BACKGROUND Although extensive research has investigated attentional biases based on the looming vulnerability model of anxiety,the characteristics of attentional biases in individuals with looming cognitive styles(LCS...BACKGROUND Although extensive research has investigated attentional biases based on the looming vulnerability model of anxiety,the characteristics of attentional biases in individuals with looming cognitive styles(LCS)remain incompletely elucidated.No prior eye-tracking studies have examined the spatiotemporal dynamics of their threat-related attentional preferences.AIM To investigate the nature and temporal pattern of attentional biases toward threat stimuli in individuals exhibiting different levels of LCS using eye-tracking technology.METHODS A total of 212 participants were stratified according to their Looming Maladaptive Style Questionnaire scores.From the high and low scoring subgroups,35 participants were randomly selected for an eye-tracking experiment using a classic dot-probe paradigm featuring threat and neutral images.Four eye-tracking metrics,including first fixation latency,first fixation duration,total fixation duration,and fixation count,were analyzed to assess detection speed,attentional orienting,initial maintenance/avoidance,and overall engagement.RESULTS Distinct attentional bias patterns were observed between high and low LCS groups.High LCS individuals exhibited a vigilance-avoidance pattern characterized by initial vigilance toward threat stimuli(evidenced by faster detection and preferential orienting),followed by attentional avoidance,alongside sustained attention maintenance to threat.CONCLUSION These findings reveal a temporal dissociation between early vigilance and later avoidance during threat processing in high LCS individuals,providing novel empirical evidence to refine models of cognitive vulnerability and attentional dynamics in threat perception.展开更多
Previous studies have shown that increases in pupil size are correlated with increasing cognitive processing demands. Our aim was to confirm whether these findings could be replicated with new portable and less obtrus...Previous studies have shown that increases in pupil size are correlated with increasing cognitive processing demands. Our aim was to confirm whether these findings could be replicated with new portable and less obtrusive eye-tracking technology. We assessed the percentage change of pupillary diameter from baseline as eight subjects completed a series of randomly ordered arithmetic problems of varying difficulty. The mean peak pupil diameter expressed as a percentage change from baseline was significantly greater when answering difficult questions compared to easier questions. Moreover, the time to reach peak pupillary diameter occurred significantly faster when participants answered easier questions compared to more difficult questions. Finally, there was a significant difference when all groups were compared to control. This experiment confirms findings of previous studies that show that pupillary size is related to cognitive processing demands. It also demonstrates that mobile eye-trackers can be used to reliably gather this type of data. Furthermore, this experiment provides the basis for future studies using eye-tracking technology in new environments, for example in the study of expertise and performance in medical crisis situations.展开更多
The endemic South African succulent plant Sceletium tortuosum (L.) N.E. Br., family Mesembryathemaceae, is known as kanna in Nama, kougoed in Afrikaans, and sceletium in English. The plant has been used as a tea and a...The endemic South African succulent plant Sceletium tortuosum (L.) N.E. Br., family Mesembryathemaceae, is known as kanna in Nama, kougoed in Afrikaans, and sceletium in English. The plant has been used as a tea and as a masticatory for millennia by indigenous San hunter-gatherers and Nama pastoralists for endurance and well-being. It has been reported that the plant “gives strength to their limbs, and takes away pain, and makes their memory strong”. The current investigation aimed at the psychophysiological characterization of 25.0 and 50.0 mg of a special extract marketed as Zembrin<sup>®</sup> in comparison to placebo using a new methodology called “EnkephaloVision”. This combination of EEG Neurocode-Tracking and Eye-Tracking allows for concomitant analysis of time epochs of only 364 ms duration. Spectral EEG analysis during cognitive and emotional challenges revealed statistically significant increases of delta (p < 0.01 during arithmetic calculation and watching a boring animal video) and theta spectral power (p < 0.10 during these same challenges) in the presence of Zembrin<sup>®</sup> within the frontal brain. It is these same increases of slow waves in the frontal brain that are described in the literature during performance of mental tests. This indicates a positive effect of Zembrin<sup>®</sup> on the electrical activity of the brain during cognitive processing. In addition, alpha1 and alpha2 spectral power in the frontal brain was increased during several challenges including brain teasing, arithmetic calculations and performance of a memory test. From the literature, increases of spectral alpha1 power indicate a greater degree of calmness and may represent decreased depressive symptoms, while increases in alpha2 waves have been related to memory. Beta2 waves increased during mental performance in the presence of the higher dosage of Zembrin<sup>®</sup> in parietal, occipital and temporal brain regions. In comparison to placebo, Zembrin<sup>®</sup> induced frequency changes in the brain, which have been related to enhanced attention and memory. These results may represent a positive action of Zembrin<sup>®</sup> on cognitive and emotional processes in the brain.展开更多
Measuring eye movement is a fundamental approach in cognitive science as it provides a variety of insightful parameters that reflect brain states such as visual attention and emotions.Combining eye-tracking with multi...Measuring eye movement is a fundamental approach in cognitive science as it provides a variety of insightful parameters that reflect brain states such as visual attention and emotions.Combining eye-tracking with multimodal neural recordings or manipulation techniques is beneficial for understanding the neural substrates of cognitive function.Many commercially-available and custom-built systems have been widely applied to awake,head-fixed small animals.However,the existing eyetracking systems used in freely-moving animals are still limited in terms of their compatibility with other devices and of the algorithm used to detect eye movements.Here,we report a novel system that integrates a general-purpose,easily compatible eye-tracking hardware with a robust eye feature-detection algorithm.With ultra-light hardware and a detachable design,the system allows for more implants to be added to the animal's exposed head and has a precise synchronization module to coordinate with other neural implants.Moreover,we systematically compared the performance of existing commonly-used pupil-detection approaches,and demonstrated that the proposed adaptive pupil feature-detection algorithm allows the analysis of more complex and dynamic eye-tracking data in freemoving animals.Synchronized eye-tracking and electroencephalogram recordings,as well as algorithm validation under five noise conditions,suggested that our system is flexibly adaptable and can be combined with a wide range of neural manipulation and recording technologies.展开更多
In this study,using Head Mounted Display(HMD),which is one of the biggest advantage of Virtual Reality(VR)environment,tracks the user’s gaze in 360◦video content,and examines how the gaze pattern is distributed accor...In this study,using Head Mounted Display(HMD),which is one of the biggest advantage of Virtual Reality(VR)environment,tracks the user’s gaze in 360◦video content,and examines how the gaze pattern is distributed according to the user’s immersion.As a result of analyzing the gaze pattern distribution of contents with high user immersion and contents with low user immersion through a questionnaire,it was confirmed that the higher the immersion,the more the gaze distribution tends to be concentrated in the center of the screen.Through this experiment,we were able to understand the factors that make users immerse themselves in the VR environment,and among them,the importance of the audio of the content was shown.Furthermore,it was found that the shape of the gaze distribution for grasping the degree of immersion by the subject of the content was different.While reviewing the experimental results,we also confirmed the necessity of research to recognize specific objects in a VR environment.展开更多
Assessment of websites remains a definite challenge within advertisement research. In order to gather objective information, one possibility exists in using Eye-Tracking. This method allows for determination of where ...Assessment of websites remains a definite challenge within advertisement research. In order to gather objective information, one possibility exists in using Eye-Tracking. This method allows for determination of where and how long particular areas of a website are fixed. However, longer fixation values do not necessarily reflect higher attention or even memorizing of the content. It could also mean that the content is too complicated. Therefore more information can be obtained by addition of quantitative analysis of brain electricity. Following the changes of the frequency content of electric brain activity has been recently introduced as “Neurocode-Tracking”. In the present study, quantitative assessment of websites has been performed by the combination of Neuro-code-Tracking with Eye-Tracking. Fast dynamic quantitative EEG recording with a time resolution of nearly 3 images/second provided electric power values according to frequency analysis in 17 brain regions (electrode positions). Particular values represented changes of electric brain activity, which were interpreted to represent visual perception, mental activation, concentration, stimulation, memory and tension according to earlier experience. Eye-Tracking was performed in a conventional manner by defining special areas of interest for detection of fixation lengths and time to first awareness. Ten male subjects (aged 36 ± 4.4 years) entered the study. They were asked to view Internet landing pages of five bank institutions: ComDirect, DKB, INGDiBa, Postbank and Targo-Bank. According to Eye-Track analysis, ComDirect was recognized to have the shortest time-to-awareness with respect to conditions, bonus, faces and application or address form. With respect to region of interest “service”, INGDiBa showed the shortest time-to-awareness. Neurocode-Tracking provided best results for INGDiBa with respect to mental activation and concentration. Stimulation and memory values were headed by Targo-Bank. Lowest tension was observed by the landing page of the Postbank. In summary, the combination of Neurocode-Tracking and Eye-Tracking provided much more information than any one of the methods used in separate. We therefore recommend this combination for the assessment and optimizing of Internet websites.展开更多
The term “neuromarketing” suggests a combination of marketing research and brain research. Within marketing research, objective assessment of TV commercials is performed by use of Eye-Tracking devices. Brain researc...The term “neuromarketing” suggests a combination of marketing research and brain research. Within marketing research, objective assessment of TV commercials is performed by use of Eye-Tracking devices. Brain research has been dominated by NMRI technologies during the last years. However, information content and time resolution are much better when monitoring electric activity by spectral analysis. The current experimental approach was initiated in order to test the combination of a newly developed EEG technology (Neurocode-Tracking) with commercially available Eye-Tracking. Ten male subjects were exposed to a reference recording condition (watching a fixed cross on the screen) followed by 5 TV commercials representing 5 different banks. Video films obtained from Eye-Tracking (so-called heat maps) were synchronized with the results of Neurocode-Tracking in form of a second video with a time resolution of 364 ms per image. Spectral power analysis of the EEG in different brain regions allowed for assessment of single scenes for cognitive and emotional responses. Averaging of data over the whole time course gave information on mental activation, attention, visual perception, memory, pleasure and tension. Comparison of the 5 commercials to reference recording revealed the clip of the Targo-Bank having the highest values with respect to mental activation and attention.These experiments have proven that the combination of Neurocode-Tracking with Eye-Tracking can be successfully used in advertisement research and gives valid information on individual as well as group dependent cognitive and emotional responses leading to objective assessment of TV commercials.展开更多
With the rapid growth of eye-tracking studies in translation process research, concomitant methodologicalproblems have become increasingly prominent. This paper starts with the discussion of the controversial “eye-mi...With the rapid growth of eye-tracking studies in translation process research, concomitant methodologicalproblems have become increasingly prominent. This paper starts with the discussion of the controversial “eye-mindassumption”, and then focuses on various threats to experimental validity in research design and problems witheye-tracking data filtering and analysis. It is hoped that this discussion would be beneficial to those who are now orwill be engaged in eye-tracking based translation studies.展开更多
This study focuses on seating arrangement and interpersonal distance as important aspects of nonverbal communication and aims to elucidate the optimal distance and angle between pharmacist and patient through an analy...This study focuses on seating arrangement and interpersonal distance as important aspects of nonverbal communication and aims to elucidate the optimal distance and angle between pharmacist and patient through an analysis based on the subjective evaluation of the patient and the objective evaluation of eye movements. Seven female simulated patients and one male and one female pharmacist cooperated as patients and pharmacists, respectively. The medication teaching scenes were set up with three pharmacist placements (face-to-face at 50 cm and 70 cm, 90-degree at 70 cm) and three hospital rooms (0-degree, 45-degree, 90-degree). Pupil diameter, blink rate, saccades, and fixation rate of the patient at each of these locations were measured using a Tobii Pro Glass 2. The patient’s subjective evaluation at each placement was also investigated using the conversation scale, which assesses the optimal distance for conversation. The results for the pharmacy setting revealed that pupils were significantly more mydriatic at the 50 cm point than at the other points. The results for the hospital room setting showed the greatest mydriasis at the 0-degree point. The result of the 50 cm point for the pharmacy setting and the 0-degree point for the hospital room setting was similar to that of the subjective evaluation. When the likelihood of saccades occurrence in the hospital room setting was compared, saccades were found to be most likely to occur when medication instructions were given to patients at the 0-degree point. We believe that using pupil diameter for interpersonal distance, and saccades for angle will enable more accurate determinations of the optimal distance and angle between pharmacist and patient. The results of the present study suggest that the 70 cm face-to-face point in the pharmacy and the 45-degree point in the ward may be suitable for medication instruction.展开更多
The pharmaco-dynamic action of plant-derived drugs still remains a big challenge in the field of pharmacology. This applies especially for the discovering of the possible mechanism of action. With respect to the brain...The pharmaco-dynamic action of plant-derived drugs still remains a big challenge in the field of pharmacology. This applies especially for the discovering of the possible mechanism of action. With respect to the brain, surrogate parameters may be very helpful. Non-invasive pharmaco-EEG has been proven to provide valid information on drug effects in general. Fast dynamic EEG recording with epoch length of 364 ms has now been achieved in combination with Eye-Tracking in order to elucidate single scenes during cognitive and emotional challenges (EnkephaloVision). The present investigation deals with the psychophysiological characterization of the effect of a plant-derived preparation marketed in Germany under the name of PASCOFLAIR® containing 425 mg of passionflower extract in subjects suffering from examination anxiety. Forty healthy volunteer subjects (17 men and 23 woman), with ages varying between 18 and 40 years (26 ± 6.726 for men and 25 ± 5.397 for women) were included into the study when having a score higher than 60 in the PAF (PrÜfungsangstfragebogen). Spectral power analysis of pre-drug data with respect to beta waves revealed a significant correlation to the score of the PAF. Increases of delta, theta and beta waves as induced by 4 cognitive and 4 emotional challenges were attenuated in the presence of 2 tablets of PASCOFLAIR® already 45 minutes after intake in a statistically significant manner in comparison to placebo. Regarding attenuation of beta1 and beta2 spectral power, effects on glutamatergic and GABAergic neurotransmission, respectively, can be suspected according to our knowledge of frequency—transmitter relations. Accordingly, this attenuation must be interpreted as ability to counteract examination induced stress symptoms. Results confirm and extend earlier experimental data showing a calming action of PASCOFLAIR®.展开更多
To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fract...To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on conductivity.Using reservoir production parameters and the discrete elementmethod,multispherical proppants were constructed.Additionally,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting fractures.Results indicate that turbulent kinetic energy is an intrinsic factor affecting proppant transport.Moreover,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture conductivity.Compared to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures.展开更多
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi...Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems.展开更多
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar...This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu.展开更多
Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this cha...Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this challenge,nonlinear stress boundaries for a numerical model are determined through regression analysis of a series of nonlinear coefficient matrices,which are derived from the bubbling method.Considering the randomness and flexibility of the bubbling method,a parametric study is conducted to determine recommended ranges for these parameters,including the standard deviation(σb)of bubble radii,the non-uniform coefficient matrix number(λ)for nonlinear stress boundaries,and the number(m)and positions of in situ stress measurement points.A model case study provides a reference for the selection of these parameters.Additionally,when the nonlinear in situ stress inversion method is employed,stress distortion inevitably occurs near model boundaries,aligning with the Saint Venant's principle.Two strategies are proposed accordingly:employing a systematic reduction of nonlinear coefficients to achieve high inversion accuracy while minimizing significant stress distortion,and excluding regions with severe stress distortion near the model edges while utilizing the central part of the model for subsequent simulations.These two strategies have been successfully implemented in the nonlinear in situ stress inversion of the Xincheng Gold Mine and have achieved higher inversion accuracy than the linear method.Specifically,the linear and nonlinear inversion methods yield root mean square errors(RMSE)of 4.15 and 3.2,and inversion relative errors(δAve)of 22.08%and 17.55%,respectively.Therefore,the nonlinear inversion method outperforms the traditional multiple linear regression method,even in the presence of a systematic reduction in the nonlinear stress boundaries.展开更多
The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytica...The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.展开更多
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi...Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications.展开更多
Bearing is an indispensable key component in mechanical equipment,and its working state is directly related to the stability and safety of the whole equipment.In recent years,with the rapid development of artificial i...Bearing is an indispensable key component in mechanical equipment,and its working state is directly related to the stability and safety of the whole equipment.In recent years,with the rapid development of artificial intelligence technology,especially the breakthrough of deep learning technology,it provides a new idea for bearing fault diagnosis.Deep learning can automatically learn features from a large amount of data,has a strong nonlinear modeling ability,and can effectively solve the problems existing in traditional methods.Aiming at the key problems in bearing fault diagnosis,this paper studies the fault diagnosis method based on deep learning,which not only provides a new solution for bearing fault diagnosis but also provides a reference for the application of deep learning in other mechanical fault diagnosis fields.展开更多
To quantify the seismic resilience of buildings,a method for evaluating functional loss from the component level to the overall building is proposed,and the dual-parameter seismic resilience assessment method based on...To quantify the seismic resilience of buildings,a method for evaluating functional loss from the component level to the overall building is proposed,and the dual-parameter seismic resilience assessment method based on postearthquake loss and recovery time is improved.A threelevel function tree model is established,which can consider the dynamic changes in weight coefficients of different category of components relative to their functional losses.Bayesian networks are utilized to quantify the impact of weather conditions,construction technology levels,and worker skill levels on component repair time.A method for determining the real-time functional recovery curve of buildings based on the component repair process is proposed.Taking a three-story teaching building as an example,the seismic resilience indices under basic earthquakes and rare earthquakes are calculated.The results show that the seismic resilience grade of the teaching building is comprehensively judged as GradeⅢ,and its resilience grade is more significantly affected by postearthquake loss.The proposed method can be used to predict the seismic resilience of buildings prior to earthquakes,identify weak components within buildings,and provide guidance for taking measures to enhance the seismic resilience of buildings.展开更多
Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.Howev...Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.However,the widened hydraulic excitation frequency may satisfy the blade resonance due to the time variation in the velocity and angle of attack of the ocean current,even resulting in blade fatigue and destructively interfering with grid stability.A key parameter that determines the resonance amplitude of the blade is the hydrodynamic damping ratio(HDR).However,HDR is difficult to obtain due to the complex fluid-structure interaction(FSI).Therefore,a literature review was conducted on the hydrodynamic damping characteristics of blade-like structures.The experimental and simulation methods used to identify and obtain the HDR quantitatively were described,placing emphasis on the experimental processes and simulation setups.Moreover,the accuracy and efficiency of different simulation methods were compared,and the modal work approach was recommended.The effects of key typical parameters,including flow velocity,angle of attack,gap,rotational speed,and cavitation,on the HDR were then summarized,and the suggestions on operating conditions were presented from the perspective of increasing the HDR.Subsequently,considering multiple flow parameters,several theoretical derivations and semi-empirical prediction formulas for HDR were introduced,and the accuracy and application were discussed.Based on the shortcomings of the existing research,the direction of future research was finally determined.The current work offers a clear understanding of the HDR of blade-like structures,which could improve the evaluation accuracy of flow-induced vibration in the design stage.展开更多
基金Supported by the Shanghai Municipal Health Commission,China,No.GWV-10.2-YQ46.
文摘BACKGROUND Although extensive research has investigated attentional biases based on the looming vulnerability model of anxiety,the characteristics of attentional biases in individuals with looming cognitive styles(LCS)remain incompletely elucidated.No prior eye-tracking studies have examined the spatiotemporal dynamics of their threat-related attentional preferences.AIM To investigate the nature and temporal pattern of attentional biases toward threat stimuli in individuals exhibiting different levels of LCS using eye-tracking technology.METHODS A total of 212 participants were stratified according to their Looming Maladaptive Style Questionnaire scores.From the high and low scoring subgroups,35 participants were randomly selected for an eye-tracking experiment using a classic dot-probe paradigm featuring threat and neutral images.Four eye-tracking metrics,including first fixation latency,first fixation duration,total fixation duration,and fixation count,were analyzed to assess detection speed,attentional orienting,initial maintenance/avoidance,and overall engagement.RESULTS Distinct attentional bias patterns were observed between high and low LCS groups.High LCS individuals exhibited a vigilance-avoidance pattern characterized by initial vigilance toward threat stimuli(evidenced by faster detection and preferential orienting),followed by attentional avoidance,alongside sustained attention maintenance to threat.CONCLUSION These findings reveal a temporal dissociation between early vigilance and later avoidance during threat processing in high LCS individuals,providing novel empirical evidence to refine models of cognitive vulnerability and attentional dynamics in threat perception.
文摘Previous studies have shown that increases in pupil size are correlated with increasing cognitive processing demands. Our aim was to confirm whether these findings could be replicated with new portable and less obtrusive eye-tracking technology. We assessed the percentage change of pupillary diameter from baseline as eight subjects completed a series of randomly ordered arithmetic problems of varying difficulty. The mean peak pupil diameter expressed as a percentage change from baseline was significantly greater when answering difficult questions compared to easier questions. Moreover, the time to reach peak pupillary diameter occurred significantly faster when participants answered easier questions compared to more difficult questions. Finally, there was a significant difference when all groups were compared to control. This experiment confirms findings of previous studies that show that pupillary size is related to cognitive processing demands. It also demonstrates that mobile eye-trackers can be used to reliably gather this type of data. Furthermore, this experiment provides the basis for future studies using eye-tracking technology in new environments, for example in the study of expertise and performance in medical crisis situations.
文摘The endemic South African succulent plant Sceletium tortuosum (L.) N.E. Br., family Mesembryathemaceae, is known as kanna in Nama, kougoed in Afrikaans, and sceletium in English. The plant has been used as a tea and as a masticatory for millennia by indigenous San hunter-gatherers and Nama pastoralists for endurance and well-being. It has been reported that the plant “gives strength to their limbs, and takes away pain, and makes their memory strong”. The current investigation aimed at the psychophysiological characterization of 25.0 and 50.0 mg of a special extract marketed as Zembrin<sup>®</sup> in comparison to placebo using a new methodology called “EnkephaloVision”. This combination of EEG Neurocode-Tracking and Eye-Tracking allows for concomitant analysis of time epochs of only 364 ms duration. Spectral EEG analysis during cognitive and emotional challenges revealed statistically significant increases of delta (p < 0.01 during arithmetic calculation and watching a boring animal video) and theta spectral power (p < 0.10 during these same challenges) in the presence of Zembrin<sup>®</sup> within the frontal brain. It is these same increases of slow waves in the frontal brain that are described in the literature during performance of mental tests. This indicates a positive effect of Zembrin<sup>®</sup> on the electrical activity of the brain during cognitive processing. In addition, alpha1 and alpha2 spectral power in the frontal brain was increased during several challenges including brain teasing, arithmetic calculations and performance of a memory test. From the literature, increases of spectral alpha1 power indicate a greater degree of calmness and may represent decreased depressive symptoms, while increases in alpha2 waves have been related to memory. Beta2 waves increased during mental performance in the presence of the higher dosage of Zembrin<sup>®</sup> in parietal, occipital and temporal brain regions. In comparison to placebo, Zembrin<sup>®</sup> induced frequency changes in the brain, which have been related to enhanced attention and memory. These results may represent a positive action of Zembrin<sup>®</sup> on cognitive and emotional processes in the brain.
基金supported in part by the National Key R&D Program of China(2021ZD0203902 and 2018YFA0701403)the Key Area R&D Program of Guangdong Province(2018B030338001 and 2018B030331001)+9 种基金the National Natural Science Foundation of China(31500861,31630031,91732304,and 31930047)the Chang Jiang Scholars Program and the Ten Thousand Talent Program,the International Big Science Program Cultivating Project of the Chinese Academy of Science(CAS)(172644KYS820170004)the Strategic Priority Research Program of the CAS(XDB32030100)the Youth Innovation Promo-tion Association of the CAS(2017413)Shenzhen Government Basic Research Grants(JCYJ20170411140807570,JCYJ20170413164535041)the Science,Technology and Innovation Commission of Shenzhen Municipality(JCYJ20160429185235132)a Helmholtz-CAS joint research grant(GJHZ1508)the Guangdong Provincial Key Laboratory of Brain Connectome and Behavior(2017B030301017)the Guangdong Special Support Program,the Key Laboratory of the CAS(2019DP173024)the Shenzhen Key Science and Technology Infrastructure Planning Project(ZDKJ20190204002)。
文摘Measuring eye movement is a fundamental approach in cognitive science as it provides a variety of insightful parameters that reflect brain states such as visual attention and emotions.Combining eye-tracking with multimodal neural recordings or manipulation techniques is beneficial for understanding the neural substrates of cognitive function.Many commercially-available and custom-built systems have been widely applied to awake,head-fixed small animals.However,the existing eyetracking systems used in freely-moving animals are still limited in terms of their compatibility with other devices and of the algorithm used to detect eye movements.Here,we report a novel system that integrates a general-purpose,easily compatible eye-tracking hardware with a robust eye feature-detection algorithm.With ultra-light hardware and a detachable design,the system allows for more implants to be added to the animal's exposed head and has a precise synchronization module to coordinate with other neural implants.Moreover,we systematically compared the performance of existing commonly-used pupil-detection approaches,and demonstrated that the proposed adaptive pupil feature-detection algorithm allows the analysis of more complex and dynamic eye-tracking data in freemoving animals.Synchronized eye-tracking and electroencephalogram recordings,as well as algorithm validation under five noise conditions,suggested that our system is flexibly adaptable and can be combined with a wide range of neural manipulation and recording technologies.
基金This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF2021R1A2C2011966).
文摘In this study,using Head Mounted Display(HMD),which is one of the biggest advantage of Virtual Reality(VR)environment,tracks the user’s gaze in 360◦video content,and examines how the gaze pattern is distributed according to the user’s immersion.As a result of analyzing the gaze pattern distribution of contents with high user immersion and contents with low user immersion through a questionnaire,it was confirmed that the higher the immersion,the more the gaze distribution tends to be concentrated in the center of the screen.Through this experiment,we were able to understand the factors that make users immerse themselves in the VR environment,and among them,the importance of the audio of the content was shown.Furthermore,it was found that the shape of the gaze distribution for grasping the degree of immersion by the subject of the content was different.While reviewing the experimental results,we also confirmed the necessity of research to recognize specific objects in a VR environment.
文摘Assessment of websites remains a definite challenge within advertisement research. In order to gather objective information, one possibility exists in using Eye-Tracking. This method allows for determination of where and how long particular areas of a website are fixed. However, longer fixation values do not necessarily reflect higher attention or even memorizing of the content. It could also mean that the content is too complicated. Therefore more information can be obtained by addition of quantitative analysis of brain electricity. Following the changes of the frequency content of electric brain activity has been recently introduced as “Neurocode-Tracking”. In the present study, quantitative assessment of websites has been performed by the combination of Neuro-code-Tracking with Eye-Tracking. Fast dynamic quantitative EEG recording with a time resolution of nearly 3 images/second provided electric power values according to frequency analysis in 17 brain regions (electrode positions). Particular values represented changes of electric brain activity, which were interpreted to represent visual perception, mental activation, concentration, stimulation, memory and tension according to earlier experience. Eye-Tracking was performed in a conventional manner by defining special areas of interest for detection of fixation lengths and time to first awareness. Ten male subjects (aged 36 ± 4.4 years) entered the study. They were asked to view Internet landing pages of five bank institutions: ComDirect, DKB, INGDiBa, Postbank and Targo-Bank. According to Eye-Track analysis, ComDirect was recognized to have the shortest time-to-awareness with respect to conditions, bonus, faces and application or address form. With respect to region of interest “service”, INGDiBa showed the shortest time-to-awareness. Neurocode-Tracking provided best results for INGDiBa with respect to mental activation and concentration. Stimulation and memory values were headed by Targo-Bank. Lowest tension was observed by the landing page of the Postbank. In summary, the combination of Neurocode-Tracking and Eye-Tracking provided much more information than any one of the methods used in separate. We therefore recommend this combination for the assessment and optimizing of Internet websites.
文摘The term “neuromarketing” suggests a combination of marketing research and brain research. Within marketing research, objective assessment of TV commercials is performed by use of Eye-Tracking devices. Brain research has been dominated by NMRI technologies during the last years. However, information content and time resolution are much better when monitoring electric activity by spectral analysis. The current experimental approach was initiated in order to test the combination of a newly developed EEG technology (Neurocode-Tracking) with commercially available Eye-Tracking. Ten male subjects were exposed to a reference recording condition (watching a fixed cross on the screen) followed by 5 TV commercials representing 5 different banks. Video films obtained from Eye-Tracking (so-called heat maps) were synchronized with the results of Neurocode-Tracking in form of a second video with a time resolution of 364 ms per image. Spectral power analysis of the EEG in different brain regions allowed for assessment of single scenes for cognitive and emotional responses. Averaging of data over the whole time course gave information on mental activation, attention, visual perception, memory, pleasure and tension. Comparison of the 5 commercials to reference recording revealed the clip of the Targo-Bank having the highest values with respect to mental activation and attention.These experiments have proven that the combination of Neurocode-Tracking with Eye-Tracking can be successfully used in advertisement research and gives valid information on individual as well as group dependent cognitive and emotional responses leading to objective assessment of TV commercials.
文摘With the rapid growth of eye-tracking studies in translation process research, concomitant methodologicalproblems have become increasingly prominent. This paper starts with the discussion of the controversial “eye-mindassumption”, and then focuses on various threats to experimental validity in research design and problems witheye-tracking data filtering and analysis. It is hoped that this discussion would be beneficial to those who are now orwill be engaged in eye-tracking based translation studies.
文摘This study focuses on seating arrangement and interpersonal distance as important aspects of nonverbal communication and aims to elucidate the optimal distance and angle between pharmacist and patient through an analysis based on the subjective evaluation of the patient and the objective evaluation of eye movements. Seven female simulated patients and one male and one female pharmacist cooperated as patients and pharmacists, respectively. The medication teaching scenes were set up with three pharmacist placements (face-to-face at 50 cm and 70 cm, 90-degree at 70 cm) and three hospital rooms (0-degree, 45-degree, 90-degree). Pupil diameter, blink rate, saccades, and fixation rate of the patient at each of these locations were measured using a Tobii Pro Glass 2. The patient’s subjective evaluation at each placement was also investigated using the conversation scale, which assesses the optimal distance for conversation. The results for the pharmacy setting revealed that pupils were significantly more mydriatic at the 50 cm point than at the other points. The results for the hospital room setting showed the greatest mydriasis at the 0-degree point. The result of the 50 cm point for the pharmacy setting and the 0-degree point for the hospital room setting was similar to that of the subjective evaluation. When the likelihood of saccades occurrence in the hospital room setting was compared, saccades were found to be most likely to occur when medication instructions were given to patients at the 0-degree point. We believe that using pupil diameter for interpersonal distance, and saccades for angle will enable more accurate determinations of the optimal distance and angle between pharmacist and patient. The results of the present study suggest that the 70 cm face-to-face point in the pharmacy and the 45-degree point in the ward may be suitable for medication instruction.
文摘The pharmaco-dynamic action of plant-derived drugs still remains a big challenge in the field of pharmacology. This applies especially for the discovering of the possible mechanism of action. With respect to the brain, surrogate parameters may be very helpful. Non-invasive pharmaco-EEG has been proven to provide valid information on drug effects in general. Fast dynamic EEG recording with epoch length of 364 ms has now been achieved in combination with Eye-Tracking in order to elucidate single scenes during cognitive and emotional challenges (EnkephaloVision). The present investigation deals with the psychophysiological characterization of the effect of a plant-derived preparation marketed in Germany under the name of PASCOFLAIR® containing 425 mg of passionflower extract in subjects suffering from examination anxiety. Forty healthy volunteer subjects (17 men and 23 woman), with ages varying between 18 and 40 years (26 ± 6.726 for men and 25 ± 5.397 for women) were included into the study when having a score higher than 60 in the PAF (PrÜfungsangstfragebogen). Spectral power analysis of pre-drug data with respect to beta waves revealed a significant correlation to the score of the PAF. Increases of delta, theta and beta waves as induced by 4 cognitive and 4 emotional challenges were attenuated in the presence of 2 tablets of PASCOFLAIR® already 45 minutes after intake in a statistically significant manner in comparison to placebo. Regarding attenuation of beta1 and beta2 spectral power, effects on glutamatergic and GABAergic neurotransmission, respectively, can be suspected according to our knowledge of frequency—transmitter relations. Accordingly, this attenuation must be interpreted as ability to counteract examination induced stress symptoms. Results confirm and extend earlier experimental data showing a calming action of PASCOFLAIR®.
基金funded by the project of the Major Scientific and Technological Projects of CNOOC in the 14th Five-Year Plan(No.KJGG2022-0701)the CNOOC Research Institute(No.2020PFS-03).
文摘To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on conductivity.Using reservoir production parameters and the discrete elementmethod,multispherical proppants were constructed.Additionally,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting fractures.Results indicate that turbulent kinetic energy is an intrinsic factor affecting proppant transport.Moreover,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture conductivity.Compared to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures.
基金supported by the Innovation Foundation of Provincial Education Department of Gansu(2024B-005)the Gansu Province National Science Foundation(22YF7GA182)the Fundamental Research Funds for the Central Universities(No.lzujbky2022-kb01)。
文摘Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems.
文摘This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu.
基金funded by the National Key R&D Program of China(Grant No.2022YFC2903904)the National Natural Science Foundation of China(Grant Nos.51904057 and U1906208).
文摘Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this challenge,nonlinear stress boundaries for a numerical model are determined through regression analysis of a series of nonlinear coefficient matrices,which are derived from the bubbling method.Considering the randomness and flexibility of the bubbling method,a parametric study is conducted to determine recommended ranges for these parameters,including the standard deviation(σb)of bubble radii,the non-uniform coefficient matrix number(λ)for nonlinear stress boundaries,and the number(m)and positions of in situ stress measurement points.A model case study provides a reference for the selection of these parameters.Additionally,when the nonlinear in situ stress inversion method is employed,stress distortion inevitably occurs near model boundaries,aligning with the Saint Venant's principle.Two strategies are proposed accordingly:employing a systematic reduction of nonlinear coefficients to achieve high inversion accuracy while minimizing significant stress distortion,and excluding regions with severe stress distortion near the model edges while utilizing the central part of the model for subsequent simulations.These two strategies have been successfully implemented in the nonlinear in situ stress inversion of the Xincheng Gold Mine and have achieved higher inversion accuracy than the linear method.Specifically,the linear and nonlinear inversion methods yield root mean square errors(RMSE)of 4.15 and 3.2,and inversion relative errors(δAve)of 22.08%and 17.55%,respectively.Therefore,the nonlinear inversion method outperforms the traditional multiple linear regression method,even in the presence of a systematic reduction in the nonlinear stress boundaries.
基金supported by the National Natural Science Foundation of China(12172023).
文摘The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.
基金funded by the National Natural Science Foundation of China(No.41962016)the Natural Science Foundation of NingXia(Nos.2023AAC02023,2023A1218,and 2021AAC02006).
文摘Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications.
文摘Bearing is an indispensable key component in mechanical equipment,and its working state is directly related to the stability and safety of the whole equipment.In recent years,with the rapid development of artificial intelligence technology,especially the breakthrough of deep learning technology,it provides a new idea for bearing fault diagnosis.Deep learning can automatically learn features from a large amount of data,has a strong nonlinear modeling ability,and can effectively solve the problems existing in traditional methods.Aiming at the key problems in bearing fault diagnosis,this paper studies the fault diagnosis method based on deep learning,which not only provides a new solution for bearing fault diagnosis but also provides a reference for the application of deep learning in other mechanical fault diagnosis fields.
基金The National Key Research and Development Program of China(No.2023YFC3805003)。
文摘To quantify the seismic resilience of buildings,a method for evaluating functional loss from the component level to the overall building is proposed,and the dual-parameter seismic resilience assessment method based on postearthquake loss and recovery time is improved.A threelevel function tree model is established,which can consider the dynamic changes in weight coefficients of different category of components relative to their functional losses.Bayesian networks are utilized to quantify the impact of weather conditions,construction technology levels,and worker skill levels on component repair time.A method for determining the real-time functional recovery curve of buildings based on the component repair process is proposed.Taking a three-story teaching building as an example,the seismic resilience indices under basic earthquakes and rare earthquakes are calculated.The results show that the seismic resilience grade of the teaching building is comprehensively judged as GradeⅢ,and its resilience grade is more significantly affected by postearthquake loss.The proposed method can be used to predict the seismic resilience of buildings prior to earthquakes,identify weak components within buildings,and provide guidance for taking measures to enhance the seismic resilience of buildings.
基金Supported by the National Natural Science Foundation of China(Nos.52222904 and 52309117)China Postdoctoral Science Foundation(Nos.2022TQ0168 and 2023M731895).
文摘Ocean energy has progressively gained considerable interest due to its sufficient potential to meet the world’s energy demand,and the blade is the core component in electricity generation from the ocean current.However,the widened hydraulic excitation frequency may satisfy the blade resonance due to the time variation in the velocity and angle of attack of the ocean current,even resulting in blade fatigue and destructively interfering with grid stability.A key parameter that determines the resonance amplitude of the blade is the hydrodynamic damping ratio(HDR).However,HDR is difficult to obtain due to the complex fluid-structure interaction(FSI).Therefore,a literature review was conducted on the hydrodynamic damping characteristics of blade-like structures.The experimental and simulation methods used to identify and obtain the HDR quantitatively were described,placing emphasis on the experimental processes and simulation setups.Moreover,the accuracy and efficiency of different simulation methods were compared,and the modal work approach was recommended.The effects of key typical parameters,including flow velocity,angle of attack,gap,rotational speed,and cavitation,on the HDR were then summarized,and the suggestions on operating conditions were presented from the perspective of increasing the HDR.Subsequently,considering multiple flow parameters,several theoretical derivations and semi-empirical prediction formulas for HDR were introduced,and the accuracy and application were discussed.Based on the shortcomings of the existing research,the direction of future research was finally determined.The current work offers a clear understanding of the HDR of blade-like structures,which could improve the evaluation accuracy of flow-induced vibration in the design stage.
