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Instructors' speech and gestures are tightly integrated. However, little is known about the neural mechanisms by which different types of gestures affect learning. We conducted two experiments on the effects of gestures in video lectures that included an instructor and slides, with English vocabulary as the topic. In Experiment 1, we manipulated the instructor's gestures (beat gestures vs. pointing gestures vs. depictive gestures) on neural oscillations and learning performance. The electroencephalogram results showed that students had higher alpha power and higher beta power when the instructor used pointing gestures, suggesting lower sensorimotor involvement in processing. Pointing gestures produced lower learning performance than beat gestures and depictive gestures. In Experiment 2, we manipulated the instructor's pointing gestures and the richness of visual materials in video lectures. The results showed that the effectiveness of pointing gestures was moderated by the richness of the visual materials on the slide. Specifically, pointing gestures were more effective for complex versus simple learning materials. The findings suggest that electroencephalogram oscillations and learning performance vary with the type of gesture the instructor uses and the richness of visual materials in video lectures. This study has applied value for designing effective video lectures in many disciplines: (1) When a video lecture includes simple visual materials, a beat gesture and depictive gesture would be better; (2) when a video lecture includes complex visual materials, the instructor can produce pointing gestures to single out the learning content they are talking about.

Massive open online courses are one of the most prominent trends in higher education in recent years. Instructional videos play a significant role in the massive open online courses platform. This study tested the impact of sending danmaku related to video content versus sending danmaku not related to video content versus not sending danmaku in instructional video. We assessed students' achievement, learning satisfaction, social presence, and cognitive load. Adopting a quasi-experimental design, we collected data from 137 participants. Result revealed that the danmaku related to video content improved social presence, learning satisfaction, and learning achievement but created more cognitive load.

There are many sample preparation methods for heavy metal detection of soil samples, but each has its advantages and disadvantages. Based on the above two pretreatment methods, the detection limit, precision, accuracy and actual soil sample measurement value of mercury detection in soil by atomic fluorescence were compared with atomic fluorescence, and the results showed that the automatic digestion and pretreatment system (DEENA) could digest soil samples to meet the requirements of GB/T 22105.1-2008 standard. Moreover, there was no significant difference between the two digestion methods on the detection results of mercury in soil, and the automatic digestion and preparation system (DEENA) was convenient, operable and highly automated, which was more advantageous for sample digestion.

Aiming at the problem of large access to renewable energy and insufficient regulation capacity of microgrid systems, this paper introduces electro-hydrogen coupling to improve the flexible regulation capacity of microgrid systems. A mathematical model for power regulation of microgrid including renewable energy equipment and electro-hydrogen coupling equipment is analyzed and established. Based on this, a flexibility margin model for the system is established. Taking the total profit and flexibility margin over the entire life cycle as optimization objectives, a daily optimal scheduling model for microgrid is established. In order to reflect the optimization and adjustment ability of electro-hydrogen coupling, this paper develops a variety of scenarios for comparison, and uses an improved particle optimization algorithm to solve the scheduling plans for different scenarios. The analysis of a numerical example shows that the regulation and optimization ability of the electro-hydrogen coupling is much higher than that of traditional energy storage.

Micro-milling technology is an efficient method for machining titanium alloy thin-walled micro parts. However, the machinability of thin-walled microstructures can be greatly affected by chatters due to their weak stiffness, especially in difficult-to-machine materials like titanium alloys. In order to obtain high-quality thin-walled micro parts, a chatter mitigation strategy is presented and its mechanism is analyzed in this paper. The titanium alloy workpiece is submerged into a kind of high-viscosity fluid, which can improve machining stability by increasing the damping of the micro-milling process. The stability lobe diagrams (SLD) are established, and the machinability is analyzed and compared under different machining conditions. The cutting force, surface roughness, micro-tool wear, and dimension accuracy of thin-walled micro parts are selected as the evaluation criteria for the machinability assessment. Well-designed micro-milling experiments are carried out under dry, lubrication, and chatter mitigation conditions using the same cutting process parameters. The results show that the use of cutting fluid can effectively improve machinability under stable cutting processes, but the effect of cutting fluid is weakened under chatter machining. The proposed chatter mitigation strategy can suppress regenerative chatter throughout the micro-milling process for thin-walled micro parts and improve their machinability comprehensively. [ABSTRACT FROM AUTHOR]

Vision-based Continuous Sign Language Recognition (CSLR) is a challenging and weakly supervised task aimed at segmenting sign language from weakly annotated image stream sequences for recognition. Compared with Isolated Sign Language Recognition (ISLR), the biggest challenge of this work is that the image stream sequences have ambiguous time boundaries. Recent CSLR works have shown that the visual-level sign language recognition task focuses on image stream feature extraction and feature alignment, and overfitting is the most critical problem in the CSLR training process. After investigating the advanced CSLR models in recent years, we have identified that the key to this study is the adequate training of the feature extractor. Therefore, this paper proposes a CSLR model with Multi-state Feature Optimization (MFO), which is based on Fully Convolutional Network (FCN) and Connectionist Temporal Classification (CTC). The MFO mechanism supervises the multiple states of each Sign Gloss in the modeling process and provides more refined labels for training the CTC decoder, which can effectively solve the overfitting problem caused by training, while also significantly reducing the training cost in time. We validate the MFO method on the popular CSLR dataset and demonstrate that the model has better performance. [ABSTRACT FROM AUTHOR]

This study examined the development and trends in non-destructive testing technology for fruit quality. The status of the research field and the application hotspots were investigated to provide a reference for future research in this field. Relevant studies on the non-destructive testing of fruit quality published between 1993 and 2022 were identified in the core database Web of Science. The temporal distribution, spatial distribution, literature features, research progress, and leading research hotspots were quantified and visualised using bibliometrics. The findings revealed that there continues to be active research and publications on non-destructive testing technology for fruit quality, with a good development trend. China and the USA are the major contributors to research on non-destructive testing technology for fruit quality. The major research institutions include Zhejiang University and the United States Department of Agriculture. The major papers are published in Postharvest Biology and Technology and Acta Horticulturae, among others. These studies mainly focus on agriculture, food, and gardening, among other topics. The detection indices mainly concern internal quality, such as sugar degree and soluble solids, and apparent quality, such as hardness. The detection technologies mainly include electronic nose (E-nose) technology, machine vision technology, and spectral detection technology. In the future, technological developments in artificial intelligence and deep learning will further promote the maturation and application of non-destructive testing technologies for fruit quality. [ABSTRACT FROM AUTHOR]

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Micro-milling has found extensive applications in machining components with thin-walled microstructures, such as terahertz slow-wave structures, microfluidic chips, and micro-molds. Due to the influence of size effects, micro-milling exhibits higher specific energy consumption compared with traditional milling, implying that more energy is consumed to remove a unit volume of material, particularly in challenging-to-machine materials like Ti-6Al-4V. Historically, research on parameter optimization for micro-milling has predominantly focused on enhancing machining quality and efficiency, with limited attention given to energy efficiency. However, in the context of the "double carbon" strategy, energy conservation and emissions reduction have garnered significant attention in the manufacturing industry. Therefore, this paper proposes a micro-milling parameter-based power consumption model. Based on this, a specific energy consumption model can be obtained. Moreover, evolutionary algorithms are utilized for the optimization of micro-milling parameters, which aims to achieve comprehensive enhancements in both machinability and sustainability. The optimization objectives encompass improving surface quality, dimensional accuracy, material removal rate, and specific energy consumption during the micro-milling process for thin-walled micro-structures. Among them, NSGA-III achieves the best optimization results. Under conditions in which cutting energy consumption and processing efficiency are very close, the optimization outcomes based on NSGA-III lead to the best machining quality, including the minimum surface roughness and dimensional errors, and the largest surface fractal dimension. The optimal combination of micro-milling parameters is n = 28,800 rpm, fz = 2.6 μm/t, and ap = 62 μm. [ABSTRACT FROM AUTHOR]

Ferrous sulfate was crystallized from the waste electrolyte produced in electrolytic refining of Fe-PGMs alloy by solution crystallization method using anhydrous ethanol as the dissolution solvent. The effects of dissolution time, volume ratio of ethanol to water solution, dissolution temperature, stirring speed, aging time, and anhydrous ethanol dripping method on the crystallization rate of ferrous sulfate were investigated. The results showed that the maximum crystallization rate of ferrous sulfate reached 92.98% when the dissolution time was 60 min, the volume ratio of anhydrous ethanol to aqueous solution was 1:1, the dissolution temperature was 10 °C, the stirring speed was 200 r/min, the aging time was 60 min, and the ethanol was added dropwise. This process not only avoids environmental pollution caused by waste electrolyte during the electrolysis process, reduces the production of finished products, but also achieves the recycling and utilization of electrolyte in electrolytic Fe-PGMs alloys and Fe-PGMs alloy acid leaching solution, which is of great significance. [ABSTRACT FROM AUTHOR]

In this paper, three new species of the tribe Anthocoptini from China are described and illustrated. They are Aculops grewiaesp. nov. infesting Grewia biloba G.Don. (Malvaceae), Aculops koelreuteriaesp. nov. infesting Koelreuteria paniculata Laxm. (Sapindaceae) and Tegolophus pogonatherisp. nov. infesting Pogonatherum crinitum (Thunb.) Kunth (Poaceae). All of them are vagrants on lower leaf surface and cause no apparent symptom to their host plants. [ABSTRACT FROM AUTHOR]

In recent years, geographically weighted regression (GWR) models have been widely used to address the spatial heterogeneity and spatial autocorrelation of PM2.5, but these studies have not fully considered the effects of all potential variables on PM2.5 variation and have rarely optimized the models for residuals. Therefore, we first propose a modified GWR model based on principal component analysis (PCA-GWR), then introduce five different spatial interpolation methods of radial basis functions to correct the residuals of the PCA-GWR model, and finally construct five combinations of residual correction models to estimate regional PM2.5 concentrations. The results show that (1) the PCA-GWR model can fully consider the contributions of all potential explanatory variables to estimate PM2.5 concentrations and minimize the multicollinearity among explanatory variables, and the PM2.5 estimation accuracy and the fitting effect of the PCA-GWR model are better than the original GWR model. (2) All five residual correction combination models can better achieve the residual correction optimization of the PCA-GWR model, among which the PCA-GWR model corrected by Multiquadric Spline (MS) residual interpolation (PCA-GWRMS) has the most obvious accuracy improvement and more stable generalizability at different time scales. Therefore, the residual correction of PCA-GWR models using spatial interpolation methods is effective and feasible, and the results can provide references for regional PM2.5 spatial estimation and spatiotemporal mapping. (3) The PM2.5 concentrations in the study area are high in winter months (January, February, December) and low in summer months (June, July, August), and spatially, PM2.5 concentrations show a distribution of high north and low south. [ABSTRACT FROM AUTHOR]

Herein, the corrosion behaviors of Fe35Mn10Cr20Ni35 high‐entropy alloy (HEA) and commercial 304 stainless steel (304 SS) in 0.5 M H2SO4 aqueous solutions are evaluated. Potentiodynamic polarization test results indicate that both the prepared HEA and 304 SS possess a large passive interval, illustrating that they have a strong capability to form passive films. The prepared HEA possesses higher corrosion potentials and lower corrosion current densities than that of 304 SS, thus it has more superior corrosion resistance. The electrochemical impedance spectroscopy and electrical equivalent circuits results indicate that the charge‐transfer resistance of HEA is higher than that of 304 SS and the passive films of the prepared HEA is thicker than that of 304 SS. These indicate that the passive film on the prepared HEA has an excellent protective ability to prevent further corrosion. X‐Ray photoelectron spectroscopy results indicate that the passive film of the prepared HEA samples is mainly composed of compacted metal oxides, especially Cr2O3‐dense oxides, while the passive film of 304 SS is mainly composed of loose hydroxides and compacted metal oxides. That is the key reason why the prepared HEA has better corrosion resistance than 304 SS. [ABSTRACT FROM AUTHOR]

In this study, a novel β -1,3-glucan recognition protein gene (β-GRP) was identified from Melanotus cribricollis , and its potential role in the immune response was investigated. The full length of β-GRP cDNA (Accession Number: MT941530) was 1644 bp, encoding a protein composed of 428 amino acids. The theoretical molecular weight and the isoelectric point were 51.53 kDa and 6.17, respectively. The amino acid sequence of β -GRP from M. cribricollis was closely related to that of. β- GRP-like from Photinus pyralis , and was predicted to contain conserved GH16 domain without glucanase active site. The results of real-time quantitative PCR showed that fungal infection of Metarhizium pingshaense may significantly upregulated the expression level of β-GRP gene. The RNAi suppression of β-GRP gene expression significantly increased the corrected cumulative mortality. Meanwhile, antimicrobial peptide genes defensin and lysozyme were significantly downregulated after interference of β-GRP. Taken together, these results suggest that β-GRP of M. cribricollis probably participates in the host immune system by mediating the expression of antimicrobial peptides. This study provides comprehensive insights into the innate immune system of insect larvae. [ABSTRACT FROM AUTHOR]

In this paper, three new species of eriophyoid mites from Guangxi, China, are described and illustrated. They are as follows: Paraphytoptus niveaesp. nov. infesting Boehmeria nivea (L.) Gaudich. (Urticaceae), Boczekiana broussonetiaesp. nov. infesting Broussonetia papyrifera (L.) L'Hér. ex Vent. (Moraceae), and Trimeroptes kaempferisp. nov. infesting Broussonetia kaempferi Siebold (Moraceae). All three new species are vagrants on the lower leaf surface and cause no apparent symptom to their host plants. [ABSTRACT FROM AUTHOR]

Instructors' speech and gestures are tightly integrated. However, little is known about the neural mechanisms by which different types of gestures affect learning. We conducted two experiments on the effects of gestures in video lectures that included an instructor and slides, with English vocabulary as the topic. In Experiment 1, we manipulated the instructor's gestures (beat gestures vs. pointing gestures vs. depictive gestures) on neural oscillations and learning performance. The electroencephalogram results showed that students had higher alpha power and higher beta power when the instructor used pointing gestures, suggesting lower sensorimotor involvement in processing. Pointing gestures produced lower learning performance than beat gestures and depictive gestures. In Experiment 2, we manipulated the instructor's pointing gestures and the richness of visual materials in video lectures. The results showed that the effectiveness of pointing gestures was moderated by the richness of the visual materials on the slide. Specifically, pointing gestures were more effective for complex versus simple learning materials. The findings suggest that electroencephalogram oscillations and learning performance vary with the type of gesture the instructor uses and the richness of visual materials in video lectures. This study has applied value for designing effective video lectures in many disciplines: (1) When a video lecture includes simple visual materials, a beat gesture and depictive gesture would be better; (2) when a video lecture includes complex visual materials, the instructor can produce pointing gestures to single out the learning content they are talking about. Practitioner notesWhat is already known about this topic Instructors commonly produce gestures while they teach, and their gestures and speech are tightly integrated.Instructors often use three types of gestures: beat gestures, pointing gestures and depictive gestures.Different types of gestures influence learning via different neural mechanisms.What this paper adds Students' alpha power and beta power had lower amplitudes when observing an instructor's beat gestures, compared to pointing and depictive gestures.Students showed higher learning performance after viewing the video lectures with the instructor's beat and depictive gestures.An instructor's pointing gestures facilitated learning performance primarily in video lectures with complex visual materials (CVM) rather than simple visual material (SVM).Implications for practice and/or policy When a video lecture includes SVM, the instructor is encouraged to produce beat gestures and depictive gestures rather than pointing gestures.When a video lecture includes CVM, the instructor is encouraged to produce pointing gestures to single out the learning content they are talking about. [ABSTRACT FROM AUTHOR]

Dislocation behavior has been considered as the crucial reason for micro-scale plasticity and micro-damage of the diamond. In this research, based on the theory of discrete dislocation dynamics (DDD), the nanoscratch model was established to investigate the dislocation evolution and stress distributions of the chemical vapored deposition (CVD) diamond film, and further supported by experimental study. Well-designed nanoscratch experiments were performed to validate the simulation results. It can be found that dislocation multiplication occurred along the scratch path. Besides, the dislocation pile-up and local stress concentration are easier to be found inside the smaller grain stress concentration. And it causes the occurrence of crack initiation near the grain boundary. [ABSTRACT FROM AUTHOR]

Exosome and microRNAs (miRs) are implicated in ischemia/reperfusion (I/R) process. In this study, I/R mouse model was established, and exosomes derived from human umbilical cord mesenchymal stem cells (hUCMSCs) were isolated, identified, and injected to I/R mice to observe nerve injury and microglia M1 polarization. The differentially expressed genes in I/R microglia from databases were analyzed, and miRs differentially expressed in exosomes-treated microglia were analyzed by microarray. miR-26b-5p expression in hUCMSCs was intervened. Besides, microglia was extracted and co-cultured with SH-SY5Y or PC12 cells in oxygen-glucose deprivation/reperfusion (OGD/R) models to simulate I/R in vivo. Additionally, Toll-like receptor (TLR) activator GS-9620 was added to microglia. Exosomes alleviated nerve injury and inhibited M1 polarization in microglia. After I/R modeling, CH25H expression in microglia was upregulated but decreased after exosome treatment. miR-26b-5p was upregulated in microglia after exosome treatment and could target CH25H. Reduction in exosomal miR-26b-5p reversed the effects of hUCMSCs-exos on microglia. TLR pathway was activated in microglia after I/R but exosomes prevented its activation. Exosomal miR-26b-5p could repress M1 polarization of microglia by targeting CH25H to inactivate the TLR pathway, so as to relieve nerve injury after cerebral I/R. This investigation may offer new approaches for I/R treatment. [ABSTRACT FROM AUTHOR]

Massive open online courses are one of the most prominent trends in higher education in recent years. Instructional videos play a significant role in the massive open online courses platform. This study tested the impact of sending danmaku related to video content versus sending danmaku not related to video content versus not sending danmaku in instructional video. We assessed students' achievement, learning satisfaction, social presence, and cognitive load. Adopting a quasi-experimental design, we collected data from 137 participants. Result revealed that the danmaku related to video content improved social presence, learning satisfaction, and learning achievement but created more cognitive load. [ABSTRACT FROM AUTHOR]

Abstract Wireworms are recognized as economically important oligophagous pests of Phyllostachys bamboo shoot, which have caused a huge economic loss in South China. Studies of bamboo shoot wireworm control and management were seriously hampered by the lack of reliable identification of larvae. DNA barcoding has been proved to be an important and useful tool in species identification of morphologically cryptic insects. Accurate knowledge of damage-causing species and the phylogenic structure of elaterids will provide insight into their sustainable and effective management. Here, we use interspecific variation in COI and EF1-a as a robust method of identification and consider the intra- and interspecific genetic variation of bamboo wireworms. This approach has revealed that three Melanotus larvae occurred in Phyllostachys forest. The dominance of one species in different sampling location suggests there maybe underlying difference in habit and host plant preference. These data provide a starting point for determining the distribution of wireworm species feeding on bamboo shoots in South China. The inclusions would further aid identification of wireworm species and relationships between certain wireworm species with specific environments. Graphical abstract Unlabelled Image Highlights • Both mitochondrial and nuclear markers help in wireworm identification. • Three species of bamboo shoot wireworms were identified in South China. • Melanotus cribric ollis (Faldermann) proved to be dominant in bamboo forests. • Significant genetic differentiation was found in each bamboo shoot wireworm species. [ABSTRACT FROM AUTHOR]