Search Results (616)

Can theology be considered a creative science? How can we define creativity in the work of the theologian? This article offers a meta-theological inquiry on the roles of creativity and tradition in innovating theological knowledge. After distinguishing between problem- and solution-driven creativity, I show that both theology and science require a living tradition to test, correct, and stabilize proposals over time. I introduce second-order cybernetics as a heuristic vocabulary through which to view observer-inclusive inquiry in theology. I analyze the main sources of theological novelty: inspiration, prophetic impulse, and charisms, whose discernment and reception shape the incorporation of novelty into Tradition. I argue that, likewise, in second-order cybernetics a system can maintain its identity by adapting to new issues, contexts, and forms of experience through negative and positive feedback mechanisms. These mechanisms preserve coherence in the system and allow for the diffusion and institutionalization of genuine novelty. Full article

Craving for mobile phone use is increasingly discussed as a relevant feature of problematic engagement with digital technologies. This population-based study of 1601 Spanish adults examined psychological factors (impulsivity traits and affective symptoms) and behavioral correlates linked to mobile phone craving. Primary outcome: Mobile phone craving scale (MPACS). Secondary analyses: Associations between craving and impulsivity, anxiety, depression, Internet Gaming Disorder (IGD), gambling severity, and alcohol use. Craving measured with the MPACS was most common among younger participants (16–35 years old) and strongly related to greater daily phone use, heightened impulsivity, especially urgency and sensation seeking, and higher levels of anxiety and depressive symptoms. Among individuals who use their phones for gaming or gambling (n = 463), craving was strongly associated with IGD and gambling severity, suggesting that mobile phones may amplify involvement in these behaviors. Exploratory factor analyses consistently revealed four underlying dimensions—Reactive Impulsivity, Cognitive Impulsivity, Negative Emotions, and Addictive Behaviors—each contributing differently depending on craving intensity. Logistic regression analyses showed that anxiety, impulsivity, phone-use duration, and IGD scores independently predicted high craving levels. Overall, the findings highlight mobile phone craving as a clinically meaningful, multidimensional construct tied to emotional dysregulation and behavioral addiction. Assessing craving may help identify individuals at heightened risk for problematic technology use and related psychological difficulties. Full article

Objective: The current study tested (1) how ADHD symptoms and internalizing or externalizing problems covaried across ages 3–18 in children with neurofibromatosis type 1 (NF1), and (2) whether demographic and NF1-specific factors moderated the associations. Method: We analyzed integrated cross-sectional data of 685 observations from 455 children and adolescents with NF1 (M_age = 9.79 years, SD = 3.88; 43% female) across six institutions in the United States and Australia. ADHD symptoms (inattention and hyperactivity/impulsivity) and internalizing/externalizing problems were assessed via parent-report measures. Time-varying effect modeling was employed to examine the age-specific associations between ADHD symptoms and internalizing/externalizing problems. Moderation analyses tested effects of sex, parental education, and NF1 inheritance mode (familial vs. sporadic). Results: Inattention and hyperactivity/impulsivity symptoms were associated with greater internalizing and externalizing problems across ages 3–17. Inattention links were similar across ages, while the hyperactivity/impulsivity-externalizing link was stronger in early childhood than during adolescence. NF1 inheritance mode significantly moderated the inattention-externalizing link, with stronger associations observed among children with familial NF1. Other moderators were nonsignificant. Conclusions: ADHD symptoms are robustly linked to internalizing and externalizing problems from childhood to middle adolescence in children with NF1, with familial NF1 emerging as a potentially elevated risk factor. Future longitudinal and experimental research is needed to inform integrated intervention approaches, especially for those with familial NF1. Full article

Polymathy relates to the exceptional learning abilities, in which individuals cultivate and coordinate Breadth, Depth, and integrative capability across multiple domains. It builds on mechanisms typically associated with intelligence, including abstraction, problem solving, and the transfer and integration of information. Because polymathic disposition has partial biological underpinnings, it may intersect with other biologically based individual differences, such as temperament. Biographical accounts also indicate that many polymaths did not achieve exceptional school grades, raising questions about whether the multiplicity of interests in polymaths is associated with distractibility and impulsivity, or whether there is a deeper institutional mismatch between polymaths and educational systems. Our study examined these issues using estimated high school grades across three subject areas, documented university grades, a neurochemistry-validated temperament assessment (Structure of Temperament Questionnaire; STQ-77), the Trait Polymathy Scale (TPS), the Barratt Impulsivity Scales (BIS-11), and information about aptitudes and interests from 296 participants (M/F = 152/144). Contrary to speculation that polymathy reflects distractibility, the TPS correlated negatively with the BIS-11 Lack of Attention scale and positively with the STQ-77 scales of Intellectual Endurance and Probabilistic Processing, confirming high sustained attention in polymaths. TPSs also had selective negative correlations with the STQ-77 Neuroticism scale and positive correlations with the STQ-77 Plasticity, Social Endurance, Sensation Seeking, dispositional Satisfaction scales, as well as several specific and general aptitudes and interests. These findings refine the dispositional profile linked to polymathy, highlighting the differential nature of the three components of polymathy. Full article

This paper studies mixed impulsive boundary value problems involving tempered $\mathsf{\Psi }$-fractional derivatives of Caputo type. By introducing exponential tempering into the fractional framework, the proposed model effectively captures systems with fading memory—an improvement over conventional power-law kernels that assume long-range dependence. The generalized tempered $\mathsf{\Psi }$-operator unifies several existing fractional derivatives, offering enhanced flexibility for modeling complex dynamical phenomena. Impulsive effects and integral boundary conditions are incorporated to describe processes subject to sudden changes and historical dependence. The problem is reformulated as a Volterra integral equation, and fixed-point theory is employed to establish analytical results. Existence and uniqueness of solutions are proven using the Banach Contraction Mapping Principle, while the Leray–Schauder nonlinear alternative ensures existence in non-contractive cases. The proposed framework provides a rigorous analytical basis for modeling phenomena characterized by both fading memory and sudden perturbations, with potential applications in physics, control theory, population dynamics, and epidemiology. A numerical example is presented to illustrate the validity and applicability of the main theoretical results. Full article

To address the stringent insulation safety requirements of modern high-voltage transformers, accurately characterizing the transient electric field is critical. However, a significant problem remains: current engineering models typically rely on static capacitive distributions, failing to capture the dynamic electric field distortion induced by rapid space charge injection under lightning impulses. Therefore, a non-contact spatial electric field measurement method based on the optical Kerr effect was employed to analyze the influence of electrode material, voltage amplitude, and wavefront time. Unlike traditional simulation models that often assume constant mobility and focus solely on the shielding effect, this study reveals a non-monotonic electric field evolution driven by a ‘Static-Dynamic’ mode transition. The proposed model highlights two critical breakthroughs: (1) Mechanism Innovation: It experimentally verifies that charge injection is governed by the ion charge-to-mass ratio rather than just the work function, leading to a newly identified field enhancement phase during the wavefront that overcomes the limitations of capacitive models that underestimate transient stress. (2) Parameter Quantification: Precise spatiotemporal thresholds are established—negative charges traverse the gap within ~200 ns, while positive charges require ~10 μs to reach equilibrium. These findings provide experimentally calibrated time constants for simulation correction and offer new criteria for optimizing electrode materials in UHV transformers to mitigate transient field distortion. Full article

Background: Non-suicidal self-injury (NSSI) is defined as the intentional damage to one’s body tissue without suicidal intent and for reasons that are not socially sanctioned. While NSSI has been widely studied in the general population, its clinical correlates and management in autism spectrum disorder (ASD) remain less clearly characterized, and it is often conflated with self-injurious behavior (SIB) described within restricted and repetitive behaviors (RRBs). In individuals with ASD, NSSI may be associated with emotional, behavioral, cognitive, social, medical, and demographic factors, and it differs from SIB typically observed among individuals with severe intellectual disabilities. Methods: A systematic review was conducted in accordance with PRISMA guidelines. Studies published between 2000 and 2025 that assessed NSSI in individuals with a formal ASD diagnosis were included. Etiological/clinical correlates, explanatory mechanisms, and management challenges were examined. Sixteen studies were selected from PubMed, Scopus, and Web of Science. Findings were synthesized using narrative and thematic approaches. Results: The prevalence of NSSI among individuals with ASD ranged from 24% to 50%. Associated factors included emotion dysregulation (including alexithymia and affective distress), behavioral dysregulation (e.g., impulsivity/hyperactivity and aggression), sensory processing difficulties, communication and social impairments, and medical comorbidities (i.e., gastrointestinal and sleep problems), with preliminary evidence also implicating perinatal factors. NSSI was linked to emotion regulation, sensation seeking, and social communication processes. Early intervention and parental involvement were identified as protective factors. Conclusions: NSSI in ASD is a complex, multifactorial phenomenon frequently linked to emotion-regulation needs. Affective imbalance represents a central—though not exclusive—pathway. The review supports standardized terminology, function-based assessment, and clearer differentiation from SIB/RRBs, with implications for individualized interventions and sustained monitoring in persistent or severe cases. Routine screening for medical and sensory contributors may further improve case management and reduce preventable clinical burden. Full article

This paper presents a comparative study of the applicability and accuracy of optimal control methods and neural-network-based estimators in the context of porkchop plots for preliminary asteroid rendezvous mission design. The scenario considered involves a deep-space CubeSat equipped with a low-thrust engine, departing from Earth and rendezvousing with a near-Earth asteroid within a three-year launch window. A low-thrust trajectory optimization model is formulated, incorporating variable specific impulse, maximum thrust, and path constraints. The optimal control problem is efficiently solved using Sequential Convex Programming (SCP) combined with a solution continuation strategy. The neural network framework consists of two models: one predicts the minimum fuel consumption ($\Delta v$), while the other estimates the minimum flight time ($\Delta t$) which is used to assess transfer feasibility. Case results demonstrate that, in simplified scenarios without path constraints, the neural network approach achieves low relative errors across most of the design space and successfully captures the main structural features of the porkchop plots. In cases where the SCP-based continuation method fails due to the presence of multiple local optima, the neural network still provides smooth and globally consistent predictions, significantly improving the efficiency of early-stage asteroid candidate screening. However, the deformation of the feasible region caused by path constraints leads to noticeable discrepancies in certain boundary regions, thereby limiting the applicability of the network in detailed mission design phases. Overall, the integration of neural networks with porkchop plot analysis offers an effective decision-making tool for mission designers and planetary scientists, with significant potential for engineering applications. Full article

This paper investigates the equivalent integral equations (EIEs) of two impulsive right-sided Riemann–Liouville fractional-order systems (IRRFOSs). The limit properties of one IRRFOS are employed to establish the linear additivity of impulsive effects. A computational approach based on fractional calculus for piecewise functions is then employed to construct the EIE corresponding to a single impulse. With the aid of this linear additivity, the EIE of the considered IRRFOS is obtained, and through the relationship between the two IRRFOSs, the EIE of the other IRRFOS is further derived. The results indicate that the solutions of both EIEs consist of linear combinations of $\varphi \left(t\right)$ and ${\mathrm{\Phi }}_j\left(t\right)$$(j=1,2,\dots ,N)$ containing an arbitrary constant, which implies the non-uniqueness of solutions to the two IRRFOSs. Finally, the computational procedure for deriving the EIEs of the two IRRFOSs is presented, and the non-uniqueness of solutions is illustrated through two numerical examples. Full article

With the development of heavy-haul trains towards long formation and large axle load, the longitudinal impulse problem of trains is aggravated not only by improving the transport capacity of railway freight cars, but also by the braking characteristics such as the asymmetry in brake release, which has a greater impact on the longitudinal impulse of trains, seriously affecting the operation safety of trains. In this paper, a 20,000-ton heavy-haul train is taken as the research object, a train air brake system model is established by the parallel method, and the train longitudinal dynamics model is co-simulated to study the influence of braking characteristics on the longitudinal force of the train. The results indicate that the train is primarily subjected to compressive coupler forces during braking, with the maximum compressive force occurring at car 109. Compared to the maximum compressive coupler force observed under a 50 kPa reduction in brake pipe pressure, the maximum forces under 70 kPa and 100 kPa reductions increased by 16.8% and 36.8%, respectively. The controllable tail system influences the braking of middle and rear cars by supplying a braking source to the last car. When the delay time of the controllable tail system is set to 3 s, braking synchronization can be improved. Furthermore, compared to scenarios without last-car charging, the installation of a last-car charging device reduces the maximum tensile coupler force from 780 kN to 489 kN, representing a 37% decrease. The findings of this study provide theoretical insights for ensuring the safe operation of heavy-haul trains and contribute to enhancing their operational performance. Full article

The problem of identifying non-stationary communication channels with a sparseness property using the local basis function approach is considered. This sparseness refers to scenarios where a few impulse response coefficients significantly differ from zero. The sparsity-aware estimation algorithms are usually obtained using ${\mathit{\ell }}^1$ regularization. Unfortunately, the minimization problem lacks a sometimes closed-form solution; one must rely on numerical search, which is a serious drawback. We propose the fast regularized local basis functions (fRLBF) algorithm based on appropriately reweighted ${\mathit{\ell }}^2$ regularizers, which can be regarded as a first-order approximation of the ${\mathit{\ell }}^1$ approach. The proposed solution incorporates two regularizers, enhancing sparseness in both the time/lag and frequency domains. The choice of regularization gains is an important part of regularized estimation. To address this, three approaches are proposed and compared to solve this problem: empirical Bayes, decentralized, and cross-validation approaches. The performance of the proposed algorithm is demonstrated in a numerical experiment simulating underwater acoustics communication scenarios. It is shown that the new approach can outperform the classical one and is computationally attractive. Full article

Background/Objectives: Children with hearing loss (HL) could experience significant fatigue which compromises their performance. The effort related to the combination of HL and visual impairment in children affected by Usher syndrome (USH) could compromise mental health, socio-emotional behavior and academic achievement. The aim of the present study was to analyse the listening effort in USH cases types 1 and 2 and its relation to age, molecular diagnosis, visual field, visual acuity, degree of HL, vestibular impairment and spatial orientation. Methods: This was a retrospective monocentric study. Twenty children with genetically confirmed USH (USH2 in 15/20–75% and USH1 in 5/20–25%), age range 3–17 years (mean 9.6 ± 4.7), underwent: the Vanderbilt fatigue scale questionnaire (VFS), audiological and vestibular assessment including the Oldenburg Matrix test in Italian and video head impulse test (VHIT), sound localization test and ophthalmologic examination. Results: We observed a more pronounced HL and deteriorated vestibular function in those with USH1. They also employed significantly more time and head movements to localize sounds compared to USH2 and had the worst visual field on eye examination. The VFS did not show significant differences between the two groups, with the exception of the physical fatigue reported by parents. Mean VFS was linearly related to age, the hearing threshold of the worse ear, data logging hours of hearing device, time and head movements of the localization test, VHIT asymmetry and balance problems referred by parents and the visual field. USH type 1 had no greater risk of fatigue than USH2. Profound hearing loss, data logging of hearing device < 8 h a day, difficult localization test, balance problems and low retinal sensitivity represented risk factors for listening effort measured with VFS. Conclusions: Listening effort in difficult environments such as school rooms in USH patients is not only associated to hearing function but also to the spatial awareness determined in part by vestibular and visual function. Teachers should be informed and made aware of multiple comorbidities in order to facilitate learning. Full article

In this paper, we investigate the optimal control problem regarding a class of dynamic systems, aiming to address the challenge of simultaneously ensuring cost minimization and system asymptotic stability. The theoretical framework proposed in this paper integrates the value function concept from optimal control theory with Lyapunov stability theory. By setting the impulse cost at any finite time to be strictly positive, we exclude Zeno behavior, and a set of sufficient conditions is established that simultaneously guarantees system asymptotic stability and cost minimization based on Quasi-Variational Inequalities (QVIs). To address the challenge of solving the Hamilton–Jacobi–Bellman (HJB) equation in high-dimensional nonlinear systems, we employ an inverse optimal control framework to synthesize the strategy and its corresponding cost function. Finally, we validate the feasibility of our method by applying the theoretical results obtained to three numerical examples. Full article

The paper presents the results of numerical simulation of the dynamic behaviour of the post-tensioned beams subjected to a constant force impulse load over time and a short-term force impulse load varying over time. Abaqus programme was used for numerical analysis, introducing necessary and detailed modifications to the modelling and calibration parameters. The numerical dynamics models were calibrated using results previously obtained from our own experimental and numerical static analysis. To estimate the dynamic strength of structural materials, the dynamic strength coefficient was applied in the concrete damage plasticity model, and the Johnson–Cook model was used to describe the evolution of the dynamic yield strength of steel elements. An explicit procedure was used to solve the dynamic equilibrium equations. The selection of the Rayleigh damping parameter and the methodology for determining the external load in a dynamic problem are discussed. The study presents new results on the influence of the type of force impulse loading and variable prestressing eccentricity in numerical simulations of post-tensioned beams. The results of the simulation show that the post-tensioned beams achieved a lower dynamic load capacity under a constant force impulse load of approximately 5% compared to the static load capacity achieved in the experimental static tests, regardless of the assumed prestressing eccentricity. A dynamic load capacity significantly exceeded the static load capacity under short-term time-varying force impulse loading. The beam with the larger prestressing eccentricity achieved a dynamic load capacity of 211% of the static load capacity, while the beam with the smaller prestressing eccentricity achieved a dynamic load capacity of 198% of the static load capacity. Full article

We establish the existence and uniqueness of solutions to a class of second-order nonlinear boundary value problems involving impulses, delay, and possible singularities. The approach leverages the recent notion of paired-Chatterjea-type contractions. Under a smallness condition ensuring the associated integral operator is a Banach contraction with constant $\mu <{\displaystyle \frac{1}{3}}$, we show that it is also a Chatterjea, and hence, a paired-Chatterjea contraction. By the fixed point theorem of Chand, this guarantees at most two fixed points; a supplementary uniqueness argument then ensures a unique solution in the Banach space $P{C}^1\left([a,b]\right)$. Full article