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There are limited studies involving the relationship between preschool teachers' job burnout and their professional engagement and career development aspirations. This study classified latent profiles according to job burnout indices for Chinese preschool teachers and examined the characteristics of each profile and how they affect professional engagement and career development aspirations. A cluster sample of 1000 preschool teachers (54 males and 946 females; average age = 30.93, SD = 9.91) was recruited to complete questionnaires regarding job burnout, professional engagement and career development aspirations. Results indicated that preschool teachers' job burnout can be divided into four latent classes: 1) low burnout (9%); 2) exogenous burnout (42%); 3) endogenous burnout (44%) and 4) high burnout (5%). The demographic variables such as gender, marital status, working years, preschool location and job category have a significant impact on the potential categories of preschool teachers' job burnout. Furthermore, the four categories of job burnout show significant differences in the level of professional engagement and career development aspirations and its dimensions, except the leadership aspiration dimension.

Obvious macroscopic anomalies of geothermal fluids were observed before and after the Mw 7.8 earthquake in Turkey. In order to find out the relationship between geothermal fluid anomalies and earthquakes, we performed a systematic hydrogeochemistry and isotopic analysis of the geothermal fluids in the East Anatolian Fault Zone (EAFZ). The results show that these geothermal fluids were reconstructed (including: energy and materials) by earthquakes. Based on chlorine – enthalpy model, the temperature of the deep geothermal fluid has been increasing to 382 °C on the strength of the energy released by the seismic activity. However, the information of the deep geothermal fluid was eventually covered due to the infiltration of a large amount of shallow cold water after the earthquake. The abnormal concentrations of Ca2+ (54.04~501.58 mg/L), Mg2+ (6.58~116.20 mg/L), SO42– (6.37~287.74 mg/L), Sr (34.78~3244.8 μg/L), and Ba (1.89~196.48 μg/L) in geothermal water shown that the geothermal water has undergone complex water-rock interaction processes such as gypsum, calcite, dolomite, anorthite and serpentinization. Specially, significant gypsum dissolution was observed at HS05, HS09 and HS14 before and after the earthquake, suggesting that the earthquake broke the balance of water-rock reaction and promoted the dissolution of gypsum. Combined with geological background and previous studies, we propose that shallow sedimentary minerals, such as gypsum, have the potential to be used as earthquake warning indicators. However, shallow minerals are controlled by many external factors (e.g., temperature, pressure, climatic conditions, seasonal changes etc.), which greatly weakens their practical value in earthquake early warning. [ABSTRACT FROM AUTHOR]

Wind turbine blades are complex structures composed of multiple bonded components. The fatigue performance of these adhesive joints is crucial for ensuring operational safety over the blade's lifespan. Traditional structural fatigue analysis methods are inadequate for evaluating the fatigue properties of these joints due to the unique characteristics of adhesive materials. Variations in material and dimensional parameters, as well as fluctuating operational loads, further complicate the fatigue analysis of adhesive joints in wind turbine blades. To tackle this issue, this study introduces a fatigue analysis and reliability assessment method for the adhesive joints of wind turbine blades, employing the Cyclic Cohesive Zone Model (CCZM) and accounting for parameter uncertainties. Specifically, a novel methodology for fatigue analysis based on the CCZM is presented. The methodology is programmatically implemented to obtain a fatigue life dataset through multiple simulations, considering uncertainties in material parameters, adhesive dimensions, and loads. Subsequently, a fatigue reliability model is formulated to evaluate the fatigue reliability of adhesive joints in wind turbine blades under different parameter conditions, and the sensitivity of fatigue reliability to each parameter is investigated. The findings offer valuable insights for improving the safety and reliability of adhesive structures in wind turbine blades. [ABSTRACT FROM AUTHOR]

In the entire wind turbine system, the blade acts as the central load-bearing element, with its stability and reliability being essential for the safe and effective operation of the wind power unit. Carbon fiber, known for its high strength-to-weight ratio, high modulus, and lightweight characteristics, is extensively utilized in blade manufacturing due to its superior attributes. Despite these advantages, carbon fiber composites are frequently subjected to cyclic loading, which often results in fatigue issues. The presence of internal manufacturing defects further intensifies these fatigue challenges. Considering this, the current study focuses on carbon fiber composites with multiple pre-existing cracks, conducting both static and fatigue experiments by varying the crack length, the angle between cracks, and the distance among them to understand their influence on the fatigue life under various conditions. Furthermore, this study leverages the advantages of Paris theory combined with the Extended Finite Element Method (XFEM) to simulate cracks of arbitrary shapes, introducing a fatigue simulation method for carbon fiber composite laminates with multiple cracks to analyze their fatigue characteristics. Concurrently, the Particle Swarm Optimization (PSO) algorithm is employed to determine the optimal weight configuration, and the Backpropagation neural network (BP) is used to train and adjust the weights and thresholds to minimize network errors. Building on this foundation, a surrogate model for predicting the fatigue life of carbon fiber composite laminates with multiple cracks under conditions of physical parameter uncertainty has been constructed, achieving modeling and assessment of fatigue reliability. This research offers theoretical insights and methodological guidance for the utilization of carbon fiber-reinforced composites in wind turbine blade applications. [ABSTRACT FROM AUTHOR]

The quality and reliability of wind turbine blades, as core components of wind turbines, are crucial for the operational safety of the entire system. Carbon fiber is the primary material for wind turbine blades. However, during the manufacturing process, manual intervention inevitably introduces minor defects, which can lead to crack propagation under complex working conditions. Due to limited understanding and measurement capabilities of the input variables of structural systems, the distribution parameters of these variables often exhibit uncertainty. Therefore, it is essential to assess the impact of distribution parameter uncertainty on the fatigue performance of carbon-fiber structures with initial cracks and quickly identify the key distribution parameters affecting their reliability through global sensitivity analysis. This paper proposes a sensitivity analysis method based on surrogate sampling and the Kriging model to address the computational challenges and engineering application difficulties in distribution parameter sensitivity analysis. First, fatigue tests were conducted on carbon-fiber structures with initial cracks to study the dispersion of their fatigue life under different initial crack lengths. Next, based on the Hashin fatigue failure criterion, a simulation analysis method for the fatigue cumulative damage life of cracked carbon-fiber structures was proposed. By introducing uncertainty parameters into the simulation model, a training sample set was obtained, and a Kriging model describing the relationship between distribution parameters and fatigue life was established. Finally, an efficient input variable sampling method using the surrogate sampling probability density function was introduced, and a Sobol sensitivity analysis method based on surrogate sampling and the Kriging model was proposed. The results show that this method significantly reduces the computational burden of distribution parameter sensitivity analysis while ensuring computational accuracy. [ABSTRACT FROM AUTHOR]

The fatigue of adhesive joints in offshore wind turbine blades is a critical and widespread challenge, necessitating an urgent focus on adhesive bond reliability. Given the constraints of full-scale testing, this research explores the fatigue endurance of carbon fiber–epoxy adhesive composites, integral to blade construction. Recognizing the fatigue characteristics' sensitivity to environmental factors and joint dimensions, an innovative approach to fatigue modelling and evaluation is introduced. This method incorporates the influence of different environmental stresses and size effects. Specifically, a degradation coefficient and size impact factor (SIF) are introduced into the cyclic cohesive zone model, and a simulation-based analytic approach is proposed for analyzing adhesive fatigue. Furthermore, we introduce a reliability modelling procedure that integrates performance degradation theory to address the deteriorative characteristics inherent in adhesive fatigue. Subsequently, the specimens' damage accumulation increased by 75% because of the stresses and escalated to 85% with adhesive joint size effects, causing carbon fiber Reinforced Polymer/epoxy adhesive joints to fail interfacially rather than in a mixed-mode manner. This study provides valuable insights for the safety analysis and assessment of adhesive joint performance in offshore wind turbine blades. [ABSTRACT FROM AUTHOR]

This study presents a case of dual primary liver cancer involving small cell neuroendocrine carcinoma and hepatocellular carcinoma. The 58-year-old Chinese male patient, who has a medical history of viral hepatitis B, presented with right upper abdominal pain persisting for one month. Imaging studies indicated the presence of multiple liver masses in segments V and VII–VIII, as well as a mass in the left lung. Subsequent hepatic biopsy performed on both segments confirmed the presence of hepatocellular carcinoma in segment V and small cell neuroendocrine carcinoma in segment VII–VIII. After undergoing one cycle of chemotherapy, the lung mass exhibited a reduction in size, while the liver masses showed an inadequate response. Subsequently, the patient underwent Transcatheter Arterial Chemoembolization (TACE) and Hepatic Artery Infusion Chemotherapy (HIAC), resulting in partial remission (PR). However, the patient was diagnosed with brain metastasis and subsequently treated with Sorafenib and Tirelizumab, a Programmed Death 1 (PD-1) immune checkpoint inhibitor. The efficacy evaluation indicated stability, and no severe adverse effects were observed at the time of writing. The patient's survival time was 16 months. [ABSTRACT FROM AUTHOR]

The energy inside the Earth can not only be released outward through earthquakes and volcanoes but also can be used by humans in the form of geothermal energy. Is there a correlation between different forms of energy release? In this contribution, we perform detailed seismic and geothermal research in the Beijing area. The results show that the geothermal resources in Beijing belong to typical medium-low temperature geothermal resources of the sedimentary basin, and some areas are controlled by deep fault activities (e.g., Xiji geothermal well (No. 17)). The heat sources are upper mantle heat, radioactive heat in granite, and residual heat from magma cooling. The high overlap of earthquakes and geothermal field locations and the positive correlation between the injection water and earthquakes indicate that the exploitation and injection water will promote the release of the earth's energy. The energy releases are partitioned into multiple microearthquakes, avoiding damaging earthquakes (ML ≥ 5) due to excessive energy accumulation. Therefore, the exploitation of geothermal resources may be one way to reduce destructive earthquakes. Furthermore, the use of geothermal resources can also reduce the burning of fossil energy, which is of great significance in dealing with global warming. [ABSTRACT FROM AUTHOR]