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Axial acoustic radiation force on an elastic spherical shell near an impedance boundary for zero-order quasi-Bessel-Gauss beam

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Chinese Physics B 2021年第4期30卷 305-318页

作者： Yu-Chen Zang wei-jun lin Chang Su Peng-Fei Wu Institute of Acoustics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Shell structures have increasingly widespread applications in biomedical ultrasound fields such as contrast agents and drug delivery,which requires the precise prediction of the acoustic radiation force under various circumstances to improve the system *** acoustic radiation force exerted by a zero-order quasi-Bessel-Gauss beam on an elastic spherical shell near an impedance boundary is theoretically and numerically studied in this *** means of the finite series method and the image theory,a zero-order quasi-Bessel-Gauss beam is expanded in terms of spherical harmonic functions,and the exact solution of the acoustic radiation force is derived based on the acoustic scattering *** acoustic radiation force function,which represents the radiation force per unit energy density and per unit cross-sectional surface,is especially *** simulated results for a polymethyl methacrylate shell and an aluminum shell are provided to illustrate the behavior of acoustic radiation force in this *** simulated results show the oscillatory property and the negative radiation force caused by the impedance *** appropriate relative thickness of the shell can generate sharp peaks for a polymethyl methacrylate *** radiation force can be obtained at small half-cone angles and the beam waist only affects the results at high *** that the quasi-Bessel-Gauss beam possesses both the energy focusing property and the non-diffracting advantage,this study is expected to be useful in the development of acoustic tweezers,contrast agent micro-shells,and drug delivery applications.

关键词： acoustic radiation force zero-order quasi-Bessel-Gauss beam impedance boundary elastic spherical shell

Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

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Neural Regeneration Research 2025年第3期20卷 779-793页

作者： Guangyong Zhang Qing Yao Chubing Long Pengcheng Yi Jiali Song Luojia Wu wei Wan Xiuqin Rao Yue lin Gen wei jun Ying Fuzhou Hua Department of Anesthesiology the Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina Key Laboratory of Anesthesiology of Jiangxi Province NanchangJiangxi ProvinceChina

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

关键词： blood–brain barrier macrophages monocytes multiple sclerosis neuroinflammation review therapy

A DESIGN OF INTELLIGENT POWER ULTRASONIC SUPPLY

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A DESIGN OF INTELLIGENT POWER ULTRASONIC SUPPLY

Quantitative ultrasound brain imaging with multiscale deconvolutional waveform inversion

2016年全国压电和声波理论及器件应用研讨会

作者： Jing-shuang GONG Hong-bin HE wei-jun lin Institute of Acoustics Chinese Academy of Science

ISBN: (纸本)9781509011902

Background, Motivation and Objective Power ultrasound is widely used in many fields such as ultrasonic motor, ultrasonic cleaning. Power ultrasonic supply is the key to drive transducer of power ultrasonic device. The transducer is drived by supply and produces ultrasonic wave. When the transducer works at resonant frequency, it outputs maximum power. But when it works after a long time, the resonant frequency will drift and the output power will decrease. In order to make the transducer work stably for a long time, it is necessary to monitor the changes of resonant frequency. Some of frequency automatic tracking devices of the traditional supply are realized by PLL(Phase-locked Loop). But the PLL is easy to unlock. Others are realized by MCU(Microcontroller Unit), but it samples the phase difference of voltage and current by analog circuit. It lacks of stability. This design puts forward a new frequency tracking method based on MCU, cooperates with the circuit design, solves the problem of frequency drift, guarantees stability. Statement of Contribution/Methods This design is composed of four parts, SPWM waveform, power amplifier, matching network, frequency automatic tracking. Power amplifier and matching network are implemented by analog circuit. SPWM waveform is realized by programming with stm32 MCU. In the frequency automatic tracking part, voltage and current get into MCU through AD transform, the MCU calculates the phase difference by using the cross-correlation algorithm, and then according to the phase difference, the SCM adjusts the resonant frequency of the transducer. Results Through experiments and debugging, this design can well realize output waveform and frequency automatic tracking with SCM, the tracking speed is fast and the stability is great. Discussion and Conclusions Compared with traditional power ultrasonic supply, the MCU calculates the phrase difference between voltage and current by using the cross-correlation algorithm. Thus can reduce t

关键词： Power ultrasonic supply Frequency automatic tracking SCM

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Chinese Physics B 2023年第1期32卷 362-372页

作者：李玉冰王建苏畅林伟军王秀明骆毅 Institute of Acoustics Chinese Academy of SciencesBeijing 100190China University of the Chinese Academy of Sciences Beijing 100049China Beijing Deep Sea Drilling Measurement Engineering Technology Research Center Beijing 100190China

High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe *** speed mapping of brain tissues provides unique information for such a *** addition,it is particularly important for building digital human acoustic models,which form a reference for future ultrasound *** ultrasound modalities can hardly image the human brain at high spatial resolution inside the skull due to the strong impedance contrast between hard tissue and soft *** carry out numerical experiments to demonstrate that the time-domain waveform inversion technique,originating from the geophysics community,is promising to deliver quantitative images of human brains within the skull at a sub-millimeter level by using ultra-sound *** successful implementation of such an approach to brain imaging requires the following items:signals of sub-megahertz frequencies transmitting across the inside of skull,an accurate numerical wave equation solver simulating the wave propagation,and well-designed inversion schemes to reconstruct the physical parameters of targeted model based on the optimization *** we propose an innovative modality of multiscale deconvolutional waveform inversion that improves ultrasound imaging resolution,by evaluating the similarity between synthetic data and observed data through using limited length Wiener *** implement the proposed approach to iteratively update the parametric models of the human *** quantitative imaging method paves the way for building the accurate acoustic brain model to diagnose associated diseases,in a potentially more portable,more dynamic and safer way than magnetic resonance imaging and x-ray computed tomography.

关键词： ultrasound brain imaging full waveform inversion high resolution digital body

Thin steel plate with thumbtack fixation in the treatment of massive presacral venous plexus hemorrhage

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Chinese Medical Journal 2011年第19期124卷 3180-3181页

作者： YU Li-ping DAI Guo-fang DUAN Jian-chun XU Yong-bo CHEN wei-jun ZHOU lin-qiu Department of General Surgery Jin Tan People＇s Hospital Affiliated to Jiangsu University Jintan Jiangsu 213200 China

Background Massive presacral venous plexus hemorrhage during radical resection of rectal carcinoma is rare, but when it occurs, bleeding can be uncontrollable, leading to death in some cases. Medical adhesive gauze sticking and packing and thumbtack compressive fixation are often used for hemostasis, but these methods are not effective in cases of uncontrollable massive hemorrhage. Therefore, identifying a practical, accurate, and reliable method of hemostasis in these cases is *** Between January 2004 and December 2009, we treated 3 patients with massive presacral venous plexus hemorrhage during resection of rectal carcinoma by placing small, trimmed thin steel plates at the bleeding sites. The plates were fixed with a saddle-type application of *** Bleeding was successfully controlled in all 3 patients, and intestinal anastomosis was carried out after hemostasis. No complications were *** Application of a small, thin steel plate to the bleeding site with thumbtack fixation is a simple and effective method of hemostasis in patients with massive presacral venous plexus hemorrhage during resection of rectal carcinoma.

关键词： thin steel plate compressive fixation massive presacral venous plexus hemorrhage

PREDICTION OF THE SKULL'S ACOUSTIC PARAMETERS IN TRANSCRANIAL FOCUSED ULTRASOUND BASED ON NEURAL NETWORK

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PREDICTION OF THE SKULL'S ACOUSTIC PARAMETERS IN TRANSCRANIA...

SIMULATION OF 2.5-DIMENSIONAL BOREHOLE ACOUSTIC WAVES WITH CONVOLUTIONAL PERFECTLY MATCHED LAYER

2016年全国压电和声波理论及器件应用研讨会

作者： Xiang-da WANG Nan-xing LI wei-jun lin Chang SU State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences National Network New Media Engineering Research Center Institute of Acoustics Chinese Academy of Sciences

ISBN: (纸本)9781509011902

Background, Motivation and Objective The model for calculating the transcranial focused ultrasound(tc FUS) field is the Westervelt equation, in which the acoustic parameters of the skull are necessary. Thus, in order to achieve the precise focusing of transcranial ultrasound, it’s of great importance and significance to obtain accurate acoustic parameters of the skull. In the past few decades, deep learning based on the neural network has got a rapid progress and is of much popularity. In this paper, through the use of computed tomography(CT) of a monkey skull from Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, we have proposed a method utilizing feed-forward neural network(FFNN) to precisely predict the acoustic parameters of the skull based on its CT with tiny errors. Moreover, the predicting results of the acoustic parameters are applied to numerically simulate the transcranial focused ultrasound field, so as to further verify the effectiveness of the proposed method. Statement of Contribution/Methods We employ the method put forward by M. Fink et al to generate the learning data set. In their model, the acoustic parameters of the skull including density, sound velocity and acoustic absorption coefficient can be calculated based on the skull’s CT data. With the learning data set, our goal is to acquire the mapping relationship between the CT data and the different acoustic parameters through FFNN, namely the appropriate FFNN structure. In the following, focused ultrasonic fields calculated by the numerical algorithm of finite difference time domain(FDTD) with the predicted and the hypothetically real acoustic parameters of the monkey skull are compared and analyzed to further demonstrate the effectiveness of the proposed method. Results Prediction results show that the density, sound velocity and acoustic absorption coefficient are precisely predicted by our method with the accuracy rate of 99.95% at least. Furthermore, comparison of the

关键词： Transcranial focused ultrasound Deeping learning Neural network

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SIMULATION OF 2.5-DIMENSIONAL BOREHOLE ACOUSTIC WAVES WITH C...

Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

2013全国压电和声波理论及器件技术研讨会

作者： Le LIU wei-jun lin Hai-lan ZHANG Xiu-ming WANG State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences

A 2.5-dimensional method using the PDE package of the commercial finite element software COMSOL Multiphysics is developed to simulate wave propagation in a *** computation is conducted in the frequency wave-number domain.A convolutional perfectly matched layer is implemented to eliminate the reflections from artificial truncation *** obtained in time domain are in good agreement with analytic solutions in a special model,which proves the validity of the method.A numerical modeling example is presented to illustrate the capabilities of the *** is shown that this method can be used to solve a variety of non-axisymmetric borehole acoustic wave propagation problems.

关键词： Borehole acoustics 2.5-dimensional Non-axisymmetric Finite element method Convolutional PML

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Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping lin jun Xu Delong Jiang Jiayang Hou Ying Liang Zhongyue Zou Xuesong Mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology School of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Contrastive Learning

Engineering N3C vacancies in hierarchical porous carbon nitride nanosheets for room temperature ultradeep photocatalytic aerobic oxidative desulfurization

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Science China Chemistry 2025年

作者： Yina Nie weijie Yang Xin Wang Xiang Li Lele wei Xiaolin Bai lin Liu Feng Fu jun Wan College of Chemistry & Chemical Engineering Research Institute of Comprehensive Energy Industrial Technology Shaanxi Key Laboratory of Chemical Reaction Engineering Yan'an University Anhui Engineering Research Center of Carbon Neutrality College of Chemistry and Materials Science Anhui Normal University

The production of ultra-low sulfur clean fuels holds global significance for improving energy efficiency and reducing environmental pollution. Photocatalytic aerobic oxidative desulfurization（PODS） offers an attractive approach to efficiently remove refractory heterocyclic aromatic sulfur compounds under mild conditions. However, the sluggish charge dynamics,insufficient molecule activation, and slow mass transfer within photocatalysts restrict the overall desulfurization efficiency,hindering the widespread application of this technology. Herein, we developed a defective g-C3N4（M1U3CN） photocatalyst with bridged N3Cvacancies and hierarchical porous structures to address these limitations. This catalyst not only demonstrates outstanding dibenzothiophene（DBT） removal efficiency of 99.6% for model oil with high conversion and selectivity but also achieves complete sulfur removal from gasoline as well as 96.7% sulfur removal for distilled diesel at room temperature,successfully achieving ultradeep aerobic oxidative desulfurization. The introduction of rich N3Cvacancies and abundant micromeso-macroporous distribution in M1U3CN enhances kinetic efficiencies by promoting charge carrier separation, mass transfer,and molecular activation simultaneously; resulting in exceptional PODS performance. This work provides a collaborative strategy to overcome kinetic challenges in aerobic oxidative desulfurization via defect and structural engineering of the catalyst.

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