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Acoustic streaming has a significant effect on accelerating material mixing and flow field disturbance. To explore the characteristics of acoustic streaming in the cylindrical tube array field under the action of an acoustic wave, we derive the dimensionless acoustic streaming control equation and establish a numerical calculation model of acoustic streaming. The effects of acoustic incidence angle, acoustic Reynolds number, and Strouhal number on the acoustic streaming vortex flow field in the tube array were investigated. The numerical results show that with the change in acoustic parameters, the acoustic streaming in the tube array presents rich changes in the vortex flow field, and there are flow field phenomena such as shrinking, merging, tearing, and splitting of the vortex structure. Toward the walls of each tube, there is a strong acoustic streaming flow velocity. Besides, there is also a large streaming velocity on the interface of the adjacent acoustic streaming vortices. The inner streaming vortex structure in the acoustic boundary layer decreases with the increase in the acoustic Reynolds number, but the intensity of the inner streaming vortex and outer streaming vortex increases rapidly, and the disturbance effect of the flow field is enhanced. With the increase in the dimensionless acoustic frequency (or Strouhal number), although the structure and intensity of the inner streaming vortex decrease, the velocity gradient on the wall of the cylindrical tube increases, which is beneficial to destroy the flow boundary layer of the cylindrical tube wall and accelerate the instability of the wall flow field.

Background: Stereoelectroencephalography (SEEG), as a minimally invasive method that can stably collect intracranial electroencephalographic information over long periods, has increasingly been applied in the diagnosis and treatment of intractable epilepsy in recent years. Over the past 20 years, with the advancement of materials science and computer science, the application scenarios of SEEG have greatly expanded. Bibliometrics, as a method of scientifically analyzing published literature, can summarize the evolutionary process in the SEEG field and offer insights into its future development prospects. Methods: This article selected all the literature records retrieved on November 4, 2024, from the Web of Science Core Collection (WoSCC). The search terms were as follows: "Stereo-electroencephalography" or "Stereo electroencephalography" or "Stereo-EEG" or "Stereo EEG" or "SEEG." The document types included were research articles and reviews. For analysis, VOSviewer, CiteSpace, and the R package "bibliometrix" were employed to analyze various aspects of the SEEG field, including authors, institutions, countries and regions, and research hotspots. Results: We reviewed a total of 1,383 non-duplicate literature records from 2002 to 2023, including 1,241 research articles, 116 review articles and 26 letters. Observing the annual publication trends, there has been an overall increase since 2002. The most influential journal in this field is Epilepsia. Other journals with considerable impact include Clinical Neurophysiology , Epileptic Disorders , Epilepsy Research , NeuroImage , and Epilepsy & Behavior. The top 5 most influential scholars are Bartolomei F, Tassi L, Nobili L, Russo GL, and Mc Gonigal A. As for the analysis of countries and regions, France occupies a leading position in this field with its early start, while China and the United States have also emerged as focal points since 2020. Research on SEEG has expanded beyond its initial use for localizing epileptic foci and thermo-coagulation treatments and have been employed as a medium to facilitate real-time prediction of epileptic seizures and enabling the exploration of brain network connectivity. Conclusion: As a minimally invasive tool for collecting intracranial electroencephalographic signals, SEEG continues to offer vast potential for development and application. Advances in electrode materials and robotic-assisted stereotactic techniques, have enabled SEEG to simultaneously sample multiple brain regions, acquire electrical signals from deep brain structures. These advantages significantly enhance the precision of epileptic focus localization in diagnosis and treatment, addressing the limitations of subdural electrodes. Through bibliometric analysis, this paper traces the developmental trajectory of SEEG and identifying key technological milestones, thereby providing a reference for scholarly research directions. [ABSTRACT FROM AUTHOR]

Background: The mechanistic effects of gamma transcranial alternating current stimulation (tACS) on hippocampal gamma oscillation activity in Alzheimer's Disease (AD) remains unclear. This study aimed to clarify beneficial effects of gamma tACS on cognitive functioning in AD and to elucidate effects on hippocampal gamma oscillation activity. Methods: This is a double-blind, randomized controlled single-center trial. Participants with mild AD were randomized to tACS group or sham group, and underwent 30 one-hour sessions of either 40 Hz tACS or sham stimulation over consecutive 15 days. Cognitive functioning, structural magnetic resonance imaging (MRI), and simultaneous electroencephalography–functional MRI (EEG-fMRI) were evaluated at baseline, the end of the intervention and at 3-month follow-up from the randomization. Results: A total of 46 patients were enrolled (23 in the tACS group, 23 in the sham group). There were no group differences in the change of the primary outcome, 11-item cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog) score after intervention (group*time, p = 0.449). For secondary outcomes, compared to the control group, the intervention group showed significant improvement in MMSE (group*time, p = 0.041) and MoCA scores (non-parametric test, p = 0.025), which were not sustained at 3-month follow-up. We found an enhancement of theta-gamma coupling in the hippocampus, which was positively correlated with improvements of MMSE score and delayed recall. Additionally, fMRI revealed increase of the local neural activity in the hippocampus. Conclusion: Effects on the enhancement of theta-gamma coupling and neural activity within the hippocampus suggest mechanistic models for potential therapeutic mechanisms of tACS. Trial registration: ClinicalTrials.gov, NCT 03920826; Registration Date: 2019-04-19. [ABSTRACT FROM AUTHOR]

Aims: We aimed to investigate mesial temporal lobe abnormalities in mesial temporal lobe epilepsy (MTLE) patients with hypersynchronous (HYP) and low‐voltage fast rhythms (LVF) onset identified by stereotactic electroencephalography (SEEG) and evaluate their diagnostic and prognostic value. Methods: Fifty‐one MTLE patients were categorized as HYP or LVF by SEEG. High‐resolution MRI volume‐based analysis and 18F‐FDG‐PET standard uptake values of hippocampal and amygdala subfields were quantified and compared with 57 matched controls. Further analyses were conducted to delineate the distinct pathological characteristics differentiating the two groups. Diagnostic and prognostic prediction performance of these biomarkers were assessed using receiver operating characteristic curves. Results: LVF‐onset individuals demonstrated ipsilateral amygdala enlargement (p = 0.048) and contralateral hippocampus hypermetabolism (p = 0.042), pathological results often accompany abnormalities in the temporal lobe cortex, while HYP‐onset subjects had significant atrophy (p < 0.001) and hypometabolism (p = 0.013) in ipsilateral hippocampus and its subfields, as well as amygdala atrophy (p < 0.001), pathological results are highly correlated with hippocampal sclerosis. Severe fimbria atrophy was observed in cases of HYP‐onset MTLE with poor prognosis (AUC = 0.874). Conclusion: Individuals with different seizure‐onset patterns display specific morphological and metabolic abnormalities in the amygdala and hippocampus. Identifying these subfield abnormalities can improve diagnostic and prognostic precision, guiding surgical strategies for MTLE. [ABSTRACT FROM AUTHOR]

Epilepsy is a common chronic neurologic disorder, with about 30%‐40% of patients suffering from recurrent seizures despite receiving enough antiseizure medication. Growing evidence of extensive structural and functional research has revealed that epilepsy is a network disorder, and the network investigation is crucial in the presurgical evaluation. This narrative review is aimed at providing an overview of the conceptual development of epileptic surgery, the epileptic network formation, and the network‐oriented strategy in clinical practice. We searched the PubMed database before October 2022 with no language or regional restrictions for studies of network exploration in epilepsy patients. The study eligibility criteria were original connectivity or network research studies using neuroimaging or neurophysiological approaches, focusing on seizure localization, neuropsychological evaluation, neuromodulation, or surgical prognosis. The initial search revealed 2046 studies. The selection process presented 746 papers that meet the inclusion criteria. The results indicated that epilepsy was characterized by the alternation of brain networks, which account for the clinical, electrographic, and neurocognitive phenomena related to human seizures and changes across different disease stages. Hubs have garnered significant attention due to their extensive connections, which make them prone to facilitating the spread of seizures to various brain regions. Unlike the seizure onset zone, the removal of the majority of these ictogenic nodes demonstrated a significant correlation with positive outcomes. Therefore, performing a network analysis during the epilepsy presurgical evaluation seems essential and will influence surgical decisions. It is hoped that studying the network of epilepsy will enhance our ability to determine the most appropriate surgical strategy for patients with epilepsy, thus contributing to success in terms of effective seizure control with maximal sparing or even improvement of brain functioning. [ABSTRACT FROM AUTHOR]

Background: Predicated on Vygotsky's zone of proximal development (ZPD), dynamic assessment (DA) integrates teaching with assessment in a single activity by providing mediation to help learners perform beyond their independent functioning and simultaneously promote learner development. It advantages over traditional psychometric tests in that DA can not only reveal the learners' actual level of development from their independent performance as what the traditional tests did but also their potential level of development from the mediations the learners need during the mediator-learner interactions. However, the number of learners a DA assessor can help is limited due to the time demand of mediator-learner interactions. To overcome this weakness, researchers are turning to computerized dynamic assessment (C-DA). Methods: The study aimed to find out the learners' difficulties in reading comprehension, the effects of C-DA and the learners' reflections on the C-DA program. Multiple choice questions in the reading comprehension section were adapted from CET4 (College English Test, Band 4). Two groups of students participated in the present study. In the pilot study, a group of students were asked to write down their thinking process after they finished a reading test, from which the students' difficulties in reading comprehension test were identified and mediations were worked out afterwards. The mediation levels and the scoring scale were also determined and put into the C-DA program devised for the main study. Another group of students were asked to do a reading test using C-DA. After the test, a learner profile capturing the students' performances in the test was generated from the program. Finally, a questionnaire was distributed to collect data for the students' reflections on C-DA. Results: It was found that the learners mainly encountered three difficulties in their reading comprehension test: (1) new words were the biggest barrier; (2) learners felt hard to locate on the relevant sentences in the original passage from the information provided in the question; (3) their inferential abilities are weak. The analysis of the data generated by the C-DA program indicated that C-DA far exceeded the traditional static assessment for its stronger diagnostic capacities and the deeper insights it provided for subsequent teaching. The results of the questionnaire showed that C-DA was greatly welcomed by the students and believed to be particularly helpful in building up confidence for those low achievers as identified in traditional static assessment. Conclusions: The major contribution of the present study was to implement DA principles to larger scale study with the use of computer technology and gain valuable insights for future studies. However, limitations remained and future studies should try to address the issues discussed in the present study.

While functional MRI (fMRI) studies have mainly focused on gray matter, recent studies have consistently found that blood-oxygenation-level-dependent (BOLD) signals can be reliably detected in white matter, and functional connectivity (FC) has been organized into distributed networks in white matter. Nevertheless, it remains unclear whether this white matter FC reflects underlying electrophysiological synchronization. To address this question, we employ intracranial stereotactic-electroencephalography (SEEG) and resting-state fMRI data from a group of 16 patients with drug-resistant epilepsy. We find that BOLD FC is correlated with SEEG FC in white matter, and this result is consistent across a wide range of frequency bands for each participant. By including diffusion spectrum imaging data, we also find that white matter FC from both SEEG and fMRI are correlated with white matter structural connectivity, suggesting that anatomical fiber tracts underlie the functional synchronization in white matter. These results provide evidence for the electrophysiological and structural basis of white matter BOLD FC, which could be a potential biomarker for psychiatric and neurological disorders. Whether connectivity in white matter detected by functional MRI relates to underlying electrophysiological synchronization is unclear. Here, the authors show that blood-oxygenation-level-dependent (BOLD) functional connectivity and intracranial stereotactic-electroencephalography (SEEG) connectivity are correlated across a wide range of frequency bands. [ABSTRACT FROM AUTHOR]