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A population spatialization method based on the integration of feature selection and an improved random forest model
Ascertaining the precise and accurate spatial distribution of population is essential in conducting effective urban planning, resource allocation, and emergency rescue planning. The random forest (RF) model is widely used in population spatialization studies. However, the complexity of population distribution characteristics and the limitations of the RF model in processing unbalanced datasets affect population prediction accuracy. To address these issues, a population spatialization model that integrates feature selection with an improved random forest is proposed herein. Firstly, recursive feature elimination using cross validation (RFECV), maximum information coefficient (MIC), and mean decrease accuracy (MDA) methods were utilized to select population distribution feature factors. The random forest was constructed using feature subsets that were selected via different feature selection methods, namely MIC-RF, RFECV-RF and MDA-RF. Subsequently, the feature factors corresponding to the model with the highest accuracy were selected as the optimal feature subsets and used in the model construction as input data. Additionally, considering the imbalanced in population spatial distribution, we used the K-means ++ clustering algorithm to cluster the optimal feature subset, and we used the bootstrap sampling method to extract the same amount of data from each cluster and fuse it with the training subset to build an improved random forest model. Based on this model, a spatial population distribution dataset of the Southern Sichuan Economic Zone at a 500m resolution was generated. Finally, the population dataset generated in this study was compared and validated with the WorldPop dataset. The results showed that utilizing feature selection methods improves model accuracy to varying degrees compared with RF based on all factors, and the MDA-RF had the lowest MAPE of 0.174 and the highest R2 of 0.913 among them. Therefore, feature factors selection using the MDA method was considered the optimal feature subset. Compared with MDA-RF, the prediction accuracy of the improved RF built on the same subset increased by 1.7%, indicating that improving the bootstrap sampling of random forest by using the K-means++ clustering algorithm can enhance model accuracy to some extent. Compared with the WorldPop dataset, the accuracy of the results predicted using the proposed method was enhanced. The MRE and RMSE of the WorldPop dataset were 57.24 and 23174.98, respectively, while the MRE and RMSE of the proposed method were 25.00 and 15776.50, respectively. This implies that the method proposed in this paper could simulate population spatial distribution more accurately.
Investigation of interface characteristics and mechanical performances of Cu/Al plate fabricated by underwater explosive welding method
Cu/Al composite plate was manufactured by underwater explosive welding method. The interface characteristics and mechanical properties of Cu/Al composite plate were evaluated and analyzed through phased array ultrasonic inspection, microstructure, uniaxial tensile test, three-point bending test, tensile shearing test and microhardness test. The results showed that the welding of thin Cu and Al plates is achieved by underwater explosive welding, with a Cu plate thickness of only 0.5 mm. A well bonded interface between Cu and Al plate is obtained, at a detonation velocity of 4 000 m/s, when the distance between Cu foil and Al plate is 0.2 mm. There are wavy fusion zones at the bonding interface of Cu/Al composite plate. No delamination or cracks are found at the bonding interface between Cu and Al during tensile and bending tests, and local cracking only occurs at the necking part in the tensile test due to severe deformation. The tensile strength and minimum tensile shearing strength of Cu/Al composite plate reaches 133 and 72.9 MPa, respectively. The hardness values of fusion zone, Cu and Al at the interface reach 385, 135 and 52 HV, respectively. The increase in hardness of Cu and Al near the interface is mainly caused by severed deformation induced by intense shock pressure.
TENS improves CFL injury rat and regulates the intestinal microbiota
Aim This study revealed the mechanism of transcutaneous electrical nerve stimulation (TENS) for improving the calcaneofibular ligament (CFL) injury rats by regulating the intestinal microbiota. Methods After 1, 2, and 3 weeks of TENS treatment, the improvement of CFL injury rats model and the expressions of IL-1β/NF-κB/IL-17 signaling pathway were measured. Then the intestinal microbiota was analyzed by 16S rDNA sequencing and its functions related to improve CFL injury rat were analyzed. Results TENS could improved the athletic ability of CFL injury rats and reduced the expressions of IL-1β/NF-κB by regulating the IL-17 signaling pathway. By 16S rDNA sequencing analysis, the TENS treatment improved the intestinal dysbacteriosisof CFL injury rats and decrease pathogenic bacteria Ruminococcus and Dubosiella. The changed intestinal microbiota maybe relative with the ankle injury, whereas the increase in probiotics (Bacteroides and Lactobacillus) was relative with anti-inflammation. Conclusion TENS could down-regulate the expressions of IL-1β/NF-κB to improve CFL injury rat. TENS could change the intestinal microbiota of CFL rats and the changed bacteria whose function related to anti-inflammation could improve CFL rat. The intestinal microbiota could become a potential treatment for CFL injury.
Current status and influencing factors of nurses’ work engagement in Chinese tertiary hospitals: A latent profile analysis
Background Work engagement is a work-related state of mind full of positivity and vigor. Understanding the current status and influencing factors of nurses’ work engagement is essential for improving the quality of nursing services and stabilizing the nursing workforce building. This study aimed to explore the potential categories of nurses’ work engagement and their influencing factors and provide a reference basis for developing targeted interventions to improve their work engagement. Methods From March to April 2024, 1,919 nurses from 12 tertiary hospitals in Sichuan Province, China, were enrolled in the study using convenience sampling. A demographic profile questionnaire, work engagement scale, and professional mission scale were used to investigate them. Latent profile analysis was used to explore the categories of nurses’ work engagement, and unordered multicategorical logistic regression was used to analyze the influencing factors of each category. Results Nurses’ work engagement could be categorized into three potential profiles: low work engagement group (n = 659, 34.3%), medium work engagement group (n = 763, 39.8%), and high work engagement group (n = 497, 25.9%). The unordered multi-categorical logistic regression results showed that marital status, reasons for choosing a nursing specialty, self-rated sleep quality, current work intensity, and sense of professional mission were influential factors affecting the potential profile of work engagement among nurses in tertiary care hospitals. Among them, unmarried nurses were more likely to belong to the low work engagement group; those who chose nursing specialties based on personal interest were more likely to belong to the medium work engagement group; those with medium work intensity were more likely to belong to the high work engagement group; and those with good self-assessed sleep quality and higher scores of sense of professional mission were more likely to belong to the medium and high work engagement groups. Conclusion The potential profiles of nurses’ work engagement in Chinese tertiary hospitals were dominated by the medium and low work engagement groups, with significant heterogeneity. Nursing managers should tailor interventions to enhance nurses’ sense of professional mission according to the characteristics of each type of nurse work engagement, thereby improving work engagement and nursing service quality.
Light wins uphill battle to solve enduring problem in organic synthesis
The existing characteristics, transport patterns, and significance of nanoparticulate pollutants in groundwater surrounding an industrial park
Nanoparticles, increasingly recognized by regulators and the public, have become potential pollutants in various media, including water. Water security, a pressing global issue, is exacerbated by industrialization, with industrial wastewater being a significant contributor to water pollution. This study collected nanoparticles from groundwater samples in residential areas surrounding the Mingzhu Industrial Park in Guangdong Province, China. To understand their characteristics as potential pollutants in wastewater and the information they provide, field emission transmission electron microscopy (TEM) was used to analyze the composition, elemental content, morphology, and crystal structure of the nanoparticles. The nanoparticles originated from three sources: factories, water pipes, and the natural environment. They aggregate and oxidize during transport, ensuring their stability in water. This study elucidates the characteristics and transport patterns of particulate pollutants in groundwater near industrial parks, a prerequisite for assessing the hazards of nano-pollutants in natural environments. Additionally, it provides valuable insights for future discussions on their ecological impacts and advancements in water detection and treatment technologies.
Influencing factors of HCV testing willingness among men who have sex with men in China: A structural equation modeling analysis
Background Men who have sex with men (MSM) are a population with greater likelihood of the hepatitis C virus (HCV). Early detection of HCV status is beneficial to therapy and prevention of the further transmit of HCV. The testing rate of HCV in MSM is low, so it is important to investigate the factors that influence testing willingness in order to increase the testing rate. Objectives Based on the health belief model (HBM), this study investigated the influencing factors of HCV testing willingness among MSM, and provided a basis for promoting HCV testing among MSM. Methods Non-probability sampling was employed to collect samples, and electronic questionnaires were used to perform cross-sectional surveys on the samples, including socio-demographic characteristics, sexual behavior characteristics, HCV testing willingness and HBM scale. The data was evaluated with a structural equation model (SEM). Results Result of the 857 MSM, 55.7% had ever undergone HCV testing, 90.9% were willing to undergo HCV testing in the future, and 71.7% were anticipated to undergo HCV testing within the next six months. The SEM's findings demonstrated that behavioral intention was positively impacted by self-efficacy (β = 0.482, p < 0.001) and perceived susceptibility (β = 0.312, p < 0.001), while behavioral intention was negatively impacted by perceived barriers (β = -0.254, p < 0.001). Furthermore, behavioral intention was indirectly impacted by perceived benefits (β = 0.309, p < 0.001) and perceived barriers (β = -0.139, p < 0.001), with self-efficacy acting as a mediating factor. Conclusion Self-efficacy, perceived susceptibility, benefits, and barriers predict behavioral intention. These findings can inform the development of methods to increase MSM willingness to identify HCV.
A hierarchical trait and state model for decoding dyadic social interactions
Using an analytic rubric system for the evaluation of anterior ceramic crown preparation performed by preclinical dental students
Background This study aimed to assess the performance of preclinical dental male and female students in performing maxillary anterior all-ceramic preparations using a validated analytic rubric system. Methods An analytical rubric for the assessment of maxillary anterior ceramic preparations was used in a preclinical phase study with two evaluators. The grading was based on a 4-point scale for all steps for crown preparation, and the total score was calculated out of 40 points. Differences in rubric parameter scores between male and female students were analyzed via an independent t test. Other tests, such as the kappa test and Pearson’s correlation coefficient, were used to measure the associations among grade point average (GPA), evaluators, and gender participants, with p < 0.050 considered a cutoff point for statistical significance. Results The study revealed that students of both genders demonstrated high performance, with females scoring a mean of 37.70 ± 1.61 (SD) and males scoring a mean of 36.50 ± 2.36 (SD). A significant difference in the average overall score was recorded by both evaluators (p = 0.034). The highest value was for intact gingival margins and surrounding tissues (3.89 ± 0.31 males, 3.92 ± 0.28 females), and the lowest value was for axial wall reduction (3.50 ± 0.36 males, 3.62 ± 0.42 females). Among the different parameters, only the finish line form parameter was significantly different (p = 0.011), as found by evaluator 1. Inter-rater reliability analysis revealed varying levels of agreement between the evaluators. Strong positive correlations were found between several rubric parameters, but students’ GPA had a weak, nonsignificant correlation with their preclinical performance (p = 0.495). Conclusion The analytic rubric revealed minor gender differences in preclinical performance, with female students performing slightly better. The rubric demonstrated varying inter-rater reliability and positive correlations across parameters. However, GPA showed limited correlation with preclinical performance.
Fabrication of aluminum-coated glucose/graphene oxide hybrid materials for the dual adsorption of fluoride and methylene blue
Interface agent modified by ternary polymers for ceramic tile of old walls based on grey relational analysis
The Interface Agent for Old Wall Tiles (IAWT) is an environmentally friendly material. However, its application in engineering is limited by its tendency to lose adhesion under harsh conditions. Factors such as freeze-thaw cycles, wind vibrations, rainfall, and thermal stress negatively affect the bond strength of IAWT. This study investigated the effects of PTB emulsion on various properties of IAWT, including bond strength, freeze-thaw resistance, wind vibration resistance, compressive-flexural ratio, water absorption, and microstructure. Orthogonal experiments were conducted to examine the impact of three key factors on the macroscopic properties of IAWT. The results indicated that increasing the ratio of PTB emulsion to water (P/W) improved bond strength under normal environmental conditions and enhanced freeze-thaw and wind vibration resistance. Furthermore, a higher P/W ratio reduced both the compressive-flexural ratio and water absorption. The addition of PTB emulsion slowed the hydration reaction, increased the number of micropores, and reduced the cumulative pore volume. Furthermore, it enhances the bond strength between the coating and the base layer, thereby increasing the durability of the renovation project for old walls. These enhancements yield positive economic and environmental benefits.
Local field potential changes during euthanasia may parallel with near death experience
Photoinduced copper-catalysed deracemization of alkyl halides
Depression as a risk factor for Alzheimer’s disease: A human post-mortem study
Depression is associated with persistent low mood. In mid to late life, it has been identified as a risk factor for Alzheimer’s disease (AD) with evidence that depression might be an early manifestation of AD. Although the underlying mechanisms by which depression enhances AD development remain unknown, there are several features commonly seen in both diseases such as the presence of neuroinflammation. In this study, we aimed to identify whether neuroinflammation is increased in depression as observed in the early stages of AD by examining post-mortem human brain tissue. Post-mortem human brain tissue from 54 cases with depression and 37 controls without depression were retrieved from the Douglas Bell Canada Brain Bank. Sixteen early-stage AD cases defined as a Braak stage III-IV and 15 controls were sourced from the South West Dementia Brain Bank. Frozen tissue from the dorsal prefrontal cortex was obtained for all cases in order to measure inflammatory proteins (IFN-γ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, and TNF-α) and endothelial markers (ICAM-1, VCAM) using ELISA and MesoScale Multiplex Assays. In the depression group, increase of IL-6 and IL-10, and decrease of IL-1β were observed compared to controls, with no changes detected for the other cytokines and the endothelial markers. In early-stage AD cases, only increased ICAM-1 expression was found compared to controls, indicating endothelial activation as an early feature of AD. None of the cytokines measured showed alteration of their expression in early-stage AD cases. Depression, but not AD, was associated with evidence of neuroinflammation. Depression may increase AD risk through different mechanism(s) than inflammation.
Is the solution composition and external magnetic field influencing FeNi film deposition – physicochemical and tribological studies
Abstract The iron-nickel films were deposited on the two metallic substrates (Cu, CuZn) from a mixture of iron and nickel salts and in the external magnetic field (EMF) presence. The films were electrodeposited in the fixed value of an electric current density and the time conditions. The EMF orientation and the electrochemical bath composition—molar ratio of Fe:Ni were changeable, parallel or perpendicular, and 1:1 or 1:2, respectively. Examined layers present variable surface morphologies and compositions depending on the substrates and the presence or absence of the EMF. Layers quality was analyzed using: scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. Tribo-mechanical properties (roughness, wear tracks) were registered using a confocal laser scanning microscope. The observed results show that a variation in the surface morphology and the alloy composition is related to the electrolyte composition (Fe:Ni ratio) and the presence or absence of EMF. Higher Fe content in the electrolyte (Fe:Ni, 1:1) causes more significant anomalous deposition and an increase of tribo-mechanical parameters. The tribological parameters (S sk , S ku , COF) depend on the electrolyte composition and substrate’s properties as a result of the film’s growth condition. The reduction in the thickness of the deposited layer (both electrolyte’s ratios) after applying an external magnetic field is the result of the increase of roughness parameters.
Techno-economic assessment of effervescent tablet-based nanofluids
The techno-economics of producing effervescent tablet-based nanofluids in start-up industries was investigated. The thermophysical properties, equipment costs, consumables, and operational expenditures for the production methods were determined. Electrical costs for running the devices were assessed based on the lowest, average, and highest prices worldwide. Key financial metrics, including accumulated project cost, interest, annual cost, operating expenses, production cost, payback and discounted payback periods, and internal rate of return (IRR) were calculated for different interest rates and amounts of sold products. The thermal performance under laminar and turbulent flow conditions and cost effectiveness were determined. The results showed that the effervescent tablet-based nanofluid was more favourable than its conventional counterpart. This is because of the lower equipment cost for the effervescent tablet process compared to its counterpart. The interest rate showed significant influence on the annual and product costs for both types of projects. Electrical cost had a minimal impact on the previous costs for both project cases. In addition, the effervescent tablet-based project outperformed its counterpart in terms of payback period, discounted payback period, IRR, and thermal performance, making it an optimal choice for investors and decision-makers.