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Spark plasma sintering (SPS) is an ultrafast sintering method for the preparation of ceramics and ceramic composites with simple geometrical shapes, with the combined application of uniaxial pressure. This study aims to propose an SPS densification method for Si3N4 ceramic balls without necessitating alterations to tools and equipment. The Si3N4 ceramic balls intended for sintering are positioned within a SiC powder bed inside the conventional die used in SPS. The study systematically investigates the effects of presintering temperature (1400°C, 1500°C, and 1600°C) and SPS temperature (1600°C, 1700°C, and 1800°C) on the sphericity, relative density, phase composition, microstructure, and mechanical properties of Si3N4 ceramic balls. Experimental findings reveal that Si3N4 ceramic balls exhibiting an optimal combination of sphericity (0.94 ± 0.02), relative density (98.4%), and mechanical properties (Vickers hardness: 17.5 ± 0.4 GPa, fracture toughness: 6.4 ± 0.1 MPa·m1/2) were successfully achieved at a pre‐sintering temperature and SPS temperature of 1600°C, coupled with the use of a SiC powder bed and SPS method. Consequently, the SPS method demonstrates its capability to fabricate Si3N4 ceramic balls with excellent performance. [ABSTRACT FROM AUTHOR]

The rigid guide is a crucial component of the mine hoisting system, which plays a role in guiding the smooth operation of the hoisting container in the process of mine hoisting. To address the issue of detection devices mounted on mobile equipment affecting normal production, this paper proposes to install the device inside the groove of the rigid guide, and directly collect the vibration signal of the rigid guide while the mine hoisting system is in operation. The collected vibration signals are preprocessed and subjected to fast Fourier transform. To fully extract the fault information hidden in the spectrogram, the vibration signals are transformed into a two-dimensional spectrogram in polar coordinates and used as a sample dataset for training a convolutional neural network (CNN) to achieve fault classification and identification of the rigid guide. Experimental studies on this method show that the accuracy of CNN in identifying rigid guide fault categories reaches 92.63%. Compared to the method of collecting vibration signals from mobile devices, the fault identification accuracy also exceeds 90%. By analyzing the vibration signals of the rigid guide, it is possible to determine whether there is a fault. [ABSTRACT FROM AUTHOR]

Objective This study examined the relationship between cystatin C (CysC) levels and all-cause, cardiovascular disease (CVD), and cancer mortality in US metabolic syndrome (MetS) patients. Methods The 1999-2002 National Health and Nutrition Examination Survey (NHANES) prospective cohort research included 1980 MetS participants. To assess CysC levels and all-cause, CVD, and cancer mortality, fitted curves, Kaplan-Meier survival curves, Cox regression analysis, and receiver operating characteristic curves were performed. Results During a mean follow-up of 15.3 ± 5.4 years, a total of 819 deaths occurred. The fitted and Kaplan-Meier survival curves revealed that greater CysC levels were linked to higher all-cause, CVD, and cancer mortality rates (P <.05). After adjusting for variables, CysC level was associated with all-cause, CVD, and cancer mortality at 1.63 (1.42-1.88), 1.53 (1.19-1.95), and 1.53 (1 ∼ 2.32), respectively (P <.05). Tertile models showed consistent results: high CysC Tertile participants showed higher risk of all-cause mortality (HR 1.87; 1.43-2.45), CVD mortality (HR 1.97, 1.15 ∼ 3.38), and cancer mortality (HR 1.72, 1.01 ∼ 2.91) compared to those in the lowest tertile (P <.05). Subgroup studies by sex and other characteristics confirmed the findings. CysC demonstrated the higher predictive efficacy across mortality outcomes, followed by eGFR, outperforming urea nitrogen, creatinine, uric acid, and C-reactive protein. CysC alone exhibited substantial predictive value for all-cause (AUC 0.773; P <.05) and CVD mortality (AUC 0.726; P <.05). Combining CysC with age enhanced predictive value for all-cause mortality to 0.861 and CVD mortality to 0.771 (P <.05). Conclusion MetS patients with elevated CysC levels have a higher risk of all-cause, CVD, and cancer death. CysC may predict MetS all-cause and CVD mortality. [ABSTRACT FROM AUTHOR]

To improve the detection accuracy of vehicles and pedestrians in traffic scenes using object detection algorithms, this paper presents modifications, compression, and deployment of the single-stage typical algorithm YOLOv7-tiny. In the model improvement section: firstly, to address the problem of small object missed detection, shallower feature layer information is incorporated into the original feature fusion branch, forming a four-scale detection head; secondly, a Multi-Stage Feature Fusion (MSFF) module is proposed to fully integrate shallow, middle, and deep feature information to extract more comprehensive small object information. In the model compression section: the Layer-Adaptive Magnitude-based Pruning (LAMP) algorithm and the Torch-Pruning library are combined, setting different pruning rates for the improved model. In the model deployment section: the V7-tiny-P2-MSFF model, pruned by 45% using LAMP, is deployed on the embedded platform NVIDIA Jetson AGX Xavier. Experimental results show that the improved and pruned model achieves a 12.3% increase in mAP@0.5 compared to the original model, with parameter volume, computation volume, and model size reduced by 76.74%, 7.57%, and 70.94%, respectively. Moreover, the inference speed of a single image for the pruned and quantized model deployed on Xavier is 9.5 ms. [ABSTRACT FROM AUTHOR]

In this paper, we estimate the oscillation of harmonic functions on the (N − 1)-dimensional Sierpiński gasket KN, where K3 is the classical Sierpiński gasket. By using this result, we prove that both the box dimension and the Hausdorff dimension of graphs of harmonic functions on KN are log2N. [ABSTRACT FROM AUTHOR]

Aim: To synthesize available evidence about core competencies for nurses engaged in palliative care. Design: A scoping review conducted according to the framework from Joanna Briggs Institute. Methods: The Preferred Reporting Items for Systematic Reviews and Meta‐Analyses extension for Scoping Reviews checklist was adopted to report this scoping review. The PubMed, Web of Science, Embase, ScienceDriect, CNKI, WangFang, VIP and Sinomed databases were used to systematically search for published studies from their inception to December 2023. Two researchers independently screened and selected relevant studies and performed the data charting. Results: Twenty‐six studies were included in this scoping review. Among these, 14 studies identified core competency assessment instruments among nurses engaged in palliative care, with the Palliative Care Core Competence Questionnaire was used most frequently; 13 studies investigated the status of core competencies of nurses engaged in palliative care, the majority of included studies indicated that nurse's core competencies were at moderate levels; 11 studies explored the factors influencing the core competencies of the nurses engaged in palliative care, which were classified as sociodemographic‐related factors, palliative care education‐related factors, death attitude, palliative care practice‐related experience and others. Conclusion: This scoping review offers a comprehensive overview of the current landscape of core competencies among nurses in palliative care. Findings suggested that the clinical nursing leaders need to develop tailored strategies and interventions to address specific factors and promote the continuous development of nurses' competencies in palliative care. Relevance to Clinical Practice: Core competency assessment instruments equip nurses and healthcare organizations with a range of validated tools for evaluating their proficiency in palliative care. Targeted core competency enhancement programmes need to be developed to foster a nursing workforce better equipped to improve the quality of life of end‐of‐life patients and their families. Patient or Public Contribution: No patient or public contribution. [ABSTRACT FROM AUTHOR]

In-depth understanding of the layer-by-layer process is critical for the quality control of additive manufactured (AM) components. Besides the development of experimental techniques, computational modelling is another important way to study the AM mechanisms in detail. However, currently there is still lack of a modelling platform that integrates all the necessary physics involved in the AM process. In the present study, we develop a modelling framework that integrates a phase field method for microstructure evolution, a lattice Boltzmann method for melt pool dynamics, a modified ray-tracing method for laser-material interaction, and a minimum gravity energy algorithm for powder bed generation to simulate the single-track, powder bed fusion (PBF) process of NiTi shape memory alloy. Our simulation shows that different from keyhole depth, melt pool size does not obey the scaling law with line energy density, the keyhole depth and the overlapping ratio of laser spot vs. keyhole opening together determine the laser absorptivity. Based on the simulation finding, we also develop a self-consistent analytical model to predict the keyhole depth and the absorptivity for given scanning parameters. The present work lays a solid foundation towards quantitative understanding of multi-layer AM process.

BackgroundPapillary Renal Neoplasm (PRN) with polarity inversion is a less common subtype of kidney cancer with an apparently recognizable morphology, distinct immunohistochemical profiles, and frequent KRAS mutations. It has been estimated to account 4% of previously diagnosed PRN.Case presentationThis is a retrospective case report of two patients diagnosed with PRNRP. Two males were found to have kidney mass accidentally through imaging examination in clinic. Both of the patients had no obvious discomfort and abnormal test indicators. Subsequently, they underwent partial nephrectomy in our center by the same surgeon and followed up closely with an impressive clinical outcome. The pathology reports indicated that their pathological features were consistent with PRNRP. The HE staining showed a monolayer of papillary or tubular structures, with small nuclei away from the cytoplasmic top of the basement membrane. The immunohistochemical results were GATA3 (+), vimentin (-).ConclusionOur case reports and literature review suggested that PRNRP should be separated from traditional PRN and partial nephrectomy is a robust modality for PRNRP. The morphological, immunohistochemical, and genetic information of the cases we presented would provide important material for PRNRP to become a distinct category with benign clinical outcome.