Search Results (4,212)

Recent scientific evidence confirms that there is no safe threshold for bisphenol A intake, prompting strict regulatory actions and new prohibitions in the European Union. As a result, bisphenol A has increasingly been replaced by other analogues that are also toxic but less regulated and insufficiently studied, posing a new risk to human health due to cumulative exposure. Since food is the primary source of exposure to these compounds, this review aimed to evaluate the most appropriate existing chromatographic methods for their determination under newly introduced near-zero tolerance limits, as well as to assess current cumulative dietary exposure and associated health risks. A systematic literature search was conducted in major scientific databases and relevant regulatory sources covering the period from 2015 to 2025, following PRISMA guidelines. Of the 489 identified publications, 22 met the eligibility criteria for full-text analysis. The findings indicate a clear methodological shift towards simultaneous quantification of multiple bisphenol analogues, with LC-MS/MS emerging as the dominant and most robust analytical technique. Dietary exposure to bisphenol A is expected to decline due to stricter regulations; however, this may trigger a rise in the use of its structural analogues as alternatives. Exposure assessments indicate that combined dietary intake of bisphenol A and its analogues can result in a Hazard Index exceeding 1, primarily due to the substantially reduced Tolerable Daily Intake for bisphenol A. This highlights the need for continuous monitoring under stricter regulatory frameworks. Full article

This study presents an optimization tool inspired by bone remodeling principles to address the high computational costs of truss topology optimization. Additionally, a new structural analysis method based on primary forces is proposed to overcome the kinematic stability problem. The strategy developed to obtain the optimal topology optimizes the initial dense ground structure in two stages. In Phase I, unnecessary members in the system are filtered to determine the “primary candidate members”; in Phase II, the final topology is reached through this refined subset. The algorithm performs an effective search in the design space by simulating biological processes that link the rate of mass change in the bone matrix to mechanical stimuli. Numerical results demonstrate high accuracy, as shown by the analytical solution of the 2D Michell truss, with a difference of 1.02%. The results show high consistency with reference studies, providing, in some cases, alternative topologies with the same weight and stiffness as given in the benchmarks. The proposed method achieves significant improvements in computational efficiency, reducing processing times for larger systems by 10 to over 250 times compared to literature benchmarks. Full article

The highly competitive nature of the online food delivery (OFD) market faces a serious retention problem, with acquiring new users typically being much more expensive than retaining existing users. Traditional prediction methods that rely primarily upon static transactional metrics such as recency and frequency are often unable to capture the psychological ‘disconfirmation’ which occurs prior to churn. To fill this gap, this study proposes a framework based on Expectation-Confirmation Theory (ECT). Unsupervised K-Means clustering was employed to classify a simulated and filtered dataset with 1500 customer records containing behaviour, geography, etc. This framework also couples sentiment analysis from BERT, allowing it to identify psychological “silent” attrition. Heterogeneous cohorts, which exhibit different psychological antecedents (utilitarian versus hedonic), were identified. The empirical results of our analyses demonstrated that Random Forest Classifiers with segment-specific features outperform baseline transactional models (F1 = 0.76) with an F1 Score of 0.89. The visual analytic interface developed provides a holistic view of the consumption process than traditional prediction models, including prescriptive, automated segment-based mitigation strategies. Our findings contradict the assumption that the “frequency–loyalty” model applies to all users. High-frequency discretionary users are found to be elastic in terms of retention and will experience significant churn. By utilising the automated action log, managers can plan targeted, highly efficient retention strategies rather than blanket discounting approaches. Full article

This study is a detailed study of unit J-shaped distributions which establishes and examines the unit Topp–Leone distribution. The proposed study presents a mathematically tractable model of bounded data with strong skewness and boundary effects. Various basic distributional properties, such as moments, entropy measures, order statistics, and L-moments, are obtained in explicit form, which provides a full analytic description of the model. Type-II censoring is applied to develop some statistical inferential methods. The usefulness of the suggested distribution is illustrated by the application to the normalized water use efficiency indicators and censored survival time data. The findings are useful to the theory of unit distributions, as they introduce new analytics that have been demonstrated to be beneficial in practice and demonstrate that the theory is effective in applications with limited and censored data. Full article

This work presents a space-oriented extension of an existing research program focused on developing innovative approaches and design solutions for rotorcraft. The study builds upon recent research conducted at the Military University of Technology, where new methods for main rotor optimization using parametric modeling were developed. The primary objective of this research is to investigate the feasibility of designing a rotorcraft capable of operating in the Martian environment. The proposed vehicle is intended to perform vertical takeoff, flight, and landing; sustain at least two hours of continuous operation; and transport a pilot with either a passenger or an equivalent payload of 100 kg. Additionally, the rotorcraft should be capable of being restored to an airworthy condition after each mission and prepared for reuse while maintaining its operational capabilities. Preliminary performance analyses were conducted based on Martian atmospheric conditions. Analytical models implemented in dedicated computational tools were used to estimate rotor dimensions, performance, and trim requirements. Several rotor configurations were evaluated to assess the feasibility of manned flight with an additional payload under extraterrestrial conditions. The results identify key limitations, risks, and technological challenges, while also highlighting potential design opportunities. The study culminates in a conceptual design proposal for a future Martian rotorcraft mission. The findings demonstrate the applicability of the proposed methodology and provide a foundation for further research and development in planetary rotorcraft systems. Full article

To varying degrees, optimization is a widely accepted procedure in the design of electrical machines, especially induction machines. This is associated with stringent requirements stemming from international regulations. The use of induction machines in new solutions, including low-speed vehicle drives, introduces challenges because they require high electromagnetic torque at low speeds. These requirements, including dimensional constraints, mean that despite sophisticated optimization, the classic design does not achieve the desired results. In such a case, a general redesign of the motor is necessary, replacing the classic internal rotor motor with an external rotor motor. This paper presents an example of such a design change as part of the parameter refinement process for two selected high-power, high-pole induction motors. Both the FEM method and a suitably adapted analytical method were used to investigate the impact of the design change. This enabled verification of the analytical method’s accuracy and rapid modeling of phenomena and parameters in external rotor motors. The proposed approach can be used to design novel structures and select motor controls for various applications. Full article

Scientific evidence is fundamental to uncovering insights about health, including food and nutritional claims. Substantiating such claims requires robust scientific procedures that often include clinical studies, biochemical analyses, and the examination of multiple forms of data. The growing capabilities of artificial intelligence (AI) and large language models (LLMs) present new opportunities for analyzing food–health relationships and supporting health claim validation. Yet, applying these technologies to the food and nutrition domain raises challenges that differ from those encountered in broader biomedical text mining (TM). In this perspective, we review key issues, including the complexity and heterogeneity of food-related data, the scarcity of food-specific language models and standardized resources, difficulties in interpreting nuanced and often contradictory evidence, and requirements for integrating AI tools into regulatory workflows. We compare modern LLM approaches with traditional TM methods and discuss how each may complement the other. Our position is that, despite their promise, current AI and LLM tools cannot yet reliably handle the subtleties of food–health evidence without substantial domain-specific refinement and human expert oversight. We advocate for hybrid approaches that combine the precision of established TM techniques with the analytical breadth of LLMs, supported by harmonized ontologies, multidimensional evaluation frameworks, and human-in-the-loop validation, particularly in regulatory contexts. We also highlight the importance of public education, transparent communication standards, and coordinated cross-disciplinary efforts to ensure these technologies serve broader goals of food safety, consumer trust, and global health. Full article

Following the transfer of farmland, new agricultural entities exhibit clearer profit-oriented goals and heightened sensitivity to changes in profitability. Changes in farmland transfer prices significantly affect producers’ crop selection, input choices, technology adoption, farming methods, and intensity. This study establishes a motivation–behavior–outcome analytical framework by integrating producer behavior theory with the mechanism of farmland health formation, suggesting that rising transfer prices may prompt producers to exhibit five types of positive or negative behaviors. The SBM-DEA model is employed to measure the grain green total factor productivity of farmland across 102 counties in China’s Henan Province from 2017 to 2022, reflecting the healthy utilization of farmland. Results from the two-way fixed-effects and threshold effect models reveal an inverted U-shaped relationship, indicating initially positive and later negative impacts of increasing transfer prices on farmland health utilization. GTWR model findings highlight that economic disparities and the pace of price increases dictate the intensity of producers’ positive and negative motivations, while the economic capacity for absorbing shocks and the natural endowment capacity for absorbing shocks influence the likelihood and magnitude of these effects. Government regulation should, therefore, focus on regulating producer interests. Full article

This study investigates amplified hydraulic braking systems employed in high-performance motorsport applications, utilizing wedge mechanisms for self-energization. An analytical expression for the gain coefficient is derived from a simplified equilibrium analysis of the wedge-shaped pad, capturing the nonlinear dependency on both wedge angle and effective mean disc-pad friction. A previously validated coupled thermoelastic model for carbon-carbon (C/C) braking systems—developed in Dymola and Modelica using the finite volume method (FVM) and an analytical local friction formulation—is here adapted to wedge-amplified braking systems, with the aim of providing performance assessment during the design phase of new calipers at reduced computational cost compared to coupled thermoelastic finite element method (FEM) models. Several caliper configurations featuring different wedge angles are tested experimentally on a dynamometer. A reduction in the effective friction coefficient at high mean effective contact pressure—induced by pronounced wedge angles and reduced pad areas—is observed. To validate the thermoelastic model, simulated braking torque and disc surface temperature are compared against bench data. The model shows satisfactory predictive capability under various operating conditions and test cycles, with mean error indices on peak torque prediction below $5\%$ for the majority of the simulated cases. Finally, the validated model is used to virtually assess the performance of a new caliper prototype prior to its manufacturing and testing. Full article

Melatonin, an indoleamine crucial for regulating circadian rhythms, sleep–wake cycles, and immune–endocrine homeostasis, is present in biological fluids at extremely low concentrations, making its quantification analytically challenging. This narrative review provides a critical comparative assessment of current methodologies for melatonin determination across various biological matrices—plasma, urine, saliva, breast milk, and hair. The discussed techniques include immunoassays, colorimetric and spectrophotometric methods, chromatographic–mass spectrometric platforms (LC–MS/MS, UHPLC–MS/MS), and emerging biosensors. Each approach is evaluated regarding analytical sensitivity, specificity, reproducibility, cost, and clinical applicability. While immunoenzymatic and colorimetric techniques offer accessible, low-cost solutions for large-scale or preliminary studies, LC–MS/MS remains the benchmark for reference analysis, providing sub-picogram detection limits and multiplexing capability. However, its high cost, procedural complexity, and inter-laboratory variability limit routine implementation. New developments, including molecularly imprinted polymers, dispersive microextraction, and nanomaterial-based biosensors, suggest a shift toward hybrid, sustainable, and portable analytical platforms. By synthesizing recent methodological advances and identifying key limitations, this review aims to guide researchers and clinicians in selecting the most appropriate analytical approach for clinical, pharmacological, and circadian biomonitoring applications. Full article

The reliable operation of transmission lines is essential for grid stability. Growing electricity demand pushes existing lines to full capacity, while new construction is constrained by resources and the environment. Dynamic capacity increase technology addresses this by boosting transmission capacity without physical upgrades, with the identification of weak points along the line being central to its application. This study integrates correlation analysis and the Analytic Hierarchy Process to develop an evaluation method for transmission line segments, with a supporting software implementation also developed. A system of characteristic quantities was first established using operation and maintenance guidelines combined with correlation analysis. The Analytic Hierarchy Process was applied to score features and derive weights after consistency validation. Preprocessed line data were then weighted to calculate segment weakness levels, and fuzzy comprehensive evaluation was used for both qualitative and quantitative condition analysis. The model was validated through a case study, and its software implementation streamlines and enhances the assessment process. Full article

Compensation for mental distress in preschool children is a crucial mechanism for protecting their personality rights, yet current judicial practice in China relies heavily on judicial discretion and lacks child-sensitive standards for determining severity. Following the enactment of the Preschool Education Law of the People’s Republic of China in 2025, the principle of the Best Interests of the Child has placed new behavioral and developmental requirements on decision-making, particularly regarding the recognition of children’s expressive limitations and psychological vulnerability. Drawing on representative judicial cases, this research identifies inconsistencies in current adjudication—primarily between factual presumption and medical proof—and highlights their failure to reflect preschoolers’ developmental characteristics. To address this gap, we construct a child-centered liability determination framework integrating the Lundy model of child participation and Nussbaum’s Capabilities Approach. This framework provides a structured method for incorporating children’s voices into proceedings and offers multidimensional criteria for assessing capability impairment as an indicator of mental distress severity. These findings suggest that the framework can help reduce excessive discretion, strengthen developmental sensitivity, and promote more consistent and equitable adjudication. Beyond the Chinese context, this research offers an analytical lens for advancing international discussions on child-centered mental distress assessment and children’s rights protection. Full article

Compared with previous analytical designs for deep UBHE, the present study is new in three aspects: (1) a segmented FLS model combined with the virtual heat source method is applied to the full U-shaped path (injection, horizontal, and production wells) in a unified formulation; (2) equivalent thermal conductivity is introduced to account for groundwater seepage in porous media, avoiding the need for separate CFD or coupled numerical solvers; (3) the relationship between production well depth and the maximum effective insulation length is quantified and discussed. Deep U-shaped borehole heat-exchangers (UBHE) systems boast high heat-exchange efficiency, yet most analytical models are too simplistic, causing inaccuracies. This study proposes a segmented finite line source (FLS) model for UBHE using the virtual heat source method. Introducing equivalent thermal conductivity (k_equ), it treats rock-soil as a groundwater-saturated porous medium, coupling seepage’s dynamic heat-transfer impact. By comparing the simulation results of the same type of research within 720 h, the average temperature difference between the models was found to be 1.31 °C, with an error rate of 5.31%, which is 40.87 percentage points lower than the existing achievements, thereby demonstrating the accuracy of this model. In addition, based on this model, the influence trends of five main factors such as seepage velocity and geothermal gradient on the system’s heat exchange were drawn and analyzed. Among them, the laying length of the insulation layer was analyzed in detail. The results show that its maximum laying length should be in line with the depth node where reverse heat exchange occurs with the production well. Under the set conditions of this study, when the depth of the production well is 2500 m, the maximum laying length of the insulation layer is 1900 m. Full article

Food safety, quality, and traceability have become increasingly important in the agrifood industry in recent years, necessitating the use of reliable and rigorous analytical tools to ensure agrifood surveillance. This work focuses on the development and application of a new molecular approach to verify the authenticity of a specific variety of Triticum turgidum ssp. turanicum, commonly known as Khorasan wheat, which is commercially sold under the KAMUT^® trademark. A method based on duplex digital PCR was developed to identify and quantify T. turanicum variety QK-77 used in KAMUT^® brand products. The assay was validated on pure QK-77 variety alone and mixed with other varieties and on other cereal species. The developed PCR-based assay, tested using two digital PCR platforms (cdPCR and pdPCR), has high sensitivity and accuracy and can be applied to quantify the QK-77 variety in commercial grain lots and processed foods. Full article

Safe Beyond Visual Line of Sight (BVLOS) operations are increasingly required for wildlife monitoring and conservation, yet existing regulatory frameworks are rarely tailored to protected areas characterised by low population density and limited infrastructure. This paper presents a field-based use case illustrating how the Specific Operations Risk Assessment (SORA) methodology can be applied to conservation-oriented BVLOS missions under Kenyan airspace conditions, including coordination within military-controlled airspace. We evaluate three population-density estimation approaches (qualitative, bottom-up, and top-down) against available ground truth, and compare tabulated and analytical SORA methods for deriving the Ground Risk Class. The work illustrates how SORA 2.5 structures ground and air risk reasoning in a conservation context, while retrospective review identifies limitations in containment, Operational Safety Objectives, and tactical mitigation performance requirements. Field trials involved five concurrent teams and 30 personnel conducting over 260 flights and more than 60 h of UAS activity across the Ol Pejeta Conservancy, providing insights into multi-team coordination under field conditions. Field implementation revealed areas of misalignment between prescribed safety requirements and operational realities, prompting iterative adaptation of workflows and procedures. Observed outcomes included reductions in team size (25–50%) and procedural steps (18%), derived from retrospective comparison of field procedures. A lightweight Uncrewed Traffic Management prototype was also trialled, revealing practical limitations in conservancy environments. Finally, we present a ten-step framework for developing field-ready safety procedures to support risk-informed decision-making in non-standard operational contexts. The findings provide empirically grounded guidance on applying SORA principles to conservation UAS missions, without proposing a new risk framework or generalised operational model. Full article