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Touschek lifetime study based on the precise bunch-by-bunch BCM system at SSRF

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Nuclear Science and Techniques 2019年第9期30卷 126-133页

作者： Fang-Zhou Chen Zhi-chu Chen yi-Mei Zhou Ning zhang Bo Gao Xing-yi Xu Yong-Bin Leng Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049 China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201200 China

Continuous tracking of bunch charges is the key to maintain stable operations in a storage ring in top-up mode. Recently, a precise bunch-by-bunch beam-current measurement (BCM) system has been developed at the Shanghai Synchrotron Radiation Facility. To avoid the influence of longitudinal oscillation on the amplitudes of the sampling points, a method called two-point equilibrium sampling is introduced. The results, obtained during routine operation time, show that the relative resolution of the measurement of the bunch charges is better than 0.02%. With this high resolution, the new BCM system is able to monitor the bunch-by-bunch beam lifetime. By using the filling pattern information, the Touschek lifetime and the vacuum lifetime can also be calculated. In this paper, the principle of the new method and the experiments is presented in detail.

关键词： Beam-current measurement Bunch-bybunch Touschek lifetime Vacuum lifetime SSRF

The dopaminergic system and Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2495-2512页

作者： Yuhan zhang Yuan Liang yixue Gu International Medical College Chongqing Medical UniversityChongqingChina College of Pharmacy Chongqing Medical UniversityChongqingChina Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqingChina

Alzheimer's disease is a common neurodegenerative disorder in older *** its prevalence,its pathogenesis remains unclea *** addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this *** is a crucial catecholaminergic neurotransmitter in the human ***-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical *** r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive *** review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related *** aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

关键词： adverse drug reaction Alzheimer's disease catecholamine dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease neurotransmitter signaling pathways traditional Chinese medicine treatment

Multi-Stage-Based Siamese Neural Network for Seal Image Recognition

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 405-423页

作者： Jianfeng Lu Xiangye Huang Caijin Li Renlin Xin Shanqing zhang Mahmoud Emam School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou310018China Shangyu Institute of Science and Engineering Hangzhou Dianzi UniversityShaoxing312300China Faculty of Artificial Intelligence Menoufia UniversityShebin El-Koom32511Egypt

Seal authentication is an important task for verifying the authenticity of stamped seals used in various domains to protect legal documents from tampering and *** seal inspection is commonly audited manually to ensure document ***,manual assessment of seal images is tedious and laborintensive due to human errors,inconsistent placement,and completeness of the *** image recognition systems are inadequate enough to identify seal types accurately,necessitating a neural network-based method for seal image ***,neural network-based classification algorithms,such as Residual Networks(ResNet)andVisualGeometryGroup with 16 layers(VGG16)yield suboptimal recognition rates on stamp ***,the fixed training data categories make handling new categories to be a challenging *** paper proposes amulti-stage seal recognition algorithmbased on Siamese network to overcome these ***,the seal image is pre-processed by applying an image rotation correction module based on Histogram of Oriented Gradients(HOG).Secondly,the similarity between input seal image pairs is measured by utilizing a similarity comparison module based on the Siamese ***,we compare the results with the pre-stored standard seal template images in the database to obtain the seal *** evaluate the performance of the proposed method,we further create a new seal image dataset that contains two subsets with 210,000 valid labeled pairs in *** proposed work has a practical significance in industries where automatic seal authentication is essential as in legal,financial,and governmental sectors,where automatic seal recognition can enhance document security and streamline validation ***,the experimental results show that the proposed multi-stage method for seal image recognition outperforms state-of-the-art methods on the two established datasets.

关键词： Seal recognition seal authentication document tampering siamese network spatial transformer network similarity comparison network

Changes of Soil Water, Organic Matter, and Exchangeable Cations Along a Forest Successional Gradient in Southern China

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Pedosphere 2007年第3期17卷 397-405页

作者： YAN Jun-Hua ZHOU Guo-yi zhang De-Qiang chu Guo-Wei South China Institute of Botany Chinese Academy of Sciences Guangzhou 510650 （China）

Information on the distribution patterns of soil water content （SWC）, soil organic matter （SOM）, and soil exchangeable cations （SEC） is important for managing forest ecosystems in a sustainable manner. This study investigated how SWC, SOM, and SEC were influenced in forests along a successional gradient, including a regional climax （monsoon evergreen broad-leaved forest, or MEBF）, a transitional forest （coniferous and broad-leaved mixed forest, or MF）, and a pioneer forest （coniferous Masson pine （Pinus rnassoniana） forest, or MPF） of the Dinghushan Biosphere Reserve in the subtropical region of southern China. SWC, SOM, and SEC excluding Ca^2＋ were found to increase in the soil during forest succession, being highest in the top soil layer （0 to 15 cm depth） except for Na^＋. The differences between soil layers were largest in MF. This finding also suggested that the nutrients were enriched in the topsoil when they became increasingly scarce in the soil. There were no significant differences （P = 0.05） among SWC, SOM, and SEC. A linear, positive correlation was found between SWC and SOM. The correlation between SOM and cation exchange capacity （CEC） was statistically significant, which agreed with the theory that the most important factor determining SEC is SOM. The ratio of K^＋ to Na^＋ in the topsoil was about a half of that in the plants of each forest. MF had the lowest exchangeable Ca^2＋ concentration among the three forests and Ca^2＋：K^＋ in MPF was two times higher than that in MF. Understanding the changes of SWC, SOM, and CEC during forest succession would be of great help in protecting all three forests in southern China.

关键词： forest succession soil exchangeable cations soil organic matter soil water content

Contribution of neutrophils in the pathogenesis of rheumatoid arthritis

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The Journal of Biomedical Research 2020年第2期34卷 86-93页

作者： Lingshu zhang yi Yuan Qiang Xu Zhengyu Jiang Cong-Qiu chu Division of Arthritis and Rheumatic Diseases Oregon Health&Science UniversityPortlandOR 97239USA Rheumatology Section VA Portland Healthcare SystemPortlandOR 97239USA Department of Rheumatology and Immunology the First Hospital of Jilin UniversityChangchunJilin 130021China

Neutrophils are major innate immune effector cells for host defense and have been a topic of active research for their participation in the pathogenesis of autoimmune inflammatory diseases including rheumatoid arthritis(RA)due to recently discovered neutrophil extracellular trap(NET) formation. NET formation and other mechanisms leading to the release of neutrophil nuclear and cytoplasmic contents are implicated as a source of citrullinated antigens in RA. Further investigations are required to delineate what factors diverge neutrophils from host defense to autoimmune response in RA.

关键词： neutrophils rheumatoid arthritis NET formation

Current status of drug therapy for chronic hepatitis B

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World Journal of Gastroenterology 2025年第2期31卷 1-12页

作者： chuang Jiang Zhi-Hong zhang Jia-Xin Li Division of Liver Surgery Department of General Surgery and Laboratory of Liver Surgeryand State Key Laboratory of Biotherapy and Collaborative Innovation Center of BiotherapyWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of General Surgery Dafang County People's HospitalBijie 551600Guizhou ProvinceChina

In this editorial,we comment on the article by Meng et *** hepatitis B(CHB)is a significant global health problem,particularly in developing *** B virus(HBV)infection is one of the most important risk factors for cirrhosis and hepatocellular *** and treatment of HBV are key measures to reduce *** present,drug therapy can effectively control virus replication and slow disease progression,but completely eliminating the virus remains a ***-HBV treatment is a long-term process,and there are many kinds of antiviral drugs with different mechanisms of action,it is essential to evaluate the safety and efficacy of these drugs to reduce side effects and improve patients’*** will summarize the current status of CHB drug treatment,hoping to provide a reference for the selection of clinical antiviral drugs.

关键词： Chronic hepatitis B Hepatitis B virus Anti virus Drug treatment Therapy

Dual‑Atom Nanozyme Eye Drops Attenuate Inflammation and Break the Vicious Cycle in Dry Eye Disease

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Nano-Micro Letters 2024年第6期16卷 439-457页

作者： Dandan chu Mengyang Zhao Shisong Rong Wonho Jhe Xiaolu Cai yi Xiao Wei zhang Xingchen Geng Zhanrong Li Xingcai zhang Jingguo Li Henan Eye Hospital Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhou 450003People’s Republic of China Department of Ophthalmology Mass Eye and EarMass General BrighamHarvard Medical SchoolBostonMA 02114USA School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA College of Chemistry Zhengzhou UniversityZhengzhou 450001People’s Republic of China

Dry eye disease(DED)is a major ocular pathology worldwide,causing serious ocular discomfort and even visual *** incidence of DED is gradually increasing with the highfrequency use of electronic *** inflammation is core cause of the DED vicious cycle,reactive oxygen species(ROS)play a pivotal role in the vicious cycle by regulating inflammation from ***,current therapies merely targeting inflammation show the failure of DED ***,a novel dual-atom nanozymes(DAN)-based eye drops are *** antioxidative DAN is successfully prepared by embedding Fe and Mn bimetallic single-atoms in N-doped carbon material and modifying it with a hydrophilic *** in vitro and in vivo results demonstrate the DAN is endowed with superior biological activity in scavenging excessive ROS,inhibiting NLRP3 inflammasome activation,decreasing proinflammatory cytokines expression,and suppressing cell ***,the DAN effectively alleviate ocular inflammation,promote corneal epithelial repair,recover goblet cell density and tear secretion,thus breaking the DED vicious *** findings open an avenue to make the DAN as an intervention form to DED and ROSmediated inflammatory diseases.

关键词： Dry eye disease DAN Dual-atom nanozyme Vicious cycle NLRP3 inflammasome Nanomedicine

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong zhang Zhiying Chen yinyi Xiong Qin Zhou Ling-Qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

Real-Time Monitoring and Quantitative Evaluation of Cavitation Bubbles Induced by High Intensity Focused Ultrasound Using B-Mode Imaging

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Chinese Physics Letters 2014年第3期31卷 91-95页

作者： YU Jie CHEN chu-yi CHEN Gong GUO Xia-Sheng MA Yong TU Juan zhang Dong Key Laboratory of Modern Acoustics School of Physics Nanjing University Nanjing 210093 Traditional Chinese Medicine Hospital of Jiangsu Province Nanjing 210023 State Key Laboratory of Acoustics Chinese Academy of Sciences Beijing 100190

A software-based method is proposed to eliminate the flooding interference strips in B-mode images, and to evaluate the cavitation bubbles generated during high intensity focused ultrasound （HIFU） exposures. In vitro tissue phantoms are exposed to 1.12 MHz HIFU pulses with a fixed 100 Hz pulse repetition frequency. HIFU-induced cavitation bubbles are detected as hyperechoic regions in B-mode images. The temporal evolution of cavitation bubbles, generated by HIFU pulses with varying driving amplitude and pulse length, is analyzed by measuring the time-varying area of the hyperechoic region. The results show that： first, it is feasible to monitor HIFU-induced cavitation bubble activity in real-time using B-mode imaging; second, more cavitation bubbles can be generated with higher acoustic energy delivered; third, the hyperechoic region is observed to shrink gradually after ceasing the HIFU pulses, which indicates the dissolution of cavitation bubbles. This work will be helpful for developing an effective tool to realize real-time monitoring and quantitative evaluation of HIFU-induced cavitation bubble activity using a current commercialized B-mode machine.

关键词： CAVITATION RESEARCH HIGH-intensity focused ultrasound IMAGING systems QUANTITATIVE research PHYSICS research