknown. We discuss the present state of effective electron antineutrino mass from β decay experiments; effective Majorana neutrino mass from neutrinoless double-beta decay experiments; neutrino mass squared differences from neutrino oscillation: solar, atmospheric, reactor, and accelerator-based experiments; sum of neutrino masses from cosmological observations. Current experimental challenges in the determination of neutrino masses are briefly discussed. The main focus is devoted to contemporary experiments. [ABSTRACT FROM AUTHOR]

The strong suppression of equilibrium magnetic tunneling in a graphene/hBN/graphene heterostructure caused by the Coulomb correlation gap in the tunneling density of states has been found. Comparison has shown that the suppression of the equilibrium tunneling conductivity in a high magnetic field with a decrease in the temperature and the dependence of the observed gap width Δ on the filling factor of Landau levels ν are qualitatively similar to the respective results of similar experiments in GaAs heterostructures and has confirmed our hypothesis concerning the nature of the effect. However, the determined gap width Δ is much larger than those measured in all previous works in semiconductor heterostructures probably because the cyclotron energy in graphene is much higher than that in GaAs in the region of low Landau levels. [ABSTRACT FROM AUTHOR]

Smart windows with radiative heat management capability using the sun and outer space as zero-energy thermodynamic resources have gained prominence, demonstrating a minimum carbon footprint. However, realizing on-demand thermal management throughout all seasons while reducing fossil energy consumption remains a formidable challenge. Herein, an energy-efficient smart window that enables actively tunable passive radiative cooling (PRC) and multimode heating regulation is demonstrated by integrating the emission-enhanced polymer-dispersed liquid crystal (SiO 2 @PRC PDLC) film and a low-emission layer deposited with carbon nanotubes. Specifically, this device can achieve a temperature close to the chamber interior ambient under solar irradiance of 700 W m -2 , as well as a temperature drop of 2.3 °C at sunlight of 500 W m -2 , whose multistage PRC efficiency can be rapidly adjusted by a moderate voltage. Meanwhile, synchronous cooperation of passive radiative heating (PRH), solar heating (SH), and electric heating (EH) endows this smart window with the capability to handle complicated heating situations during cold weather. Energy simulation reveals the substantial superiority of this device in energy savings compared with single-layer SiO 2 @PRC PDLC, normal glass, and commercial low-E glass when applied in different climate zones. This work provides a feasible pathway for year-round thermal management, presenting a huge potential in energy-saving applications., (© 2024 Wiley‐VCH GmbH.)

The temperature dependency of photovoltaic power conversion efficiency (PCE) has been a key challenge to solar applications due to intrinsic processes. Herein, an alternative strategy is developed by modulating the solar light spectrum with a series of photonic hybrids. Transparent thin films are synthesized with the solutions of porphyrin compounds and iron oxides which exhibit strong absorptions in the UV and IR regions. These spectral modulating thin films are photonically tuned via compositional optimization to absorb photons near 400 nm and above 1127 nm from solar spectrum to reduce thermalization and sub‐bandgap absorption. These spectral modulators are applied in a particular configuration above a commercial silicon panel to partially filter the simulated solar light. The PCE of the silicon panel suffers a significant decrease due to temperature increase from 22.9 to 92.9 °C after 60 min solar irradiation, resulting in a PCE decrease from 25.1% to 16.3%. With the transparent spectral modulators, upon solar irradiation for 60 min, the maximum PCE has maintained at 20.5%. The mechanisms of PCE enhancement are identified based on reduced thermalization and sub‐bandgap absorption. [ABSTRACT FROM AUTHOR]

Piezoresponse force microscopy (PFM) is used for investigation of the electromechanical behavior of the head‐to‐head (H‐H) and tail‐to‐tail (T‐T) domain walls on the non‐polar surfaces of three uniaxial ferroelectric materials with different crystal structures: LiNbO3, Pb5Ge3O11, and ErMnO3. It is shown that, contrary to the common expectation that the domain walls should not exhibit any PFM response on the non‐polar surface, an out‐of‐plane deformation of the crystal at the H‐H and T‐T domain walls occurs even in the absence of the out‐of‐plane polarization component due to a specific form of the piezoelectric tensor. In spite of their different symmetry, in all studied materials, the dominant contribution comes from the counteracting shear strains on both sides of the H‐H and T‐T domain walls. The finite element analysis approach that takes into account a contribution of all elements in the piezoelectric tensor, is applicable to any ferroelectric material and can be instrumental for getting a new insight into the coupling between the electromechanical and electronic properties of the charged ferroelectric domain walls. [ABSTRACT FROM AUTHOR]

Combating fake news about the stock market is a major issue in the social media era. We examine the impact of a firm's social media fake news clarification on the PEAD using a 2010 Chinese policy experiment, which enabled firms to promptly respond to fake rumors on social media platforms. We find that a firm's clarification of fake news on social media is negatively associated with PEAD, and its effect varies with certain dimensions of firm characteristics. Our evidence suggests that firms can play an active role in combating fake news on social media and in improving information efficiency in the stock market. [ABSTRACT FROM AUTHOR]

Integrating photovoltaic (PV) perovskite solar cells and photothermal (PT) collectors into a hybrid photovoltaic thermal (PVT) is a promising method to further improve the conversion efficiency of solar energy via salvaging the near‐infrared energy. Herein, a 1D photonic crystal of Si/GeO2 to construct a spectrally selective PV–PT splitter that selectively reflects solar energy in the PV band while absorbing the rest is utilized. The fabricated PV–PT splitter reveals a considerable reflectance of 92.3% in the PV band, a comprehensive absorptance of 52.1% in the PT band, as well as good angular independence over a wide incident range of 0–70°. The hybrid PVT design with the Si/GeO2 spectral splitter/absorber and a perovskite solar cell (PSC) acquires a solar‐to‐electrical efficiency of 29.3% higher than the single PSC (24.6%). In addition, the temperature of PSCs in the hybrid PVT design under 1 kW m−2 solar irradiation can be significantly reduced by 15 °C owing to suppression of ineffectively converted incident photons on the PV cells. This appealing strategy highlights a new avenue for further enhancing the total electrical efficiency via broadening the utilization of the entire solar spectrum in the hybrid PVT design integrated with wide‐bandgap perovskite solar cells. [ABSTRACT FROM AUTHOR]

The fear of an increase in blood sugar can be very traumatic. Being diabetic either type I or type II leads to a disorder called diabetes distress having traits of stress, depression, and anxiety. Among risk factors of diabetes mellitus heavy and trace metal toxicity emerges as new risk factors reported in many studies. In this study we target toxic metals, viz., Ni 2+ , Zn 2+ , and Cu 2+ , involved in the pathogenesis of diabetes and diabetic stress with naphthazarin esters. The compounds C1-C3 isolated from the leaves and roots of Arnebia guttata were tested for their metal-binding ability in an aqueous medium in UV-Visible and nuclear magnetic resonance (NMR) studies. These probes are well-known naphthoquinones present in the Arnebia species. In the UV-Visible titrations of compounds C1-C3 with Na 2+ , K 2+ , Zn 2+ , Ca 2+ , Cu 2+ , Mg 2+ , Co 2+ , and Ni 2+ ions, significant binding was observed with Ni 2+ , Cu 2+ , and Zn 2+ ions in MeOH/H 2 O. There occurs a beautiful formation of red-shifted bands between the 520 to 620 nm range with a synergistic increase in absorbance. Also, the disappearance of proton peaks in the 1 H NMR spectrum on addition of metal ions confirmed binding. Compounds C1-C3 isolated from A. guttata came out as potent Ni 2+ , Zn 2+ , and Cu 2+ sensors that are reportedly involved in islet function and induction of diabetes., (© 2024 John Wiley & Sons Ltd.)

A spectral splitter plays a crucial role in the hybrid photovoltaic (PV)–thermal design for efficient solar energy harvesting. Herein, the lossy medium periodic structure of ITO/Si is utilized to construct a novel spectral splitter/absorber that selectively reflects the solar energy in PV band while absorbing the rest of solar energy. The as‐prepared spectral splitter/absorber demonstrates a weighted reflectance of 75.6% in the PV band, an absorptance of 83.1% in the photothermal (PT) band, as well as superior angular performance across a broad incident range of 0°–60°. The proposed hybrid photovoltaic–thermal (PVT) system assembled with the spectral splitter/absorber with 1100 nm long edge of the PV band enhances the total electrical efficiency to 26.5%, higher than that of the individual Si PV cell (19.1%), resulting from the precise modulation of solar spectrum via the splitter/absorber to realize efficient utilization of solar energy in different bands. The temperature of PV cells in a hybrid PVT system also declines by ≈25 °C compared with the single‐Si PV cell. The PV band can be easily shifted to match other narrow‐bandgap PV cells due to intrinsic properties of near‐zero k of both ITO and Si at near‐infrared wavelength range and the large difference in n between them. [ABSTRACT FROM AUTHOR]

Smart windows can selectively regulate excess solar radiation to reduce heating and cooling energy consumption in the built environment. However, the inevitable dissipation of ultraviolet and near‐infrared into waste heat results in inefficient solar utilization. Herein, a dual‐band selective solar harvesting (SSH) window is developed to realize full‐spectrum utilization. A transparent photovoltaic, converting ultraviolet into electricity, and a transparent solar absorber, converting near‐infrared into thermal energy, are integrated and coupled with a ventilation system to extract heat for indoor use. Compared with common transparent photovoltaics, the SSH window increases solar harvesting efficiency up to threefold while maintaining a considerable visible transmittance. Simulations suggest that the SSH window, besides generating electricity, delivers energy savings by over 30% higher than common smart windows. This is the first integration of transparent photovoltaic and transparent solar absorber into a window, which may open up a new avenue for the development of energy‐efficient buildings. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a lethal disease that involves the progressive annihilation of motor neurons. In a preclinical setting, sensitive functional testing is required to detect malfunctioning motor behavior in the SOD1G93A transgenic mouse model of ALS. Earlier, we reported the restoration of motor processivity upon gold nano-chaperon treatment in vitro that was dampened upon the exogenous addition of proteotoxic A4V SOD1. In the present in vivo study, we evaluated the pharmacological potential of a synthesized Au-PEG nanoconjugate in transgenic SOD1G93A mice. We found differences in the detection of the onset of symptoms and the progression of the disease upon Au-PEG treatment when assessed using behavioral tests, such as rotarod and walking tests. Additionally, the gastrocnemius muscle histopathology showed notable alteration upon Au-PEG administration. The therapeutic potential of the nanoconjugate was found to be notable, with additional survival for ∼1 week, a delayed mean age at onset, and improved rotarod performance. Furthermore, molecular docking studies reveal that the addition of the lethal A4V SOD1 mutant to the tubulin dimer has a negative impact on the binding of the kinesin motor to tubulin (Kd = 1.4 × 10−7 mol L−1vs. Kd = 2.5 × 10−9 mol L−1), whereas the exogenous addition of gold nanoparticles (Au NPs) to the protein complex of A4V SOD1–tubulin has a substantially positive effect on the binding affinity of kinesin to the tubulin dimer (Kd = 2.7 × 10−12 mol L−1), reinstating the dynamics as a result. Thus, the engineering of self-therapeutic gold nanoparticles for combinatorial therapy holds potential and, therefore, the role of Au NPs in modifying the state of ALS deserves further investigation, with the eventual aim of managing the complex disease ALS. [ABSTRACT FROM AUTHOR]

We report the demonstration of defect-assisted tunneling spectroscopy of the electronic band structure in twisted bilayer graphene (tBLG)/hexagonal boron nitride (h-BN) moiré superlattices in which the moiré period between the two graphene layers is close to that between the graphene and h-BN layers. We measured both the in-plane and vertical carrier transport in the tBLG/h-BN van der Waals (vdW) tunneling device. The moiré periods were determined from the in-plane carrier transport measurements. The observed vertical tunneling transport characteristics indicated that resonant tunneling occurs from the graphite electrode to tBLG through localized defect states in the h-BN tunnel barrier. We observed multiple defect-assisted resonant tunneling trajectories, from which we derived the density of states (DOS) for tBLG. The obtained DOS has broad flatband features, in qualitative agreement with the theoretical predictions. Furthermore, we obtained three types of DOS, suggesting that we probed local band structures corresponding to AA, AB/BA, and domain wall sites in tBLG. Thus, defect-assisted tunneling spectroscopy has potential as a tool to determine the local band structures in twisted 2D vdW materials. [ABSTRACT FROM AUTHOR]

Although spectrally selective materials play a key role in existing and emerging solar thermal technologies, temperature‐related degradation currently limits their use to below 700 °C in vacuum and even lower temperatures in air. Here a solar‐transparent refractory aerogel that offers stable performance up to 800 °C in air is demonstrated, which is significantly greater than its silica counterpart. This improved stability is attributed to the formation of a refractory aluminum silicate phase, which is synthesized using a conformal single cycle of atomic layer deposition within the high‐aspect‐ratio pores of silica aerogels. Based on direct heat loss measurements, the transparent refractory aerogel achieves a receiver efficiency of 75% at 100 suns and an absorber temperature of 700 °C, which is a 5% improvement over the state of the art. Transparent refractory aerogels may find widespread applicability in solar thermal technologies by enabling the use of lower‐cost optical focusing systems and eliminating the need for highly evacuated receivers. In particular, a shift to higher operating temperatures while maintaining a high receiver efficiency can enable the use of advanced supercritical CO2 power cycles and ultimately translate to an ≈10% (absolute) improvement in solar‐to‐electrical conversion efficiency relative to existing linear concentrating systems. [ABSTRACT FROM AUTHOR]

We demonstrate twist-controlled resonant tunneling in a monolayer graphene (MLG)/hexagonal boron nitride (h-BN)/ABA-stacked trilayer graphene (TLG) van der Waals (vdW) junction, in which MLG and TLG flakes are aligned with a small twist angle θ of ∼1.05° between their crystallographic orientations through a thin h-BN barrier. Owing to the small interlayer twist, resonant tunneling attributed to the conservation of momentum and energy was observed between the single linear band of MLG and multiple subbands of TLG. We show that different subbands of TLG—bilayer-graphene-like subbands and a MLG-like subband—exhibit distinctly different resonant tunneling behaviors. Therefore, we demonstrate subband-resolved resonant tunneling. This technique provides a method to determine band parameters (Slonczewski–Weiss–McClure parameters) and probes the band dispersion of different two-dimensional materials by utilizing a MLG electrode. [ABSTRACT FROM AUTHOR]