Search Results (446)

Background: Malnutrition and sleep disturbances are common in childhood and are associated with neuropeptides that regulate appetite and circadian rhythms. Hypothalamic peptides such as orexin A, agouti-related protein (AgRP), proopiomelanocortin (POMC), and peptide YY (PYY) play important roles in energy balance and eating behavior; however, their specific functions in pediatric malnutrition remain unclear. This study aimed to determine the levels of these peptides in malnourished children and to examine their relationship with eating and sleep behaviors. Methods: This case–control, cross-sectional study included 99 children aged 5–15 years diagnosed with malnutrition and 85 age-matched healthy controls. Blood samples were collected from all participants, and peptide levels were measured using ELISA. Additionally, the Children’s Eating Behaviour Questionnaire (CEBQ) and the Children’s Sleep Habits Questionnaire (CSHQ) were administered to assess eating patterns and sleep behaviors. Statistical comparisons and hierarchical logistic regression analyses were performed. Results: Orexin A and PYY levels were significantly higher in malnourished children than in controls (p < 0.001). No significant group differences were found for AgRP and POMC, although AgRP tended to be lower and POMC higher in the malnutrition group. Regression analyses identified orexin A and PYY as significant predictors of malnutrition. Orexin A showed a positive correlation with emotional undereating. Sleep habits did not differ significantly between groups. Conclusions: Elevated orexin A and PYY levels may function as potential neuropeptidergic biomarkers of malnutrition. Their association with emotional eating highlights the psychobiological components of malnutrition. Further longitudinal studies are warranted to clarify causal mechanisms and support clinical translation. Full article

To address the challenges inherent in the transition flight control of QTR UAVs, this paper proposes an asynchronous tilt transition control framework that integrates NDIC with an ESO. First, a heterogeneous control allocation strategy is introduced to coordinate the rotors and aerodynamic surfaces, thereby maintaining consistent matching between control demands and actuator capabilities. Furthermore, compared with the synchronous tilt strategy, the proposed asynchronous tilt strategy improves pitch moment balance and forward acceleration capability, thereby enhancing robustness against CG variations and extending the achievable forward acceleration range. Finally, based on the asynchronous tilt transition strategy, a transition flight control method combining NDIC with ESO is presented to achieve precise transition control performance under the lumped disturbances. The simulation results demonstrate that the proposed tilt method achieves a safe and smooth transition, satisfies dynamic performance requirements, and exhibits strong robustness and high control accuracy. Full article

Objectives: Polycystic ovary syndrome (PCOS) is a heterogeneous disorder with diverse pathogenetic mechanisms and clinical manifestations. Phenotype D PCOS is characterized by oligomenorrhoea and polycystic ovaries without hyperandrogenism. Altered adipokine profiles may contribute to reproductive and metabolic disturbances. Chemerin is an adipokine involved in inflammatory and metabolic processes. It remains unclear whether altered chemerin levels in PCOS reflect metabolic dysfunction alone or are directly associated with hyperandrogenism. The aim of this study was to compare serum chemerin levels in women with normoandrogenic PCOS and a control group. Methods: This cross-sectional preliminary study included 49 women with phenotype D PCOS and 40 healthy, age- and body mass index (BMI)-matched controls. Anthropometric, biochemical, hormonal parameters, and serum chemerin concentrations were assessed. Results: Serum chemerin concentrations did not differ significantly between the groups. In the PCOS group, the 95% confidence interval ranged from 198.61 to 234.37, while in the controls, it ranged from 187.13 to 216.21. In women with PCOS, chemerin showed significant positive correlations with weight, BMI, waist and hip circumference, total adipose tissue, and both gynoid and android fat content. Positive correlations were also observed with highly sensitive C-reactive protein (hs-CRP), insulin, glucose, triglycerides, and Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), and a negative correlation was found with high-density lipoprotein (HDL) cholesterol. Chemerin was weakly negatively correlated with sex hormone binding globulin (SHBG) and positively correlated with the free androgen index (FAI). In the control group, chemerin correlated positively with CRP, insulin, triglycerides, total and gynoid adipose tissue, and negatively correlated with HDL cholesterol and SHBG. Conclusions Although chemerin levels did not differ from controls, chemerin was associated with metabolic and inflammatory markers in both groups. These findings should be considered preliminary due to the limited sample size. Chemerin may reflect metabolic and inflammatory status rather than hyperandrogenism in normoandrogenic PCOS. Full article

Ground-based full-physical experiments for space rendezvous and docking serve as a critical step in verifying the reliability of docking technology. The high-precision active attitude setting of spacecraft simulators represents a key technology for ground-based full-physical experiments. In order to satisfy the requirement for high-precision attitude control in these experiments, this paper proposes an enhanced method based on auto disturbance rejection control (ADRC). This paper addresses the limitations of traditional deadband–hysteresis relay controllers, which exhibit low steady-state accuracy and insufficient disturbance rejection capability. This approach employs a nonlinear extended state observer (NESO) to estimate and compensate for total system disturbances in real time. Concurrently, it incorporates an adaptive mechanism for deadband and hysteresis parameters, dynamically adjusting controller parameters based on disturbance estimates and attitude errors. This overcomes the trade-off between accuracy and power consumption that is inherent in fixed-parameter controllers. Furthermore, the method incorporates a nonlinear tracking differentiator (NTD) to schedule transitions, enabling rapid attitude settling without overshoot. The stability analysis demonstrates that the proposed controller achieves local asymptotic stability and global uniformly bounded convergence. The simulation results demonstrate that under three typical operating conditions (conventional attitude setting, pre-separation connector stabilisation, and docking initial condition establishment), the steady-state attitude error remains within ±0.01°, with convergence times under 3 s and no overshoot. These results closely match ground test data. This approach has been demonstrated to enhance the engineering applicability of the control system while ensuring high precision and robust performance. Full article

Background: The development of lung cancer is strongly influenced by oxidative stress (OS), which results when the balance between oxidants and antioxidants is disturbed. Evaluation of both specific redox markers such as thiol/disulfide homeostasis (TDH) and overall indicators including total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) may provide a more comprehensive view of oxidative imbalance in lung cancer. We examined OS indices and TDH in patients with lung cancer versus healthy controls. Methods: Eighty participants were enrolled, consisting of 40 patients with newly diagnosed lung cancer and 40 age- and sex-matched healthy controls. Serum levels of native thiol (NT), total thiol (TT), and disulfide were determined using an automated spectrophotometric method. Additionally, TAS, TOS, and the OSI were evaluated to provide an overall assessment of oxidative balance. Routine hematological and biochemical parameters were compared between groups. Results: White blood cell and neutrophil counts were notably higher in lung cancer patients compared with controls (p < 0.05). NT and TT levels were remarkably decreased, whereas disulfide levels, TOS, and OSI were significantly elevated in the lung cancer group (p < 0.05). TAS levels tended to be lower in patients, although not reaching statistical significance. No significant association was observed between oxidative parameters and tumor stage or localization. Conclusions: Patients with lung cancer exhibited a marked oxidative imbalance, characterized by elevated oxidant burden and impaired TDH. Combined assessment of TAS, TOS, OSI, and thiol/disulfide parameters may provide valuable insight into the oxidative pathophysiology of lung cancer and hold potential as complementary biomarkers for disease evaluation. Further large scale studies are needed to confirm these findings. Full article

Covered karst collapse is a key geotechnical hazard in infrastructure construction in karst regions of China. In particular, strata consisting of an overlying clay layer and an underlying sand layer are prone to abrupt collapse induced by sand leakage under construction disturbances, which poses serious risks to pile foundation safety. To clarify the disaster-forming mechanism and develop a quantitative analysis method, this study investigates the mechanical behaviour of the entire collapse process by combining theoretical analysis with numerical simulation. A continuous mechanical analysis framework is established that follows the sequence from sand layer leakage to cavity expansion and then clay layer instability. Within this framework, a calculation model for the angle of repose of the sand layer is proposed that considers seepage and confined pressure effects. Simultaneously accounting for the influence of the casing, stability models for overall and localised collapses are developed using limit equilibrium theory. A comprehensive safety factor criterion K_c based on the critical span (or radius) is then proposed, leading to a linked evaluation method that couples the potential span of the sand layer with the ultimate span of the clay layer. The results show that an increase in Δh/h significantly reduces the angle of repose of the sand layer; the mechanical mechanism is confirmed whereby an increase in the roof span leads to shear stress exceeding the soil’s shear strength, thus triggering instability; the proposed safety factor K_c can effectively predict both overall and localised collapse, and case verification demonstrates that the predicted spans match well with actual collapse dimensions. The results provide a theoretical and technical basis for risk prediction, as well as for the prevention and control of pile foundation construction in karst areas. Full article

High penetration of wind farms into the power grid lowers system inertia and compromises stability. This paper proposes a grid-forming control strategy for Permanent Magnet Synchronous Generator (PMSG) wind turbines based on DC-link voltage matching and virtual inertia. First, a relationship between grid frequency and DC-link voltage is established, replacing the need for a phase-locked loop. Then, DC voltage dynamics are utilized to trigger a real-time switching of the power tracking curve, releasing the rotor’s kinetic energy for inertia response. This is further coordinated with a de-loading control that maintains active power reserves through over-speeding or pitch control. Finally, the MATLAB/Simulink simulation results and RT-LAB hardware-in-the-loop experiments demonstrate the capability of the proposed control strategy to provide rapid active power support during grid disturbances. Full article

Background/Objectives: Children born small for gestational age (SGA) are at increased risk for impaired growth, metabolic disturbances, and neurodevelopmental difficulties. Although previous research has examined cognitive and behavioral outcomes in this population, findings remain inconsistent. Moreover, limited evidence is available regarding the potential effects of recombinant human growth hormone (rhGH) therapy on cognitive development. We aimed to assess cognitive performance, emotional–behavioral functioning, and neonatal predictors of neurocognitive outcomes in term SGA children compared with age- and sex-matched peers born appropriate for gestational age (AGA). We also explored potential differences in cognitive outcomes between rhGH-treated and untreated SGA children. Methods: A total of 18 term SGA children and 23 AGA controls underwent anthropometric measurements, biochemical evaluation, cognitive testing using the Wechsler Intelligence Scale for Children—Fourth Edition (WISC-IV), and behavioral assessment through the Child Behavior Checklist (CBCL). Birth weight, length, and head circumference were analyzed as potential predictors of cognitive performance. Results: SGA children demonstrated significantly lower Intelligence Quotient (IQ) scores than AGA peers, with marked weaknesses in Perceptual Reasoning index (PRI) and Processing Speed index (PSI), while Verbal Comprehension and Working Memory were preserved. They also exhibited higher internalizing behavioral symptoms, whereas externalizing behaviors did not differ between groups. Birth head circumference emerged as a strong predictor of PRI and a modest predictor of PSI. No associations were found between rhGH treatment parameters and cognitive outcomes. Larger longitudinal studies are needed to clarify how early growth restriction affects brain development and cognition and whether GH therapy influences these processes. Full article

Background/Objectives: This study aimed to characterize objective sleep measures in subacute acquired brain injury (ABI) and examine if disturbed sleep is associated with poor recovery outcomes. Another objective was to compare the functional connectivity of the brain between ABI poor sleepers and ABI normal sleepers as measured by resting state functional magnetic resonance imaging (rs-fMRI). Methods: This was a pilot, prospective, observational study of ABI subjects compared with age and gender-matched healthy controls. A total of 27 ABI subjects (consisting of ischemic or haemorrhagic stroke, or traumatic injury) were recruited from the outpatient clinics of a tertiary hospital with a neurological centre, and 49 healthy controls were recruited by word-of-mouth referrals. Study procedure involved subjective and objective sleep measures, self-report psychological measures, cognitive tests, and structural and functional MRI of the brain. Results: The frequency of poor-quality sleep was 66.67% in the ABI group and not significantly different from 67.35% in the control group when compared by chi-squared test (p = 0.68). ABI subjects with poor sleep had worse performance on a test of sustained attention (Colour Trails Test 1) than healthy controls with poor sleep when compared by Student’s t-test (mean 55.95 s, SD ± 18.48 vs. mean 40.04 s, SD ± 14.31, p = 0.01). Anxious ABI subjects have poorer sleep efficiency and greater time spent awake after sleep onset (WASO). ABI-poor sleepers show significantly greater functional connectivity within a frontoparietal network and bilateral cerebellum. Conclusions: Sleep problems after ABI are associated with poorer cognitive and psychological outcomes. ABI-poor sleepers exhibit altered functional connectivity within regions that contribute to motor planning, attention, and self-referential processes, suggesting that disrupted sleep after ABI may impair the integration of sensorimotor and cognitive control systems, and therefore, impair recovery. Full article

Recently, there has been a rapid increase in the demand for magnetic levitation systems. Since they are utilized in many levitation-based systems, one such application is in magnetic levitated (Maglev) trains. Moreover, these systems are complicated to control due to their nonlinear characteristics, susceptibility to external disturbances, and model uncertainties. This article proposes an enhanced integral sliding mode control (ISMC) strategy with a robust optimal framework designed for electromagnetic levitation systems (EMLSs). Traditional sliding mode control (SMC) often suffers from a high-frequency phenomenon in the input, thereby necessitating the development of a more robust controller. This requirement is addressed through the implementation of a comprehensive integral robust optimal sliding mode control strategy. The proposed controller effectively mitigates the chattering phenomenon while simultaneously enhancing the system’s robustness against uncertainties. The robust optimal approach is specifically designed to handle the matched uncertainties inherent in the system dynamics, thereby facilitating an appropriate feedback control mechanism. The Hamilton–Jacobi–Bellman (HJB) equation is used to achieve the robust control design. This feedback control is integrated with the ISMC to execute the desired control action effectively. The simulation results highlight the effectiveness of the proposed control scheme, presenting a comparative analysis of performance indices, including integral time absolute error (ITAE), integral absolute error (IAE), integral squared error (ISE), and integral time squared error (ITSE). These indices collectively underscore the robustness of the control design. Full article

Workforce adjustments, such as mass layoffs, are significant corporate events that can influence stock returns and volatility, yet their broader asset-pricing implications remain underexplored. We examine the impact of such workforce shocks on stock performance from an asset-pricing perspective. Grounded in production-based asset-pricing theory, incorporating labor adjustment costs and search-and-matching frictions, our study posits that disruptions in the labor force significantly affect firm risk and value. This focus addresses a clear gap. Previous research has not comprehensively evaluated workforce shocks as systematic risk factors in a cross-sectional asset-pricing model. Using an extensive dataset spanning 1990–2023 and covering thousands of layoff events, we construct a novel “workforce shock” factor and conduct the first large-scale empirical tests of its pricing relevance. Our analysis reveals that workforce shocks lead to lower stock returns and heightened volatility, effects especially pronounced in labor-intensive firms. Moreover, exposure to workforce shock risk carries a significant premium, indicating that these disruptions act as a systematic risk factor priced in the cross-section of equity returns. Overall, our study provides the first comprehensive evidence linking labor force disturbances to equity risk premia, underscoring the importance of incorporating labor market considerations into asset-pricing models. Full article

Background: Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder characterized by hyperandrogenism, ovulatory dysfunction, and an increased prevalence of metabolic syndrome. Clusterin (CLU), a chaperone protein induced by cellular stress and known to play roles in inflammation, oxidative stress, and lipid metabolism, may be associated with the metabolic abnormalities observed in patients with PCOS. The purpose of this current study is to investigate serum CLU levels and their link with endocrine, biochemical, and metabolic parameters, such as metabolic syndrome, among women with PCOS. Methods: This cross-sectional study included 40 women aged 18–30 with PCOS diagnosed according to the Rotterdam criteria and 40 age- and BMI-matched healthy controls. Demographic data, Ferriman–Gallwey scores, hormonal and metabolic parameters (including TSH, prolactin, 17-OH progesterone, total testosterone, insulin, AMH, HOMA-IR, and serum CLU levels), and ultrasonographic ovarian morphology were assessed. Statistical analyses, including ROC and logistic regression, were performed. Results: Women with PCOS had higher follicle counts, Ferriman–Gallwey scores, LH/FSH ratios, fasting insulin levels, HOMA-IR, triglycerides, and systolic blood pressure than controls, whereas menstrual cycle frequency and HDL levels were lower (all p < 0.05). Serum CLU concentrations were markedly higher in the PCOS cohort. In the PCOS population, CLU showed positive relationships with the Ferriman–Gallwey score, fasting glucose, fasting insulin, HOMA-IR, and triglycerides, and a negative correlation with HDL. CLU levels were significantly higher in women with metabolic syndrome in the PCOS cohort compared to those without. In logistic regression analysis, CLU, AMH, and the LH/FSH ratio emerged as independent predictors of PCOS. Furthermore, CLU remained an independent predictor of metabolic syndrome in the PCOS cohort. In ROC analysis, CLU demonstrated strong diagnostic efficacy in detecting both PCOS (AUC = 0.834) and metabolic syndrome in patients with PCOS (AUC = 0.804). Conclusions: Our results show that serum CLU is higher in women with PCOS and is associated with the clinical and metabolic features peculiar to patients with PCOS. CLU was found to distinguish between patients with PCOS and healthy women and demonstrated a strong association with the presence of metabolic syndrome within the PCOS group. Overall, these findings suggest that CLU may be a valuable auxiliary biomarker for detecting women with PCOS at risk for metabolic disturbances. Full article

In a mother–child underwater bio-inspired robotic system, the equivalent lever arm between the master and slave inertial navigation systems (INSs) varies with launcher attitude changes and structural flexure. This time-varying lever arm introduces hard-to-model systematic velocity errors that degrade the accuracy and filter convergence of velocity difference-based transfer alignment. Traditional rigid body compensation relies on precise, constant lever-arm parameters and fails when booms, launch tubes, or flexible manipulators undergo appreciable deformation or reconfiguration. To address this, we augment a “velocity–attitude joint matching and innovation-based adaptive Kalman filter (AKF)” framework with an attention-based Long Short-Term Memory (LSTM) feed-forward module. Using only a short, real-time Inertial Measurement Unit (IMU) sequence from the slave INS, the module predicts and compensates the velocity bias induced by the lever arm. Numerical simulations of an underwater bio-inspired robot deployment scenario show that, under typical maneuvers (acceleration, turning, fin-flapping, and S-curve), the proposed method reduces the root-mean-square (RMS) misalignment angle error from about 14.5′ to 5.2′ and the RMS installation error angle from 8.8′ to 3.0′—average reductions of about 64% and 66%, respectively—substantially improving the robustness and practical applicability of transfer alignment under time-varying lever arms and flexible disturbances. Full article

Background: Cognitive dysfunction is a frequent but under-recognized feature of fibromyalgia (FM). Its prevalence varies widely across studies, and independent clinical predictors remain uncertain. This study aimed to determine the prevalence of cognitive dysfunction in FM patients compared with healthy controls and identify independent associated factors. Methods: We conducted a case–control study including 47 adult female patients with FM (2016 ACR criteria) and 19 age- and sex-matched healthy controls. Sociodemographic and clinical data were collected. Cognitive function was evaluated using the Montreal Cognitive Assessment (MoCA), with cognitive dysfunction defined as MoCA < 26. Pain (VAS), fatigue (VAS and FACIT-F), anxiety and depression (HADS), sleep quality (PSQI), and disease impact (FIQ-P) were assessed. Univariate analysis was followed by binary logistic regression to identify independent predictors of cognitive dysfunction and multiple linear regression to explore associations with MoCA score. Results: Cognitive dysfunction was present in 72.3% of FM patients versus 5.3% of controls (p < 0.001). FM patients had significantly worse pain scores, fatigue levels, psychological distress, sleep quality, and quality of life (all p < 0.001). In FM patients, MoCA scores correlated inversely with pain (r = −0.34), anxiety (r = −0.34), depression (r = −0.48), disease impact (r = −0.43), and sleep disturbance (r = −0.48), and positively with FACIT-F (r = 0.37) and EQ-5D-5L (ρ = 0.60). In multivariate analysis, higher FIQ-P scores were independently associated with cognitive dysfunction [adjusted OR1.18; 95% CI (1.06–1.30); p < 0.01]. Pain severity [adjusted B = −0.40; 95%CI (−0.64–0.15; p < 0.01)] and depression [adjusted B = −2.60; 95% CI (−4.12–1.04; p = 0.001)] were independently associated with lower MoCA scores. Conclusions: Cognitive dysfunction is highly prevalent in FM and is independently associated with pain severity, depressive symptoms, and disease impact. Full article

In this paper, we propose a mobile target tracking method for airport movement areas based on an adaptive interacting multiple model framework combined with a strong tracking unscented Kalman filter, referred to as the AIMM-STUKF algorithm. The objective is to enhance real-time tracking accuracy, improve model adaptability, and strengthen robustness against abrupt disturbances in complex airport environments. The proposed AIMM-STUKF adopts a standard STUKF formulation within the overall tracking framework, thereby enhancing responsiveness to maneuvering targets. An exponential correction factor is further constructed based on posterior model probability differences to adaptively adjust the Markov transition matrix, enabling self-adaptive mode switching. In addition, airport map information is incorporated to impose constraints on the position components of the filtered state estimates, enhancing the adaptability of the algorithm to the airport operational environment. Experimental validation is conducted through Monte Carlo simulations using representative trajectories that reflect realistic airport operational characteristics. Comparative results with the standard IMM-UKF and two existing AIMM-UKF algorithms demonstrate that the proposed AIMM-STUKF achieves superior performance in terms of tracking accuracy, model matching consistency, mode-switching responsiveness, and robustness against sudden disturbances. Full article