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Background: The incidence of atelectasis is high in patients undergoing general anesthesia. This may cause oxygenation impairment and further contribute to postoperative pulmonary complications (PPCs). As important airway management devices for general anesthesia, few studies have compared the effects of laryngeal mask airway (LMA) and endotracheal tube (ETT) on atelectasis. Additionally, lung ultrasound has been increasingly used for bedside atelectasis diagnosis. For the above considerations, this trial is designed to compare the effects of LMA and ETT on atelectasis assessed by lung ultrasound scores, further providing more powerful clinical evidence for perioperative respiratory management of non-laparoscopic elective lower abdominal surgery under general anesthesia. Methods: This is a prospective, single-center, single-blind, randomized controlled trial. From July 2021 to July 2022, 180 patients undergoing elective non-laparoscopic lower abdominal surgery under general anesthesia will be recruited and randomly divided into the ETT and LMA groups at a ratio of 1:1. The primary outcome is the total atelectasis LUS of 12 lung regions 15 min after the establishment of the artificial airway. The total atelectasis LUS at the end of surgery and 30 min after extubation, oxygenation index, postoperative airway complications, PPCs, and length of stay will be analyzed as secondary indicators. Trial registration: ClinicalTrials.gov identifier: ChiCTR1900020818. Registered on January 20, 2019. Registered with the name of "Laryngeal mask airway versus endotracheal tube for atelectasis." URL: https://www.chictr.org.cn/showproj.aspx?proj=35143. [ABSTRACT FROM AUTHOR]

• Hole features were extracted using machine vision technology and fractal theory. • A neural network model for laser drilling BMGs was established. • The model exhibits high accuracy and reliability in parameter prediction. • Based on the predicted parameters, high-quality microholes were obtained. It is a challenging to ensure the quality of microholes during the laser drilling of bulk metallic glasses (BMGs), where the defects such as heat-affected zones, burrs, and low smoothness are usually obtained. Based on machine vision, back-propagation neural network (BPNN), and genetic algorithm (GA) in artificial intelligence technology, a relationship model between the microhole features and laser processing parameters was proposed, so as to predict and optimize the processing parameters during the laser drilling of BMGs. Firstly, the geometric parameters and texture information of microholes were obtained using fractal theory and machine vision techniques, including the gray-level co-occurrence matrix (GLCM) algorithm, image binarization, and edge extraction. A comprehensive numerical characterization of various microhole features was conducted, providing the basis for subsequent prediction and optimization. Secondly, the previously-extracted microhole features were set as input layer, and the processing parameters were set as output layer. After proper training, the BP neural network optimization model (GABPNN), based on the genetic algorithm, was established. As compared to the original BPNN model, the GABPNN model exhibited improved performance, reducing the maximum prediction error from 4.860% to 2.285%. Thirdly, with a set of input layer parameters, the required processing parameters were predicted by the model. The predicted results were verified in experiments, where good surface quality of the laser-drilled BMG microholes with good roundness and small ablation was obtained. This shows that it is feasible to predict and optimize processing parameters by GABPNN based on feature parameters extracted by machine vision. [ABSTRACT FROM AUTHOR]

Coal-rock combination refers to the coal and rock as a whole, and the failure of the whole structure of the combination is the main cause for the instability of the deep underground engineering. In deep underground engineering, the coal-rock combination is usually under certain hydrogeological conditions, and it is prone to seepage and rheological failure instability accidents due to the long-term action of water and stress. In this study, the creep constitutive model of coal-rock combination considering the influence of moisture content was established based on the Burgers creep model. According to the experimental results of triaxial creep of rock, the relationship between the moisture content and the parameter of the Burgers creep model was derived, and the correctness of the constitutive model in this study was verified. Then, through the C++ language, the core equation of the model was modified, and the numerical calculation of the model was realized by introducing the coal-rock combination creep model considering the influence of moisture content into FLAC3D numerical simulation software. Finally, the model was used to simulate and study the creep characteristics of coal-rock combination with different moisture contents under triaxial loading. The results showed that the stress environment and moisture content have significant effects on the creep characteristics of the coal-rock combination. Under the same stress state, with the increased of moisture content, the strain rate of the coal-rock combination exhibited a non-linear rapid increase in the constant-velocity creep stage, the limit creep deformation and the instantaneous elastic deformation increased, and the viscosity coefficient was significantly decreased. For example, when the axial stress was 5 MPa and the moisture content increased from 0% to 1.5%, the strain rate increased by 44.06%, the limit creep deformation increased by 20%, the instantaneous elastic deformation increased 10.53%, and the viscosity coefficient decreased by about 50%. When the moisture content is 0%, the axial stress increased from 5 to 14 MPa, and the limit creep deformation increased nearly four times. With the increase of moisture content, this value will further expand. The research conclusions can provide a certain reference basis for the long-term stability control of surrounding rock in underground engineering affected by the water. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate and identify the effects and explore the mechanisms of pyruvate kinase M2 (PKM2) on stroke‐induced post stroke depression (PSD). Methods: Rats were separated into six different groups, including sham + saline, Stroke + saline, PSD + saline, PSD + recombinant pyruvate kinase M2 (rPKM2) (112 ng/kg), PSD + rPKM2 (224 ng/kg), and PSD + rPKM2 (224 ng/kg) + bevacizumab. Then, the body weight, sucrose preference rate, immobility time, horizontal movement, and vertical movement were determined to evaluate the effect of PKM2 on improving the depressive behavior of PSD rats. Subsequently, the proliferation of oligodendrocytes in subventricular zone (SVZ) of rats in each group was examined by western blot and immunofluorescent staining. Furthermore, the mRNA and protein expression levels of TNF‐α, IL‐6, and IL‐1β were also detected by qPCR and ELISA to verify the anti‐inflammatory effects of PKM2 on PSD rats. In addition, the protein expression levels of MDA, LDH, and NO were tested to reveal that PKM2 can reduce oxidative stress in PSD rats. The western blot and IHC assays were employed to examine the protein expression levels of VEGF, PKM2, and ERK in PSD rats. Results: In this study, the results showed that PKM2 can improve the depressive behavior and proliferation of oligodendrocytes in PSD rats. In addition, PKM2 has anti‐inflammatory and anti‐oxidative stress effects on PSD rats. Meanwhile, PKM2 activated the expression level of VEGF/MAPK/ERK pathway. Conclusion: PKM2 improves symptoms of post‐ischemic stroke depression by activating VEGF‐mediated MAPK/ERK pathway. [ABSTRACT FROM AUTHOR]

An efficient shape-stabilized phase change material (PEG/CLMS) with improved thermal properties was prepared using carbon layer-modified mesoporous silica (CLMS) as the supporter of polyethylene glycol (PEG). The CLMS was fabricated based on dopamine biomimetic modification, which is facile, environmentally friendly and easy to use. The physical properties and chemical compatibility of PEG/CLMS were studied, and the results show that after the SBA-15 was modified by carbon layer, the phase change enthalpy of PEG/CLMS-b increased from 112.0 J/g to 129.9 J/g and the thermal conductivity increased from 0.34 W/(m·K) to 0.43 W/(m·K). Moreover, the PEG/CLMS-b had favourable thermostability and thermal reliability. The carbon layer modification method reported in this paper has great potential in practical applications for thermal energy storage. The thermal property improvement method developed in this study could also be used for shape-stabilized phase change materials (ssPCMs) prepared using other carriers such as diatomite and palygorskite. Therefore, a universal method was developed to improve the thermal properties of ssPCMs in this study. [ABSTRACT FROM AUTHOR]

Ring-stiffened circular cylindrical shells are commonly used in many engineering applications. In the present study, the strength and stability characteristics of ring-stiffened circular cylindrical shells are investigated using self-organising map (SOM) technique and multivariate approaches. Stress and critical pressure analysis of ring-stiffened circular cylindrical shells under hydrostatic pressure are obtained from the design guide. Design of experiment (DOE) technique is employed for generating design samples. The information behind these design samples can be studied by the self-organising map (SOM) approach. Multivariate analysis is adopted for post- processing of SOM's results. The clustering of samples can be obtained from the codebook of SOM with the help of multivariate analysis. The samples in different clusters would have their own characteristics. The variable significance in each cluster is examined. The dimensionality reduction approach is used for finding the structure of the data set. A useful visualisation approach, parallel coordinate plot with clustering information, is proposed for visualisation of design samples. Correlations and clustering of variables are also studied by the hierarchical method. The ranking of samples is conducted by minimising the distance to an 'ideal' solution in the data set. A final compromises sample is obtained. A numerical example is provided for the illustration of the present analysis. [ABSTRACT FROM AUTHOR]

In order to investigate the equivalent complex refractive index of atmospheric aerosols near the Earth's surface, we conducted measurements in the Hefei region from March to April 2022. These measurements utilized a micro-pulse lidar, an Aethalometer, and a Portable Optical Particle Profiler. These measurements encompassed aerosol particle size distribution as well as standard meteorological parameters including temperature, humidity, atmospheric pressure, and wind speed. Subsequently, this dataset was employed to develop an optimization algorithm for retrieving the equivalent complex refractive indices of near-surface aerosols. The methodology relies on lookup tables containing data for extinction efficiency and absorption efficiency factors. It operates on the premise of aerosol property stability within a defined time frame, utilizing measured extinction and absorption coefficients as simultaneous constraints during this period to inversely derive both the real and imaginary parts of the aerosol complex refractive index. Results from the simulation analysis reveal that the newly optimized retrieval algorithm, which relies on lookup tables, exhibits reduced sensitivity to instrument errors when compared to single-point constraint algorithms. This enhancement results in a more efficient and dependable approach for retrieving the aerosol complex refractive index. Empirical inversion and simulation studies were carried out to determine the aerosol equivalent complex refractive index in the Hefei region, utilizing measured data. This inversion process yielded an average complex refractive index of 1.48-i0.017 for aerosols in the Hefei region throughout the experimental period. Correlation analysis unveiled a positive association between the real part of the aerosol complex refractive index and the single-scattering albedo (SSA), whereas the imaginary part displayed a linear negative correlation with the SSA. The mathematical relationship between the real part and the SSA is y = 0.19 x + 0.62 , and the corresponding relationship between the imaginary part and the SSA is y = − 5.3 x + 0.99 . This research offers a novel method for the retrieval of the aerosol equivalent complex refractive index. [ABSTRACT FROM AUTHOR]

Pt nanoparticle (PtNP)-modified La 0.8 Sr 0.2 MnO 3 (LSM)-sensing electrodes (SE) were developed successfully by the impregnation method for amperometric total NO X (NO and NO 2) sensors. The structure, morphology, and surface valence state of SE were characterized by thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The results showed that all SEs of the sensors were uniformly modified with PtNPs; interestingly, the size of the PtNPs increased with an increase in the modified content. Compared with pure LSM, the sensor based on 0.50 vol% Pt/LSM exhibited enhanced gas-sensing properties toward total NO X. The sensitivity improved from − 9.04 to − 18.7 μA/decade in the NO X , ranging from 50 ppm to 800 ppm. Moreover, the sensor maintained a 94% response signal after a long-term stability test, showing a stable response during the long-term thermal cycling test towards total NO X. Meanwhile, the sensor exhibited markable selectivity and consistency. The catalytic effect of Pt nanoparticles was believed to be the main reason for the enhancement of gas-sensing characteristics. • A total NO X amperometric sensor was achieved through modification with PtNPs on the La 0.8 Sr 0.2 MnO 3 sensing electrode. • PtNP agglomeration was quantified using SEM images and software. • The influence of Pt nanoparticles (PtNPs) on sensing performance was evaluated, and the sensing process was analyzed. [ABSTRACT FROM AUTHOR]

The variation trends of the cold-point tropopause (CPT) are presented using radiosonde observations from 77 stations over China during 1979–2014. The latitude regions over China from 18°N to 53°N are divided into 7 latitude zones with every 5° intervals, and the spatial areas of 18°N–53°N, 75°E–135°E are divided into 27 lattices with 5° × 10° grids. The annual-mean values of height-of-CPT (H-CPT) and temperature-of-CPT (T-CPT) are then calculated by all the available samples within each latitude and longitude bin. By using the least squares regression method, it is found that the H-CPT increases with the rate of 273 m/decade, and overall the significant cooling rate of − 0.70 K/decade for the T-CPT over the whole of China. Then, the trends and latitude distribution of H-CPT and T-CPT for each latitude zone are analyzed. The difference of H-CPT among latitude distribution characteristic is reducing year by year, and the difference of T-CPT is enlarging. The H-CPT displays a rising trend between 28°N–53°N latitude region with the positive change rates, and it has decline trend between 18°N–28°N latitude region with the negative change rates. The change rates of T-CPT are negative values for all latitude zones. At last, the nonuniform latitudinal and longitudinal distribution of long-term trends of H-CPT and T-CPT are first presented for each spatial cell. [ABSTRACT FROM AUTHOR]

Serum C-peptide exhibits various biological activities. The relationship between C-peptide and atrial cardiomyopathy remains unknown. We aimed to investigate the association between C-peptide level and atrial cardiomyopathy in nondiabetic adults. Our study enrolled 4578 participants without diagnosed diabetes from the Third National Health and Nutrition Examination Survey (NHANES III). Atrial cardiomyopathy was defined as a deep terminal negative P wave in V1 below − 100 µV (more negative), according to the electrocardiogram. The participants were categorized into low C-peptide (≤ 1.46 nmol/L) and high C-peptide (> 1.46 nmol/L) groups, according to the receiver operating characteristic analysis. Odds ratio (OR) and 95% confidence interval (CI) for the association between C-peptide level and atrial cardiomyopathy were generated using multivariate logistic regression analysis. The prevalence of atrial cardiomyopathy was higher in the high C-peptide group than in the low C-peptide group (5.62% vs. 2.31%, P < 0.001, respectively). Multivariate logistic regression analysis showed that participants in the high C-peptide group had a 3.60-fold (95% CI 1.81–6.99) higher risk of atrial cardiomyopathy than those in the low C-peptide group. Per standard deviation increase in C-peptide was linked to a 1.20-fold (95% CI 1.00–1.41) higher risk in atrial cardiomyopathy. High C-peptide level might be an independent risk factor for atrial cardiomyopathy in nondiabetic adults. [ABSTRACT FROM AUTHOR]

Background In developing countries, patients with a cardiac rhythm management device (CRMD) that has become infected cannot always afford a new device, and reuse of the infected CRMD may be appropriate. To evaluate the safety of this practice, a cohort of consecutive patients with reused pacemakers was compared with a control group. Methods A single-center cohort of consecutive patients treated from 2007 to 2012 was analyzed in a two-way noninferiority study. Patients who had infected CRMDs removed at the Cardiovascular Center of The Peking University People's Hospital were enrolled, including those who had the same CRMD reimplanted and those who had a new CRMD implanted. Results This study included 212 patients, of who 99 (study group) had the same CRMD reimplanted, and 113 (control group) had a new CRMD implanted. During a mean follow-up period of 3.52 years (interquartile range: 2.1-4.7 years), 10 patients reached the primary end point of the study (infection, unexpected battery depletion, or device malfunction), including five (5%) in the study group and five (4.3%) in the control group. Recurrent infection occurred in three patients in the study group and two patients in the control group (3.0% vs 1.7%, relative risk: 1.29, 95% confidence interval: 0.62-2.29, P = 0.561). There were no cases of unexpected battery depletion in either group. Conclusions Reuse of infected CRMDs in the same patients is noninferior to the implantation of new devices. In developing countries without full medical coverage, careful reuse of infected CRMDs can be considered. [ABSTRACT FROM AUTHOR]

Post-stroke depression (PSD) is one of the most familiar complications of stroke, which refers to stroke patients who have varying degrees of depression (lasts for >2 weeks). SET domain-containing 3 (SETD3) is a conserved histone H3 methyltransferase, and the role of SETD3 in some diseases is increasingly being explored. However, the effects of SETD3 in PSD remain unclear. In this study, the PSD rat model was firstly constructed by Endothelin-1 injection combined with chronic unpredictable mild stress, and we discovered that SETD3 expression was up-regulated in PSD rat model. Additionally, SETD3 knockdown relieved the depressive symptom of PSD. Moreover, SETD3 knockdown promoted proliferation and differentiation of neural stem cells (NSCs). Due to the critical role of vascular endothelial growth factor (VEGF) in antidepressant and SETD3 can negatively regulate VEGF, we speculated that SETD3 may regulate PSD progression through VEGF. Our results demonstrated that SETD3 knockdown up-regulated VEGF expression. Furthermore, SETD3 modulated the proliferation and differentiation of NSCs through regulating VEGF expression. In conclusion, our study indicated that up-regulation of SETD3 contributed to PSD progression in rats through negatively regulating VEGF expression. The findings of this work suggest that SETD3 may be a promising target for treating PSD in the future. • The SETD3 expression was up-regulated in PSD rat model. • SETD3 knockdown relieved the symptom of PSD. • SETD3 knockdown promoted NSCs proliferation and differentiation. • SETD3 knockdown up-regulated VEGF expression. • SETD3 modulated NSCs proliferation and differentiation through VEGF. [ABSTRACT FROM AUTHOR]

Abstract: The wave propagation approach is used to analyze the free vibration of ring-stiffened cylindrical shell under initial hydrostatic pressure, based on Flügge classical thin shell theory and orthotropic method in this paper. The results obtained are compared with those available in other literature. It has been proved that, free vibration analysis using wave propagation approach with shear diaphragm–shear diaphragm (SD–SD) boundary conditions is absolutely equal to the traditional method. To evaluate the validity and accuracy of the wave propagation approach, an exact solution for arbitrary boundary conditions is also proposed in this paper. The comparisons between these two approaches are carried out for clamped–clamped (C–C) and clamped–shear diaphragm (C–SD) boundary conditions. The results show that wave propagation has high accuracy for long shell and large circumferential numbers. [Copyright &y& Elsevier]

Dynamic economic dispatch plays an important role in power system operation, which is a complicated non-linear constrained optimization problem. It has non-smooth and non-convex characteristics when generation unit valve-point effects are taken into account. Environmental awareness and recent environmental policies have forced electric utilities to restructure their practices to account for their emission impacts. The dynamic economic/environmental dispatch problem is studied in the present analysis; this article proposes a hybrid approach. In the first stage, a non-dominated sorting genetic algorithm-II is employed to approximate the set of Pareto solutions through an evolutionary optimization process. In the subsequent stage, a multi-attribute decision-making approach is adopted to rank these solutions from best to worst and to determinate the best solution in a deterministic environment with a single decision-maker. This hybrid approach is tested on a ten-unit system to illustrate the analysis process. Pareto frontiers are obtained, and the ranking of Pareto solutions is based on entropy weight and the technique for order preference by similarity to ideal solution. A single objective optimization example is also provided for comparison. Results obtained show that the hybrid approach has a great potential in handling the multi-objective optimization problem. [ABSTRACT FROM AUTHOR]

Numerous real-world problems relating to ship design are characterized by many alternatives as well as multiple conflicting objectives. Ship design is a complex endeavor requiring the successful coordination of many different disciplines, both technical and nontechnical. Conceptual design is the least defined stage of the ship design process and seeks to define the basic payloads and ship size characteristics. A hybrid approach for multiobjective optimization study of ship's principal parameters in conceptual design is proposed in the present analysis. In the first stage, a multiple objective genetic algorithm (MOGA) is employed to approximate the set of Pareto solution through an evolutionary optimization process. In the subsequent stage, a multiattribute decision making (MADM) approach is adopted to rank these solutions from best to worst and to determine the best solution in a deterministic environment with a single decision maker. A bulk carrier example, with 6 parameters, 3 criteria, and 14 constraints is conducted to illustrate the analysis process in present study. Pareto frontiers are obtained, and the ranking of the Pareto solution set is based on entropy weight and TOPSIS method. The ideal solution is compared with those from classic multiobjective methods. [ABSTRACT FROM AUTHOR]

Abstract: The vibration of ring-stiffened cylinders associated with arbitrary boundary conditions is investigated. Displacements of cylinders can be easily described by trigonometric functions when the cylinders are shear diaphragms supported at both ends. As to other boundary conditions, exponential functions are used and axial factors are introduced. An eighth-order algebraic equation for this axial factor is derived. The physical meaning of the axial factor is studied. Both analytical and numerical studies prove that, when the axial factor is a pure imaginary number, the cylinder appears to have a certain length with shear diaphragm boundary conditions. The effects of shell parameters and hydrostatic pressure on the axial factor are determined in the analysis. [Copyright &y& Elsevier]

Following Flügge's exact derivation for the buckling of cylindrical shells, the equations of motion for dynamic loading of a circular cylindrical shell under external hydrostatic pressure have been formulated. The normal mode theory is used to provide transient dynamic response for the equations of motion. The responses of displacements, strain, and stress are obtained for the area of impact, while those outside the area of impact are also calculated. The accuracy of normal mode theory and Timoshenko shell theory are examined in this paper. [ABSTRACT FROM AUTHOR]

Abstract: Paraformaldehyde fixation of platelets stabilizes surface antigens while altering some that are associated with cellular activation. Present experiments show that the asymmetric distribution of phosphatidylserine in platelets was especially sensitive to paraformaldehyde treatment. It was found that this reagent induced a dose- and time-dependent translocation of phosphatidylserine to the membrane surface as measured by annexin V binding and flow cytometry. The percent phosphatidylserine-positive cells increased from about 5% to >90%. Chelation of extracellular Ca2+ with EGTA partially blocked this translocation. Spectrofluorimetric analysis of fluo-3 loaded platelets indicates that paraformaldehyde caused a concomitant elevation of intracellular Ca2+ concentrations, [Ca2+]i. ATP levels also declined in paraformaldehyde-treated cells, suggesting that the rise in [Ca2+]i ensued in part from decreased activity of calcium pumps. Previous studies indicate that phosphatidylserine externalization arises from Ca2+-activated randomization of membrane phospholipids and decreased transport of phosphatidylserine from the outer to the inner leaflet of the plasma membrane. In light of present results, paraformaldehyde fixation is best avoided particularly in studies involving platelet apoptosis or activation. [Copyright &y& Elsevier]

Nitric oxide (NO) is a reversible inhibitor of platelet activation that generates S-nitrosylated compounds in plasma. Since platelets are activated during processing to platelet concentrates and storage, NO is anticipated to dampen the rate of lesion development. Platelet-rich plasma (PRP) was separated into aliquots that were unfiltered, filtered to remove leukocytes, or treated with NO or nitrite before filtration. Platelets were resuspended and stored up to four days at 22 °C. Samples removed were measured for S-nitrosylation of plasma, P-Selectin release, complement activation, and cGMP levels. Direct infusion of a NO solution (authentic NO) to PRP before filtration decreased adherence of platelets and improved yields. An infusion rate resulting in 1/1000 dilution of a saturated NO solution was optimal. C3a formation and soluble P-Selectin released from NO-treated-filtered platelets were about half that in unfiltered and filtered controls after four days (p<0.05 by Student–Newman–Keuls method after ANOVA for repeated measures). Plasma isolated from NO-treated PRP combined with untreated platelets protected the latter to a similar extent. Increases in S-nitrosylated compounds in PRPs were correlated with NO effects on platelet recovery and storage. Sodium nitrite failed to inhibit platelet activation and cyclic GMP levels were significantly increased in NO-treated cells. Results indicate that NO inhibited platelet activation associated with processing and storage and suggest that slow release of NO from S-nitrosylated plasma components afforded long-term protection. The infusion of authentic NO into PRPs is potentially an efficacious method for generating anti-platelet compounds to inhibit storage lesions. [Copyright &y& Elsevier]

Dopant profiles near the semiconductor–oxide interface are critical for microelectronic device performance. As the incorporation of Si1−xGex into transistors continues to increase, it is necessary to understand the behavior of dopants in Si1−xGex. In this paper, the diffusion and electrical activation of phosphorus within a strained, single-crystal Si0.7Ge0.3 layer on Si during oxidation are reported. Both layers were uniformly doped, in situ, with an average phosphorus concentration of 4 × 1019 atoms/cm3. After high-temperature oxidation, secondary ion mass spectrometry measurements revealed that the bulk of the phosphorus diffuses out of only the SiGe layer and segregates at the oxidizing SiGe–SiO2 interface. Hall effect measurements corroborate the observed phosphorus loss and show that the phosphorus diffusing to the oxidizing interface is electrically inactive. Through density functional theory (DFT) calculations, it is shown that phosphorus interstitials prefer sites near the SiGe–SiO2 interface. Finally, based on a combination of experimental data and DFT calculations, we propose that the phosphorus atoms are displaced from their lattice sites by Ge interstitials that are generated during SiGe oxidation. The phosphorus atoms then migrate toward the SiGe–SiO2 interface through a novel mechanism of hopping between Ge sites as P–Ge split interstitials. Once they reach the interface, they are electrically inactive, potentially in the form of interstitial clusters or as part of the reconstructed interface or oxide. [ABSTRACT FROM AUTHOR]

During the implementation process of identification systems, multiple factors need to be considered at the same time. Due to the large amount of calculation and the randomness of the signal, the automatic identification capability of the machine is currently poor, especially for continuous signal. In order to solve this problem, a neuron fuzzy identification system was described based on a complex nonlinear mathematical model, which was designed from both hardware and software aspects of the system. The hardware architecture diagram was constructed based on the S3C:2440 microprocessor. The main modules include the power module, acquisition module, storage module, and output module. The DSP/BIOS system was used to construct the software framework diagram of the neuron fuzzy identification system to describe the identification process of video data stream, image data stream and control signal data. The software algorithm was designed based on the neuron fuzzy theory to establish a fuzzy similarity matrix and the best identification result was found by the maximum and minimum methods. The experimental results show that the designed system has higher recognition ability. When the frame length reaches 40 frames, the recognition rate increases to a larger value, the recognition rate is 75%, and the information is more accurate. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) remains one of the most prevalent malignant tumors worldwide. At present, tumor-associated macrophages (TAMs) are essential in the progression, metastasis, and drug resistance of tumors. Therefore, TAMs can be a crucial target for tumor treatment. Aims: We intended to investigate the TAM characteristics in GC and develop a risk signature based on TAM to predict the prognosis of GC patients. Methods: The single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq data were acquired from a publicly available database. We utilized the Seurat pipeline to process the scRNA-seq data and determine TAM cell types using marker genes. Univariate Cox regression analysis was utilized to examine TAM-related prognostic genes, and then we employed Lasso-Cox regression analysis, and Multivariate Cox regression analysis established a novel risk profile to forecast the clinical value of the model with a new nomogram combining risk profiles and clinicopathological characteristics. Results: The current study employed scRNA-seq data to identify five TAM clusters in GC, among which four were significantly associated with GC prognosis. Accordingly, we further developed a TAM-related risk signature utilizing nine genes. After evaluation, our model accurately predicted the prognosis of gastric cancer. Generally, GC patients with low TAMS scores exhibited a more favorable prognosis, greater benefits from immunotherapy, and higher levels of immune cell infiltration. Conclusions: The prognosis of GC can be effectively predicted by TAM-based risk signatures, and the signature may provide a new perspective for comprehensively guiding clinical diagnosis, prediction, and immunotherapy for gastric cancer. [ABSTRACT FROM AUTHOR]

Biochar application can alleviate the adverse effects of saline-alkali stress on crops. However, the long-term effects of one-off biochar application on soil physicochemical properties, salt concentration, nutrient availability, soil enzyme activities, and rice yield under highly saline-alkali paddy soils remain unclear. Here, a 6-year paddy field study was conducted in a saline-alkali paddy field using two nitrogen application levels (0 and 225 kg ha−1) and four biochar application rates [0 (T0), 1.5% (T1.5), 3.0% (T3.0), and 4.5% (T4.5) biochar, w/w]. The results showed that compared with T0, the bulk density (BD) under T1.5, T3.0, and T4.5 treatments significantly decreased by 11.21%, 16.33%, and 25.57%, while total porosity (Tp) and saturated hydraulic conductivity (Ks) increased by 19.15–27.34% and 3217.78–5539.83%, respectively. Biochar consistently improved soil macro-aggregates, mean weight diameter (MWD), and the percentage of water-stable aggregates (PWSA) over the years. Additionally, one-off application of biochar continuously reduced the soil Na+ concentration, Na+/K+ ratio, Na+/Ca2+ ratio, saturated paste extract (ECe), exchangeable sodium percentage (ESP), and sodium adsorption ratio (SARe). However, it reduced the pH in 2021 and 2022 only. It enhanced the concentration of K+, Ca2+, Mg2+, and cation exchange capacity (CEC) over the 6-year study, indicating its longer-term positive impact. Furthermore, the one-off biochar application, especially under high application rate treatments (T3.0 and T4.5), significantly and continuously improved nutrient availability and soil enzyme activities. However, alkali-hydrolysable nitrogen (AN) decreased in the initial year of biochar application. The grain yield of T1.5, T3.0, and T4.5 surpassed that of T0 by 116.38%, 141.24%, and 145.20%, respectively. Notably, the rice yield reached its peak with the treatment of 3.0% (w/w) in all 6 years of study period. These findings offered new perspectives on repairing and improving soil quality and production ability of highly saline-alkali paddy soils. Highlights: A long-term (6-year), one-off application of biochar was conducted in a highly saline-alkali paddy field. Biochar consistently decreased soil BD, increased Tp, Ks, and improved soil aggregates. Biochar showed a sustained ability to alleviate saline-alkali stress. The continuous improvement of soil functions acted on the increase of rice yield. [ABSTRACT FROM AUTHOR]

Plutonium-239 + 240 and 137Cs in the environment can usually be used to track the impact of nuclear activities on the environment, and have become important tools in environmental geochemical studies. In this study, nine sediment cores (E1-E9) in Lake East Dongting were collected and measured for the activity concentration of 239+240Pu, 137Cs and the atomic ratio of 240Pu/239Pu, and then their vertical distribution characteristics were analyzed. The results show that: the activity concentrations of 137Cs and 239+240Pu in Lake East Dongting ranged from 5.26 ± 0.43 to 28.6 ± 2.23 Bq kg−1 and 0.29 ± 0.02 to 1.37 ± 0.09 Bq kg−1, with an average of 7.48 ± 0.68 Bq kg−1 and 0.39 ± 0.03 Bq kg−1, respectively. The atomic ratios of 240Pu/239Pu are 0.168 ± 0.012–0.211 ± 0.015, which are basically consistent with the global atmospheric deposition. The vertical profiles of 137Cs and 239+240Pu in sediment cores show obvious single-peak distribution in E1-E6 and bimodal distribution in E7-E9. The results of sedimentation rates calculated by 137Cs and 239+240Pu method ranged from 0.59 cm y−1 to 1.99 cm y−1 with a mean of 1.18 cm y−1 and 0.61 cm y−1 to 2.18 cm y−1 with a mean of 1.26 cm y−1. The inventories of 137Cs and 239+240Pu in nine sediment cores are 5.87–10.8 kBq m−2 and 307–545 Bq m−2, which are about 8–14 and 9–15 times the inventory in the global average atmospheric deposition at the same latitude respectively. Comparing the results of the sedimentation rates and the inventories from different sampling points indicates that extreme climatic events and human activities have a significant impact on sediment environment of Lake East Dongting. • A total of 540 samples from nine sediment cores were analyzed. • A comprehensive water system consisting of three different sampling areas was studied. • Sedimentation rates were calculated by using both 137Cs and 239+240Pu methods. • Ratios of the inventories suggest 137Cs and 239+240Pu mostly come from riverine input and human activities. [ABSTRACT FROM AUTHOR]

In this article, a new nonsmooth Kalman filtering (KF) method is proposed for noise suppression of the compound sandwich with backlash and dead zone. Based on the characteristics of the system, a nonsmooth stochastic state‐space equation is constructed. Then, nonsmooth KF is developed to adapt the nonsmooth stochastic state space model. The filter can switch automatically among different operating zones according to the operating conditions. Moreover, the convergence of the switchable compound nonsmooth KF is discussed. Subsequently, a motor‐driving mechanical transmission system which can be described as a compound nonsmooth nonlinear sandwich system with backlash and dead zone is studied as an application case. Finally, the comparison between the proposed filtering scheme and conventional filter are presented. It is demonstrated that the nonsmooth KF has a better performance than the conventional one in terms of convergence and accuracy in state estimation under noisy environment. [ABSTRACT FROM AUTHOR]

Atmospheric turbulence and wind speed distributions are essential in determining the quality of astronomical sites and implementing adaptive optics systems. In this study, the optical turbulence with a general turbulence model and the wind speed characteristics at Lenghu are investigated by employing the 21-yr European Centre for Medium-Range Weather Forecasts' fifth set of reanalysis (ERA5) data. The vertical distributions and seasonal behaviours of the wind speed and atmospheric turbulence are analysed. The wind speed values at 200 hPa pressure level (V 200) are low in spring and summer except for June, and high in autumn and winter. The highest and lowest values of V 200 at Lenghu are 39.93 m s−1 in September and 27.48 m s−1 in April, respectively. Additionally, atmospheric conditions are relatively stable above 20 km throughout the year. The locations of the peaks in the |$C_n^2$| profiles correspond to the tropopause and the jet wind stream regions at the Lenghu site. Furthermore, the median seeing value from ERA5 is 0.72 arcsec, generally consistent with the statistically measured value of 0.75 arcsec. Moreover, the astronomical parameters (r 0, θAO, and τAO) were initially provided at the Lenghu site. The median values of r 0, ε, θAO, and τAO are 15.17 cm, 0.72 arcsec, 1.19 arcsec, and 2.83 ms, respectively, thus providing the potential reference for astronomical applications. [ABSTRACT FROM AUTHOR]

Introduction: Gut microbiota dysbiosis is a key factor of the pathogenesis of post‐stroke depression (PSD). PSD is associated with increased hippocampal neuronal apoptosis and decreased synaptic connectivity. Inulin can be involved in hippocampal neuron protection through the microbiome–gut–brain axis. However, the neuroprotective effects of inulin in PSD are still to be further investigated. Methods: By utilizing the GEO public database, we identify differentially expressed genes in the hippocampus following inulin intake. This can help us discover key signaling pathways through functional enrichment analysis. Furthermore, we validate the expression levels of signaling molecules in a rat model of PSD and examine the effects of inulin on behavioral changes and body weight. Additionally, conducting a microbiome analysis to identify significantly different microbial populations and perform correlation analysis. Results: The intake of inulin significantly up‐regulated mitogen‐activated protein kinase signaling pathway in the hippocampus. Inulin changed in the gut microbiota structure, leading to an increase in the abundance of Lactobacillus and Clostridium_sensu_stricto_1 in the intestines of PSD rats, while decreasing the abundance of Ruminococcus UCG_005, Prevotella_9, Oscillospiraceae, and Clostridia UCG_014. Furthermore, the inulin diet elevated levels of insulin‐like growth factor 1 in the serum, which showed a positive correlation with the abundance of Lactobacillus. Notably, the consumption of inulin‐enriched diet increased activity levels and preference for sugar water in PSD rats, while also reducing body weight. Conclusion: These findings highlight the potential therapeutic benefits of inulin in the management of depression and emphasize the importance of maintaining a healthy gut microbiota for PSD. [ABSTRACT FROM AUTHOR]

A worldwide search is currently being conducted to determine the most appropriate sites for the next generation of large optical and infrared telescopes. Here, we report a global map of atmospheric optical turbulence-associated parameter (atmospheric coherence length) based on the fifth generation of European Centre for Medium Range Weather Forecasts re-analysis data set and results for atmospheric coherence lengths at European Southern Observatory and Tibetan Plateau locations (all at mid-latitudes). These confirm the accuracy of the global atmospheric optical turbulence model, but also the simulation result reveals that an excellent atmospheric calm site exist at the Ethiopian Plateau (at a latitude of ∼10°N) outside of the rainy season. The Ethiopian Plateau is the highest plateau in Africa, known as the 'Roof of Africa', with an average elevation of over 2500 m, and thus potentially provides good opportunities for astronomy and astrophysics. The median atmospheric coherence length at the Ethiopian Plateau was 17.7 cm and approximately 75 per cent of the time above 15.6 cm for dry conditions, indicating a very calm atmosphere. Although favourable atmospheric turbulence conditions at the Ethiopian Plateau were found from the global turbulence model, due to the complete lack of infrastructure it has never been visited, meaning that additional validation experiments are required. [ABSTRACT FROM AUTHOR]

The connections between the primary and secondary growth of trees allows better understanding of the dynamics of carbon sequestration in forest ecosystems. The relationship between primary and secondary growth of trees could change due to the diverging responses of meristems to climate warming. In this study, the bud phenology and radial growth dynamics of Qinghai spruce (Picea crassifolia) in arid and semi-arid areas of China in 2019 and 2020 were weekly monitored to analyze their response to different weather conditions and their links with carbon sink. Xylem anatomical traits (i.e. lumen radial diameter and cell wall thickness) were quantified along cell radial files after the end of xylem lignification to calculate the early-to-latewood transition date. Winter and early spring (January–March) were warmer in 2020 with a colder April compared with 2019. Precipitation in April–June was lower in 2020 than in 2019. In 2019, bud phenology occurred earlier, while the onset of xylem formation and the early-to-latewood transition date were delayed. The duration from the beginning of split bud and exposed shoot to the early-to-latewood transition date was positively correlated with the radial width of earlywood (accounting for ~80% of xylem width) and total xylem width. The longer duration of xylem cell division did not increase xylem cell production and radial width. Moreover, the duration from bud burst to the early-to-latewood transition date in 2020 was negatively linked with early phloem cell production as compared with 2019. Our findings suggest that warm conditions in winter and early spring promote the xylogenesis of Qinghai spruce, but might delay bud burst. However, the xylem width increments largely depend on the duration from bud burst to the start of latewood cell division rather than on the earlier xylogenesis and longer duration of xylem cell differentiation induced by warm conditions. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive site survey of the Delingha site on the northern Tibetan Plateau from 2012 to 2014. In this campaign, we investigated 24 h continuous astronomical seeing, meteorological properties, and |$C_{n}^{2}$| in the ground layer (GL). The results show that the median seeing is 3.46 arcsec during the day and 1.80 arcsec during the night. The best nighttime seeing occurs in summer (1.66 arcsec), while the worst occurs in autumn (1.96 arcsec). Seeing exhibits obvious diurnal behaviour, with the worst seeing occurring around mid-day (11:00 to 14:00, Beijing time), and the best seeing just before sunset (18:00 to 20:00, Beijing time). Moreover, the Delingha site has good meteorological properties for astronomical observations during the measurement period, especially the low median wind speed (2.8 m s−1) and great temperature inversion (day: −0.3 K, night: 0.6 K). As for the vertical distribution of |$C_{n}^{2}$|⁠ , the exponential h −0.46 dependence of |$C_{n}^{2}$| varying with height in the GL is also obtained, and its power index is significantly related to the seasons. Furthermore, we calculated the contribution of optical turbulence in the GL to the whole atmosphere. Turbulence within the GL contributes significantly in summer, and its contribution can reach more than 35 per cent. Finally, we present the complete dependence analysis of seeing on meteorological parameters at the Delingha site. The results show that the best seeing tends to occur when the temperature inversion is sufficiently large, but the dependence of seeing on wind speed is not significant. [ABSTRACT FROM AUTHOR]

Stroke is a cerebrovascular disease that results in decreased blood flow. Although Panax notoginseng (PN), a Chinese herbal medicine, has been proven to promote stroke recovery, its molecular mechanism remains unclear. In this study, middle cerebral artery occlusion (MCAO) was induced in rats with thrombi generated by thread and subsequently treated with PN. After that, staining with 2,3,5-triphenyltetrazolium chloride was employed to evaluate the infarcted area, and electron microscopy was used to assess ultrastructural changes of the neurovascular unit. RNA-Seq was performed to determine the differential expressed genes (DEGs) which were then verified by qPCR. In total, 817 DEGs were identified to be related to the therapeutic effect of PN on stroke recovery. Further analysis by Gene Oncology analysis and Kyoto Encyclopedia of Genes and Genomes revealed that most of these genes were involved in the biological function of nerves and blood vessels through the regulation of neuroactive live receptor interactions of PI3K-Akt, Rap1, cAMP, and cGMP-PKG signaling, which included in the 18 pathways identified in our research, of which, 9 were reported firstly that related to PN's neuroprotective effect. This research sheds light on the potential molecular mechanisms underlying the effects of PN on stroke recovery. [ABSTRACT FROM AUTHOR]

Cloud occurrences, vertical structures, and along-track horizontal scales over East Asia are studied using four years (2007–2010) of CloudSat 2B-CLDCLASS-LIDAR data. The CloudSat 2B-CLDCLASS-LIDAR data employs combined CloudSat radar and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) measurements to provide by far the most accurate detections of cloud boundaries and their vertical structures. The mean cloud occurrence frequency over East Asia is 66.3%, which is 13.8% and 21.6% higher than that from the Cloud–Aerosol LIdar with Orthogonal Polarization (CALIOP) level 2 5-km cloud layer product and the CloudSat 2B-GEOPROF product, respectively. Cloud-top heights over East Asia show three local peaks at approximately 1.5 km, 10 km, and 15 km above ground level (AGL), indicating different mid-altitude cloud formation mechanisms from those over the tropics. Significant fractions of low-level cloud, mid-level cloud, and high-level cloud have thicknesses smaller than 0.5 km, indicating that models with vertical resolutions lower than 0.5 km have difficulties resolving those clouds. The average cloud along-track horizontal scale over East Asia is 82.0 km. Probability distribution functions (PDFs) of cloud along-track horizontal scales suggest that approximately 81.2% of the clouds over East Asia cannot be resolved by climate models with a grid resolution of 1°. The results from this study can be used to improve cloud parameterizations in climate models and validate model simulations of clouds over East Asia. [ABSTRACT FROM AUTHOR]

This study evaluated the Pb(II) sorption capacity of jujube pit biochar (JPB) in aqueous solution, which was derived from jujube pit by pyrolysis and used as a promising and economical adsorbent. More importantly, the utilization of JPB could realize the recycling of agricultural residues. The JPB was characterized using conventional science technologies, including SEM, BET and FT-IR, and the sorption capacity of JPB for lead ions was investigated according to different adsorption parameters, such as the kinetics data, solution pH, isotherms data, coexisting ions of Na+ and K+, desorption and reusability, and solution temperature. The results of kinetics data suggested that the lead ion adsorption process by JPB could be fast to reach equilibrium within 30 min. Additionally, the adsorption capacity of JPB for Pb(II) was calculated to be maximum for 137.1 mg/g at pH 6.0. More importantly, after five cycles of desorption and reuse, the JPB still reached 70% of its original adsorption capacity. All the results suggested that JPB had a broad application prospect for the purification of lead ions in practical. [ABSTRACT FROM AUTHOR]

This study investigated the co-compost product of the shell and seed cake of Camellia oleifera Abel, which is a small evergreen tree in the family Theaceae. Tannin and saponin contents in compost samples at different time-points and their compositional changes, as well as their relationships with nutrients and compost maturity, were analyzed using an UPLC-triple-TOF/MS system. Our results showed that tannins in the compost samples mainly consisted of 11 phenolic acid compounds, of which four small-molecule phenolic acid compounds were found in low contents. Saponins mainly consisted of five saponin aglycones (A, B, C, D, E) and four of their derivatives in C. oleifera. Microbially secreted enzymes converted the large-molecule phenolic acid compounds into small-molecule compounds and their derivatives, while saponins were decomposed into saponin aglycones. Contents of tannin and saponin had correlations with the C/N ratio, germination index (GI), and the Solvita maturity index. After composting, the content of tannin was reduced to less than 1%, and the content of saponin was not more than 2%. And compost products were safe. [ABSTRACT FROM AUTHOR]

In this paper, the periodic state of a class of nonlinear hydrodynamic models is studied. This study is applicable to many fields, such as engineering, cybernetics and so on. We use the Runge Kutta algorithm. First, we give a four order nonlinear hydrodynamic model based on the Runge Kutta algorithm. Then, we study the periodic dynamic characteristics of the nonlinear model and establish some new sufficient conditions. The results of our study promote and improve the existing results. And the numerical results are also verified by the numerical experiments. Therefore, the study of this paper has a great help to master the periodic motion of the fluid. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the success rate, methods and associated complications of left ventricular lead (LVL) extraction and venous pathway reimplantation in patients with cardiac resynchronization therapy device/defibrillator (CRT/CRTD). A retrospective analysis was performed in the patients who underwent CRT/CRTD extraction and reimplantation at our hospital from January 2012 to October 2018. The methods, patient complications and success rate of extraction and reimplantation of LVL were analyzed. A total of 54 patients underwent CRT/CRTD removal (pacemaker infection, n=51; LVL dysfunction, n=3; CRT/CRTD, 34/20). A total of 54 LVLs were removed (3 active electrodes and 51 passive electrodes). The average implantation duration of the LVL was 53.5 months (range, 1–204 months), whereas the success rate of the LVL extraction was 100% (94% completely removed and 6% clinically removed. A total of 6 patients (11%) were treated only by manual traction, whereas the remaining patients had their LVL successfully removed using extraction tools. In the peri-operative period, one fatality occurred (2%). The highest complication rate of the lead extraction was 2% and no minor complications were observed. A total of 36 patients were reimplanted on the right side, which was successful in 31 cases (success rate, 86.1%), whereas 3 cases were successfully reimplanted on the left side. The total success rate of LVL reimplantation was 87.2%. The procedure of the LVL removal and reimplantation exhibited a high success rate and a lower incidence of complications compared with that in patients with cardiac devices. [ABSTRACT FROM AUTHOR]

Accurate knowledge of the optical turbulence (C n 2) in the atmospheric surface layer is of great significance for the applications of various ground-based optical systems (e.g., astronomical observation, laser communication and target detection), however, many methods using instruments to measure C n 2 are limited spatially and temporally and they are more difficult and expensive in severe environments, which makes estimations a less expensive and convenient alternative. This study introduces a method where the products of Weather Research and Forecasting (WRF) model coupled with Monin–Obukhov similarity (MOS) theory is used to estimate the value of C n 2 in the surface layer, and the performance of this method is evaluated against the corresponding C n 2 dataset from the in-situ micro-thermometer during a campaign over south-west China. The variance between the estimated C n 2 and measured C n 2 is found to be comparable to the observed variance of the temporal due to temporal and spatial variations of the atmospheric turbulence. Evaluation against direct observations shows that this approach can well estimate C n 2 time series with some error in some time periods, and both the estimated C n 2 and the measured C n 2 are more consistent in trend and magnitude in general. Given these validated results, this method has the potential to be a useful tool in a wide range of ground-based optical applications. [ABSTRACT FROM AUTHOR]

In this paper, we present comprehensive night-time seeing statistics at the Lenghu site using data collected between 2018 and 2021 using a differential image motion monitor. The results show that the median seeing is 0.80 arcsec, which slightly larger than that previously reported due to climate change. Additionally, we investigated the annual, seasonal, and monthly seeing statistics, as well as possible hourly seeing trends in each season. The results demonstrate that the seeing at the Lenghu site is very stable, with monthly median seeing varying from 0.6 to 0.95 arcsec. The seasonal dependence of seeing shows obvious variations over different years. The best year of seeing was 2019 (0.74 arcsec), and the best seeing occurred in spring (0.68 arcsec) to early summer (June, 0.63 arcsec), while the worst seeing occurred in winter (0.80 arcsec). The minimum seeing value throughout the night is at approximately three hours before dawn. Furthermore, wind speed profiles, especially V 200 (particularly the wind speed at 200 mbar), are important parameters for evaluating astronomical sites in terms of their suitability for adaptive optics. We first show the complete monthly average behaviours of the wind speed profile and V 200 using the European Center for Medium-Range Weather Forecast reanalysis data sets. The results demonstrate the annual periodicity and variability of V 200, and the yearly V 200 modulation function is also provided. V 200 maintains large values throughout the autumn (average: 35.01 m s−1) and winter (average: 34.33 m s−1), while the minimum V 200 occurs in spring (average: 27.93 m s−1). [ABSTRACT FROM AUTHOR]

Forest stock volume (FSV) is a major indicator of forest ecosystem health and it also plays an important part in understanding the worldwide carbon cycle. A precise comprehension of the distribution patterns and variations of FSV is crucial in the assessment of the sequestration potential of forest carbon and optimization of the management programs of the forest carbon sink. In this study, a novel vegetation index based on Sentinel-2 data for modeling FSV with the random forest (RF) algorithm in Helan Mountains, China has been developed. Among all the other variables and with a correlation coefficient of r = 0.778, the novel vegetation index (NDVIRE) developed based on the red-edge bands of the Sentinel-2 data was the most significant. Meanwhile, the model that combined bands and vegetation indices (bands + VIs-based model, BVBM) performed best in the training phase (R2 = 0.93, RMSE = 10.82 m3ha−1) and testing phase (R2 = 0.60, RMSE = 27.05 m3ha−1). Using the best training model, the FSV of the Helan Mountains was first mapped and an accuracy of 80.46% was obtained. The novel vegetation index developed based on the red-edge bands of the Sentinel-2 data and RF algorithm is thus the most effective method to assess the FSV. In addition, this method can provide a new method to estimate the FSV in other areas, especially in the management of forest carbon sequestration. [ABSTRACT FROM AUTHOR]

In this study, we devised a constraint method, called multi-model ensemble pattern (MEP), to estimate the refractive index structure parameter ( C n 2 ) profiles based on observational data and multiple existing models. We verified this approach against radiosonde data from field campaigns in China's eastern and northern coastal areas. Multi-dimensional statistical evaluations for the C n 2 profiles and integrated astronomical parameters have proved MEP's relatively reliable performance in estimating optical turbulence in the atmosphere. The correlation coefficients of MEP and measurement overall C n 2 in two areas are up to 0.65 and 0.76. A much higher correlation can be found for a single radiosonde profile. Meanwhile, the difference evaluation of integrated astronomical parameters also shows its relatively robust performance compared to a single model. The prowess of this reliable approach allows us to carry out regional investigation on optical turbulence features with routine meteorological data soon. [ABSTRACT FROM AUTHOR]

The rigid-flexible coupling impact contact dynamic model between coal gangue and hydraulic support was established and the contact response difference in the support induced by the difference in impacted components and coal/gangue properties was compared and studied. The research of coal chemistry shows that the structure of coal determines the physical and chemical properties of coal, while the structure of coal rock mass controls the failure mechanism of coal rock mass; that is, the structural control of the catastrophic failure of coal rock in a general sense, and its failure form and strength are related to the shape of the structural plane and the physical properties of the materials. Energy is the most basic driving force for world development and economic growth and the basis for human survival. In addition, the high value-added utilization of tectonic coal resources can be effectively improved by studying the macroscopic and microscopic characteristics, classification and mechanical properties of coal and coal-like materials. [Extracted from the article]

To improve the accuracy of atmospheric visibility (V) prediction based on machine learning in different pollution scenarios, a new atmospheric visibility prediction method based on the stacking fusion model (VSFM) is established in this paper. The new method uses the stacking strategy to fuse two base learners—eXtreme gradient boosting (XGBoost) and light gradient boosting machine (LightGBM)—to optimize prediction accuracy. Furthermore, seasonal feature importance evaluations and feature selection were utilized to optimize prediction accuracy in different seasons with different pollution sources. The new VSFM was applied to 1-year environmental and meteorological data measured in Qingdao, China. Compared to other traditional non-stacking models, the new VSFM improved precision during different seasons, especially in extremely low-visibility scenarios (V< 2 km). The TS score of the VSFM was significantly better than that of other models. For extremely low-visibility scenarios, the VSFM had a threat score (TS) of 0.5, while the best performance of other models was less than 0.27. The new method is promising for atmospheric visibility prediction under complex urban pollution conditions. The research results can also improve our understanding of the factors that influence urban visibility. [ABSTRACT FROM AUTHOR]

Aims: Saline-alkali soil seriously restricts the crop's photosynthesis rate and yield formation. Biochar addition could alleviate the adverse impacts of saline-alkali stress in crops. However, little information is available on the ionic accumulation and photosynthesis rate of rice in highly saline-alkali paddy fields. This study aimed to evaluated the influence of the peanut shell biochar on leaf ionic concentration, stress physiology indices, photosynthesis related parameters and rice yield in highly saline-alkali paddy field condition. Methods: Field experiment was carried out using two nitrogen application rate treatments (0 and 225 kg N ha−1) and four biochar applied rate treatments (0%, 1.5%, 3.0% and 4.5% w/w). The field experiment was arranged in a complete randomized design with three replications. Results: The results show that peanut shell biochar significantly reduced the leaf Na+ concentration, Na+/K+ ratio, abscisic acid and malondialdehyde concentration of rice, while enhanced leaf K+ concentration, and improved leaf water status and relative electrical leakage in treatments both with or without N fertilization. Furthermore, peanut shell biochar could provide beneficial effects on chlorophyll concentration, leaf N concentration, leaf area index, photosynthetic potential, stomatal conductance, and transpiration rates, which is of great benefit to the enhancement of leaf photosynthesis rate and net assimilation rate of rice population. In addition, the biomass, grain yield and harvested index were increased. Conclusions: These results indicated that peanut shell biochar could effectively ameliorate saline–alkali stress and increase rice yield by regulating of leaf ionic concentration and improving leaf photosynthesis rate. [ABSTRACT FROM AUTHOR]

The frequent outbreak of dust storms every spring is one of the extreme weathers in East Asia. Geostationary meteorological satellite thermal infrared (TIR) imagery provides observations for high‐frequency, all‐day, large‐scale monitoring of dust sources and transport. This study proposes an integrated method to detect dust over East Asia by using the multispectral and multi‐temporal Himawari‐8/Advanced Himawari Imager (AHI) TIR observations, based on a Feedforward Neural Network (FNN) model and the Robust Principal Component Analysis based Anomalous Dust Detection (ADD) method. The FNN model is trained to map the multispectral Brightness Temperatures (BTs) to the three category probabilities (i.e., cloud, dust, and clear sky), and the ADD method calculates the dust score by normalizing multi‐temporal BT difference anomalous variation. The Integrated Dust Index (IDI) reflects the quantified dust confidence of the AHI pixel, which is defined as the sum of the dust probability and the dust score. The IDI was evaluated using 2 months of the Sentinel‐5P TROPOMI Ultraviolet Aerosol Index and achieved a total dust detection accuracy above 90%. A comparison with Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation nighttime observations shows that the IDI can also detect dust at night. The times series IDI of the massive 14–16 March 2021 dust storm show its capabilities to trace dust sources and monitor dust transport. Key Points: The dust has distinct thermal infrared spectral features and can cause significant anomalous variations in satellite observationsThe feedforward neural network model and the robust principal component analysis are combined to calculate the Integrated Dust Index (IDI)Multi‐source validation data have proved the IDI to be an effective metric for dust detection and transmission monitoring [ABSTRACT FROM AUTHOR]

The refractive index structure constant C n 2 near the ocean surface is an important parameter for studying atmospheric optical turbulence over the ocean. The measured refractive index structure constant and meteorological parameters, such as temperature and three-dimensional wind speed, near the sea surface on the South China Sea during the period from January to November 2020 were analyzed. On the basis of Monin–Obukhov similarity theory, the dimensionless temperature structure parameter function f T near the sea surface was established, and a new parameterized model of the near-sea surface was proposed. The new model improved the error of the widely used model proposed by Wyngaard in 1973 (W73) and better reproduced the daily variation in the measured C n 2 . Further analysis of the seasonal applicability of the new model indicated that the correlation coefficients between the estimated and measured C n 2 in the spring, summer, autumn, and winter were 0.94, 0.94, 0.95, and 0.89, respectively, and the root mean square errors were 0.32, 0.41, 0.46, and 0.40 m−2/3, respectively. Compared with the C n 2 estimated by the W73 model, the correlation coefficient of C n 2 estimated by the new model and measured by the micro-thermometer increased by 0.05–0.27 and the root mean square error decreased by 0.04–0.56. The improved f T demonstrated higher accuracy than the existing models, which can lay a foundation for estimating turbulence parameters in different sea areas. [ABSTRACT FROM AUTHOR]

As the use of cardiac implantable electronic devices (CIED) has increased in recent years, the need for transvenous lead extraction (TLE) has also steadily increased. However, the TLE procedure could lead to serious complications and even death. Clinical decision-making tools are necessary for predicting these adverse events, but the appropriate tools have not yet been developed. To explore the possible predictors and develop a clinical model to predict TLE related adverse events. All the patients who were admitted to our cardiac center for TLE from January 2014 to January 2021 were included in this study. The patient information, device baseline characteristics, procedure-related information, complications and outcomes were recorded. Independent predictors of TLE related adverse events were identified by univariate, LASSO and multivariate analysis. A nomogram for predicting these adverse events was developed based on these independent predictors. Calibration and decision curve analysis were conducted to evaluate the nomogram. One thousand and one hundred patients were included in this study, 778 (70.7%) were male and the median age was 68 years old. A total of 2,208 leads were extracted and 2.01±0.74 leads were extracted per procedure. Fifty-five patients (5%) developed adverse events including minor complications (2.4%), major complications (2.3%) and death (0.27%). Seven independent predictors for TLE related adverse events were identified and selected to establish the nomogram including BMI, female gender, hypoalbuminemia, number of extracted leads>3, longest dwell time of the extracted leads and manual traction. The area under the receiver operating characteristic (ROC) curve (AUC) for the prediction model was 0.774. Calibration curve and decision curve analysis showed that the nomogram had good prediction performance. TLE related adverse events are some of the key issues that concern clinicians. We have identified seven independent factors and established a predictive model that may help clinicians identify at-risk patients and create better plans for lead extraction. • Transvenous lead extraction was the gold standard for CIED related complications. • Effective predictors may help clinicians identify at-risk patients. • Clinical model for predicting TLE related adverse events are still lacking. • Predictors were selected by univariate, LASSO and multivariate regression analysis. • A nomogram with good predictive ability was built to predict TLE complications. [ABSTRACT FROM AUTHOR]

During the mining activity under the super-thick nappe formed by thrust fault, the law of mine pressure behavior is complex, and it is difficult to control the deformation and failure of surrounding rock. Combined with the actual engineering conditions, the influence of different roof lithology conditions, the thickness of nappe, the mining height, the size of the barrier coal pillar, and the creep time on mine pressure behavior was studied by UDEC numerical simulation software. The results showed that with the advancement of the coal face, due to the influence of the mining of the coal face and the slip dislocation of the super-thick nappe along the thrust faults, the roof-to-floor convergence, the two-sided convergence, and the maximum concentrated stress in the roadway-concentrated areas are significantly increased. For the above five influencing factors, the greater the thickness of the nappe and the mining height, the longer the creep time, and the stronger the ground pressure behavior. The larger the size of the barrier coal pillar, the stronger the roof lithology, and the gentler the ground pressure behavior. The research results can provide some reference for monitoring the law of ground pressure behavior in roadway-concentrated areas under super-thick nappe. [ABSTRACT FROM AUTHOR]

A precise air pollution forecast is the basis for targeted pollution control and sustained improvements in air quality. It is desirable and crucial to select the most suitable model for air pollution forecasting (APF). To achieve this goal, this paper provides a comprehensive evaluation of performances of different models in simulating the most common air pollutants (e.g., PM2.5, NO2, SO2, and CO) in Guangzhou (23.13° N, 113.26° E), China. To simulate temporal variations of the above-mentioned air pollutant concentrations in Guangzhou in September and October 2020, we use a numerical forecasting model (i.e., the Weather Research and Forecasting model with Chemistry (WRF-Chem)) and two artificial intelligence models (i.e., the back propagation neural network (BPNN) model and the long short-term memory (LSTM) model). WRF-Chem is also used to simulate the meteorological elements (e.g., the 2 m temperature (T2), 2 m relative humidity (RH), and 10 m wind speed and direction (WS, WD)). In order to investigate the simulation accuracies of classical APF models, we simultaneously compare the simulations of the WRF-Chem, BPNN, and LSTM models to ground truth observations. Comparative assessment results show that WRF-Chem simulated air pollutant (i.e., PM2.5, NO2, SO2, and CO) concentrations have the best correlations with ground measurements (i.e., Pearson correlation coefficient R = 0.88, 0.73, 0.61, and 0.61, respectively). Furthermore, to evaluate model performance in terms of accuracy and stability, the normalized mean bias (NMB, %) and mean fractional bias (MFB, %) are adopted as the standard performance metrics (SPMs) proposed by Boylan et al. The comparison results indicate that when simulating PM2.5, WRF-Chem was more effective than the BPNN but less effective than the LSTM. While simulating concentrations of NO2, SO2, and CO, the WRF-Chem model performed better than the BPNN and LSTM models. With regards to WRF-Chem, the NMBs and MFBs for the PM2.5 simulations are, respectively, 6.49% and 0.02%, –11.96% and –0.031% for NO2, 7.93% and 0.019% for CO, and 5.04% and 0.012% for SO2. Our results suggest that WRF-Chem has superior performance and better accuracy than the NN-based prediction models, making it a promising and useful tool to accurately predict and forecast regional air pollutant concentrations on a city scale. [ABSTRACT FROM AUTHOR]

The high elevation, complex topography, and unique atmospheric circulations of the Tibetan Plateau (TP) make its optical turbulence characteristics different from those in low-elevation regions. In this study, the characteristics of the atmospheric refractive index structure constant ( C n 2 ) profiles in the Lhasa area at different strength states of the Asian summer monsoon anticyclone (ASMA) are analyzed based on precious in situ sounding data measured over the Lhasa in August 2018. C n 2 in the upper troposphere–lower stratosphere fluctuates significantly within a few days during the ASMA, particularly in the upper troposphere. The effect of the ASMA on C n 2 varies among the upper troposphere, tropopause, and lower stratosphere. The stronger and closer the ASMA is to Lhasa, the more pronounced is the "upper highs and lower lows" pressure field structure, which is beneficial for decreasing the potential temperature lapse rate. The decrease in static stability is an important condition for developing optical turbulence, elevating the tropopause height, and reducing the tropopause temperature. However, if strong high-pressure activity occurs at the lower pressure layer, such as at 500 hPa, an "upper highs and lower highs" pressure field structure forms over the Lhasa, increasing the potential temperature lapse rate and suppressing the convective intensity. Being almost unaffected by low-level atmospheric high-pressure activities, the ASMA, as the main influencing factor, mainly inhibits C n 2 in the tropopause and lower stratosphere. The variations of turbulence intensity in UTLS caused by ASMA activities also have a great influence on astronomical parameters, which will have certain guiding significance for astronomical site testing and observations. [ABSTRACT FROM AUTHOR]