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As the turbine inlet temperatures of aero engines continue to rise， there is an urgent need to develop a new generation of single-crystal superalloys and their thermal protective coatings for turbine blades. In order to meet the stringent requirements for the comprehensive performance of high-temperature structural materials in the complex service environments of aero engines， the intelligent design research of single crystal superalloys and thermal protection coatings has been gradually carried out at home and abroad in recent years under the promotion of material integrated computational engineering and material informatics. This paper reviews the latest research progress in the design of novel single-crystal superalloys and thermal protective coatings by utilizing multi-scale computational simulations and machine learning methods. The findings confirm that multi-scale computational simulations offer robust theoretical support for understanding the strengthening and toughening mechanisms of single-crystal superalloys， as well as the oxidation resistance and diffusion protective mechanisms of thermal protective coatings. Additionally， the study highlights the reliability and significant potential of machine learning in constructing intrinsic "composition-structure-property" relationship for high-temperature structural materials. This approach paves an intelligent and efficient new pathway for the rapid development of next-generation high-temperature single-crystal superalloys and thermal protective coatings.

With the global energy transition and increasing environmental requirements，hydrogen-mixed gas turbines as a high-efficiency and low-emission energy conversion equipment has been widely concerned. This paper reviews the development status of hydrogen-mixed gas turbines domestically and internationally，analyzes the characteristics of hydrogen combustion in gas turbines，explores the impact of hydrogen combustion on complex components and the application of high-temperature materials，and analyzes the performance requirements for hot-end component materials operating under high temperature，high pressure，and corrosive conditions，as well as the main challenges and potential solutions in current material development. The effects of water vapor and hydrogen embrittlement during hydrogen combustion on gas turbine alloys and thermal barrier coatings are discussed in detail.Water vapor accelerates the oxidation and corrosion of alloys，leading to a decline in mechanical properties. Furthermore，hydrogen embrittlement significantly affects the toughness and durability of alloys，increasing the risk of crack propagation and fracture. In terms of the problems，future research should focus on multi-field coupling simulations and accelerated corrosion tests，considering the factors such as temperature，pressure，and different atmospheres to establish realistic environment simulators to evaluate alloy and coating performances. Additionally，the combined effects of hydrogen and water vapor on high-temperature alloys and thermal barrier coatings should be emphasized. This includes investigating the diffusion mechanisms of hydrogen in alloys，interactions with lattice defects，and the microscopic processes leading to hydrogen embrittlement. Building oxidation models in high-temperature water vapor environments，clarifying the dissociation and adsorption mechanisms of water vapor at high temperatures，the hydroxylation of protective oxide films Al2O3 and Cr2O3，and the growth behavior of non-protective oxides（e.g.，spinel） are also essential.

The thin-wall effect of single crystal superalloys refers to the phenomenon that when the thickness of the sample and the part is less than 1 mm，the lasting life is reduced， the creep rate is increased and other mechanical properties are significantly attenuated. With the development of the internal cooling structure of advanced aero-engine single crystal blade parts， the structural thickness of some areas decreases， making it a typical thin-walled structure. Thus， it is of great engineering significance to consider the thin-wall effect in the thin-wall region during the design and manufacture of blades. Creep performance is one of the most important properties of superalloys for turbine blade application. This paper summarizes the thin-wall effect in creep performance of the superalloys as well as some advanced experimental equipment in the study of thin-wall effect. Research on thin-wall debit effect of superalloys can be divided into two categories，one is the cause of thin-wall debit，including the relative enhancement of oxidation，more significance in anisotropy，changes in microstructure and the initiation or growth of defects，and the factors that influence the thin-wall debit effect including experimental conditions（temperature，stress，etc.），the processing methods（casting， machining）， geometric shape （rectangular cross-section， ring cross-section， film cooling holes）. Research on thin-wall debit effect is within the scope of engineering application，as a part of “component level/analog component level” in “building block” verification and evaluation technology，thin-wall debit effect research under service environment or near-service environment conditions is more valuable for application. For this purpose，a variety of advanced experimental equipment platforms have been developed to simulate one or several coupled service conditions（high temperature，high pressure，corrosion/erosion，centrifugal loading） of the blade in the engine. Future research on thin-wall effects should be carried out under conditions closer to actual service conditions by preparing specimens according to the actual blade manufacturing process and conducting experiments on the equipment that simulates the service environment.

Abstract Background COVID-19-related stigmatization refers to COVID-19-related judgements by others that devalue the individual. Such stigmatization towards healthcare workers may cause psychological burden and negative consequences. Such stigmatization may have particularly overwhelmed allied health trainees (AHTs) and post-graduate year doctors (PGYDs) because they just started their medical career. Social support and resource support have been reported to benefit psychological health and reduce stigmatization. Therefore, the present study used a cross-sectional study design to investigate the association between perceived stigma, self-stigma, psychological distress, and negative outcomes (including emotional exhaustion, insomnia and suicidal ideation) among AHTs and PGYDs in Taiwan. Methods An online survey distributed between July and December, 2022 received 522 responses. Variables were assessed using the 21-item Depression, Anxiety and Stress Scale, Insomnia Severity Index and a series of self-designed questions to assess social support, resource support, perceived stigma, self-stigma, emotional exhaustion, and suicidal ideation. Results Structural equation modeling showed that perceived stigma was associated with self-stigma (standardized coefficient [β] = 0.428, p

BackgroundPostherpetic itch (PHI) is an easily overlooked complication of herpes zoster that greatly affects patients' quality of life. Studies have shown that early intervention can reduce the occurrence of itch. The aim of this study was to develop and validate a predictive model through a machine learning approach to identify patients at risk of developing PHI among patients with herpes zoster, making PHI prevention a viable clinical option.MethodWe conducted a retrospective review of 488 hospitalized patients with herpes zoster at The First Affiliated Hospital of Zhejiang Chinese Medical University and classified according to whether they had PHI. Fifty indicators of these participants were collected as potential input features for the model. Features associated with PHI were identified for inclusion in the model using the least absolute shrinkage selection operator (LASSO). Divide all the data into five pieces, and then use each piece as a verification set and the others as a training set for training and verification, this process is repeated 100 times. Five models, logistic regression, random forest (RF), k-nearest neighbor, gradient boosting decision tree and neural network, were built in the training set using machine learning methods, and the performance of these models was evaluated in the test set.ResultsSeven non-zero characteristic variables from the Lasso regression results were selected for inclusion in the model, including age, moderate pain, time to recovery from rash, diabetes, severe pain, rash on the head and face, and basophil ratio. The RF model performs better than other models. On the test set, the AUC of the RF model is 0.84 [(95% confidence interval (CI): 0.80–0.88], an accuracy of 0.78 (95% CI: 0.69–0.86), a precision of 0.61 (95% CI: 0.45–0.77), a recall of 0.73 (95% CI: 0.58–0.89), and a specificity of 0.79 (95% CI: 0.70–0.89).ConclusionsIn this study, five machine learning methods were used to build postherpetic itch risk prediction models by analyzing historical case data, and the optimal model was selected through comparative analysis, with the random forest model being the top performing model.

Abstract Real‐time tracking of drug release from nanomedicine in vivo is crucial for optimizing its therapeutic efficacy in clinical settings, particularly in dosage control and determining the optimal therapeutic window. However, most current real‐time tracking systems require a tedious synthesis and purification process. Herein, a supramolecular nano‐tracker (SNT) capable of real‐time tracking of drug release in vivo based on non‐covalent host‐guest interactions is presented. By integrating multiple cavities into a single nanoparticle, SNT achieves co‐loading of drugs and probes while efficiently quenching the photophysical properties of the probe through host‐guest complexation. Moreover, SNT is readily degraded under hypoxic tumor tissues, leading to the simultaneous release of drugs and probes and the fluorescence recovery of probes. With this spatial and temporal consistency in drug loading and fluorescence quenching, as well as drug release and fluorescence recovery, SNT successfully achieves real‐time tracking of drug release in vivo (Pearson r = 0.9166, R2 = 0.8247). Furthermore, the released drugs can synergize effectively with fluorescent probes upon light irradiation, achieving potent chemo‐photodynamic combination therapy in 4T1‐bearing mice with a significantly improved survival rate (33%), providing a potential platform to significantly advance the development of nanomedicine and achieve optimal therapeutic effects in the clinic.

Sexual dimorphism in vocal signals is found across many bird species. By evaluating correlations among sex, behaviors, and vocalizations, the meaning and utility of sound production may be inferred. Anna's hummingbirds Calypte anna exhibit pronounced sexual dimorphism, with males being larger and having more vibrant coloration than females, but vocal dimorphism in the species is less studied. A common vocalization of Anna's hummingbirds is the chip note, which is produced by both sexes in a wide array of contexts. Here, we correlated temporal parameters of recorded chip notes with individual sex and behavioral contexts gathered from field observations. The production rate of chip notes differed significantly between male and female hummingbirds but did not vary much with behavioral context. Although Anna's hummingbirds produce chips across a broad spectrum of behaviors, dimorphic chip production may be especially important in territorial behavior.

Objective Surgical treatment with internal fixation, specifically percutaneous fixation with three cannulated compression screws (CCSs), is the preferred choice for young and middle‐aged patients. The mechanical advantage of the optimal spatial configuration with three screws provides maximum dispersion and cortical support. We suspect that the spatial proportion of the oblique triangle configuration (OTC) in the cross‐section of the femoral neck isthmus (FNI) may significantly improve shear and fatigue resistance of the fixed structure, thereby stabilizing the internal fixation system in femoral neck fracture (FNF). This study aims to explore the mechanical features of OTC and provide a mechanical basis for its clinical application. Methods Twenty Sawbone femurs were prepared as Pauwels type III FNF models and divided equally into two fixation groups: OTC and inverted equilateral triangle configuration (IETC). Three 7.3 mm diameter cannulated compression screws (CCSs) were used for fixation. The specimens of FNF after screw internal fixation were subjected to static loading and cyclic loading tests, respectively, with five specimens for each test. Axial stiffness, 5 mm failure load, ultimate load, shear displacement, and frontal rotational angle of two fragments were evaluated. In the cyclic loading test, the load sizes were 700 N, 1400 N, and 2100 N, respectively, and the fracture end displacement was recorded. Results were presented as means ± SD. Data with normal distributions were compared by the Student's t test. Results In the static loading test, the axial stiffness, ultimate load, shear displacement, and frontal rotational angle of two fragments were (738.64 vs. 620.74) N/mm, (2957.61 vs. 2643.06) N, (4.67 vs. 5.39) mm, and (4.01 vs. 5.52)° (p 0.05). Conclusion When three CCSs are inserted in parallel to fix FNF, the OTC of three screws has obvious biomechanical advantages, especially in shear resistance and early postoperative weight‐bearing, which provides a mechanical basis for clinical selection of ideal spatial configuration for unstable FNF.

Abstract The Orthopoxvirus genus, especially variola virus (VARV), monkeypox virus (MPXV), remains a significant public health threat worldwide. The development of therapeutic antibodies against orthopoxviruses is largely hampered by the high cost of antibody engineering and manufacturing processes. mRNA-encoded antibodies have emerged as a powerful and universal platform for rapid antibody production. Herein, by using the established lipid nanoparticle (LNP)-encapsulated mRNA platform, we constructed four mRNA combinations that encode monoclonal antibodies with broad neutralization activities against orthopoxviruses. In vivo characterization demonstrated that a single intravenous injection of each LNP-encapsulated mRNA antibody in mice resulted in the rapid production of neutralizing antibodies. More importantly, mRNA antibody treatments showed significant protection from weight loss and mortality in the vaccinia virus (VACV) lethal challenge mouse model, and a unique mRNA antibody cocktail, Mix2a, exhibited superior in vivo protection by targeting both intracellular mature virus (IMV)-form and extracellular enveloped virus (EEV)-form viruses. In summary, our results demonstrate the proof-of-concept production of orthopoxvirus antibodies via the LNP-mRNA platform, highlighting the great potential of tailored mRNA antibody combinations as a universal strategy to combat orthopoxvirus as well as other emerging viruses.

Abstract RNA-binding proteins (RBPs) are kinds of proteins with either singular or multiple RNA-binding domains (RBDs), and they can assembly into ribonucleic acid–protein complexes, which mediate transportation, editing, splicing, stabilization, translational efficiency, or epigenetic modifications of their binding RNA partners, and thereby modulate various physiological and pathological processes. CUG-BP, Elav-like family 1 (CELF1) is a member of the CELF family of RBPs with high affinity to the GU-rich elements in mRNA, and thus exerting control over critical processes including mRNA splicing, translation, and decay. Mounting studies support that CELF1 is correlated with occurrence, genesis and development and represents a potential therapeutical target for these malignant diseases. Herein, we present the structure and function of CELF1, outline its role and regulatory mechanisms in varieties of homeostasis and diseases, summarize the identified CELF1 regulators and their structure–activity relationships, and prospect the current challenges and their solutions during studies on CELF1 functions and corresponding drug discovery, which will facilitate the establishment of a targeted regulatory network for CELF1 in diseases and advance CELF1 as a potential drug target for disease therapy. Graphical Abstract

Background: This study compared the efficacy of oropharyngeal airways (OA) and nasopharyngeal airways (NA) in maintaining oxygenation during painless fiberoptic bronchoscopy (PFB) in patients sedated with remimazolam besylate. Methods: Two hundred and fifty-two patients were randomized to the OA or NA group. Remimazolam besylate was used for anesthesia induction and maintenance in both groups. We measured and recorded several physiological parameters, including mean arterial pressure, heart rate and oxygen saturation (SpO2), at various time points: before anesthesia (T1), after anesthesia induction (T2), immediately after the bronchoscope reached the trachea (T3), during the procedure (T4), and 5 min after transfer to the post-anesthesia care unit (T5). The incidence and frequency of hypoxemia, minimum SpO2 during the procedure and patient awakening time after flumazenil administration were also recorded. Additionally, the relationship between minimum SpO2 and body mass index (BMI) was investigated. Results: Patients in the NA group experienced a higher incidence of hypoxemia compared to the OA group. Patients in the OA group maintained higher SpO2 levels at T3 and had a higher minimum SpO2 during the procedure than the NA group. Furthermore, a significant negative correlation was observed between minimum SpO2 and BMI. Following flumazenil anesthesia reversal, nearly 97 % of patients awakened within 1 min. Conclusions: This study suggests that OA may provide a better safety profile than NA by preserving respiratory function during PFB.