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Artificial particles and soil communities interactively change heterospecific plant-soil feedbacks
No full textBackground and aims
Microplastics affect plant growth and change abiotic and biotic soil properties, such as soil structure and soil-community composition. However, how microplastics affect plant-soil interactions, such as plant-soil feedbacks (PSFs), is still poorly understood. Here, we tested how artificial particles affect heterospecific PSFs, depending on an intact or depleted soil community.
Methods
We conducted a two-phase-greenhouse experiment using Centaurea jacea to condition soil containing an intact or initially depleted (by sterilization) soil community in the first phase. Subsequently, we grew individuals of Crepis biennis and Eragrostis minor in all combinations of soil conditioning (presence or absence of C. jacea in the first phase), soil-community status, and different material treatments including no added particles, glass particles, or three microplastics individually and mixed. Effects of soil community, material treatment and their interaction on PSFs were assessed based on plant biomass and root-morphology traits.
Results
Particles in general, microplastics and glass, strengthened PSFs based on plant biomass. PSFs tended to be negative with the intact but positive with the initially depleted soil community. Overall, particle-addition effects on PSFs were stronger in the initially depleted community, indicating interactive effects of artificial particles in the soil and soil biota. Interactive particle and soil-community effects generally depended on material type and concentration.
Conclusion
Our findings indicate that artificial particles can affect heterospecific PSFs and that these effects are likely to be partly mediated by the initial soil community. Further, they highlight the need for studies assessing potential ecological implications of microplastics on plant-soil interactions.publishe
Prevalence and risk factors of mental health symptoms of individuals in different detention settings : a cross-sectional study
No full textBackground
The prevalence of mental health symptoms is substantially higher in incarcerated individuals than in the general public. However, little is known how different types of incarceration, including pre-trial and correctional detention as well as detention exclusively for deportation proceedings (administrative detention), are associated with mental health symptoms. We aimed to investigate the prevalence of mental health symptoms in this vulnerable population and examine the impact of different types of detention as well as risk factors on their mental health symptoms.
Methods
Combining two cross-sectional surveys, we assembled a diverse sample of adult individuals incarcerated in the Canton of Zurich, Switzerland. The surveys were conducted in police detention facilities for provisional arrest and in correctional, pre-trial, and administrative detention facilities between July and October 2022 and 2023, respectively. We employed the brief symptom checklist (BSCL) to assess current mental health symptoms, and demographic questionnaires captured relevant risk factors. Logistic regression models were used to examine associations with mental health symptoms.
Results
Of the eligible N = 1,868 individuals, N = 951 provided sufficient data (completion rate = 50.9%). Our samples were largely representative regarding age, sex, and type of incarceration. Prevalence estimates revealed that almost half of the incarcerated individuals experienced clinically relevant mental health symptoms (44.9%, 95% uncertainty interval (UI): 41.7–48.1%). Risk factors included age, gender, and prior mental health treatment, with younger individuals, female and individuals identifying as non-binary, as well as those who have been treated for a mental health problem before at a two- to threefold greater risk than their counterparts. Types of incarceration demonstrated distinct associations, with individuals in provisional arrest and administrative detention facing a fourfold greater risk.
Conclusions
Our findings underscore the substantial prevalence of mental health symptoms among incarcerated individuals and highlight specific risk factors associated with this vulnerable population. Addressing the mental health needs of female and individuals indentifying as non-binary, and those in provisional arrest or administrative detention is crucial for effective correctional practices. These insights underline the importance of implementing standard screening procedures and tailored interventions to improve mental health outcomes in diverse detention settings.publishe
Short-term functions and long-term consequences of body checking as a transdiagnostic phenomenon across eating disorders, body dysmorphic disorder, and illness anxiety disorder : a systematic review
No full textBody checking refers to the repeated evaluation of one’s own body. As a safety mechanism, it is prevalent in various mental disorders, including eating disorders, body dysmorphic disorder, and illness anxiety disorder. While the type and manner of body checking behavior may differ between these disorders, cognitive-behavioral models highlight similar mechanisms underlying this behavior. According to the models, body checking is assumed to arise in response to negative affect, offer immediate relief, and increase psychopathology in the longer term as a mechanism of negative reinforcement. The objective of this review is to empirically evaluate these assumptions for eating disorders, body dysmorphic disorder, and illness anxiety disorder. Therefore, we conducted a systematic literature review across four electronic databases, with N = 43 studies meeting the inclusion criteria. The assumption that body checking occurs in response to negative affect was supported. However, findings regarding its short- and long-term role in maintaining negative affect were inconsistent. Therefore, our results may suggest the need to re-evaluate the etiologically proposed negative reinforcement mechanism of body checking in eating disorders, body dysmorphic disorder, and illness anxiety disorder. To facilitate the interpretation of study findings, future studies should distinguish between short- and long-term effects of body checking.publishe
How does inflation affect different age groups?
No full textWe develop an overlapping-generations model with sticky wages and prices to study the socially optimal inflation rate in the long term. While sticky prices and firms’ productivity growth would yield a positive optimal inflation rate, we show that sticky wages, in combination with empirically plausible changes in productivity over workers’ lives, make moderate deflation optimal. We also study intergenerational conflicts and show that younger voters gain from lower inflation, whereas older voters prefer higher inflation.publishe
Deciphering the underlying repercussions of cognitive overload on university students' fatigue, frustration and academic productivity : Implementation of stimulus–organism–response model
No full textExtant studies suggest that cognitive overload, as a nascent phenomenon, has become increasingly pervasive among university students, precipitating a multitude of detrimental consequences. Nevertheless, the adverse impacts of cognitive overload, particularly on Chinese higher education students, remain markedly underexplored in the extant literature. To improve academic understanding, this research combines quantitative data with the stimulus–organism–response (SOR) framework, constructing a robust theoretical model that elucidates the antecedents and sequelae of cognitive overload in relation to academic productivity in educational contexts. Research has suggested that several types of cognitive overload, including information, social, and system function overload, might contribute to university students' mobile SNS fatigue and frustration, which may detrimentally impact their academic productivity. This theoretical framework is empirically validated through rigorous statistical analyses derived from a sample of 660 Chinese university students who frequently utilized mobile social media. The findings underscore that these three cognitive overload forms significantly predict mobile SNS fatigue and frustration, subsequently impairing university students' academic productivity. Moreover, the relationships between three cognitive overload types and academic productivity are mediated by mobile SNS fatigue and frustration. Consequently, this study advances the theoretical and empirical discourse on cognitive overload by applying the SOR model, elucidating the underlying mechanisms by which cognitive overload impacts university students' academic productivity. These insights deepen the scholarly understanding of the adverse consequences associated with mobile social media usage from a cognitive overload perspective, furnishing empirically grounded recommendations for multiple stakeholders to implement targeted interventions aimed at ameliorating these detrimental effects.publishe
Unique continuation of static overdetermined magnetohydrodynamic equations
No full textThis paper establishes the Unique Continuation Property (UCP) for a suitably overdetermined Magnetohydrodynamics (MHD) eigenvalue problem, which is equivalent to the Kalman, finite-rank, controllability condition for the finite-dimensional unstable projection of the linearized dynamic MHD problem. It is the “ignition key” to obtain uniform stabilization of the dynamic non-linear MHD system near an unstable equilibrium solution, by means of finitely many, interior, localized feedback controllers [Res. Math. Sci. 12 (2025), article no. 7]. The proof of the UCP result uses a pointwise Carleman-type estimate for the Laplacian following the approach that was introduced in [Nonlinear Anal. 71 (2009), 4967–4976] for the Navier–Stokes equations and further extended in [Appl. Math. Optim. 84 (2021), 2099–2146] for the Boussinesq system.publishe
MD-guided nucleation agent development for supercooling control in fatty alcohol PCM emulsions
No full textSupercooling in phase change dispersions significantly undermines the benefits of high latent heat storage capacity, especially those utilizing paraffin-based phase change materials (PCMs) because the delay in crystallization below the thermodynamic freezing point reduces both energy efficiency and system reliability due to the stochastic nature of nucleation. This work leverages Molecular Dynamics simulations with the OPLS force field to identify and design nucleation agents that mitigate supercooling by closely matching the structural and chemical characteristics of the PCM. Initial reference simulations over 100 ns of the PCM 1-docosanol showed crystallization onset at 320 K (47°C), 23 K below the bulk melting point, which was used to evaluate a range of candidate seed materials at 4–8 wt% loading, including higher-melting homologues and tailored ether-based dimers. The simulations revealed that optimal nucleation occurs when the seed offers a surface structurally analogous to the PCM’s molecular arrangement, promoting lateral crystalline growth and minimizing orientation barriers. Surfactant molecules with structurally compatible tail (e.g., C22 vs. C12) further reduced supercooling by 10 K. Subtle factors, such as consistent numbers of carbon atoms, were also found to influence crystallization behavior.
Experimental validation confirmed the simulation predictions, as a newly designed ether-based seed increased the onset crystallization temperature by additional 0.7 ± 0.1 K (≈10 %) compared to established nucleation additives. By guiding seed design through simulations, the approach lowers the need for extensive trial-and-error experiments, accelerating the development of improved nucleation additives. Overall, this study provides insights into the molecular mechanisms of PCM crystallization, offering a pathway to more efficient thermal energy storage systems through rational, simulation-informed material selection.publishe
Trapped between darkness and heat : desert birds (Argya squamiceps) initiate daily activity earlier (and terminate it later) in response to heat
No full textDiurnal desert endotherms must adjust the timing of their daily activity to mitigate physiological stress from ambient heat. Understanding the limits of this behavioural plasticity is important for predicting how climate change may affect desert species. Here, we studied the onset and termination of daily activity in wild birds (Arabian babblers Argya squamiceps) inhabiting the Arava Desert. We found that the birds (i) began/terminated their daily activity within a 45 min window around morning/evening civil twilights, (ii) advanced/delayed the onset/termination of daily activity in response to rising ambient heat, yet (iii) were never active in darkness. These temporal adjustments may help to mitigate energetic deficits caused by heat stress and concurrently extend foraging times under cooler temperatures. Though, subsequent analyses of the climate in the Arava Desert demonstrate (iv) a ~2°C increase in summer temperature over the past 31 years, and (v) that Arabian babblers advanced the onset of daily activity by 8.8 min during the last 11 summers. We thus propose the existence of a ‘heat versus dark trap’: rising temperatures drive diurnal desert endotherms to increase activity during the cooler pre-dawn and post-dusk times, but the leeway of these temporal adjustments is strictly constrained by nocturnal predation risk and reduced foraging efficiency in poor light conditions.publishe
How Perceived Motivations Influence User Stickiness and Sustainable Engagement with AI-Powered Chatbots : Unveiling the Pivotal Function of User Attitude
No full textArtificial intelligence (AI) is reshaping customer service, with AI-powered chatbots serving as a critical component in delivering continuous support across sales, marketing, and service domains, thereby enhancing operational efficiency. However, consumer engagement remains suboptimal, as many users favor human interaction due to concerns regarding chatbots’ ability to address complex issues and their perceived lack of empathy, which subsequently reduces satisfaction and sustainable usage. This study examines the determinants of user attitude and identifies factors influencing sustainable chatbot use. Utilizing survey data from 735 Chinese university students who have engaged with AI-powered chatbots, the analysis reveals that four key motivational categories: utilitarian (information acquisition), hedonic (enjoyment and time passing), technology (media appeal), and social (social presence and interaction) significantly influence user attitude toward chatbot services. Conversely, privacy invasion exerts a negative impact on user attitude, suggesting that while chatbots provide certain benefits, privacy issues can significantly undermine user satisfaction. Moreover, the findings suggest that user attitude serves as a pivotal determinant in fostering both user stickiness and sustainable usage of chatbot services. This study advances prior U&G-, TAM-, and ECM-based research by applying these frameworks to AI-powered chatbots in business communication, refining the U&G model with four specific motivations, integrating perceived privacy invasion to bridge gratification theory with risk perception, and directly linking user motivations to business outcomes such as attitude and stickiness. This study underscores that optimizing chatbot functionalities to enhance user gratification while mitigating privacy risks can substantially improve user satisfaction and stickiness, offering valuable implications for businesses aiming to enhance customer loyalty through AI-powered services.publishe