Search Results (8,990)

Background: Alcohol use disorder (AUD) is a chronic relapsing brain disorder characterized by compulsive alcohol seeking, loss of control over drinking, and negative emotional states when not using. It has significant psychological, physiological, and social consequences, often co-occurring with mental health disorders such as depression and anxiety. Psychological resilience is gaining more recognition. Sense of coherence (SOC) could be treated as a health factor, and individual predispositions play a crucial role in fighting disease and addiction. Our study examines whether SOC and its components—comprehensibility, manageability, and meaningfulness—predict life satisfaction in patients with AUD and whether perceived stress and health behaviors mediate these relationships. Methods: The study was conducted on a sample of 100 adult patients diagnosed with alcohol use disorder. Results: We found that the higher the manageability and meaningfulness, the lower the level of perceived stress and the higher the level of preventive behavior. Notably, perceived stress emerged as a significant mediator between SOC and satisfaction with life, while health behaviors did not show a mediating effect. Conclusions: The findings emphasize the protective role of SOC in enhancing psychological well-being among individuals with AUD and suggest that interventions aimed at strengthening SOC may reduce stress and improve overall life satisfaction in this population. Full article

This study uses a U-shaped aqueduct structure in a specific irrigation area as the research object to examine the damage patterns of large-span elevated U-shaped aqueduct structures under seismic action. A single-span aqueduct model that integrates fluid–structure interaction is created with the finite element program ANSYS. The incremental dynamic analysis approach is utilized to perform nonlinear dynamic time–history assessments for three types of bearings—plate rubber bearings, pot rubber bearings and lead-core rubber bearings—under conditions of an empty condition, a half-full condition and a design water level. Seismic fragility curves for the bearings and piers subjected to transverse seismic stress are developed using capacity–demand ratio models and specified damage limit states. The findings demonstrate that the likelihood of aqueduct components being damaged increases substantially as seismic intensity increases, with bearings failing before piers. Under the conditions of empty, half-full and design water levels, the structural mass increases as a result of higher water levels. This alters the dynamic response characteristics and increases the likelihood of failure in a variety of damage states. The probability of plate rubber bearings experiencing minor damage exceedance increases from 11.75% to 61.6% as the water level rises from vacant to design conditions. Lead-core rubber bearings provide better seismic isolation than plate rubber bearings and pot rubber bearings. This greatly lowers the aqueduct structure’s displacement response and damage likelihood. Under design water level circumstances, the chance of mild damage to lead rubber bearings is 8.64%, at a peak ground acceleration of 0.4 g. The damage probabilities for the pot rubber bearings and the plate rubber bearings are 80.68% and 97.45%, respectively. The research findings establish a theoretical foundation for the seismic design and damage evaluation of aqueduct structures in places with high seismic activity, ensuring the stable operation of water transfer projects and sustainable water resource utilization, presenting considerable technical applicability. Full article

Background: The use of benzodiazepines among university students has been scarcely investigated. This situation raises particular concerns in medical students, due to their exposure to stressful situations and, especially, their familiarity with psychotropic drugs. Material and methods: A descriptive cross-sectional observational study was conducted using an anonymous online survey disseminated among universities in the Community of Madrid during April 2024. Results: 25.07% of students stated they had used benzodiazepines at least once, especially from the third academic year onwards. The prevalence was higher among medical students (32.34%). Use was mainly occasional, although 20.21% reported daily use. Among the reasons for use, managing academic stress reached 45.74%. Up to 15.96% of respondents reported a feeling of dependence, and 32.26% noticed concentration difficulties as a side effect of benzodiazepine use. Conclusions: Benzodiazepine use is a relevant phenomenon among university students, with particular incidence in medical degrees. Its onset usually coincides with advanced stages of the degree, which underscores the need for preventive interventions tailored to the academic environment and for the rational use of psychotropic drugs in young populations. Full article

The field of human–robot collaboration (HRC) still lacks research studies regarding the evaluation of mental workload (MWL) through objective measurement to assess the mental state of operators in assembly tasks. This research study presents a comparative neuroergonomic analysis to evaluate the mental workload and productivity in three laboratory experimental conditions: in the first, the participant assembles a component without the intervention of the robot (standard scenario); in the second scenario, the participant performs the same activity in collaboration with the robot (collaborative scenario); in the third scenario, the participant is fully guided in the task in collaboration with the robot (collaborative guided scenario) through a system of guiding labels according to Poka-Yoke principles. The assessment of participants’ mental workload is shown through combinative analysis of subjective (NASA TLX) and objective (electroencephalogram—EEG). Objective MWL was assessed as the power waves ratio β/α (Beta—stress indicator, Alpha—relaxation indicator). Furthermore, the research used observational measurements to calculate the productivity index in terms of accurately assembled components across the three scenarios. Through ANOVA RM, mental workload significantly decreased in the activities involving the cobot. Also, an increase in productivity was observed shifting from the manual scenario to the cobot-assisted one (18.4%), and to the collaborative guided scenarios supported by Poka-Yoke principles (33.87%). Full article

The design of cycloidal reducers requires a detailed knowledge of the intensity and character of load, as well as the maximum von Mises stresses on critical components. In the available literature, the load distribution and the stress–strain state of the cycloidal reducer elements are typically determined based on factors such as cycloidal disc tooth profile modifications, contact deformations, and internal clearances, whereas the influence of thermal stresses is most often neglected. To address this research gap, an innovative numerical–analytical methodology has been developed, which, for the first time, enables the prediction of the distribution of temperature fields and the quantification of the influence of temperature on the contact forces and the stress–strain state of key elements of the cycloidal reducer. Furthermore, the proposed methodology can be adapted for application within a broader context of mechanical engineering. From a practical perspective, it is expected to be beneficial to companies engaged in the design of power transmission gearboxes, as valuable practical guidelines for engineering applications are provided. This study also provides new insights into the dominant sources of heat generation and offers a clearer understanding of how thermal energy is transferred from internal heat sources to the outer surface of the housing. Full article

Background/Objectives: Sphingolipids are a class of lipids that play important structural and functional roles in the cell. Specific ceramide species are distinguishable through the fatty acid that is acylated to the sphingosine backbone, leading to distinct biological activities. Generally, long-chain (LC) ceramides (16:0 and 18:0) drive metabolic dysfunction resulting in the progression of different disease states, while very long-chain (VLC) ceramides (22:0 and 24:0) are thought to be either beneficial against disease progression or benign. In this study, we sought to alter the cellular composition of LC and VLC ceramides in ventricular HCMs to investigate how alterations in these lipids can affect the transcriptome of otherwise healthy HCMs. Methods: Here, we used specific siRNA to knockdown the ceramide synthases responsible for the production of LC and VLC ceramides in ventricular HCMs and investigated the changes in the transcriptome of HCMs with CERS2 or CERS5/6 silenced compared to control conditions. Results: Knocking down CERS2 led to an increase in cell death as well as widespread reductions in cellular VLC sphingolipids. Additionally, we demonstrated that VLC sphingolipid species may play a protective role in maintaining cardiovascular function and that reducing these lipids may contribute to cardiac dysfunction. Similarly, knocking down CERS5 and CERS6 led to reduced LC ceramides and also resulted in profound changes in gene transcription. Interestingly, multiple genes and pathways were affected in the opposite direction when compared to the changes observed with the CERS2 knockdown. Conclusions: Taken together, our results suggest pathways through which VLC ceramides may contribute to cardiac protection, and pathways where LC ceramides may promote HCM stress and the development of cardiac disease. Full article

Background/Objectives: Generalized anxiety disorder (GAD) is one of the most commonly diagnosed anxiety disorders in primary care. The global lifetime prevalence of GAD is estimated at 3.7%, ranging from 1.6% in low-income countries to 5.0% in high-income countries, underscoring its widespread impact. Given the frequent co-occurrence of GAD with obesity, this association has important clinical implications, particularly for screening, prevention, and treatment strategies. The aim of this review is to identify potential biological mechanisms linking obesity and GAD, summarize the current state of knowledge in this area, and highlight existing research gaps, as well as directions for future research. Methods: This narrative review is based on the literature published between 2015 and 2025 concerning the co-occurrence of GAD and obesity, with a focus on potential shared mechanisms including HPA axis dysregulation, chronic inflammation, oxidative stress, insulin resistance, gut–brain axis and microbiota dysbiosis, sleep disturbance, and maladaptive eating behaviors. Results/Conclusions: A growing body of evidence suggests an important, albeit still ambiguously defined, relationship between obesity and GAD. GAD and obesity may reinforce each other, leading to a mutually reinforcing relationship. Despite growing interest, high-quality prospective and interventional studies focusing specifically on GAD are lacking. A potentially effective therapeutic approach should be integrated and multidisciplinary, combining psychological, pharmacological, and lifestyle interventions. It may also be beneficial for clinicians to consider routine assessment of anxiety in patients with obesity and, conversely, to monitor metabolic risk in individuals with GAD. Such an approach, targeting both mental and metabolic domains, holds promise for improving outcomes. Full article

The evaluation of the interfacial shear strength between sand and steel materials plays a fundamental role in the design of geotechnical foundations and structures. However, testing equipment cannot consider the dual effects of particle size and steel roughness on a uniform stress state. In this study, a novel torsion shear apparatus was designed that can measure arbitrary displacement within the interface. On this basis, the influence of the sand particle size and contact surface roughness on interface shear behavior was studied, and the sand–steel interface mechanical responses, including stress state, sample deformation, and friction properties, were evaluated. The results of the torsional interface shear test (TIST) were compared with those of the conventional direct interface shear test (DIST). The results indicate that the shear strength of rough interfaces exceeds that of smooth interfaces but remains below the shear strength observed in pure soil shear tests. Moreover, a critical value of relative roughness exists, beyond which the peak shear stress or friction angle does not significantly increase. Despite variations in the sand grain sizes used in the tests, the corresponding friction angles were approximately equal. In pure soil shear tests, the friction angle was positively correlated with grain size, indicating that grain size directly affects the friction angle in pure soil shear. Additionally, the normalized interface friction angles obtained from the torsional interface shear tests showed good agreement with those derived from interface direct shear tests. Full article

Objectives: Although 3D-printing has been identified as a promising technique for personalised medicine manufacturing, developing complex formulations that are suitable for the process can be challenging. This study evaluates the use of a mixture design for the targeted development of an optimised formulation designed for the 3D-printing of oral dosage forms containing the drug sertraline hydrochloride featuring immediate-release drug dissolution. Methods: The polymers Eudragit E PO, Kollidon 17 PF and hydroxypropyl cellulose were compared in simple screening experiments regarding their extrudability, printability and disintegration. A combination of Eudragit E PO and Kollidon 17 PF proved superior and therefore served as the basis for the mixture design. The resulting blends were processed via hot melt extrusion to produce filaments, which were then measured for bending stress using a 3-point-bending-test, and 3D-printed sample plates were used to determine the crystallinity index of sertraline hydrochloride using X-ray diffraction in a previously identified range with low interference from the other components. The formulation was optimised using statistically based models with the aim of minimising the bending stress to obtain flexible, process-robust filaments and simultaneously minimising the crystallinity index with the intention of improving the solubility of the drug by maximising its amorphous content. Results: The filaments made from the optimised formulation could be reliably printed, and the amorphous state of the active ingredient therein was confirmed. The oral dosage forms produced from these showed immediate release characteristics in an acidic medium. Conclusions: This study demonstrates the advantages of a mixture design for optimising complex formulations in a time- and resource-efficient way and could serve as a basis for other research groups to develop innovative, customisable drug delivery systems more effectively. Full article

The electromagnetic vibration characteristics of doubly fed induction machines (DFIMs) employed in variable-speed pumped storage units, which must accommodate frequent power response and operational mode transitions, serve as critical indicators for assessing unit safety and stability. Nevertheless, there persists a significant research gap regarding generalized vibration analysis models and comprehensive investigations into their steady-state and dynamic vibration performance. To address this challenge, this study develops a universal analytical model for electromagnetic excitation forces in DFIMs using Maxwell’s stress tensor method, explicitly incorporating operational conditions such as rotor eccentricity and load imbalance. Using a 300 MW DFIM as a case study, we employ a hybrid numerical-analytical approach to examine the detrimental effects of harmonic currents generated by rotor-side converters. Furthermore, we systematically analyze how spatial harmonics induced by mechanical faults and temporal harmonics arising from electrical faults collectively influence the electromagnetic vibration behavior. Experimental validation conducted on a 10 MW DFIM prototype through vibration displacement measurements confirms the efficacy of the proposed analytical framework. Full article

Xanthophylls are carotenoids with diverse roles in stress protection across all taxa of life. This review highlights chloroplast-localized xanthophylls (with a focus on zeaxanthin) of plants by presenting an overview of the protective effects of xanthophylls as well as the role of carotenoids as precursors of multiple plant stress hormones. It also examines the roles of xanthophylls and stress hormones in signaling cascades between the chloroplast and nuclear genes that control plant growth, development, and stress defenses. This overview addresses the biosynthetic pathways of xanthophylls and carotenoid-derived plant stress hormones, functions of xanthophylls in photoprotection of photosynthesis, carotenoids as essential human micronutrients, and roles of xanthophylls in membrane integrity. Attention is given to the involvement of zeaxanthin in both abiotic and biotic defense as well as its impact on components of the biotic defense system with contrasting targets. Examples for the multiple principal loops of signaling cascades between the chloroplast and nucleus, which are based on chloroplast redox state and modulated by xanthophylls, are summarized. This review integrates the role of chloroplast carotenoids in controlling light-use efficiency and providing photoprotection with their system-wide regulatory effects as precursors of carotenoid-derived plant stress hormones and modulators of chloroplast redox state. A better understanding of these connections is needed to guide development of plant lines with improved resilience and productivity in complex, changing, and challenging environments. Full article

With the ongoing electrification of vehicles and the resulting demand for higher power densities, drivetrain requirements are becoming increasingly stringent. Shaft-hub connections are particularly affected in terms of both quantity and design, making innovative solutions necessary. A key factor in meeting these requirements is knowledge of the stress state within the contact area. One promising approach is the application of a thin-film-based sensor system directly onto the shaft surface. This enables, for the first time, the direct measurement of contact pressure in the interface, allowing for more precise connection design. To fully exploit the potential of this sensor technology, its influence on the joining process of shaft-hub connections must be investigated. In this study, cylindrical interference-fits were coated with two thin-film systems relevant to the application, followed by joining tests. The resulting damage was analyzed to derive general recommendations for the joining of coated shaft-hub connections. The results show that shrink-fitting enables damage-free joining, provided specific parameters are met, as confirmed by experimental testing and microscopic examination. This not only preserves the integrity of the sensor system but also establishes the prerequisite for potential in situ measurements, thereby laying the foundation for the feasibility of direct load monitoring during operation. Full article

In deep-sea mining operations, rigid risers operate in a complex and uncertain ocean environment where vessel–riser interactions present significant structural challenges. This study develops a coupled dynamic modeling framework that integrates vessel motions and environmental loads to evaluate the probabilistic risk of riser failure. Using frequency-domain RAOs derived from AQWA and time-domain simulations in OrcaFlex 11.0, we analyze the riser’s effective tension, bending moment, and von Mises stress under a range of wave heights, periods, and directions, as well as varying current and wind speeds. A Monte Carlo simulation framework based on Latin hypercube sampling is used to generate 10,000 sea state scenarios. The response distributions are approximated using probability density functions to assess structural reliability, and global sensitivity is evaluated using a Sobol-based approach. Results show that the wave height and period are the primary drivers of riser dynamic response, both with sensitivity indices exceeding 0.7. Transverse wave directions exert stronger dynamic excitation, and the current speed notably affects the bending moment (sensitivity index = 0.111). The proposed methodology unifies a coupled time-domain simulation, environmental uncertainty analysis, and reliability assessment, enabling clear identification of dominant factors and distribution patterns of extreme riser responses. Additionally, the workflow offers practical guidance on key monitoring targets, alarm thresholds, and safe operation to support design and real-time decision-making. Full article

Background/Objectives: For runners competing abroad in sports events, the hours before a race are marked by heightened psychological tension, where even food choices can feel crucial to success. While pre-race nutrition is often addressed in terms of physiological needs, little is known about the inner psychological processes that accompany food decisions in unfamiliar cultural and environmental contexts. This study explores the inner dialogues, anxieties, and coping mechanisms of international runners facing the question of whether and what to eat before competition. Methods: A qualitative study was conducted with twelve international participants (from the United Kingdom, Germany, and Ukraine) of the Poznan Half Marathon 2025. Data were collected through semi-structured in-depth interviews. Participants possessed a minimum of two years’ experience competing in international events. Results: Three thematic areas were identified: (1) anticipatory anxiety and fear of making nutritional mistakes before the race, (2) internal negotiation between prior nutritional knowledge and situational trust, and (3) ritualization and individualized norms as fundamental mechanisms of psychological regulation. These themes influenced how runners experienced pre-race nutrition, shaping their emotional states, decision-making processes, and coping strategies in the context of international competition. Conclusions: Pre-race nutrition decisions are deeply embedded in emotional and cognitive landscapes shaped by stress, cultural context, and individual history. Recognizing these inner dynamics can help coaches, sports nutritionists, and event organizers better support the psychological well-being of traveling athletes. Full article

Background/Objectives: Diet and obesity contribute to approximately 50% of tumor development. Therefore, nutrition plays a key role not only in cancer prevention but also in determining prognosis. Notably, between 30% and 90% of cancer patients experience malnutrition. Furthermore, the hypercatabolic state induced by tumors leads to widespread protein degradation, clinically manifesting as sarcopenia or cachexia, and ultimately accelerating mortality. This narrative review examines the potential role of amino acids (AAs) in inhibiting tumor growth and counteracting protein–energy malnutrition—aiming to preserve muscle mass and nourish healthy cells while placing neoplastic cells in a state of metabolic stress. Methods: The analysis was conducted following the Standards for Reporting Qualitative Research guidelines. Results: Administration of targeted mixtures of essential amino acids (EAAs) has been shown to improve muscle mass, strength, and quality of life in patients with hypercatabolic conditions. Experimental in vitro and in vivo studies also suggest a potential inhibitory effect on tumor proliferation. However, increased availability of certain AAs may, in some cases, stimulate tumor growth, one reason why EAAs supplementation in cancer patients remains controversial. Conclusions: Despite prevailing concerns, emerging evidence indicates that supplementation with a complete, well-balanced EAAs formulation may be a valuable adjunct to standard cancer therapies. This approach could help correct cancer-associated protein imbalances, enhance patients’ quality of life, and create a metabolic environment unfavorable to tumor progression. Full article