Search Results (10,488)

Conventional machines often face limitations due to complex controllers and bulky power supplies, which can hinder their reliability and operability. In contrast, self-excited movements can harness energy from a stable environment for self-regulation. In this study, we present a novel model of a self-rowing boat inspired by paddle boats. This boat is powered by a liquid crystal elastomer (LCE) turntable that acts as a motor and operates under consistent illumination. We investigated the dynamic behavior of the self-rowing boat under uniform illumination by integrating the photothermal reaction theory of LCEs with a nonlinear dynamic framework. The primary equations were solved using the fourth-order Runge–Kutta method. Our findings reveal that the model exhibits two modes of motion under steady illumination: a static pattern and a self-rowing pattern. The transition between these modes is influenced by the interaction of the driving and friction torques generated by photothermal energy. This study quantitatively analyzes the fundamental conditions necessary for initiating a self-rowing motion and examines how various dimensionless parameters affect the speed of the self-rowing system. The proposed system offers several unique advantages, including a simple structure, easy control, and independence from electronic components. Furthermore, it has the potential for miniaturization and integration, enhancing its applicability in miniature machines and systems. Full article

Background: Cigar smoking poses significant public health challenges due to its rising prevalence and associated health risks. However, research on cigar use in China remains limited. This study investigates the prevalence, demographic characteristics, and key factors associated with cigar use among Chinese adults. Methods: We analyzed data from the 2018–2019 China Health Literacy Survey, including 86,701 participants aged 20–69 years. Multistage stratified sampling was employed, and logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with cigar use. Weighted data were applied to ensure national representation. Results: Of the 86,701 respondents, 1025 participants reported having used cigars, including 248 exclusive cigar users and 777 dual users of cigars and other tobacco products. Cigar use was significantly higher among men (1.93%) than women (0.05%). Most users were aged 50–59, with a mean age of 49.3 years. Factors associated with cigar use among men included higher education (for college and higher, OR: 1.81; 95% CI: 1.42–2.30), lower household income (for income < 20,000, OR: 1.02; 95% CI: 1.08–1.53), poor self-reported health (OR: 1.45; 95% CI: 1.15–1.83), and severe nicotine dependence (FTND ≥ 7 points, OR: 2.09, 95% CI: 1.67–2.61). Cigar use prevalence showed notable regional variation, with the highest rates observed in northern and eastern provinces. Interpretation: The estimated number of cigar users in China is approximately 10.46 million. Male cigar users often represent a unique demographic: “knowledgeable but economically marginalized” individuals, characterized by higher education but lower economic status. Tailored tobacco control measures addressing regional disparities, socioeconomic factors, and marketing-driven misconceptions about cigars are essential to reduce public health impacts. Full article

Background and Objectives: Obesity in youth is a growing public health concern, placing them at higher risk for adverse physical and psychological outcomes. Understanding the predictors that affect weight management, particularly the role of internalized weight stigma, psychosocial factors, and eating behaviors, is essential for developing an effective intervention at longitudinal follow-up. Materials and Methods: We enrolled 102 youths with obesity aged 10 to 18 years old from clinical settings. Baseline demographic data, psychosocial measures, including the Weight Self-Stigma Questionnaire (WSSQ) and Hospital Anxiety and Depression Scale (HADS), and eating behavior scales, such as the Three-Factor Eating Questionnaire (TFEQ-R21) and eating disorder as Sick, Control, One, Fat, Food questionnaire (SCOFF), were collected in the first visit. We conducted a study with both cross-sectional and longitudinal components. Correlational bivariate analysis was conducted to explore relationships between key variables. The factors affecting BMI changes were investigated using generalized estimating equations (GEEs) as part of a longitudinal analysis. Results: The mean age of participants was 13.22 years and 63.7% were male. Bivariate correlation analysis revealed positive relationships between initial BMI Z-scores and WSSQ scores (r = 0.196, p < 0.05). In bivariate analysis, a negative correlation was found between the difference in BMI Z-scores and visit number (r = −0.428, p < 0.01). GEE analysis demonstrated that initial BMI Z-scores (coefficient = 1.342, p < 0.001) and anxiety (coefficient = 0.050, p < 0.001) were significant positive predictors of BMI Z-scores, while depression was negatively associated (coefficient = −0.081, p < 0.001). Excluding the TFEQ subscales, SCOFF improved the model’s QIC and highlighted WSSQ as a significant, albeit weak, predictor (p = 0.615 in the full model versus p < 0.05 in the reduced model). Conclusions: Psychosocial factors, particularly anxiety and weight stigma, are associated with elevated BMI Z-scores in youth affected by obesity in this study. The baseline age, BMI Z-score, internalized weight stigma, and psychological stress influenced the body weight trajectory over time. Frequent clinical follow-ups contribute to improved BMI outcomes. Future research may examine the efficacy of weight management by reducing weight stigma and psychological distress along with the outpatient care of obesity. Full article

Background: Multiple daily injections (MDIs) have been a mainstay for insulin delivery by persons with type 1 diabetes mellitus (T1DM). “Smart” insulin pens (SIPs) offer several advantages over traditional insulin pens, such as a memory function, bolus calculator, and reminders for patients to take their insulin. SIPs can integrate with CGM, allowing for the collection of accurate insulin and glucose data, which can integrate into combined reports. Using these technologies along with telecommunication modalities provides an infrastructure to improve the way in which healthcare can be delivered to those with diabetes. Methods: Four cases of uncontrolled T1DM managed by MDIs (and not insulin pumps) and deemed to have plateaued in their management were selected to retrospectively review to identify potential advantages of SIP/CGM along with telemedicine as a method of care delivery. Results: This case series revealed potential benefits of this model of care delivery, such as the ability to identify dysglycemia patterns not discernible prior to the use of SIP/CGM, use combined reports as a visual education tool to provide targeted insulin and dietary education, and improve patient engagement in diabetes self-care behaviors. Conclusions: We described the benefits of using SIPs and CGM technologies along with telecommunication solutions, as a novel concept for a comprehensive telemedicine system, to improve management of glycemic control and diabetes self-management capabilities. Full article

The Hengduan Mountains region (HMR) is vulnerable to flash flood disasters, which account for the largest proportion of flood-related fatalities in China. Flash flood regionalization, which divides a region into homogeneous subdivisions based on flash flood-inducing factors, provides insights for the spatial distribution patterns of flash flood risk, especially in ungauged areas. However, existing methods for flash flood regionalization have not fully reflected the spatial topology structure of the inputted geographical data. To address this issue, this study proposed a novel framework combining a state-of-the-art unsupervised Graph Neural Network (GNN) method, Dink-Net, and Shapley Additive exPlanations (SHAP) for flash flood regionalization in the HMR. A comprehensive dataset of flash flood inducing factors was first established, covering geomorphology, climate, meteorology, hydrology, and surface conditions. The performances of two classic machine learning methods (K-means and Self-organizing feature map) and three GNN methods (Deep Graph Infomax (DGI), Deep Modularity Networks (DMoN), and Dilation shrink Network (Dink-Net)) were compared for flash-flood regionalization, and the Dink-Net model outperformed the others. The SHAP model was then applied to quantify the impact of all the inducing factors on the regionalization results by Dink-Net. The newly developed framework captured the spatial interactions of the inducing factors and characterized the spatial distribution patterns of the factors. The unsupervised Dink-Net model allowed the framework to be independent from historical flash flood data, which would facilitate its application in ungauged mountainous areas. The impact analysis highlights the significant positive influence of extreme rainfall on flash floods across the entire HMR. The pronounced positive impact of soil moisture and saturated hydraulic conductivity in the areas with a concentration of historical flash flood events, together with the positive impact of topography (elevation) in the transition zone from the Qinghai–Tibet Plateau to the Sichuan Basin, have also been revealed. The results of this study provide technical support and a scientific basis for flood control and disaster reduction measures in mountain areas according to local inducing conditions. Full article

Background/Objectives: The widespread phenomenon of “brain rot”, named the Oxford Word of the Year 2024, refers to the cognitive decline and mental exhaustion experienced by individuals, particularly adolescents and young adults, due to excessive exposure to low-quality online materials, especially on social media. The present study is exploratory and interpretative in nature, aiming to investigate the phenomenon of “brain rot”, with a focus on its key pillars, psychological factors, digital behaviors, and the cognitive impact resulting from the overconsumption of low-quality digital content. Methods: This study employs a rapid review approach, examining research published between 2023 and 2024 across PubMed, Google Scholar, PsycINFO, Scopus, and Web of Science. It explores the causes and effects of brain rot, focusing on the overuse of social media, video games, and other digital platforms. Results: The findings reveal that brain rot leads to emotional desensitization, cognitive overload, and a negative self-concept. It is associated with negative behaviors, such as doomscrolling, zombie scrolling, and social media addiction, all linked to psychological distress, anxiety, and depression. These factors impair executive functioning skills, including memory, planning, and decision-making. The pervasive nature of digital media, driven by dopamine-driven feedback loops, exacerbates these effects. Conclusions: The study concludes by offering strategies to prevent brain rot, such as controlling screen time, curating digital content, and engaging in non-digital activities. Given the increasing prevalence of digital engagement, it is essential to explore a variety of strategies, including mindful technology use, to support cognitive health and emotional well-being. The results can guide various stakeholders—policymakers, practitioners, researchers, educators, and parents or caregivers—in addressing the pervasive impact of brain rot and promoting a balanced approach to technology use that fosters cognitive resilience among adolescents and young adults. Full article

The rapid advancement of artificial intelligence (AI) technologies has transformed various sectors, significantly enhancing processes and augmenting human capabilities. However, these advancements have also introduced critical concerns related to the safety, ethics, and responsibility of AI systems. To address these challenges, the principles of the robustness, interpretability, controllability, and ethical alignment framework are essential. This paper explores the integration of metacognition—defined as “thinking about thinking”—into AI systems as a promising approach to meeting these requirements. Metacognition enables AI systems to monitor, control, and regulate the system’s cognitive processes, thereby enhancing their ability to self-assess, correct errors, and adapt to changing environments. By embedding metacognitive processes within AI, this paper proposes a framework that enhances the transparency, accountability, and adaptability of AI systems, fostering trust and mitigating risks associated with autonomous decision-making. Additionally, the paper examines the current state of AI safety and responsibility, discusses the applicability of metacognition to AI, and outlines a mathematical framework for incorporating metacognitive strategies into active learning processes. The findings aim to contribute to the development of safe, responsible, and ethically aligned AI systems. Full article

Background/Objectives: Improving food safety practices among young adults is critical to public health, but effective communication strategies are under-researched. This study investigated the effectiveness of a 12-day message-based intervention to promote safe food handling practices using a randomised controlled trial. Methods: A total of 588 participants (aged 18 to 35 years) were randomly assigned to one of four experimental conditions or to a control group. Participants in the intervention groups received daily messages via a mobile app, while the control group received no messages. The intervention combined belief-based content to raise awareness with skill-based content to teach practical food handling, framed by either positive or negative emotional appeals. The experimental conditions differed in message congruence, with belief-based and skill-based content framed either consistently (both positive or both negative) or inconsistently (one positive, one negative). To assess the impact of the intervention, self-reported adherence to food safety practices, food safety awareness, and self-efficacy were measured at baseline and post-intervention. Results: The results showed that the intervention significantly improved food safety practices, especially when the messages were congruent in valence. Pre-intervention self-efficacy moderated the effects, with higher self-efficacy increasing receptivity to certain messages, while lower self-efficacy benefited from a different framing. Self-efficacy, but not awareness, mediated behaviour change, highlighting its key role in the success of the intervention. Conclusions: These results emphasise the importance of message valence congruence and individual self-efficacy levels in designing effective food safety interventions. Future research should investigate long-term intervention effects, adaptive mHealth strategies, and tailored communication approaches to maximise engagement and sustained behaviour change. Full article

With the increasing prevalence of diabetes and its growing impact on maternal and fetal health, management during pregnancy has become critical. This review describes the pathophysiology of insulin resistance during pregnancy, adverse outcomes correlated with diabetic pregnancies, and current management strategies. We investigate two leading approaches to managing pregnant patients with diabetes—lifestyle intervention and drug treatment. Lifestyle intervention, including dietary counseling, exercise regimens, patient education, and self-administered blood glucose monitoring, has demonstrated promising results in the management and prevention of gestational diabetes mellitus (GDM). Early intervention and treatment of at-risk patients have been critical for positive outcomes. Drug treatment, focusing on the utilization of insulin, insulin analogs, and antihyperglycemic agents has shown efficacy in achieving glycemic control and improving maternal and neonatal outcomes. These findings indicate that a combination of early lifestyle intervention and targeted drug treatment yields the most benefit in managing diabetes in pregnancy. To augment treatment, continuous glucose monitoring and telemedicine have become valuable tools in managing diabetes during pregnancy. Future research should aim to develop more effective antihyperglycemic agents, improve telehealth accessibility, and enhance preconception care for women at risk of developing GDM. By addressing these areas, we can significantly reduce the adverse outcomes associated with diabetes in pregnancy and improve overall maternal and fetal health. Full article

Including an n-doped layer in asymmetric double quantum wells restricts confined carriers into V-shaped potential profiles, forming discrete conduction subbands and enabling intersubband transitions. Most studies on doped semiconductor heterostructures focus on how external fields and structural parameters dictate optical absorption. However, electromagnetically induced transparency remains largely unexplored. Here, we show that the effect of an n-doped layer GaAs/Al_xGa_1−xAs in an asymmetric double quantum well system is quite sensitive to the width and position of the doped layer. By self-consistently solving the Poisson and Schrödinger’s equations, we determine the electronic structure using the finite element method within the effective mass approximation. We found that the characteristics of the n-doped layer can modulate the resonance frequencies involved in the electromagnetically induced transparency phenomenon. Our results demonstrate that an n-doped layer can control the electromagnetically induced transparency effect, potentially enhancing its applications in optoelectronic devices. Full article

In this study, we examine the bifurcations and dynamics of a piecewise linear van der Pol equation—a model that captures self-sustained oscillations and is applied in various scientific disciplines, including electronics, neuroscience, biology, and economics. The van der Pol equation is transformed into a piecewise linear system to simplify the analysis of stability and controllability, which is particularly beneficial in engineering applications. This work explores the impact of increasing the number of linear segments on the system’s dynamics, focusing on the stability of the equilibria, phase portraits, and bifurcations. The findings reveal that while the bifurcation structure at critical values of the bifurcation parameter is complex, the topology of the piecewise linear model remains unaffected by an increase in the number of linear segments from three to four. This research contributes to our understanding of the dynamics of nonlinear systems with piecewise linear characteristics and has implications for the analysis and design of real-world systems exhibiting such behavior. Full article

Background and Objectives: Contemporary caries treatment seeks to preserve hard dental tissues as well as to promote lesion remineralization and biological tissue regeneration. While fluoride-based treatments remain the gold standard, their effectiveness has limitations, prompting interest in innovative remineralization technologies. Nano-hydroxyapatite (nano-HA) varnish and self-assembling peptide (SAP) P11-4 are promising biomimetic materials that promote enamel repair, yet long-term data on their efficacy are limited. The objectives of this study were to evaluate the effectiveness of nano-HA varnish and peptide P11-4 in restoring enamel surface hardness after artificial lesions in vitro and to compare them to a control group and fluoride varnish. Materials and Methods: Artificial enamel lesions were created on the buccal surfaces of 36 extracted human molars, which were randomly divided into four groups (n = 9): control, peptide P11-4, fluoride varnish, and nano-hydroxyapatite varnish. After applying the materials as per manufacturer instructions, specimens were stored in artificial saliva for 14 days. Enamel surface hardness was measured using the Vickers hardness test (HV) at baseline, after demineralization, and after remineralization. Statistical analysis was performed with “IBM SPSS 27.0” using non-parametric Kolmogorov–Smirnov, Kruskal–Wallis, Dunn’s, and Wilcoxon tests. Results: The mean baseline enamel hardness value was 323.95 (SD 33.47) HV. After 14 days of demineralization, the mean surface hardness of artificial enamel lesions significantly plummeted to 172.17 (SD 35.96) HV (p = 0.000). After 14 days of remineralization, the mean value significantly increased to 213.21 (SD 50.58) HV (p = 0.001). The results of the study revealed statistically significant enamel remineralization of the peptide P11-4 group in regard to the demineralized enamel (p < 0.05). In contrast, there were no significant results in other treatment groups (p > 0.05). Remineralization of enamel was the highest in samples from the P11-4 group (54.1%), followed by the nano-HA group (35.4%), FV group (17.8%), and control group (11.2%). There was a significant difference (p < 0.05) in the remineralizing ability between the peptide P11-4 and all other treatment groups. Conclusions: Self-assembling peptide P11-4 effectively remineralized artificial enamel lesions and proved to be significantly more effective compared to fluoride varnish and nano-hydroxyapatite varnish, showcasing its superior performance as a remineralizing agent. Full article

Internet addiction has been associated with decreased prosocial behavior in adolescents, and minority studies have investigated the underlying mechanisms involved. This study aimed to examine the mediating effects of self-control and the moderating effects of peer rejection. A longitudinal study with two waves (6 months apart) was used to measure internet addiction (T1), peer rejection (T1), self-control (T1/T2), and prosocial behavior (T1/T2) among 1048 secondary school students (M_age = 14.80 years old, SD = 1.61) in a southern Chinese metropolitan area. A longitudinal path analysis model was applied to analyze the data and derive insights about the relationships between these variables. The findings indicated that T1 internet addiction negatively influenced later prosocial behavior through reduced self-control, particularly among adolescents with lower levels of peer rejection. These findings clarify how internet addiction impairs prosocial development, and we propose a framework for intervention: mitigating peer rejection and harnessing self-control as a mediator to counteract the adverse effects of internet addiction. Full article

The compound energy system is an important component of zero-carbon buildings. Due to the complex form of the system and the difficult-to-capture characteristics of thermo-electric coupling interactions, the operation control of the zero-carbon building’s energy system is difficult in practical engineering. Therefore, it is necessary to carry out relevant optimization methods. This paper investigated the current research status of the control and scheduling of compound energy systems in zero-carbon buildings at home and abroad, selected a typical zero-carbon building as the research object, analyzed its energy system’s operational data, and proposed an operation scheduling algorithm based on day-ahead flexible programming and intraday rolling optimization. The multi-energy flow control algorithm model was developed to optimize the operation strategy of heat pump, photovoltaic, and energy storage systems. Then, the paper applied the algorithm model to a typical zero-carbon building project, and verified the actual effect of the method through the actual operational data. After applying the method in this paper, the self-absorption rate of photovoltaic power generation in the building increased by 7.13%. The research results provide a theoretical model and data support for the operation control of the zero-carbon building’s compound energy system, and could promote the market application of the compound energy system. Full article

In our previous research work, we investigated different methods to mitigate the vortex rope that appears in the draft tube of a Francis turbine when it operates at off-design operating points. The most promising results were obtained for a method involving an axial jet of water. The minor disadvantage of this method was the high value of the flow rate of the water jet. Our present work focuses on another method that decreases the value of the flow rate of the jet. In this sense, a new device has been developed that produces a pulsating water jet, which mitigates the pressure fluctuations associated with the swirling flows. The objective of this paper is to use our experimental test rig to validate the efficiency of a pulsating water jet in mitigating the vortex rope. To perform that, pressure measurements were carried out at four test levels to evaluate the pressure amplitude evolution when the pulsating jet was deployed. From preliminary investigations, the results indicate that this method leads to a decrease of the pressure amplitude of the vortex rope, with a lower value of the flow rate of the jet. Full article