Inhibitory effects of jujuboside A on EEG and hippocampal glutamate in hyperactive rat

In this study, the inhibitory effect ofjujuboside A (JuA) on a penicillin sodium (Na-PCN) induced hyperactivity model was investigated. Cortical EEG (electroencephalogram) and the concentration of hippocampal Glutamate (Glu) were monitored simultaneously in vivo as indicators of rat's excitatory state. Power spectral density (PSD) and gravity frequency of PSD were calculated. JuA (0.05 g/L and 0.1 g/L) inhibited the EEG excitation effect caused by Na-PCN by increasing the power of δ1 and δ2bands (P＜0.01 vs model) and lowering the gravity frequency of PSD (P＜0.01 vs model). JuA also remarkably reduced the Glu elevation induced by Na-PCN (P＜0.05 vs model). Diazepam also depressed Glu concentration and lowered the gravity frequency,but it showed a different EEG pattern in increased β2-activity (P＜0.01 vs model). EEG excitation caused by Na-PCN correlated with Glu elevation during the first hour. Neurophysiological inhibitory effects of JuA and diazepam were more persistent than their Glu inhibitoty effects.     

New findings for concreteness and imagery effects in written composition

This experiment investigated the effects ofword concreteness and either imagery, verbal,or control strategy instructions on thecomposition of written definitions. Resultsrevealed significant effects of wordconcreteness on several quantity and qualityvariables, but no significant effect ofstrategy instructions or interaction betweenconcreteness and strategy instructions. Results of self-ratings of strategies actuallyused in composing revealed that a mentalimagery strategy was used with concrete wordsand a verbal strategy was used with abstractwords regardless of strategy instructions. Findings replicated the results of Tirre,Manelis and Leicht [(1979) Journal of ReadingBehavior 11, 99–106] in the production ofwritten composition on word relationships, andpartially replicated the results of Sadoski,Kealy, Goetz and Paivio [(1997) Journal of EducationalPsychology 89, 518–526] in the timedwritten production of word definitions. Results are interpreted from Dual Coding Theoryand levels of processing perspectives.     

Synthesized Multi-Method to Detect and Classify Epileptic Waves in EEG

In order to sufficiently exploit the advantages of different signal processing methods, such as wavelet transformation (WT), artificial neural networks (ANN) and expert rules (ER), a synthesized multi-method was introduced to detect and classify the epileptic waves in the EEG data. Using this method, at first, the epileptic waves were detected from pre-processed EEG data at different scales by WT, then the characteristic parameters of the chosen candidates of epileptic waves were extracted and sent into the well-trained ANN to identify and classify the true epileptic waves,and at last, the detected epileptic waves were certificated by ER. The statistic results of detection and classification show that, the synthesized multi-method has a good capacity to extract signal features and to shield the signals from the random noise. This method is especially fit for the analysis of the biomedical signals in biomedical engineering which are usually non-placid and nonlinear.     

Individualization of data-segment-related parameters for improvement of EEG signal classification in brain-computer interface

In electroencephalogram (EEG) modeling techniques, data segment selection is the first and still an important step. The influence of a set of data-segment-related parameters on feature extraction and classification in an EEG-based brain-computer interface (BCI) was studied. An auto search algorithm was developed to study four datasegment-related parameters in each trial of 12 subjects’ EEG. The length of data segment (LDS), the start position of data (SPD) segment, AR order, and number of trials (NT) were used to build the model. The study showed that, compared with the classification ratio (CR) without parameter selection, the CR was increased by 20% to 30% with proper selection of these data-segment-related parameters, and the optimum parameter values were subject-dependent. This suggests that the data-segment-related parameters should be individualized when building models for BCI.     

Numerical magnitude processing in abacus-trained children with superior mathematical ability: an EEG study

Distance effect has been regarded as the best established marker of basic numerical magnitude processes and is related to individual mathematical abilities. A larger behavioral distance effect is suggested to be concomitant with lower mathematical achievement in children. However, the relationship between distance effect and superior mathematical abilities is unclear. One could get superior mathematical abilities by acquiring the skill of abacus-based mental calculation (AMC), which can be used to solve calculation problems with exceptional speed and high accuracy. In the current study, we explore the relationship between distance effect and superior mathematical abilities by examining whether and how the AMC training modifies numerical magnitude processing. Thus, mathematical competencies were tested in 18 abacus-trained children (who accepted the AMC training) and 18 non-trained children. Electroencephalography (EEG) waveforms were recorded when these children executed numerical comparison tasks in both Arabic digit and dot array forms. We found that: (a) the abacus-trained group had superior mathematical abilities than their peers; (b) distance effects were found both in behavioral results and on EEG waveforms; (c) the distance effect size of the average amplitude on the late negative-going component was different between groups in the digit task, with a larger effect size for abacus-trained children; (d) both the behavioral and EEG distance effects were modulated by the notation. These results revealed that the neural substrates of magnitude processing were modified by AMC training, and suggested that the mechanism of the representation of numerical magnitude for children with superior mathematical abilities was different from their peers. In addition, the results provide evidence for a view of non-abstract numerical representation.     

Millennial generation preservice teachers inspiring the design of teacher education

The article presents an interpretive phenomenological approach (IPA) to preservice teachers’ experiences of their current secondary teacher education programme (STEP) in Finland. The focus of the study is the millennial generation cohort in which new teachers comprise a key group to be studied because they will contribute to the future of education. Thirteen preservice teachers participated in the study. Their experiences are interpreted through the lenses of generation theory and contemporary teacher education research. The findings include three phenomenological themes that are core elements of STEP: time balance, reciprocal participation and meaningfulness. These themes are discussed and suggestions made for ways to transform teacher education to make it more relevant.     

Differences of math anxiety groups based on two measurements,MASS and EEG

This article investigated how mathematic anxiety (MA) of Korean middle school students could be reduced by comparing analytically their cognitive neuroscience and questionnaire results. We developed a three-hour Complex Treatment Program (CTP) on quadratic functions for the study. In the summer of 2016, we collected data of the pre and post MA questionnaires by Mathematics Anxiety Scale for Students (MASS), the percent of correct answers (PCA) and reaction time (RT) by E-prime program, and also brain-imaging data of the event related potentials (ERP) by Electroencephalograph (EEG) using computer-based functional F-G model. The result indicated the CTP to be effective with the group with higher math anxiety and the group with higher achievement respectively. The MASS result was verified with the better performance of PCA on type G, which was measured by E-prime program. Some interesting patterns were revealed on brain-imaging data by EEG, indicating more brain activities with the MA groups.     

非熟练汉-英双语者动词产出过程的重复启动效应研究

本研究旨在考察非熟练汉-英双语者动词产出过程的重复启动效应。研究采用重复启动范式,以60个汉、英对等翻译名词为实验材料。31名非英语专业本科生产出由呈现的名词刺激联想到的相关动词。研究结果表明：1)被试已学名词刺激引发的动词产出平均反应时显著短于其未学名词刺激,表明动词产出过程中存在重复启动效应;2)被试一语汉语动词产出的反应时和重复启动效应均显著小于其二语英语动词产出,这表明语言熟练程度影响非熟练汉-英双语者动词产出过程的重复启动效应。研究结果支持迁移适当加工观和修正等级模型。     

Abnormal cortical functional connections in Alzheimer＇s disease： analysis of inter- and intra-hemispheric EEG coherence

To investigate inter- and intra-hemispheric electroencephalography (EEG) coherence at rest and during photic stimulation of patients with Alzheimer‘s disease (AD). Thirty-five patients (12 males, 23 females; 52-64 y) and 33 sex- and age-matched controls (12 males, 21 females; 56-65 y) were recruited in the present study. EEG signals from C3-C4, P3-P4, TS-T6 and O1-O2 electrode pairs resulted from the inter-hemispheric action, and EEG signals from C3-P3, C4-P4, P3-O1, P4-O2, C3-O1, C4-O2, TS-O1 and T6-O2 electrode pairs resulted from the intra-hemispheric action. The influence of inter- and intra-hemispheric coherence on EEG activity with eyes closed was examined, using fast Fourier transformation from the 16 sampled channels. The frequencies of photic stimulation were fixed at 5, l0 and 15 Hz, respectively. The general decrease of AD patients in inter- and intra-hemispheric EEG coherence was more significant than that of the normal controls at the resting EEG, with most striking decrease observed in the alpha-1 (8.0-9.0 Hz) and alpha-2 (9.5-12.5 Hz) bands. During photic stimulation, inter- and intra-hemispheric EEG coherences of the AD patients having lower values in the alpha (9.5-10.5 Hz) band than those of the control group. It suggests that under stimulated and non-stimulated conditions, AD patients had impaired inter- and intra-hemispheric functional connections, indicating failure of brain activation in alpha-related frequency.     

Study on EEG power and coherence in patients with mild cognitive impairment during working memory task

To investigate the features of electroencephalography (EEG) power and coherence at rest and during a working memory task of patients with mild cognitive impairment (MCI). Thirty-five patients (17 males, 18 females; 52～71 years old) and 34 sex- and age-matched controls (17 males, 17 females; 51～63 years old) were recruited in the present study. Mini-Mental State Examination (MMSE) of 35 patients with MCI and 34 normal controls revealed that the scores of MCI patients did not differ significantly from those of normal controls (P＞0.05). Then, EEGs at rest and during working memory task with three levels of working memory load were recorded. The EEG power was computed over 10 channels: right and left frontal (F3, F4), central (C3,C4), parietal (P3, P4), temporal (TS, T6) and occipital (O1, O2); inter-hemispheric coherences were computed from five electrode pairs of F3-F4, C3-C4, P3-P4, T5-T6 and O1-O2 for delta (1.0～3.5 Hz), theta (4.0～7.5 Hz), alpha-1 (8.0～10.0 Hz), alpha-2 (10.5～13.0 Hz), beta-1 (13.5～18.0 Hz) and beta-2 (18.5～30.0 Hz) frequency bands. All values of the EEG power of MCI patients were found to be higher than those of normal controls at rest and during working memory tasks. Furthermore, the values of EEG power in the theta, alpha-1, alpha-2 and beta-1 bands of patients with MCI were significantly high (P＜0.05) in comparison with those of normal controls. Correlation analysis indicated a significant negative correlation between the EEG powers and MMSE scores. In addition, during working memory tasks, the EEG coherences in all bands were significantly higher in the MCI group in comparison with those in the control group (P＜0.05). However, there was no significant difference in EEG coherences between two groups at rest. These findings comprise evidence that MCI patients have higher EEG power at rest, and higher EEG power and coherence during working conditions. It suggests that MCI may be associated with compensatory processes at rest and during working memory tasks. Moreover, failure of normal cortical connections may be exist in MCI patients.     

Evaluating the effect of midpalatal corticotomy-assisted rapid maxillary expansion on the upper airway in young adults using computational fluid dynamics

Midpalatal corticotomy-assisted rapid maxillary expansion(MCRME)is a minimally invasive treatment of maxillary transverse deficiency(MTD)in young adults.However,the effect of MCRME on respiratory function still needs to be determined.In this study,we evaluated the changes in maxillary morphology and the upper airway following MCRME using computational fluid dynamics(CFD).Twenty patients with MTD(8 males,12 females;mean age 20.55 years)had cone-beam computed tomography(CBCT)images taken before and after MCRME.The CBCT data were used to construct a threedimensional(3 D)upper airway model.The upper airway flow characteristics were simulated using CFD,and measurements were made based on the CBCT images and CFD.The results showed that the widths of the palatal bone and nasal cavity,and the intermolar width were increased significantly after MCRME.The volume of the nasal cavity and nasopharynx increased significantly,while there were no obvious changes in the volumes of the oropharynx and hypopharynx.CFD simulation of the upper airway showed that the pressure drop and maximum velocity of the upper airway decreased significantly after treatment.Our results suggest that in these young adults with MTD,increasing the maxillary width,upper airway volume,and quantity of airflow by MCRME substantially improved upper airway ventilation.     

Inter-and intra-hemispheric EEG coherence in patients with mild cognitive impairment at rest and during working memory task

Objective： To assess functional relationship by calculating inter- and intra-hemispheric electroencephalography （EEG） coherence at rest and during a working memory task of patients with mild cognitive impairment （MCI）. Methods： The sample consisted of 69 subjects： 35 patients （n = 17 males, n = 18 females; 52-71 years old） and 34 normal controls （n = 17 males, n = 17 females; 51 -63 years old）. Mini-mental state examination （MMSE） of two groups revealed that the scores of MCI patients did not differ significantly from those of normal controls （P〉0.05）. In EEG recording, subjects were performed at rest and during working memory task. EEG signals from F3-F4, C3-C4, P3-P4, T5-T6 and O1-O2 electrode pairs are resulted from the inter-hemispheric action, and EEG signals from F3-C3, F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs are resulted from the intra-hemispheric action for delta （1.0-3.5 Hz）, theta （4.0-7.5 Hz）, alpha-1 （8.0-10.0 Hz）, alpha-2 （10.5-13.0 Hz）, beta-1 （13.5-18.0 Hz） and beta-2 （18.5-30.0 Hz） frequency bands. The influence of inter- and intra-hemispheric coherence on EEG activity with eyes closed was examined using fast Fourier transformation from the 16 sampled channels. Results： During working memory tasks, the inter- and intra-hemispheric EEG coherences in all bands were significantly higher in the MCI group in comparison with those in the control group （P〈0.05）. However, there was no significant difference in inter- and intra-hemispheric EEG coherences between two groups at rest. Conclusion： Experimental results comprise evidence that MCI patients have higher degree of functional connectivity between hemispheres and in hemispheres during working condition, It suggests that MCI may be associated with compensatory processes during working memory tasks between hemispheres and in hemispheres. Moreover, failure of normal cortical connections may exist in MCI patients.     

论预设与生成在课堂教学中的有效整合

课堂教学是预设与生成、封闭与开放的矛盾统一体。课堂教学的生成是新课程改革中倡导的一个重要的教育理念。因此,课堂教学的预设与生成问题已成为课改进行中的研究热点。新课程改革从新的层面、新的角度阐释了预设与生成的含义及特征,指出课堂教学的实质是预设与生成的整合,只有掌握教学实践中预设与生成整合的策略,才能在教学过程中促进优质课的建设。     

基于系统动力学视野的职业教育

以系统的观点和系统动力学的思想对职业教育在教育大系统和社会系统中所占有的地位和发挥的重要作用作了分析,并对职业教育遇到的问题和解决思路进行了探讨。     

话语标记在话语生成和理解中的作用

以关联理论为基础,从认知角度对话语标记和话语标记的语用功能进行了分析,指出话语的生成和理解是用最小的努力去获得最佳效果的动态过程,是增强认知共性和语境效果的最佳手段,减少人们对话语进行处理加工时所需付出的努力,从而使交际得以顺利进行     

Numerical simulation and optimization design of the EGR cooler in vehicle

The EGR （exhaust gas recirculation） technique can greatly reduce the NOx emission of diesel engines, especially when an EGR cooler is employed. Numerical simulations are applied to study the flow field and temperature distributions inside the EGR cooler. Three different models of EGR cooler are investigated, among which model A is a traditional one, and models B and C are improved by adding a helical baffle in the cooling area. In models B and C the entry directions of cooling water are different, which mostly influences the flow resistance. The results show that the improved structures not only lengthen the flow path of the cooling water, but also enhance the heat exchange rate between the cool and hot media. In conclusion we suggest that the improved structures are more powerful than the traditional one.     

党的新一代领导人在跨世纪前后对思想政治工作的主要贡献

20世纪90年代以来，我国改革开放进入新的历史阶段。以江泽民为核心的第三代领导集体和以胡锦涛为总书记的党中央．继承和发展了毛泽东、邓小平关于思想政治工作的理论，作出了一系列加强思想政治工作的论述和决定，对党的思想政治工作作出了新的贡献。     

顺句驱动的知觉加工与互动

同声传译的顺句驱动是口译实践中最普通的现象,其内在规律遵循的是心理学知觉加工的基本原理。通过结合知觉加工的原理、互动作用和能动性等方面的分析,可以找出顺句驱动的优劣势,进而丰富翻译理论,并指导具体的口译实践。     

妈祖信仰在粤琼地区的传播及影响

通过查阅广东、海南两省60多部方志,收集有关妈祖宫庙的记载资料,并以之为基础,探讨妈祖信仰在粤琼地区传播的特点、影响以及蕴含的意义。