We characterize cyclicity, convex-cyclicity, and supercyclicity for weighted composition operators and their adjoints on the harmonic Fock space. We formulate the criteria for cyclicity in terms of restrictions on the coefficient of the linear term in the composition symbol, with different phenomena in the analytic and conjugate-linear cases. We prove that convex-cyclicity can occur only in the rotational case, under suitable spectral separation conditions. We further show that a weighted composition operator is cyclic, respectively convex-cyclic, if and only if its adjoint has the corresponding property, and we also give descriptions of the cyclic and convex-cyclic vectors. Finally, we show that neither weighted composition operators nor their adjoints can be supercyclic on the harmonic Fock space. A key ingredient in the proofs is a complete determination of the eigenvalues and eigenvectors of the adjoint operator, a result that may be of independent interest. (c) 2026 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
The Valence-Consistent Shift (VCS) effect-a foundational principle in framing theory-holds that consumers generally respond more favorably to positively framed information than to negatively framed information. While this effect is well established in human-delivered service contexts, its applicability to AI-powered service encounters remains underexplored. This study investigates whether, and under what conditions, the VCS effect works in AI-powered services. Five studies demonstrate that positive attribute framing generally works better than negative attribute framing in promoting AI-powered services. However, this effect reverses when the service is personalized (vs. standardized) and may attenuate when the decision-maker is the service provider (vs. service receiver). Drawing on regulatory focus theory and processing fluency, we further identify the underlying psychological mechanism driving these effects. This research extends the VCS effect to AI-powered service contexts by identifying boundary conditions under which the effect is strengthened, weakened, or reversed. It also provides evidence that processing fluency helps explain how attribute framing interacts with AI-powered service contexts to influence customer response.
The development of efficient and low-cost sorbents for Direct Air Capture (DAC) of carbon dioxide (CO2) is essential to mitigate anthropogenic greenhouse gas emissions. In this study, olive pomace-derived biochar was functionalized with the ionic liquid 2-[2-hydroxyethyl (methyl) amino] ethanol chloride (MDEACl) using an ultrasound-assisted impregnation method. The effects of ionic liquid loading, stirring time, ultrasound amplitude, duty cycle, and sonication time on adsorption performance were systemically investigated. Physicochemical characterization by elemental and proximate analysis, Brunauer–Emmett–Teller (BET), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) confirmed the successful incorporation of MDEACl onto the biochar surface while preserving the carbonaceous structure. Although functionalization and subsequent degassing procedures led to a reduction in the apparent specific surface area and pore volume due to partial pore occupation, the introduction of nitrogen-containing active sites significantly enhanced CO2 adsorption. The optimum material was obtained with 1 wt% MDEACl and exhibited a CO2 uptake of ∼ 53 mg CO2 g−1 biochar under ambient air conditions (pCO2 = 0.00048 atm), reaching a maximum saturation capacity of ∼ 108.0 mg CO2 g⁻1 biochar at higher equilibrium partial pressures (pCO2 = 0.001773 atm), compared with 17.7 mg CO2 g⁻1 biochar for pristine biochar. Kinetic analyses showed that the adsorption process follows a hybrid mechanism involving rapid physisorption within the biochar pore network and reversible chemisorption through bicarbonate formation in the ionic liquid phase. The pseudo-second-order model provided the best fit to the experimental data (R2 = 0.999). Regeneration studies demonstrated promising multicycle stability under the evaluated conditions, with substantial recovery of adsorption capacity at a moderate temperature of 80 °C, suggesting potential for low-energy thermal regeneration. X-ray photoelectron spectroscopy (XPS) analyses confirmed the reversible formation of bicarbonate-like species and the long-term stability of MDEACl on the biochar surface. These results highlight ultrasound-functionalized biochar/MDEACl as a promising and energy-efficient adsorbent for DAC applications.
In this study, an iodine-free 1-butyl-3-methylimidazolium iodide (BmimI) ionic liquid, modified with acetonitrile (AN), was employed as a redox mediator using a facile approach to enhance DSSC performance. The optical properties of BmimI-AN(1:2) electrolyte (BmimI: AN = 1:2 w/w) indicate low absorption and high transmittance in the visible region. In addition to the UV-Vis spectra, Raman spectra also confirm the presence of the in-situ generated I_3^- ions, which are sufficient to complete the reaction mechanism in DSSCs. Conductivity measurements revealed that the BmimI-AN(1:2) electrolyte possesses excellent ionic conductivity compared to BmimI and standard commercial I^-/I_3^- electrolytes. The photovoltaic performances of the fabricated devices were analysed under simulated irradiation at an intensity of 100 mWcm–2 using a Xe lamp with an AM 1.5 filter. The BmimI-AN(1:2) electrolyte led to a higher power conversion efficiency (PCE) in DSSC, reaching up to 6.26 ± 0.21
The aim of this concise qualitative evidence synthesis is to identify qualitative research exploring how individuals 60 years and older with Autism Spectrum Disorder (ASD) experience their contact with healthcare services. Despite a comprehensive and systematic search, only one relevant study addressing the experiences of this population was identified. The study revealed that older adults with ASD face significant barriers in healthcare access, including feeling misunderstood, communication challenges related to literal thinking, and sensory sensitivities. Our concise evidence synthesis underscores a critical gap in the existing literature and underscores the need for further research regarding the specific needs of older adults with ASD.
